CHARACTERIZATION OF COALS FOR COMBUSTION USING PETROGRAPHIC ANALYSIS - A REVIEW

Petrographic analysis can give useful information about the combustion of pulverized coal. However, the relations between maceral types and reactivity are not simple; for example, not all inertinites are inert, and not all vitrinites are reactive. This is a consequence of the formal definition of macerals and the variations between coals from different parts of the world. The reflectance values of the maceral groups and the associations of the different macerals, determined as microlithotypes, also need to be taken into account. Mineral matter also has an effect on the type of char formed, and the situation is further complicated by the different char characterization schemes in the literature. The main conclusion from this review is that any predictive system needs to take all these factors into account, especially reflectance.