Impact of Particle Size and Bulk Density of Coal on Coking Behavior

Abstract

In the point of view of reducing coke production cost and future resource depletion, it is necessary to produce high-strength coke from low-rank coal.

It is reported that high strength coke can be obtained by pulverizing, compacting, and carbonizing low-rank coal, non-or-slightly-caking coal. In this study, we research the effects of coal size and coal charging density on coke strength and coke density, and discuss the mechanism for the change of coke properties. Coal of 1.0 mm or less to 0.1 mm or less was compacted to 0.8 g/cm³ to 1.1 g/cm³, carbonized at 900°C, and coke strength and coke density were measured.

As a result, it was found that coke strength significantly increased by pulverizing to 0.1 mm or less and increasing the coal charging density. The effects of coal particle size and coal charging density on coke properties are examined. When the grain size of coal becomes finer, swelling is suppressed, and large pores and connecting pores of coke are reduced. As the coal charging density increased, the coke density increased due to the shortening of the distance between coal particles.