广州市大气中颗粒态多环芳烃(PAHs)的主要污染源

Source analysis and apportionment of particulate phase polycyclic aromatic hydrocarbons(PAHs) in Guangzhou City

采用特征化合物与因子分析对广州市大气中颗粒态PAHs的来源及其贡献率进行研究.结果表明,广州大气中颗粒态多环芳烃主要来源是机动车尾气排放和燃煤,其中机动车为主要污染源,占了69%,其次为燃煤,占了31%.冬季大气中颗粒态多环芳烃污染加重的主要原因为低温、无风的气象条件下形成的逆温效应,主要污染源为机动车的尾气排放;夏季颗粒态多环芳烃污染的增大同样是无风时不利于污染物扩散的结果,但此时燃煤对大气中颗粒态多环芳烃污染的贡献要略大于机动车尾气排放.

Based on the pooled data from a year-round weekly monitoring of PAHs in particulate phase in Luhu Lake, Guangzhou, the source apportionment of PAHs in particulate phases was studied using diagnostic ratios and principal component factor analysis (PCA). The result showed that the predominant sources for particulate phase were vehicle emissions and coal combustion. For total PAHs in particulates, vehicle emissions and coal combustion accounted for 69% and 31%, respectively. Higher concentrations of particulate PAHs in winter were likely due to increased emission from motor vehicle under low temperature driving conditions and to the influence of meteorological parameters such as slower wind speed and lower temperature. However, in summer high concentrations of PAHs were due to the higher emission of coal combustion and slower wind speeds. 