METHOD FOR PREPARATION OF URANIUM OXIDE POWDER FOR NUCLEAR FUEL PELLET FABRICATION FROM URANIUM OXIDE SCRAPS

摘要

A method for preparing uranium oxide powder for nuclear fuel pellet fabrication from uranium oxide scraps is provided, which includes dissolving uranium by adding carbonate solution with hydrogen peroxide into the uranium oxide scraps (step 1); adding acid to the solution in which uranium is dissolved at step 1, leaving uranium to precipitate, and absorbing carbon dioxide which is generated from solution during acidification of the uranium solution, with alkaline solution to recover carbonate solution (step 2); recovering the acid and the alkaline solutions used at step 2 (step 3); dehydrating agglomerated uranium oxide powder precipitated at step 2 under argon atmosphere, reductive heat treatment the agglomerated powder under hydrogen atmosphere, and passivation of forming a protective oxide film(step 4); milling the agglomerated uranium oxide powder prepared at step 4 (step 5); and mixing the uranium oxide power milled at step 5 and virgin uranium oxide powder (step 6).