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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Surplus plutonium for power reactor fuel: What’s on offer
The Department of Energy has a plan for private companies to “dispose of surplus plutonium”—about 19.7 metric tons in both oxide and metal forms—by “making the materials available for advanced nuclear technologies.” A Surplus Plutonium Utilization Program request for applications (RFA) issued October 21 describes the plutonium on offer, and the “thresholds” prospective applicants must meet.
B. P. Bromley, Z. Cheng, A. Nava Dominguez, A. V. Colton
Nuclear Technology | Volume 207 | Number 10 | October 2021 | Pages 1511-1537
Technical Paper | doi.org/10.1080/00295450.2020.1827658
Articles are hosted by Taylor and Francis Online.
This paper reports the results of subchannel thermal-hydraulic studies (using the ASSERT-PV code) of the effects of variations and uncertainties in operating/boundary conditions and geometry on the predictions of pressure drop, dryout power, and dryout location for two types of advanced, nonconventional fuels in a pressure tube heavy water reactor (PT-HWR) fuel channel with 12 fuel bundles. The fuel bundles tested include a 37-element fuel bundle made with SEUO2 (1.2 wt% 235U/U), with a central fuel element made of ThO2, and 35-element fuel bundle made with (LEU,Th)O2, using 5 wt% 235U/U low-enriched uranium (LEU), 50 wt% LEUO2, and 50 wt% ThO2. Results indicate that for a range of flow conditions, the dryout power for the thorium-based 35-element fuel bundle is 10% to 26% higher than that for the uranium-based 37-element fuel bundle. Variation/uncertainty in the pressure tube diameter has the most significant impact on the pressure drop, dryout power, and dryout location. Results from these studies may have implications for the operations of PT-HWRs with advanced fuels, and further modifications may be desirable to further enhance thermal-hydraulic margins.