Study On Performance And Process Parameters Of Anaerobic Baffled Reactor (ABR) In Treating Low-strength Wastewater

Anaerobic Baffled Reactor(ABR), which has been successfully applied in high-strength organic wastewater treatment with good progress, is a new type of high-efficiency anaerobic reactor, and its application and research in treating low-strength wastewater has also been paid more and more attention.In this paper, two six-apartment ABR reactors which are the same in design and almost same in volume (ABR1:15.4L;ABR2:16.9L) were used in the study and compared. The start-up, performance and steady identity, process parameters(HRT, OLR) and granular sludge characteristics were studied at 35C.The result showed that ABR has strong adaptability to shock loading conditions. high organic(COD) removal was gained and the system was in good operating steady state. All the HRTs tested resulted in 80%~90% COD removal when the influent CODc_r was 500mg/L and the effluent CODc_r was 50~70mg/L.when the influent CODc_r was 700mg/L and 1000mg/L, 85%~95% of the influent CODc_r was removed at a HRT of 12h, 9h and 6h, at an HRT of 3h, the ABRs showed a lower COD removal but still more than 70% influent CODc_r was removed.It was shown that OLR and HRT were two important process parameters affecting the operating performance of ABR. It apparent that the effect of decreasing HRT(at constant feed concentration),or increasing feed concentration(at constant HRT) both decreased the COD removal efficiency.However the effect of decreasing HRT is more severe. it is very important to choose appropriate OLR and HRT.Analysis of VFA content of the compartments showed that VFA was increasing at first to a high point and decreased later. For the pH, the phenomenon was opposite. In general, acidogenesis dropped back and with decreasing of HRT, resulting in the backing of VFA and pH increase.The anaerobic granular sludge characteristics and components indicate sludge quality. The anaerobic granular sludge characteristics were observed. For low strength wastewater, the anaerobic granular sludge was less in radius and looser compared with high strength wastewater. It is necessary for deep research.