Comparing particle breakage in an uniaxial confined compression test to single particle crush tests—model and experimental results

Abstract

The correlation between single particle breakage parameters and the behavior of particulate beds under compression is a subject that has attracted much interest in the field of particulate solids. This knowledge can assist in simplifying the design of various units for handling and conveying of particulate solids and can be used in computer simulations (DEM) to shorten the computational time. In addition, it is convenient to compress a particulate bed in order to obtain the single particle strength distribution. The current work deals with the development of a mathematical model, correlating the ratio of broken particles in a confined bed compression to single particle strength. The model is based on Jansenn's axial-stress model for a particulate bed, single particle strength distribution and force distribution in a granular media. The developed model not only allows us to predict the ratio of broken particles during uniaxial compression but also allows us to determinate the single particle strength distribution by conducting two uniaxial confined compression tests. Narrow fractions of GNP, zirconium and sodium chloride (NaCl) in the size range of 2–5mm were tested using two rigid cylinders of 25mm and 45mm in diameter, with varying compressive forces and bulk heights. The single particle strength parameters were taken from single particle compression tests performed in the laboratory. The developed model shows good agreement with the experimental results within a certain range of the particulate bed geometry and compressive loads.