Particle dynamics simulation of wet granulation in a rotating drum

TL;DR

This paper uses three-dimensional molecular dynamics simulations to study wet particle granulation in a rotating drum, revealing how material parameters influence growth and erosion dynamics, and paving the way for more realistic granulation models.

Contribution

It introduces a detailed simulation approach that captures particle-scale mechanisms of wet granulation in a rotating drum, highlighting the effects of various material parameters.

Findings

Granule growth follows an exponential time dependence.

Material parameters significantly affect accretion and erosion rates.

The results suggest a basis for realistic granulation modeling.

Abstract

We simulate the granulation process of solid spherical particles in the presence of a viscous liquid in a horizontal rotating drum by using molecular dynamics simulations in three dimensions. The numerical approach accounts for the cohesive and viscous effects of the binding liquid, which is assumed to be transported by wet particles and re-distributed homogeneously between wet particles in contact. We investigate the growth of a single granule introduced into the granular bed and the cumulative numbers of accreted and eroded particles as a function of time for a range of values of material parameters such as mean particle size, size polydispersity, friction coefficient, and liquid viscosity. We find that the granule growth is an exponential function of time, reflecting the decrease of the number of free wet particles. The influence of material parameters on the accretion and erosion rates reveals the nontrivial dynamics of the granulation process. It opens the way to a granulation model based on the realistic determination of particle-scale mechanisms of granulation.