ZERO LIQUID DISCHARGE
ZLD, Zero Liquid Discharge
Government mandate and environment concerns are the main drivers for zld norms to be adopted.
Three main processs of a ZLD are:
- Efficient and optimally designed ETP: to achieve BOD < 10 and COD < 30 by using mbr or ifas etc.
- Recycling & reuse of water: using membrane technologies like RO, UF, NF etc to treat the water for reuse. This essentially should be a high recovery system. Rejection should be as low as possible so that evaporation requirement is the least.
- Evaporation: the reject from the membrane system should be evaporated and dried using MEE, MVRE etc.
