Study on Combustion Kinetics of Wheat Distiller Grains by Thermogravimetric Analysis

Thermal characteristics of wheat distiller grains were studied by thermogravimetric analysis (TGA) at heating rates of 10, 20, 30 K min(-1) for combustion processes at atmospheric pressure. An oxidative atmosphere (N-2:O-2 = 2.82 in volume ratio) were used to examine the combustion process. The effects of the heating rate have been investigated. The results indicated that the combustion process takes place in four phases, i.e., the drying, the volatile release and combustion, the fixed carbon burning and the formation of ash. It was found that the heating rate was very important factors influencing the biomass combustion. The characteristic temperature for the maximum reaction rate was found to shift toward higher temperature when the heating rate increased. A kinetic analysis was performed to fit TG data by using Coats-Redfern method and some apparent kinetic parameters such as activation energies, pre-exponential factors and reaction orders were derived. These kinetics parameters may help one understand better the thermo-chemical behavior of the wheat distiller grains and design reactors for more efficient thermo-chemical utilization of the distiller grains.