氢冶金的发展历程与关键问题

在“双碳”(碳达峰碳中和)战略背景下，以氢代碳的氢冶金成为钢铁企业优化能源结构和工艺流程、实现绿色低碳可持续发展的有效途径之一。以《联合国气候变化框架公约》和《京都议定书》的通过为时间节点，梳理和追溯了氢冶金的发展历程。从“以煤代焦、以气代焦”到“以氢代碳、以氢减碳”，铁矿石冶炼工艺由以减少焦炭和焦煤依赖为初衷，转变为以降低碳排放为重心，再到以净零碳排放为最终目标，逐渐形成高炉富氢冶炼和全氢直接还原工艺两大技术路线。从目前中国钢铁生产结构以及降碳目标来看，长流程产钢量占90%，高炉炼铁碳排放占比大、基数大。高炉低碳冶炼是规模化实现中国钢铁工业低碳的重要路径，而高炉富氢冶炼对“双碳”过渡时期的炼铁工业应用具有重要意义。从未来钢铁行业发展及能源结构转变来看，全氢直接还原工艺是实现钢铁行业净零碳排放的重要路线。发展氢冶金的关键问题包括如何解决绿色经济化制氢和安全规模化用氢。

Development and key problems of hydrogen metallurgy

Under the background of “carbon peaking and carbon neutrality”strategy, hydrogen metallurgy with hydrogen instead of carbon become one of the effective ways for iron and steel enterprises to realize green, low-carbon and sustainable development while optimizing energy structure and process flow. Sorting and tracing the development history of hydrogen metallurgy, taking the signing of the United Nations Framework Convention on climate change and the Kyoto Protocol as a time node, combined with the improvement of iron ore smelting process from “replacing coke with coal and gas” to “replacing carbon with hydrogen and reducing carbon with hydrogen”, the low-carbon transformation of ironmaking process is from reducing the dependence on coke and coking coal to focusing on reducing carbon emissions, and then to taking net zero carbon emissions as the ultimate goal, gradually forming two technical routes: hydrogen-rich smelting process of blast furnace and hydrogen based direct reduction process. According to the current production structure and carbon reduction goal of China's iron and steel industry, the blast furnace ironmaking process, which accounts for 90% of the output, emits a large proportion of carbon emissions. The low-carbon smelting of blast furnace is an important path to realize the low-carbon transformation of China's iron and steel industry. At the same time, the hydrogen-rich smelting of blast furnace is an important breakthrough path, which is of significance to the industrial application of ironmaking in the transition period of carbon peak and carbon neutrality. From the perspective of the future development of the iron and steel industry and the transformation of energy structure, hydrogen based direct reduction process is an important route to achieve net zero carbon emission in the iron and steel industry. At the same time, the key problems to be solved in the development of hydrogen metallurgy include green and economic hydrogen production and safe large-scale hydrogen use.