嘉兴联合污水处理厂提标改造工程设计及经验总结

嘉兴联合污水处理厂总规模为60×10^4 m^3/d,进水中工业废水比例约50%以上,污水厂分两期,一期工程(30×10^4 m^3/d)原采用初沉+氧化沟+二沉池的处理工艺,二期工程(30×10^4 m^3/d)原采用预曝气及初沉+水解酸化+AAO生反池+二沉池的处理工艺。本次提标将出水水质从《污水综合排放标准》(GB 8978-1996)的二级标准提高到《城镇污水处理厂污染物排放标准》(GB 18918-2002)的一级A标准。其中一期工程采用二级处理减量提标(新增二级处理部分采用了AAO和MBR两种工艺)并增加加砂高效沉淀池+滤布滤池+臭氧氧化的方案;二期工程采用在现有流程基础上增加加砂高效沉淀池+反硝化深床滤池+臭氧氧化的方案。本工程总投资为71915.67万元,提标后污水厂新增单位经营成本0.53元/m^3。本工程主体部分于2018年建成通水,一、二期出水水质均能稳定达到一级A标准的要求。

Design and Experience Summary of the Upgrading Project of Jiaxing United Wastewater Treatment Plant

The total treatment scale of Jiaxing united wastewater treatment plant was 600000 m^3/d.The proportion of industrial wastewater in influent water was more than 50%.The wastewater treatment plant was divided into two phases.The original treatment process of initial settling+oxidation ditch+secondary settling was used in the first phase 300000 m^3/d project,and the original treatment process of pre-aeration and initial settling+hydrolytic acidification+AAO+secondary settling was used in the second phase 300000 m3/d project.The effluent quality requirement has been raised from the second level of Integrated Wastewater Discharge Standard(GB 8978-1996)to the first level A standard of Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant(GB 18918-2002).The first phase project adopted the scheme of reducing the existing processing scale(AAO and MBR processes were used in the new secondary treatment section),adding sand-adding high-efficiency sedimentation tank&fiber rotary disc filter&ozone oxidation on the basis of the existing process.The second phase project adopted the scheme of adding sand-adding high-efficiency sedimentation tank&denitrification deep bed filter&ozone oxidation on the basis of the existing process.The total investment of the project was 719.1567 million yuan,and the operating cost increased by 0.53 yuan/m^3.The main part of the project had been completed in 2018,and the effluent of the first and second phases could meet the requirements of the first level A standard steadily.