Study on the Appropriate Production Parameters of a Gas-injection Blast Furnace

The change regulations of the smelting parameters in a gas-injection blast furnace are investigated using theoretical calculations. The results show that when the volume of gas injected, the oxygen enrichment rate and the theoretical combustion temperature of tuyere are 600 m 3 /tHM, 10% and 1950~2200 ∘ C, respectively, the conditions meet the smelting requirements of a blast furnace. With the increase of the oxygen enrichment rate, the required air volume decreases, the contents of CO and H 2 in the top gas increase, and the content of CO 2 first increases and then decreases.With an increase of the volume of gas injected, the coke rate decreases. In addition, when the oxygen enrichment rate and the volume of gas injected are 10% and 600 m 3 /tHM, respectively, the CO content of the top gas constantly increases with the increase of the coke rate, while the H 2 and CO 2 contents both decrease. With the increase of the H 2 content in the gas, the direct reduction degree of iron gradually decreases and the volume shrinkage burden increases. Apparently, injecting gas into the blast furnace can prevent the theoretical combustion temperature from being too high and solve the contradiction between the upper cooling and lower heating of the blast furnace.