SUSTAINABLE ENVIRONMENTAL TECHNOLOGIES INCLUDING WATER RECOVERY FOR REUSE FROM TANNERY AND INDUSTRIAL WASTEWATER – INDIAN AND ASIAN SCENARIO

Abstract

World leather sector generates 600million m3 of wastewater per annum. The Asian tanneries contributes more than 350 million m3 of wastewater from the process of 8 to 10 millions tons of hides and skins. Environmental challenges due to depletion of quality water resources and increase in salinity, it has become necessary to control Total Dissolved Solids (TDS) in the treated effluent with water recovery wherever feasible. Adoption of special membrane system has been engineered in many individual and Common Effluent Treatment Plants (CETPs) in India, China and other leather producing countries. The sustainability of saline reject management is one of the major challenges. Conventional tannery wastewater treatment systems include physiochemical and biological treatment to reduce Chromium, BOD, COD and Suspended Solids. To tackle treated effluent with TDS in the rage of 10000 to 30000mg/l, multiple stage high pressure membrane units have been designed and implemented for recovery of water. To reduce the chemical usage and sludge generation in the tertiary treatment, Membrane Bio-Reactor (MBR) has been adopted which replace secondary clarifier and sophisticated tertiary treatment units such as Reactive Clarifier, Ultra-filtration (UF), etc. Commercial scale high-tech membrane systems have been implemented in many locations for the capacities ranging from 500 to 10000m3/day. Recent applied R&D on the environmental protection techniques with focus on water-recovery for reuse, salt recovery, marine disposal of saline reject with proper bio-control system, etc. are dealt in this novel technical paper.

Keywords

• Effluent Treatment System
• Environment
• Sustainability
• Water Recovery