Packing density of irregular shape particles: DEM simulations applied to anode-grade coke aggregates

Abstract

Particle packing problem exists in variety of applications such as transportation, packaging, agricultural and pharmaceutical industries. Particles have not always regular shapes and this makes the packing problem more complex. Understanding the packing characteristics and enhancing the packing density of granular systems is of interest for different industries. In the present work, packing density of an irregular shape particulate system is investigated. The approach is applied on anode-grade calcined coke aggregates with the aim of improving the Vibrated Bulk Density (VBD) of the aggregate recipe which is currently used in industry. A three-dimensional imaging technique is coupled with Discrete Element Method (DEM) simulations to model the coke particles. To study the packing of an industrial aggregate recipe, a sample with only the largest fraction of coke particles were created by DEM. Then, the pore size distribution of this sample was obtained. New aggregate recipes were created according to the results of the pore size distribution. Results showed that the modified recipes with even a lower number of size fractions hold higher vibrated bulk densities than the standard industrial sample. The voids tracking method used in this study is an effective tool to study the packing density of granular systems.