Design, build and test of helium ion and gamma irradiation flow loop

Summary: This project investigates the radiation stability of advanced spent nuclear fuel separation processes under industrially relevant conditions. Fundamental knowledge on the effect of radiation on separations processes is necessary in order to underpin the performance and viability of processes at an industrial reprocessing plant scale. The ability to gather this information in the UK is limited to a few institutions and techniques are limited to simple experimental arrangements that do not adequately incorporate the nuances of intimate mixing that occurs in real separations processes. However, recent studies show that mixed biphasic systems show differences in the radiation stability compared with irradiation of the separate phases or static mixtures.

Scope of the project: This PhD project will develop a modular irradiation test loop that can be used for both gamma and helium ion irradiations of mixed phase systems (will fit both inside common irradiator types and have a window suitable for use on beamline end stations). The project involves designing, building and testing a bespoke new UK capability with suitable, versatile online sampling and analytical capabilities. The final system will contain all the normal facets of a solvent extraction system; settling/separation tanks, temperature control, mixing regions and a flow loop. The project will then move on to an experimental programme of irradiating and testing systems designed and developed both in the UK and internationally, providing data on the radiation tolerance, changes to the physicochemical properties and use within the process.

Expected Impact:
- New unique UK capability that will also provide a basis for future collaborations nationally and internationally;
- Data to be used to underpin next generation solvent extraction processes and particularly:
- To assess the validity of previous static irradiation experiments. The results will contribute to high quality research publications;
- The determination of the dose limit where aqueous processes are no longer viable and molten salt techniques may be required;
- Continue to revitalize radiation chemistry in extraction processes in the UK:
- The PhD builds on previous ARIS-funded and AFCP research undertaken at Dalton Cumbrian Facility (DCF);
- The PhD will contribute to and benefit from the ongoing activities in DCF aimed at design and development of Simple MOdular Radiation Experimental Systems (SMORES);
- Demonstrable UK's capability on international stage with respect to radiation effects in solvent extraction;
- Increase UK's knowledge around online monitoring of gas and liquid production in nuclear processes