To provide a reduced iron producing apparatus, in which heated exhaust gas at a lower step is introduced to an upper step and utilized for drying and preheating and the whole apparatus is compact and has good thermal efficiency, by constituting the inner part of a reducing furnace onto the upper and the lower two steps.
Rotary furnace hearths rotating in the reducing furnace are constituted by piling to two upper and lower steps. Further, the rotary furnace hearth 22 at the upper step is smaller shape and rotated at higher speed than the rotary furnace hearth 24 at the lower step and in the rotary furnace hearth 22 at the upper step, a charging hole 21 for charging treating material 10 composed of iron ore powder containing coal and a carrying means 26 to the rotary furnace hearth 24 at the lower step, are arranged. Further, in the rotary furnace hearth 24 at the lower step, an ejector 8 for ejecting the treated material 10 and a combustion device 3 for heating the treating material 10, are arranged. The combustion gas generated at the rotary furnace hearth 24 at the lower step is introduced into the rotary furnace hearth 22 at the upper step to dry the treating material 10 on the rotary furnace hearth 22 at the upper step.
HIRATA KOICHI
NAKAJIMA HIROSHI
