Method for preparing UO2 mixture powder for nuclear fuel manufacturing by means of IBC blender, and UO2 mixture powder for nuclear fuel manufacturing, prepared thereby
AssigneeKepco Nuclear Fuel Co., Ltd.
InventorsBohyun Jo, Hui Sung Choi, Dong Hyun Cho, Ji Hwan Son, Junseok Park
Life of this patent
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Abstract
A method for preparing a UO2 mixture powder for nuclear fuel manufacturing, comprises the steps of: (a) weighing and sieving, by means of an automatic injection device, a UO2 powder, a porogen and a lubricant, and injecting same into a UC container; and (b) mixing the UO2 powder, the porogen and the lubricant by means of an IBC blender. According to a method for preparing a UO2 mixture powder for nuclear fuel manufacturing, mixing time is short, and degrees of mixing and homogeneity of a prepared UO2 mixture powder are excellent.
Claims5
A method of preparing a UO2 powder mixture for nuclear fuel manufacturing, the method comprising:
- (a) weighing and sieving a porogen and a lubricant using an automatic injection device;
- and injecting the porogen and lubricant together at an initial stage into a container containing UO2 powder;
- and
- (b) mixing the UO2 powder, the porogen, and the lubricant using a blender,
- wherein the mixing in the (b) comprises:
- forward mixing performed under conditions in which:
- a rotation speed of the blender is in a range of 10 to 14 rpm,
- a container filling rate of the powder is in a range of 50 to 70 vol %, and
- a mixing time is in a range of 20 to 30 minutes, and
- backward mixing performed under conditions in which:
- a rotation speed of the blender is in a range of 10 to 14 rpm, and
- a mixing time is about 10 minutes, and
- wherein the UO2 powder is contained in an amount of 10 to 500 kg, and 0.08 to 10 parts by weight of the porogen and 0.05 to 1 part by weight of the lubricant are contained with respect to 100 parts by weight of the UO2 powder.
A method of manufacturing a UO2 nuclear fuel, the method comprising:
- preparing a UO2 powder mixture by:
- (a) weighing and sieving a porogen and a lubricant using an automatic injection device;
- and injecting the porogen and lubricant together at an initial stage into a container containing UO2 powder;
- and
- (b) mixing the UO2 powder, the porogen, and the lubricant using a blender,
- wherein the mixing in the (b) comprises:
- forward mixing performed under conditions in which:
- a rotation speed of the blender is in a range of 10 to 14 rpm,
- a container filling rate of the powder is in a range of 50 to 70 vol %, and
- a mixing time is in a range of 20 to 30 minutes, and
- backward mixing performed under conditions in which:
- a rotation speed of the blender is in a range of 10 to 14 rpm, and
- a mixing time is about 10 minutes, and
- wherein the UO2 powder is contained in an amount of 10 to 500 kg, and 0.08 to 10 parts by weight of the porogen and 0.05 to 1 part by weight of the lubricant are contained with respect to 100 parts by weight of the UO2 powder;
- manufacturing a UO2 molded pellet by pressing the UO2 powder mixture;
- manufacturing a UO2 sintered pellet by sintering the UO2 molded pellet;
- and
- manufacturing a UO2 ground pellet by grinding the sintered pellet so that the sintered pellet maintains a uniform diameter,
- wherein a defect rate is 5% or less, and the sintered pellet has a density of 10.30 to 10.58 g/cm3.
Dependencies are inferred from the claim text.