Journal of Nuclear Fuel Cycle and Waste Technology

Vol-oxidizer is a device to convert UO2 pellets into U3O8 powder and to feed a homogeneous powder into a Metal Conversion Reactor in the ACP(Advanced Spent Fuel Conditioning Process). In this paper, we propose a design model of the vol-oxidizer, develop the new vol-oxidizer with a capacity of 20 kg HM/batch in UO2 pellets, and conduct a verification for the device. Design considerations include the internal structure, the capacity, the heating position of the device, and the size. The dimensions of the new vol-oxidizer are decided by the design model. We determine a permeability test of the U3O8 measuring the temperature distribution, and the volume of UO2 and U3O8. We manufactured the new vol-oxidizer for a 20 kg HM/batch in UO2 pellets, and then analyzed the characteristics of the U3O8 powder for the verification. The experimental results show that the permeability of the U3O8 throughout mesh enhance more than old vol-oxidizer, the oxidation time takes only 8 hours when compared with the 13 hours of the old device, and the average distribution of particle size is 40 . The capacities of new vol-oxidizer for a 20 kg HM/batch in UO2 pellets were agree well with the predictions of design model.

Keywords

UO2 pellet,Oxidation,U3O8,Design model,Demonstration,Vol-oxidizer,Mesh