Simulation of the movement of beads by the DEM with respect to the wet grinding process

This work has shown a method for simulating the motion of beads in a bead mill based on the discrete element method (DEM) under wet grinding of a gibbsite powder, in correlation with the experimental work. The beads' motion was simulated under a wet condition and compared with the real motion observed and recorded by a video camera. At the base of the simulation the specific impact energy of beads was calculated. In the experiment, the gibbsite powder, suspended in water at 5.0 wt %, was subjected to grinding by the bead mill at different operating conditions. Particle-size distribution of the product was measured and the grinding rate constant of the sample was determined as a change in the mean particle size of the ground product with time. Then, the specific impact energy was correlated with the grinding rate constant determined experimentally. It was found that good correlation between the two was achieved and by the proposed method the particle size reduction of the sample can be predicted. (c) 2006 American Institute of Chemical Engineers.