厨余发酵液与乙酸钠作碳源的脱氮与膜污染对比

Denitrification and Membrane Fouling Using Kitchen Waste Fermentation Liquid and Sodium Acetate as Carbon Source

采用厌氧—好氧—膜生物反应器(A/O-MBR)处理西安市某校园生活污水,分别以厨余发酵液和乙酸钠为外加碳源,考察了反应器的脱氮性能,并探讨了其膜污染状况。结果表明:在31 d的运行中,两种条件下对NH+4-N、TN和COD的平均去除率分别为98.2%、78.5%、95.7%与96.7%、76.0%、93.9%;以厨余发酵液为碳源的反硝化速率为12.44 mg NO-x-N/(g VSS·h),高于以乙酸钠为碳源的8.62 mg NO-x-N/(g VSS·h)。此外,两种条件下厌氧池、好氧池、膜池的EPS与SMP浓度之和分别为98.58、81.08、79.74 mg/g VSS与76.12、59.93、55.22 mg/g VSS,这说明以厨余发酵液作为外碳源时可能更易导致膜污染。

The anaerobic/oxic - membrane bioreactor （ A/O - MBR） process was used to treat the sewage from a campus in Xi＇ an City. Denitrification performance and membrane fouling of the process were investigated by using kitchen waste fermentation liquid and sodium acetate as additional carbon source respectively. The results showed that in the operation of 31 d, the average removal rates of COD, TN and NH4＋ - N, in kitchen waste fermentation liquid system were 95.7%, 78.5% and 98.2% respec- tively, and in sodium acetate system were 93.9% , 76.0% and 96.7% respectively. The specific deni- trification rate of kitchen waste fermentation liquid system was 12.44 mgNOx - N/（ gVSS · h）, and that of sodium acetate system was 8.62 mgNOx- - N/（ gVSS · h）. In addition, for the two systems, the sums of SMP and EPS in anaerobic tank, aerobic tank and membrane tank were 98.58, 81.08, 79.74 mg/ gVSS and 76.12, 59.93, 55.22 mg/gVSS respectively, which indicated that using kitchen waste fermentation liquid as additional carbon source might be more likely to cause membrane fouling.