Numerical simulation and optimization of an industrial fluid catalytic cracking regenerator

Fluid catalytic cracking (FCC) is one of the most important conversion processes in petroleum refineries. FCC regenerator is a key part of an FCC unit to recover the solid catalyst reactivity by burning off the deposited coke on the catalyst. In this paper, a three-dimensional multi-phase, multi-species reacting flow computational fluid dynamics (CFD) model was established to simulate the flow and the reactions inside an FCC regenerator. The Euler-Euler approach, where the two phases (gas and solid) are considered to be continuous and fully inter-penetrating, is employed. A modified drag force model was applied on the CFD model with appropriate influential cluster diameters of particle grouping phenomenon. The developed CFD model was validated by using plant data. With the validated CFD model, the flow characteristics and the inner-phase and inter-phase reactions were studied. The results showed that the effect of oxygen enrichment on the catalysts recovery efficiency was limited when the oxygen enrichment exceeded 5%. (C) 2016 Elsevier Ltd. All rights reserved.