冷冻固定化硝化菌去除废水中氨氮的研究

采用聚乙烯醇(PVA)循环冷冻法制备固定化硝化菌颗粒，经活化后在颗粒填充率为9％的三相流化床中进行氨氮废水处理试验。处理低浓度氨氮有机废水(NH3-N质量浓度为75mg／L．COD约为400mg／L，水力停留时间为4h)时，NH3-N去除率约为90％，COD、TIN的去除率可达82％和60％左右；处理高浓度氨氮废水(NH3-N质量浓度450～500mg／L，水力停留时间为20h)时，NH3-N去除率在98％以上，氨氧化产物中NO2^--N质量分数在95％以上，为亚硝酸盐反硝化提供了有利条件。用该法制成的硝化菌颗粒寿命在3个月以上。

Research on Removal of Ammonia Nitrogen from Wastewater by Frozen Immobilized Nitrifying Bacteria

The immobilized nitrifying bacteria pellets were made by iterative PVA freezing and thawing. The cultivated pellets were used to treat NH3 - N wastewater in a biological fluidized bed reactor (BFBR) in which the volume fraction of the immobilized pellets was 9% . In the treatment of low concentration wastewater with 75 mg/L of influent NH3 - N concentration, 400 mg/L of influent COD and 4 h of reaction time, the removal rate of NH3 - N reached about 90% and those of COD and TIN reached about 86% and 60% respectively. While the influent NH3 - N concentration was increased to 450 - 500 mg/L and the reaction time prolonged to 20 h, the removal rate of NH3 - N was above 98 % and the mass fraction of NO2- - N in the NH3 - N oxidation products was more than 95%, which benefited the denitrification of nitrites. The life of nitrifying bacteria pellets cultivated by the process was more than 3 months.