| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for operating a blast furnace, in which the COemission amount can be reduced drastically and pig iron can be produced stably for a long period of time in the commercial blast furnace.SOLUTION: The method for operating the blast furnace, from the top of which an iron source raw material and coke are charged and from a tuyere of whose lower part fine powdery coal is injected thereinto together with hot wind, comprises the steps of: injecting the reducing gas, which is of coke-oven gas and/or natural gas and has high hydrogen content, from the tuyere in the blast furnace lower part together with the hot wind and the fine powdery coal; and injecting the modified furnace top exhaust gas, which is obtained by removing the carbon dioxide content and the steam content from the gas to be discharged from the top of the blast furnace, into the blast furnace from the tuyere arranged in the blast furnace lower part and another tuyere arranged in the furnace middle stage part. |
