Zero Liquid Discharge System for the Tannery Industry—An Overview of Sustainable Approaches

The tannery industry is characterized by the consumption of a large quantity water, around 30–40 m3 for processing 1000 kg hide or skin. This amount becomes wastewater, containing about 300 different chemicals, mainly refractory organic compounds, with high chemical oxygen demand (COD), total dissolved salts (TDS), chromium, and evolution toxic gases, such as ammonia sulfides, etc. remaining tanning chemicals are released effluent having resistance against biological degradation, becoming serious environmental issue. Usually, end-of-pipe treatment not sufficient to meet concerns issues. In terms cleaner production options, redesigning existing procedures alternate additional techniques, which “supports resource recovery no added chemicals”, expected give sustainable solution management effluent. Zero Liquid Discharge (ZLD) system serves ensure zero water emission, well facilities recycling, recovery, reuse treated wastewater using advanced cleanup technology. international scenario shows implementation ZLD thanks pressure from regulatory agencies. consists pre-treatment conventional physicochemical treatment, tertiary softening effluent, reverse osmosis (RO) desalination, thermal evaporation saline reject RO separate salts. By adopting this system, reduced. Moreover, also effective in disaster mitigation areas where strong economic actor. With review, we aim an outlook current framework.