| 摘要 |
PROBLEM TO BE SOLVED: To provide a blast furnace operation method by which, in the blast furnace operation where large quantity of pellets are blended, a good furnace condition can be ensured by keeping air permeability at the upper part of the furnace independently of a change in a heat flow ratio. SOLUTION: There is provided the blast furnace operation method in which iron ore raw materials composed of: a pellet; sintered ore; and bulky ore, and coke, are alternately charged in a layer state. When the blending ratio of the pellet in the iron ore raw material is ≥15 mass%, the method satisfies the following expression 1. The expression 1; [C/S]≥U+0.575, wherein U: heat flow ratio=(the average specific heat of the charged materials in the blast furnace×the average density×the descended speed)/(the average specific heat of gas in the blast furnace×the gas density×the gas flowing speed), and [C/S]: the average mass ratio of CaO/SiO<SB>2</SB>in the iron ore raw material. COPYRIGHT: (C)2011,JPO&INPIT |
