Research Progress on Carbon Capture and Utilization Technology in Steel Industry

ObjectivesThe control of greenhouse gas emissions, mainly CO2, under the “carbon peak and carbon neutrality” target has received high attention. In 2023, China’s CO2 emissions ranked first in the world, with 12.6 billion tons. Among them, the steel industry is one of the main sources of CO2 emissions, accounting for about 15% of China’s CO2 emissions. China’s crude steel production accounts for more than half of the world’s total, and reducing carbon emissions in the steel industry requires consideration of China’s national conditions and energy utilization characteristics. Therefore, it is necessary to study the carbon capture and utilization technologies suitable for China’s steel industry.MethodsThe emission characteristics of CO2 in the steel production process are analyzed and the research progress of existing carbon capture technologies are summarized, with a focus on the application of absorption, adsorption, and membrane separation methods in CO2 capture of blast furnace gas. In addition, the utilization of top gas recycling-oxygen blast furnace technology is explored and its coupling potential with absorption and adsorption technologies is analyzed, in order to achieve low-carbon transformation in the steel industry.ConclusionsThe use of top gas recycling-oxygen blast furnace technology can be combined with absorption or adsorption methods to reduce carbon consumption and carbon emissions of the blast furnace, and the effective utilization of steel plant waste heat can help improve the economic feasibility of carbon capture. The integration of carbon capture and utilization in the steel industry can be realized by the combination of converter CO2 injection, steel slag mineralization and utilization, and tempering co-production of CO2 to produce chemical products technology. It can not only reduce the carbon emissions in the steel industry, but also improve the industry’s economic and environmental benefits through capacity optimization.