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BETA Design and Construction Ltd. 12A Thornbury Court, London, TW7 4PP E:
[email protected] Tel: +44 77 33080854
Sulphonation and Washing Powder Plant Preliminary Process Design
Beta provides tailored engineering solutions to the Manufacturing, Energy, Housing and Government sectors. We carry out the engineering design, construction, and the project management. Our services meet the Clients’ Clients’ needs, budget and deadlines. deadlines. Our flexibility is our strength. Beta Design and Construction Ltd, Registered in England (No. 6921466, VAT No. 978 6872 35) Registered Office: 12A Thornbury Court, Church Road, Greater London, TW7 4PP, United Kingdom
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
Table of Contents 1.
Introduction................................................. .................................................................................................................................... ................................................................................... 3 1.1
.......................................................................... ...... 3 Background and Client Requirements ....................................................................
1.2
................................................................................................................................. .................................................................................. 3 Scope ...............................................
2.
..................................................................................................................... ...................................................................... 4 Executive Summary ...............................................
3.
..................................................................................................... ........................................................ 5 Growth of Detergents Market .............................................
4.
3.1
Market overview ............................................ ................................................................................................................ .................................................................... 5
3.2
............................................................................................................. ........................................... 5 Detergents in Iraq ..................................................................
Detergent Composition ........................................... ................................................................................................................ ..................................................................... 6 ............................................................................................................ ........................................................... 6 4.1 Phosphate Detergent ................................................. .................................................................................................... ........................................................ 7 4.2 Non-phosphate Detergent ............................................
4.3 Composition used for design ................................................. ............................................................................................... .............................................. 7 5.
................................................................................................................ ................................................................... 10 Sulphonation Sulphonation Process .............................................
5.1 Process Description ................................................................... ............................................................................................................ ......................................... 10 .................................................................................................................. ....................................................................1 5 5.2 Material Balance .............................................. ..................................................................................................................... .....................................................................1 8 4.3 Equipment List ................................................
6.
Washing Powder Plant ........................................... .............................................................................................................. ................................................................... 19 ............................................................................................................ ......................................... 19 6.1 Process Description ...................................................................
6.2 Material Balance .............................................. .................................................................................................................. ....................................................................2 1 ..................................................................................................................... .....................................................................2 3 6.3 Equipment List ................................................
7.
................................................................................................................................. .................................................................................2 4 Bibliography ................................................
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
1. 1.1
Introduction Background and Client Requirements
The Client is a group of Iraqi investors from the Kurdistan Region. For over ten years, they have been meeting the demand of the Iraqi market for detergents by importing washing powder. The Client plans to build a Washing Powder Plant with a production capacity of 10 tonnes per hour. The Client plans to build the Sulphonation unit to produce the LABSA raw material required for the washing powder production. The plant is to be based in Northern Iraq, City of Erbil, It is required that the detergent product is good quality low density detergent.
The Client has requested that all facilities be supplied by top reputed
international companies. 1.2
Scope
Beta Design and Construction is preparing this report is to establish a preliminary process design for a Sulphonation and Washing Powder Plant for our Client. This preliminary design will be the basis for preparing a proposal by Beta Design and Construction.
Figure 1 Erbil is the capital of the Kurdistan Region. Its Citadel is 8000 years old.
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
2.
Executive Summary
Beta Design and Construction is currently designing for a Client based in the city of Erbil, North Iraq, a safe part of the country. The Client plans to build a Sulfonation and Wasing Powder Plant with a low density good quality product, with a production capacity of 10tonnes/hr for an existing market which is being currently satisfied by imports. The Iraqi market values quality and with the expected rise in GDP the option of low density powder is favoured. It has been calculated that the Sulphonation plant would produce the surfactant LABSA (linear alkylbenezene sulfonic acid) at a production rate of 1.52tonnes/hr. It has been decided that a Sulphur burning plant would be built for the SO 3 (g) supply to the Sulphonation unit, other options have been considered such as the transport and storage of SO3(l) or the use of Oleum to produce it. However, they have been declined due to health and safety risks and the long term cost. Beta has decided that the air/SO 3 process is best suited in this design due to it being a large scale, continuous process with 24/7 detergent manufacture.
This process also has the
lowest material cost hence a reduced operational cost during the plants lifetime. Beta has chosen to use a Spray-Drying process for the manufacturing of the detergent due to the large quantity that is required for production and the high-quality that this process is capable of producing. It has been concluded that a non-phosphate detergent will be produced at the plant, due to the negative impact that phosphate detergents pose on the environment. Zeolite A will be the primary builder due to its biodegradability with small quantities of other environmentally friendly builders. The percentage composition of the detergent is displayed in Table 1 within the report.
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
3. 3.1
Growth of Detergents Market Market overview
Detergents can be found in many forms such as liquid, powder, paste or any moulded tablet shapes. Whilst their main function is for cleaning purposes, they have a global appeal and can be used in households, institutions or industrially. They were developed in response to the shortage of vegetable and animal fats during World War I and have been continued ever since, mainly due to their superior performance in cleaning. Demand of detergents is constantly mounting, primarily driven by the population growth. In developing countries an additional growth is seen due to the greater awareness of the benefits detergents can provide in comparison to the more traditionally used soaps. An additional surge in detergents is due to the increase in income and urbanisation in some regions. 3.2
Detergents in Iraq
One of the main detergent market holders in Iraq for detergents is ARADET, They produce phosphate and phosphate-free detergents.
They were built by Technipetrol, an Italian
company, at an estimated cost of $95 million US dollars to produce 50,000 tonnes per year of LAB (Linear Alkyl Benzene) in Baiji, North Iraq. The site is also used by the company for the manufacture of fertilizers and other such chemicals (APS Review Downstream Trends, 2005) (Farlex, 2005). However, currently most detergents are imported from Iran, Turkey, Syria, Jordan and countries in Southeast Asia. Currently, the Client is currently importing the detergent from Southeast Asia. The market currently exists and it is to be replaced by this Plant.
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
4.
Detergent Composition
There are two main types of detergents that are manufactured today; phosphate and nonphosphate detergents. 4.1 Phosphate Detergent
The most popular phosphate detergent that is often used is sodium polyphosphate (STPP), other phosphates such as sodium and potassium are often used for specific applications. The total world production of STPP is estimated at 4.7 million tonnes annually. The phosphates within the detergent act as a builder, their function is to ensure that the surfactant can perform its function of cleaning, which can be decreased due to the mineral ions present within the water.
The harder the water used for washing, the greater the
magnesium and calcium ions needing sequestering in order to allow the surfactant to work well.
However, phosphates have added functions, such as maintaining the pH of the
solution, the removal of dirt from textiles, it can act as anti-reposition chemical and also protects the washing machine against corrosion (Global Phosphate, 2011) (Yu, et al., 2008). Whilst they encompass various functions they have one important disadvantage. Phosphate detergents have a very catastrophic environmental impact. The impact was so great that it has lead to many European countries, Japan and the USA to ban the use of such detergents in the most urbanised areas (Environment, 2011). Households that use STPP detergents have an increased quantity of phosphate in their waste water, through drainage systems this phosphate eventually accumulates in rivers and inshore waters. Phosphates are a great fertilizer for algae, bacteria and other flora in rivers (Yu, et al., 2008). Therefore, the increase in phosphate in these waters causes eutrophication to occur, where an accelerated growth of green algae occurs covering the surface of the water and eventually destroying other forms of aquatic life within these waters.
The European
Commission Environment has published a report, where it was found that where phosphate detergents were still being used, 25% or more of the phosphate found in the local rivers where as a direct result of the STPP in those detergents. Overall, EU contributes less than 10% of the world’s total STPP production with the employment approximately 1000 people, furthermore EU is looking to expand the ban of STPP (Stafford, 24 June 2011) (E B G lennie, June 2002) . However, there is an alternative to the use of phosphates that is less polluting. 6
Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
4.2 Non-phosphate Detergent
Sodium aluminium silicates are non-toxic non-polluting chemicals that can be used to replace phosphates. Zeolite A particularly is commonly used for this purpose. However, unlike STPP Zeolite A cannot function as a buffer, does not prevent re-deposition of soil particles and whilst it has a ‘reasonable performance’ sequestering calcium and magnesium ions from the water it is not as effective at STPP. Therefore, Zeolite A is often used with cobuilders that can enhance its performance. The report published by the European Commission Environment found that no distinction was made between STPP and Zeolite A with regards to the cost of the detergent and its cleaning efficiency. Both types of detergents have been selling successfully in various parts of Europe where STPP is still sold.
Only minor differences were found in the overall
production cost between the two, whilst the Zeoloite A was also found to produce less polluting by-products when extracted from bauxite as opposed to the phosphate when extracted from rocks (E B Glennie, June 2002). 4.3 Composition used for design
A detergent is composed of many different chemicals that provide various contributions to the function of the end product.
There are four main categories; surfactants, builders,
additives and fillers 4.3.1 Surfactants
Surfactants are the primary cleaning agents within a detergent, they are the active ingredients. They act by reducing surface tension, wetting the surface thus removing and subsequently retaining the dirt into solution. LABSA (linear alkylbenzene sulfonic acid), which is adequately biodegradable, is widely used and will make up 15% of the detergent. 4.3.2 Builders
Builders have various functions that are vital for a detergent and therefore they must be chosen carefully to ensure all these needs have been fully satisfied. A builder must be able to reduce the water hardness, doing this will require the absorption or removal of calcium and magnesium ions present in regular tap water that can reduce the surfactant effectiveness and collect onto fabrics. They must be able to create and sustain the alkalinity required for the detergent to perform at its optimum level. The builder must help the dispersion of soil and dirt and prevent its reposition onto the fabric.
During
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
manufacturing they must contribute to the detergents low viscosity and easy fluidity. And finally they must be able to absorb the surfactants (Environment, 2011). Due to the toxic nature of STPP and the increasingly higher costs required for waste disposal, it has been decided to proceed with the manufacture of a non-phosphate detergent. 25% of the detergent will consist of Zeolite A, small amounts of other builders will be added to ensure this detergent has all the necessary properties to be a top quality product. We believe that a cleaner production will produce a product relevant to the future market needs and customer expectations. It will meet tight and strict regulations alike, improve the company’s image and performance whilst eventually leading to an increase in profitability. 4.3.3 Additives and Fillers
4% of Polycarboxylates will be added as a co-builder that will protect washing machines and fabrics by reducing the deposition of calcium and magnesium salts and maintaining them dispersed within the washing solution.
Polycarboxylates are poorly degradable and
therefore it is important a small amount is used within the detergent, whilst it is still enough to carry out the necessary function. Sodium Carbonate will be used to maintain the alkalinity of the detergent and inhibit corrosion. Whilst organic phosphates like EDTA will be used as a scale inhibitor. Sodium Perborate is to be used as the bleaching agent for the detergent, ensuring that stains are eliminated through chemical oxidation, the activator TAED is also to be used to allow the Sodium Perborate to be activated at low temperatures (below 60 oC). Enzymes aid the detergent by catalysing parts of the stains helping with their removal. Meanwhile, anti-redeposition agents such as the Carboxymethylcellulose that is to be used, repel dirt from fabrics preventing them re-depositing onto the fabrics. Perfume is used to make the detergent more enticing to the consumer. Finally fillers are used to adjust the percentage composition of the active components.
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
4.3.4
Composition Details
Table 1: The percentage composition of the detergent
Name of chemical
Function
% within detergent
Amount (ton/hr)
Zeolite A
Builder
25
2.5
Polycarboxylates (PCAs)
Water Softener, Co-builder 4
0.4
Organic Phosphonates (EDTA)
Water Softener
0.4
0.04
Sodium Silicates
Corrosion Inhibitors
4
0.4
Sodium Carbonate
Water Softener
15
1.5
LABSA
Surfactant
15
1.5
Sodium Perborate
Bleaching Agent
18
1.8
TAED
Activator
2.5
0.25
Sodium Sulphate
Filler
9
0.9
Carboxymethylcellulose
Anti-redeposition Agent
1
0.1
Proteases/lipases/amylases
Enzymes
0.5
0.05
Various combinations of scents Eg. Butylphenyl Methylpropional (lilac) + Geraniol (essential oil)
Perfume
0.2
0.02
Water
Filler
Around 5%
0.5
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
5.
Sulphonation Process
5.1 Process Description
Sulphonation is an industrial process used to make various products such as medicinals, dyes and organic intermediates. It is named after the chemical reaction that takes place where a sulfonic group is added (SO 3H), in this particular process LABSA will be produced from LAB in the chemical reactions depicted later. The Sulphonation process consists or an Air supply system and a Sulphur burning plant that deliver the raw materials required by the Sulphonator (air/SO 3), the Sulphunation Unit, Neutralisation Unit and the Gas Treatment Unit. During the designing of the plant there appeared to be four possible options to the delivery of SO3 to the detergent plant. The first was to transport and store liquid SO 3, however approximately 82 tonnes per week of SO 3 would be required and therefore large storage tanks are needed. A huge cost would be required to maintain these tanks over time at their optimum temperature. Transport and storage of this chemical is hazardous as liquid SO 3 reacts violently with water, it is highly corrosive and would cause serious burns to any persons that it comes into contact with. Since producing SO 3 from concentrated Oleum would still require the purchase and installation of added equipment, it was decided to use a Sulphur burning plant to supply to the sulphonation process. The Sulphur burning plant will pose an initial high capital cost, however it reduce the risks that SO 3 posses due to the fact that smaller amounts of it are being contained within the plant at one time. Over time, the capital cost will be made up by the reduced operational cost that will be required. Beta has also chosen to use air/SO 3 sulfonation process due to the high quality product that is obtained by this process. In addition less raw materials will be required for purchase and therefore an overall lower operational cost will be seen throughout the plant’s lifetime. The use of air/SO3 is also suited to this type of process which is for a large continuous 24/7 manufacture.
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
Figure 2: Sulphonation plants by left Desmet Ballestra, right iiT
5.1.1 The Sulphur burning plant
In order for SO 3 gas in air to be delivered to the sulphonator unit for the sulphonation to take place, liquid sulphur must be burned. The liquid sulphur must be delivered to the Sulphur Burner at 1:1 ratio. The reaction that takes place at the Sulphur Burner is as f ollows: S (l ) + O2 ( g ) → SO2 ( g )
The sulphur burner will also be connected to a tank of fuel - methane (CH 4) and a pump which will be necessary for plant start up purposes. Excess air will be available in the sulphur burner to ensure that all the sulphur present has reacted in order to reach the 99.9% sulphur efficiency, but also to ensure that the toxic sulphur does not pass un-reacted into the later stages as this can damage the catalytic reactor and its catalyst. The reaction depicted above is very exothermic to produce an outlet gas stream temperature of approximately 1048 oC and therefore the sulphur burner must be followed by a Water Tube Boiler that will cool the gas stream to 430 oC. The water tube boiler is a high pressure boiler in which water circulates around the tubes and is heated by the gas stream coming out of the furnace and entering the water tube boiler’s shell. A by-pass stream is located on the Water Tube Boiler which allows some of the gas to by-pass the cooling stage, this is mainly 11
Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
for control reasons. However the use of a by-pass is also to allow for fouling within the water tube boiler. With time fouling will build up within the water tube boiler causing it to be less efficient and this will result in lesser cooling. To overcome this problem the valve on the bypass will be tightened allowing less gas to bypass and a greater a volume to enter the water tube boiler to be cooled. The cooled SO 2 along with the other inert gases possessed by the stream will be then delivered to a Catalytic Reactor. The catalytic reactor contains 4 beds packed with the catalyst Vanadium (V) Oxide (V 2O5). The catalyst will help greatly in obtaining a good yield in the following reversible reaction: 2SO2
+ O2 ⇔
2SO3
The catalytic reactor will produce 99.9% conversion from SO 2 to SO3, for this to occur 4 beds will be necessary. The conversions that take place in each bed are as follows: 1st bed: 0%-65% SO3 conversion. 2nd bed: 65%-90% 3rd bed: 90%-96% 4th bed: 96%-99.9% Each catalytic bed is followed by a condenser in order to cool the gases down and in doing so obtaining a greater conversion to SO 3. According to the Le Chatelier’s Principle which states that if a dynamic equilibrium is disturbed by a change in conditions, the system m oves to counteract the change and thus restore equilibrium. Therefore the following factors are necessary in order to drive the reversible reaction to the right and obtain a greater conversion: 1. Decrease in temperature , as the reversible reaction above is exothermic and a decrease in temperature would bring about a system move to the right producing more SO3. 2. Pressure , an increase in pressure would result in the system wanting to reduce the
pressure and thus moving to the right where fewer molecules are present.
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
3. Concentration , the first bed has the greatest conversion due to the fact it has the greatest amount of reactants allowing for a shift to the right producing a lot of product. A great concentration in the product will unfortunately have the opposite undesired effect of fewer product being produced. This is counteracted with the use of an absorber in the third and fourth bed where conversion is at each smallest. The heat exchanger after the catalytic bed has the task of cooling the gas stream from approximately 620 oC to 440oC. After the second bed, the Heat Exchanger will cool the gas from approximately 512 oC to 450oC and then deliver to the third bed. After the third bed the stream will exit at approximately 467 oC and is fed into the fourth Heat Exchanger which will cool it to 267oC. The 99% SO3 gas stream will then pass through a Mist Eliminator where the traces of sulphuric acid/oleum formed are eliminated. It is the pumped to a tank where air/SO 3 ratio required is made up. 5.1.2 Air Supply
Air will be obtained from the atmosphere. Firstly it will be passed through an air filter to remove impurities, this step is vital as a small quantity of impurities could be passed to the later equipment and cause corrosion, damage or even initiate run-away reactions. The catalytic reactor is particularly sensitive to most impurities, as the Vanadium (V) Oxide catalyst within can be fouled, poisoned or denatured. Furthermore, any impurities that will pass on will result in an off-spec final product, this must be avoided at all costs. The air impurities vary geographically from country to country, some standard impurities are: dust, arsenic/mercury/selenium fumes, gaseous fluoride and chlorine. Water vapour within the air is also deemed as an impurity and it will eventually corrode the later equipment, catalyst and catalytic bed. However, complete air drying is unrealistic and small amounts of water vapour within the air will not cause much damage to the equipment and corrosion will take place at a slower rate and thus preventing high repair and maintenance costs. The air filter must be versatile and able to remove all the different impurities that are present. The air will then be dried in a dessicant dryer arrangement. 5.1.3 Sulphonation
Air with 7% SO 3 is pumped to the Sulphonator, where it is contacted with LAB and the following reaction occurs. 13
Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
The Sulphonator has a water cooling jacket to remove the heat of reaction. The inlet ratio between LAB and sulphur trioxide in air must be sustained to the pre-set value with little to no deviation.
LAB and SO 3 flow co-currently down the sulphonator column producing
LABSA (linear alkylbenzene sulfonic acid). The stream is then passed to the Cyclone where any un-reacted SO 2 or sulphuric acid is removed from the stream, the removed gases are cooled down by a Heat Exchanger and then sent to the Electrostatic Precipitator. The rest of the organic stream is first cooled then recycled back to the Sulphonator. The Electrostatic Precipitator this removes the SO 3 and sulphuric acid particles from the air using an electrostatic charge that is very efficient in comparison to other such type of scrubbers as it applies energy only to the matter that requires scrubbing (Chemithon, 2007). Some part of the recycle stream is taken out and pumped to the Digesters, where anhydrates are removed. The stream is then directed to the Hydration system where water is added. The stream is then cooled down and passed to the Neutralizer Unit, here Caustic Soda (36% NaOH) is added to neutralize the LABSA, as shown below.
A recycle stream exists in the neutralizer unit, where part of the stream is pumped up to a Heat Exchanger where it is cooled. After the Heat Exchanger a section of the stream is recycled back to the Neutralizer, and another section is taken out as the final LABSA product.
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
5.2 Material Balance
5.2.1 Sulphur Burning Plant
Figure 3: The Sulphur Burning diagram with labelled streams
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
5.2.2 Sulphonator
Figure 4: The Sulphonation Plant diagram with labelled streams.
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
Table 2: The material balance for the Sulphur Burning and Sulphonation plant.
Stream (tons / hr)
Name of Chemical
1
Air
2.45
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
0
0
0
0
0
0
0
0
0
0
6.57
0
6.57
0
0
0
0
Sulphur
0 0.49
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
SO2
0
0
0.49
0.49
0.17
0.17
0.05
0.05
0.02
0.02 0.00049
0
0
0
0
0
0
0
SO3
0
0
0
0
0.32
0.32
0.44
0.44
0.47
0.47
0.49
0
0.49
0.49
0
0
0
0
H2O
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0.68
LAB
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1.52
0
0
0
LABSA
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0 1.52
0
1.52
Caustic Soda
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4.2
0
2.45 0.49
0.49
0.49
0.49
0.49
0.49
0.49
0.49
0.49
0.49
0
0
7.06
1.52 1.52
4.2
2.2
Total
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
5.3 Equipment List 5.3.1
Sulphur Burning Plant
1 Sulphur Feed Tank, 1 Sulphur Burner, 1 Water-tube Boiler, 1 Kettle Boiler, 3 Shell and Tube Heat Exchangers, 1 Mist Eliminator, 1 Catalytic Bed Reactor with Vanadium (V) Catalyst. 5.3.2 Air Supply
1 Air Filter, 1 dessicant dryer system 5.3.3 Sulphonation Plant
1 Sulphonator, 5 Heat Exchangers, 5 Pumps, 1 Neutralizer Unit, 4 Storage Tanks, 1 Electrostatic Precipitator, 1 SO 2 Scrubber Tower, 1 Digester and Hydration unit, 1 Cyclone.
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
6.
Washing Powder Plant
6.1 Process Description
Beta has decided to use the Spray-Drying process for the production of this detergent. Spray-Drying processes produce the highest quality of detergent than any other process. The Blender process is most suited for smaller batch type processes and therefore it is unsuitable for use with the production rate of 10 tonnes/hr, whereas the Spray-Drying process is very suitable for a large scale continuous process such as this one.
The
Agglomeration process is another method that can be used to produce detergent, however this process does not produce the great quality detergent that is sought after by the Client and therefore this method is not applicable.
Figure 5: Spray-Drying Tower by left Desmet Ballestra and right iiT
Builder, surfactant and solid additives are stored in Silos, the Silos have De-dusting Filters to remove any solid dust that is produced.
The Silos deliver a certain amount of pre19
Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
determined weight to a Weight Conveyor, this is delivered to a Pre-mixing Screw where the solids are mixed evenly together. A De-ducting Filter is also present to remove dust that is produced on the Weight Conveyor, this air is filtered out, the solid is returned back to the Pre-mixing Screw and the remaining clean air is released to the atmosphere. Liquid Additives are delivered to a Liquid Vessel, where they are mixed and pumped to a Slurry Crutcher along with the Solid Additives. The mix is then transferred to a Magnetic Filter, where lumps that can clog Spray-Drying Tower nozzles are removed. The resulting stream is transferred to an Ageing Vessel, where it is homogenized. The stream is then separated into two and passed through another subsequent Filter to ensure that no clogging takes place. Any filtered out lumps removed by the Filters are transferred to a Recovery Slurry Vessel, which is filtered and pumped back as a Liquid Additive. After the Filters, the slurry is pumped to a High Pressure Pump, which pumps the slurry to a high displacement circuit that splits the stream into 4. These 4 streams are sprayed into the Spray-Dryer. A Hot Air-Generator supplies the Spray-Drying Tower with hot air needed for the drying to take place. The hot air flows in from the bottom of the Tower counter-currently at approximately 400 oC to the detergent falling from the top. Air is pumped into the Hot-Air Generator by a Combustion Air Fan.
The outlet air leaves the Drying Tower at a
temperature of approximately 85 OC to a De-dusting Filter that filters out any solid particles that have been transferred from the slurry and return it back to the Drying Tower. The air is then dried and fed back to the Hot-Air Generator. Subsequently, the dried slurry leaves the Spray-Drying Tower from the bottom and is transported by a conveyor belt to Crystallization Unit Conveyor where it is lifted to a height through cooling down the stream and crystallizing it. The stream is lead to a Vessel where it is dropped down to a Vibrating Sleeve that removes the wet agglomerated product, which is approximately 1% of the stream. The resulting product is then passed onto the Additives Mixer where perfume and enzymes are added. The final product can then be transported to packaging and storage.
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
6.2 Material Balance
Figure 6: The simplified detergent plant diagram with labelled streams.
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Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
Table 3: The detergent plant material balance
Stream (tons / hr)
Name of chemical
Purpose
%
Zeolite
Builder
25
2.53 2.53 2.53 2.53 2.53 2.53 2.53 0.00 0.00 0.00 2.53 0.00 0.00 2.53 0.00 2.50 0.00 2.50
Water Softener
4
0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.00 0.00 0.00 0.40 0.00 0.00 0.40 0.00 0.40 0.00 0.40
Water Softener
0.4
0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.00 0.00 0.00 0.04 0.00 0.00 0.04 0.00 0.04 0.00 0.04
Corrosion Inhibitors
4
0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.00 0.00 0.00 0.40 0.00 0.00 0.40 0.00 0.40 0.00 0.40
Water Softener
15
1.52 1.52 1.52 1.52 1.52 1.52 1.52 0.00 0.00 0.00 1.52 0.00 0.00 1.52 0.00 1.50 0.00 1.50
LABSA
Surfactant
15
1.52 1.52 1.52 1.52 1.52 1.52 1.52 0.00 0.00 0.00 1.52 0.00 0.00 1.52 0.00 1.50 0.00 1.50
Sodium Perborate
Bleaching Agent
18
1.82 1.82 1.82 1.82 1.82 1.82 1.82 0.00 0.00 0.00 1.82 0.00 0.00 1.82 0.00 1.80 0.00 1.80
TAED
Activator
2.5
0.25 0.25 0.25 0.25 0.25 0.25 0.25 0.00 0.00 0.00 0.25 0.00 0.00 0.25 0.00 0.25 0.00 0.25
8.3
0.91 0.91 0.91 0.91 0.91 0.91 0.91 0.00 0.00 0.00 0.91 0.00 0.00 0.91 0.00 0.90 0.00 0.90
1
0.10 0.10 0.10 0.10 0.10 0.10 0.10 0.00 0.00 0.00 0.10 0.00 0.00 0.10 0.00 0.10 0.00 0.10
Polycarboxylates (PCAs) Organic Phosphonates Sodium Silicates Sodium Carbonate
Sodium Filler Sulphate Carboxymethyl Anti-redeposition -cellulose Agent
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
Enzyme
Enzymes
0.5
0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.00 0.00 0.00 0.05 0.00 0.00 0.05 0.00 0.05 0.00 0.05
Agents
Optical Brightening Agnets
0.2
0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.00 0.00 0.00 0.02 0.00 0.00 0.02 0.00 0.02 0.00 0.02
Perfume
Perfume
0.2
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.02
Water
Filler
5.9
11.80 11.80 11.80 11.80 11.80 11.80 11.80 0.00 0.00 11.21 0.59 11.21 11.21 0.59 0.00 0.59 0.00 0.59
Air
Dryer
0
0.00 0.00 0.00 0.00 0.00 0.00 0.00 14.70 14.70 14.70 0.00 14.70 14.70 0.00 0.00 0.00 0.00 0.00
Total
100
21.35 21.35 21.35 21.35 21.35 21.35 21.35 14.70 14.70 25.91 10.15 25.91 25.91 10.15 0.00 10.05 0.02 10.07
22
Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
6.3 Equipment List
4 Storage Silos, 4 Weight Conveyors, 1 Slurry Crutcher, 4 Liquid Tanks, 1 Liquid Vessel, 1 Magnetic Filter, 1 Slurry Ageing Vessel, 2 Filters, 1 High Pressure Pump, 1 Spray-Drying Tower, 1 Hot Air-Generator, 1 Drying Air Extraction Fan, 1 Combustion Air Fan, 1 Air Lift Feeding Belt, 1 detergent Powder Vibrating Sleeve, 1 Recovered Slurry Vessel, 1 Slurry Filter, 2 Tanks, 1 Rotary Mixer, 9 Pumps, 6 De-dusting Filter.
23
Sulphonation and Washing Powder Plant Erbil, Iraq Preliminary Process Design Dec 2011
7.
Bibliography
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http://www.allbusiness.com/mining/oil-gas-extraction-crude-petroleum-natural/414803-1.html. Ballestra, Desmet. Desmet Ballestra. [Online] [Cited: 15 12 2001.]
http://www.desmetballestradsc.com/technologies.html. Chemithon. 2007. Sulfonation and Sulfation Processes. 2007. E B Glennie, C Littlejohn, A Gendebien, A Hayes, R Palfrey, D Sivil, K Wright. June 2002. Phosphates and Alternative Detergent Builders-Final Report. s.l. : WRc plc, June 2002. Environment, European Commission. 2011. Phosphates and Alternative Detergent Builders. European Commission Environment. [Online] 16 11 2011. [Cited: 05 12 2011.]
http://ec.europa.eu/environment/water/pollution/phosphates/index_en.htm. Farlex. 2005. IRAQ - The Arab Detergent Chemicals Co. (Aradet). Thefreelibrary.com. [Online] 2005.
[Cited: 03 12 2011.] http://www.thefreelibrary.com/IRAQ++The+Arab+Detergent+Chemicals+Co.+%28Aradet%29.-a0132237003. Global Phosphate. 2011. Phosphates in Detergents. Global Phosphate Forum. [Online] 2011. [Cited:
05 12 2011.] http://www.phosphate-forum.org/index.php?option=com_content&task=view&id=18. iiT. iiT Sulfonation Technologies. [Online] [Cited: 15 12 2001.]
http://www.iitsrl.it/spray_drying_Powder_Detergents.html. Stafford, Ned. 24 June 2011. EU looks to expand ban on phosphates in detergents. Hamburg,
Germany : RSC Advancing Chemical Sciences, 24 June 2011. http://www.rsc.org/chemistryworld/News/2011/June/24061105.asp. Yu, Yangxin, Zhao, Jin and Bayly, Andrew E. 2008. Development of Surfactants and Builders in Detergents Formulations. s.l. : Chinese Journal of Chemical Engineering, 2008.
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