Safe-to-fail: Accident-tolerant fuel cladding

安全无故障：容灾燃料包壳

• 批准号: 580476-2022
• 负责人: Noel, JamesJJ
• 金额: $ 8.74万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Alliance Grants
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=747574
• 关键词: Safe; fail; Accident; tolerant; fuel

Conventional water-cooled nuclear reactors, including the current fleet of CANDU reactors and the small modular reactor (SMR) planned for construction at the Darlington nuclear power plant site, use uranium oxide fuel that is clad in protective tubes of a zirconium-tin alloy called Zircaloy. However, during a severe loss-of-coolant accident (LOCA) in a reactor, the reaction of the Zircaloy with high-temperature steam can generate large volumes of hydrogen, a gas that is explosive when mixed with air. Such a scenario previously played out during the Fukushima-Daiichi reactor accident in 2011, resulting in multiple hydrogen explosions. A variety of "accident tolerant fuel" (ATF) concepts have been explored to help decrease or eliminate the risk of cladding-steam reactions leading to hydrogen explosions under severe LOCA conditions. Much of this research has focused on either applying a protective coating to the Zircaloy to decrease its reactivity with steam under severe LOCA conditions or replacing Zircaloy with a material that would not react so dangerously during an accident. Unfortunately, the current suite of coatings and replacements are not durable enough to withstand a LOCA without significant degradation. Since Canada is now preparing to build new SMRs, there is considerable value in building expertise in ATF cladding to match that of other leading countries, such as the USA, France, and China. This knowledge will be particularly valuable for government decision-making and regulatory oversight and licensing of SMR construction and operation. The European Parliament has recently mandated that all reactors implement ATFs approved by their respective country's regulators in order to qualify as "green energy" sources. Implementing such policy and regulatory decisions in Canada will require a robust domestic understanding of the various factors related to ATF cladding performance, established by studying existing ATF cladding concepts and developing novel Canadian solutions. This research program aims to develop novel ATF claddings and to perform fundamental studies on existing ATF cladding concepts meant to eliminate the potential for hydrogen explosions during a severe LOCA.

常规的水冷核反应堆，包括目前计划在达灵顿核电站现场建造的小型模块反应器（SMR）的机队，使用氧化铀燃料，这些铀燃料被包裹在锆 - 锡合金的保护管中，称为锌锌。然而，在反应堆中发生严重的冷却剂事故（LOCA）期间，锆石与高温蒸汽的反应会产生大量的氢，这种氢与空气混合时是爆炸性的。这种情况以前在2011年的福岛 - 达吉反应堆事故中播出，导致了多次氢爆炸。已经探索了各种“意外耐药燃料”（ATF）概念，以帮助降低或消除在严重的LOCA条件下导致氢爆炸的覆层型反应的风险。这项研究的大部分集中在于在严重的LOCA条件下施加保护性涂层，以降低其与蒸汽的反应性，或者用在事故中不会对氧化锆取代的含量不会如此危险。不幸的是，当前的涂料和更换套件不足以承受没有明显降解的地方。由于加拿大现在准备建立新的SMR，因此在ATF覆盖中建立专业知识具有相当大的价值，以与其他领先国家（例如美国，法国和中国）相匹配。这些知识对于政府的决策和监管监督以及对SMR建设和运营的许可将特别有价值。欧洲议会最近要求所有反应堆都实施由其各自的国家监管机构批准的ATF，以便有资格为“绿色能源”来源。在加拿大实施此类政策和监管决策将需要对与ATF覆层绩效相关的各种因素有牢固的国内理解，该因素是通过研究现有的ATF覆层概念并开发新颖的加拿大解决方案来确定的。该研究计划旨在开发新颖的ATF覆层，并对现有的ATF覆层概念进行基本研究，以消除严重的LOCA期间氢爆炸的潜力。