哈尔滨大气PM2.5中人为源元素化学组成特征及来源

应用场发射扫描电镜(FESEM)和电感藕合等离子(ICP-MS)技术对2007年哈尔滨市市区四季所采集的PM2.5样品进行了研究。图像分析和粒度分析表明:PM2.5的颗粒类型主要为矿物颗粒、飞灰颗粒和烟尘集合体,数量—粒度呈双峰分布,峰值出现在0.2～0.5μm和1.0～2.5μm之间。其中飞灰颗粒的数量占总颗粒数量的26%,体积只占颗粒总体积的3%,即PM2.5中细颗粒主要为飞灰颗粒。元素分析和富集因子分析表明,颗粒中所测的58种元素中有Cd、Sn、Tl、Te、Bi、V、Pb、Sb、Zn、As、Ag、In、Mo、Cu、Ga、Cr、W 17种元素在颗粒中得到富集,来自人为源,且燃煤源为主要贡献者。因子分析显示冶金排放、垃圾焚烧、汽车尾气源及动力与机电工业排放源也是明显的贡献者。

Chemical composition characteristics and origin of artificial pollution elements in PM2.5 in Harbin

The paper is concerned with the study of PM2.5 samples collected in Harbin in the four seasons,2007 using high resolution field emission scanning electron microscopy(FESEM) and inductive coupling plasma mass spectrometry(ICP-MS),coupled with the identification of particles in the PM2.5,including minerals,coal fly ashes and soot aggregates using morphology and size distribution technology.Number-size distribution of PM2.5 is of a bimodal pattern with the peak in 0.2 ～ 0.5 μm and 1.0 ～ 2.5 μm range.The fly ash occupies 26% by number and accounts for up to 3% by volume,an indication that the particles consist mainly of fly ash in the PM2.5.The analysis of elements and the enrichment factors shows that the elements of Cd、Sn、Tl、Te、Bi、V、Pb、Sb、Zn、As、Ag、In、Mo、Cu、Ga、Cr、W were enriched in the PM2.5,which was mainly released by combustion of coal.The factor analysis indicate that PM2.5 of Harbin comes from the metallurgical discharge,waste combustion,automobile exhaust,mechanical,and electrical industry discharge.