Effect of mineral matter on the reactivity of lignite chars

In this study, the effect of mineral matter on the combustion reactivity of chars produced from 25 lignite samples originating from various parts of T urkey was investigated. Char samples were produced from both original and d emineralized lignites. Non-isothermal thermogravimetry has been used to det ermine the combustion reactivity of the samples. The combustion activation energies were calculated by the Coats-Redfern and Zsako methods from their TG data. Burning profiles of the original and demineralized lignite chars w ere also compared and discussed. The relationship between the carbon conten ts of the parent lignites and the conversions of their chars at 1273 K was studied as well. It was observed that the mineral species showed an importa nt effect on the combustion reactivity of the char samples. (C) 2000 Elsevi er Science Ltd. All rights reserved.