Patent ID: 7008595

Claim:
A fluidized bed catalytic cracking apparatus, said apparatus comprising: a riser ( 35 ) containing a feed stock, regenerated catalyst and adsorbent and having a first inlet means ( 31 ) for introduction of high velocity steam, a second inlet means ( 61 ) for introduction of the reactivated adsorbent, a third inlet means ( 32 ) for introduction of the feed stock containing heavy residual fractions with high concentrations of conradson carbon content, metals including vanadium and nickel and additional poisons including nitrogen, a fourth inlet means ( 34 ) for introduction of the regenerated catalyst, an outlet ( 35 A) of the riser is connected to riser termination devices/cyclones ( 39 A, 39 B, 40 A and 40 B) for causing separation of hydrocarbon vapors from adsorbent-catalyst mixture, the cyclones having dip legs extended towards stripper cum separator ( 37 ) drops catalyst-adsorbent mixture close to the interface of catalyst and adsorbent bed; a reactor ( 38 ) comprising said cyclones and having an outlet ( 41 ) for taking out hydrocarbon vapors and steam mixture to fractionator(s); a stripper cum separator ( 37 ) located at the bottom of the reactor for causing removal of strippable hydrocarbons from spent catalyst and coked adsorbent mixture and segregating catalyst from adsorbent; said stripper cum separator is with or without baffles/internals having an inlet ( 36 ) at its base for introduction of steam in the upward direction so as to provide a superficial velocity sufficient to strip off all hydrocarbons and to segregate solids into two layers a, layer of spent catalyst ( 62 ) and another layer of coked adsorbent ( 63 ), an outlet at the bottom of the stripper cum separator for taking out coked adsorbent through a standpipe ( 52 ) via valve means ( 53 ), another outlet at an intermediate location above the said adsorbent outlet ( 52 ) for removing spent catalyst through a standpipe ( 42 ) via a valve means ( 43 ); an adsorbent regenerator ( 54 ) located below the level of the lower portion of the stripper cum separator for receiving the coked adsorbent from the bottom portion of the stripper cum separator and causing reactivation of adsorbent thereof; an inlet ( 59 ) in the adsorbent regenerator for introduction of air or oxygen containing gas or steam, an outlet ( 60 ) in flow communication with the second inlet ( 32 ) of the riser for introduction of reactivated adsorbent; and another outlet ( 57 ) at its top for the disposal of flue gas; a catalyst regenerator ( 44 ) situated above the adsorbent regenerator but below the stripper cum separator is connected to the stripper cum separator by the stand pipe ( 42 ), an inlet ( 49 ) at the base of the regenerator for introducing air or oxygen containing gas for effectively burning coke deposited on the catalyst, an outlet ( 50 ) in flow communication with the fourth inlet of riser ( 34 ) via valve means ( 51 ) for introduction of regenerated catalyst; and another outlet ( 47 ) at its top for disposal of flue gas.