Dyeing is one of the highly polluted industrial process, researches have been conducted to reduce the impact of Wet process, reduce the water and energy use. At present the wet process industries (Knitted) are having soft flow dyeing machines with the material liquor ratio with the range of 1:4 to 1:10.
The issue with the wet process is effluent water treatment, the cost of treating the effluent water is significantly high and the hazardous solid wastes generated out of all treatment is waiting to get disposed in a proper way which is again an additional cost burden to the dyers!
Recently Nike took an initiative towards the “Waterless dyeing”, at their facility in Taiwan.
Their news report claims that, “Today, an estimated 100-150 liters of water is needed to process one kg of textiles and industry analysts predict that over 39 million tons of polyester will be dyed each year by 2015”.
Nike had invested in Dutch start-up, DyeCoo Textile Systems, a company that invented a technology to replace water, normally used for dyeing, with recyclable CO2, reducing energy use and eliminating the need for added chemicals in the process – Waterless Dyeing!.” The DyeCoo waterless process is currently more costly than its traditional water counterpart, but it reduces:
- Energy use by 63%
- Dyeing time by 40%
- Water use by 30 liters per t-shirt
The Color Dry – Revolutionary Water Free Dyeing Process
The water free dyeing uses “liquid CO2” as a medium for dye the fabric. During the process Heat and Pressure change the Liquid CO2 into Super Critical Fluid CO2 and infused through the fabric beam and makes the fabric dyed. After dyeing the super Critical Fluid with Dye is send to a separator and the Fluid is evaporated and the excess dyes and stuffs separated. By reducing the pressure the Liquid CO2 is recovered up to 95% and stored for re use. This is one of the biggest shift and Positive Black swan in the Textile wet process industry.
Mr. Girish of Pacific Ventures, shared an information that, In India,Tirupur, a Project has been carried out by Mr. Kesavan of Sivasakthi Textiles Process, with the support of Dystar and SASMIRA. Many leading retailers have approached him to carry out commercial operation. Initially this has been tried on Polyester and research is on for cotton dyeing. soon we will have the pollution issues sorted out in waterless dyeing.
Source: Nike’s Press Release & 2 Degrees Network