Influence of an Electromagnetic Field on Direct Reduction of Iron Oxide Using Hydrogen as a Reducing Agent

This work investigates the effect of electromagnetic fields (EMF) of varying frequencies on the reduction process of iron oxides and industrial iron ore in a hydrogen atmosphere using thermogravimetric analysis. Both extremely low‐frequency (50 Hz) and middle‐frequency (25 kHz) EMFs were found to increase the reduction degree and accelerate the reduction reaction compared with experiments without EMF. The application of extremely low‐frequency EMF did not cause additional thermal heating of investigated samples. However, with middle‐frequency EMF, heating of charged material was observed, which was effectively compensated for by the furnace's automatic power regulation. Experiments with industrial iron ore confirmed that EMF application had a positive effect on reduction process even above the Curie temperature, indicating that the effect is not governed by magnetic properties of iron. These findings demonstrate that EMF‐assisted hydrogen reduction can enhance reaction kinetics and reduce hydrogen consumption, offering a promising pathway toward more energy‐efficient and sustainable steelmaking.