基于单颗粒气溶胶质谱法的雾霾过程中细颗粒物组分分析及来源研究

Compositions and sources of fine particles measured by SPAMS method during a haze process

为了解雾霾过程中细颗粒物的组分与来源,采用单颗粒气溶胶质谱(SPAMS)法,于2015年12月在西安城市运动公园对雾霾过程进行连续观测。根据细颗粒物的质谱特征,将其化学组分分为10类,为有机碳(OC)、元素碳(EC)、混合碳(ECOC)、左旋葡聚糖(LEV)、矿尘(MD)、重金属(HM)、富钾颗粒物(RK)、富钾钠颗粒物(RNa K)、富铵颗粒物(RNH+4)以及其他颗粒物。将本次雾霾过程分为5个阶段,各个阶段占比最大的化学组分均为OC、EC、ECOC;在雾霾生长阶段,RK、RNa K及RNH+4增长明显。将细颗粒物来源分为8类:机动车(36.3%)、燃煤(22.5%)、扬尘(7.1%)、生物质燃烧(5.1%)、工业(7.3%)、餐饮(0.5%)、二次合成(7.9%)和其他来源(13.3%)。结果表明,机动车和燃煤是本次雾霾的主要来源,二次合成对雾霾生长和消退有重要作用。

To study the compositions and sources of the fine particles during a haze process,single partical aerosol mass spectrometer（ SPAMS） method was used for 12 d consecutive sampling in Xi＇an City Sports Park. The fine particles were divided into 10 categories according to the characteristic of the chemical compositions,which were organic carbon（ OC）,elemental carbon（ EC）,EC and OC mixed carbon（ ECOC）,levoglucosan（ LEV）,mine dust（ MD）,heavy metal（ HM）,particle rich in K（ RK）,particle rich in Na and K（ RNa K）,particle rich in NH＋4（ RNH＋4） and other particle. The haze process could be divided into 5 stages. The largest proportion chemical compositions of all stages were OC,EC and ECOC. The increase of RK,RNa K and RNH＋4was obviously in the haze growth stage. The fine particles were divided into 8categories according to the different sources,which were motor vehicles（ 36. 3%）,coal（ 22. 5%）,dust（ 7. 1%）,biomass burning（ 5. 1%）,industry（ 7. 3%）,food（ 0. 5%）,second synthesis（ 7. 9%） and other source（ 13. 3%）. The results showed that the main sources of this haze process were motor vehicles and coal,meanwhile,second synthesis played an important role in the growth and regression of the haze.