PACIFIC - Providing a Nuclear Fuel Cycle in the UK for Implementing Carbon Reductions

太平洋学院是一个多学科项目，覆盖英国12所大学，支持英国未来的核燃料循环。我们的目标是在现有和先进核燃料的制造、性能和回收方面提供世界级的相关研究计划。在英国的一项重大学术研究计划中，我们将首次将核燃料和分离技术这两个主题整合到一个具有共同目标的单一计划中。在燃料专题中，我们的目标是为了解核燃料和覆层材料在其整个使用寿命和储存期间发生的损害机制提供科学和技术基础。我们的目标是：1.扩展分子动力学模型以预测先进燃料的关键性质；2.确定有前景的先进燃料的单组分和复合材料，并开发适当的制造路线；3.通过采用双碳化硅/锆层来研究改进Triso包覆燃料颗粒的可能性；4.评估先进燃料和涂层在一系列条件下的性能；以及5.研究轻水堆中颗粒-包层相互作用失效的机理。第一个燃料项目研究先进燃料和涂层。该项目将采用先进的建模和实验技术相结合的方法，以确定有前景的新燃料材料，并探索现有和先进燃料材料，包括包覆燃料颗粒的辐射损害的机制和影响。具体任务包括：-燃料建模-先进的燃料制造-先进的三元涂层燃料颗粒-材料特性和辐射第二个燃料项目涉及一种称为颗粒-包层相互作用(PCI)的故障机制。这个项目将集中于通过将冶金、机械工程、化学和辐射方面结合起来，通过实验研究相结合，并以计算机模拟为基础，从机理上对PCI进行理解。在分离主题中，这些项目旨在为能够从热燃料原料中提供适合快堆燃料的产品的综合流程图提供概念证明。我们的目标是：1.证明U、Pu和Mas可以分离到所需的纯度，并在混合产品中转化为快堆燃料。证明湿法冶金分离过程中的液体产物可以转化为快堆燃料制造所需的形式。证明了一种新的湿法分离工艺可以在现有的溶剂萃取技术下运行。证明可利用的新技术将提供比目前的溶剂萃取技术更好的效果。关于次要榄系元素分离的项目将研究新的疏水萃取剂，用于从镧系元素中分离MA、族榄系元素分离和Am/Cm分离。具体的任务包括：-直接监测次铟分离中的形态--优化分离过程中的界面转移动力学--分离中的鳗行为和络合剂的辐解效应--配基结构-活性关系开发高级分离技术项目包括以下任务：-更好地了解传统的溶剂提取技术--使用强化过程进行高效提取--连续的色层分离任务包括：-建立和优化直接减少乏燃料的流程--去污和固定焚烧废物。

PACIFIC is a multi-discipline programme, across 12 UK universities, that supports a future nuclear fuel cycle in the UK. We aim to provide a world-class programme of relevant research into the manufacture, performance, and recycle of current and advanced nuclear fuels. For the first time in a major UK academic research programme, we will integrate the two Themes of Nuclear Fuel and Separations Technology into a single programme with a common goal. In the Fuels Theme, our aim is to provide a scientific and technological underpinning to understanding the damage mechanisms that occur in nuclear fuel and cladding materials throughout their operational life and during storage. Our objectives are to:1. extend molecular dynamics models to predict key properties of advanced fuels;2. identify promising single component and composite materials for advanced fuels and to develop appropriate manufacturing routes.;3. investigate the potential for improved TRISO coated fuel particles by employing a duel SiC/ZrC layer;4. assess the performance of advanced fuels and coatings under a range of conditions; and5. investigate the mechanism of Pellet-Cladding Interaction failures in LWRs.The first Fuels project addresses advanced fuels and coatings. This Project will employ a combination of advanced modelling and experimental techniques to identify promising new fuel materials, and to explore the mechanisms and effects of radiation damage in both current and advanced fuel materials, including coated fuel particles. Specific Tasks include:- Fuel Modelling- Advanced Fuel Manufacture- Advanced TRISO Coated Fuel Particles- Materials Characterisation and IrradiationThe second Fuels project concerns a failure mechanism known as Pellet-Cladding Interaction (PCI). This project will focus on developing a mechanistic understanding of PCI by bringing together metallurgical, mechanical engineering, chemical and radiation aspects; by a combination of experimental investigations and underpinned by computer simulation.In the Separations theme, the projects aim to provide a proof of concept for an integrated flowsheet capable of providing a product suitable for fast reactor fuels from a thermal fuel feed. Our objectives are to:1. Prove that U, Pu and MAs can be separated to the required purities and in a mixed product for conversion to fast reactor fuel.2. Prove that the liquid product from a hydrometallurgical separation process can be converted to the required form for fast reactor fuel manufacture.3. Prove that a new hydrometallurgical separation process can operate within current solvent extraction technologies.4. Prove that new technologies are available that will offer benefits over current solvent extraction technologies.The project on Minor Actinide Separations will investigate new hydrophobic extractants use in separation of MAs from lanthanides, group actinide separations and Am/Cm separations. Specific Tasks include: - Direct Monitoring of Speciation in Minor Actinide Separations- Optimising Interfacial Transfer Kinetics during Minor Actinide Separations- Actinide Behaviour and Radiolysis Effects of Complexants in Minor Actinide Separations- Ligand Structure-Activity Relationship DevelopmentThe project on Advanced Separations Technology includes the following tasks: - Develop a better understanding of conventional solvent extraction technology - High efficiency extractions using intensified processes- Continuous Chromatographic Separation of Actinides and Fission ProductsThe final project concerns Product Conversion to Fuel, and will develop the fundamental molten salt technology to take the product from a PUREX plant and convert it efficiently through direct reduction to metal, considering proliferation resistance and waste minimisation. Tasks include:- Establishment and optimisation of the process for direct reduction of spent fuel- Decontamination and immobilisation of pyroprocessing wastes.