Blast furnace operation method

A blast furnace operation method in which reducing gas including hydrogen atoms and carbon atoms is blown into a blast furnace, the method comprising:

• acquiring a correlation between a carbon consumption in the reducing gas and a reduction InputΔC by performing calculation using instances where molar ratio C/H in the reducing gas and an amount of the reducing gas blown are different from each other,
• wherein the InputΔC is defined as a proportion of reduction in specific carbon consumption Input C of an operation where a predetermined amount of reducing gas is blown with respect to a base operation where the reducing gas is not blown, and the Input C refers to the total mass of coke, pulverized coal, and carbon in the reducing gas for producing one ton of molten iron;
• determining a carbon consumption in the reducing gas where the reduction InputΔC in specific carbon consumption is a predetermined target value of the reduction InputΔC or higher on the basis of the correlation between the carbon consumption in the reducing gas and the reduction InputΔC acquired per the molar ratio C/H;
• and
• adjusting an amount of the reducing gas blown into the blast furnace on the basis of the determined carbon consumption in the reducing gas and a carbon proportion in the reducing gas,
• wherein the carbon consumption in the reducing gas is a value obtained by multiplying a carbon proportion kg/Nm3 in the reducing gas by the reducing gas volume Nm3/t-pig per ton of molten iron.