SMELTING REDUCTION METHOD FOR IRON ORE

PURPOSE:To improve OD ratio and heat conductive efficiency and also to prevent the delay of reduction velocity of iron ore and becoming in excess of T.Fe quantity in slag by specifying pressure in a reduction furnace in the subject method with an iron bath type smelting reduction furnace. CONSTITUTION:The iron ore and carbonaceous material is supplied in a reduction furnace 1 and O2 gas is blown on the slag 8 through a lance 2 inserted in the furnace 1 and stirring gas of N2, etc., is blown into the iron bath 7 through blowing holes 3 arranged at the bottom and/or side wall of the furnace. C in the molten iron and C in the carbonaceous material are reacted with the blown O2 to change the generated CO into CO2 and combustion heat is conducted into the iron bath 7 and by reducing the iron ore, molten iron is produced. In this case, the pressure in the furnace 1 is kept to 0.3-6.0kg/cm G. By this method, superficial velocity in a column for generated gas is reduced, and by reducing scattering quantity of the carbonaceous material supplying in the furnace, the OD ratio can be improved, and also as transmission of heat generated with secondary combustion into the iron bath is sufficiently executed, the heat conductive efficiency can be improved.