Hostname: page-component-77c89778f8-5wvtr Total loading time: 0 Render date: 2024-07-21T20:09:17.115Z Has data issue: false hasContentIssue false

Effect of different factors on low temperature degradation of hematite iron ore during reduction

Published online by Cambridge University Press:  04 April 2014

A.J.B. Muwanguzi
Affiliation:
Department of Material Science and Engineering, KTH Royal Institute of Technology, Brinellvägen 23, 100 44 Stockholm, Sweden. e-mail: ajbm@kth.se
A.V. Karasev
Affiliation:
Department of Material Science and Engineering, KTH Royal Institute of Technology, Brinellvägen 23, 100 44 Stockholm, Sweden. e-mail: ajbm@kth.se
J.K. Byaruhanga
Affiliation:
Department of Mechanical Engineering, School of Engineering, College of Engineering Design Art and Technology, Makerere University, P.O. BOX 7062 Kampala, Uganda
P.G. Jönsson
Affiliation:
Department of Material Science and Engineering, KTH Royal Institute of Technology, Brinellvägen 23, 100 44 Stockholm, Sweden. e-mail: ajbm@kth.se
Get access

Abstract

Low temperature degradation (LTD) of iron oxides was investigated with the aim of understanding how natural iron ores degrade under different conditions. Minimisation of this degradation would increase the acceptance level of natural iron ores as feed materials without prior beneficiation. In addition to temperature and reduction gas composition, sample positioning in the reduction furnace and sample’s original weight were also found to influence LTD. Samples placed in the top reaction zone of the furnace, which have the first contact with the reducing gas, were found to degrade 1.5 times more than those in the middle and bottom reaction zones. In addition, they presented a wide range of size in the disintegrated particles than those in the middle and bottom reaction zones. Furthermore, the samples with an original weight equal to or greater than 5 g, had a disintegration extent of less than 10%. Therefore, if the reduction gas comes into contact with a certain material first, before contacting the iron oxide, it may serve to reduce on LTD during reduction. Furthermore, in laboratory conditions, the occurrence of low temperature breakdown of the natural iron oxides can be minimised by using samples with an original weight equal to or greater than 5 g.

Type
Research Article
Copyright
© EDP Sciences 2014

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Wu, S.L., Xu, H.F., Tian, Y.Q., Ironmaking and Steelmaking 36 (2009) 19-23
Shengl-Li, W., Xiao-qin, L., Qi, Z., Jian, X., Cheng-Song, L., J. Iron Steel Res. 18 (2011) 20-24
Brill-Edwards, H., Samuel, R.L., J. Iron Steel Institute 36 (1965) 361-368
Watanabe, S., Yoshinaga, M., TRANS- ACTIONS, Society of Mining Engineers 241 (1968) 1-15
Hasenack, N.A., Kister, H., Vogel, R.B., Van Toor, K.H., Society of Mining Engineers, AIME 260 (1976) 263-267
Padan, J.S., Singh, Onkar, Gupta, K.N., NML Technical Journal 20 (1978) 35-36
H.W. Gudenau, H. Walden, Investigations on the stability of iron ore pellets during low temperature reduction, 3rd International Symposium on Agglomeration, Nurnberg West Germany, 1981
Panigrahy, S.C., Rigaurd, M., Dilewijns, J., Iron and Steel International 57 (1984) 29-30, 32-33
Takada, T., Soma, H., Irita, T., Kamisaka, E., Isoyama, M., Suzawa, A., Transactions ISIJ 25 (1985) B-235
Adam, F., Dupre, B., Gleitzer, C., Solid State Ionics 32/33 (1989) 330-333
M. Naito, A. Okamoto, K. Nakamura, K. Yamaguchi, Nippon Steel, 1990
C.E. Loo, N.J. Bristow, Resistibility of iron ore sinters to low-temperature reduction degradation, 6th International Symposium on Agglomeration, Nagoya, 1993
H.P. Pimenta, V. Seshadri, T. de Aguiar Pacheco, A.T. Azevedo, Characterization of structure of blast furnace sinter and its behaviour during reduction at low temperatures, 6th International Symposium on Agglomeration, Nagoya, 1993
Loo, C.E., Bristow, N.J., Trans. Inst. Min. Metall. C 103 (1994) 91-168
Wenhui, Y., Iron and Steel 31 (1996) 41-44
Pimenta, H.P., Seshadri, V., Ironmaking and Steelmaking 29 (2002) 169-173
S.S. Gupta, B. Nandy, Tata Search, 2002
Iron ores for blast furnace feedstocks – Determination of low-temperature reduction-disintegration indices by static method – Part 2: Reduction with CO and N2. British Standards Institution, British Standard, BS ISO 4696-2:2007, London, 2007
Iron ores for blast furnace feedstocks – Determination of low-temperature reduction-disintegration indices by static method – Part 1: Reduction with CO, CO2, H2 and N2. Swedish Standards Institute, International Standard, ISO 4696-1:2007(E), Switzerland, 2007
Pineau, A. Kanari, N., Gaballah, I., Thermochim. Acta 447 (2006) 89-100
Bruce, D., Hancock, P., British Corrosion Journal 4 (1969) 221-222
Kumar, V., Jena, S., Patel, S.K., Mineral Processing and Extractive Metallurgy 29 (2008) 118-129