In this paper, the research status of the thermal state, reduction mechanism of iron-bearing burden, coke degradation behavior, and formation of the cohesive zone in various areas of blast furnace after hydrogen-rich smelting is summarized, which can make a more clear and comprehensive understanding for the effect of H2 on blast furnace ironmaking.

First, using a certain proportion of DRI in the smelting process of high-quality steel in EAF can improve the mechanical properties and overall quality of high-quality steel. At the same time, reasonable control of the application proportion of DRI can achieve the purpose of energy saving and increase in production, which is of great significance to improving the comprehensive benefits of EAF steelmaking. Second, the application of DRI in BF steelmaking can reduce the coke ratio of BF steelmaking and increase the output of BF steelmaking. The economic benefits of BF steelmaking are greatly improved.

The tunnel kiln process is relatively simple, the technical content is low, and the raw materials, reducing agents, and fuels are easy to solve. The process has strong practicability, small early investment, and is suitable for small-scale production. It is a metallurgical reduction production process commonly used in the powder metallurgy industry.