Apparatus for fluidized catalytic cracking of hydrocarbons

Claim 1

IN A FLUIDIZED CATALYTIC CRACKING REACTOR VESSEL COMPRISING AN ENCLOSED, VERTICALLY ELONGATED SHELL DEFINING A LOWER ZONE FOR FLUIDIZED CATALYST AND AN UPPER ZONE FOR SEPARATION AND RECOVERY OF HYDROCARBON VAPORS, AN ELONGATED RISE CONDUIT EXTENDING VERTICALLY INTO THE LOWER PORTION OF SAID REACTOR VESSEL FORMING AN UPWARDLY DIRECT CONFINED CRACKING PATH, AN ELONGATED DOWNCOMER CONDUIT, OPEN AT EACH END, VERTICALLY DISPOSED AROUND THE UPPER PORTION OF SAID ELONGATED RISER CONDUTI FORMING A DOWNWARDLY DIRECT ANNULAR CRACKING PATH COMMUNICATING AT THE LOWER END WITH THE INTERIOR OF SAID REACTOR VESSEL, AND FLOW REVERSAL MEANS COMMUNICATING WITH THE INTERIOR OF SAID RISE CONDUIT AND THE ANNULAR SPACE BETWEEN SAID RISER CONDUIT AND SAID DOWNCOMER CONDUIT AT THE UPPER END THEREOF; IMPROVED FLOW REVERSAL MEANS WHICH COMPRISE: A. A VERTICAL CYLINDER BODY ENCLOSING THE UPPER END OF SAID RISER CONDUIT AND THE UPPER END OF SAID DOWNCOMER CONDUIT; B. A BOTTOM RING, WHEREIN THE OUTER EDGE OF SAID RING IS ATTACHED TO THE LOWER EDGE OF SAID VERTICAL CYLINDER BODY AND THE INNER EDGE OF SAID RING IS ATTACHED TO THE UPPER EDGE OF SAID DOWNCOMER CNDUIT, THEREBY SPACING THE WALL OF SAID VERTICAL CYLINDER BODY FROM THE WALL OF SAID DOWNCOMER CONDUIT AND FORMING A VAPOR TIGHT SEAL THEREBETWEEN; C. A COVER PLATE ATTACHED TO THE UPPER END OF SAID VERTICAL CYLINDER BODY, HAVING AN OPENING OF SUBSTANTIALLY THE SAME DIAMETER AS THE RISER CONDUIT AND CONCENTRIC THEREWITH; D. A HOLLOW CYLINDRICAL MEMBER SURROUNDING THE OPENING IN SAID COVER PLATE; AND E. A TOP PLATE COVERING THE UPPER END OF SAID HOLLOW CYLINDRICAL MEMBER, WHEREIN THE PLANE SURFACE OF SAID TOP PLATE IS PERPENDICULAR TO THE VERTICAL AXIS OF SAID RISER CONDUIT.