Kinetics of coal char gasification with CO2 Random pore model

The gasification of Beisu, Shenfu, Xinzhou and Luan coal chars with CO2 at 970°C-1165°C was studied by the isothermal thermogravimetric analysis (TGA) under the condition of chemical reaction control. The effects of coal types, temperature and ash content in coal on the char gasification with CO2 were examined. The random pore model, the unreacted shrinking core reaction model and the integrated model were tested by the experimental data respectively. The results show that the random pore model is the best to fit the experiment data among three kinetic models, which has a correlation coefficients of 0.99 both at 1066°C and 1165°C. The kinetic parameters (E, k0, A0, Ψ) are obtained. A0 is bigger when the gasification temperature is higher, Ψ as the initial pore structure parameter is affected by the change of pore structure at different pyrolysis temperatures. It becomes smaller when the gasification temperature increases.