Influence factor and removal effect of SMBR process to treat soybean sauce wastewater

摘要

Based on the practical engineering and aimed at the difficulties in treating soybean sauce wastewater, a series of experiments were conducted to investigate effects of HRT, DO, pH and MLSS on the effluents qualities. According to the optimum operation conditions for SMBR (Submerged Membrane bioreactor), the efficiencies of SMBR and two-stage SBR-air floating process were compared. Satisfactory efficiencies in SMBR were obtained worked with HRT at 10h, DO at 2.5mg/L, pH at 7.8 and MLSS at 8～9g/L. In this way, the effluent met the national first grade discharge standard steadily and avoided the nonsynchronous degradation of COD and color. Analysis of the biophase in SMBR indicated that zoogloea and protozoan contribute to a more intricate biosysteM than SBR, which provided SMBR a better ability in resisting impulse loading and resulted stable treatment efficiency both at high and low loading.