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Kinetics and Mechanism of Decarburization and Melting of Direct-Reduced Iron Pellets in Slag

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Abstract

An experimental study was conducted to understand the decarburization and melting behavior of direct-reduced iron (DRI) pellets in SiO2-Al2O3-CaO-MgO-FeO slags with various FeO concentrations (10 to 25 wt pct) and basicities (Bs), ranging from 1.5 to 2.5. The behavior of the pellet in slag was observed using the X-ray fluoroscopy technique; the rate of decarburization was simultaneously measured with a constant volume pressure increase technique. The study shows that the decarburization of DRI in slag at 1600 °C takes place in two stages. The first stage is the reaction between the FeO and the carbon inside the pellet, which is controlled by heat transfer from the slag to the pellet; the second stage involves the decarburization reaction between the FeO in the slag and the remaining carbon in the DRI. The kinetics of this stage is determined by the mass transfer of FeO in the slag and is strongly dependent on the FeO concentration. Depending on the physicochemical properties of the slag and the rate of gas evolution, the DRI may sink through, float inside the slag, or remain on top before complete decarburization.

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References

  1. World Direct Reduction Statistics–2007, Midrex, Charlotte, NC, 2006, pp. 2–4

  2. S. Montague and W.D. Hausler: Direct from Midrex, Midrex, Charlotte, NC, 1999, 4th qu., pp. 3–7

  3. R. Bailey: Direct from Midrex, Midrex, Charlotte, NC, 2001, 2nd qu., pp. 7–8

  4. S.C. Montague and W.D. Haysler: Proc. 57th Electric Furnace Conf., Pittsburgh, PA, 1999, pp. 607–14

  5. G. Whitten: Direct from Midrex, Midrex, Charlotte, NC, 1998, 3rd qu., pp. 3–5

  6. D. Quintero Yanez: Proc. 4th Eur. Electric Steel Congr., Madrid, Spain, 1992, pp. 273–83

  7. P.E. Duarte, R. Lopez: Iron Steel Eng., 1996, vol. 73 (11), pp. 38–41

    Google Scholar 

  8. F.M. Wheeler and Y.M. Gordon: Proc. 7th Eur. Electric Steelmaking Conf., Venice, Italy, Associazione Italiana di Metallurgia, Italy, 2002, pp. 2.437–2.446

  9. F.M. Wheeler and Y.M. Gordon: Proc. ISSTech Conf., Indianapolis, IN, Iron and Steel Society, Warrendale, PA, 2003, pp. 1033–41

  10. Y. Gordon and F. Wheeler: U.S. Patent No. 6,785,251, 2005

  11. F. Wheeler, F. Atkinson, Y. Gordon, S. Broek, V. So, and M. Barati: 3rd Int. Conf. Process Development in Iron and Steelmaking, MEFOS, Lulea, Sweden, 2008

  12. J. Li, M. Barati, and Y. Yang: Proc. 4th Int. Congr. on the Science and Technology of Steelmaking (ICS 2008), Iron and Steel Institute of Japan, Gifu, Japan, Oct. 6–8, 2008

  13. K. Sadrnezhaad, J.F. Elliott: Iron Steel Int., 1980, vol. 53 (6), pp. 327–39

    CAS  Google Scholar 

  14. K. Sadrnezhaad: Iron Steel Int., 1981, vol. 54 (6), pp. 309–14

    CAS  Google Scholar 

  15. D.A. Goldstein, R.J. Fruehan, B. Ozturk: Iron Steelmaker, 1999, vol. 26 (2), pp. 49–61

    Google Scholar 

  16. D.J. Min, R.J. Fruehan: Metall. Trans. B, 1992, vol. 23B, pp. 29–37

    Article  ADS  CAS  Google Scholar 

  17. B. Sarma, A.W. Cramb, R.J. Fruehan: Metall. Mater. Trans. B, 1996, vol. 27B, pp. 717–31

    Article  ADS  CAS  Google Scholar 

  18. N. Siddiqi, B. Bhoi, R.K. Paramguru, V. Sahajwalla, O. Ostrovski: Ironmaking and Steelmaking, 2000, vol. 27 (5), pp. 367–72

    Article  CAS  Google Scholar 

  19. R.D. Morales, R. Lule, F. Lopez, J. Camacho, J.A. Romero: ISIJ Int., 1995, vol. 35, pp. 1054–62

    Article  CAS  Google Scholar 

  20. R.J. Fruehan: Metall. Mater. Trans. B, 1997, vol. 28B, pp. 743–53

    Article  CAS  Google Scholar 

  21. D.J. Min, J.W. Han, W.S. Chung: Metall. Mater. Trans. B, 1999, vol. 30B, pp. 215–21

    Article  CAS  Google Scholar 

  22. G. Urbain, F. Cambier, M. Deletter, M.R. Anseau: Trans. J. Br. Ceram. Soc., 1981, vol. 80, pp. 139–41

    CAS  Google Scholar 

  23. R. Roscoe: Br. J. Appl. Phys., 1952, vol. 3, pp. 267–69

    Article  ADS  Google Scholar 

  24. K.C. Mills, B.J. Keene: Int. Mater. Rev., 1987, vol. 32, pp. 1–120

    CAS  Google Scholar 

  25. C.W. Bale, P. Chartrand, S.A. Degterov, G. Eriksson, K. Hack, R. Ben Mahfoud, J. Melançon, A.D. Pelton, S. Petersen: Calphad, 2002, vol. 26, pp. 189–228

    Article  CAS  Google Scholar 

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Acknowledgments

The authors acknowledge the Hatch and Ontario Centres of Excellence, for providing funding of this research (Grant No. MP50479). The authors also appreciate the assistance by Dr. F. Ji and Ms. E. Chen from McMaster University (Hamilton, ON) for setting up the experimental furnace and the X-ray machine.

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Author notes

  1. Jianghua Li (Postdoctoral Fellow, Research Engineer)

    Present address: AK Steel Corporation, Middletown, OH, USA

Authors and Affiliations

  1. Department of Materials Science and Engineering, University of Toronto, M5S 3E4, Toronto, ON, Canada

    Jianghua Li (Postdoctoral Fellow, Research Engineer) & Mansoor Barati (Assistant Professor)

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  1. Jianghua Li
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  2. Mansoor Barati
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Correspondence to Mansoor Barati.

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Manuscript submitted June 2, 2008.

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Li, J., Barati, M. Kinetics and Mechanism of Decarburization and Melting of Direct-Reduced Iron Pellets in Slag. Metall Mater Trans B 40, 17–24 (2009). https://doi.org/10.1007/s11663-008-9195-x

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  • DOI: https://doi.org/10.1007/s11663-008-9195-x

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