农村混合生活污水排放特征及其处理工艺研究

Study on Discharge Characteristics and Treatment Process of Rural Mixed Domestic Sewage

针对农村生活污水污染问题已成为影响我国农村水环境的主要因素以及目前黑灰分离收集处理与现状不相符合,本文对崇明县某村的污水排放特征以及水量水质进行调研,并对硝化预处理系统结合人工湿地反硝化以及脱氮预处理结合人工湿地深度处理两种运行模式进行了深入探讨并分析了其去除机理,结果显示,硝化预处理系统结合人工湿地反硝化由于后续反硝化需要投加大量碳源从经济管理方面而言变得不可行;脱氮预处理结合人工湿地深度处理在预处理系统以进水3h、曝气2h、沉淀0.5h、排水0.5h、气水比40∶1的模式运行、人工湿地水力停留时间为48h条件下出水可满足《城镇污水处理厂污染物排放标准》(GB18918-2002)的二级要求,且因氨氮指标的降低大幅缩短了人工湿地的水力停留时间而减小占地面积。

Now the domestic sewage in rural area has become the main factor affecting the water environment, and the separated collection and treatment of black water and grey water do not coincide with the present situation. In this paper, the discharging flow rate and quality of domestic sewage in a village of Chongming county were investigated. The two operation modes of sewage？ purification, pre-treatment by nitrification combining denitrification using constructed wetland and pre-treatment by denitrifying combining advanced treatment using constructed wetland were discussed and their mechanisms were discussed. The results showed that the former was unfeasible economically due to requirement of a lot of carbon sources. While for the latter, the effluent quality met the requirement of Class lI from the Pollutants Discharge Standard of Municipal Sewage Treatment Plant （ GB18918-2002） of China at the operation conditions of pre-treatment influent for three hours, aeration for two hours, sediment for 0. 5 hour, drainage for 0. 5 hour, gas to water ratio 40：1 and 48 hours of hydraulic retention time for constructed wetland. Furthermore, the reduced ammonia nitrogen greatly shortened the hydraulic retention time of the constructed wedand, sequentially reduced the land occupation.