Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-14T07:23:09.956Z Has data issue: false hasContentIssue false
  • English
  • Français

Kinetic parameters associated with self-heating of New Zealand coals under adiabatic conditions

Published online by Cambridge University Press:  05 July 2018

B. B. Beamish ,
J. D. St. George  and
M. A. Barakat
B. B. Beamish*
Affiliation:
Division of Mining and Minerals Process Engineering, The University of Queensland, Brisbane 4072, Australia
J. D. St. George
Affiliation:
Department of Civil and Resource Engineering, The University of Auckland, Auckland, New Zealand
M. A. Barakat
Affiliation:
Department of Civil and Resource Engineering, The University of Auckland, Auckland, New Zealand
*
* E-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

Adiabatic self-heating tests were carried out on five New Zealand coal samples ranging in rank from lignite to high-volatile bituminous. Kinetic parameters of oxidation were obtained from the self-heating curves assuming Arrhenius behaviour. The activation energy E (kJ mol–1) and the pre-exponential factor A (s–1) were determined in the temperature range of 70–140°C. The activation energy exhibited a definite rank relationship with a minimum E of 55 kJ mol–1 occurring at a Suggate rank of ∼6.2 corresponding to subbituminous C. Either side of this rank there was a noticeable increase in the activation energy indicating lower reactivity of the coal. A similar rank trend was also observed in the R70 self-heating rate index values that were taken from the initial portion of the self-heating curve from 40 to 70°C. From these results it is clear that the adiabatic method is capable of providing reliable kinetic parameters of coal oxidation.

Keywords

coalself-heatingadiabatic ovenactivation energy.
Type
Research Article
Information
Mineralogical Magazine , Volume 67 , Issue 4 , August 2003 , pp. 665 - 670
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2003

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

Beamish, B.B., Barakat, M.A. and St. George, J.D. (2000 Adiabatic testing procedures for determining the self-heating propensity of coal and sample ageing effects. Thermochimica Acta, 362, 79—87.CrossRefGoogle Scholar
Beamish, B.B., Barakat, M.A. and St. George, J.D. (2001 Spontaneous-combustion propensity of New Zealand coals under adiabatic conditions. In. Geotechnical and Environmental Issues Related to Coal Mining (Lindsay, P. and Moore, T.A., editors.) Special issue of International Journal of Coal Geology, 45, 217—224.Google Scholar
Carpenter, D.L. and Giddings, D.G. (1964 The initial stages of the oxidation of coal with molecular oxygen I – Effect of time, temperature and coal rank on rate of oxygen consumption. Fuel, 43, 247—266.Google Scholar
Humphreys, D., Rowlands, D. and Cudmore, J.F. (1981 Spontaneous combustion of some Queensland coals. Pp. 1—19 in: Proceedings of the “Ignitions, Explosions and Fires in Coal Mines” Symposium . The AusIMM Illawarra Branch 5.Google Scholar
Jones, J.C. (1997 Environmental and Safety Aspects of Combustion Technolog y . Whittles Publishing, Caithness, Scotland.Google Scholar
Jones, J.C. (2000a) Commentary on the UN test for spontaneous heating of solid substances. Journal of Loss Prevention in the Process Industries , 13, 177—178.CrossRefGoogle Scholar
Jones, J.C. (2000b) A new and more reliable test for the propensity of coals and carbons to spontaneous heating. Journal of Loss Prevention in the Process Industries , 13, 69—71.CrossRefGoogle Scholar
Jones, J.C., Chiz, P.S., Koh, R. and Matthew, J. (1996 Kinetic parameters of oxidation of bituminous coals from heat-release rate measurements. Fuel, 75, 1755—1757.CrossRefGoogle Scholar
Jones, J.C., Henderson, K.P., Littlefair, J. and Rennie, S. (1998 Kinetic parameters of oxidation of coals by heat-release measurement and their relevance to selfheating tests. Fuel, 77, 19—22.CrossRefGoogle Scholar
Kuchta, J.M., Rowe, V.R. and Burgess, D.S. (1980 Spontaneous Combustion Susceptibility of US Coals . US Bureau of Mines Report of Investigations 8474.Google Scholar
Mazumdar, B.K. (1996 On the correlation of moist fuel ratio of coal with its spontaneous combustion temperature. Fuel, 75, 646—648.CrossRefGoogle Scholar
Moreby, R. (1997 Dartbrook coal – Case study. Pp. 39—45 in: Proceedings of the 6th International Mine Ventilation Congress . The Society of Mining, Metallurgy and Exploration Inc., Littleton, USA.Google Scholar
Moxon, N.T. and Richardson, S.B. (1985 Development of a self-heating index for coal. Coal Preparation, 2, 91—105.CrossRefGoogle Scholar
Nugroho, Y.S., McIntosh, A.C. and Gibbs, B.M. (2000 Low-temperature oxidation of single and blended coals. Fuel, 79, 1951—1961.CrossRefGoogle Scholar
Ren, T.X., Edwards, J.S. and Clarke, D. (1999 Adiabatic oxidation study on the propensity of pulverised coals to spontaneous combustion. Fuel, 78, 1611—1620.CrossRefGoogle Scholar
Smith, A.C. and Lazzara, C.P. (1987 Spontaneous Combustion Studies of US Coals . US Bureau of Mines Report of Investigations 9079.Google Scholar
Suggate, R.P. (2000 The Rank (Sr) scale: its basis and its applicability as a maturity index for all coals. New Zealand Journal of Geology and Geophysics, 43, 521—553.CrossRefGoogle Scholar
Sujanti, W., Zhang, D-K. and Chen, X.D. (1999 Lowtemperature oxidation of coal studied using wiremesh reactors with both steady-state and transient methods. Combustion and Flame, 117, 646—651.CrossRefGoogle Scholar
Unal, S., Wood, D.G. and Harris, I.J. (1991 Effects of drying methods on the low temperature reactivity of Victorian brown coal to oxygen. Fuel, 71, 183—192.CrossRefGoogle Scholar
Walters, A.D. (1996 Joseph Conrad and the spontaneous combustion of coal Part 1. Coal Preparation, 17, 147—165.CrossRefGoogle Scholar