Abstract
A new ironmaking concept using iron-oxide-carbon composite pellets has been proposed, which involves the combination of a rotary hearth furnace (RHF) and an iron bath smelter. This part of the research focuses on studying the two primary chemical kinetic steps. Efforts have been made to experimentally measure the kinetics of the carbon gasification by CO2 and wüstite reduction by CO by isolating them from the influence of heat- and mass-transport steps. A combined reaction model was used to interpret the experimental data and determine the rate constants. Results showed that the reduction is likely to be influenced by the chemical kinetics of both carbon oxidation and wüstite reduction at the temperatures of interest. Devolatilized wood-charcoal was observed to be a far more reactive form of carbon in comparison to coal-char. Sintering of the iron-oxide at the high temperatures of interest was found to exert a considerable influence on the reactivity of wüstite by virtue of altering the internal pore surface area available for the reaction. Sintering was found to be predominant for highly porous oxides and less of an influence on the denser ores. It was found using an indirect measurement technique that the rate constants for wüstite reduction were higher for the porous iron-oxide than dense hematite ore at higher temperatures (>1423 K). Such an indirect mode of measurement was used to minimize the influence of sintering of the porous oxide at these temperatures.
Similar content being viewed by others
References
K.N. Pargeter, R.H. Hanewald, D.E. Dombrowski: Conserv. Recycl., 1985, vol. 8, pp. 363–75
O.M. Fortini: Ph.D. Thesis, Carnegie Mellon University, Pittsburgh, PA, 2004
S. Sun, W.-K. Lu: ISIJ Int., 1993, vol. 33 (10), pp. 1062–69
S. Sun, W.-K. Lu: ISIJ Int., 1999, vol. 39 (2), pp. 130–38
E.T. Turkdogan, J.V. Vinters: Carbon, 1969, vol. 7, pp. 101–17
E.T. Turkdogan, J.V. Vinters: Carbon, 1970, vol. 8, pp. 39–53
Y.K. Rao: Chem. Eng. Sci., 1974, vol. 29, pp. 1435–45
K. Otsuka, D. Kunii: J. Chem. Eng. Jpn., 1969, vol. 2, pp. 46–50
R.J. Fruehan: Metall. Trans. B, 1977, vol. 8B, pp. 279–86
C.E. Seaton, J.S. Foster, J. Velasco: Trans. Iron Steel Inst. Jpn., 1983, vol. 23, pp. 490–96
C. Bryk, W.-K. Lu: Ironmaking and Steelmaking, 1986, vol. 13, pp. 70–75
B.-H. Huang, W.-K. Lu: ISIJ Int., 1993, vol. 33 (10), pp. 1056–61
O.M. Fortini, R.J. Fruehan: Metall. Mater. Trans. B, 2005, vol. 36B, pp. 865–72
E.T. Turkdogan, R.G. Olsson, J.V. Vinters: Carbon, 1970, vol. 8, pp. 545–64
S. Dutta, C.Y. Wen, R.J. Belt: Ind. Eng. Chem. Res., Process Des. Dev., 1977, vol. 16, pp. 20–30
P.L. Walker, R.J. Foresti Jr., C.C. Wright: Ind. Eng. Chem. Res., 1953, vol. 45, pp. 1704–10
T. Adschiri, T. Shiraha, K. Ogawa, and T. Furusawa: Proc. Int. Conf. Coal Sci., 1985, pp. 289–92
J. Gadsby, F.J. Long, P. Sleightholm, K.W. Sykes: Proc. R. Soc. London, Ser. A, Math. Phys. Sci., 1948, vol. 193 (1034), pp. 357–76
A.E. Reif: J. Phys. Chem., 1952, vol. 36, pp. 785–88
E.T. Turkdogan, J.V. Vinters: Metall. Trans., 1972, vol. 3, pp. 1561–74
R.M. German: Sintering Theory and Practice, John Wiley and Sons, Inc., New York, NY, 1996
G.E. Hoffman, K.J. Shoop, and K. Tokuda: Ironmaking Conf. Proc., 1999, pp. 367–73
I. Sohn: Ph.D. Thesis, Carnegie Mellon University, Pittsburgh, PA, 2005
R.H. Tien, E.T. Turkdogan: Metall. Trans. B, 1977, vol. 8B, pp. 305–13
P.L. Walker, F. Rusinko, L.G. Austin: Adv. Catal. Relat. Subj., 1959, vol. 11, pp. 133–219
Acknowledgments
The authors thank the member companies of the Center for Iron and Steel Making Research (CISR) for the financing of this research. Also, special thanks to Dr. O.M. Fortini for helpful discussions.
Author information
Authors and Affiliations
Corresponding author
Additional information
Manuscript submitted April 4, 2008.
Rights and permissions
About this article
Cite this article
Halder, S., Fruehan, R. Reduction of Iron-Oxide-Carbon Composites: Part I. Estimation of the Rate Constants. Metall Mater Trans B 39, 784–795 (2008). https://doi.org/10.1007/s11663-008-9200-4
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11663-008-9200-4