CFD simulation of a cement precalciner with agglomerate-based drag modeling

Cement raw meal particles are typical Geldart Group C particles. Due to strong van der Waals forces, the particles are cohesive, tending to form agglomerates. These agglomerates significantly influence the flow, dispersion, heat transfer and calcination of raw meal particles inside cement precalciners. Without considering the agglomeration effects of fine particles, computational fluid dynamics (CFD) simulation of precalciners may fail to accurately predict the flow and dispersion behavior. This paper presents an agglomerate-based drag model by integrating an equilibrium agglomerate size based on energy balance. The new drag is integrated into CFD and validated by simulating a pilot-scale precalciner, showing good agreement with the experimental data.