Study on tannery waste treatment

Abstract

This thesis represents an attempt to evaluate the polluting effect of tannery waste and to develop suitable treatment method for the inoffensive disposal of this waste. Characteri3tics of the tannery effluents were determined from extensive laboratory analysis. The high inorganic, organic and toxic pollutants present in tannery waste require treatment before final disposal into natural source of water. It has been observed that low concentration of chromium present in the tannery effluent has no effect on biological treatment process. The suitability of different processes including primary sedimentation, aeration, chemical coagulation, aeration with activated sludge and aeration of tannery waste mixed with domestic sewage, for the treatment of tannery effluent has been evaluated. In this context the optimum detention period for primary sedimentation, the most effective range T pH for alum coagulation of aerateD effluent and the chemical dose required for the desired degree of treatment have been determined. ConclusionE are drawn and recommendations are made for further study.