Abstract
A new iron-making process using carburized pre-reduced iron ore pellets and microwave heating is investigated. The pre-reduced pellets, with a porous structure, and fine particles are carburized homogeneously at 400–650 °C in a CO atmosphere. The carburized carbon not only acts reaction as a reduction agent, but also absorbs microwave in the reduction process. Hence, the carburized pre-reduced pellets can be rapidly reduced by microwave heating. There are three procedures involved in the process, namely, gas-based pre-reduction, low-temperature carburization and deep reduction by microwave heating. Carburized pre-reduced iron ore pellets show a rapid temperature rise that is twice as fast as the results for pre-reduced pellets in the laboratory. This not only improves the efficiency of the microwave heating, but also accelerates the reduction of iron oxides. The temperature of the pre-reduced pellets rises to 1050 °C in 45 min when the carburization rate is 2.02%, and the metallization rate and compressive strength reach 94.24% and 1725 N/pellet, respectively.
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Foundation item: Project(NCET-04-0748) supported by the New Century Excellent Talent Planning of China
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Hu, B., Huang, Zc., Yi, Ly. et al. Direct reduction of carburized pre-reduced pellets by microwave heating. J. Cent. South Univ. 21, 351–357 (2014). https://doi.org/10.1007/s11771-014-1947-y
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DOI: https://doi.org/10.1007/s11771-014-1947-y