Studies on low-temperature pyrolysis characteristics and kinetics of the binder cold-briquetted lignite

In this study, pyrolysis process of the binder cold-briquetted lignite (BCBL) was studied comprehensively. The effects of temperature in the range of 350-650 degrees C, heating rate in the range of 5-20 degrees C/min, the residence time at constant temperature in the range of 30-120 min, pyrolysis atmosphere of H-2, CO, CH4, CO2 and N-2 and the particle size in the range of 0.45-6 mm were investigated. The main generated gas species were quantified by two gas chromatographs: H-2, CO, CO2, CH4 and trace amounts of C2H4 and C2H6. A semi-quantitative method was established to proceed the pyrolysis kinetics fitting by the thermal analysis mass spectrometry (TA MS) signals of pyrolytic products. The kinetic parameters of different gas pyrolysates were calculated by the first-order kinetics. The activation energies for H-2, CO, CO2, CH4, C2H4 and C2H6 were found to be close to the reference results. The results reported in this work may provide a theoretical and technical basis for the BCBL pyrolysis and lignite upgrading technology which may have potential application in fuel utilization. (C) 2015 Energy Institute. Published by Elsevier Ltd. All rights reserved.