| 银川市大气臭氧生成敏感性与VOCs来源解析 |
| 摘要点击 2451 全文点击 435 投稿时间：2023-08-07 修订日期：2023-11-01 |
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| 中文关键词 臭氧（O3） 臭氧敏感性分析 F0AM模型 VOCs来源解析 正定矩阵因子分解（PMF）模型 |
| 英文关键词 ozone （O3） ozone sensitivity analysis framework for 0-D atmospheric modeling（F0AM） VOCs source apportionment positive matrix factorization （PMF） model |
| DOI 10.13227/j.hjkx.20240805 |
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| 中文摘要 |
| 基于银川市2022年O3浓度观测数据,分析了O3浓度月变化特征,并基于5~7月银川市城区站点的气象要素、常规污染物和VOCs浓度观测数据,比较了污染日与非污染日的气象要素及前体物浓度的差异,并利用0维大气框架模型（F0AM）和正定矩阵因子分解（PMF）模型探讨了O3生成敏感性及VOCs主要来源.结果表明：①2022年银川市O3污染出现在5~7月, ρ（O3-8h-90per）分别为156、 170和174 μg·m-3,超标率分别为9.7%、 26.7%和29.0%. ②O3污染日的气温、太阳总辐射和各类前体物浓度小时均值相较于非污染日均有所升高,其中丙烷、异丁烷、乙烷、正丁烷和二氯甲烷体积分数较非O3污染时期增加显著,分别增加了33.1%、 29.1%、 25.0%、 22.7%和21.3%,污染物排放增加及不利气象条件共同促进了O3的生成. ③5~7月整体、非污染日和污染日VOCs物种OFP值排名前5的物种一致,均为乙醛、间/对-二甲苯、乙烯、异戊二烯和甲苯,主要来自溶剂使用源、天然源和化工行业排放. ④本地O3生成多处于VOCs控制区,相对增量反应活性（RIR）分析表明污染日和非污染日O3生成均对烯烃和芳香烃的敏感性较强,而NOx为负敏感性,丙酮、乙烯和异丁烷等活性物种对于O3生成的贡献较高,实施VOCs与NOx减排比例远大于1的减排方案可有效降低本地O3浓度. ⑤银川市大气VOCs主要来源为机动车排放源（32.3%）、工艺过程源（20.7%）、燃烧源（19.2%）、溶剂使用源（12.7%）、汽油挥发源（9.1%）和天然源（6%）,并且污染日机动车排放源贡献率较非污染日增加4.6%,说明机动车排放源是银川市夏季VOCs管控的重要对象. |
| 英文摘要 |
| Based on the observation data of O3 concentration in Yinchuan in 2022, the monthly variation characteristics of O3 concentrations were analyzed. Further, based on the observation data of meteorological elements, conventional pollutants, and volatile organic compounds （VOCs） concentrations at an urban site in Yinchuan from May to July, the difference in meteorological elements and precursor concentrations between the polluted days and the non-polluted days were compared. Then, the O3 sensitivity and the VOCs sources were discussed using the Framework for 0-D Atmospheric Modeling （F0AM） and positive matrix factorization （PMF） model, respectively. The results showed that： ① The O3 pollution occurred from May to July in 2022, and the concentrations of O3-8h-90per were 156 μg·m-3, 170 μg·m-3, and 174 μg·m-3, respectively, with exceeding standard rates of 9.7%, 26.7%, and 29.0%, respectively. ② Compared with those on the non-polluted days, the hourly mean values of temperature, total solar radiation, and concentrations of various precursors on the O3-polluted days increased, including the volume concentrations of propane, isobutane, ethane, n-butane, and dichloromethane, which increased significantly by 33.1%, 29.1%, 25.0%, 22.7%, and 21.3%, respectively. The results showed that the combined increase in pollutant emissions and adverse meteorological conditions contributed to the formation of O3. ③ From May to July 2022, the top five VOCs species in terms of ozone formation potential （OFP） value on whole, non-polluted, and polluted days were the same. They were acetaldehyde, m/p-xylene, ethylene, isoprene, and toluene, mainly from solvent use sources, natural sources, and chemical industry emissions. ④ The local O3 production was mostly controlled by VOCs, and the relative incremental reactivity （RIR） results revealed that O3 production showed strong positive sensitivity to alkene and aromatic hydrocarbon but showed negative sensitivity to NOx on both polluted and non-polluted days. The relative contributions of active species such as acetone, ethylene, and isobutane to O3 production were high, and the implementation of an emission reduction scheme with the ratio of VOCs to NOx emission reduction much greater than 1 could effectively reduce the local O3 concentration. ⑤ The main sources of atmospheric VOCs in Yinchuan were motor vehicle emission sources （32.3%）, process sources （20.7%）, combustion sources （19.2%）, solvent use sources （12.7%）, gasoline volatile sources （9.1%）, and natural sources （6%）, and the contribution rate of motor vehicle emission sources on polluted days increased by 4.6% compared with that on non-polluted days, indicating that the motor vehicle emission source was an important object of summer VOCs control in Yinchuan. |
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