Demonstrated fuel cycle

Traditional demonstrated fuel cycle (DFC) view. For those already with access to or reserves of uranium, such as the United States, France, and Canada, the uranium fuel cycle is an already demonstrated fuel cycle (DFC) and is fine while uranium is cheap and assuredly available. 

This volume provides incentives for further development of sustainable fuel cycles through novel and interdisciplinary approaches to an Earth science-related topic. The issue of power generation and associated waste accumulation is of enormous political and social importance for people around the globe, and this book demonstrates that geological research is essential in providing solutions to some of the most pressing problems of today s society. 

Morita, Y., Yamaguchi, I., Fujiwara, T., Koizumi, H., Tachimori, S. 2000. A demonstration of the 4-group partitioning process with real high-level liquid waste. ATALANTE 2000 Scientific Research on the Back-end of the Fuel Cycle for the 21st Century, October, Avignon, France. 

Modolo, G., Asp, H., Vijgen, H., Malmbeck, R., Magnusson, D., Sorel, C. 2007. Demonstration of a TODGA/TBP process for the recovery of bivalent actinides and lanthanides from a PUREX raffinate. Global 2007 Advanced Nuclear Fuel Cycles and Systems, September, Boise, ID. 

Magnusson, D., Christiansen, B., Glatz, J.P., Malmbeck, R., Modolo, G., Serrano Purroy, D., Sorel, C. 2008. Demonstration of minor actinide separation from a genuine PUREX raffinate by TODGA/TBP and SANEX reprocessing. ATALANTE 2008 Nuclear Fuel Cycles for a Sustainable Future, May, Montpellier, France. 

C. 2008. Towards an optimized flow-sheet for a SANEX demonstration process using centrifugal contactors. ATALANTE 2008 Nuclear Fuel Cycles for a Sustainable Future, May, Montpellier, France. 

The CEA has sponsored the ATALANTE conferences to provide an international forum for presentation and discussion of the advances for future fuel cycles and waste management that are needed for sustainable development of nuclear energy. Abstracts of the papers from the Avignon (2000) and Nimes (2004) conferences are available on the web at www-atalante2004.cea.fr. They demonstrate that centrifugal contactors are being used for flowsheets covering various nuclear processes. 

The situation has changed dramatically during the last 20 years. No closed fuel cycle of the type originally envisaged to be operational in the 1980s exists today. Although the closure of the nuclear fuel cycle has been experimentally demonstrated in France, Japan, Russia and the United Kingdom, it has not been demonstrated yet on a commercial scale. 

The fuel cycle concept is much more influenced hy the chemical behaviour of the actinides during the reprocessing of the Th-containing fuel. It could he demonstrated during the first hot operations (3.), that Np ends up quantitatively in the waste stream, hut Pu is distributed in the product streams (90 % in the Th-, 10 % in the U-stream). These facts contradict strongly the above mentioned fuel cycle strategy, since Pu is no waste component and the Pu-contaminated Th cannot he used for the fresh fuel fabrication with respect to its high specific a-activity. 

We discussed the sources of artificial occurrence of " Tc at the beginning of this chapter and demonstrated that the nuclear fuel cycle is the predominant source of Tc in the environment. Other, much less important, sources are the fallout from nuclear weapons testing, the Chernobyl accident, nuclear power production and the radiopharmaceutical use of the metastablc "Tc decaying to ground state Tc. The natural occurrence of Tc formed in the earth s crust by spontaneous fission of and neutron-induced fission of in uranium ores are negligible. 

Interest now is centered on the thorium cycle (23) and laboratory studies have continued to investigate both an adaptation of the Thorex process to CANDU fuel and the application of the amine process to recovering uranium-233 from irradiated thorium. The program to develop and fully demonstrate the thorium fuel cycle has been outlined, and would require about 25 years to complete. However, the current research level will not be expanded until a decision can be taken by the Canadian Government when the information from the current International Nuclear Fuel Cycle Evaluation has been assessed. 

Demonstration of fuel cycle closure in some cases ... 

The Experimental Breeder Reactor-II (EBR-II) was designed as a 62.5 MWt, metal fueled, pool reactor with a conventional 19 MWe power plant. The productive life of the EBR-II began with first operations in 1964. Demonstration of the fast reactor fuel cycle, serving as an irradiation facility, demonstration of fast reactor passive safety and lastly, was well on its way to close the fast breeder fuel cycle for the second time when the Integral Fast Reactor program was prematurely ended in October 1994 with the shutdown of the EBR-II. 

The main applications are concerned with the production of ultra-pure hydrogen for laboratory and small scale electrolysers and the processing of tritiated water. Recent studies into alkahne electrolysis cells using thin-wall Pd-Ag tubes have demonstrated the applicabihty of these technologies for commercial hydrogen electrolysers. Other tests have verified the use of these hollow cathode cells for recovering tritium from tritiated water in the fuel cycle of the next fusion reactors. 

Verification of high availability and economical prospects of FBR fuel reprocessing are essential for deployment of FBR and its fuel cycle. In order to accomplish them at future pilot plant, hot engineering demonstrations of important process and equipment are necessary in advance. From this viewpoint, PNC has... 

In all cases the core performance was determined in terms of safety parameters such as the Doppler coefficient and the sodium void reactivity, the fuel cycle length (taking account of the rapid loss of reactivity with bumup), the absorber worth requirement, the fuel residence time, etc. It was possible to demonstrate the feasibility of the core, including the variants mentioned above, in terms of overall safety and economic performance. 

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