Performance of Hybrid Anaerobic Baffled Reactor in Treating Wastewater with High Strength of Suspended Solids

Abstract

Operating anaerobic reactors at high strength of suspended solids (SS) can lead to instability and high concentration SS in effluent. To overcome these limitations, anaerobic baffled reactor (ABR) was modified by enlarging the first compartment and filling carriers in up-comer regions to produce the hybrid anaerobic baffled reactor (HABR). Consequently, more favorable conditions were created in the first compartment such as longer hydraulic retention time, better settlement characteristics and longer cell retention time. The carriers improved the retention of SS and cell across the reactor. An ABR with enlarged first compartment (no carriers) was used to compare the performance. The influent COD and SS concentrations were increased from 700 and 300 to 7000 and 2800 mg/L, respectively. After a 187 days operation, with influent COD and SS of 7000 mg/L and 2800 mg/L, both HABR and ABR kept an efficiency of higher than 94.0% in treating COD and an efficiency of higher than 93.0% in removing SS. Higher removals of COD and SS were observed in the HABR than in the ABR. At the same time, performance of HABR was more stable than that of ABR.