Patent ID: 6383965
Filing Date: 2002-05-07
Classification: B01J

Abstract:
A process for regenerating a spent molecular sieve catalyst comprising the steps of:(1) mixing a high temperature flue gas that comes from a second group of cyclones with the spent catalyst in a first riser regenerator to form a mixture of a half-rengenerated catalyst and a flue gas at the top of the first riser regenerator; (2) separating the half-regenerated catalyst from the mixture formed in step 1 in a first group of cyclones; (3) mixing the half-regenerated catalyst that comes from the first group of cyclones with a sufficient amount of air for burning off all coke on the spent catalyst in a second riser rengerator to form a mixture of a high temperature flue gas and a regenerated catalyst at the top of the second riser regenerator; (4) separating the regenerated catalyst from the mixture formed in step 3in the second group of cyclones; and (5) recovering surplus heat from the renegerated catalyst that comes from the second group of cyclones by a regenerated catalyst cooler which is located outside of the second riser regenerator.