水力负荷对反硝化滤池深度脱氮效能的影响

Effect of Hydraulic Loading on Advanced Nitrogen Removal in Denitrification Biofilter

采用反硝化滤池处理城市污水厂尾水,重点考察了水力负荷对其脱氮效能的影响。结果表明:水力负荷对反硝化滤池去除TN影响显著。在C/N值为6.0、水力负荷为3 m3/(m2·h)时,系统出水NH_4^+-N、TN分别为1.66、1.82 mg/L,对其去除率分别为53.43%、91.08%,出水水质可达到《地表水环境质量标准》(GB 3838—2002)的Ⅴ类标准。滤池对污染物的去除主要集中在填料层0~90 cm的区域,对NH_4^+-N、NO-3-N和TN的去除分担率分别为72.73%、95.23%和83.64%。PCR-DGGE分析表明,反硝化滤池中微生物种群丰度和多样性均随填料高度呈现出先增加后降低的趋势;上层与中间层、底层的微生物种群相似度均为85.2%,中间层与底层的微生物种群相似度为80.5%,即反硝化滤池填料层中微生物种属的差异性较小。

A denitrification biofiher plants, the TN and the effect of hydraulic loading was used to treat the effluent of municipal sewage treatment on nitrogen removal was investigated. The results showed that removal was significantly influenced by the hydraulic loading. When the C/N ratio was 6.0 and the hydraulic loading was 3 m3/（m2· h）, the concentrations ent were 1.66 mg/L and 1.82 mg/L, and their removal rates of NHf - N and TN in the system＇ s efflu- were 53.43% and 91.08% , respectively. The effluent quality could reach V class criteria specified in the Environmental Quality Standards for Sur- face Water （ GB 3838 - 2002 ）. The removal rates of NH4 - N, NOr - N and TN in the area with media＇ s height of 0 to 90 cm were 72.73%, 95.23% and 83.64%, respectively. The PCR-DGGE a- nalysis showed that the diversity and abundance of microbial communities increased firstly and then de- creased with the increasing of media＇ s height. The similarity of the microbial communities between the top and the middle/bottom layers was 85.2%, and the similarity of the microbial communities between the middle and the bottom layers was 80.5% , which showed a small difference in microbial communities among the media layers in the denitrification biofiher.