The relevance of thermal annealing to the evolution of coal char gasification reactivity

The present work is focused on the influence of the severity of heat treatment of coals during pyrolysis and/or early stages of carbon oxidation on the reactivity of the resulting char towards further gasification. Thermogravimetric analysis has been directed to characterize the reactivity of heat treated samples of a bituminous coal in atmospheres containing different carbon dioxide partial pressures. Carbonization was carried out at different temperatures and for different times prior to thermogravimetric analysis. Parallel microstructural characterization of the samples was accomplished by XRD analysis of untreated coal and heat treated char.