IamCheEng Magazine 9-2013

January 4, 2018 | Author: bemserto | Category: Heat Exchanger, Water Purification, Ammonia, Urea, Natural Gas
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I am a Chemical Engineer • We discuss Chemical Engineering and provide some information and news. • We would like to think of our page as an exchange page of experience and information. https://www.facebook.com/IamCheEng

Slogan Connecting chemical engineers.

Vision Improving the chemical Engineering skills to meet the work environment & to decrease the gap between study and work.

Mission Gathering information about any chemical engineering fields.

How about a career where the opportunities are endless? Trying not to sound like an advertisement, I'd like to describe some of the more common careers pursued with a Chemical Engineering degree. Firstly, if you're considering studying Chemical Engineering, but you're a little timid because of the horror stories that you hear, you actually may want to think about it some more! I've actually heard someone say, "How hard can it be?" Really hard, but really rewarding too! True, the material involved in far from easy and some of the concepts take hours (and in some cases years!) to master, but isn't having this degree worth the effort? I think that you'll find that it will be. I guess what I'm saying is, if you're serious about wanting to be a Chemical Engineer, go for it and don't be afraid to fail (as long as you've done your best). If you're not sure what you want to do, take some preliminary courses first and then ask some of the current students what they think so far and compare you're academic merit to theirs. Now, once you've got the degree, the fun really starts. I suggest taking the Fundamentals of Engineering Exam (FE Exam) shortly before or after graduation. The after 4 or 5 years of industrial work, you can take the Professional Engineering Exam (PE Exam) and become a Certified Professional Engineer. Always a good idea to take these exams, remember, if you don't someone else will and they'll probably get your job! Speaking of jobs, what kind of work can you do with a Chemical Engineering degree? "I love designing equipment, optimizing processes, and performing financial analyses on these processes." --DESIGN ENGINEER "I like to analyze existing processes and suggest changes needed to increase profitability" --PROCESS ENGINEER "I really like designing and performing experiments to test theories and check the economic impact of plant changes on a small scale" --RESEARCH AND DEVELOPMENT ENGINEER

"I'm a people person and I don't like being trapped in one place all of the time" --FIELD ENGINEER OR TECHNICAL SALES PERSONNEL

"I want to be a physician" --MEDICAL SCHOOLS REALLY LIKE CHEMICAL ENGINEERS "I'm out of school, I'm tired of engineering and I never want to do it again" --YOU GRADUATED WITH ONE OF THE MOST DIFFICULT UNDERGRADUATE DEGREES THAT THERE IS. MAYBE YOU'D RATHER LOOK INTO BECOMING A FORENSIC CHEMIST OR AN ENVIRONMENTAL CONSULTANT. WHATEVER YOU DECIDE TO DO, YOU HAVE A QUALITY EDUCATION THAT NO ONE CAN TAKE FROM YOU. A Chemical Engineering degree may not be a free ride through life, but it does provide a solid base to start a wide variety of careers and after all, wasn't that you're objective to begin with? Below you'll find an interview that was completed many years ago (circa 2000) that high schools students have used to help them make their decision regarding chemical engineering.

Interview with a Chemical Engineer

NOTE

Many students find their way to The Chemical Engineers’ Resource Page in search of a chemical engineer to interview for career research. We applaud these students and are happy to help in their quest to learn more about chemical engineering. The following are 17 of the most commonly asked questions.

Why Become a Chemical Engineer? and Interview with a Chemical Engineer BY Christopher Haslego Owner and Chief Webmaster www.cheresources.com

Interview with a Chemical Engineer 1. How did you come to choose this career? Why did it appeal to you? Actually, as with many college students, I changed my major course of study during my freshman year. I began college as a computer science major. I quickly found that computer science just was not for me. I explored the campus and found a course of study that combined technical thinking with a topic that had always interested me…..chemistry. As I learned more about chemical engineering, I just knew it was for me.

2. What kind of training or education did this career require and what college or university did you attend? The training included a 5 year (sometimes 4 depending on the university that you attend) academic cirriculum. I attended West Virginia University in Morgantown, WV. My classes included 4 units of Calculus, at least 6 of chemistry, some general engineering which included computer programming, thermodynamics, transport analysis, fluid dynamics, heat transfer, material and energy balance (2 classes), process control, chemical reaction engineering, separation technology, and chemical process design just to name some of the more important classes. However, at a university type setting, you'll also be required to take classes known as core requirements to make you a "well rounded individual". Mine included Theatre, Spanish, Criminology, Political Science, Geology, and Physiology....you get the picture. You can go to WVU's chemical engineering page at www.cemr.wvu/~wwwche/ and look under the "Undergraduate program" to see a complete cirriculum there.

3. Are there any other skills beyond formal training that someone needs to do this job? Your college training is just the beginning of your education. When you land your first job, you’ll learn how the “real” world works. There are numerous skills that chemical engineers entering a chemical plant environment just do not know. You will learn many aspects of the business world, details of the equipment and process that you work with, and other “political” issues of the workplace. While the training that you receive in college is extremely important, I’d say that most people would agree hat on-the-job training is where they learned the skills that made them a good engineer. These are all reasons why it’s so hard to land that first job without any experience. In short, many people will know more than you and will be more productive much faster.

Interview with a Chemical Engineer 4. How long is a typical work day? What time does your day end? I begin work at 8:00 A.M. and I generally finish between 5 and 6 P.M. I should mention that I now work in an office environment. I began my career in a chemical plant, but the hours where the same. The problem was that it was not uncommon to receive calls on weekends or late at night if problems occurred at the plant. I work this schedule five days a week (Monday through Friday).

5. What is the starting salary or hourly wage for this job? Is there overtime pay? The starting salary is usually around $45,000 per year but can be as low as $38,000 or as high as $50,000 per year. Most chemical engineers work on a fixed salary every two weeks or month. This means that they do not earn extra money for working more than 40 hours per week. Most employers are liberal with salary employees. For example, you may work 50 hours one weeks, and only 35 the next. Usually, I’d say that the yearly average works out to be near 40 hours per week, but some people prefer to (or are required to) work more.

6. How can you advance your career as a chemical engineer? The best way for anyone to advance in their career is to separate themselves from other employees. Stand out, do something great! In general, the best ways to do this are to earn money for the company by finding ways to manufacture products cheaper, find unique solutions to complicated problems, or increase the efficiency of the way that you and others work. All of these will help the company that you work for perform better. It will also help you succeed.

7. How much paid vacation time do you receive? I receive two weeks paid vacation, two “float” holidays, and two personal days. That’s a total of 14 paid days off per year. During my fifth year of service with my company, I’ll receive an additional 5 days per year and there are further increases the longer that you’re with the company. Although some companies place restrictions on the number of paid sick days that one can receive, mine does not. We have a simple policy, “if you’re sick, don’t come to work” (this is not very common and people appreciate it and it is seldom, if ever, abused).

Interview with a Chemical Engineer 8. Do you have a retirement plan? What is included? My company offer its employees a standard retirement package called a 401K. This allows employees to put money into an account (without being taxed) to save for retirement. My company automatically contributes 3% of my salary to this account and I can add up to 14% of my annual salary (up to $10,000 per year) into the account. My company, additionally, matches 50% of the first 6% that I contribute. Essentially, if I save 6% of my salary, my company puts in 6% of my salary. Don’t overlook the importance of saving for retirement when you begin your career. Young workers often begin saving too late and may delay their retirement. This money is later taxed when it is withdrawn after you retire.

9. Does the job have medical or dental benefits? Is it full coverage or is there a deductible or co-payment? I have both medical and dental benefits. With the cost of healthcare, very few companies offer “full” coverage. I pay (very little) for these insurance plans and my employer pays the remaining amount. Most dental work is covered at 80% (check-ups and an annual x-ray are covered at 100%). I have a small co-pay for hospital and doctor visits, but under normal circumstances I have to visit my Primary Care Physician (PCP) and coordinate my care with her. To avoid the circus that healthcare has become….try to stay healthy :)

10. What are three things that you enjoy about your job? I enjoy most everything about my job! I work as a design engineer for a company that supplies heat transfer equipment to the chemical industry. I also do some marketing and sales work as well. I guess I enjoy the following the most: a. The independent work environment (no one looking over my shoulder) b. Knowing that I’m directly responsible for helping my company to succeed c. Being able to travel anywhere in the US at any time that I choose

11. What are some things that you do not enjoy? I spend a lot of time on the phone, which really is not my favorite thing to be doing, but it’s important nonetheless. Sometimes, it can be hard to accomplish goals because of the “official” channels that you have to work through…this can be frustrating.

Interview with a Chemical Engineer 12. How long have you been working in this occupation? How long do you expect to remain in this field? If you are going to make a change, why? I’ve been in my current position for two years now. I also working for another company for a year. I made the change because I really did not feel comfortable with my last employers. They did not encourage “forward” thinking at all. Creativity was not encouraged for fear that an idea may not work. This is not a good environment for a young engineer. I made the change and I’ve glad that I did ever since. My current employer goes out of their way to encourage new ideas and we’re a better company because of it.

13. How much of a demand do you see for this occupation in the future? When I graduated from college in 1998, there was a great demand for chemical engineers. Naturally demand goes up and down depending on the economy and how many people graduate each year. Generally, I’d say that there is always a need for good chemical engineers. Chemical engineers can perform many different functions. Probably why you don’t hear of many chemical engineers who are out of work.

14. What high school classes are good for preparing to become a chemical engineer? This is an easy question. While the classes are free, take as much math and science as you possibly can. They will only prepare you better for college and give you an advantage over your peers who will probably be very intelligent.

15. What advice would you give to someone considering this occupation? Be ready to work hard to get through college. Don’t get discouraged. If at all possible, DO AN INTERNSHIP, DO AN INTERSHIP, DO AN INTERSHIP. An internship will give you an opportunity to get some experience before you graduate. The field is very rewarding and you most likely will never have to worry about finding a job for the rest of your life. Instead, you’ll only worry will be finding a job that you enjoy.

Interview with a Chemical Engineer 16. Where are job for chemical engineers available (rural, urban)? Most chemical plants are found in rural areas, so to begin you’re career, you may find yourself in a remote area. After you gain some valuable experience, you may consider a bit of a career change and may be able to land a good job in a more urban area (this is pretty much what I did). My first job was in rural South Carolina and now I reside in beautiful Richmond, VA.

17. Did you specialize in any topic in particular? In school, I emphasized polymers (plastics) in my studies. This helped get me my first job in a polymer plant. Now I concentrate on heat transfer (one topic in chemical engineering).

18. How does chemistry enter into your profession? For example: As a chemical engineer, you may have to separate water and benzene sometime....you had better know how the two interact chemically before you start. Do you know if they are miscible in one another? "Miscible" is a term used to describe two liquids that mix thoroughly....like water and alcohol. But water and oil are "Immiscible" in that the oil "floats on top of the water"......this is just one example of how chemistry is very important to a chemical engineer. If you're going to be responsible for moving, separating, and reacting chemicals...you better know about the chemicals and how they react to one another first! Some of the chemical knowledge will also come with experience. For example, if someone were to ask you how to remove caffeine from coffee beans, what would you recommend? Experience tells me that there are two basic, industrially accepted methods. One uses a solvent known as methyl chloride and the other uses carbon dioxide under extremely high pressure (supercritical carbon dioxide). The use of methyl chloride is an older method and requires additional precautions because methyl chloride is poisonous so one must be sure that is does not contaminate the coffee. Using supercritical carbon dioxide requires more expensive equipment, but the risk on contamination is no longer there because carbon dioxide is not poisonous to humans. Using carbon dioxide to decaffeinate coffee has been advertised as "natural decaffeination".

steady, low flow for a variety of types of media.Dosing pumps are used in a on the principles of dynamic pumps or variety of commercial, industrial, positive displacement pumps depending municipal, and maritime applications. on the design. Dynamic pumps produce Examples include agriculture and a variable flow suited for generating horticulture, dairy farms, breweries and high flow rates with low viscosity distilleries, construction, food service fluids, while positive displacement and food processing, power generation, pumps produce a constant flow suited and oil and gas production. Dosing for producing high pressures (and low pumps are also used in the aerospace flow rates) with high viscosity fluids. and defense, automotive, machine tool, Most dosing pumps are positive mining, medical, pharmaceutical, displacement pumps, which provide semiconductor, and paper industries.

Dosing pumps can operate based

Bernoulli equation In fluid dynamics, Bernoulli's principle states that for an inviscid flow, an increase in the speed of the fluid occurs simultaneously with a decrease in pressure or a decrease in the fluid‘s potential energy.

Operation of Spiral Heat Exchangers: The hot fluid enters at the corner of the unit and flows from the inside outward. The cold fluid enters at the periphery and flows towards the center.Thus, true countercurrent flow is achieved. Advantages of Spiral type: - Efficient use of Temperature Difference. - Low Fouling (Self Cleaning). - High Overall Heat Transfer Coefficient. - Easy Maintenance. - Space Saving.

difference between steady and unsteady flow: steady: A steady flow is one in which the conditions (velocity, pressure and cross-section) may differ from point to point but DO NOT change with time. unsteady: If at any point in the fluid, the conditions change with time, the flow is described as unsteady.

steam trap: Mostly, steam traps are automatic valves that discharge condensate and some non-condensable gasses. In a perfect world, they perform this task without consuming much live steam in the system. The most important functions a steam trap performs are the following: 1. They get rid of condensate as soon as it is formed 2. They get rid of non-condensable gasses A Steam Trap performs two functions. First, it is an air vent. As steam fills the pipes on startup it must displace air, and during equipment operation all air formed must be vented. Secondly, it is a water outlet valve, which allows residual water to be removed from the steam system faster than it is formed.

Plate Heat Exchangers have a high heat transfer rate compared to other types of heat exchangers due to their large surface area. They are composed of a number of thin metal plates compressed together into a ‗plate pack‘ by two pressure plates. Within a plate heat exchanger, the fluid paths alternate between plates allowing the two fluids to interact, but not mix, several times in a small area. Each plate is corrugated to increase the surface area and maximize heat transfer. Plate Heat Exchangers have a number of applications in the pharmaceutical, petrochemical, chemical, power, industrial dairy, and food & beverage industry.Plate heat exchangers are ideal for applications where the fluids have relatively low viscosity with no particles. Also they are an ideal choice where there is a close approach between product outlet temperature and service inlet temperature. Plate heat exchangers consist of thin, corrugated plates which are gasketted or Cu brazed. The plates are tightened into a plate pack inside a frame, with product in alternate channels, and service fluid in between product channels.Plate heat exchangers are small, yet efficient. It is possible to have a Plate exchanger with the same thermal capacity of a Shell & Tube heat exchanger five times its size. The compact design conserves space in the heat exchanger environment, as well as material cost. Plate heat exchangers are available in a variety of sizes and materials to suit many different applicationsand industries.

diameter and 1.2 to 2.4 m in height .Feed enters near the bottom of products using compressed air instead the loop through a venture injector. of mechanical impacts due to which Centrifugal classification of the the micro size is very fine. Micro ground particles takes place at the milled products are obtained in upper bend of the loop. The operating microns after the material collide with gas enters the grinding chamber each other and reduce themselves by through energizing nozzles placed in attrition and collision.which consists the wall. A discharge opening in the of grinding chamber takes the shape of inner wall leads to a cyclone separator an oval loop of pipe 25 to 200 mm in and a bag collector of the product.

Jet Mill works on micronizing of

Brief on Ammonia production from Natural Gas 1) Feed-stock desulphurization This part of the process is to remove the sulfur from the feed-stock over a Zinc oxide catalyst bed, as sulfur is poison to the catalysts used in the Subsequent processed. The sculpture level is reduced to less than 0.1 ppm in this part of the process. 2) Primary Reforming The gas from the desulphuriser is mixed with process steam, usually coming from an extraction turbine, and steam gas mixture is then heated further to 500-600 °C in the convection section before entering the primary reformer. Sometimes in some plants the preheated steam/gas mixture is passed through an adiabatic pre-reformer and reheated in the convection section before entering the primary reformer.

Brief on Ammonia

production from Natural Gas -

The amount of process steam is given to adjust steam to carbon-molar ratio (S/Cratio), which should be around 3.0 for the reforming processes. The optimum ratio depends on several factors, such as feed-stock quality, purge gas recovery, primary reformer capacity, shift operation and the plant steam balance. In new plants, S/C ratio may be less than 3.0. The primary reformer consists of a large number of high-nickel chromium alloy tubes filled with nickel-containing reforming catalyst in a big chamber (Radiant box) with burners to provide heat. The overall reaction is highly endothermic and additional heat is provided by burning of gas in burners provided for the purpose, to raise the temperature to 780830 °C at the reformer outlet. The composition of gas leaving the reformer is given by close approach to the following chemical equilibrium: CH4 + H2O = CO + 3H2 CO + H2O = CO2 + H2 The heat for the primary reforming is supplied by burning natural gas or other gaseous fuels, in the burners of a radiant box containing catalyst filled tubes. The flue gas leaving the radiant box has temperature in excess of 900 °C, after supplying the high level heat to the reforming process. About 50-60% of fuel‘s heat value is directly used in the process itself. The heat content (waste heat) of the fluegas is recovered in the reformer convection section, for various process and steam duties. The fuel energy required in the conventional reforming process is 40-50% of the process feed energy. The flue-gas leaving the convection section at 100-200 °C is one of the main sources of emissions from the plant. These emissions are mainly CO2, NOx, with small amounts of SO2 and CO.

3) Secondary reforming Only 30-40% of the hydrocarbon feed is reformed in the primary reformer because of the chemical equilibrium at the actual operating conditions. The temperature must be raised to increase the conversion. This is done in the secondary reformer by internal combustion of part of the gas with process air, which also provides the nitrogen for the final synthesis gas. In the conventional reforming process the degree of primary reforming is adjusted

Brief on Ammonia

production from Natural Gas -

so that the air supplied to the secondary reformer meets both the heat and the stoichiometric synthesis gas requirement. The process air is compressed to the reforming pressure and heated further in the primary reformer convection section to about 600 °C. The process gas is mixed with the air in a burner and then passed over a nickel-containing secondary reformer catalyst. The reformer outlet temperature is around 1000 °C, and up to 99% of the hydrocarbon feed (to primary reformer) is converted, giving a residual methane content of 0.2-0.3 (dry gas bases) in the process gas leaving the secondary reformer. The process gas is cooled to 350-400 °C in a waste heat boiler or waste heat boiler/super heater down stream from the secondary reformer. 4) Shift conversion (High & Low) The process gas from the secondary reformer contains 12-15% CO (dry gas bases) and most of the CO is converted in the shift section according to the reaction: CO + H2O = CO2+ H2 In the high temperature shift conversion (HTS), the gas is passed through a bed of iron oxide/Chromium oxide catalyst at around 400 °C, where the CO content is reduced to about 3% (dry gas bases), limited by the shift equilibrium at the actual operating temperature. There is tendency to use copper containing catalyst to increase conversion. The gas from the HTS is cooled and passed through the low temperature shift (LTS) converter. The LTS is filled with a copper oxide/Zinc oxide-based catalyst and operates at about 200-220 °C. The residual CO content is important for the efficiency of the process. Therefore, efficiency of shift step in obtaining the highest shift conversion is very important. 5) CO2 Removal The process gas from the low temperature shift converter contains mainly H2, N2, CO2, and excess process steam. The gas is cooled and most of the excess steam is condensed before it enters the CO2 removal section. This condensate usually contains 1500-2000 ppm of ammonia, 800-1200 ppm of methanol and minor concentration of other chemicals. All these are stripped and in the best practices the condensate is recycled. The heat released during cooling/condensation is used for: regeneration of CO2, scrubbing solution.

Brief on Ammonia

production from Natural Gas -

The amount of heat released depends on the process steam to carbon ratio. If all this low level heat is used for CO2 removal or absorption refrigeration, high-level heat has can be used for feed water system. An energy-efficient process should therefore have a CO2 removal system with low heat demand. The CO2 is removed in a chemical or physical absorption process. The solvents used in chemical absorption process are mainly aqueous amine solutions Mono Ethanolamine (MEA), activated Methyl DiEthanolamines (aMDEA) or hot potassium carbonate solutions. Residual CO2 content are usually in the range 100-1000 ppmv, depending on the process used. Contents of CO2 down to 50 ppmv are achievable. 6) Methanation (not in all plants) The small residual amount of CO and CO2 in the synthesis gas, are poisonous for the ammonia synthesis catalyst and must be removed by conversion to CH4 in the methanator : CO + 3H2 = CH4 + H2O CO2 + 4H2 = CH4 + 2H2O The reaction takes place at around 300 °C in a reactor filled with nickel containing catalyst. Methane is an inert gas but water must be removed before entering converter. 7) Synthesis Gas Compression and Ammonia Synthesis Modern ammonia plants use centrifugal compressors for synthesis gas compression, usually driven by steam turbines, with steam being produced within the ammonia plant from exothermic heat of reactions. The refrigeration compressor, needed for condensation of product ammonia, is also driven by a steam turbine. The synthesis of ammonia takes place on an iron catalyst at pressure usually in the range of 100- 250 kg/cm2 and temperatures in the range of 350-550 °C: N2 + 3H2 = 2NH3 Only 20-30% of synthesis gas is converted to ammonia per pass in multi bed catalyst filled the converter due to the unfavorable equilibrium conditions. The ammonia that is formed is separated from the product gas mixture by cooling/ condensation, and the unreacted gas is recycled with the addition of fresh make up synthesis gas, thus maintaining the loop pressure.

Brief on Ammonia

production from Natural Gas -

In addition, extensive heat exchange is required due to exothermic reaction and large temperature range in the loop. Conventional reforming with methanation as the final purification step, produces a synthesis gas contains inerts (Methane and argon) in quantities that don‘t dissolve in the condensed ammonia. The major part of these is removed by taking out a purge stream from the loop. The size of this purge stream controls the level of inerts in the loop to about 10-15%. The purge gas is scrubbed with water to remove ammonia before being used as fuel or before being sent to hydrogen recovery unit. Ammonia condensation is far from complete if cooling is with water or air and is usually not satisfactory. Vaporizing ammonia is used as a refrigerant in most ammonia plants, to achieve sufficiently low ammonia concentration in the recycled gas. The ammonia vapours are liquefied by compression in the refrigeration compressor. The process described is shown in the following Block flow diagram.

phosphate determination A Quantitative method to determine the amount of phosphate present in samples such as boiler feedwater is as follows. A measured amount of boiler water is poured into a mixing tube and ammonium heptamolybdate reagent is added. The tube is then stoppered and vigorously shaken. The next step is to add dilute stannous chloride reagent, which has been freshly prepared from concentrated stannous chloride reagent and distilled water, to the mixture in the tube. This will produce a blue color (due to the formation of molybdenum blue) and the depth of the blue color indicates the amount of phosphate in the boiler water. The absorbance of the blue

solution can be measured with a colorimeter and the concentration of phosphate in the original solution can be calculated. Alternatively, a direct (but approximate) reading of phosphate concentration can be obtained by using a Lovibond comparator. This method for phosphate determination is known as Deniges' method.A simple Qualitative method to determine the presence of phosphate ions in a sample is as follows. A small amount of the sample is acidified with Concentrated Nitric Acid to which a little ammonium molybdate is added. The presence of Phosphate Ions is indicated by the formation of a bright yellow precipitate layer.

Rate of Reaction: The rate of a reaction is the speed at which a reaction happens. If a reaction has a low rate, that means the molecules combine at a slower speed than a reaction with a high rate. The rate of reaction, r, is defined to be the slope of the concentration-time plot for a species divided by the stoichiometric coefficient of that species. Additionally, if the species is a reactant, the negative value of the slope is used, because the slope is negative and a positive rate is desired. For the example shown above rate of reaction = r =-∆[A]/∆t aA + bB → cC + dD Rate = k [A]^a [B]^b

Urea is a white dry organic compound and a crystalline substance and has minimum of 46% Nitrogen calculated in dry state. This has the melting point of 132 deg F. Urea is made by reacting carbon

dioxide (CO2) with anhydrous ammonia (NH3) under pressure of 3000 psi and temperatures of around 350 deg F. Water is removed during processing and the molten matter is either converted to prills or into granules.

Urea PRODUCTION

1. Ammonia pumping : Liquid ammonia is pumped from the multistage pump which maintain the reaction pressure in the vertical stainless steel vessel 2. Carbon dioxide compression: ammonia plant directly boost the carbon dioxide from the compression section as it readily form at the CO2 section of ammonia production plant. 3. Urea synthesis tower: It is lined with film of oxides to protect form corrosion. Catalyst bed is placed in the inner side of the autoclave structure and 180- 200 atm pressure at temperature about 180-200 deg centigrade is maintained. Plug flow operation take places and molten urea is removed from the top of the tower. 4. Distillation tower and Flash drum: This high pressure slurry is flashed to 1 atm pressure and distilled to remove excess ammonia and decomposed ammonia carbamated salts are removed and recycled. 5. Vacuum Evaporator: The solution is fed to vacuum evaporator for concentrating the slurry. 6. Prilling Tower: It is dryer where the molten slurry is passed from top of the tower into a bucket which rotates and sprinkles the slurry and air is passed from the bottom. All the moisture is removed as the urea form into granules during it journey to the bottom of the tower. This granules are sent by conveyor to the bagging section.

Vacuum distillation in petroleum refining: Petroleum crude oil is a complex mixture of hundreds of different hydrocarbon compounds generally having from 3 to 60 carbon atoms per molecule, although there may be small amounts of hydrocarbons outside that range.The refining of crude oil begins with distilling the incoming crude oil in a so-called atmospheric distillation column operating at pressures slightly above atmospheric pressure.In distilling the crude oil, it is important not to subject the crude oil to temperatures above 370 to 380 °C because the high molecular weight components in the crude oil will undergo thermal cracking and form petroleum coke at temperatures above that. Formation of coke would result in plugging the tubes in the furnace that heats the feed stream to the crude oil distillation column. Plugging would also occur in the piping from the furnace to the distillation column as well as in the column itself.he constraint imposed by limiting the column inlet crude oil to a temperature of less than 370 to 380 °C yields a residual oil from the bottom of the atmospheric distillation column consisting entirely of hydrocarbons that boil above 370 to 380 °C. To further distill the residual oil from the atmospheric distillation column, the distillation must be performed at absolute pressures as low as 10 to 40 mmHg (also referred to as Torr) so as to limit the operating temperature to less than 370 to 380 °C.The 10 to 40 mmHg absolute pressure in a vacuum distillation column increases the volume of vapor formed per volume of liquid distilled. The result is that such columns have very large diameters.

Covalent Functionalization of Graphene with Reactive Intermediates: Graphene, a material made exclusively of sp2 carbon atoms with its π electrons delocalized over the entire 2D network, is somewhat chemically inert. Covalent functionalization can enhance graphene‘s properties including opening its band gap, tuning conductivity, and improving solubility and stability. Covalent functionalization of pristine graphene typically requires reactive species that can form covalent adducts with the sp2 carbon structures in graphene. In this Account, we describe graphene functionalization reactions using reactive intermediates of radicals, nitrenes, carbenes, and arynes. These reactive species covalently modify graphene through free radical addition, CH insertion, or cycloaddition reactions. Free radical additions are among the most common reaction, and these radicals can be generated from diazonium salts and benzoyl peroxide. Electron transfer from graphene to aryl diazonium ion or photoactivation of benzoyl peroxide yields aryl radicals that subsequently add to graphene to form covalent adducts. Nitrenes, electron-deficient species generated by thermal or photochemical activation of organic azides, can functionalize graphene very efficiently. Because perfluorophenyl nitrenes show enhanced bimolecular reactions compared with alkyl or phenyl nitrenes, perfluorophenyl azides are especially effective. Carbenes are used less frequently than nitrenes, but they undergo CH insertion and C═C cycloaddition reactions with graphene. In addition, arynes can serve as a dienophile in a Diels–Alder type reaction with graphene. Further study is needed to understand and exploit the chemistry of graphene. The generation of highly reactive intermediates in these reactions leads to side products that complicate the product composition and analysis. Fundamental questions remain about the reactivity and regioselectivity of graphene. The differences in the basal plane and the undercoordinated edges of graphene and the zigzag versus armchair configurations warrant comprehensive studies. The availability of welldefined pristine graphene starting materials in large quantities remains a key obstacle to the advancement of synthetic graphene chemistry.

Synthesis of carbide-derived carbon by hydrothermal decomposition: The removal of metal atoms from carbides has been reported at high temperatures (300–1000 °C) and pressures (2–200 MPa). The following reactions are possible between metal carbides and water: x/2•MC + x•H2O → Mx/2Ox + x/2•CH4 MC + (x+1)•H2O → MOx + CO + (x+1)•H2 MC + (x+2)•H2O → MOx + CO2 + (x+2)•H2 MC + x•H2O → MOx + C + x•H2 Only the last reaction yields solid carbon. The yield of carbon-containing gases increases with pressure (decreasing solid carbon yield) and decreases with temperatures (increasing the carbon yield). The ability to produce a usable porous carbon material is dependent on the solubility of the formed metal oxide (such as SiO2) in supercritical water. Hydrothermal carbon formation has been reported for SiC, TiC, WC, TaC, and NbC. Insolubility of metal oxides, for example TiO2, is a significant complication for certain metal carbides (e.g., Ti3SiC2).

Glycol dehydration units or TEG dehydration units are the most economical type of natural gas dehydration where dew points depressions of 60° to 120°F are required. Triethylene glycol (TEG) is the most common type of glycol use for gas dehydration. In the glycol dehydration process TEG is pumped to the top of a contactor tower where it is flow countercurrent with wet gas flowing up the tower, utilizing internal high efficiency structured packing for larger gas flows, or trays for smaller tower sizing, for efficient gas/liquid contacting. The TEG adsorbs water from the wet gas and is passed to the glycol regeneration unit where, very simply, adsorbed gases are flashed off and the water is removed from the reboiler by heating the wet glycol to around 400ºF at atmospheric conditions. The regenerated TEG is then pumped back to the contactor tower inlet.

Water Treatment Plant: 1 Intake Crib Raw water from a surface water lake or reservoir is drawn into the plant through intake structures. Large debris like logs are prevented from entering and zebra mussel control is performed at the intake. 2 & 3 Screens Smaller debris like fish, vegetation and garbage are removed from the raw water by protective bar and travelling screens before the water enters the low lift pumps. 4 Low Lift Pump Well These pumps lift the water to flow through the treatment processes by gravity. 5 Pre-oxidation & Primary Disinfection Disinfectants or other oxidants are added to disinfect or control tastes and odours. The specific processes used are determined by the chemical and biological raw water characteristics.

Water Treatment Plant: 6 Coagulation Coagulants, rapidly add electrochemical charges that attract the small particles in water to clump together as a ―floc‖. This initial charge neutralization process allows the formed floc to agglomerate but remain suspended. 7 Flocculation By slower mixing, turbulence causes the flocculated water to form larger floc particles that become cohesive and increase in mass. This visible floc is kept in suspension until large enough to settle under the influence of gravity. 8 Sedimentation Flocculated water is applied to large volume tanks where the flow speed slows down and the dense floc settles. Settled floc is removed and treated as a waste product that is discharged to the sewer system. 9 Media Gravity Filtration Relatively floc free, settled water flows through a media filter by gravity. Filter media are made from layers of anthracite or granular activated carbon and sand. Gravel or synthetic materials support the media. Physical straining removes the remaining floc. Filters are periodically backwashed to clean off accumulated floc and other trapped impurities. 10 Clear Well Filtered water in the clear well is used to backwash filters and kept in storage to ensure that disinfectants are in contact with the water long enough to inactivate disease causing organisms. 11 Secondary Disinfection Supplemental chlorine is added to maintain disinfection concentrations while the water is pumped through the distribution system. The purpose is to ensure minimum residual disinfectant levels at the farthest points of the system. 12 Fluoridation A process where silicofluoride compounds are added to treated drinking water to artificially raise the fluoride concentration to within a specified range; for example between 0.5 to 0.8 mg/L (ppm). Fluoridation is an optional public health dental policy.

Water Treatment Plant: 13 High Lift Pump Well Treat drinking water is pumped through large pressure pumps to other pumping stations, reservoirs or points of supply within the local distribution system. 14a & 14b Elevated Water Storage Towers and Ground Level Reservoirs Water distributed to water towers and storage reservoirs ensures stable water pressure. An adequate supply of water is maintained to meet peak water demands or emergencies such as fires, water main breaks, power outages and pump failures. Distribution System Distribution systems are comprised of large pipes known as trunk mains to deliver drinking water. Smaller diameter branch mains feed individual streets. Service connections to branch mains deliver water into residences. Pumping stations are used to increase pressure and to maintain adequate supply flows.

A steam ejector is a type of pump that uses the Venturi effect of a converging-diverging nozzle to convert the pressure energy of a motive fluid to velocity energy which creates a low pressure zone that draws in and entrains a suction fluid. After passing through the throat of the injector, the mixed fluid

expands and the velocity is reduced which results in recompressing the mixed fluids by converting velocity energy back into pressure energy. The motive fluid may be a liquid, steam or any other gas. The entrained suction fluid may be a gas, a liquid, a slurry, or a dust-laden gas stream.

Heat is transferred by one of these three modes - conduction, convection and radiation.

1) Conduction is the method of transferring heat by contacting directly with other objects. The mechanisms involved in conduction are the transfer of free electrons and energy passing between molecules of contacting objects by lattice vibration. Good conductors of heat are silver copper, iron and steel. Air and papers are poor heat conductors.

2) Convection is the method of transferring Heat by convection current formed by up and down movement of fluids particles. This occurs because the decrease in density as the result of the increase in temperature. For example, forced current convection by heater rise hot air balloons.

3) Radiation occurs when heat is transferred in empty space by electromagnetic wave. For example, the sun warms the Earth through the radiation of EM wave. Taking the arrangement of atoms and frequency of particle collisions into account, conduction therefore is faster than convection. Newton's law of cooling and StefanBoltzman Law are related to heat transfer.

why protons will not repulse each other in nucleous? It's just that the mass deficit creates the nuclear binding energy (or nuclear glue) through residual strong interaction (strong force) that overcomes the coulomb force that's trying to push the nucleus apart and keeps it together. The electrostatic repulsion between protons doesn't just disappear when nucleons are fused together to make heavier atomic nuclei. We can see the electrostatic force pushing atomic nuclei apart as we look at the top of the periodic table. When we synthesize heavier and heavier elements in the physics lab, they are more and more reluctant to "stay together" and stabilize. And we finally reach a point where we just can't force a super heavy nucleus to even begin to stick together. Not even for the tiniest fraction of a second. Because they are positively charged and like charges repel each other.

BLOWERS Blowers develop little higher pressure in comparison to fans. They are used for pressure below 1.65 Psi. The centrifugal blower produces energy in the air stream by the centrifugal force and a velocity to the gas by the blades. The scroll shaped volute diffuses the air and creates an increase in the static pressure by reducing the gas velocity.

FANS The performance of a centrifugal fan varies with change in conditions like temperature, speed and density of the gas being handled. Corrections must be applied to manufacturing standards with respect to operating conditions.

A non-Newtonian fluid is a fluid whose flow properties differ in any way from those of Newtonian fluids. Most commonly the viscosity (resistance to deformation or other forces) of non-Newtonian fluids is dependent on shear rate or shear rate history. However, there are some non-Newtonian fluids with shear-independent viscosity, that nonetheless exhibit normal stress-differences or other non-Newtonian behaviour. Many salt solutions and molten polymers are non-Newtonian fluids, as are many commonly found substances such as ketchup, custard, toothpaste, starch suspensions, paint, blood, and shampoo. In a Newtonian fluid, the relation between the shear stress and the shear rate is linear, passing through the origin, the constant of proportionality being the coefficient of viscosity. In a non-Newtonian fluid, the relation between the shear stress and the shear rate is different, and can even be time-dependent. Therefore, a constant coefficient of viscosity cannot be defined. — at A Newtonian and non-Newtonian fluid.

Centrifugal pump: Centrifugal pumps are used to transport fluids by the conversion of rotational kinetic energy to the hydrodynamic energy of the fluid flow. The rotational energy typically comes from an engine or electric motor. The fluid enters the pump impeller along or near to the rotating axis and is accelerated by the impeller, flowing radially outward into a diffuser or volute chamber (casing), from where it exits. it works by:The transfer of energy from the mechanical rotation of the impeller to the motion and pressure of the fluid is usually described in terms of centrifugal force, especially in older sources written before the modern concept of centrifugal force as a fictitious force in a rotating reference frame was well articulated. The concept of centrifugal force is not actually required to describe the action of the centrifugal pump. The outlet pressure is a reflection of the pressure that applies the centripetal force that curves the path of the water to move circularly inside the pump. On the other hand, the statement that the "outward force generated within the wheel is to be understood as being produced entirely by the medium of centrifugal force" is best understood in terms of centrifugal force as a fictional force in the frame of reference of the rotating impeller; the actual forces on the water are inward, or centripetal, since that is the direction of force need to make the water move in circles. This force is supplied by a pressure gradient that is set up by the rotation, where the pressure at the outside, at the wall of the volute, can be taken as a reactive centrifugal force. This was typical of nineteenth and early twentieth century writings, mixing the concepts of centrifugal force in informal descriptions of effects, such as those in the centrifugal pump.

heating value: The amount of heat produced from the complete combustion of a unit of fuel. The higher (or gross) heating value is that when all products of combustion are cooled to the pre-combustion temperature, water vapor formed during combustion is condensed, and necessary corrections have been made - Source.

Hydrogen production most used techniques..

Quadratic equation

take a break

When ALBERT EINSTEIN met CHARLIE CHAPLIN Einstein said, What I admire most about your art, is its universality. You do not say a word, and yet the world understands you. “ It’s true,” replied Chaplin, But your fame is even greater The world admires you, when nobody understands you!

INTRODUCTION Where Pipework is a means of transporting solids, liquids and gases valves are incorporated in the Pipework to facilitate the starting, stopping and diverting of the transportation. Valves are also situated in linework such as steam lines, air lines and water lines, which serve plants and installations with the utilities they require in their operations. GENERAL PRINCIPLES Consider the different type of liquids and gases that flow around plant pipeline. High pressure, Low pressure, Corrosive, Non-Corrosive, Low and High Viscosities and Volatilities. If we understand this, then we can see why so may different types and sizes of valves are in use. Valves are manufactured from Forged Steel, Alloys, Cast Steel, Cast Iron, Brass, Plastics etc, the properties of which limit or determine the service for which they are designed. Most manufactures have certain standards developed for the design, manufacture and testing of all types of valves. The basic dimensional standards such as face to face length, flange and bolt circle dimensions etc, are those of the API or American Petroleum Institute and this has made it possible to interchange various manufacturers valves. VALVE CLASSIFICATION The various types of valve can be sub-divided into the following groups. -

Isolation Valves (Ball, Plug, Butterfly, Gate) Regulating Valves (Globe, Needle and Diaphragm) Check Valves or Non – Return Valves Relief Valves

DESIGN FEATURES OF VALVES VALVE COMPONENT

FUNCTION

Handwheel

Provides a means of operating the valve gate or disc to open and close the valve, the direction of rotation is indicated on the handwheel, this is normally clockwise to close and anti-clockwise to open. In smaller valves of bronze or brass type the handwheel is made of alloy and is easily broken, this is to protect the spindle etc from damage if any great pressure is exerted. The handwheel may be attached to the bush in the yoke or directly to the valve or spindle.

Yoke

This is the joining piece between the two pillars, sometimes know as the bridge or the collar. The yoke may be removable or cast with the pillar and bonnet. It provides even pressure on pillars when handwheel is operated.

Pillars

Brace between bonnet and yoke. They may be the removable type held in position with nuts,or the permanent type which are cast with valve bonnet.

Stem and Spindle

Provides a means of operating the gate or disc to open and close the valve. The gate or disc being attached to the stem which passes through the bonnet via the stuffing box. The upper or external part of the stem may be threaded and is know as the spindle, this part is operated by the handwheel. Spindle may be rotated or just raised and lowered, depending on the type of stem operation, these will be discussed later. Spindle has square thread for greater strength.

The Gland may be held in position and adjusted by two nuts and bolts, if so adjustments must be made evenly to prevent gland binding on the stem and to ensure packing is pulled down evenly. On smaller valves the gland is held in position with one nut through which the stem passes, this nut screws direct onto the outside of the stuffing box. Stuffing Box

Provides a means of passing the valve stem through the bonnet to operate the shut off mechanism and prevent any leakage of fluid when packing is added. It is normally incorporated in the bonnet construction, in smaller valves it can be a separate part screwed onto the bonnet.

Body

Provides a means of channelling the liquid or gas, from the inlet to outlet port, via the shut off mechanism, which is normally in the shape of a disc. The body is actually the valve casing, to which connections are made to pipelines, etc, the ports may be of the flanged, screwed or welded type.

Bonnet

Valve cover, this enables the internals of the valve to be removed for servicing, it may be a flange type, this is normal for valves above 2”. For smaller valves it may be a screw type, in this case it is in the form of a large nut. At extremes in temperature high/low extended bonnet valves are used.

Seat

Forms a seal with the gate or disc to prevent fluid flow when valve is closed. There may be one or two seats in a valve, depending on the type of shut off mechanism, It is in the shape of a ring and screwed into the body, enabling valve seats to be renewed when badly scored. The face is a machine surface to form a good seal with the gate or disc. In smaller cheap valves, the valve seat may be part of the body and not removable, but in larger and more expensive valves seats are always removable.

Bush

Installed in the yoke. Inside the bush is threaded to match spindle, ie. Square thread. The bush may be free to rotate or fixed, depending on the type of stem operation.

Gland and Bush

The gland sometimes referred to as the gland follower, holds the packing in position inside the stuffing box. By tightening the gland, the gland bush enters further into stuffing box squeezing the packing down, this causes it to expand and form a seal agai

Gate and Discs

Forms a seal with the valve seat when in the closed position. It is attached to the stem of the valve and can be raised to open or lowered to close. The gate or disc may be in the vertical or horizontal position depending on the type of valve.

The basic concept of the ball valve is the use of spherical ball-plug held between tow lip seal seats. The seats are made from a choice of various synthetic material such PTFE butadiene-acrylonitrile rubber and a special nylon variant. The inside diameter of this lip is always slightly larger than the ball-port so that no “growth” of the seal occurs to prevent operation. Tolerances are controlled so that a predetermined deflection of the lip seal occurs during assembly, thus giving intimate contact, irrespective of line pressure. The metal ball closure member is usually hard chrome-plated, both to resist abrasion and to give long life. Ball valves are usually manufactured in sizes of ¼” to 8”. Materials of construction of the main valve assembly are chosen for the design duty of the valve, such as cast iron, ductile iron, bronze, aluminium, carbon, stainless steel, titanium, zirconium, tantelum, and many corrosion resisting alloys and plastics. Pressure ratings are as high as 7,500 p.s.i. and temperatures ordinarily up to 575ºF. OPERATION OF BALL VALVES The Ball Valve has always been considered on of the most efficient type of valve because it provides an unrestricted throughway, ease of operation, and minimum weight. Operating is by means of a shouldered stem which engages in a slot in the ball. By operating the lever, the ball plug is rotated so that its port is in line with the body ports or at right angles to body ports, ie. Closing them off and preventing any flow. Some of the outstanding features of the double seal ball valve are as follows: Complete shut off The well designed lip seals on the flexible seats deflect under pressure and follow the contour of the ball in the absence of pressure, ensuring a dead tight seal in both directions of flow.

Minimum maintenance The seats are self-acting and pressure energised, thus requiring no adjustment or attention in service. The valve requires no lubrication and only infrequent attention to the gland. Very compact size It requires very little head-room and can be sited at any angle. Round bore straight-through flow Produces exceptionally low pressure drop with almost negligible turbulence. Two-way sealing The design of the seat is such that line pressure forces the upstream seat on to the ball and the ball on to the downstream seat, thus providing a “Double Seal” ball valve.

COCKS AND PLUG VALVES Cocks Cocks are the simplest form of all closure devices, giving on – off and throttling position for flow control. In its simplest form the cock consists of a taper plug capable of rotation in an enveloping barrel or body. Cocks do not incorporate the design features peculiar to plug valves for reducing the friction between the plug face and body seat. Cocks are suitable for low pressure service on cold liquids, or low pressure air or steam in its elementary form and of small bore, the principle can be employed for very high hydraulic pressures with careful attention to design. Cocks are generally used for controlling low pressure water, oil, acids (with due regard to materials of construction) slimes, tars of anything that will flow, but care should be exercised if contemplated for steam use and they should never be used on superheated steam. Cocks will often meet an application more effectively than an elaborate screw-down stop valve. One outstanding advantage of the cock is that multiport flow can be arranged. Types of Cock Plug cock

A taper-seated cock in which the plug is retained in the body by means of a washer, screw and nut at the smaller end of the plug.

Gland Cock

A taper-seated cock in which the plug is retained in the body by means of a gland and gland packing.

Compound Gland Cock

A cock in which the plug is retained in the body by the cover, the stuffing box being formed in the cover.

Packed Cock

Any type of cock in which packing material is inserted to effect a seal between the plug face and the body seal.

Plug Valves A form of shut-off device, having a plug, either parallel, taper or spherical in shape, which can be turned to move its port or ports relative to the body seal ports to control the flow of fluid and which incorporates design features which reduce friction between the plug face and the body seat during the turning of the plug and/or seal them against leakage. The plug is a refinement of the simple cock, suitable for high pressure and temperatures. A ¼ turn opens or closes the valve. Flow through the valve is smooth, straight and uninterrupted. Pressure drop across the valve is therefore low. Seating surfaces are fully protected from the line fluid. In addition to straightway designs, multiport, and steam jacket types are available. In lubricated plug valves, the seating surfaces of the plug and its enveloping barrel or body are lubricated. The lubricant being in stick or cartridge form and introduced into the head of the plug and forced through appropriately located ducts and grooves which eventually communicate with the seating surfaces of the valve. The lubricant is forced through these ducts with the aid of a screw or gun in conjunction with a small ball check valve to prevent return flow. This pressure lubrication performs four important functions:i) ii) iii) iv)

it provides a jacking action it seals the valve it minimises friction and wear it protects the seating surface from corrosion and erosion

Types of Plug Valve Lubricated plug valve

A plug valve which incorporates design features whereby lubricant is injected under pressure between the plug face and body seats.

Non-lubricated plug valves

A plug valve which incorporates Mechanical design features to reduce the friction between the plug face and body seat during turning of the plug. The most common type is: Lift plug valve in which mechanical means are provided to lift the plug from the body seat during turning of the plug.

A butterfly valve consists of a housing in which a shaft passes through. On this the vane and valve plate are connected. The top of the housing can adapt various types of shaft actuators, both power or manually operated. Power, lever and handwheel actuators are interchangeable without additional parts. The actuator is connected on the end of the shaft. The valve is in the fully open or closed position by turning the actuator 90 angular degrees. To prevent deflection there are bearing built-in at both ends of the shaft. When the valve is in the wide open position, there is a straight-through flow with only the small area of the edge-wise surface of the plate and vane causing an obstruction. A lever actuator valve for manual operation has a scale for indicating the vane position and integral stop at each end of the scale. A plate-plunger pin located on a squeeze type level assembly engages the plate which is notched for on-off operation. The packing at both ends of a one-piece shaft eliminates unbalanced forces on shaft due to static pressure and resultant vane misalignment problems. A grease asbestos type of packing is normally used to sea-off leakage through the gland. Butterfly valves are multi-purpose valves and are applicable to rather low pressures, say up to 10 kg/cm2. They are characterised by their large capacity and are less expensive than plug or globe valves.

HAND WHEEL LOCK PIN

BONNET

OPERATING MECHANISM

COMPRESSOR AND FINGER PLATE

BODY

FLEXIBLE DIAPHRAGM STREAMLINE PASSAGE

LINED INTERNALLY

SEAT

This is valve is used on a large scale in the chemical industry where a large amount of corrosive material is handled. Diaphragm valves were first developed for compressed air duty nowadays has a very wide and important range of duties for the control of fluids. The diaphragm isolates the operating mechanism in the bonnet assembly from the fluid being handled. This isolation preserves the lubricated part from possible damage by abrasive or corrosive fluids and is equally effective in preventing contamination of pipe contents. Diaphragm valve bodies and diaphragms are available in a very wide range of material to suit any of more than 700 fluids. Diaphragm valves are made in different designs for different types of service and can be equally effective for liquids, slugs, slurries, pulps or fluids containing solid matter in suspension. Diaphragms are now manufactured to suit temperature conditions ranging from -85°F to 392°F ( -65°C to 200°C). Even certain steam services can be tackled subject to pressure limitations. Diaphragm valves find a wide use in chemical engineering. Diaphragm valves consist of a mechanism, which enables a diaphragm to be screwed down onto a seat by means of a so-called compressor. The flexible diaphragm isolates the operating mechanisms from the liquid flowing through the valve and therefore there is no gland. Two diaphragms are used and the most common ones used on the chemical plants are Teflon and rubber. The outer portion of the diaphragms also forms the body to bonnet joint, thus sealing off the fluid from the moving parts. Teflon is normally the diaphragm in contact with the fluid, the rubber being topside of this against the compressor.

Operation The stem action of these valves is normally inside screw, non-rising stem, where the handwheel is attached to a non-rising stem, which is attached to a finger plate mounted in the valve for guidance of the compressor, the compressor and diaphragm rising on the stem when the valve is opened. The operation of this valve is simple the handwheel is rotated to close the valve, this forces the compressor to which the diaphragm are attached on to the weir at the base of base of the valve, thus sealing off the fluid. Summarising the diaphragm valves has the following features: a) b) c) d)

flexible diaphragm absence of gland operating mechanisms insulated from fluid stream a streamline flow

The bodies of these valves can be made from a variety of materials. Finally, it is easy to line the valve internally in order to increase chemical or abrasion resistance.

These valves are widely used where uninterrupted flow is required and are suitable for general purposes on such services as steam, water, oil, gas and many other fluids. They should not be used in throttling service and should only be used either fully open or fully close. A gate valve provides a straight through passage for the flow of fluid. The body ends are in line and the gate is moved between the body seats by a stem whose axis is at right angles to that of the body ends. Gate valves may be: a)

Inside screw i)

b)

In which the actuating thread of the stem is contained inside the valve. This may take three forms: Inside screw, rising stem, where the handwheel is attached to a non-rising stem, the gate rising on the stem when the valve is opened.

ii)

Inside screw, non-rising stem, where the handwheel is attached to a non-rising stem, the gate rising on the stem when the valve is opened.

iii)

Inside screw, rising spindle, rising stem, where the handwheel is attached to a rising spindle, and the stem rises within and with the spindle when the valve is open.

Outside screw i)

In which the actuating thread of the stem is exterior to the bonnet. This may take three forms: Outside screw, stem rising with handwheel. Where the handwheel is attached to the stem and rises with it when the valve is opened.

ii)

Outside screw, stem rising through handwheel. Where the handwheel is attached to a yoke sleeve or bridge and through which the stem rises when the valve is opened.

iii)

Outside screw, non-rising spindle, rising stem. Where the handwheel is attached to a non-rising spindle and the stem rises when the valve is opened.

Types of Gate Valve Wedge Gate Valve -

a) b)

A valve in which closure, ie. Affected by the wedge action between the gate and body seats. A wedge gate valve may take the following forms:

Solid wedge - In which the gate is in one piece, either solid or cored. Split wedge - In which the gate is in two pieces.

The solid wedge disc has the advantage of strength and being a single part, is not liable to vibrate or chatter in service, thereby reducing wear to a minimum. The solid wedge gate valve can be installed in any position without danger of the disc jamming due to misalignment of parts. Soft-seals can be installed in solid wedge gate valves, these comprise of nonmetallic rings which are fitted in the body seats, or in the wedge, giving tight closure backed by contact of metal-to-metal surfaces for searching and corrosive fluids. Double Disc Gate Valve - A valve in which the gate consists of two discs which are forced apart by a spreading mechanism at the pont of closure against both parallel body seats, thus ensuring an effective sealing of the valve without the assistance of the fluid pressure.

Parallel Slide Valve - A valve in which the gate consists of one or two discs, without spreading a mechanism, which slide between parallel body seats, effective closure being obtained by the fluid forcing the downstream disc face against the body seat. HOPKINSONS PARALLEL SLIDE VALVE The merits of parallel slide valves have been recognised as a general purpose stop valve and for conditions where the flow through the valve may be in either direction. It is usually used as an isolating valve on steam service.

Principle Features of the Parallel Slide Valve Action:

The outstanding feature of this valve is that it Achieves shut off without the aid of wedging action. No mechanical stress is exerted between the discs and the valve is not subjected to dangerous strains in opening or closing. A light spring keeps the discs in close contact with the seats when the valve is not under pressure. When the valve is closed and under pressure the disc at the outlet is held in contact with its seat by liquid or vapour pressure. When the valve is being opened, the discs slide over the seat faces until completely clear of the bore, thus giving and unobstructed passage through the valve and reducing pressure drop to a minimum. The slide valve action also removes any dirt and foreign matter the faces.

IDENTIFICATION

Muliturn Valve That Effects Closure By Means Of One Or More Flexible Elements, Such As Diaphragms Or Rubber Tubes ,That Can Be Passed Together To Cut Off Flow.

RECOMMENDED

1- For On-off Service. 2- For Throttling Service. 3- For Moderate Temperatures. 4- Where Pressure Drop Through Valve Is Low. 5- For Services Requiring Low Maint.

APPLICATIONS

1- Slurries, Mining Slurries, 2- Liquids With Large Amounts Of Suspended Solids, 3- Systems That Covey Solids, 4- Foods, And 5- Pharmaceuticals.

ADVANTAGES

1- Low 2- Low Maintenance. 3- No Internal Obstruction Or Pockets To Cause Clogging. 4- Non Corrosive And Abrasion- resistant Cost 5- Simple Design.

DISADVANTAGES

1- Limited Vacuum Application 2- Difficult To Size.

VARIATIONS

1- Exposed Sleeve Or Body, 2- Encased Metallic Sleeve Or Body

MATERIALS

Rubber, White Rubber Hypalon, neoprene, Whit Neoprene Bunna-n, Bunna-S Viton-A, Silicon, TFE

SPECIAL INSTALLATION AND MAINTENANCE INSTRUCTIONS

Large Sizes May Require Supports Above Or Below The Line If Pipe Supports Are Inadequate.

ORDERING SPECIFICATIONS

1- Sleeve Material 2- Exposed Or Encased Sleeve 3- Operating Pressure. 4- Operating Temperature.

INTERNAL BELLOWS SEAL GATE AND GLOBE VALVES These valves are unique in design having a built in internal bellows seal designed so that the process pressure is applied externally on the bellows this combined with the compression/decompression action of the bellows when opening or closing the valve forms a positive seal within the valve body, conventional gland packing is provided to give a secondary seal system. These valves are normally used on steam tracing. Steam is very searching and a wire drawing effect is caused on any surface across which it is escaping, the bellows assembly eliminates this problem. NOTE: The gate valve spindle stays approximately ¼ proud when the gate is fully closed against the seat. It can be seen from the points discussed that the gate valve is simple but effective, one of the main advantages is the very low pressure drop when the valve is fully open, this being due to the straight through passage.

HAND WHEEL

VALVE POSITION INDICATOR

SPINDLE

BODY

BRIDGE FLANGE

DISC SEAT

NEEDLE VALVES Needle valves consist of housing in which a sharp pointed needle plug passes through the gland and can be screwed down on its seat. A screw type of gland may be applied to screw the teflon or asbestos packing into the gland stuffing box. This is to seal off leakage of gas or liquid along the spindle. A screw cap is used to prevent dirt getting into the tread of the gland. A needle valve has the same principle characteristics as the globe valve and is mainly used to control small amounts of gas or liquid flows through the valve. It is normally used on gas sample cylinders and also on by-passes of gas or chemical injection pumps. This valve is seldom operated in fully-open position, but basically only for throttling purposes. These are normally used where the flow has to be controlled at fine limits. There are two types of needle valve: i)

Straight through flow - process control

ii)

90 Angle Type - generally used on gas cylinders for sampling gas/liquid streams.

OBLIQUE OR KESTNER GLOBE VALVE Is a valve generally having a spherical body in which the body ends are in line with each other and in which the axis of the stem is oblique to that of the body ends. Mainly used on highly corrosive duty.

Form the points discussed, it can be seen that a screw-down stop valve creates a higher-pressure drop than a gate valve, this is due to the construction and up and over flow of the fluid through the valve. It has been found that these valves give better isolation than gate valves but these valves should not be chosen just for this reason, remember the increased pressure drop. The main advantage of this valve is the control of flow, nearly all control valves will be found to have this type of body and valve seating, with slight modifications. The following chart will give some ideas of comparison in pressure drop between gate valves and globe valves. For example a 2” gate valve wide open is equivalent to adding 1-ft pipe. If this were changed to a globe valve in the wide-open position, it would be equivalent to adding 54 ft of piping. It can be seen that if fitted in pump discharge, etc the pressure downstream of the valve would reduce and could cause further problems. Fitting

Nominal pipe diameter inches 2”

Gate Valve:

2 ½”

3”

4”

6”

8”

10”

12”

Length of feet of pipe to be added

¾ closed

140

165

200

280

400

540

700

800

½ closed

33

38

50

65

100

130

160

190

¼ closed

7

8

10

13

19

26

33

39

Open

1

1

2

2

3

4

6

7

Globe valve open

54

62

82

110

170

220

288

330

Angle valve open

27

32

41

55

82

110

140

165

Ball plug valve

9



11½

22

36

42

CONTROL AND NON-SHUT OFF VALVES PNEUMATIC AUTOMATIC CONTROL VALVES Valves of the type shown are used in process plants for the automatic control of flows, levels, pressures and temperatures by changing the opening of the valve, and thus the flow through it. A control valve consists of an operator and a valve body. The operator provides the power to vary the position of the valve plug inside the body. The valve body is a pressure-tight fitting, screwed or flanged to the process line. The moveable plug serves to control the net flow area through this valve. The plug is connected to the operator by a stem, which slides through a stuffing box. The equipment which measures the flow, level, pressure, or temperature being controlled sends out an air pressure signal, which varies usually in the range 3 to 15 p.s.i. The air signal is applied above the diaphragm. An increasing air signal will push the operator stem downwards against the force exerted by the spring on the diaphragm plate. As a result of the downward movement, the net area through which the flow passes will decrease gradually. The plug starts moving when 3 p.s.i. is applied to the diaphragm, and touches the seat when 15 p.s.i. is applied. An increase in air pressure is required to close the valve and a reduction to open the valve hence the name “Air off to open” (AFVO). The plug is constructed so that it can be removed from the valve stem, and refitted in reverse. The body can also be reversed. The action of the valve is thus reversed Air failure valve open (AFVO) or air failure valve closed (AFVC) are selected following consideration of plant requirements so that valves “fail safe” in event of air failure. This reversal is sometimes accomplished by fitting the spring on top of the diaphragm and introducing the air signal to the underside of the diaphragm.

The valve is double-seated so that the static pressure and dynamic axial forces on the valve plug are balanced. This reduces the forces to be overcome by the operator to frictional resistance in the gland. However, with double-seated valves, a complete shut-off is impossible, and this must be accomplished by a “back-up” valve. The gland packing on the valve stem is frequently lubricated using a special lubricator, which introduces grease under pressure into the gland through a lantern ring. Single Seat Control Valves Single seat valves are sometimes used in small sizes, or where an absolute shut off is required.

MOTORISED GATE VALVE The motorised valves are basically identical to the manually operated valves, except that the operation of opening and closing the valve is now performed by a motor.. The motor is built integrally with the handwheel and is connected via a worm gear drive to the valve spindle. Torque or speed characteristics are carefully matched. Interchangeable motors give a wide range of output speeds. When the electric power is available the motor takes over the function of the handwheel or any other type of manually operated device. However, when power is off the auto lever automatically disconnects the drive, so thatthe valve can be hand operated. The actuators (motor plus handwheel) can be applied with an integral reversing motor. The system of control can be operated as package unit (local control) or in the control

SCREWCAP GASKET SPRING

BODY SEAT RING

PISTON TYPE DISK

BODY

CAP GASKET

BALL DISK

BODY SEAT RING

BODY

No. Parts Name No. Parts Name No. Parts Name 6 Seat 1 Body 11 Gasket 7 Stud 2 Disc 12 Body 8 Nut 3 Bolt 13 Support 9 O-ring 4 Nut 14 Bolt O-ring 5 Drain Valve 10 15 Nut

CHECK OR NON RETURN VALVES A check valve in which the check mechanism incorporates a disk, piston or ball which lifts along an axis in line with the axis of the body seat. Lift type check valves are described according to the type of check mechanism, as follows: NOTE: A check or N.R.V. is seldom fully tight – normal isolation procedures should be enforced on suspension of flow

Swing Check Valves are available in straight body design and y-pattern design. The disk is suspended from the body by means of a hinge pin and seals against the seat which is integral with the body. These valves are typically used in sizes 2 inches and over. Swing check valves can be installed in both horizontal and vertical position. They are not suitable for pulsating flow. Closure response of swing check valve is slower compared to lift check valve due to longer disc travel and inertia of disk.

Piston Check valves are generally used to protect pumps or similar equipment, allowing the flow only in one direction and preventing flow reversal due to back pressure. The piston check valves are designed with globe valve bodies, producing an increased drop pressure in the pipeline. This design provides a tight seal as well as a fast reaction to the closure impulse. Metal seated check valves may not provide drop tight sealing when used in gas system or fluid system with low back flow pressure or fluids containing particles.

The ball check valve is one of the few check valves that works well in both water and wastewater applications. Ball check valves are simple in operation and commonly used on small pumps and in low head systems. Consider adding an optional roll-bar to the piping system for safety; ball check valves have the highest tendency to slam due to the ball's high inertia long stroke. When ball check valves encounter high pressures and dynamics, severe slamming may result.

Tilting Disk Check Valves fit between two flanges and provide a compact installation for large diameter applications. These valves can be installed in horizontal and vertical lines. They provide a quick closing response and are particularly suited for pulsating flows with compressible fluids.

NO PART NAME

NO

PART NAME

1 2 3 4 5

6

L-BOLT (EYE-BOLT) BODY SEAT DISC BEARING

BODY DISC CLAPPER SEAL PIN PLUG

7 8

Wafer Type Check Valve has short face-to-face dimensions and low weight allows a simple space saving installation between the companion flanges. The valves are suitable to mounting between weld neck or slip on type companion flanges of different standards. They are specially developed for applications where a low-pressure loss is essential. Opening and closing of the valve will take place at an extremely low-pressure difference over the valve disc. The eccentric disc shaft combination with the disc seat guarantees a positive shut off returning media. Wafer check valves are becoming the preferred type of check valve for most applications, due to their compact design and relatively low cost.

Single Disc Check Valve (Wafer Type Disc Check Valve) consists of four main components: the body, a disc, a star guide and a spring. The Disc check valves are opened by the pressure of fluid and closed through compression spring as soon as flow stops thus preventing reverse flow. The design of Wafer Design, Sandwich Type Single Disc Spring Loaded Check Valves allows them to be installed between any flanges of different standard and in any position; including vertical pipelines where the fluid flows downwards.

Dual Plate, Wafer Check Valve employs two-spring-loaded plates hinged on a central hinge pin. When the flow decreases, the plates close by the action of torsion spring before flow reversal takes place. All features put together make the Dual Plate Check Valve as the most efficient & versatile design. It is also referred to as SILENT CHECK VALVE. It is much easier to install between standard gaskets and line flanges, and therefore is more cost effective to install and to maintain. Its design complies with API 594 and API 6D, testing with API 598. It is also called as Butterfly Check Valve.

RELIEF VALVES A relief valve is an automatic pressure relieving device actuated by the static pressure upstream of the valve and which opens in proportion to the increase in pressure over the opening pressure. SAFETY – Guidelines Safety and relief valves are selected for specific duties – and are identified by a reference number on the body tag. A relief valves must only be used on that. They should NEVER be used for any other duty. Locking Isolation Block Valves in the Open Position Safety and relief valves should be installed directly onto equipment they are designed to protect, the discharge routed directly to a vent or vent system capable of handling the maximum discharge flow and released pressure. In some instances block valves have been installed in the upstream and downstream sides of relief valves, the use of these relief valves in stringently controlled. The block valves must be fully open and chain locked or Castell locked in the operating position. Vents Steam systems may have a localised vent pipe on the discharge of the relief safety valve, the pipe aligned vertically. In order to eliminate the build up of condenste in this vent line and consequent increase in the set pressure of the valve, a small hole is drilled into the low point allowing the water to drain. Rust scale can block this hole allowing hot condensate to accumulate, should the relief valve operate this condensate will be blow out creating occasional check should be carried out to ensure the drain hole is not plugged.

POTENTIAL HAZARDS OF INCORRECT VALVE OPERATIONS AND THE STEPS TO AVOID THEM 1.

The operation of valves and pipelines forms a major part of an operator’s task. The following points should be observed if the task is to be done safety and efficiently.

2.

Manual operation is normally done using a handwheel or a handle. Valves should be opened slowly to prevent sudden increases in temperature or pressure, which could damage equipment.

3.

Gate valves should not be used for restricting the flow or throttling flow. The increased velocity can erode the valve.

4.

Valve stem packing must be checked regularly for leakage.

5.

Lubricated valves should be serviced regularly.

6.

Excessive force should not be used to close a valve; otherwise the valve seat could be damaged. Instead open valve a little and try to flush particles that may be resting on the seat.

7.

Non-return valves fail in the open or closed positions. If the valve on the discharge of a pump fails “open” this can cause serious damage to the pump when it is shutdown. In this case and particularly when left on standby, the fluid flow can reverse and cause the pump to rotate in the wrong direction.

The shaft of a standby pump must always be checked to ensure that it is stationary. 8.

Damaged Iagging should be reported for maintenance. Operators should not stand on lagged pipes.

9.

The pipe movement should be checked when bringing a pipe into or out of hot service. Do not allow valve packing to leak as this can erode the valve stem. It can also have a negative environmental impact.

10.

Line heaters should be checked regularly and reported if faulty.

11.

Leaking flanges must be reported immediately. If the leak is bad the pipework may have to be isolated quickly.

12.

Check direction of flow is in line with the markings on the valve. Ease of access to a valve is important.

13.

If the valve is in a difficult location it should be reported.

14.

Care must be taken to ensure that all dirt which may have accumulated in a valve during storage or initial installation is removed by flushing.

15.

Impingement of high velocity fluids carrying abrasive solid particles can cause serious damage.

16.

Always make sure filters remain in line.

17.

Valves that are not operated frequently and may remain open or closed for long periods. Should be moved about once/month.

18.

When gate valves are partially closed they can vibrate causing noise and possible damage. Only use for throttling in an emergency and if needed to be used in this position regularly it should be reported and a more appropriate valve fitted.

19.

Normally valves open by turning the handle wheel in an anti clockwise direction. Normally however direction of rotation is marked on the wheel.

20.

When a fully open position always backoff close a small amount ¼ - ½ turn to stop valve sticking.

21.

Wheel keys can cause high stresses on the valve. They should be used with care.

PREVENTIVE AND ROUTINE PROCEDURES A plant operator is responsible for checking valves and stuffing boxes as well as greasing nipples and gear trains as part of his normal activities. Valves should be checked for: 1)

Excessive nose or vibration,

2)

Fluid passing a valve when it is closed,

3)

Misaligned, bent or broken stems,

4)

Leaking stuffing boxes,

5)

Adequate lubricant,

6)

Cracks and distortions,

7)

Missing or damaged levers or handwheels.

If any of these conditions are observed they should be reported to supervision immediately

take a break

We don't become Engineers, we are born

Engineers.

A valve that controls flow by means of a disk or wedge-shaped dam sliding at right angles to the direction of flow and seating tightly in the valve body is a A. B. C. D.

gate valve butterfly valve globe valve orifice

The equation that relates friction factor and Reynold's No., f=64/Reynold's No. holds for A. B. C. D.

smooth pipes laminar and turbulent flow turbulent flow only laminar flow only

Oil flows under laminar conditions inside a steam heated copper pipe. The overall heat transfer coefficient is approximately A. B. C. D.

equal to the heat transfer coefficient of the oil the average between the heat transfer coefficient of the steam and that of oil equal to the heat transfer coefficient equivalent to the resistance offered by the pipe equal to the heat transfer coefficient of the steam

In multi-stage liquid-liquid extraction with partially miscible solvents A. the extraction must be done to form co-currently in order to minimize the extraction. B. the minimum number of stages occur when the operating lines are parallel. C. the minimum number of stages occur when the tie line coincides with an operating line. D. the amount of solvent used must be enough to form 2 phases.

The enrichment of the vapor steam as it passes through the column in contact with the reflux during distillation is called A. B. C. D.

Evaporation Stripping Rectification Fractionation

The maximum number of plates for a given distillation system is obtained at A. B. C. D.

variable reflux maximum reflux minimum reflux optimum reflux

The correct unit for the specific rate constant for the reaction A--->B determined to be first order is A. B. C. D.

square liter/square mol/min square liter/square mol/square min mol/liter/min liter/mol/min

On one side of a heat exchanger where either a condensing vapor or a boiling liquid is present, the temperature may be assumed to be constant. In determining the logarithmic mean temperature difference the direction of flow will have A. B. C. D.

large effect little effect no effect significant effect

On process plants why are process/utilities connections equipped with flexibles and specific fittings? A. To make sure operator will recognize them B. To prevent any mix of utilities C. To facilitate the work of the operator D. To prevent purging with the wrong utility and/or hydrocarbon contamination

Which of the following is a correction? A. Rework B. Concession C. Deviation D. Scrap

In case of H2S smell Outdoor operator must: A. Try to detect the leak B. Take safety shower C. Start water curtain D. Put escape mask and inform control room

Which of the following is correct? A. Forklift operators hold a specific permit B. Maintenance has a permanent traffic permit C. Inspection is checking the forklift every day D. Forklift speed limit is 40 Km/h

In the case you see a fire the first thing to do is: A. To find foam extinguisher B. To inform control room C. To find a fire hose for watering D. To find CO2 extinguisher

Usage of scaffolding requires: A. A special permit B. Maintenance authorisation C. A safety authorization D. None of the above (neither A, nor B, nor C)

Purging is performed with: A. Air flushing B. Water flushing C. Pressurization/depressurization with nitrogen D. Pressurization/depressurization with CO2

Waste water specifications for release to the environment includes: A. TAH B. NOx C. Viscosity D. COD

Which greenhouse gas is covered by the Kyoto Protocol? A. Nitrogen B. Oxygen C. Hydrogen D. CO2

Which document provides HSE information on chemicals? A. Delivery sheet B. Specification C. Technical bulletin D. MSDS

What is the colour of mandatory signs? A. Blue B. Red C. Yellow D. Black

Why are polymers liquid or solid at ambient condition? A. Because they are thermoelastic B. Because they have a very high molecular weight C. Because polymers are extruded D. None of the above (neither A, nor B, nor C)

Which of the following characterises a polyolefin polymerisation reaction an industrial processes A. It generates heat B. It generates cooling C. All the monomer is consumed immediately D. It is very slow

What is a runaway polymerisation reaction A. A very dynamic plastic B. A reaction starting too early C. An auto accelerating reaction beyond control D. None of the above (neither A, nor B, nor C)

How is the viscosity of a polymer measured A. From its colour B. From the process parameters C. From the amount of polymer flowing in a calibrated hole in a specific time D. None of above (neither A, nor B, nor C)

What is the difference between a volumetric pump and a centrifugal pump? A. Centrifugal pumps are rotating and volumetric are not B. Volumetric pumps are positive displacement pumps C. Centrifugal pumps are positive displacement pumps D. There is basically no difference between the two

How is the flow controlled in a centrifugal pump system A. By throttling the suction valve B. By throttling the discharge valve C. By increasing the suction pressure D. By slowing down the pump

Which one is not correct? A. Reciprocating compressor flow can be adjusted through opening of the machine bypass B. Reciprocating compressor flow can be adjusted through the suction pressure adjustment C. Reciprocating compressor flow can be adjusted by throttling the discharge valve D. Reciprocating compressor flow can be adjusted by cylinder dead volume adjustment

Why is it required to increase the pH of Boiler Feed Water ? A. Because boilers work better at high pH B. Because boilers generate acid at high temperature C. Because pure demineralised water can be very acidic and aggressive if polluted by traces of acid D. Because the boss says so

Why is conductivity preferred to pH to follow Demineralised water quality? A. because demi water pH is always 7 B. because demi water conductivity is easier to measure C. because demi water is good electrical isolator D. because demi water has very low ionic content concentration

Why may additives be used in polymer extrusion? A. In order to improve the transformation characteristics in customers’ machines B. To protect the polymer in applications that are exposed to direct sunlight C. To neutralise the residues in polymers where catalyst residues D. All of the above (A + B + C)

What is observed in a centrifugal compressor if the suction temperature increases (suction and discharge pressure remain constant)? A. Discharge temperature decreases B. Power consumption decreases C. Possible risk of condensing small droplets of liquid at the suction D. All of the above (A + B + C)

What is observed in a turbine if the inlet temperature decreases (suction and discharge pressure remain constant)? A. Discharge temperature decreases B. Power delivered by the turbine decreases C. Possible risk of condensing small droplets of liquid at the discharge D. All of the above (A + B + C)

How can you detect a nitrogen leak? A. By its distinctive colour B. By its characteristic odour C. By the fact that it spontaneously combusts in contact with air D. None of the above (neither A, nor B, nor C)

What is a “double block and bleed”? A. A chronic illness of which operators in the Petrochemical Industry suffer due to incorrect use of Personnel Protective Equipment. B. A method of isolating process circuits prior to carrying out maintenance activities C. A system used by maintenance to carry out lifting operations when a crane is not available D. None of the above (neither A, nor B, nor C)

Nitrogen is often used to remove oxygen in process systems. If a vessel at atmospheric pressure containing 21% oxygen is pressured to 6 barg using nitrogen, what will be the oxygen concentration after this operation? A. 3% B. 3.5% C. 21% D. None of the above (neither A, nor B, nor C)

In solids handling, what is meant by dilute/lean phase conveying? A. A system where the solids to gas ratio is low B. A system which uses water to convey the solids C. A system which uses a mixture of air and water to convey the solids D. A system where the conveying air pressure is very high (above 3 barg)

In a refrigeration loop, what happens if the refrigeration compressor suction pressure is increased? A. No impact on the process fluid being cooled B. The temperature on the process fluid being cooled decreases C. The temperature on the process fluid being cooled increases D. None of the above (neither A, nor B, nor C)

In any polyolefin polymerisation process what will have an impact on the reaction? A. Presence of oxygen B. Presence of water C. Presence of acetylene D. All of the above (A + B + C)

Introduction of an olefin onto a freshly regenerated molecular sieve in a purification vessel without taking adequate precautions could lead to what effect taking place? A. A rapid drop in temperature due to physical absorption of the olefin on the molecular sieve B. A chemical reaction between the molecular sieve material and the olefin C. An increase of temperature due to physical adsorption of the olefin on the molecular sieve D. None of the above (neither A, nor B, nor C) since molecular sieves are totally inert materials

Distillation Quiz Chapter 01: Overview Sub-Chapter 01: About Distillation Distillation is a basic unit operation widely used in oil refineries and petrochemical industries for: A) Raising the process pressure B) Converting the feed into more valuable products by chemical reactions C) Separating products of specific components from a mixture

The feed to a vacuum distillation tower is usually: A) Gasoline from Atmospheric Distillation Unit B) Residue from Atmospheric Distillation Unit C) Jet Fuel from Atmospheric Distillation Unit

Sub-Chapter 02: Tower The distillation tower consists of a series of: A) Reactors B) Trays C) Compressors D) Reboilers

The distillation unit generally consists of a distillation tower, a condenser, a reflux drum and: A) A compressor B) A reboiler C) A turbine D) A reactor

Within a distillation tower, the liquid leaving the tray is __________ in heavier fractions than the vapor leaving the tray. A) Leaner B) Hotter C) Richer D) Colder

Within a distillation tower, the rising vapor is __________ in lighter fractions than the liquid in the tray. A) Leaner B) Hotter C) Richer D) Colder

The bottom product in a distillation tower is: A) Relatively pure in heavier components of the mixture B) Relatively pure in lighter components of the mixture C) Of the same composition as the feed D) None of the above

On each tray, liquid is heated and therefore, some of the liquid vaporizes. This heat is provided by: A) Liquid flowing down from the tray above B) Condensation of the vapor coming from the tray below C) Reflux D) None of the above

In the distillation tower, the lighter components move downwards. A) True B) False

Sub-Chapter 03: Trays An example of a tray type is: A) Bubble Point Tray B) Bubble Liquid Tray C) Bubble Cap Tray D) Bubble Vapor Tray

The __________ enters the top of the tray and leaves through the bottom of the tray in a distillation tower. A) Vapor B) Liquid

Sub-Chapter 04: Reboiler/Condenser To generate vapor at each tray, heat must be added to the tower. This heat is supplied by the: A) Reboiler C) Pumps B) Condenser D) Reflux drum

In order to maintain adequate amount of liquid within the tower, the vapor leaving the tower is cooled, condensed and returned to the tower. This cooling is achieved by supplying coolant to the: A) Condenser B) Distillation tower C) Reboiler D) Reflux drum

The light product is collected from: A) The tower bottom B) Near the feed tray C) The reflux drum D) None of the above

The reflux is: A) Condensed vapor at the top of the tower that is re-circulated back to the tower B) Liquid feed that is added to the top of the tower C) Liquid at the tower bottom that is re-circulated back to the tower

Sub-Chapter 05: Reflux Drum At the top of the tower, the vapor is cooled and condensed in a condenser, and then collected in the reflux drum. Some of this liquid is re-circulated back to the tower for cooling purposes. This re-circulated liquid is called: A) Feed B) Top product C) Reflux D) Bottom product

An increase in reflux flow to the distillation tower has no effect on the energy consumption. A) True B) False

In some distillation towers, the reboiler is replaced by sending __________ to the tower. This __________ the partial pressure of the boiling components. A) Air / Increases B) Steam / Decreases C) Steam / Increases D) Air / Decreases

Which of the following statements is true? A) Increase in partial pressure of boiling components lowers the mixture boiling point. B) Decrease in partial pressure of boiling components lowers the mixture boiling point. C) Change in partial pressure of boiling components does not affect the mixture boiling point.

Chapter 02: Basic Principles Sub-Chapter 01: Ideal Gas Law Consider a sealed container with a gas in it. When the container is heated, the pressure: A) Increases B) Decreases C) Does not change D) None of the above

Consider a sealed container with a gas in it. When the container is expanded, the pressure: A) Increases B) Decreases C) Does not change D) None of the above

The gas behavior can be approximated by an ideal gas law, PV = nRT, where P: Pressure, V: Volume, n: Number of moles, R: Gas Constant and T: Absolute Temperature. Suppose there are two sealed containers, A and B, each with identical volumes and at the same temperature, but containing 30 and 10 moles of nitrogen, respectively. What is the pressure of nitrogen in container A when compared with that in container B? A) Same B) Two times C) Half D) Three times E) Ten times

The gas behavior can be approximated by an ideal gas law, PV = nRT, where P: Pressure, V: Volume, n: Number of moles, R: Gas Constant and T: Absolute Temperature. Suppose there are two sealed containers, A and B, each with identical volumes and at the same temperature, but containing 10 and 20 moles of nitrogen, respectively. Suppose the container A is heated until its absolute temperature becomes twice as high as that of B. What is the pressure of nitrogen in container A when compared with that in container B? A) Same B) Two times C) Half D) Three times E) Ten times

Sub-Chapter 02: Vapor Pressure Consider a sealed container with pentane in liquid and vapor form, at certain temperature. When the liquid vaporization rate equals vapor condensation rate, the vapor and liquid are said to be: A) Superheated B) In equilibrium C) Subcooled D) None of the above

Consider a sealed container with pure component at equilibrium condition. The pressure exerted by the vapor is called: A) Partial pressure B) Atmospheric pressure C) Vapor pressure D) Critical pressure

The vapor pressure of a pure component can be determined by its temperature alone. A) True B) False

Sub-Chapter 03: Boiling Point If the vapor pressure of a component is higher in a gas mixture, then the boiling point of that component is also higher. A) True B) False

The water boils at approximately 100 deg C ( 212 deg F ) at sea level. The same water boils at a much lower temperature at the top of a mountain due to: A) Higher vapor pressure of water at higher altitude B) Lower atmospheric pressure at higher altitude C) The fact that the thermometer tends to indicate a lower temperature at a higher altitude

The boiling point of water and pentane at atmospheric pressure are 100 deg C ( 212 deg F ) and 36 deg C ( 97 deg F ) respectively. Which component has a higher vapor pressure? A) Pentane B) Water C) Cannot say from the above statement D) Both have the same vapor pressure

Butane boils at – 0.5 deg C ( 31.1 deg F ) at atmospheric pressure. What is the vapor pressure of butane at 10 deg C ( 50 deg F )? A) Higher than atmospheric pressure B) Lower than atmospheric pressure C) Cannot say from the above statement

Shell or Tube: Focus on Heat Exchangers In a shell-and-tube heat exchanger, is the following fluid better suited for shellside or tubeside flow? 1) Fluids that must be kept at a high velocity A) Shellside B) Tubeside

2) Process vapors that are to be condensed A) Shellside B) Tubeside

3) Corrosive fluids A) Shellside B) Tubeside

4) Fluids at extreme pressures and temperatures A) Shellside B) Tubeside

5) Very viscous fluids A) Shellside B) Tubeside

6) Streams that are likely to cause fouling A) Shellside B) Tubeside

7) Cooling water A) Shellside B) Tubeside

8) Fluid which undergoes a large temperature change or where thermal expansion is an issue A) Shellside B) Tubeside

9) Condensing steam A) Shellside B) Tubeside

IQ questions You are my son, but I'm not your father. Who says that ? The mother.

Divide 30 by 1/2 and add ten. What do you get ? 70. Dividing by half is the same as multiplying by 2.

A farmer has 17 sheep, all but 9 die. How many are left ? 9 live sheep.

A man builds a house with four sides of rectangular construction, each a southern exposure. A big bear comes along. What color is the bear ? White. If all walls face south, the house must be on the North Pole.

A women gives a beggar 50 cents; the women is the beggar's sister, but the beggar is not the woman's brother. How come ? The beggar is the woman's sister.

Is it legal for a man in Russia to marry his widow's sister ? No, he can't, he's dead.

Take 2 apples from 3 apples. What do you have ? 2 apples.

Some months have 30 days, some months have 31 days. How many have 28 ? All 12 months. Every month has at least 28 days.

Why can't a man living in the USA be buried in Canada ? Because he's not dead yet.

If you had only one match and entered a cold and dark room, where there was an oil burner, a kerosene lamp and a candle, which would you light first ? The match. Library is to book as book is to? Page

You are given a mass of 40 kg you have to divide this mass into 4 parts so that you could weigh 1 to 40kg at a time ((integer mass only) What are the weight of these pieces ? It is normal to take the first weight equal to 1 kg. So we can measure up to 1 kg. Now the logic thing would be to take the second weight equal to 2 kg. But we can skip the 2 kg and take the second weight equal to 3 kg, because by puting the first weight (=1 kg) on the other side of the balance, we can measure 2 kg. By puting the first and the second weight together, we can measure up to 4 kg as well Now the logic thing would be to take the third weight equal to 5 kg. But we can skip the 5 kg and take the third weight equal to 9 kg, because by puting the first weight and second weight together (=4 kg) on the other side of the balance, we can measure 5 kg. By puting the first and the second and the third weight together, we can measure up to 13 kg as well. Using the same logic, the fourth weight must be equal to 27 kg. In case we had only a two weight box, the weights should be 10 ad 30 kg, and we could measure 10, 20 (=30-10), 30 and 40 kg. thanks for the explanation... i happened to find another answer to this question. i divide the 40kg weight into 4 parts of weights 2,6,7,25kgs respectively. I'll be able to make numbers from 1 to 40 using these 4 numbers using + and operations 7-6 =1 7+2-6 =3 6-2 =4 7-2 =5 6+2 =8 7+2 =9 25-7-6-2 =10 7+6-2 =11 25-7-6 =12 7+6 =13 25-7-6+2 =14 7+6+2 =15 25-7-2 =16 25-6-2 =17 25-7 =18 25-6 =19 25+2-7 =20 since i have proved it to be working for 1 to 20 it will also work for 21 to 40.

You are driving along in your car on a wild, stormy night, it's raining heavily, When suddenly you pass by a bus stop, and you see three people waiting for a bus: 1. An old lady who looks as if she is about to die. 2. An old friend who once saved your life. 3. The perfect partner you have been dreaming about. Which one would you choose to offer a ride to, knowing very well that there could only be one passenger in your car? Get out of the car, ask the old friend to drive the old lady to a hospital and then drive himself home. I'll stay at the bus stop with my dream partner.

At the end of a banquet 10 people shake hands with each other. How many handshakes will there be in total? One person starts shaking the other 9 people's hands. He has now shaken everyone's hand once and doesn't need to shake again. The next person shakes the remaining 8 people's hands once each and then he/she is done. The next person shakes the remaining 7 people's hands, and so on until the last two people shake hands. 9+8+7+6+5+4+3+2+1=45 shakes

What day is today if the day before the day before yesterday is three days after Saturday? The best way to work these out is to go backwards. Start with Saturday. 3 days after Saturday is Tuesday. Then the beginning part is three days: yesterday, the day before, and then the day before that. So today is Friday. Then read through it and plug your answer in. Okay, so yesterday was Thursday, and then two days before that us Tuesday, which is 3 days after Sunday. Another way to solve this is guess and check.

165135 is to peace as 1215225 is to? A is the 1st letter of the alphabet, thus it is 1, and so on. P=16 E=5 A=1 C=3 E=5 Thus Peace = 165135. L=12 O=15 V=22 E=5 Thus Love = 1215225

If a pipe takes 8hours to fill a tank And another pipe takes 4 hours to empty the tank. When both of the pipes are on. how much time will it take to fill the tank? The rates are additive when both pipes are fully open at the same time. Filling pipe, (1/8) tank per hour Emptying pipe, (-1/4) tank per hour Combined Rate,(1/8 – 1/4) tank per hour. Notice very carefully that rate of filling is smaller than the rate of emptying. YOU CANNOT FILL THIS TANK WHEN BOTH PIPES ARE OPEN!! Simplify to (1/8 – 2/8 = -1/8) tank/hour. This tank will never fill when both pipes are open all the way.

It takes 3 workers 1 hour to pack 6 boxes. At that rate, how long will it take 9 workers to pack 36 boxes? Since it takes 3 workers 1 hour to pack 6 boxes, it would take those 3 workers 6 times as long to pack 36 boxes, or 6 hours. But 3 times as many workers (9 workers) could pack them in one-third the time, or 2 hours. Or you can use the worker-time-job formula, which is:

= where W1 = the number of workers in the first situation. T1 = the number of time units (hours in this case) in the first situation. J1 = the number of jobs (boxes filled) in the first situation.

W2 = the number of workers in the second situation. T2 = the number of time units (hours in this case) in the second situation. J2 = the number of jobs (boxes filled) in the second situation. W1 = 3 T1 = 1 J1 = 6

W2 = 9 T2 = the unknown quantity J2 = 36 =

= (3/6) reduces to (1/2) and (9/36) reduces to (1/4)

= Cross-multiply 2T2 = 4 Divide both sides by 2 T2 = 2 Answer: 2 hours

Ball Valve

Diaphragm valve

Plug valve

Cryogenic Globe Valve

Pinch valve

Safety valve

take a break

LIST OF QUESTIONS which is best field to work for chemical enggTop of Form suggest me text books of fluid flow. I neeeed explain in electrochemical and corrosion I want to learn specific heat capacitiy of calcium succinate and acetate for different temperature. i need in details how to design heat exchanger How can i download videos ?? What is the diferent LDPE AND HDPE ? Why is LMTD used ? why saturated steam used in reboilers not superheated steam ??? why do we use horizontal or vertical centrifugal pumps what is ment hydrophilic hydrophobi liophobic bonds can u explain gibbs-duhem equation? Aquoeus solution can you say difference between inflammable and flammable

LIST OF QUESTIONS viscosity is more in gases are liquids which bomb is more powerfull hydrogen or atom bomb what's meant by homogeneous isotropic solids which type of packing used in cryogenic distillation column & why? is there any techniq to seprate co2 from gases what is difference between shear stress, pressure nd thrust. what is difference between radial and axel flow pumps guys can u expliain me why the suction pressure should be more than vapour pressure in order to avoid the cavitation in the centrifugal pumps? Why Sulphuric Acid is Colourless?? what is the crtical temperature 1 mg NaCl/liter of distilled water = 1 ppm TDS Am I right or can't this be used? can u define the difference between mesh size & micron size. plz tell,, me how to manufacture phthalic anhydride in industry & require equipment for production of phthalic anhydride. What are Azeotropes?

LIST OF QUESTIONS IS THERE ANY RELATION SHIP BETWEEN DEW POINT AND PRESSURE what is purging?? Can u explaine uses of ester what is the relation between velocity and pressure...... if they both are directly proportional.......what do you say about venture meter where velocity increses when pressure decreases? where can I get the complete information about INSTRUMENTATION AND PROCESS CONTROL Mai i know what is the reason for having 2different system for pressure units i.e, kg/cm squ. why vacuum pressure created in gas condensate distillation plant (re boiler & column) plz let me know the clear meaning of heat capacity & specific heat CAN U EXPLIN ME THE DIFFERENCE BETWEEN specific heat and heat capacity how the air filled in a cycle tube was not coming out? which software should i use to draw process flow diagrams ? wts ment by leadent heat of frost point

LIST OF QUESTIONS can you please say physical and chemical properties of ethanol why cavitation is not happening in reciprocating pump......?if it is because of some extra devise why cant we make centrifugal pump...like that? Any good suggestion for my thesis? The topic should be related to petroleum refining because i am a scholar of a certain petroleum refining company. thank you Can you please say what are the safety precautions to be taken for preparation of ethyl alcohol from molasses fermentation i need picture of High Temperature and low temperature shift converter in ammonia plant, can you send me this picture please. how can I make design for Reactor (PFR) using polymath program? what is hagen and poiseuille laws? 1micron=-----???------m can i get the photos of valves what is the difference between heat and temperature who khow about "chem e car"'s system? What is the significance of the nitrogen system in the plant?

LIST OF QUESTIONS Does any one can explain the difference between Liquid-Liquid Extraction and distillation process in the separation of liquid mixture? Does anyone know where I can find the roughness of BWG tubes? Write the name of chemical which is used for natural gas drying operation? what is difference between pressure and pressure energy . and also explain relation between pressure and area , pressure energy and area Gve me some seminar topcs. how the problem of flooding in a distillation column is confronted in an industry? What is the diffrence between vapour & steam Difference between vacuum and pressure why does the sphere gives more surface area and volume than any other shaped object how to creat a place of artificial gravity? what r the different things to be considered.. CAN U EXPLAIN ABOUT SOLID LIQUID EXTRACTION AND LIQUID LIQUID EXTRACTION? What is the vacuum distillation?

LIST OF QUESTIONS what is E and Z nomanclature in organic chemistry Why combustion is not an reversable reaction can anyone explain difference between upstream and downstream process in oil and gas industry? what is the main difference bet absorption and adsorption sep process??? wt is the difference between heat and temperature. can we use nitrogen for stripping in a crude column,if so how and not why i want to download aspen plus for windows 8 or chemcad can u help me with a torrent link or some other way to download it pls reply asap!!!! Can someone please differenciate between absorption and adsorption in terms of mass transfer CAN ANY ONE OF TELL WHAT ARE THE CHARACTERISTICI OF IDEAL LIQUID ? what is surging in compressor? How jet mill works and describe its industrial uses? what type of radiation is primarily responsible for the production of ions in ionosphere?

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LIST OF QUESTIONS Why PFR is better than CSTR...? & why conversion in PFR is more compare than CSTR...? in crystallization process......solubility increses with increse in temp...bt for mnso4 solubility is decresing with temp....can you tell me why? how can we soften the lattice adhesion below the carpet what is the difference between unbound moisture content and free moisture content? what you have to do if the solvent is more volatile in crystallization operation? what you have to do when the solution is more viscous and forms a layer at the bottom of crystallizer?

I am a student Of Chemical Engineering, studing in Thadomal Shahani Engineering College. I Am currently in my final year of BE. I am doing a Project on "Design OF Sulphur Condenser". Now i am stuck on a calculation. I thought U guys can help me. i just wanted to know the antoine constant of sulphur i.e. A B C . i have found of hydrogen sulphide and sulphurdioxide but i am stuck at this. It would be of great help if u people can do anything about it

can you say what are the olechemicals obtained from Sesame oil What is the methods of Natural Gas Liquefaction?

LIST OF QUESTIONS .in distillation where we need to use partial condenser and where to use final condenser......and what is the main difference we observe when using these two can u xplin me about thermodynamic steam trap....what is the purpose of strainer thr? what is the difference btwn foot valve and non return valve? what is the difference btwn HETP and HTU? WHAT IS THE DIFFERENCE BETWWEN IMPELLER AND PROPELLER? cant we make self priming centrifugal pump....if so why? is surge occurs only in centrifugal compressors????if sooo what abt the rest...why it is nt happening to them Which distillation is stubble for higher viscous fluids? Help in providing Isocyanide prepartion technology ??????? tell me Which book should I refer for gas absorption with chemical reaction? what is ment by monatomic molecules what is the importance of specific gravity what are the basic properties of crayogenic fluids

LIST OF QUESTIONS What is TEAL? Any idea? what do u mean by a solvate? and where will they form What is Hot Tapping mean? what are the diff betn shell-tube H.E and double pipe H.E? what is the major diffrence between "azeotropic" and "extractive distillation".? difference between kerosine and gasoline...? difference between cracking and pyrolosis? i need more xplanation abt differences btwn extractive and azeotropic distillation What is difference between fouling and scaling? i wanna some information about cooper silver ionisation as a disinfection method İ will begin in a aerosol can factory as a chemical engineer. Do you have some information about aerosols and aluminium can Is there any material related to paint technology..? "what is - & + feedback?"

LIST OF QUESTIONS i have try to found the activation energy and reaction constant for thet wo reaction below but i cant found any result , plz if u can help me CH4+H2O→CO+3H2 CO+H2O→CO2+H2 Could you please describe the difference of polytropic and isentropic efficiencies of gas compressor? Thank you very much in advance. r u plz snd me shorts notes 4 axial n radial flow impeller Why should people interested in chemical Engineering field? Please Describe me Explain the process of extraction of petrol with flow chart. .a black body at 3000k emits radiation,calculate the maximum emissive power & t0tal emissive power. i wanna attempt to construct a viable home based ammonia or urea production unit. using methane or LPG. In your opinion, is this possible to do profitably? And if it is cud u send me links to some literature tht myt help me out. what is the check point of pump starting? can you please inform me the difference between partial condensor and total condensor used in distillation column why some pumps circulation is to the vessel and others from disharge to suction and others no circulations?

LIST OF QUESTIONS My Question is this "Heart is what type of Blood pump??" Esterification reaction is endothermic or exothermic? plz tell me... the scope for chemical engineering Disadvantage of solral energy ? plz give me sample example on technical report writing and the full format Can any one pls give of the difference between leaching and extraction. Pls give atleast 5 difference. Is it neccessary to calculate NPSH for centerfugal pump.Tell about its significance. I want to all valves video so please show me the details where is download if maybe you could provide me with some information on the terephthalic acid production process. In particular, the Invista technology. i want to know what's pilot plant and also model plant? What's the difference between pilot plant and model plant? May you please help me finding Valves and pumps API ?? Which is humidity ? If there is 44%humidity what it means ? And What is unit process ?

LIST OF QUESTIONS what r the differnce between adsorption and absorption ? pls write (post) about Alkyd Resin. wet & dry bulb temperature ? If i am using vaccuum distillation..what wl be its purpose? can you give me informations about PROCESS OF OFFSET NEGATIVE My professor assigned me a report regarding Cr(III). Can you help me? will they have any information on distillation automation? and also isomerization of paraffins 5 and 6 carbon atoms and which improve the anti-knock? any mechanical design Multibed adiabatic fixed-bed reactor with interstage heat exchange and collector designe of distillation coulmn>>diameter>>Height>>>Thickness of the cylindrical section>>> Can a plate heat exchanger do the task of multiple shell and tube heat exchangers? i need more info about production of sulphonic acid using conc sulforic acid Difference betn fan,blower,compressor

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LIST OF QUESTIONS what is the difference between phase equilibrium and temperature equilibrum? I wish study Azeotropic distilation you explain with me What is the difference between sodium nitrate&sodium nitrite?.sodium nitrate is a strong passivation agent? which one is strongest passivation agent?why a)sodium nitrate b)sodium nitrite c)hydrazine hydrate d)hydrogen peroxide does modes of heat transfer(conduction and covection) affected by gravity? can be store compressed air in confined space i am searching about semicoductors, what is chemical amplification resist? and what is the limitation of this technology? why shorter wavelengths is required for the production? what is the problem that lead the researchers to invent chemical amplification? Why reflux is require in distillation?What is it's advantage? Can explain the relation between wet bulb temp, dry bulb temp, dewpoint, and humidity, effect one on another ?

LIST OF QUESTIONS What is the difference between free energy and gibbs free energy. why we add steam into the coloumn before to start distillation process? do i have any chance that you mention the process of production of hexamehylenediamine? . im writing this message to ask u about the nitrogen that is commun used in plant. Please can u give me data about how is used in storages and in purge and for example when the product is solid and need to be exit from the process how the nitrogen is used as an inert environment int hat case.

which is best field to work for chemical enggTop of Form i think any field has a reactor is better, because you will study about catalysis and kinetics, you will find reactor at more fields for example petrochemical and fertilizers. on the other hand, if you worked at oil or gas fields, you will have experiences in a distillation towers and its trays.

al of chemical engineering fields have a special pleasure but the most important thing to work as an engineer not employee, i mean to be creative. good luck eng. I neeeed explain in electrochemical and corrosion check this torrent there is a folder called " Electrochemistry" contains 6 references about that. http://www.mediafire.com/?8dtm65i5ya9w6cr

Admin : Tally i need in details how to design heat exchanger this reference is very helpful for you http://www.mediafire.com/?ok458fnc4b5ky3h and if you want software, the best software are 1- aspen exchanger design and rating 2- sime sin

ah.yehia http://people.clarkson.edu/projects/subramanian/ch302/notes/designshelltube.pdf Admin : Tally why saturated steam used in reboilers not superheated steam ??? saturated steam when inlet (vapor phase) .. water outlet (liquid phase) and that can be pumped using pump but superheated steam inlet (vapor phase) .. saturated steam outlet (vapor phase) and this phase cannot be pumped using pump ah.yehia suggest me text books of fluid flow. "Chemical engineering fluid mechanics" by Ron Darby

why do we use horizontal or vertical centrifugal pumps You may want to conserve floor space, A horizontal pump has a larger floor space foot print than a vertical pump. Orientation also plays a part in servicing the pump. Larger pumps may need to be serviced in place by removing the casing and lifting therotor out. Overhead clearance and orientation can aid or hinder servicing.

Small Vertical pumps are less sensitive to misalignment caused by setteling of the foundation(floor) mount. Large pumps can benefit from horizontal orientation in the relative ease to perform coupling alignment between the pump and motor shafts. Shims are placed between the motor feet and foundation plate, and mounting bolts are passed through elongated holes. Horizontal mounting allows easier relocation of the motor as necessary while a vertical mount is limited by the mounting frame to which the motor attaches. EDIT: Once done at the factory the vertical pump motor is easier to replace as the motor mount takes care of most of teh alignment Vertical pump orientation also allows the pump to be placed at a lower level to assist in minimizing suction lift (Or provide a flooded suction). The pump could be located under the deck plate level in the bilge while the electric motor is above the deck plate high and dry. (Deep well pumps used in lift stations take this to the extream by using shafts several feet or more of shaft to maximize pump and motor seperation to provide a flooded suction) Pump orientation also effects bearing loading for not just the radial bearings but the thrust bearings as well. So bearing design is effected, this isn't a big deal for the user but is a consideration in the design of the pump. Pump orientation can also assist in pipping design. Wether or not a pipe can enter a pump suction from the axial vs radial direction and at what elevation can be a factor in pump selsction http://answers.yahoo.com/question/index?qid=20080925150249AAfa1TP -------------------------------------------------------------------1. The horizontal is a better accepted standard because of tradition, cost, & availability; 2. There is no perceptible difference in NPSH requirements between both versions; they can both handle equal NPSH situations – if properly selected and installed; 3. Vertical pump orientation demands overhead space for maintenance – especially in the heavier horsepowers, such as 15+ hp; for larger motors you require an overhead rail and hoist. Horizontals are easier to manhandle and lift, shift around.

why do we use horizontal or vertical centrifugal pumps 4. Once you commit to a vertical, you have for all practical purposes increased your investment and inventory in spare parts. Vertical design is very specific as to type of bearings – primarily thrust – and these cause you to have to duplicate inventory for your vertical pumps. You can no longer have the benefit of exchanging motors and couplings with the ease you experience when you standardize on horizontals only. 5. Some vertical designs are really “tight” for space in the coupling distance piece area (in order to reduce overall height and turning moment) and this makes it rough for maintenance and handling seal leakage and maintenance. This used to be a big problem with horizontals as well, until ANSI and API specs were applied. 6. Verticals require special piping design in order to alleviate or eliminate all piping loads due to pump weight – especially in the smaller sizes; 7. Eventually, in some cases, you wind up having to independently supporting the vertical pump with structural steel – a fact that starts to defeat one of the original unique features of having a vertical pump in the first place. I have found that basically ALL pumps should have their own independent support (or foundation) in order to remove and piping stresses and allow the pump to operate with ease and totally independent. http://www.cheresources.com/invision/topic/4290-horizontal-vs-vertical-centrifugalpump/ ah.yehia What is the diferent LDPE AND HDPE ? LDPE and HDPE have different properties, The main difference is is that LDPE is softer, more flexible and melts at a lower temperature than HDPE. So it used for things such as plastic sandwich bags. Whereas HDPE is much harder and is used for plastic bins etc ah.yehia Why is LMTD used ? Because the temperature change that occurs across the heat exchanger from the entrance to the exit is not linear, and a logarithmic function best describes this temperature change. ah.yehia I want to learn specific heat capacitiy of calcium succinate and acetate for different temperature. you can try searching in Kern...Magnificent reference in heat transfer.

what is ment hydrophilic hydrophobi liophobic bonds "Lyophobic" is a descriptive term for the state of some matter particles when combined in a solution. The term comes from the breakdown of lyo, meaning "solvents," and phobic, meaning "hating." Lyophobic materials hate all solvents, unlike hydrophobic materials that only hate water. Solvent-hating materials such as iron, mercury, arsenic, and precious metals such as gold and platinum require special handling. These materials usually combine in solutions called colloidal solutions; lyophobic colloids are one of the two main types of colloidal solutions. As solvent-hating materials do not readily form solutions, various elaborate preparations are made to present them in a useful compound. The properties of lyophobic materials include their irreversibility and their instability. They are considered irreversible organic compounds because, if the solvent is removed, they do not easily form another compound by mere introduction of solvent once again. Lyophilic colloid materials, which are considered solvent-loving, are considered reversible as they readily recombine. The lyophobic materials in solution are considered less stable, because their forces of interaction with other materials are so weak compared to the strong bonds of lyophilic materials. Their molecules repel other materials, thus must be manipulated to make it possible to create colloidal solutions. One of the properties of lyophobic colloidal solutions that differentiate them from lyophilic colloidal solutions is their behavior under positive and negative electrical charges. Lyophobic solutions under an electrical field will immediately move to the negative if a negative charge is applied and to the positive if a positive charge is applied. Lyophilic solutions do not respond to electrical charges at all, unless the dispersing agent they were dissolved in responds to the charge — in which case, they follow their dispersant. The lyophobic solutions of starches, proteins, and sulphurs have a similar or equal viscosity as their dispersal solvents, whereas lyophilic solutions are far more tacky than their dispersal solvent. As the liquid-hating substances require manipulations and stabilizers to achieve compound solutions, several preparations have been developed according to the essential nature of the particular lyophobic material. For instance, to achieve a colloidal compound with gold, reducing agents like formaldehyde or hydrogen peroxide can be used to treat gold's salts to produce a gold solution that has a purple tint. Mercury is prepared by changing its physical state when its vapors are passed through a cold-water bath with a stabilizer such as ammonium salt added. Varnishes, paints, and black inks are lyophobic colloidal materials that pass through a mechanical colloidal mill that grinds the solution between two rotating discs to create a shearing force to combine them when the particles are at nanometer size. ah.yehia

what is ment hydrophilic hydrophobi liophobic bonds Hydrophobic Molecules Don’t Make Hydrogen Bonds with Water In contrast, fats that float and don’t dissolve in water are called hydrophobic, but that doesn’t mean that fats hate water or are pushed away from water, it simply means that fats can’t form hydrogen bonds with water. Since bonding means that energy is released as molecules come into contact, then water molecules forming hydrogen bonds are in a lower energy state than water molecules in contact with a hydrophobic molecule, such as a fat. Random movement of a mixture of fat and water will eventually result in the water molecules sharing the minimal possible surface with the fat, because that is the lowest energy configuration. Typical hydrophobic molecules include: fats, steroids, lipids, aromatic compounds (such as some drugs) ah.yehia Hydrophilic Molecules Make Hydrogen Bonds with Water Molecules that dissolve or interact with water, such as carbohydrates, are said to be hydrophilic, water loving, but these molecules just dissolve in water, because they form H-bonds with water molecules. Each hydroxyl (-OH) group on a carbohydrate can make hydrogen bonds to three different water molecules. The hydrogen can bond to a pair of valence electron on the oxygen of water and each of the two pairs of valence electrons of the hydroxyl can bond to a hydrogen of water. Most of the molecules within cells can form H-bonds and are hydrophilic. Typical hydrophilic molecules include: proteins, carbohydrates, nucleic acids (DNA and RNA), salts (form ionic bonds), small molecules of metabolism (e.g. glucose, amino acids, ATP) ah.yehia can u explain gibbs-duhem equation? http://www.thermopedia.com/content/815/ http://en.wikipedia.org/wiki/Gibbs%E2%80%93Duhem_equation

which type of packing used in cryogenic distillation column & why? Cryogenic separation unit are operated at extremely low temperature and high pressure to separate components according to their different boiling temperatures Cryogenic separation is widely used commercially for purification of CO2 from streams that already have high CO2 concentration. Need for relatively high concentration of CO2 for cryogenic unit is important because in order to minimize CO2 loss from the top of the column it would be necessary to operate as close to the triple-point temperature as possible, but the minimum partial pressure of CO2 achievable in the vent gas would be 5.18 bar abs. this meant that as the concentration of other component in the CO2/gas mixture increases the pressure of the stripping column would have to be increased in order to achieve a certain CO2 recovery from process. At 75% feed purity and 90% recovery, the column pressure would be about 26 bar pressure, for 95% recovery it would be 46 bar. https://www.facebook.com/photo.php?fbid=556619167717845&set=a.4798264320637 86.109797.479381242108305&type=1&theater B.H which bomb is more powerfull hydrogen or atom bomb Hydrogen bomb Hydrogen bomb = fusion. Atomic bomb = fission. Fusion bombs have a much bigger effect. Atomic bombs are actually at the center of fusion bombs---they are what fires them off. ah.yehia viscosity is more in gases are liquids sure liquid is more viscosity http://hyperphysics.phy-astr.gsu.edu/hbase/tables/viscosity.html This is because in gases, the molecules are further apart and there's more space between the molecules so they can be compressed more than liquids. Also the intermolecular forces of attraction between gas molecules is weaker compared to liquids hence they also have lower viscosities. ah.yehia What is the difference between sodium nitrate&sodium nitrite?.sodium nitrate is a strong passivation agent? sodium nitrate is NaNO3 and sodium nitrite is NaNO2. NaNO3 is an oxidizing agent and converts to NaNO2 on reduction by heat. Shantanu Lanke

can you say difference between inflammable and flammable Both words mean the same thing, i.e. that something can be set on fire. The reason for the confusion comes from people thinking that the prefix in- of inflammable is the Latin negative prefix in- (which is commonly used in English, e.g. indecent). In actual fact, in this case it is derived from the Latin preposition in. It's easier to think about it with the word inflame. If you can inflame something, it is inflammable (inflame-able). In most cases, it is better to just use flammable to avoid confusion and accidents. ah.yehia what's meant by homogeneous isotropic solids Alloys are homogeneous mixture of at least two metals: bronze (Cu, Sn) and brass (Cu, Zn) are example of two copper alloys. ah.yehia Aquoeus solution http://en.wikipedia.org/wiki/Aqueous_solution Definition: An aqueous solution is any solution in which water (H2O) is the solvent. Examples: cola, saltwater, rain How can i download videos ?? copy video link and go to this website http://keepvid. com/ past video link and press download ah.yehia guys can u expliain me why the suction pressure should be more than vapour pressure in order to avoid the cavitation in the centrifugal pumps? cavitation basically occurs due to decease in boiling point due to reduction in pressure. if u reduce the pressure below its vapor pressure at RT, waterwill boil below RT and cavitation will occur. Shantanu Lanke Why Sulphuric Acid is Colourless?? it does not contain any species (groups of atoms, or specific types of bonds) that strongly absorb wavelengths in the visible spectrum when light is incident upon it. ah.yehia

is there any techniq to seprate co2 from gases Brief on Ammonia production from Natural Gas 1) Feed-stock desulphurization This part of the process is to remove the sulfur from the feed-stock over a Zinc oxide catalyst bed, as sulfur is poison to the catalysts used in the Subsequent processed. The sculpture level is reduced to less than 0.1 ppm in this part of the process. 2) Primary Reforming The gas from the desulphuriser is mixed with process steam, usually coming from an extraction turbine, and steam gas mixture is then heated further to 500-600 °C in the convection section before entering the primary reformer. Sometimes in some plants the preheated steam/gas mixture is passed through an adiabatic pre-reformer and reheated in the convection section before entering the primary reformer.

The amount of process steam is given to adjust steam to carbon-molar ratio (S/C- ratio), which should be around 3.0 for the reforming processes. The optimum ratio depends on several factors, such as feed-stock quality, purge gas recovery, primary reformer capacity, shift operation and the plant steam balance. In new plants, S/C ratio may be less than 3.0. The primary reformer consists of a large number of high-nickel chromium alloy tubes filled with nickel-containing reforming catalyst in a big chamber (Radiant box) with burners to provide heat. The overall reaction is highly endothermic and additional heat is provided by burning of gas in burners provided for the purpose, to raise the temperature to 780-830 °C at the reformer outlet. The composition of gas leaving the reformer is given by close approach to the following chemical equilibrium: CH4 + H2O = CO + 3H2 CO + H2O = CO2 + H2 The heat for the primary reforming is supplied by burning natural gas or other gaseous fuels, in the burners of a radiant box containing catalyst filled tubes. The flue gas leaving the radiant box has temperature in excess of 900 °C, after supplying the high level heat to the reforming process. About 50-60% of fuel’s heat value is directly used in the process itself. The heat content (waste heat) of the flue-gas is recovered in the reformer convection section, for various process and steam duties. The fuel energy required in the conventional reforming process is 40-50% of the process feed energy. The flue-gas leaving the convection section at 100-200 °C is one of the main sources of emissions from the plant. These emissions are mainly CO2, NOx, with small amounts of SO2 and CO.

is there any techniq to seprate co2 from gases 3) Secondary reforming Only 30-40% of the hydrocarbon feed is reformed in the primary reformer because of the chemical equilibrium at the actual operating conditions. The temperature must be raised to increase the conversion. This is done in the secondary reformer by internal combustion of part of the gas with process air, which also provides the nitrogen for the final synthesis gas. In the conventional reforming process the degree of primary reforming is adjusted so that the air supplied to the secondary reformer meets both the heat and the stoichiometric synthesis gas requirement. The process air is compressed to the reforming pressure and heated further in the primary reformer convection section to about 600 °C. The process gas is mixed with the air in a burner and then passed over a nickel-containing secondary reformer catalyst. The reformer outlet temperature is around 1000 °C, and up to 99% of the hydrocarbon feed (to primary reformer) is converted, giving a residual methane content of 0.2-0.3 (dry gas bases) in the process gas leaving the secondary reformer. The process gas is cooled to 350-400 °C in a waste heat boiler or waste heat boiler/super heater down stream from the secondary reformer. 4) Shift conversion (High & Low) The process gas from the secondary reformer contains 12-15% CO (dry gas bases) and most of the CO is converted in the shift section according to the reaction: CO + H2O = CO2+ H2 In the high temperature shift conversion (HTS), the gas is passed through a bed of iron oxide/Chromium oxide catalyst at around 400 °C, where the CO content is reduced to about 3% (dry gas bases), limited by the shift equilibrium at the actual operating temperature. There is tendency to use copper containing catalyst to increase conversion. The gas from the HTS is cooled and passed through the low temperature shift (LTS) converter. The LTS is filled with a copper oxide/Zinc oxide-based catalyst and operates at about 200220 °C. The residual CO content is important for the efficiency of the process. Therefore, efficiency of shift step in obtaining the highest shift conversion is very important. 5) CO2 Removal The process gas from the low temperature shift converter contains mainly H2, N2, CO2, and excess process steam. The gas is cooled and most of the excess steam is condensed before it enters the CO2 removal section. This condensate usually contains 1500-2000 ppm of ammonia, 800-1200 ppm of methanol and minor concentration of other chemicals. All these are stripped and in the best practices the condensate is recycled. The heat released during cooling/condensation is used for: regeneration of CO2, scrubbing solution.

is there any techniq to seprate co2 from gases The amount of heat released depends on the process steam to carbon ratio. If all this low level heat is used for CO2 removal or absorption refrigeration, high-level heat has can be used for feed water system. An energy-efficient process should therefore have a CO2 removal system with low heat demand. The CO2 is removed in a chemical or physical absorption process. The solvents used in chemical absorption process are mainly aqueous amine solutions Mono Ethanolamine (MEA), activated Methyl DiEthanolamines (aMDEA) or hot potassium carbonate solutions. Residual CO2 content are usually in the range 100-1000 ppmv, depending on the process used. Contents of CO2 down to 50 ppmv are achievable. 6) Methanation (not in all plants) The small residual amount of CO and CO2 in the synthesis gas, are poisonous for the ammonia synthesis catalyst and must be removed by conversion to CH4 in the methanator : CO + 3H2 = CH4 + H2O CO2 + 4H2 = CH4 + 2H2O The reaction takes place at around 300 °C in a reactor filled with nickel containing catalyst. Methane is an inert gas but water must be removed before entering converter. 7) Synthesis Gas Compression and Ammonia Synthesis Modern ammonia plants use centrifugal compressors for synthesis gas compression, usually driven by steam turbines, with steam being produced within the ammonia plant from exothermic heat of reactions. The refrigeration compressor, needed for condensation of product ammonia, is also driven by a steam turbine. The synthesis of ammonia takes place on an iron catalyst at pressure usually in the range of 100- 250 kg/cm2 and temperatures in the range of 350-550 °C: N2 + 3H2 = 2NH3 Only 20-30% of synthesis gas is converted to ammonia per pass in multi bed catalyst filled the converter due to the unfavorable equilibrium conditions. The ammonia that is formed is separated from the product gas mixture by cooling/ condensation, and the unreacted gas is recycled with the addition of fresh make up synthesis gas, thus maintaining the loop pressure. In addition, extensive heat exchange is required due to exothermic reaction and large temperature range in the loop. Conventional reforming with methanation as the final purification step, produces a synthesis gas contains inerts (Methane and argon) in quantities that don’t dissolve in the condensed ammonia. The major part of these is removed by taking out a purge stream from the loop. The size of this purge stream controls the level of inerts in the loop to about 10-15%. The purge gas is scrubbed with water to remove ammonia before being used as fuel or before being sent to hydrogen recovery unit.

is there any techniq to seprate co2 from gases Ammonia condensation is far from complete if cooling is with water or air and is usually not satisfactory. Vaporizing ammonia is used as a refrigerant in most ammonia plants, to achieve sufficiently low ammonia concentration in the recycled gas. The ammonia vapours are liquefied by compression in the refrigeration compressor. The process described is shown in the following Block flow diagram. https://www.facebook.com/photo.php?fbid=555352814511147&set=a.4839795783151 38.110606.479381242108305&type=1&relevant_count=1 M.Salah what is difference between shear stress, pressure nd thrust. Shear = cut and thrust = push.

Hydrostatic pressure acts uniformly along all sides perpendicular to the surface and the shear stress acts only along or parallel to the surface. Stress (mechanics), the average amount of force exerted per unit area. It is the internal resistance a material offers to being deformed and is measured in terms of the applied load. The effects of mechanical stress on a polymer can be measured using dynamic mechanical analysis. Strain (mechanics) geometrical measure of deformation representing the relative displacement between particles in a material body, i.e. a measure of how much a given displacement differs locally from a rigid-body displacement. Pressure (symbol: P) is the force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure. As an example of varying pressures, a finger can be pressed against a wall without making any lasting impression; however, the same finger pushing a thumbtack can easily damage the wall. Although the force applied to the surface is the same, the thumbtack applies more pressure because the point concentrates that force into a smaller area. Pressure is transmitted to solid boundaries or across arbitrary sections of fluid normal to these boundaries or sections at every point. Unlike stress, pressure is defined as a scalar quantity. ah.yehia

what is the crtical temperature critial temperature is the temp. at whichthere are no phase boundary occur between different phases of matter. Shantanu Lanke Critical Temperature Gases can be converted to liquids by compressing the gas at a suitable temperature. 2-The temperature at which a material becomes a superconductor. Critical Pressure The critical pressure of a substance is the pressure required to liquefy a gas at its critical temperature. https://www.facebook.com/photo.php?fbid=561579673888461&set=a.4798264320637 86.109797.479381242108305&type=1&theater B.H

what is difference between radial and axel flow pumps In axial flow pumps, fluid enters and exits along the same direction parallel to the rotating shaft giving high flow rates and low head. In radial flow pumps, fluid enters and leaves perpendicular to the rotating shaft giving high head and low flow rates. Thus, in mixed we have combined of both axial and radial.i.e.Liquid will go behind the impeller at certain angle between 0-90degrees normally below 45degree.Mixed flow replace axial when we require head not provided by the axial pump as we have to lift water from a water a lower level and then discharge it. physically,mixed flow can be identified by bellmouth(diverging converging shape) which shows its between axial and radial. ah.yehia can u define the difference between mesh size & micron size. Mesh size would be the number of holes per inch and Micron size would be used to indicate the size of the holes in the mesh in microns or 1/1000000 of a meter. One micron meaning one millionth. Mesh size is usually used in the US. It's just an alternative system used to describe the hole size. For example, 35 mesh (US) is the same as 0.5mm or 500 microns. ah.yehia

What are Azeotropes? Mechanism of azeotrope formation: Azeotropes can only form when a mixture deviates from Raoult's law. Raoult's law applies when the molecules of the constituents stick to each other to the same degree as they do to themselves. For example, if the constituents are X and Y, then X sticks to Y with roughly equal energy as X does with X and Y does with Y. A positive deviation from Raoult's law results when the constituents have a disaffinity for each other – that is X sticks to X and Y to Y better than X sticks to Y. Because this results in the mixture having less total sticking together of the molecules than the pure constituents, they more readily escape from the stuck-together phase, which is to say the liquid phase, and into the vapor phase. When X sticks to Y more aggressively than X does to X and Y does to Y, the result is a negative deviation from Raoult's law. In this case because there is more sticking together of the molecules in the mixture than in the pure constituents, they are more reluctant to escape the stuck-together liquid phase. When the deviation is great enough to cause a maximum or minimum in the vapor pressure versus composition function, it is a mathematical consequence that at that point, the vapor will have the same composition as the liquid, and so an azeotrope is the result. azeotropes is a mix. of two or more liquids that cannot be separated by simple distillation. this is due to the Shantanu Lanke azeotrope is a mixture of two or more liquids in such a way that its components cannot be altered by simple distillation. liquid mixture with a constant maximum or minimum boiling point lower or higher than the boiling points of its components and with the capacity to distill without change in composition . there are two types of azeotropy:1- Positive azeotropes are also called minimum boiling mixtures or pressure maximum azeotropes. 2-Negative azeotropes are also called maximum boiling mixtures or pressure minimum azeotropes. If the constituents of a mixture are not completely miscible an azeotrope can be found inside the miscibility gap. This type of azeotrope is called heterogeneous azeotrope. If the azeotropic composition is outside the miscibility gap or the constituents of the mixture are completely miscible the type of azeotrope is called a homogeneous azeotrope. https://www.facebook.com/photo.php?fbid=563871970325898&set=a.479826432063 786.109797.479381242108305&type=1&theater B.H

1 mg NaCl/liter of distilled water = 1 ppm TDS Am I right or can't this be used? you are right X ppm TDS = X mg of salts + one liter of distilled water. Remember that "X mg of salts" is the number of milligrams of a mixture of salt of which proportions ah.yehia plz tell,, me how to manufacture phthalic anhydride in industry & require equipment for production of phthalic anhydride. ("Gibbs phthalic anhydride process"): C6H4(CH3)2 + 3 O2 → C6H4(CO)2O + 3 H2O C10H8 + 4.5 O2 → C6H4(CO)2O + 2 H2O + 2 CO2 The catalyst that is used for the oxidation of xylene is a modified vanadium pentoxide (V2O5). When separating the phthalic anhydride from byproducts such as o-xylene in water, or maleic anhydride, a series of “switch condensers” is required. Phthalic anhydride can also be prepared from phthalic acid: C8H6O4 ------>C6H4O3 + H2O Shantanu Lanke IS THERE ANY RELATION SHIP BETWEEN DEW POINT AND PRESSURE With a low pressure system you will get rain/ snow. Dew point is the relative temperature at which it will rain. Thus, a low pressure will make the dew point rise or decrease depending on the Temperature at which it needs to be in order to rain. When it comes to temperature the warmer it is the more saturated the the atmosphere is and thus if we up/down the dew point it will rain. Keep in mind the higher the dew point the higher the temperature needs to be to rain. Higher DP= higher saturation. When it comes to high pressure that deals with relatively calm/stable weather, because of the lowering of air. Thus, lower dew point. ah.yehia Can u explaine uses of ester esters are commercially used as the flavoring agents and lower esters are ued as the solvents. for example, n-octyl acetate is used as orange flavor, amyl and isoamyl acetate is used for banana flavor,methyl butyrate is used for apple or pineapple flavor, amyl valerate is used for apricot flavor and benzyl acetate is used for jasmine flavor Shantanu Lanke

what is the relation between velocity and pressure...... if they both are directly proportional.......what do you say about venture meter where velocity increses when pressure decreases? in venturimeter u measure the pressure perpendicular to the flow which is proportional to height. if velocity increases, diameter of pipe dereases and hence the height. therefore u get a reduced pressure. To explain this we need to consider two major equations Let us take 1. Bernoulli's equation: P + (Rho)gy + (1/2)(Rho)v^2 const. 2.Continuity equation: Which is to maintain constant flow rate QA1v1 A2v2 Considering flow is happening through a tapering pipe. P pressure Rho density g gravity y height Q Flow rate (Kg/cu.metre) A1 area of cross-section-1 A2 area of cross-section-2 v1 velocity at cross-section-1 v2 velocity at cross-section-2 Section 1 Larger than Section 2 So when flow happens from section 1 to section 2 the area is decresing so the velocity will increase to maintain the constant flow rate by continuity equation. So if you take Bernoulli's equation, to maintain constant value at one side the datum/height or the pressure has to be increased. So Area decreases-->Velocity will increase-->Pressure increases. So velocity and Pressure are inversely proportional unless the Datum/Height is same. Hope this solves your query ah.yehia Mai i know what is the reason for having 2different system for pressure units i.e, kg/cm squ. 1 bar = 1.019368kg/cm2 1kg/cm2 = 0.9810bar http://wiki.xtronics.com/index.php/Pressure_Conversion_Table ah.yehia

plz let me know the clear meaning of heat capacity & specific heat The specific heat is the amount of heat per unit mass required to raise the temperature by one degree Celsius. The relationship between heat and temperature change is usually expressed in the form shown below where c is the specific heat. The relationship does not apply if a phase change is encountered, because the heat added or removed during a phase change does not change the temperature. https://www.facebook.com/photo.php?fbid=566235160089579&set=a.4798264320637 86.109797.479381242108305&type=1&theater The heat capacity of a defined system is the amount of heat (usually expressed in calories, kilocalories, or joules) needed to raise the system's temperature by one degree (usually expressed in Celsius or Kelvin). It is expressed in units of thermal energy per degree temperature. To aid in the analysis of systems having certain specific dimensions, molar heat capacity and specific heat capacity can be used. To measure the heat capacity of a reaction, a calorimeter must be used. Bomb calorimeters are used for constant volume heat capacities, although a coffee-cup calorimeter is sufficient for a constant pressure heat capacity. B.H what is purging?? Purging is the process of adding a substance to an open system or releasing it, to go from one concentration to another, be it moisture, oxygen, or product purity. Purging a system to an inert state will render it safe from combustion or explosion as long as the inert state is maintained by blanketing.

The two main situations encountered in purging a chemical process include: •Start up, where equipment containing air is to be placed into service •Shut down, where equipment containing combustible gas or vapor is to be withdrawn from service B.H why vacuum pressure created in gas condensate distillation plant (re boiler & column) when ur vapors condense to liquid, pressure exerted by the the vapors is reduced and at the boiling point VP = atm press. therefore when vapor ondenses VP is reduced and u get a vacuum. how the air filled in a cycle tube was not coming out? check this http://www.madehow.com/Volume-2/Bicycle.html#b

CAN U EXPLIN ME THE DIFFERENCE BETWEEN specific heat and heat capacity The specific heat is the amount of heat per unit mass required to raise the temperature by one degree Celsius. The relationship between heat and temperature change is usually expressed in the form shown below where c is the specific heat. The relationship does not apply if a phase change is encountered, because the heat added or removed during a phase change does not change the temperature. https://www.facebook.com/photo.php?fbid=566235160089579&set=a.4798264320637 86.109797.479381242108305&type=1&theater The heat capacity of a defined system is the amount of heat (usually expressed in calories, kilocalories, or joules) needed to raise the system's temperature by one degree (usually expressed in Celsius or Kelvin). It is expressed in units of thermal energy per degree temperature. To aid in the analysis of systems having certain specific dimensions, molar heat capacity and specific heat capacity can be used. To measure the heat capacity of a reaction, a calorimeter must be used. Bomb calorimeters are used for constant volume heat capacities, although a coffee-cup calorimeter is sufficient for a constant pressure heat capacity. The unit for specific heat is J/(g*K). The unit for heat capacity is J/K. It should be simple how to go from one to another. The biggest source of confusion is that a lot of people use the terms interchangeably. Often times heat capacity is used to describe specific heat capacity, molar heat capacity, and volumetric heat capacity, even though that is not exactly correct. B.H wts ment by leadent heat of frost point When water condenses, cools, or freezes, the temperature of the environment around the water rises because latent is changed to sensible heat. Latent heat is chemical energy stored in the bonds that join water molecules together and sensible heat is heat you measure with a thermometer. When latent heat is changed to sensible heat, the air temperature rises. When ice melts, water warms, or water evaporates, sensible heat is changed to latent heat and the air temperature falls. Table 1 shows the amount of heat consumed or released per unit mass for each of the processes.

can you please say physical and chemical properties of ethanol check this http://www.ucc.ie/academic/chem/dolchem/html/comp/ethanol.html http://en.wikipedia.org/wiki/Ethanol_(data_page)

why cavitation is not happening in reciprocating pump......?if it is because of some extra devise why cant we make centrifugal pump...like that? Cavitation is the formation and then immediate implosion of cavities in a liquid – i.e. small liquid-free zones ("bubbles") – that are the consequence of forces acting upon the liquid. It usually occurs when a liquid is subjected to rapid changes of pressure that cause the formation of cavities where the pressure is relatively low. Reciprocating pumps subject liquids to high pressures and not low pressures. Cavitation occurs when the pressure on a liquid drops below the vapor pressure for the liquid or when gas is otherwise introduced to a pump such that it disrupts the flow of the liquid through the pump. Positive displacement pumps trap a quantity of liquid (or gas) and then increase the pressure by pushing (displacing) it into the discharge pipe. External pressure pushes the liquid into the pump chamber which then is made smaller before the pump chamber discharges its contents. If any gas enters the pump chamber along with a liquid it is simply compressed along with the liquid. Positive displacement pumps work just fine with both gases and liquids - although when gases are being compressed it is usually necessary to cool the pump chamber which heats up quite a bit during the almost adiabatic compression step of the pump. Cavitation does not occur in part because the pressure in the pump chamber is almost completely uniform. If the compression chamber drops below the vapor pressure of a liquid being pushed into it, the external pressure will continue to push the liquid in, then when the pump begins to decrease the volume, the valve allowing the liquid to enter will close and the volume of the contents is decreased until the pressure rises back above the vapor pressure of the liquid and it condenses in the pump chamber. A centrifugal pump uses a rotating impeller to increase the pressure and flow rate of a fluid. In centrifugal pumps, pressure is added by increasing the kinetic energy of the liquid and then, in essence, "throwing" the liquid into the discharge pipe where the higher kinetic energy liquid pushes on the liquid ahead of it to increase pressure. As the impeller moves through the liquid being pumped, it pushes on the liquid ahead of it, imparting additional kinetic energy to it. The liquid behind the impeller, however, actually experiences a little bit of a drop in pressure as the impeller tries to move away from it. Because liquids are fairly incompressible, this usually does not create any problem and the internal pressure of the liquid is sufficient to keep it in contact with the backside of the impeller. If the drop in pressure is low enough that the pressure drops below the vapor pressure of the liquid at the temperature present in the pump, the liquid will begin to vaporize. Once gas is present in the pump, it begins to cavitate - the liquid separates from the back of the impeller especially near the tips. For this reason, introducing air or other gas into the liquid can cause cavitation, even if the pressure never drops below the vapor pressure of the liquid being pumped. This is also why centrifugal pumps are usually "primed" prior to being started up - to get all, or at least most, of the gas out of the line so that the pump won't cavitate. ah.yehia

Can you please say what are the safety precautions to be taken for preparation of ethyl alcohol from molasses fermentation Fermentation is the process of culturing yeast under favorable thermal conditions to produce alcohol. This process is carried out at around 35–40 °C. Toxicity of ethanol to yeast limits the ethanol concentration obtainable by brewing; higher concentrations, therefore, are usually obtained by fortification or distillation. The most ethanol-tolerant strains of yeast can survive up to approximately 15% ethanol by volume. To produce ethanol from starchy materials such as cereal grains, the starch must first be converted into sugars. In brewing beer, this has traditionally been accomplished by allowing the grain to germinate, or malt, which produces the enzyme amylase. When the malted grain is mashed, the amylase converts the remaining starches into sugars. For fuel ethanol, the hydrolysis of starch into glucose can be accomplished more rapidly by treatment with dilute sulfuric acid, fungally produced amylase, or some combination of the two. Any good suggestion for my thesis? The topic should be related to petroleum refining because i am a scholar of a certain petroleum refining company. thank you Platforming Catalytic reforming is a chemical process used to convert petroleum refinery naphthas, typically having low octane ratings, into high-octane liquid products called reformates which are components of high-octane gasoline (also known as high-octane petrol). Basically, the process re-arranges or re-structures the hydrocarbon molecules in the naphtha feedstocks as well as breaking some of the molecules into smaller molecules. The overall effect is that the product reformate contains hydrocarbons with more complex molecular shapes having higher octane values than the hydrocarbons in the naphtha feedstock. In so doing, the process separates hydrogen atoms from the hydrocarbon molecules and produces very significant amounts of byproduct hydrogen gas for use in a number of the other processes involved in a modern petroleum refinery. Other byproducts are small amounts of methane, ethane, propane, and butanes. i need picture of High Temperature and low temperature shift converter in ammonia plant, can you send me this picture please. check this is very useful http://www.mediafire.com/download/2cys6yzxiiwyv6t/HT_and_LT.rar

ah.yehia 1micron=-----???------m micron equal 1×10^−6 of a metre http://en.wikipedia.org/wiki/Micrometre

what is hagen and poiseuille laws? Hagen–Poiseuille equation is a physical law that gives the pressure drop in fluid flowing through a long cylindrical pipe. The assumptions of the equation are that the flow is laminar viscous and incompressible and the flow is through a constant circular crosssection that is significantly longer than its diameter. It is also known as the Hagen– Poiseuille law, Poiseuille law and Poiseuille equation. V = ( pi * p * R4 ) / ( 8 * n * l ) V = Volume per Second P = Pressure Difference Between The Two Ends R = Internal Radius of the Tube n = Absolute Viscosity L = Total Length of the tube https://www.facebook.com/photo.php?fbid=568439276535834&set=a.4798264320637 86.109797.479381242108305&type=1&theater B.H what is the difference between heat and temperature THE DIFFERENCE BETWEEN TEMPERATURE AND HEAT: There is a fundamental difference between temperature and heat. Heat is the amount of energy in a system. The SI units for heat are Joules.Heat is transferred through radiation, conduction and convection. The amount that molecules are vibrating, rotating or moving is a direct function of the heat content. When first added to a substance, energy might be concentrated in one atom, but this one will soon bump into others and spread the energy. Eventually, every atom or molecule in the substance will move a bit faster. When the added energy is spread throughout a substance, it is then called heat energy, thermal energy. TEMPERATURE: Temperature is the MEASURE of the AVERAGE molecular motions in a system and simply has units of (degrees F, degrees C, or K). Notice that one primary difference between heat and temperature is that heat has units of Joules and temperature has units of (degrees F, degrees C, or K). Another primary difference is that energy can be transported without the temperature of a substance changin.But, as a general statement , as heat energy increases, the temperature will increase. If molecules increase in vibration, rotation or forward motion and pass that energy to neighboring molecules, the measured temperature of the system will increase. B.H which software should i use to draw process flow diagrams ? it can help you http://www.edrawsoft.com/flowchart.php

what is difference between pressure and pressure energy . and also explain relation between pressure and area , pressure energy and area #Pressure is defined as force per unit area. It is usually more convenient to use pressure rather than force to describe the influences upon fluid behavior. The standard unit for pressure is the Pascal, which is a Newton per square meter. #Pressure as Energy Density: Pressure in a fluid may be considered to be a measure of energy per unit volume or energy density. For a force exerted on a fluid, this can be seen from the definition of pressure. The most obvious application is to the hydrostatic pressure of a fluid, where pressure can be used as energy density alongside kinetic energy density and potential energy density in the Bernoulli equation. http://water.me.vccs.edu/courses/CIV240/lesson9.htm B.H how the problem of flooding in a distillation column is confronted in an industry? Flooding Flooding is brought about by excessive vapour flow, causing liquid to be entrained in the vapour up the column. The increased pressure from excessive vapour also backs up the liquid in the downcomer, causing an increase in liquid holdup on the plate above. Depending on the degree of flooding, the maximum capacity of the column may be severely reduced. Flooding is detected by sharp increases in column differential pressure and significant decrease in separation efficiency.

controlling flow-rates of feed and refluxes and controlling tower temperature to control flow of vapor and liquid into the column ah.yehia What is the diffrence between vapour & steam vapor is of any volatile liquid while steam is the vapor of only water at its boiling point vapor need not to occur only at boiling pt whereas stem is always at boiling pt of water of greater. Steam refers to the gaseous phase of water which is formed when water boils while water vapour refers to the gas phase of water. The difference between steam and water vapour is that water vapour can be produced from the evaporation or boiling of liquid water or from the sublimation of ice while steam is only formed from boiling water. ah.yehia

Difference between vacuum and pressure Differences: To get the difference between pressure and vaccum , one must use both the terms in a common situation. So to clear this, have an example of piston-bottle arrangement(very much like the case in reciprocating or cylinder engine).

So in this case whenever user applies a pressure over it, the inner air gets densed and in the other end, if user tries to take piston out , in the same condition, the inner air gets less denser. Means by the second activity , a VACCUM is going to create in between the bottle. So we can deduce that vaccum is reciprocal to pressure, means more the pressure => more the air density in between => No longer Vaccum Exist but Negating the Pressure => Less the air density in between => Vaccum is established. Such thing can be observed in Injections, if you block the needle end and try to elongate the other end by akichning it. http://entrance-exam.net/forum/general-discussion/difference-between-pressurevacuum-what-formula-details-about-conversion-units-110068.html ah.yehia how to creat a place of artificial gravity...........?what r the different things to be considered.. Check these links http://en.wikipedia.org/wiki/Artificial_gravity http://wiki.answers.com/Q/How_do_you_make_artificial_gravity http://www.youtube.com/watch?v=jkgrVL69mmA http://curious.astro.cornell.edu/question.php?number=65 ah.yehia why does the sphere gives more surface area and volume than any other shaped object Check these links http://en.wikipedia.org/wiki/Surface_area https://www.facebook.com/media/set/?set=a.573647859348309.1073741835.4793812 42108305&type=1 Ah.yehia

CAN U EXPLAIN ABOUT SOLID LIQUID EXTRACTION AND LIQUID LIQUID EXTRACTION? Leaching is one of many solid-fluid separation processes that are carried out in the chemical, mineral and related industries. In fact, it is one of the oldest unit operations in the chemical industries. The fundamental principle behind leaching is theremoval of a soluble material from an insoluble, permeable solid phase. The soluble fraction, solid or liquid, may exist mechanically in the pore structure of the insoluble material or chemically combined with that material. This soluble material is removed through dissolution in a dissolving solvent. The most familiar example of leaching is the extraction of tea and coffee, and most importantly mineral recovery. The rate of leaching (extraction) is affected by many physical and chemical phenomena. Mass transfer and equilibrium phenomena obviously playmajor roles. The process of leaching consists of the following steps: (i) The solvent diffuses into the solid phase; (ii) The diffused solvent dissolves the solutes (i.e. transfer the solute to the liquid phase). Leaching is always followed by solvent recovery, which involves another mass transfer operation; such as filtration. Liquid-Liquid Extraction Process: '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' There are basically three steps in the liquid-liquid extraction process: (1) contact the solvent with the feed solution; (2) separate the raffinate from the extract; (3) separate the solvent and the solute. Step 3, recovery of the solvent and solute, is left to be done by some other process such as distillation. In liquid-liquid extraction, the feed is the original solution. The feed solution, containing the solute (the material that will be dissolved), is fed to the lower portion of the extraction column (See the pic). The solvent (the material that dissolves the solute) is added near the top. Because of density differences, the lighter feed solution tends to rise to the top while the heavier solvent sinks to the bottom. As the two streams mix, the solvent dissolves the solute. Thus, the solute, which was originally rising with the feed solution, actually reverses its direction of flow and goes out with the solvent through the bottom of the column. This new solution, consisting of solvent and solute, is called the extract. The other chemical in the feed stream, now free of the solute, goes out the top as the raffinate. The raffinate and extract streams are not soluble in each other and will layer out. https://www.facebook.com/photo.php?fbid=566713113375117&set=pb.479381242108 305.-2207520000.1374516311.&type=3&theater .. M.S Gve me some seminar topcs. CHECK this post which posted on you wall page :( https://www.facebook.com/IamCheEng/posts/574618782584550 ah.yehia

What is the vacuum distillation? Vacuum distillation is a method of distillation whereby the pressure above the liquid mixture to be distilled is reduced to less than its vapor pressure (usually less than atmospheric pressure) causing evaporation of the most volatile liquid(s) (those with the lowest boiling points). This distillation method works on the principle that boiling occurs when the vapor pressure of a liquid exceeds the ambient pressure. Vacuum distillation is used with or without heating the mixture. Vacuum distillation is distillation at a reduced pressure. Since the boiling point of a compound is lower at a lower external pressure, the compound will not have to be heated to as high a temperature in order for it to boil. Vacuum distillation is used to distill compounds that have a high boiling point or any compound which might undergo decomposition on heating at atmospheric pressure. The vacuum is provided either by a water aspirator or by a mechanical pump. A vacuum distillation set-up differs from a simple distillation with the inclusion of a securely attached round bottom flask as the receiving flask and a vacuum line connected to the vacuum adaptor.The vacuum line in this particular set-up is connected to a "water-trap", which is a side-arm flask. The water-trap itself is connected to a water aspirator . Preferrably, you would connect the vacuum line from the vacuum adaptor to a mechanical vacuum system. https://www.facebook.com/photo.php?fbid=573981919314903&set=a.4798264320637 86.109797.479381242108305&type=1&theater B.H what is E and Z nomanclature in organic chemistry these links are useful http://en.wikipedia.org/wiki/E-Z_notation http://www.learnchem.net/orgo/alke_ctez.shtml http://www.chemguide.co.uk/basicorg/isomerism/ez.html ah.yehia Write the name of chemical which is used for natural gas drying operation? Glycol dehydration is a liquid desiccant system for the removal of water from natural gas and natural gas liquids (NGL).Glycols typically seen in industry include triethylene glycol (TEG), diethylene glycol (DEG), ethylene glycol (MEG), and tetraethylene glycol (TREG). TEG is the most commonly used glycol in industry

Why combustion is not an reversable reaction Irreversible Reactions As children, we learned that chemical reactions occurred when reactants reacted with each other to form products. These unidirectional reactions are known as irreversible reactions. In other words, irreversible reactions are reactions where the reactants convert to products and where the products cannot convert back to the reactants. These reactions are essentially like baking. The ingredients, acting as the reactants, are mixed and baked together to form a cake, which acts as the product. This cake cannot be converted back to the reactants (the eggs, flour, etc.), just as the products in an irreversible reaction cannot change into the products. As stated above, a cake cannot be "uncooked" and so the reaction is irreversible. A real-life example of an irreversible reaction is combustion. Combustion usually involves the burning of an organic compound, like a hydrocarbon, and oxygen to produce carbon dioxide and water. Since water is stable in its polyatomic state, like below, it will not react with the other product, CO2, to form the reactants. Combustion can take the following form: CxHy + O2 → CO2 + H2O ah.yehia can i get the photos of valves https://www.facebook.com/photo.php?fbid=565273996852362&set=a.4798264320637 86.109797.479381242108305&type=1&theater What is the significance of the nitrogen system in the plant? many reactions are to be onducted under nitrogen atmosphere. especially reactions inolving the oxygen sensitive products or reactants. also for deoxygenation of reaction solvents in order to remove dissolved oxygen. Does any one can explain the difference between Liquid-Liquid Extraction and distillation process in the separation of liquid mixture? distillation is the process which separates 2 or more liquids based on their relative volatilities while LLE separates 2 or more liquids based on their distribution coefficients. how can I make design for Reactor (PFR) using polymath program? http://en.wikipedia.org/wiki/Plug_flow_reactor_model where can I get the complete information about INSTRUMENTATION AND PROCESS CONTROL you can check this http://www.pc-education.mcmaster.ca/Instrumentation/go_inst.htm

can anyone explain difference between upstream and downstream process in oil and gas industry? The petroleum industry is usually divided into three major components: Upstream, midstream and downstream, though midstream operations are usually included in the downstream category.

Upstream - Upstearm oil sector is a term commonly used to refer to the searching for and the recovery and production of crude oil and natural gas. The upstream oil sector is also known as the exploration and production (E&P) sector. The upstream sector includes the searching for potential underground or underwater oil and gas fields, drilling of exploratory wells, and subsequently operating the wells that recover and bring the crude oil and/or raw natural gas to the surface. MiddleStream - The midstream industry processes, stores, markets and transports commodities such as crude oil, natural gas, natural gas liquids (LNGs, mainly ethane, propane and butane) and sulphur. DownSTream - The downstream oil sector is a term commonly used to refer to the refining of crude oil, and the selling and distribution of natural gas and products derived from crude oil. Such products include liquified petroleum gas (LPG), gasoline or petrol, jet fuel, diesel oil, other fuel oils, asphalt and petroleum coke. http://wiki.answers.com/Q/What_is_the_difference_between_upstream_and_downstr eam_in_a_refinery http://globalvalveandcontrols.com/blog/index.php/2012/02/upstream-downstreammidstream-whats-the-difference/ best regards ah.yehia what is the main difference bet absorption and adsorption sep process??? these links are useful http://wiki.answers.com/Q/What_the_difference_between_absorption_and_adsorptio n_and_sorption http://www.diffen.com/difference/Absorption_vs_Adsorption ah.yehia Does anyone know where I can find the roughness of BWG tubes? http://www.engineeringtoolbox.com/surface-roughness-ventilation-ducts-d_209.html

wt is the difference between heat and temperature. There is a fundamental difference between temperature and heat. Heat is the amount of energy in a system. The SI units for heat are Joules.Heat is transferred through radiation, conduction and convection. The amount that molecules are vibrating, rotating or moving is a direct function of the heat content. When first added to a substance, energy might be concentrated in one atom, but this one will soon bump into others and spread the energy. Eventually, every atom or molecule in the substance will move a bit faster. When the added energy is spread throughout a substance, it is then called heat energy, thermal energy. TEMPERATURE: Temperature is the MEASURE of the AVERAGE molecular motions in a system and simply has units of (degrees F, degrees C, or K). Notice that one primary difference between heat and temperature is that heat has units of Joules and temperature has units of (degrees F, degrees C, or K). Another primary difference is that energy can be transported without the temperature of a substance changin.But, as a general statement , as heat energy increases, the temperature will increase. If molecules increase in vibration, rotation or forward motion and pass that energy to neighboring molecules, the measured temperature of the system will increase. i want to download aspen plus for windows 8 or chemcad can u help me with a torrent link or some other way to download it pls reply asap!!!! you can download AspenOneV8.0.torrent https://www.facebook.com/photo.php?fbid=576067575773004&set=a.4798264320637 86.109797.479381242108305&type=1&relevant_count=1 Can someone please differenciate between absorption and adsorption in terms of mass transfer absorption is a physical or chemical phenomenon or a process in which atoms, molecules, or ions enter some bulk phase – gas, liquid, or solid material. This is a different process from adsorption, since molecules undergoing absorption are taken up by the volume, not by the surface (as in the case for adsorption). Adsorption is the adhesion of atoms, ions, or molecules from a gas, liquid, or dissolved solid to a surface. This process creates a film of the adsorbate on the surface of the adsorbent.

can we use nitrogen for stripping in a crude column,if so how and not why yes we can use N2 for stripping since its an inert gas, its mechanism is based on the intersction of [email protected] with the dissolved gas. http://www.cheresources.com/invision/topic/15755-crude-oil-stripping-using-nitrogento-remove-h2s/

CAN ANY ONE OF TELL WHAT ARE THE CHARACTERISTICI OF IDEAL LIQUID ? 1. Steady flow...... it is all moving at the same speed. What goes into a tube comes out of a tube. It doesn't speed up in one place and slow down in anaother. 2. Incompressible flow..... liquids are hard to compress, they behave almost like solids. the molecules are very close together so they repel each other if you try to compress them 3. Again there are no velocity gradients or changes in velocity due to the drag of the liquid molecules on each other. they all move at the same speed. 4. They do not form vortices and move in circles, they move linearly, respond to the push of the molecules behind them. Related to compressibilty and viscosity, I imagine. http://laporanipa.wordpress.com/tag/characteristics-of-an-ideal-fluid/ ah.yehia How jet mill works and describe its industrial uses? Jet Mill works on micronizing of products using compressed air instead of mechanical impacts due to which the micro size is very fine. Micro milled products are obtained in microns after the material collide with each other and reduce themselves by attrition and collision.which consists of grinding chamber takes the shape of an oval loop of pipe 25 to 200 mm in diameter and 1.2 to 2.4 m in height .Feed enters near the bottom of the loop through a venture injector. Centrifugal classification of the ground particles takes place at the upper bend of the loop. The operating gas enters the grinding chamber through energizing nozzles placed in the wall. A discharge opening in the inner wall leads to a cyclone separator and a bag collector of the product. https://www.facebook.com/photo.php?fbid=578131378899957&set=a.4798264320637 86.109797.479381242108305&type=1&theater B.H what is surging in compressor? Centrifugal and axial compressors will surge when forward flow through the compressor can no longer be maintained, due to an increase in pressure across the compressor, and a momentary flow reversal occurs. Once surge occurs, the reversal of flow reduces the discharge pressure or increases the suction pressure, thus allowing forward flow to resume again until the pressure rise again reaches the surge point. This surge cycle will continue until some change is made in the process or compressor conditions. ah.yehia

what type of radiation is primarily responsible for the production of ions in ionosphere? The ionosphere is the upper part of the atmosphere, extending from about 50 km to 2000 km above the Earth's surface. The part we are interested in for EM transmission is the lower 500 kilometers. In the ionosphere, radiation from the sun (primarily X-rays, ultraviolet and particles) bombard gas molecules and cause them to release electrons. These are called "free electrons" and they are negatively charged. The molecules that lose the electrons become postively charged. The name for charged molecules or atoms is "ions" and these positive ions are what the ionosphere is named after. The free electrons and ions cause HF radiation that is moving upward to bend back toward the earth, an effect called refraction. This bending allows the signals to travel back down to the surface at ranges well over the horizon, giving HF radiation its unique long range characteristics. When radiation from the sun is no longer present during nighttime, many of the electrons join back with the ions, but some remain free throughout the night. An important parameter for EM propagation is the amount of free electrons that are present; this is called the "electron density". The higher the electron density, the more HF radiation is bent toward the surface. Can anybody tell me a book regarding Disc type reactor. The spinning disc reactor (SDR) is a novel continuous system suited to highly volatile reactions. Where a reaction is highly exothermic and occurs in seconds, quenching is rapid, reducing side reactions and by-product formation. The low inventory of the system allows aggressive reactions to be handled safely. The system is continuous and a significant volume of product, 10kg an hour, is manufactured over time. https://www.facebook.com/photo.php?fbid=580053425374419&set=a.4798264320637 86.109797.479381242108305&type=1&theater B.H does steam(saturated or superheated) follows gas laws? superheated steam may follow but saturated doesnt Shantanu Lanke I need any book about PVC-nano filler URGently http://www.nantopaint.com/attachments/article/212/Issue11%20NanoTechNovember.p df What is the best insulating material for reactor with 80 deg C operating temperature? polystyrene can be used. Shantanu Lanke

Which one of the following is an indication of pump cavitation? A. Pump motor amps are pegged high. B. Pump discharge pressure indicates zero. C. Pump motor amps are fluctuating. D. Pump discharge pressure indicates shutoff head. Cavitation is defined as the process of formation and disappearance Cavitation is defined as the process of formation and disappearance of the vapour phase of a liquid when it is subjected to reduced and subsequently increased pressures.Cavitation is a thermodynamic change of state with mass transfer from liq pp ( uid to vapor phase and visa versa ( bubble formation & collapse). The cause of cavitation in pumps is usually due to insufficient NPSH (Net Positive Suction Head) energy on the suction side of the pump. NPSH is the energy required to push the liquid into the pump. This can be caused by: (NOTE: Change the bullets below into checkmarks.) • Having the pump at too high of a distance above the fluid source • Having too small of a diameter of suction pipe • Having too long of a distance of suction pipe • Having too many fittings on the suction pipe • Handling a liquid with a low vapor pressure • Running the pump too fast. The first problem is a reduction in the pumping capacity of the pump. If the pump is unable to keep up with the incoming flow, then an overflow situation may occur. Cavitation also causes damage to the pump. The collapsing vapor bubbles can cause excessive vibration, which can cause rotating parts, such as the impeller, to contact nonrotating parts, such as the wear plates or wear rings, causing damage. Excessive vibration may also cause premature failure to mechanical seals and bearings. Cavitation can also damage the wetted components themselves from contact with the imploding vapor bubbles. https://www.facebook.com/photo.php?fbid=579308622115566&set=a.4798264320637 86.109797.479381242108305&type=1&theater B.H What is liquid and gas heat capacity cofficients of HBF4, BF3, and HF Check these links http://www.matweb.com/search/datasheet.aspx?matguid=a8d4500ab271440ca4e26ef 2f9e2df71&ckck=1 http://answers.yahoo.com/question/index?qid=20100423113748AAXnjx7 http://pubs.acs.org/doi/abs/10.1021/je980064d?journalCode=jceaax who khow about "chem e car"'s system? it's about choose chemical reaction to make car move

what is the difference between distillation and evaporation evaporation: change of state from and liquid to gas. distillation: method of separating a solution to its own components that involves boiling and condensation

Evaporation. The easiest example is water. Water molecules are in constant motion. Some molecules move fast enough to escape into the air on their own. Sweat evaporates from your skin to cool you. When you air dry your hands in a bathroom, it is evaporation that makes the water go away. Many liquids will evaporate into the air, not just water. Distillation. Lets look at water again, though you can distill most any liquid. When you heat water you can make it boil. The boiling water will go into the air as steam. (In this way evaporation and distillation are similar) That steam can be captured and cooled down again to make liquid water. The cool part is that if there is anything else in the water that you don't want, it will stay behind when you boil the water. So if you are really thirsty and only have a bottle of salt water, you can use distillation to make clean water. Scientist use distillation to separate liquids from impurities, like salt, but also to separate liquids that are mixed in with each other. ah.yehia Need some Help Regarding Reverse Osmosis(RO) Process and how Semipermeable membrane works? reverse osmosis is the process of forcing a solvent from a region of high solute concentration through a semipermeable membrane to a region of low solute concentration by applying a pressure in excess of the osmotic pressure. The largest and most important application of reverse osmosis is the separation of pure water from seawater and brackish waters; seawater or brackish water is pressurized against one surface of the membrane, causing transport of salt-depleted water across the membrane and emergence of potable drinking water from the low-pressure side. A semipermeable membrane, also termed a selectively permeable membrane, a partially permeable membrane or a differentially permeable membrane, is a membrane that will allow certain molecules or ions to pass through it by diffusion and occasionally specialized "facilitated diffusion". Shantanu Lanke

I am sureshbabu, final year chemical engineering department. Can you please any one tell me how to remove the fluoride content in water using adsorption. For this technique, activated alumina, bone char and clay adsorption media are the most developed. During the past two decades, extensive research has focused on a number of alternative adsorbents, some exhibiting improved fluoride sorption performances while at the same time do not alter the quality of treated water. ftp://ftp.ecn.purdue.edu/vmerwade/class/GDT/uploaded_documents/Files%20from%20 Dr.%20Das/F%20removal%20by%20alum.PDF http://www.sciencedirect.com/science/article/pii/S187203580602001X Shantanu Lanke wat is the difference between evaporation and crystallization? Crystallization it may be defined as a process which separates a pure solid in the from of its crystals from a solution. Evaporation Process of separating any substance from its solution by removing water is called evaporation. http://www.funqa.com/chemistry/3970-Chemistry.html http://www.webelements.com/forum/node/201 ah.yehia f u consider a fluid in sea water, the density of that fluid will not be same at every location..............can you tell me why? due to the concentration gradient due to difficulty in diffusion see sea water is salty bcz minerals from earth rocks are carries by the rivers to the sea. and at different places in earthcrust different amts of minerals are present so each river will carry different amts of salt with it and in liquids diffusion occurs at a slow pace as that in gaseous phase. Shantanu Lanke

Why PFR is better than CSTR...? & why conversion in PFR is more compare than CSTR...? PFR: All calculations performed with PFRs assume no upstream or downstream mixing, as implied by the term "plug flow". Reagents may be introduced into the PFR at locations in the reactor other than the inlet. In this way, a higher efficiency may be obtained, or the size and cost of the PFR may be reduced. A PFR typically has a higher efficiency than a CSTR of the same volume. That is, given the same space-time, a reaction will proceed to a higher percentage completion in a PFR than in a CSTR. CSTR: At steady-state, the flow rate in must equal the mass flow rate out, otherwise the tank will overflow or go empty (transient state). While the reactor is in a transient state the model equation must be derived from the differential mass and energy balances. The reaction proceeds at the reaction rate associated with the final (output) concentration. Often, it is economically beneficial to operate several CSTRs in series. This allows, for example, the first CSTR to operate at a higher reagent concentration and therefore a higher reaction rate. In these cases, the sizes of the reactors may be varied in order to minimize the total capital investment required to implement the process. It can be seen that an infinite number of infinitely small CSTRs operating in series would be equivalent to a PFR. Shantanu Lanke what is the difference between unbound moisture content and free moisture content? Unbound moisture: Unbound moisture exerts a vapor pressure equivalent to that of the free liquid. Thus in a non-hygroscopic material, all the liquid is unbound and in a hygroscopic material, the unbound moisture is the liquid in excess of the equilibrium moisture content (EMC), corresponding to saturation humidity. Free moisture: Free moisture is the liquid in excess of the equilibrium moisture content at a given temperature and humidity. Thus under condition of saturation humidity, the free moisture is the same as the unbound moisture, but in certain circumstances the free moisture may consist of both unbound and bound moisture. Shantanu Lanke What is TEAL? Any idea? it's Tri Ethyl Aluminium Liquid.

in crystallization process......solubility increses with increse in temp...bt for mnso4 solubility is decresing with temp....can you tell me why? MnSO4 is a sparingly soluble compound. as u increase the temp., water decreases due to evaporation and net conc. of MnSO4 increases to supersaturation. which crystallizes it out. Shantanu Lanke how can we soften the lattice adhesion below the carpet Lubricated contact sets other demands on the materials surface structure, and the main issue is to retain the protective lubrication thickness and avoid plastic deformation. This is important because plastic deformation raises the temperature of the oil or lubrication fluid and changes the viscosity. Shantanu Lanke I am a student Of Chemical Engineering, studing in Thadomal Shahani Engineering College. I Am currently in my final year of BE. I am doing a Project on "Design OF Sulphur Condenser". Now i am stuck on a calculation. I thought U guys can help me. i just wanted to know the antoine constant of sulphur i.e. A B C . i have found of hydrogen sulphide and sulphurdioxide but i am stuck at this. It would be of great help if u people can do anything about it u cannot get antoine const. for sulfur since its a solid. however antoine constants for sulfur dioxide and hydrogen sulfide are as follows: SO2:(177.7-263K) A=3.48586 B=668.225 C=-72.252 SO2:(263-414.9K) A=4.37798 B=966.575 C=-42.071 H2S:(138.8-212.8K) A=4.43681 B=829.439 C=-25.412 H2S:(212.8-349.5K) A=4.52887 B=958.587 C=-0.539 Shantanu Lanke

What is the methods of Natural Gas Liquefaction? The liquefaction process involves removal of certain components, such as dust, acid gases, helium, water, and heavy hydrocarbons, which could cause difficulty downstream. The natural gas is then condensed into a liquid at close to atmospheric pressure (maximum transport pressure set at around 25 kPa (3.6 psi)) by cooling it to approximately −162 °C (−260 °F). LNG achieves a higher reduction in volume than compressed natural gas (CNG) so that the energy density of LNG is 2.4 times greater than that of CNG or 60% of that of diesel fuel.[1] This makes LNG cost efficient to transport over long distances where pipelines do not exist. Specially designed cryogenic sea vessels (LNG carriers) or cryogenic road tankers are used for its transport. LNG is principally used for transporting natural gas to markets, where it is regasified and distributed as pipeline natural gas. It can be used in natural gas vehicles, although it is more common to design vehicles to use compressed natural gas. Its relatively high cost of production and the need to store it in expensive cryogenic tanks have hindered widespread commercial use. Currently there are 4 Liquefaction processes available: C3MR (sometimes referred to as APCI): designed by Air Products & Chemicals, Incorporation. Cascade: designed by ConocoPhillips. Shell DMR Linde Shantanu Lanke

.in distillation where we need to use partial condenser and where to use final condenser......and what is the main difference we observe when using these two Partial condenser is the simplest vapour-liquid separation device for gaseous mixtures. It can only be used when the boiling points of the substances are so different that essentially only one of them will condense into a liquid under suitable conditions. In a total condenser te temperature is lowerd to a level on which all gasses turn to liquids. with a partial condenser you can separate gasses on there dew point. It means that the temperature is set to a level on wich a one or several gasses leave the partial condenser as a liquid and the others as a gas. Shantanu Lanke can you say what are the olechemicals obtained from Sesame oil by the transesterification of the seasame oil. Shantanu Lanke

can u xplin me about thermodynamic steam trap....what is the purpose of strainer thr? Thermodynamic traps work on the difference in dynamic response to velocity change in flow of compressible and incompressible fluids. As steam enters, static pressure above the disk forces the disk against the valve seat. The static pressure over a large area overcomes the high inlet pressure of the steam. As the steam starts to condense, the pressure against the disk lessens and the trap cycles. This essentially makes a TD trap a "time cycle" device: it will open even if there is only steam present, this can cause premature wear. If non condensable gas is trapped on top of the disc, it can cause the trap to be locked shut. Purpose of strainer is to remove the dust particles if any. Shantanu Lanke what is the difference btwn foot valve and non return valve? A Foot Valve for a pump is a one way check valve. It lets water flow in one direction only/ towards the pump. It is placed at the bottom of the suction pipe, just behind the filter screen. This is normal for an above ground pump, not a submersible pump. The purpose is to keep the pump from loosing it's prime. Check valves or non return valves are two-port valves, meaning they have two openings in the body, one for fluid to enter and the other for fluid to leave. There are various types of check valves used in a wide variety of applications. Shantanu Lanke what is the difference btwn HETP and HTU? HETP arises from the same concept of equilibrium stages as does the theoretical plate and is numerically equal to the absorption bed length divided by the number of theoretical plates in the absorption bed (and in practice is measured in this way). The height of a transfer unit (HTU) is a measure of the separation effectiveness of the particular packings for a particular separation process. Shantanu Lanke what you have to do when the solution is more viscous and forms a layer at the bottom of crystallizer? in that case swenson walker crystallizer can be used. Shantanu Lanke

WHAT IS THE DIFFERENCE BETWWEN IMPELLER AND PROPELLER? An impeller is a rotor inside a tube or conduit used to increase (or decrease in case of turbines) the pressure and flow of a fluid. Aircraft propellers or airscrews convert rotary motion from piston engines, turboprops or electric motors to provide propulsive force. Shantanu Lanke cant we make self priming centrifugal pump....if so why? Typically, a liquid pump can't simply draw air until the feed line and pump fill with the liquid that requires pumping. An operator must introduce liquid into the system to initiate the pumping. This is called priming the pump. Loss of prime is usually due to ingestion of air into the pump. The clearances and displacement ratios in pumps for liquids and other more viscous fluids usually cannot displace air due to its lower density.

Shantanu Lanke Help in providing Isocyanide prepartion technology ??????? The first isocyanide, allyl isocyanide was prepared in 1859 by the chemist Lieke from the reaction of allyl iodide and silver cyanide.[9] Normally the alkylation of an alkali metal cyanide gives a nitrile, but the silver ion protects the carbon end of the cyanide. Commonly, isocyanides are synthesized by the reaction of primary amines with dichlorocarbene or by dehydration of a formamide with phosphorus oxychloride. RNH2 + :CCl2 + 2 NaOH → RNC + 2 NaCl + 2 H2O RNHC(O)H + POCl3 → RNC + "PO2Cl" + 2 HCl The Hofmann isocyanide synthesis is a chemical test for primary amines based on their reaction with potassium hydroxide and chloroform as dichlorocarbene precursors to foul smelling isocyanides. Another route to isocyanides is by reaction of organolithium compounds with oxazoles and benzoxazoles: The benzoxazole gets deprotonated at the 2-position by n-butyllithium. The lithium compound is in chemical equilibrium with the 2-isocyanophenolate which can be captured by an electrophile such as an acid chloride. Being an ester the formed isocyanate in the example above behaves uncharacteristically with reportedly a mild cherry smell. Another synthetic route towards an isocyanide is 1) condensation of an amine with formic acid, yielding a formamide, and 2) dehydrating this formamide. Phosgene (or a synthon or precursor such as diphosgene) can be used in combination with formamide to yield isocyanides. Shantanu Lanke

what you have to do if the solvent is more volatile in crystallization operation? teduce the temperature of heating. if the solvent is too volatile, crystallization can take place even at the room temperature. Shantanu Lanke

is surge occurs only in centrifugal compressors????if sooo what abt the rest...why it is nt happening to them Stall is found in dynamic compressors, particularly axial compressors, as used in jet engines and turbochargers for reciprocating engines. Shantanu Lanke tell me Which book should I refer for gas absorption with chemical reaction? Oura, K.; V. G. Lifshits; A. A. Saranin; A. V. Zotov; M. Katayama (2003). Surface Science, An Introduction. Berlin: Springer. ISBN 3-540-00545-5. ^ a b c Rettner, C.T; Auerbach, D.J. (1996). "Chemical Dynamics at the Gas-Surface Interface". Journal of Physical Chemistry 100 (31): 13021–13033. doi:10.1021/jp9536007. ^ a b c Gasser, R.P.H.; (1985) An introduction to chemisorption and catalysis by metals, Clarendon Press, Oxford ^ Norskov, J.K. (1990). "Chemisorption on metal surfaces". Reports on Progress in Physics 53 (10): 1253–1295. doi:10.1088/0034-4885/53/10/001. ^ a b Clark, A.; (1974); The Chemisorptive Bond: Basic Concepts, Academic Press, New York and London

You can refer any book from the mentioned above. Shantanu Lanke what are the basic properties of crayogenic fluids cryogenic fluids condense oxygen from air and reduce the percentage of oxygen in air resulting in asphyxia. also contact with them may cause severe frostbites. the show leidenfrost effect, which can cause cryo spills. Shantanu Lanke what do u mean by a solvate? and where will they form Solvation, also sometimes called dissolution, is the process of attraction and association of molecules of a solvent with molecules or ions of a solute. As ions dissolve in a solvent they spread out and become surrounded by solvent molecules. Shantanu Lanke

what is ment by monatomic molecules In physics and chemistry, monatomic is a combination of the words "mono" and "atomic," and means "single atom." It is usually applied to gases: a monatomic gas is one in which atoms are not bound to each other. At standard temperature and pressure (STP), all of the noble gases are monatomic. These are helium, neon, argon, krypton, xenon and radon. The heavier noble gases can form compounds, but the lighter ones are unreactive. All elements will be monatomic in the gas phase at sufficiently high temperatures. The only mode of motion of a monatomic gas is translation (electronic excitation is not important at room temperature). Thus in an adiabatic process, monatomic gases have an idealised γ-factor (Cp/Cv) of 5/3, as opposed to 7/5 for ideal diatomic gases where rotation (but not vibration at room temperature) also contributes. Also, for ideal monatomic gases: the molar heat capacity at constant pressure (Cp) is 2.5 R = 20.8 JK-1mol-1 (4.97 calK1mol-1); the molar heat capacity at constant volume (Cv) is 1.5 R = 12.5 JK-1mol-1 (2.98 calK1mol-1); where R is the gas constant. http://wiki.answers.com/Q/What_are_the_monatomic_molecules ah.yehia what is the importance of specific gravity Specific gravity is important in that it can be converted to density. Specific gravity compares the mass of a given volume of material to the mass of the same volume of water. This produces a value that is equal to density at one temperature and close to the value of density at other temperatures. Density is one of the key characteristics of materials. http://answers.yahoo.com/question/index?qid=20101201172637AAnGNYf it is important because it helps determine what the mineral you are looking for is http://wiki.answers.com/Q/What_is_the_importance_of_specific_gravity ah.yehia

What is Hot Tapping mean? its is the method of making a connection to existing piping or pressure vessels without the interruption of emptying that section of pipe or vessel. This means that a pipe or tank can continue to be in operation whilst maintenance or modifications are being done to it. Shantanu Lanke

what are the diff betn shell-tube H.E and double pipe H.E? difference between double pipe HE and shell and tube HE Double pipe heat exchanger consists of two concentric pipes of different diameters.One pipe is for hot fluid and another is for cold fluid.Both may have same flow direction(COCURRENT) and opposite direction(COUNTERCURRENT). Shell and tube heat exchanger consists of a shell in which large number of parallel tubes are present.One fluid hot or cold flow in shell and other hot or cold flow in the tubes. Also in case of shell & tube(S&T) the hot fluid will have more turbulence than in double pipe heat exchanger (HE) since there are no of tubes within a shell the area for convective heat transfer is considerably increased. so these are much more preferred. B.H difference between kerosine and gasoline...? Kerosene: its structural formula is C8H8.C14H30. it is a heating fuel. its boiling point ranges 175-325.C. Gasolene: it contains carbon atoms ranging C4H10-C13H28. it is a motor fuel. Its boilin point ranges 40-220.C http://wiki.answers.com/Q/What_is_the_difference_between_kerosene_and_gasoline ah.yehia what is the major diffrence between "azeotropic" and "extractive distillation".? check these links http://wiki.answers.com/Q/What_is_the_difference_between_extractive_distillation_a nd_azeotropic_distillation http://www.differencebetween.net/science/chemistry-science/differences-betweenazeotropic-and-extractive-distillation/

ah.yehia Which distillation is stubble for higher viscous fluids? steam distillation Shantanu Lanke

i need more xplanation abt differences btwn extractive and azeotropic distillation Extractive distillation is defined as distillation in the presence of a miscible, high boiling, relatively non-volatile component, the solvent, that forms no azeotrope with the other components in the mixture. In azeotropic distillation, entrainer is immiscible with the feed. Shantanu Lanke check these links http://wiki.answers.com/Q/What_is_the_difference_between_extractive_distillation_a nd_azeotropic_distillation http://www.differencebetween.net/science/chemistry-science/differences-betweenazeotropic-and-extractive-distillation/ ah.yehia What is difference between fouling and scaling? fouling can be the deposition of any foreign material. for example if u have steel pipes, fouling may be caused due to the deposition of caco3 if the water is hard. while scaling is the deposition of the derivative of the pipe material such as rust. Fouling is the accumulation of unwanted material on solid surfaces to the detriment of function.

Scaling is the deposited material formed my the pipe material itself by the chemical reaction which is unwanted. Shantanu Lanke i wanna some information about cooper silver ionisation as a disinfection method Check this link .... I think it could help http://www.lenntech.com/processes/disinfection/chemical/disinfectants-copper-silverionization.htm

Admin : Tally r u plz snd me shorts notes 4 axial n radial flow impeller http://www.lutz-pumpen.de/en/Service/Things-to-Know-2/Foerderradform-Laufradoder-Rotor.aspx ah.yehia

Could you please describe the difference of polytropic and isentropic efficiencies of gas compressor? Thank you very much in advance. In general, positive displacement compressors are calculated on the adiabatic cycle (see API 618 Reciprocating Compressors), and rotordynamic compressors on the polytropic cycle (see API 617 Centrifugal and Axial Compressors). As with everything there are exceptions, single stage or air compressors are often calculated on the isentropic cycle. Solar Turbines uses the isentropic cycle for their range of centrifugal compressors. Polytropic efficiency is always greater than adiabatic efficiency, how much greater being dependent on the process conditions (adiabatic exponent and pressure ratio). For Centrifugal Compressors, the actual stage ratings are developed from test curves and converted to head and efficiency. On a Polytropic basis, the curves do not vary regardless of actual gas, whereas on an isentropic or adaibatic basis, the base rating curve would be invalid due to differences in cp and k of the actual vrs test gas. Since gas machines have impeller base ratings on a polytropic basis, it is simpler to state the performance on a polytropic basis rather than change it to an isentropic basis after it has been calculated. This is especially true when MW,K,Z type calculations are employed. One exception is of course air comprssors which have historically often been stated on an isentropic basis, but of course always use the same gas (air). Furher complicating, If a Mollier Chart (or Real gas equations) are used to calculate performance, the polytropic impeller ratings must be converted to adiabatic head and efficiency in order to compute delta H along constant entropy lines. Again, since historically gas compressors state performance as polytropic, the results are converted back to a polytropic basis once the overall calculation is done. The conversion is pretty easy since Work = Polytropic Head/Polytropic eff and also = Adiabatic Head / Adiabatic eff. As long as you aren't going to change the gas, performance can be stated on either an adiabatic or polytropic basis. All of the above comments apply to how manufacturers use base ratings when calculation machine performance. Work transfer and thus power calculation is path dependent (i.e. work transfer is not a thermodynamic property). Polytropic process accounts for the path (small stages) where as isentropic only considers the start and end point. Using polytropic efficiency gives a more accurate calculation of power required.

Could you please describe the difference of polytropic and isentropic efficiencies of gas compressor? Thank you very much in advance. look at thermodynamics references for example may this book help you, page 123 http://my.safaribooksonline.com/book/mechanicalengineering/9781139567169/11dot4-the-corecompressor/definitions_of_efficiency__ise#X2ludGVybmFsX0J2ZGVwRmxhc2hSZWFkZXI/ eG1saWQ9OTc4MTEzOTU2NzE2OS8xMjM= ah.yehia i have try to found the activation energy and reaction constant for thet wo reaction below but i cant found any result , plz if u can help me CH4+H2O→CO+3H2 CO+H2O→CO2+H2 these reactions are happened in ammonia process CH4+H2O→CO+3H2 At high temperatures (700 – 1100 °C) and in the presence of a metal-based catalyst (nickel), steam reacts with methane to yield carbon monoxide and hydrogen. pressure from 32 to 40 bar CO+H2O→CO2+H2 The process is often used in two stages, stage one a high-temperature shift (HTS) at 350 °C (662 °F) and stage two a low-temperature shift (LTS) at 190–210 °C (374–410 °F).[2] Standard industrial catalysts for this process are iron oxide promoted with chromium oxide for the HTS step and copper on a mixed support composed of zinc oxide and aluminum oxide for the LTS step. CO + H2O CO2 + H2 delta (H)@298 = -41 kJ.mol-1 CH4 + H20 CO + 3H2 delta (H)@298 = 206 kJ.mol-1 ah.yehia My professor assigned me a report regarding Cr(III). Can you help me? check this http://www.lenntech.com/periodic/elements/cr.htm

difference between cracking and pyrolosis? Pyrolysis : The decomposition of a compound on heating in absence of air is known as pyrolysis. cracking: is the breakdown of large organic compounds by use of a catalyst and low temperature to form fewer different compounds ah.yehia Is there any material related to paint technology..? I've some papers .. but if you need books I think These 2 pages will be more useful for you Admin B.E.B.O http://www.mediafire.com/?qdx33t943j29fjb https://www.facebook.com/AllAboutChemcalEngineering?ref=ts&fref=ts https://www.facebook.com/Che.Engineering?ref=ts&fref=ts

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"what is - & + feedback?" well positive feedback is when a part of the output is given back to the input so that the output increases more. this is done to produce oscillations. and negative feedback is when a part of the output is given back to the inputs so that the output decreases more. this is done to stabilize the gain of an amplifier. positive feedback is also known as regenerative feedback and negative feedback is also known as degenerative feedback. http://www.edaboard.com/thread22978.html ah.yehia İ will begin in a aerosol can factory as a chemical engineer. Do you have some information about aerosols and aluminium can I hope this reference can help http://www.mediafire.com/?ueoi2qben01cbcb Admin : Tally

can you please inform me the difference between partial condensor and total condensor used in distillation column In a total condenser the temperature is lowered to a level on which all gasses turn to liquids. with a partial condenser you can separate gasses on there dew point. It means that the temperature is set to a level on which a one or several gasses leave the partial condenser as a liquid and the others as a gas. ah.yehia

what is the check point of pump starting? DO YOU MEAN STARTING UP ? * Ensure power supply is isolated. * Check pump rotates freely by hand. ie. there are no obstructions in the pump or drive motor. * Open any isolating valves and ensure pump is flooded. ie. release any air-locks in the pump or pipework. * Start the pump briefly to check for correct direction of rotation. The correct rotation should be indicated by an arrow on the pump or drive motor - if not, refer to operating manual. * Note: Some pumps have screw-on impellers which may be loosened if the pump is run in reverse direction. * On start-up, it is advisable to partially close a valve in the pump discharge line to limit the initial flow surge. Also monitor the power taken by the drive motor. * Once running, the discharge valve should be progressively opened until the required flow rate and pressure is obtained, ensuring that the power taken is within the maximum rating of the drive motor. * The absorbed power is dependent on the pump performance and the properties of the fluid being pumped. ie. specific gravity, viscosity and entrained solids etc. * Remember that most centrifugal pumps must not be run 'dry' of process liquid because of probable damage to the shaft seal or bearings on a magnetic drive unit. ah.yehia Why should people interested in chemical Engineering field? Please Describe me look at these plz http://www.cheresources.com/content/articles/students/why-become-a-chemicalengineer http://www.ceb.cam.ac.uk/pages/why-study-chemical-engineering.html http://web.mit.edu/cheme/academics/whycheme.html good luck ah.yehia i wanna attempt to construct a viable home based ammonia or urea production unit. using methane or LPG. In your opinion, is this possible to do profitably? And if it is cud u send me links to some literature tht myt help me out. this attach will help you http://www.mediafire.com/download/w7ftn158rtbinx3/ammonia.rar ah.yehia

Explain the process of extraction of petrol with flow chart. look at this may be useful https://www.facebook.com/photo.php?fbid=484403788272717&set=a.48397957831 5138.110606.479381242108305&type=3&src=https%3A%2F%2Ffbcdn-sphotos-ea.akamaihd.net%2Fhphotos-akprn1%2F72821_484403788272717_2014777249_n.jpg&size=574%2C554

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https://www.facebook.com/photo.php?fbid=485281661518263&set=a.48397957831 5138.110606.479381242108305&type=3&src=https%3A%2F%2Ffbcdn-sphotos-da.akamaihd.net%2Fhphotos-akash4%2F226645_485281661518263_1797372334_n.jpg&size=960%2C633 https://www.facebook.com/photo.php?fbid=508610592518703&set=a.48397957831 5138.110606.479381242108305&type=3&src=https%3A%2F%2Ffbcdn-sphotos-fa.akamaihd.net%2Fhphotos-akash3%2F482432_508610592518703_1203804177_n.png&size=588%2C733 https://www.facebook.com/photo.php?fbid=511668292212933&set=a.48397957831 5138.110606.479381242108305&type=3&src=https%3A%2F%2Ffbcdn-sphotos-ha.akamaihd.net%2Fhphotos-akprn1%2F164406_511668292212933_1342736341_n.jpg&size=500%2C622 http://www.afpm.org/The-Refinery-Process/ http://www.slideshare.net/jeufier/oil-refinery-processes-presentation http://www.slideshare.net/mindenn123/refinery-processdescription ah.yehia

.a black body at 3000k emits radiation,calculate the maximum emissive power & t0tal emissive power. check these links http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/radfrac.html

http://www.spectralcalc.com/blackbody_calculator/blackbody.php http://www.calctool.org/CALC/phys/p_thermo/wien ah.yehia why some pumps circulation is to the vessel and others from disharge to suction and others no circulations? i think in the first option (to vessel) 1- that may be pump around to cool or heat liquid into heat exchanges and send it again to vessel 2 - increase suction head to keep available NPSH more than required NPSH to prevent cavitation i think also in the second option (from discharge to suction) 1- increase suction head to keep available NPSH more than required NPSH to prevent cavitation 2- increase suction pressure and then decrease pressure difference between discharge and suction and this increase pump performance i think in the third option (no circulations) that you do not need it because 1- you have good NPSH always greater than required NPSH 2- you have a good performance of pump according to pressure difference between discharge and suction and this increase pump performance ah.yehia My Question is this "Heart is what type of Blood pump??" check this link plz http://www.studymode.com/essays/Comparison-Of-Different-Types-Of-Blood638087.html ah.yehia

plz tell me... the scope for chemical engineering What Is Chemical Engineering? Chemical engineering basically is applied chemistry. It is the branch of engineering concerned with the design, construction, and operation of machines and plants that perform chemical reactions to solve practical problems or make useful products.

What Is a Chemical Engineer? Like all engineers, chemical engineers use math, physics, and economics to solve technical problems. The difference between chemical engineers and other types of engineers is that they apply a knowledge of chemistry in addition to other engineering disciplines. Chemical engineers sometimes are called 'universal engineers' because their scientific and technical mastery is so broad. What Do Chemical Engineers Do? Some chemical engineers make designs and invent new processes. Some construct instruments and facilities. Some plan and operate facilities. Chemical engineers have helped develop atomic science, polymers, paper, dyes, drugs, plastics, fertilizers, foods, petrochemicals... pretty much everything. They devise ways to make products from raw materials and ways to convert one material into another useful form. Chemical engineers can make processes more cost effective or more environmentally friendly or more efficient. As you can see, a chemical engineer can find a niche in any scientific or engineering field. Chemical Engineer Salary? http://www1.salary.com/Chemical-Engineer-Salary.html ah.yehia Esterification reaction is endothermic or exothermic? it depends on the acid and the alcohol but I would say that they are mainly exothermic reactions (when the esterification generates a cyclic ester they tend to be endothermic) which are on a very displaced equilibrium towards the alcohol and the acid, so reflux and distillation are almost always needed for the reaction to proceed (with cheap alcohols the best solution is to use huge amounts of them). http://answers.yahoo.com/question/index?qid=20070509184612AAYcmsK http://community.boredofstudies.org/showthread.php?t=30164 ah.yehia

plz give me sample example on technical report writing and the full format check all of these to write a good technical report http://www.mediafire.com/download/d0wgpwgks5x7c12/report.rar http://www.slideshare.net/cpjobling/how-to-write-a-technical-report http://www.cse.iitk.ac.in/users/braman/students/good-report.html http://kevinboone.net/howto_report.html ah.yehia Is it neccessary to calculate NPSH for centerfugal pump.Tell about its significance. check these links

http://www.calculatoredge.com/calc/NPSH.htm http://chemjunction.com/onlinecalculator/fluidmechanics/npshcalculator.html http://www.engineeringtoolbox.com/npsh-net-positive-suction-head-d_634.html http://www.mediafire.com/view/?ljmdqj0mp0ft7g8 http://www.mediafire.com/view/?271r6fai2obt3bv

ah.yehia I want to all valves video so please show me the details where is download check these links on YouTube, they are very useful https://www.youtube.com/user/chaulnet?feature=watch https://www.youtube.com/user/tipvalvegroup?feature=watch http://www.youtube.com/user/fbvalve?feature=watch

http://www.youtube.com/user/taitojackie?feature=watch best regards ah.yehia

Can any one pls give of the difference between leaching and extraction. Pls give atleast 5 difference. check these links, and i'll post your question on our wall soon http://www.globalspec.com/reference/22862/203279/chapter-14-extraction-andleaching

http://wiki.answers.com/Q/What_is_the_difference_between_leaching_and_extraction ah.yehia i want to know what's pilot plant and also model plant? What's the difference between pilot plant and model plant? A manufacturing plant basically manufactures a chemical on a mass scale however a pilot plant helps to develop the process on a small scale, before a manufacturing plant is built.

Pilot plants are facilities that are created for the purpose of conducting a production process on a relatively small scale. Depending on the outcome of the evaluation of this limited process, the facility may serve as the blueprint for the creation of full-scale plant that is capable of producing much larger quantities of goods. Many businesses use the pilot plant model to work out issues of logistics and procedure before investing resources in the creation of a fully operational facility. One of the key advantages of creating a pilot plant is the ability to carefully evaluate each step in the production process. Since the plant is operating on a very small scale, the investment of resources into the project is kept at a minimum. Generally, the plant is configured to be just large enough to imitate any issues that could occur in a larger plant, but small enough to prevent the waste of raw materials, labor, and other common operational expenses. ah.yehia May you please help me finding Valves and pumps API ?? check these links http://renrocgroup.com/product-range/pump-standard/

http://valvepipeline.com/specification/api http://www.engineeringtoolbox.com/api-valve-standards-d_378.html best regards ah.yehia

Which is humidity ? If there is 44%humidity what it means ? And What is unit process ? check these websites http://www.ehow.com/list_6827719_units-used-measure-humidity_.html http://www.ehow.com/info_8442401_percentage-humidity-should-house.html http://www.intelligentanswers.co.uk/index.php?topic=2299.0 http://wiki.answers.com/Q/Why_does_it_feel_hot_in_humid_weather ah.yehia if maybe you could provide me with some information on the terephthalic acid production process. In particular, the Invista technology. check these links http://www.indorama.net/EN/ourBusinesses/ourBusiness_PTA_Product.php http://www.davyprotech.com/Default.aspx?cid=577 ah.yehia Disadvantage of solral energy ? check these links plz http://www.powersourcesolar.com/5151/ http://alternate-power.org/solar-power-advantages-and-disadvantages/ ah.yehia pls write (post) about Alkyd Resin. Check these links http://www.britannica.com/EBchecked/topic/15764/alkyd-resin http://www.google.com/patents/US4045392 http://processflowsheets.blogspot.com/2011/04/alkyd-resin-manufacturing.html

ah.yehia

what r the differnce between adsorption and absorption ? Adsorption - the binding of molecules or particles to a surface the filling of pores in a solid. The binding to the surface is usually weak and reversible. Just about anything including the fluid that dissolves or suspends the material of interest is bound, but compounds with color and those that have taste or odor tend to bind strongly. Absorption -is a physical or chemical phenomenon or a process in which atoms, molecules, or ions enter some bulk phase - gas, liquid or solid material. Difference: Adsorption is a process where the molecule/particle adheres only to the surface of the medium while absorption is a process where the molecule/particle is taken in internally and NOT on the surface Source(s): http://en.wikipedia.org/wiki/Absorption_(chemistry) http://www.diffen.com/difference/Absorption_vs_Adsorption

http://www.rpi.edu/dept/chem-eng/Biotech-Environ/Adsorb/adsorb.htm ah.yehia wet & dry bulb temperature ? check these links http://www.unitedmetal.com/2009/what-is-the-difference-between-dry-bulb-and-wetbulb-temperature/ http://www.brighthubengineering.com/hvac/39619-psychrometric-properties-dry-bulbwet-bulb-or-dew-point-temperature/ http://www.buildinggreen.com/auth/article.cfm/2012/6/29/Dry-Bulb-Wet-Bulb-What-sthe-Difference/ best regards ah.yehia will they have any information on distillation automation? and also isomerization of paraffins 5 and 6 carbon atoms and which improve the anti-knock? http://www.polmon.com/wp-content/uploads/2012/11/distillation.pdf http://ntnu.diva-portal.org/smash/get/diva2:123504/FULLTEXT01.pdf

If i am using vaccuum distillation..what wl be its purpose? decreasing pressure then you can separate at low temperature because when pressure decrease boiling point decrease too note : if you increase temperature with atmospheric pressure crude may thermal cracked so you need to decrease boiling point

ah.yehia any mechanical design Multibed adiabatic fixed-bed reactor with interstage heat exchange and collector https://www.facebook.com/photo.php?fbid=568687629844332&set=a.479826432063786.1097 97.479381242108305&type=1&theater

B.H you can fined example ammonia converter, check this is useful http://www.mediafire.com/download/9rpobqlrixht5lc/NH3_converter.rar ah.yehia Can a plate heat exchanger do the task of multiple shell and tube heat exchangers? Compact Design Plate heat exchangers are small, yet efficient. It is possible to have a Plate exchanger with the same thermal capacity of a Shell & Tube heat exchanger five times its size. The compact design conserves space in the heat exchanger environment, as well as material cost. Plate heat exchangers are available in a variety of sizes and materials to suit many different applications and industries. http://www.deltathx.com/contentpg.aspx?itemid=655 http://instrumentations.blogspot.com/2011/04/advantages-and-disadvantages-ofplate.html ah.yehia can you give me informations about PROCESS OF OFFSET NEGATIVE you can check this http://www.dynodan.com/printing-process-explained/lithography-files/offset-platetechnology.html

B.H

Why combustion is not an revetsable reaction Irreversible Reactions As children, we learned that chemical reactions occurred when reactants reacted with each other to form products. These unidirectional reactions are known as irreversible reactions. In other words, irreversible reactions are reactions where the reactants convert to products and where the products cannot convert back to the reactants. These reactions are essentially like baking. The ingredients, acting as the reactants, are mixed and baked together to form a cake, which acts as the product. This cake cannot be converted back to the reactants (the eggs, flour, etc.), just as the products in an irreversible reaction cannot change into the products. As stated above, a cake cannot be "uncooked" and so the reaction is irreversible. A real-life example of an irreversible reaction is combustion. Combustion usually involves the burning of an organic compound, like a hydrocarbon, and oxygen to produce carbon dioxide and water. Since water is stable in its polyatomic state, like below, it will not react with the other product, CO2, to form the reactants. Combustion can take the following form: CxHy + O2 → CO2 + H2O ah.yehia Difference betn fan,blower,compressor Difference bewteen fan,blower,compressor: a #blower consists of a fan and channels air from the exhaust side of the fan directing it through a ducting system and delivering the air to a specific location,A blower is a machine for moving volumes of a gas with moderate increase of pressure A #compressor is a machine for raising a gas - a compressible fluid - to a higher level of pressure A #fan moves large amounts of gas with low increase in pressure. B.H designe of distillation coulmn>>diameter>>Height>>>Thickness of the cylindrical section>>> these reports are very useful http://www.mediafire.com/download/xc5o0o0ybmbaoig/distillation.rar best regards ah.yehia

Difference b/w vapours and gas? The word vapor in its natural state is a solid or liquid at room temperature. However, a gas in its natural state at room temperature would still be a gas. Example: 1) steam would be a vapor because at room temperature, it would be water, which is a liquid. 2) Nitrogen (a gas) at room temperature would still be in a gaseous state.

To make it more simple, a vapor is a substance which has experienced a phase change. Whereas, a gas is a substance which has not, and will not experience a phase change. Gas is a state of matter while vapor is not. A gas is a substance above its critical temperature but below its critical pressure, while a vapor is a substance above its boiling point temperature. A vapor is a gas. To me, the word, "vapor" suggests a gas that was formed by evaporation of something that is a liquid at room temperature. For example, water vapor. It also connotes a gas that can be seen. So hen a gas condenses to liquid, two physical processes are possible. In one, the phase change occurs via nucleation and growth- small liquid drops spontaneously form and evaporate, but if a drop is larger than some critical radius, it will continue to grow ('nucleates'). This is the most common phenomenon of a gas-liquid (or liquid-solid) phase transition. Less common is 'spinoidal decomposition', which leads to coexistence of a gas and liquid phase- critical opalescence. I don't know if a spinoidal decomposition can occur in the liquid-solid transition.

SO Gas is one of the 4 states of matter which are solid, liquid, gas and plasma, vapor does not classify as such. It is just a substance it is gaseous form. Vapor can turn back and forth into liquid and solid states but a gas cannot Gases cannot be see while vapors are visible Vapors settle down on ground while gases do not http://answers.yahoo.com/question/index?qid=20111012182349AA4tF3D ah.yehia i need more info about production of sulphonic acid using conc sulforic acid http://www.wisegeek.com/what-is-fuming-sulfuric-acid.htm i need some best samples of cv thanks in advance http://www.kent.ac.uk/careers/cv.htm

What is cost index for the year 2013 according to chemical engineering.? 569.5 Preliminary April 2013 568.3 March 2013 Current Economic Trends: April preliminary CEPCI Preliminary data for the April 2013 CE Plant Cost Index (CEPCI; the most recent available) indicate that the composite index increased by 0.2% compared to the final March value, reversing three consecutive decreases in the months prior. The higher numbers included increases in a number of subindices, such as process machinery, pumps & compressors and heat exchangers & tanks. The April 2013 preliminary PCI index value stands at 4.4% lower than the corresponding final PCI value from April 2012. Meanwhile, the latest Current Business Indicators from IHS Global Insight moved in both directions, with CPI output inching higher while CPI value of output http://www.scribd.com/doc/121019752/CEPCI

ah.yehia qus-in case of shell and tube heat exchanger if one tube is get damaged what we should do? Remove a tube or hole tube boundle what is more economical yup, there is more economical way that is plugging tubes which leak but we can plug number of tubes to 25% total number of tubes check these movie and website

http://www.youtube.com/watch?v=2i0EphMTAPc http://www.energy-tech.com/article.cfm?id=17791 ah.yehia what kind of trouble shoot found in compresor ..??? Check these links http://www.portlandcompressor.com/compressor/trouble-shooting.aspx http://www.sifbrake.com/techtips/100-aircompts ah.yehia

What are the major differences in tubes and pipes The primary difference between pipe and tubing is how the size is designated. Pipe is designated by a "Nominal Pipe Size" based upon the ID (inside diameter) of the most common wall thickness. Tubing is designated by the measured OD (outside diameter). For Example: A 3/4 inch iron pipe has an OD of 1.050 inches, while a 3/4 inch steel tube has an OD of 0.75 inches. The Copper industry calls all cooper tubular products "Tubes" but they designate a "Type". Each type has specified OD and ID dimensions ah.yehia What is steam trapping?? A steam trap is a device used to discharge condensate and non condensable gases with a negligible consumption or loss of live steam. Most steam traps are nothing more than automatic valves. They open, close or modulate automatically. Others, like venturi traps, are based on turbulent 2-phase flows to obstruct the steam flow. The three important functions of steam traps are: Discharge condensate as soon as it is formed. Have a negligible steam consumption. Have the capability of discharging air and other non-condensable gases. https://www.facebook.com/photo.php?fbid=564380096941752&set=a.479826432063786.1097 97.479381242108305&type=1&theater

B.H A device which is used to remove silt. The simplest form of steam trap is a disc or short solid pipe nipple with a small hole drilled through it installed at the lowest point of the equipment. Since steam condensate will collect at the lowest point and live steam is about 1200 times greater in volume than this hot liquid, condensate is effectively removed and steam is blocked. However, the vast majority of steam traps in current operation are of the mechanical or thermostatically operated design. Mechanical and thermostatic steam traps basically open when condensate and inert gases need to be removed, and close when there is only steam present. Steam traps work best when sized specifically for the application they are used on. Generally it is better to oversize, as they will still discharge condensate when present and close or obstruct for live steam. However an oversized steam trap may wear quickly, waste energy (use steam), and if drastically oversized can cause process issues. Shantanu Lanke

.Do you have a list of all dimensionless number used in chemical engineering? these links are useful http://www.mycheme.com/dimensionless-groups-in-chemical-engineering/ http://jodha-chemicalengineering.blogspot.com/2010/02/important-dimensionlessnumber-in.html best regards ah.yehia Difference btw chiller and cooling tower? check these links, they are useful http://aircoolfan.danielcadams.com/the-difference-between-a-chiller-and-a-coolingtower/ http://answers.yahoo.com/question/index?qid=20061008080150AAxTJGC best regards ah.yehia If surge and stall occur in centrifugal compressor simultaneously how to overcome or troubleshoot such situation? Surge is a flow instability that results in a global collapse of flow through the compressor. Compressors do not continue to operate or flow once surge has occurred. Surge should be avoided. Surge is not the rough operation, vibration, pulsation, or noise that develops at low flow conditions. Surging is a momentary reversal of flow.When the pressure in the centrifugal comp. increases,the mass flow rate decreases.There is a limit up to which the pressure can be increased,then after the flow becomes instable and momentary reversal of flow take place,vibrations are produced and mechanical damage occurs. ah.yehia Can you please tell me about the compressors in briefly ....? A gas compressor is a mechanical device that increases the pressure of a gas by reducing its volume. Compressors are similar to pumps: both increase the pressure on a fluid and both can transport the fluid through a pipe. As gases are compressible, the compressor also reduces the volume of a gas. Liquids are relatively incompressible; while some can be compressed, the main action of a pump is to pressurize and transport liquids.

which one is strongest passivation agent?why a)sodium nitrate b)sodium nitrite c)hydrazine hydrate d)hydrogen peroxide its sodium nitrite since ift forms on the pyrolytic reduction of sodium nitrate. its not affected easily by environmental factors such as air and water. Shantanu Lanke i am searching about semicoductors, what is chemical amplification resist? and what is the limitation of this technology? Photoresists used in production for DUV and shorter wavelengths require the use of chemical amplification to increase the sensitivity to the exposure energy. This is done in order to combat the larger absorption at shorter wavelengths. Chemical amplification is also often used in electron-beam exposures to increase the sensitivity to the exposure dose. In the process, acids released by the exposure radiation diffuse during the postexposure bake step. These acids render surrounding polymer soluble in developer. A single acid molecule can catalyze many such 'deprotection' reactions; hence, fewer photons or electrons are needed. Acid diffusion is important not only to increase photoresist sensitivity and throughput, but also to limit line edge roughness due to shot noise statistics. However, the acid diffusion length is itself a potential resolution limiter. In addition, too much diffusion reduces chemical contrast, leading again to more roughness. The following reactions are an example of commercial chemically amplified photoresists in use today: photoacid generator + hν (193 nm) → acid cation + sulfonate anion [sulfonate anion + hν (193 nm) → e− + sulfonate e− + photoacid generator → e− + acid cation + sulfonate anion The e− represents a solvated electron, or a freed electron that may react with other constituents of the solution. It typically travels a distance on the order of many nanometers before being contained; such a large travel distance is consistent with the release of electrons through thick oxide in UV EPROM in response to ultraviolet light. This parasitic exposure would degrade the resolution of the photoresist; for 193 nm the optical resolution is the limiting factor anyway, but for electron beam lithography or EUVL it is the electron range that determines the resolution rather than the optics. Shantanu Lanke I wish study Azeotropic distilation you explain with me http://en.wikipedia.org/wiki/Azeotropic_distillation

what is the difference between phase equilibrium and temperature equilibrum? phase equilibrium is when all the 3 phases of matter coexist at a particular temp and pressure. temperature or thermal equilibrium is when any two components exist at same temperature. Shantanu Lanke why shorter wavelengths is required for the production? what is the problem that lead the researchers to invent chemical amplification? This particular parameter is closely related to the thickness of the applied photoresist, with thinner layers corresponding to shorter wavelengths, permitting a reduced aspect ratio and a reduced minimum feature size. Shantanu Lanke

. im writing this message to ask u about the nitrogen that is commun used in plant. Please can u give me data about how is used in storages and in purge and for example when the product is solid and need to be exit from the process how the nitrogen is used as an inert environment int hat case. Starting from the source of the Nitrogen, for example let it be an air separation unit produces O2 & N2, nitrogen is transported by means of pipe lines & simply stored in vertical storage vessel that has the coverage capacity of the plant requirements, & from this tank or vessel we have one outlet which has the same pressure of the vessel & we can say it will be the high pressure nitrogen distribution, & from that outlet line there is another branch that contains a pcv to control & reduce the pressure for the other branch (other outlet) & we can say it will be the low pressure nitrogen distribution system. So now we have one inlet to the storage tank & two outlet (HP & LP) each one for different uses, & In case of we have a solid material & u want to put it in an inert environment, there will be a bin or silo down side or under the reactor from which the product is discharged, let it named the discharge bin & that bin has an external pipe connected with a shut-off valve which is opened when u need to put or pressurize that bin with nitrogen till an exact pressure value, always it will be that same pressure for the reactor, but u r pressurizing that bin in the same time there is an isolation valves between it & the reactor, when the delta P between the bin & the reactor reaches ZERO or the minimum value, then u can discharge the material from the reactor to the bin safely in an inert nitrogen environment. ... For nitrogen purging usage ... almost all big gas lines have a small branch connected to it with a check valve its direction is from outside, inlet to the big line as filling it with nitrogen till a pressure which is not necessary to exceed high value may be 2 or 3 bar is enough for purging the line & release any unwanted contamination, in some times there is no need to make a pressure & the line should be opened to the atmospheric pressure to release all unwanted impurities & gases. M.S

Can explain the relation between wet bulb temp, dry bulb temp, dewpoint, and humidity, effect one on another ? CHECK these links http://www.engineeringtoolbox.com/dry-wet-bulb-dew-point-air-d_682.html http://www.brighthubengineering.com/hvac/39619-psychrometric-properties-dry-bulbwet-bulb-or-dew-point-temperature/ http://answers.yahoo.com/question/index?qid=20090721091947AAfSmIE ah.yehia What is the difference between free energy and gibbs free energy. check these links

http://www.differencebetween.com/difference-between-gibbs-free-energy-and-vshelmholtz-free-energy/ http://answers.yahoo.com/question/index?qid=20111013034152AA6ZIUh http://physics.tamuk.edu/~suson/html/3333/GibbsEnergy.html http://www.physicsforums.com/showthread.php?t=691232 ah.yehia why we add steam into the coloumn before to start distillation process? to purge the column from oxygen and to heat it .. this is preparing unit for start up ah.yehia what is the difference between micro and macro balance? micro balance is the balance in micro to miligram quantities while macrobalance is the balance in gram to kg quantities.

Shantanu Lanke does modes of heat transfer(conduction and covection) affected by gravity? yes. Shantanu Lanke

do i have any chance that you mention the process of production of hexamehylenediamine? Hexamethylenediamine (HMDA, boiling point: 204 oC, melting point: 41oC) is used in the synthesis of nylon, and it is manufactured from butadiene. In the process, butadiene first adds one mole of hydrogen cyanide at 60 oC with a nickel catalyst via both 1,2 and 1,4 addition to give, respectively, 2-methyl-3-butenonitrile and 3-pentenonitrile in a 1:2 ratio. Isomerization of the 2-methyl-3-butenonitrile to 3pentenonitrile takes place at 150oC. Then more hydrogen cyanide, more catalyst, and a triphenylboron promotor react with 3-pentenonitrile to form methylglutaronitrile and mostly adiponitrile. The adiponitrile is formed from 3-pentenonitrile probably through isomerization of 3pentenonitrile to 4-pentenonitrile and followed by addition of hydrogen cyanide. CH2=CHCH=CH2 + 2HCN ----> NC(CH2)4CN Extraction and distillation is necessary to obtain pure adiponitrile. Even then the hexamethylenediamine made by hydrogenation of adiponitrile must also be distilled through seven columns to purify it before polymerization to nylon. Hexamethylenediamine is produced from adiponitrile by hydrogenation. NC(CH2)4CN + H2 ----> H2N(CH2)6NH2 Evaporation of the reaction product of formaldehyde and ammonia also produces hexamethylenetetramine. Hexamethylenediamine is used in the production of nylon 6,6 and mainly in making phenol-formaldehyde resins, where it is known as hexa. It is also used as a urinary antiseptic (Urotropine) as well as in the rubber industry and for the manufacture of the explosive cyclonite. M.Salah Why reflux is require in distillation?What is it's advantage? it efficiently separates the two or more components that have less diff in their bp. The more reflux provided for a given number of theoretical plates, the better is the column's separation of lower boiling materials from higher boiling materials. Conversely, for a given desired separation, the more reflux is provided, the fewer theoretical plates are required. Shantanu Lanke can be store compressed air in confined space yes. if the sapce ur gonna sore the compres air has no leakage and sufficiently rigid walls, air can be stored in it for many day with a very low decrease in pressure. Shantanu Lanke

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LIST OF QUESTIONS

Adarsh Varghese

what is the effect of High Salinity (360,000 ppm) Produced Water flowing through Carbon Steel pipes

Dileep Prajapati

What is the related equation which determine the depth of bed in reactor design?

Abdelrahman Mohamed Khalid

what's the purpose of using bin tank ? or what's the difference between normal tank & bin tank ?

Sneha Tripathi

Please sugget me a book of mass transfer operation...

Raghu Can Can

what is the difference between palm oil and refined palm oil

Hasan Salamah

what are binders for latex paint (water based paints) ?

Raghu Can Can

Er Dhaval Patel

device used for measuring low pressure gas a pitot tube b orifice c magnetic flow meter d venturi meter What type of insulating materyal is used to absorbe radation coming from radioactive material

LIST OF QUESTIONS Satyajit Mitra

can we use electric field or applied voltage to seprate a mixture of chemicals

Satyajit Mitra

how can we increase the cis or trans ratio in aromatic chemicals,especially in aldehydes.

Satyajit Mitra

is dehydrogenation of organic compound possible by electrolysis.

Omer Bin Sohail

My question is "co-catalysts are used to promote catalyst.....what we can call agents that enhance activity of cocatalysts"

Moataz Montaser

i want some information to production of white cement and its equipment

Eng-Sarah Obaid

i searched about GasChromophotometer device , but i found it analyzes gases only my problem is phenol in petrochemical wastewater discharge i want to know the conc. of it in the wastewater or any other solution

Chemical Rams

i need a "Resin or absorbent or any chemicals", Where its functioning is to completelly recovery of "Nacl" content in sea sand !

LIST OF QUESTIONS Dileep Prajapati

write a name of thermodynamic property which is same for all substances at absolute temperature?

Eng AmrMostafa

If we have 2 component A and B. A has a 90 c BP and B has a 88 BP haw to separate them by distillation?

Eng-Sarah Obaid

any one here can tell me the ways for phenol analysis in solution , and how to know the conc. of phenol in any solution

Deep Bhattacharjee

how separate hexane + water when hexane is a bottom product and water is top product in a column or dehydrator...?

Satheesh Kuppusamy

What is the lab analysis made for finding out formaldehyde and methanol in a solution?

Nagesh Marwadkar

Is pressure drop calculation is same for LIQUID & GASES.If no tell me reason.

Raghu Can Can

for corrosive fluids we use diaphragm value but for errosive fluids which type of value used?

Raghu Can Can

can we recycle expired chemicals like acids bases etc.,

LIST OF QUESTIONS Muhammad Waqar

is reflux ratio responsible for product purity or impurity in the process of distillation column?

Hiren Gohil

tell me mechanism of wiped film evaporater & thin film evaporater

Ahmed Tarek

Could I raise the optimum reflux ratio to be more than 1.55*Rmin ?

Farhan Ahmed

I want to know about the slug handling procedure in 3 phase separator

Marwa Jp

i have bsc in chemical engineering i have never practice the decipline as i am femal and due to lack of engineering jobs in my country i want to study master but confused between Msc in chemical engineering ir pharmaceutical engineering can you advice me to choose the better major

Jatin Bhoraniya

how to manufacture phthalic anhydride in industry & require equipment for production of phthalic anhydride

Roua Omer Siddiq

i want process description about production chloroethylene (VCM) the raw material is Ethylene and Clorine

LIST OF QUESTIONS Uday Kumar

what are the disadvantages of burning hydrogen/ hydrogen rich fuels in furnaces?

Raghu Can Can

Can you please say what are the safety precautions to be taken for preparation of ethyl alcohol from molasses fermentation

Jit Sarkar

what is the alternative grinding equipments of cement grinding unit instead of ball mill???

Eng.M Abdelrazek

How to use rate equation in HYSYS ?

i want to design a packed Venkata Sitarami Reddy Venkat column(distillation) any one can suggest the book

Chaitanya Rathod

how to start up and shut down any reactors ?

Raghu Can Can

,can you give examples for where do bubble cap, value, sieve tray used

Jyothi Jeevannavar ask

What is the basic concept and factors to design or size the Globe valve for a given pipe size.. say 6 inch

Anjana Virpariya ask

What is 4 step pressure swing adsorption?

LIST OF QUESTIONS

Dinakar Satya

there is a tank which has an outlet of a hole of 20mm dia and another same tank contains 2 holes of 10mm dia each...where the flow rate will be maximum and why ?

Priyanka Neeli

can we use the distillation columns with multiple refluxes? if can what are the design principles?

Jeet Sarkar

plz suggest any one about the text book of ....'instrumentation and process control' its urgent for my 7th sem.

Satadru Ghosh ask

please explain wet bulb temp. and its effect on cooling tower?

Dinakar Satya

I have a vapour mixture of 2compounds at a temaretures of 150 and 200 degrees and if we condense that mixture which will condense first aand why?

Er Dhaval patel

Why air vesal provided on pumps?

Samrin Khan

What is the actual role of streaming and rectifying column in distillation?

Jagadish Ghose

why vacuum pressure created in gas condensate distillation plant (re boiler & column)

LIST OF QUESTIONS Abuagla Alneim

can you give me informations about carbon dioxide generating (tools and all chemical material which use in this process) ?

Tinayeshe Ngara

Hey Chemical Engineers, how can I produce electricity from biogas?

Wuttichai Manoi

Can the reflux ratio be less than 1 ?

Dinakar Satya

I am doing diploma in chemical engineering and we people have do a project report on some unit {or}mass transfer operations so can u suggest me something to do that and we cant spend 15,000-20,000 rs

Dan Martinez

One of the problems is all about expansion of air at constant pressure by heating. We are still in the first law of thermodynamics in closed systems. The given is Cp and one of the reqmnts is DeltaU. DeltaU = nCvDeltaT I solved Cv using Cp - R. But our instructor told us that Cp = Cv because pressure is constant. Cp = Cv only for incompressible things right??? Am I right or he's right.

Aakash 'Teddy' Shah

can anybody tell me which is the best method to produce 1-methoxy 2propanol ?

LIST OF QUESTIONS Rajat Jaypal

i want to know that which book is very useful for GATE preparation for chemical engineering.

Priyanka neeli

What is the significance of ramp function during start up of a chemical process ?

Nikhil Ajabe

why biodiesel is not use generally

Nikhil Ajabe

pls help me for mass transfer operation book

Kim Bryan Duenas

can a control valve reduce steam pressure from 15 barg to 1 barg? Thank you!

Dileep Prajapai

Tell me chemical project economics indian author name

Fulla Al-Hiyali

Anyone can suggest good book to find specific heat capacities for an ideal gases, please

Gunasekar Kulandaivadivelu

Can any one suggest a process technology to remove Sulfur from Heavy furnace oil to produce clean HFO fuel. Process shall be other than Hydrotreating.

LIST OF QUESTIONS Chaitanya Rathod

Anyone can suggest me the journals and materials containing websites or magazines for a GATE preparations in chemical engineering ??

Clint Regondola Mohammed

What is the most common insulating material that is used for evaporators ?

Atul Gourh

In which season efficiency of cooling tower increase or decrease.can u explain ?

Ahmed Mezan

how to active biological system for etp plant.

Dew Drops

Are you have book about: manual solution of: basic principle and calculation in chemical engineer 5 th

Nidhi Sharma

What are the major differences in tubes and pipes

George Westinghouse

I NEED SOME BOOKS ABOUT GAS MANUFACTURING

Mohamed Hatem

i need help finding equations relating max gas quantity to be released safely and wind direction and speed if i'm about to design a gas dispersion system by relieving gas from a gas boot upstream crude oil storage tanks to overcome a flare problem

LIST OF QUESTIONS Mohamed Hatem

i really need any software regarding pipeline simulation as pipe phase or pip sim or any thanks in advance

Fabio Augusto

How are shell and tube heat exchangers baffles cut percentages calculated? With the area or the linear lenght of the baffle?

Abdulmohsen Azznati

What are the general types of valves used in Chemical industry? and what are the materials of construction for these types of valves?

Omer Shah

we know When We superheat the steam Temperature will increase but pressure reamains constan...How it could be possible that pressure reamins constant...we know that pressure is directly proportional to Temperature..??

Kaushalsinh Vaghela

how to work the vapour absorption machine with libr

Preet J Gandhi

I was given a project of reducing coke in the hot furnace in the manufacturing of Vinyl Chloride monomer from Ethylene Dichloride, in one of the petrochemical industry. I did it the wrong way then. I want to know the steps of accomplishing this project.

LIST OF QUESTIONS

Dinakar Satya

how the protons are being togather in the nucles of an atom even thogh they all have positive charge?

Dinakar Satya

I am trying to make a project on caluculating friction factor......give me your valuble suggitions and tell me what I need to consider when I am doing this and where can I get ful information of it.......?

Haseeb Tahir

why we account for mass flow rate while discussing surging in compressors rather than volumetric flow rate?

Sagar Patel

what is adsorption pls explain me in detail..

Sadam Shahani

Plz Briefly Describe the working principle of rotary dryer?

Priyanka Neeli

We often refer feed tray location in a dc as 'optimum feed tray'... How is it called optimum?

Chaitanya Rathod

why we consider TAU as a time constant in transfer function?

LIST OF QUESTIONS

Clint Regondola Mohammed

In designing falling-film evaporators, what heating area is being considered, the inside surface area or the outside surface area of the tubes? Let's say that the tube contains the process fluid being concentrated and the outside surface area of the tubes is exposed to the heating medium.

Abdullah Al Aftab

Next semester I will take process control course. If you can provide me any soft copy of process control books or any interactive course material available I will be very grateful.

Muhammad Abo Ul Hassan

Which one of the following is an indication of pump cavitation? A. Pump motor amps are pegged high. B. Pump discharge pressure indicates zero. C. Pump motor amps are fluctuating. D. Pump discharge pressure indicates shutoff head.

Dileep prajapati

What is the angle of vision for hemisphere?

Anjana Virpariya

What is shut off discharge pressure of centrifugal pump

‫سالم ياس‬

How is the difference between steam and vapor?

LIST OF QUESTIONS Engr Tahir Nazir

Does steam(saturated or superheated) follows gas laws?

Sagar Sudani

Waht is commarsial application of melt crystallization?

Yosen BoXer

tell me about recovery boiler in kraft's process ... and give me some idea for troubleshooting in recovery bolier process

Usman Naseem

I want the books about the types of designs for the steam reformers which are special for on-site hydrogen production such as the reformers used hydrogen fuel stations. The books includes, . Catalyst types and arrangements ii. Heat supply for reaction iii. Shell and Tube arrangments and material iv. Types of feeding, if applicable. v. What is so special about this design?

Keyur Moradiya

I want some books on petroleum refinery.

Sadam Shahani

Need some Help Regarding Reverse Osmosis(RO) Process and how Semipermeable membrane works?

LIST OF QUESTIONS

Dinakar Satya

can u explain me the properties and characteristics of a refrigerant and tell me this is true or not " ammonia have high vapor pressure so its latent heat of vaporization is more " but we r using it as an refrigerant in liquid state..... it is not getting into the form of vapour even after absorbing heat from surroundings ......how is it possible if my statement is true

Md Fasi

Need help with use of semipermeable membrane in desalination unit......also where can i get best projects and seminars

Priyanka Neeli

density and viscosity... hw r dey related for a given fluid? wrt size of particle and chemical bonds

Muhammad Arif Kabir

if vessel showing 100% LEL and want to make it 1% with N2 to start the job, which is the best, efficient and less time consuming method, and which pressure also pressuring from top or bottom??, plz share your experience and possible with calculation.

Jonard FLores

What is the best insulating material for reactor with 80 deg C operating temperature?

LIST OF QUESTIONS Dinakar Satya

what are the safety precautions to work in an refinery or any other chemical operated plant?

Dinakar Satya

tell me the assumptions and limitatios when using roults law

‫أحہٰم ٰہ ٰہہٰد قہٰأس ٰہ ٰہم‬

under which conditions we can apply laplace transform to solve the differetial equations

Hashim Ishaque

we all know about the different types of dryers , but how many types of drying are ?

Tinayeshe Ngara

I'm tasked to do a research project of my own choice and I need to know the chemical engineering processes needed to produce cosmetic creams and lotions

Soosai Raj

4" pipe line.if i send water on 5kg pressure ,how much flow of water is allowable..

Sameer Shekh

Hashim Ishaque

Why PFR is better than CSTR...? & why conversion in PFR is more compare than CSTR...? if there is valve of 1'' in a pipeline of 1'',what will happen if we change valve size from 1'' to 1.5'' ?

LIST OF QUESTIONS Dinakar Satya

in crystallization process......solubility increses with increse in temp...bt for mnso4 solubility is decresing with temp....can you tell me why?

Arvind Singh

can u suggest me a book of petrochemical polymers manufacturing??

Veynee Chinapial

Im a student of chemical engineering. I have to do my final year project and I'm not sure which one of these 2 topics to choose (1) Modeling dye sequestration by microwave activated biomass-derived adsorbents (2)Assessing different carbon capture and storage technologies which one would you advise me to do?

Kedar Wakankar

If in agitated reactor preheated water is added at 85 oC. (18000 kg) and another liquid of cp-0.35 kcal/kg C is added (18000 kg, 30 oC) What will be the temp of mixture in reactor ? There is no chemical reaction at this state in reactor. Reactor is jacketed vessel.

Dillu Dilee

Which distillation is stubble for higher viscous fluids?

LIST OF QUESTIONS Dharmesh Patel

For DCDA process What is the effective heat in waste heat boiler?

Raghu Can Can

what are the basic properties of crayogenic fluids

Manya Elhance

can any reaction have negative order.. He yes what does it signify??

Umar Zaman

When vaporisation takes place directly at the heating surface film boilng or nucleate boiling?

Edeh Kingsley Onyemaechi

How can we improve separation in distillation when separating azeotrope?

Dinakar Satya

why cant we use receprocating pumps insted of centrifugal pumps bcz both r giving flow rates ryt....so what i want to knw is what are the special resons to use centrifugal pumps at some cases

Adarsh Varghese Nacho Arvizu Arthur Shih

Antony Benedict Mohamed Eldars Santiago López Jesse Wood Chiràg Mahyavanshi

Angel YC Abdelrahman Mohamed Khalid Ahmed Yehia

Naveena Ganesh Naveena Ganesh

Raja Ehsan Raja Ehsan

Eng Amr

what is the effect of High Salinity (360,000 ppm) Produced Water flowing through Carbon Steel pipes incrustations on pipes and pumps. it's a big issue where I work Lots of corrosion. Take a look at this report: http://exchange.dnv.com/publishing/cn/GL_15.pdf Two ways to fix the problem can be either (1) add an extra layer of plastic coating inside the pipe, or (2) use sacrificial cathodic protection. Corrosion corrosion and may be scale corrosión! Corrosion. If high Salinity water pass thrgh the steel pipe den available ion salinity water contain ion like Mg ,ca ,Al etc. which is diposited on under surface of pipe due to long time so it creat after long time scaling problem coz of that ion .so after long time it reduce the heat transfer rate as well as flowrate n efficincy of steel pipe... corrosion... obviamente what's the purpose of using bin tank ? or what's the difference between normal tank & bin tank ? i think we can use this type of tanks to storage solids .. inlet from top ant outlet from bottom by gravity . if it used in liquid i think because it's easy to be cleaned due to there is fully empty by the cone (down section) shape its water storage tank To redirect excess water that cannot be stored to other storage locations or to the garden To remove stagnant water and dirt from the bottom of the tank It had cone in down section Basically a bin tank can use for waste slurry with suspended material like sewage waste with plastic and some other material for further waste treatment Sailos used for store solids

Sneha Tripathi Syed Shah Jehan Gillani Jed Bellen Sanjay Khatri Md Fasi Pandurang Chate Bikramjit Bardhan Nacho Arvizu Basher Ahmed Ahmed Marwan Ahmed Younis Er Dhaval Patel Prathap Selvam Gustavo Jimenez Gustavo Jimenez Fouad Salih Alexandre Argondizo Kary Shito Abdul Rahman Malik Ronald Allan Co Angel YC Raghu Can Can Jesse Wood Er Dhaval Patel Er Dhaval Patel

Please sugget me a book of mass transfer operation... robert treyball Faust, Bird, Lightfoot and Stewart, McCabe, Geankoplis, Treybal, Incropera Book:-Mass transfer operation..Author:-robert E traybal...all operation avilable hear.. Unit operations of chem engg maccabe and smith Mass Transfer Operation By Treybal... B.K.datta, trebal "Applied Process Design" by Ludwing & "Mass Transfer" by Maddox the one 4 Terybal is the best Coulson and Richardson - Chemical Engineering mass transfer operations for Robert E.Terybal Terybal Terybay and GK.Rai for mass transfer calculations Equilibrium Stage Separation Operation in Chemical Engineering by E. J. Henley and J. D. Seader Separation Processes by C. Judson King PRINCIPLES AND MODERN APPLICATIONS OF MASS TRANSFER OPERATIONS Mass transfer opreations by j. Benitez The acosta chuncho XD Indian writer k a gawhane is best for exams.. unit ops by geankoplis, foust, coulson and Richards Hougen watson procesos de separacion what is the difference between palm oil and refined palm oil Refining But palm oil is yellowish fatty oil obtained especially from the crushed nuts of an African palm in Refind palm oil oxidative stability and nutritional properties of crude palm oil is good

Dileep Prajapati

What is the related equation which determine the depth of bed in reactor design?

Syed Shah Jehan Gillani Arthur Shih

Sachin Kumar Mathur

Its related to pressure drop calc. the same Ergen equation...as utilized in fluidization Take a look here. It explains it pretty well. I guess you could call it the "PBR Sizing Equation" but it basically takes account of the mole balance, rate law, and stoichiometry of the system to determine its size. If you have a gas-phase reaction then you'll need to use the Ergun Equation to account for pressure drop.http://www.umich.edu/~essen/html/course/lectures/five/index.ht m#top9 Z=htu*ntu

Hasan Salamah

what are binders for latex paint (water based paints) ?

Er Dhaval Patel

Polyexposide containing reactive oxyring group is used

Mohit Rouniyar Er Dhaval Patel Savan Prajapati Nick Stroh

Is anyone have made chem-e-car ? Yes with the help of acetic acid & sodium by cardonate Yap. with help of acitic acid and vinegar.. Yes I have its a great experience

Satyajit Mitra

Amit Biswas Pintu Das Chemical Rams Suekainah Suliman Er Dhaval Patel Deddy Widiyanto

how can we increase the cis or trans ratio in aromatic chemicals,especially in aldehydes. Wittig rxn i.e. Neucleofilic addn then elimination.. by using solvents i need a "Resin or absorbent or any chemicals", Where its functioning is to completelly recovery of "Nacl" content in sea sand Ok So I'd wash it with water and then dry it. Frist wash with tape water & then distill water Only with distillation or RO

Raghu Can Can

Janardhana Swamy Randhi Sameer Pandey Fawad Malik Junaid Ahmed Jawad Rizvi Saad Shaikh Eman Abdullah Ibrahim Er Dhaval Patel Nirav Gandhi Isyaka Aminunono Vivek Juneja Roshan Tembhurne

device used for measuring low pressure gas a pitot tube b orifice c magnetic flow meter d venturi meter A A A A C C A ya u can use PITOT..TUBE Option~A pitot tube point velocity find out cheyadanikikada pitot hi hai A A pitot tube.. pitot tube A Pitot tube A A A A

Sagar Sudani Shafiqur Rahman Sajib

Pitot tube A

Hassan Elahi Rajan Rao Rathore Urmila Ambhure Muhammad Shahid Jeevarathnam Joseph Hemanta Patil Satish Dhikale Raghavendra Patil

Moataz Montaser Robin Pv

Rita Youfa

i want some information to production of white cement and its equipment wet and dry prces r thre and rotary kiln is the main equipment. grinding,slurry preparation,burning,clinkering,grinding in to powder,packing i think the process to product white cement same with proces production port lan cement. Production white cement in Indonesia may be TIGA RODA Cement

Satyajit Mitra

Adnan Gohar Kiril Angelov Raghu Can Can Somnath Muglikar Jithin Paul Pintu Das Satyajit Mitra

Er Dhaval Patel Ganesh Shendge Jyoti Kate Somnath Muglikar

Jiří Kratochvíla Muzammil Moosavi Nirali Rana Roshan Tembhurne Eng-Sarah Obaid Si Thu Aung Er Dhaval Patel Zé Maurício

can we use electric field or applied voltage to seprate a mixture of chemicals yes we can in elecrostatic precipitator Perhaps if it is a mixture of polar + non-polar molecules? ya we can use for example crude oil and water are repeated by applied voltage We can't separate mix. of chemicals but we can separate solid from solution. Desalter is a vessel used in a petroleum industry used to separate water from crude oil using high voltage electric field yes, In refinery desaltaion is done by that we can seprate potable water from municipal waste water by applying voltage difference,as we can use the polarity and conductivity of water for this. Yes i think...we can seprate the chemical mixture with the help of applied voltage Mayb no...coz its difficult to separate liqud chems as bonding is vry strong... @jiri-It is possible only if the electric potential difference between atoms of the solution have great difference. Electrodialysis Is used to concentrate the solution, not for separation. Electrodialysis or electrodesalination - I have small one with performance 20 000 liters of solution per hour Nops by applied voltage we can only separates the particular ions, not a mixtures or compounds, May be yes we cn use May be ion exchange

any one here can tell me the ways for phenol analysis in solution , and how to know the conc. of phenol in any solution use propylene glycol solution Gas chromatography gas chromatography www.scielo.br/pdf/jbpml/v47n4/v47n4a07.pdf

Eng-Sarah Obaid

Rashad Ahmed

Shantanu Lanke Rashad Ahmed Jeevarathnam Joseph

Nauman Rajpoot Yeong Leong Lim Er Dhaval Patel Marwa Alazzawi Laurence Silvester

i searched about Gas-Chromophotometer device , but i found it analyzes gases only my problem is phenol in petrochemical wastewater discharge i want to know the conc. of it in the wastewater or any other solution Have a look to this link . it could help http://www.ncbi.nlm.nih.gov/pubmed/12373400 it is about "Determination of total phenols in environmental wastewater by flow-injection analysis with a biamperometric detector" u can use bromine water to estimate it HPLC could NOT be useful due to the sensitivity of the device while we are dealing here with wastewater discharge which is contaminated enough Simply..u can buy a phenol checker tablet....take 20 ml water sample contains phenol..put one tablet ..shake well until tablet dissolved...if no phenol...the colour will pale yellow..if colour is pale pink...less than 5 ppm...if colour is dark pink..more than 5 ppm..... Use perkin elmer gas chromatography clarus 58 hi u can try gc-ms where the solvent is organic based (eg. hexane) Hplc U can use HPLC , GC , UV sorry no mass spectrometer, just gas chromatography with flame ionisation detector

Er Dhaval Patel Jeevarathnam Joseph Jovan Karadzic Mehrdad Ben Amr Waly Carlos Angeles Bardellini Camilo Diaz

What type of insulating materyal is used to absorbe radation coming from radioactive material Lead... Lead. Or you can make wall with combination of dirt and concrete, but that's a large scale project 5 cm lead mostly but the thickness depends on, where u wanna use it!! Lead Radiation* Lead Lead

Satyajit Mitra Awadhesh Pandey Kiril Angelov Er Dhaval Patel Suraj Chaudhari Dileep Prajapati Omer Bin Sohail Awadhesh Pandey Dileep Prajapati Chintan Patel 孫殿元

is dehydrogenation of organic compound possible by electrolysis. Need to have right temperature and catalyst in reactor and it can not be done by electrolysis. Don't think so.. Heating + catalysts is the method. No because electrolysis seperate organic compound No... If u try ur process then ur material will catch the fire and you will be responsible for that. No My question is "co-catalysts are used to promote catalyst.....what we can call agents that enhance activity of co-catalysts" Co-Catalyst Promoter Promoter activater but it is not approachable in many cases promoter promoter

Dileep Prajapati Fabio Carrera Fouad Salih Ritwick Das Arturo Sedano

Debananda Sahoo Mohammed Salih Abhinav Kumar Labhishetty Mohamed Eldars Sartaj Rather Rohit Gupta Jignesh Shah Er Dhaval Patel Ronald Allan Co

write a name of thermodynamic property which is same for all substances at absolute temperature? Entropy absolute temperature itself according 3rd law entropy.,. Entropy is valid only at perfect cristaline structure at zero degrees, for quasycristals or structures more complex it doesn't apply, i guess, is temperature itself. Entropy entorpy entropy i think entropy entropy ENTROPY Entropy Specific volume absolute entropy, 3rd law of thermodynamics

Eng AmrMostafa

If we have 2 component A and B. A has a 90 c BP and B has a 88 BP haw to separate them by distillation? Shakir Javed may be by azeotropic distillation Emad El Gebesy Think out the box,if the relative permiability high, then use memberane. However you might have another solutions than the distillation ‫إسراء عبد المعز‬ distillation can't be useful in this case because the 2 components have temperatures close to each other,, to use distillation, temperatures must be greatly different. to know how to separate them we must first know the type of these components ( liquid or solids) but from these boiling points they Seem to be liquid so we can separate them by any method other than distillation such as: (Solvent Extraction-Adsorption- Membrane). Krunal Shah It depends on their equilibrium conditions...if they are not making azeotropes then YES...in the refinery I was working there was a column called C3-C3 splitter which was used to separate Propane and Propene...you can see the difference of boiling point of them is very less but It is possible...the column was 110m tall coz it required higher...much more number of stages...! Aafaq Ur Rehman Azeotropic Distillation is the best solution to separate them.....! Arslan Akram Abhinav Kumar Labhishetty

Nirali Rana

Ashok Kumar Chandra Ashok Kumar Pintu Das Ritwick Das

yup by azeotropic distillation mass separating agents are used to separate close boiling mixtures. these processes are called by two names; 1) Azeotropic --when the agent is volatile, and 2) Extractive --- when the agent is non volatile By using any proper chemical as solvent or extraction n perform azeotropic or extractive distillation as per feasiable operating conditions... azeotropic distillation is the best method to seperate these two component. either by azeotropic or extractive distilation which depends on the third component added Distillation can be made with high distilation ratio witha long column . if still desired level of separetion not achive we can go for extractive distilation azeotropic distillation

Eng AmrMostafa Mohsin Raza Ankit Garg Muhammad Uzair Nawaz Yeong Leong Lim Debananda Sahoo

Raghu Can Can Dharmaraj Nagarajan Shoaib Yasir Mohammed Salih Mekebib Tadesse

Er Nidhi Jethva Eman Abdullah Ibrahim Er Dhaval Patel Chor Beng Nirali Rana

Sirajuddin Mohammad

If we have 2 component A and B. A has a 90 c BP and B has a 88 BP haw to separate them by distillation? extraction by adding solvent or third component .....or adding such a substances which is soluble in either any one " by pressure distillation column azeotropc distilation using third solvent and undergo liquid-liquid extraction.. and continue for distillation.. If by adding solvent we can vary their boiling point then we should follow fractional distillation. Instead azeotropic distillation should be followed. I have come across with cryogenic distillation where argon and oxygen have boiling point near to it. there we use two fractional distillation column name crude argon and pure argon column where we separate argon to a purity of 99.9999 %. I think he we maintain maximum reflex ratio we can separate azeotropy distillation

vaccum distillation azeotropic distillation we can that is let we put impurification on that of the compound that hinder the boiling point of the other let than or faster than that of the other then deal with the separtation enjoy with chemistry Azeotropic distillation first use extraction by suitable solvent , then distillation By azeotropic or differentiyal distillation maybe extractive distillation If saparation is taken out by distillation,der r num of ways to get high purity of product as increas num of tray,set proper refulx ratio,feed location n many... First have to check its relative volatility at the working temperature if it is close to one then distillation becomes cost effective...

Eng AmrMostafa Ram Harsha Sri Chemical Rams Nidhi Sharma Er Mayur Patil Ronald Allan Co Abdelrahman Mohamed Khalid Rita Youfa Rita Youfa Zé Maurício

Satheesh Kuppusamy Rohit Gupta Er Dhaval Patel Kiril Angelov

Raghu Can Can Syed Shah Jehan Gillani Muhammad Waqar Dileep Prajapati Ragunathan Jayaraman Zé Maurício

If we have 2 component A and B. A has a 90 c BP and B has a 88 BP haw to separate them by distillation? By adding a azeotrp Yes....afkos azetropic distillation By azeotropic distillation by adding high boiling point entrainer.....like a Extractive or Azeotropic distillation first, make a VLE table. from that you can evaluate if the components can be separated by distillation through finding its efficiency. i think there's a great difference between azeotropic mixture and miture of 2 liq have close boiling point you can read liquid-liquid extraction to compare with azeotropic distilation i think you can use azeotropic distilation Perhaps the vacuum distillation for help. Let's see the diagram Bp vs P. What is the lab analysis made for finding out formaldehyde and methanol in a solution? GC ANALYSIS Gas chromatography For formaldehyde, silver (I) oxide in ammonia solution, e.g. [Ag(NH3)2]OH, the formaldehyde is oxidized to formic acid and silver is precipitated on the walls of the vessel.

for corrosive fluids we use diaphragm value but for errosive fluids which type of value used? double seated valve or valave with low pressure drop.. i think pinch valve Sweep angle design reduces fluid impingement through the body to offer high resistance to erosion damag Sweep angle design with proper selection of control valve body and trim materials will help in erosion-related damage... ya pinch value

Deep Bhattacharjee Krunal Shah Nafees Ahmad Pintu Das Fawad Malik Er Dhaval Patel Hasan Salamah Jyoti Kate Shivaraj BK Salahuddin Rajput Raditya Caesaryanto Kiril Angelov

Deep Bhattacharjee

Jeet Sarkar Roua Omer Siddiq Piyush Jadav Eng.M Abdelrazek Swapnil Palandurkar

how separate hexane + water when hexane is a bottom product and water is top product in a column or dehydrator...? come on....haxane boils at around 60-65C and water at 100C...how can you get water as top...?????????? Depends on quantity of water present in hexane, if it is more distillation is best option and if water is lesser molecular sieve drier can use. go for crystalisation. the two componets is haveing huge freezing pt difference. hexane is more volatile than water..so taking products at these places is quiet bad idea. Distillation simple distillation V cn separte it by using distillation cloum..easiest technic.. simple distillation s better way...I think so... column dehydrator Column is the easiest way, I believe, just drain the fluid until there's only water in the column. Boiling could also do, hexane boils at around 70 deg C, not sure about the isomers, but still, lower temp than water. It will boil off first and can be collected in gaseous state above the mixture. Column is still the better solution, IMO. There is a dehydrator/column have a thermosyphone reboiler facility, to separate this mixture(C6H14+H2O) in HDPE(Mitsui Tech.) production plant where hexane use as a solvent. The condition maintain is 75-80 C and 0.4 Kg pressure. But my question what the logic behind it? Distillation i want process description about production chloroethylene (VCM) the raw material is Ethylene and Clorine http://nptel.iitm.ac.in/courses/103103029/16 How to use rate equation in HYSYS ? http://www.owlnet.rice.edu/~ceng403/hysys/reactions.html

Nagesh Marwadkar Ahmed Mohamed Khalil

Prashant Shah

Aban Dhani Hsse Nirali Rana

Pintu Das Sana Ullah Ronald Allan Co

Raghu Can Can Shantanu Lanke Usman Naseem Mazhar Abbas Shivaraj BK Sachin Chavare Dileep Prajapati Muhammad Waqar Radhakrushna Sahu Ronald Allan Co

Is pressure drop calculation is same for LIQUID & GASES.If no tell me reason. i think it differs, for incompressible fluids we can use Darcy equation for compressible fluids we can use Panhandle Equation. No... Liquid has to be considered under incompressible fluid... N gas has to be compressible so eqn had been change for both.... Different characteristic of properties.. each have different coefficent No only for ideal gas n liq same calculation cn be apply bt for nonideality some physical properties n many nums changed..sm calculation cnt apply compressbility factor need to be consider. different density, viscosity, and expansion factor for reality of properties of gases, you may refer the thermodynamic properties of gases for both saturated vapor and saturated liquid states. can we recycle expired chemicals like acids bases etc., they expire due to their reduced activity with time Acid and bases do not expire in reality... acid n base never expired,yet their rectivety decreases. ya... u can.. but that wil be complex.. Yes you can...but before recycling you need to analyse those chemicals n if required you have to process it to make it usable.. It is most complex & not for all chemcls not at all no They can be recycled, but they must first analyze their purity. They can be reprocessed.

Muhammad Waqar

is reflux ratio responsible for product purity or impurity in the process of distillation column?

Shantanu Lanke Syed Shah Jehan Gillani Jorge Enciso Acuña

yes yes Yes... as reflux ratio increases, degree separation increases

Arthur Shih

Yup! Also, energy requirements will increase and total product flow rate will decrease. then it means we can increase reflux ratio to a optimum value to keep our energy requirments at proper value... yup absolutely right optimum reflux ratio will maintain the product purity in desire concentration and also the energy requirement for reboiler and condenser will also proper. For getting optimum reflux We have to optimize between operating cost n fixed cost via modeling through softwares. yes yes purity Ofcourse..purity is relet wid it to optimize your reflux you have to define the minimum reflux requiered for the separation and then you can use this:1,2 Rmin
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