城市污水处理特点 摘要： 城市污水主要包括生活污水和工业污水，由城市排水管网汇集并输送到污水处理场进行处理，城市污水不同于工业污水,是人类生活中产生的污水，是水体的主要染污源之一，主要是排泄物和洗涤污水。

城市污水处理工艺一般根据城市污水的利用或排放去向并考虑水体的自然净化能力，确定污水的处理程度及相应的处理工艺。

目前城市污水处理工艺大都采用一级处理和二级处理，一级处理采用物理方法,主要通过格栅拦截、沉淀等手段去除废水中大块悬浮物和砂粒等物质,这一工艺已很成熟，差别不大。

二级处理常用生物法和絮凝法，絮凝法主要是除去一级处理后废水中无机的悬浮物和胶体颗粒物或低浓度的有机物。

生物法是除去一级处理后废水中的有机物,主要通过微生物的生命运动等手段来去除废水中的悬浮性、溶解性有机物以及氮、磷等营养盐。

目前这一处理工艺有多种方法，即CCAS、SBR，A/O、A2/O、传统活性污泥及氧化沟，生物滤池等工艺。

关键词： 城市污水 一级处理 二级处理 活性污泥法 生物膜 Abstract: Urban sewage mainly includes domestic sewage and industrial sewage, which are collected and transported by the urban drainage pipe network to the sewage treatment plant for treatment. Urban sewage is different from industrial sewage, which is generated in human life. It is one of the main sources of water pollution, mainly including excreta and washing sewage. Generally, according to the utilization or discharge direction of urban sewage and considering the natural purification capacity of water body, the treatment degree of sewage and corresponding treatment process are determined. At present, most of the municipal sewage treatment processes adopt primary treatment and secondary treatment, and primary treatment adopts physical methods, mainly through grille interception, precipitation and other means to remove the bulk suspended matter and sand particles in the wastewater, and this process has been very mature, with little difference. In secondary treatment, biological method and flocculation method are commonly used. Flocculation method is mainly used to remove inorganic suspended matter, colloidal particles or low-concentration organic matter in the wastewater after primary treatment. Biological method is to remove the organic matter in the wastewater after the first treatment, mainly through the microbial life movement and other means to remove suspended, dissolved organic matter and nitrogen, phosphorus and other nutrients in the wastewater. At present, there are many methods for this treatment process, namely CCAS. SBR, A/O, A2/O, traditional activated sludge and oxidation ditch, biological filter and other processes. 1. 当前城市污水处理现状 （1）城市污水回用率较低。

污水处理的目的很大程度就是要重新的利用,欧美等发达国家的污水回用率相对较高，但目前我国的城市污水处理后的回收率仅为6.2%,我们应该在提高城市污水处理技术的基础上,提高城市污水回收率,缓解当前水资源紧缺的问题。

（2）污泥.臭气控制不力。

当前我国大多数地区的污水处理方式还是以活性泥法为主,这种方式的优势就是成本便宜,设备相对简单,但是其污水处理速度较慢,并且对污水处理不彻底，因此常会出现处理后的水出现水体发臭的状况，并且采用活性污泥处理后的污泥通常采用填埋的方式进行处理,这种方式对掩埋处的环境也会造成极大的影响。