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Internship at ITTEHAD CHEMICALS LTD An internship report submitted in Partial satisfaction of the requirements For the degree of Bachelor of Science in Chemical Engineering By Gulam Mujtaba Mufti FA-09-BEC-107-A Comsatas Institute of Information and Technology

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Internship at ITTEHAD CHEMICALS LTD An internship report submitted in Partial satisfaction of the requirements

For the degree of

Bachelor of Science in Chemical Engineering By Gulam Mujtaba Mufti FA-09-BEC-107-A

Comsatas Institute of Information and Technology Lahore.

Internship at ITTEHAD CHEMICALS LTD An internship report submitted in Partial satisfaction of the requirements

For the degree of

Bachelor of Science in Chemical Engineering By Gulam Mujtaba Mufti FA-09-BEC-107-A

Comsatas Institute of Information and Technology Lahore.

DEPARTMENT OF CHEMICAL ENGINEERING TO WHOM IT MAY CONCERN

Dear Sir, Submitted for your review is the report of my four week internship at Ittehad Chemicals Limited, during August 2012. It is hereby declared that the report is compiled in long report format, as per the guidelines and is based upon the literature review; plant manuals and standard operating procedures; process flow diagrams and sharing and learning from management and staff of the company It is anticipated that response will be reflected.

Dated:August 07, 2012

ACKNOWLEDGEMENTSInternship is a basic necessity and a must requirement of Chemical Engineering. With blessing of Allah, we got a chance to complete our internship in Ittehad Chemicals Limited. The people at ICL are very kind, friendly and corporative. We have gained a lot of professional experience, skills and knowledge under the assistance of chemical experts. First of all we would like to thank General Manager Plant & H.R Manager who gave us opportunity to do internship in ICL. We are also very thankful to all the management and staff of Ittehad Chemical Limited especially unit managers, staff engineers, learning & development center , supervisors, operators and others for all their utmost help, guidance and time.

ABSTRACTThis report consists of the brief over view of ICL, its major products, their manufacturing processes. Manufacturing processes are further elaborated with the help of figures. In fact ICL is a leading chemicals manufacturers in Pakistan.

Report OutlineIntroduction Chapter#01.. The I.E.M Brine Unit Chapter#02.. The D.S.A Brine Unit

Chapter#03.. The Cell Rooms

Chapter#04.. The I.E.M Cell Room

Chapter#05.. Hydrochloric Acid Unit

Chapter#06.. Sodium Hypochlorite Unit

INDUSTRY PROFILEIttehad Chemicals Limited (ICL) was established in 1962 under the name of United Chemicals by a private entrepreneur. ICL was commissioned in the year 1964 with an installed capacity of 40 MT/day of Caustic Soda. The initial plant was set up by M/S Oronzio Denora of Italy. The factory is strategically located on the 19th/20th Kilometer of GT Road and spread over an area of 106 acres. It is approachable from the Lahore-Islamabad Motorway as well as from the main city of Lahore, being less than an hour drive. The place is known as Kala Shah Kaku, an industrial site which has seen the growth of industries over the past decades stretching up and beyond Gujranwala along the G.T Road. Apparently, Kala Shah Kaku and its neighboring vicinities have both gained tremendous importance and become a hub of commercial, economic and educational activities. As industrialization flourished over the years, a large number of small townships also mushroomed in and around the vicinity due to availability of livelihood to the local residents at their doorsteps. Under the Economic Reforms Order, United Chemicals was nationalized in 1971 along with other industries of the country and renamed as Ittehad Chemicals. It was initially managed by the Board of Industrial Management and thereafter the Federal Chemicals & Ceramics Corporation Ltd under the Ministry of Production, Govt. of Pakistan. During the state enterprise period its production capacity was raised by another 90 tons/day during the year 1984-85. The factory

was ultimately denationalized in 1995 by the Privatization Commission Govt. of Pakistan. It was acquired by the Chemi Group of Industries, a Karachi based dynamic entrepreneurial group. The new management immediately undertook the task of refurbishing the factory, its infrastructure, and updating its production line to improve efficiency and capacity.

MissionWe work for our customers to provide a trusted and reliable source of chemical products. Hence, through constant innovation and research we pride ourselves on our unrelentless drive to continuously add-value to our stakeholders, employees, and customers. We strive for sustainable growth in harmony with our environment and suppliers to foster a cordial and mutual relationship

VisionTo be the first choice of preference by customers looking for premium quality chemical products. We aspire to be a trend setter in our industry and always look to the future with courage and a commitment to excellence in all our practices

Chapter# 01

PROCESS REPORT ON I.E.M BRINE UNIT

PROCESS REPORT ON I.E.M BRINE UNIT:I.E.M brine unit provides feed of brine solution to ion exchange membrane cell rooms. The brine solution feed must be ultra pure. The ideal conentration of brine is 280g/L. following are the main comppnents of I.E.M brine unit. 1. Saturator 2. Purifier 3. Settler 4. Primary and secondary filters 5. Ion exchange unit

1. Saturator: It consists of large storage of rock salt. At the rock salt, depleted and dechlorinated brine, also called Anolte is showered in order to concentrate it. The anolite is at a temperature of 65-70 C. the brine solution is stored in three pits from where it is sent to first purifier 2. Purifier: Solution of barium carbonate in which some quantity of hydrochloric acid has been added, is introduced into first purifier. Capacity of first purifier is 70 m3. Excess carbonate

are maintained in the solution to ensure removal of sulphate ion. Sludge formed is periodically removed from bottom of the first purifier. 3. Settler: It has a capacity of 100 m3. Brine overflows from settler after settling. A scraper is also installed in the center, near the bottom of the settler to puch the sludge settled, towards the bottom of the tank where an automatic gate valve open for 15 seconds after every 15 minutes. From the settler, the brine moves to a storage tank. Settler is made of mild steel and coated with a type of resin which is corrosion resistant. 4. Primary and Secondary Filters: From settler, the brine moves to a series of filters where five different layers of pebbles are used to filter the brine solution. The layer at the top is of anthracite and remaining layers are of pebbles whose size increases from top to bottom. 5. Ion Exchange Unit: From secondary filters, brine is transferred to ion exchange unit, where an ion exchange resin of general formula R-Na2 is used to completely remove all impurties out of it. The purifies brine is then sent to I.E.M cell room.

Chapter#02

PROCESS REPORT ON D.S.A BRINE UNIT

PROCESS REPORT ON D.S.A BRINE UNIT D.S.A brine unit provides brine to D.S.A cell rooms. The purity level of brine solution required here is not that much high as for I.E.M cell room. Thats why lesser purifiers are installed in this unit. Another distinguishing feature of the unit is that brine is de chlorinated in this unit as opposed to I.E.M brine unit. The unit consists of following sub-units: 1. Dechlorination unit 2. Saturator 3. Purifier 4. Settler 5. Sand filters 1. Dechlorination unit: Depleted brine from D.S.A cell room is received in a tank marked as 2D10. The PH of incoming brine is 4. Here hydrochloric acid is injected into the tank which releaseschlorine throughcommon ion effect and PH is reduced to 2 due to the acid injected.To improve the PH of brine solution, caustic solution is injected in line, before introduction to the tanks marked as 2D13A and 2D13B. the PH increases to 8-9. The dechlorinated brine is sent to saturator. In dechlorination unit, the chlorine contents in brine solution are reduced to 7.1 ppm 2. Saturator:

It consists of large storage of rock salt. At the rock salt, depleted and dechlorinated brine, also called Anolte is showered in order to concentrate it. The anolite is at a temperature of 65-70 C. the brine solution is stored in three pits from where it is sent to first purifier. 3. Purifier: Solution of barium carbonate in which some quantity of hydrochloric acid has been added, is introduced into first purifier. Capacity of first purifier is 70 m3. Excess carbonate are maintained in the solution to ensure removal of sulphate ion. Sludge formed is periodically removed from bottom of the first purifier.Overflow from first purifier goes to second purifier where caustic solution is added into it. 4. Settler: It has a capacity of 2300 m3. Brine overflows from settler after settling. A scraper is also installed in the center, near the bottom of the settler to puch the sludge settled, towards the bottom of the tank where an automatic gate valve open for 15 seconds after every 15 minutes. 5. Primary and Secondary Filters: From settler, the brine moves to a series of filters where five different layers of pebbles are used to filter the brine solution. The layer at the top is of anthracite and remaining layers are of pebbles whose size increases from top to bottom.After filtration, the brine is sent to a temporary storage marked as 2D6.

Chapter#03

PROCESS REPORT ON The Cell Rooms

PROCESS REPORT ON CELL ROOMS There are two cell rooms at Ittehad chemicals. 1. Northern Cell Room 2. Southern Cell Room Northern cell room have thirty two mercury cells also called as Denoras cell. In addition to the main electrolytic cell , the cell room has following components. 1. Decomposer 2. Circulating tray

PROCESS DETAILS: Brine is introduced at a concentration of 295-300g/L and a temperature of 62 C at a flow rate of 4-5 m3/h for every cell. Mercury is introduced from mercury circulation tray. Sodium mercury amalgam is taken out from the opposite side and sent to decomposer. Feed water is introduced into the decomposer. Caustic solution is sent to receiver tank for caustic. From the tank, caustic solution is sent to main caustic storage tank after passing through a filter having porous tubes of graphite. The hydrogen formed is passed through hydrogen cooler and then sent to the furnaces for the production of hydrochloric acid. In S.C.R, separate hydrogen coolers have been provided for individual cells while in N.C.R, large hydrogen cooler have been provided which cools the hydrogen collected from the whole cell room. Chlorine released is also sent to the furnaces after washing it with water.

Chapter#04

PROCESS REPORT ON I.E.M CELL ROOMS

PROCESS REPORT ON I.E.M CELL ROOM Ion Exchange Membrane technology is the latest technique of production of caustic soda. The technique uses semi- permeable membranes. The cells have been imported from USA. Ion exchange membrane technology is safer than mercury cells. In Ittehad Chemical Limited, we have total forty cells in I.E.M. cell room. The unit can be divided into following sub-units: 1. Brine feed unit 2. Caustic unite 3. I.E.M. unite 4. Dechlorination unit Brief discussion of the above mentioned sub-unite is as follows: 1. Brine Feed unit: Ultra pure brine from I.E.M brine unit is received in UP brine tank which is at ground level. From here, brine is transferred to two overhead tanks. In case of these overhead tanks, brine is transferred to UP brine tank no.1 and if it also overflows, than brine is sent to UP brine tank no.2. From overhead tanks, the brine is fed to the cells in the cell room. 2. Caustic Unit: The imported and the only major component of caustic unit is Caustic Circulation Tank [C.C.T].Product from the cell room [i.e.31% caustic solution] is received in this C.C.T. At the same time, in case of malfunctioning of any cell, the drained caustic is also

transferred to this tank. Moreover hydrogen gas formed during electrolysis is also passed through this tank before sending to hydrochloric acid furnaces. 3. I.E.M.CELLS: The cells are not only the most important but also the most expensive component of cell room. CONSTRACTION: A cell consists of following parts: 1. Bulk heads 2. Bulk head insulators 3. Inter cell spacers 4. Current distributors 5. Membranes 6. Electrode plates Each cathode is made of nickel and each anode is made of titanium. Current distributors are made of copper with mesh of nickel sticking over it. WORKING/CHEMICAL REACTIONS: Brine is injected from bottom right side of the cell and caustic (28%) is injected from bottom left side of the tank. While product i.e. 31% caustic is recovered from top right side of the tank and hydrogen is also recovered from the same side. While depleted brine, also called anolite is recovered from top left side of the cell and chlorine is also recovered from the same side. Drain lines are provided at bottom side while overflow lines are provided at top side of the tank, both for brine and caustic.

Hence chlorine is collected from anode and hydrogen and caustic of required concentration i.e. 31% is collected at cathode. Each cell consumes approximately 9 volts. From power plant 13Kv are received and stepped down to 370 volts. PURGING OPERATION: Air is used for purging of hydrogen from the whole system and /or the cell when they are taken out of the circuit. Nitrogen is used only when chlorine is required to be taken out of the whole system. DECHLORINATION UNIT: Depleted brine is sent to depleted brine tank at ground level, from where is pumped to an overhead dechlorination tower. The tower is randomly packed with rushing rings. Brine enters from top & both dechlorinated brine as well as chlorine is removed from bottom of the tower from two different outlets at same level. The chlorine is sent to a heat exchanger at a higher level where its temperature reduses from 89 c to approximately 50c.This chlorine is pumped with the help of liquid ring type rotary compressor & pass through deleted brine tank & finally sent to hydrochloric acid furnaces.The liquid used to lubricate the pump is also sent to depleted brine tank. The dechlorinated brine is sent to dechlorinated brine tank, from where it is sent to saturators of I.E.M brine unit.

Chapter#05

PROCESS REPORT ON HYDROCHLORIC ACID UNIT

Process Description: Hydrochloric acid plant utilizes the gases produced as the byproducts of I.E.M. cell room ,northern cell room and southern cell room. These gases are hydrogen and chlorine. There are 12 furnaces. The furnaces may be top fired or bottom fired and may be operating under pressure or under suction.

1.BOTTOM FIRED UNDER PRESSURE FURNACES CONSTRUCTION BURNING CHAMBER: The lower portion of the furnace is called as capsule. This contains the burner in which inlets for hydrogen and chlorine is provided. Two sight glasses are provided in it. A graphite shell is provided to circulate cooling water to cool the shell. There is a purging line for the introduction of nitrogen into the hydrogen line during shutdown operation. A condensate line is also provided for the discharge of water condensed in the burner.

Absorber Absorber contains shells of graphite in which tubes have been provided for interaction of gas and weak acid. The shells have been provided with a central passage which forms a central channel. Moreover the outer side of shell is provided with notch type projections which are

projected inward. These projections allow efficient circulation of cooling water. there is a burst plate at the top of the furnace which is a safety measure to avoid any loss to the furnace incase of increase pressure.

TAIL TOWER Tail tower is still a separate component in new models of furnaces as well. Tail tower is randomly packed with rashing rings. In some cases, cooling water is provided in the lower portion of the tower to increase absorption of gases in feed water.

WORKING OF FURNACES FIRING OPERATION Furnace is fired with a small line of hydrogen called Lance. Lance is inserted into the capsule through a sight glass and hydrogen supply is started at very slow rate. When hydrogen catches fire than lance is removed but the sight glass is not closed; to provide oxygen for its burning. Now supply of chlorine gas is started which starts burning with hydrogen. When complete combustion of hydrogen with chlorine starts(white flame) the sight glass is closed and furnace starts its operation. WORKING MECHANISM Hydrogen chloride gas formed rises through the central channel to the top of furnace. Here it mixes with weak acid and flows down

the tubes along with the acid. Concentrated acid is collected in a collection in a collection plate from where it is sent to storage tanks while unabsorbed gases are sent to tail tower for further absorption. BOTTOM FIRED UNDER SUCTION FURNACES The major components of furnace are: 1. Chamber 2. Joint piece 3. Precooler 4. Absorber 5. Tail tower 6. Scrubber CHAMBER The chamber has circular hollow cylindrical sections or elements of graphite which are fixed in a mild steel shell. it is also provided with a cooling water chest. At the top, there is a crown for equal distribution of water in all sides. Below the crown is a burst plate made of graphite. It lifts to some extent after which it will burst. Hydrogen and chlorine are fed in the same manner as in case of the furnace which is bottom fired under pressure. Temperature of the flame is 1800 C . Cooling water is showered with the help of the crown which equally distributes it in al sides and finally collected at the bottom and sent to water cooling unit.

JOINT PIECE

Joint piece is made of graphite. It is joint between chamber and pre cooler. it is also cooled by cooling water which is also distributed with the help of a rectangular crown as opposed to the chamber in which water was distributed by circular crown.

PRECOOLER Precooler ha 109 graphite tubes and receives gas at a temperature of 250300 C and exits it at a temperature lo enough to allow its absorption in feed water.

ABSORBER Absorber is also a vertical column having shell and tube arrangement consisting of 77 tubes of graphite in which gas and weak acid flow co currently. Concentrated acid is sent to storage tanks while unabsorbed gases also leave from bottom and are sent to tail tower.

TAIL TOWER Tail tower is, ceramic made rashing packed column where unabsorbed gases are coming from bottom and feed water is

showered from the top. Weak acid formed is sent to absorber for further concentration. SCRUBBER Unabsorbed gases from tail tower are from scrubber. scrubber is also rashing ring packed section where industrial water I showered at different levels to maximize the absorption of gases. The weak acid formed is drained. Un absorbed gases from scrubber are exhausted to atmosphere with the help of an exhausted. TOP FIRE UNER PREURE FURNACE CONTRUCTION AND WORKING The furnace consists of a tall straight burning chamber in which section if graphite have been fie one above another. Each of this graphite section ha 1224 to 10 tube in it. gases are burned at the top in the similar manner an fame/burnt gases move downward along with weak acid coming from tail tower an concentrate acid is recovered from bottom of the furnace while unabsorbed gases are sent to tail tower. Here further absorption of thee gases with the feed water take place. Weak acid formed I transferred to burning/ absorption chamber an still unabsorbed gases are exhausted to atmosphere.

Chapter#06

PROCESS REPORT ON SODIUM HYPOCHORITE UNIT

PROCESS DISCRIPTION Caustic solution (30%) is received from IEM cell rooms in the storage tanks. It I then diluted to 23%. A batch of 40 ton of dilute caustic solution I prepare an transferred to the reactor. Reactor acts as an storage tank as well as circulating tank for both caustic solution an sodium hypochlorite solution formed. Caustic solution is sent to the cooer. Cooler is shell an tube type of cooer having titanium tubes in it . After cooling, it is sent to absorber where chlorine is absorbed in it. Chlorine is coming in this unit, either from hydrochloric acid pant or chlorine compression room. The circulation of sodium hypochlorite formed is continue until this solution as only 1% caustic in it. Moreover caustic hypochlorite solution formed must have 19.8% chlorine. The temperature during reaction must be maintained at 25-30 C. after the completion of process, the hypochlorite sold at 15 C.