METHOD OF FUEL PELLETS PRODUCTION FOR NUCLEAR FUEL ELEMENTS Russian patent published in 2009 - IPC G21C21/02 G21C3/62 

FIELD: chemistry; power engineering.

SUBSTANCE: invention relates to nuclear industry and can be applied during production of uranium dioxide UO₂ fuel pellets applied for nuclear fuel elements (FE). Method of fuel pellets production for nuclear fuel elements comprises using plasticiser "DISED" as a dry binding agent containing N,N-bisstearylal ethylene -diamine C₃₈H₇₆N₂O₂ with particle size ranging from 0.4 to 1.0 mm. Plasticiser "DISED" is mixed with powder of dioxide and uranium oxide concentrate stepwise by adding pore agent "POROFOR" mixed with plasticiser "DISED" consisting of azidocarbonamide C₂H₄N₄O₂ with particle size not more than 20 micron. The content of plasticiser "DISED" is 0.2-0.6 wt %, and pore agent "POROFOR" - 1 wt %, from the weight of moulding powder. Plasticiser "DISED" added in advance is used as a lubricant within pressing pellets, thermal extraction of plasticiser "DISED" and pore agent "POROFOR" is carried out in hydrogen media in tunnel type furnace by aging pellets during 5.5 hours with increasing temperature from 20°C to 600°C, followed with further aging within 1 hour and increasing temperature from 600°C to 1200°C and final dissolution of the plasticiser within 3 hours with increasing temperature from 1200°C to 1750°C.

EFFECT: increased yield of usable uranium dioxide pellets, extension of operational life of furnace, heaters, molybdenic boats and improvement of working conditions.

1 cl