| 摘要 |
PROBLEM TO BE SOLVED: To achieve the improvement of productivity and the lowering of fuel ratio in a blast furnace by securing the reducibility of a sintered ore when Al2O3 content in the sintered ore is high, raising an O/C ratio at the peripheral part of the furnace when a large quantity of pulverized fine coal is blown in, and improving the reducing efficiency in this zone. SOLUTION: In an operational method of the blast furnace, by which the pulverized fine coal is blown from a tuyere part of the blast furnace, and also, iron ore and coke are alternately charged from the furnace top part of the blast furnace, on either one of the upper layer or the lower layer of the iron ore, sintered ores respectively having <=0.3 and >=2.5 ratios (Al2O3/SiO2) of alumina and silica are dividedly charged into the peripheral part and the center part of the furnace, and on the upper part of the iron raw material layer of this sintered ore or the iron ore, the coke is charged to form a coke layer and, thereafter, this charging form is successively executed in this operation.
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