Immobilization of Irradiated Fuel
Development of Technology for Immobilization of Irradiated Fuel not Subject to Reprocessing.
Tech Area / Field
- FIR-FUE/Reactor Fuels and Fuel Engineering/Fission Reactors
3 Approved without Funding
Khlopin Radium Institute, Russia, St Petersburg
- TsNIIKM PROMETEY (Construction Materials), Russia, St Petersburg
- Lawrence Livermore National Laboratory, USA, CA, Livermore
Project summaryThe most safe means for the management of irradiated fuel from power reactor facilities is the reprocessing at radiochemical plants. The realization of a closed fuel cycle conception pursues two main goals:
- Recovery and recycle of uranium and plutonium in reactors of nuclear power plants;
- Processing of waste containing long-lived radionuclides, their conditioning with subsequent isolation in geological formations.
However, at present great amounts of irradiated and nonirradiated nuclear materials are accumulated which for some reasons cannot bereprocessed at operating radio-chemical plants or their reprocessing is not economically attractive.
Steady accumulation of radioactive and nuclear-dangerous materials, for example fuel of research reactors, propulsion reactors (nuclear submarines, ice-breakers), RBMK reactor fuel, damaged fuel elements and assemblies requires large capital costs for building and operation of special storage facilities. At the same time constant growth of amounts of nonreprocessed fuel materials increases the risk of emergency situations and environmental contamination.
The isolation of irradiated fuel in concrete or metallic containers does not ensure safe conditions for hundreds and thousands of years.
An alternative means for safe isolation of high-level and nuclear-dangerous materials is the incorporation of wastes into crystalline mineral-like matrices, which have no drawbacks of concrete and metallic materials.
Investigations carried out at the RPA "V.G. Khlopin Radium Institute" have shown the feasibility for synthesis of artificial mineral-like materials suitable for high-level waste immobilization.
Natural analogs of obtained materials exist in nature for millions of years without changing their characteristics.
The purpose of the Project proposed is the development of a technology for immobilization of any type of irradiated fuel without reprocessing using extraction technologies.
The goal pursued may be achieved by incorporating the fuel assemblies or single fuel elements into highly stable mineral-like matrices ensuring a reliable isolation of radionuclides from the environment. The synthesis of mineral-like matrices is a solid phase reaction without forming any liquid or gaseous wastes.
The present Project includes the following experimental studies:
- Study of processes for plasma-chemical synthesis of press powders of matrix materials:
- Synthesis of mineral-like matrices by hot isostatic pressing;
- Study of the composition and physico-chemical properties of press powders and model matrices;
- Conducting the experiments on immobilization of samples simulating fuel elements and studying the properties of products obtained.
At the final stage of the work an experiments will be carried out with irradiated fuel samples using the remotely operated equipment installed in hot cells.
To perform the proposed complex investigation, the existing equipment will be modernized, and additional units for the operation with irradiated materials of high activity will be created. Irradiated fuel samples incorporated into a crystalline matrix will be subject to a comprehensive analysis including the determination of chemical stability of synthesized shells.
The result of proposed works will be the development for the first time technology of preparing the irradiated fuel not suitable to reprocessing for the disposal into geological formations.
The data obtained will make it possible to prepare initial data for designing the commercial equipment and to give recommendations on parameters of irradiated fuel immobilization process.
The realization of the proposed technology on industrial scale will allow us to isolate great amounts of radioactive and nuclear dangerous materials and to decrease the risk of ecological disaster.
The results of the proposed Project are obviously important for countries with developed atomic power engineering (Russia, USA, Great Britain, Japan etc.) which are interested in safe isolation of radioactive waste and the decrease of risk of ecological catastrophe.
The authors of Project are interested in any type of collaboration with international and national organizations, research institutions, private companies and experts from the Parties to the ISTC Agreement.
The International Science and Technology Center (ISTC) is an intergovernmental organization connecting scientists from Kazakhstan, Armenia, Tajikistan, Kyrgyzstan, and Georgia with their peers and research organizations in the EU, Japan, Republic of Korea, Norway and the United States.
ISTC facilitates international science projects and assists the global scientific and business community to source and engage with CIS and Georgian institutes that develop or possess an excellence of scientific know-how.