城市污水系统水量平衡分析

Analysis of Water Volume Balance in Urban Sewage Systems

摘要:

城市污水系统的水量平衡分析是保障城市水环境安全的核心环节，涉及原生污水量、设施运行量、地下水渗入量和雨水进入量这4类关键水量的动态交互。以“厂、站、网、户”4个方面为研究对象，分析上海市中心城区3条典型支线污水系统上述4类水量的组成量，结果表明：1号、2号、3号支线2022年的地下水渗入率分别为20.5%、14.1%和7.5%，2023年的地下水渗入率分别为16.1%、14.5%和25.9%。雨污混接改造措施可使地下水渗入量得到一定程度的整治，但管网长期处于高水位运行，且地下水位较高，如降低污水管道运行水位，地下水渗入率可能会升高；1号、2号、3号支线2022年雨水进入比例分别为0.4%、0%和6.9%，2023年雨水进入比例分别为0%、10.6%和10.2%，随着初期雨水治理力度的加大，分流制系统的雨水进入量有所增加。

Abstract:

The analysis of water volume balance in urban sewage systems is a central part in ensuring the safety of urban water environments, encompassing the dynamic interaction among four key water volumes, such as raw sewage, facility discharge, groundwater infiltration and rainwater infiltration. Taking four aspects of "WWTPs, pumping stations, sewer networks and households" as the research objects, the composition of these four water volumes in three typical branch sewage systems in the central urban area of Shanghai is analyzed. The result shows that in 2022, the groundwater infiltration rates of Branch 1, Branch 2 and Branch 3 were 20.5%, 14.1% and 7.5%, respectively, and in 2023, were 16.1%, 14.5% and 25.9%, respectively. The reconstruction measures for rainwater and sewage mixed connection can make the groundwater infiltration managed to a certain extent. But the pipeline networks are operated at the high water level for a long time and the level of groundwater is higher. If the operation water level of sewage pipelines is reduced, the groundwater infiltration rate may increase. In 2022, the proportions of rainwater inflow for Branch 1, Branch 2 and Branch 3 were 0.4%, 0%, and 6.9%, respectively. And in 2023, they were 0%, 10.6% and 10.2%, respectively. With intensified efforts in initial rainwater management, the rainwater volume into separated sewer systems has increased.