Commenced in January 2007
Paper Count: 32586
Countercurrent Flow Simulation of Gas-Solid System in a Purge Column Using Computational Fluid Dynamics Techniques
Authors: T. J. Jamaleddine
Abstract:Purge columns or degasser vessels are widely used in the polyolefin process for removing trapped hydrocarbons and in-excess catalyst residues from the polymer particles. A uniform distribution of purged gases coupled with a plug-flow characteristic inside the column system is desirable to obtain optimum desorption characteristics of trapped hydrocarbon and catalyst residues. Computational Fluid Dynamics (CFD) approach is a promising tool for design optimization of these vessels. The success of this approach is profoundly dependent on the solution strategy and the choice of geometrical layout at the vessel outlet. Filling the column with solids and initially solving for the solids flow minimized numerical diffusion substantially. Adopting a cylindrical configuration at the vessel outlet resulted in less numerical instability and resembled the hydrodynamics flow of solids in the hopper segment reasonably well.
Digital Object Identifier (DOI): doi.org/10.6084/m9.figshare.12488960Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 561
 A. Buchelli, J. Golden and D. Beran, “Determination of polyolefins powder flow characteristics in a purge column during product transitions”, Ind. Eng. Chem. Res., vol. 46, pp. 8120-8129, 2007.
 W.B. Brod and B.J. Garner, “Method for treating resin in a purge vessel,” U.S. Patent 4 758 654, July 19, 1998.
 R.S. Eisinger, B.S. Holden and T.C. Frank, “Apparatus and methods for separating volatiles from particulates,” U.S. Patent Application 0311884 A1, December 13, 2012.
 D. Gunn, “Transfer of heat or mass to particles in fixed and fluidized beds,” J. Heat & Mass Trans., vol. 24, no. 4, pp. 467 - 476, 1952.
 M. Syamlal, W. Rogers and T.J. O’Brien, ANSYS Fluent Theory Guide.
 C.K.K. Lun, S.B. Savage, D.J. Jeffrey and N. Chepurniy, “Kinetic theories for granular flow-inelastic particles in Couette-flow and slightly inelastic particles in a general flow field,” J. Fluid Mech., vol. 140, pp. 223, 1984.
 D. Gidaspow, R. Bezburuah and J. Ding, “Hydrodynamics of circulating fluidized beds: kinetic theory approach”, Fluidization VII, Proceedings of the 7th Engineering Foundation Conference on Fluidization, pp. 75-82, 1992.