改造国内污水管网系统需要综合考虑的四个因素:定量分析

Four factors need to be considered to improve and upgrade current sewer systems in China:Quantitative analysis

污水管网外来水入侵、管网污水收集率、市政用水量和污水处理厂处理量是影响城市污水系统和城市水环境质量的四个主要因素。污水系统改造不仅提升污染物收集率和污水管网中污染物(如COD)浓度,同时直接影响到对受纳水体的污染物排放溢流负荷。使用简化的城市污水系统模型和国内外实际数据,定量表征和讨论了四个因素对污水管网污水COD浓度和排放到受纳水体的溢流污染物负荷的影响,并就污水稀释倍数、污水处理厂处理量、污染物去除效率、排放标准和溢流排放负荷之间的多重对应关系进行了分析和讨论,根据国内现状,提出改造和升级污水管网及污水处理厂需要考虑的三点建议。

The extraneous water intrusion,sewage collection ratio,water consumption and treatment capacity of wastewater treatment plants are four factors influencing the performance and efficiency of urban sewage systems.By using a simplified urban sewerage system model and mass balance principle this paper quantitatively displayed and discussed the effects of the four factors on the COD concentration in sewers and pollutant overflow load to receiving water bodies.The interrelated multiple relationships among the sewage dilution factor,treatment capacity,pollutant removal efficiency,discharge standards of the wastewater treatment plant and the discharge COD load to the receiving waterbodies are exhibited and analyzed.The objectives is to help to understand in a quantitatively and systematic manner,the current situation of the sewage system,wastewater treatment plant and receiving waterbodies,and to combine with the capacities of financial resources,management and technology and the length of project implementing period,the through comparison of multiple options to identify the governing factor(s)and finally,formulate the most cost-effective approaches to improve the performance of urban sewer systems and protection of urban aquatic environment.