Coke Oven Wastewater Treatment Using on Immersed Membrane Biological Reactor

Effluent from a coke oven by-products plant contains elevated concentrations of organic and nitrogenous compounds from sources including coke oven gas desulphurization, crude light oil recovery, ammonia still operation, coke oven gas condensates, final gas coolers and barometric condensers. The greatest volume of effluent is waste ammonia liquor (WAL), used to scrub coke oven gas to condense tars and moisture and is recycled at a high rate. WAL has high concentrations of BOD5, COD, ammonia, cyanide, sulfide, benzene, phenols and polyaromatic hydrogen compounds (PAHs).With the advent of more restrictive direct discharge standards from the State and categorical standards from the USEPA, it became evident that alternative treatment techniques to the facility's conventional activated sludge treatment system was required.This presentation will review the pilot work that was conducted on an immersed membrane biological reactor (MBR) system, using a prototype of commercially available equipment. The MBR testing results demonstrated that the primary target compounds (BOD5, COD, TSS, oil and grease, ammonia, thiocyanates and phenols) and polyaromatics (benzo(a) pyrene and naphthalene) were removed at rates of 80 to 99 percent and were within direct discharge limitations.The featured work will offer perspective on the treatment of coke oven-based aqueous waste streams containing medium to high strength organics and inorganics via the innovative immersed MBR technology; this will be based on demonstrated technical feasibility, high operational reliability and unique load-variant flexibility of the system.