METHOD OF FUEL PELLET PRODUCTION FOR NUCLEAR FUEL ELEMENTS Russian patent published in 2009 - IPC G21C3/62 

FIELD: chemistry; power engineering.

SUBSTANCE: invention relates to nuclear industry, particularly to production of fuel pellets from uranium dioxide (VO₂), produced by ADU method for nuclear fuel elements. Essence of the invention in the following: ammonium polyuranate (ADU-process) is precipitated in a stage, before mixing powder of uranium dioxide is put through screen, mesh of which is not more than 630 micron with simultaneous reducing and sifting through the same oversize screen, mixing is carried out together with dry organic binding agent 1,2-distearylethylenediamine - DISED of formula C₃₈H₇₆O₂N₂ and powder of uranium oxide concentrate having total specific surface area not more than 1.2 m²/g and particle size 40 micron, pressing is carried out in compact density equalled 5.4-5.6 g/cm³. Ammonium polyuranate is precipitated with ammonium diuranate solution, the concentration of which is 50-80 g/l, pH=6.4-7.0, feed speed - 200-400 l/h, powder of uranium oxide concentrate is derived by oxidising sintered pellets preliminary reduced so that the particle size is not more than 5 mm in furnace during 3-4 hours at 360-380°C and air consumption equalled 100 l/h per 1 kg of uranium dioxide.

EFFECT: precipitation of powder on the condition providing stable properties of powder, decrease of particle size, content increase of back uranium oxide concentrate admixture, increase of compacting pressure with reducing negative consequences for each applied procedure.

2 cl, 2 tbl, 2 ex