广州市中心城区污水处理厂进水水质分布规律研究

Distribution of Influent Quality of Sewage Treatment Plants in Guangzhou City Center

为落实城镇污水处理提质增效三年行动方案要求、了解广州市现状污水系统收集效能、摸清现状污水处理厂进水水质情况,以广州市10座城市污水处理厂2020年实际运行数据为基础,系统分析了进水水质特征及BOD_(5)、COD、NH_(3)-N的分布规律。结果表明,污水中BOD_(5)、COD、NH_(3)-N呈正偏态分布,中心城区进水BOD_(5)、COD、氨氮的中位数分别为97.35、175.00、17.60 mg/L,90%保证率下的BOD_(5)为139.00 mg/L、COD为262.00 mg/L、氨氮为23.30 mg/L。BOD_(5)/COD均值为0.545,中位数为0.548,比值超过0.4的百分比为96.8%,污水可生化性较好。降雨对污水厂进水水质有显著影响,其会降低污水处理厂削减污染物的效能,应继续加快推进渠箱清污分流及单元达标改造,降低雨水对污水系统收集处理效能的影响,保证进厂水质。

To implement the requirements of the three-year action plan for improving the quality and efficiency of urban sewage treatment, understand the collection efficiency of the current sewage system in Guangzhou, and find out the influent quality of the current sewage treatment plant, the characteristics of influent quality and the distribution of BOD_(5), COD and NH-N were systematically analyzed based on the actual operational data of 10 urban sewage treatment plants in Guangzhou in 2020.The BOD_(5), COD and NH-N in sewage were positively skewed. The median BOD_(5), COD and NH-N in downtown were 97.35 mg/L, 175.00 mg/L and 17.60 mg/L, respectively, and they were 139.00 mg/L,262.00 mg/L and 23.30 mg/L respectively at guarantee rate of 90%. The mean ratio of BOD_(5)to COD(BOD_(5)/COD) was 0.545, its median was 0.548, and the percentage of BOD_(5)/COD greater than 0.4 was 96.8%, indicating that the biodegradability of the sewage was good. Rainfall had a significant impact on the influent quality and reduced the pollutant reduction efficiency of the sewage treatment plant.Therefore, it is necessary to continue to accelerate the diversion of water and sewage in the combined tunnel and the transformation of the unit to meet the standard, and reduce the effect of rainwater on the collection and treatment efficiency of sewage system, so as to ensure the influent quality of the sewage treatment plant.