Dyestuffs Reporter: Challenges of Dyestuff Industry

Excerpt: India is leader in production and export of reactive dyes whereas China with disperse dyes, azo dyes and dyes intermediates

Sauradip Chemical Industries Pvt Ltd Visiting Fellowship Lecture by Dr.Nilesh Mistry

DR.NILESH MISTRY, Chief Technology Officer, Lonsen Kiri Chemical Industries Ltd (Indo-Chinese Joint Venture formed on 19th July 2009), Vadodara with installed capacity of 4000 tons per annum (15% of Indian installed capacity - 56% of reactive, 18% disperse, 15% acid and 7% azo dyes) presented a maiden lecture on Challenges of Dyestuff Industry – A sincere effort towards accepting challenges on 15th April 2019 at K.Venkataraman Auditorium at ICT. Sauradip Chemical Industries Private Limited under with endowment for Dyestuffs and Textiles Processing Technology hosted the lecture. Prof G.S.Shankarling, Head, Department of Dyestuff Technology welcomed the attendees.

Dr.Kishore Shah, Distinguished Alumnus of ICT and Chairman of Sauradip Industries, acknowledged his training at the institute which earned him dividends and the spirit of writing books. In return, he donated to his Alma Mater of the upgradation at Polymer & Surface Engineering Department besides the current lecture series to enhance industry academia interaction. Mr.Rajiv Shah, Managing Director spoke on customised performance of chemicals with core values of care, trust and creativity and showcased video on power of discipline. Mr.Jaideep Shah, Executive Director also spoke on customer service citing an instance of credibility that played significant role for business growth and attitude to give back to customer and employer.

Introducing Dr.Mistry, Padmashri Prof G.D.Yadav, Vice Chancellor said he obtained PhD in Dyestuffs and Intermediates from Gujarat Technological University and had a stint of 27 years in industry. Dr.Mistry gave lucid insights in 12 areas on challenges to dyestuff industry and Lonsen Kiri for overcoming the same in a competitive world and innovation leadership followed by showcasing aerial view of the factory plant and equipment and operations.

Pharma vs. dyes industry: Pharma requires products with 99.5% purity (GC, HPLC, Mass, IR) as they are intended for human consumption. Dye industry does not require pure products as such, and shade matching is done by mixing with brighter shade e.g. Standard Red dye with bluer tone. Multifibre (nylon shade) testing of dyes (Reactive Black WNN) with different tones and desired matching with use of impurities (7-13%) assessed by HPLC.

Dyes and Intermediates industry: China is the largest manufacturer followed by India (share of 16% world production). India is leader in production and export of reactive dyes whereas China with disperse dyes, azo dyes and dyes intermediates. Vinylsulphone and H-Acid are key raw materials. Besides export and import, India's production capacity of Vinylsulphone and H-Acid are less than demand. Volatility in the price of VS is in the range of 250 enhanced to 415. H-Acid production cost is 400 which shot up to 1300 owing to closure of Chinese companies and increased demand.

European, Japanese and Indian dyes industry – Methodology: Reactive Black 5. Testing in-process whereas Japanese do not follow in-process testing since use of right quality raw materials and quantity according to standard parameters to get the desired product without variation. Chemicals have specific physical and chemical properties. This cannot be followed in India since raw materials are purchased from various sources with different quality, solid contents, insoluble and the batches should conform to same quality.

Achieve best results and grow with the industry: Best chemistry principles for best output. For optimisation of reaction, stoichiometric calculation (molar ratio of chemicals) may be followed to avoid undesirable by-products apart from any required by-products. Allow maximum possible concentration (30-35%) e.g. with 10-15% solid contents, same batch can be produced but output is less resulting in less competitiveness. Therefore, effective utilisation of available reactors, equipment capacity, occupancy of equipment and time set are important.

Lansen-Kiri follows improvement in different areas: Coal consumption (1.87 kg per plant per 1 kg product in 2013 reduced to 0.75 kg in 2019). Further, 1.1 kg reduced to 0.7 kg using good coal quality with calorific value besides particle size for effective utilisation. Next step is water conservation for effective utilisation by planning pattern e.g. red dye production without change of products to preclude washing in plant. This has resulted in reduction of water consumption from 17 Kl per I ton to 9 KL in 5 years making it competitive against other manufacturers. Solid waste reduction – powder on spray drying may release dust particles into atmosphere. Hence, modification and investment in spray dryer, solid content of liquid is reduced, solid waste from 3% to 1% resulting in saving of Rs.5 crores per annum.

Usage of solid waste: Various steps in intermediates synthesis generate acidic effluent, which is neutralised with alkali to sodium sulphate followed by filtration. Recovered salt has been consumed, 4 tons for 36 tons; 8 tons for 51 tons Black mix dyes, thereby saving in cost of disposal besides waste and purchase.

Liquid waste: RO Membrane process generates permeate containing 2-3% dye (molecular weight of 800-900) which was recovered and concentrated to 15-30% for use in mix dye (Black mix contains yellow, orange). Environmental protection: Though, they have permission to discharge around 200 KL treated water to effluent channel, self-imposed Zero Liquid Discharge since last 4 years. Effluent is collected into ETP, segregated, treated in multi-effect evaporator and distilled off to 70% of distilled water having 25% COD, TDS for reuse in production. 30% concentrate is spray dried in-house or at external agency before disposal to landfilling site.

Occupational Health and Safety: Of employees by regular audits. Safety and Fire-fighting are equally important for prevention of accidents. Regular training of fire-fighting besides lectures are conducted to this effect.

Water conservation: Videos were shown on rain water harvesting (by gutters) for collection of water in pond during monsoon and environment protection. This is pure water which they reuse in processing. They celebrate Environment Day and Tree Plantation Day.

Storage area: To achieve the highest production, storage of raw materials segregated categorywise (acidic or alkaline) and finished goods productwise are necessary. For commitment to customers in the next 3 months, yearly production planning, storage capacity and money for strategic purchase are important. Raw materials are purchased in advance. Finished material packed directly from spray drying units into pallets (500 tons) for despatch. Besides storage and raw materials, good work place is a must without obstacles and colour contamination.

Awards and Excellence: From Gujarat Chief Minister in 2015-2018 and Quality award. GPCB quotes their company to others to maintain environment and cleaner chemistry. Proposing Vote of Thanks, Prof R.V.Adivarekar, Department of Fibres and Textile Processing Technology offered special thanks to Dr.Mistry, Prof Yadav and Dr.Kishore Shah. Mr.V.D.Patil (President Indian Specialty Chemical Manufacturers' Association) hosted high tea. The lecture ended with answers to questions and National Anthem.

Author Details

K.S. Murthy

Pidilite Industries Ltd.