Thermogravimetric study of the kinetics and characteristics of the pyrolysis of lignite

For a better understanding of the devolatilization characteristics of lignite, a highly volatile lignite was devolatilized at four different heating rates in a thermogravimetric analyzer in this study. The results showed that the lignite pyrolysis process was strongly affected by the heating rate. As the heating rate increased, the differential thermogravimetry peak shifted toward higher temperature. Based on thermal analysis and kinetic equations, the effects of the heating rate on the pyrolysis characteristics has been studied and the information about the linkage between the activation energy (E), pre-exponential factor (A) and weight loss of each heating rate has been analyzed simultaneously. In the pyrolysis of lignite, the activation energies of the samples were found to increase with decreasing heating rate for each temperature stages.