Method and device for catalytic cracking comprising reactors with descending and ascending flows

An apparatus for fluidized bed or entrained bed catalytic cracking of hydrocarbon feed comprising:

• a substantially vertical dropper reactor (1) with an upper inlet and a lower outlet;
• a first means (101) for supplying regenerated catalyst connected to at least one regenerator for used catalyst and connected to said upper inlet;
• a first means (102) for supplying atomized feed disposed below the first catalyst supply means;
• a first separation vessel (105) for separating catalyst from a gas phase connected to the lower outlet from the first dropper reactor (1) and having an outlet (106) for gas phase and an outlet for coked catalyst;
• a substantially vertical riser reactor (2) having a lower inlet and an upper outlet;
• a second means (110) for supplying catalyst connected to the outlet for coked catalyst of said first separation vessel (105) and to the lower inlet of said riser reactor;
• a second means (202) for supplying feed located above the lower inlet of said riser reactor;
• a second separation vessel (203) for separating used catalyst from a second gas phase connected to said upper outlet of said riser reactor, the second separation vessel (203) comprising a catalyst stripping chamber (212) and having an upper outlet (206) for a gas phase and a lower outlet (7) for used catalyst, said lower outlet being connected to a first regenerator (301).