A relationship between the kinetic parameters of char combustion and the coal's properties

• Published in: Combustion and flame Vol. 109; no. 4; pp. 587 - 598
• Main Authors: Fu, W.B., Zhang, B.L., Zheng, S.M.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01-06-1997; Elsevier Science
• Subjects: Applied sciences; Combustion of solid fuels; Combustion. Flame; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Theoretical studies. Data and constants. Metering; Combustion; Oxidation; Activation energy; Char; Combustion velocity; Coal
• ISSN: 0010-2180; 1556-2921
• DOI: 10.1016/S0010-2180(97)89632-0

It is suggested that the activation energy,
E, for the combustion of a char is independent of the coal's properties and only varies with the temperature of the char particle; also, the frequency factor of char oxidation,
k
o,
ch
, depends on the coal's properties during its burning in air. We have taken
E = 180 kJ/mol as a constant in the oxidation of any coal char burning in air. Based on experiments for different coals, a relationship between
k
o,
ch
and the coal's properties, applicable to any coal char burning in air, is derived. The relationship is different from those proposed previously, i.e., with both
E and
k
o,
ch
varying disorderly with a coal's properties. Now,
k
o,
ch
can easily be predicted from the proximate analysis of the coal. Furthermore, it can be demonstrated that
k
o,
ch
is also related to the burning regime; a quantitative relationship is presented.