The overall objective of this project was to determine the combustion properties of separated single coal maceral fractions from a rank series of coals and then to try to predict the combustion behaviour of various whole coals on the basis of their maceral compositions and rank. The combustion properties studied were based on the burning profile in a TGA apparatus. The results of this study indicate that most of the reactivity and combustion profile parameters varied significantly with coal rank and that all of the rank trends observed were best defined in the data from the single maceral samples which were more reproducible, more linear, and less variable. The variations in the combustion profiles and reactivities in different macerals from the same sample are of the same order of magnitude as the variations due to rank. It also appears that there are some maceral interactions during combustion and gasification that significantly affect these processes.
Combustion characteristics of coals and macerals: J. C. Crelling et al. Table 3 Results of TGA analysis on whole coal samples Sample description Moisture (%) Chemisorption (%I Ash WI
T2 T3
Max. rate of weight loss