Reduction and Resource Recycling of
High-level Radioactive Waste
through Nuclear Transmutation

Project 5
[Scenario and Process Concept]

Materialize a Scenario for LLFP Separation and Conversion and Study the Process Concept.

Project leader
Kazufumi Tsujimoto

Affiliation: Partitioning and Transmutation Technology Division
Nuclear Science and Engineering Center
Japan Atomic Energy Agency
Division Head
Research Field: Reactor physics, Transmutation system

Scenario and Process Concept

Purpose: To materialize a scenario for LLFP separation and conversion and to study the process concept.

  • Study on scenario of LLFP separation / conversion
Study simplification of disposal by separation / conversion (subsurface disposal of high-level radioactive waste by separating / converting MA, under separate development, in addition to LLFP) Study reusing rare metals by separation / conversion (quantitative evaluation of the possibility of reusing Pd and Zr which are elements containing LLFP)
  • Process concept study
Study of the separation and recovery process concept
Study of the transmutation process concept
Materialization of the separation / conversion system and evaluation of approximate cost

Current Results

Introduction of Research Results
High Level Waste (HLW)→TRU waste disposal Study of scenario (including marginal depth disposal)

Evaluation of radiation exposure dose accompanying reusing LLFP and study of clearance level

Current situation and environmental dynamics of industrial use of Zr and Pd

With the final goal of setting the clearance level for zirconium (Zr) and palladium (Pd) for which reuse is assumed from the viewpoint of evaluation of exposure dose accompanying the reuse of long-lived fission products. Study the production / usage situation of these elements and their behaviors in the environment with the aim of obtaining parameters necessary for setting clearance levels.

Results of investigation

Using palladium metal as a resource
Used for catalysts for purifying the exhaust gas of automobiles, dental materials, jewelry, etc.

Current status of recycling
Automobile exhaust gas catalysts - Approximately 60%
Petrochemical use catalysts - Nearly 100%
Electric and electronic industry parts - High purity scrap is recovered by precious metal dealers and low purity scrap is recovered together with other precious metals at copper and lead refining plants
Recycled dental materials - nearly all recycled