FCC Regenerator Design and Improvement Using CFD and Kinetic Modeling Tools

Simulation and modeling have become practical diagnostic and predictive tools for large-scale industrial processes and equipment, allowing industrial scientists and engineers to perform “numerical experiments” during different stages of research, development and engineering design.  For example, regeneration of catalysts in the Fluid Catalytic Cracking (FCC) process in different flow regimes can be simulated using a detailed CFD model combined with the simplified reaction kinetics. Results from such a model can help make informed decisions on the design and operating conditions for better process performance, improved energy efficiency and increased operating sustainability.

This presentation gives a brief overview of different approaches to gas-particle CFD as they apply to different FCC regenerator configurations. Flow patterns inside these vessels directly affect their performance and efficiency (of carbon burn and oxygen use) and serve as a qualitative guide to regenerator design improvement. “Numerical tracer” studies can provide a quantitative demonstration of the differences in residence time distributions of both catalyst and gas phase in different regenerator types. Moments of residence time distributions allow one to build ideal reactor networks to simulate the regenerator in conjunction with coke burn kinetics. Such a model shows the differences in coke combustion patterns inside the regenerator, demonstrates the effect of hardware upgrades on the regenerator performance, and ultimately serves as a design tool to assist process and equipment improvement efforts at Honeywell UOP.