Resid cracking process and apparatus

Abstract From the Canadian patent

This application is directed to a process and apparatus for regenerating an elutriable mixture of fluidized catalytic cracking (FCC) catalyst and a demetallizing additive. Deactivated catalyst and coke-containing additive are added to a single dense bed regenerator. Within the regenerator, differences in settling velocity segregate the elutriable mixture into a lower dense bed containing most of the additive and a contiguous upper dense bed containing most of the FCC catalyst. Some regeneration gas is added to the lower dense bed to at least partially decoke the additive while additional regeneration gas is added to the upper dense bed. Decoked additive and regenerated FCC catalyst are …