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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

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

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

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

Monthly Technical Progress Report

Description: Progress is reported on work on carbon reduction of uranium oxide; uranium slug and slug canning development; preparation and handling of fine non-pyrophoric uranium powder; separation of alloys; reduction of thorium oxide; and preparation of beryllium. Work to investigate and develop methods, by means of which flat plate fuel elements approximately 14 feet long can be manufactured economically by powder metallurgical processes and to investigate methods for producing tubular fuel elementsis reported. Progress is reported on work on hydrostatic pressing of metal powders and slip casting of metal powders. Further development work is reported on dimensionally stable uranium alloys, wire fuel elements, and perforated wafer fuel elements, as well as investigation of the mechanism of dimensional instability of U under irradiation and the fundamentals of sintering and of diffusional bonding.
Date: September 13, 1955
Partner: UNT Libraries Government Documents Department

Reactivity Initiated Accident Test Series RIA Scoping Test Experiment Predictions

Description: The Reactivity 'Initiated Accident (RIA) test series to be conducted in the Power Burst Facility (PBF) has been designed.to determine fuel failure thresholds, modes, and consequences as a function of energy deposition, irradiation history, and fuel design. The RIA Scoping Test will be comprised of five single unirradiated rod sub-tests. The first rod will be subjected to a series of transient power bursts of increasing energy release to determine the energy deposition at cladding failure. The second and third rods will be subjected to energy depositions near that which caused failure of the first rod, to further define the failure threshold. Rods four and five will be subjected to large radially averaged energy depositions, 1990 and 2510 J/g respectively, to investigate facility safety concerns. Several analyses were performed to predict test fuel rod and system behavior during the five RIA Scoping Test phases. A reactor physics analysis was performed to obtain the relationship between test fuel rod and reactor core energy during a power transient. The calculations were made with the RAFFLE computer code. The thermal-hydraulic behavior of the test rod coolant was investigated for pellet surface energy depositions of 900, 1125, and 1350 J/g for the first three phases of the Scoping Test. The RELAP4 computer code was used for these thermal-hydraulic analyses. The results of the RELAP4 calculations provided input to the FRAP-T4 computer code for three fuel rod behavior analyses at pellet surface energy depositions of 815, 1020, and 1225 J/g. A cladding embrittlement analysis, using the results of the FRAP-T4 calculations as input, was made to investigate the cladding oxidation mode of rod failure for the lower energy phases. BUILD5 was the analytical tool used in this investigation. Finally, the pressure pulses generated as a result of failure of the test fuel rods in the final ...
Date: June 1978
Creator: Semken, R. S.; Eaton, A. M.; Smith, R. H. & Resch, S. C.
Partner: UNT Libraries Government Documents Department

Reactivity Initiated Accident Test Series RIA Scoping Test Quick Look Report

Description: The Reactivity Initiated Accident Scoping Test (RIA-ST) was successfully completed August 30, 1978. The test was introductory to the RIA Series 1 tests and was designed to investigate and resolve several anticipated problem areas prior to performance of the first test of the series, Test RIA 1-1. The RIA Scoping Test, as performed, consisted of four separate single-rod experiment phases. The first three phases were performed with shrouded fuel rods of 5.8 wt.% enrichment. They were subjected to power bursts resulting in total fuel surface energies ranging from 205 to 261 cal/q at the axial peak elevation. The fourth phase consisted of a 20 wt.% enriched, shrouded fuel rod which was subjected to a power hurst that deposited a total radially averaged energy of 527 cal/g. The primary objectives of the Scoping Test were defined as follows: (1) Determine the applicability of extrapolating low-power steady state calorimetric measurements and self-powered neutron detector (SPND) output to determine fuel rod energy depositions during a power burst. (2) Determine the enerqy deposition failure threshold for unirradiated fuel rods at BWR hot-startup coolant conditions. (3) Determine the magnitudes of oossible pressure pulses resulting from rod failure. (4) Determine the sensitivity of the test instrumentation to high transient radiation exposures. In general, the energy deposition values for the Scoping Test derived from the SPND output were 25% higher than those obtained from the core ion chamber data. Determining which values are correct will require radiochemical analysis of the fuel rods which will take several months. At present, it apoears that the SPND derived energies are in error because of excellent agreement between the calculated and measured power calibration results and the agreement between the predicted failure threshold and that seen using the core ion chamber derived energies. Meeting the second objective was accomplished during the ...
Date: September 1978
Creator: Martinson, Z. R.; Semken, R. S.; Inabe, T.; Smith, R. H.; Cook, T. F. & Appelhans, A. D.
Partner: UNT Libraries Government Documents Department

Radon Diffusion Through Uranium Mill Tailings and Cover Defects

Description: Research was conducted at Pacific Northwest Laboratory to define the effects of cover defects on the emission of radon gas from covered uranium mill tailings piles. This report describes the results from the analysis of four geometrically simplified cover defects.
Date: December 1, 1981
Creator: Mayer, D. W. & Zimmerman, D. A.
Partner: UNT Libraries Government Documents Department

Review of Design Approaches Applicable to Dewatering Uranium Mill Tailings Disposal Pits

Description: This report is a review of design approaches in the literature that may be applicable to uranium mill tailings drainage. Tailings dewatering is required in the deep mined-out pits used for wet tailings disposal. Agricultural drainage theory is reviewed because it is seen as the most applicable technology. It is concluded that the standard drain-pipe envelope design criteria should be easily adapted. The differences in dewatering objectives and physical characteristics between agricultural and tailings drainage systems prevent direct technology transfer with respect to drain spacing calculations. Recommendations for further research are based on the drainage features unique to uranium mill tailings. It is recommended that transient solutions be applied to describe liquid movement through saturated and partially saturated tailings. Modeling should be used to evaluate the benefits of drainage design approaches after careful consideration of potential construction problems.
Date: March 1, 1982
Creator: Gutknecht, P. J. & Gates, T. E.
Partner: UNT Libraries Government Documents Department

Accident Generated Particulate Materials and Their Characteristics -- A Review of Background Information

Description: Safety assessments and environmental impact statements for nuclear fuel cycle facilities require an estimate of the amount of radioactive particulate material initially airborne (source term) during accidents. Pacific Northwest Laboratory (PNL) has surveyed the literature, gathering information on the amount and size of these particles that has been developed from limited experimental work, measurements made from operational accidents, and known aerosol behavior. Information useful for calculating both liquid and powder source terms is compiled in this report. Potential aerosol generating events discussed are spills, resuspension, aerodynamic entrainment, explosions and pressurized releases, comminution, and airborne chemical reactions. A discussion of liquid behavior in sprays, sparging, evaporation, and condensation as applied to accident situations is also included.
Date: May 1, 1982
Creator: Sutter, S. L.
Partner: UNT Libraries Government Documents Department