Recently, the Tamil Nadu government officials inspected the zero-liquid discharge (ZLD) plants at various industries on Sipcot premises at Perundurai.
About Zero Liquid Discharge (ZLD)
- Zero Liquid Discharge (ZLD) is a cutting-edge wastewater treatment process developed to completely eliminate all liquid discharge from a system.
- The goal of a zero liquid discharge system is to reduce the volume of wastewater that requires further treatment, economically process wastewater and produce a clean stream suitable for reuse.
- The ZLD System removes dissolved solids (mainly salt) from the wastewater and returns pure water to the process.
- Reverse osmosis (membrane filtration) is used to concentrate pre treated waste stream and return the clean permeate to the process, funnel the reject to an evaporator, and send the evaporator concentrate to a crystallizer or spray dryer.
- The condensate from evaporator also returned to the process.
- In order to prevent pollution of River water and ground water Tamil Nadu Pollution Control Board (TNPCB) has made the ZLD system mandatory for all the highly polluting industries which uses considerable amount of salt in the process and consumes huge quantity of water.
- The ZLD system ensures recovery of water & salt from the waste water thus preventing pollution of River / ground water.
