(8)Characterization of a Limestone Rock Dust for its Wicking, Dispersion, and Inerting Capabilities

摘要

Rock dust, generally limestone dust, is required to be applied in underground coal mines to prevent propagating coal dust explosions. Rock dust, to function properly, must be dispersible and consist of small enough particles to effectively quench flame propagation. Experimental results indicate that untreated rock dust forms a non-dispersible cake when wetted and dried, and that > 75μm particles do not contribute to inerting when tested with Pittsburgh pulverized coal in NIOSH's 20-L explosion chamber. To further examine the contribution of particle size to caking tendencies, wicking rate, dispersibility, and explosion inerting effectiveness of rock dust, one commercial limestone dust was classified into several size fractions and compared on a relative basis to base rock dust.