Simulation of a Large-Scale FCC Riser Using a Combination of MP-PIC and Four-Lump Oil-Cracking Kinetic Models

Fluidized catalytic cracking (FCC) is the most used process for converting heavy oil into more valuable fuels and chemical products such as gasoline and propylene. A three-dimensional reactive gas particle CFD model was built to study the hydrodynamics, heat transfer, and cracking reaction behaviors within an industrial FCC riser reactor. The multiphase particle-in-cell methodology (MP-PIC) was used to simulate the riser hydrodynamics. A four-lump kinetic model was selected to represent the cracking reaction network in the CFD model. Hydrodynamics, heat, and cracking reactions interplay was discussed. The numerical results of this investigation show a good agreement with the process real data on the yield distribution. The effects of injection (nozzle angle, position, and direction) as well as the riser operating pressure on the yield distribution were quantified and discussed. The methodology employed and the results obtained should serve as guidelines for possible process re-design and optimization.