OPERATION OF BLAST FURNACE FOR PRODUCING LOW SI MOLTEN IRON

摘要

PROBLEM TO BE SOLVED: To stably produce a molten iron low in Si content by charging bulky coke excellent in gas permeability, fine granular coke, ore in order toward the furnace inner wall part from the furnace core part on coke layer in a furnace in the blast furnace operation. ;SOLUTION: At the time of charging and piling up coke used as a reducing agent and also as a heat source and iron ore, etc., in layer-state into a blast furnace, bulky coke 11 having good permeability is charged into the furnace center part having 0.2 dimensionless radius r/R (wherein, R is the furnace radius of furnace top part coke layer 11 and (r) is the radius of annular part of the charged fine granular coke 12 at the furnace top part) on the surface of the coke layer 10, and successively, the fine granular coke 12 having poor gas permeability is charged in the annular range having 0.2-0.3 dimensionless radius r/R outside the bulky coke, and successively, the ore 13 is charged between the fine granular coke 12 and the furnace inner wall 1. A liquid flowing position at the lower part of the furnace is concentrated near the furnace inner wall 1 while avoiding an adverse effect on the furnace condition, so as to prevent molten slag and SiO₂ in ash content of the coke from being reduced into Si to prevent the increase of Si content in the molten iron, thus the low Si pig iron is produced.;COPYRIGHT: (C)1997,JPO