Abstract: According to the analysis and assumption of the low-carbon development of the iron and steel industry， the future iron and steel production and manufacturing processes will gradually evolve into three categories： blast furnace-converter long process， all-scrap electric arc furnace short process and hydrogen metallurgy-electric furnace process.The key factors affecting the carbon emission level of the three types of processes include process structure， raw material structure， energy structure， product structure， equipment level， management level， technical level， etc. This paper uses the "carbon peak and carbon neutrality" analysis model （CISRI-CPCN） constructed by China Iron and Steel Research Institute to draw a carbon reduction roadmap for the three types of processes.The research results show that the carbon emission of the three types of processes decreases annually. From 2020 to 2060， the CO2 emission of the long process will be reduced from 2.0 t/t （steel） to 0.87 t/t （steel）， and carbon neutrality can be achieved through carbon sinks， carbon trading and other means. In 2050， the short process will be reduced from 0.45 t/t （steel） to close to 0， which is expected to achieve "near-zero carbon" smelting. In 2060， the hydrogen metallurgical electric arc furnace process （50% scrap steel + 50% hydrogen direct reduced iron raw material structure） will be reduced from 1.31 t/t （steel） to close to 0， basically achieving carbon neutrality. Comprehensively considering the development needs of the national economy， it is recommended that the steel industry gradually adjust the product structure of the three types of processes in the development of steel industry  reduction in the future. The product structure of the long process should gradually transform into the production of flat products， especially high-end flat products， which are mainly distributed in coastal deep-water port areas. The short process should take the long products for construction as the entry point， gradually replace the small and medium-sized blast furnace-converter process， and partially produce single varieties such as combined steel and other high-quality special steel or stainless steel， mainly in the layout around cities with rich scrap steel resources. At present， the hydrogen metallurgy-electric furnace process is still in the stage of exploration and development， and many difficulties in green hydrogen， economy， technical reliability and engineering needed to be overcome.

Key words: Steel Manufacturing, Process Structure, All-scrap Electric Furnace, Hydrogen Metallurgy, Low-carbon Development

摘要： 根据对钢铁行业低碳发展的分析和设想，未来钢铁生产制造流程将在减量化发展进程中，逐渐演变为高炉-转炉长流程、全废钢电弧炉短流程和氢冶金-电弧炉流程三大类。影响三类钢铁生产制造流程碳排放水平的关键因素包括流程结构、原料结构、能源结构、产品结构、装备水平、管理水平、技术水平等。采用中国钢研构建的双碳分析模型（CISRI-CPCN），绘制了三类流程的降碳路线图。研究结果表明，三类流程碳排放量逐年降低。从2020―2060年，长流程的CO2排放量从2.0 t/t（钢）降低到0.87 t/t（钢），可通过碳汇、碳交易等手段实现碳中和。2050年短流程从0.45 t/t（钢）降低到接近0，有望实现“近零碳”冶炼。2060年氢冶金电弧炉流程（50%废钢+50%HDRI原料结构）从1.31 t/t（钢）降低到接近0，基本实现碳中和。综合考虑国民经济的发展需求，建议未来钢铁行业在减量化发展过程中，对三类流程的产品结构进行逐步调整。长流程的产品结构应逐步过渡到以生产平材产品为主，特别是高端板材，主要布局在沿海深水港地区。短流程应以建筑用长材为切入口，逐步替代中小高炉-转炉流程，部分生产合结钢等优特钢或不锈钢等单一品种，主要布局在废钢资源丰富的城市周边。目前氢冶金-电弧炉流程尚处于探索和开发阶段，需要克服其在绿氢、经济性、技术可靠性以及工程化等方面的诸多困难。

关键词: 钢铁制造, 流程结构, 全废钢电弧炉, 氢冶金, 低碳发展