双层滤料生物滤池去除城市污水中COD_(Cr)和NH_3-N的试验研究

Experimental investigation of removal of COD_(Cr) and NH_3-N from urban sewage by using biological filter bed with double-layer filter material

研究炉渣-沸石双层滤料曝气生物滤池处理城市污水中CODCr和NH3-N的去除效果,试验结果表明:滤池中两种滤料显示出良好的互补性,滤池对CODCr和NH3-N的去除率稳定;污染冲击负荷对滤池的去除效率影响较小;最优滤池运行参数为气水比2∶1,水力停留时间12 h,反冲洗周期5-6 d;反冲洗后需稳定12 h滤池的处理效率方能恢复到80%以上.

The result of removal of CODcr and NH3-N from urban sewage was experimentally investigated by using biological aerated filter bed with double filter material of slag and zeolite. The experimental results showed that there was good mutually complementary action between two filter media, the removal rate of the filter bed was constant, and the influence of pollution shock load on the removal efficiency was less. The optimum technological parameters were： gas/water ratio - 2 ： 1, hydraulic retention time - 12 h, and optimum backflush interval is 5-6 days. The removal rate would resumed to the optimal one after backflush about 12 h.