太原市冬季气溶胶污染特征及来源分析

Analysis on the Sources and Characteristics of Particles in Winter in Taiyuan

2004年12月,使用美国PIXE公司的单孔分级式撞击采样仪,在太原市区进行大气颗粒物采样.使用质子X射线荧光法对样品进行了分析,得到20种元素的质量浓度及其谱分布,对太原市冬季气溶胶的化学特征和来源进行了研究.结果表明,在测到的大气颗粒物中,20种元素的质量浓度主要是由Al、Si、Ca、Fe、S五种元素贡献的,且粗粒子占优势.与历史资料对比,Ca、Ti、S、Cu、Pb等元素谱分布图变化不明显,表明来源变化不大;As、Se、Br三种元素由细粒单峰型变为三峰型谱分布,可能与局地扬尘有关;Al、V、K、Mn四种元素谱分布明显呈向细粒模态,表明来自人为源污染加重.大气颗粒物中Cu、Zn、Br、Pb等元素富集较高,尤其是在细粒子中,表明这些元素污染较重且主要来自人为源.因子分析结果表明,太原市大气颗粒物主要来源于土壤尘、冶金尘、燃煤尘.

Atmospheric particle samples were collected during December in Taiyuan, Shanxi, in the winter of 2004 and were analyzed by PIXE. 20 element concentrations and elemental distribution were obtained. According to the observation data of 1983, the element concentrations, elemental distribution and possible sources of atmospheric distributions of the elements such as Ca, Ti, S, Cu and Pb do not change much, while the size distributions of As, Se, Br have changed to be three peak values modle due to road dust, A1, V, K and Mn have changed to be fine mode due to anthropogenic sources. The enrichment factors of elements such as Cu, Zn, Br, Pb are very high due to heavy pollutions. Factor analysis further indicated that atmospheric particles in Taiyuan have three main sources ： the soil and dust, metallurgical industry, coal combustion.