To maintain smooth flow of molten pig iron by preventing adhesion of foreign matters, such as an oxide released from a scrap into the molten pig iron, onto a flow passage, when heating the molten pig iron to melt the scrap by using an induction heating device having the groove-type flow passage.
When melting a scrap 15 settled in a molten pig iron storing furnace 11 by conducting induction heating of molten pig iron 14 pooled in the molten pig iron storing furnace 11 using a groove-type induction heating device 21 having a flow passage 22, bubbles are blown into a bottom of the molten pig iron storing furnace 11 located between a settled position of the scrap 15 and the groove-type induction heating device 21 using a lance 41. A porous body 42 having a pore size of ≤20 μm is provided at a tip of the lance 41 to blow bubbles of 0.071 to 0.71 liter per minute per 1 ton molten pig iron.
MIKI YUJI
Megumi Konishi
Hide Tanaka Tetsu
Ichi Hirose
Toru Miyasaka