Characteristics and Source Apportionment of Carbon Components in Road Dust in Anshan

Abstract

In order to study the characteristics and sources of carbon fractions in PM2.5 in road dust in Anshan, road dust samples were collected from nine roads in Anshan in October 2014 and re-suspended on filters using a NK-ZXF sampler to obtain PM2.5 samples. A thermal optical carbon analyzer (IMPROVE-TOR) was employed to measure the mass fraction of organic carbon (OC) and elemental carbon (EC) in PM2.5. The results showed that ω(TC) in PM2.5 in road dust was 9.78% (outer loop)-14.00% (Qianshan West Road), ω(OC) was 8.15% (outer loop)-10.84% (Qianshan West Road), and ω(EC) was 1.63% (outer loop)-2.85% (Qianshan West Road). ω(OC) was much higher than ω(EC), indicating that road dust contained a large amount of organic carbon. All OC/EC values were greater than 2.0 during the sampling period, suggesting that there was secondary pollution. Spearman correlation analysis and linear fitting indicated that the sources of OC and EC were basically the same. Cluster analysis results showed that carbon components in PM2.5 in road dust in Anshan mainly originated from vehicle exhaust, biomass burning, and coal combustion emissions.