In the design: the grid closure was set up to bite off larger solids and floats; catch pit was used for collecting water and drainage；pool could distribute the sewage to triple oxidation ditch reasonably；Sinking sand pool with rotational flow used hydraulic vortex to separate the sediment and organic matter apart and accelerate sand sedimentation, in order to achieve the sand removing objective. Rotational flow grit chamber is the use of hydraulic vortex, the sediment and organic matter apart, accelerated sand sedimentation, in order to achieve the sand removing objective. The three groove-type oxidation ditch was mainly used for nitrogen removal and also could degrade organic matter; sludge thickening tank's main function was to decrease the residual moisture content of sludge and reduce the volume of sludge to facilitate the follow-up.
In accordance with the established process, the design calculated the main dimensions, the hydraulic losses and pipeline of structures (including the grating, grit chamber dole, sinking sand pool with rotational flow, three groove-type oxidation ditch, etc.) and finished the instruction of the design process , Process Flow Diagram (including high-level-floor layout), factory floor layout and the map of main monomer structure.
The process of the three groove-type oxidation ditch was simple，eliminated the primary sedimentation tank and sludge digestion system, saved capital construction investment and operation cost. At the same time, it owned aeration equipment and structural persity, flexible operation, convenient management, and ensured the effluent to reach the wastewater discharge standard, realized the rational utilization of water resources。
This design has feasible technology, rational cost. The investment of the project is RMB55,425,000, operating costs RMB7,332,000/ year, equivalent to cost RMB 0.51 for 1 m3 sewage treatment。
The treated wastewater is expected to achieve "urban sewage treatment plant emission standards for pollutants" (GB18918-2002), emission standards at the national
level B, that is: CODcr ≤ 60mg / l, BOD5 ≤ 20 mg / l, pH = 6 - 9, SS ≤ 20mg / l, ammonia nitrogen ≤ 8mg / l. After being treated by three groove-type oxidation ditch, 3723 ton CODcr can be reduced, and the contaminated water will be greatly improved to achieve the elimination of pollution, protection of the environment, the purpose of continual developing.
Key words: City life sewage; three groove-type oxidation ditch; CODcr
目录
目录 1
1 绪论 2
1.1 项目背景 2
1.1.1 工程服务区概况 2
1.1.2 工程建设的必要性 3
1.2 设计依据、原则与范围 4
1.2.1 原则 4
1.2.2 依据 4
1.2.3 范围 4
1.3 设计规模和目标 4
1.3.1 服务区人口基本情况 4
1.3.3 进出水水质 5
2 污水处理工艺的选择 5
2.1 主体工艺的选择与比较 5
2.1.1 A2/O法 5
2.1.2 CASS工艺 6
2.1.3 氧化沟工艺 8
2.1.4 各工艺的比较 9
2.1.5 氧化沟的选择 10
2.2 沉砂池的比较与选择 11
2.2.1 平流式沉砂池 11
2.2.2 曝气沉砂池 11
2.2.3 旋流式沉砂池 12
2.2.4 沉砂池的选择 12
2.3 消毒设备的比较与选择 12
2.3.1 液氯消毒 12
2.3.2 臭氧消毒 13
2.3.3 紫外消毒 13
2.3.4 消毒设备的选择 14
2.4 污泥处置工艺的比较与选择 15 4万吨日生活污水处理工艺设计+CAD图纸(2):http://www.751com.cn/huaxue/lunwen_2052.html