Mathematical modelling of non-isothermal reduction in highly swelling iron ore–coal char composite pellet

Abstract A mathematical model of direct reduction in an iron ore–coal char composite pellet is presented. The model incorporates heat transfer, devolatilisation, pellet size change, and three reduction steps (hematite to magnetite, magnetite to wustite, wustite to iron) as well as carbon consumption during the reduction. The model predictions are in good agreement with experimental data. The effect of swelling and shrinkage on heat transfer and the reduction process is discussed.

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