Iron and Steel Slag - USGS Mineral Resources Programlacking. Shortly after, many markets for slags opened in. Europe, the United States, and elsewhere in the world. In the production of iron, the blast furnace (BF) is charged with iron ore, fluxing agents (usually line and/or dolomite), and coke as both fuel and reducing agent. The iron ore is a mixture of iron oxides, silica,.slag from iron ore processing in united states,iron and steel - EPAAccording to the U.S. Bureau of Mines, the iron and steel producers and ferrous foundries produced goods .. line to form a slag that absorbs much of the sulfur from the charge. Molten iron . In general, the process involves (1) beneficiation of the iron ore, (2) either direct-reduction or reduction in an iron blast furnace,.