哈尔滨市大气中多环芳烃的初步研究

Polycyclic aromatic hydrocarbons in air of Harbin City

利用改进型的大流量主动采样器,于2008年5月7～20日对哈尔滨市大气样品进行采集,并检测了气相和颗粒相中的多环芳烃(PAHs)的浓度.结果表明,哈尔滨市大气中总PAHs的浓度为8.1～37.2ng/m3,平均值为18.2ng/m3.通过特征分子比值法推断出哈尔滨市大气中PAHs主要来自于煤的燃烧.低环PAHs主要集中在气相,而高环PAHs则吸附在颗粒相上.气粒分配系数与过冷饱和蒸气压具有很好的相关性,但PAHs并没有达到气粒分配平衡,这可能与冬季取暖用煤燃烧产生的新多环芳烃有关.

Air samples were collected using an improved high volume active air sampler in May 7 to 20,2008 in Harbin City.Concentrations of polycyclic aromatic hydrocarbons（PAHs） in both gas and particle phases were measured.Total PAHs concentration ranged from 8.1 to 37.2 ng/m3,with an average of 18.2 ng/m3 for all samples.Sources of PAHs were identified by diagnostic ratios of some individual PAHs,which indicated that the dominant source in Harbin was coal combustion.Lower ring PAHs dominated in the gas phase,while the major higher ring PAHs were adsorbed on particle phase.While good correlation was found between gas-particle partition coefficients of PAHs and the respective sub-cooled vapor pressures,non-equilibrium between gas and particle phases was obtained possibly due to the new produced PAHs from coal combustion in winter.