Preparation and coking properties of coal maceral concentrates

The concentrates with different maceral contents were obtained from Kailuan coking coals with different coal ranks (Ro,ran‾ varying from 0.88% to 1.73%) by float–sink separation in lab. Then these concentrates were characterized by proximate analysis, ultimate analysis, petrography analysis and coking index determination. The results show that the vitrinite is characterized as nature of lower carbon content, higher hydrogen content, higher volatile matter and stronger caking property compared to inertinite. The relationships between variation rate of volatile matter and maximum volatile matter and coal ranks are identified, and a linear model is developed for fast determination of the maceral contents. Compared to inertinite-rich concentrate, the blending ratio of vitrinite-rich concentrate is increased by 13%, which is considered to be a potential technique based on maceral separation for expanding the coking coal resources.