REGENERATION STRATEGIES FOR COKED FIXED-BED REACTORS

A two-zone grain-pellet model has been used to simulate catalyst regeneration in fixed bed reactors. Changes in coke composition during reaction and non-uniform coke distributions in the reactor have been accounted for, as well as inter- and intraparticle heat and mass transfer resistances. The model calculates the temperature rise at each axial position in the reactor during regeneration. Coke conversion profiles in the bed and temperature profiles within the catalyst particle are also calculated for different operating conditions. The results are examined in view of the regeneration rate achieved and of the extension of the high-temperature zone generated in the reactor. © 1990.