[en] Incinerable wastes consist of the following standard composition corresponding to projected wastes from a future mixed oxide fuel fabrication plant with an annual throughput of 1700 kg (i.e. 5.7 m³) of ashes produced by the incineration facility: . 50% polyvinyl chloride (glove box sleeves), . 5% polyethylene (bags), . 35% rubber (equal amounts of latex and neoprene), . 10% cellulose (equal amounts of cotton and cleansing tissues). The work focused mainly on compaction by high-temperature isostatic pressing, is described in some detail with the results obtained. An engineering study was also carried out to compare this technology with two other ash containment processes: direct-induction (cold crucible) melting and cement-resin matrix embedding. Induction melting is considerably less costly than isostatic pressing; the operating costs are about 1.5 times higher than for cement-resin embedding, but the volume reduction is nearly 3 times greater

[en] Three conditioning processes for alpha-bearing solid waste incineration ashes were investigated and compared according to technical and economic criteria: isostatic pressing, cold-crucible direct-induction melting and cement-resin matrix embedding

[en] ACSEPT is an essential contribution to the demonstration, in the long term, of the potential benefits of actinide recycling to minimize the burden on the geological repositories. To succeed, ACSEPT is organized into three technical domains: (i) Considering technically mature aqueous separation processes, ACSEPT works to optimize and select the most promising ones dedicated either to actinide partitioning or to grouped actinide separation. A substantial review was undertaken either to be sure that the right molecule families are being studied, or, on the contrary, to identify new candidates. Results of the first hot tests allowed the validation of some process options. (ii) Concerning pyrochemical separation processes, ACSEPT is focused on the enhancement of the two reference cores of process selected within EUROPART with specific attention to the exhaustive electrolysis in molten chloride (quantitative recovery of the actinides with the lowest amount of fission products) and to actinide back-extraction from an An-Al alloy. R and D efforts are also brought to key scientific and technical issues compulsory for building a complete separation process (head-end steps, salt treatment for recycling and waste management). (iii) By integrating all the experimental results within engineering and systems studies, both in hydro and pyro domains, ACSEPT will deliver relevant flowsheets and recommendations to prepare for future demonstration at a pilot level, in relation with strategies developed through the SNE-TP. In addition, a training and education programme is implemented to share the knowledge among the partitioning community and the future generations of researchers

[en] Full text of publication follows: Nuclear energy is anticipated to be one of the possible energy sources which can allow the production of energy at high load with a high level of reliability without significant impact on the environment. Nowadays, most of the countries have chosen an open fuel cycle which basically considers spent nuclear fuel as a waste, whereas others like France, the United Kingdom, Japan and soon China reprocess their spent fuel to recover the plutonium (and partially U) to produce mixed oxide fuel to be irradiated in a second cycle. In a second step, considering the possibility of fertilising "2"3"8U to "2"3"9Pu in fast reactors, recycling major actinides is thought to be a major improvement towards the global sustainability of the nuclear energy: It will indeed allow the natural resource efficiency to be increased by orders of magnitude by consuming quantitatively the natural uranium resource involved. Driven by the Fukushima accident, nuclear energy is currently questioned about its overall environmental impact and footprint. However, very little information is available on the actual footprint of current and future nuclear systems. In order to bring insights on this issue, a life cycle assessment simulation tool NELCAS was developed based on the French nuclear closed fuel cycle. It allows the calculation of representative key environmental indicators and potential impact indicators for the whole nuclear systems. The very good consistency of the results with the literature data confirms the relevance and robustness of NELCAS. It was subsequently used to derive representative indicators for open and future potential fuel cycles, i.e. mixed GEN3 and GEN4 reactors fleet and full GEN4 reactors fleet. The results demonstrate the very significant improvement brought by the actinides recycling and the future fuel cycle. Most of the indicators are very significantly decreased with the implementation of long-term recycling strategies. This paper will present in the details the figures of merit of the different fuel cycles options and assess their respective sustainability. (authors)

[en] Alpha-bearing solid incineration wastes are conditioned for two principal reasons: to enhance the quality of the finished product for long-term storage, and to reduce the total waste volume. Isostatic pressing parameters were defined using containers 36 mm in diameter; the physicochemical properties of the compacted ashes were determined with 140 mm diameter containers and industrial feasibility was demonstrated with a large (300 mm diameter) container. Two types of ashes were used: ashes fabricated at Marcoule (either in devices developed by the CEA for the MELOX project with a standard MELOX composition, or by direct incineration at COGEMA's UP1 plant) and fly ash from a domestic waste incinerator. A major engineering study was also undertaken to compare the three known ash containment processes: isostatic pressing, melting, and cement-resin matrix embedding. The flowsheet, operational chronology and control principles were detailed for each process, and a typical plant layout was defined to allow comparisons of both investment and operating costs

[en] Among the targets proposed today for the transmutation of minor actinides (MA) in SFR and ADS, three U-free matrices (MgO, ZrO₂, and Mo metal) were selected and compared with the UO₂ matrix. The study was focused on the feasibility of reprocessing the selected targets by hydrometallurgy. It was shown that UO₂-MA targets could be reprocessed without major difficulty, whereas among the inert matrix targets, only MgO-MA targets could be industrially reprocessed today. There would, however, be a significant increase of the production of glass waste. (authors)

[en] Full text of publication follows. Nuclear energy is anticipated to be one of the possible energy sources which can allow the production of energy at high load with a high level of reliability without significant impact on the environment, specifically in terms of green-house gases. It could therefore promote the mitigation of the anticipated global climate change. However, nuclear energy is regularly questioned about its overall environmental impact and footprint, in particular after the Fukushima accident. However, very little information is available on the actual footprint of current and future nuclear systems. In order to bring insights on this issue, we developed a Life Cycle Assessment (LCA) simulation tool NELCAS based on the French nuclear system which allows the calculation of representative key environmental indicators and potential impact indicators for the whole nuclear systems. Indicators were chosen based on their occurrence in literature. Calculations were performed while considering the whole fuel cycle from ore-mining to geological repository and for each of the plant, the contribution from their construction, their operation and their future cleaning and dismantling. Transports were also considered all along the fuel cycle. All the matters and energy fluxes were considered and normalized versus the electric production. Whenever it is possible, actual and recent data were collected. In particular we widely used the Transparency and Safety Annual reports issued for each fuel cycle plant in France. Finally, statistical influence of the severe accidents was also considered based on the recent Fukushima accident. This presentation will detail the methodology and the overall results obtained for the different indicators. A specific emphasis will be given on the relative benefice of the nuclear energy by comparison to other energy sources. (authors)

[en] The preliminary assessment of an Enhancement Fuel and Target Reprocessing Plant (EFTRP) constitutes an integration study. The EFTRP is a reprocessing plant for fuel and targets implementing a future reprocessing process that should be available in the time frame between 2010 and 2020. The process will provide for improved liquid waste management, and will be capable of separating certain long-lived radionuclides: Np, Am, Cm, I and Tc. The plant will reprocess fuel and targets from a reactor population comprising pressurized water reactors using uranium oxide fuel (UOx PWRs) or mixed oxide fuel (MOx PWRs) and fast breeder reactors (FBRs) dedicated to incinerating the following radionuclides. Pu, Np, Am, Tc and I. (authors)

[en] An irradiated fuel reprocessing plant products purified plutonium and all sorts of wastes. PROBILUS program has been developed to calculate the transfer flux of materials. The data acquisition input being long, an expert system MARCMOD has been realized. PROBILUS was conceived like a standards collection. We wanted to automate the tedious tasks, to decrease the output result delays, and to improve the result quality. That is the reason why an expert system MARCMOD with a graphic interface has been carried out. With this tool the user may describe graphically his process, check the coherence of acquired informations, generate automatically the whole input data of PROBILUS, and change by interaction some predefined data

[en] This method was developed by the CEA to optimize the dimensions of a geological repository by taking account of technical and economic parameters. It involves optimizing radioactive waste storage conditions on the basis of economic criteria with allowance for specified thermal constraints. The results are intended to identify trends and guide the choice from among available options: simple and highly flexible models were therefore used in this study, and only nearfield thermal constraints were taken into consideration. Because of the present uncertainty on the physicochemical properties of the repository environment and on the unit cost figures, this study focused on developing a suitable method rather than on obtaining definitive results. The optimum values found for the two media investigated (granite and salt) show that it is advisable to minimize the interim storage time, implying the containers must be separated by buffer material, whereas vertical spacing may not be required after a 30-year interim storage period. Moreover, the boreholes should be as deep as possible, on a close pitch in widely spaced handling drifts. These results depend to a considerable extent on the assumption of high interim storage costs