To establish an operational method which can efficiently preheat iron source without developing any trouble with the facility in an iron source supplying device, in an arc furnace providing a preheating vessel connected with the arc furnace.
In the arc furnace operational method by blowing gaseous oxygen and a prescribed quantity of carbonaceous material corresponding to this oxygen quantity into molten steel or molten slat in the arc furnace 1 and also, preheating the iron source 8 filled in the preheating vessel 7 with exhaust gas produced from the arc furnace to melt the preheated iron source, the preheating vessel is arranged by connecting with the arc furnace. The iron source preheated in the preheating vessel is directly supplied into the arc furnace from the preheating vessel through an iron source supplying device 12 and also, the oxygen blowing quantity into the molten steel or the molten slag is made to 37-45 Nm3/ton of the total molten steel melted in the furnace.
NAKAYAMA TAKESHI
MIZUKAMI HIDEAKI
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