Hydrocarbon lift system for the conversion of hydrocarbons and the separation of fines

Claim 1

IN A HYDROCARBON CONVERSION PROCESS WHEREIN A BODY OF GRANULAR CATALYST IS CONTINUOUSLY CIRCULATED THROUGH A CLOSED SYSTEM INCLUDING HYDROCARBON CONVERSION AND CATALYST REGENERATION ZONES THROUGH EACH OF WHICH SAID CATALYST GRAVITATES AS A COMPACT MOVING MASS, AND WHEREIN REGENERATED CATALYST WITHDRAWN FROM SAID REGENERATION ZONE IS ELEVATED BY A STREAM OF GASEOUS HYDROCARBONS THROUGH A CONFINED LIFT PATH FOR RETURN TO SAID CONVERSION ZONE, THE METHOD OF REMOVING CATALYST FINES FROM SAID CIRCULATING BODY OF CATALYST WHICH COMPRISES THE STEPS OF: CONTINUOUSLY REMOVING A MINOR PORTION OF FRESH REGENERATED CATALYST FROM SAID SYSTEM; ENGAGING SAID MINOR PORTION OF REGENERATED CATALYST WITH A STREAM OF INERT LIFT GAS; CONVEYING SAID MINOR PORTION OF REGENERATED CATALYST BY MEANS OF SAID INERT LIFT GAS UPWARDLY THROUGH A SECOND CONFINED LIFT PATH TO AN ELEVATED ELUTRIATION ZONE; PASSING THE CATALYST-CONVEYING STREAM OF INERT LIFT GAS THROUGH SAID ELUTRIATION ZONE AT SUCH REDUCED VELOCITY THAT THE PARTICLES OF CATALYST OTHER THAN FINES BECOME DISENGAGED FROM THE GAS STREAM AND SETTLE TO THE BOTTOM OF SAID ELUTRIATION ZONE; DISCHARGING SAID INERT GAS TOGETHER WITH ENTRAINED FINES FROM THE UPPER END OF SAID ELUTRIATION ZONE; DISCHARGING THE DISENGAGED COARSER PARTICLES OF CATALYST FROM THE BOTTOM OF SAID ELUTRIATION ZONE; AND RETURNING SAID COARSER PARTICLES TO SAID CIRCULATING BODY OF CATALYST.