摘 要

当今，随着经济的快速发展，人民生活水平的不断提高，环境污染日趋严重，加大城市生活污水治理力度势在必行。本次设计的是湖北省长阳某镇排水工程初步设计，最大设计水量为70000m³/d。设计出水水质执行《城镇污水处理厂污染物排放标准》GB18918-2002一级A标准。本设计主要包括两大部分：第一部分：排水管网初步设计。该地区采用分流制排水系统，即雨水和污水通过两个系统排除，最后，污水汇入城市污水处理厂进行集中处理，污水管道为了满足最小流速的要求，对于管道有最小坡度的规定，由于该城市地形平坦，埋深降落很快，所以污水主干管布置在排水区域的中间位置，以兼顾干管的埋置。第二部分：污水处理厂的设计。通过查阅资料以及工艺对比，采用改良的卡鲁塞尔（Carrousel）氧化沟工艺。Carrousel氧化沟使用定向控制的曝气和搅动装置，向混合液传递水平速度，从而使被搅动的混合液在氧化沟闭合渠道内循环流动。因此该氧化沟具有特殊的水力学流态，既有完全混合式反应器的特点，又有推流式反应器的特点，沟内存在明显的溶解氧浓度梯度。本污水处理厂流程为：污水首先通过粗格栅去除较大的漂浮物，然后经提升泵提升后流经细格栅去除较小的漂浮物和悬浮，经过旋流入沉砂池去除一部分BOD和砂砾，接着与回流污泥一同流入卡鲁塞尔氧化沟进行生物降解，并在氧化沟内发生厌氧→缺氧→好氧反应，使污水中的污染物切底被降解，然后由二沉池发生泥水分离，最后经过紫外消毒达标排放。根据工艺进行各个构筑物的的设计计算，以及高程和平面布置，绘制平面布置图、高程布置图和各个构筑物的平面剖面图，污水经处理后出水水质达到《城镇污水处理厂污染物排放标准》（GB18918-2002）一级A标准，污泥经过二沉池一部分污泥回流至厌氧区，剩余污泥回流至集泥井，最后污泥处理采用带式浓缩脱水一体机的处理工艺，采用污泥填埋作为近期污泥的处置方案。通过脱水后外运。本设计概述了改污水处理厂的设计计算以及经济预算等。

关键词：污水处理；氧化沟；工艺流程；污染物

Abstract

Nowadays, with the rapid economic development and the people's living standard improved, environmental pollution is more serious. So it is both inevitable and necessary to develop the urban sewage treatment. This design is a preliminary design of a drainage project in a town in Changyang, Hubei Province, with the largest design capacity of 70000m3/d.The effluent quality carries out A-level standards from pollutant emission standards of urban sewage treatment plant—GB18918-2002.The report is consists of two parts.Part One:The primary design of the municipal wastewater system .There are two kinds of municipal wastewater,the sanitary sewers and the storm sewers.They are collected in two separate systems.In the end, the sanitary sewers transfer into the municipal wastewater treatment plant and the storm sewers flow into the river.Collecting and intercepting sewers must be placed at a sufficient grade to allow for adequate velocity during low flows,but not so great as to promote excessively high velocities when the flows are at their maximum .Because of the land is very large and plain,the depth of the drain descends rapidly. So sewage trunk pipes arranged in the middle of the drainage area, in order to take into account the dry pipe buried.Part Two:Design of wastewater treatment plant. An improved Carrousel oxidation ditch process was developed by comparing data and technology. The Carrousel oxidation ditch uses the directional controlled aeration and agitation device to transfer the horizontal velocity to the mixture, so that the mixed liquid is circulated in the closed channel of the oxidation ditch. Therefore, the oxidation ditch has special hydrodynamic flow, not only the characteristics of the complete mixed reactor, but also the characteristics of the push flow reactor. There are obvious concentration gradient of dissolved oxygen in the ditch. The sewage treatment plant process is as follows: the sewage is first removed by the coarse grille and the larger floating material is removed, then the lifting pump is lifted to the fine grille to remove the smaller floating objects and suspending, and a part of the BOD and gravel is removed through the Swirling Sediment Pool, and then the sludge flows into the Kalu Searl oxidation ditch together with the reflux sludge to be biodegraded. The anaerobic, anoxic and aerobic reaction occurred in the oxidation ditch, and the bottom of the pollutants in the sewage was degraded, and then the mud water was separated by the two sink. Finally, [2] was discharged by UV disinfection. According to the process of the design and calculation of the various structures, as well as elevation and layout, drawing plane layout, elevation layout and the plane profile of each structure, the effluent water quality reaches the first grade A standard of the pollutant discharge standard of urban sewage treatment plant (GB18918-2002), and the sludge passes through two sinks. A part of the sludge is reflued into the anaerobic area, and the remaining sludge is reflued to the mud well. Finally, the sludge treatment process is adopted by the belt concentrating and dewatering machine, and the sludge landfill is used as the disposal scheme of the sludge in the near future. Carry out after dehydration. This design outlines the design and calculation of the sewage treatment plant and the economic budget.

Keywords: sewage treatment; oxidation ditch; process flow; pollutants

目录

摘 要 1

Abstract I

第一章 绪论 1

1.1 项目介绍 1

1.2 设计原始资料 1

1.2.1 设计水量 1

1.2.2 设计进出水水质 2

1.3 设计要求、依据及原则 2

1.3.1 设计要求 2

1.3.2 设计依据 2

1.3.3设计原则 3

第二章 设计说明 4

2.1 设计情况概述 4

2.1.1 城市概况 4

2.1.2 给排水工程现状 4

2.1.3 设计依据 5

2.2 城市管网系统规划设计 6

2.2.1污水管网规划总则 6

2.2.2污水系统体制比较与确定 6

2.2.3工业废水的处理与排放 7

2.2.4 污水厂厂址的选择 7

2.2.5 污水管网的布置 7

2.2.6 方案比较 7

2.2.7 污水管道设计 9

2.2.8 雨水管道布置 12

2.2.9 雨水管道材质确定 13

2.3 常用污水处理工艺 13

2.3.1 A2/O工艺 14

2.3.2 氧化沟工艺 14

2.3.3 SBR工艺 15

2.4 工艺流程确定 15

2.4.1 工艺比较 15

2.4.2 工艺流程 16

2.4.3 工艺流程介绍说明 17

第三章 设计计算 19

3.1 污水管网计算 19

3.1.1 污水管网流量计算 19

3.1.2 污水管网水力计算 20

3.2 雨水管网计算 20

3.2.1 雨水管网流量计算 20

3.2.2 雨水管网水力计算 21

3.3 粗格栅 21

3.4 提升泵房 23

3.4.1 提升泵 23

3.4.2 集水池 24

3.5 细格栅 24

3.6 沉砂池 28

3.6.1相关要求 28

3.6.2 设计计算 29

3.7 卡鲁赛尔氧化沟 31

3.7.1 设计说明 31

3.7.2 设计计算 32

3.8 配水井 40

3.8.1 配水井设计说明 40

3.8.2 配水井设计计算 41

3.9 二沉池 42

3.9.1 二沉池说明 42

3.9.2 二沉池计算 43

3.10消毒渠 47

3.10.1 消毒渠设计说明 47

3.10.2 设计计算 47

3.11 污泥处理 48

3.11.1 浓缩脱水 48

3.11.2污泥脱水间 49

3.11.3污泥回流泵房 49

3.12 平面布置 50