摘 要

本次毕业设计的题目为湖北省大冶市北部地区排水工程设计。主要任务是完成湖北省大冶市北部地区排水工程设计，包括污水管网工程、雨水管网工程与污水处理厂工程。

大冶，位于湖北省东南部，长江中下游南岸。大冶市地处幕阜山脉北侧的边缘丘陵地带，地形分布为南山北丘东西湖，南低北高东西平，海拔高度为120—200米，最高点海拔839.9米，最低点海拔11米，工程地质良好。长江流经市东北隅，市内主要河流有17条，湖泊有大冶湖、保安湖和三山湖。

大冶属亚热带大陆性季风气候，夏季主导风向东南风。年平均气温16.9°C，极端最高气温40.1°C，极端最低气温-10°C，年均无霜期261天，年均降水量为1385.8毫米。

受纳水体大冶湖位于设计区域南部，由东向西流经设计区域，常水位16 m，五十年一遇洪水位19.57 m。

排水管网采用完全分流制系统，污水自东向西流，采用一根由东向西的主干管，排入位于大冶市北部地区西南方向的污水厂进行污水处理，经深度处理后污水排入大冶湖。雨水根据就近排放的原则，将整个市区分为五个部分，设置独立的雨水排出系统，在雨水管线末端设置截留井，将初期雨水截留到污水处理厂雨水调蓄池中，按10%经污水厂处理后排入大冶湖，未截留雨水直接排入大冶湖。

根据河流流向和城区坡度，污水处理厂定址于大冶市北部地区的西南方向，近期处理规模约为1.58万m³/d，通过污水厂工程投资综合指标，计算污水厂近期工程投资。远期投资以近期处理构筑物为2组计，远期每增加一组，附加5%的工程投资，本设计近期2组，远期3组，计算得出的近远期投资金额后，可以得出总投资预算。管网费用为排水管材费用，人工费以及管理费用等，排水成本的估算采用“要素成本估算法”，成本要素包括年折旧费，大修理基金，电费，药剂费，工资福利费，维护费，管理费及单位制水成本、运行费用。根据处理水特点和受纳水体水质要求，采用一级A处理要求。因为污水处理厂设计流量较小，核心生物处理工艺选择SBR工艺，主要工艺流程为进水→中格栅→进水泵房→细格栅→SBR池→深度处理提升泵房→高密度澄清池→消毒池→巴氏计量槽→出水。

根据所提供的原始资料，我在本设计中完成了大冶市北部地区排水管道系统、污水处理厂的设计计算，绘制图纸8张（A1），完成设计说明书和设计计算书各一份。

关键词：湖北省大冶市北部地区排水工程、分流制排水系统、SBR工艺、初期雨水处理

Abstract

The title of this graduation project is drainage engineering design in the north part of Daye City, Hubei Province. The main task is to complete the drainage engineering design of the north of Daye City, Hubei Province, including sewage pipe network project, Rain Water pipe network project and sewage treatment plant project.

Daye City is located in the southeast of Hubei Province, on the South Bank of the middle and lower reaches of the Changjiang River. Daye City is located in the edge hilly area on the north side of Mufu mountain. The terrain is distributed in the East-West lake of the South Mountain and the north. The south is low, the north is high, the East-West is flat, the altitude is 120-200m, the highest point is 839.9m, and the lowest point is 11m. The engineering geology is good. The Yangtze River flows through the northeast corner of the city. There are 17 main rivers in the city, including Daye lake, Baoan lake and Sanshan lake.

The climate belongs to the subtropical continental monsoon climate. The southeast wind is dominant in summer. The annual average temperature is 16.9 ° C, the extreme maximum temperature is 40.1 ° C, the extreme minimum temperature is - 10 ° C, the annual frost free period is 261 days, and the annual average precipitation is 1385.8 mm.

The Daye Lake, the receiving water body, is located in the south of the design area and flows through the design area from east to west with a constant water level of 16 m and a 50 year flood level of 19.57 m.

The drainage pipe network adopts the complete diversion system, and the sewage flows from east to west. A main pipe from east to west is used to discharge the sewage into the sewerage treatment plant located in the southwest of the north area of Daye City for sewage treatment. After the advanced treatment, the sewage is discharged into the Daye Lake. According to the principle of nearby discharge, the whole urban area is divided into five parts. An independent Rain Water drainage system is set up. A interception well is set at the end of the rainwater pipeline to intercept the initial rainwater into the rainwater regulation and storage pool of the sewage treatment plant. The rainwater is discharged into Daye Lake after being treated by the sewage plant at 10%, and the rainwater without interception is directly discharged into Daye lake.

According to the flow direction of the river and the slope of the urban area, the sewage treatment plant is located in the southwest of the north area of Daye City. with a recent treatment scale of about 15800 m³ / day. the recent project investment of the sewage treatment plant is calculated by the comprehensive index of the project investment of the sewage treatment plant. The long-term investment is calculated by taking the short-term treatment structure as two groups. For each group increased in the long-term, 5% of the project investment will be added. In this design, two groups of short-term investment and three groups of long-term investment can be calculated and the total investment budget can be obtained. The pipe network expenses are the drainage pipe expenses, labor expenses and management expenses. The drainage cost is estimated by the "factor cost estimation method". The cost elements include annual depreciation expenses, overhaul fund, electricity expenses, pharmaceutical expenses, wages and welfare expenses, maintenance expenses, management expenses, unit water cost and operation expenses. According to the characteristics of treated water and the quality requirements of receiving water, the first level a treatment requirements are adopted. Because the design flow of the sewage treatment plant is small, the SBR process is selected as the core biological treatment process. The main process flow is water inlet → medium grid → water inlet pump room → fine grid → SBR tank → advanced treatment lifting pump room → high-density clarifier → disinfection tank → pasteurization tank → water outlet.

According to the original data provided, I completed the design and calculation of the drainage pipeline system and sewage treatment plant in the north area of Daye City, and drew 8 drawings (A1, including an ink map and a pencil drawing). Complete one copy of the design specification and one copy of the design calculation document.

Key words: Drainage project in the north area of Daye City, Hubei Province, Shunt drainage system, SBR process, Initial Rain Water treatment.

目录

第一章 绪论 1

1.1 研究背景 1