An Internship report on fertilizer industry in pakistan...
INTERNSHIP REPORT
Pak American Fertilizer Limited Iskanderabad
Presented By Muhammad Khuram Zahid Mahmood Aqeel Abbas Nouman Asad Arshad Naveed Roman Bin Tariq
(M08-CE-47) (M08-CE-06) (M08-PG-01) (E08-CE-40) (E08-CE-40) (E08-PG-19)
Department of Chemical Engineering and Technology
UNIVERSITY OF THE PUNJAB
Downloaded From : http://www.ICETStudentS.com
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
|2
ACKNOWLEDGEMENT First of all, I would like to say Alhamdulillah, for giving me the strength and health to do this internship work until it done We offer our heartily respects to the HOLY PROPHET HAZRAT MUHAMMAD (SAW) who is, forever a torch of guidance and knowledge for humankind as a whole. Not forgotten to our families for providing everything, that is related to this internship work and their advice, which is the most needed for this journey. They also supported us and encouraged us to complete this task so that I will not procrastinate in doing it. We’d like to thanks our respected teachers for their moral support, their guidance in time, useful suggestions and their confidence on us that we can do this task efficiently as we are representing our Institute. It’s not very easy for us to find the right words to express my gratefulness to our advisor Mr. ABDUL HASEEB, his enthusiastic interest, continuous encouragement, and kind behavior throughout my internship period. Apart from our respectable advisor, there are many other people who have been very helpful to me right from the beginning. We would warmly acknowledge the entire management of Pak-American Fertilizer Limited who provided us this opportunity to achieve this practical experience under their valuable supervision and helping suggestions to complete this report. Last but not least, my friends internship colleagues who were doing this project with me and sharing our ideas. They were helpful that when we combined and discussed together, we had this task done.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
|3
EXECUTIVE SUMMARY This report is based on our four weeks EXPERIENCE at PAK-AMERICAN FERTILIZER LIMITED as an internee from 1st June to 29th June. THE COMPANY IS a highly reputed organization. PAFL is one of the pioneers of the fertilizer industry in Pakistan. It owns and operates urea plant located at Daudkhel, Iskanderabad District Mianwali. The salient features of this report are: Pak-American Fertilizer Limited background, its vision, corporate values and goals. This report focuses its overall marketing strategies, its production and operations, and its Human Resource. The process description of the firm has been done in detail. The flue gas Analysis, water treatment plant Analysis are really a fascinating experience of mine. This report accentuates the details of my learning and observation at PAFL. It also includes the actual techniques that are used in this organization to carry out basic processes. And we were sure that this report will provide you a complete and clear image of organization.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
|4
CONTENTS_________________________ HISTORY ................................................................................................6 AMMONIA SECTION............................................................................7 UREA SECTION.....................................................................................27 UTILITIES SECTION............................................................................34
ICET Students
Digitally signed by ICET Students DN: cn=ICET Students, o=ICET Students, ou=Administrator,
[email protected], c=PK Date: 2011.06.11 12:27:19 +05'00'
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
|5
HISTORY The Plant is located at Iskanderabad, District Mianwali. It was the first nitrogenous Plant built in Pakistan. The project when commissioned in 1957 was designed to produce 40 metric tones per day of Ammonia to be fully converted into 150 metric tones per day of Ammonium Sulphate. The unit underwent expansion in 1968 when the capacity was increased to 273 metric tones per day i.e. 90,000 metric tones per annum of Ammonium Sulphate. The Ammonium Sulphate Plant was closed in June, 1997 and a new Ammonia /Urea Complex having capacity of 600 metric tone per day of Ammonia and 1050 metric tone per day of Urea, started commenced production in November, 1999. The annual production capacity of the Plant is 346,500 metric tone of urea. Total completion cost of the Project was Rs.9, 700.060 million, out of which Rs.6, 878.119 million was in foreign currency. The authorized and paid up capital of the Company is Rs.3, 000 million, which is subscribed by NFC. The raw material used is Natural Gas from SNGPL Network. Today the plant is running at 1176 tone per day which is the 112% of the designed capacity 1050 tone per day of Urea and 650 tones per day of Ammonia. Both plants have been designed by TOYO Engineering Japan. Ammonia plant is under license from Kellogg International, USA, while urea plant is TEC's own. The plants are latest in design and most modern. The company possesses over 11,481 Kanals of land, comprising 6,432 for Factory, 2,818 for Housing Colony and 2,230 for experimental farm.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
|6
Ammonia Section
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
|7
GENERAL OVERVIEW Ammonia is produced in a process in which nitrogen and hydrogen react in the presence of an iron catalyst to form ammonia. The hydrogen is formed by reacting natural gas and steam at high temperatures and the nitrogen is supplied from the air1. Other gases (such as water and carbon dioxide) are removed from the gas stream and the nitrogen and hydrogen passed over an iron catalyst at high temperature and pressure to form the ammonia. The process is shown schematically in Figure 1. The ammonia process is the low energy natural gas reforming process. Offered and licensed by the M.W kellog company. The ammonia plant design is based on producing 6oomtd of anhydrous liquid ammonia. Under normal operating conditions liquid ammonia is delivered to battery limits at 30 0c. for uses feed to urea plant in the event that the urea plant is not working the ammonia product can be delivered to the battery limits -33 0c. for offsite storage. By product CO2 is delivered to the battery limits at 38 0c and 1.9 kg/cm2.
FEED STOCK SPECIFICATIONS:
Component gas
Mole %
CH4
82.6
C2H6
8.5
C3H8
3.3
C4+ higher
1.9
CO2
1.3
N2
2.4
TOTAL
100%
Pressure at battery limits: Temp at battery limits: Lower heating value (LHV)
7.5 kg/cm2 28 0c 9609 K cal/nm3
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
|8
The process is described in the following sections: Raw synthesis gas preparation: Synthesis gas purification: Purified synthesis gas compression and ammonia synthesis: Ammonia refrigeration system: Process condensate stripper: Steam system: Other utilities:
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
|9
RAW SYNTHESIS GAS PREPARATION The raw synthesis gas is produced from natural gas is produced from N.G in four major steps.
Compression.
Partial reforming.
Final reforming.
Conversion of carbon mono oxide and steam in the reformed gas.
N.G is used for feed stock and fuel. The N.G at 7.5 kg/cm2 passes through the feed gas knock out drum to remove suspended liquids and solids. The N.G is split up in to two streams feed gas and fuel. The fuel gas portion is combined with recovered gas from synthesis to provide the ammonia plant net firing requirements. The feed gas portion is compressed to 46 kg/cm2 in a steam turbine driven two stage centrifugal natural as compressor. A N.G pressure gas cooler and n N.G knock out drum are provided in order to provide 2 % hydrogen level in the natural gas stream. A recycle stream of hydrogen rich synthesis gas from 104 j pump is added to the second stage suction and a start up hydrogen rich stream from A-103 –F pump can be added to the first conditions. A-135-c is also utilized for spill back from operation which allows all or part of the discharge gas to be recycled back to the a-102-j first discharge line.
DESULFURIZATION The sulphur compounds contained in small amounts in the feed gas are removed by catalytic reaction with the hydrogen in the gas over a Como catalyst followed by absorption with ZnO. The compressed natural gas is heated to 399 0c. in the convection section of the primary reformer A-101-B. The natural gas and hydrogen combined streams then flow down through the hydrotreator. A-101-D hydrogenating the organic sulfur compounds to H2S over a bed of Como catalyst. The reacted gas then flows through the desulfurizers A-102-DA/B where zone absorbs the INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 10
H2S producing an effluent stream containing less then 0.1 ppm by volume of hydrogen sulfide.
PRIMARY REFORMING The 3880C desulfrized gas is mixed with 44 kg/cm2 and 3900C high pressure steams, a part of which was used to strip the process condensate before hand. The steam is added in a ratio of 3.5 moles of steam per mole of organic carbon. The feed gas/steam mixture is then preheated to 621 0c in the convection of the primary reformer, A-101-B, recovering heat from the furnace flue gas. After pre heating, the mixture is distributed to the catalyst tubes suspended in the radiant section of the primary reformer furnace and passes down through the nickel reforming catalyst. The heat from the endothermic reforming reaction is supplied by fuel gas burner’s located b/w the row of the tubes. The pressure at the outlet of the catalyst tubes is 37.2 kg/cm2 . The reforming furnace incorporates the use of internal man folding at the outlet of the catalyst section for heat conversion of the reformed gas. The reformed gas continues to pick up the heat in these risers and collector headers while exciting the radiant section. This raises the gas temp aprox to 8330C. The reforming furnace is designed to attain maximum thermal efficiency by recovering heat in the convection section from the flue gases. Flue gases consist of combustion products from the radiant section of the reformer and the auxiliary boiler. The convection heat is used for the following services.
Process air.
Steam
Natural gas feed preheat for desulphurization.
Steam super heating.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 11
Reformer fuel preheats.
Combustion air preheats for the reformer burners.
The super heat burners in the compression section and the boiler together with the reformed gas waste heat boiler, A-101-C and the high pressure steam super heater will maintain the plant in steam balance and generate export stream for the urea and utility plants.
CH4 + H2O → 3H2 + CO CH4 + 2H2O → 4H2 + CO2 CO + H2O → H2 + CO2
SECONDARY REFORMING The reformed gas flows from the outlet of the primary reformer through the primary reformer effluent transfer line A-107-D to the secondary reformer A-103-D there it is mixed with the quantity of heat and air to provide the N2 requirements of ammonia synthesis reaction the heat librated by combustion of the part of partially reformed gas supplies the energy needed to complete the reforming action the reformed gas temp leaving the secondary reformer is about 1013 0C.
CO + H2O → CO2 + H2 O2 + 2CH4 → 2CO + 4H2 O2 + CH4 → CO2 + 2H2 2O2 + CH4 → 2H2O + CO2 The secondary reformer effluents passes directly to the reformed gas waste heat boiler where SHP steam is generated by by hot gasses passing through the tube side. The partially
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 12
cooled gas then passes through the SHP super heater A-102-C and cooled to high temp shift inlet temp. of 3710C this super heater provides part of steam super heat requirements with the remaining portion fulfilled by coils in the reformer convection section a process by pass is provided b/w these two exchangers to various steam balance requirements.
SHIFT CONVERTERS Down stream of A-102-C are high temp, and low temp. Shift converters. A-104-DA and A104-DB, in shift conversion step, CO reacts with steam to form equivalent amount of H2 and CO the shift reaction is reversible and exothermic. The reaction rate id favored by high temp and maximal conversion by low temp. Two stages of shift conversion are provided with HP boiler feed water heating between them to moderate heating the gas temp.
CO + H2O → CO2 + H2 CO + 3H2 → CH4 + H2O CO2 + 4H2 → CH4 + 2H2O The heat from the HTS A-104-DA is recovered by heating high pressure boiler feed water in the shell sides in series of HTS effluents BFW preheaters, A-103-C1 and A-103-C2. The low temp. shift effluents provides energy for CO2 removal system with the remaining use full heat utilized to preheat boilers feed water for the plant steam system in LTS effluents /BFW pre heaters located down stream of the benfield exchanger in the A-106-C, Demineralized water is pre heated before it is sent to the dearator A-101-U. The benfield system utilizes the LTS effluents waste heat as follows: Steam generation in the CO2 stripper over head condensate reboiler A-113-C, Benfiled system sol. Reboilng in the CO2 stripper gas reboiler A-105-C.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 13
The process gas is cooled below its dew point in the process gas exchanger and condensate generated is removed from the gas in the CO2 absorber feed gas separator A-103-F. The raw condensate is pumped to condensate stripper A-103-E to removed dissolve gasses and any shift reaction by products so the water is reused and boiler feed make up after treatment in the offsite polisher. After condensate removal raw synthesis gas at 75 0C and 32.5 kg/cm2 enters the bottom of the CO2 absorber A-103-E in the benfield system to begin the purification setup.
SYNTHESIS GAS PURIFICATION In this section synthesis gas is proceed to remove CO2 and CO, yielding a high purity H2 and N2. Bulk removal of carbon dioxide is accomplished by the use of an improved benfield low heat process which uses the four stage flash of the semi lean sol. to minimize external heat requirements. Final removal of residual CO2 and CO. is accomplished by catalytically converting the CO2 to methane and water in the methenator using hydrogen. The benfield “low heat” process circulates an aqueous sol. containing a nominal 30% potassium carbonate This potassium carbonate chemically combines with CO2 on the process gas but not significantly with the other constituents. Additives are injected into the solvent to enhance the CO2 absorption rate, inhibit corrosion and to control foaming.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 14
ABSORPTION OF CO2 In the packed absorber A-101-E, removal of CO2 from the synthesis gas is carried out in two absorption stages by counter currently contacting the gas with the benfield sol. raw synthesis gas enters the lower Section of the absorber where the major portion of CO2 in the gas is removed by contact with partially regenerated “semi lean” sol. In the upper section of the absorber the process gas leaving the lower section is contacted again but with more thoroughly regenerated “lean” sol. resulting in an exit gas CO2 level of 1000ppmv. In the upper section of stripper the “rich” benfield sol. Is the partially stripped of CO2 . A major portion of the sol. Is then with drawn and fed to A-117-F. The exiting semi lean sol. is returned to the lower section of the absorber via the semi lean sol. Circulation pumps. A-107-J, JA. The reminder of the partially regenerated sol. is further regenerated in the stripper lower section, where most of the remaining CO2 is removed from the solvent. The resulting “lean” sol. is with drawn from the bottom of the stripper cooled to 70 0C. by preheating de aerator feed water in the lean sol. /BFW preheater, A 107 C and by cooling in the lean solution cooler A-108 –C and then pumped by the lean solution circulation pump A-108J,JA to the top of the absorber.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 15
STRIPPER The stripper is operated at conditions of 128 0C and 2.1kg/cm2 at the bottom of the column. Heat required for stripping, available from low temp. Shift effluent, is obtained by reboilng, benfield sol. In A-105-C by reboilng reflux condensate in A-113-C, flash cooling of the semi lean in A-117-F lowers the required heat input to the stripper and enables the process to operate with out need of sources except during start up. This system maximizes reboiler heat recovery from the low temp. Shift conversion effluents by taking advantage of the lower boiling point of the condensate compared to carbonate sol. Blow down from A113-C is required to the system by injection in to the lean sol flow through A-105-C. After separation from the benfield sol. The CO2 product vapor is cooled to 38 0C, by direct contact cooling with quench or reflux water in a packed bed above the benfield stripping section of the tower quench water is circulated by the CO2 stripper quench pump. To the CO2 stripper quench cooler. In this exchanger the quench water is heat is rejected to the cooling water, water condensed from the CO2 product vapor during cooling is removed from the cooling circuit to satisfy the water make up requirements. After being cooled the 99% CO2 product passes through the demising pad, exists the tower and is exported for use in urea. The absorber over head gas containing approx 1000ppmv CO2, is designed of an entrained liquid in the CO2 absorber over head knock out drum A-103-F, and preheated to about 326 0
C by the methenator effluent in the methenator feed exchanger A-190-C a by pass is
provided around the exchanger to control the inlet temp. A line is provided from A-103-F exit to the suction of A-102-J to provide H2 for start up and low temp shift reduction.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 16
METHANATOR The metahntorA-106-D contains a bed of nickel catalyst that promotes the reaction of CO2 and CO with H2 to form methane and water. The total carbon oxides leaving the methanator. Will be less than 5 ppm by vol. due to highly exothermic nature of the methanation reactions the synthesis gas temp increase from 316 at the inlet to about 347 0C at the out let. The heat energy in the methanator efffulent is recovered by the heat exchange against the feed gas the purified synthesis gas is then cooled to 41 0C on the methanator effluent cooler A-115-c and delivered to the synthesis gas compressor suction drum A-104-F to separate condensate water a small flow is taken from A-104-F exit to the second stage suction of A-102-J to provide the H2 for desulprization.
SYNTHESIS GAS COMPRESSION AND AMMONIA SYNTHESIS The synthesis gas is compressed in a turbine driven centrifugal synthesis gas compressor A103-J.the compressor consists of two casings with inter cooling , condensate removal and molecular sieve purification b/w cases and a integral recycle wheel in the second case, after compression in the first case to approximately 78.06 kg/cm2 the synthesis gas is cooled to 41 0c in the syn gas compressor interstage cooler A-1116-C,and then cooled to 4.4 0c with ammonia refrigeration in the syn gas compressor inter stage chiller A-129-C,condenste is separated from the synthesis make up gas in the syn gas compressor first stage separator, A-105-F.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 17
MOLECULER SEIVES following the condensate removal , the synthesis gas passes, through one of the two molecular sieve driers A-109-DA/DB the driers use molecular sieve absorbents which remove water and trace amounts of CO2 to less than 1ppm by vol. while one molecular sieve unit is in use the other is being regenerated on an 8-12 hour cycle or on stand by. Dried gas exit the on line drier is used to regenerate the molecular sieve vessel not in service during regeneration of the molecular sieves, the dry synthesis gas is first heated by super high pressure steam in the molecular sieve regeneration heater, A-173-C, after passing upward through the molecular sieve bed the refrigeration gas is recycled to the methenator feed. The purified synthesis gas leaving the molecular sieve unit is further compressed in the make up gas section of the high pressure compressor case the fresh synthesis gas is mixed with recycle gas from the synthesis lope internally with the compressor case before entering the recycle wheel. Of the compressor, the combined flow to the synthesis lope leaves the compressor at about 146 kg/cm2. A syn gas kick back cooler A-175-C, is provided to protect the compressor over a vide range of operating conditions. A A-103-J, discharge seal oil separator, A-111-L, is provide at he compressor discharge to trap only oil from the compressor during an upset.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 18
AMMONIA REACTOR Before going directly to the ammonia reactor synthesis gas leaving A-111-L, is preheated in the ammonia converter feed exchanger , A-121-C, to 253 0c and sent directly to the converter provisions has been made for by pass of the exchanger to control the temp. of the converter feed.
N2 + 3H2 → 2NH3 The horizontal ammonia synthesis converter consists of a pressure shell, a removable catalyst basket, and a ammonia converter interchangers. The converter contains 31.6m3 of synthesis catalyst divided into three thermodynamics beds and four physical beds, each supported on profile wire screens. The catalyst beds are arranged so that the first bed is the smallest to limit the temperature rise. The feed gas to the converter is split into two streams. The first feed split stream passes through an annular space between the shell and converter basket. This helps to cool the shell and keeps the converter basket at a uniform temperature. This feed gas stream receives some preheat prior to interchanger – tube side where it is preheated to the desired first bed temperature. The second feed split stream is heated in the second interchanger – tube side before mixing with the first preheated split feed stream. The preheated total converter feed stream passes down through the first catalyst bed where over 50% of the total ammonia conversion occurs. The first bed effluent is cooled by passing through first interchanger – shell side and flows to the second bed. The cooled first bed effluent passes down through the second catalyst bed where more ammonia conversion and temperature rise take place. The effluent from the second bed is cooled passing through the shell side of the second interchanger before flowing down over the third beds. The third catalyst bed is divided into two physical beds in series flow configuration. This is to ensure uniform flow over the catalyst. Further reaction in the third catalyst beds raises the converter outlet temperature to about 454 0C and the ammonia concentration to 15.8 mol %.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 19
The design feature of an intercooler horizontal ammonia converter has the advantage of producing a relatively high ammonia concentration per pass and making the heat available in the converter effluent at a sufficiently high temperature for high pressure steam generation. The horizontal arrangement of the converter produces a lower pressure drop through the catalyst beds then a vertical, axial-flow type and enables removal of the basket and interchanger by using a diameter that is within the fabricating limitations of full closure. The heat of reaction from the ammonia synthesis is recovered from gas leaving the converter by cooling it to 278 0C in the ammonia converter effluent BFW preheaters.
The cooled converter effluent is further condensed in the ammonia converter effluent recycle exchanger. This specially designed chilled further provides for cooling of the converter effluent through interchange of the heat with ammonia vapors returning from the ammonia product separator and boiling ammonia liquid at four different temperature levels ( 20.6 0C, 0 0C, -17.9 0C, -33.3 0C). This unitized chiller consists of multiple co centric tubes which run through the boiling ammonia compartments. Synthesis gas recycle vapors pass counter currently through the center tube and the converter effluent flows through the annular tube. Thus, the converter effluent is being cooled from the outside by ammonia refrigeration and from the inside by vapor from the ammonia separator. The converter effluent is condensed at -17.8 0C in the
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 20
unitized chiller and the liquid product disengaged immediately downstream in the ammonia product separator. Recycle vapor from the ammonia separator, containing near 2.79 vol% ammonia, is reheated in the unitized chiller as described above. After leaving the exchanger, a small portion of the gas is split off to the ammonia absorber, to prevent inert gas accumulation in the loop and recover the remaining ammonia in the purge gas. The remainder of the recycle vapor is directed to the synthesis gas compressor, mixed with fresh synthesis loop feed, and compressed for reuse as feed to the converter. Liquid from the ammonia separator is flashed into the ammonia letdown drum. The flashed vapor, primarily inert, is mixed with the refrigeration system purge gas and sent to the ammonia absorber. The liquid ammonia product is then split into several streams leading to the refrigeration system and to the purge gas cooler section of the refrigerant receiver.
AMMONIA REFRIGERATION SYSTEM A four stage ammonia refrigeration system provides refrigeration for ammonia condensation in the synthesis loop, recovery of ammonia from vented gas, and synthesis gas compressor make-up gas chilling. The four refrigeration levels operate at approximately 20.6 0C, 0 0C, -17.9 0Cand -33.3 0C. The refrigeration system consists of a two-case centrifugal compressor with two intercoolers, a refrigerant condenser, a refrigerant receiver, evaporator and a four stage flash drum which forms an integral part of the unitized exchanger. Provision is made for contact chilling and venting of any inert gases dissolved in the warm liquid ammonia product. Additional provision is made to recover a small amount of ammonia vented from atmospheric storage to the first stage suction of the refrigeration compressor. Ammonia vapor from the second case of the ammonia refrigerant compressor is cooled, condensed at 38.2 0C in the refrigerant condenser and then sent to the refrigerant receiver.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 21
Inert and uncondensed ammonia vapor from the refrigerant receiver and the refrigerant condenser enter the contact chiller section on the top of the receiver where it is washed with cold ammonia from the ammonia letdown drum condensing the ammonia to drain back to the vessel. The inert gases containing ammonia vapor from---along with the flash gases from ---- are sent to the ammonia absorber. A major portion of the liquid ammonia from the refrigerant receiver after mixing with a small amount of the cold ammonia from the letdown drum leaves as warm ammonia product from the plant. It is pumped by the hot ammonia product pump to the urea plant. The remaining liquid is flashed into the fourth stage refrigerant flash drum at 20.6 0C and 8.9 kg/cm2a. Liquid in the fourth stage drum provides refrigeration to the fourth stage chiller section of the unitized exchanger. Liquid from the fourth stage drum is flashed by letdown into the third stage refrigerant flash drum at 00C and 4.4 kg/cm2. a portion of the liquid from the fourth stage refrigerant flash drum is routed to the synthesis gas compressor interstage chiller with the vapors delivered to the third stage flash drum. Liquid in the third stage drum provides refrigeration directly to the third stage chiller section of the unitized exchanger. Liquid from the third stage drum is flashed into the second stage refrigerant flash drum at -17.9 0C and 2.1 kg/cm2a. liquid in the second stage drum provides refrigeration directly to the second stage chiller section of the unitized exchanger. The net liquid from the second stage drum is flashed into the first stage refrigerant flash drum at -33.3 0C and 1.0kg/cm2a. Liquid in the first stage drum provides refrigeration directly to the first stage chiller section of the unitized exchanger and can also be sent to the atmospheric storage tank via the cold ammonia transfer pump. The vapor generated in the four refrigeration drums are fed to the appropriate stage of the two case, steam turbine driven centrifugal ammonia refrigerant compressor. The heat of the compression is rejected to the refrigerant compressor 2nd stage intercooler and to the refrigerant compressor 3rd stage intercooler. The vapors are compressed, condensed, and returned to the refrigerant receiver, thus completing the refrigerant cycle.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 22
PROCESS CONDENSATE STRIPPER Process condensate from the carbon dioxide absorber feed gas separator is recovered and reused in the ammonia plant after treatment. Process condensate can contain up to 1000 ppm (by weight) ammonia, 3000 ppm (by weight) carbon dioxide, and 1000 ppm (by weight) methanol and higher alcohols. Before its reuse, the condensate is stripped by steam in the process condensate stripper to reduce the ammonia content to about 10 ppm (by weight) , carbon dioxide content to less than 10 ppm (by weight) , and the combined methanol and higher alcohol content to approximately 25 ppm (by weight) . The stripped condensate may also contain up to 2.5 ppm (by weight) of metals. The treatment of the process condensate is carried out by steam stripping in a packed column using a portion of the high pressure process steam. The process condensate is preheated by the stripper effluent in the condensate stripper solution exchanger, and then distributed to the top of stripper packing. The process condensate is stripped by the rising counter current flow of steam. The stripper overhead is mixed with the remaining process steam and combined with the desulphurized process natural gas and enters the primary reformer mixed feed coil. The stripped condensate, after partial cooling in the condensate stripper solution exchanger, is further cooled with cooling water in the stripped condensate effluent cooler at 41 0C before being sent to water treatment plant.
AMMONIA RECOVERY SYSTEM The high pressure purge gas from the synthesis loop along with the flashed gases from A109-f and A-107-F are sent to the ammonia absorber via the purge gas ejector. In the packed tower at 60.7kg/cm2a/ ammonia is absorbed by the water wash. The absorber overhead gas is used as fuel in the primary reformer. The solution leaving the absorber with the ammonia concentration of about is heated about –in the ammonia solution exchanger,—against hot water from the ammonia rectifier,
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 23
– bottoms. The heated aqueous solution enters the ammonia stripping column below the reflux section of packing. Liquid ammonia reflux to the top of the stripper. Column is provided from the refrigeration system via a side stream at the discharge of the hot ammonia product pumps. The ammonia vapor from the top of the column is fed to the refrigerant condenser, -- where it is condensed. Stripping heat is provided by the ammonia rectifier reboiler, which uses high pressure steam. The ammonia solution exchanger cools the rectifier bottoms which contain –(weight) to – and the ammonia solution cooler, –cools the stripper water to -- . a small amount of condensate from –is added to the rectifier as needed to make up for water losses in the absorber overhead. A scrub water pump is used to pump the cooled water to the top of the absorber.
STEAM SYSTEM There are three principle steam system in the ammonia plant. In order to effectively recover heat efficiently from the process, a super high pressure – superheated – steam system is used to drive the major movers in the plant. This super high pressure steam is generated in the auxiliary boiler and in the reformed gas waste heat boiler – and is used to drive the synthesis gas compressor, -- and refrigerant compressor, -- turbines. Boiler feed water for this generation system is pumped by the h. p. blew pump through the boiler feed water heaters, --and – to the steam drum. the super high pressure steam is also used in the mathanator start up heater, and the molecular sieve regeneration heater and is let down as well to the high pressure header when any of the above turbines is down. The high pressure header at 44.0kg/cm2a, 390 0C is the principle distribution system in the plant. It is supplied by the extraction steam from A-103-JT AND A-105-JT and by letdown when the plant is not in full operation. The motive steam for the air compressor , natural gas compressor, H.P. BFW pumps, condensate pump for A-101-JC, forced draft and induced draft fan, semi lean solution circulation pump, and lube oil and seal oil pump turbines is supplied from this system along with the process steam for the condensate
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 24
stripper and for the primary reformer, and the reformer air coil. High pressure steam is also exported to the urea plant. The low pressure header (4.5kg/cm2a, 282 0C) is the distribution system for the low energy level users in the plant. It is supplied by the exhaust steam from the condensate pump, forced draft and induced fans, the seal oil and lube oil pumps turbines, the seal leak-off steam from A-103-JT and A-105JT, and also the exhaust steam from the steam blow down drum. It supplies part of the motive steam for the air compressor turbine and surface condenser ejectors, and the heating steam for the dearator and various small process users. The surface condenser is used to provide low level exhaust conditions (99 mmHga, 50 0C) for the process major prime movers. The capability of this unit to condense steam at very low energy conditions bears directly on the efficiency and economic success of the plant. This condenser receives vapor from the exhaust of the synthesis gas compressor, air compressor, natural gas compressor, and the H.P. BFW turbines and also from the urea plant. The collected condensate is pumped out of the condenser by the condensate pump(s) send to the secondary reformer water jackets and to water treating for reuse in the plant.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 25
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 26
Urea Section
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 27
GENERAL OVERVIEW Urea [CO (NH2)2], also known as carbamide or carbonyl diamide, is marketed as a solution or in solid form. Most urea solution produced is used in fertilizer mixtures, with a small amount going to animal feed supplements. Most solids are produced as prills or granules, for use as fertilizer or protein supplement in animal feed, and in plastics manufacturing. Five U. S. plants produce solid urea in crystalline form. About 7.3 million mega grams (Mg) (8 million tons) of urea were produced in the U. S in 1991. About 85 percent was used in fertilizers (both solid and solution forms), 3 percent in animal feed supplements, and the remaining 12 percent in plastics and other uses.
UREA MANUFACTURING PROCESS The process for manufacturing urea involves a combination of up to 6 major unit operations. Urea plant is generally divided into following sections. 1- Compressor 2- Synthesis Section & high pressure recovery. 3- Purification & Recovery Section. 4- Concentration Section. 5- Prilling Section. 6- Waste Water Treatment Section.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 28
PROCESS DESCRIPTION SYNTHESIS SECTION & HIGH PRESSURE RECOVERY In the solution synthesis operation, ammonia (NH3) and carbon dioxide (CO2) are reacted to form ammonium carbamate (NH2CO2NH4). Typical operating conditions include temperatures from 180 to200°C (356 to 392°F), pressures from 140 to 250 atmospheres (14,185 to 25,331 kilopascals) NH3:CO2 molar ratios from 3:1 to 4:1, and a retention time of 20 to 30 minutes. The carbamate is then dehydrated to yield 70 to 77 percent aqueous urea solution. These reactions are as follows:
ACES21® process synthesis section consists of a reactor, a stripper and a carbamate condenser. Liquid ammonia is fed to the reactor via the HP Carbamate Ejector which provides the driving force for circulation in the synthesis loop instead of the gravity system of the original ACES. The reactor is operated at an N/C ratio of 3.7, 182 °C and 152 bar. The CO2 conversion to urea is as high as 63% at the exit of the reactor. Urea synthesis solution leaving the reactor is fed
to
the
stripper
where
unconverted
carbamate is thermally decomposed and excess ammonia and CO2 are efficiently separated by CO2 stripping. The stripped off gas from the stripper is fed to the Vertical
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 29
Submerged Carbamate Condenser (VSCC), operated at an N/C ratio of 3.0,180°C and 152 bar.Ammonia and CO2 gas condense to form ammonium carbamate and subsequently urea is formed by dehydration of the carbamate in the shell side. Reaction heat of carbamate formation is recovered to generate 5 bar steam in the tube side. A packed bed is provided at the top of the VSCC to absorb uncondensed ammonia and CO2 gas into a recycle carbamate solution from the MP absorption stage. Inert gas from the top of the packed bed is sent to the MP absorption stage.
PURIFICATION & RECOVERY SECTION The major impurities in the mixture at this stage are water from the urea production reaction and unconsumed reactants (ammonia, carbon dioxide and ammonium carbamate). The unconsumed reactants are removed in three stages3. Firstly, the pressure is reduced from 240 to 17 barg and the solution is heated, which causes the ammonium carbamate to decompose to ammonia and carbon dioxide:
At the same time, some of the ammonia and carbon dioxide flash off. The pressure is then reduced to 2.0 barg and finally to -0.35 barg, with more ammonia and carbon dioxide being lost at each stage. By the time the mixture is at -0.35 barg a solution of urea dissolved in water and free of other impurities remains. At each stage the unconsumed reactants are absorbed into a water solution which is recycled to the secondary reactor. The excess ammonia is purified and used as feedstock to the primary reactor.
CONCENTRATION SECTION 75% of the urea solution is heated under vacuum, which evaporates off some of the water, increasing the urea concentration from 68% w/w to 80% w/w. At this stage some urea crystals also form. The solution is then heated from 80 to 110oC to redissolve these crystals prior to evaporation. In the evaporation stage molten urea INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 30
(99% w/w) is produced at 140oC.The remaining 25% of the 68% w/w urea solution is processed under vacuum at 135oC in a two series evaporator-separator arrangement.
PRILLING SECTION. There are 2 types of prill towers: fluidized bed and non fluidized bed. The major difference is that a separate solid cooling operation may be required to produce agricultural grade prills in a non fluidized bed prill tower. The solids screening operation removes off size product from solid urea. The off size material may be returned to the process in the solid phase or be redissolved in water and returned to the solution concentration process. Urea is sold for fertilizer as 2 - 4 mm diameter granules. These granules are formed by spraying molten urea onto seed granules which are supported on a bed of air. This occurs in a granulator which receives the seed granules at one end and discharges enlarged granules at the other as molten urea is sprayed through nozzles. Dry, cool granules are classified using screens. Oversized granules are crushed and combined with undersized ones for use as seed. All dust and air from the granulator is removed by a fan into a dust scrubber, which removes the urea with a water solution then discharges the air to the atmosphere. The final product is cooled in air, weighed and conveyed to bulk storage ready for sale.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 31
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 32
A Apppprrooxxiim maattee ppeerrcceennttaaggee ooff pprriinncciippaall eelleem meennttss iinn ddiiffffeerreenntt FFeerrttiilliizzeerrss
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 33
Utility section
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 34
GENERAL OVERVIEW Utilities include the following sections
Water intake facility
Water treatment plant
Cooling tower
IGG (Inert gas generation)
G.T(Gas Turbine), HRSG (Heat recovery and steam generation)
Package Boiler
Mitsui Boiler
WATER INTAKE FACILITY For the supply of raw water, PAFL has its own water pumping station near Indus River (Banian Tree site/area.). The Raw water coming from Banian Tree area is used for the following purposes: Make up water for Cooling Tower (old +new).Normal raw water use=3000m3 Potable water at Plants. Potable water at PAFL Housing colony. Water Treatment plant to produce DM water. As cooling water during emergencies. As fire water, 1100m3. Water intake facility comprises on the following:
TUBE WELLS 06 tube wells are in operative condition, designed capacity of these tube wells is 3.0 cusec but due to continuous operation, capacity of old pumps (installed in 1997and before)has dropped to 2.0 ~ 2.5 Cusec. 1. No of Tube Wells in operative condition, installed before 1997 ……….01 2. No of Tube Wells in operative condition, installed in 1997 ………….…03
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 35
3. No of Tube Wells in operative condition, installed in 2004 …………….02 (For these two tube wells, new bores were drilled; one new pump and one old pump were installed)
PIPE LINE 1. 24” ø and 3948 meters length Pipe Line from Banian Tree to PAFL plants. 12” ~ 08 ø and 1500 meters length Pipe Line from PAFL plants to Housing Colony.
RAW WATER ANALYSIS pH
7.5-7.6
M. Alkalinity
120-130 ppm CaCO3
Calcium
112-125 ppm CaCO3
Magnesium
40-50
Total hardness 1
60-170
Chlori de
10-17 ppm
Sulphate
40-50
Silica
12-16
WATER TREATMENT PLANT: For the production of de-mineralized water, required for steam generation PAFL has a water treatment plant of El-Car Company of Italy having 85-tons/hr capacity. This plant comprises on three sand filters and two Ion Exchange Lines, each line comprising on Cationic exchangers, de-gasifier, and Anionic exchangers, mixed bed and Auxiliaries for the regeneration of these Ion exchangers. Operating hours of each line/train are: Cation exchanger/Anion Exchanger = 1020 m3 Mixed Bed
= 168 hrs
Following resins are being used at Water treatment Plant a) Strong Cation resin (for Mixed bed exchanger) b) Strong Anion resin (for Mixed bed exchanger) INTERNSHIP REPORT (Pak American Fertilizer Limited)
Amber jet 1200 Na Amber jet 4200 Cl
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 36
c) Weak Acid Cation resin (for Cationic exchanger)
D 113/ Dilute C 433
d) Strong Acid Cation resin (for Cationic exchanger)
Amber jet 1200 Na
e) Strong base Anion resin (for Anionic exchanger) Amber jet 4200 Na For the regeneration of Cationic resins 98% H2SO4 is used and for the regeneration of Anionic resins 50% NaOH is used.
COOLING TOWER Purpose: Cooling water is used at a plant for condensing steam, for cooling product feed gases, and also for equipment cooling. It is considered, to be“WATER” and the “WET BULB” temperature of the air surrounding it.
Brief Description: PAFL cooling tower is an induced draft type-cooling tower with “Counter Flow” design. The air enter the tower through the louvers at
the
tower base, pulled upward
and
comes in contact with falling droplets of water. In the counter flow towers,
the
drift eliminators are located at the top. The eliminators are placed just ahead the fans to prevent windage losses. These types of towers are specially designed to minimize windage and drift losses which are controlled at 0.005 % and 0.3 % of the water circulation rate. The main component of a cooling water cell is. 1. A frame work i.c. outer structure of a cooling tower cell. 2. A system of fluid distribution and dispersion above the fill (fill: packing). INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 37
3. A film pack fill, which acts as a heat exchanger between the liquid and air. 4. A catchments pond or bay which provides the recooled water to various consumers. 5. A fan which induces the draught. 6. A drift eliminator is to catch the water droplets practically going out with air.
Design Data: Item No.
C-EF-3301 A-F
Service
Cooling Tower
Quantity
One (1) with six cells.
Type
Mechanical draft - Counter flow
Design and Operating Conditions: Circulating water flow
15000 M3 / hr.
Hot (Inlet) water temperature
43 oC
Cold (Outlet) water temperature
33 oC
Wet bulb temperature
30 oC
Tower pump head
9.76 M
Total fan B.H.P
777 KW
Drift losses
0.01 % (of circulated capacity)
Evaporation losses
1.66 % (of circulating
Design wind load
44.4 m / Sec.
Design seismic load Tower site
cap)
0.12 % G. Ground level (Tower will be constructed above ground level).
Elevation above sea level
228.5 m
Tower exposure
Open
Structural Details: Number of cells
Six (6)
Fan per cell
One (1)
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 38
Total number of cell
Six (6)
Nominal cell dimension
12.85 x 13.60 M
Over all tower dimension
78.76 x 13.96 M
Height of fan deck
12. 18 M
Fan stack height
3.2 M
Over all tower height
15.38 M
Inside basin dimension
78.16 x 15.60 M
Hot water inlet pipe points
Six (6)
Nominal dia.
32 (24)
Height of inlet pipe
9.26 M
Access to top of water
Stairway and cage ladder
Material Of Construction: Frame work
Reinforced concrete (RC.)
Casing
RC
Filling
Poly propylene (PP) Grid
Supports
304 SS
Drift eliminators
PVC
Spacer
PP
Fan stacks
FRP
Louvers
RC
Partitions
RC
Water distribution
Channel
Material
RC / HD4 Steel Pipe
Splashers of spray Nozzles
Poly propylene (PP)
Bolts, Nuts, washer
304 SS
Mechanical equipment support
HDG steel (Supplied by Hamon)
Anchor Bolts material
HDG Steel
Cold water basin
RC
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 39
First Time Water Filling / Cleaning:
First clean the basin toughly and fill it with raw water.
The feed valves to the cells are closed and only open flushing valve.
Pump the water round the circuit for some time, in order to clean the circuit. Under no circumstance the water from the first start up be fed to the cells since this water being dirty and is likely to block the nozzles.
Once the circuit has been properly flushed, the pumps are to be stopped, the basin emptied and cleaned out.
Fill the basin / bay again with water and start operation.
Start-up the pump, to avoid water hammering open the cell feed valves slowly.
Check the equilibrium of water distribution between the cells.
Check the water level of each cell under normal condition. Check the flow to ensure that the design flow is not exceeded. The Bay, Nozzles, Fill all are designed to tolerate only 15-20 % of increased flows then design condition.
OPERATION FIRST START-UP
Checks Before The First Start Up: 1.
First check fan shaft alignment maximum tolerance is 0.05 mm.
2.
Check the fan pitch.
3.
Check oil level in the gear box.
4.
Manual check of rotation of motor / fan unit.
5.
Ensure that no stray material like boards, ladders and tools are present their.
6.
Check the rotational direction of motor, if not correct reverse the terminal connection.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 40
Start Up Of Fans: The first start up of fan is done with no water flow.
Check that power is available.
Check the power requirement of fan and adjust its “Pitch” in accordance to power demand / ambient temperature.
Point: It is to be noted that more power is required when fan is running without load (with no water)
Check the bearing vibration / noise.
This process of fan operation should continue far one
Stop after one (1) hr of running and check all bearings / oil temperature.
If no overheating is found, then run for another “4 hour” and check temperatures of
hour.
oil and bearings again. No over heating of bearing is said to occur when temperature less than 40 oC.
RESTARTING AFTER A STOPPAGE
Preliminary Checks:
Check gear box oil level.
Check rotation of motor.
Check water level in Bay.
Check that vibration switch is on.
Check that no other material is present in the Bay, which can cause problem during operation.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 41
IGG (INERT GAS GENERATION) Purpose: The linde-PSA (Pressure swing adsorption) plant works according to the principle of “Adsorptive separation of air. The use of the adsorption technique in the recovery of gases is based on the ability of porous adsorption material. The loading capacity of gases depends on “pressure and temperature” and these two parameters are used to separate gases. About
98 % is removed from air (nitrogen) and remaining 2% oxygen is removed by
reacting with hydrogen in pressure of noble catalyst.
DESCRIPTION OF PROCESS Compression Ambient air will be compressed to a working pressure of 10 kg/cm2 by an “oil free screw compressor”. The moisture in air will be drained automatically in the shape of condensate.
Adsorption Water and CO2 will be adsorbed preferentially in the inlet zone after which O2 is adsorbed. The product N2 flows from the absorber out let to the N2 buffer vessel and then to the “deoxo system”.
Adsorption After the adsorption of water, CO2 and O2, the desorption of these gasses will be done to the atmosphere.
Pressurization After completion of the desorption process, the adsorption phase will start by pressure equalization between the two adsorbers. Further pressure will be developed with process air by the air compressor. The two absorber having the following cycles.
Adsorption (N2 production)
Desorption (Depressurization)
Again pressures build up.
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 42
Deoxydation N2 gas from PSA unit is fed to deoxy system where the rest of oxygen is removed by recombination with hydrogen. The gas is cooled by air and water; the condensed water will be drained.
Drying The remaining water is removed by means of an adsorption drier. The drier consist of two beds. One bed is in the adsorption mode and the other in the regeneration mode. Regeneration will be done by heating-up and then purging.
Safety 1.
Smoking and all naked flames are prohibited.
2.
Take special measures to avoid electrostatic charges. Do not wear shoes studded with iron nails.
3.
Parts exposed to O2 must be free from inflammable materials.
4.
The clothing of personnel must be free from any oil and grease.
5.
The greased parts must be cleaned only with “hydrocarbon chlorides” or “hydro carbon fluorine chlorides”.
6.
The storage of combustible material in plant area is prohibited.
7.
Prior to personnel entering to Nitrogen processing vessels and piping the equipment must be purged with dry air. The laboratory analysis must be done before vessel entry.
8.
It is prohibited to work in the area where concentration of N2 is more than the recommended.
DESIGN DATA Air Consumption
Air Consumption C-1161
Air consumption
1800 m3 /hr (process Air)
Design air inlet of adsorber
1340 Nm3 / hr.
Barometric Pressure (Inlet)
0.982 bar (a)
Ambient air temperature (Inlet)
+ 48 oC
INTERNSHIP REPORT (Pak American Fertilizer Limited)
| University Of The Punjab
Downloaded From : http://www.ICETStudentS.com
| 43
Relative Humidity
85 %
Outlet temperature of air
63 oC
Pressure of Air
0.982 bar (a)
Plant Capacity 1. Gaseous N2 product.
400 NM3 /hr.
2. O2 content
