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INL makes first fuel for Molten Chloride Reactor Experiment
Idaho National Laboratory has announced the creation of the first batch of enriched uranium chloride fuel salt for the Molten Chloride Reactor Experiment (MCRE). INL said that its fuel production team delivered the first fuel salt batch at the end of September, and it intends to produce four additional batches by March 2026. MCRE will require a total of 72–75 batches of fuel salt for the reactor to go critical.
W. Breitung, S. A. Wright
Nuclear Science and Engineering | Volume 105 | Number 4 | August 1990 | Pages 303-318
Technical Paper | doi.org/10.13182/NSE90-A21467
Articles are hosted by Taylor and Francis Online.
Irradiated (U.Pu)-mixed oxide with 5% burnup was heated in the pulsed Annular Core Research Reactor at Sandia National Laboratories. The tests were typical of prompt Bethe-Tait excursions in terms of heating method (nuclear fission), heating period (milliseconds), and temperatures attained (up to 7700 K). Fission products provided high pressures at temperatures at which fresh fuel shows only a negligible vapor pressure. Fission product release became measurable as soon as the temperature exceeded the steady-state irradiation temperature of the fuel sample. The fission product pressures reached 1.3 to 2.5 MPa at 3000 K over solid fuel, and 2.5 to 5 MPa at 4000 K over liquid fuel. The total amount of fission product released corresponded to ∼30 to 75% of the fission gas inventory. The amount of fission product released increased with the fuel heating rate. Under rapid heating, the total pressure over irradiated (U,Pu) oxide is controlled by a suppression mechanism. At any given temperature, the gaseous components (xenon, cesium, and ambient gas) suppress fuel boiling if their pressure pgas is higher than the fresh fuel saturation vapor pressure psat of unirradiated fuel. If psat exceeds pgas, the total pressure is, to a first approximation, equal to Psat. Under millisecond heating, the total pressure from irradiated fuel may be taken as ptot = max(Pgas,Psat).
