摘要:目前我国共有17000个建制镇，绝大多数没有排水和污水处理设施，而且，由于二十几年来，乡镇企业的蓬勃发展，造成一些中小城镇尤其是经济比较发达的中小城镇，污染严重，已经影响到人民的生活和健康。城市生活污水排放已是我国城市水的主要污染源，城市生活污水处理是当前和今后城市节水和城市水环境保护工作的重中之重，这就要求我们要把处理生活污水设施的建设作为城市基础设施的重要内容来抓，而且是急不可待的事情 。污水处理是为使污水达到排水某一水体或再次使用的水质要求，并对其进行净化的过程。

　　　本文介绍了国内外多种污水处理工艺以及城镇污水处理的设计内容，其处理工艺采用的是推流曝气池工艺，并对流程中的主要构筑物进行详细的参数计算。

　　　推流曝气池是水流流动形式为推流式的曝气池。真正有回流的推流系统污水处理效果较好，但由于水流过程中纵向扩散现象存在，但难得到真正的推流状态。缺点是耐冲负荷较差。活性污泥生物处理过程中的传统活性污泥法、阶段曝气法、生物吸附法等方法中均为推流式曝气池。

关键词：推流曝气池，污水处理，环境保护

Abstract:There are currently 17000towns, the vast majority there is no drainage and sewage treatment facilities, and, because twenty years, the rapid development of township enterprises, resulting in some small towns, especially small and medium towns with more developed economy, pollution is serious, has affected To people's lives and health. Municipal sewage is the main source of urban water, urban sewage treatment is the current and future urban water conservation and urban water environmental protection a top priority, which requires us to make the construction of domestic wastewater treatment facilities as an important urban infrastructure part of the task, and is impatient to do. Sewage treatment is to drain the sewage water or re-use of a water quality requirements, and its process of purification. 

　　　This article describes a variety of wastewater treatment process at home and abroad as well as the design content of urban wastewater treatment, the treatment process uses a plug-flow aeration tank technology, the main structures and process parameters detailed calculations. 

　　　Plug-flow aeration tank is the water flow in the form of plug-flow aeration tanks. Realreturn of the plug-flow wastewater treatment system is better, but because the process of vertical diffusion currents exist, but hard to really push the current state. The disadvantage is less resistant to impulse loads. Activated sludge biological treatmentprocess in the conventional activated sludge, aeration stage, biological assay and other methods are plug-flow aeration tank.

Keyword：Plug-flow Aeration Tank，Sewage Treatment，Environment Protection