Biofilm/membrane filtration for reclamation and reuse of rural wastewaters

To cost-effectively meet water quality and quantity requirements for rural areas, the objective of this research was to evaluate the performances of a three-stage process of anaerobicoxic-anoxic biofilm filtration (AOBF) and membrane filtration (MF) processes and to assess the potential for reclamation and reuse of blended wastewater contained domestic wastewater, black water, and landfill leachate. The AOBF process at < LV 30 m/day showed good removal results of > 90% for conventional pollutants (> 75% for COD) and > 70% for nutrient. Influent step-feeding with 0.8Q into filter bed 1 and 0.2Q into filter bed 2 achieved denitrification efficiency of 5-10% higher than without step feed. Efficiencies of plate membrane removal were greater than 90% for COD and more than approximate 75% for nutrients and heavy metals, respectively. The AOBF/MF system showed excellent removal results of > 90-95% for soluble nutrients as well as nonsoluble fractions such as TSS, particulate COD. The effluent of AOBF/MF system met the reuse standard for industrial and agricultural water, while effluent of AOBF met the standard for the effluent quality of wastewater treatment plants. These results indicate that the AOBF/MF system was suitable for rural integrated wastewater treatment by achieving cost-effectively an effluent quality able to be used for industrial, agricultural and water bodies recharge purposes.