磁混凝沉淀-反硝化滤池用于污水厂准Ⅳ类标准提标改造

Application of magnetic coagulation sedimentation-denitrification filter for upgrading and reconstruction of sewage treatment plant to meet quasi class Ⅳ standard

山东省某污水厂原处理工艺采用多级多段AO-混凝沉淀过滤工艺,污泥处理采用重力浓缩-机械脱水工艺,出水水质符合GB 18918—2002《城镇污水处理厂污染物排放标准》一级A标准。原污水厂存在一期脱水机老化,二期进水含砂量大,COD质量浓度无法全年稳定在30 mg/L以下,TN去除率低等问题。为解决相关问题,本次提标改造工程在二期新增固液秒分离机,把原高密度沉淀池改造为磁混凝沉淀池,新建反硝化滤池、紫外线消毒池和巴氏计量槽,使得TN、COD、TP去除率显著提高,除TN外,其余出水水质指标均达到GB 3838—2002《地表水环境质量标准》中的Ⅳ类标准。

A sewage treatment plant in Shandong province adopted multi-stage and multi section AO-coagulation sedimentation filtration process to treat water,and used gravity concentration-mechanical dehydration process to treat sludge,the effluent water met the requirement of grade 1 level A in GB 18918—2002 Discharge standard of pollutants for municipal wastewater treatment.In order to solve the problems in the original sewage treatment plant,such as aging of the first-stage dehydrator,large sand content of the second-stage influent,unable to keep COD mass concentration below 30 mg/L throughout the year,low removal rate of TN and so on,solid-liquid separator was added in the second phase of the upgrading project,the coagulation sedimentation tank was changed to magnetic coagulation sedimentation tank,and the denitrification filter,ultraviolet light disinfection tank,and paseur metering tank were built.Through the reconstruction,the removal rates of TN,COD and TP increased significantly,all the quality indicators except TP of the effluent water met the requirement of classⅣin GB 3838—2002 Environmental quality standard for surface water.