An experimental apparatus was developed to measure the thermal properties of coal in order to determine the heats of reactions during devolatilization. Samples were continuously heated from room temperature to 1000 °C at a constant heating rate. Measuring the temperature changes at two selected locations within the sample allowed the calculation of the apparent specific heat and thermal conductivity by employing an inverse numerical technique to solve the heat conduction equation. Five major reaction regions of coal devolatilization were detected: dehydration, transition, resolidification, secondary reactions and contraction reactions. The most complex region was the exothermic resolidification reaction, where coking coals exhibited significant differences from the thermal coals due to higher plasticity. Small endothermic reaction related to tar vaporization also appeared in this region, becoming stronger at higher heating rates. The exothermic contraction reactions ranging between 140 and 250 MJ/m3 appeared above 600 °C as a result of the dehydrogenation and reformation of stronger C-C bonds. The effects of the heating rate within the range of 5°C/min to 100 °C/min were also examined, showing a shift of the reaction peaks to higher temperatures at increased heating rates. The thermal conductivity and diffusivity were almost constant until the decomposition point, rapidly increasing at higher temperatures.
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P.A. Kalson and D.E. Briggs: Proc. of Coal and Coke Series, 28th Canadian Chemical Engineering Conf., Nova Scotia, Oct. 22–25, 1978, Canadian Society of Chemical Engineers, pp. 88–106.
A.T. Ordabaeva, B.T. Ermagambetov, B.K. Kasenov, and E.S. Mustafa: Khimiya Tverdogo Topliva, 1995, vol. 29, pp. 44–46.
J.E. Callanan and K.M. McDermott: Preprints, Fuel Chemistry Division, American Chemical Society, 1987, vol. 32, pp. 237–42.
L.L. Isaacs and E. Tsafantakis: Preprints, Fuel Chemistry Division, American Chemical Society, 1987, vol. 32, pp. 243–49.
E. Melchior and H. Luther: Fuel, 1982, vol. 61, pp. 1071–79.
E.I. Vargha-Butler, M.R. Soulard, H.A. Hamza, and A.W. Neumann: Fuel, 1982, vol. 61, pp. 437–42.
P.N. Nikolaev, N.I. Kozlova, V.A. Kalinkina, and A.A. Stepanchikov: Coke Chem., 1961, vol. 3, pp. 12–14.
A.A. Agroskin and E.I. Goncharov: Coke Chem., 1965, vol. 11, pp. 16–20.
A.A. Agroskin, E.I. Goncharov, and N.S. Gryaznov: Coke Chem., 1972, vol. 9, pp. 3–5.
V.F. Goroshkin, V.V. Oshovskii, and V.I. Saranchuk: Khimiya Tverdogo Topliva, 1997, vol. 5, pp. 80–85.
W.F. Hemminger and S.M. Sarge: J. Thermal Analysis, 1991, vol. 37, pp. 1455–77.
V.V. Hathi and C.M. Sliepcevich: Research Project 368–1, Electric Power Research Institute, Palo Alto, CA, Aug. 1977.
L. Strezov and J. Herbertson: Iron Steel Inst. Jpn. Int., 1998, vol. 38, pp. 959–66.
V. Strezov, J. Lucas, S.R. Osborn, and L. Strezov: Proc. 17th Annual Int. Pittsburgh Coal Conf., Pittsburgh, PA, Oct. 11–15, 1999, University of Pittsburgh, pp. 3–5.
Suhas V. Patankar: Numerical Heat Transfer and Fluid Flow, Hemisphere Publishing Co., New York, NY, 1980, pp. 52–54.
A. Blažek: Thermal Analysis, Van Nostrand Reinhold Co. Ltd., London, 1973, pp. 168–73.
A.A. Agroskin, E.I. Goncharov, L.A. Makeev, and V.P. Yakunin: Coke Chem., 1970, vol. 5, pp. 7–11.
Y. Yun and E.M. Suuberg: Fuel, 1993, vol. 72, pp. 1245–54.
H.D. Glass: Fuel, 1955, vol. 34, pp. 253–68.
D.B. Anthony and J.B. Howard: AIChE J., 1976, vol. 22, pp. 625–56.
S. Badzioch: BCURA Monthly Bull., 1960, vol. 24, pp. 485–519.
This article is based on a presentation made in the “Geoffrey Belton Memorial Symposium,” held in January 2000, in Sydney, Australia, under the joint sponsorship of ISS and TMS.
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Strezov, V., Lucas, J.A. & Strezov, L. Quantifying the heats of coal devolatilization. Metall Mater Trans B 31, 1125–1131 (2000). https://doi.org/10.1007/s11663-000-0088-x
- Material Transaction
- Coal Sample
- Endothermic Reaction
- High Heating Rate
- Coke Coal