Prediction of the evolution characteristics of volatile matter over semi-coke during the pyrolysis of coking coals

The behavior of the coal was investigated in order to estimate the kinetics of the devolatilization, owing to the fact that combustion and gasification were strongly dependent on this step. The purpose of this work was to advocate the mathematical model supported by the parameters obtained from the thermogravimetric analyzer and pot apparatus experimental data. The thermal decomposition of coal follows a distributed activation energy model, which describes the kinetics of volatile matter release as a set of independent, parallel first-order reactions resulting from the coal ultimate analysis. The coke yield was calculated using the mass balance method, which develops the correlation for changes in the composition and mass of the solid residue. The present work develops a numerical code to solve the equations for standardized volatile coals under constant heating rate conditions and calculates the yields, composition of species, semi-coke, and mean relative atomic mass in the charge.