METHOD FOR PRODUCING PELLETIZED FUEL FOR FUEL ELEMENTS Russian patent published in 2007 - IPC G21C3/62 

FIELD: nuclear fuel production.

SUBSTANCE: proposed method for producing pelletized fuel for fuel elements includes estimation of powder engineering properties, preparation of powdered uranium UO₂ enriched by uranium 235 to 5% for compression, and its mixing with binder and with porophore. This is followed by mixture compression, binder thermal extraction, pellet sintering in gaseous reducing medium, drying, and rejection of faulty pellets. Estimation of powder engineering properties includes its test for spontaneous oxidation in the open by evaluating increase in weighted mass during its isothermal exposure to temperature of up to 80 °C for 1 h, evaluation of enhanced-particle-strength powder fraction by amount of remainder of non-disrupted agglomerates remained on sieve with grit of maximum 100 microns mesh in ultrasonic bath upon ultrasonic treatment. It also includes evaluation of less than 100 micron fraction content using sieve analysis, trial compression of pellets, evaluation of pellet strength, and pellet trial sintering and grinding, inspection for sintering shrinkage, density, open porosity, and exposed defects.

EFFECT: reduced manufacturing cost, enhanced yield.

8 cl, 1 dwg