Sustainable Mining and Metallurgy

The wastewater treatment system of a factory in Beijing was old ，and the removal of _CODCr, ammonia nitrogen, phosphorus and other pollution factors was limited, so it was reformed in basis of the old system. The old intermediate water tank, regulation tank, biochemical tank and sand filter were transformed into anoxic denitrification tank, aerobic+MBR tank, chemical phosphorus removal sedimentation tank and breakpoint chlorination reaction tank, respectively. The optimal reagent concentration of chemical phosphorus removal and inflection point chlorination process was determined. After the transformation, the effluent quality of the system was stable, meeting the requirements of Integrated discharge standard of water pollutants (DB 11/307—2013 ).