ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Investigation of open hole area effects on the air dynamic pressure, Froude number, and hydraulics of distillation trays using CFD

Sepideh Roshdi, Norollah Kasiri, Javad Ivakpour, and Seyed Hassan Hashemabadi

Chemical Engineering Department, Faculty of Engineering, Urmia University, Urmia, Iran

E-mail: s.roshdi@urmia.ac.ir

Received: 17 August 2022  Accepted: 4 December 2022

Abstract:

Despite the significant effect of open hole area (OHA) on the distillation tray performance, no numerical study exists to investigate this parameter effect profoundly until now. In the present study, OHA effects on the hydraulics, air dynamic pressure, and Froude (Fr) number have been numerically investigated in commercial-scale sieve trays. To do so, three sieve trays with OHAs of 5, 8, and 14 percent have been studied. In the first step, simulations have been carried out to find the OHA-dependent drag coefficient, and then, validation has been performed using published experimental data and correlations. Simulation results showed that, when the OHA increases from 5 to 14%, the average froth density, clear liquid height, and wet pressure drop increase by 20, 10, and 15%, respectively, while the average froth height reduces by 10% in different gas and liquid flow rates. The efficiency and entrainment values of three tray types have been qualitatively compared using Fr number and air dynamic pressure values, respectively, predicting the smallest value in the tray with 14% OHA. This study's results show that with pure hydrodynamic analysis, it is qualitatively possible to study the geometrical change effects on entrainment and efficiency with air dynamic pressure and Fr number, respectively.

Keywords: CFD; Open hole area (OHA); Sieve tray; Hydraulic; Distillation column

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-022-02623-0

Chemical Papers 77 (4) 2201–2217 (2023)