四川省达州市宣汉县排水工程设计设计总说明(给水排水工程毕设)

设计总说明

宣汉县的总人口为13.5万，城区的总面积为416.99公顷。本设计为四川省达州市宣汉县排水工程的初步设计设计，主要任务为污水管网初步设计、雨水管网初步设计、污水处理厂的初步设计。

污水管网和雨水管网设计的主要任务是对城区进行排水区域的划分，管网定线，确定管径和坡度，管网定线时要求结合地形让水量利用重力排出。在此设计总所有的管材选用钢筋混凝土管，以节约造价。考虑到夏季暴雨集中，对于水管要求较高，所以雨水管管径选取时要求偏大一些。

污水处理厂设计污水流量为3.8万m3/d，设计的主要任务是完成污水及污泥处理方法选择、工艺设计计算、污水平面图、高程图及单项处理构筑物施工图设计。本设计的污水主要来源为生活污水和工业废水，主要污染质是BOD、COD、SS、TN、TP，结合出水水质（《城镇污水处理厂污染物排放标准》GB18918—2002中的一级B标准）、气象条件、人口分布等条件，并考虑到要进行脱氮除磷，确定污水处理的方法为卡鲁塞尔氧化沟工艺，污水经过处理之后就近排入水体；污泥处理采用重力浓缩池，污泥处理之后泥饼运至果园做肥料。

此次设计的成果有两种展现方式，一是设计说明书，二是设计图纸。设计说明书主要是设计的管网和构筑物计算的过程，而图纸则是将这些计算结果反映出来，让大家可以更加直观的看到设计的结果。本次设计成果设计说明书一共70页，图纸一共20张。

通过此设计，本县的水污染问题会得到较好的解决，产生良好的环境效益，同时也会产生很好的经济效益和社会效益。

Specification

The total population of Xuanhan County was one hunderd and thirty-five thousand.The total area of the city of four hundred and sixteen point ninety-nine hectares.The total area of the city is 416.99 hectares.This is the preliminary design of drainage works of Xuanhan County,Dazhou city in Sichuang Province.The main task of the project are preliminary design of sewage pipe network,preliminary design of rainwater pipe network and preliminary design of sewage treatment.

The main task of sewage and rainwater pipe network is to division of drainage area,ensure the pipe line,determine the diameter and slope.The pipe line should follow the terrain so the water can be discharged by gravity when we design the pipe network.In the design of the total of all the selection of pipeline choose steel reinforced concrete pipe to savecost.Considering the heavy summer rains,The sudden increase of water demand is higher than usually,so the selection of rain water pipe diameter requires large number.

The sewage flow this sewage treatment plant is three hundred and eighty thousand cubic meters per day.The main task of sewage treatment plant is to complete the scheme selection of sewage and sludge treatment design computation and design the sewage plant horizontal plan elevation map and construction drawing of the structure.The major source of the sewage including domestic sewage and industrial waste water that the main pollutants are BOD,COD,SS,TN,TP.Combining the outflow quality(The B standard in\sewage treatment plant pollutant discharge standard\- 2002),population distribution,meteorolohgic condition and others.Also considering to get rid of the nitrogen and the phosphor byactiviated sludge at the same time.There for carrousel oxidation ditch was used in the design.The effluent is discharged into the nearest river.The mud is sended to gravity thickener first to reduce a part of water,and then the treated sludge is used for fertilizer of the orchard after mechanical dewatering.

The design result share two way,one is the design specification,the other is the designdrawings.The design specificationis mainly a process of design and calculation of network, structures,and the drawing show the results reflected,so that we can be more intuitive to see the results of the design.The design results.including specification total of 70 pages ,drawings total of 20 pieces.

Water pollution problem of this county can be solved according to this design.It has very good enviornmental benefits econmic and social benefits.