Study on wastewater treatment by integrated plate membrane bioreactor

In membrane bioreactor (MBR) technology, the membrane fouling is the main problem. In this study, the integrated plate MBR was used to treat the municipal wastewater. It is ascertained that the critical flux of polyethersulfone(PES) membrane with MWCO of 70,000 Da is 43.6L/m².h. And the membrane was made by a domestic firm. The tests revealed that in the operation process of a MBR, membrane fouling is inevitable. It was found there is an exponential function relation between the initial flux and the membrane pressure increasing velocity, i.e. d(ΔP)/dt = 0.0054e^(0.1145×J). The initial flux choosing has important effect on the system stable operation. Adoption the initial flux under critical flux is an important condition for the system to operate stably with longer time. The experiments indicate that the effluent COD, ammonia nitrogen and SS of the integrated plate MBR completely meet the class A demands of “Discharge standard of pollutants for municipal wastewater treatment plant” (GB18918-2002) of China. The effluent can be used as reclaimed water directly.