MBR Technology For Coke Oven Effluent Treatment

A ten-month MBR demonstration pilot was undertaken to treat effluent from the coke oven by-products plant at a Steel Production Facility in India.The plant was fed with real waste water from the coke oven by-product plant at the existing facility. High removal rates for organic and nitrogenous compounds were achieved using a simple anoxic – aerobic MBR configuration. Achievable removal rates for BOD5. COD, TKN, Phenols, Cyanides and Thiocyanates observed were >99%, >84%, >80%, >99%, 50% and >90% respectively. Appropriate equalization and control of process conditions were identified as essential for the stable performance of the system.Membranes operated stably with fluxes averaging approximately 17 L/m2/h and peaking at 34 L/m2/h successfully demonstrated. Little membrane cleaning efforts were required and cleaning of the membranes at the end of the study indicated no irreversible loss of permeability throughout the study.MBR technology proved to be a reliable solution to provide superior effluent quality compared to conventional biological treatment systems. The reliable retention of biomass of the MBR allowed for easy and stable operation of the biological system (no unwanted biomass carry-over), producing treated effluent suitable for downstream advanced treatment. Major benefits for the use of MBR technology are when stringent effluent criteria have to be met or reuse of the water after appropriate downstream treatment, such as reverse osmosis or activated carbon filtration, is targeted.