The effects of inlet diameter and feed particle concentration on hydrocyclone separation performance

Hydrocyclones are widely used as separation and classification equipment in industries such as mining and metallurgy. However, the mechanism and influence factors of the hydrocyclone still need further investigation. This research numerically investigates the influence of the hydrocyclone’s feed particle concentration and inlet diameter on particle separation efficiency. The hydrodynamic behaviour of the gas-liquid-particle mixture inside the hydrocyclone is simulated using a numerical technique that incorporates the Volume of Fluid (VOF) and the Two-Fluid Model (TFM). The numerical method is quantitatively validated against experiments. Numerical simulations with different inlet diameters and feed particle concentrations are performed to study flow field features and separation efficiency. According to the results of computational simulations, it is evident that the inlet diameter and pressure drop, axial velocity, and tangential velocity are positively correlated. Under certain feeding concentration conditions, the increase in inlet diameter significantly decreases the effectiveness of fine particle separation but has minimal influence on coarse particles. In general, the increase in inlet diameter and feed particle concentration leads to a decrease in the separation efficiency of fine particles. Regardless of the inlet diameter, the cut size increases proportionally to the feed concentration, while the separation sharpness shows irregular changes.