摘要
采用再悬浮箱模拟得到不同粒径的烹调油烟、生物质和塑料燃烧烟尘、汽车尾气和发电机烟气等颗粒,并用GC/MS对不同粒径颗粒中18种多环芳烃(PAHs)进行了分析.结果表明,烹调油烟中颗粒物存在0.44~1.0μm和2.5-10μm两个峰值,稻草和木材燃烧排放烟尘只有0.44~1.0μm一个峰值,塑料燃烧排放烟尘的峰值不明显,汽车尾气尘因含有大量的水汽导致其粒径峰值出现在2.5~10μm,而发电机排放的烟尘约93%集中在≤2.5μm的粒径范同.烹调油烟和汽车尾气尘中低环数PAHs在2.5~10μm范围内的峰值明显;随环数增加,0.44~1.0μm范围内的峰值变得明显;不同排放源亚微米颗粒中单一PAH占全部颗粒态中该PAH的比例都呈现随分子量的增大而增大的趋势.烹调油烟和燃烧排放颗粒中PAHs的组成以菲占主导,但汽车尾气和发电机烟尘中含量最高的PAHs分别是萘和苯并[g,h,i]芤.来源特征比值的比较显示,烹调油烟与生物质燃烧颗粒中PAHs的源特征较为接近,但两者都不同于汽车尾气和发电机烟尘.
Particles from cooking lampblack, biomass and plastics burning smoke, gasoline vehicular exhausts and gasoline generator exhausts were prepared in a resuspension test chamber and collected using a cascade MOUDI impactor. A total of 18 polycyclic aromatic hydrocarbons (PAHs) associated with particles were analyzed by GC-MS. The results showed that there were two peaks in the range of 0.44- 1. 0 μm and 2.5-10 μm for cooking lampblack, and only one peak in the range of 0.44- 1.0μm for straw and wood burning smoke. But there were no clear peak for plastics burning smoke. The peak for gasoline vehicular exhausts was found in the range of 2.5-10μxm due to the influence of water vapor associated with particles, while the particles from gasoline generator exhausts were mainly in the range of ≤ 2.5 μm ( accounting for 93% of the total mass). The peak in 2.5- 10 μm was clear for cooking lampblack and gasoline vehicular exhausts. The peak in the range of 0.44-1.0 μm became more and more apparent with the increase of PAHs molecular weight. The fraction of PAH on particles less than 1.0 μm to that on the total particles increased along with PAH's molecular weight. Phenanthrene was the dominant compound for cooking lampblack and combustion smoke, while gasoline vehicular exhausts and generator exhausts were characterized with significantly high levels of naphthalene and benzo[ g, h, i ] perylene, respectively. The distribution of source characteristic ratios indicated that PAHs from cooking lampblack and biomass burning were close and they were different from those of vehicular exhausts and enerator exhausts.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2014年第1期46-52,共7页
Environmental Science
基金
国家自然科学基金项目(40971257
41171365)
环境保护公益性行业科研专项(201009004)
关键词
颗粒物
多环芳烃
排放源
粒径分布
环境效应
particles
PAHs
emission sources
size distribution
environment effects