石家庄市PM_(10)和PM_(2.5)中多环芳烃的分布及来源分析

于2013年春、夏、秋、冬四季采集石家庄市6个采样点PM10和PM2.5样品,分析其中的多环芳烃,研究了石家庄市PM10和PM2.5中PAHs在不同季节的污染水平、组成特征和主要来源。结果表明,石家庄市PM10和PM2.5中有15种PAHs检出,全年PM10中PAHs的质量浓度为7.5~510.5ng/m3,PM2.5中PAHs的质量浓度为3.6~460.6ng/m3;PAHs浓度季节变化明显,冬季浓度明显高于其他季节。春、夏、秋、冬四季PM10和PM2.5中的PAHs主要分布在细粒子中。4环和5环化合物是PAHs的主要成分,占比为66%~79%。与其他季节相比,冬季4环PAHs的含量高,5环和6环PAHs的比例相对低。运用比值法综合分析,石家庄市PM10和PM2.5中PAHs在冬季主要受到燃煤污染源的贡献,在春、夏、秋季,受燃煤污染和机动车污染综合作用。

Distribution and source analysis of polycyclic aromatic hydrocarbons in PM10 and PM2.5 in Shijiazhuang City

PM10and PM2.5samples were collected at 6sampling sites of Shijiazhuang in spring,summer,autumn and winter in2013 and polycyclic aromatic hydrocarbons(PAHs)in them were determined.The pollution levels,composition characteristics and main source of PAHs in PM10 and PM2.5in different seasons of Shijiazhuang were studied.It shows that there are 15 kinds of PAHs detected in PM10 and PM2.5in Shijiazhuang.The PAHs concentration in PM10 is from 7.5to 510.5ng/m3,and the PAHs concentration in PM2.5concentration is from 3.6to 460.62ng/m3;there is a significant seasonal change of PAHS concentration and the concentration in winter is obviously higher than in other seasons.The 4-ring and 5-ring compounds are the dominant species in PM10 and PM2.5in spring,summer,autumn and winter which accounts for 66%~79%.Compared with other seasons,4-ring PAHs in winter PAHs ratio is higher,5-ring and 6-ring PAHs in winter PAHs ratio are relatively lower than in other seasons.A comprehensive analysis using diagnostic ratio method proves that the PAHs in PM10 and PM2.5is mainly caused by coal-burning source in winter,while caused by the comprehensive effect of coal-burning and motor vehicle sources in spring,summer and autumn in Shijiazhuang City.