THEORETICAL KINETIC-MODEL FOR PARTICULATES DISINTEGRATION PROCESSES THAT RESULT IN BIMODAL SIZE DISTRIBUTIONS

Disintegration is described in terms of a breakage matrix, mass balance on the various size fractions, and expressions that relate the breakage frequency, and thus its rate, to the fraction's size. The main differences between the described and previously published models of this kind are that a large particle from which fines have been detached is allowed to remain, at least temporarily, in its original size slot, and that the breakage frequency of the particle population is described by a bimodal beta-distribution. The advantage of these modifications is a more consistent and realistic account of disintegration in general and erosion-dominated processes in particular. The model capabilities are demonstrated in computer-simulated size distributions during disintegration processes dominated by shattering and erosion, and its usefulness is shown in the comparison of the behavior of agglomerated and freeze-dried instant coffees undergoing mechanical attrition.