Analysis of Spent Fuel Characteristics in Different Scenarios of Closing the Nuclear Fuel Cycle

Calculation analysis of the isotope and radiation-migration characteristics of spent nuclear fuel (SNF) in the open fuel cycle of thermal reactor VVER-1000 and in closed cycle of fast reactor with lead-bismuth coolant has been fulfilled. Effects of including an accelerator-driven system (ADS) into the system for transmutation of minor actinides (MA) into the cycles studied on the SNF characteristics has been reviewed. The application of ADS-burner of MA symbiotically with operating VVER-1000 reactors has been shown to decrease the high-level wastes' activity approximately 20 times within the interval from the end of cooling in reactor to 105 years; in this case the principle of radiation-migration balance of activity in the underground burial for ~500 years is met as well. The calculation analysis gives grounds to conclude that the use of ADS for burning minor actinides in closed fuel cycle of fast reactors with lead-bismuth coolant, where U, Pu, and MA are recycled, with natural uranium as a makeup fuel, does not provide any special advantages in terms of radiation and migration characteristics of spent fuel and its wastes. (author)