PURPOSE: To produce a metal having constant quality and temp. by controlling metal oxide quantity at the predetermined reduction rate of the metal oxide, at the time of melting molten metal by injecting hot blast from the upper and lower two-step tuyeres and the metal oxide from the upper step tuyere at the same time in a vertical type furnace packed with carbonaceous reducing agent.
CONSTITUTION: High temp. air is injected through a distributor 4 from the upper and lower two-step tuyeres 5, 6 and also, the oxide-containing raw material of Fe and Cr is injected from the upper step tuyere 5 in the vertical type furnace 1 packed with carbonaceous reducing agent of coke, etc., by a blower 2 and a high temp. generator 3. In this case, the reaction rate of reducing this raw material to the Cr-containing molten iron is pre-determined, and by controlling the injecting velocity of the raw material so as to be proportional to this reducing reaction rate and be inversely proportional to the concn. of the metal oxide in the raw material, the Cr-containing molten iron having little variation in impurity content of Si, etc., and uniform concn. is produced.
KUSAKABE TARO
SATO KAZUHIKO
MOMOKAWA HIDEYUKI
ITAYA HIROSHI
