中文摘要：

为了解决BAF工艺除磷效果不佳的问题，探讨了前置投加PAC对胜利油田某污水厂BAF工艺处理效能、微生物活性及种群结构的影响。前置投加PAC能有效提高BAF处理效能，当PAC投加量在65～80mg／L时，对COD的去除率在85％以上，对NH3-N及TP的去除率分别在95％和75％左右。此时，CN池滤料表面生物膜的耗氧速率为75．32mgO2／（gMLVSS·h），CN池反冲洗污泥的耗氧速率为78．19mgO2／（gMLVSS·h）；在外加碳源的基础上，CN池反冲洗污泥的比硝化速率为1．48mgNH3-N／（gMLSS·h），DN池反冲洗污泥的最大反硝化速率为15．84mg/（gMLVSS·h）。镜检发现滤料表面附着有成熟的生物膜，存在轮虫、钟虫、累枝虫、喇叭虫等多种微生物。因此，投加PAC对微生物活性及种群结构没有影响。

英文摘要：

In order to address the poor phosphorus removal effect in the BAF process, the influ- ence of PAC addition on the treatment efficiency, microbial activity and community structure in the BAF process used in a WWTP in Shengli Oilfield was investigated. The addition of PAC could effectively im- prove the efficiency of the BAF process. When PAC dosage was between 65 mg/L and 80 mg/L, the re- moval rates of COD, NH3 - N and TP were above 85% , about 95% and 75% respectively. The oxygen uptake rate of the biofilm on the surface of CN tank media was 75.32 mgO2/（ gMLVSS · h）, and the ox- ygen uptake rate of backwash sludge in CN tank was 78.19 mgO2/（ gMLVSS · h）. On the basis of addi-tive carbon source, the specific nitrification rate of backwash sludge in CN tank was 1.48 mgNH3 - N/ （gMLSS · h）, and the maximum denitrification rate of backwash sludge in the DN tank was 15.84 mg/ （gMLVSS · h）. The scanning electron microscopy showed that the mature biofilm was attached to themedia surface, in which existed Rotifera, Vorticellidae, Epistylidae, Stentor and other microorganisms. Thus, the addition of PAC had no effect on microbial activity and community structure.