LWR spent fuel characterisation by non-destructive assay
Within the Nuclear Waste Programme at the Institute for Transuranium Elements, non-destructive assay (NDA) is being developed for the characterisation of individual spent fuel pins. The aim of spent fuel characterisation is twofold: (i) to verify the declared burnup and determine its axial distribution; (ii) to determine the radiotoxicity content of the fuel in relation to leaching studies, having in view the option of the direct disposal of spent fuel. The spent fuel is characterised inside a hot cell by passive neutron interrogation and isotopic correlations. Passive neutron interrogation is performed by an array of neutron detectors embedded in a polyethylene moderator. The counting unit is installed inside a beta-gamma hot cell and rests on a metrology bench. The nuclear electronic modules are situated outside the cell and the whole procedure is controlled by a PC. The required information is obtained as a function of a distance along the fuel length. Following the non-destructive measurement of the neutron emission coming from spontaneous fission of the fuel, isotopic correlations - calculated using the computer code KORIGEN - were used to extrapolate information needed for the characterisation. Segments of the fuel already analysed non-destructively were dissolved for subsequent analysis by IDMS for calibration of the NDA method.
Bibliographic Reference: Paper presented: International Symposium on Geological Disposal of Spent Fuel, Antwerpen (NL), October 19-23, 1992
Availability: Available from (1) as Paper EN 36847 ORA
Record Number: 199211376 / Last updated on: 1994-11-29
Original language: en
Available languages: en