Treatment of anaerobic effluent from synthetic soybean further processing wastewater and sludge reduction by MBBR-SA process
MBBR-SA工艺处理模拟大豆深加工废水厌氧出水及污泥减量化

According to properties of anaerobic effluent from the soybean further processing wastewater, MBBR-Settling-Anaerobic (MBBR-SA) system was designed and operated with the synthetic soybean wastewater which with COD of 1 350~1 851 mg/L, TN of 45~73 mg/L and TP of 35~55 mg/L, the effects of COD removal and nitrogen removal were investigated. During 70 days operation, a good performance was shown in the MBBR-SA system when the optimal hydraulic retention time (HRT) and reflux ratio were 1.68 d and 0.75, respectively. The treated effluent levels of COD, TN, NH4+-N remained below 91.5 mg/L, 12.4 mg/L, 11.4 mg/L, respectively and met Class II standard, Class II standard and Class I B Standard of Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant, respectively. The average removal efficiencies of COD, TN and NH4+-N in effluent were 96.0%, 87.4% and 88.3%, respectively under the optimal operation conditions. The residual sludge was not discharged and the observed sludge yield was 0.13,which reduced by 43.5% than MBBR. Remarkable on-site sludge reduction was realized by MBBR-SA system.