Combustion kinetic parameters of thai lignite char

Abstract

Kinetic parameters, the pre‐exponential factor and the activation energy, of two Thai lignite char of different ash contents and electrode carbon have been experimentally determined based on the Semenov's thermal ignition theory adapted to single particle ignition. Combustion rate constants obtained have been comparatively plotted with those from Field's correlation (1969). Results indicated that the reaction rate coefficient for lignite char approaches value estimated from Field's equation at temperature about 850°C.

CO2 gasification characteristics of nascent pyrolyzed particles from coals and oil shale

“…Kinetics analysis methods were used to study the carbon dioxide gasification of nascent oil shale, bitumite, lignite, and the blends of oil shale with other two types of coals. The rate of fuel's conversion, dα / dt , is the linear function of a temperature‐dependent rate constant and function of conversion, which is described as k ( T ) and f ( α ), respectively , where α is the conversion degree, t (s) is experimental time, T (K) is the absolute temperature, k (T) usually described by the Arrhenius equation, where A (s −1 ) is pre‐exponential Arrhenius factor, E (kJ/mol) is the apparent activation energy, R (kJ/mol K) is the universal gas constant.…”

“…Kinetics analysis methods were used to study the carbon dioxide gasification of nascent oil shale, bitumite, Gasification characteristics of fossil fuels S. Li and X. Ma lignite, and the blends of oil shale with other two types of coals. The rate of fuel's conversion, dα/dt, is the linear function of a temperature-dependent rate constant and function of conversion, which is described as k(T) and f(α), respectively [25,26],…”