INDUSTRIAL TRAINING IN
Petrochem Limited. “INTERNSHIP REPORT & PROJECT WORK”
SUBMITTED BY:
SUBMITTED TO:
Himanshu Agnihotri
PLASTIC DEPARTMENT HBTU KANPUR
IIIB.Tech,PlasticTechnology
HarcourtButlerTechnicalUniversity,Kanpur
ACKNOWLEDGEMENT 1
This Internship was supported by IVL Dhunseri. We thank the personnel of IVL Dhunseri, who all provided insight and expertise that greatly assisted the internship. We thank Mr. T.K Giri, Sr. Manager (HR & Admin) and Mrs. Anandita Paul (HR) for making possible for us to get involved in the internship. We are especially thankful to Mr O.R.K. Reddy (SGM, Process) for their valuable guidance and cooperation. We would also like to show our gratitude to and Mr. Swaroop Paul (Process head, Plant-2) for sharing their pearls of wisdom with us during the course of this internship. With grateful heart, we would like to all the personnel who all helped us to commence a successful training. We would also like to thank entire DPL family for their co-operation, valuable guidance and support.
Mr. O.R.K Reddy
Mr. T.K Giri
(SGM, Process)
Sr Manager (HR & Admin)
PREFACE
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In-plant training plays a vital role to connect the theoretical knowledge to the practical insights and this is our first practical knowledge with the theoretical concepts acquired during the years in technical University. We are fortunate that we got the opportunity of undergoing summer training in most sophisticated and modern PET plant, ‘IVL Dhunseri, Haldia’. The experience gained during this short stay was fascinating to say the least. It was a tremendous feeling to see the practical operation of different equipment and processes, whichstill until now existed for the us only in the books of college library. What fascinates us, how plant is being monitored and operated with such a high precision and accuracy to get the desired result. In this short period, it was not possible for us to wholly decipher the detailed functioning of the plant; but still we are fortunate enough to get a sound overview of it. Thanks for the guidance extended by the people in the different sections of the plant. We also undertook a project on “Design of a plate type heat exchanger in Cutter demineralised water system”. Finally, after this small tenure we feel that nothing is more practical than a good theory. So we realized that to be successful as a process engineer or for that matter any engineer one needs to possess a sound theoretical base along with the acumen for effective practical application of the theory.
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Dhunseri tea Company (DTCL) was incorporated in 1961. The S L Dhanuka group took over the management of the company in 1955 from James Finlay & Company. In 1970, the company was renamed Dhunseri Tea & Industries. In 1980, the company acquired the Namsang and Dilli Gardens in Assam. It took over Bahadur Tea Company and amalgamated it with DTCL on 1 Apr.'91. In 1994, it acquired three more tea estates Santi tea estate, Khetojan tea estate and Khagorijan tea estate. Santi tea estate was amalgamated with DTCL on 1 Apr.'93. The company has 1248 hectares of plantation area in Assam. It came out with a public issue in Dec.'92 and a rights issue of NCDs with detachable warrants in Jul.'94. The funds from the rights issue were utilised to acquire the three tea estates mentioned above and to expand manufacturing facilities. DTCL cultivates and sells tea in packed form. DTCL also has a pharmaceutical division called Iveon Laboratories (ILL). It produces IV fluids with the latest FFS technology. In 1993, the company expanded the production capacity from 35 lac bottles pa (LBA) to 167 LBA. The company has set up packaging plants near its gardens, and markets them under the LalGhora and Kala Ghora brands. 5
During 1998-99, the Company raised a sum of Rs. 8 Crores by issue of 15% Secured Non-Convertible Debentures on private placement basis with financial institutions to augment long-term resources of the Company for working capital requirements. The company has promoted South Asian Petrochem Ltd., a 100% E.O.U. petrochemical project at Haldia, West Bengal, for manufacture of PET Resins under technical and financial collaboration with Lurgi Zimmer AG of Germany, during the 1999-2000. The 100% EOU petrochemical project viz South Asian Petrochem Ltd was completed ahead of schedule. The Technical and Financial collaboration was done by Zimmer AG, Germany.
The plant at Haldia spreads over some 35 acres, also has a 12 MW captive power plant. Erstwhile South Asian Petrochem Limited (since merged with Dhunseri Petrochem & Tea Ltd.) (“DPTL” or “the Company”) which started operations in 2003 is the second largest producer of food grade polyethylene terephthalate (PET) in India. This unit consists of two plant for manufacturing PET. There are 2 technologies that are employed: 1. ORLICON BERMACK Dhunseri Petrochem Theplant-1 uses world class German technology known a & Tea Ltd (DPTL) commissioned a Rs.4 billion for this plant to manufacture polyethylene terephthalate (PET) at Haldia, West Bengal. This unit is the company's second plant at Haldia. DPTL already had a 2,10,000 tonnes per annum PET manufacturing facility there. With commissioning of this new plant (Plant-2), which is based on the technology knowns as ORLICON BERMACK, total PET capacity of the company has increased to 4,10,000 tonnes per annum. Presentlythe plant1 and plant 2 produces 605 and 800 Tons/day respectively. DPTL is a part of Kolkata (Calcutta) based Dhunseri Group (“Dhunseri” or “the Group”), promoted by Mr. C.K. Dhanuka and Family (the “Sponsors” In the year 2009-10, appx. 40% of the total sales of the petrochemical division of DPTL are accounted for by exports to over 29 countries of which 78% comes from exports to the U.S. and European Union countries.
Full Company Name: IVL Dhunseri
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IVL Dhunseri enjoys a marketing presence covering around 500 PET consuming customers in around 50 countries. Its products are available in the ASPET brand in , the , the , . To help deal with its international operations better, DPL established a branch office in Authority under the name of Dhunseri Petrochem & Tea Ltd.
Product of the company is approved by international & national regulatory bodies:
American FDA regulations covering Federal Food, Drug & Cosmetics Act European EC Pepsi Worldwide Bureau of Indian Standard Regulations Japan Polyolefin Association Canadian Health Authorities Coke-India
DPL enjoys a marketing presence covering around 500 PET consuming customers in around 50 countries. Some of the leading customers around the world are:
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Pepsi Hindustan Coca Cola Umrao polymers Bisleri Aquafina Vishal polypack
There arethe multiple companies in the field of PET production. Some of leadingleading esteemed organization:
RELIANCE PEARLPET FUTURA POLYMERS JBF INDUSTRIES
DPL Haldia plant produces PET resin. It manufactures the finest bottle grade PET resin ASPET (brand name) for following applications: Packaging of drinking water Carbonated soft drinks Edible oil Pharmaceuticals etc.
IUPAC NAME-Polyethylene terephthalate CHEMICAL STRUCTURE-
PHYSICAL PROPERTIES PET in its natural state is a colourless, semi-crystalline resin. Based on how it is processed, PET can be semi-rigid to rigid, and it is very lightweight. It makes a good gas and fair moisture barrier, as well as a good barrier to alcohol (requires additional "barrier" treatment) and solvents. It is strong and impact-resistant.
σ 8
Because PET is an excellent water and moisture barrier material, plastic bottles made from PET are widely used for soft drinks (see carbonation). For certain specialty bottles, such as those designated for beer containment, PET sandwiches an additional polyvinyl alcohol (PVOH) layer to further reduce its oxygen permeability. Biaxially oriented PET film (often known by one of its trade names, "Mylar") can be aluminized by evaporating a thin film of metal onto it to reduce its permeability, and to make it reflective and opaque (MPET). These properties are useful in many applications, including flexible food packaging and thermal insulation. See: "space blankets". Because of its high mechanical strength, PET film is often used in tape applications, such as the carrier for magnetic tape or backing for pressure-sensitive adhesive tapes. Non-oriented PET sheet can be thermoformed to make packaging trays and blister packs. If crystallisable PET is used, the trays can be used for frozen dinners, since they withstand both freezing and oven baking temperatures. As opposed to amorphous PET, which is transparent, crystallisable PET or CPET tends to be black in colour. When filled with glass particles or fibres, it becomes significantly stiffer and more durable. PET is also used as a substrate in thin film solar cells. Terylene (a trademark formed by inversion of (polyeth)ylene ter(ephthalate)) is also spliced into bell rope tops to help prevent wear on the ropes as they pass through the ceiling. PET is used since late 2014 as liner material in type IV composite high pressure gas cylinders. PET works as a much better barrier to oxygen than earlier used (LD)PE.
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.
PET in its natural state is a colourless, semi-crystalline resin. Based on how it is processed, PET can be semi-rigid to rigid, and it is very lightweight. It makes a good gas and fair moisture barrier, as well as a good barrier to alcohol (requires additional "barrier" treatment) and solvents. It is strong and impact-resistant. PET becomes white when exposed to chloroform and also certain other chemicals such as toluene. The raw materials to make PET are monoethylene glycol (MEG) and purified terephthalic acid (PTA) or dimethyl terephthalate (DMT). PTA is the preferred feedstock for process economic reasons although DMT may be favoured in polyester film applications due its adhesion addition quality. The main process steps are raw material preparation, esterification/transesterification, pre-polycondensation and polycondensation. The PTA is mixed with the MEG and catalyst solution in a paste and fed into the esterification system. The esterification takes place under atmospheric pressure by splitting off the water. Monomer (bis βhydroxyterephthalate) can be synthesized by the esterification reaction between terepthalic acid and ethylene glycol with water as a by-product, or by transesterification reaction between ethylene glycol and dimethyl terephthalate with methanol by product. Polymerization is through a polycondensation reaction of the monomers (done immediately after esterification/ transesterification) with water as by product.
Polyethylene terephthalate may exist both as 10
Amorphous (transparent) semi-crystalline polymer.
The semi crystalline material might appear transparent (particle size < 500 nm) or opaque and white (particle size up to a few microns) depending on its crystal structure and particle size
IUPAC Name: Purified Terapthalic Acid Formula: C6H4(COOH)2 Chemical structure:
Mitsubishi Chemical Private Industries Limited (MCPI), Haldia Indian Oil Corporation Limited (IOCL), Panipat Mitsubishi Chemical Indonesia, Indonesia NPC, Japan Sahid Tondgooian Petrochemical Co., Turkey
IUPAC Name: Ethane-1,2-diol Formula: C2H6O2 Chemical structure:
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−
−
−
Saudi Arabian Basic Chemical Industries (SABIC) Indian Glycol Limited (IGL) , RIL, IOCL.
IUPAC Name: Isophthalic acid Formula: C6H4(COOH)2 Chemical structure:
Interquisa (Spain) K.P. Chemicals Corporation (Korea) A.G. International Chemical Company (Japan) LOTTE(Korea)
IUPAC Name: 2-(2-Hydroxyethoxy) ethane-1-ol Formula: C4H10O3 Chemical structure:
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IUPAC Name: Antimony(III) trioxide Formula: Sb2O3 Chemical structure:
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α Guangzhou chemical corp.
β
Suppliers – Color Matrix Europ Ltd.
SuppliersIOCL (Indian Corporation Oil Corporation BPCL (Bharat Petroleum Ltd)Ltd)
Therminol 66 is a high performance highly stable synthetic heat transfer fluid offering extended life and very low top-up rates resulting in reduced running costs and minimal downtime for operations at temperatures up to 345°C. Therminol 66 derives its outstanding performance from the unique stability of the polyphenyl structure. 13
Intended for use in systems operating at or near atmospheric pressure, Therminol 66 offers potential savings in both capital and operating costs. Therminol 66 is in use world-wide for many process heating and waste heat recovery applications: resin manufacture, phthalic anhydride distillation, polyester film and fibre production, phenol production, polyamide polymerisation and extrusion, preheating combustion air in the steel and petrochemical furnaces.
The polymerisation reaction takes place into several steps divided into 2 different processes. The entire process is divided into two main processes are– 1. Continuous Polycondensation (CP) 2. Solid State Polycondensation (SSP)
Below present flow diagram shows a brief description of the process:
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Condensation polymerization, a form of step-growth polymerization, is a process by which two molecules join together, resulting loss of small molecules which is often water. The type of end product resulting from a condensation polymerization is dependent on the number of functional end groups of the monomer which can react. The monomers that are involved in condensation polymerization are not the same as those in addition polymerization. The monomers for condensation polymerization have two main
The monomers that are involved in condensation polymerization are not the same as those in addition polymerization. The monomers for condensation polymerization have two main characteristics:. Instead of double bonds, these monomers have functional groups (like alcohol, amine, or carboxylic acid groups). Each monomer has at least two reactive sites, which usually means two functional groups. Instead of double bonds, these monomers have functional groups (like alcohol, amine, or carboxylic acid groups). Each monomer has at least two reactive sites, which usually means two functional groups.
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Since step-growth polymerization reactions are reversible. It is more straightforward to recycle many step-growth polymers back to monomers or oligomers.
The basic raw materials for the production of PET are Purified Terephthalic Acid (PTA). PTA is in powder form and received in container or in jumbo bags of capacity 1150 kg each. PTA powder is conveyed with nitrogen by means of TCC or tube chin conveyer and stored in silo (150 m3). For unloading of PTA from jumbo bags, five charging stations are available. Unloading of EPTA have two methods to unload in hopper. One is directly by to hopper and other is opening of on hopper. Which is show below in figure.
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Each jumbo bag is manually lifted by means of hoist and charged through charging stations. For conveying of PTA, tube chain conveyer (TCC) and Pneumatic conveying system area used. Nitrogen is used in pneumatic conveying. The nitrogen is being compressed, the temperature is raised and hence it is cooled using a discharge cooler, which is nothing but a shell and tube heat exchanger. Nitrogen passes on to the tube while the coolant (water) flows within the shell. Nitrogen at high pressure is cooled around 60 0C to 70 0C. There is a water separator which separates the water from the Nitrogen. There is a similar discharge filter which filters any impurity present in Nitrogen and passes onto two lines- one goes to big bag conveying and another goes to bulk unloading i.e., 20 tons. The hopper consists of two lock feeders—one at the top and other at the bottom. They are nothing but rotating blades arranged in circular manner. The first lock feeder carries PTA to the bottom of hopper, while the 2nd one carries it to the inlet of the pipeline wherefrom compressed N2 conveys it to the PTA storage silo. PTA from here goes to feed silo wherefrom it is being used to run the process plant. From feed silo PTA is fed for processing into first vessel that is Paste preparation tank by means of screw feeder.
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MEG is a colourless, transparent liquid and received in storage tanks of capacities 3000 KL (4 tank) and 4000KL (2 tank) pumped into the main process building.
IPA is in solid powder form and is used for reducing the melting point and to enhance clarity. It is received in jumbo bags of 1100 kg capacity. Each bag is manually lifted by means of hoist & charged into IPA feed silo. From feed silo it is fed into the paste preparation tank for processing by means of screw feeders.
It is in powder form & is received in 15 kg buckets. It is used for enhancing polycondensation rate of reaction. Catalyst batch system comprises of preparation vessel & feed vessel. Depending on plant capacity a catalyst batch is prepared in preparation vessel. Catalyst batch is prepared with MEG, antimony trioxide & blue toner in preparation vessel. After agitation & on clearance of sample for concentration from quality control (QC) lab one batch is ready in preparation vessel. Depending on the requirement the batch is manually dropped to the catalyst feed vessel by opening manual valve. The catalyst solution in glycol from catalyst vessel is fed to the paste preparation tank by means of pump.
It is in powder form and is received in 5 buckets. It is a colouring agent and makes the polymer shiny. Its batch system also consists of a preparation vessel and a feed vessel. Depending on plant capacity its batch is prepared in MEG in the preparation vessel. After agitation and on clearance from QC the batch is ready. From where it is manually dropped to the feed vessel. This solution in glycol is transferred to the paste preparation tank by means of pump.
It is in liquid form and is received in 25 litres cans. It is used for thermal stability of the polymer. Its batch system also consists of preparation vessel and feed vessel. Depending on plant capacity phosphoric acid batch is prepared in preparation vessel. The phosphoric acid batch is prepared by taking MEG in preparation vessel and phosphoric acid is added in this tank. After agitation and on clearance of sample for concentration from QC one batch is ready in preparation vessel. Depending on requirements the batch is manually dropped from preparation vessel to feed vessel.
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The raw materials PTA & MEG are metered quantified and mixed in the paste preparation vessel to make thick paste. PTA & MEG are normally mixed in a mole ratio of 1:1.15. For bottle grade PET resin production, the co- polymer IPA & DEG are metered and added into paste preparation vessel. DEG addition is around 0.5% -0.6% and IPA addition is around 1.9% by weight of PET. As a concentration of 0.9% of DEG evolves during the manufacturing the PET thus Antimony produced shall have is around DEG and 1.8% of IPA respectivelyprocess, by weight of PET. triacetate added1.7% as aofcatalyst into paste preparation vessel. Cobalt acetate and Blue Toner are added to paste to improve the colour of PET.
The paste from the paste preparation vessel is fed into ES-1. Here the product temperature is maintained at 265 0C- 270 0C. The MEG vapour pressure can be increased above the atmospheric pressure so that the reaction rate is improved. Thus, owing to a residence time, operating temperature of reactance and the vapour pressure, the esterification reaction proceeds liberating waste water as the by product. In this unit conversion of reaction occurs from 90% to 92%. As esterification reaction occurs at high temp so we used HTM in coil and Dow vapour in the jacket of the reactor as a heating medium. Dow vapour comes from HTM evaporator where Dowtherm is evaporated by using HTM.
The product BHET (Bis hydroxyl ethylene terephthalate) from ES-1 is then fed into ES-2 through product transfer pump, where the conversion is further increased from 92% to 97%. Phosphoric acid is added here from a separate tank and it acts as a heat stabilizer, as it is ES-2 where the transition from BHET to PET begins, moreover if added before it can deactivate the catalytic properties of Antimony triacetate and hence added only when the BHET to PET transformation is complete. In ES-2 the temperature is maintained at 266 0C. Here also temperature is maintained by supplying HTM in coil and Dow vapour in the jacket of the reactor as a heating medium. Dow vapour comes from HTM evaporator where Dowtherm is evaporated by using HTM.
The product from ES-2 is transferred to PP-1 by gravity. The reactants are at a temperature of 270 0C. A vacuum level of 100 mbar (abs) is maintained with the help of vacuum pump. Under the catalytic action of Antimony trioxide, the prepolycondensation reaction starts from here at higher product temperatures and under vacuum. Here degree polymerization is near about 30. Here is no sampling point as to maintain the vacuum pressure. Here also 19
temperature is maintained by supplying HTM in coil and Dow vapour in the jacket of the reactor as a heating medium. Dow vapour comes from HTM evaporator where Dowtherm is evaporated by using HTM.
The product from PP-1 is transferred by gravity to PP-2. Here the product temperature is further increased to around 275 0C and a vacuum level of around 10 mbar (abs) is maintained. Temperature is maintained by passing HTM in the jacket of the reactor and the vacuum pressure maintained by jet ejector and vacuum pump. Here degree polymerization is near about 60-65. An agitator is attached to the reactor that keeps on revolving in clockwise direction that stirs up and mixes up the content of the reactor. The reactor is kept in horizontal supine so as to provide a larger surface area for MEG to get liberated from the surface of the polymer.
The product from PP-2 is then transferred to Finisher with the help of prepolymer feed pumps. The product temperature at the exit of Finisher is 280 0C. The vacuum level in Finisher is fine and is around 1.22-1.5 mbar (abs). In Finisher, the vacuum is achieved with the help of EG vapour jet ejector and the vacuum pumps (Rotajector). Here degree polymerization is near about 99.9%. During the process of polycondensation the excess EG keeps getting liberated which in turn keeps increasing the viscosity of the polymer. In PP-2 and Finisher the EG liberation is enhanced by the polymer film formation due to the agitation of the contents. Thus at PP-1, PP-2 and Finisher outlets the Intrinsic Viscosity (IV) are around 0.18, 0.27 and 0.61-.63 dl /g respectively. The EG that liberates in the polycondensation steps is condensed in the scrapper-condenser of each polycondensation loop and recycled to paste preparation vessel, ES-1 and ES-2 reactor.
The MEG vapours in plant 2 go along with water vapours from both ES-1 and ES-2 go into the process column where the water is distilled and taken out as distillate. A portion from the reflux vessel where the distillate gets collected is recycled to the process column 20
and the rest is sent to the effluent treatment plant. The EG obtained, one part is transferred into the paste preparation tank and another part goes to the EG tank. Here the average temp of the process column is to maintained 130 0C to 1450C. In this process column number of trays is 16 and we used bubble cap trays.
: From the the polymer under pressure comes to gear pump with the help of gear pump It goes via 4-way valve to the respective filter to . Each filter has 79 candles or filter elements with 40-micron mesh size, these filters filter contaminants coming with raw materials and in process generated. Then the filtered polymer goes to a section known as where there are 112 holes, here the polymer comes in contact with demineralize water (if DM water is not used the polymer would get oxidized resulting in yellow coloration of chips). DM water to each cutter is supplied in three ways – 1st the overflow water which comes from the back side at a flow rate of 7 m3 /h, 2nd sprayed from the nozzle at a rate of 15 m3 /h. Here the polymeric strands get solidified coming in contact with water fed to cutters where thus chips are produced. Thereafter chips conveyed using conveyor water at a rate of 22 m3 /h to dryer where chips get dried and screened in classifier accordingly so that the large size crystal can be separated in a separate bag. This product is amorphous PET (APET) having crystallinity 5% to 10% and IV is around 0.61-.63 dl /g. The molecular weight of APET is around 1800020000. This product is then sent to another section for further IV build up. Sometimes APET may also be sold. Before being sent to the SSP unit the chips are stored in Amorphous pet silos.
According to the post-SSP method, after polycondensation in the melt phase, the molecular weight of the resultant polymer is further increased in the solid-state polycondensation. SSP is also an efficient recycling technique through which the molecular weight of the postconsumer polymer such as PET is increased, and the resulting material can be processed without mechanical properties deterioration.
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• Used in the final stages of some polymer production processes (e.g., nylon, polyester and polycarbonate production) to produce very high molecular weight polymers. • Molten low molecular-weight polymer is cooled and formed into solid particles (by extrusion or by spray drying). • In the solid-state reactor, the pellets are held at temperatures above the glass transition temperature (but
The precystallizer is a non- vibrated fluidized solid bed cross flow type where air is blown from bottom to top and granules are held by a special perforated sheet and forwarded from side to side. The amorphous PET with IV 0.61-.63 dl/gm is processed in SSP to get an IV lift up to 0.880 dl/gm or mores per market demand. We have two SSP lines A&B each of 240 tons/day. The amorphous PET chips are conveyed into chip dosing vessel depending upon the requirement. The chips flow by gravity via a rotary lock feeder into the precrystallizer. Here the chips are fluidized by hot N2 increasing the chips temperature to 180 0C. Owing to high turbulence of chips in the fluidized bed and due to the residence time (around 15 minutes) the chip gets crystallized to a crystallinity level of 40%-42%. Here one Precrystallizer cyclone is present to remove the dust particle. The crystallization process is highly exothermic and may result in the lump formation of chips in the precrystallizer inlet. The operation of the 22
precrystallizer is carried out by optimizing the N2 gas temperature and flow. In the first and second zone the temperature and flow rates are around 150 0C, 26000m3/hr and 180 0C, 12000m3/hr respectively. The circulating N2 gas is heated up in a finned tube heat exchanger with liquid HTM flowing through the tubes.
The precrystallizer product (chips) then comes into First crystallizer by gravity. In the First crystallizer. We have, two paddles rotating in opposite direction and with liquid HTM flowing through the paddles from inside. A negative slope to facilitate better chips movement towards the outlets. Jacket of the crystallizer heated up with liquid HTM. Sweep N2 to carry away the chips dust caused by the rotation of the paddles. The chips at the inlet are at around 189-190oC and the outlet at around 191-192oC maximum.
The First crystallizer product then comes into another crystallizer called as Second crystallizer. In second crystallizer N2 flows a direction that is oppositeare to at thearound falling205chips from First crystallizer. The chips at theininlet of second crystallizer o o 207 C and the outlet at around 208-210 C
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The final crystallizer product (chips) then comes into SSP reactor. In the crystallizer the chips fall from the top to bottom and heating material (hot Nitrogen) goes from bottom to top. As the temp of the chips changes, viscosity changes. The average temp of the reactor is 205 0C -210 0C and the residence time in the reactor 14~18 hours (depending upon the IV of the products) and the Nitrogen gas flow rate is 3200-3500 Nm3/hr. The IV of the chips is increased here in the SSP reactor up to 0.75 dl/gm or more.
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The rise in IV in SSP reactor is influenced by(1) Initial IV of the base chips (2) Catalyst concentration (3) Carboxylic end group (4) Chip size (5) Residence time (6) N2 gas flow to the reactor (7) Dew point of circulating N2 gas (8) Temperature
In all these 4 units i.e. precrystallizer, first crystallizer, second crystalliser, SSP reactor the surface EG is removed from the crystalline substances at high temp (400 oC) is as follows:
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The Nitrogen in plant 2 at (low temp) which comes from precrystallizer, final crystallizer, two units is passed through an economizer (1) and is heated by the Nitrogen coming from the oxidation unit. It is then passed through an electrical heater (as per reaction temp requirement) and goes to oxidation reaction unit which contain Pt catalyst by means of a pump.
N2 carries out surface EG from chips and following reaction takes place;
CH2OH-CH2OH
CH3CHO
(Pt catalyst and high temperature)
H2O + CO2
(350~375degree Celsius)
There are 8 PET storage silo 4 for amorphous chips and 4 for crystalline. The bagging section consist of total 6 filling sections four for the crystalline chips and two for amorphous chips. The volume of amorphous silos are 1000m 3 (2 silos) and 300m3 (2silos) and the volume of the crystalline Pet chips silo are 500(2silos and 250 m 3 (2 Silos). The grades are according to the I.V. of the chips which is set according to the market demand. For crystalline there are five grades 18C, 19C, 20C, 21C and 21CF having label colour blue, green, white, red and white with red stripes respectively and for amorphous it has only one grade i.e. 16C. bagging is done in different weights depending upon the demand it consists of mainly 25kg, 1tone,1.05 tone, 1.1 tone and 1.15 tone bags. The jumbo bags are hooked on 4 sides with pneumatic air cylinders and filling rate is 50 kg per dump and total is 23 dumps for ASPET bagging and 20 dumps for APET bagging and bagged. Each bag has a barcode describing its filling section, date, month, year and bag number for example consider the bar code given below 26
It can be decoded asQ– Describes the bagging section 17 – It gives the year that is 2017 U- Month (June) 27- Date 0080- Gives the bag number There are four filling sections for crystalline having a specific latter assign namely T, R, Q and S and for amorphous filling section letter O is assign. For months the letter which is written in front of the corresponding name of the month is used, the list is given bellowJanuary-Z February-Y March- X April-
W
May-
V
June -
U
July -
T
August – S September – R October – Q November- P December –O In case of 25 kg bags they are kept in lots each lot consist of 440 bags and the total weight of single lot is 11 tons. Each ton has 40 bags and a barcode. On the bag numbers along
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with the letter describing lot number and PET grade are written on it, the letter describing the grade are
Y-21C
X-20C
Z-22CJ W- 19C For example, consider Y0481 here Y tells the grade and 0481 tells the lot number. After filling the bags are sealed and kept at specific location in the bagging area. The whole bagging area is divided into 4 columns A, B, C, and D ranging from right to left respectively and in 13 rows from 1 to 13. Each bag is kept at specific location to avoid mixing of a bag with a particular grade with other bags having different grade and easy loading and unloading of bags into the trucks
Different specifications of the bags in plant 2:
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dl/gm meq/kg
0.625 +/-0.01 35 max
0.76 0.80+/- 0.84+/- 0.84+/+/-0.02 0.02 0.02 0.02 30 max 30 max 30max 30max
ppm
--
≤1
≤1
≤1
≤1
%
--
>50
>50
>50
>50
ppm
25
ppm
2500 max 3.13 +/-
100 max 2500 max ≤1.7
100 max 2500 max ≤1.7
100 max 2500 max ≤1.7
100 max 2500 max ≤1.7
%
254+/-2 248+/2 >75 >90
248+/2 >90
248+/2 >90
248+/2 +/-90
%
-3 to -2
-3 to -2
-3 to -2
-3 to -2
gm oc
-0.5 to 1.2
PET films (BOPET) PET calendared sheet, Crisp packaging, Audio-Video tapes, X-ray films, Adhesive tapes, Antistatic packaging Mineral water bottle, Small jars 29
Alcoholic beverage, pharmaceutical product bottle, wide mouth jars Coca-Cola, PepsiCo bottle, APET sheets CSD, Still/sparkling water bottle 20 liter/5 gallon mineral water jar, thick wall performs Fiber preparation Preparation of hot-fill bottle
Safety is the one of most important thing in the industrial plant. Safety should be on the priority for any work we do. Ignoring the safety is increasing the chances of accidents. In IVL persons Dhunseri, a department for safety named as “Fire & Safety Department”. Total ten arethere in theisdepartment. It is intended to help an organization to control occupational health and safety risks. It was developed in response to widespread demand for a recognized standard against which to be certified and assessed, reduce the potential for accidents, aid legislative compliance and improve overall performance. As per the plant operations, any accident should be reported immediately to fire and safety department. Training is given by safety department to the persons working in the plant at different intervals. Safety shoes and helmet is necessary in the plant. Pictorial diagram are 30
placed at various places in the plant regarding safety. Pictorial diagram are easy to understand. The main aim of safety department is ZERO ACCIDENTS. It includes man, material and money protection. Personal protective equipment, also known as PPEs are used by the workers. Different types of PPEs are –
Safety shoes Helmet Heat resistance hand gloves Cut proof hand gloves Electric proof hand gloves Leather hand gloves Multipurpose gas cartridge Gas full face mask Gas half face mask Dust mask Protective glasses for eye protection Self-cleaning breathing apparatus Ear plug
There are various others protective equipment. Using PPE is the best option for prevention from accidents. There are two types of work done in plant: routine work and non-routine work. Routine work is done daily such as loading and unloading of oil, loading of finished product etc. Required safety is enough and doesn’t need inspection from safety department.
( ) is a way of preventing mistakes or defects in manufactured products and avoiding problems when delivering solutions or services to customers. QA is applied to physical products in pre-production to verify what will be made meets specifications and requirements, and during manufacturing production runs by validating lot samples meet specified quality controls. QA is also applied to software to verify that features and functionality meet business objectives, and that code is relatively bug free prior to shipping or releasing new software products and versions.
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At DPL, It committed to customer satisfaction. It shall meet customer needs and expectations by timely delivery of quality products through continual improvement of technology, infrastructure and work environment with innovation and total participation.
QC & QA department is one of the most important department of any organization or industry. standard. QC & QAThis helps to also check the properties of effect running product and maintain the required dept. checks and tests the of new substitute of chemicals in our product. In IVL Dhunseri we follow the SQC (Six sigma quality control) for the best and accurate result of our finished product for our customer, which is the priority of the IVL Dhunseri. By following six sigma quality control we improve the quality of our product upto 99.99%. QAD tests the different properties of every batch of finished PET to maintain the standard. It follows the ASTM (American Standard for Testing and Material) testing standard. Following tests are performed by QC & QA.
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Acid Number of PTA & IPA Sample Determination of Moisture Content in Incoming and In process Sample Determination of particle size of incoming PTA & IPA sample Determination of colour values of incoming material (PTA, IPA, ATA etc.) determination of ash content of incoming sample (raw material and finish PDTS.) Determination of Iron content of Incoming sample like PTA, TPA, MEG, DEG, H3PO4, water sample by UV Spectrometer Determination of percentage UV Transmittance of MEG for all MEG samples received through tankers, ship, in process sample Determination of Acid Number of MEG & DEG Determination of Aldehyde content in MEG tanker/process Determination of DEG in MEG (MEG in process MEG sample) Determination of IV (intrinsic viscosity) of polymer Determination of crystallinity of PET resin of all process samples (precrystallizer, final crystallizer, cooler deduster, reactor, finished product ) Determination of pH in water sample Determination of Carboxyl end group in polymer & base/SSP resin Determination n conductivity & TDS in water sample Determination of free glycol in process column and reflux water
The known quantity of PTA /IPA sample is dissolved in di-methyl formaldehyde and titrated against NaOH Indicator = phenolphthalein Low pH = colourless, . pH- 8 =pink, . pH- 10 =red
Where,
A = NaOH spent for sample B = NaOH spent for blank N = Normality of NaOH
The known quantity of MEG/DEG is dissolved in demineralised water and titrated against aqueous NaOH solution. →
Where, V = volume of 0.02 (N) NaOH spent for sample v = volume of 0.02 (N) NaOH spent for blank N = normality of 0.02 (N) NaOH W= weight of sample in gm Acid no is determined to know the extent of reaction in ES1 & ES2.
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For process sample and finished product (ES-1, ES-2, PP-1, PP-2, Amorphous, SSP resin and finished product) : Ubbelhode viscometer (capillary tube type) The polymer is dissolved in a mixture of phenol and 1,2-dichlorobenzene solvent where upon time of flow is determined in a Ubbelhode viscometer. The relative viscosity is obtained from quotient of the time of flow of the polymer solution (t) and that of pure solvent (t0). As, η
η
η
The relative viscosity is linked with intrinsic viscosity via Bill Meyer’s equationη
η
η
The intrinsic viscosity is defined as the limiting value of the ratio of logarithm of the relative solution viscosity to the concentration, C of the polymer in the solution for C against 0 η
η →
It depends on the solvent, the temperature at which the relative viscosity is determined and on the concentration ‘C’ which is to be shown in gm/lit. In this method of analysis the relative solution viscosity is determined at concentration C is equal to 0.5 up to 0.65 gm/lit.
Determination of relative viscosityWhere, t1 = mean time of flow of polymer, sec to = mean time of flow of solvent, sec
Factor ‘F’ is available from standard table
Density of polymer chips is measured with a floating method by comparison in a density gradient column with an inert and wetting liquid. From the resulting density crystallinity can be calculated using density values for totally crystalline PTA & for totally amorphous PTA from literature.
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A reliable and efficient performance of utility plants is of high importance in order to save costs in the industrial production processes . IVL Dhunseri ensures that the utility plant is optimally adapted to match their process’ steam and water consumption profile. It encompasses following components; 1. Water treatment plant 2. Air compressor 3. Cooling tower 4. Effluent Treatment Plant 5. Nitrogen storage 6. Chilled water In the following discussion we have describe the water treatment plant, effluent treatment plant and cooling tower in details.
The water that is treated over here is supplied by Haldia Development Authority (HDA). This water is stored in two sumps where sodium hypochlorite (NaOCl) is dosed to remove the algae & bacteria present in the water. Then the water is pumped and it enters a multicapacity sand bed filter. Before entering the filter bed, FeSO4 is dosed into it which acts as a coagulant and flocculation takes place. It also helps in precipitation of calcium bicarbonate salts. All the precipitated calcium salts and the flocs formed are then filtered in the filter bed. The outlet of the filter bed contains reduced calcium and less TSS (Total 36
suspended solids). Then the filtrate enters the activated carbon filter where the excess chlorine which was unutilized is removed. This filter bed also removes any colour or odour if present in water. Thereafter the filtrate goes through a pipeline where Sodium hexametaphosphate (SHMP) AND Sodium metabisulphite (SMBS) are added. SHMP acts as an antiscalant whereas SMBS removes the chlorine, if any, present in the system which is not removed by activated carbon filter. Here the chlorine should be maintained at 0 ppm level or else the membrane (which is used in Reversed Osmosis) may get oxidize completely. From here the activated filter the goes to a micro filter for further purification. From here the line gets divided into two sections1. One of which goes to the drinking water supply after chlorine dosing. 2. another goes to the reverse osmosis(R.O.) columns for its softening R.O. columns contain layers of semi permeable membranes usually made of cellulose acetate or polyamides. The hard water after passing through the membranes is separated into two parts, one part which has greater flow rate and lower conc. is the desired soft water and is called the permeate, the other part called the rejecters has lower flow rates but higher conc. of salts. One part of the soft water is stored in soft water storage tank used as make up water in cooling tower. And another part goes to the demineralization plant (D.M plant). Here the soft water having lesser TDS & TSS is then passed through a degasser tower which is nothing but a packed tower where the carbonate load is reduced and then the water is send to a mixed bed (containing both cation and anion exchange resins) . Dematerialized water used in cutting section as mentioned earlier. The D.M. water produced meets the following criteria: 1. pH=6.5~7.0 2. Conductivity<0.2 microsemens/cm 3. Silica<0.02 ppm 4. Hardness=0.0 This water is stored in the D.M. water storage tank.
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The heated water from the plant returning to the top of the cooling tower (hot water deck) through a header. From this the water is distributed to individual cells through the distributor valves. The valve is throttled accordingly to get constant flow in each cell. The cooling tower is an Induced draft cross flow one where the water from individual cells are divided into fine droplets use in distributor nozzles and GRP made ‘V’ supports and the air is sucked from the sides of the tower using four fans located at the top of the tower. Here both heat and mass transfer takes place simultaneously, the temperature of the water is cooled down from 380C to 330C. Four types of losses generally occur here— 1. Evaporation loss 2. Windage loss 3. Drift loss 4. Blow down 38
Two entrainment catchers are there in each cell to reduce drift loss and mainly the blow down loss is taken care of by adding soft water as and when required.
ETP (Effluent Treatment Plant) is a process design for treating the industrial waste water for its reuse or safe disposal to the environment.
• To clean industry effluent and recycle it for further use. • To reduce the usage of fresh/potable water in Industries. • To cut expenditure on water procurement. • To meet the Standards for emission or discharge of environmental pollutants from various Industries set by the Government and avoid hefty penalties. • To safeguard environment against pollution and contribute in sustainable development.
Physical
Chemical
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Biological
Different parts in ETP:
Screen chamber is inlet for the ETP which is used as a storage tank for the effluent water coming out from the plant. The pH at ETP inlet is between 6.5-8.0. The temperature of the effluent water at inlet is about 60 ◦c.
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The mixed effluent from screen chamber is pumped with the help of FRP Pumps to oil and grease trap. Main function of this chamber is to remove the oil and grease from effluent water. To trap the oil and grease, we use a conveying system with 2 motors and a leather belt. When motors start rotating grease and oil from water gets trap with the belt and water moves forward towards the equalization tank.
The water streams coming continuously shall be collected in the equalization tank. An air grid is provided in this tank to blow air with the help of air blower. This is to keep the solids in suspension and avoid settling in this tank. The inlet pH of the effluent is expected to be in the range of 7.5~8.0. The effluent flows to a equalisation tank where the pH is indicated by a pH indicator and liquid (base) is dosed to maintain pH which is mainly NaOH. Purpose of this tank is to maintain certain alkalinity level in the effluent. The mixed effluent from equalization tank is pumped with the help of FRP pumps to conventional aeration tank. Depending on the raw effluent characteristics nutrient dosing will be done for best microbial development.
The effluent is pumped from the equalization tank into conventional aeration tank (CAT). The effluent is then pumped to a CAT for degradation of organic matter by anaerobic bacteria where major portion of BOD& COD is reduced. The CAT works on the principle of degradation of organic matter within sludge bed situated at the bottom of the reactor. The anaerobic bacteria present in sludge bed come in the bottom of the tank. The Anaerobic bacteria present in the sludge bed come in intimate contact with the organics, which are reduced to low molecular fatty acids. These fatty acids are then converted to simpler end products such as CO2, CH4 gas, H2O molecules and more bacteria. Urea and DSP are added to effluent as a food to anaerobic bacteria. The CAT consists of3 agitators for mixing up the effluent. The pH of sludge in CAT is about 7.8-8.8. The sludge and water from the CAT is then pumped to
The sludge and water from the CAT is pumped to the clarifier A. Clarifier A consists of a single agitators which helps in slowly agitating the effluent. In the clarifier A, sludge being heavy gets settle down in the bottom and water stores on the upper portion of clarifier A. Here the sludge which is in the suspended form settled down &recirculated to aeration tank. If the MLSS of the aeration tank increases beyond limits, then the settled sludge is thrown out of the system with the help of PUMP. The sludge from clarifier A is recycled by pumping it to the CAT. The excess amount of sludge is pumped to for further treatment. The water from clarifier A is pumped to The pH on the outlet of clarifier A is between 7.0-8.0.
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. The effluent treated, then is pumped to EAT wherein further degradation of COD/BOD takes place anaerobically in a similar fashion as that of CAT. The EAT consists of 2 agitators for mixing. The Ph of sludge in EAT is about 7.8-8.8. The sludge and water from the EAT is then pumped to
The sludge and water from the EAT is pumped to the clarifier B. Clarifier B consists of a single agitator which helps in slowly agitating the effluent. In the clarifier B, sludge being heavy gets settle down in the bottom and water stores on the upper portion of clarifier B. Here the sludge which is in the suspended form settled down &recirculated to aeration tank. If the MLSS of the aeration tank increases beyond limits, then the settled sludge is thrown out of the system with the help of PUMP. The sludge from clarifier B is recycled by pumping it to the EAT. The excess amount of sludge is pumped to for further treatment. The water from clarifier B is pumped to The pH on the outlet of clarifier A is between 7.0-8.0.
Flash mixer is temporary storage type tank which is used for storing water coming out from Clarifier B. The water from the Flash mixer is pumped to .
.the In upper the Flocculator., being Here heavythe gets settlewhich down is inin the bottom and water stores on portion of sludge Flocculator. sludge the suspended form settled down & pumped to . The water from Flocculator. is pumped to The pH on the outlet of Flocculator is between 7.0-8.0.
This is outlet for the ETP from where we get purified water. It consists of filter with a membrane which separates the water from sludge Purified water can be used further in processing.
SLUDGE THICKNER is a storage tank for the sludge generated from Clarifier A, Clarifier B &Flocculator. Sludge is transferred to the with the help of pump.
The sludge generated from Clarifier A, Clarifier B & Flocculator would be taken to . The objective of filter press is remove moisture from sludge. Water/moisture is removed from the sludge and converted into cake form.
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In Coal Heater the heat created and the ash discharge line is shown in the following flowsheet
In this coal heater as a media Therminol 66 is used. Here first present a fluidized bed of sand. At first Flue gas is supplied from the Forced Draft fan to the bed and from the upper portion of the bed coal grinds has been sprayed and by the help of matches’ first time fire is flow through the bed. By the help of coal, the fire is continuously flow. Here sand is used for equal distribution of the temperature and it also contains the heat. In bed temperature remains 306.7 oC. The temperature of Therminol 66 maintained 330⁰C. The flow of the oil is maintained at 850-900m3/hr and the pressure is 45kg/m2. In the bed there is four section, this is because to maintain the fire and the heat. This four section have total 1500 nozzles each have 375 nozzles and each nozzle have 12 holes for the flue gas pass. Here level is maintained from 420 -460 mm wc. The inlet pressure is 11.5kg/cm2 and the outlet pressure is 8.5kg/cm2 approximately.
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From the bed the Therminol oil go to the Heat Exchanger and here present coils inside the heat exchanger and 8 coils are present those coils are made up of copper. When the oil come out from the furnace it has low temperature and in the heat exchanger its temperature increases near about 20oC i.e. 320oC.In the bottom of the heat exchanger present a fly ash settling chamber and here fly ash is collected and from here by Slot Chain Conveyer which have some plate type setting and by this ash is send to the Silo where water is sprayed to the ash so that it will not fly
in the atmosphere. Here two motors are also used. In Heat Exchanger inlet pressure is 8.5kg/cm2 and the outlet pressure is 6.9kg/cm2 approximately.
From the Heat Exchanger, the heated oil then goes to the membrane panel which is situated at the top of the furnace and this membrane is heated by the Furnace, Coils, Heat Exchanger and here temperature becomes 324oC and from here heat went to the plant and stored to the expansion tanks.
The main function of the boiler is to heat water and produce steam. Here the shell and tube type boiler is used. From the shell side water is passed and from the tube side flue gas is passed. Here water became steam continuously and for this water is supplied from the water tank. Here temperature remain 120^oC.
From the Boiler the flue gas goes to the air pre heater and there the flue gas temperature became 33^oC. The main purpose of the APH is to recover the heat from the boiler flue gas which increase the thermal efficiency of the boiler by reducing the useful heat lost in the flue gas.
From the APH the flue gas now went to the Bag Filter or if the Bag Filter does not work then went to the Cyclo Max. In bag Filter coal dust is collected from flue gas and before bag Filter there is a Inlet cum bypass dumper valve is used. After that there is an ID (Induced Draft fan) which consume air.
After the Bag Filter the ash is send to the chimney, and from that the extra ash is send to the atmosphere.
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Normally the heating is done by the help of coal heater but FO heaters are kept in standby. There are two heaters and there are 3 FO pumps working 2 at a time and 1 is kept in standby. Each FO heater has a burner assembly mounted on it, the burner assembly consist of the following thingsCamp A cylindrical gun FO supply line FO return line Two bypass line Oil regulator Flame sensor Servo motor
Each HTM heater has five coils and each coil has two turns through which the HTM which has lost some of its heat in the process (temp around 280-degree C, pressures around 2.5 bars) is circulated. FO coming from FO yard at3.5bar pressure through pipelines enters a separator and pumped to the top of the heater using screw pumps at around 20 bar pressure and by means FO guns atomization takes place. Otherwise if the droplet of FO is large, soon deposition and 45
incomplete combustion might occur. The flow is concerned by means of FO supply line. When not in operation these twos.
valves are closed while another ring is opened which allows a bypass., the FO to circulate in a closed loop. The supply of air is maintained by the help of camp. Once the LPG is sprayed by means of separate gun and due to high voltage (11000 volts) applied across the electrode adjacent to the FO gun and the spark is produced called pilot flame, the FO supply line is opened and FO is allowed in. The fuel is burned by the help of this flame. The temp of the heater is controlled by controlling the servo motor which control flow of both air and oil at minimum opining (12%) the rate is 350 kg/hr. and with the help of diffuser plate which is used for the movement of the gun and situated just below the burner which is situated below gun. In this process HTM gets heated up and is recirculate to the plant. A flame sensor is used to sense the flame of the heater. The HTM after heating attains a temp of around 330 C and pressure of 6 bars and sent to the process section and also the heated gasses are sent to the air preheater where it gets mixed with the atmospheric air coming from the blower and heat it and the heated air is again sent to the heater and the remaining is sent to the chimney to dispose to the atmosphere.
Model- TP-80HT Output-80, 00,000kcal/hr. or 4.3 MW Fuel- FO (furnace oil) Max temperature- 330 0c
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With IVL Dhunseri’s achievement of a high degree of self-reliance in polymer IVL Dhunseri technology, is poised for a brightinfuture. All outproduction, action have value been taken for capacity augmentation, increase polymeric addition, cost reduction for obtaining higher margins and improving productivity. All environment friendly projects with latest technology are being incorporated to meet the challenge posed by other technologies. IVL Dhunseri will continue to play a significant role in meeting the vital needs of polymeric products in the country and abroad.
(CUTTER-DEMINERALISED WATER SYSTEM)
In cutter section, we know that De mineral water (DM WATER) is used to withdraw heat from the polymer formed, so that it may crystallize and we can get crystallized product but in the way of cooling the polymer, the DM water gets heated and we have to withdraw this extra heat by plate type heat exchanger in order to maintain the cycle. For this reason, we use cooling water. We must determine number of plates and outlet target temperature of DM water less than 34 c.
GIVEN DATAPOLYMER: flow rate(m)=33541.56 kg/hour Specific heat capacity=2.299kj/kg◦c 47
Polymer inlet temperature in cutter: 286.3◦c Polymer outlet temperature in cutter: 40◦c Chilled water flow rate(m)=1000 m3/hr Chilled water inlet temperature=11.5◦c Cooling water outlet temperature=15.8◦c DM water flow rate(m)=169 m3/hr DM water inlet temperature=42◦c DM water outlet temperature=34◦c (take co-current process)
OBJECTIVES:
1.NUMBER OF PLATES USED-to be determined. Data taken:
Density of water at 42c=989.1kg/m3 Density of water at 34c=995kg/m3 Heat capacity of water at 42◦c=4.18kj/kg k Heat capacity of water at 34◦c=4.178kj/kg k Thermal conductivity of water=0.58w/m k
Calculation
Polymer heat load=m*Cp*∆T =9.3171x2.299x246.23 =5274.249kW
There is a heat loss of 10% to the surrounding,
Therefore, heat load to the heat exchanger=4746.824kw 48
Heat liberated by polymer shall be accepted by DM water employed. Therefore, Q=MCp(dT) 4746.824 = 188 x 989.1 x 4.179xdT dT= 21.9044◦c DM water Outlet temperature from cutter = 56.1◦c This is the temperature of DM water inlet flow in heat exchanger 1. Let the intermediate temperature between the heat exchangers be 42◦c. Now, LMTD= (42-11.5) – (34-15.8)/ ln ((42-11.5)/(34-15.8)) = 23.82◦c The heat taken up by the second exchanger = heat taken up by the polymer- heat taken up by the second exchanger Heat taken up by the second exchanger = 4746.824 – 3022 =1724.824 kW Assume overall heat transfer coefficient=5000 w/m2◦c (for water-water system & no phase change) Q=U*A*LMTD Area available, 172.824x1000=5000xAx23.823 A=14.480 m2 Area of a single plate=(0.4344)m2 Number of plate= 34 So, no of channel=(34-1)/2=17 (approx)
For DM water : Let total flow rate loss in the first heat exchanger be 10% of the total flow. Therefore, Channel flow rate=169 m^3/hr Hence channel velocity, =Q/A = (169/3600x3x0.48x17)x1000 m/sec 49
=1.9176 m/s Re=989.1*1.9176*3*10^(-3)/0.5102*10^(-3) =11152.72 Pr=0.5102*10^(-3)*4.179*1000/0.58 =3.6787 Nu=0.023*(11152.72)0.8*(3.6787).3 =58.79 Therefore, hdm= 11366.0W w/m2◦c
For COOLING WATER : Flow rate=1000 m3/hr Velocity= 1000/0.001*3*3600*0.48*17 =11.347 m/sec Re= 998.2*11.347*3*10^(-3)/0.7438*10^(-3) =15227.985 Pr=0.7488*10^(-3)*4.178*1000/0.58 =5.61 Nu=0.023*(15227.985)0.8*(5.61)0.4 =101.722 Therefore, hc=19666.25 w/m◦c Thickness of plate=3mm & thermal conductivity of Stainless Steel=15.2 w/m◦c CALCULATION OF HEAT TRANSFER COFFICIENT: (1/U) = (1/19666.25) + (3*10^(-3)/15.2)+ 1/11366.06)
U=2974.5094 w/m2◦c (This value of overall heat transfer coefficient is a bit lower than the assumption made) Area available = (1724.824*1000)/ (23.823 * 2974.5094) =24.34 m2 50
Area of a single plate= 0.4344 m2 Number of plates= 24.34/0.4344= 55.32=56 (approx)
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