Blast Furnace

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Blast furnace A furnace used for the primary reduction of iron ore to iron. Ore, coke, and limestone (which acts as a flux to remove silica) are loaded into the top of a tall furnace lined with mineral heat-resisting substances (such as fire-clay), in which the combustion of the coke is intensified by a pre-heated blast of air. At a certain temperature the iron ore is reduced to iron, which runs to the bottom of the furnace, where it is either tapped off and solidified as pig-iron, or conveyed while still molten to other plant for steel-making. >>

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