CFD modeling and industrial evaluation of a cyclone cascade for HDPE catalyst production

A new approach is proposed to evaluate various designs for gas-solid cyclone separators. This approach uses single-phase flow simulation results to find a quantitative measure of flow symmetry in a given cyclone. Flow symmetry is computed by averaging imbalances of non-axial velocities throughout the cyclone. Using this approach, two standard design methods, namely Shepherd and Stairmand design methods, are evaluated and the cyclone with a more symmetric flow pattern is chosen as a starting point for further design improvements by reducing the diameter of its vortex finder. Two-phase computational fluid dynamics simulations computes 90.2% collection efficiency for the improved design. Computational fluid dynamics simulations reveal using a cascade of four cyclones results in an overall 99.98% collection efficiency. Once installed in the actual industrial setting, the cyclone cascade achieves a 98.56% collection efficiency and a particle size distribution which is in good agreement with those computed using Computational fluid dynamics.