Fuel conversion projects help support international nuclear non-proliferation efforts by reducing the amount of highly enriched uranium in international commerce. IAEA involvement in this field stretches over 20 years, according to Pablo Adelfang, a senior official in the IAEA´s Division of Nuclear Fuel Cycle and Waste Technology.
At a briefing session held 20 September as part of the IAEA´s 51st General Conference, Mr. Adelfang, said that the Agency´s involvement includes addressing the diverse challenges that can be encountered during the conversion of research reactors from high enriched uranium (HEU) to low enriched uranium (LEU) fuel.
Mr. Adelfang explained that the Agency tailors its assistance to address the particular constraints of each project. "HEU to LEU fuel conversion projects differ significantly depending on several factors including the design of the reactor and fuel, the technical needs of the member state, the local nuclear infrastructure, and the available resources,"he said.
He presented a number of ´successful conversion stories´ that had been supported by the IAEA either through technical cooperation projects or through regularly funded activities. These include:
- The conversion of the RECH-1 reactor in Chile - fully converted in May 2006;
- Assistance in the conversion efforts of two cores in Tajoura, Libya;
- Support for the conversion of the Portuguese RPI research reactor and Poland's Maria reactor;
- Conversion of the 14MW TRIGA-reactor in Pitesti, Romania - completed in May 2006; and
- Supporting studies for the conversion of Chinese-designed Miniature Neutron Source Reactors (MNSR) through a coordinated research project.
The IAEA, Adelfang said, is also collaborating in a study exploring the feasibility of using LEU in Accelerator Driven Sub-Critical Systems, as well as supporting efforts towards the use of LEU in the production of molybdenum-99 – the most utilized radiopharmaceutical worlwide.
IAEA initiatives also include the development and maintenance of several databases with information related to research reactors spent fuel inventories, and the support of meetings and workshops held worldwide.
More than half of all the operational research reactors worldwide are still fuelled with HEU. This is considered undesirable due to the high-risk that the material can also be used to develop a nuclear explosive device. The IAEA works with its Member States both to return the fresh or spent highly enriched fuel - the so-called ´take back´ activities - and to convert their research reactors to LEU fuel. Projects and activities have directly supported an international programme initiated by the USA in 1978, called Reduced Enrichment for Research and Test Reactors (RERTR).