摘要：本设计为某市污水处理厂的设计方案，总设计规模20万m3/d,设计出水水质执行《城镇污水处理厂污染物排放标准》GB18918-2002中的一级A标准。通过分析废水的水质、水量等特点，结合目前国内外生活污水处理的先进技术，本设计选择三级处理工艺，预处理选用曝气沉砂池和初沉池，沉淀废水中的泥沙等杂质；二级处理选用具有脱氮除磷作用的A2O工艺，即厌氧-缺氧-好氧生物脱氮除磷工艺。该工艺的优点是有效去除有机物、污泥产量少、运行费用低；三级深度处理选用高效沉淀池和气水反冲洗滤池，进一步降低废水中的有机物、悬浮物、氨氮等；废水最后经过消毒处理后，出水达标排放。

污水经过三级处理，污水中的污染物质得到有效去除，出水水质稳定，抗冲击负荷能力强，出水达到国家《城镇污水处理厂污染物排放标准》（GB18918-2002）中的一级A标准，适合城市污水处理厂的建设运行。

关键词：A2O工艺，气水反冲洗滤池，脱氮除磷

Abstract：The design of Sewage Treatment Plant in a City, the total design scale is 200,000 m3/d.Design water quality implements the Standard for Class A in GB18918-2002 for Pollutant

Discharge Standard for Urban Wastewater Treatment Plant. Pretreatment selection of aeration grit chamber and the initial settling tank, precipitation of waste water in the sediment and other impurities;Secondary treatment with a nitrogen and  phosphorus removal effect of the A2O process, namely anaerobic - anoxic - aerobic biological nitrogen and phosphorus removal process. The advantage of this process is the effective removal of organic matter, less sludge production, low operating costs;Three-level treatment of high efficiency sedimentation tank and gas-water backwash filter, to further reduce the waste water in the organic matter, suspended solids, ammonia and so on; Wastewater finally after disinfection, the water discharge standards.

Sewage after three levels of treatment, the sewage in the pollutants are effectively removed, water quality and stability, impact load capacity. Effluent to the national "urban sewage treatment plant pollutant discharge standards" (GB18918-2002) in the A standard. Suitable for urban sewage treatment plant construction and operation.

Keywords:A2O process,Gas water backwash filter,Nitrogen and phosphorus removal.

目 录

第一章绪论 1

1.1项目概况 1

1.2设计依据和标准 1

1.3进水水质水量及出水要求 1

1.4水质分析及工艺概述 2

1.4.1常规脱氮除磷污水处理工艺 2

1.4.2深度污水处理工艺 4

1.4.3污水处理流程比选 6

1.4.4污水处理流程确定 8

第二章污水处理工艺的设计计算 11

2.1中格栅 11

2.1.1设计说明 11

2.1.2格栅的设计计算 11

2.2提升泵房 15

2.2.1设计说明 15

2.2.2设计参数 15

2.2.3设计计算 15

2.3细格栅 17

2.3.1设计说明 17

2.3.2工艺设计简图