Flotation of Low Volatile Coking Coal Fines

Abstract

Low volatile coking (LVC) coal reserves have become the key for sustaining the coking coal production in India. Because of high ash content and difficult washability characteristics coking coal in India is usually cleaned at 16-18% ash content. To obtain a reasonable yield at this ash level, LVC coal needs to be crushed to less than at least 13 mm before cleaning. LVC coal when crushed to -13 mm, depending on HGI and crushers used fines (-0.5 mm) could constitute 15-25% of the crushed coal. Limited study has so far been done on flotation characteristics of LVC coal fines, though flotation is the only method used in India to clean the coking coal fines. The work presented here after discusses the difficulties associated with the flotation of LVC coal fines arising out of its petrographic composition, complicated liberation characteristics, collector dependency, etc.