A review of contamination of metallic surfaces within aqueous nuclear waste streams

• Published in: Progress in nuclear energy (New series) 2023-05, Vol.159, p.104637, Article 104637
• Main Authors: Barton, Daniel N.T., Johnson, Thomas, Callow, Anne, Carey, Thomas, Bibby, Sarah E., Watson, Simon, Engelberg, Dirk L., Sharrad, Clint A.
• Format: Article
• Language: English
• Subjects: Aqueous nuclear waste streams; Contamination mechanisms; Corrosion; Decontamination; Metallic surfaces; Nuclear decommissioning; Stainless steel
• ISSN: 0149-1970
• DOI: 10.1016/j.pnucene.2023.104637

Metallic plant infrastructure (e.g. pipework, vessels and structural materials) is often subjected to extreme environments within nuclear facilities such as acidic spent fuel reprocessing and fuel storage ponds. Exposed surfaces can become contaminated with a wide range of radioactive contaminants, including high yield fission products and actinides. Identification of the mechanisms by which radionuclides interact with metallic surfaces, such as stainless steel, is a crucial factor during decontamination strategy development. Once contamination mechanisms are fully understood, careful selection of tailored decontamination approaches will lead to both primary and secondary waste volume reduction, subsequently reducing the economic and environmental burdens associated with disposal, allowing for recycling or re-use of the material. This review of the literature provides a summary of work accumulated in the field of radionuclide contamination of stainless steel surfaces. Trends with respect to contamination mechanisms, as well as the factors contributing to contamination such as surface chemistry and corrosion, are presented. The outstanding research needs to further develop our understanding of contamination mechanisms have been identified, including the advanced materials characterisation techniques likely to play a significant role in contaminant identification. [Display omitted] •Understanding how metal surfaces are contaminated is essential to decommissioning.•Contamination influenced significantly by solution and material properties.•Mechanisms include electrostatic interactions, co-precipitation and bulk diffusion.•Tailored decontamination approaches can subsequently be developed.