摘要 |
<p>A process and apparatus (Figs. 1, 2, 3 and 4) for controlled, multi-stage regeneration of FCC catalyst is disclosed. A modified high-efficiency catalyst regenerator (80), with a fast fluidized bed coke combustor (62), dilute phase transport riser (83), and second fluidized bed (82) regenerates the catalyst in at least two stages. The primary stage of regeneration is in the coke combustor (62). Second stage catalyst regeneration occurs in the second fluidized bed (82). The amount of combustion air added to both regeneration stages is set to maintain partial CO combustion in both stages. Controlled multi-stage regeneration reduces the steaming or deactivation of catalyst during regeneration, maximizes coke burning capacity of the regenerator (80), and minimizes or eliminates NOx emissions.</p> |