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Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2023)
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Show support for a Lego nuclear power plant
A creative fan of Lego—and nuclear power—has designed a nuclear power plant out of the famous building blocks and has submitted the idea to the Lego Group for possible production—but first, the idea needs the support of the public.
Nuclear Technology | Volume 207 | Number 12 | December 2021 | Pages 1793-1809
Technical Paper | doi.org/10.1080/00295450.2020.1846987
Articles are hosted by Taylor and Francis Online.
Although η, the number of neutrons released per neutron absorbed in a 232Th-233U (thorium) fuel cycle, is greater than 2 in the thermal spectrum and therefore the possibility of breeding in a water-moderated reactor exists, it has been found difficult to achieve in practice. It is useful to relax the constraint for breeding and examine a thorium cycle for pressurized water reactors PWRs, denoted as PWR-Th, with the provision that the shortfall be made up by 233U bred in a PWR operating on a uranium fuel cycle, denoted as PWR-U, both of which utilize bimetallic thorium-zirconium alloy cladding as part of the fuel rod design. The number of complementary PWRs that could be sustainably operated on a thorium cycle was seen to critically depend on the moderator-to-fuel ratio (MF). Detailed cycle-by-cycle analysis shows that at the end of the first cycle, the sustainability ratio, namely, the ratio of sustainable PWR-Th reactors to PWR-U reactors, is 1.07 at an MF of 1.91, 1.4 at an MF of 1.43, and 4.45 at an MF of 0.954. The shortfall in 233U was found to decrease continually in subsequent cycles with the sustainability ratio increasing to 1.45, 2.01, and 28.3 at the respective MF values of 1.91, 1.43, and 0.954 by the 25th cycle. Although the sustainability ratio increases with lower MF, the achievable discharge exposure decreases necessitating larger material throughput in reprocessing. Detailed evaluations for fuel thermal, mechanical performance and nuclear reactivity feedback parameters require a further narrowing of potential design parameters based on holistic considerations arising from reprocessing. The PWR-Th reactors generate only trace amounts of transuranic (TRU) waste, and combined with a PWR-U design with bimetallic thorium cladding that generates only a fourth of the TRU waste compared to the standard all-UO2 fuel cycle, a significant reduction in TRU waste is possible.