Analysis of the self-similarity of single particle impact breakage distributions of cement clinker particles

Abstract

This study analysis how the impact breakage pattern changes at different specific comminution energy levels. Impact breakage patterns of two different cement clinker samples were investigated by plotting size-normalized distribution curves. These curves were obtained by normalizing the breakage product particle size distributions according to the median size (d50) of the distributions. Drop-weight test technique was used to determine impact breakage distributions of particles in different size fractions. Normalized size distributions indicated that, breakage pattern varies with particle size and impact energy level. Breakage product size distributions fall into the same pattern above an energy level of 1kWh/t which indicated a self-similar distribution. Breakage distributions became non-normalizable below this energy level. Probable variations in clinker microstructure, mineralogical and chemical composition on the particle size basis could be the factors for the observed deviations from the self-similarity. Energy levels which provided selfsimilar breakage distributions (the same proportional size reduction) are proposed to estimate breakage functions for the modelling of comminution equipments in which impact mechanism is used.