Characterization of Used CANDU Fuel by Non-Destructive and Destructive Radiochemical Analyses

Abstract

A comprehensive program to analyze used fuel was carried out at the Whiteshell Nuclear Research Establishment (WNRE) as part of a larger study of the long-term behaviour of used CANDU fuel stored in dry and moist air at 150 degrees C. Measurements were carried out to determine fission product and burnup distributions along the length of fuel elements, across radii of fuel bundles, and within individual transverse sections of fuel elements. Destructive radiochemical analyses were used to confirm the gamma-scanning data. The results show significant burnup gradients axially and radially within individual elements and fuel bundles. The analytical results are in good agreement with reactor physics computer code predictions.