Condon Caitlin A, Ivanusa Pavlo, Whiting Jonathan M, Mirick Patrick P, Bunn Amoret L, Varnum-Lowry Ciara B, Jensen Philip J
Pacific Northwest National Laboratory, USA.
Pacific Northwest National Laboratory, USA.
J Environ Radioact. 2021 Aug;234:106630. doi: 10.1016/j.jenvrad.2021.106630. Epub 2021 May 11.
Advanced nuclear reactor designs and advanced fuel types offer safety features that may reduce environmental consequences in an accident scenario when compared to conventional reactors and fuels. One advanced reactor fuel is tri-structural isotropic (TRISO) fuel particles which are approximately 0.9 mm in diameter. TRISO particle mobility, assuming the particle is unruptured and the encapsulated radionuclides are contained, was explored by a theoretical examination of transport through atmosphere, soil and groundwater, surface water, and non-human biota pathways. TRISO particles are too large and dense to travel in the atmosphere except under extreme conditions. TRISO particles are also too large to penetrate most soil profiles and so cannot be transported to or by groundwater. TRISO particles will settle out of the water column in surface waters and thus the transport will depend on the energy of the water body (e.g., waves or floods). TRISO particles could be transported by non-human biota. The size of TRISO particles could allow them to be intentionally ingested by non-human biota as a gastrolith or mimic something typical in an organism's diet. Generally, TRISO particles will have reduced environmental mobility compared to releases of radionuclides in the event of a conventional nuclear reactor accident. The extent of transport has implications in emergency planning zone designations and other considerations for licensing and deploying TRISO-fueled reactors. Further research and experimental work exploring TRISO particle mobility is required to understand the full environmental mobility of TRISO particles in the environment.
与传统反应堆和燃料相比，先进的核反应堆设计和先进的燃料类型具有一些安全特性，在事故情况下可能会减少对环境的影响。一种先进的反应堆燃料是三结构各向同性（TRISO）燃料颗粒，其直径约为0.9毫米。通过对其在大气、土壤、地下水、地表水和非人类生物群途径中的传输进行理论研究，探讨了TRISO颗粒的迁移性，前提是颗粒未破裂且封装的放射性核素未泄漏。TRISO颗粒太大、太重，除非在极端条件下，否则无法在大气中移动。TRISO颗粒也太大，无法穿透大多数土壤剖面，因此不能被地下水输送或通过地下水输送。TRISO颗粒会在地表水中从水柱中沉降出来，因此其传输将取决于水体的能量（如波浪或洪水）。TRISO颗粒可能会被非人类生物群运输。TRISO颗粒的大小可能使其被非人类生物群有意摄入，作为胃石或模仿生物体饮食中的典型物质。一般来说，与传统核反应堆事故中放射性核素的释放相比，TRISO颗粒在环境中的迁移性会降低。传输范围对应急规划区的划定以及许可和部署TRISO燃料反应堆的其他考虑因素具有影响。需要进一步开展研究和实验工作来探索TRISO颗粒的迁移性，以全面了解TRISO颗粒在环境中的迁移情况。
