A CONTINUOUS CRYOPUMP/PELLET-FABRICATION APPARATUS FOR FUSION

FUSION REACTORS BASED ON THE MAGNETIC CONFINEMENT OF PLASMAS WILL REQUIRE ACTIVE FUELING TO REPLENISH THE DEUTERIUM/TRITIUM ESCAPING THE PLASMA. CRYOGENIC PUMPS AND FROZEN PELLET INJECTION ARE THE MOST EFFICIENT MEANS OF PUMPING AND REFUELING THE TOKAMAK PLASMA. SINCE THE BURN RATE OF THE REACTOR IS ONLY A FEW PERCENT, HOWEVER, THE EXHAUST FUEL WILL HAVE LARGE QUANTITIES OF UNREACTED DEUTERIUM AND TRITIUM. SINCE TRITIUM IS A RADIOACTIVE GAS IT IS IMPORTANT TO LIMIT THE TOTAL TRITIUM INVENTORY OF THE REACTOR TO A MINIMUM. THIS WILL REQUIRE RAPID RECYCLING OF THE TRITIUM PUMPED FROM THE REACTOR INTO THE PELLET FUEL INJECTION SYSTEM. THIS PROJECT WILL ACCOMPLISH THIS WITH A CONTINUOUS CRYOGENIC FOREPUMP WHICH WILL RECEIVE THE EXHAUST FROM THE PRIMARY PUMPING SYSTEM AND PRODUCE HIGH QUALITY FROZEN DEUTERIUM/TRITIUM PELLETS SUITABLE FOR DIRECTLY FEEDING A CENTRIFUGE PELLET INJECTOR. THE CRYOPUMP WILL THUS BE ABLE TO GREATLY REDUCE THE TRITIUM INVENTORY BY RECYCLING THE FUEL BACK INTO THE PLASMA WITHIN A FEW MINUTES FROM THE TIME THE FUEL ENTERS THE PUMP. IN ADDITION THE PROPOSED PUMP/PELLET FABRICATION APPARATUS CONSISTS OF A SINGLE CRYOPANEL WHICH WILL BOTH PUMP AND PRODUCE PELLETS WITH NO MOVING PARTS, THEREBY GREATLY INCREASING THE RELIABILITY AND REDUCING THE COST OF THE APPARATUS AS COMPARED TO CONVENTIONAL PUMPING AND PELLET FUELING SYSTEMS. IN PHASE I A SMALL PUMP WILL BE CONSTRUCTED WHICH WILL DEMONSTRATE THE CAPABILITY OF PRODUCING DEUTERIUM PELLETS, AND A CONCEPTUAL DESIGN OF A FULL SCALE REACTOR SYSTEM, TO BE CONSTRUCTED AND TESTED AS A PHASE II EFFORT, WILL BE PRODUCED.