[Characteristics Research on Carbonaceous Component of Particulate Matter Emitted from Iron and Steel Industry]

In order to investigate the carbonaceous characteristics of particles emitted from the iron and steel industry, an electrical low-pressure impactor (ELPI) was used to collect three sets of samples from the sintering process and one set of samples from the ironmaking process emissions of particulate matters. Organic carbon (OC) and elemental carbon (EC), which were divided into seven carbonaceous components based on the temperature of the particulate matter, were analyzed using a thermal-light reflection method. Results show that OC in sintering process particles is higher than that in ironmaking particles and accounts for 5.3%±2.3% and 7.1%±3.0% of PM₁₀ and PM_2.5, respectively, which reveals that OC tended to be enriched in fine particles. In the ironmaking process particles, OC accounted for 2.5% and 2.0% of PM₁₀ and PM_2.5, respectively. The relative proportions of the seven carbonaceous components in the four sets of samples were very similar. OC2 and OC3 accounted for the highest proportion; the EC1, EC2, and EC3 contents decreased in turn; and OC1 may be associated with boiler scale and desulfurization. In addition, the OC and EC of sintering process particles had higher correlation, and the OC/EC value of primary emission particles was 4.7±0.7, which is much higher than the value of the secondary OC estimation index in environment. Analyzing deeply on the carbonaceous characteristics in particles emitted from the iron and steel industry, which will provide essential data for source apportionment of carbonaceous aerosols in environment and will be conducive to the follow supervisory of pollution cleaning in iron and steel industry.