Radiogenic lead from poly-metallic thorium ores as a valuable material for advanced nuclear facilities

摘要

Main purpose of the study is assessing reasonability for recovery, production and application of radiogenic lead as a coolant, neutron moderator and neutron reflector in advanced fast reactors and accelerator-driven systems (ADS). The following results were obtained: 1. Radiogenic lead with high content of isotope Pb-208 can be extracted from thorium or mixed thorium-uranium ores because Pb-208 is a final product of Th-232 natural decay chain. 2. The use of radiogenic lead with high Pb-208 content in advanced fast reactors and ADS makes it possible to improve significantly their neutron-physical and thermal-hydraulic parameters. 3. The use of radiogenic lead with high Pb-208 content in advanced fast reactors as a coolant opens the possibilities for more intense fuel breeding and for application of well-known oxide fuel instead of the promising but not tested enough nitride fuel under the same safety parameters. 4. The use of radiogenic lead with high Pb-208 content in advanced fast reactors as a neutron reflector opens a possibility for substantial elongation of prompt neutron lifetime. As a result, chain fission reaction in the reactor core could be slowed down, and the reactor operation could become safer. 5. The use of radiogenic lead with high Pb-208 content in ADS as a coolant can upgrade substantially the level of neutron flux in the ADS blanket. Thus, favorable conditions could be formed in the ADS blanket for effective transmutation of radioactive wastes with low cross-sections of radiative neutron capture.