Prediction of Temperature and Concentration Distributions of Distillation Sieve Trays by CFD

Mahmood-Reza Rahimi; Rahbar Rahimi; Farhad Shahraki; Morteza Zivdar

doi:10.6180/jase.2006.9.3.09

Prediction of Temperature and Concentration Distributions of Distillation Sieve Trays by CFD

Mahmood-Reza Rahimi This email address is being protected from spambots. You need JavaScript enabled to view it.¹, Rahbar Rahimi¹, Farhad Shahraki¹ and Morteza Zivdar¹

¹Department of Chemical Engineering, Sistan and Baluchistan University Zahedan 98164, Iran

Received: July 21, 2005
Accepted: October 3, 2005
Publication Date: September 1, 2006

Download Citation: ||https://doi.org/10.6180/jase.2006.9.3.09

ABSTRACT

A three-dimensional two-fluid computational fluid dynamics (CFD) model is developed to predict concentration and temperature distributions on sieve trays of distillation columns and good simulation results are obtained. The dispersed gas phase and continuous liquid phase are modeled in the Eulerian framework as two interpenetrating phases with interphase momentum, heat and mass transfer. Closure models are developed for interphase transfer terms. The tray geometries and operating conditions are based on the experimental works of Dribika and Biddulph (AIChE. J., 32, 1864, 1986) and Yanagi and Sakata (Ind. Eng. Chem. Process. Des. Dev., 21, 712, 1982). The computational domain is considered to be equal to tray spacing. The main objective of this study has been to find the extent to which CFD can be used as a prediction tool for real behavior, and concentration and temperature distributions of sieve trays. The simulation results are shown that CFD is a powerful tool in tray design, analysis and trouble shooting, and can be considered as a new approach for efficiency calculations.

Keywords: Computational Fluid Dynamics, Concentration Distribution, Temperature Distribution, Distillation, Sieve Tray

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