纤毛状生物膜脱氮除磷工艺调试研究

Pilot-scale experiment on nitrogen and phosphorus removal by CNR process

纤毛状生物膜脱氮除磷工艺(CNR)是一种高效的生物脱氮除磷工艺。好氧池中纤毛状生物膜填料的添加,固化了大量世代时间长的硝化菌,提高了硝化反应速度,而且成功地解决了好氧段硝化菌与聚磷菌的泥龄矛盾。通过对天津某污水处理厂进行CNR工艺中试,得出结论如下:填料比表面积大,微生物附着量高达1350～1500g·m-2;填料容易挂膜、脱膜,无堵塞现象,更不需要反冲洗,维护管理简单;填料上形成的生物膜中,微生物体系稳定,种群丰富,微生物相包括钟虫(vorticella)、轮虫(rotaria)、表壳虫(arcella)、吸管虫(tokophrya)等;采用CNR工艺对污水处理,常规项目的去除率均达到80%以上,出水水质除总氮达到一级B标准,其他均达到《城镇污水处理厂污染物排放标准》(GB18918-2002)的一级A排放标准。

Cilium Nutrient Removal Process（CNR）is a novel technology that is effective for simultaneous nitrogen and phosphorus removal. The cilium-shaped media is fixed in aerobic tank and nitrobacteria with long generation time are attached to the media. Therefore,nitrification effect is strengthened greatly. Furthermore,the contradiction of sludge age between nitrobacteria and PAOs is resolved successfully. A pilot-scale experiment was carried out in a sewage treatment plant in Tianjin. The results show that the biomass attached to the media is up to 1 350 g·m^-2 due to the larger specific surface of the media. It＇s easy for the biofilm to form and detach from the cilium^-shaped media,so no blockage is observed and maintenance is simple without back washing. In biofilm formed in cilium^-shaped media,microorganism consortium is very stable and has high diversity,and many protozoon and metazoan are included,such as vorticella,rotaria,arcella,tokophrya and so on. After the treatment by CNR process,the removal efficiency of routine items all reach more than 80%. All of the indexes meet the first level A criteria specified in the Discharge Stan-dard of Pollutants for Municipal Wastewater Treatment Plant （GB 18918—2002） except that TN meets the first level B criteria.