BLAST FURNACE OPERATION METHOD Russian patent published in 2023 - IPC C21B5/00 

FIELD: metallurgy.

SUBSTANCE: gas injection into a blast furnace. Hydrogen-rich gas containing 80 mol.% or more of hydrogen gas is blown in from the lance under the condition that the injection temperature of the hydrogen-rich gas is room temperature or more and 300°C or less, and the volume of hydrogen gas in the hydrogen-rich gas is 200 Nm³/t or more and 500 Nm³/t or less; condition in which the injection temperature of the hydrogen-rich gas is more than 300°C and 600°C or less, and the volume of hydrogen gas in the hydrogen-rich gas is 145 Nm³/t or more; condition in which the injection temperature of the hydrogen-rich gas is more than 600°C and 900°C or less, and the volume of hydrogen gas in the hydrogen-rich gas is 125 Nm³/t or more. Carbon flow in the furnace is changed by blowing in a hydrogen-rich gas containing 80 mol.% or more of hydrogen gas from a tuyere.

EFFECT: increase in the volume of gas having a high concentration of hydrogen blown from the lance as a reducing gas while maintaining stable operation of the blast furnace and reducing CO₂ emissions.

13 cl, 16 dwg, 3 tbl