Granular Modelling of Gas-Solid Hydrodynamics in Fluid Catalytic Cracking (FCC) Riser Reactors using Commercial Code

摘要

The application of commercial computational fluid dynamics (CFD) usefulness to study the hydrodynamics of gas-solid flow in FCC is a complex phenomenon. The essence of this study is basically on the heat transfer conservation and economies. In order to establish concise and reasonable predictions, a choice of runs for time-average comparison for solid velocities and concentrations to measure fluxes and densities along the riser axes of heat transfer were used. The model structure were carried out successfully and compared with experimental data on a CFB/FCC riser length of 15.1m and 0.10m in diameter. The model incorporates a two-fluid framework with kinetic theory of granular flow (KTGF) to simulate fully developed gas-solid flows in vertical risers. This study presents the simulation of gassolid hydrodynamics and flow behaviour in a riser circulating fluidised bed (CFB) reactor using the Eulerian-Lagrangian two-fluid modelling approach, incorporating a kinetic theory constitutive model for dilute assemblies of FCC particulate solid. The interaction between gas and particles was modelled using particle interphase momentum transfer model with Schiller-Naumann drag model on a proprietary CFD code (ANSYS CFX), using turbulent k- models. The predicted heat transfer coefficients were reasonably compared with published experimental data. The overall flow patterns within the fluidise bed riser were predicted well by the model. The results of this study help in predicting the commercial implications and its economics toward the choice of heat conservation and utilisation in the FCC process systems.