2016 Volume 57 Issue 3 Pages 438-444
Stereological correction, which corrects an overestimation of the degree of liberation of minerals in a two-dimensional measurement, has not been adequately established, despite its importance in the evaluation of not only the crushed product but also the efficiency of comminution and sorting in the mining process. A unique numerical method was conducted using Discrete Element Method in order to investigate the relationship between the two-dimensional information obtained by cross-sectional measurement and three-dimensional practical information. First, spherical particles of a certain-sized dispersion were packed in a sampling cell. Following this, phases with a lognormally distributed volume fraction, which was designated by a median MD and standard deviation SD, were placed between the particles. Finally, the serial cross-sectional information was analyzed in the height direction, and the following fundamental results were obtained: 1) the area fraction of the cross-sectional circles distributed around the practical volumetric fraction and 2) the degree of liberation was overestimated by the two-dimensional cross-sectional measurement. A series of parametric studies was then conducted on the phases using various MD and SD values, and a correlation between the two-dimensionally measured and three-dimensional actual parameters was obtained. In using this correlation, the volumetric distribution of the phase, together with its degree of liberation (which is usually difficult to measure directly), was estimated with parameters obtained by cross-sectional measurement, such as optical microscopy, QEM*SEM, and MLA. This was based on the assumption that all the particles include a single spherical phase with a lognormally distributed volume.