关键词: 超低碳炼铁, 直接还原, 氢冶金, 电冶金, 氢气熔融还原

Abstract:

The carbon neutrality goal set by Chinese government in 2060 poses very strong constrains to the Chinese iron and steel industry on the one hand, and also provides a very good opportunity for the industry to compete with foreign counterparts on the other hand. In the present paper, the development history and technical status were analyzed for green hydrogen direct reduction, molten oxide electrolysis, electrowinning of iron in alkaline solution and electrowinning of iron in acid solution, etc. Under the scenario of sufficient low-cost green electricity, the theoretical and practical electricity consumption were evaluated for these routes together with the analyses about technique maturity, electricity consumption, technical difficulty and application prospect, etc. Through the analyses, it was found that the alkaline solution electrowinning of iron demonstrated the lowest electricity consumption, followed by the acid solution electrowinning of iron and the hydrogen smelting reduction with endothermic reaction heat provided by electricity. From technical point of view, the acid solution electrowinning of iron and the hydrogen direct reduction routes, both had completed pilot plant operation, were among the easiest to be implemented, while the hydrogen smelting reduction, alkaline solution electrowinning and the molten oxide electrolysis routes were still in the early stage of development. By the analyses, it was concluded that the acid solution electrowinning, the hydrogen direct reduction and the hydrogen smelting reduction routes were quite promising, while the molten oxide electrolysis and alkaline solution electrowinning were too challenging to be usable in 2060.

Key words: ultra-low-CO₂ ironmaking, direct reduction, hydrogen metallurgy, electrical metallurgy, hydrogen smelting reduction