SMELTING REDUCTION OF IRON RAW MATERIAL AND SMELTING REDUCTION FURNACE

PROBLEM TO BE SOLVED: To provide a smelting reduction method of an iron raw material and a smelting reduction furnace, in which the reduction reaction is accelerated and iron or pig iron is efficiently produced, by promoting the mixing of carbonaceous materials and slag and the transfer of secondary combustion heat to the molten slag. SOLUTION: In the method for directly producing the molten iron or the molten pig by charging the iron raw material, a carbonaceous material and a slag-making material, and also, blowing oxygen and oxygen-containing air into a reaction vessel of the smelting reduction furnace composed of the reaction vessel 1 provided with upper tuyeres 14 and lower tuyeres 4 and a molten pig iron pool part and a slag pool part communicated with a siphon hole to execute the smelting reduction, the gaseous oxygen jet blown from the upper tuyeres 14 whose blowing height is freely changed, is blown so that the ratio L/Ls of cavity depth L developed in the molten slag 11a due to the collision with the gaseous oxygen jet to the thickness Ls of the slag which exists on the upper part from the lower tuyere 4 is 0.3-0.7.