Application of a combined model to study the source apportionment of PM10 in Taiyuan, China

Abstract

Twenty four-hour averaged concentrations of ambient PM10 were collected in Taiyuan, China from April 2001 to January 2002. A sum of 14 chemical species in PM10 was analyzed and a combined receptor model (PCA/MLR-CMB) was applied to this speciation data to determine the contributions of major source categories. On stage 1, two factors were extracted by Principle Component Analysis/Multiple Linear Regression (PCA/MLR), while some unknown sources were excluded from the model as un-extracted factors. Each factor might contain more than one actual source categories and was identified as extracted complex source (EC-source). The actual source categories contained in each EC-source were investigated according to the factor loadings and emission inventory. On stage 2, the two EC-sources were separately used as new receptors, and their corresponding actual sources were apportioned by Chemical Mass Balance (CMB). Although near colinearity existing in some source profiles, a total of eight sources were still well estimated: resuspended dust (about 26%), coal combustion (about 18%), cement dust (about 5%), steel manufacture (about 12%), soil dust (about 7%), vehicle exhaust (about 13%), secondary sulfate (about 12%) and secondary nitrate (about 4%). The combined model resolved 97% of PM10 mass concentrations and the evaluation analysis showed the results obtained by the combined model were reasonable. © Taiwan Association for Aerosol Research.