Experimental Design of Effect of Grinding Media on Three-Dimensional Morphology of Products Based on Micro-CT

Grinding experiments of coal are designed to study the influence of spherical and cylindrical media on the three-dimensional morphology characteristics of grinding products. Details of experiments consist of coal grinding, screening of grinding produces, non-destructive testing of coarse-grained coal based on high-resolution three-dimensional X-ray microscopic imaging system, and particle segmentation extraction and three-dimensional morphology feature parameter calculation based on the Dragonfly software. For the low rotation rate condition of the ball mill, if the total surface area or total mass of grinding media is the same, breakage rate of the top size particles ground by the grinding ball is higher than that of the cylindrical media. Moreover, the yield of −1 mm fines yielded by the ball is the highest. The grinding effect reduces the volume and surface area of coarse materials. For the three grinding conditions, the steel cylindrical media with the largest surface area has a more significant “grinding and stripping” effect on coal and the highest particle sphericity.