Thermal degradation behaviors and kinetics of biomass tar

The thermal degradation behaviors and kinetics of tar, which was gained from straw gasification, were studied at different heating rates (10K/min, 20K/min, 30K/min) under nitrogen atmosphere by thermogravimetric (TG) coupled with Fourier transform infrared spectrometer (FTIR). TG-DTG curves and the corresponding infrared spectrometers were analyzed. The model of pyrolysis kinetics for tar was established and the kinetics parameters of tar were also calculated. The results indicate that the pyrolysis of tar contains two stages, the evaporation stage and the decomposition stage. And both the stages can be expressed by first-order reaction. According to the infrared spectrometers, the pyrolysis products are mainly composed of water, CH4, CO2, CO, alkanes, alkenes, alcohols and esters. The physical and chemical processes of products during tar pyrolysis were analyzed in this paper. Theoretical guidelines for biomass tar pyrolysis are provided based on the insight gained from the experimental results. (C) 2014 The Authors. Published by Elsevier Ltd.