改进型曝气生物滤池对生活污水氮去除的影响

Effect of modified biological aerated filter on nitrogen removal of domestic wastewater

采用下向流中部曝气的运行方式,对生活污水进行了处理,考察了气水比、有机负荷对生物滤池的去除效果及其沿程生化特性。结果表明:水力停留时间为8 h,气水比为10∶1条件下可获得最佳的处理效果,COD、TN和NH4+-N的平均去除率分别为92.5%、48.6%和69.4%。进水有机负荷增加,COD和NH4+-N的去除率下降,TN的去除率可达60.5%。结合理论分析,对脱氮性能进行了探讨。

The aeration system installed in the middle of BAF was used for domestic wastewater treatment.Gas-to-liquid ratios、organic loadings and microbes along the reactor of BAF were investigated.Results indicate that the good performance of BAF can be achieved at hydraulic retention time 8 h,gas-to-liquid ratio 10∶1,the average removal rates of COD,TN,NH＋4-N in optimal stage are 92.5%,48.6% and 69.4%,respectively.Higher organic loadings result in lower efficiencies of COD、NH＋4-N removal,but the efficiency of TN removal increases to 60.5%.Based on experimental results and theoretical analysis,the mechanism of TN removal was probed.