Advanced Waste Management Strategies for High Dose Spent Adsorbents

Lead Research Organisation: Imperial College London
Department Name: Materials

Abstract

The Great East Japan Earthquake, on 11 March 2011, triggered a devastating tsunami, leading to the loss of at least 19,000 lives and partial melt down of three boiling water reactors at the Fukushima Dai-ici site (Units 1-3). A key technology need in the site stabilisation, recovery and decommissioning programme at the Fukushima Dai-ici site is the decontamination of water used to cool the damaged reactor cores and ground water infiltrating the damaged reactor buildings. This is achieved by use of commercial inorganic ion exchange materials to strip the radionuclide contaminants in several purpose built facilities, which yield a variety of highly radioactive and dispersible "High Dose Spent Adsorbents". Of key concern is the production of hydrogen from radiation induced degradation of water within the adsorbent material, which poses an explosive hazard. The overarching aim of this project is to improve the passive safety of the high dose spent adsorbents to assure prolonged near surface storage and / or disposal in an engineered facility, in accordance with IAEA Safety Standards for the storage and pre-disposal management of radioactive wastes. To achieve this goal, we will develop novel thermal treatment approaches to transform the wet, granular, and dispersible material into an immobile monolithic form which is chemically and physically stable, eliminating the key hazard of hydrogen production. The approaches developed in this project will address a common need in international decommissioning and civil nuclear energy programmes, in which inorganic ion exchange materials find common application. In particular, the research will provide a route to treat a substantial volume of clinoptilolite waste present on the Sellafield site (classed as intermediate level waste) for which there is no currently accepted treatment route.
 
Description Working with colleagues at Sheffield University and Kyushu and Tohoku universities in Japan we are developing wasteforms to immobilise the zeolite adsorbents being used to clean contaminated water at Fukushima. Various systems are being examined including borate and borosilicate glasses. We determined that zeolitic adsorbents can be successfully encapsulated within Pb based glasses with very low processing temperatures and that combined analytical decay codes and Monte-Carlo radiation transport modelling can be used to calculate the heat output of compositionally diverse nuclear wasteforms.
Exploitation Route This may help in future where water is contaminated with radionuclides including UK locations.
Sectors Energy,Environment

 
Description The work was concerned with the development of wasteforms for the immobilisation of adsorbents used in effluent water treatment as part of the clean-up following the Fukushima-Daiichi accident. During use these adsorbents become contaminated with highly active but relatively short lived radionuclides. As part of this project, inventory calculations were conducted allowing the decay of these nuclides to be predicted and consequently the compositional changes experienced by the waste over its life. These supported the choices made in the experimental component of the work. The decay studies demonstrated that the activity and heat output of the waste diminished over a sufficiently short timespan that it became reasonable for the wasteform to be stored in an actively monitored surface facility for the most challenging part of its life. This supported the experimental decision to design wasteforms that emphasised low processing temperature over outright durability. Therefore, a useful result of the work is to demonstrate how such modelling predictions can be used to justify an experimental programme of work. Perhaps more importantly, the development of wasteforms with lower processing temperatures, now provided the opportunity to minimise the potential release of radioactive Cs-137 into the environment. This grant was also important in furthering collaboration between institutions both within the UK and abroad. Three different wasteform concepts were developed for the project. These showed quite different approaches to solving the same problem. This led to a spirit of friendly competition between the Imperial, Sheffield and our collaborators in Japan. The effect of this was to strengthen collaborative links and to improve the scientific rigour of the work produced.
First Year Of Impact 2017
Sector Energy,Environment
 
Description A new precision cutting saw for radiological materials science
Amount £10,990 (GBP)
Organisation University of Sheffield 
Sector Academic/University
Country United Kingdom
Start 04/2016 
End 03/2017
 
Description DECC - MIDAS capital grant
Amount £800,000 (GBP)
Organisation Department of Energy and Climate Change 
Sector Public
Country United Kingdom
Start 04/2015 
End 03/2016
 
Description EPSRC UK-Japan Nuclear Research Call - Advanced Waste Management Strategies for High Dose Spent Absorbents
Amount £435,120 (GBP)
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 11/2015 
End 03/2018
 
Description UoS & Suppliers - MIDAS equipment match
Amount £335,000 (GBP)
Organisation University of Sheffield 
Sector Academic/University
Country United Kingdom
Start 04/2015 
End 03/2016
 
Description Collaboration with ESRF XMAS and DUBBLE beamlines 
Organisation European Synchrotron Radiation Facility
Country France 
Sector Charity/Non Profit 
PI Contribution Extended application focus of beamline techniques to XAS data acquistion in the hard X-ray regime.
Collaborator Contribution Beamline optimisation to acquire XAS data from glass and ceramic materials in support of plutonium disposition.
Impact See publications section.
Start Year 2016
 
Description Collaboration with Kyushu University 
Organisation Kyushu University
Department Department of Applied Quantum Physics and Nuclear Engineering
Country Japan 
Sector Academic/University 
PI Contribution Glass formulation design and characterisation for conditioning of high dose spent adsorbents at the Fukushima site.
Collaborator Contribution Formulation and characterisation of hot isostatically pressed ceramic wasteforms for high dose spent adsorbents at the Fukushima site.
Impact See research publications.
Start Year 2015
 
Description Collaboration with Tohoku University 
Organisation Tohoku University
Country Japan 
Sector Academic/University 
PI Contribution Glass formulation design and characterisation for conditioning of high dose spent adsorbents at the Fukushima site.
Collaborator Contribution Formulation and characterisation of hot isostatically pressed ceramic wasteforms for high dose spent adsorbents at the Fukushima site.
Impact See publications section.
Start Year 2015
 
Description Dimitri Pletser Hitachi Secondment 
Organisation Hitachi
Country Japan 
Sector Private 
PI Contribution Study of Cs and Sr volatilisation from simulant spent adsorbents during processing to glass composite material wasteform.
Collaborator Contribution Use of facilities and expertise.
Impact Due to start in July 2016.
Start Year 2016
 
Title Radioactive Heating Tool 
Description A key output of the work was the development of a heating prediction tool. This is a piece of software was developed during the work based around CERN's GEANT-IV radiation transport toolkit. The tool has been designed to be flexible enough to allow accurate heating predictions to be made for arbitrary wasteform compositions and waste package shapes. 
Type Of Technology Software 
Year Produced 2017 
Impact It is hoped that the heating tool will find application beyond the current project. To this end work is ongoing to allow its public release. The intention of this is to provide a useful design tool that can help in the optimisation of parameters such as waste-loading and waste package shape and size. Ultimately this will support cost reduction in nuclear waste disposal by providing scientists and engineers the information they need to make better use of the space inside any expensive geological disposal facility that is constructed. 
 
Description Collaboration building seminar on thermal treatment of radioactive wastes with leading researchers from Japan 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Research seminar involving ca. 30 leading researchers from Japan and University of Sheffield to explore opportunities for collaboration in thermal treatment of radioactive wastes.
Year(s) Of Engagement Activity 2016
 
Description Feature article on Fukushima and Chernobyl related research sponsored by EPSRC 
Form Of Engagement Activity A magazine, newsletter or online publication
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact Feature interview in Sheffield Star and Sheffield Telegraph on radioactive waste management research, with particular focus on applications at Chernobyl and Fukushima.
Year(s) Of Engagement Activity 2017
URL http://www.sheffieldtelegraph.co.uk/news/star-interview-with-richard-blackledge-how-sheffield-expert...
 
Description MRS Scientific Basis for Nuclear Waste Management XL 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Organised flagship 40th anniversary MRS symposium on scientific basis for nuclear waste management, showcasing research in multiple EPSRC sponsored projects.
Year(s) Of Engagement Activity 2017
 
Description Radio interview on Fukushima decommissioning and our related research 
Form Of Engagement Activity A broadcast e.g. TV/radio/film/podcast (other than news/press)
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Radio interview on Fukushima decommissioning and our related EPSRC sponsored research.
Year(s) Of Engagement Activity 2016
URL https://sputniknews.com/radio_world_in_focus/201703061051319142-hollande-le-pen-turkey-syrian-kurds-...
 
Description Sheffield scientists pioneer new method for managing radioactive waste 
Form Of Engagement Activity A broadcast e.g. TV/radio/film/podcast (other than news/press)
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact Television interview as part of World Science day, discussing radioactive waste management research associated with EPSRC sponsored projects.
Year(s) Of Engagement Activity 2017
URL https://vimeo.com/191056195
 
Description UK-Japan Phase 2: Wasteforms for Fukushima-Daiichi High Dose Spent Adsorbents", EPSRC - Foreign and Commonwealth Office UK-Japan Networking Event, 26th March 2017, Japan Science and Technology Agency, Tokyo, Japan 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Presentation summarising the activity conducted for the grant given to academics and government officials in Tokyo. The event was designed to encourage networking between UK and Japanese academics in order to promote new research collaborations in nuclear research. New links were made between the researchers on this project and new academic contacts both in Japan and also at UK universities.
Year(s) Of Engagement Activity 2017