India is the largest producer of leather and Leather goods. It covers major demands of world requirement. These tannery industries are setup in different parts of India i.e. Tamil Nadu, West Bengal, Utter Pradesh. There are two types of tannery industries namely
 Raw leather processing and.
 Finished leather processing.
In Raw leather processing industries, Raw skin to be processed and convert in to semi finished or Gray Leather by removing soft skin, hair, fat, protein, oils with the help of chemicals mainly with Sodium chlorides and chrome. During this process there is large amount of wastewater generated which is very hazardous and without perfect effluent treatment is not possible to dispose. With existing effluent treatment i.e. with primary and secondary treatment it is not possible to control all parameters as per pollution board limit.