Improved fluid catalytic cracking process and apparatus.

摘要

A fluidized bed catalytic cracking process and apparatus are disclosed. Hydrocarbon feed and catalyst are introduced into a vertical riser reactor (1). Catalyst and cracked hydrocarbons exit a downstream end (5) of the riser reactor. Catalyst is deflected down to a primary stripper (17). Entrained catalyst, which was not deflected, is separated from the cracked hydrocarbons in a cyclone separator (21) and discharged via a dipleg. Stripped catalyst from the primary stripper (17) passes to a secondary stripper (23) and then to a first stage regenerator (33), which partially regenerates the catalyst, and a second stage regenerator (29) which completes the regeneration. The resulting hot regenerated catalyst is recycled to the secondary stripper to aid in stripping and to the riser (1) to crack the hydrocarbon feed. A mixing tray (31) between the primary and secondary strippers may be used to mix catalyst from the primary stripper, and the cyclone dipleg with hot regenerated catalyst prior to passage of the mixture into the secondary stripper (23).