Characterising legacy spent nuclear fuel pond materials using microfocus X-ray absorption spectroscopy

JOURNAL OF HAZARDOUS MATERIALS

卷:317

Article

Bower, W. R.^1,2,5  Morris, K.¹  Mosselmans, J. F. W.³  Thompson, O. R.²  Banford, A. W.^2,4  Law, K.⁵  Pattrick, R. A. D.¹ 

[1] Univ Manchester, Sch Earth & Environm Sci, Res Ctr Radwaste Disposal, Oxford Rd, Manchester M13 9PL, Lancs, England

[2] Natl Nucl Lab, Chadwick House,Warrington Rd,Birchwood Pk, Warrington WA3 6AE, Cheshire, England

[3] Diamond Light Source, Harwell Sci & Innovat Campus, Didcot OX11 0DE, Oxon, England

[4] Univ Manchester, Sch Chem Engn & Analyt Sci, Oxford Rd, Oxford M13 9PL, England

[5] Univ Manchester, Ctr Radiochem Res, Chem Bldg,Brunswick St, Manchester M13 9PL, Lancs, England

关键词: Concrete;    Decommissioning;    Legacy materials;    Spent fuel pond;    Contamination;    Microfocus spectroscopy;    X-ray absorption;   

DOI  :  10.1016/j.jhazmat.2016.05.037

来源: Elsevier

【 摘 要 】

Analysis of a radioactive, coated concrete core from the decommissioned, spent nuclear fuel cooling pond at the Hunterston-A nuclear site (UK) has provided a unique opportunity to study radionuclides within a real-world system. The core, obtained from a dividing wall and sampled at the fill level of the pond, exhibited radioactivity (dominantly Cs-137 and Sr-90) heterogeneously distributed across both painted faces. Chemical analysis of the core was undertaken using microfocus spectroscopy at Diamond Light Source, UK. Mapping of Sr across the surface coatings using microfocus X-ray fluorescence (pARF) combined with X-ray absorption spectroscopy showed that Sr was bound to TiO2 particles in the paint layers, suggesting an association between TiO2 and radiostrontium. Stable Sr and Cs sorption experiments using concrete coupons were also undertaken to assess their interactions with the bulk concrete in case of a breach in the coating layers. mu XRF and scanning electron microscopy showed that Sr was immobilized by the cement phases, whilst at the elevated experimental concentrations, Cs was associated with clay minerals in the aggregates. This study provides a crucial insight into poorly understood infrastructural contamination in complex systems and is directly applicable to the UK's nuclear decommissioning efforts. (C) 2016 The Authors. Published by Elsevier B.V.

【 授权许可】

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