Vijayeswari Textiles in India protects the environment with a treatment plant for wastewater at its textile finishing plant that gives no discharges whatsoever. The use of bio-scouring helps reduce the level of effluents, making water treatment easier.
Vijayeswari Textiles in Coimbatore is one of Indias few textile mills to have zero discharges of effluents. Other companies send their wastewater to a local effluent treatment plant, but this particular mill has invested INR 16 million (approx. USD 0.35 million) in its own plant capable of treating 600 cubic metres per day.
The first step is to neutralise the effluent using polymers, followed by treating the waste stream with microorganisms from Novozymes Biologicals, ensuring a 90% reduction in biochemical and chemical oxygen demand. The final step involves passing through a reverse osmosis system for recovery of up to 65% of the water.
The remainder, which has a high level of impurities, is evaporated to leave only solid waste. Currently about 230 cubic metres of water is used per day in the mill processes, and not one drop is released.
Making a difference
Vijayeswari Textiles uses its social and environmental performance to differentiate the company from the competition. The companys speciality is high-quality home textiles supplied to leading US and European retail chains such as Macys in the USA. The current product range includes bed linen, pillow cases, blankets, bedspreads and duvet covers, but new product lines may be introduced in future. High-end bed linen is made using special cotton and fine yarns with high thread counts in the cloth structure. International competition is tough, but the company continues to expand. Founded in 1953, Vijayeswari Textiles is a family-owned, vertically integrated textile mill taking the raw cotton, spinning it into yarn, and then weaving it into finished fabrics. The company employs around 2,800 people and produces about 2.7 million pieces of bed linen annually, which is expected to grow to 3.4 million pieces by 2007. Annual sales turnover is approx. USD 30 million.
The company employs high-calibre textile technologists who run its day-to-day operations. There is a strong commitment to new technology and protecting the environment under the leadership of A.L. Ramachandra, the managing director. He has a Masters degree in microbiology from the USA, so he knows all about enzymes and did not need much convincing to try the biological scouring (bio-scouring) process with Scourzyme L.
Scourzyme L is used for scouring, namely the complete or partial removal of the non-cellulosic components as well as other impurities found in native cotton. Scouring prepares the fabric so that it can be bleached and dyed successfully.
Reasons for switching
Following trials with Scourzyme L in January 2005, the bio-scouring process was adopted for full-scale production in March 2005 and has been used ever since at Vijayeswari. Apart from Scourzyme L for bio-scouring, the amylase Aquazym is used for desizing (starch removal), and the cellulase Cellusoft L for Bio-Polishing in the finishing stage. The only auxiliary used in the bio-scouring system at Vijayeswari Textiles is a wetting agent.
Before switching over to bio-scouring, a traditional alkaline scouring system was used. Vijayeswari Textiles gives a number of reasons for the switch:
- The process is eco-friendly and gives a cleaner effluent.
- Consumers prefer fabric prepared in an eco-friendly way.
- The process is milder and does not alter the structure of the cotton, enabling the retention of natural properties.
- Efficient removal of starch and pectins enhances properties such as wettability and bleachability.
Traditionally, highly alkaline chemicals such as sodium hydroxide are used for scouring. These chemicals not only remove the impurities but also attack the cellulose, leading to a reduction in the strength and weight of the cotton fabric. Furthermore, the resulting wastewater has a high chemical oxygen demand (COD), biochemical oxygen demand (BOD) and salt content.