练江流域污水处理厂污染物去除深度及其对地表站断面水质效能影响的研究

Study on Pollutant Removal Status of Sewage Treatment Plant in Lianjiang River Basin and its Impact on Water Quality Efficiency of Surface Station of Cross-section

经过中央环保督查回头看,及其后开展的练江整治工作,2020年,练江实现从普遍性黑臭到国考断面消除劣Ⅴ类、再提升至Ⅳ类的重大转折性变化。本文选取练江流域有代表性的13座污水处理厂,就其2021年度生产情况,对其进水水质特性、主要污染物的去除效果及处理成本进行了分析。发现污水厂进水水质浓度高于广东省同类污水处理厂,进水B/C值范围为0.34~0.50,进水B/N值范围为1.45~3.13,进水B/P值范围为14.5~30.83,进水可生化性较好,但碳源普遍不足,需增加碳源以实现脱氮的需要。同时,出水水质均能达到《练江流域水污染物排放标准》(DB44/2051-2017)。在枯水期,污水处理厂排水占练江径流比重大,直接关系着断面指标。除总氮外,污水处理厂目前的处理深度不构成断面达标的限制性因素。在丰水期,处理不及的污水溢流是断面局部时段超标的原因,雨污分流成为断面持续改善的必由之路。

After the Central Environmental Protection Inspector look,and then carried out the work of rectifying,Lianjiang River will achieve a major turning point from universal black odor to the elimination of inferior V.class,and then to IV,in 2020.In this paper,13 representative sewage treatment plants in the Lianjiang River Basin are selected to analyze the water quality characteristics of the inlet water,the removal effect of major pollutants and the treatment cost of their production in 2021.It is found that the water quality concentration of the inlet water of the sewage plant was higher than that of similar sewage treatment plants in Guangdong Province,and the B/C value of the inlet water of the sewage plant ranges from 0.34 to 0.50,the B/N value of the inlet water ranges from 1.45 to 3.13,and the B/P value of the inlet water ranges from 14.5 to 30.83,the biochemical properties of the inlet water are good,the carbon source is generally insufficient,and the carbon source needs to be increased to achieve nitrogen removal.At the same time,the effluent quality can meet the“Discharge Standard of Water Pollutants for Lianjiang River”(DB44/2051-2017).In the dry season,the drainage of sewage treatment plants accounts for a significant proportion of Lianjiang River runoff,which directly affects the river cross-section index.Except total nitrogen,the current treatment depth of the sewage treatment plants do not constitute a limiting factor for the river cross-section to meet the standard.In the wet season,the overflow of untreated sewage is the reason for exceeding the standard in some sections,and the diversion of rain and sewage has become the only way for the continuous improvement of the river cross-section.