Advances in treatment of wastes from reprocessing of spent fuel

Full text: Sustainable nuclear energy production relies on the optimisation of the fuel cycle by minimizing the long-term burden and the hazardousness of waste, and by making optimal use of energetic materials. The long-term management of high level long lived waste is a major issue, with significant public concern. In France, in December 1991, the Government prepared and the Parliament passed a law requesting in particular R and D of solutions and processes for: minimizing the quantity and the radiotoxicity of the HLLLW via partitioning and transmutation; waste conditioning and storage; deep geological disposal, with aiming at decision making process in 2006. Research has been conducted by CEA and ANDRA in a very sustained way and benefited from major cooperations in France (EDF, AREVA, CNRS, Universities), in Europe and internationally. Quite significant scientific and technical results have been produced and will contribute to making solutions available for coming national decisions. Among significant conclusions from the conduct of research, development and industrial experience: The reprocessing operations i) significantly reduce the HLLLW radiotoxicity and volume, ii) recover valuable materials, in particular resources from the waste, and recycle the plutonium, which is a highly energetic material and also the primary contributor to long-term radiotoxicity, iii) and condition the ultimate waste in a safe and durable manner, and in a very small volume; Recycling of plutonium in present LWRs is demonstrative at large scale, and 3rd generation reactors, such as EPR, can bring further possible improvements; For the future, advanced partitioning processes and transmutation in advanced reactors, could make it possible to recover and recycle all the actinides (uranium, plutonium, americium, curium, neptunium) and reduce the ultimate waste to the only fission products, the radiotoxicity of which drastically decreases in some hundred years; Geological disposal of ultimate waste is a safe long term burden free solution, taking benefit from the most important reduction of the quantity and toxicity of HLLLW brought by the closed fuel cycle; Flexibility in the back end of the fuel cycle operations is brought by the possibility of storing radioactive materials in a safe and robust manner. (author)