某12万吨日城市污水处理厂的A2O工艺设计

某12万吨/日城市污水处理厂的A2/O工艺设计

摘要

本次毕业设计的题目为某城市污水处理厂工艺的设计-A2/O工艺。主要任务是完成该污水处理厂的平面布置、各个构筑物的初步设计和一些处理构筑物施工图的设计。

初步设计要完成设计说明书一份、污水处理厂平面布置图一张、污水处理厂工艺流程图一张以及主要构筑物设计图三张；在主要构筑物设计图的设计中，主要是完成生物池、二沉池和接触消毒池的设计。

该污水处理厂工程，规模为12万吨/日。进水水质见下表：

污水进水水质单位：mg/L 项目COD cr BOD5NH4+-N SS TN0TP0含量270 135 30 135 30 3

本次设计所选择的A2/O工艺，具有良好的脱氮除磷功能。该污水厂的污水处理流程为：污水从粗格栅到污水提升泵房，再从泵房到细格栅，然后到旋流沉砂池，再进入生物池（即A2/O反应池），再从生物池进入二沉池，污水再经过接触消毒池后排入自然水体；污泥处理流程为：旋流沉砂池产生的垃圾直接外运处置，二沉池产生的剩余污泥则运入贮泥池，二沉池的回流污泥则通道管道、污泥回流泵房再次进入A2/O反应池，经过贮泥、加药处理后的污泥，进入污泥浓缩脱水车间，最后外运处理。污水处理厂处理后的出水水质要达到《城镇污水处理厂污染物排放标准》（GB 18918—2002）中的一级b标准。该标准的具体数据如下表所示：

出水水质标准单位：mg/L 项目COD cr BOD5NH4+-N SS TN0TP0含量60 20 15 20 15 1

关键词：A2/O工艺,脱氮除磷,污水处理,污泥处理

THE A2/O PROCESS DESIGN OF A CITY

SEWAGE TREATMENT PLATE

ABSTRACT

The subject of this graduation project for a municipal sewage treatment plant process design—A2/O process.Main task is to complete the layout of the sewage treatment plant,the preliminary design of the various structures and construction plans of dealing with the design of structures.

To complete the preliminary design of a design manual, wastewater treatment plant with a floor plan, flow chart of a sewage treatment plant and the design of three main structures;design of the main design of structures, mainly is the biological pool, secondary sedimentation tank design and contact disinfection tank.

This sewage treatment plant project,the scale is 120000m3/d. The influent water quality is in the table below.

Influent water quality units:mg/L Project COD cr BOD5NH4+-N SS TN0TP0 Content 270 135 30 135 30 3

The selected A2/O process, has a good Nitrogen and Phosphorus Removal.This sewage treatment plant for the sewage treatment process is: sewage from the coarse grid to enhance the pumping station,then from the pump to the fine grid,And then to the cyclone grit chamber, then entering the biological pool(A2/O reactor),then from the pool into the secondary sedimentation tank,after exposure to water disinfection and then discharged into the natural water ; Sludge treatment process is : vortex grit chamber sludge into the sludge

dewatering plant directly,secondary settling tank sludge are also brought into the workshop, secondary sedimentation tank produced returned sludge channel pipes, returned sludge from the pump to re-enter A2/O reactor, after treatment plant sludge dewatering sludge,mud into the storage pool, the last is outward processing. After the sewage treatment plant effluent quality to achieve "urban sewage treatment plant emission standards"(GB 18918-2002) in a first order and b standard.This standard's data is in the table below.

Effluent water quality units:mg/L Project COD cr BOD5NH4+-N SS TN0TP0 Content 60 20 15 20 15 1

KEY WORDS: A2/O process, Nitrogen and Phosphorus removal, Wastewater treatment, Sludge treatment