Multi-Scale Model of Radial Reactor for Xylene Isomerization Integrating Kinetics and CFD Validated by Long-Term Data

Radial reactors are widely adopted in xylene isomerization due to their low pressure drop and high throughput, though their extended operational cycles also present challenges. This study integrates computational fluid dynamics (CFD) with molecular-level reaction kinetics (MRK), incorporates a genetic simulated annealing (GSA) algorithm, and systematically accounts for reactor geometry, internal fluid flow, heat and mass transfer mechanisms, along with catalyst deactivation kinetics, to establish a multiscale CFD-MRK hybrid model. Through rigorous validation with over two years of long-term industrial data, the model demonstrates high predictive accuracy and robustness for both concentration and temperature fields. Furthermore, the model delineates the distribution of core molecules across the reactor and identifies a potential high-temperature zone near the bottom head of the catalyst bed. Validation results confirm that the developed CFD-MRK model can serve as an effective numerical tool for molecular management and long-term stable operation in industrial isomerization processes.