Micro-macro deformation and breakage behaviour of spherical granules
Compression and impact tests have been used to study the deformation and breakage behaviour of spherical granules (γ-Al2O3, zeolites 13X and 4A, sodium benzoate). The elastic compression behaviour of granules is described by means of force-displacement curves and by application of Hertz' contact theory. An elastic-plastic contact model is proposed to describe the deformation behaviour of elastic-plastic granules. The breakage probability is determined by using particle size distributions after the impacts at different velocities and described by a modified Weibull distribution. DEM is applied to analyse the dynamics and mechanisms of microscopic breakage behaviour of the experimentally investigated zeolite granules. The arrangement of the primary particles inside a granule, their coordination number and binder strength have been varied to obtain the breakage probability depending on the impact velocity. © Springer Berlin Heidelberg 2008.