The IAEA is launching a new Coordinated Research Project (CRP) to address research and development (R&D) topics related to the decommissioning of sodium cooled fast reactors. The CRP, entitled “R&D to Advance Decommissioning of Sodium Cooled Fast Reactors”, will run for four years and take into account relevant experience and ongoing activities around the world.
Sodium cooled fast reactors (FRs) are designed to operate on neutrons with a fast energy spectrum. Such reactors do not need a moderator to slow down neutrons but require more highly enriched fuel than water cooled reactors. Fast reactors can be used to produce or ‘breed’ new fission isotopes, significantly enhancing fuel resources and enabling nuclear power to achieve long term sustainability.
Five sodium cooled FRs are in operation worldwide and others are approaching commissioning while older facilities, including experimental ones and prototypes, are in the process of being permanently shut down for decommissioning. Decommissioning approaches depend on national policy and strategy, the availability of storage capacities and final repositories as well as the ability to resolve specific technical issues.
A common challenge in decommissioning sodium cooled FRs is treatment of the coolant. Unlike in most other reactors, where the coolant is water, in these reactors the coolant is sodium based, which has challenging chemical features. Other challenges include activated corrosion products in the sodium due to its chemical reactivity and the consequences of leakage during the operation of some reactors.
CRP Overall Objective
The objective of the CRP is to enhance practical knowledge in the decommissioning of sodium cooled FRs, considering their specific design and make-up. It focuses on R&D and other technical needs to fully complete dismantling operations or to prepare for the safe enclosure of the facility in case dismantling is deferred until a later date.
Specific Research Objectives:
1. Consider specific technical activities in decommissioning sodium cooled FRs;
2. Evaluate a large scope of technical aspects such as best practices, R&D to support decommissioning including decontamination and dismantling, 3D modelling, digital simulations, primary and secondary waste management etc., in order to support implementation of the optimal approaches to safe decommissioning;
3. Provide benchmarking of decommissioning features for different types of sodium cooled FRs;
4. Develop an algorithm to optimize the decommissioning waste packaging considering radiological criteria and minimization of packages, whose tool should reflect dose rate measurements and 3D modelling of packaging;
5. Minimize secondary waste produced by the coolant decontamination, including waste contained and to be extracted from the cold traps and placed in specific package(s) for long-term storage;
6. Prepare and publish an IAEA report on the CRP topic summarizing achieved results.
How to join this CRP:
Proposals for Research Contract or Agreement should be submitted by email no later than 4 March 2022 to the IAEA’s Research Contracts Administration Section, using CRP ID ‘T24009’and the appropriate template on the CRA web portal. A kick-off meeting for the project is tentatively scheduled for 2022 in Vienna.
For further information, potential applicants can contact the Project Officers at the Decommissioning and Environmental Remediation Section, Division of Nuclear Fuel Cycle and Waste Technology, Department of Nuclear Energy, IAEA.