Nonisothermal TGA Study on the Combustion Reaction Kinetics of Biomass

The combustion reaction kinetics of two Chinese straws were investigated by a differential thermal balance , volume fraction of reactive gas was N2: O2 = 80:20 and heating rate was 30degC/min. Reaction of samples were mainly composed volatile and fixed carbon combustion phase, ranges of them were 425 K - 650 K and 650 K - 810 K in round numbers according to TG, DTG and DTA curves. Reaction kinetic parameters were calculated with Coats-Redfern method. Ranges of activation energy in volatile combustion phase were 20 kJ.min^-1 or so, fixed carbon combustion phase were different, they were 145 kJ.min^-1 and 66 kJ.min^-1. Results showed that the order of reaction of volatile combustion phase and fixed carbon combustion phase were zero and second, respectively. The reaction initial temperatures of two samples ranged from 420 K - 460 K and reaction final temperatures ranged from 780 K - 810 K.