Estimating breakage of fine ore particles by media in a small ball mill using DEM

Most DEM analyses of ball and stirred mills reported to date have considered only media motion and its interaction with the mill lifter configuration. For SAG mills, a large fraction of the feed material can already be well represented in DEM models. But for other mill types with much finer feed, the number of feed particles has been prohibitive to include them directly in the calculations. The C-MIS code is now sufficiently powerful to allow inclusion of ore particles within a short periodic section of a small pilot (or large lab) scale mill. This provides the opportunity to better understand the effect of media on the interstitial bed of powder and of the powder on the media. In this paper, the complete pilot mill was first simulated with media only included. A truncated size distribution was then used to represent ore particles in a periodic simulation of about one tenth of the mill length. The results allowed for analysis of the effect of rock on the overall flow, and the influence of the fl ow and collisional environment on the fine ore particles. The normal, shear and total energy consumptions were also analysed for different powder fi ll levels