The daily monitoring data of influent water quality of seven wastewater treatment plants(WWTPs)in the main urban area of Nanjing from 2019 to 2021 were taken as the study object,and the time-series characteristics of pollutant concentration were analyzed systematically.The fluctuation period of water quality were identified by using the empirical mode decomposition,and the trends of water quality were diagnosed with seasonal and trend decomposition,and Mann-Kendall test.The main results were as follows.(1)The average concentrations of ammonia nitrogen,TN,TP and CODCr from the influent of WWTP in the main urban area were 24.74,29.47,3.08 mg/L and 214.85 mg/L,respectively.(2)The concentration of influent pollutants showed significant seasonal differences,with lower concentration in July and higher concentration in December.(3)CODCr of influent water from WWTPs in the main urban area had the strong upward trend,and the CODCr of four WWTPs presented the significant upward trends.(4)On the daily scale,the ammonia nitrogen,TN,TP and CODCr of influent water from each WWTP exhibited periodic oscillation with 3 days.The relevant results provide important data support for improving the operation efficiency of wastewater treatment in the study area.
关键词
南京市/污水处理厂/进水水质/时序特征/趋势/周期性
Key words
Nanjing/wastewater treatment plant/influent water quality/time-series characteristics/trend/periodic
维普
万方数据