ABSTRACT

This chapter focuses on iron and steel industry as a whole, critically reviewing the production technology employed for wastes generated in each unit, the role of new technology in decreasing pollution, and the best disposal practices followed. The possible benefits of valuable by-product recovery from the waste streams were explored, so as to enhance water recycling and minimize material consumption. The entire pollution control can be divided into three distinct stages, namely primary, secondary, and tertiary treatments. Initially, the effluent is subjected to physical separation steps like gravity settling, screening, and oil and grease removal to decrease pollutant loadings, followed by coagulation– flocculation. Iron and steel industry, therefore, presents a veritable challenge on account of its vast expanse, numerous potentially polluting units with widely different effluent compositions and characteristics, and high raw material requirement coupled with high output target, all of which make the introduction of new technology difficult.