Patent ID: 6764618
Filing Date: 2004-07-20
Classification: G21C,Y02E

Abstract:
A process for manufacturing (U,Pu)O2 mixed oxide nuclear fuel pellets,comprising the steps of: dosing and first blending (1) PuO2 with a first portion of UO2 powders and/or fuel manufacturing scrap, to form a first blend; micronizing (2) and forced sieving (3) the first blend, to form a conditioned first blend; selecting non-free-flowing UO2 as a second portion of UO2; mechanically granulating (29) the second portion of UO2 so as to form granulated free-flowing UO2, additionally dosing and second blending (4) the conditioned first blend, the granulated free-flowing UO2 and possibly scrap; adding and blending lubricants and/or poreformers (5), separately or in combination with the second blending step (4); pelletizing (6) the second blend; and sintering (7) the pellets thus formed, wherein said granulating step further comprises the steps of: compressing (30) non free-flowing UO2 to form tablets; crushing (31) the tablets, until a free-flowing crushed material has been formed; and using at least one portion of this free-flowing crushed material for said second blending operation (4).