CFD-DEM investigation of fluid and particle motion behaviors in initial stage of spiral separation process at low solids concentration

Abstract

ABSTRACT The evolution law of fluid and solid motion in the initial stage of spiral separation process is critical for mineral particle separation. The current research intends to investigate the fluid and particle motion behaviors in the initial stage of a spiral separation process using a CFD-DEM approach. The results show that the motion behaviors of fluids and particles in the initial stage of spiral separation process could be separated into three states: the development state, the transition state, and the relatively stable state. In the development state, water flows outward with a rapid change of velocity and film thickness. Meanwhile, fluid forced particles to move outward rapidly with no obvious trajectory difference. In the transition state, a collision between the slurry and the outer trough sidewall happens with changing the moving direction of fluids and particles. Following the collision, the flow field distribution tends to be relatively constant, and the light particles progressively migrate to the spiral trough’s outer edge, while heavy particles gradually move to the spiral trough’s inner edge.