摘要
采用在线监测设备对2020年9月武汉大气中光化学污染物PAN、O_(3)以及气象条件进行实时监测,对PAN和O_(3)变化特征和日变化规律进行分析,并将PAN和O_(3)体积分数与气象观测数据和后向轨迹相结合,综合分析输送特征以及污染状况。观测期间,武汉城区大气中PAN体积分数平均值为(0.68±0.53)×10^(-9),最大小时体积分数为2.79×10^(-9),O_(3)体积分数平均值为(54.56±22.44)×10^(-9),最大小时体积分数为108.73×10^(-9)。PAN与O_(3)间存在相似的日变化趋势,PAN与O_(3)均是碳氢化合物与氮氧化物光化学反应的产物,通过相关性分析PAN和O_(3)体积分数相关系数为R^(2)=0.61,城市大气中大多数反应性VOCs都能生成O_(3),而PAN仅由能产生CH_(3)CO_(3)自由基的VOCs反应生成;生成PAN的VOCs与臭氧产生潜势(OFP)共有物质有丙烷、乙烯、间,对-二甲苯、甲苯、邻二甲苯,这5种物种占OFP前十物种的67.6%,占生成PAN的VOCs前8物种的93.4%,理论上优先管控OFP前10物种对PAN和O_(3)防控均有较好效果,风玫瑰图显示共有5种污染物可能更多来自居地排放,且可能一定程度受外来传输的影响。
Online monitoring equipment is used to conduct real-time monitoring of photochemical pollutants acetyl nitrate ester peroxide(PAN),ozone(O_(3))and meteorological conditions in the atmosphere of Wuhan in September 2020.The variation characteristics and daily variation rules of PAN and O_(3)are analyzed,and the volume fractions of PAN and O_(3)are combined with meteorological observation data and backward trajectory.Transport characteristics and pollution status are analyzed comprehensively.During the observation period,the average PAN volume fraction in the atmosphere of Wuhan urban area is(0.68±0.53)×10^(-9);the maximum hourly volume fraction is 2.79×10^(-9),and the average O3 volume fraction is(54.56±22.44)×10^(-9).The maximum hourly volume fraction is 108.73×10^(-9).There is a similar diurnal variation trend between PAN and O_(3).Through correlation analysis,the volume fraction correlation coefficient between PAN and O_(3)is R^(2)=0.61.Both PAN and O_(3)are the products of photochemical reactions between hydrocarbons and nitrogen oxides,and their precursor VOCs are not identical,which is an important reason that affects their linear relationship.Most reactive VOCs in urban atmosphere can generate O_(3),while PAN is only generated by the reaction of VOCs that can generate CH_(3)CO_(3)radical.The common substances of PAN-producing VOCs and ozone producing potential(OFP)are propane,ethylene,meso-xylene,p-xylene,toluene and o-xylene.These five species account for 67.6%of the top ten species of OFP and 93.4%of the top eight species of PAN-producing VOCs.In theory,priority control of the top ten OFP species has a good effect on the control of PAN and O3.The wind rose diagram shows that there are five pollutants which may be more from local emission and may be affected by foreign transport to some extent.
作者
陈安雄
胡柯
李名升
尉红
钟章雄
段佳鹏
骆颖
Chen Anxiong;Hu Ke;Li Mingsheng;Wei Hong;Zhong Zhangxiong;Duan Jiapeng;Luo Ying(Wuhan Ecological Environment Monitoring Center,Wuhan,Hubei 430022,China;China Environmental Monitoring Station,Beijing 100012,China;Hangzhou Puyu Technology Development Co.,LTD.,Hangzhou,Zhejiang 310000,China)
出处
《绿色科技》
2023年第16期129-138,共10页
Journal of Green Science and Technology
关键词
PAN
O_(3)
光化学污染
武汉
peroxyacetyl nitrate(PAN)
Ozone(O_(3))
Wuhan
photochemical pollution
