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To mitigate the waste created by conventional fission reactors, spent nuclear fuel must be mechanically separated from its cladding. For the development of fuel processing technology to support the Advanced Accelerator Applications (AAA) Program, aqueous and pyrochemical processes will be used to further separate technetium and iodine, uranium and the higher actinides (see Figure 1 for an example of the process layout)1. The higher actinides, including plutonium, americium, curium, and neptunium will be separated from the waste to facilitate their fabrication into new fuel for placement in a transmuter. High-energy neutrons generated by spallation in the transmuter break down these actinides and long-lived fission products through activation and fission to produce stable elements or radionuclides with short half lives.

During the separation process, concentrated quantities of fissionable plutonium and americium pose a potential nuclear criticality risk. At each stage in the process, an assessment of the effective neutron multiplication factor, keff, will be necessary to prevent the possibility of sustained fission. We propose to perform nuclear criticality analyses in support of the development of fuel separation processes for AAA.


Actinide elements – Separation; Criticality (Nuclear engineering); Nuclear fuel claddings; Radioactive substances – Separation; Separation (Technology); Transmutation (Chemistry); Transuranium elements – Separation


Chemistry | Nuclear | Nuclear Engineering | Oil, Gas, and Energy