Simulating Pressure Distribution in High Pressure Grinding Rolls Using the Discrete Element Method

It has previously been shown that the compressive breakage principle utilized in a HPGR is a highly energy efficient way of reducing the particle size of rock material, minerals and ores. However, there are a number of operational issues known related to the HPGRs. Due to the high forces and local pressures acting upon the roller surface the wear rate is commonly severe contributing to a substantial part of the operational cost. In this paper the roller pressure distribution is investigated using the discrete element method (DEM). In the quest of modelling HPGR machines incorporating all aspects such as machine dynamics and rock breakage, the work will be split into a number of tangible stages. In this initial work a simplified approach will be used to investigate the edge effect and pressure distribution on the rollers using non-breakable particles. Later stages will incorporate breakage models and the complex floating machine dynamics of the HPGR. Results shows that DEM can be used for modelling and simulating HPGR machines giving novel information regarding pressure distribution, edge effect and particle flow characteristics