Catalyst addition process and apparatus

Claim 1

IN A PROCESS WHEREIN A BODY OF GRANULAR CATALYST IS CONTINUOUSLY CIRCULATED AT RELATIVELY HIGH TEMPERATURE THROUGH A SYSTEM COMPRISING A CATALYST REGENERATION ZONE, AND WHEREIN FRESH RELATIVELY COOL CATALYST IS GRADUALLY ADDED TO SAID BODY AS MAKE UP FOR SMALL QUANTITIES OF CATALYST REMOVED THEREFROM, THE STEPS WHICH COMPRISE: WITHDRAWING A MINOR PORTION OF HOT REGENERATED CATALYST FROM SAID CIRCULATING BODY; INTRODUCING SAID PORTION OF REGENERATED CATALYST INTO THE UPPER REGION OF A CONFINED VERTICALLY ELONGATED HEAT EXCHANGE ZONE; INTRODUCING SAID FRESH CATALYST INTO SAID UPPER REGION; PASSING SAID REGENERATED CATALYST AND SAID FRESH CATALYST DOWNWARDLY WITHIN SAID UPPER REGION AS SEPARATE COMPACT MOVING STREAMS MERGING THEREBELOW TO FORM A SINGLE COMPACT MOVING COLUMN COMPOSED OF ADJACENT CONTACTING VERTICAL STRATA OF HOT REGENERATED CATALYST AND RELATIVELY COOL FRESH CATALYST, WHEREBY THE RATE OF FLOW OF SAID STREAMS OF CATALYST ONTO SAID COLUMN IS DIRECTLY PROPORTIONAL TO THEIR RESPECTIVE FLOW AREAS; PASSING SAID COLUMN OF CATALYST DOWNWARDLY THROUGH THE REMAINING PORTION OF SAID HEAT EXCHANGE ZONE; INTRODUCING A GASEOUS HEAT EXCHANGE MEDIUM AT THE LOWER END OF SAID ZONE FOR GENERALLY COUNTERCURRENT FLOW THROUGH SAID COLUMN; DISENGAGING THE MAJOR PORTION OF SAID GAS FROM SAID COLUMN AT EACH OF A PLURALITY OF SPACED INTERMEDIATE LEVELS THEREALONG AND AT ALTERNATE OPPOSITE SIDES THEREOF, AND DIRECTLY REINTRODUCING EACH DISENGAGED PORTION OF GAS AT A HIGHER LEVEL ALONG THE SAME SIDE OF SAID COLUMN BUT BELOW THE NEXT-SUCCEEDING DISENGAGING LEVEL, WHEREBY SUCH REINTRODUCED GAS IS CAUSED TO FLOW LATERALLY THROUGH SAID COLUMN BETWEEN SUCH REINTRODUCTION AND DISENGAGEMENT LEVELS; DISCHARGING SAID GAS AT THE UPPER END OF SAID ZONE, DISCHARGING THE ADMIXTURE OF REGENERATED AND FRESH CATALYST AT THE BOTTOM OF SAID HEAT EXCHANGE ZONE; AND PASSING SAID ADMIXTURE OF CATALYST TO SAID CIRCULATING BODY OF SOLIDS.