โ Scribed by F. Agus; P.L. Waters
No coin nor oath required. For personal study only.
Coals fed into grinding mills usually contain shaley material which modifies the overall grindability.
The purpose of the work was to find whether it would be possible to predict the grindabiiity of such mixtures from knowledge of the grindabilities of the components. Modified Hardgrove grindability tests on artificial binary mixtures of coal and shale have demonstrated that the rectilinear law of mixtures applies provided that constant-volume feed samples (75 cm31 are used and that measurements are expressed on a volume basis: that is, the volume of -200 mesh ES material produced from each component is proportional to the volumetric fraction of that component in the mixture. Grindabilities of coal/shale mixtures may thus be predicted.
๐ SIMILAR VOLUMES
Analysis of the standard method for measuring Hardgrove grindability indices has led to the conclusion that a valid figure for reproducibility cannot be established without further definition of the calibration process. Ignoring any possible systematic differences between laboratories, and consideri