沧州市降水化学组成及其对大气颗粒物的清除作用  

Chemical Composition of Precipitation and Its Scavenging Effect on Atmospheric Particulate Matter in Cangzhou City

作　　者：王剑[1] 侯启婧 郭蕊 徐美[1] 毛娜 赵亚楠 毛羽丰 庞亚恒 WANG Jian;HOU Qi-jing;GUO Rui;XU Mei;MAO Na;ZHAO Ya-nan;MAO Yu-feng;PANG Ya-heng(Department of Chemistry and Chemical Engineering,Cangzhou Normal University,Cangzhou,Hebei 061001,China;Cangzhou Municipal Research Institute of Environmental Protection,Cangzhou,Hebei 061001,China)

机构地区：[1]沧州师范学院化学与化工系,河北沧州061001 [2]沧州市生态环境保护科学研究院,河北沧州061001

出　　处：《沧州师范学院学报》2022年第1期19-24,共6页Journal of Cangzhou Normal University

基　　金：2021年沧州市重点研发计划指导项目“沧州市大气降水化学组成特征及来源分析”,编号:204107003;2020年沧州师范学院“滨海环境与生态科研创新团队”,编号:cxtdl1904;2020年沧州师范学院校内科研基金项目“沧州市大气降水污染特征研究”,编号:xnjjl1901.

摘　　要：基于2017年沧州市降水观测数据(pH值、电导率和水溶性离子浓度)及PM_(2.5)和PM_(10)质量浓度数据,分析了大气降水化学组成特征,并从降水总量、降水强度和降水时长3个角度探讨了不同类型降水对PM_(2.5)和PM_(10)的清除作用.结果表明:采样期间降水pH值变化范围为5.75~8.61,降水量加权均值为6.63,降水未发生酸化.电导率变化范围为10.79~361μs·cm^(-1),降水量加权均值为75.26μs·cm^(-1).降水离子总浓度变化范围为95.82~2519.19μeq·L^(-1),降雨量加权均值为785.36μeq·L^(-1).Ca^(2+)和NH_(4)^(+)是降水中主要阳离子,分别占阳离子总浓度的66.49%和13.63%.SO_(4)^(2-)和NO_(3)^(-)是降水中主要阴离子,分别占阴离子总量的63.49%和25.45%.降水对大气颗粒物有一定清除作用,降水日PM_(2.5)和PM_(10)质量浓度分别比非降水日降低34.41%和47.30%.降水对PM_(2.5)和PM_(10)清除效率随着降水总量、降水时长的增加而呈现增加趋势.同等降水条件下,降水对PM_(2.5)的清除效果要优于PM_(10).Based on the precipitation observation data,including pH value,electrical conductivity and water-soluble ion concentration,and the mass concentration data of PM_(2.5) and PM_(10) in Cangzhou in 2017,the chemical composition characteristics of atmospheric precipitation were analyzed,and the scavenging effects of different types of precipitation on PM_(2.5) and PM_(10) were studied from the aspects of total precipitation,precipitation intensity and precipitation duration.The results showed that the variation range of precipitation pH value during the sampling period was 5.75~8.61,and the volume-weighted mean of precipitation was 6.63,indicating that precipitation was not acidified.The variation range of electrical conductivity was 10.79~361μs·cm-1,and the volume-weighted mean of precipitation was 75.26μs·cm^(-1).The variation range of total ion concentration in precipitation was 95.82~2519.19μeq·L^(-1) and the volume-weighted mean of precipitation was 785.36μeq·L^(-1).Ca^(2+) and NH_(4)^(+) were the main cations in precipitation,accounting for 66.49% and 13.63% of the total cations concentration in precipitation,respectively.SO_(4)^(2-) and NO_(3)^(-) were the main anions in precipitation,which account for 63.49% and 25.45% of the total anions in precipitation,respectively.Precipitation had a certain scavenging effect on atmospheric particles,and the mass concentrations of P2.5 and PM_(10) on rainy days were 34.41% and 47.30% respectively,lower than those in non-rainy days.As the total precipitation grows in amount and time,so does the scavenging rate of atmospheric pollutants.Under the same precipitation conditions,the effect of precipitation on PM25 was better than PM_(10).

关 键 词：大气颗粒物 大气降水 清除作用 化学组成 沧州 

分 类 号：X513[环境科学与工程—环境工程] TQ09[化学工程]