Overview of treatment methods of tannery wastewater

Abstract

Poor waste management, particularly the wastewater from tanning procedures, has led to significant environmental issues and eventually harmed human health. Most tanneries still use traditional production techniques and release toxic heavy metals into the sewage system without properly treating it. In this regard, chromium (Cr) present in the effluent from tanneries is one of the toxins that are carcinogenic, mutagenic, and teratogenic. This review paper summarized the research conducted on tannery effluent treatments by briefly covering the techniques for treating Cr metal and its removal efficiency. Further, future aspects and proposals have also discussed. Researchers have used various treatment methods such as activated sludge, chemical precipitation, coagulation, coagulation-aided sedimentation, membrane filtration and AOP (Advanced oxidation process). A review of the literature showed that the level of hazardous Cr has been significantly reduced to low amounts by using several physico-chemical treatment methods. This review paper will be helpful to practising engineers in the selection of proper methods for treating tannery effluent and researchers in conducting their future studies.