设计总说明：本设计所涉及的污水处置厂位于上海市西南部，其废水主要是来自该地区的生活污水，污水量三期3万m3/d，CODcr：400mg/L、SS:300mg/L
，NH3-N：25mg/L、BOD5：200mg/L。
经过对各生物法处置工艺的研究比较，确定采用T型氧化沟工艺，用以达到脱氮除磷、降解有机物的目的，而且到达要求处置后达到《城镇污水处置厂污染物排放标准》（GB18918-2002）一级标准的B标准。20430
策划中，通过格栅截流较大的漂浮物或悬浮物;曝气沉砂池是使泥沙与有机物分开，加速砂粒的沉淀，以达到除砂目的；配水井设置在氧化沟之前，目的是将原水分配到氧化沟；氧化沟的重要作用是实用沟内的表曝产生的径流为动力，推进氧化沟内液体流动，从而有效地降解废水中有机污染物，同时达到脱氮的目标。
根据确定的工艺流程，本设计通过对构筑物(包括格栅、曝气沉砂池、T氧化沟、配水井与污泥浓缩池)主要尺寸的设计计算、水力损失及管路计算，完成了设计工艺说明、工艺流程图（含高层布置）、厂区平面布置图与主体构筑物单体图。
在规划中废水经水泵一次提升后，靠重力流完成污水的全工艺处置，避免污水的反复提升，以节约能源损耗，减较少废水处置用度，有利于操作管理。
本设计具有技术上可行、经济上合理的效果。由于T型氧化沟工艺池深较浅，而且不设初沉池，因此土建费用较少，另外该工艺运行管理简单，自动化程度高，也降低了运行管理的费用，所以整个工艺流程具有总投资较少，运行稳定、二次污染较少、处置效果好、能耗较少等优点，并确保废水处置达标排放。本工程投资费用为2223万元，折合污水处置费用0.41元/ 。
废水经处置后，估计可以达到《城镇污水处置厂污染物排放标准》（GB18918-2002）中的国家一级排放标准，即：CODcr≤60mg/ L，SS≤20mg/ L， ≤8mg/ L，BOD5≤20mg/ L，TN≤20mg/L，每年削减向环境排放的COD为1752吨，从而使受污染的水质得到极大的改善，达到消除污染、实现保护环境、造福人类的目的。
毕业论文关键词： 废水处置；T型氧化沟；活性污泥法；
 A sewage treatment plant design of T-oxidation ditch
General Information Of Design：The design involved a sewage treatment plant is located in west-south of ShangHai Province, its water mainly comes from domestic sewage in the region . The initial design plans: The amount of sewage is 30000 m3 / d (the third period process). The indicator of waste water quality standard is: CODcr: 400 mg/L, BOD5: 200 mg/L, NH3-N: 25 mg/L,  SS: 300 mg/L.
By comparing the research of several biology treating processes, the design uses the T type oxidation ditch to remove the nitrogen and TP,and the water which are treated should meet the standards of urban sewage treatment plant emission standards（GB18918-2002）, emission standards at the B level.
Design, through the closure of a large grid suspended solids or floating debris; Aerated grit chamber is to use water to separate the silt and organic matter to speed up the sand in the sediment to achieve grit aimes;distribution well is placed in the front of oxidation ditch to distribute the original water to different oxidation ditch ; oxidation ditch main role is to use the table exposed trench runoff generated as a driving force to promote the oxidation of liquid groove flow, thus effectively Degradation of organic pollutants,  phosphorus removal at the same time to achieve the purpose;
  To keep accordance with the established process, the design selects the process parameters of structures (including the grating, Aerated grit chamber,T type oxidation ditch, distribution well and sludge thickening tank) and calculates the main size, the hydraulic loss, and finished of Introduction of Design Process, Process Flow Diagram, Factory Layout and Main Monomer Structure Map. 某污水处置厂T型氧化沟工艺设计+CAD图纸:http://www.751com.cn/huaxue/lunwen_12204.html