合肥市臭氧污染特征分析

Characteristics of Ozone Pollution in Hefei

利用合肥市环境空气质量监测和气象观测数据,重点分析了合肥市2022年9月份O_(3)的污染特征。结果表明:合肥市月度O_(3)污染呈双峰特征,日间污染呈单峰特征,日间污染存在持续时间拉长特征。O_(3)激光雷达显示,合肥市O_(3)污染主要分布在1.4 km以下,且多为本地光化学生成,存在O_(3)污染传输和夜间O_(3)残留影响,O_(3)生成时间主要集中在9:00~15:00,凌晨存在高空O_(3)沉降影响。通过VOCs/NO x比值法和O_(3)/NO x比值法均反映合肥市9月份O_(3)污染为VOCs控制;排放量较大的VOCs物质主要为烷烃,其中单个排放最大的物质是丙酮;115种VOCs对O_(3)的生成潜势平均贡献达到129.1μg/m^(3);醛酮类是对O_(3)生成贡献最大的关键活性组分,对O_(3)生成潜势的贡献为40.1%,说明控丙酮、乙醛、乙烷、正戊烷等物质可以有效控制O_(3)污染。

Using air quality monitoring data and meteorological observations in Hefei,the characteristics of O_(3) pollution in Hefei in September 2022 were analyzed.The results showed that the monthly O_(3) pollution in Hefei presented double peaks.The daytime pollution presented single peaks and the duration of the daytime pollution was prolonged.The ozone lidar showed that the O_(3) pollution in Hefei was mainly distributed below 1.4 km,and most of the pollution was local photochemical production.The ozone generation time mainly concentrated from 9 am to 15 pm.The early morning had the high altitude O_(3) subsidence influence.VOCs/NO x and O_(3)/NO x ratio method were used to show that this continuous ozone pollution was VOCs control.The major VOCs emitted were alkanes.The single largest emission species was acetone.The average contribution of 115 VOCs to O_(3) formation potential was 129.1μg/m^(3).Aldehydes and ketones were the most important active components,which contributed 40.1%to the potential of O_(3) formation.The results showed that the control of acetone,acetaldehyde,ethane,n-pentane and other species could effectively control O_(3) pollution.