Radiolytic hydrogen production in heterogenous systems with plant relevance: Generic computational and experimental models.

各种模型系统，无论是计算的还是实验的，都被用来在工厂中固定与氢有关的安全案例。退役和钚管理面临的主要挑战之一是异质系统中氢的辐射分解产生。对于退役，这涉及到在污泥中产生放射性裂解氢，例如在Magnox池塘中和在离子交换树脂中。对于钚的管理来说，关键问题是氢的积累，据信这是由于经历阿尔法辐射分解的薄水层产生的氢可以对储存罐施加压力。我们将统一实验和模拟方法，提供它们之间的近实时比较。将为污泥、胶体和湿/干粉开发一个顺序辐射分解制氢实验和比较器模拟的框架。在实验中，需要在计算机控制下改变的参数包括液体组成(包括pH值)、头部/溶解气体环境和温度。除了允许我们模拟预期的顶空/溶解气体成分和年龄样本之外，我们还将能够对系统进行编程，以在一系列与植物安全活动相关的情况下研究氢的辐射分解产生和重新组合，范围从“纯”参数确定实验(例如G值)到能够探测辐射分解产生和氢的去除以及相关界面化学变化的复杂相互作用的实验。将扩展并行计算框架以对预期行为进行比较器模拟。它将能够模拟连续的实验，然后便于对工厂规模的池塘储存和钚管理问题进行有意义的外推。总而言之，将我们的模拟和建模研究流结合在一起，这个项目的学生将进行一系列示范实验和比较模拟，研究氢气生产在以下方面的影响：i)pH值的变化，溶解气体以及对胶体和污泥(如水镁石和离子交换树脂)的辐射/化学老化；ii)水层厚度，氢/氧顶空气体组成，氯污染和PuO2模拟器上的辐射/化学老化。这种双重结构和方法的另一个好处是它带来了Marcus Webb博士的专业知识，我们正在提议的数值方法方面的领先专家，这可能是该行业面临的许多模拟问题的关键。由于它与核工业相关，因此该项目涉及EPSRC能源/脱碳的优先领域

Various model systems, both computational and experimental, are used to under-pin hydrogen-related safety cases on plant. One of the major challenges for both decommissioning and plutonium stewardship concerns the radiolytic generation of hydrogen in heterogenous systems. For decommissioning this relates to the radio-lytic production of hydrogen in sludges, e.g. in magnox ponds, and in ion exchange resins. For plutonium stewardship the key issue is the build-up of hydrogen, believed to be due to the thin layers of water undergoing alpha radiolysis creating hydrogen which can pressurise the storage cans.We will unify experimental and simulation approaches providing near-real time comparison between them. A framework for sequential radiolytic hydrogen generation experiments and comparator simulations will be developed for sludges, colloids and wet/dry powders. In experiment, parameters to be varied under computer control include liquid composition (inc pH), head/dissolved gas environment and temperature. As well as al-lowing us to simulate expected headspace/dissolved gas compositions and age samples, we will be able to program the system to investigate the radiolytic generation and recombination of hydrogen across a range of situations relevant to plant safety activity ranging from 'pure' parameter determination experiments (e.g. G-values) to experiments able to probe the complex interplay of radiolytic production and removal of hydrogen alongside changes in the relevant interfacial chemistry.A parallel computational framework will be extended to make comparator simulations of the expected behaviour. It will be able to simulate the sequential experiments and then facilitate meaningful extrapolation to plant-scale pond-storage and plutonium stewardship problems.Drawing together our simulation and modelling research streams, in summary the student in this project will Perform a series of exemplar experiments and comparator simulations, studying effects of hydrogen production on: i) change of pH, dissolved gas and radiation/chemical aging on colloids and sludges such as brucite and ion exchange resins and ii) ii) water layer thickness, hydrogen/oxygen headspace gas composition, chlorine contamination and radiation/chemical aging on PuO2 simulants.An additional benefit of this dual strand approach is that it brings expertise of Dr Marcus Webb, a leading expert in the numerical methodology we are proposing, and which could be key to many simulation problems the industry faces.Due to its relevance to the nuclear industry this project relates to the EPSRC priority area of Energy/Decarbonisation