Method and apparatus for transferring granular solids

Claim 1

IN A METHOD FOR TRANFERRING GRANULAR SOLIDS FROM A HIGH PRESSURE ZONE TO A RELATIVELY LOWER PRESSURE ZONE WHEREIN SOLIDS FLOW FROM THE HIGH PRESSURE ZONE TO THE LOW PRESSURE ZONE AS A SUBSTANTIALLY COMPACT COLUMN OF RESTRICTED CROSS-SECTION COMPARED TO THAT OF BOTH ZONES, THE IMPROVEMENT WHICH COMPRISES: MAINTAINING A SUBSTANTIALLY COMPACT BED OF GRANULAR SOLIDS IN THE LOWER PRESSURE ZONE, DELIVERING THE SOLIDS FROM THE COLUMN TO THE BED, PASSING GAS FROM SAID HIGH PRESSURE ZONE TO SAID LOWER PRESURE ZONE THROUGH SAID COLUMN AT A RATE SUCH THAT THE AVERAGE PRESSURE GRADIENT THROUGH SAID COLUMN IS GREATER THAN 1 POUND PER SQUARE INC PER FOOT OF COLUMN LENGTH, CONFINING THE BED SO AS TO PREVENT UPWARD MOVEMENT OF ALL PARTICLES DESIRED TO BE RETAINED IN THE SYSTEM WHILE PERMITTING GAS TO ESCAPTE UPWARDLY, WITHDRAWING THE GAS FROM THE LOW PRESSURE ZONE AT A LEVEL ABOVE SAID BED AND WITHDRAWING GRANULAR SOLIDS FROM THE SAID BED AT A RATE CONTROLLED TO MAINTAIN THE GANULAR SOLIDS IN THE TRANFER SYSTEM IN A COMPACTED CONDITION.