CO2 Utilization in the Ironmaking and Steelmaking Process

Study on the resource utilization of CO2 is important for the reduction of CO2 emissions to cope with global warming and bring a beneficial metallurgical effect. In this paper, research on CO2 utilization in the sintering, blast furnace, converter, secondary refining, continuous casting, and smelting processes of stainless steel in recent years in China is carried out. Based on the foreign and domestic research and application status, the feasibility and metallurgical effects of CO2 utilization in the ferrous metallurgy process are analyzed. New techniques are shown, such as (1) flue gas circulating sintering, (2) blowing CO2 through a blast furnace tuyere and using CO2 as a pulverized coal carrier gas, (3) top and bottom blowing of CO2 in the converter, (4) ladle furnace and electric arc furnace bottom blowing of CO2, (5) CO2 as a continuous casting shielding gas, (6) CO2 for stainless steel smelting, and (7) CO2 circulation combustion. The prospects of CO2 application in the ferrous metallurgy process are widespread, and the quantity of CO2 utilization is expected to be more than 100 kg per ton of steel, although the large-scale industrial utilization of CO2 emissions is just beginning. It will facilitate the progress of metallurgical technology effectively and promote the energy conservation of the metallurgical industry strongly.