Method of regenerating nuclear fuels

The present invention relates to a novel method of regenerating nuclear fuels in which the depleted uranium fuels (with a concentration of, for example, 2%) are mixed with highly concentrated uranium (for example 4%) to produce nuclear fuels of desired concentration (for example 3%). In conventional systems, low-concentration fuel is mixed with high-concentration uranium in the same phase. For example, used uranium is usually obtained in the form of uranyl nitrate or uranium oxide, while the high concentration uranium is provided as uranium hexafluoride. In this case, the uranile nitrate is converted to uranium hexafluoride prior to mixing by means of a pre-treatment plant. In the present invention, highly concentrated uranium hexafluoride gas and ammonia are introduced into an aqueous solution of low concentration uranyl ion to produce the sedimentation of ammonium diuranate. A carrier gas may be introduced into the solution together with the uranium hexafluoride or ammonia gas to effect a high degree churning. (R. Masui)