通过细菌数量评价污水处理工艺及其对纳污水体的影响

城市污水的再生回用已经成为解决城市水资源不足问题的一个重要途径,再生水在城市生产、生活中发挥重要作用的同时,也引起人们对再生水对环境和公众的影响及安全问题的关注。污水厂对污水中微生物的去除效率直接影响到再生水的微生物安全性。通过检测污水处理厂不同季节各工艺段及纳污水体中细菌数量,进行了不同工艺的细菌去除效率及对纳污水体的影响评价。结果表明,二级处理出水的细菌去除率可以达到1.67 log10,对河流的还清起到了一定的积极作用。沙滤与絮凝沉淀工艺处理出水的细菌去除率达到2 log10,但在用于喷洒、景观回用方面有必要消毒以保证不对公众健康有负面影响。

Assessment Effluent Treatment Craft and Impact of Effluent Discharge on Regional Water Environment by Bacteria Quantities

The recycle of post-treatment sewage is an important method proven to solve the problem of shortage for urban water resources.With increasing quantity of wastewater reuse,the potential risks caused by reclaimed water are concerned.The effectiveness of wastewater reclamation facilities to bacteria control directly influences public health risks.In this study,we have detected the bacteria quantity at different stages of treatment at a full-scale water reclamation facility and regional water environment to assess the effectiveness of bacteria removal and impact of regional water environment in different seasons.The results showed that bacteria number was reduced by 1.67 log10 in secondary effluent.The stage was selected,due to the fact that the secondary effluent plays a good role in cleaning the regional wastewater.Furthermore,sand filtration and chemical coagulation-flocculation treatment utilized at the plant could reduce bacteria number by 2 log10.If reclaimed water is expectedly used in domestic,an additional disinfection maybe required so that it will not be harmful to public health.