THERMAL SCIENCE

International Scientific Journal

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Mladen Ilić

,

Simeon Oka

,

Borislav Grubor

ANALYSIS OF THE DYNAMIC BEHAVIOUR OF A BURNING POROUS CHAR PARTICLE

ABSTRACT
The mathematical model developed describes the dynamic behaviour of a porous char particle during combustion. The model of the char particle involves two exothermic reactions: C + O2 = x:CO + y-CO2 — heterogeneous reaction on the internal and external char particle surfaces, and CO + O = CO2— homogeneous reaction inside the char particle. The temperature and gas concentration fields inside the char particle are defined by partial differential equations of heat and mass conservation. Changes of internal surface area and porosity during combustion are included in the mathematical model. The mathematical model results were compared with experiments done in a laboratory fluidized bed reactor. The comparison showed that the model predictions are in a very good accordance with experiments. The model successively followed combustion regime changes with bed temperature and coal type.
PAPER SUBMITTED: 1998-04-15
PAPER REVISED: 1998-06-30
PAPER ACCEPTED: 1999-07-22
PUBLISHED ONLINE: 2020-09-27
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THERMAL SCIENCE YEAR 1998, VOLUME 2, ISSUE Issue 2, PAGES [61 - 73]
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ANALYSIS OF THE DYNAMIC BEHAVIOUR OF A BURNING POROUS CHAR PARTICLE

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence