Influence of Hydrogen-Based Direct Reduction Shaft Furnace Interior Structure on Shaft Furnace Performance.

Hydrogen-based direct reduction of iron ore is a promising route to reduce CO2 emissions in steelmaking, where uniform particle flow inside shaft furnaces is essential for efficient operation. In this study, a full-scale three-dimensional Discrete Element Method (DEM) model of a shaft furnace was developed to investigate the effects of a diverter device on granular flow. By systematically varying the radial width and top/bottom diameters of the diverter, particle descent velocity, residence time, compressive force distribution, and collision energy dissipation were analyzed. The results demonstrate that introducing a diverter effectively suppresses funnel flow, prolongs residence time, and improves radial flow uniformity. Among the tested configurations, the smaller central diameter diverter showed the most favorable performance, achieving a faster and more uniform descent, reduced compressive force concentration, and lower collision energy dissipation. These findings highlight the critical role of diverter design in regulating particle dynamics and provide theoretical guidance for optimizing shaft furnace structures to enhance the efficiency of hydrogen-based direct reduction processes.