Biological Treatment of Tannery Wastewater for Sulfide Removal A ReviewAuthor(s): Varsha Midha and Apurba Dey
The transformation of hides into leather is usually done by using tanning agents and a highly turbid, colored and foul smelling wastewater is generated in the process. The major components of the effluent include sulfide, chromium, volatile organic compounds, large quantities of solid waste, suspended solids like animal hair and trimmings. The various components present in the effluent affect human beings, agriculture and livestock besides causing severe ailments to the tannery workers. The environmental protection regulations stipulate that industries are not allowed to emit sulfide and chromium in the wastewater. Thus removal of sulfide and chromium from the wastewater is very important. A number of researchers worked on the removal of sulfide and chromium from the wastewater streams, but little has been reported on the sulfide removal from the tannery wastewater. In this paper, characteristics of tannery wastewater and methods of sulfide removal have been discussed.