The use of reprocessed uranium in light water reactors: Problem identification and solution finding

Of the three main options available to the utility Energie Baden-Wuerttemberg (EnBW) for the use of reprocessed uranium (RepU) to produce enriched uranium for the manufacturing of nuclear fuel assemblies (FA) two have been used: the re-enrichment by centrifuges and blending with high-enriched uranium. The decision was influenced by commercial and technical conditions. Following the reasons also mentioned in Chapter 4.1.2.5 of IAEA-TECDOC-1529 [1] the use of RepU as matrix for (mixed oxide) MOX FA was not considered, the main argument being the intention to use as much as possible plutonium per FA due to the high MOX fabrication costs compared with Unat or enriched reprocessed uranium (ERUa) fuel fabrication. The isotopic composition of natural uranium (Unat) and RepU, the description of the corresponding isotopes as well as the various recycling possibilities are detailed extensively in the document IAEA-TECDOC-1529 of February 2007. (author)