A PROCESS FOR ACHIEVING ZERO INDUSTRIAL LIQUID DISCHARGE FOR TEXTILES DYEING WASTEWATER

摘要

A process for achieving zero industrial liquid discharge for textiles dyeing wastewater, the brine obtained from the wastewater is treated for re-use in the textile dye baths, said treatment comprising the steps of subjecting the brine to biological processes with decolourant resin filter to reduce COD and colour to 1.5 mg/1 and 700 Pt CO units, respectively; dosing with sodium hypochlorite for further reduction of input colour to the resin filter to 100 Pt CO units; feeding ultrafiltration permeate into the resin filter to reduce the resin regeneration volume; separately collecting the decolourant resin and softener regeneration liquour and dosing with lime soda for removal of hardness and colour in the BDTRF liquour; reducing the volume of brine with an additional stage RO; and increasing salt concentration and reduction in volume of brine using MVRF-E.