DISCRETE ELEMENT MODELLING OF BALL MILL.

Abstract

The prediction of product distribution of ball mill units in view of modifications in the operating conditions and change in feed distribution poses a great challenge in mineral processing plant. This generates an increasing demand to develop detailed process model for ball mill, as a tool; to test the flexibility of it to process a wider range of feed materials. Discrete element model developed from axial dispersion model using finite difference method to find the product distribution of the very small particles of product. In present study, discrete element modelling of ball mill is presented. The discrete element model has been studied to predict the effects of various pertinent parameters like residence time, selection function parameters, breakage distribution parameter and axial mixing effect. This developed discrete element model is simulate using MATLAB 7.0 to predict the changes in oversize particle distribution of products by varying pertinent operating parameters such as residence time, axial mixing, selection function parameters and breakage distribution function parameter. In the present work, two case studies are undertaken for the study of discrete element model. The results obtained from the present analysis compared well with the continuous data. The present model is able to predict the experimental data within error band of -12% to +5 % for case study-I and -+8 % to -22 % for case study-II.