Significant emissions from forming and finishing are limited to operations like reheat furnaces, scarfing, and pickling. Emissions from reheat furnaces include products of combustion, most of which are well controlled. Hand- or machine-scarfing of semifinished steel results in the release of a fine iron oxide fume. The major pollutants emitted during scarfing are iron and other oxides (FeO, Fe2O3, SiO2, CaO, and MgO). Acid mists arise from the hot acid baths used in acid pickling operations. Emissions from teeming and handscarfing are localized and usually uncontrolled.16 Hydrogen chloride (from hydrochloric acid pickling) is the primary hazardous air pollutant associated with pickling, with emissions from surface pickling typically over 10 t/yr/facility.6
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