Gasification and combustion kinetics of a high-ash-fusion-temperature coal using thermogravimetric analysis

The gasification/combustion kinetics of a typical Chinese high-ash-fusion-temperature (AFT) coal char, Huainan (HN) coal char, are analyzed using a thermogravimetric analyzer in this paper. The carbon conversion rate and the gasification/combustion reaction rate characteristics of HN coal char are studied. The initial gasification/combustion reaction rates are also analyzed in this paper. Results show that at 1300 °C, the gasification and combustion processes are changed from the chemical reaction control zone to the pore diffusion control zone. Thus, 1300 °C is recommended as the gasification temperature of the non-slagging EFGs system using high-AFT HN coal. Based on the isothermal method, a complementary method of iso-conversional and model based is used to analyze the gasification and combustion kinetics of HN coal char. The gasification/combustion reaction order m and activation energy E of HN coal char are obtained by iso-conversional method. The kinetic model equation f(α) is obtained based on a modified master plot method. The kinetic exponent n and the pre-exponential factor k0 are obtained by model-based method. The results of this work provide the useful data for designing the non-slagging EFGs using high-AFT coals.