Laboratory-scale validation of a DEM model of a toothed double-roll crusher and numerical studies

A discrete element method (DEM) model of the crushing process of a toothed double-roll crusher (TDRC) is established using the bonded particle model. DEM results and experimental data are compared quantitatively and a relatively good agreement is observed. The effects of rotation speed and structure of crushing rolls on the performance of TDRC are investigated numerically. The results show that when the rolls' speed is relatively high, the nipping condition would be improved, and more cracks could be created to release the increasing strain energy, generating more fractions of small sizes in the products. But, when rolls' speed exceeds 150 rpm, the crushing performance would not be significantly improved. A reasonable working gap and better nipping behaviour are obtained using the spiral-tooth-roll or the staggered-tooth-roll. The validated DEM model could be applied to gain a fundamental understanding of the crushing mechanisms of TDRC.