THERMAL SCIENCE
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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.
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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