Treatment efficiency and membrane fouling of a lab-scale Anaerobic Membrane Bioreactor treating dilute municipal wastewater

摘要

The study aims to investigate the application of anaerobic processes coupled with membrane filtrationfor treating dilute municipal wastewater in Hanoi city (COD:100-300mg/l, BOD5: 60-180 mg/L, NH4-N:14-35 mg/L). A lab-scale Anaerobic Membrane Bioreactor (AnMBR) with flat sheet, polyvinylidenefluoride membranes (nominal pore size=0.4μm; total filtration area=0.09 m2) was operated at differentHRTs (48 hours, 36 hours, 24 hours, 12 hours, 8 hours and 6 hours) for 560 days with COD loadingrates up to 1.58 kg/m3.d at room temperatures (from 10-39°C). The biomass accumulated reached8gMLVSS/L by the end of the operation period. No noticeable volatile fatty acids (VFAs) were detectedregardless of HRT variations. The AnMBR system maintained relatively constant TransMembranePressure (TMP). The results showed that physical retention of organics by the MF membrane played asignificant role in achieving good and stable performance (removal rate for TSS: 98-100%, COD:70-90%, and BOD: 72-88%) at wide range of temperatures.