Pneumatic solids transfer in a conversion process

Claim 1

IN A CONTINUOUS METHOD OF CONVERTING RESIDUAL HYDROCARBONS IN A CLOSED SYSTEM INTO COKE AND LIGHTER HYDROCARBONS IN WHICH SOLID PARTICLES OF AT LEAST 1/16 INCH MAJOR DIMENSION ARE HEATED IN A REHEAT ZONE TO A TEMPERATURE IN THE RANGE OF 850-1100*F. AND ARE CONVEYED TO A REACTION ZONE MAINTAINED AT SUPERAMOSPHERIC PRESSURE FOR PASSAGE THERETHROUGH BY GRAVITY AS A RELATIVELY DEEP, UNAGITATED, FREE-FLOWING HOMOGENEOUS AND CONTINUOUS COLUMN AND ON WHICH A CHARGE COMPRISING RESIDUAL HYDROCARBONS SUBSTANTIALLY IN LIQUID PHASE AND BELOW THE TEMPERATURE OF INCIPIENT COKING IS COATED SO THAT THE INITIALLY UNVAPORIZED PORTION OF THE CHARGE WILL MOVE DOWNWARDLY WITH SAID COLUMN ON SAID PARTICLES AND IN WHICH THE PARTICLES OF THE MOVING COLUMN ARE RETAINED IN SAID REACTION ZONE AFTER SAID CHARGE COATING AND WITHOUT OTHER ADDITION OF HEAT OR FURTHER ADDITION OF CHARGE FOR AT LEAST 5 MINUTES AND FOR A TIME SUFFICIENT TO CONVERT THE INITIALLY UNVAPORIZED PORTION OF THE CHARGE INTO DRY SOLID COKE ADHERING TO THE PARTICLES OF SAID COLUMN AND VAPOROUS LIGHTER HYDROCARBONS SOLELY BY THE HEAT SUPPLIED BY THE HEATED PARTICLES FORMING SAID COLUMN AND IN WHICH THE VAPOROUS LIGHTER HYDROCARBONS ARE REMOVED FROM SAID MOVING COLUMN IN THE REACTION ZONE, SAID COKE BEARING PARTICLES BEING REMOVED FROM SAID REACTION ZONE AND CONVEYED TO SAID REHEAT ZONE IN SAID CLOSED SYSTEM, THE IMPROVEMENT WHICH COMPRISES: INTRODUCING AN INERT STRIPPING GAS INTO SAID REACTION ZONE TO STRIP SAID VAPOROUS HYDROCARBONS FROM SAID PARTICLES; REMOVING SAID VAPOROUS HYDROCARBONS AND A PORTION OF SAID INERT STRIPPING GAS FROM SAID REACTION ZONE; CONVEYING SAID PARTICLES AND ADHERING COKE TOGETHER WITH THE REMAINING PORTION OF SAID INERT STRIPPING GAS THROUGH A CONFINED LIFT LEG TO AN ELEVATED HOPPER WHILE SUBSTANTIALLY PREVENTING THE PASSAGE OF SAID VAPOROUS HYDROCARBONS THROUGH SAID LIFT LEG, SAID REMAINING PORTION OF SAID INERT STRIPPING GAS PROVIDING THE LIFTING MEDIUM REQUIREMENTS FOR SAID LIFT LEG; INTGERCEPTING THE UPWARD CONE OF FLOW ANGLE OF THE DENSE PACKED SOLIDS AT THE HOPPER EXIT OF THE LIFT LEG THEREBY MAINTAINING MAXIMUM PARTICLE PACKING DENSITY CONDITIONS THROUGHOUT SAID LIFT LEG; AND THROTTLING THE WITHDRAWAL RATE OF THE PARTICLES FROM SAID HOPPER TO THE REHEAT ZONE SO AS TO MAINTAIN A SUBSTANTIALLY CONSTANT AND CONTINUOUS INVENTORY AND UNIFORM FLOW OF SOLIDE IN THE COLUMNS IN SAID REACTION ZONE AND LIFE LEG.