Field Assisted Sintering of Nuclear Fuel Simulants

核燃料模拟物的现场辅助烧结

• 批准号: 2908917
• 金额: --
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2027
• 资助国家: 英国
• 起止时间: 2027 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2908917
• 关键词: Field; Assisted; Sintering; Nuclear; Fuel

The expected remaining lifetime of the UK's Advanced Gas-cooled Reactors (AGRs) will result in the generation of ~5,000t of AGR Spent Nuclear Fuel (SNF). The UK Nuclear Decommissioning Authority's (NDA's) preferred option for managing AGR SNF is interim storage - currently in ponds at the Sellafield site - prior to consignment to repository ca. 2075. AGR fuel pins consist of UO2 pellets sealed inside steel cladding tubes. Whilst in-reactor, some of the cladding can be rendered susceptible to in-pond corrosion, potentially leading to through-wall cladding failure. This may result in pondwater contamination by the SNF and inter-granular corrosion of the pellets themselves with loss of pellet integrity. Consequently, a transition to dry storage has been proposed - including the drying of wet stored SNF. This may carry further unknown risks which must be understood before implementation. Key knowledge gaps relating to this understanding include:1. A mechanistic understanding of how pondwater-exposed wet-stored spent UO2 fuel pellets corrode in both the absence and, especially, the presence of a radiation field; and 2. A mechanistic understanding of the possible drying processes of fuel pellets, again both in the presence and absence of radiation fields - but especially in wet-to-dry transitioned fuel with failed cladding and that may have been subject to in-pond corrosion processes.

英国先进气冷反应堆 (AGR) 的预计剩余寿命将产生约 5,000 吨 AGR 乏核燃料 (SNF)。英国核退役管理局 (NDA) 管理 AGR SNF 的首选方案是在寄送到储存库之前进行临时储存（目前位于塞拉菲尔德场地的池塘中）。 2075. AGR 燃料棒由密封在钢包壳管内的 UO2 颗粒组成。在反应堆内时，一些包壳可能容易受到池内腐蚀，可能导致穿墙包壳失效。这可能会导致池塘水被 SNF 污染以及颗粒本身的晶间腐蚀，从而导致颗粒完整性丧失。因此，有人建议向干式储存过渡，包括对湿式储存的 SNF 进行干燥。这可能会带来进一步的未知风险，在实施之前必须了解这些风险。与这种理解相关的主要知识差距包括：1．从机械原理上理解暴露于池水的湿式储存的废二氧化铀燃料芯块在不存在辐射场和尤其是存在辐射场的情况下如何腐蚀； 2. 对燃料芯块可能的干燥过程的机械理解，同样在存在和不存在辐射场的情况下 - 但特别是在包壳失效且可能遭受池内腐蚀的湿干过渡燃料中流程。