Fluidized solids transfer with a valve erosion reduction method and apparatus

Claim 1

A METHOD FOR CONVERTING A HYDROCARBON IN THE PRESENCE OF A FLUIDIZED CATALYST WHICH COMPRISES IN COMBINATION THE STEPS AS FOLLOWS: (1) ADMIXING SAID HYDROCARBON WITH SAID CATALYST AND (2) CONVEYING SIAD ADMIXTURE THROUGH A TRANSFER PIPE INTO A REACTOR VESSEL, MAINTAINED UNDER HYDROCARBON CONVERSION CONDITIONS, AND (3) MAINTAINING A BED OF DENSE PHASE HYDROCARBON AND CATALYST MIXTURE IN SAID REACTOR FOR A TIME SUFFICIENT TO CONVERT SAID HYDROCARBON, (4) REMOVING SPENT CATALYST FROM SAID BED INTO A TRANSFER PIPE, LOCATED IN A SUBSTANTIALLY UPRIGHT POSITION BELOW SAID REACTOR, (5) FROM SAID LAST-MENTIONED PIPE BY WAY OF A WITHDRAWAL VALVE REMOVING SAID CATALYST INTO ANOTHER TRANSFER PIPE FOR ADMIXTURE WITH TRANSPORT GASES AND (6) TRANSPORTING THE SAID ADMIXTURE TO A REGENERATOR VESSEL, (7) IN SAID VESSEL REGENERATING SAID CATALYST UNDER REGENERATING CONDITIONS, (8) WITHDRAWING REGENERATED CATALYST FROM SAID REGENERATOR THROUGH A TRANSFER PIPE LOCATED IN A SUBSTANTIALLY UPRIGHT POSITION BELOW SAID REGENERATOR, (9) PASSING SAID REGENERATED CATALYST THROUGH A WITHDRAWAL VALVE FROM SAID LASTMENTIONED PIPE INTO SAID FIRST-MENTIONED TRANSFER PIPE (10) ADMIXING SAID HYDROCARBON FOR TRANSFER TO SAID REACTOR AS DESCRIBED, (11) MAINTAINING INEACH OF SIAD SUBSTANTIALLY UPRIGHT POSITIONED TRANSFER PIPES ABOVE SAID WITHDRAWAL VALVES THEREIN A LEVEL OF DENSE PHASE FLUIDIZED CATALYST AND CONTROLLING THE LEVEL OF THE DENSE PHASE OF FLUIDIZED CATALYST IN SAID PIPES BY MEANS OF A SECOND VALVE IN EACH OF SAID PIPES POSITIONED ABOVE EACH OF SAID WITHDRAWAL VALVES BY OPERATING SAID SECOND VALVES RESPONSIVE TO THE PRESSURE DIFFERENTIAL ACROSS EACH OF SAID WITHDRAWAL VALVES, RESPECTIVELY, TO MAINTAIN SAID PRESSURE DIFFERENTIAL BELOW A PREDETERMINED MAXIMUM.

Claim 2

A METHOD FOR CONVERTING A HYDROCARBON IN THE PRESENCE OF A FLUIDIZED CATALYST WHICH COMPRISES IN COMBINATION THE STEPS AS FOLLOWS: (1) ADMIXING SAID HYDROCARBON WITH SAID CATALYST AND (2) CONVEYING SIAD ADMIXTURE THROUGH A TRANSFER PIPE INTO A REACTOR VESSEL, MAINTAINED UNDER HYDROCARBON CONVERSION CONDITIONS, AND (3) MAINTAINING A BED OF DENSE PHASE HYDROCARBON AND CATALYST MIXTURE IN SAID REACTOR FOR A TIME SUFFICIENT TO CONVERT SAID HYDROCARBON, (4) REMOVING SPENT CATALYST FROM SAID BED INTO A TRANSFER PIPE, LOCATED IN A SUBSTANTIALLY UPRIGHT POSITION BELOW SAID REACTOR, (5) FROM SAID LAST-MENTIONED PIPE BY WAY OF A WITHDRAWAL VALVE REMOVING SAID CATALYST INTO ANOTHER TRANSFER PIPE FOR ADMIXTURE WITH TRANSPORT GASES AND (6) TRANSPORTING THE SAID ADMIXTURE TO A REGENERATOR VESSEL, (7) IN SAID VESSEL REGENERATING SAID CATALYST UNDER REGENERATING CONDITIONS, (8) WITHDRAWING REGENERATED CATALYST FROM SAID REGENERATOR THROUGH A TRANSFER PIPE LOCATED IN A SUBSTANTIALLY UPRIGHT POSITION BELOW SAID REGENERATOR, (9) PASSING SAID REGENERATED CATALYST THROUGH A WITHDRAWAL VALVE FROM SAID LASTMENTIONED PIPE INTO SAID FIRST-MENTIONED TRANSFER PIPE (10) ADMIXING SAID HYDROCARBON FOR TRANSFER TO SAID REACTOR AS DESCRIBED, (11) MAINTAINING INEACH OF SIAD SUBSTANTIALLY UPRIGHT POSITIONED TRANSFER PIPES ABOVE SAID WITHDRAWAL VALVES THEREIN A LEVEL OF DENSE PHASE FLUIDIZED CATALYST AND CONTROLLING THE LEVEL OF THE DENSE PHASE OF FLUIDIZED CATALYST IN SAID PIPES BY MEANS OF A SECOND VALVE IN EACH OF SAID PIPES POSITIONED ABOVE EACH OF SAID WITHDRAWAL VALVES BY OPERATING SAID SECOND VALVES RESPONSIVE TO THE PRESSURE DIFFERENTIAL ACROSS EACH OF SAID WITHDRAWAL VALVES, RESPECTIVELY, TO MAINTAIN SAID PRESSURE DIFFERENTIAL BELOW A PREDETERMINED MAXIMUM.