TRU Recycling Options for Environmentally Friendly and Proliferation-Resistant Nuclear Fuel Cycle of FBR

Author(s):  
Sidik Permana ◽  
Mitsutoshi Suzuki

The embodied challenges for introducing closed fuel cycle are utilizing advanced fuel reprocessing and fabrication facilities as well as nuclear nonproliferation aspect. Optimization target of advanced reactor design should be maintained properly to obtain high performance of safety, fuel breeding and reducing some long-lived and high level radioactivity of spent fuel by closed fuel cycle options. In this paper, the contribution of loading trans-uranium to the core performance, fuel production, and reduction of minor actinide in high level waste (HLW) have been investigated during reactor operation of large fast breeder reactor (FBR). Excess reactivity can be reduced by loading some minor actinide in the core which affect to the increase of fuel breeding capability, however, some small reduction values of breeding capability are obtained when minor actinides are loaded in the blanket regions. As a total composition, MA compositions are reduced by increasing operation time. Relatively smaller reduction value was obtained at end of operation by blanket regions (9%) than core regions (15%). In addition, adopting closed cycle of MA obtains better intrinsic aspect of nuclear nonproliferation based on the increase of even mass plutonium in the isotopic plutonium composition.

Author(s):  
Andre´ Voßnacke ◽  
Wilhelm Graf ◽  
Roland Hu¨ggenberg ◽  
Astrid Gisbertz

The revised German Atomic Act together with the Agreement between the German Government and the German Utilities of June 11, 2001 form new boundary conditions that considerably influence spent fuel strategies by stipulation of lifetime limitations to nuclear power plants and termination of reprocessing. The contractually agreed return of reprocessing residues comprises some 156 casks containing vitrified highly active waste, the so-called HAW or glass canisters, coming form irradiated nuclear fuel assemblies to be shipped from COGEMA, France and BNFL, UK to Germany presumably until 2011. Several hundred casks with compacted residues and other waste will follow. The transports are scheduled presumably beyond 2020. The central interim storage facilities in Ahaus and Gorleben, formerly intended to accumulate up to 8,000 t of heavy metal (HM) of spent fuel from German nuclear power plants, offer sufficient capacity to receive the totality of residues to be returned from reprocessing abroad. GNB has developed, tested, licensed, fabricated, loaded, transported and stored a large number of casks for spent fuel and is one of the world leaders for delivering spent fuel and high level waste casks. Long-term intermediate storage of spent fuel is carried out under dry conditions using these casks that are licensed for transport as well as for storage. Standardized high performance casks such as the types CASTOR® HAW 20/28 CG, CASTOR® V/19 and CASTOR® V/52 meet the needs of most nuclear power plants in Germany. Up to now GNS has co-ordinated the loading and transport of 27 casks loaded with 28 canisters each from COGEMA back to Germany for storage in Gorleben for up to 40 years. In all but one case the cask type CASTOR® HAW 20/28 CG has been used.


Estimates are given of the total quantities of radioactivity, and of the contribution from different isotopes to this total, arising in the wastes from civil nuclear power generation; the figures are normalized to 1 GW (e) y of power production. The intensity of the heat and y-radiation emitted by the spent fuel has been calculated, and their decrease as the radioactivity decays. Reprocessing the spent fuel results in 95% or more of the fission products and higher actinides being concentrated in a small volume of high-level, heat-emitting waste. The total decay curve of unreprocessed spent fuel or of the separated high-level waste is dominated by the decay of some fission products for a few hundred years and then by the decay of some actinide isotopes for some tens of thousands of years. The residual activity is compared with that of the original uranium ore. Some of the long-lived activity will appear in other waste streams, particularly on the fuel cladding, and the volumes and activities of these wastes arising in this country are recorded. The long-lived activity arising from reactor decommissioning will be small compared with the annual arisings from the fuel cycle.


2018 ◽  
Vol 4 ◽  
pp. 4
Author(s):  
Timothée Kooyman ◽  
Laurent Buiron ◽  
Gérald Rimpault

In the case of a closed fuel cycle, minor actinides transmutation can lead to a strong reduction in spent fuel radiotoxicity and decay heat. In the heterogeneous approach, minor actinides are loaded in dedicated targets located at the core periphery so that long-lived minor actinides undergo fission and are turned in shorter-lived fission products. However, such targets require a specific design process due to high helium production in the fuel, high flux gradient at the core periphery and low power production. Additionally, the targets are generally manufactured with a high content in minor actinides in order to compensate for the low flux level at the core periphery. This leads to negative impacts on the fuel cycle in terms of neutron source and decay heat of the irradiated targets, which penalize their handling and reprocessing. In this paper, a simplified methodology for the design of targets is coupled with a method for the optimization of transmutation which takes into account both transmutation performances and fuel cycle impacts. The uncertainties and performances of this methodology are evaluated and shown to be sufficient to carry out scoping studies. An illustration is then made by considering the use of moderating material in the targets, which has a positive impact on the minor actinides consumption but a negative impact both on fuel cycle constraints (higher decay heat and neutron) and on assembly design (higher helium production and lower fuel volume fraction). It is shown that the use of moderating material is an optimal solution of the transmutation problem with regards to consumption and fuel cycle impacts, even when taking geometrical design considerations into account.


Author(s):  
Yongsoo Hwang ◽  
Ian Miller

This paper describes an integrated model developed by the Korean Atomic Energy Research Institute (KAERI) to simulate options for disposal of spent nuclear fuel (SNF) and reprocessing products in South Korea. A companion paper (Hwang and Miller, 2009) describes a systems-level model of Korean options for spent nuclear fuel (SNF) management in the 21’st century. The model addresses alternative design concepts for disposal of SNF of different types (CANDU, PWR), high level waste, and fission products arising from a variety of alternative fuel cycle back ends. It uses the GoldSim software to simulate the engineered system, near-field and far-field geosphere, and biosphere, resulting in long-term dose predictions for a variety of receptor groups. The model’s results allow direct comparison of alternative repository design concepts, and identification of key parameter uncertainties and contributors to receptor doses.


Author(s):  
Dennis L. Berry ◽  
Bart R. Callan

A global partnership between nuclear energy supplier nations and user nations could enable the safe and secure expansion of nuclear power throughout the world. Although it is likely that supplier nations and their industries would be anxious to sell reactors and fuel services as part of this partnership, their commitment to close the fuel cycle (i.e., permanently take back fuel and high-level waste) remains unclear. At the 2007 Waste Management Symposia in Tucson, Arizona, USA, a distinguished international panel explored fuel take back and waste disposal from the perspective of current and prospective user nations. This paper reports on the findings of that panel and presents a path for policy makers to move forward with the partnership vision.


2021 ◽  
Vol 7 ◽  
pp. 21
Author(s):  
Léa Tillard ◽  
Xavier Doligez ◽  
Gérald Senentz ◽  
Marc Ernoult ◽  
Jiali Liang ◽  
...  

This article presents an assessment of fuel cycle parameter impact on waste production through the prism of vitrified container and minor actinide masses, using a scenario simulated with the CLASS code. The number of canister introduces a new focus on waste production estimation for a nuclear fleet, as it helps to set the repository size for deep geological disposal of high level waste. To evaluate the number of canisters, dedicated developments to model a simplified waste vitrification unit in the CLASS package are presented. It relies on artificial neural network estimations of decay heat, α radiation and mass content, for different material flow coming from reprocessing and sent to vitrification. Then, the studied scenario considers a transition from a PWRs plutonium mono-recycling fleet to a plutonium multi-recycling fleet. Vitrified waste container production is calculated as a function of different material reprocessing options. Simulations shows that up to 19% variation may be observed (in 2060) in canisters’ total number depending on the different assumptions. Impact of vitrification parameters such as the size of buffer before vitrification is also analysed and the importance of mixing material coming from MOX and MIX spent fuels with material from UOX spent fuels is clearly established.


2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
A. Schwenk-Ferrero

Germany is phasing-out the utilization of nuclear energy until 2022. Currently, nine light water reactors of originally nineteen are still connected to the grid. All power plants generate high-level nuclear waste like spent uranium or mixed uranium-plutonium dioxide fuel which has to be properly managed. Moreover, vitrified high-level waste containing minor actinides, fission products, and traces of plutonium reprocessing loses produced by reprocessing facilities has to be disposed of. In the paper, the assessments of German spent fuel legacy (heavy metal content) and the nuclide composition of this inventory have been done. The methodology used applies advanced nuclear fuel cycle simulation techniques in order to reproduce the operation of the German nuclear power plants from 1969 till 2022. NFCSim code developed by LANL was adopted for this purpose. It was estimated that ~10,300 tonnes of unreprocessed nuclear spent fuel will be generated until the shut-down of the ultimate German reactor. This inventory will contain ~131 tonnes of plutonium, ~21 tonnes of minor actinides, and 440 tonnes of fission products. Apart from this, ca.215 tonnes of vitrified HLW will be present. As fission products and transuranium elements remain radioactive from 104to 106years, the characteristics of spent fuel legacy over this period are estimated, and their impacts on decay storage and final repository are discussed.


Author(s):  
Salomon Levy

The development of and support for small modular nuclear power plants (NPPs) is gaining strong momentum in USA. The reasons are that they could require reduced financing and shortened construction schedule. Also, they could address the reduced size need for electricity in some USA locations and, in particular, in developing foreign countries. However, the prevailing enthusiasm needs to be moderated until several potential obstacles are overcome. There are three principal USA obstacles: (1) the successful licensing and certification of the SMRs by the Nuclear Regulatory Commission (NRC) to confirm their safety; (2) SMRs ability to demonstrate that they can compete financially against less costly modular natural gas power plants or the limited purchase of electricity from new large light water reactors (LWRs); and (3) the need to work into the prevailing fuel cycle while not deteriorating spent fuel disposal or increasing proliferation. Clearly, Babcock & Wilcox’s and Nu Scale Power’s SMRs have the earliest chance for success because they would rely upon the present LWR regulatory and fuel cycle experience. Their main obstacle will be demonstrated costs from prototype plants and the willingness to accept fixed turnkey contracts for additional units. The more visionary SMRs such as GE-Hitachi PRISM or the Hyperion Power Generation smaller liquid metal closed fuel cycle reactors will have to overcome more difficult and lengthy regulatory assessments. Also, a complete fuel cycle infrastructure will need to be developed. Penetration of developing foreign countries will be the most difficult because it will demand the development and establishment of a nuclear safety infrastructure in those countries. The International Atomic Energy Agency (IAEA NG-G-31) has detailed the numerous actions and large time schedule and efforts to achieve an adequate safety culture. Also, several export licenses and monetary loans will be required. Furthermore, it will be necessary to overcome the lack of insurance for severe accidents and the anticipated USA refusal to accept domestic disposal of foreign High Level Waste (HLW). This means that government owned suppliers such as Russia have definite advantages over the USA private suppliers because of their willingness to provide loans and handling HLW. This paper first summarizes the power history growth of USA reactors and the recent momentum developed for USA SMRs; it is followed by available brief descriptions of USA LWR SMRs and some of their potential obstacles; more advanced USA SMRs designs and their potential difficulties come next; foreign applications are covered last and they are followed by a Conclusions section.


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