Combustion Characteristics and Kinetics of Anthracite Blending with Pine Sawdust

The combustion characteristics and kinetics of anthracite, pine sawdust and their blends were investigated under combustion condition by thermogravimetric analysis, respectively. The fractions of pine sawdust in the blended samples were set to be 30%, 50%, and 80%. The results showed that the ignition and burnout temperatures of pine sawdust were lower and the maximum combustion rate was higher than those of anthracite. With the increase of pine sawdust content, the ignition temperature and burnout temperature of the blends decreased, while the maximum mass loss rate and the combustible index of the blends increased; that is, the comprehensive combustion property became better. The kinetic parameters for the blends combustion under air condition were calculated based on experimental results using Coats-Redfern model. When the pine sawdust content varied in the range of 30%-80%, the combustion processes of these blends could be divided into two stages and the combustion reactions belong to the first-order reaction. The values of apparent activation energy at two individual stages decreased from 68.78 to 47.28 kJ · mol^-1 and from 113.53 to 46.43 kJ · mol^-1, respectively.