PURPOSE: To remove molten irons of different components from the same blast furnace by providing a partition wall between the opening end on the furnace inner side of a part of tap hole out of plural pieces of the tap holes of the blast furnace and the central part in the well part of a hearth, and blowing SiO2- contg. powdery material and heavy oil through the tuyere in the position corresponding to said partition wall.
CONSTITUTION: A furnace body provided partition wall 9 in correspondence to a tap hole 6A out of a pair of tap holes 6A, 6B is used, and SiO2-contg. powdery material and heavy oil are blown independently or jointly through the tuyere 2A in the position ocrresponding to the wall 9. If, for example, SiO2-contg. powdery material is blown, the SiO2 in a raceway part 3A is enriched, hence the concn. of Si in the molten iron 4A dropping in the part 3A is increased. This results in that the concns. of Si in the molten irons 4A, 4A' removed through the tap holes 6A, 6B differ.
HAYASE KOUICHI
SAWADA TOSHIROU
