Method and apparatus for continuously transforming plutonium oxalate into plutonium oxide

An apparatus for transforming plutonium oxalate into plutonium oxide by drying and then calcining, the apparatus being disposed in a glove box having at least one face, and comprising:

• a generally cylindrical oven having an Archimedes screw mounted on a horizontal axis thereof, said screw being adapted to rotate about said horizontal axis, thereby transferring a heat-treated substance from a first zone of said oven where said substance is dried to a second zone of said oven where said substance is calcined;
• said oven including a body having:
• a first opening for permitting the feeding of the oven with plutonium oxalate at one end of the oven, adjacent to the first zone;
• a second opening for permitting emptying of the plutonium oxide from the oven at a second end of said oven, adjacent to the second zone;
• a third opening for permitting the injection of oxygen into said oven;
• and
• a fourth opening for permitting the extraction of gas from said oven;
• the oven further having housings, each housing being disposed in the body of the oven and opening outwardly with respect to the glove box on the exterior of the glove box, for receiving heater rods, said heater rods comprising at least one first rod and at least one second rod, said heater rods capable of being regulated to define temperature conditions inside said oven that are suitable for implementing drying in said first zone and calcining in said second zone longitudinally in the direction of the horizontal axis of the oven;
• and
• said at least one first rod for performing part of the drying of plutonium oxalate in said first zone;
• and
• said at least one second rod longer than said first rod both for performing part of the drying of plutonium oxalate in said first zone and for performing the calcining of the dried plutonium oxalate in said second zone;
• said first and second rods being accessible from said face of said glove box;
• gas extraction means suitable for extracting gas from said fourth opening while keeping the oven at negative pressure;
• and
• a filter assembly including a set of parallel filtering cartridges for removing entrained dust present in any gas extracted through said fourth opening by said gas extraction means, each filtering cartridge containing an undeformable filter medium, and being coupled to a nozzle having a sonic throat for unclogging said filter medium, in situ.