Iron Ore Reduction with CO and H2 Gas Mixtures – Thermodynamic and Kinetic Modelling

The reduction of iron ore pellets has been studied using different techniques. Thermodynamic studies, experi-mental investigations and mathematical modelling have all been undertaken to better understand the behaviour of different pellet types in the new direct reduction process. The mathematical pellet model gives a good fit to most of the experimental conditions used in this work. There are some discrepancies between the experimental and calculated results under certain conditions, which are thought to be due to limitations in the experimental set up rather than fundamental issues in the model. The micromodel indicates that the hematite within the pellets is reduced to magnetite quickly, which in turn is reduced fairly quickly to wüstite. The reduction of wüstite to metallic iron seems to be the limiting stage in the reduction of the pellets, which is in line with what would be expected.