The oxidation ditch process of the factory has main structures: the coarse grid before the pump,pumping station.fine grid ,aerated grit chamber ,oxidation ditch ,radial flow sedimentation tank.Sewage treatment structures the sludge thickening tank ,sludge dewatering room etc. During the preliminary design ,we must complete a specification, a general layout a map, an elevation map ;six maps of constructions used in process flow .The main task is to complete oxidation ditch plan and profile. The wastewatertreatment plant sewage treatment process:from the pumping station to Grit Chamber, enter oxidation ditch, secondary sedimentation tank, the final effluent; Sludge Process :the remaining sludge discharging from the secondary settling tankfirst to reach thickening tank, sludge thickening,and further dehydration, transported to the landfill.
After determining the sewage treatment process, to select the type of proper monomers structures.To design and calculate all the monomer structures ,including the determination of the design parameters、load、the size and the required materials、specifications etc.
According to the original data and the nature and composition of the wastewater ,selecting appropriate sludge treatment process to design and calculate all the monomer structures .
 Making the correct plane layout of the sewage、sludge treatment process for hydraulic calculation and elevation calculation.The structures need drawing are designed and calculated in detail including component ,the various parts of the Constitution and the specific size.
To design the sewage pumping station process of the sewage treatment process , determine the type,head,flow of the pump and calculate the pipeline system of the pump and water volume for the calculation of the pumping station plane size and the subsidiary structures.
According to the provisions of the cost of operation and management, to calculate the operation cose of sewage treatment unit and the main structures of the project cost budget.
Implementation of the national sewage effluent discharge standards (GB18918－2002）middle two standard.
The effluent quality: COD=99mg L-, BOD=29mg L-, SS=29mg L-, NH3-N=24mg L-,TN=19mg L-,TP=1.0mg L-.
Key words： craft of oxidation ditch; sewage treatment；calculation of constructions
目录
1绪论    1
  1.1 水体污染现状    1
1.2 国内外污水处理现状    2
    1.2.1 国内的污水处理现状    2
    1.2.2 国外的污水处理现状    2
  1.3 设计任务    3
  1.4 设计原则    3
  1.5 设计依据    3
2工艺流程的确定    4
  2.1 污水处理中生物方法的比较    4
    2.1.1 活性污泥法    4
    2.1.2 AB法    4
    2.1.3 SBR法    5
    2.1.4 氧化沟    5
    2.1.5 A/O法    6
  2.2 氧化沟的选择    7
    2.2.1 氧化沟的选择    7
    2.2.2 Orbal氧化沟的结构    8
  2.3 Orbal氧化沟的工艺流程    8
3 污水处理系统设计计算    9
3.1粗格栅    9
    3.1.1 主要设计参数    9
    3.1.2 工艺尺寸    10
    3.1.3水头损失    10
    3.1.4渣量计算    10
  3.2 提升泵房    10
    3.2.1 水泵选择    11
    3.2.2 集水池    11 氧化沟工艺某生活污水厂的设计(2):http://www.751com.cn/huaxue/lunwen_15594.html