Abstract: With the increasingly strict requirements of environmental protection, higher requirements for the effluent quality of urban sewage treatment plants were put forward. The originally designed effluent of Changtu sewage treatment plant was the first class B discharge standard of GB18918—2002 standard for pollutant discharge of urban sewage treatment plants, whose treatment process was single and process flow was not perfect. Moreover, the project was located in a cold area, resulting in unstable effluent quality, which needed to be urgently upgraded. Based on the current situation and main problems of the proposed project, the original biochemical process was upgraded from A/O process to A2/O process. In addition, the “coagulant sedimentation + fibber rotary plate filtration” advanced treatment unit and disinfection process were added. The research results show that after the transformation, the operation of the sewage treatment system is stable, the treatment effect is good, and the effluent quality can meet the first class A discharge standard of GB18918—2002 standard for pollutant discharge of urban sewage treatment plants. The proposed project practice can be used for reference to upgrade and transform wastewater treatment plant in cold area.

Key words: environmental engineering, sewage treatment plant, bid upgrading, A2/O process, advanced treatment

摘要： 随着环保要求日益严格，对城镇污水处理厂出水水质提出了更高的要求。昌图污水处理厂原设计出水为GB 18918—2002《城镇污水处理厂污染物排放标准》一级B排放标准，且处理工艺单一、工艺流程不完善，再加上项目地处严寒地区，导致出水水质不稳定，亟需进行升级改造。基于该项目现状及存在的主要问题，对原有生化工艺进行升级，将A/O工艺改造为A2/O工艺，并增设“混凝沉淀+纤维转盘过滤”深度处理单元和消毒工艺。研究结果表明：改造后污水处理系统运行稳定、处理效果较好、出水水质可达到GB18918—2002《城镇污水处理厂污染物排放标准》一级A排放标准，该工程实践对寒冷地区污水处理厂升级改造有一定的借鉴意义。

关键词: 环境工程, 污水处理厂, 提标改造, A2/O工艺, 深度处理