Mathematical Modelling of hydrogen isotope separation and retention behavior during nuclear fusion plant-scale operations

This research sets out to develop on technology for the separation of hydrogen isotopes for the use in fusion reactor active gas handling systems. This involves separating the species of the gas streams leaving the reactor so the useful components can be recycled back to the torus where they can be further reacted. This is of high priority for optimisation for two main reasons; the burn up efficiency is very low within the torus, and tritium is very difficult to obtain in nature. Thus, it is important to create better models of these systems with accurate data to ensure maximum efficiency of the recycle systems. One of the difficulties faced with hydrogen isotope separation is the diatomic nature of the element. This creates 6 isotopologues with extremely similar properties and hence a very difficult separation. This research aims to try and overcome the difficulties in the modelling of these isotopes so it can be accurately determined how they act under certain conditions.

The prime goal is to model efficiently the separation of these isotopes using cryogenic distillation and pressure swing adsorption technologies. This modelling is proposed to be done in two different ways. The first is using ASPEN Plus, which can be used to create models of vast engineering systems and will likely be used to model the entire proposed systems. The second is MOOSE (Multi-Physics Object-Oriented Simulation Environment) which can be used to model small- and large-scale physical phenomena. Building these two models together with the goal of achieving a complete picture of what is going on. Due to the lack of data present for some of the isotopes involved, namely tritium, there is also interest in obtaining real data from JET along with the UKAEA to verify these models. Also, the potential to run experiments at the current cryogenic distillation column at JET, in which tritium is used, to obtain some important tritium related data to further improve the models. This data would be beneficial in many ways, it could improve and verify different models to ensure correct optimisation of the system.

This research has benefits for the small fusion engineering community and for the much larger energy users of the world. For the engineering community, this research allows a window into what is accurately going on within the separation environment and highlights where improvements can be made to the systems or where new technology can be implemented.

For the larger community, it is a small cog in a large group trying to work towards getting fusion to become viable. Fusion holds incredible potential for a clean energy source, which could improve the sustainability of energy production greatly. This research aims to provide some help and understanding into a small area of this grand venture to try and overall combat some of the damage that is caused during energy production via alternative methods.