Innovative hydrocyclone inlet designs to reduce erosion-induced wear in mineral dewatering processes

Abstract

The hydrocyclone is a mechanical separation device that is used widely in mineral processing. The solid particles in mineral slurries are separated according to their density, size, and shape by the centrifugal force generated by an induced vortex motion in a cylinder-on-cone vessel. The larger and denser particles move closer to the wall region due to their greater inertia and descend by gravity; a higher concentration suspension is thus collected at the bottom of the hydrocyclone. The cleaned liquid and hydrodynamically smaller particles exit through an overflow outlet at the top of the hydrocyclone. Higher velocities, within limit, generally yield higher collection efficiency. However, higher stream velocities cause severe erosion of the internal wall of hydrocyclones as mineral slurries generally are abrasive. The objective of this study is to use the computational fluid dynamic (CFD) technique to model the turbulent swirling flow and predict regions of significant wear and how they are influenced by design of the inlet ducting. New inlet designs are proposed and investigated numerically for their erosion characteristics, pumping power requirements, and collection efficiency. Successful innovation in hydrocyclone design will lead to reduced maintenance and lower operating energy costs in mineral processing.