Computational fluid dynamics simulation of multiphase flow in packed sieve tray of distillation column

Computational fluid dynamic models (CFD) have been used for the description of hydraulic characteristics of packed sieve tray (PST). PST is a conventional sieve tray combined with a slice thickness of packing on the tray deck. Eulerian-Eulerian framework has been used to solve the equations of both liquid and gas phases assumed as two interpenetrating phases. A commercial scaled sieve tray has been simulated based on a three-dimensional unsteady state model. Comparison with experimental data proves good agreement for the simulation results under the studied conditions. Effects of the packing on the liquid velocity distribution, clear liquid height and vertical liquid volume fraction distribution have been investigated. The simulation results show that 3.08 cm of packing thickness could increase the clear liquid height up to 17 percent and froth height up to 10 percent as well as promoting froth density by 6 percent with the only drawback of increasing wet pressure drop up to 16 percent in froth regime