Health risk assessment of exposure to selected volatile organic compounds emitted from an integrated iron and steel plant.

Workplace air samples from sintering, cokemaking, and hot and cold forming processes in the integrated iron and steel industry were analyzed to determine their volatile organic compound (VOC) concentration. Sixteen VOC species including three paraffins (cyclohexane, n-hexane, methylcyclohexane), five chlorinated VOC species (trichloroethylene, 1,1,1-trichloroethane, tetrachloroethylene, chlorobenzene, 1,4-dichlorobenzene), and eight aromatics (benzene, ethylbenzene, styrene, toluene, m,p-xylene, o-xylene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene) were selected to measure their noncancer risk for workers. Concentrations of toluene, xylene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, dichlorobenzene, and trichloroethylene were high in all four processes.

Adsorption characteristics of benzene on biosolid adsorbent.

This study selected biosolids from a petrochemical wastewater treatment plant as the raw material. The sludge was immersed in 0 to 5 mol l(-1) of ZnCl2 solutions and pyrolyzed at different temperatures. When the sludge was pyrolyzed for 30 min at temperatures of 400, 500, 600, and 700 degrees C, the corresponding surface area of the biosolid adsorbent was 46, 401, 921, and 727 m2/g, respectively.