基于PMF模型的兰州市城关区VOCs来源解析研究OACSTPCD

To explore the pollution characteristics and sources of VOCs in Chengguan District of Lanzhou,the pollution characteristics of VOCs in Chengguan District of Lanzhou based on hourly VOCs component monitoring data in 2021 were analyzed.The positive matrix factorization method(PMF)was used to quantitatively analyze the sources of VOCs pollution in Chengguan District of Lanzhou.The results showed that the annual average concentration of VOCs species was 122.810 μ g/m3,and the contribution of VOCs species concentration from high to low was oxygen-containing compounds,alkanes,halogenated hydrocarbons,aromatic hydrocarbons,alkenes,and alkynes.VOCs mass concentration varied greatly in each season,showing the characteristics of high pollution in autumn and winter and low pollution in spring and summer.Most VOCs concentrations showed obvious bimodal diurnal variation in four seasons.The PMF source analysis results showed that there were 5 types of VOCs pollution sources in the whole year,with their contribution rates in descending order being solvent usage sources,vehicle exhaust sources,fixed combustion sources,process sources,and oil and gas volatilization sources.There were 5 types of pollution sources in spring,3 types in summer,4 types in autumn,and 5 types in winter,of which the contribution of each pollution source in summer was the source of solvent use,vehicle exhaust source and process source,and the contribution of each pollution source in winter was the source of solvent use,fixed combustion source,process process source,oil and gas volatilization source and vehicle exhaust source.