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DISTINCTIVE is a multi-disciplinary collaboration of 10 universities and 3 key industry partners from across the UK’s civil nuclear sector.

Active Research Fund

Date: February 23, 2016

At the time of submitting a proposal to the EPSRC, a number of PDRA projects indicated a potential need for active research facilities; however, a detailed understanding of facility needs and the duration of work was unable to be defined. As a result, an Active Research Fund (ARF) was requested.

In total, £288k was awarded to the consortium as part of the DISTINCTIVE grant (EP/L014041/1) to facilitate active research, including international secondments and small equipment purchases.
An ARF Call is announced every six months, and our PDRAs are asked to submit a proposal outlining how the funding will be used and how the sub-project will support the strategic aims of the consortium.
All proposals are reviewed by the programme’s Management Board. The review is chaired by Prof. Simon Pimblott (University of Manchester) who is the cross-cutting champion in this area. He has the responsibility to promote the use of active facilities and to ensure that the consortium receives excellent advice and support , especially relating to technical needs and duration of work.
So far, we have held two calls, one in January 2015 and one in July 2015. To-date, five sub-projects have been supported. Here the successful candidates summarise the proposed work:
Round 1
Investigation of Silica Grout-radionuclide Interactions: Impact on Radionuclide Mobility and Silica Gelation
Dr. Matteo Pedrotti – University of Strathclyde

One of the main objects of the DISTINCTIVE Work Package 4 is to develop in-situ ground barriers that could act as a ‘second skin’ surrounding on-site structures for prevention of subsurface radionuclide migration using silica based grouts. Silica grouts will be injected into contaminated areas. Therefore it is crucial that the silica-radionuclides interactions are well understand to ensure that the silica grout does not increase radionuclide mobility and that, ultimately, it reduces the hydraulic permeability, in the presence of radionuclides, down to values of ~10-9 m/s, thus preventing radionuclide migration. The two aims for this active sub-project are:
(1) To determine the effect of radionuclides on silica gelation and changes to hydraulic conductivity of soil.
– The presence of radionuclides may prevent, accelerate or retard the gelation of silica and therefore affect the final permeability of the grouted soil.
(2) To determine the effect of colloidal siica injection and gelation on radionuclide speciation and mobility
– Interactions of silica colloids with sorbed radionuclides may cause desorption of the radioisotope from soils in situ and hence increase radionuclide mobility
– Increases in groundwater flow through injection of the silica grout may enhance radionuclide mobility.

The Corrosion of Spent Nuclear Fuel
Dr. Leila Costelle – University of Bristol
In the present project, we synthesise thin film samples of uranium dioxide-based materials and expose their surfaces to a range of chemical conditions and radiation fields in order to closely mimic the environments expected to be found at the surface of spent nuclear fuel (SNF). This is of great importance as we currently rely on calculations of these processes to predict the mid- and long-term effects of our nuclear waste containment strategies. We use a range of techniques in order to probe the dynamic changes to the fuel’s structural integrity and to measure the dissolution products. This combination of modern synthesis techniques, characterisation and cutting-edge large facilities research, will have significant impact on our understanding of SFN behaviour during storage and disposal, and the arising experimental results will be used as important parametric input for calculations of the likely long-term degradation of SNF in variety of potential storage and disposal scenarios.

An Investigation of Wasteform Evolution During Wet-recovery and Drying of SNF
Dr. James Darnbrough – University of Bristol
Bristol’s application for Active Research Fund is based around the key issue for nuclear fuels of thermal conductivity. The question of how easily a material can dissipate heat has implications throughout the fuel cycle. This ranges from the efficiency of the fuel at heating water, making steam which turns the turbines producing electricity, to accident tolerance, what happens when cooling is lost, and to how the material acts after life in a reactor, how is it safe to store or dispose.

Therefore funds were sort to create a simple device to measure the thermal conductivity of samples produced to mimic the fuel at different stages throughout life and focusing on spent fuel to help inform safe long term geological storage. This information will elucidate some of the key challenges in the nuclear industry and indicate a root towards a safe treatment of future and legacy fuels.
Round 2
Building a Portable Ultra-high Vacuum (UHV) Chamber for Active Samples
Dr. Leila Costelle – University of Bristol
The aim of this project is to build a portable sample storage device with ultra-high and inert gas overpressure and suitcase capabilities. The system will allow us to transfer active samples between different equipment and transport to beam lines, without getting them exposed to ambient conditions.

Fission Product Effects on Spent Fuel Corrosion
Dr. James Darnbrough – University of Bristol
This project will be the next step, building on work conducted on pristine samples, to interrogate the reactions happening at the surface of nuclear fuel after life in the reactor. During the time in the reactor the fuel undergoes many changes through radiation damage and fission reactions. The range and amounts of fission products are well understood; however, the effect of these daughter products on the dissolution and reactions at the surfaces of spent nuclear fuels requires investigation for the considerations required when dealing with safe long-term storage.
In using a de novo approach to researching this problem, we are able to engineer a simulation sample with complete control over the structure (through growth at Bristol), contamination/implantation (through work at the Surrey University Ion Beam Centre) and radiation field (through synchrotron flux X-rays at Diamond). This allows investigation into potential corrosion and other key factors for long-term storage with a system that is controlled and safe to give results that can inform solutions to real problems.
The DISTINCTIVE University Consortium gratefully acknowledges funding from the EPSRC as part of the Research Councils UK Energy programme.
The Energy Programme is a Research Councils UK cross council initiative led by EPSRC and contributed to by ESRC, NERC, BBSRC and STFC

 

Dr. Pedrotti’s PDRA project is titled “ In-situ Ground Contaminant Containment (Physical Barrier)”. His lead supervisor is Dr. Grainne El Mountassir (grainne.elmountassir@strath.ac.uk).

Dr. Costelle and Dr. Darnbrough’s PDRA project is titled “An Investigation of Wasteform Evolution During Wet-recovery and Drying of SNF”. Their lead supervisor is Dr. Ross Springell (phrss@bristol.ac.uk).

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