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Using Systems Analysis to Guide Fuel Cycle Development

Description: Systems Analysis is an important tool for guiding the development of an advanced fuel cycle. The process of nuclear research, development, and demonstration takes a relatively long time, and can require a significant amount of expensive testing. It is beneficial to minimize the amount of testing required, and systems analysis should be used as one of the first steps in downselecting technologies and streamlining the requirements. This paper discusses the application of systems analysis to advanced fuel cycle development, including using it is a tool for initial investigation of sets of technology options, as well for planning timelines for testing and downselection amongst sets of technology options. The use of Technology Readiness Levels (TRLs) in fuel cycle development is explained, together with the connection between TRLs and systems analysis via requirements development. TRLs applied to transmutation fuel development is used as an example; transmutation fuel development, including testing and qualification, is generally considered to be the most time-intensive process, from a technical point of view, in fuel cycle development, and can be the deciding factor in determining the shortest time possible for implementing an advanced fuel cycle. Using systems analysis to inform technology readiness levels provides a disciplined and informed process for advanced fuel cycle development.
Date: September 1, 2009
Creator: McCarthy, K. A. & Pasamehmetoglu, K. O.
Partner: UNT Libraries Government Documents Department

Final Report for the NERI Project

Description: This final report summarizes the research activities during the entire performance period of the NERI grant, including the extra 9 months granted under a no-cost time extension. Building up on the 14 quarterly reports submitted through October 2008, we present here an overview of the research accomplishments under the five tasks originally proposed in July 2004, together with citations for publications resulting from the project. The AFCI-NERI project provided excellent support for two undergraduate and 10 graduates students at the University of Michigan during a period of three years and nine months. Significant developments were achieved in three areas: (1) Efficient deterministic fuel cycle optimization algorithms both for PWR and SFR configurations, (2) Efficient search algorithm for PWR equilibrium cycles, and (3) Simplified Excel-based script for dynamic fuel cycle analysis of diverse cycles. The project resulted in a total of 8 conference papers and three journal papers, including two that will be submitted shortly. Three pending publications are attached to the report.
Date: March 31, 2009
Creator: Lee, John C.
Partner: UNT Libraries Government Documents Department

Overview of the International R&D Recycling Activities of the Nuclear Fuel Cycle

Description: Nuclear power has demonstrated over the last 30 years its capacity to produce base-load electricity at a low, predictable and stable cost due to the very low economic dependence on the price of uranium. However the management of used nuclear fuel remains the “Achilles’ Heel” of this energy source since the storage of used nuclear fuel is increasing as evidenced by the following number with 2,000 tons of UNF produced each year by the 104 US nuclear reactor units which equates to a total of 62,000 spent fuel assemblies stored in dry cask and 88,000 stored in pools. Two options adopted by several countries will be presented. The first one adopted by Europe, Japan and Russia consists of recycling the used nuclear fuel after irradiation in a nuclear reactor. Ninety six percent of uranium and plutonium contained in the spent fuel could be reused to produce electricity and are worth recycling. The separation of uranium and plutonium from the wastes is realized through the industrial PUREX process so that they can be recycled for re-use in a nuclear reactor as a mixed oxide (MOX) fuel. The second option undertaken by Finland, Sweden and the United States implies the direct disposal of used nuclear fuel into a geologic formation. One has to remind that only 30% of the worldwide used nuclear fuel are currently recycled, the larger part being stored (90% in pool) waiting for scientific or political decisions. A third option is emerging with a closed fuel cycle which will improve the global sustainability of nuclear energy. This option will not only decrease the volume amount of nuclear waste but also the long-term radiotoxicity of the final waste, as well as improving the long-term safety and the heat-loading of the final repository. At the present time, numerous countries are focusing ...
Date: October 1, 2012
Creator: Paviet-Hartmann, Patricia
Partner: UNT Libraries Government Documents Department

Fuel Cycle Analysis Framework Base Cases for the IAEA/INPRO GAINS Collaborative Project

Description: Thirteen countries participated in the Collaborative Project GAINS “Global Architecture of Innovative Nuclear Energy Systems Based on Thermal and Fast Reactors Including a Closed Fuel Cycle”, which was the primary activity within the IAEA/INPRO Program Area B: “Global Vision on Sustainable Nuclear Energy” for the last three years. The overall objective of GAINS was to develop a standard framework for assessing future nuclear energy systems taking into account sustainable development, and to validate results through sample analyses. This paper details the eight scenarios that constitute the GAINS framework base cases for analysis of the transition to future innovative nuclear energy systems. The framework base cases provide a reference for users of the framework to start from in developing and assessing their own alternate systems. Each base case is described along with performance results against the GAINS sustainability evaluation metrics. The eight cases include four using a moderate growth projection and four using a high growth projection for global nuclear electricity generation through 2100. The cases are divided into two sets, addressing homogeneous and heterogeneous scenarios developed by GAINS to model global fuel cycle strategies. The heterogeneous world scenario considers three separate nuclear groups based on their fuel cycle strategies, with non-synergistic and synergistic cases. The framework base case analyses results show the impact of these different fuel cycle strategies while providing references for future users of the GAINS framework. A large number of scenario alterations are possible and can be used to assess different strategies, different technologies, and different assumptions about possible futures of nuclear power. Results can be compared to the framework base cases to assess where these alternate cases perform differently versus the sustainability indicators.
Date: September 1, 2012
Creator: Dixon, Brent
Partner: UNT Libraries Government Documents Department

Strengthening the foundations of proliferation assessment tools.

Description: Robust and reliable quantitative proliferation assessment tools have the potential to contribute significantly to a strengthened nonproliferation regime and to the future deployment of nuclear fuel cycle technologies. Efforts to quantify proliferation resistance have thus far met with limited success due to the inherent subjectivity of the problem and interdependencies between attributes that lead to proliferation resistance. We suggest that these limitations flow substantially from weaknesses in the foundations of existing methodologies--the initial data inputs. In most existing methodologies, little consideration has been given to the utilization of varying types of inputs--particularly the mixing of subjective and objective data--or to identifying, understanding, and untangling relationships and dependencies between inputs. To address these concerns, a model set of inputs is suggested that could potentially be employed in multiple approaches. We present an input classification scheme and the initial results of testing for relationships between these inputs. We will discuss how classifying and testing the relationship between these inputs can help strengthen tools to assess the proliferation risk of nuclear fuel cycle processes, systems, and facilities.
Date: September 1, 2007
Creator: Rexroth, Paul E.; Saltiel, David H.; Rochau, Gary Eugene; Cleary, Virginia D.; Ng, Selena (AREVA NC, Paris, France); Greneche, Dominique (AREVA NC, Paris, France) et al.
Partner: UNT Libraries Government Documents Department

Software Requirements Specification Verifiable Fuel Cycle Simulation (VISION) Model

Description: The purpose of this Software Requirements Specification (SRS) is to define the top-level requirements for a Verifiable Fuel Cycle Simulation Model (VISION) of the Advanced Fuel Cycle (AFC). This simulation model is intended to serve a broad systems analysis and study tool applicable to work conducted as part of the AFCI (including costs estimates) and Generation IV reactor development studies.
Date: November 1, 2005
Creator: Shropshire, D. E. & West, W. H.
Partner: UNT Libraries Government Documents Department

Cost consideration in closing the nuclear fuel cycle

Description: This study evaluates the economic aspect of closing the nuclear fuel cycle. It compares the fuel cycle costs of the direct disposal and the self-generated recycle fuel cycles to determine the justifiable fuel-reprocessing costs. Previous fuel cycle cost studies cited the low natural uranium prices, due to soft demand, as the reason for low incentive of fuel reprocessing. This study calculated fuel- reprocessing costs as functions of the spent-fuel disposal costs and the natural uranium prices to illustrate that spent-fuel disposal economics could also play an important role in fuel reprocessing and the closing of the nuclear fuel cycle.
Date: June 1, 1998
Creator: Choi, J.S., LLNL
Partner: UNT Libraries Government Documents Department

Environmental Assessment Methodology for the Nuclear Fuel Cycle

Description: This report describes the methodology for determining where environmental control technology is required for the nuclear fuel cycle. The methodology addresses routine emission of chemical and radioactive effluents, and applies to mining, milling, conversion, enrichment, fuel fabrication, reactors (LWR and BWR) and fuel reprocessing. Chemical and radioactive effluents are evaluated independently. Radioactive effluents are evaluated on the basis of maximum exposed individual dose and population dose calculations for a 1-year emission period and a 50-year commitment. Sources of radionuclides for each facility are then listed according to their relative contribution to the total calculated dose. Effluent, ambient and toxicology standards are used to evaluate the effect of chemical effluents. First, each chemical and source configuration is determined. Sources are tagged if they exceed existirrg standards. The combined effect of all chemicals is assessed for each facility. If the additive effects are unacceptable, then additional control technology is recommended. Finally, sources and their chemicals at each facility are ranked according to their relative contribution to the ambient pollution level. This ranking identifies those sources most in need of environmental control.
Date: July 1, 1977
Creator: Brenchley, D. L.; Soldat, J. K.; McNeese, J. A. & Watson, E. C.
Partner: UNT Libraries Government Documents Department

Multilaboratory analytical quality control for the hydrochemical and stream sediment reconnaissance

Description: For the first time data received from LLL has been incorporated in the quality assurance report. LASL has indicated that their results on the water standard B2 have been consistently low. They suspect that this may be resulting from uranium plating out in the polyethylene containers. Such an observation has not been made by either ORGDP, SRL or LLL. To evaluate these suspect observations LASL has been sent two sets of standards, one set contained in teflon and the second in the usual polyethylene containers. LASL results for June will be carefully evaluated.
Date: May 31, 1978
Creator: D'Silva, A. P.; Haas, W. J., Jr. & Floyd, M. A.
Partner: UNT Libraries Government Documents Department

Radkowsky Thorium Fuel Project

Description: In the early/mid 1990’s Prof. Alvin Radkowsky, former chief scientist of the U.S. Naval Reactors program, proposed an alternate fuel concept employing thorium-based fuel for use in existing/next generation pressurized water reactors (PWRs). The concept was based on the use of a 'seed-blanket-unit' (SBU) that was a one-for-one replacement for a standard PWR assembly with a uranium-based central 'driver' zone, surrounded by a 'blanket' zone containing uranium and thorium. Therefore, the SBU could be retrofit without significant modifications into existing/next generation PWRs. The objective was to improve the proliferation and waste characteristics of the current once-through fuel cycle. The objective of a series of projects funded by the Initiatives for Proliferation Prevention program of the U.S. Department of Energy (DOE-IPP) - BNL-T2-0074,a,b-RU 'Radkowsky Thorium Fuel (RTF) Concept' - was to explore the characteristics and potential of this concept. The work was performed under several BNL CRADAs (BNL-C-96-02 and BNL-C-98-15) with the Radkowsky Thorium Power Corp./Thorium Power Inc. and utilized the technical and experimental capabilities in the Former Soviet Union (FSU) to explore the potential of this concept for implementation in Russian pressurized water reactors (VVERs), and where possible, also generate data that could be used for design and licensing of the concept for Western PWRs. The Project in Russia was managed by the Russian Research Center-'Kurchatov Institute'(RRC-KI), and included several institutes (e.g., PJSC 'Electrostal', NPO 'LUCH' (Podolsk), RIINM (Bochvar Institute), GAN RF (Gosatomnadzor), Kalininskaja NPP (VVER-1000)), and consisted of the following phases: Phase-1 ($550K/$275K to Russia): The objective was to perform an initial review of all aspects of the concept (design, performance, safety, implementation issues, cost, etc.) to confirm feasibility/viability and identify any “show-stoppers”; Phase-2 ($600K/$300K to Russia): Continued the activities initiated under Phase-1 with a focus on expanded design and safety analyses, and to address fuel fabrication and testing ...
Date: December 31, 2006
Creator: Todosow, Michael
Partner: UNT Libraries Government Documents Department

Interpretation of Tracer Surface Diffusion Experiments on UO{Sub 2} Roles of Gas and Solid Transport Processes

Description: The spreading of a tracer from an enriched needle source which contacts the surface of a depleted pellet sink is analyzed rigorously. It is shown that volume diffusion in both the needle and the pellet need to be considered because only by this process is sufficient radioactivity accumulated for measurement after the anneal. Parasitic gas phase processes are of two types-evaporative loss of solid if a flowing gas is used, or molecular diffusion from enriched portions of the surface to depleted zones if the couple is in a closed vessel with a stagnant gas. A complete numerical solution including surface diffusion, solid diffusion, evaporative loss and contact resistance is applied to the UO{sub 2} tracer study of Marlowe and Kazanoff at 1915° C. Based upon UO{sub 2} evaporation experiments, the analysis shows that the evaporative loss effect is not important in these experiments. The UO{sub 2} surface diffusion coefficient deduced from analysis of these data is 0.2{+-} 0.1 cm{sup 2)/s at 1915{degrees}C., which is 10{sup 4} times larger than that predicted by extrapolation of values obtained by mass transfer techniques.
Date: June 1, 1980
Creator: Olander, D. R.
Partner: UNT Libraries Government Documents Department

Preliminary Outline for Book: Engineering for Nuclear Reactor Fuel Reprocessing

Description: This document outlines a book on the subject of reactor fuel reprocessing that is still in the planning stages, representing the authors' thinking as of the arbitrary cut-off date of October 15, 1957. The subject matter that was intended for inclusion was: special considerations in radiochemical processing; chemical processes and operations; mechanical operations; fluid flow; heat transfer operations; solvent extraction; other mass diffusion operations; instrumentation; auxiliary equipment; plant design and operation; and fuel processing economics.
Date: November 15, 1957
Creator: Long, J.T.; Carter, W.L. & Rom, A.M.
Partner: UNT Libraries Government Documents Department

Ab Initio Enhanced calphad Modeling of Actinide-Rich Nuclear Fuels

Description: The process of fuel recycling is central to the Advanced Fuel Cycle Initiative (AFCI), where plutonium and the minor actinides (MA) Am, Np, and Cm are extracted from spent fuel and fabricated into new fuel for a fast reactor. Metallic alloys of U-Pu-Zr-MA are leading candidates for fast reactor fuels and are the current basis for fast spectrum metal fuels in a fully recycled closed fuel cycle. Safe and optimal use of these fuels will require knowledge of their multicomponent phase stability and thermodynamics (Gibbs free energies). In additional to their use as nuclear fuels, U-Pu-Zr-MA contain elements and alloy phases that pose fundamental questions about electronic structure and energetics at the forefront of modern many-body electron theory. This project will validate state-of-the-art electronic structure approaches for these alloys and use the resulting energetics to model U-Pu-Zr-MA phase stability. In order to keep the work scope practical, researchers will focus on only U-Pu-Zr-{Np,Am}, leaving Cm for later study. The overall objectives of this project are to: Provide a thermodynamic model for U-Pu-Zr-MA for improving and controlling reactor fuels; and, Develop and validate an ab initio approach for predicting actinide alloy energetics for thermodynamic modeling.
Date: October 28, 2013
Creator: Morgan, Dane & Yang, Yong Austin
Partner: UNT Libraries Government Documents Department

Power Reactor Fuel Reprocessing: Mechanical Phase

Description: The major events in·the.mechanical phase of the Power Reactor fuels reprocessing program during May. were: 1. Detailed design of the equipment necessary for the SRE fuel element reprocessing continues with some items released for fabrication. 2. Decision was reached to plan to start installation of equipment in the segmenting facility July 1. 3. Most SRE fuel element reprocessing equipment will be installed directly in the segmenting facility without prior testing in Building. 4505.
Date: June 1, 1959
Creator: Klima, B. B.
Partner: UNT Libraries Government Documents Department

Power Reactor Fuel Reprocessing: Mechanical Phase

Description: The major events in the mechanical phase of the Power Reactor fuels reprocessing program during June were: 1. Feasibility of shearing of fuel elements without disassembly has been demonstrated in tests using porcelain-loaded prototype fuel elements. 2. Further work with the Manco shear was not deemed tb be advisable since permission has been granted to use another shear for cutting UO{sub 2}-loaded fuel elements. 3. Necessity to strip the windows in Building 3048, to sandblast, and repaint them has seriously disrupted occupancy of the cell by July 1. Start of installation probably will not be before August 1. 4. A cold SRE element should be received during July which will permit a direct look a t the problems associated with processing of these irradiated fuel elements. 5. Concurrence with AEC, Atomics International, and ORNL people on the fabrication of a poisoned carrier was obtained and all criteria for the carrier were released and the design was completed. 6. A decision was made to install and use a 24-inch Ty-Sa-Man saw which is on hand and was originally purchased for use in the Segmenting Facility for the SRE reprocessing. This will be used instead of the multipurpose saw to allow more time to refine the design of that saw. The multipurpose saw will be installed for use in subsequent reprocessing programs. This report will chronicle the changes in status which occurred during the calendar month of June. A complete description of each item is not included and may be found in the parent report. The dates indicated on the schedule have slipped since the last report primarily due to increase in scope of the work and postponement on all phases of the work except for the SRE preparations. Twenty-four new items have been added to the schedule. The status of procurement ...
Date: July 1, 1959
Creator: Klima, B. B.
Partner: UNT Libraries Government Documents Department

Quantify Water Extraction by TBP/Dodecane via Molecular Dynamics Simulations

Description: The purpose of this project is to quantify the interfacial transport of water into the most prevalent nuclear reprocessing solvent extractant mixture, namely tri-butyl- phosphate (TBP) and dodecane, via massively parallel molecular dynamics simulations on the most powerful machines available for open research. Specifically, we will accomplish this objective by evolving the water/TBP/dodecane system up to 1 ms elapsed time, and validate the simulation results by direct comparison with experimentally measured water solubility in the organic phase. The significance of this effort is to demonstrate for the first time that the combination of emerging simulation tools and state-of-the-art supercomputers can provide quantitative information on par to experimental measurements for solvent extraction systems of relevance to the nuclear fuel cycle. Results: Initially, the isolated single component, and single phase systems were studied followed by the two-phase, multicomponent counterpart. Specifically, the systems we studied were: pure TBP; pure n-dodecane; TBP/n-dodecane mixture; and the complete extraction system: water-TBP/n-dodecane two phase system to gain deep insight into the water extraction process. We have completely achieved our goal of simulating the molecular extraction of water molecules into the TBP/n-dodecane mixture up to the saturation point, and obtained favorable comparison with experimental data. Many insights into fundamental molecular level processes and physics were obtained from the process. Most importantly, we found that the dipole moment of the extracting agent is crucially important in affecting the interface roughness and the extraction rate of water molecules into the organic phase. In addition, we have identified shortcomings in the existing OPLS-AA force field potential for long-chain alkanes. The significance of this force field is that it is supposed to be optimized for molecular liquid simulations. We found that it failed for dodecane and/or longer chains for this particular solvent extraction application. We have proposed a simple way to circumvent ...
Date: May 16, 2013
Creator: Khomami, Bamin; Cui, Shengting; de Almeida, Valmor F. & Felker, Kevin
Partner: UNT Libraries Government Documents Department

Development Plan for the Fuel Cycle Simulator

Description: The Fuel Cycle Simulator (FCS) project was initiated late in FY-10 as the activity to develop a next generation fuel cycle dynamic analysis tool for achieving the Systems Analysis Campaign 'Grand Challenge.' This challenge, as documented in the Campaign Implementation Plan, is to: 'Develop a fuel cycle simulator as part of a suite of tools to support decision-making, communication, and education, that synthesizes and visually explains the multiple attributes of potential fuel cycles.'
Date: September 1, 2011
Creator: Dixon, Brent
Partner: UNT Libraries Government Documents Department