Anaerobic treatment of municipal wastewater with a staged anaerobic fluidized membrane bioreactor (SAF-MBR) system

摘要

A laboratory-scale staged anaerobic fluidized membrane bioreactor (SAF-MBR) system was used to treat a municipal wastewater primary-clarifier effluent. It was operated continuously for 192days at 6-11L/m ~2/h flux and trans-membrane pressure generally of 0.1bar or less with no fouling control except the scouring effect of the fluidized granular activated carbon on membrane surfaces. With a total hydraulic retention time of 2.3h at 25°C, the average effluent chemical oxygen demand and biochemical oxygen demand concentrations of 25 and 7mg/L yielded corresponding removals of 84% and 92%, respectively. Also, near complete removal of suspended solids was obtained. Biosolids production, representing 5% of the COD removed, equaled 0.049g VSS/g BOD _5 removed, far less than the case with comparable aerobic processes. The electrical energy required for the operation of the SAF-MBR system, 0.047kWh/m ~3, could be more than satisfied by using the methane produced.