河南省优先控制人为源VOCs关键物种及来源识别

Identification of Key Anthropogenic VOCs and Their Sources in Henan Province

为了解河南省人为源挥发性有机物(VOCs)的排放特征,识别以臭氧(O3)污染治理为目的的关键VOCs物种及其排放源,以五大类人为源活动水平数据为基础,采用排放因子法建立了2019年河南省县级人为源VOCs组分化排放清单,并利用最大增量反应活性(MIR)估算其臭氧生成潜势(OFP),基于OFP识别O3污染治理的关键VOCs物种及其排放源.结果表明:(1)河南省2019年人为源VOCs排放总量为175.62×10^(4)t,其中工艺过程源、移动源、生物质燃烧源、溶剂使用源和化石燃料燃烧源对VOCs排放总量的贡献率分别为28.6%、25.2%、20.8%、19.1%和6.3%.(2)空间分布显示,以郑州市为中心的豫北排放量远高于豫南,呈“一高三低”的空间分布特点,郑州市排放量最高,其排放量为27.7×10^(4)t,漯河市、三门峡市和鹤壁市排放量最低,其排放量均小于5.0×10^(4)t.(3)芳香烃是排放量最高的化学组分,其排放量为47.5×10^(4)t,其次为烷烃(46.3×10^(4)t)、OVOCs(40.3×10^(4)t)和烯烃(20.9×10^(4)t),其中甲苯、乙烯、苯等排放量高的10个物种占排放总量的42.0%.(4)河南省人为源VOCs的总OFP为664.0×10^(4)t,其中,芳香烃和烯烃对OFP的贡献最大,均占总OFP的32%,其次为OVOCs,占比为28.0%;本研究的OFP空间分布与国控点O3浓度和PM_(2.5)-O3大气复合污染空间分布规律高度一致.研究显示,乙烯、间/对-二甲苯、甲苯、丙烯和甲醛等对总OFP的贡献率为67.2%,其主要来源是生物质燃烧、小型客车、建筑涂装、汽车涂装、化学合成、涂料制造、建筑和农业机械等,因此这些VOCs物种和排放源是河南省O3污染治理的关键.

In order to understand the characteristics of VOCs emissions from anthropogenic sources in Henan Province,and to identify key VOCs types and their emission sources for O3pollution control,the county-level anthropogenic speciated VOCs emission inventory was established using the emission factor methods in 2019.Furthermore,the ozone formation potentials(OFP)of VOCs were estimated by Maximum Incremental Reactivity(MIR),and the key species and emission sources were identified based on OFPs.The results showed that:(1)The total anthropogenic VOCs emissions in Henan Province in 2019 were 175.62×10^(4)t,of which industrial sources,mobile sources,biomass combustion sources,solvent utilization sources,and fossil fuel combustion sources contributed 28.6%,25.2%,20.8%,19.1%,and 6.3%to the total VOCs emissions,respectively.(2)The spatial distribution showed that the emissions in northern Henan were much higher than those in southern Henan,and the spatial distribution of municipal emissions was characterized by’one high and three low’,with the highest emission of 27.6×10^(4)t in Zhengzhou City,the lowest emissions in Luohe,Sanmenxia,and less than 5.0×10^(4)t in Hebi.(3)Aromatic hydrocarbons were the highest emitted chemical component at 47.5×10^(4)t,followed by alkanes(46.3×10^(4)t),OVOCs(40.3×10^(4)t),and alkenes(20.9×10^(4)t),of which 10 species had high emissions,such as toluene,ethylene,and benzene accounted for42.0%of the total emissions.(4)The total OFP of anthropogenic VOCs in Henan Province was 664.0×10^(4)t,among which aromatic hydrocarbons and alkenes contributed the most to OFP,each accounting for 32%of the total OFP,followed by OVOCs(28.0%).The spatial distribution of OFP in this study is highly consistent with the spatial distribution of O3concentration and PM_(2.5)-O3air compound pollution obtained from National Air Quality Monitoring Stations.In summary,ethylene,m/p-xylene,toluene,propylene,and formaldehyde contributed for 67.2%of the total OFP,and they mainly came from biomass combustion,passenger cars,architectural painting,car painting,chemical synthesis,paint manufacturing,construction and agricultural machinery.These species and emission sources are the focus of ozone pollution control in Henan.