Observations on the Smith-Glasser index for self-heating of bituminous coal

Self-heating of coal depends partly on intrinsic, coal-related factors. This article aims to discuss the Smith–Glasser index as a potential indicator of the self-heating propensity of a large set of bituminous coals with similar heating value but different origins. For this purpose, recorded properties and experience were reviewed for 7.5 million tonnes of coal delivered to the same power plant operator. The results suggest that the propensity to self-heat can be conveniently indicated by Smith–Glasser index that only involves routinely measured moisture and volatile contents of coal. The results appear consistent with the observed incidences of self-heating in storage.