摘要城市是人类生产生活的聚居地，自形成以来就面临着各种污染的治理问题。为保 护水环境，国家执行越来越严格的污染物排放标准。2002 年国家实行《城镇污水处 理厂污染物排放标准（GB18918-2002）》，对污水处理厂污染排放要求，尤其是对 氮磷的要求，较《污水综合排放标准（GB8978-1996）》有了很大的提高，新建城市 污水处理厂必须采用高效的污水脱氮除磷工艺。84549

城市污水采用集中处理方式，本城市污水处理厂设计是针对新区，采用雨污分流 制排水系统，将管网收集的生活污水、工业废水汇集到污水处理厂进行处理。一级处 理采用粗、细两道格栅和涡流沉砂池；二级处理核心构筑物为 4 座 UCT 池，对污水 具有较好的脱氮除磷效果；后续构筑物有二沉池和接触池。出水水质达到《城镇污水 处理厂污染物排放标准（GB18918-2002）》中的一级 A 标准。对于在处理过程中产 生的污泥进行压滤脱水，控制了污泥的二次污染。

毕业论文关键词：分流制排水系统，旋流沉砂池，UCT 工艺，脱氮除磷，污泥脱水

Abstract Since city became a settlement where human lived in, it has caused many kinds of pollution which has yet to be further management。 To protect water environment, our country has carried out a more strict standard for pollutants discharge。The Discharge Standard of Pollutants for Municipal Wastewater (GB18918-2002) was put into practice in 2002。It is much more strict compared to the Integrated Wastewater Discharge Standard (GB8978-1996),especially to the discharge of nitrogen and phosphorus。A more efficient wastewater denitrification and phosphorus removal process is needed for a new urban sewage treatment plant。

Centralized treatment is used for urban sewage。 Since the urban sewage treatment plant in this paper is designed in newly developed area, the rain sewage  persion system  is used for the collection of sewage and industrial waste water。 Primary treatment structures include coarse and fine screen, whirling grit clarifier。The core structures in the secondary treatment are four UCT pools。This wastewater treatment process has better effect on nitrogen and phosphorus removal。 Secondary settling tank and contact-oxidization tank are also used in this design。The effluent water quality index can meet Standard A of the first class in Discharge Standard of Pollutants for  Municipal  Wastewater (GB18918-2002) 。In order to control the secondary pollution of sludge,the pressure filtration technology has also been used to treat the sludge which formed in the process of biological treatment。

Keywords: separated drainage system; whirling grit clarifier; UCT process; nitrogen and phosphorus removal; dewatering of sewage sludge

目 录

第一章 绪论 1

1。1  我国城市污水处理的现状 1

1。2  城市污水处理的发展趋势 1

1。2。1 观念的转变 1

1。2。2 技术的支持 2

第二章 污水处理厂进水水质水量 4

2。1  设计进水水量 4

2。1。1 平均日污水量 Qp 的计算 4

2。1。2 设计最大流量 Qmax 的计算 4

2。2  设计进、出水水质 5

2。2。1 进水水质 5

2。2。2 出水水质 7

2。2。3 污染物去除率