Chemical constituents in particulate emissions from an integrated iron and steel facility

Particle emissions from four integrated iron and steel plant processes, i.e., coke making, sintering, cold forming, and hot forming, were investigated in this study. Particle compositions of 21 element species, 11 ionic species, elemental carbon (EC), organic carbon (OC) and 16 polyaromatic hydrocarbons (PAHs) were analyzed to create “fingerprints” of the particles emitted from various processes in an integrated iron and steel plant. Results indicated that element compositions (0.11-0.42 g/g), water-soluble ions (0.34-0.52 g/g), elemental carbon (0.008-0.14 g/g), organic carbon (0.02-0.06 g/g) and PAHs (0.52-6.2 mg/g) contributed to the particle mass. In general, sulfur had a higher mass contribution than the other elements, which resulted from the use of coal, flux, heavy oil, and many recycled materials in the iron and steel plant. The particle mass contribution of potassium and chlorine in the sinter plant was higher than in other processes; this may be attributed to the lower boiling point and volatility of potassium. In addition, many recycled materials were fed into the sinter plant, causing a high concentration of potassium and chlorine in the particle phase. Eight PAH compounds were analyzed in the four processes. The carcinogenic compound Benzo(a)pyrene (BaP) was detectable only in the sintering process.