A Review on the Kinetics of Iron Ore Reduction by Hydrogen

A clean energy revolution is occurring across the world. As iron and steelmaking have a tremendous impact on the amount of CO2 emissions, there is an increasing attraction towards improving the green footprint of iron and steel production. Among reducing agents, hydrogen has shown a great potential to be replaced with fossil fuels and to decarbonize the steelmaking processes. Although hydrogen is in great supply on earth, extracting pure H-2 from its compound is costly. Therefore, it is crucial to calculate the partial pressure of H-2 with the aid of reduction reaction kinetics to limit the costs. This review summarizes the studies of critical parameters to determine the kinetics of reduction. The variables considered were temperature, iron ore type (magnetite, hematite, goethite), H-2/CO ratio, porosity, flow rate, the concentration of diluent (He, Ar, N-2), gas utility, annealing before reduction, and pressure. In fact, increasing temperature, H-2/CO ratio, hydrogen flow rate and hematite percentage in feed leads to a higher reduction rate. In addition, the controlling kinetics models and the impact of the mentioned parameters on them investigated and compared, concluding chemical reaction at the interfaces and diffusion of hydrogen through the iron oxide particle are the most common kinetics controlling models.

Automated summary

This review focuses on the current research status of improving the green production of iron and steel industry, emphasizing the potential of hydrogen in steelmaking processes and cost control, and lists the key parameters affecting reduction kinetics. The research results show that increasing temperature, H-2/CO ratio, hydrogen flow rate, and hematite percentage can increase the reduction rate.