Actinide reCycling by
SEParation and Transmutation

Overview > Objectives

INTRODUCTION

Presently, the European nuclear fleet leads to the annual production of approximately 2500 t/y of used fuel, containing 25 t of Plutonium, 3,5 t of minor actinides (MA, namely Np, Am, Cm) and 3 t of long-lived fission products (LLFPs). These MA and LLFPs stocks need to be managed in an appropriate way. Some European countries have chosen the strategy of closed fuel cycle, currently involving (i) the reprocessing of used nuclear fuels to recover uranium and plutonium and the recycling of plutonium in Light Water Reactors (ii) the vitrification of long lived radionuclides (the final waste being expected to be disposed of in deep geological repositories). Some others have chosen the direct geological disposal of nuclear used fuel. Both strategies are today the envisaged solutions depending on national fuel cycle options and waste management policies. Required time scale for the geological disposal exceeds our accumulated technological knowledge and this raises problems of public acceptance.

P&T has been initially pointed out in numerous studies as the strategy that can relax the constraints on the geological disposal, and reduce the monitoring period to technological and manageable time scales.

Despite the diversity between European Member States concerning nuclear power and envisaged fuel cycle policy ranging from the once through without reprocessing to the double strata fuel cycle ending with the ADS as the ultimate burner or Gen IV fast critical reactors multi-recycling all transuranic (TRUs), P&T requires an integrated effort at the European level and even worldwide.

When considering sustainable energy development worldwide, P&T should now be seen as fully integrated in a more global approach based on advanced fuel cycles associated to fast neutron reactors. These advanced nuclear systems should play a key role for not only minimising the production of long lived radioactive waste but also for optimising the use of natural resources and for increasing resistance to proliferation.

In parallel with the development of fast neutron reactors, a separation and treatment strategy needs to be implemented, aiming at a closed fuel cycle that includes the recycling of actinides. This strategy will in particular have to comply with the worldwide policy of safeguarding and proliferation resistance that favours recycling modes with a co-management of actinides. It would also permit the transition from the currently practiced mono-recycling of Plutonium in Light Water Reactors (LWR) to actinides (U, Pu, MA) recycling in Gen IV reactors, thereby allowing minimization of radiotoxicity in the ultimate waste. Even when considering the phase out of nuclear energy, the combination of P&T and dedicated burner such as ADS technologies, but this time at regional scale, would allow meeting the objectives of minimising the long lived waste to be ultimately disposed of.

Considering this evolution towards closed fuel cycles, it has been considered as a priority to strengthen the links and synergies with Transmutation as well as with geological disposal or interim storage activities. This evolution towards more integration should thus materialize and be consistent with the building of a European vision on P&T and more globally on future sustainable nuclear systems, such as those considered within the European Sustainable Nuclear Energy Technology Platform (SNE-TP).

Despite the different national strategies envisaged for managing nuclear wastes, the options for actinide recycling implementation show a significant common trunk which allows to draw a consensual European roadmap for research and development activities as well as for future pilot-scale fuel cycle facilities.

To implement this strategy at the horizon 2040-2050, it is expected around 2012 to review national positions, as well as the impact of the recycling of actinides on geological repository in terms of requirements and capacity. Scenarios for the recycling of actinides implementation and the evaluation of options such as homogeneous / heterogeneous recycling should also take into account the national capacities in fuel reprocessing and fuel fabrication, notably during the transient period. A review of group recovery of trans-uranium elements (TRUs) vs. minor actinides (MA) selective separation should also be undertaken by 2012. Priorities should also be given following the review of ADS vs. critical fast systems potentialities and their different coolants. All these reviews should lead to take decisions on demonstration facilities to be built at a time horizon 2015-2020.

OBJECTIVES of ACSEPT

In line with these timescales, the ACSEPT collaborative project (2008-2012) will provide a structured R&D framework with the ambitious objective to develop chemical separation processes compatible with fuel fabrication techniques, in view of their future demonstration at the pilot level. ACSEPT will develop elementary building blocks in terms of separation processes so as to offer technical solutions to the various fuel cycle options envisaged today. Flexibility will thus be kept as a main driving force while waiting for the consolidation of these options.

CONCLUSIONS

ACSEPT will provide the sound basis and fundamental improvements for future demonstrations of fuel treatment in strong connection with fuel fabrication techniques. The timelines of this four-year R&D project (2008-2012) should allow to offer technical solutions in terms of process separation that may be reviewed by Governments, European utilities as well as Technology Providers at that time horizon. By showing a technically feasible recycling of actinides strategy, ACSEPT will certainly produce positive arguments in the sense that :

- European decision makers and more globally public opinion could be convinced that some sound technical solutions for a better management of the nuclear wastes are now technologically feasible,

- One of the identified major difficulties for nuclear energy production, i.e. to guarantee the non-dissemination of hazardous radionuclides within the bio-sphere in the far future, is on the way to be solved, thus paving the way towards sustainability.

ACSEPT is a Collaborative Project of the EC FP7-Euratom, n 2007-211267

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