Leather Manufacturing Wastewater Characterization and Cleaner Production Options

Abstract

This study analyzes physicochemical characteristics of wastewater from all of leather manufacturing processes, and compare pollutants load released from goat and cow hides manufacturing processes. Results of experimental work for characterization of wastewater released from two local tanneries are presented. By analysis of pH, chemical oxygen demand (COD), total solids (TS), total dissolved solids (TDS), total suspended solids (TSS), chloride, ammonia (NH3) and chromium. Characterization of these process effluents was done in order to identify the waste generation rate and quantities discharged. Highest pH value measured was about 13.5 in liming process while the lowest was about 3 in retanning effluent. COD of liming-hair removal effluent exceeded 160000 mg/l, which contributed to more than 50% of total COD. Analysis of chromium tanning effluent showed that hexavalent chromium concentration was 3.2*10-4 mg/L, which is below the permissible limit. Future research work for management of chromium containing wastewater in this industry is important. Financial burden from ever-tightening “Israeli” occupation’s legislations on leather manufacturing industry and the associated environmental impacts shall motivate research work for better exhaustion and uptake of chromium.