Kinetics of thermal pyrolysis of Eucalyptus bark by using thermogravimetric-Fourier transform infrared spectrometry technique

Abstract

In Southern China, the bark residues from Eucalyptus trees are collected and burned to generate electricity. They are prone to self-heating and even spontaneous combustion when stored in large-scale stockpiles. Pyrolysis plays an important role in these processes. In this work, the pyrolysis characteristics of Eucalyptus bark were investigated by using thermogravimetric analysis coupled with Fourier transform infrared spectrometry. The mass loss process of Eucalyptus bark pyrolysis consists of three stages: dehydration, decomposition of organic matters and decomposition of oxalate, lignin and other components. Except the decomposition of minerals, Eucalyptus bark pyrolysis was described by a four pseudo-component reaction scheme and the kinetic parameters were obtained by using the genetic algorithm. The major evolved gas species and their generation temperature ranges during Eucalyptus bark pyrolysis were identified by Fourier transform infrared spectrometry. It was found that the temperature ranges of the evolved gases were consistent with the decomposition temperature ranges of pseudo-cellulose and pseudo-hemicellulose, in particular with that of pseudo-cellulose.