Analysis of the impact of different rainfall scales on the water quality and quantity of municipal wastewater treatment plants
Based on the influent data of a municipal wastewater treatment plant in central Jian-gsu Province in 2021,the distribution of influent quality of municipal wastewater treatment plant was analyzed by using the methods of Shapolo-Wilke(S-W)test and triangle method.Combined with the rainfall data in 2021,the changes of biodegradability,rainwater mixing ratio and domestic sewage collection rate of sewage treatment plants under different rainfall scales were studied in or-der to provide data and scientific support for optimizing the operation and management of sewage treatment plants in rainy days.The results show that the influent COD of the sewage plant obeys the normal distribution,and the ammonia nitrogen,total nitrogen and total phosphorus are posi-tively skewed.With the increase of rainfall scale,the rainwater mixing rate increased from 11.1％to 19.7％,and the design scale of sewage treatment plant should be multiplied by a safety factor of 1.2.During moderate rain,the number of days in which the influent water quality of the sewage treatment plant is in good condition accounts for the highest proportion,and the biodegradability is the worst during heavy rain;the greater the rainfall is,the lower the collection rate of domestic sewage is.The collection rate of domestic sewage in flood season(June-August)is 20 percentage points lower than that in dry season(December-February).The collection and treatment of domestic sewage in June-August in flood season should be strengthened to reduce the discharge of domestic pollutants.
万方数据
维普
