青岛李村河污水处理厂类Ⅳ类标准提标扩建工程设计

Design of Quasi ClassⅣDischarge Standard Upgrading and Expansion Project in Qingdao Licunhe Wastewater Treatment Plant

青岛李村河污水处理厂原设计规模25×10^(4)m^(3)/d,为满足李村河流域污染物削减及生态补水需求,四期工程需扩容至30×10^(4)m^(3)/d,同时将出水标准由一级A标准提高至地表水Ⅳ类标准(总氮≤15 mg/L除外)。提标扩建工程采用原厂减量分流扩容的建设方案,污水处理采用改良Bardenpho+MBR工艺,原厂分流后出水增设高速气浮工艺,与MBR出水一并经臭氧氧化及消毒后排放。另外,为减少邻避效应,新建厂区采用半地下全覆盖建设方式。工程建成运行以来,在进水浓度冲击较大的情况下,各项出水指标均优于设计指标,同时为李村河上游提供了最大20×10^(4)m^(3)/d的生态补水,取得了良好的生态效益和社会效益。

The original design scale of Qingdao Licunhe wastewater treatment plant is 25×10^(4)m^(3)/d.To meet the requirements of pollutant reduction and ecological water supplement in Licun River basin,the scale of phaseⅣproject has to expand to 30×10^(4)m^(3)/d,and the discharge standard should be raised from first level A discharge standard to classⅣsurface water standard(except for total nitrogen no more than 15 mg/L).The upgrading and expansion project adopted the construction scheme of capacity reduction,wastewater diversion and capacity expansion of the original plant.The modified process consisting of Bardenpho and MBR was adopted in the expansion project.A high-speed air floatation process was added for treating the effluent from the original plant,and it was oxidized by ozone and disinfected together with the effluent from the MBR before discharge.In addition,the construction method of semi-underground full coverage was adopted in the new plant to reduce the“not in my backyard”conflict.Since the completion and operation of the project,the effluent indexes were better than the design indexes under the condition of large influent shock load.In the meantime,the project provided the maximum 20×10^(4)m^(3)/d of ecological water supplement for the upstream of Licun River,which achieved good ecological and social benefits.