THERMAL SCIENCE

International Scientific Journal

Mostafa Baghsheikhi

,

Alireza Rahbari

,

Seyed Mehdi Ashrafizadeh

,

Mehdi Bidabadi

THE EFFECT OF FUEL PYROLYSIS ON THE COAL PARTICLE COMBUSTION: AN ANALYTICAL INVESTIGATION

ABSTRACT
The aim of this work is to analytically investigate the symmetrical combustion of an isolated coal particle with the fuel pyrolysis effect. The modelling concept of coal particles is similar to that of the liquid droplet combustion but in the case of coal devolatilization, the particles do not shrink like droplet does due to evaporation of liquid fuel. The rate of devolatilization of volatiles can be calculated using the equation that is similar to Arrhenius equation. This model is based on an assumption of combined quasi-steady and transient behaviour of the process and especially focuses on predicting the variations of temperature profile, radius of pyrolysis and transfer number. It is revealed that the entrance of pyrolysis effect into the governing equations leads to the reduction in the film radius and consequently a reduction in the stand-off ratio and transfer number.
KEYWORDS
Analytical Model, Pyrolysis Effect, coal combustion, Devolatilization Rate
PAPER SUBMITTED: 2014-06-22
PAPER REVISED: 2014-09-18
PAPER ACCEPTED: 2014-10-13
PUBLISHED ONLINE: 2014-11-08
DOI REFERENCE: https://doi.org/10.2298/TSCI140622126B
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2016, VOLUME 20, ISSUE Issue 1, PAGES [279 - 289]
REFERENCES
  1. Aouina, Y., Mass, U., Gutheil, E., Riedel, U., Warantz, J., Mathematical Modeling of Droplet Heating, Vaporization, and Ignition Including Detailed Chemistry, Combustion Sciences and Technology, 173 (2001), 1, pp. 1-23.
  2. Okai, K., Tsue, M., Kono, M., Sato, J., Dietrich, D.L., Williams, F., An Experimental Study of Microgravity Combustion of a Droplet Near a Wall, Combustion and Flame, 133 (2003), 1-2, pp. 169-172.
  3. Dombrovsky, L., Sazhin, S., Absorption of Thermal Radiation in a Semi-Transparent Spherical Droplet: ASimplified Model, International Journal of Heat and Fluid Flow, 24 (2003), 6, pp. 919-927.
  4. Miliauskas, G., Interaction of the Transfer Processes in Semitransparent Liquid Droplets, International Journal of Heat and Mass Transfer, 46 (2003), 21, pp. 4119-4138.
  5. Shaw, B.D., Wei, J.B., Dwyer, H.A., Influence of a Cooled Wall on Droplet Stream Combustion, Combustion Sciences and Technology,176 (2004), 2, pp. 215-235.
  6. Shaw, B.D., Theory of Spherically Symmetrical Droplet Combustion with Gas-Phase Fuel Pyrolysis, Combustion Sciences and Technology,177 (2005), 5-6,pp. 1151-1166.
  7. Tseng, C., Viskanta, R., Effect of Radiation Absorption on Fuel Droplet Evaporation,Combustion Sciences and Technology,177 (2005), 8, pp. 1511-1542.
  8. Atzeler, F., Demoulin, F.X., Lawes, M., Lee, Y., Marquez, N., Burning Rates and Flame Oscillations in Globally Homogeneous Two-Phase Mixtures (Flame Speed Oscillations in Droplet Cloud Flames), Combustion Sciences and Technology,178 (2006), 12, pp. 2177-2198.
  9. Ghassemi, H., Baek, S.W., Khan, Q.S., Experimental Study on Binary Droplet Evaporation at Elevated Pressure and Temperature, Combustion Sciences and Technology,178 (2006), 6, pp. 1031-1053.
  10. Ulzama, S., A Theoretical Analysis of Single Coal Particle Behavior During Spontaneous Devolatilization and Combustion, Ph.D. thesis, University of Magdeburg, Germany, 2007.
  11. Ulloa, C., Gordon, A.L., Garcia, X., Distribution of Activation Energy Model Applied to the Rapid Pyrolysis of Coal Blends, Journal of Analytical and Applied Pyrolysis, 71 (2004), 2, pp. 465-483.
  12. Chern, J.S., Hayhurst, A.N., A Model for the Devolatilization of a Coal Particle Sufficiently Large to Be Controlled by Heat Transfer, Combustion and Flame, 146 (2006), 3, pp. 553-571.
  13. Jiménez, S., Ballester, J., Study of the Evolution of Particle Size Distributions and Its Effects on the Oxidation of Pulver-Ized Coal, Combustion and Flame,151 (2007), 3, pp. 482-494.
  14. Higuera, F.J., Numerical Simulation of the Devolatilization of a Moving Coal Particle, Combustion and Flame,156 (2009), 5, pp. 1023-1034.
  15. Yu, J., Zhang, M., Zhang, J., Experimental and Numerical Investigations on the Interactions of Volatile Flame and Char Combustion of a Coal Particle, Proceedings of the Combustion Institute, 32(2009), 2, pp. 2037-2042.
  16. Sadhukhan, A.K., Gupta, P., Saha, R.K., Modelling of Combustion Characteristics of High Ash Coal Char Particles at High Pressure: Shrinking Reactive Core Model, Fuel,89 (2010), 1,pp. 162-169.
  17. Shah, K.V., Cieplik, M.K., Betrand, C.L., Van De Kamp, W.L., Vuthaluru, H.B., A Kinetic-Empirical Model for Particle Size Distribution Evolution During Pulverised Fuel Combustion, Fuel, 89 (2010), 9, pp. 2438-2447.
  18. Liakos, H.H., Theologos, K.N., Boudouvis, A.G., Markatos, N.C., Pulverized Coal Char Combustion: The Effect of Particle Size on Burner Performance, Applied Thermal Engineering, 18 (1998), 11, pp. 981-989.
  19. Marek, E., Świątkowski, B., Experimental Studies of Single Particle Combustion in Air and Different Oxy-Fuel Atmospheres, Applied Thermal Engineering,66 (2014), 1-2, pp. 35-42.
  20. Kim, R.G., Jeon, C.H., Intrinsic Reaction Kinetics of Coal Char Combustion by Direct Measurement of Ignition Temperature, Applied Thermal Engineering,63 (2014),2, pp. 565-576.
  21. Bidabadi, M., Azimi, M., Rahbari, A., The Effects of Radiation and Particle Size on the Pyrolysis of Biomass Particles, Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 244 (2010), 3, pp. 675-682.
  22. Bidabadi, M., Fereidooni, J., Rahbari, A., Theoretical Model of Flame Propagation Through Dry Biomass Particles in a Fixed Bed, World Applied Sciences Journal, 13 (2011), 3, pp. 531-536.
  23. Rahbari, A., Ebrahiminasab, F., Bidabadi, M., Analytical Model for Predicting the Heat Loss Effect on the Pyrolysis of Biomass Particles, Chinese Journal of Chemical Engineering, 21(2013), 10, pp. 1114-1120.
  24. Bidabadi, M., Rahbari, A., Modeling Combustion of Lycopodium Particles by Considering the Temperature Difference Between the Gas and the Particles, Combustion, Explosion, and Shock Waves, 45 (2009), 3, pp. 278-285.
  25. Bidabadi, M., Rahbari, A., Novel Analytical Model for Predicting the Combustion Characteristics of Premixed Flame Propagation in Lycopodium Dust Particles,Journal of Mechanical Science and Technology,23 (2009), 9, pp. 2417-2423.
  26. Bidabadi, M., Haghiri, A., Rahbari, A., The Effect of Lewis and Damköhler Numbers on the Flame Propagation Through Micro-Organic Dust Particles, International Journal of Thermal Sciences, 49(2010), 3, pp. 534-542.
  27. Bidabadi, M., Shakibi, A., Rahbari, A., The Radiation and Heat Loss Effects on the Premixed Flame Propagation Through Lycopodium Dust Particles, Journal of the Taiwan Institute of Chemical Engineers, 42(2011), 1, 180-185.
  28. Goldberg, P.M., Essenhigh, R.H., Coal Combustion in a Jet-Mix Stirred Reactor, Symposium (International) on Combustion, 17 (1979), 1, pp. 145-154.
  29. Badzich, S., Hawksley, P.G.W., Kinetics of Thermal Decomposition of Pulverized Coal Particles, Industrial and Engineering Chemistry Process Design and Development, 9 (1970), 4, pp. 521-530.
  30. Borman, G.L., Ragland, K.W., Combustion Engineering, McGraw-Hill, New York, USA, 1998.
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The effect of fuel pyrolysis on the coal particle combustion: An analytical investigation

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