嘉兴市大气VOCs特征及其对臭氧生成的影响研究

Characteristics of Atmospheric VOCs and Their Effects On Ozone Generation in Jiaxing City

为研究嘉兴市大气VOCs特征及其对臭氧生成的影响,采集了2022年1月、4月、7月和10月大气中114种VOCs物种,分析VOCs的浓度分布与组成特征,估算其臭氧生成潜势(OFP)。结果表明:嘉兴市大气VOCs平均体积浓度为38.74×10^(-9),OVOCs占比最高,各组分的体积浓度都在冬季呈现最高值。OPF均值为256.76μg/m^(3),芳香烃在各季节的OFP都最大,对OFP贡献最大的物种为甲苯、间/对—二甲苯、乙烯、丙烯、乙醛等,削减机动车排放和溶剂使用是嘉兴市控制O_(3)污染的关键。通过计算X/E(间/对—二甲苯和乙苯的体积浓度之比)和T/B(甲苯和苯的体积浓度之比),得出气团存在长距离传输现象,且受到溶剂挥发等VOCs排放源的影响更显著。

In order to study the characteristics of atmospheric VOCs and their effects on ozone generation in Jiaxing City,114 VOCs species in the atmosphere in January,April,July and October 2022 were collected;the concentration and composition characteristics of VOCs were analyzed;and their ozone formation potential(OFP)was estimated.The results showed that the average volume concentration of atmospheric VOCs in Jiaxing city was 38.74×10^(-9),and the proportion of OVOCs was the highest.The volume concentration of each component was the highest in winter.The average OPF in Jiaxing city was 256.76μg/m^(3),and the OFP of aromatic hydrocarbons was the highest in all seasons.The VOCs species that contributed the most to OFP were toluene,m-p-xylene,ethylene,propylene,acetaldehyde,etc.Reducing vehicle emissions and solvent use is the key to controlling O_(3) pollution in Jiaxing City.By calculating X/E(volume concentration ratio of m-p-xylene to ethylbenzene)and T/B(volume concentration ratio of toluene to benzene),it is concluded that the air mass has a long-distance transport,and it was more significantly affected by VOCs emission sources such as solvent volatilization.