Dhaka Hide and Skins Ltd.

IntroductionA technology is considered alive so long as it changes its shape with time. The tremendous changes, which have taken place, recently are the leather manufacturing process indicates that the leather industry is not at a dead industry. This leather sector has an abundant prospect if this change in technology goes on.We have a rich world recognize syllabus about our subject and we also have well equipped laboratory facilities. But for the real knowledge the industrial training have no alternatives. In an industry we can realize the technology very briefly and we can introduce with the technology in much production.In industry we can get a vast knowledge about the process control, quality control, product planning maintenance, assessment which qualities are badly require for a good technologist.We learn the constructional details of different machines and use a little of them in practice. But in industry we can learn the practical uses vastly. Which helps us to select a correct type of machine necessary for their production and we get a clear concept about the advantages and disadvantages of different machines for a particular operation?A good technologist should have the knowledge to gain a bridge between the employer and the employee to run the industry smoothly. And this knowledge we can only achieve when we will visit an industry and work with the employees.Thus industrial training is an inseparable important part of technological education.Aim of the Training

To get idea about the vast commercial production. To be acquainted with factory environment. To observe the plan layout of the industry. To have a closer look at each and every step of leather manufacturing. To correlate between institutional and industrial working techniques and procedures. To observe the management system. To have a concept on production plan, production cost. To lookout some update technology. To know about waste utilization

Industry at a Glance:DHAKA HIDE AND SKINS LTD.147, Hazaribag Tannery Area.Mr. M.A. Rashid Bhuiyan Managing Director An Overview:Our country Bangladesh is a developing small country in South Asia. A lion share of GDP is contributed by leather sector in this country, and “DHAKA HIDE & SKINS" is one of the pioneer in leather processing & exporting industry in this sector.From a moderate start at 1978, with few struggling initial years, DHAKA HIDE & SKINS never look back D.H.S is now one of the largest and prosperous leather industries in Bangladesh. Their experience allows them to have the best technology and technique in leather processing as they have installed world’s most modern and sophisticated machines in their production floor.

They have the decades of enviable experience in exporting drum dyed crust and finished leathers of super qualify to countries like Japan, Korea, Taiwan, Australia, Hong-Kong, Italy, Germany, France, Spain, China, United Kingdom, United States, Brazil, Russia & Philippines.Several national awards as a best company for export, indicates the nations recognition and gratitude to the effort of DHAKA HIDE & SKINS. For brining repute to country as an exporter of quality leather and leather goods, along with that they make good contribution in employment generation. Thus DHAKA HIDE & SKINS. Serves the nation by earning a lot of foreign currency very praiseworthily to lead the country to development.DESCRIPTION OF THE INDUSTRY1. Name of the industry : DHAKA HIDE AND SKINS LTD.2. Location: Dhaka Hide And Skins Ltd. (Unit-1)147, Hazaribag Tannery AreaDhaka - 1209,Bangladesh.Dhaka Hide And Skins Ltd. (Unit-2&3)36, Kalunagar, Hazaribag, Dhaka-12093. Establishment: 19784. Modernized: 19905. Type of industry: Private Leather Industry.6. Tannery InfrastructureUnit-1: Two storiedUnit-2: Multi storied7. Machineries a. Wet Blue Section Drum: It is mainly used in beam house and retanning operation.Fleshing Machine: b. Crust Section: Samming Machine: Paddle: Chrome Recovery Plant:

8.Tannery Manpower InformationChairman: Most. Feroza Begum M.D.: M.A. Rashid Bhuiyan Director: Md. Rokon Bhuiyan D.G.M. : Dr. Md. Rezaul Karim A.G.M.: Mihir Lal Roy Technical Director A.F.M. Rafiqul Islam Leather Technologists: Mr. Sirajul IslamCow Wet-blue section: Mr. Shipon Goat Wet-blue section: Mr. Afsar Uddin Sarkar

Mr. Annanto KumarCow Re-tanning section : Mr. Tariqul Islam

Mr. Billal Hossain Mr. Alamgir Hossain

Cow Finishing section : Mr. Moyshan Mohamta Mohesh Md. Jahangir

Chief Mechanical Engineer (U-2): Mr. Makhon LalChief Mechanical Engineer (U-1): Mr. Bimol Babu

Machine Mechanics: 3Supervisor: 4+6=1OAdministrative officer: 10Managerial: 40Production workers: Cow wet-blue section: 350Goat wet-blue section: 200Cow Crust section: 139 (38+101)Cow finished section: 11(2+9)Security Guards: 209. Production Types:All kinds of drum dyed crust & finished leather, Such as:a. Full chrome, semi chrome, chrome free, full vegetable, and chrome free-vegetableFree natural and dried crust leathers.b. Natural and dyed shoe upper leathers.c. Glazed shoe upper leathers.d. Softy shoe upper leathers.e. Lining leathers.f. Pull up, buck and burnished leathers.g. Brush off leathers.h. Plate finished leathersi. Embossed leathers.And also specific leathers on customer’s choice.10. Daily Production Capacity Wet-blue leathers: 60,000 Sq.ft Crust leathers: 50,000 Sq.ft. Finished leathers: 5,000Sq.ft.11. Country of export:Italy, Brazil, Australia, China, France, Germany, Hong-Kong, Holland, India, Mexico, Korea, Japan, Russia, Spain, Singapore, Philippines, Taiwan, U.K., U.S.A.12. Export Quantities: 15, 00000 Sq.ft. per month.13. Production Costs:Wet Wet-blue leathers: 6.0 T.k./ Sq.ft Crust leathers: 10.0 T.k.I Sq.ftFinished leathers: 12 T.k./ Sq.ft 14. Yearly Turnover:USD - 12-13 million. 15. Sister Originations:a. Dhaka Footwear Ltd.b. Dhaka Leather Craft Ltd.c. Dhaka Leather Garments Ltd.d. The Earth International Tannery Ltd.e. Dhaka High Estate Ltd.16. Achievement:Dhaka Hide and Skins received the following National Export Trophy. Year Achievement 92-93-Silver 93-94-Gold 96-97-Bronge 97-98-Bronge 99-2000-Gold 2000-2001-Silver 2002-2003-Gold 2004-2005-GoldThey also achieved the CIP Trophy at 1987-2001 continuously.

National Export trophies Dhaka Food wear achieved the following awards. Year Achievement 1999-00 Silver 2000-2001-Bronge 2003-2004-Bronge2004-2005-Bronge They also achieved the CIP Export award at 1999, 2000, 2001 and 2007. Others Services: a. Telephone b. Internetc. Computerd. Fire Risk: It has enough support against fire.Communication:Tel # 8611263Email # rashidgroup~global.bd.netFax: +880-2-81 11373Web site: www.arashidgroup.com.OBSERVATION OF WET BLUE SECTION Regular Training ActivitiesDay: 01Date: 01/12/08Time: 1l a.m.-l p.m.Observation: (Introduction)Today was the first day of our industrial training. We were five students in a group. Our guide teacher Mohammad Mahtabul Alam went to the tannery with us and introduced us with the senior technologist re-tanning section of Dhaka Hide And Skins Ltd. (DHS)(unit-1), Md. Tariqul Islam. He sent us to the Wet-Blue section (unit-2&3) of Dhaka Hide And Skins Ltd. at 36, kalunagar, Hazaribag, Dhaka-1209.In wet-blue section, we were introduced with Mr. Sirajul Islam, senior technologist of DHS. He told us briefly about the tannery, its rules and regulations and different operations and functions of the tannery. The wet-blue section has two parts, one wet-blue cow section and the other wet-blue goat section. We first started to observe the different operations from cow wet-blue section. Mr. Sirajul Islam helped us to observe the wet-blue section. We saw that the tannery was arranged sequentially.In this section, there are two leather technologists and about 350 workers. It has 53 industrial drums, 20 paddles and 3 fleshing machines. All the drums, paddles and machines are set-up sequentially. We saw large amount of raw hides or skins are processed here everyday. Many people work there and the technologists and supervisors guide them. The working hour of this tannery is 8 a.m.- 5 p.m. All people worked very attentively and carefully. We also observed that a large number of Raw or wet-salted cow hides piles in raw storage and selection section and cow wet-blue piles in wet-blue storage section.We are pleased and enjoyed to observe the leather manufacturing process in large production and acquired vast knowledge and idea and interested to do our training regularly.Day: 02Date: 02/12/08Time: 11 a.m.-p.m.LI: Mr. Sirajul IslamObservation: (Raw cow hides selection)Today we observed the selection of raw and wet salted cow hides. Selector Md. Abdul Motin with 10 workers was engaged for this purpose. He has 15 years experience. He selects the hides with eye observation and experience. He found out different defects from hides and made different lots of different grading. About 100- 150 pieces of cowhides were in a lot. Grain damage, old ages, pin marks, flaying cut, damage by insects & birds, pox, virus, small size, action of hot water, scratch marks etc. were mentionable defects found in raw cow hides. Then we observed different machines.

Day: 03Date: 03/12/08Time: 9 a.m.-11.30 p.m.LT: Mr. Sirajul Islam & Mr. Shipon Observation: (Soaking Operation)Today we observed the soaking operation of cowhides. Soaking is the first tannery operation. During curing, hides and skins lost large amount of its physiological content of water and unless the ‘former regains this water during soaking operation; good quality leather cannot be produced. It is best done in two stages such as pre-soaking and main soaking. Pre-soaking which removes dirt, dung and curing salts from hides and skins. The main soaking rehydrates the hides.Objects of soaking:1. To remove the dirt, blood and dung from the hides and skins.2. To remove the curing salt in case of salted hides and skins.3. To rehydrate the skin proteins4. To open up the contracted fibrous structure of the skins5. To clean off surface filth.6. Softening the hides and skins.In this tannery, soaking is done in industrial drums. Everyday morning, after weighing the raw hides and skins, soaking is done in the following way:Pre-soaking:(All % based on raw/wet-salted weight)300 % water0.4-0.5 % wetting agent (LD-600)0.05 % preservatives (Busan-40L / Proteil-BASF) Run-30’-l hourDrain, Wash: 1-2 hrs, then drain.Main Soaking:200 % water0.5-0.7 % Soda ash (soaking agent)0.5 % wetting agent (LD-600 / NI-extra)0.05 % preservatives (Busan-40L / Aracit-DA) Run-30-lhrThen run the drum 5’per hour and stop up to 12-16 hours.They also used soaking enzyme, sharpening agent and sometimes salts.They used all the chemicals and maintained time very carefully.Check PH: 8-9Day: 04Date: 04/12/08 Time: 7 a.m.-11 a.m.LT: Mr. Sirajul Islam Observation: (Liming Operation)Today we observed the liming operation of cowhides. Liming is done here in drums and in paddles. Liming is a very important operation for leather manufacture. The qualities of the finished leather are largely controlled in liming process. Liming is the operation in which the soaked hides and skins are treated with milk of lime with or without the addition of sharpening agents like suiphides, cyanides, amines, markaptan etc.Objects of Liming:1. To remove the hairs, hooves, nails and other keratinous materials.2. To remove some of the interfibrillary soluble proteins like mucins etc.3. To swell up and to split up the fibers to the desired extent.4. To remove the natural grease and fats.5. To bring the collagen to a proper condition for satisfactory tannage.In this tannery, liming is done in the following way:Liming process: (in drums / paddles) 300 % water0.5 % wetting agent (LD-600, Lisapol)0.7 % Liming auxiliary (Colapel-DL / PA-BASF)5.0 % Sodium suiphide liquor

Run - 1hr.+ 6.0 % Lime liquorRun-1 hr. then stops. After 10 minutes+ 0.5 % wetting agent (LD-600, Lisapol) Run-1 hrThen run the drums / paddIes 5 mm. per hour up to l6-18 hrs for drum liming and 24hrs for paddle liming. Next morning cheek pH: 12.5-13 with pH paper.Then Drain and send for fleshing with fleshing machines.Day: 05Date: 06/12/08Time: 7 a.m.-10 a.m.LT: Mr. Sirajul IslamObservation: (Cheek Liming & Fleshing Operation) Checking Liming:Today we observed the checking of liming operation. Mr. Sirajul Islam (LT) cheeked the liming liquor with pH paper. We also checked the liquor with pH paper. The pH of the liquor was 12.5-13.We cheeked the pH both in drums and paddles. The pelts were swell- up properly, and also so thick, softy, slippery in handle, hair root destroyed satisfactorily.Then the pelts were taken out from the drums and paddles and brought to the fleshing machine for fleshing. We observed the fleshing operation by machine. We also observed some defects in liming pelts. These defects were not so major and they can be removed during next manufacturing operations.Day: 06Date: 07/12/08Time: 7 a.m.-11 a.m.LT: Mr. Sirajul IslamObservation: (Fleshing Operation)Today we observed the fleshing operation of cowhides. To remove fleshes, fats from lime pelts are called fleshing. It is done on the flesh side of the pelts. In this tannery, they used fleshing machines for fleshing and it takes short time and quickly. They have three fleshing machines. In case of large size cow-pelts it is done by hand fleshing knife by men. Fleshing machine operates scientifically. Two operators were engaged for fleshing and about 12-16 workers helped them. On the other hand, we saw four people were engaged for hand fleshing of large cow pelts by knife. They did it so quickly. They have much experience of doing this. We for the first time observed this technique. It gave much experience to us.

Hand fleshing knife Wood frameFig: Hand fleshingDay: 07Date: 08/12/08Time: 8.30 a.m.-10 a.m.LT: Mr. Sirajul IslamObservation: (Weighing Operation)After fleshing the pelts, trimming was done and then took weight and sent for the next operation. We observed the weighing process. We saw 50kgs.weight was on one side of the balance and on the other side the pelts were measured.Day: 08Date: 09/12/08Time: 9 a.m.-1 p.m.LT: Mr. Sirajul Islam Observation: (Deliming Operation)

Today we observed the deliming operation of cowhides. After liming the unhaired & fleshed H/S known as pelt are taken for the next operation called deliming. The alkali present in the pelt is of two types- (a) Free alkali & (b) Combined alkali. The free alkalis can easily be removed by repeated washing with water or by pressing the pelt under the high pressure, but for the removal of combined alkali chemical treatment is always necessary.Objects of Liming:1. To remove most of the lime and alkaline materials from the pelts.2. To reduced the swelling of the pelts.3. Solubilization of Ca-soaps.4. To remove flesh, scud etc.5. To prepare for different tonnage.Deliming process: (in drums)(All % based on pelts weight)150 % water at room temperature.1-3 % Ammonium sulphate0.25- 0.5 % Sodium meta-bi-suiphate0.2 % wetting agent (LD-600, Lisapol) Run-30 mins. -2 hrs.Cheek: Cross-section with phenolphthalein. If colorless, deliming is completed.Then cheeked pH with pH paper.Day: 09Date: 10/12/08 Time: 1. a.m. - 1p.m. LT: Mr. Sirajul IslamObservation: (Bating Operation)Today we observed the Bating operation of cowhides. Limed and partially delimed pelts sometimes require additional treatment known as bating. Bating is done to remove rest lime and selling & plumping.Objects of Bating:1. To make the grain surface of the finished leather clean, smooth and fine.2. To remove some of the non-leather forming proteins materials like albumins, globulins.3. The scud or dirt, short hairs, greases & l~rnc soaps, dark colored pigments and traces of epidermis are all loosened and are easily removable by scudding.4. To allow the splitting up of collagen fibres.5. To make the final leather soft, pliable and stretchy.Bating process: (in drums)0.5-0.8 % Bating agent (EG-98 / PV-KI)0.5% wetting agent (LD-600, Lisapol)Run: 45mins-1 hrs.Day: 10Date: 11/12/08 Time: 10.a.m.-2 p.m.LT: Mr. Sirajul IslamObservation: (Pickling Operation)Today we observed the Pickling operation of cow bides. In leather processing pickling is very important and essential operation prior to mineral tannage. The treatment of delimed or bated pelts with a solution of acid and salts is known as pickling which takes the pelts acidic condition to absorb chrome and being down the pH for chrome fixation. The drum man Amir Hossain & Abul Khaer helped us to obesrved the pickling process.Objects of Pickling:1. To bring the delimed or bated pelts to a required degree of acidity before chrome tannage, even vegetable tannage.2. To reduce the pH3. To modify the fibre structure.4. To reduce the astringency of chrome tanning agents.5. To preserve the leathers and to achieve the special effect.

Pickling process:(in drums)80 % Water8% Salt0.5 % Sodium formate0.25 % Impropal Co0.25 % Preservatives (Busan - 40L)Run-15 minutesCheek: Be°7-7.5+ 0.25 % Formic acid (1:10 dilution) Run- 15 minutes+ 1.2 % Sulphuric acid (H2S04) (dilute with 60 % water)Add ‘/2 of the liquor and run-15 minutes.Then add the rest Y2 of the liquor and run-15 minutes.Then run the drum about 3 hours and stop running. Leave overnight.Next morning,+ 0.25 %HypoRun-30 minutes Cheek pH: and cross-section with Bromocresol green.Day: 11Date: 13/12/08 Time: 9.00 a.m.-l p.m.LT: Mr. Sirajul IslamObservation: (Chrome, Tanning Operation)Today we observed the chrome tanning operation of cowhides. In leather manufacture the most outstanding process is Tanning. The process of converting the putrescible hides and skins into non-putrescible leather is called Tanning. The materials, which are used for tanning, are called Tannins. There are various process of tanning such as- Chrome tanning, Semi-chrome tanning, Vegetable tanning, Aldehyde tanning, oil tanning, Zr tanning, Alum tanning, White tanning etc.Objects of Tanning:1. To convert the putrescible hides and skins into non-putrescible leather2. To raise the shrinkage temperature & to increase the resistance to hot water of the leather.3. To reduce the ability to swell when wet back.4. To increase the strength properties of leather.5. To stabilize the leather against enzymatic degrading.Tanning process:In this tannery, Full chrome, semi-chrome, vegetable, white tanning are mostly done. We first observed the Chrome tanning process. It is done here in the following way:Drain 1/2 of the pickle bath4.0 % Basic chrome powder (Chromosol B-Bayer,Sulcbrome- Stopani, Chromitan(B-BASF)Run- 60 minutes.+ 1.0 % Implenal DC+ 0.1 % Preservatives (Busan-40L)Run-30 minutes+ 4.0 % Basic chrome powder+ 1.0 % Sodium formateRun- 2hrs.Add + 50 % water0.4 % Tan base(Neosyn MgO)Run- 7 hrs.Cheek pH: pH=3.7-3.8Cheek cross-section: Bluish-green color appeared through the whole leather.Then Drain and Piles the Wet-Blue leather for ageing.

PH: 8.0-8.5

Day: 12Date: 14/12/08Time: 10 a.m.-1 p.m.LT: Mr. Sirajul Islam Observation: (Wet-Blue Leathers selection)Today we observed the wet blue leathers. After pre-tanning with Basic chrome powder, the hides and skins are called wet-blue leathers, as the color of the leathers is Bluish-green. We saw many piles of wet-blue leathers in the tannery. It is necessary to age the wet-blue leathers for few days for better chrome fixation.Then we observed the selection of wet-blue leathers. Selector Shahjahan told us about selection. He selected the leathers in accordance with grading. The leathers of Grading 1, 2, 3 are kept in one lot, Grading 4, 5, 6, 7, 8 are kept in another lot, and the much defected leathers are included in grading 9& 10. The crust and finished leathers are manufactured from these wet blue leathers according to customer’s demand.Day: 13Date: 15/12/08 Time: 10 a.m.-1 p.m. LT: Mr. Sirajul IslamObservation: (Samming to shaving)Today we observed the samming, Splitting and shaving Machines and their functions. In this section there are 2-samming m/c, 2-Splitting m/c and 4-shaving machines.Samming by machineTo reduce water from the wet-blue leather by a roller-squeezing machine called samming machine.Object:1. To reduce water from the leather2. To add the chemicals for next operationObservation: less thicker leathers were found.Splitting by machineThe band knife splitting machine split the leather into two or more pieces if the leather is too thick. The object is to get the required thickness. Example: for shoe upper leather-thickness, 3-1.4 mm.Shaving by machineThe wet-blue leathers are shaved to get required thickness. After shaving wet-blue leathers are sent to Unit-I of Dhaka Hide and Skins Ltd. for the manufacture of crust and finished leathers.Day: 14Date: 16/12/08 Time: 10 a.m.-1 p.m.Today we drew the plan layout of cow wet blue section of Dhaka Hide and Skins Ltd.Observation of Goat Wet-Blue Section(Unit-3)Day: 01Date: 17/12/08 Time: 9 a.m.-1 p.m.LT: Mr. Afsar Uddin Sarker Mr. Annonto Kumar Observation: (Raw selection & soaking)Today we observed the manufacture of goat wet blue leather. Leather technologist Mr. Afsar Uddin Sarker helped us to observed the different operations of leather processing in this section. We first observed the selection of raw goat skins. Then we observed the manufacturing process of goat wet-blue leathers. It is done here in the following way:Pre-soaking:500 % Water0.05% Preservatives (Busan 40L)0.25 % Wetting agent(LD- 600)Run- 30 mm.Wash in running water until the leather becomes clean.Main-Soaking:

500 % Water0.1% Preservatives0.5 % wetting agent1.0 % soda ash Run-60 mm.Leave for over night and run the drum 5 mm. per hour up to 18 hours.Day: 02Date: 18/12/08 Time: 10a.m.-1 p.m.Observation: (Liming)300 % Water1.0 % Liming Auxiliary0.5 % Wetting agentRun- 15 mm.+ 2% Lime 3 % Sodium suiphide Run- 60 mm. Then rest 60 mm.+ 2% Lime+ 3 % Sodium sulphide Run- 60 mm. Then rest 60 mm.Leave over night, run 10 mm. per hour up to 24 hours.DrainFleshing by fleshing machine. Then weight the pelts.Day: 03Date: 20/12/08Time: 10 a.m.-l p.m.Observation: (De-Liming)Single Dc-liming:200 % Water0.5 % Ammonium Sulphate Run-25 mm.Double Dc-liming:100 % Water1.5 % Ammonium Sulphate0.5 % Sodium-bi-suiphate Run- 45 mm.Observation: (Bating)+ 1.0 % Bate powder Run- 60 mm.+ 0.3 % Formic acid Run-10 min.heek pH: 6.5-7.0+ 0.5% Acid bate+ 0.5 % Wetting agent (LD-600) Run-60 mm.Then Scudding by scudding knife.Observation: (Pickling)+ 80% Water+ 10 % SaltRun- 15 min.+ 0.5 % Formic acid Run-30 min.+ 1.0 % Sulphuric acid (dilute) Run- 60 min (30’+30’)+ 0.3 % Impropal CO Run- 60 min.Cheek salt concentration: 6-7 °BeLeave over night.Next day, + 0.5 % Hypo Run-30 mm. Cheek pH: 2.7-3.0

Day: 04Date: 21/12/08 Time: 12p.m.-3p.m.Observation: (Chrome Tanning)+ 4.0 % Chrome powder Run-60 mm.+ 1 .0% Implenal DC+ 0.1 % Preservatives Run- 30 mm.+ 4.0 % Chrome powder+ 1.0 % Sodium formate Run-2 hours.+ 50% Water+ 0.4 % Neosyn MgO Run-7 hours.Check pH: 3.7-3.8Day: 05Date: 22/12/08 Time: 11a.m.-lp.m.Observation: (Wet Blue Grading)Selector Shahjahan told us about selection. He selected the leathers in accordance with grading. The leathers of Grading 1, 2, 3 are kept in one lot, Grading 4, 5, 6, 7, 8 are kept in another lot, and the much defected leathers are included in grading 9& 10. The crust and finished leathers are manufactured from these wet blue leathers according to customer’s demand.Samming by machineTo reduce water from the wet-blue leather by a roller-squeezing machine called samming machine.Object:3. To reduce water from the leather4. To add the chemicals for next operationObservation: less thick leathers were found.Shaving by machineThe wet-blue leathers are shaved to get required thickness. After shaving wet-blue leathers are sent to Unit-i of Dhaka Hide and Skins Ltd. for the manufacture of crust and finished leathers.Day: 06Date: 23/12/08 Time: 10a.m.-lp.m.Observation: (Manufacture of full chrome natural leathers of goat skins)The process is given below:Wet-back:200 % water0.5 % wetting agent (LD-600, Lisapol)0.25 % Acid (Oxalic / Formic /Acetic) Run-60 mm.Cheek pH: 3.2-3.3Drain, Rinse-l0minutes.Re-chroming:+ 100% Water+ 0.2 % Formic acid Run- 15 mm.+ 4.0 % Chrome powder+ 2.0 % Chrome Syntan+ 0.5 % Sodium formate+ 0.1 % Cationic fat Run- 60 mm. + 2.0 % Acrylic resin syntan (Relugan-RF (BASF), 2004-I CAP)Run- 30 mm. + 2.0 % Sodium formate +1.0 % Neutralizing syntanRun- 90- 120 mm.Cheek pH: 3.7- 3.8Leave over night, then drain, wash well.

Day: 07Date: 24/12/08 Time: 11a.m.-lp.m.Observation: (Neutralization operation)50% water at 45°c2.5 % Neutralizing syntan (Neosyn-BS3 / Tymol-NA / Neutrigan (PAKS)2.0 % sodium formate Run-60 mm.Cheek pH: 4.4- 4.5Drain, washObservation: Re-tanning operation)+ 100% Water at 45°c+ 3.0 % Acrylic resin syntan (Relugan RS3 Run- 20 mm.+ 4.0 % Basytan DLE (BASF)+ 3.0% Taniganos+ 2.0 % Butan 7816 (Buckman) Run- 30 mm+ 4.0 % Basytan DLE (BASF) (Bleaching syntan)+ 3.0% Tanigan OS (Replacement syntan)+ 3.0 % Relugan D ( Melamine based syntan)Run- 60 mm.Drain, Rinse.Day: 08Date: 25/12/08 Time: l1a.m.-lp.m.Observation: (Fat liquoring operation)150 % water at 60°c2.0% Lipoderm liquor SC1.5% SyntholFL-3271.0 % Sandolux WWL0.5 % Synthol ICA0.1% Preservatives (Busan 40L) Run- 45 mm.Fixing:+ 1.0 % Formic acid Run-30 mm.Cheek pH: 3.7-3.8Leave over nightDay: 09Date: 27/12/08 Time: 10a.m.-lp.m.Observation:Setting, Vacuum drying, Tunnel drying, Staking, Toggling, Trimming, Ironing, Selection grading (1 to 10) and Measuring the crust leather.Day: 10Date: 28/12/08 Time: 1la.m-lp.m.Observation: (Full Vegetable pre-tanning)After pickling,Add, 1% Alum (Fitkiri) Run- 60 mm.+ 2 % Chrome powder Run-60 mm.+ 2.5 % Pre tanning materials (Neosyn RW) Run- 60 mm.+ 0.4 % Neosyn MgO (Tanbase)Run- 5-6 hoursCheek pH: 3.7-3.8Horse up, piles.

OBSERVATION OF CRUST SECTIONObservation of the Re-tanning and crust section(Unit-1)Day: 01Date: 30/12/08Time: 11 a.m.-1 p.m.LT: Md. Billal HossainObservation: (Re-Tanning section)Today was the first day of observing the re tanning section of Dhaka Hide And Skins Ltd. (Unit-I). We met with Mr. Tariqul Islam & Mr.Billal Hossain, Technologist, re tanning section. Then he guided us to observe the different operations of the re-tanning section. Re-tanning is done in drums. There are three mega re tanning drum and thirteen industrial drums in this tannery. The drum men were busy to maintain the drum and adding different chemicals. We saw different types and color of leathers was manufactured. Semi-chrome natural, shoe lining, shoe upper, white leather, Chrome free-vegetable free leathers etc. The r.pm. of retanning drum was 12-13. Then we observed the setting operation. There are six setting machines here. After finishing the re tanning operation water and unbound chemicals are removed and to remove the wrinkle and crease setting is done. Then we observed the drying operation in tunnel dryer and vacuum dryers. We also observed different chemicals and fats used here. A lot of leathers were hanging for drying. We also observed different machines used here.Day: 02Date: 31/12/08Time: 11 a.m.-3 p.m.Observation: (Wet back and Re-chroming operation)Before retanning it is necessary to wet back the shaved wet blue! wet white leathers. It is done with acid, wetting agent and water. Acid is used to bring the leather of optimum pH for re-chroming. Re-chroming is done to increase the strength of leather, to fix more chrome into the leather, to increase the hydrothermal stability and shrinkage temperature, to improve the softness, fineness of the grain etc.Wet- back: (All % based on shaved weight)+ 200 % water+ 0.2 % wetting agent (LD-600, Lisapol)+ 0.25 %Acid(Oxalic / Formic Acetic) Run-30 mm.Cheek pH: 3.2-3.3Drain, Rinse-10 minutes.Re-chroming:+ 100% water at N.T.+ 4-6 % chrome powder (Chromosol B-Bayer,Sulchrome- Stopani, Chromitan B-BASF)+ 0.5-1.0 % Formate/ Neosyn N Run-45- 60 mm.+ 1-2 % Acrylic resin syntan (Relugan-RF (BASF), 2004-I CAP) Run-30min.+ 2.0% Aldehyde Run-30min+ 0.5% Sodium formate. Run- 30min.+ 1.0% sodium- bi- carbonate (dilute)Run-90 mm. (30’ + 30’ ±30’)Cheek pH: 3.6-3.8Leave over night, then drain, wash well.Day: 03 Date: 01/01/09Time: 7 a.m.-10 a.m.Observation: (Neutralization operation)The process of deacidification or the excess of free or easily liberated strong acid in leather, prior to, retanning, dyeing and fat liquoring, is popularly called neutralization.Objects of neutralization:1. To remove the neutral salts and uncombined chromium salts from the leather.

2. Neutralization of free acid in the leather formed by the hydrolysis of the chrome complex.3. To control the affinity of the leather for anionic materials, particularly dyestuff and anionic oil emulsions by regulating its electrostatic charge.Process and chemical used:+ 150% water at 45°c+ 2.0% Neutralizing syntan (Neosyn-ES3 / Tymol-NA / Neutrigan PAKS)+ 1.0 % sodium formate Run-45 mm.+ 0.5% sodium- bi-carbonate (dilute)+ 0.5% synthetic fat liquor(Synthol SL-335 / Synthol FL-327/ Remsol C2) Run-30 mm.Cheek pH: 4.5-4.8 with bromocresol green solution, Bluish-green Drain, Wash well.Day: 04Date: 03 /01/09Time: 10 a.m.-1 p.mObservation: (Re-tanning operation)Today ewe observed the retanning of cow semi-chrome natural leather. Mineral tanned leathers-particularly the chrome or aluminum tanned leathers-are nearly always retanned with a view to modifying the properties of the finished leather to suit modem demand.Objects of re-tanning:1. To fill the loose and softer parts of the leathers to produce leathers of more uniform physical properties.2. To allow for the production of unlined footwear.3. The retannage may improve the chemical stability of the leather, particularly its resistance of alkalis and perspiration.Process and chemical used:Water at 45°cButan-7810LT (Buckman) Run-50 min.+ TSF (pies-cuadrados) (fats) Run-15 min.+ EM Run-45 min.+ Pie-tan A-40 Run-45 mm.+ WaterPie-tan PCMimosa (SETASUN-Brazil)Sodium-meta-bio-sulphateTanigan OS Two times (30’+ 70’)Cheek penetration+ Formic acid Run-30 mm.Day: 05Date: 04/01/09Time: 10 a.m.-l pmObservation: (Dyeing operation)In this tannery, different dyes of different colors are used in leather processing. Some dyes and their company name is given below:Name of dyes CompanyORANGE ERN COLORANTES INDUSTRIES (Spain)ORANGE ZGN ,,BLACK 3Th ,,BROWN CUERO ,,Derma Brown D2RP ClarientLanuilux Brown BGP ,,CBS BROWN ADP Country of origin-ItalyCBS BLACK TOP ,,

Day: 06 Date: 06/01/09Time: 11 a.m.-1 p.m.LT: Md. Tariqul IslamObservation: (Fat-Liquoring)Today we observed the Cat liquoring operation of cow leathers. It is very important operation for leather manufacturing and it depends on type of leather to be manufactured. The process of fat liquoring entails the treatment of leather with a warm dilute emulsion of oil in water. The function of fat liquoring are; Lubrication, adjust of physical properties.Objects of Fat-liquoring:1. To improve the softness of the leather.2. To improve the sliding properties of the leather.3. To improve the toughness, water-repellent properties of the leather.Chemicals Used in Fat-liquoring: Hot water+ Trilon B Run-5 minutes+ Fats+ Preservatives (Busan 40L)Run-50 minutes + Paramel PA Run-30 minutes+ Formic acid (dilute) Run-40 (10+30) minutesDrain, Rinse.Some fats used in this tannery:Chemicals Name CompanyTSF Pies-CaudradosCSSSNEUREKA-FG Atlas-USAEUREKA-400R Atlas-USAEUREKA-400FL Atlas-USASynthol-AK Smith & ZoonSynthol FL-327 Smith & ZoonSynthol SL-335 Smith & ZoonPolyfol-SSF ABHI (Abhilash Chemicals Pvt. Ltd.)Polyfol-HLN ABHIPolyfol-LN ABHILipoderm Licker-SP BASFLipoderm Licker-SC BASFDensotan-A BASFDay: 07Date: 07/01/09 Time: 3 p.m.-5 pm.Observation: (Dyeing and Top Fat liquoring)Water at 45ccDye Run -20 mm.+ Formic acid (dilute)Run -30 mm.+ Cationic fat (Permol NC/ Catalic-G! LLSO)Raw oil (Synthol-O / Oil-SK)Run - 30 mm.Cheek penetratio.Drain, Horse-up overnight.

Day: 08Date: 08 /01/09 Time: 10 a.m.-12 pm.Observation: (Setting)Today we observed the setting operation. It is done to reduce water and crease from the leather. There are six setting machine here. We saw that the operators and workers were busy for setting the Ecological tanned leathers, Black lining leathers, yellow lining leathers, black upper leathers in setting machine. Two rollers in setting machine pressed the leather. The objects of setting are:1. To reduce water from the leather.2. To increase the area of the leather.3. To remove the crease.4. To increase the compactness of the leatherDay: 09Date: 10/01/09 Time: 10 a.m.-12 pmObservation: (Vacuum Dryer)In order to dry the leather, vacuum dryer is used where leather is dried under certain temperature and pressure. There are two vacuums dryer in this section. Four operators are engaged in this purposes and the workers helped them. They worked very rapidly. After every 30 seconds the platform of vacuum dryer pressed the leather and thus dried it. The pressure was .5 bar and temperature 60°c. After vacuum, the leather was partially dried and produced smooth grain.Day: 10Date: 11/01/09 Time: 10 a.m.-1 pmObservation: (Tunnel Dryer)Tunnel is like a long closed room where the leathers are hanging turn by turn in the pipe, which rotates by gear. As a result the leather circulates from one end to another in tunnel. Hot air by exhaust fan passed through the tunnels and thus the leather dries up. It takes 45 minutes to complete one turn and then every 37 seconds later leather are removed from the tunnel. Two men were engaged for the purpose.Day: 11Date: 12/01/09Time: 11 a.m.-1 pm Observation: (Staking)Today we observed the staking operation. Staking is done to make the leather soft and smooth. There are two vibration staking machine in this tannery. Four operators were engaged for this purpose and four workers helped them.Day: 12Date: 13 /01/09 Time: 11 a.m.-1 pmObservation: (Toggle Drying)After staking, the leathers were sent to toggle dryer for drying. There was a continuous toggle dryer here. The object of toggling is to dry the leather by passing hot air into the toggle dryer and to stretch the leather i.e. to increase the area of the leather. Eight people were engaged for this purpose and six people helped them. They worked so fast with experience.Observation: (Trimming)It was done to give the leather a suitable shape and to cut out the defected area of the leather.Day: 13Date: 14 /01/09Time: 11 a.m.-1 pmObservation: (Kiss-plate)This machine has another name hydraulic press machine. This machine applies heavy weight with plane plate on the leather. As a result, Smooth and glossy grain surface is appeared on the leather. There were three kiss-plates in this tannery. By changing the plate of different design, the appearance of that plate produced on the leather.

Day: 14Date: 15 /01/09Time: 11 a.m.-1 pmObservation: (Leather machines)Today chief mechanical engineer Mr. Makhon Lal helped us to observed different machines present in this tannery and shortly described their functions.Day: 15Date: 17/01/09Time: 11 a.m.-1 pmObservation: (Plan layout)Today we drew the plan layout of Retanning and crust section of this tannery.OBSERVATION OFFINISHING SECTIONObservation of the finishing section: Day: 01Date: 19/01/09 Time: 11 a.m.-1 p.m.LT: Md. Zahangir AlamToday we observed the finishing section of Dhaka Hide and Skins Ltd. (unit-1) (First floor). In this section, we observed the following things:Number of Technologists : 02 LT: Md. Zahangir Alam, Tariqul Islam Number of Operators : 02 (Salim, Delower)Number of Workers : 09Number of Auto Spray m/c : 04 (3-From Carlessi Italy, 1 fromCompuspray 2001 India)Number of Roto Press m/c : 01 (Torino-Italy)Number of Ironing/Embossing/ Hydraulic press m/c : 03Number of Measuring m/c : 02Definition of finishing:The last and most important operation in a tannery today is finishing where the leather surface is coated with nice looking, colored or colorless, flexible, stretchy, durable film of some film forming materials. Finishes on leather also serve as a protective coating.Purpose of finishing:1. Levelness of color on the leather.2. Uniformity of shape from leather to leather.3. Changing the color to that which is required.4. Giving a surface to the leather varying from matt to gloss.5. Adding a transparent film through which the natural appearance of the leather may be viewed.6. Render the leather fast to acids, alkalis & perspiration.7. Render the leather resistant to repeated flexing.Day: 02Date: 21/01/09 Time: 11 a.m.-1 p.m.LT: Md. Zahangir AlamObservation of Auto spray Machine:To we observed the auto spray machine and its functions. There are four auto spray machines in this tannery.3-from Carlessi Italy, 1 from Compuspray 2001 India. These machines are used in leather finishing. In finishing this tannery specialize in natural looking aniline & semi-aniline finishes with good look & touch, following the latest market trends. The ranges of their finish products are:Aniline, semi-aniline, Glazed, Embossed, Plate, milled, Burnish, Polished leathers etc.To we observed the semi-aniline finish of cow leathers by auto spray machines. This machine has microprocessor unit, which maintain the whole process and also has some spray gun that move roundly and spray on the leather. The leather is moving over the belt, the sensor measure the leather

area and give input to the microprocessor. Then it gives instruction to the spray guns. When the leather passes through the spray gun chamber they continuously spray on the leather. Then it passes through four dry chambers for drying. All the operation is done automatically. The process in done in the following way:Semi-aniline Finish(1). Staining Coat:Chemicals Amounts (in grams)Supemil HK Black (Clarient) 50grmWater 900grmIso Propayl alcohol (IPA) 50 grm

Total= 1000 grm IX Spray, Then dry. (2). Season Coat:Chemicals Amounts (in grams)Melio Resin 777A 60Melio Resin 93 1A 50Melio Resin 943A 50LUSTRARLUT 70MELIO TOP 288 40 SFT F 6004 50 MELIO WAX 180 40WATER 450MELIO PROMUL 70 60Pigment, Black PA 100Dye, SHK. Black 30

Total= 1000 grams 2X Spray, Then dry.Sand blast 70°c, 150 pressuresAgain same solution 4-5 X Spray, Then dry.(3). Top Coat:Chemicals Amounts (in grams)MELIO WF 348 50Water 1000

Total= 1050 grams2X Spray, Then dry.Check: 100% fastness.Final Product Sample Day: 03Date: 22/01/09Time: 3 p.m.-4.30 p.m.StakingThere are two staking machine here. Staking is done here by plain plate in staking machine at 70°c temperature and 30-bar pressure. Then staking by staking machine to make the leather soft and smooth.Day: 04Date: 24/01/09Time: 3 p.m.-4.00 p.m.Roto-press machineToday we observed the roto-press machine. One machine from torino-Italy is in this tannery. It is used to give glazy appearance on the leather. We observed the roto pressing on cow shoe upper leathers. It is done at 110°c temperature and 40-bar pressure.

Day: 05Date: 25/01/09 Time: 3 p.m.-4.30 p.m.SelectionToday we observed the selection of finished and crust leathers. The selector selected the leather according to grading. Good quality leathers were kept in grading 1, 2 & 3. Less defected leathers in grading 4-6, then grading 7, 8, 9, 10, or rejected according to the type of leathers.Day: 06Date: 26/01/09Time: 3 p.m.-4.30 p.m.MeasuringToday we observed the measuring of finished and crust leathers. There are two measuring here. The machine measures the whole area of the leathers in square-feet. It can measure quickly and accurately. Then the value of the leather is calculated. The rate is calculated in US $ 1.8 per square feet leathers.PackagingFinally the leather is packed for export according to buyers order.Day: 07Date: 27/01/09Draw Plan layoutToday we drew the plan layout of re-tanning, crust and finishing section of Dhaka Hide And Skins Ltd.Day: 08Collect InformationDate: 28/01/09Today we collected different information about management system, stuff, the products manufactured in this tannery, their daily production, number of technologists, technicians, operators, workers, the machines available here and many other unknown information from Mr. Tariqul Islam (LT, re tanning section), Mr. Zahangir Alam (Finishing Section) and others.Day: 09Final observation Date: 29/01/09Today we finally observed the whole tannery, different operations that running then, different machines and collect information. As the last day was Friday, so today was the last day of our industrial training.Working PlanOur industrial training duration was for two months. So we have finished our observation in the tannery by the following schedule:

1. Introducing 1 day2. Industry observation 2 days3. Raw selection 2 days4. Observation of cow wet-blue 12 days5. Observation of goat wet-blue 8 days6. Observation of grading 2 days7. Observation of cow crust section 15 days8. Observation of cow finishing section 09 days

Total 51 days

Flow Chart of Leather ManufacturingRaw selectionShortingTrimmingWeighing (raw weight)Pre-soakingSoakingUnhairing (if necessary)LimingFleshingWeighing (felt weight)De-limingBatingScudding (if necessary)PicklingDe-pickling (if necessary)De-greasing (if necessary)Pre-TanningBasificationWet-Blue LeatherPillingAgeingWet-Blue selection & gradingSammingSplitting (91necessary)ShavingWeighing (shaved weight) Wet- backRe-ChromingNeutralizationRe-tanning & Dyeing Fat-liquoringFixing/ Top fatHorse upSetting by rn/cVacuum, by rn/cHang to dryStakingTogglingTrimmingHydraulic press / kiss-plateCrust LeatherAuto sprayingStatingRoto pressFinished leatherSelectionMeasurementPackagingExport

Leather machines and Equipments used in this tannery:Cow wet-blue section:Name of machines NumbersIndustrial drum 53

Paddles 20Fleshing rn/c 3Hand fleshing knife 10Samming rn/c 2Splitting rn/c 2Shaving rn/c 4Goat wet-blue section:Industrial drum 16Mega-retanning drum 2Paddles 12Fleshing m/c 4Samming m/c 1Shaving m/c 2Dyeing drum 2Setting m/c 4Vacuum Dryer 1Tunnel Dryer 1Continuous Toggle Dryer 1Hydraulic Press m/c 1Measuring m/c 3Cow re-tanning & Crust section:Industrial drum 13Mega-retanning drum 3Small testing drum 2Dye mixture 1Setting machine6Vacuum Dryer 2Auto Tunnel Dryer 1Continuous Toggle Dryer 2Vibration Staking machine 2Jaw Staking machine IBuffing machine 1Cow Finishing section:Hydraulic press / Kiss-plate m/c 3Auto Spray machine 4Roto-press machine IPolishing machine 1Glass Glazing machine 8Milling Drum 3Measuring machine 2Inter-Intra Discussion:We have observed in the industry that what we have learned are not same but similar. Example: a) We have learned that if we want to produce garment L/R, shoe upper L/R, lining L/R thus we have to control raw materials from wet blue section and maintain Industrial process.But in the Tannery they do not do this. They follow a same process in wet blue section for garments L/R, lining L/R, and shoe uper L/R. b) In practice we measured the water accurately but in industry it is not look very necessary. They used water on basis of their experience. Situation of the company position comparing with local and International arena: By the close observation I can say that it is a large-scale leather industry in our country and abroad. Although it is not the number one leather industry in Bangladesh but in future it can up grade its position by changing some of its systems. I hope it will be a well known name in leather sector. All ready the industry has expand it, as Karim footwear, Karim leather products, Kamtex limited, which are its sister organization.

Tannery Problem:Since Tannery is a large production area, so it is natural to have some problems of Some problems that we noticed in the tannery are followings:1. The Environment of the tannery is not suitable for health.2. The tannery has no water treatment plant.3. Most of the section is witty and dirty.4. There is no proper drainage system.5. The number of technologists is very few.6. There is no suitable room for leather technologists.7. The lack of skilled and experienced workers.8. There is no facility for the recreation of the workers.9. The salary of the workers is less.10. The tannery has not enough facility to clean up the waste/dust of it.11. Most of the machines are manual, not computerized.12. They don’t follow the standard method of processing.13. There is not enough facility for material handling.14. There is not proper air circulation system in the tannery.15. They have not enough facility for research.Beside these, there are a lot of internal problems of the tannery, which is unknown to us.Solution:To overcome these problems, the management and all stages of people should be conscious.1. They should build up a water treatment plant. It is not a highly expensive project.2. They should try to keep the tannery clean and make the environment suitable for health.3. The govt. should invest enough loans for the tannery.4. They should buy modern computerized machines for the processing.5. They should try to reduce the manufacturing cost of the leather.6. They should have a research laboratory, in which they can try to upgrade the technology for L/R production.7. They should maintain a standard plant layout so that they can reduce the production time and cost.8. They should maintain a recreation room for the workers.Conclusion:Leather industry in a Bangladesh is a highly potential sector. Bangladesh has a large pooi of cheap labour force and adequate supply of raw materials in this leather sector. Further hide and skin of Bangladesh have good demand in international market, because of their fine fiber structure and grain. But it could not prosper mush because of proper planning, well skilled manpower and executive skilled leather technologists.It is true that executive skill is, to a large extant a God given attribute and is a matter of sixth sense, an intuitive factory that defies explanation a hunch which always tells the right thing to do at the right time. But at the same time one can improve hi quality and skill through repeated practice careful observation and penetrative thinking.When theoretical knowledge and practical works runs together then the technologies begin to grow upwards. So, to be a well skilled executive leather technologist, industrial observation is one of the crying needs. And our country Bangladesh badly needed some executive skilled leather technologist for upgrading the leather sector.