METHOD FOR RECOVERING IRRADIATED NUCLEAR FUEL (ALTERNATIVES) Russian patent published in 2005 - IPC

FIELD: handling spent nuclear fuel.

SUBSTANCE: proposed method meant for recovering irradiated nuclear fuel to obtain joint solution of U and Pu includes extraction of U, Pu, Np, and Te from nitric acid solution by means of 30% solution of tributyl phosphate and separation of Np and Te. Next re-extraction of Pu is effected by means of depleted or regenerated four-valence uranium solution. The latter is supplied to central part of Pu re-extraction unit at flowrate ensuring weight proportion of Pu : U = 1 : 4 in re-extract. At the same time solution of 0.1 - 0.7 mole/l of nitric acid is fed to end of unit at flowrate excluding breakthrough of U(IV) with extract of U(VI). Joint re-extraction of plutonium and part of uranium is also conducted by completing agent solution supplied in constant composition and at flowrate affording complete re-extraction of plutonium. At the same time solution of 0.1 - 0.7 mole/l of nitric acid is fed to end of unit at flowrate ensuring desired amount of uranium supply to mixed re-extract.

EFFECT: provision for preventing spread of fissionable materials.

2 cl, 1 dwg, 2 tbl, 2 ex