DEVELOPMENT OF A PELLET SCALE MODEL FOR TRICKLE BED REACTOR USING CFD TECHNIQUES

Document Type : Research Paper

Authors

1 Research Institute of Petroleum Industry (RIPI)

2 Computational Fluid Dynamics (CFD) Research Laboratory, School of Chemical Engineering, Iran University of Science and Technology, Tehran, 16846, Iran

Abstract

In this study, a pellet scale model was developed for trickle bed reactor utilizing CFD techniques. Drag coefficients were calculated numerically at different velocities and bulk porosities in the case of single phase flow through the dry bed. The simulation results were then compared with the prediction of Kozeny-Carman (K-C) equation. The results indicated that drag coefficients calculated from the square arrangement of cylindrical particles in the pellet scale model were in good agreement with Kozeny-Carman equation prediction; however, triangular arrangement had over prediction comparing with Kozeny-Carman equation. Afterward, the pellet scale model with square arrangement was developed for fully pre-wetted particles which were enveloped with a liquid film. The VOF model was used to investigate the boundary condition on the surface of the static liquid layer. The results of CFD simulation in various gas velocities indicated that, at the adjacent of the particle walls, the no-slip boundary condition was acceptable. This pellet scale model was also in good agreement with the Kozeny-Carman equation.

Keywords

References

[1] Attou A., Boyer C., Ferschneider G., “Modelling of the Hydrodynamics of the Cocurrent Gas-liquid Trickle Flow through a Trickle-bed Reactor”, Chem. Eng. Science. 1999, 54, 785-802.
[2] Boyer C., Volpi C., Ferschneider G., “Hydrodynamics of Trickle Bed Reactors at High Pressure: Two-phase Flow Model for Pressure Drop and Liquid Holdup, Formulation and Experimental Validation”, Chem. Eng. Science. 2007, 62, 7026-7032.
[3] Lopes R. J. G., Quinta-Ferreira R. M., “Three-Dimensional Numerical Simulation of Pressure Drop and Liquid Holdup for High-pressure Trickle-bed Reactor”, Chem. Eng. Journal. 2008, 145, 112-120.
[4] Bazmi, M., Hashemabadi, S. H., Bayat M., “Modification of Ergun Equation for Application in Trickle Bed Reactors Randomly Packed with Trilobe Particles Using Computational Fluid Dynamics Technique”, Korean J. Chem. Eng. 2011, 28(6), 1340-1346.
[5] Bazmi, M., Hashemabadi, S. H., Bayat, “CFD Simulation and Experimental Study for two-Phase Flow through the Trickle Bed Re-actors, Sock and Dense Loaded by Trilobe Catalysts”, International Communications in Heat and Mass Transfer, 2011. 38, 391-397.
[6] Carbonell R. G., “Multiphase Flow Models in Packed Beds”, Oil & Gas Science and Technology 2000, 55(4) 417-425.
[7] Lakota A., Levec J., Carbonell R. G., “Hydrodynamics of Trickling Flow in Packed Beds: Relative Permeability Concept”, AIChE Journal. 2002, 48(4), 731-738.
[8] Nemec D., Levec J., “Flow through Packed Bed Reactors: 2. Two-phase Concurrent Downflow”, Chem. Eng. Science, 2005, 60, 6958-6970.
[9] IliutaI., Larachi F., “Modeling the Hydrodynamics of Gas-liquid Packed Beds Via Slit Models: Review” .2005, The Brekeley Electronic Press, 3.
[10] IliutaI., Larachi F., Al-Dahhan M. H., “Multiple-zone Model for Partially Wetted Trickle Flow Hydrodynamics”, Chem. Eng. Res. Des. (Trans IChemE part A) 2000, 78, 982-990.
[11] Attou A., Ferschneider G., “A Two-fluid Hydrodynamic Model for the Transition between Trickle and Pulse Flow in a Cocurrent Gas-liquid Packed-bed Reactor”, Chem. Eng. Science. 2000, 55, 491-511.
[12] Attou, A., Ferschneider, G., “A. Two-fluid Model for Flow Regime Transition in Gas-Liquid Trickle-bed Reactors”. Chemical Engineering Science. 1999, 54, 5031-5037.
[13] Gunjal P. R., Kashid M. N., Ranade V. V., Chaudhari R. V., “Hydrodynamics of Trickle-Bed Reactors: Experiments and CFD Modeling”, Ind. Eng. Chem. Res. 2005, 44, 6278-6294.
[14] Lopes R. J. G., Quinta-Ferreira R. M., “Evaluation of Multiphase CFD Models in Gas-liquid Packed-bed Reactors for Water Pollution Abatement”, Chem. Eng. Science, 2010, 65, 291-297.
[15] Souadnia A., Latifi M. A., “Analysis of Two-phase Flow Distribution in Trickle-bed Reactors”, Chem. Eng. Science. 2001, 56, 5977-5985.
[16] Nemec D.,Levec J., “Flowthrough packed bed reactors: 1. Single-phase flow”, Chem. Eng. Science. 2005, (60), 6947–6957.
[17] Trivizadakis M. E., Giakoumakis D., Karabelas A. J., “A Study of Particle Shape and Size Effects on Hydrodynamic Parameters Of Trickle Beds”, Chem. Eng. Science. 2006, 61, 5534–5543.
[18] Lanfrey P. Y., Kuzeljevic Z. V., Dudukovic M.P., “Tortuosity Model for Fixed Beds Randomly Packed with Identical Particles”, Chem. Eng. Science. 2010, 65, 1891-1896.
[19] Hellstrom, J. G., Lundstorm T. S., “Flow through Porous Media at Moderate Reynolds Number”, International Science Colloquium, Modeling for Material Processing. 2006, Riga, June 8-9.
[20] Lopes R. J. G., Quinta-Ferreira R. M., “Numerical Simulation of Trickle-Bed Reactor Hydrodynamics with RANS-Based Models Using a Volume of Fluid Technique”, Ind. Eng. Chem. Res. 2009, 48, 1740-1748,.
[21] Gunjal P. R., Ranade V. V., Chaudhari R. V., “Computational Study of a Single-phase Flow in Packed Beds of Spheres”, AIChE Journal. 2005, 51 (2), 365-378.
[22] Patankar S. V., “Numerical Heat Transfer and Fluid Flow”, Taylor and Francis 1980.
[23] Macdonald I. F., El-Sayed M. S., Mow K., Dulllen F. A. L., “Flow through Porous Media: the Ergun Equation Revisited”, Ind. and Eng. Chem. Fundamentals. 1979, 18, 199-208.
[24] M. Rahman, Karim, Md. M., Alim, Md. A., “Numerical investigation of unsteady flow past a circular cylinder using 2D finite volume method” Journal of Naval Architecture and Marine Engineering. 2007, 4, 27-42.
[25] Haider A., Levenspiel O., “Drag Coefficients and Terminal Velocity of Spherical and Nonspherical Particles”, Powder Techno-logy. 1989, 58, 63-70.

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