多段多级AO工艺用于全地下式陡沟河污水处理厂二厂

Application of Multi-stage AO Process in Dougouhe No.2 Underground Wastewater Treatment Plant

陡沟河污水处理厂二厂项目设计规模为10.0×10^(4)m^(3)/d,是目前四川省已建成并投产运行的最大的全地下式污水处理厂。采用“多段多级AO生化池/矩形周进周出二沉池/反硝化滤池/加砂高效沉淀池”三级污水处理工艺。运行结果表明,出水水质达到了《四川省岷江、沱江流域水污染物排放标准》(DB 51/2311—2016)。该工程具有箱体集成化、出水标准高、工艺高效等技术特点。设有厂内外中水回用系统,并应用了精确曝气控制系统、污水源热泵中央空调系统等绿色节能技术;采用“补偿收缩混凝土/膨胀加强带/加强池体水平配筋”技术解决混凝土早期的温度和收缩应力问题;采用集散型自动化控制方式提高污水厂运行的可靠性。

The design scale of Dougouhe No.2 wastewater treatment plant is 10.0×10^(4)m^(3)/d, which is the largest underground wastewater treatment plant that has been built and put into operation in Sichuan Province. The three-stage wastewater treatment process consists of multi-stage AO biochemical tank, rectangular round-in and round-out secondary clarifier, denitrifying filter and high-efficiency sand sedimentation tank. The operation results showed that the effluent quality reached the limit specified in Discharge Standard of Water Pollutants in Minjiang River and Tuojiang River Basin in Sichuan Province(DB 51/2311-2016). The project has the technical characteristics such as integration of structures,stringent standards of effluent quality and high efficiency of the treatment process. The plant has internal and external reclaimed water reuse system, and green energy-saving technologies such as accurate aeration control system and sewage source heat pump central air conditioning system. The technologies of shrinkage-compensating concrete, expansion strengthening band and strengthening horizontal reinforcement of the structure were adopted to solve the temperature and shrinkage stress of concrete in early stage, and the distributed automatic control method was applied to improve the reliability of wastewater treatment plant operation.