The PARALLEX Project: Irradiation Testing and PIE of the First Bundle

Abstract

The Parallex Project is a parallel experiment demonstrating the use of U.S. and Russian weapons-derived plutonium (WPu) in CANDU mixed-oxide (MOX) fuel elements. A major component of the Parallex Project is the irradiation testing of MOX fuel elements containing WPu manufactured in both the U.S. and Russia. A total of three fuel bundles were ,manufactured for irradiation testing in the NRU reactor in Chalk River. A significant milestone in the project was achieved earlier this year, with the completion of the irradiation testing of the first fuel bundle containing MOX elements received from both the U.S. and Russia. The MOX fuel elements for the first Parallex bundle were supplied by the Los Alamos National Laborato1y in the U.S. and by the Bochvar Institute in Russia. The MOX fuel pellets with 3.1 % WPu in depleted uranium MOX are contained in the intermediate and inner elements, and the bundle is configured such that the Russian and U.S. elements are tested side-by-side. The MOX fuel elements were assembled into a bundle in Chalk River and the first bundle was inserted into the NRU fuel test loop in February 2001. The bundle was irradiated at midplane linear powers up to 40 kW/m and achieved its target burnup of 15 MWd/kgHE (360 MWh/kgHE) in January 2003. Post-irradiation examination of the fuel has been started to determine the performance of CANDU MOX fuel made from WPu. Irradiation testing of the other two bundles is continuing. This paper highlights the irradiation testing of the first Parallex bundle and presents the results obtained to-date from the post-irradiation examination.