The influence of pyrolysis temperature on lignite reaction kinetics and gas devolatilization process

摘要

Pyrolysis is a clean method for lignite utilization, and it is greatly influenced by temperature and heating rate. The reaction mechanism and kinetic model were investigated by means of Differential Thermal-Gravimetric Analyzer and Fourier Transform Infrared spectrometer. It is found that lower heating rate leads to prolonged reaction process and less residue mass, whereas higher heating rate causes more intense reaction rate with different devolatilization gas compositions. In addition, the generations of CO_2 and CO have different functional groups resources and corresponding temperature ranges. The temperature range discrepancies are mainly caused by the organic functional groups diversity, which is produced when chemical bridge bonds between the adjacent structural element molecules crack. Finally the reaction kinetic parameters are given by test datum regression, and the reliable index indicates that the calculation is credible.