污水处理厂纳污片区排水污染源调查与进水浓度关联分析

Investigation of Drainage Pollution Sources and Correlation Analysis of Influent Concentration in Pollutant Receiving Area of Sewage Treatment Plant

住建等四部委要求到2025年进水BOD_(5)浓度高于100 mg/L的城市生活污水处理厂规模占比达90%以上。本文以截至2023年的城市污水厂进水浓度距国家考核目标还存在较大差距的南方某城市为例,了解该市主城区污水处理厂纳污范围排水单元污染物浓度情况,选取有代表性的污水处理厂内约40家典型排水单元,以BOD_(5)为监测对象,分不同时期对水质调查监测,分析与污水厂进水浓度的关联性,得出排水单元BOD_(5)平均浓度总体能达到100 mg/L的考核要求;不同类型排水单元污染物浓度差距不明显;冬季污水中污染物浓度较高;纳污范围内排水管网对污染物浓度削减作用明显等主要结论。同时针对问题,提出推进污水处理“源头减量”、“提质增效”;加强运维管护“清淤疏浚”、“低位运行”;加强后续监测,精准分析等管理建议,以期为相关行业主管部门后续工作提供数据支撑。

Four ministries and commissions such as housing and construction require that by 2025,the scale of urban domestic sewage treatment plants with influent BOD_(5) concentration higher than 100 mg/L will account for more than 90%.A southern city with a large gap between the influent concentration of urban sewage treatment plant and the national assessment target by 2023 was taken as an example to understand the pollutant concentration in the drainage unit of the sewage treatment plant in the main urban area of the city.About 40 typical drainage units in representative sewage treatment plants were selected,and BOD_(5) was used as the monitoring object.The water quality was investigated and monitored in different periods,and the correlation with the influent concentration of the sewage treatment plant was analyzed.It was concluded that the average concentration of BOD_(5) in the drainage unit could meet the assessment requirements of 100 mg/L,the difference of pollutant concentration in different types of drainage units was not obvious,the concentration of pollutants in sewage was high in winter.The main conclusions were that the drainage pipe network had obvious effect on the reduction of pollutant concentration in the range of pollution.At the same time,in view of the problems,it was proposed to promote the“source reduction”and“quality and efficiency improvement”of sewage treatment,strengthen operation and maintenance management“dredging”,“low-level operation”,strengthen follow-up monitoring,accurate analysis and other management recommendations,in order to provide data support for the follow-up work of relevant industry authorities.