Mechanism and method for improving gas utilization rate of large blast furnaces based on data analysis

In response to the “dual-carbon” targets, optimizing blast furnace ironmaking processes has emerged as an urgent and critical pathway for achieving low-carbon smelting. Based on fundamental ironmaking principles, this study systematically investigates the 2021 operational data of 24 large blast furnaces in China (each with an effective volume exceeding 4000 m 3 ) to elucidate the intrinsic relationships between the gas utilization rate and its key influencing factors. Practical methods for improving the gas utilization rate are proposed and demonstrated through a case study of a large blast furnace at a Chinese steel enterprise, where fuel consumption was successfully reduced. The results show that, for blast furnaces operating at gas utilization rates below 50%, each 1% increase in the gas utilization rate leads to a reduction of 6–8 kg/t in fuel ratio and 4–5 kg/t in process energy consumption. Both theoretical analysis and operational verification confirm that enhancing the gas utilization rate is a crucial pathway toward low-carbon and high-efficiency blast furnace smelting.