Thermal-Gravimetry Study of Coal Char Combustion Model

The combustion performances of two kinds of coal chars were studied by using thermal gravitmetry in different oxygen concentrations (100%,30%,20% and 7% O_2 respectively,the rest is argon).Low sample masses were employed to ensure an approximate kinetic regime.After analyzing three combustion models that were used widely and the reasons of the change of the char particle surface-volume during the process of char combustion,it was found that dealing with the change of surface-volume of char particle during the combustion process was an important factor in a combustion model.By comparing the simulation with the experiment result,the model can well simulate the process of combustion.It was a useful method to get the kinetics of the coal char and the trend of combustion in different oxygen concentrations.