Development of Neutron Energy Spectral Signatures for Passive Monitoring of Spent Nuclear Fuels in Dry Cask Storage

Journal Article · Wed Jan 10 00:00:00 EST 2018 · EPJ Web of Conferences

DOI:https://doi.org/10.1051/epjconf/201817007004· OSTI ID:1479969

Harkness, Ira ^[1]; Zhu, Ting ^[1]; Liang, Yinong ^[1]; Rauch, Eric ^[1]; Enqvist, Andreas ^[1]; Jordan, Kelly A. ^[1]

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1. Univ. of Florida, Gainesville, FL (United States). Dept. of Materials Science and Engineering

Demand for spent nuclear fuel dry casks as an interim storage solution has increased globally and the IAEA has expressed a need for robust safeguards and verification technologies for ensuring the continuity of knowledge and the integrity of radioactive materials inside spent fuel casks. Existing research has been focusing on “fingerprinting” casks based on count rate statistics to represent radiation emission signatures. The current research aims to expand to include neutron energy spectral information as part of the fuel characteristics. First, spent fuel composition data are taken from the Next Generation Safeguards Initiative Spent Fuel Libraries, representative for Westinghouse 17^x17 PWR assemblies. The ORIGEN-S code then calculates the spontaneous fission and (α,n) emissions for individual fuel rods, followed by detailed MCNP simulations of neutrons transported through the fuel assemblies. A comprehensive database of neutron energy spectral profiles is to be constructed, with different enrichment, burn-up, and cooling time conditions. The end goal is to utilize the computational spent fuel library, predictive algorithm, and a pressurized ⁴He scintillator to verify the spent fuel assemblies inside a cask. This work identifies neutron spectral signatures that correlate with the cooling time of spent fuel. Both the total and relative contributions from spontaneous fission and (α,n) change noticeably with respect to cooling time, due to the relatively short half-life (18 years) of the major neutron source ²⁴⁴Cm. Identification of this and other neutron spectral signatures allows the characterization of spent nuclear fuels in dry cask storage.

• Research Organization: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE Office of Nuclear Energy (NE)
• Grant/Contract Number: AC52-06NA25396
• OSTI ID: 1479969
• Report Number(s): LA-UR-18-29480
• Journal Information: EPJ Web of Conferences, Vol. 170; ISSN 2100-014X
• Publisher: EDP Sciences
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
spent fuel
safeguards
neutron measurement