## 1 Introduction  
The ISI plays a crucial role in global economic advancement and industrial growth. Over recent decades, global steel consumption has experienced rapid expansion and is projected to reach 2.2 billion tons by the year 2050 [1]. The ISI is also one of the most energy-intensive and carbon-emitting industries. At present, the average energy consumption per ton of crude steel produced is 20 G) [2], and carbon dioxide emissions are in the range of 1.8-1.9 tons [3; 4]. The ISI contributes approximately 7% to global energy consumption and accounts for 7-9% of global carbon dioxide emissions [5; 6]. In the context of global warming and environmental degradation, the high energy consumption and significant carbon emissions associated with traditional production pose substantial challenges to the sustainable development of the ISI [7]. As such, a critical task in the ISI is to accelerate the transformation to green and low-carbon production. Currently, there exist two primary technical processes for steel production: the blast furnace-basic oxygen furnace (BF-BOF) process and the scrap/direct reduction iron-electric arc furnace (scrap/DRI-EAF) process. Together, these two methods account for over 95%of the world's total steel production [8; 9]. The traditional BF-BOF process is still the most widely used, accounting for about 70% of the world's total steel production [10]. In the BF-BOF process, about 80% of carbon dioxide emissions originate from the blast furnace ironmaking stage, primarily due to the substantial coal consumption involved [11]. Because coke plays an indispensable structural role in blast furnaces, the research of carbon emission reduction in blast furnace ironmaking has nearly reached a bottleneck [12; 13]. The scrap/DRI-EAF process is a typical \"non-blast furnace ironmaking\" process, where scrap steel or DRI is used as raw material. Compared with the BF-BOF process, the alternative process has shown clear preponderance in energy conservation and carbon emission reduction, leading to rapid development in recent years [14]. However, due to the limited availability of scrap steel resources, relying solely on scrap steel recycling cannot satisfy the rapidly growing global demand for steel [15]. Hence, there is an increasing demand for DRI produced by low-carbon technology [16]. The shaft furnace process plays an important role in DRI production, accounting for more than 72% of global DRI output [17]. The HDRSF approach integrates shaft furnace technology with hydrogen metallurgy. This approach reduces carbon emissions in DRI production at the source by using hydrogen to directly reduce iron ore, a process known as \"substitution of carbon with hydrogen\". This promotes cleaner production practices in the ISI [18]. The HDRSF-EAF process, which is a more mature technical route in the practical application of hydrogen metallurgy, can significantly reduce carbon emissions [19]. The flexible mixing ratio of reducing gases such as H\({}_{2}\) and CO also renders the HDRSF process more affordable [20]. Owing to the above characteristics, the HDRSF process is expected to be an important route for achieving the green and low-carbon development of the ISI in line with the concept of hydrogen metallurgy [21; 22; 23]. In recent years, China, the United States, Europe, and many other countries and regions have conducted research on the HDRSF process [24], thereby promoting its development and improvement. Hydrogen is a clean energy source that, when used in the reduction reaction with iron ore, produces only water vapor as a gaseous byproduct. This significantly reduces carbon emissions in steel production. According to calculations by [PERSON] et al.