Pilot-scale Study on the Treatment of Domestic Sewage by Periodic Anaerobic Baffled Reactor at Low Temperature

In order to investigate the operation effect of periodic anaerobic baffled reactor(PABR) for the treatment of domestic sewage,the start-up of PABR and treatment performance were studied. Results showed that the PABR which operated at low temperature of 3~18 ℃ can be started-up successfully. The hydraulic retention time(HRT) was gradually decreased(20h-12h-12h)at a constant influent COD concentration of 180~350 mg/L. The average removal rate of COD was 75%,COD of the treated effluent was between 60 and 90 mg/L,with volume organic loading of 0.7 kg COD/(m3·d),pH of effluent was about 7.3 and the concentration of volatile fatty acid(VFA) was 160 mg/L,alkalinity concentration was 280 mg/L when the reactor was started successfully. In addition,most of the COD in wastewater was removed in the first two compartment of the PABR,with COD removal in the first two compartments up to 53% and 40% of the total COD removal respectively. MLSS,MLVSS,settle ability and activity in the former two compartments were better than that in the latter two ones. Therefore,PABR can be set up successfully and run smoothly when treating domestic sewage under low temperature condition.