Development of a Two-Fluid Hydrodynamic Model for a Riser Reactor

Abstract

ANSYS Fluent is used to examine the mixing of catalyst zeolite particles with petroleum feedstock and water vapor in a fluid catalytic cracking (FCC) riser. A two-fluid model is developed for tracking catalyst particles and gas mixture in a riser, modeling the granular and gaseous phases as two interpenetrating continua. The hydrodynamic flows are analyzed with the aim to single out the principal physical effects that determine the distribution of particles. The results are compared with a study that is based on a non-isothermal reactive model. It is demonstrated that the simplistic purely hydrodynamic model generates similar flow fields. The developed model is valuable for improvements of modern FCC risers. The model is applied for understanding the hydrodynamics of an S-200 KT-1/1 industrial unit.