Transmutation of MAs and LLFPs with a lead-cooled fast reactor

Area of Science:

• Nuclear Engineering
• Radiochemistry
• Materials Science

Background:

• Nuclear waste management is a critical challenge for sustainable nuclear energy.
• Minor actinides (MAs) and long-lived fission products (LLFPs) pose significant disposal difficulties.
• Existing methods for handling these radioactive materials are often insufficient.

Purpose of the Study:

• To propose and evaluate a novel scheme for transmuting MAs and LLFPs.
• To assess the feasibility of using a lead-cooled fast reactor (LFR) for nuclear waste management.
• To optimize LLFP composition for efficient transmutation.

Main Methods:

• Simulation of a lead-cooled fast reactor (LFR) core.
• Loading MAs into fuel assemblies and LLFPs into blanket assemblies for transmutation.
• Comparative analysis of neutron flux distribution, spectra, and k-effective with and without MAs.
• Optimization of LLFP composition to achieve self-sustained transmutation.

Main Results:

• The LFR scheme enables transmutation of most MAs and LLFPs.
• Support ratios indicate self-sustained transmutation is achievable for key nuclides.
• High transmutation rates were calculated for MAs (e.g., 15.18%/y for 241Am) and LLFPs (e.g., 1.17%/y for 107Pd).
• Neutronic parameters were analyzed to understand MA loading effects.

Conclusions:

• A lead-cooled fast reactor (LFR) is a viable technology for managing nuclear wastes with high long-lived radioactivity.
• The proposed scheme offers a promising solution for reducing the burden of nuclear waste.
• Further research can optimize LFR designs for enhanced waste transmutation efficiency.