Selection and key technologies of low-carbon steelmaking processes under the background of “Double Carbon”

“Carbon peaking” and “carbon neutralization” are macro concepts that provide a general theoretical framework and basic ideas for China’s future economic and environmental development. Based on the in-depth analysis of the “double carbon” goal, China’s iron and steel industry is in a “carbon lock” state. Only by carrying out technological and institutional changes simultaneously can the “carbon unlock” be realized. The reasonable carbon peak time and peak value are given when the current production structure of the iron and steel industry, supply of smelting raw materials, smelting energy, energy conservation, emission reduction level, and CO₂ emission status are combined. In the next two or three decades, the main process of China’s iron and steel production is still the coexistence of long process and short process. Hydrogen metallurgy technology is still difficult to carry out in industrial production. The main measure to reduce carbon emissions is to increase the proportion of all scrap short process steelmaking. In the long run, it is generally accepted that the ironmaking process in the long term will gradually change from carbon reduction to hydrogen reduction. For the ironmaking process, the products will change from the original high-carbon molten iron to low-carbon molten iron or DRI. Converter steelmaking with high decarburization has no obvious advantages, and the development of the EAF steelmaking process is an inevitable choice. However, the realization of “carbon neutralization” depends on the development and application of hydrogen metallurgy, carbon capture, utilization, and storage technology, and the reform of the system. Based on an in-depth study of the theoretical research, equipment development, and practice of all scrap electric arc furnaces in recent years, aiming at the problems existing in the smelting process of all scrap electric arc furnaces, a series of key technologies have been developed to meet the current continuous casting production process rhythm and liquid steel quality control under the condition of all scrap, to provide theoretical support for the development of all scrap electric arc furnace.