摘要
为研究南京市大气细颗粒物(PM_(2.5))污染来源,分别在3个点位、4个季节开展了PM_(2.5)环境样品的采集,共获得170个有效样本对样本进行了化学成分分析,包括Al、Fe、Na、Mg、K、Ba、Li、Tl、Mn、Co、Ni、Cu、Zn、Sb、Pb、Cr、Ce、Na^+、NH_4^+、Mg^(2+)、Ca^(2+)、SO_4^(2-)、NO_3^-、Cl^-、以及OC,EC,共计26种,首先采用OC/EC最小比值法估算出二次有机气溶胶(SOA)的含量;然后利用正矩阵因子分解法(PMF)对PM_(2.5)的非SOA部分进行来源解析,共解析出6类因子:二次无机气溶胶(SIA),燃煤、机动车排放、地面扬尘、冶金和其它源,贡献率分别25.0%、23.5%、20.4%、17.1%、3.0%和11.0%;最后基于南京市SO_2、NO_x、VOCs三种主要前体污染物的排放量,分别对SIA和SOA在一次来源中进行再分配最终结果表明,南京市PM_(2.5)主要来源为燃煤、机动车、扬尘、工业和其它源,其贡献率分别为29.6%,22.4%、14.6%、18.7%和14.7%.
In order to identify the main emission sources of fine particulate matter(PM_(2.5)) in Nanjing,a total of 170 ambient samples were collected at three receptors and in four typical seasons.Chemical compositions were analyzed,including Al,Fe,Na,Mg,K,Ba,Li,Tl,Mn,Co,Ni,Cu,Zn,Sb,Pb,Cr,Ce,Na~+,NH_4~+,Mg^(2+),Ca^(2+),SO_4^(2-),NO_3^-,Cl^-,organic carbon(OC) and element carbon(EC).First,secondary organic aerosol(SOA) was estimated by using the OC/EC minimum ratio method.Then,the positive matrix factorization(PMF) model was applied for source apportionment basing on the non-SOA compositions.The PMF indicated six contribution factors of PM2.5,which are secondary inorganic aerosol(SIA,25.0%),coal combustion(23.5%),motor vehicle(20.4%),airborne soil(17.1%),metal processing(3.0%)and undefined sources(11.0%).Furthermore,based on the total emissions of SO_2,NO_x and VOCs in Nanjing,which are major precursors of secondary aerosols,the SIA and SOA were further apportioned among the primary sources.Final results show that the main sources of PM_(2.5) in Nanjing are coal combustion,motor vehicle,airborne soil,industry and others,with contributions of 29.6%,22.4%,14.6%,18.7%and 14.7%,respectively.
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2015年第12期3535-3542,共8页
China Environmental Science
基金
国家科技支撑项目(2011BAK21B03)
国家自然科学基金项目(41271511)