Eslinger Paul W, Johnson Christine M, McIntyre Justin I, Simpson Cheslan K, Slack Johnathan L, Burnett Jonathan L
Pacific Northwest National Laboratory, 902 Battelle Blvd., Richland, WA, 99354, USA.
J Environ Radioact. 2021 Aug;234:106622. doi: 10.1016/j.jenvrad.2021.106622. Epub 2021 May 6.
Molten salt reactors (MSRs) are gaining support as many countries look for ways to increase power generation and replace aging nuclear energy production facilities. MSRs have inherently safe designs, are scalable in size, can burn transuranic wastes from traditional solid fuel nuclear reactors, can store excess heat in thermal reservoirs for water desalination, and can be used to produce medical isotopes as part of the real-time liquid-fuel recycling process. The ability to remove Xe in real time from the fuel improves the power production in an MSR because Xe is the most significant neutron-absorbing isotope generated by nuclear fission. Xenon-135, and other radioactive gases, are removed by sparging the fuel with an inert gas while the liquid fuel is recirculated from the reactor inner core through the heat exchangers. Without effective abatement technologies, large amounts of radioactive gas could be released during the sparging process. This work examines the potential impact of radioxenon releases on samplers used by the International Monitoring System (IMS) to detect nuclear explosions. Atmospheric transport simulations from seven hypothetical MSRs on different continents were used to evaluate the holdup time needed before release of radioxenon so IMS samplers would register few detections. Abatement technologies that retain radioxenon isotopes for at least 120 d before their release will be needed to mitigate the impacts from a molten salt breeder reactor used to replace a nuclear power plant. A holdup time of about 150 d is needed to reduce emissions to the average level of current nuclear power plants.
随着许多国家寻求增加发电量并替换老化的核能生产设施，熔盐反应堆（MSR）正获得越来越多的支持。熔盐反应堆具有本质安全的设计，规模可扩展，能够燃烧传统固体燃料核反应堆产生的超铀废物，可将多余的热量存储在热库中用于海水淡化，并且可作为实时液体燃料再循环过程的一部分用于生产医用同位素。由于氙是核裂变产生的最重要的中子吸收同位素，因此能够实时从燃料中去除氙可提高熔盐反应堆的发电量。通过在液体燃料从反应堆堆芯通过热交换器再循环时用惰性气体鼓泡燃料，可去除氙 - 135和其他放射性气体。如果没有有效的减排技术，在鼓泡过程中可能会释放大量放射性气体。这项工作研究了放射性氙释放对国际监测系统（IMS）用于探测核爆炸的采样器的潜在影响。利用来自不同大陆的七个假设熔盐反应堆的大气传输模拟来评估放射性氙释放前所需的滞留时间，以便国际监测系统采样器几乎检测不到。需要有能在释放前至少保留放射性氙同位素120天的减排技术，以减轻用于替换核电站的熔盐增殖反应堆的影响。需要约150天的滞留时间才能将排放量降低到当前核电站的平均水平。
