Textile dyeing industries need huge quantity of water for textile dyeing, which they normally pump out repeatedly from the ground or natural water sources resulting in depletion of ground water level.
In the dyeing process textile industries generate huge quantity of toxic effluent containing colours, sodium sulphate, sodium chloride, sodium hydroxide and traces of other salts. These are generated after dyeing and after washing of garments / fabrics. After dyeing the waste water produced is called Dye Bath water and after washing the waste water generated is called wash water. Dye Bath contains higher solids in the range 4-5% whereas wash water contains only 0.5-1% solids. Treatment of this type of Waste Water is complex because apart from high BOD and COD levels, such Waste Water has colour, which is difficult to treat.