SIMULATION OF BALL CHARGE AND LINEAR WEAR

Ball mills used in the mineral processing industry grind input ore int o finer output. However, during this grinding process, ball mill eleme nt wear affects grinding performance. In this article, wear models are developed in order to determine how a ball charge size distribution a nd liner profiles change as a result of wear. Specifically, it was pos sible to model and then to simulate ball charge and liner wear, two fa ctors that determine ball mill non-stationary behaviour, using results from a ball charge motion model. The ball charge wear model incorpora tes adhesive and abrasive wear as a function of energy dissipated in c rushing, tumbling and grinding zones of the charge motion profile. The liner wear model incorporates abrasive wear with centrifugal and grav itational forces acting on mill liners. Simulation results shows how a ball size distribution evolves in time as well as how two different l iner profiles change over time. These results allow for further work i n ball mill optimization as a function of this non-stationary mill beh aviour.