Zero Liquid Discharge Scheme in a Common Effluent Treatment Plant for Textile Industries in Tamilnadu, India

Perundurai Common Effluent Treatment Plant is one of the front runners in implementing 'Zero Liquid Discharge' concept in the treatment and management of effluents from a cluster of textile processing industries. The effluent is segregated into low TDS (< 2100 mg/L) and high TDS (> 2100 mg/L) streams at the individual member units itself and sent to treatment plant through separate pipelines. Low TDS effluent is subjected to primary, secondary and tertiary treatments to recover 77.7 % of the effluent for reuse by the member units. High TDS effluent is treated through Multiple Effect Evaporators and solar evaporation pans or salt recovery plant and converted into solid wastes. Out of a total pollution load of 48 kg/m³ of effluent, only 6.0 kg/m³ is removed through the treatment and the remaining is transferred to solid wastes. The capital investment to implement this scheme comes to Rs. 67,018/m³ with recurring expenditure of Rs. 90/m³.