Dense and homogeneous MOX fuel pellets manufactured using the freeze granulation route. Issue 5 (20th January 2020)

• Record Type: Journal Article
• Authors: La Lumia, Florian; Ramond, Laure; Pagnoux, Cecile; Coste, Philippe; Lebreton, Florent; Sevilla, Jean‐Robert; Bernard‐Granger, Guillaume
• Is Part Of: Journal of the American Ceramic Society. Volume 103:Issue 5(2020)
• Page Start: 3020
• Page End: 3029
• Publication Date: 2020-01-20
• Subjects: binders/binding -- dispersants/dispersion -- granules -- microstructure -- sinter/sintering; Ceramics -- Periodicals; 620.1405
• DOI: 10.1111/jace.17005
• Languages: English
• ISSNs: 0002-7820

Abstract

Abstract: MOX fuels (UO2 ‐PuO2 ) are used in light water nuclear reactors of several countries and are also potential candidates for the fast neutron reactors. Industrial MOX is currently manufactured by a dry route process, involving steps with fine powders. To reduce dusting, enhance MOX powder flow properties, and decrease manufacturing scrap rate, a new wet route process is investigated: the freeze granulation of concentrated water‐based powder suspensions having optimized rheology and dispersion properties. Highly flowable, dustless, and easy‐to‐press MOX granules have been elaborated. Sintering green compacts made of such granules gives highly dense and defect‐free pellets that have a very homogeneous U‐Pu spatial distribution, thus improving the fuel characteristics. Indeed, MOX fuels devoid of large Pu‐rich aggregates are thought to have a better behavior under irradiation in reactors by limiting/preventing the formation of the typical high burnup structure.