Process for producing molten iron

摘要

A method for making molten iron includes the steps of feeding a raw material mixture containing an iron oxide material and a carbonaceous reductant into a heating reduction furnace to reduce iron oxide in the raw material mixture with the carbonaceous reductant into solid reduced iron; transporting the solid reduced iron to a melting furnace; and combustion of a carbonaceous material supplied as fuel to melt the solid reduced iron in the melting furnace for producing molten iron. After the metallization of the solid reduced iron is enhanced to at least 60%, the solid reduced iron is transported to the melting furnace. The amounts of oxygen and the carbonaceous material supplied to the melting furnace are controlled so that the secondary combustion ratio of Co gas in the melting furnace is reduced to 40% or less. The heat transfer efficiency of the secondary combustion heat to the molten iron is preferably increased to at least 60%.