Low load greywater and municipal wastewater treatment by membrane bioreactor

Abstract

Membrane Bioreactors (MBRs) have become popular in wastewater treatment. Offering excellent permeate quality and eliminating several treatment unit used in conventional wastewater treatment plants due to their special design have made MBRs preferable in reuse applications. Reuse of domestic wastewater and especially greywater, a great part of domestic wastewater, is one of the most widespread reuse applications. Treated greywater can be used for non-potable purposes like toilet flushing, irrigation, washing of vehicles, fire protection, boiler feed water and concrete production. Safe reuse of greywater for nonpotable purposes requires an appropriate treatment and the disinfection of the wastewater in terms of regulations and human concern over health and environment. This study investigates the efficiency of Submerged Membrane Bioreactors (MBRs) in the treatment of low-load greywaters and domestic wastewaters. The quality of the treated greywater samples were evaluated based on the Regulations or Guidelines in Turkey and U.S.A to show the potential of these waters to be reused for non-potable purposes in Turkey and United States. MBR was found to be successful in terms of low-load greywater and domestic wastewater treatment. In the treatment of greywater, the best results were achieved at highest MLSS concentrations. When the obtained results were compared with respect to the Regulations, it was observed that satisfactory results were fulfilled in most of the parameters in greywater treatment. However, despite higher removal efficiencies for fecal and total coliform, permeate concentrations were not satisfactory in terms of microbial quality requirements of some standards..