Abstract
The Direct Reduction of Chromite (DRC) process has the potential to reduce energy consumption and reduce Greenhouse Gas (GHG) emissions for ferrochrome production, as needed to produce stainless steel and other specialty alloys. In the DRC process, Fe and Cr oxides in chromite are reduced at temperatures below their latent heat of fusion which substantially lowers energy requirements, resulting in the production of M7C3-type ferrochrome. In the present work, induration by oxidative sintering, reductant size, and reduction temperature were investigated at the exploratory level to advance our understanding of the DRC process. Induration by oxidative sintering was notably found to slow reaction kinetics and delay metallization, whereas smaller reductant sizes accelerate reaction kinetics. The influence of temperature on reaction kinetics was investigated in several experiments, and an energy barrier identified which may justify a DRC processing temperature of 1320 °C. After an extended time at 1320 °C, the amount of Cr present in the spinel and slag as measured by microprobe analysis are less than 0.43 wt% Cr as Cr2O3, which confirms high degrees of Cr metallization.
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Acknowledgments
This project has been funded by CanmetMINING, Natural Resources Canada, under the Critical Minerals Research, Development and Demonstration program. The authors would also like to thank Bhavya Bhatt and Chloe Castell for their assistance in conducting reduction experiments, as well as Derek Smith, and Dominique Duguay for their analyzing samples using XRD and Microprobe, respectively.
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Carter, D., Coumans, J.P., Paktunc, D. (2023). Advances in CaCl2-Assisted Direct Reduction of Chromite Processing. In: Proceedings of the 62nd Conference of Metallurgists, COM 2023. COM 2023. Springer, Cham. https://doi.org/10.1007/978-3-031-38141-6_111
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