HIGH BURNUP NUCLEAR URANIUM-GADOLINIUM FUEL ON BASIS FOR URANIUM DIOXIDE AND METHOD FOR ITS ACQUISITION (VERSIONS) Russian patent published in 2009 - IPC G21C21/02 

FIELD: energy technology.

SUBSTANCE: invention relates to the field of nuclear energy technology and can be used for the acquiring high burnup nuclear fuel on the basis of uranium dioxide. The technical task is resolved taking into account that high burnup uranium-gadolinium fuel contains aluminium of 0.005 to 0.03% and chrome from 0.005 to 0.015% in relation to the total mass of the uranium isotope, and also gadolimium oxide from 0.3 to10% in relation to the total mass of the mix of uranium dioxide, gadolinium oxide, and aluminium and chrome oxides prepared. Furthermore, the oxides are equally divided among the entire volume of the fuel, and the quantity of seed for uranium dioxide comprises 20 to 45 micrometres. In accordance to the first method for acquiring high burnup uranium gadolinium fuel on the basis of uranium dioxide, powder of uranium dioxide, gadolinium dioxide, chrome oxide and aluminium oxide and a plasticiser are prepared. The powder of chrome oxide and aluminium oxide are burnt in advance at a temperature of 700 to 800°C and are reduced to a size of less than 40 micrometres; a homogenous mix of uranium dioxide, gadolinium oxide, aluminium and chrome oxides with the plasticiser are prepared. Preparation with a powder press is performed, pressing tablets from the powder, their high temperature caking and polishing takes place. In accordance with the second technique uranium dioxide, uranium proto-oxide and oxide, gadolinium oxide, chrome oxide and aluminium oxide powders and a plasticiser are prepared. Chrome oxide and aluminium oxide are burnt in advance at a temperature of 700 to 800°C and is reduced to a size of less than 40 micrometres. A homogenous mix of powders is made from uranium dioxide, gadolinium oxide, uranium proto-oxide and oxide, aluminium and chrome oxides with the plasticiser. Furthermore, the uranium proto-oxide and oxide is to take up 15% of the total mass of uranium dioxide. Uranium proto-oxide and oxide, gadolinium oxide, aluminium and chrome oxides are then prepared using a powder press, pressing tablets with high temperature caking and polishing.

EFFECT: increased the level of burnup when used to 70-100 MW day/kg U.

10 cl, 2 dwg