Quality improvement of heat altered coals: A preliminary feasibility study

Abstract

Magmatic intrusion of coal results in plethora of alterations in both chemical and physical properties. Such alterations affect both organic and inorganic components in coal in addition to surface chemistry modifications. Beneficiation processes largely depends on the surface chemistry of coals. Heat affected coals are challenging to beneficiate owing to their unique surface properties compared to bituminous coals. In our present work, we have successfully beneficiated heat altered coal from Jharia Coalfield, India, with 28% ash content. The proposed beneficiation process combining micronization and oil agglomeration could reduce the ash content to 10%, which is approximately 60% reduction from parent coal. The organic matter recovery has been around 80% for different particle sizes along with enhancement of volatile matter content from 7% in parent coal to nearly 27% in agglomerated clean coal.