Dr
Claire Corkhill
(NucleUS Immobilisation Science Laboratory, University of Sheffield,)
31/10/2017, 11:00
National and international collaborative waste management programs
Oral Presentation
Under the generic scenario envisaged for the geological disposal of vitrified UK high- and intermediate-level waste glass (HLW and ILW, respectively), high pH environments, formed through degradation of the cementitious engineered barrier, are expected to dominate the ground water chemistry thousands of years into the future. We highlight the main findings of a number of recent and ongoing...
Mr
Sean Barlow
(University of Sheffield)
31/10/2017, 11:30
National and international collaborative waste management programs
Oral Presentation
Vitrification of sludge waste arising from legacy nuclear activities such as Magnox reprocessing is a promising alternative to the current baseline plan of cementation with superior long-term durability, improved waste loadings and significant volume reduction. Glass products were produced from oxidized and metallic uranium and magnesium, representative of the extremes found with the First...
Mr
Jarrod Crum
(PNNL)
31/10/2017, 11:45
National and international collaborative waste management programs
Oral Presentation
A borosilicate glass-ceramic waste form is being developed to significantly increase waste loading of high-level waste relative to single phase glass. The glass-ceramic waste form is comprised of approximately 70% borosilicate glass, 20% oxyapatite (X2Ln8Si6O26), and 10% powellite (XMoO4), by mass, where X = alkaline earth and Ln = lanthanides. Understanding the overall corrosion behavior of...
Prof.
John McCloy
(Washington State University)
31/10/2017, 12:00
National and international collaborative waste management programs
Oral Presentation
Owing to high concentrations of Al2O3 from dissolved fuel cladding and Na2O from basification of the waste, about half of the high-level waste by volume at Hanford, Washington, USA is rich in both Na and Al. Formulations of high waste-loading glasses result in lower amounts of SiO2, which often leads to undesirable precipitation of nepheline (NaAlSiO4). Nepheline crystallization can be...
Ms
Amber Mason
(University of Sheffield)
31/10/2017, 13:45
National and international collaborative waste management programs
Oral Presentation
UK stocks of separated civil plutonium are projected to exceed 140 tons at the end of reprocessing. This material may require immobilisation in a proliferation resistant wasteform, should it prove uneconomic to recycle in MOX fuel. We have investigated and optimised alkali tin silicate glass compositions for the immobilisation of this stockpile using CeO2 as a PuO2 surrogate. A remarkable...
Mr
Rui Guo
(University of Cambridge)
31/10/2017, 14:00
National and international collaborative waste management programs
Oral Presentation
The magnesium content of UK Magnox waste glass makes its aqueous durability much poorer than glasses such as SON68, which does not contain Mg. The glass dissolution kinetics is ultimately dependent on the composition/structures of the altered layers(1), here we try to elucidate formation mechanisms.
Alteration layers formed by in-situ precipitation have been discussed widely(2,3), but any...
Mr
Atsushi Mukunoki
(JGC Corporation)
31/10/2017, 14:15
National and international collaborative waste management programs
Oral Presentation
Lead borate glass vitrified at a low temperature is regarded as one of the promising immobilization materials of Iodine-129 which will be removed from a spent AgI filter generated from reprocessing plants and may cause significant effect onto long term safety of geological disposal.
Immersion tests in various solutions have been conducted to understand glass dissolution behaviors in possible...
Dr
Clive Brigden
(ISL, Department of Materials Science & Engineering, University of Sheffield, S1 3JD, UK.)
31/10/2017, 14:30
National and international collaborative waste management programs
Oral Presentation
A study to develop a new high level waste (HLW) glass formulation for waste from the highly active liquor storage (HAL) tanks at Sellafield is described. A likely washout scenario for the tanks at the end of operations involves the use of sodium carbonate as a tank washout reagent [1] leading to a high soda wastestream. Titanium is not currently used in existing HLW formulations in European...
