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1

Corrosion Evaluation of RERTR Uranium Molybdenum Fuel  

International Nuclear Information System (INIS)

As part of the National Nuclear Security Agency (NNSA) mandate to replace the use of highly enriched uranium (HEU) fuel for low enriched uranium (LEU) fuel, research into the development of LEU fuel for research reactors has been active since the late 1970's. Originally referred to as the Reduced Enrichment for Research and Test Reactor (RERTR) program the new effort named Global Threat Reduction Initiative (GTRI) is nearing the goal of replacing the standard aluminum clad dispersion highly enriched uranium aluminide fuel with a new LEU fuel. The five domestic high performance research reactors undergoing this conversion are High Flux Isotope reactor (HFIR), Advanced Test Reactor (ATR), National Institute of Standards and Technology (NIST) Reactor, Missouri University Research Reactor (MURR) and the Massachusetts Institute of Technology Reactor II (MITR-II). The design of these reactors requires a higher neutron flux than other international research reactors, which to this point has posed unique challenges in the design and development of the new mandated LEU fuel. The new design utilizes a monolithic fuel configuration in order to obtain sufficient 235U within the LEU stoichoimetry to maintain the fission reaction within the domestic test reactors. The change from uranium aluminide dispersion fuel type to uranium molybdenum (UMo) monolithic configuration requires examination of possible corrosion issues associated with the new fuel meat. A focused analysis of the UMew fuel meat. A focused analysis of the UMo fuel under potential corrosion conditions, within the ATR and under aqueous storage indicates a slow and predictable corrosion rate. Additional corrosion testing is recommended for the highest burn-up fuels to confirm observed corrosion rate trends. This corrosion analysis will focus only on the UMo fuel and will address corrosion of ancillary components such as cladding only in terms of how it affects the fuel. The calculations and corrosion scenarios are weighted with a conservative bias to provide additional confidence with the results. The actual corrosion rates of UMo fuel is very likely to be lower than assumed within this report which can be confirmed with additional testing.

2

Corrosion Evaluation of RERTR Uranium Molybdenum Fuel  

Energy Technology Data Exchange (ETDEWEB)

As part of the National Nuclear Security Agency (NNSA) mandate to replace the use of highly enriched uranium (HEU) fuel for low enriched uranium (LEU) fuel, research into the development of LEU fuel for research reactors has been active since the late 1970’s. Originally referred to as the Reduced Enrichment for Research and Test Reactor (RERTR) program the new effort named Global Threat Reduction Initiative (GTRI) is nearing the goal of replacing the standard aluminum clad dispersion highly enriched uranium aluminide fuel with a new LEU fuel. The five domestic high performance research reactors undergoing this conversion are High Flux Isotope reactor (HFIR), Advanced Test Reactor (ATR), National Institute of Standards and Technology (NIST) Reactor, Missouri University Research Reactor (MURR) and the Massachusetts Institute of Technology Reactor II (MITR-II). The design of these reactors requires a higher neutron flux than other international research reactors, which to this point has posed unique challenges in the design and development of the new mandated LEU fuel. The new design utilizes a monolithic fuel configuration in order to obtain sufficient 235U within the LEU stoichoimetry to maintain the fission reaction within the domestic test reactors. The change from uranium aluminide dispersion fuel type to uranium molybdenum (UMo) monolithic configuration requires examination of possible corrosion issues associated with the new fuel meat. A focused analysis of the UMo fuel under potential corrosion conditions, within the ATR and under aqueous storage indicates a slow and predictable corrosion rate. Additional corrosion testing is recommended for the highest burn-up fuels to confirm observed corrosion rate trends. This corrosion analysis will focus only on the UMo fuel and will address corrosion of ancillary components such as cladding only in terms of how it affects the fuel. The calculations and corrosion scenarios are weighted with a conservative bias to provide additional confidence with the results. The actual corrosion rates of UMo fuel is very likely to be lower than assumed within this report which can be confirmed with additional testing.

A K Wertsching

2012-09-01

3

CONCEPTUAL PROCESS DESCRIPTION FOR THE MANUFACTURE OF LOW-ENRICHED URANIUM-MOLYBDENUM FUEL  

International Nuclear Information System (INIS)

ns. The fuel design is based on a monolithic fuel meat (made from a uranium-molybdenum alloy) clad in Al-6061 that has shown excellent performance in irradiation testing. The unique aspects of the fuel design, however, necessitate the development and implementation of new fabrication techniques and, thus, establishment of the infrastructure to ensure adequate fuel fabrication capability. A conceptual fabrication process description and rough estimates of the total facility throughput are described in this document as a basis for establishing preconceptual fabrication facility designs

4

Irradiation performance of uranium-molybdenum alloy dispersion fuels  

International Nuclear Information System (INIS)

The U-Mo-Al dispersion fuels of Material Test Reactors (MTR) are analyzed in terms of their irradiation performance. The irradiation performance aspects are associated to the neutronic and thermal hydraulics aspects to propose a new core configuration to the IEA-R1 reactor of IPEN-CNEN/SP using U-Mo-Al fuels. Core configurations using U-10Mo-Al fuels with uranium densities variable from 3 to 8 gU/cm3 were analyzed with the computational programs Citation and MTRCR-IEA R1. Core configurations for fuels with uranium densities variable from 3 to 5 gU/cm3 showed to be adequate to use in IEA-R1 reactor e should present a stable in reactor performance even at high burn-up. (author)

5

CONCEPTUAL PROCESS DESCRIPTION FOR THE MANUFACTURE OF LOW-ENRICHED URANIUM-MOLYBDENUM FUEL  

Energy Technology Data Exchange (ETDEWEB)

The National Nuclear Security Agency Global Threat Reduction Initiative (GTRI) is tasked with minimizing the use of high-enriched uranium (HEU) worldwide. A key component of that effort is the conversion of research reactors from HEU to low-enriched uranium (LEU) fuels. The GTRI Convert Fuel Development program, previously known as the Reduced Enrichment for Research and Test Reactors program was initiated in 1978 by the United States Department of Energy to develop the nuclear fuels necessary to enable these conversions. The program cooperates with the research reactors’ operators to achieve this goal of HEU to LEU conversion without reduction in reactor performance. The programmatic mandate is to complete the conversion of all civilian domestic research reactors by 2014. These reactors include the five domestic high-performance research reactors (HPRR), namely: the High Flux Isotope Reactor at the Oak Ridge National Laboratory, the Advanced Test Reactor at the Idaho National Laboratory, the National Bureau of Standards Reactor at the National Institute of Standards and Technology, the Missouri University Research Reactor at the University of Missouri–Columbia, and the MIT Reactor-II at the Massachusetts Institute of Technology. Characteristics for each of the HPRRs are given in Appendix A. The GTRI Convert Fuel Development program is currently engaged in the development of a novel nuclear fuel that will enable these conversions. The fuel design is based on a monolithic fuel meat (made from a uranium-molybdenum alloy) clad in Al-6061 that has shown excellent performance in irradiation testing. The unique aspects of the fuel design, however, necessitate the development and implementation of new fabrication techniques and, thus, establishment of the infrastructure to ensure adequate fuel fabrication capability. A conceptual fabrication process description and rough estimates of the total facility throughput are described in this document as a basis for establishing preconceptual fabrication facility designs.

Daniel M. Wachs; Curtis R. Clark; Randall J. Dunavant

2008-02-01

6

Qualification of uranium-molybdenum alloy fuel - conclusions of an international workshop  

International Nuclear Information System (INIS)

Thirty-one participants representing 21 reactors, fuel developers, fuel fabricators, and fuel reprocessors in 11 countries discussed the requirements for qualification of U-MO alloy fuel at a workshop held at Argonne National Laboratory on January 17--18, 2000. Consensus was reached that the qualification plans of the US RERTR program and the French U-Mo fuel development program are valid. The items to be addressed during qualification are summarized in the paper

7

A model for recovery of scrap monolithic uranium molybdenum fuel by electrorefining  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The goal of the Reduced Enrichment for Research and Test Reactors program (RERTR) is toreduce enrichment at research and test reactors, thereby decreasing proliferation risk at these facilities. A new fuel to accomplish this goal is being manufactured experimentally at the Y12 National Security Complex. This new fuel will require its own waste management procedure,namely for the recovery of scrap from its manufacture. The new fuel is a monolithic uraniummolybdenum alloy clad in zirconium. Fea...

Kleeck, Melissa A.

2011-01-01

8

A model for recovery of scrap monolithic uranium molybdenum fuel by electrorefining  

Science.gov (United States)

The goal of the Reduced Enrichment for Research and Test Reactors program (RERTR) is toreduce enrichment at research and test reactors, thereby decreasing proliferation risk at these facilities. A new fuel to accomplish this goal is being manufactured experimentally at the Y12 National Security Complex. This new fuel will require its own waste management procedure,namely for the recovery of scrap from its manufacture. The new fuel is a monolithic uraniummolybdenum alloy clad in zirconium. Feasibility tests were conducted in the Planar Electrode Electrorefiner using scrap U-8Mo fuel alloy. These tests proved that a uranium product could be recovered free of molybdenum from this scrap fuel by electrorefining. Tests were also conducted using U-10Mo Zr clad fuel, which confirmed that product could be recovered from a clad version of this scrap fuel at an engineering scale, though analytical results are pending for the behavior of Zr in the electrorefiner. A model was constructed for the simulation of electrorefining the scrap material produced in the manufacture of this fuel. The model was implemented on two platforms, Microsoft Excel and MatLab. Correlations, used in the model, were developed experimentally, describing area specific resistance behavior at each electrode. Experiments validating the model were conducted using scrap of U-10Mo Zr clad fuel in the Planar Electrode Electrorefiner. The results of model simulations on both platforms were compared to experimental results for the same fuel, salt and electrorefiner compositions and dimensions for two trials. In general, the model demonstrated behavior similar to experimental data but additional refinements are needed to improve its accuracy. These refinements consist of a function for surface area at anode and cathode based on charge passed. Several approximations were made in the model concerning areas of electrodes which should be replaced by a more accurate function describing these areas.

Van Kleeck, Melissa A.

9

Development of a high density fuel based on uranium-molybdenum alloys with high compatibility in high temperatures  

International Nuclear Information System (INIS)

This work has as its objective the development of a high density and low enriched nuclear fuel based on the gamma-UMo alloys, for utilization where it is necessary satisfactory behavior in high temperatures, considering its utilization as dispersion. For its accomplishment, it was started from the analysis of the RERTR ('Reduced Enrichment for Research and Test Reactors') results and some theoretical works involving the fabrication of gamma-uranium metastable alloys. A ternary addition is proposed, supported by the properties of binary and ternary uranium alloys studied, having the objectives of the gamma stability enhancement and an ease to its powder fabrication. Alloys of uranium-molybdenum were prepared with 5 to 10% Mo addition, and 1 and 3% of ternary, over a gamma U7Mo binary base alloy. In all the steps of its preparation, the alloys were characterized with the traditional techniques, to the determination of its mechanical and structural properties. To provide a process for the alloys powder obtention, its behavior under hydrogen atmosphere were studied, in thermo analyser-thermo gravimeter equipment. Temperatures varied from the ambient up to 1000 deg C, and times from 15 minutes to 16 hours. The results validation were made in a semi-pilot scale, where 10 to 50 g of powders of some of the alloys studied were prepared, under static hydrogen atmosphere. Compatibility studies were conducted by the exposure of the alloys under oxygen and aluminum, to the verification of possible reactions by means of differential thermal analysis. The alloys were exposed to a constant heat up to 1000 deg C, and their performances were evaluated in terms of their reaction resistance. On the basis of the results, it was observed that ternary additions increases the temperatures of the reaction with aluminum and oxidation, in comparison with the gamma UMo binaries. A set of conditions to the hydration of the alloys were defined, more restrictive in terms of temperature, time and pre-treatment to stabilize the gamma structure. The addition of a bit low ternary excess and formation of an intergranular phase, the increase in stability, it was demonstrated that there is not a damage in the formation of their powders.(author)

10

Irradiation performance of uranium-molybdenum alloy dispersion fuels; Desempenho sob irradiacao de elementos combustiveis do tipo U-Mo  

Energy Technology Data Exchange (ETDEWEB)

The U-Mo-Al dispersion fuels of Material Test Reactors (MTR) are analyzed in terms of their irradiation performance. The irradiation performance aspects are associated to the neutronic and thermal hydraulics aspects to propose a new core configuration to the IEA-R1 reactor of IPEN-CNEN/SP using U-Mo-Al fuels. Core configurations using U-10Mo-Al fuels with uranium densities variable from 3 to 8 gU/cm{sup 3} were analyzed with the computational programs Citation and MTRCR-IEA R1. Core configurations for fuels with uranium densities variable from 3 to 5 gU/cm{sup 3} showed to be adequate to use in IEA-R1 reactor e should present a stable in reactor performance even at high burn-up. (author)

Almeida, Cirila Tacconi de

2005-07-01

11

Set up of Uranium-Molybdenum powder production (HMD process)  

International Nuclear Information System (INIS)

Powder metallurgy offers different alternatives for the production of Uranium-Molybdenum (UMo) alloy powder in sizes smaller than 150 microns. This powder is intended to be used as a dispersion fuel in an aluminum matrix for research, testing and radioisotopes production reactors (MTR). A particular process of massive hydriding the UMo alloy in gamma phase has been developed. This work describes the final adjustments of process variables to obtain UMo powder by hydriding-milling-de hydriding (HMD) and its capability for industrial scaling up. (author)

12

Spectrographic analysis of uranium-molybdenum alloys  

International Nuclear Information System (INIS)

A spectrographic method of analysis has been developed for uranium-molybdenum alloys containing up to 10 % Mo. The carrier distillation technique, with gallium oxide and graphite as carriers, is used for the semiquantitative determination of Al, Cr, Fe, Ni and Si, involving the conversion of the samples into oxides. As a consequence of the study of the influence of the molybdenum on the line intensities, it is useful to prepare only one set of standards with 0,6 % MoO3. Total burning excitation is used for calcium, employing two sets of standards with 0,6 and 7.5 MoO3. (Author) 5 refs

13

Qualification of Uranium-Molybdenum Alloys for Research Reactor Community  

Energy Technology Data Exchange (ETDEWEB)

Uranium-molybdenum (U-Mo) alloys are being produced to refuel international research reactors - replacing current highly-enriched uranium fuel assemblies. Over the past two years, Y-12 Analytical Chemistry has been the primary qualification laboratory for current U-Mo materials development in the U.S. During this time, multiple analytical techniques have been explored to obtain complete and accurate characterization of U-Mo materials. For the chemical characterization of U-Mo materials, three primary techniques have been utilized: (i) thermal ionization mass spectrometry (TIMS) for uranium content and isotopic analyses, (ii) a combination of inductively-coupled plasma (ICP) techniques for determination of molybdenum content and trace elemental concentrations and (iii) combustion analyses for trace elemental analyses. Determination of uranium content, uranium isotopic composition and elemental impurities by combustion analyses (H, C, O, N) required only minimal changes to existing analytical methodology for uranium metal analyses. However, spectral interferences (both isobaric and optical) due to high molybdenum content presented significant challenges to the use of ICP instrumentation. While providing a brief description of methods for determination of uranium content and H, C, O and N content, this manuscript concentrates on the challenges faced in applying ICP techniques to qualification of U-Mo fuels. Multiple ICP techniques were explored to determine the effectiveness (e.g., accuracy, precision, speed of analysis, etc.) for determining both molybdenum content and trace elemental impurity concentrations: high-resolution inductively-coupled plasma mass spectrometry (HR-ICPMS), inductively- coupled plasma quadrupole mass spectrometry (ICP-QMS) and inductively-coupled plasma optical emission spectroscopy (ICP-OES). The merits and limitations of these techniques for qualification of U-Mo alloys are presented, to include the limits of quantitation and uncertainties of measurements regarding the most efficient methods for qualifying the U-Mo alloys. (author)

Schaaff, T.G.; Belt, V.F.; Likens, A.M.; Joyce, K.E.; Barry, J.F. [Analytical Chemistry Organization, Y-12 National Security Complex, Oak Ridge, Tennessee 37831 (United States)

2011-07-01

14

Application of ion exchange technology to the dump leaching of hydrothermal volcanic uranium-molybdenum ore  

International Nuclear Information System (INIS)

Taking Shangmajiazi hydrothermal volcanic type uranium-molybdenum ore dump leaching as an example, this paper expounds the principle and application of ion exchange technology employed in extracting uranium from leaching liquor, compares two kinds leaching liquor, and briefly presents mechanism and treatment of the poisoning of resin molybdenum. All these are significant for developing similar ore-deposit. (authors)

15

Study and comparison of analytical methods for dosing molybdenum in uranium-molybdenum alloys  

International Nuclear Information System (INIS)

Methods to determine molybdenum in uranium-molybdenum alloys are developed by various technic: molecular absorption spectrophotometry, emission spectroscopy, X ray fluorescence, atomic absorption spectrophotometry. After a comparison on samples in which molybdenum content lies between 1 and 10 per cent by weight, one concludes in the interest of some of the exposed methods for routine analysis. (author)

16

Environmental impact study report, Ben Lomond uranium-molybdenum project, Northern Queensland  

International Nuclear Information System (INIS)

A significant uranium-molybdenum mineralisation has been discovered in Northern Queensland, west of Townsville. Granting of a mining lease is subject to the compilation and acceptance of an environmental impact study report. The report describes the proposed mining and milling project, the existing environment and the impact of the proposal on the environment. Two main environmental safeguards incorporated into the project are a comprehensive water management scheme and a progressive site rehabilitation

17

Spectrographic analysis of uranium-molybdenum alloys; Analisis espectrografico de aleaciones uranio-molibdeno  

Energy Technology Data Exchange (ETDEWEB)

A spectrographic method of analysis has been developed for uranium-molybdenum alloys containing up to 10 % Mo. The carrier distillation technique, with gallium oxide and graphite as carriers, is used for the semiquantitative determination of Al, Cr, Fe, Ni and Si, involving the conversion of the samples into oxides. As a consequence of the study of the influence of the molybdenum on the line intensities, it is useful to prepare only one set of standards with 0,6 % MoO{sub 3}. Total burning excitation is used for calcium, employing two sets of standards with 0,6 and 7.5 MoO{sub 3}. (Author) 5 refs.

Roca, M.

1967-07-01

18

SASSE MODELING OF A URANIUM MOLYBDENUM SEPARATION FLOWSHEET  

International Nuclear Information System (INIS)

H-Canyon Engineering (HCE) is evaluating the feasibility of processing material from the Super Kukla Prompt Burst Reactor, which operated at the Nevada Test Site from 1964 to 1978. This material is comprised of 90 wt % uranium (U) (at approximately 20% 235U enrichment) alloyed with 10 wt % molybdenum (Mo). The objective is to dissolve the material in nitric acid (HNO3) in the H-Canyon dissolvers and then to process the dissolved material through H-Canyon First and Second Cycle solvent extraction. The U product from Second Cycle will be sent to the highly enriched uranium (HEU) blend down program. In the blend down program, enriched U from the 1EU product stream will be blended with natural U at a ratio of 1 part enriched U per 3.5 parts natural U to meet a reactor fuel specification of 4.95% 235U before being shipped for use by the Tennessee Valley Authority (TVA) in its nuclear plants. The TVA specification calls for 3 concentrations for aluminum nitrate (Al(NO3))3 in the feed to 1A Bank. (Unlike Savanah River Site (SRS) fuels, the U/Mo material contains no aluminum (Al). As a result, higher HNO3 concentrations are required in the 1AF to provide the necessary salting.) The TVA limit for the final blended product is 200 (micro)g Mo/g U, which translates to approximately 800 mg Mo/g U for the Second Cycle product solution. SASSE calculations give a Mo impurity level of 4 (micro)g Mo/g U in the Second Cycle product solution, conservatively based on Mo organic-to-aqueous distributions measured during minibank testing for previous processing of Piqua reactor fuel. The calculated impurity level is slightly more than two orders of magnitude lower than the required level. The Piqua feed solution contained a significant concentration of Al(NO3)3, which is not present in the feed solution for the proposed flowsheet. Measured distribution data indicate that, without Al(NO3)3 or other salting agents present, Mo extracts into the organic phase to a much lesser extent, so that the overall U/Mo separation is better and the Mo impurities in the Second Cycle product drop to negligible concentrations. The 1DF U concentration of 20 g/L specified by the proposed flowsheet requires an increased 1DX organic feed rate to satisfy H-Canyon Double Contingency Analysis (DCA) guidelines for the prevention of U refluxing. The ranges for the 1AX, 1BS, and 1DX organic flow rates in the proposed flowsheet are set so that the limiting ratios of organic/aqueous flow rates exactly meet the minimum values specified by the DCA

19

Relationship between uranium-molybdenum, fluorite and gold deposits within provinces of continental volcanicity  

International Nuclear Information System (INIS)

The article gives a comparative description of and the age relationships between uranium-molybdenum, gold and fluorite mineralizations in the areas of development of adhesite-diorite and liparite-granite vulcanoplutonic formations, which are most fully and intensively manifest in the intra-anticlinal and median blocks of folded regions in the final stages of geosynclinal development or during the final stages of tectono-magmatic activation. These formations usually fill vulcano-tectonic depression structures - overlaid troughs and inherited delections. The geological and geochemical data are evidence of the close temporal link between the hydrothermal process of ore formation and the type and scale of manifestations of the vulcano-plutonic magmatism that is responsible for the general geochemical features of the ores of deposits of various types. The formation of gold, fluorite and uranium-molybdenum deposits occurred immediately after the completion of effusive and intrusive magmatism during a single metallogenic cycle. The spatial distribution of the ore fields and deposits depends chiefly on the peculiarities of the tectonic make-up of the depression structures, and also on the type and scale of the manifestations of vulcano-plutonic magmatism. (B.Ya.)

20

A study of phase transformations processes in 0,5 to 4% mo uranium-molybdenum alloys  

International Nuclear Information System (INIS)

Isothermal and continuous cooling transformations process have been established on uranium-molybdenum alloys containing 0,5 to 4 w% Mo. Transformations process of the ? and ? solid solutions are described. These processes depend upon molybdenum concentration. Out of the ? solid solution phase appears an eutectoid decomposition of ? to (? + ?) or the formation of a martensitic phase ?''. The ? solid solution shows a decomposition of ? to (? + ?) or (? + ?'), or a formation of martensitic phases a' or a'b. The U-Mo equilibrium diagram is discussed, particularly in low concentrations zones. Limits between domains (? + ?) and (? + ?), (? + ?) and ?, (? + ?) and ?, have been determined. (author)

 
 
 
 
21

Obtention of uranium-molybdenum alloy ingots technique to avoid carbon contamination  

Energy Technology Data Exchange (ETDEWEB)

The replacement of high enriched uranium (U{sup 235} > 85 wt%) by low enriched uranium (U{sup 235} < 20wt%) nuclear fuels in research and test reactors is being implemented as an initiative of the Reduced Enrichment for Research and Test Reactors (RERTR) program, conceived in the USA since mid-70s, in order to avoid nuclear weapons proliferation. Such replacement implies in the use of compounds or alloys with higher uranium densities. Among the several uranium alloys investigated since then, U-Mo presents great application potential due to its physical properties and good behavior during irradiation, which makes it an important option as a nuclear fuel material for the Brazilian Multipurpose Reactor - RMB. The development of the plate-type nuclear fuel based on U-Mo alloy is being performed at the Nuclear Technology Development Centre (CDTN) and also at IPEN. The carbon contamination of the alloy is one of the great concerns during the melting process. It was observed that U-Mo alloy is more critical considering carbon contamination when using graphite crucibles. Alternative melting technique was implemented at CDTN in order to avoid carbon contamination from graphite crucible using Yttria stabilized ZrO{sub 2} crucibles. Ingots with low carbon content and good internal quality were obtained. (author)

Pedrosa, Tercio A.; Paula, Joao Bosco de; Reis, Sergio C.; Brina, Jose Giovanni M.; Faeda, Kelly Cristina M.; Ferraz, Wilmar B., E-mail: tap@cdtn.b, E-mail: jbp@cdtn.b, E-mail: jgmb@cdtn.b, E-mail: ferrazw@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2011-07-01

22

Obtention of uranium-molybdenum alloy ingots microstructure and phase characterization  

Energy Technology Data Exchange (ETDEWEB)

The replacement of high enriched uranium (U-{sup 235} > 85 wt%) by low enriched uranium (U-{sup 235} < 20 wt%) nuclear fuels in research and test reactors is being implemented as an initiative of the Reduced Enrichment for Research and Test Reactors (RERTR) program, conceived in the USA since mid-70s, in order to avoid nuclear weapons proliferation. Such replacement implies in the use of compounds or alloys with higher uranium densities. Several uranium alloys that fill this requirement has been investigated since then. Among these alloys, U-Mo presents great application potential due to its physical properties and good behavior during irradiation, which makes it an important option as a nuclear fuel material for the Brazilian Multipurpose Reactor - RMB. The development of the plate-type nuclear fuel based on U-Mo alloys is being performed at the Nuclear Technology Development Centre (CDTN) and also at the Institute of Energetic and Nuclear Research - IPEN. U-{sup 10}Mo ingots were melted in an induction furnace with protective argon atmosphere. The microstructure of the ingots were characterized through optical and scanning electronic microscopy in the as cast and heat treated conditions. Energy Dispersive Spectrometry and X-Ray Diffraction were used as characterization techniques for elemental analysis and phases determination. It was confirmed the presence of metastable gamma-phase in the as cast condition, surrounded by hypereutectoid alpha-phase (uranium-rich phase), as well as a pearlite-like constituent, composed by alternated lamellas of U{sub 2}Mo compound and alpha-phase, in the heat treated condition. (author)

Pedrosa, Tercio A.; Braga, Daniel M.; Paula, Joao Bosco de; Brina, Jose Giovanni M.; Ferraz, Wilmar B., E-mail: tap@cdtn.b, E-mail: bragadm@cdtn.b, E-mail: jbp@cdtn.b, E-mail: jgmb@cdtn.b, E-mail: ferrazw@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2011-07-01

23

Effect of formation and growth of dislocation loops and cavities on low-temperature swelling of irradiated uranium-molybdenum alloys  

International Nuclear Information System (INIS)

Scanning electron photomicrographs of U-10 wt.% Mo irradiated at low temperature in the Advanced Test Reactor (ATR) to about 40 at.% burnup show the presence of cavities. The authors have used a rate-theory-based model to investigate the nucleation and growth of cavities during low-temperature irradiation of uranium-molybdenum alloys in the presence of irradiation-induced interstitial-loop formation and growth. The calculations indicate that the swelling mechanism in the U-10 wt.% Mo alloy at low irradiation temperatures is fission-gas driven. The calculations also indicate that the observed bubbles must be associated with a subgrain structure. Calculated bubble-size-distributions are compared with irradiation data

24

UPDATE ON MONOLITHIC FUEL FABRICATION METHODS  

International Nuclear Information System (INIS)

Efforts to develop a viable monolithic research reactor fuel plate have continued at Idaho National Laboratory. These efforts have concentrated on both fabrication process refinement and scale-up to produce full sized fuel plates. Progress at INL has led to fabrication of hot isostatic pressed uranium-molybdenum bearing monolithic fuel plates. These miniplates are part of the RERTR-8 miniplate irradiation test. Further progress has also been made on friction stir weld processing which has been used to fabricate full size fuel plates which will be irradiated in the ATR and OSIRIS reactors

25

An interdiffusional model for prediction of the interaction layer growth in the system uranium-molybdenum/aluminum  

International Nuclear Information System (INIS)

The codes PLACA and DPLACA, elaborated in this working group, simulate the behavior of a plate-type fuel containing in its core a foil of monolithic or dispersed fissile material, respectively, under normal operation conditions of a research reactor. Dispersion fuels usually consist of ceramic particles of a uranium compound in a high thermal conductivity matrix. The use of particles of a U-Mo alloy in a matrix of Al requires especially devoted subroutines able to simulate the growth of the interaction layer that develops between the particles and the matrix. A model is presented in this work that gives account of these particular phenomena. It is based on the assumption that diffusion of U and Al through the layer is the rate-determining step. Two moving interfaces separate the growing reaction layer from the original phases. The kinetics of these boundaries are solved as Stefan problems. In order to test the model and the associated code, some previous, simpler problems corresponding to similar systems for which analytical solutions or experimental data are known were simulated. Experiments performed with planar U-Mo/Al diffusion couples are reported in the literature, which purpose is to obtain information on the system parameters. These experiments were simulated with PLACA. Results of experiments performed with U-Mo particles disperse in Al either without or with irradiation, published in the open literature were simulated with DPLACA. A satisfactory prediction od with DPLACA. A satisfactory prediction of the whole reaction layer thickness and of the individual fractions corresponding to alloy and matrix consumption was obtained

26

Development and Validation of Capabilities to Measure Thermal Properties of Layered Monolithic U-Mo Alloy Plate-Type Fuel  

Science.gov (United States)

The uranium-molybdenum (U-Mo) alloy in a monolithic form has been proposed as one fuel design capable of converting some of the world's highest power research reactors from the use of high enriched uranium to low enriched uranium. One aspect of the fuel development and qualification process is to demonstrate appropriate understanding of the thermal-conductivity behavior of the fuel system as a function of temperature and expected irradiation conditions. The purpose of this paper is to verify functionality of equipment installed in hot cells for eventual measurements on irradiated uranium-molybdenum (U-Mo) monolithic fuel specimens, refine procedures to operate the equipment, and validate models to extract the desired thermal properties. The results presented here demonstrate the adequacy of the equipment, procedures, and models that have been developed for this purpose based on measurements conducted on surrogate depleted uranium-molybdenum (DU-Mo) alloy samples containing a Zr diffusion barrier and clad in aluminum alloy 6061 (AA6061). The results are in excellent agreement with thermal property data reported in the literature for similar U-Mo alloys as a function of temperature.

Burkes, Douglas E.; Casella, Andrew M.; Buck, Edgar C.; Casella, Amanda J.; Edwards, Matthew K.; MacFarlan, Paul J.; Pool, Karl N.; Smith, Frances N.; Steen, Franciska H.

2014-07-01

27

Complex plasmochemical processing of solid fuel  

Directory of Open Access Journals (Sweden)

Full Text Available Technology of complex plasmaochemical processing of solid fuel by Ecibastuz bituminous and Turgay brown coals is presented. Thermodynamic and experimental study of the technology was fulfilled. Use of this technology allows producing of synthesis gas from organic mass of coal and valuable components (technical silicon, ferrosilicon, aluminum and silicon carbide and microelements of rare metals: uranium, molybdenum, vanadium etc. from mineral mass of coal. Produced a high-calorific synthesis gas can be used for methanol synthesis, as high-grade reducing gas instead of coke, as well as energy gas in thermal power plants.

Vladimir Messerle

2012-12-01

28

Design and Testing of Prototypic Elements Containing Monolithic Fuel  

International Nuclear Information System (INIS)

The US fuel development team has performed numerous irradiation tests on small to medium sized specimens containing low enriched uranium fuel designs. The team is now focused on qualification and demonstration of the uranium-molybdenum Base Monolithic Design and has entered the next generation of testing with the design and irradiation of prototypic elements which contain this fuel. The designs of fuel elements containing monolithic fuel, such as AFIP-7 (which is currently under irradiation) and RERTR-FE (which is currently under fabrication), are appropriate progressions relative to the technology life cycle. The culmination of this testing program will occur with the design, fabrication, and irradiation of demonstration products to include the base fuel demonstration and design demonstration experiments. Future plans show that design, fabrication, and testing activities will apply the rigor needed for a demonstration campaign.

29

Design and Testing of Prototypic Elements Containing Monolithic Fuel  

Energy Technology Data Exchange (ETDEWEB)

The US fuel development team has performed numerous irradiation tests on small to medium sized specimens containing low enriched uranium fuel designs. The team is now focused on qualification and demonstration of the uranium-molybdenum Base Monolithic Design and has entered the next generation of testing with the design and irradiation of prototypic elements which contain this fuel. The designs of fuel elements containing monolithic fuel, such as AFIP-7 (which is currently under irradiation) and RERTR-FE (which is currently under fabrication), are appropriate progressions relative to the technology life cycle. The culmination of this testing program will occur with the design, fabrication, and irradiation of demonstration products to include the base fuel demonstration and design demonstration experiments. Future plans show that design, fabrication, and testing activities will apply the rigor needed for a demonstration campaign.

N.E. Woolstenhulme; M.K. Meyer; D.M. Wachs

2011-10-01

30

Contribution to the study of remedy solutions to uranium(molybdenum)/aluminium interactions: role of silicon addition to aluminium, study of coupled effects  

International Nuclear Information System (INIS)

In the project development and qualification program of a nuclear fuel with Low Enriched Uranium for Materials Testing Reactors, the dispersed U(Mo)/Al fuel is being developed due to its excellent stability during irradiation. However, in pile experiments showed that depending on the irradiation conditions (e.g. high burnup or high heat flux), an extensive interaction occurs between the fissile element U(Mo) and the Al based matrix resulting in swelling, which could eventually lead to a fuel plate failure. Among the ways to improve the behavior of the dispersed U(Mo) fuel, the solution now seen as the reference remedy by the entire scientific community is the addition of silicon into the aluminum matrix. In order to provide some understanding and optimizing the solution 'Si additions into Al matrix' under neutron irradiation, an out of pile study is performed on (i) the interaction mechanisms involved in the U(Mo)/Al (Si) system and (ii) the impact of the Si additions into the Al matrix on alternative solutions to the U(Mo)/Al interactions, namely the modification of the ?-U(Mo) fissile compound by adding a third element and/or modifying the interface between the ?-U(Mo) fissile compound and the matrix. This document provides a mechanistic description of the U(7Mo)/Al(Si) interaction for a range of Si content in Al between 2 and 10 wt.%, based on the multi-scale characterization of diffusion couples. The location of the Mo and its role in the reaction mechanisms are demonstrated. The influence of elements X = Y, Cu, Zr, Ti, Cr, on the U (Mo)/Al and U (Mo)/Al (Si) interactions mechanisms was then studied. It is shown that adding a third element to the U(Mo) alloy acts on the second order on diffusion kinetics and (micro)structure of the interaction layer compared to the addition of Si into Al. Finally, an alumina coating which shows a potential interest to improve the performance of the fuel has been developed. (author)

31

The reprocessing of irradiated fuels improvement and extension of the solvent extraction process  

International Nuclear Information System (INIS)

Improvements made in the conventional tri-butylphosphate process are described, in particular. the concentration and the purification of plutonium by one extraction cycle using tri-butyl-phosphate with reflux; and the use of an apparatus working continuously for precipitating plutonium oxalate, for calcining the oxalate, and for fluorinating the oxide. The modifications proposed for the treatment of irradiated uranium - molybdenum alloys are described, in particular, the dissolution of the fuel, and the concentration of the fission product solutions. The solvent extraction treatment is used also for the plutonium fuels utilized for the fast breeder reactor (Rapsodie) An outline of the process is presented and discussed, as well as the first experimental results and the plans for a pilot plant having a capacity of 1 kg/day. The possible use of tn-lauryl-amine in the plutonium purification cycle is now under consideration for the processing plant at La Hague. The flowsheet for this process and its performance are presented. The possibility of vitrification is considered for the final treatment of the concentrated radioactive wastes from the Marcoule (irradiated uranium) and La Hague (irradiated uranium-molybdenum) Centers. Three possible processes are described and discussed, as well as the results obtained from the operation of the corresponding experimental units using tracers. (authors)

32

A cellular automaton method to simulate the microstructure and evolution of low-enriched uranium (LEU) U-Mo/Al dispersion type fuel plates  

Science.gov (United States)

Low-enriched uranium (LEU) fuel plates for high power materials test reactors (MTR) are composed of nominally spherical uranium-molybdenum (U-Mo) particles within an aluminum matrix. Fresh U-Mo particles typically range between 10 and 100 ?m in diameter, with particle volume fractions up to 50%. As the fuel ages, reaction-diffusion processes cause the formation and growth of interaction layers that surround the fuel particles. The growth rate depends upon the temperature and radiation environment. The cellular automaton algorithm described in this paper can synthesize realistic random fuel-particle structures and simulate the growth of the intermetallic interaction layers. Examples in the present paper pack approximately 1000 particles into three-dimensional rectangular fuel structures that are approximately 1 mm on each side. The computational approach is designed to yield synthetic microstructures consistent with images from actual fuel plates and is validated by comparison with empirical data on actual fuel plates.

Drera, Saleem S.; Hofman, Gerard L.; Kee, Robert J.; King, Jeffrey C.

2014-10-01

33

BWXT commercialization activities for GTRI LEU U-Mo fuels  

International Nuclear Information System (INIS)

BWX Technologies (BWXT), the United States' research reactor fuel supplier for plate type fuel, has been contracted to provide commercialization support activities under the Global Threat Reduction Initiative (GTRI) program to develop and qualify low enrichment uranium (LEU), high density fuels suitable for most of the world's research reactors by the end of 2010. The program's main effort has been testing of uranium-molybdenum alloy fuels (U-Mo), and in light of recent fuel failures with dispersion type fuels, emphasis has now been placed on developing modified and alternative fuels. BWXT's contract scope entails identifying requirements and planning the transition to the new LEU fuels. As there is no clearly preferred fuel technology at this point, multiple commercialization paths must be evaluated. Our baseline approach assumes the fuel is monolithic U-10Mo, and the fuel meat and aluminum alloy plate are hot isostatic pressed (HIP) together. Preliminary results are supportive of this method, however, there is potential for significant interaction between the fuel meat and aluminum alloy plate during the HIP process. Alternative bonding methods, e.g. friction stir welding are being evaluated, as well as modifying the baseline HIP parameters. Additionally, modified dispersed fuel systems are considered. Aspects of each fuel technology and their manufacturing impact are presented and discussed. (author)

34

Morning light cleanup and recovery operation: simulation studies of possible reactor fuels  

International Nuclear Information System (INIS)

The nuclear fuel for Cosmos 954, the orbiting Russian reactor that broke up on reentry during January of 1978, has been identified as a U--Mo alloy containing about 10 wt% molybdenum. Identification was based on a combination of simulation studies at LLL, examination of fuel debris at Whiteshell Nuclear Research Establishment (WNRE), Pinawa, Manitoba, and reactor technology knowledge. In the LLL simulation studies, mixtures of uranium, molybdenum, and UO2 were heated under conditions that simulated reentry and then examined by scanning electron microscopy, energy dispersive spectrometry, and x-ray diffraction. These studies indicated metallic behavior and suggested a U--Mo alloy. The identification was useful in assisting the Canadians in recovery, cleanup, and health/safety activities associated with the radioactive debris, which was scattered over a wide region of the Great Slave Lake

35

Selenium fuel: Surface engineering of U(Mo) particles to optimise fuel performance  

International Nuclear Information System (INIS)

Recent developments on the stabilisation of U(Mo) in-pile behaviour in plate-type fuel have focussed almost exclusively on the addition of Si to the Al matrix of the fuel. This has now culminated in a qualification effort in the form of the European LEONIDAS initiative for which irradiations will start in 2010. In this framework, many discussions have been held on the Si content of the matrix needed for stabilisation of the interaction phase and the requirement for the formation of Si-rich layers around the particles during the fabrication steps. However, it is clear that the Si needs to be incorporated in the interaction phase for it to be effective, for which the currently proposed methods depend on a diffusion mechanism, which is difficult to control. This has lead to the concept of a Si coated particle as a more efficient way of incorporating the Si in the fuel by putting it immediately where it will be required : at the fuel-matrix interface. As part of the SELENIUM (Surface Engineered Low ENrIched Uranium-Molybdenum fuel) project, SCK CEN has built a sputter coater for PVD magnetron sputter coating of particles in collaboration with the University of Ghent. The coater is equipped with three 3 inch magnetron sputter heads, allowing deposition of 3 different elements or a single element at high deposition speed. The particles are slowly rotated in a drum to produce homogeneous layer thicknesses. (author)

36

Assumptions and Criteria for Performing a Feasability Study of the Conversion of the High Flux Isotope Reactor Core to Use Low-Enriched Uranium Fuel  

Energy Technology Data Exchange (ETDEWEB)

A computational study will be initiated during fiscal year 2006 to examine the feasibility of converting the High Flux Isotope Reactor from highly enriched uranium fuel to low-enriched uranium. The study will be limited to steady-state, nominal operation, reactor physics and thermal-hydraulic analyses of a uranium-molybdenum alloy that would be substituted for the current fuel powder--U{sub 3}O{sub 8} mixed with aluminum. The purposes of this document are to (1) define the scope of studies to be conducted, (2) define the methodologies to be used to conduct the studies, (3) define the assumptions that serve as input to the methodologies, (4) provide an efficient means for communication with the Department of Energy and American research reactor operators, and (5) expedite review and commentary by those parties.

Primm, R.T., III; Ellis, R.J.; Gehin, J.C.; Moses, D.L.; Binder, J.L.; Xoubi, N. (U. of Cincinnati)

2006-02-01

37

Low-Enriched Uranium Fuel Conversion Activities for the High Flux Isotope Reactor, Annual Report for FY 2011  

Energy Technology Data Exchange (ETDEWEB)

This report describes progress made during FY11 in ORNL activities to support converting the High Flux Isotope Reactor (HFIR) from high-enriched uranium (HEU) fuel to low-enriched uranium (LEU) fuel. Conversion from HEU to LEU will require a change in fuel form from uranium oxide to a uranium-molybdenum (UMo) alloy. With both radial and axial contouring of the fuel foil and an increase in reactor power to 100 MW, calculations indicate that the HFIR can be operated with LEU fuel with no degradation in performance to users from the current levels achieved with HEU fuel. Studies are continuing to demonstrate that the fuel thermal safety margins can be preserved following conversion. Studies are also continuing to update other aspects of the reactor steady state operation and accident response for the effects of fuel conversion. Technical input has been provided to Oregon State University in support of their hydraulic testing program. The HFIR conversion schedule was revised and provided to the GTRI program. In addition to HFIR conversion activities, technical support was provided directly to the Fuel Fabrication Capability program manager.

Renfro, David G [ORNL; Cook, David Howard [ORNL; Freels, James D [ORNL; Griffin, Frederick P [ORNL; Ilas, Germina [ORNL; Sease, John D [ORNL; Chandler, David [ORNL

2012-03-01

38

Uranium-Molybdenum particles produced by electro-erosion  

International Nuclear Information System (INIS)

We have produced spheroidal U-Mo particles by the electro-erosion method using pure water as dielectric. The particles were characterised by optical metallography, scanning electron microscopy, energy dispersive spectrometry (EDS-EDAX) and X-ray diffraction. Spheroidal UO2 particles with a peculiar distribution size were obtained with two distribution centred at 10 and 70 ?m. The obtained particles have central inclusions of U and Mo compounds. (author)

39

Material test reactor fuel research at the BR2 reactor  

International Nuclear Information System (INIS)

The construction of new, high performance material test reactor or the conversion of such reactors' core from high enriched uranium (HEU) to low enriched uranium (LEU) based fuel requires several fuel qualification steps. For the conversion of high performance reactors, high density dispersion or monolithic fuel types are being developed. The Uranium-Molybdenum fuel system has been selected as reference system for the qualification of LEU fuels. For reactors with lower performance characteristics, or as medium enriched fuel for high performance reactors, uranium silicide dispersion fuel is applied. However, on the longer term, the U-Mo based fuel types may offer a more efficient fuel alternative and-or an easier back-end solution with respect to the silicide based fuels. At the BR2 reactor of the Belgian nuclear research center, SCK-CEN in Mol, several types of fuel testing opportunities are present to contribute to such qualification process. A generic validation test for a selected fuel system is the irradiation of flat plates with representative dimensions for a fuel element. By flexible positioning and core loading, bounding irradiation conditions for fuel elements can be performed in a standard device in the BR2. For fuel element designs with curved plates, the element fabrication method compatibility of the fuel type can be addressed by incorporating a set of prototype fuel plates in a mixed driver fuel element of the BR2 reactor. These generic types of tests ar2 reactor. These generic types of tests are performed directly in the primary coolant flow conditions of the BR2 reactor. The experiment control and interpretation is supported by detailed neutronic and thermal-hydraulic modeling of the experiments. Finally, the BR2 reactor offers the flexibility for irradiation of full size prototype fuel elements, as 200mm diameter irradiation channels are available. These channels allow the accommodation of various types of prototype fuel elements, eventually using a dedicated cooling loop to provide the required thermal and hydraulic conditions. The availability of a comprehensive set of post irradiation examination facilities on site complements the versatile BR2 reactor to provide a set of high performance tools for MTR fuel qualification. (author)

40

Conceptual Design Parameters for HFIR LEU U-Mo Fuel Conversion Experimental Irradiations  

Energy Technology Data Exchange (ETDEWEB)

The High Flux Isotope Reactor (HFIR) is a versatile research reactor that is operated at the Oak Ridge National Laboratory (ORNL). The HFIR core is loaded with high-enriched uranium (HEU) and operates at a power level of 85 MW. The primary scientific missions of the HFIR include cold and thermal neutron scattering, materials irradiation, and isotope production. An engineering design study of the conversion of the HFIR from HEU to low-enriched uranium (LEU) fuel is ongoing at the Oak Ridge National Laboratory. The LEU fuel considered is based on a uranium-molybdenum alloy that is 10 percent by weight molybdenum (U-10Mo) with a 235U enrichment of 19.75 wt %. The LEU core design discussed in this report is based on the design documented in ORNL/TM-2010/318. Much of the data reported in Sections 1 and 2 of this document was derived from or taken directly out of ORNL/TM-2010/318. The purpose of this report is to document the design parameters for and the anticipated normal operating conditions of the conceptual HFIR LEU fuel to aid in developing requirements for HFIR irradiation experiments.

Renfro, David G [ORNL; Cook, David Howard [ORNL; Chandler, David [ORNL; Ilas, Germina [ORNL; Jain, Prashant K [ORNL

2013-03-01

 
 
 
 
41

A physical description of fission product behavior fuels for advanced power reactors.  

Energy Technology Data Exchange (ETDEWEB)

The Global Nuclear Energy Partnership (GNEP) is considering a list of reactors and nuclear fuels as part of its chartered initiative. Because many of the candidate materials have not been explored experimentally under the conditions of interest, and in order to economize on program costs, analytical support in the form of combined first principle and mechanistic modeling is highly desirable. The present work is a compilation of mechanistic models developed in order to describe the fission product behavior of irradiated nuclear fuel. The mechanistic nature of the model development allows for the possibility of describing a range of nuclear fuels under varying operating conditions. Key sources include the FASTGRASS code with an application to UO{sub 2} power reactor fuel and the Dispersion Analysis Research Tool (DART ) with an application to uranium-silicide and uranium-molybdenum research reactor fuel. Described behavior mechanisms are divided into subdivisions treating fundamental materials processes under normal operation as well as the effect of transient heating conditions on these processes. Model topics discussed include intra- and intergranular gas-atom and bubble diffusion, bubble nucleation and growth, gas-atom re-solution, fuel swelling and ?scion gas release. In addition, the effect of an evolving microstructure on these processes (e.g., irradiation-induced recrystallization) is considered. The uranium-alloy fuel, U-xPu-Zr, is investigated and behavior mechanisms are proposed for swelling in the {alpha}-, intermediate- and {gamma}-uranium zones of this fuel. The work reviews the FASTGRASS kinetic/mechanistic description of volatile ?scion products and, separately, the basis for the DART calculation of bubble behavior in amorphous fuels. Development areas and applications for physical nuclear fuel models are identified.

Kaganas, G.; Rest, J.; Nuclear Engineering Division; Florida International Univ.

2007-10-18

42

Swelling of U(Mo) dispersion fuel under irradiation – Non-destructive analyses of the SELENIUM plates  

International Nuclear Information System (INIS)

Extensive fuel-matrix interactions leading to plate pillowing have caused a severe impediment on the development of a suitable high density low-enriched uranium dispersion fuel for high power applications in research reactors. Surface engineering of the U(Mo) kernel surfaces, where the interaction occurs, is put forward by SCK?CEN as a possible solution in the Surface Engineering of Low ENrIched Uranium Molybdenum fuel (SELENIUM) program. The project involved the construction of a sputter coater, the coating of U(Mo) kernels, the production of fuel plates, the irradiation and post-irradiation examination of 2 plates. The irradiation of 2 distinct (600 nm Si and 1000 nm ZrN coated) full size, flat fuel plates was performed in the BR2 reactor in 2012. The irradiation conditions were: 470 W/cm2 peak Beginning Of Life (BOL) power, with a ?70% 235U peak burnup. The plates were successfully irradiated and did not show any pillowing at the end of the irradiation. This paper reports the results and interpretation of the non-destructive post-irradiation examinations that were performed on these fuel plates and derives a law for the fuel swelling evolution with burnup for this fuel type. It further reports additional PIE results obtained on fuel plates irradiated in campaigns in the past in order to allow a complete comparison with all results obtained under similar conditions. The fuel swelling is shown to evolve linearly with the fission density, with an increase in swelling rate around 2.5 × 1021 f/cm3, which is associated with the restructuring of the fuel. A further increase in swelling rate is observed at the highest burnups, which is discussed in this article

43

Advanced research reactor fuel development  

Energy Technology Data Exchange (ETDEWEB)

The fabrication technology of the U{sub 3}Si fuel dispersed in aluminum for the localization of HANARO driver fuel has been launches. The increase of production yield of LEU metal, the establishment of measurement method of homogeneity, and electron beam welding process were performed. Irradiation test under normal operation condition, had been carried out and any clues of the fuel assembly breakdown was not detected. The 2nd test fuel assembly has been irradiated at HANARO reactor since 17th June 1999. The quality assurance system has been re-established and the eddy current test technique has been developed. The irradiation test for U{sub 3}Si{sub 2} dispersed fuels at HANARO reactor has been carried out in order to compare the in-pile performance of between the two types of U{sub 3}Si{sub 2} fuels, prepared by both the atomization and comminution processes. KAERI has also conducted all safety-related works such as the design and the fabrication of irradiation rig, the analysis of irradiation behavior, thermal hydraulic characteristics, stress analysis for irradiation rig, and thermal analysis fuel plate, for the mini-plate prepared by international research cooperation being irradiated safely at HANARO. Pressure drop test, vibration test and endurance test were performed. The characterization on powders of U-(5.4 {approx} 10 wt%) Mo alloy depending on Mo content prepared by rotating disk centrifugal atomization process was carried out in order to investigate the phase stability of the atomized U-Mo alloy system. The {gamma}-U phase stability and the thermal compatibility of atomized U-16at.%Mo and U-14at.%Mo-2at.%X(: Ru, Os) dispersion fuel meats at an elevated temperature have been investigated. The volume increases of U-Mo compatibility specimens were almost the same as or smaller than those of U{sub 3}Si{sub 2}. However the atomized alloy fuel exhibited a better irradiation performance than the comminuted alloy. The RERTR-3 irradiation test of nano-plates will be conducted in the Advanced Test Reactor(ATR). 49 compacts with a uranium density of 8 gU/cc consist of 7 different atomized uranium-molybdenum alloy powders. The tensile strength increased and the elongation decreased with increasing the volume fraction of U-10Mo powders in dispersion fuel. The tensile strength was lower and elongation was larger in dispersion fuel using atomized U-10Mo powders than that using comminuted fuel powders. The green strength of the comminuted powder compacts was about twice as large as that of the atomized powder compacts. It is suggested that the compacting condition required to fabricate the atomized powder compacts is over the 350MPa. The comminuted irregular shaped particles and smaller particle size of fuel powders showed improved homogeneity of powder mixture. The homogeneity of powder mixtures increased to a minimum at approximately 0.10 wt% moisture and then decreased with moisture content.

Kim, Chang Kyu; Pak, H. D.; Kim, K. H. [and others

2000-05-01

44

Advanced research reactor fuel development  

International Nuclear Information System (INIS)

The fabrication technology of the U3Si fuel dispersed in aluminum for the localization of HANARO driver fuel has been launches. The increase of production yield of LEU metal, the establishment of measurement method of homogeneity, and electron beam welding process were performed. Irradiation test under normal operation condition, had been carried out and any clues of the fuel assembly breakdown was not detected. The 2nd test fuel assembly has been irradiated at HANARO reactor since 17th June 1999. The quality assurance system has been re-established and the eddy current test technique has been developed. The irradiation test for U3Si2 dispersed fuels at HANARO reactor has been carried out in order to compare the in-pile performance of between the two types of U3Si2 fuels, prepared by both the atomization and comminution processes. KAERI has also conducted all safety-related works such as the design and the fabrication of irradiation rig, the analysis of irradiation behavior, thermal hydraulic characteristics, stress analysis for irradiation rig, and thermal analysis fuel plate, for the mini-plate prepared by international research cooperation being irradiated safely at HANARO. Pressure drop test, vibration test and endurance test were performed. The characterization on powders of U-(5.4 ? 10 wt%) Mo alloy depending on Mo content prepared by rotating disk centrifugal atomization process was carried out in order to investigate the phase stability of the atomized U-Mo alloy system. The ?-U phase stability and the thermal compatibility of atomized U-16at.%Mo and U-14at.%Mo-2at.%X(: Ru, Os) dispersion fuel meats at an elevated temperature have been investigated. The volume increases of U-Mo compatibility specimens were almost the same as or smaller than those of U3Si2. However the atomized alloy fuel exhibited a better irradiation performance than the comminuted alloy. The RERTR-3 irradiation test of nano-plates will be conducted in the Advanced Test Reactor(ATR). 49 compacts with a uranium density of 8 gU/cc consist of 7 different atomized uranium-molybdenum alloy powders. The tensile strength increased and the elongation decreased with increasing the volume fraction of U-10Mo powders in dispersion fuel. The tensile strength was lower and elongation was larger in dispersion fuel using atomized U-10Mo powders than that using comminuted fuel powders. The green strength of the comminuted powder compacts was about twice as large as that of the atomized powder compacts. It is suggested that the compacting condition required to fabricate the atomized powder compacts is over the 350MPa. The comminuted irregular shaped particles and smaller particle size of fuel powders showed improved homogeneity of powder mixture. The homogeneity of powder mixtures increased to a minimum at approximately 0.10 wt% moisture and then decreased with moisture content

45

The reprocessing of irradiated fuels improvement and extension of the solvent extraction process; Le traitement des combustibles irradies amelioration et extension du procede utilisant les solvants  

Energy Technology Data Exchange (ETDEWEB)

Improvements made in the conventional tri-butylphosphate process are described, in particular. the concentration and the purification of plutonium by one extraction cycle using tri-butyl-phosphate with reflux; and the use of an apparatus working continuously for precipitating plutonium oxalate, for calcining the oxalate, and for fluorinating the oxide. The modifications proposed for the treatment of irradiated uranium - molybdenum alloys are described, in particular, the dissolution of the fuel, and the concentration of the fission product solutions. The solvent extraction treatment is used also for the plutonium fuels utilized for the fast breeder reactor (Rapsodie) An outline of the process is presented and discussed, as well as the first experimental results and the plans for a pilot plant having a capacity of 1 kg/day. The possible use of tn-lauryl-amine in the plutonium purification cycle is now under consideration for the processing plant at La Hague. The flowsheet for this process and its performance are presented. The possibility of vitrification is considered for the final treatment of the concentrated radioactive wastes from the Marcoule (irradiated uranium) and La Hague (irradiated uranium-molybdenum) Centers. Three possible processes are described and discussed, as well as the results obtained from the operation of the corresponding experimental units using tracers. (authors) [French] On decrit les ameliorations apportees au procede classique utilisant le phosphate tributylique, et notamment la concentration et la purification du plutonium par un cycle d'extraction au tributylphosphate avec reflux, l'utilisation d'un appareillage continu de precipitation d'oxalate de plutonium, de calcination de l'oxalate, et de fluoration de l'oxyde. On presente les modifications envisagees pour le traitement des alliages uranium-molybdene irradies, principalement en ce qui concerne la dissolution du combustible et la concentration des solutions de produits de fission. Le traitement au solvant est egalement utilise pour les combustibles de la pile convertisseuse du plutonium (Rapsodie). On expose et commente le schema du traitement, les premiers resultats experimentaux et le projet d'une installation pilote de 1 kg/jour. L'utilisation de la tn-laurylamine dans le cycle de purification du plutonium est envisagee dans l'usine de traitement de La Hague. On presente le schema adopte et les performances du procede. On envisage la vitrification comme traitement definitif des dechets radioactifs concentres des Centres de Marcoule (uranium-irradie) et La Hague (uranium-molybdene irradie). Trois procedes possibles sont decrits et commentes, ainsi que les resultats d'exploitation des installations correspondantes sur elements traceurs. (auteurs)

Faugeras, P.; Chesne, A. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1964-07-01

46

Nuclear Safety Considerations in Fabrication of Massive, Partially-Enriched Uranium-Molybdenum Reactor Parts  

International Nuclear Information System (INIS)

Massive metallic components of partially-enriched uranium-235 mixed with 10 wt.% molybdenum have been successfully fabricated at the USAEC Oak Ridge Y-12 Plant for Super Kukla, a prompt burst reactor. Nuclear safety analyses were performed and procedures developed to permit fabrication of the reactor components in the largest single pieces possible within the limitations imposed by criticality and manufacturing capabilities. Metal parts of finished weights up to 268 kg each were cast, machined, inspected and shipped. Nuclear safety problems encountered in the production of approximately 5 tons of these reactor components included considerations of reflected and unreflected massive pieces of uranium metal and alloy, accumulations of machine turnings in various conditions of moderation by hydrogenous liquids and uraniumbearing solutions from plating processes. Although some operational steps were resolved by application of criticality data and established practices for uranium more highly enriched in 235U (? 90%), it was necessary to establish critical parameters for the intermediate 20% enrichment desired and to evaluate the effects of dilution by molybdenum. Calculations to obtain the criticality numbers were made using the Sn reactor transport theory approximation IBM-7090 machine codes DTK and DDK. Hansen-Roach 16 energy group cross-sections were used with appropriate resonance region corrections. Checks against Los Alamos critical experimental data foros Alamos critical experimental data for 28.9, 38.0 and 50.5 % enriched uranium were made to assist in establishing the reliability of the calculations. Each proposed operational step was analysed using the 'double contingency' criterion. On the basis of the analyses, it was possible to devise procedures and equipment to safely allow casting charges of up to 300 kg of uranium metal (60 kg 235U) or 400 kg of alloy (72 kg 235U) in cylindrical crucibles. Especial care was required to prevent inadvertent mixing with either highly enriched uranium or depleted uranium from adjacent working areas. Most of the reactor parts themselves were readily identifiable due to their large size and unique configuration; however, machine turnings, chips and solutions were not sufficiently distinctive for visual identification as 20% enrichment. These materials were accordingly treated as highly enriched (?90%) until proven otherwise by analyses. (author)

47

Characterization of cubic ?-phase uranium molybdenum alloys synthesized by ultrafast cooling  

International Nuclear Information System (INIS)

Highlights: ? U-Mo alloys prepared by splat cooling. ? A small amount of ?-phase was preserved in pure splat-cooled uranium specimen. ? Crystal structure characterized by X-ray diffraction and EBSD. ? A stability of ?-phase for alloys with 11–15 at.% Mo. ? Superconducting transition, Tc = 1.24 K (pure-U) to 2.11 K (U-15 at.% Mo). - Abstract: U-Mo alloys with Mo concentration in the range of 0–15 at.% Mo were prepared using a splat-cooling technique. Phase analysis using X-ray diffraction (XRD), scanning electron microscopy (SEM) and electron back-scatter diffraction (EBSD) revealed the presence of a small amount of ?-U phase retained at room temperature alongside the majority ?-U phase and opening the possibility of stabilizing the ?-phase at room temperature in uranium metal by ultrafast cooling. The double-phase (? + ?) structure with predominance of the ?-phase was obtained in the alloys with 0–10 at.% Mo. Increasing further Mo doping leads to the ?° phase (for 11–12 at.% Mo) and pure cubic ? phase (for 15 at.% Mo). The superconducting transition was investigated by low-temperature resistivity measurements down to 0.3 K in magnetic fields up to 5 T. All the splats become superconducting with Tc in the range from 1.24 K (pure U splat) to 2.11 K (U-15 at.% Mo). The superconductivity in the ?-phase alloys exhibited a much higher upper critical field than for ?-phase material. Electrical resistivity of the ?-alloys ?-alloys (?11 at.% Mo) exhibited a negative temperature coefficient from room temperature down to the superconducting transition.

48

Study of transformations by annealing of the body. Centred cubic ? phase of uranium-molybdenum alloys  

International Nuclear Information System (INIS)

By annealing at different temperatures, we have studied the transformations of the body centred cubic ? phase for two alloys containing 6 and 10 per cent molybdenum by weight respectively. There is a return to the equilibrium state by formation of the stable ? orthorhombic and ? ordered tetragonal phases, following two types of reaction: - pearlite transformation by nucleation and growth from the grain boundaries, preponderant when the annealing takes place at temperature above 400 deg. C, and identical for the two types of alloys. This reaction has already been studied by numerous authors, who have constructed the corresponding TTT curves, - transformation inside the grains of the quenched solid solution when annealing takes place at 400 deg. C or below: 6 per cent alloy - precipitation of fine a phase particles, followed by progressive ordering of the solid solution enriched in molybdenum, 10 per cent alloy - formation of small ordered regions and then a fine a phase precipitate. In the course of this work we have paid particular attention to the study of intragranular reactions after low-temperature annealing, the reactions involved in this case not having been explained up to the present. The ? phase transformation has been studied by means of three techniques: micrography - microhardness tests - X-ray diffraction. (author)

49

Thermal cycling behaviour and thermal stability of uranium-molybdenum alloys of low molybdenum content  

International Nuclear Information System (INIS)

We have studied the behaviour during thermal cycling of as-cast U-Mo alloys whose molybdenum content varies from 0.5 to 3 per cent; results are given concerning grain stability during extended heat treatments and the effect of treatments combining protracted heating with thermal cycling. The thermal cycling treatments were carried out at 550, 575, 600 and 625 deg C for 1000 cycles; the protracted heating experiments were done at 550, 575, 600 and 625 deg C for 2000 hours (4000 hrs at 625 deg C). The 0.5 per cent alloy resists much better to the thermal cycling than does the non-alloyed uranium. This resistance is, however, much lower than that of alloys containing over l per cent, even at 550 deg C it improves after a heat treatment for grain-refining. Alloys of over 1.1 per cent have a very good resistance to a cycling treatment even at 625 deg C, and this behaviour improves with increasing concentrations up to 3 per cent. An increase in the temperature up to the ?-phase has few disadvantages provided that it is followed by rapid cooling (50 to 100 deg C/min). The ? grain is fine, the ?-phase is of the modular form, and the behaviour during a thermal cycling treatment is satisfactory. If this cooling is slow (15 deg /hr) the ?-grain is coarse and cycling treatment behaviour is identical to that of the 0.5 per cent alloy. The protracted heat treatments showed that the ?-grain exhibits satisfactory stability after 2000 hours at 575, 600 and 625 deg C, and after 4000 hours at 625 deg C. A heat cycling treatment carried out after these tests affects only very little the behaviour of these alloys during cycling. (authors)

50

Design Study for a Low-Enriched Uranium Core for the High Flux Isotope Reactor, Annual report for FY 2009  

Energy Technology Data Exchange (ETDEWEB)

This report documents progress made during FY 2009 in studies of converting the High Flux Isotope Reactor (HFIR) from high enriched uranium (HEU) fuel to low enriched uranium (LEU) fuel. Conversion from HEU to LEU will require a change in fuel form from uranium oxide to a uranium-molybdenum alloy. With axial and radial grading of the fuel foil and an increase in reactor power to 100 MW, calculations indicate that the HFIR can be operated with LEU fuel with no degradation in reactor performance from the current level. Results of selected benchmark studies imply that calculations of LEU performance are accurate. Studies are reported of the application of a silicon coating to surrogates for spheres of uranium-molybdenum alloy. A discussion of difficulties with preparing a fuel specification for the uranium-molybdenum alloy is provided. A description of the progress in developing a finite element thermal hydraulics model of the LEU core is provided.

Chandler, David [ORNL; Freels, James D [ORNL; Ilas, Germina [ORNL; Miller, James Henry [ORNL; Primm, Trent [ORNL; Sease, John D [ORNL; Guida, Tracey [University of Pittsburgh; Jolly, Brian C [ORNL

2010-02-01

51

Fueling systems  

International Nuclear Information System (INIS)

This report deals with concepts of the Tiber II tokamak reactor fueling systems. Contained in this report are the fuel injection requirement data, startup fueling requirements, intermediate range fueling requirements, power range fueling requirements and research and development considerations

52

Fuel assumbly  

International Nuclear Information System (INIS)

An integral nuclear fuel element assembly is described which utilises longitudinally finned fuel pins. The continuous or interrupted fins of the fuel pins are brazed to fins of juxtaposed fuel pins or directly to the juxtaposed fuel pins or both. The integrally brazed fuel assembly is designed to satisfy the thermal and hydraulic requirements of a fuel assembly lattice having moderator to fuel atom radios required to achieved high conversion and breeding ratios. (Auth.)

53

Fuel assembly  

International Nuclear Information System (INIS)

To enhance degree of burn-up of fuel in a nuclear reactor, the fuel pins are interconnected in groups by manifolds and the fuel wrapper is provided with an access point or points to allow fission gases in each fuel pin group to be vented periodically by for example laser piercing of one pin of each group or of the manifold. (author)

54

Fuel assembly  

International Nuclear Information System (INIS)

Purpose: To prevent the bending of a fuel rod caused by the difference in the elongation between a joined fuel rod and a standard fuel rod thereby maintain the fuel rod integrity. Constitution: A joined fuel rod is in a thread engagement at its lower end plug thereof with a lower plate, while passed through at its upper end plug into an upper tie plate and secured with a nut. Further, a standard fuel rod is engaged at its upper end plug and lower end plug with the upper tie plate and the lower tie plate respectively. Expansion springs are mounted to the upper end plugs of these bonded fuel rods and the standard fuel rods for preventing this lifting. Each of the fuel rods comprises a plurality of sintered pellets of nuclear fuel materials laminated in a zircaloy fuel can. The content of the alloy ingredient in the fuel can of the bonded fuel rod is made greater than that of the alloy ingredient of the standard fuel rod. this can increase the elongation for the bonded fuel rod, and the spring of the standard fuel rod is tightly bonded to prevent the bending. (Yoshino, Y.)

55

Fuel assemblies  

International Nuclear Information System (INIS)

Purpose: To increase the control amount for the excess reactivity for fuel rods containing burnable poisons. Constitution: The fuel assembly comprises group A fuel rods each composed of an upper tie plate, a lower tie plate and a fuel rod retained at the upper end thereof to the upper tie plate and the lower tie plate. The outer diameter for the group A fuel is set, for example, to 12.3 mm, while the outer diameter for group B fuel rod is set, for example, to 13.5 mm. The group A fuel rod is filled in the inside with fuel pellets containing uranium-235 but not containing gadolinia as burnable material. While on the other hand, the group B fuel rod is filled with fuel pellets containing uranium 235 and gadolinia. If the outer diameter of the group B fuel rod is about 1.1 times of the outer diameter for the group A fuel rod, the number of the group B fuel rods can be reduced by one as compared with the usual case, the gadolinia weight ratio can be reduced and the pressure for the group B fuel rod can also be decreased. This can improve the integrity of the gadolinia-containing fuel rod. (Seki, T.)

56

Fuel assembly  

International Nuclear Information System (INIS)

The fuel assembly of the present invention comprises a fuel rod filled with pellets made of a mixed oxide of uranium and plutonium, and a fuel rod filled with pellets in which transuranium elements selected from neptinium, amerisium and curium are further enriched to the pellet described above. In a fuel rod containing more transuranium elements of lower heat conductivity compared with uranium, linear power density can be relatively reduced. Accordingly, the temperature at the center of the fuel can be lowered compared with existent fuel assemblies in which transuranium elements are unformly enriched. (T.M.)

57

Fuel gases  

International Nuclear Information System (INIS)

This paper gives a brief presentation of the context, perspectives of production, specificities, and the conditions required for the development of NGV (Natural Gas for Vehicle) and LPG-f (Liquefied Petroleum Gas fuel) alternative fuels. After an historical presentation of 80 years of LPG evolution in vehicle fuels, a first part describes the economical and environmental advantages of gaseous alternative fuels (cleaner combustion, longer engines life, reduced noise pollution, greater natural gas reserves, lower political-economical petroleum dependence..). The second part gives a comparative cost and environmental evaluation between the available alternative fuels: bio-fuels, electric power and fuel gases, taking into account the processes and constraints involved in the production of these fuels. (J.S.)

58

Fuel assembly  

International Nuclear Information System (INIS)

Purpose: To minimize the changes in the temperature distribution due to deviation of fuel pins in fuel assemblies of an lmfbr type reactor. Constitution: A fuel assembly is supported on a plurality of support plates provided at the lower inside of a wrapper tube. Fasteners at the lower end plug of cladding tubes for closing the lower end thereof are assembled in such way that the directions of the fasteners are opposed to each other between each of adjacent fuel pins, in particular, those fuel pins supported on different support plates. With the above constituion, if the fuel pins tend to move laterally in the same direction acted by fluid pressure due to coolant flow, deviation of the fuel pins is not resulted to all of the pins since at least one of the adjacent fuel pins is fixed to the support plate by the fastener to be hindered from displacement. (Kawakami, Y.)

59

Alcohol fuels  

Directory of Open Access Journals (Sweden)

Full Text Available The existing motor fuel alternative, namely alcohol - biomethanol, bioethanol and biobutanol, the possibility of using them in different concentrations of gasoline were consider. From the most perspective of considered alternative fuels for were shows.

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2010-02-01

60

Fuel element  

International Nuclear Information System (INIS)

Purpose: To eliminate occurrence of stress corrosion crack at a fuel can by restricting the discharge amount of a corrosive fission product stored in a fuel pellet. Constitution: Small amounts of metal oxides such as calcium oxide, cobalt oxide, copper oxide, nickel oxide, chromium oxide and iron oxide having two or three valence are added to a fuel element of uranium dioxide sealed in a zirconium alloy fuel can. (Aizawa, K.)

 
 
 
 
61

Fuel assembly  

International Nuclear Information System (INIS)

Purpose: To effectively utilize gadolinia reactivity without deteriorating the thermodynamic properties of fuel in a BWR type reactor fuel element containing gadolinia as burnable poison. Constitution: One or both of isotopes Gd-155 and Gd-157 having large reactivity in gadolinia is concentrated, and a fuel element is fabricated with the concentrated isotope. (Kamimura, M.)

62

Fueling method  

International Nuclear Information System (INIS)

Purpose: To enable calculation for the reactor power from each of fuels upon successive replace of fresh fuels with long fuel effective length, without changing the reactor performance calculating device. Method: In a operation transfer cycle of replacing fuels charged in the reactor core, for example, each by 1/3 on every operation cycle of the reactor core, 1/3 of the fuels with the effective fuel length A is replaced with fresh fuels with the effective fuel length B. In this case, the fresh fuels constitute such an arrangement that a layer of natural uranium or depleted uranium is added to the upper portion of the reactor core containing the fuels with the effective fuel length A. The neutron reactivity of the natural uranium or depleted uranium is very much low and the reactor power from this portion is negligibly small. Accordingly, the reactor core performance calculation for the reactor core can be made as that for the reactor core with the effective fuel length A. (Seki, T.)

63

Nuclear fuels  

Energy Technology Data Exchange (ETDEWEB)

Fuel is one of the essential components in a reactor. It is within that fuel that nuclear reactions take place, i.e. fission of heavy atoms, uranium and plutonium. Fuel is at the core of the reactor, but equally at the core of the nuclear system as a whole. Fuel design and properties influence reactor behavior, performance, and safety. Even though it only accounts for a small part of the cost per kilowatt-hour of power provided by current nuclear power plants, good utilization of fuel is a major economic issue. Major advances have yet to be achieved, to ensure longer in-reactor dwell-time, thus enabling fuel to yield more energy; and improve ruggedness. Aside from economics, and safety, such strategic issues as use of plutonium, conservation of resources, and nuclear waste management have to be addressed, and true technological challenges arise. This Monograph surveys current knowledge regarding in-reactor behavior, operating limits, and avenues for R and D. It also provides illustrations of ongoing research work, setting out a few noteworthy results recently achieved. Content: 1 - Introduction; 2 - Water reactor fuel: What are the features of water reactor fuel? 9 (What is the purpose of a nuclear fuel?, Ceramic fuel, Fuel rods, PWR fuel assemblies, BWR fuel assemblies); Fabrication of water reactor fuels (Fabrication of UO{sub 2} pellets, Fabrication of MOX (mixed uranium-plutonium oxide) pellets, Fabrication of claddings); In-reactor behavior of UO{sub 2} and MOX fuels (Irradiation conditions during nominal operation, Heat generation, and removal, The processes involved at the start of irradiation, Fission gas behavior, Microstructural changes); Water reactor fuel behavior in loss of tightness conditions (Cladding, the first containment barrier, Causes of failure, Consequences of a failure); Microscopic morphology of fuel ceramic and its evolution under irradiation; Migration and localization of fission products in UOX and MOX matrices (The ceramic under irradiation, Bubbles and precipitates, Modeling fuel behavior); Modeling defects and fission products in UO{sub 2} ceramic by ab initio computation (Ab initio computation, Point defects in uranium dioxide, Fission products in uranium dioxide, The indispensable coupling of modeling and experiment); Cladding and assembly materials (What is the purpose of cladding?, Zirconium alloys, Claddings: required to exhibit good mechanical strength, Mechanical behavior of irradiated Zr alloys, Claddings: required to prove corrosion resistant); Pellet-cladding interaction (The phenomena involved in pellet-cladding interaction (PCI), Experimental simulation of PCI and the lessons to be drawn from it, The requirement for an experimental basis, Numerical simulation of PCI, Towards a lifting of PCI-related operating constraints); Advanced UO{sub 2} and MOX ceramics (Chromium oxide-doped UO{sub 2} fuel, Novel MOX microstructures); Mechanical behavior of fuel assemblies (Assembly mechanical behavior in normal operating conditions, Assembly mechanical behavior in accident situations, Fuel in a loss of primary coolant accident (LOCA)); Introduction to LOCA-type accident transients (Overview of thermal-hydraulic and fuel-related aspects, Incidence of LOCA transients on the thermal-metallurgical-mechanical behavior of zirconium-base alloy cladding); Fuel in a reactivity insertion accident (RIA) (Safety criteria); Fuel in a severe accident (The VERCORS analytical program, The Phebus-FP global tests, Control of severe accidents in the EPR reactor); In-core fuel management (Relationships between cycle length, maximum burnup, and batch fraction Enrichment and burnable poisons, The impact of the nature of the fuel used, and its evolution, on the major parameters of core physics, and management Prospects for future trends in core management); Fuel cycle material balances (In-core evolution of materials, Decay heat and potential radiotoxicity, Plutonium management); Long-term behavior of spent fuel (The nature of spent nuclear fuel, Anticipated evolution of fuel in dry storage, Anticipated evolutio

Beauvy, M.; Berthoud, G.; Defranceschi, M.; Ducros, G.; Guerin, Y.; Limoge, Y.; Madic, Ch.; Santarini, G.; Seiler, J.M.; Sollogoub, P.; Vernaz, E.; Guillet, J.L.; Ballagny, A.; Bechade, J.L.; Bonin, B.; Brachet, J.Ch.; Delpech, M.; Dubois, S.; Ferry, C.; Freyss, M.; Gilbon, D.; Grouiller, J.P.; Iracane, D.; Lansiart, S.; Lemoine, P.; Lenain, R.; Marsault, Ph.; Michel, B.; Noirot, J.; Parrat, D.; Pelletier, M.; Perrais, Ch.; Phelip, M.; Pillon, S.; Poinssot, Ch.; Vallory, J.; Valot, C.; Pradel, Ph.; Bonin, B.; Bouquin, B.; Dozol, M.; Lecomte, M.; Vallee, A.; Bazile, F.; Parisot, J.F.; Finot, P.; Roberts, J.F

2009-07-01

64

LPG fuel  

International Nuclear Information System (INIS)

LPG fuel has become frequently used through a distribution network with 2 000 service stations over the French territory. LPG fuel ranks number 3 world-wide given that it can be used on individual vehicles, professional fleets, or public transport. What is the environmental benefit of LPG fuel? What is the technology used for these engines? What is the current regulation? Government commitment and dedication on support to promote LPG fuel? Car makers projects? Actions to favour the use of LPG fuel? This article gathers 5 presentations about this topic given at the gas conference

65

Fuel distribution  

Energy Technology Data Exchange (ETDEWEB)

Distribution of fuel is considered from a supply point to the secondary conversion sites and ultimate end users. All distribution is intracity with the maximum distance between the supply point and end-use site generally considered to be 15 mi. The fuels discussed are: coal or coal-like solids, methanol, No. 2 fuel oil, No. 6 fuel oil, high-Btu gas, medium-Btu gas, and low-Btu gas. Although the fuel state, i.e., gas, liquid, etc., can have a major impact on the distribution system, the source of these fuels (e.g., naturally-occurring or coal-derived) does not. Single-source, single-termination point and single-source, multi-termination point systems for liquid, gaseous, and solid fuel distribution are considered. Transport modes and the fuels associated with each mode are: by truck - coal, methanol, No. 2 fuel oil, and No. 6 fuel oil; and by pipeline - coal, methane, No. 2 fuel oil, No. 6 oil, high-Btu gas, medium-Btu gas, and low-Btu gas. Data provided for each distribution system include component makeup and initial costs.

Tison, R.R.; Baker, N.R.; Blazek, C.F.

1979-07-01

66

European Fuel Group's fuel performance  

International Nuclear Information System (INIS)

The European Fuel Group (EFG) comprises three member companies and can provide to European facilities products and services which have been developed by the individual members, or jointly. Several advanced fuel features are now being supplied to European plants and this paper offers a summary of the performance of EFG fuel and the background experience of the individual EFG members. (author)

67

Fuel assembly  

International Nuclear Information System (INIS)

A great number of fuel pins are axially fixed by a plurality stages of grids and surrounded by an outer cylinder, and partition walls partitioning the fuel pins into a plurality of regions are disposed in the outer cylinder. Accordingly, the aparting space between the fuel pins with each other and that between the fuel pins and the outer cylinder are kept apart appropriately. Then, the mutual interference between the outer cylinder and the fuel pins, and that between the partition walls and the fuel pins scarcely occurs even if expansion is caused during reactor operation. Further, since the fuel pins are partitioned to a plurality of regions by the outer cylinder and the partition walls, the flow rate of coolants can be divided for flattening the radial power distribution. If flow rate control means are disposed at the opening end of the outer cylinder, the division can be made further uniform. The whole fuel assemblies are exchanged upon fuel exchange. In this way, the fuel exchange system can be simplified. (T.M.)

68

Fuel elements and fuel services  

International Nuclear Information System (INIS)

Over a development period of twenty years the change was made from 8 x 8 fuel elements to a 10 x 10 configuration offering wider design margins in every respect as a precondition for future power increases, also in BWR plants with high power densities, and entailing advantages in the design of Mox fuel elements (SVEA-96/100 concept). Mean discharge burnups of more than 50 MWd/kg of U can be attained, which results in considerable cost reductions. The lower thermal load per unit area of the heating surface means slower corrosion and some 40% less crud buildup. Fuel element inspections cover the fuel element boxes, measurements of oxide layers, parts of fuel bundles, spacers, and measurements of fuel rod lengths. Fuel element leakages are analyzed by in-core, elevate, telescope, and in-mast sipping techniques, respectively. (orig./HP)

69

Fuel pin  

International Nuclear Information System (INIS)

Purpose: To enable to reduce the reactivity of fuel pins rapidly and surely upon reactivity accident, reduction of coolant flow rate accident, etc. Constitution: Fuel pellets for use as reactor core fuels situated at the upper portion of the a can and fuel pellets for use as axial brackets of a fuel pin are made into an axially hollow structure, and neutron absorbers are disposed to the uppermost portion thereof by way of a low melting metal plate with a melting point, for example, of 700 0C. Accordingly, upon reactivity accident or reduction of coolant flow rate accident, the metal plate is melted causing the neutron absorbers to fall thereby rapidly suppressing the reactivity at the central portion where the power distribution is highest. Accordingly, the temperature rise in the fuel can can be suppressed to prevent melt down accident, etc. (Kawakami, Y.)

70

Fuel assembly  

International Nuclear Information System (INIS)

In a LWR moderation in the inner part of the core is increased by replacing some of the fuel rods in the fuel assembly by tubes containing water. In order to have the possibility of using also tubes with a larger diameter than the fuel rods, it is proposed to provide for W-shaped spacers in the spacer grid instead of the usual V-shaped spacers. The require less space but have got the same elastic force. (UWI)

71

Fuel Cells  

DEFF Research Database (Denmark)

Fuel cells have been the subject of intense research and development efforts for the past decades. Even so, the technology has not had its commercial breakthrough yet. This entry gives an overview of the technological challenges and status of fuel cells and discusses the most promising applications of the different types of fuel cells. Finally, their role in a future energy supply with a large share of fluctuating sustainable power sources, e.g., solar or wind, is surveyed.

Smith, Anders; Pedersen, Allan SchrØder

2014-01-01

72

Nuclear fuel  

International Nuclear Information System (INIS)

All stages of nuclear fuel cycle are analysed with respect to the present situation and future perspectives of supply and demand of services; the prices and the unitary cost estimation of these stages for the international fuel market are also mentioned. From the world resources and projections of uranium consumption, medium-and long term analyses are made of fuel availability for several strategies of use of different reactor types. Finally, the cost of nuclear fuel in the generation of electric energy is calculated to be used in the energetic planning of the electric sector. (M.A.)

73

Fuel spacer  

International Nuclear Information System (INIS)

In a fuel spacer, a chamfer is formed on the outside at the lower end of a ferrule. The distance of the flow channel of coolants in a fuel assembly is different for perpendicular direction and diagonal direction between the fuel rods. At a position of the fuel spacer, an annular flow channel is defined with the surface of the fuel rod and the inner side of the ferrule in the perpendicular direction, and an outer side flow channel of the ferrule in adjacent with the annular flow channel is defined in the diagonal direction. In particular, in the annular flow channel in the diagonal direction, the coolant flow having fast flow rate at the periphery of the surface of the fuel rod is introduced to the outer side flow channel by the chamfer then flows in the form of a compressive flow. Since stream lines at the periphery of the surface of the fuel rod do not approach the surface of the fuel rods and the flow is not compressed, the reduction of the thickness of the liquid membrane flow is moderated. This can suppress the occurrence of transient boiling to improve limit power of the fuel assembly. (N.H.)

74

Fuel cells and hydrogen fuel  

International Nuclear Information System (INIS)

Fuel cells operate in an effective manner today only on hydrogen fuel. The most probable fuels for future use will be hydrogen itself, when it will be available in quantity from renewable sources, natural gas and coal. Both the latter must be converted into hydrogen-rich gases, the first by steam-reforming followed by water-gas shift, the second by steam-oxygen (or air) gasification. Hydrogen fuel cell system for automobiles are examined and their economic feasibility is compared with IC engines. Hydrogen storage problems are also investigated. 9 refs

75

Fuel assembly  

International Nuclear Information System (INIS)

Purpose: To obtain higher unit heat generation amount by radially varying the uranium enrichment degree in the pellets of a fuel rod to thereby render the radial temperature distribution more uniform. Constitution: In a fuel assembly comprising a plurality of fuel rods arranged and disposed by way of spacers in a channel box, with the upper and lower ends of the fuel rods being fixed with upper and lower tie plates, the pellet of the fuel rod is prepared by disposing an uranium layer of lower enrichment degree in the axial center portion and an uranium layer of higher enrichment degree in the axial peripheral, molding and sintering them in a cylindrical configuration. The uranium layer of lower enrichment degree consists of natural uranium (0.711% of uranium 235 content) and the uranium layer of higher enrichment degree has an enrichment degree more than 1.1 times of the average enrichment degree in the pellet. (Aizawa, K.)

76

Fuel assemblies  

International Nuclear Information System (INIS)

Purpose: To provide fuel assemblies having integrity and improved cooling performance, suitable to HCLWR type reactors. Constitution: Taking notice of the fact that the cooling performance of finer diameter fuel rod is more excellent than that of the greater diameter fuel rod, fuel rods of greater and finer diameters are arranged densely under a certain rule. Even if they are arranged densely, the gap between the rod surfaces can be increased as compared with the conventional case and the flow resistance can be decreased to improve the cooling performance. Since the finer diameter fuel rods can increase the density of the fission nuclides by so much as they are excellent in the cooling performance and the density in the greater diameter fuel rods can be lowered to suppress the generation of heat and improve the after-heat removal. That is, although the surface distance between the greater diameter fuel rods is increased and the distance with the finer diameter rods is decreased, the steric angle viewed from the greater diameter rod to the finer diameter rod is decreased as compared with the opposite case and the heat removal property can be improved by so much as the surface distance is reduced. In addition, since the ratio of the surface area to the volume of the heat generation body is greater than that of the greater diameter rods, it is excellent in the cooling performance to greatly improve the heat removal property. (Kamimura, M.)

77

Fuel cells  

...Fuel cells Car manufacturer Lotus has demonstrated a black cab powered by hydrogen fuel cells, which they hope will be just one of ... Generating powerMuch like battery-powered electric cars, those that run on hydrogen use electricity to drive the wheels. But rather than storing that ...taking many hours to recharge, fuel cells generate power onboard by reacting hydrogen and oxygen in the presence of an electrolyte - a non-metallic ... They function as follows: Hydrogen gas is delivered to a negatively charged anode on one side of the cell while oxygen is channeled ...

78

Nuclear fuel  

International Nuclear Information System (INIS)

The nuclear fuel material described has a preset fissile matter level. It contains under 1% plutonium, the balance being uranium possessing a sufficient proportion of U-235 enriched uranium, which, in association with the plutonium, gives the material this fissile matter content. This production process uses spent fuel material from a nuclear reactor and mainly comprising uranium, plutonium and fission products. An initial composite solution of this spent fuel material is produced and is pocessed to separate a solution of uranium and plutonium from the fission product solutions. The uranium and plutonium solution is processed to separate a plutonium solution and a solution of uranium is added to the last plutonium solution to produce a second composite solution. This uranium solution contains uranium sufficiently enriched for this second composite solution to have the preset fissile matter level. Finally a mixed nuclear fuel powder is produced from the solute of this second composite solution

79

Fuel cell  

International Nuclear Information System (INIS)

A fuel cell construction of economical design is disclosed. In the construction, a honeycomb separator is used to define a plurality of compartments which are separated from one another by a porous cell wall. Electrolyte is provided in the cell walls while alternate compartments of the cell contain either an oxidant or a fuel for the fuel cell. The cells contain suitable electrochemical catalyst materials on the walls thereof and electrode structures in the cells so that the oxidation of the fuel may take place in the electrolyte found in the cell walls in order to generate current for the cell. In accordance with preferred teachings, the separator is an extruded ceramic material such as used for the substrate of automotive catalytic converters

80

Fuel behaviour  

International Nuclear Information System (INIS)

A short summary of the main critical points in fuel performance of nuclear power reactors from chemical and mechanical point of view is given. A schedule for a limited research program is included. (author) 17 refs

 
 
 
 
81

Fuel reprocessing  

International Nuclear Information System (INIS)

The reprocessing of UO2 fuels from water cooled reactors is described. The process used (PUREX process) consists to dissolve the fuel in nitric acid, to separate the nitrates by solvent extraction with TBP diluted in dodecane and to purify U and Pu. The operation scheme is given. The processing of the wastes produced (fission products, gaseous, liquid and solid wastes) is presented. The cost of the reprocessing is analysed

82

Fuel rod  

International Nuclear Information System (INIS)

In a fuel rod of the present invention, Pd coating is applied on the inner surface of a fuel cladding tube made of zircaloy, further, a water getter is disposed at the upper end of the fuel. During operation of a reactor, namely, during irradiation of fuels, the cladding tube made of zircaloy undergoes corrosion at the outer surface thereof due to coolants at high temperature and high pressure, to form oxide membranes. In this case, hydrogen generated by the corrosion reaction is partially absorbed to the cladding tube made of zircaloy. The hydrogen reaches the surface thereof passing through the Pd coating, and positively reacts with oxygen to generate steams of H2O. Since generated water is absorbed to the water getter, it does not provide malfunctions to others. Further, since the inside of the fuel rod is generally in an oxidative atmosphere during combustion, there is no particular need for applying oxygen into coolants, so that there is no worry of promoting occurrence of stress corrosion cracks(SCC) of equipments other than fuels is promoted. (T.M.)

83

Canadian power reactor fuel  

International Nuclear Information System (INIS)

The following subjects are covered: the basic CANDU fuel design, the history of the bundle design, the significant differences between CANDU and LWR fuel, bundle manufacture, fissile and structural materials and coolants used in the CANDU fuel program, fuel and material behaviour, and performance under irradiation, fuel physics and management, booster rods and reactivity mechanisms, fuel procurement, organization and industry, and fuel costs. (author)

84

Nuclear fuel cycle  

International Nuclear Information System (INIS)

After a brief introduction on nuclear fuels and the different types of reactors the fuel cycle for PWR reactors is reviewed: uranium concentrate production, uranium hexafluoride conversion, uranium isotopic enrichment fuel fabrication, reprocessing, radioactive waste management, water reactor fuel market, fuel cycle economics, fuel cycle evolution. Finally the fuel cycle for other reactor types is briefly examined. 5 refs

85

Fuel cycle  

International Nuclear Information System (INIS)

The present CANDU fuel cycle is based on once-through natural uranium fuelling. Canadian uranium reserves will be more than adequate until the end of the century. Work is being carried out on advanced fuel cycles with two objectives: to provide a CANDU system capable of meeting energy needs safely, cleanly, at acceptable cost, and from available resources; and to provide utilities with the necessary assurance that long-term fuel supplies will be available when needed. The self-sufficient thorium-U233 cycle would require no continuing uranium supply. A successful demonstration of this cycle would put a ceiling on energy costs at a level no more than 25 % above present ones. The thorium cycle is no more complex than that for fast reactors. Technology required for the three components of the thorium cycle (fuel reprocessing, active fuel fabrication, and waste management) is already available. The development program should be roughly equivalent to the cost of one year's uranium consumption at the end of the century. (L.L.)

86

Alternative jet aircraft fuels  

Science.gov (United States)

Potential changes in jet aircraft fuel specifications due to shifts in supply and quality of refinery feedstocks are discussed with emphasis on the effects these changes would have on the performance and durability of aircraft engines and fuel systems. Combustion characteristics, fuel thermal stability, and fuel pumpability at low temperature are among the factors considered. Combustor and fuel system technology needs for broad specification fuels are reviewed including prevention of fuel system fouling and fuel system technology for fuels with higher freezing points.

Grobman, J.

1979-01-01

87

Reactor fuel  

International Nuclear Information System (INIS)

Fuel composed of Pu- or U- or Th-oxide compounds or combinations thereof plus additaments such as 2MgOx2Al2O3xSiO2 and Cs-graphite are apt for use in fast breeder reactors, PWR-type and BWR-type reactors as well as in GCR-type reactors. Additaments are used for gettering detrimental fission products and are chemically inert concerning their reaction with the fuel and cladding and they do not affect the nuclear fission chain reaction. (DG)

88

CANDU fuel  

International Nuclear Information System (INIS)

The direction of CANDU fuel development was set in 1957 with the decision to build pressure tube reactors. Short - 50 cm long - rodded bundles of natural UO2 clad in Zircaloy were adopted to facilitate on-power fuelling to improve uranium utilization. Progressive improvements were made during 25 years of development, involving 650 man years and 180 million dollars. Today's CANDU bundle is based on the knowledge gained from extensive irradiation testing and experience in power reactors. The main thrust of future development is to demonstrate that the present bundle is suitable, with minor modifications, for thorium fuels

89

Bunker Fuel Operations.  

Science.gov (United States)

The audit objectives were to determine wbether MSC collected fuel consumption data and submiitted bunker fuel requirements data to DFSC to support the continuation and establishment of bunker fuel contracts, and to determine whether existing bunker fuel c...

S. R. Young, J. S. Gebka, J. A. Gannon, B. T. Johnson, J. J. Delino

1995-01-01

90

Thorium fuel cycle management  

International Nuclear Information System (INIS)

In this presentation author deals with the thorium fuel cycle management. Description of the thorium fuels and thorium fuel cycle benefits and challenges as well as thorium fuel calculations performed by the computer code HELIOS are presented.

91

Fuel Cell Animation  

Science.gov (United States)

This fuel cell animation demonstrates how a fuel cell uses hydrogen to produce electricity, with only water and heat as byproducts. The animation consists of four parts - an introduction, fuel cell components, chemical process, and fuel cell stack.

Development, Us D.

92

Fuel oil poisoning  

Science.gov (United States)

Fuel oil poisoning occurs when someone swallows, breathes in (inhales), or touches fuel oil. This is for information only and not ... Fuel oil Kerosene Note: This list may not include all sources of fuel oil.

93

Fuel processing for fuel cells  

CERN Document Server

Adopting a unique integrated engineering approach, this text covers all aspects of fuel processing: catalysts, reactors, chemical plant components and integrated system design. While providing an introduction to the subject, it also contains recent research developments, making this an invaluable handbook for chemical, power and process engineers, electrochemists, catalytic chemists, materials scientists and engineers in power technology.

Kolb, Gunther

2008-01-01

94

Fuel assembly  

International Nuclear Information System (INIS)

Object: To ensure sufficient fall of reactor core spray water for effectively cooling the fuel rods even at the time of an accident, thereby preventing damage to the fuel cladding tube. Structure: A channel box is provided with a plurality of upper and lower holes, with the upper holes used as spray water flow outlets and the lower holes used as steam flow outlets. The upper holes are provided slightly above a support member for supporting the fuel rods, while the other holes are positioned below the support member. While the falling of the spray water is blocked at the position of the through-hole of the upper tie plate due to steam rising through the channel box at a high speed, the water collected on the tie plate is adapted to be discharged through the hole to the outside of the channel box, thus preventing the accumulation of the water on the tie plate and permitting smooth fall-down of the water. (Kamimura, M.)

95

Fuel element loading system  

International Nuclear Information System (INIS)

A nuclear fuel element loading system is described which conveys a plurality of fuel rods to longitudinal passages in fuel elements. Conveyor means successively position the fuel rods above the longitudinal passages in axial alignment therewith and adapter means guide the fuel rods from the conveyor means into the longitudinal passages. The fuel elements are vibrated to cause the fuel rods to fall into the longitudinal passages through the adapter means

96

An experimental study of steam explosions involving CORIUM melts  

International Nuclear Information System (INIS)

An experimental programme to investigate molten fuel coolant interactions involving 0.5 kg thermite-generated CORIUM melts and water has been carried out. System pressures and initial coolant subcoolings were chosen to enhance the probability of steam explosions. Yields and efficiencies of the interactions were found to be very close to those obtained from similar experiments using molten UO2 generated from a Uranium/Molybdenum Trioxide thermite. (author)

97

Maps showing distribution of pH, copper, zinc, fluoride, uranium, molybdenum, arsenic, and sulfate in water, Richfield 1 degree by 2 degrees Quadrangle, Utah  

Science.gov (United States)

These maps show the regional distribution of copper, zinc, arsenic, molybdenum, uranium, fluoride, sulfate, and pH in surface and ground water from the Richfield 1° x 2° quadrangle. This study supplements (Miller and others, 1984a-j) the regional drainage geochemical study done for the Richfield quadrangle under the U.S. Geological Survey’s Conterminuous United States Mineral Assessment Program (CUSMAP). Regional sampling was designed to define broad geochemical patterns and trends which can be used, along with geologic and geophysical data, to assess the mineral resource potential of the Richfield quadrangle. Analytical data used in compiling this report were published previously (McHugh and others, 1981). The Richfield quadrangle in west-central Utah covers the eastern part of the Pioche-Marysvale igneous and mineral belt that extends from the vicinity of Pioche in southeastern Nevada, east-northeastward for 250 km into central Utah. The western two-thirds of the Richfield quadrangle is in the Basin and Range Province, and the eastern third in the High Plateaus of Utah subprovince of the Colorado Plateau. Bedrock in the northern part of the Richfield quadrangle consists predominantly of latest Precambrian and Paleozoic sedimentary strata that were thrust eastward during the Sevier orogeny in Cretaceous time onto an autochthon of Mesozoic sedimentary rocks in the eastern part of the quadrangle. The southern part of the quadrangle is largely underlain by Oligocene and younger volcanic rocks and related intrusions. Extensional tectonism in late Cenozoic time broke the bedrock terrane into a series of north-trending fault blocks; the uplifted mountain areas were deeply eroded and the resulting debris deposited in the adjacent basins. Most of the mineral deposits in the Pioche-Marysvale mineral belt were formed during igneous activity in the middle and late Cenozoic time.

McHugh, J.B.; Miller, W.R.; Ficklin, W.H.

1984-01-01

98

76 FR 37703 - Regulation of Fuels and Fuel Additives: 2012 Renewable Fuel Standards; Public Hearing  

Science.gov (United States)

...FRL-9425-6] RIN 2060-AQ76 Regulation of Fuels and Fuel Additives: 2012 Renewable Fuel Standards; Public Hearing...for the proposed rule ``Regulation of Fuels and Fuel Additives: 2012 Renewable Fuel Standards,'' which...

2011-06-28

99

Fuel rod for nuclear fuel assembly  

International Nuclear Information System (INIS)

A cylindrical member made of a metal is disposed between fuel pellets and a plenum spring. The cylindrical metal member is made of the same material as a fuel cladding tube or a material having a smaller linear expansion coefficient than that of the cladding tube. If high pressure is exerted on a fuel rod, the fuel cladding tube is deformed at a plenum portion in which the plenum spring is disposed. The deformation is caused at the corner of the cylindrical metal member. Since the cylindrical metal member is softer than fuel pellets made of ceramics, there is no worry of breaking the fuel cladding tube at the corner. In addition, the corner of the cylindrical metal member is chamfered. Even if high pressure is exerted on the fuel rod, the fuel pellets can be sealed in the inside of the fuel cladding tube. (I.N.)

100

Nuclear fuel element assemblies  

International Nuclear Information System (INIS)

A fuel element assembly for a high temperature reactor comprises a prismatic block having fuel containing bores and interstitial coolant conducting bores extending end-to-end. The fuel comprises stacks of annular compacts which line the fuel containing bores and define central coolant flow channels through the fuel. (U.S.)

 
 
 
 
101

Fuel Cell Overview  

Science.gov (United States)

This presentation from Project Lead the Way Ohio looks at fuel cells. The origins of the technology, how fuel cells work and modern applications of fuel cell technologies are discussed. Information on different types of fuel cells and their potential use in fueling automobiles is also included. This document may be downloaded in Microsoft PowerPoint file format.

2012-08-30

102

Fuel assembly  

International Nuclear Information System (INIS)

The fuel assembly of the present invention can prevent aging change in leaking the flow rate of coolants between a lower tie plate and a channel box. That is, the thickness of inner walls of the lower tie plate at the position corresponding to the lower end of the channel box of the lower tie plate is increased. A plurality of orifice-like through holes are disposed on the circumferential side of the portion with increased thickness. Further, since the flow channel of coolants is restricted by the portion with increased thickness, the pressure in the flow channel is lowered. Accordingly, the pressure on the inside of the lower tie plate at the restricted channel is made lower than the pressure on the outer side by controlling the cross sectional area of the flow channel. Further, by disposing a plurality of orifice-like through holes, the pressure difference between the inner and the outer sides can be controlled depending on the outer pressure. As a result, the distance between the lower tie plate and the channel box can be kept appropriately irrespective of the burnup degree and the reactor staying time of fuels. (I.S.)

103

Constant strength fuel-fuel cell  

International Nuclear Information System (INIS)

A fuel cell is an electrochemical apparatus composed of both a nonconsumable anode and cathode; and electrolyte, fuel oxidant and controls. This invention guarantees the constant transfer of hydrogen atoms and their respective electrons, thus a constant flow of power by submergence of the negative electrode in a constant strength hydrogen furnishing fuel; when said fuel is an aqueous absorbed hydrocarbon, such as and similar to ethanol or methnol. The objective is accomplished by recirculation of the liquid fuel, as depleted in the cell through specific type membranes which pass water molecules and reject the fuel molecules; thus concentrating them for recycle use

104

Fuel processors for fuel cell APU applications  

Science.gov (United States)

The conversion of liquid hydrocarbons to a hydrogen rich product gas is a central process step in fuel processors for auxiliary power units (APUs) for vehicles of all kinds. The selection of the reforming process depends on the fuel and the type of the fuel cell. For vehicle power trains, liquid hydrocarbons like gasoline, kerosene, and diesel are utilized and, therefore, they will also be the fuel for the respective APU systems. The fuel cells commonly envisioned for mobile APU applications are molten carbonate fuel cells (MCFC), solid oxide fuel cells (SOFC), and proton exchange membrane fuel cells (PEMFC). Since high-temperature fuel cells, e.g. MCFCs or SOFCs, can be supplied with a feed gas that contains carbon monoxide (CO) their fuel processor does not require reactors for CO reduction and removal. For PEMFCs on the other hand, CO concentrations in the feed gas must not exceed 50 ppm, better 20 ppm, which requires additional reactors downstream of the reforming reactor. This paper gives an overview of the current state of the fuel processor development for APU applications and APU system developments. Furthermore, it will present the latest developments at Fraunhofer ISE regarding fuel processors for high-temperature fuel cell APU systems on board of ships and aircrafts.

Aicher, T.; Lenz, B.; Gschnell, F.; Groos, U.; Federici, F.; Caprile, L.; Parodi, L.

105

KMRR fuel design  

International Nuclear Information System (INIS)

KMRR fuel rod design criteria on fuel swelling, blistering and oxide spallation have been reexamined. Fuel centerline temperature limit of 250deg C in normal operation condition and fuel swelling limit of 12 % at the end of life have been proposed to prevent fuel failure due to excessive fuel swelling. Fuel temperature limit of 485deg C has been proposed to exclude the possibility of fuel failures during transients or under accident condition. Further analyses are needed to decide the fuel cladding temperature limit to preclude the oxide spallation. Design changes in fuel assembly structure and their effects on related systems have been reviewed from a structural integrity viewpoint. The remained works in fuel mechanical design area have been identified and further efforts of fuel design group will be focused on these aspects. (Author)

106

HTGR reactor fuel  

International Nuclear Information System (INIS)

A critical review is given of data on the physical, chemical end other relevant properties of fuel materials and fuel elements for HTGR reactors. Available technologies for coated particles and fuel elements fabrication and appropriate quality control are described. In-core fuel behavior and spent fuel reprocessing are briefly discussed. Basic information about uranium and thorium fuel cycles is included. (author). 17 figs., 21 tabs., 87 refs

107

Dispersion fuel element fabrication  

International Nuclear Information System (INIS)

Peculiarities of dispersion fuel element fabrication are discussed. Methods of fuel rod fabrication, cladding and fuel element sealing are considered. Technology of fuel element fabrication by the methods of melting and casting, powder metallurgy is described in detail along with the methods of metallic, ceramic, and graphite coating on fuel microparticles. It is noted that in the process of fuel element fabrication emphasis is placed upon technological control of their quality

108

Fuel handling method  

International Nuclear Information System (INIS)

In a method of handling MOX fuels transferred in a state being contained in a fuel transferring vessel to a reactor building, when they are transferred from the fuel casks to a fuel erection stand, they are transferred in a state where the MOX fuels are covered by a shielding member for shielding radiation emitted from the MOX fuels. In addition, when they are transferred from the fuel casks to a fuel detection device, they are transferred also in a state being covered by a shielding member in the same manner. Since they are transferred in a state where they are covered by a shielding member for shielding radiation emitted from the MOX fuels, operation can be conducted in a circumstance where radiation is shielded sufficiently, and an operator's radiation exposure can be reduced. In addition, since MOX fuels can be handled in the same manner as uranium fuels, the workability is not deteriorated. (N.H.)

109

A BWR fuel assembly  

International Nuclear Information System (INIS)

A boiling water nuclear reactor used for the production of electricity includes fuel rods and an assembly of these fuel rods that improve the reactor economics and safety. The fuel assemblies include hydride fuel pellets at selected axial and radial positions in addition to oxide fuel pellets. The hydride fuel functions simultaneously as fuel and as a moderator. The hydride fuel can be made from different combinations of fissionable materials such as uranium, and hydrides such as zirconium hydride. The fuel (such as U-ZrH1.6) is substituted for oxide fuel (UO2) in undermoderated regions of the core. Hydride fuel rods also replace water rods in the fuel assemblies. The use of hydrogen containing fuel rods and fuel assemblies enable flattening the power distribution across the fuel assembly and across the core; reducing the need for power shaping and reactivity control with burnable poisons and control rods; improving the nuclear fuel utilization; increasing the reactor availability; increasing the safety factors for fuel meltdown accidents or, alternatively, increasing the power output from a given core size; reducing the cold shutdown reactivity margin; and reducing the leakage of neutrons from the core. (author) figs

110

Fuel manufacturing and utilization  

International Nuclear Information System (INIS)

The efficient utilisation of nuclear fuel requires manufacturing facilities capable of making advanced fuel types, with appropriate quality control. Once made, the use of such fuels requires a proper understanding of their behaviour in the reactor environment, so that safe operation for the design life can be achieved. The International Atomic Energy Agency supports Member States to improve in-pile fuel performance and management of materials; and to develop advanced fuel technologies for ensuring reliability and economic efficiency of the nuclear fuel cycle. It provides assistance to Member States to support fuel-manufacturing capability, including quality assurance techniques, optimization of manufacturing parameters and radiation protection. The IAEA supports the development fuel modelling expertise in Member States, covering both normal operation and postulated and severe accident conditions. It provides information and support for the operation of Nuclear Power Plant to ensure that the environment and water chemistry is appropriate for fuel operation. The IAEA supports fuel failure investigations, including equipment for failed fuel detection and for post-irradiation examination and inspection, as well as fuel repair, it provides information and support research into the basic properties of fuel materials, including UO2, MOX and zirconium alloys. It further offers guidance on the relationship with back-end requirement (interim storage, transport, reprocessing, disposal), fuel utilization and management, MOX fuels, alternative fuels and advanced fuel technology

111

Instrumentation of fuel elements and fuel plates  

International Nuclear Information System (INIS)

When controlling the behaviour of a reactor or developing a new fuel concept, it is of utmost interest to have the possibility to confirm the thermohydraulic calculations by actual measurements in the fuel elements or in the fuel plates. For years, CERCA has developed the technology and supplied its customers with fuel elements equipped with pressure or temperature measuring devices according to the requirements. Recent customer projects have led to the development of a new method to introduce thermocouples directly into the fuel plate meat instead of the cladding. The purpose of this paper is to review the various instrumentation possibilities available at CERCA. (author)

112

Instrumentation of fuel elements and fuel plates  

International Nuclear Information System (INIS)

When controlling the behaviour of a reactor or developing a new fuel concept, it is of utmost interest to have the possibility to confirm the thermohydraulic calculations by actual measurements in the fuel elements or in the fuel plates. For years, CERCA has developed the technology and supplied its customers with fuel elements equipped with pressure or temperature measuring devices according to the requirements. Recent customer projects have lead to the development of a new method to introduce thermocouples directly into the fuel plate meat instead of the cladding. The purpose of this paper is to review the various instrumentation possibilities available at CERCA. (author)

113

HTGR fuel and fuel cycle technology  

International Nuclear Information System (INIS)

Significant advances have occurred in the development of HTGR fuel and fuel cycle. These accomplishments permit a wide choice of fuel designs, reactor concepts, and fuel cycles. Fuels capable of providing helium outlet temperatures of 7500C are available, and fuels capable of 10000C outlet temperatures may be expected from extension of present technology. Fuels have been developed for two basic HTGR designs, one using a spherical (pebble bed) element and the other a prismatic element. Within each concept a number of variations of geometry, fuel composition, and structural materials are permitted. Potential fuel cycles include both low-enriched and high-enriched Th-235U, recycle Th-233U, and Th-Pu or U-Pu cycles. This flexibility offered by the HTGR is of great practical benefit considering the rapidly changing economics of power production. The inflation of ore prices has increased optimum conversion ratios, and increased the necessity of fuel recycle at an early date. Fuel element makeup is very similar for prismatic and spherical designs. Both use spherical fissile and fertile particles coated with combinations of pyrolytic carbon and silicon carbide. Both use carbonaceous binder materials, and graphite as the structural material. Weak-acid resin (WAR) UO2-UC2 fissile fuels and sol-gel-derived ThO2 fertile fuels have been selected for the Th-233U cycle in the prismatic design. Sol-gel-derived UO2UC2 is the reference fissile fuel for the low-enriched pebble bed design. Both the United States and Federal Republic of Germany are developing technology for fuel cycle operations including fabrication, reprocessing, refabrication, and waste handling. Feasibility of basic processes has been established and designs developed for full-scale equipment. Fuel and fuel cycle technology provide the basis for a broad range of applications of the HTGR. Extension of the fuels to higher operating temperatures and development and commercial demonstration of fuel cycle equipment and facilities remain to be accomplished so that maximum advantage can be taken of the inherent capabilities of the HTGR

114

Integrated fuel processor development  

International Nuclear Information System (INIS)

The Department of Energy's Office of Advanced Automotive Technologies has been supporting the development of fuel-flexible fuel processors at Argonne National Laboratory. These fuel processors will enable fuel cell vehicles to operate on fuels available through the existing infrastructure. The constraints of on-board space and weight require that these fuel processors be designed to be compact and lightweight, while meeting the performance targets for efficiency and gas quality needed for the fuel cell. This paper discusses the performance of a prototype fuel processor that has been designed and fabricated to operate with liquid fuels, such as gasoline, ethanol, methanol, etc. Rated for a capacity of 10 kWe (one-fifth of that needed for a car), the prototype fuel processor integrates the unit operations (vaporization, heat exchange, etc.) and processes (reforming, water-gas shift, preferential oxidation reactions, etc.) necessary to produce the hydrogen-rich gas (reformate) that will fuel the polymer electrolyte fuel cell stacks. The fuel processor work is being complemented by analytical and fundamental research. With the ultimate objective of meeting on-board fuel processor goals, these studies include: modeling fuel cell systems to identify design and operating features; evaluating alternative fuel processing options; and developing appropriate catalysts and materials. Issues and outstanding challenges that need to be overcome in order to develop practical, on-boarome in order to develop practical, on-board devices are discussed

115

Treat upgrade fuel fabrication  

International Nuclear Information System (INIS)

An extrusion and thermal treatment process was developed to produce graphite fuel rods containing a dispersion of enriched UO2. These rods will be used in an upgraded version of the Transient Reactor Test Facility (TREAT). The improved fuel provides a higher graphite matrix density, better fuel dispersion and higher thermal capabilities than the existing fuel

116

Fuel Cells Fact Sheet  

Science.gov (United States)

This document provides a basic introduction to fuel cells: how they work, the different types of fuel cells (PEM, AFC, PAFC, DMFC, MCFC and SOFC) and the advantages and disadvantages of using fuel cells. Two useful graphic representations of fuel cells are also included. This document may be downloaded in PDF file format.

2012-09-18

117

Fuel charging machines  

International Nuclear Information System (INIS)

Purpose: To improve the workability and safety by enabling the machine to check the subcritical state while loading the fuel assembly upon fuel charging. Constitution: A process computer for calculating subcriticality degree is provided in the fuel charging machine, which is connected to a nuclear reactor. When it is judged the state to be subcritical, a fueling-possible signal is sent to the fuel charging machine. On the contrary, when it is not, fueling-stop or other position-selection signal is sent to the fuel charging machine. (J.P.N.)

118

Fuel transfer system  

Science.gov (United States)

A nuclear fuel bundle fuel transfer system includes a transfer pool containing water at a level above a reactor core. A fuel transfer machine therein includes a carriage disposed in the transfer pool and under the water for transporting fuel bundles. The carriage is selectively movable through the water in the transfer pool and individual fuel bundles are carried vertically in the carriage. In a preferred embodiment, a first movable bridge is disposed over an upper pool containing the reactor core, and a second movable bridge is disposed over a fuel storage pool, with the transfer pool being disposed therebetween. A fuel bundle may be moved by the first bridge from the reactor core and loaded into the carriage which transports the fuel bundle to the second bridge which picks up the fuel bundle and carries it to the fuel storage pool. 6 figures.

Townsend, H.E.; Barbanti, G.

1994-03-01

119

Nuclear fuel elements  

International Nuclear Information System (INIS)

Purpose: To prevent chemical interactions between fuel cans and corrosive fission products and prevent brittle fracture in the fuel cans in fuel elements for water cooled reactors and FBR type reactors. Constitution: Fiberous quartz glass is put between zircalloy or stainless steel fuel cans and fuel pellets. The quartz glass is chemically stable and reacts neither with the fuel can not with the fuel pellets even under long irradiation in the nuclear reactor. Since fission products released from the inside of the fuel pellets are physically adsorbed on the fiberous quartz glass, most of them do not reach the inner surface of the fuel cans, whereby the chemical interactions between the corrosive fission products and the fuel cans can be decreased. (Ikeda, J.)

120

Fuel cells seminar  

Energy Technology Data Exchange (ETDEWEB)

This year`s meeting highlights the fact that fuel cells for both stationary and transportation applications have reached the dawn of commercialization. Sales of stationary fuel cells have grown steadily over the past 2 years. Phosphoric acid fuel cell buses have been demonstrated in urban areas. Proton-exchange membrane fuel cells are on the verge of revolutionizing the transportation industry. These activities and many more are discussed during this seminar, which provides a forum for people from the international fuel cell community engaged in a wide spectrum of fuel cell activities. Discussions addressing R&D of fuel cell technologies, manufacturing and marketing of fuel cells, and experiences of fuel cell users took place through oral and poster presentations. For the first time, the seminar included commercial exhibits, further evidence that commercial fuel cell technology has arrived. A total of 205 papers is included in this volume.

NONE

1996-12-01

 
 
 
 
121

Repositioned fuel assembly  

International Nuclear Information System (INIS)

This patent describes a nuclear reactor having a core with discrete replaceable identical fuel assemblies, the fuel assemblies being supported on a lower core plate and held in vertically upstanding relation at an upper top guide, each fuel assembly including, a lower tie plate for support from the core plate, an upper tie plate, the fuel rods between the upper and lower tie plates, and a square section fuel channel surrounding the lower tie plate

122

BWR fuel performance  

International Nuclear Information System (INIS)

The General Electric experience base on BWR fuel includes over 29,000 fuel assemblies which contain 1,600,000 fuel rods. Over the last five years, design, process and operating changes have been introduced which have had major effects in improving fuel performance. Monitoring this fuel performance in BWRs has been accomplished through cooperative programs between GE and utilities. Activities such as plant fission product monitoring, fuel sipping and fuel and channel surveillance programs have jointly contributed to the value of this extensive experience base. The systematic evaluation of this data has established well-defined fuel performance trends which provide the assurance and confidence in fuel reliability that only actual operating experience can provide

123

Alternative aircraft fuels  

Science.gov (United States)

In connection with the anticipated impossibility to provide on a long-term basis liquid fuels derived from petroleum, an investigation has been conducted with the objective to assess the suitability of jet fuels made from oil shale and coal and to develop a data base which will allow optimization of future fuel characteristics, taking energy efficiency of manufacture and the tradeoffs in aircraft and engine design into account. The properties of future aviation fuels are examined and proposed solutions to problems of alternative fuels are discussed. Attention is given to the refining of jet fuel to current specifications, the control of fuel thermal stability, and combustor technology for use of broad specification fuels. The first solution is to continue to develop the necessary technology at the refinery to produce specification jet fuels regardless of the crude source.

Longwell, J. P.; Grobman, J.

1978-01-01

124

Dual Tank Fuel System  

Science.gov (United States)

A dual tank fuel system has primary and secondary fuel tanks, with the primary tank including a filler pipe to receive fuel and a discharge line to deliver fuel to an engine, and with a balance pipe interconnecting the primary tank and the secondary tank. The balance pipe opens close to the bottom of each tank to direct fuel from the primary tank to the secondary tank as the primary tank is filled, and to direct fuel from the secondary tank to the primary tank as fuel is discharged from the primary tank through the discharge line. A vent line has branches connected to each tank to direct fuel vapor from the tanks as the tanks are filled, and to admit air to the tanks as fuel is delivered to the engine.

Wagner, Richard William (Albion, NY); Burkhard, James Frank (Churchville, NY); Dauer, Kenneth John (Avon, NY)

1999-11-16

125

DUPIC fuel compatibility assessment  

International Nuclear Information System (INIS)

The purpose of this study is to assess the compatibility of DUPIC (Direct Use of Spent PWR Fuel in CANDU Reactors) fuel with the current CANDU 6 reactor, which is one of the technology being developed to utilize the spent PWR fuel in CANDU reactors. The Phase II study of this project includes the analysis of impact on the reactor safety, the development of core design technology, the development of fuel supply technology of optimal composition, and feasibility analysis on localization and license of DUPIC fuel. From the reactor safety analysis results, it is known that DUPIC fuel satisfies the safety limit of reactor containment and public dose for single failure. But, the safety limit may be exceeded for dual failure. Therefore, more analysis is needed for the removal of excessive conservatism in accident analysis methodology and modification of transient fuel behavior analysis methodology. The results of the validation calculations of core design methodology have confirmed that the current core analysis system is acceptable for the feasibility study of the DUPIC fuel compatibility analysis. The results of compatibility and fuel fabrication have shown that DUPIC fuel is technically feasible. For practical use and licensing, however, more research items required in the practical use, fuel rod and bundle design and fuel loading are should be performed. When these items are performed and resolved, the compatibility of the DUPIC fuel is achieved, and, eventually, the possibility of DUPIC fuel licensing can be confirmed

126

MOX fuel assembly  

International Nuclear Information System (INIS)

The fuel assembly of the present invention comprises at least one water rod, first fuel rods filled with uranium/plutonium mixed oxide fuels, second fuel rods having axial length shorter than that of the first fuel rods and third fuel rods containing burnable poisons. If the third fuel rods are arranged on the same row and adjacent columns or on the same column and adjacent row relative to the positions where the second fuel rods are arranged or the position of the water rod replacing fuel rods, in other words, at a position extremely close to them, neutron spectrum is made softer and the neutron flux distribution is made higher. As a result, negative reactivity worth of the burnable poisons contained in the third fuel rods is enhanced, accordingly, a reactivity suppression effect comparable with that in conventional cases can be obtained by so much even if the number of the third fuel rods is reduced. The number of the MOX fuel rods is increased than a conventional case by so much as replacing the third fuel rods with the MOX fuel rods by the reduced amount thereby enabling to improve the efficiency using plutonium. (N.H.)

127

Micro fuel cell  

Energy Technology Data Exchange (ETDEWEB)

An ambient temperature, liquid feed, direct methanol fuel cell device is under development. A metal barrier layer was used to block methanol crossover from the anode to the cathode side while still allowing for the transport of protons from the anode to the cathode. A direct methanol fuel cell (DMFC) is an electrochemical engine that converts chemical energy into clean electrical power by the direct oxidation of methanol at the fuel cell anode. This direct use of a liquid fuel eliminates the need for a reformer to convert the fuel to hydrogen before it is fed into the fuel cell.

Zook, L.A.; Vanderborgh, N.E. [Los Alamos National Lab., NM (United States); Hockaday, R. [Energy Related Devices Inc., Los Alamos, NM (United States)

1998-12-31

128

Fuel Cells: Green Power  

Science.gov (United States)

This online report, written in 2006, provides a comprehensive overview of fuel cell technology. In layman's terms, it gives a brief history, compares various types of fuel cells, and discusses environmental implications of using hydrogen as a fuel. For teachers and learners of physics, this publication explains the process by which fuel cells convert chemical energy directly to electrical energy, resulting in greater fuel efficiency and reduction of emissions. One chapter is devoted to an in-depth exploration of the PEM (polymer electrolyte membrane) fuel cell, which is being widely studied for use in automobiles.

Thomas, Sharon; Zalbowitz, Marcia; Gill, Dennis

2007-11-29

129

Nuclear fuel activities in Belgium  

International Nuclear Information System (INIS)

In his presentation on nuclear fuel activities in belgium the author considers the following directions of this work: fuel fabrication, NPP operation, fuel performance, research and development programmes

130

DUPIC fuel compatibility assessment  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study is to assess the compatibility of DUPIC(Direct Use of Spent PWR Fuel in CANDU Reactors) fuel with the current CANDU 6 reactor, which is one of the technology being developed to utilize the spent PWR fuel in CANDU reactors. The phase 1 study of this project includes the feasibility analysis on applicability of the current core design method, the feasibility analysis on operation of the DUPIC fuel core, the compatibility analysis on individual reactor system, the sensitivity analysis on the fuel composition, and the economic analysis on DUPIC fuel cycle. The results of the validation calculations have confirmed that the current core analysis system is acceptable for the feasibility study of the DUPIC fuel compatibility analysis. The results of core simulations have shown that both natural uranium and DUPIC fuel cores are almost the same from the viewpoint of the operational performance. For individual reactor system including reactively devices, the functional requirements of each system are satisfied in general. However, because of the pronounced power flattening in the DUPIC core, the radiation damage on the critical components increases, which should be investigated more in the future. The DUPIC fuel composition heterogeneity dose not to impose any serious effect on the reactor operation if the fuel composition is adjusted. The economics analysis has been performed through conceptual design studies on the DUPIC fuel fabrication, fuel handling in a plant, and spent fuel disposal, which has shown that the DUPIC fuel cycle is comparable to the once-trough fuel cycle considering uncertainties associated with unit costs of the fuel cycle components. The results of Phase 1 study have shown that it is feasible to use the DUPIC fuel in CANDU reactors without major changes in hardware. However further studies are required to confirm the safety of the reactor under accident condition.

Choi, Hang Bok; Rho, G. H.; Park, J. W. [and others

2000-03-01

131

Reactor fuel replacement system  

International Nuclear Information System (INIS)

Object: To reduce exposure of radiation and increase the efficiency of a fuel rod replacement operation by dividing the fuel storage pool into a plurality of regions depending upon the position of a fuel rack, determining a fixed point in each of the regions and moving the fuel rod through a straight route up to a fixed point. Structure: A fuel storage pool is divided into a plurality of regions depending upon the position of a fuel rack, a fixed position is determined for each of these regions, and the above items are memorized by an electronic computer such that the fuel rod can be moved through a straight route to each of the fixed points. Thus, when the fuel replacement unit is moved from the fuel storage pool through a gate, it is moved to a fixed point by simultaneously moving its two axes, namely x- and y-axes, such that it is moved along a straight route of the smallest distance from a region, to which a fuel rack of a fuel rod to be moved belongs, to a fixed point preset in the neighborhood of the entrance of a gate corresponding to the relevant region. Thereafter, the fuel replacement is moved from a stationary point to the core pool, to thereby effect replacement of the fuel rod. (Moriyama, K.)

132

Romanian nuclear fuel program  

International Nuclear Information System (INIS)

an fuel supplier for CANDU-6 reactors, 202 fuel bundles were produced. Of these fuel bundles, 66 were part of the Cernavoda NGS Unit 1 first fuel load (the balance was supplied by Zircatec Precision Industries Inc. ZPI). The industrial nuclear fuel fabrication re-started in Romania in January 1995 under AECL's periodical monitoring. In December 1995, AECL issued a permanent certificate, stating the Romanian nuclear fuel plant as a qualified and authorised CANDU-6 fuel supplier. The re-loading of the Cernavoda NGS Unit 1 started in the middle of January 1997 with fuel produced by the Romanian fuel plant. The quality evaluation of the 'pre-1990' fuel started in April 1996 and was performed by the Nuclear Fuel Plant (FCN) Pitesti, under the supervision of the Nuclear Power Group (GEN) - a distinct department of RENEL. The paper presents the involvement of Romania in the activities related to the Advanced CANDU Fuel Cycle. The future prospect and trend of the Romanian Nuclear Fuel Program are also presented in this paper. (author)

133

Fuel Assembly Damping Summary  

Energy Technology Data Exchange (ETDEWEB)

This paper summary the fuel assembly damping data in air/in still water/under flow, released from foreign fuel vendors, compared our data with the published data. Some technical issues in fuel assembly damping measurement testing are also briefly discussed. Understanding of each fuel assembly damping mechanisms according to the surrounding medium and flow velocity can support the fuel design improvement in fuel assembly dynamics and structural integrity aspect. Because the upgraded requirements of the newly-developed advanced reactor system will demands to minimize fuel design margin in integrity evaluation, reduction in conservatism of fuel assembly damping can contribute to alleviate the fuel design margin for sure. Damping is an energy dissipation mechanism in a vibrating mechanical structure and prevents a resonant structure from having infinite vibration amplitudes. The sources of fuel assembly damping are various from support friction to flow contribution, and it can be increased by the viscosity or drag of surrounding fluid medium or the average velocity of water flowing. Fuel licensing requires fuel design evaluation in transient or accidental condition. Dynamic response analysis of fuel assembly is to show fuel integrity and requires information on assembly-wise damping in dry condition and under wet or water flowing condition. However, damping measurement test for the full-scale fuel assembly prototype is not easy to carry out because of the scale (fuel prototype, test facility), unsteadiness of test data (scattering, random sampling and processing), instrumentation under water flowing (water-proof response measurement), and noise. LWR fuel technology division in KAERI is preparing the infra structure for damping measurement test of full-scale fuel assembly, to support fuel industries and related research activities. Here is a preliminary summary of fuel assembly damping, published in the literature. Some technical issues in fuel assembly damping measurement testing under flow are also briefly discussed. Fuel assembly damping is an essential parameter to determine fuel assembly dynamic behavior in operating or accidental core. Dry damping coefficient from the out-pile pluck testing was used for the accident analysis model in conservative and simplified manner. But, this is way lower than wet or under-flow damping.

Lee, Kanghee; Kang, Heungseok; Oh, Dongseok; Yoon, Kyungho; Kim, Hyungkyu; Kim, Jaeyong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2013-10-15

134

Zero-failure fuel  

International Nuclear Information System (INIS)

debris fretting as primary failure cause on ABB 10 x 10 fuel. ABB has now a very good understanding of the cause of primary failures and the generic fuel degradation mechanisms. Based on this understanding, ABB has developed effective remedies both against debris fretting and fuel rod degradation. These remedies include fretting resistant cladding, mitigating of debris from the primary system and fuel assemblies, operation guide lines for operation with a primary leaker in core and other efficient remedies against degradation and fuel washout etc. Immediate and accurate fuel failure detection is also very important for the operation of a nuclear power plant, as well as correct evaluation of fuel failure type and severity. ABB has therefore developed an on-line nuclide specific off-gas monitoring system designed to evaluate the integrity of nuclear fuel by analyzing the activity levels of the reactor off-gas. (authors)

135

Bunker Fuel Payments.  

Science.gov (United States)

Bunker fuel is used to propel seagoing vessels and is stored in compartments, called bunkers, on shipboard. Mission requirements sometimes require that DoD-controlled vessels obtain bunker fuel at commercial ports in the continental United States or overs...

1995-01-01

136

Future automotive fuels  

International Nuclear Information System (INIS)

There are several important factors which are fundamental to the choice of alternative automobile fuels: the chain of energetic efficiency of fuels; costs; environmental friendliness; suitability for usual engines or adapting easiness; existing reserves of crude oil, natural gas or the fossil energy sources; and, alternatively, agricultural potentiality. This paper covers all these factors. The fuels dealt with in this paper are alcohol, vegetable oil, gaseous fuel, hydrogen and ammonia fuels. Renewable fuels are the most valuable forms of renewable energy. In addition to that rank, they can contribute to three other problem areas: agricultural surpluses, environmental degradation, and conservation of natural resources. Due to the competitive utilization of biomass for food energy production, bio-fuels should mainly be produced in those countries where an energy shortage is combined with a food surplus. The fuels arousing the most interest are alcohol and vegetable oil, the latter for diesel engines, even in northern countries. (au)

137

Reformulated diesel fuel  

Science.gov (United States)

Reformulated diesel fuels for automotive diesel engines which meet the requirements of ASTM 975-02 and provide significantly reduced emissions of nitrogen oxides (NO.sub.x) and particulate matter (PM) relative to commercially available diesel fuels.

McAdams, Hiramie T [Carrollton, IL; Crawford, Robert W [Tucson, AZ; Hadder, Gerald R [Oak Ridge, TN; McNutt, Barry D [Arlington, VA

2006-03-28

138

Nuclear fuel element  

International Nuclear Information System (INIS)

Purpose: To completely prevent stress-corrosion cracking failure of a fuel can constituting a nuclear fuel element. Constitution: Super plastic material such as Zn-22Al is applied with super plastification processing by gradual cooling from a temperature higher than its eutectic point. Super plastic material layers show a high ductility under lower stresses. Accordingly, when they are bonded metallurgically to the inner surface of a fuel can, if mechanical inter actions are caused between nuclear fuel pellet and a fuel can, the stress level at the inner surface layer of the fuel can does not reach such a level as causing stress corrosion cracking. Accordingly, in the nuclear fuel element according to the present invention, no stress-corrosion cracking occurs in the fuel can, thereby enabling to obtain highly reliabile products. (Takahashi, M.)

139

Biodegradation of biodiesel fuels  

International Nuclear Information System (INIS)

ce fuel. No significant difference was noted for COD values between test substances and the control fuel. (p > 0.20). The D-2 control substance was significantly lower than all test substances for BCD, values at p 5 value

140

Alternative aircraft fuels technology  

Science.gov (United States)

NASA is studying the characteristics of future aircraft fuels produced from either petroleum or nonpetroleum sources such as oil shale or coal. These future hydrocarbon based fuels may have chemical and physical properties that are different from present aviation turbine fuels. This research is aimed at determining what those characteristics may be, how present aircraft and engine components and materials would be affected by fuel specification changes, and what changes in both aircraft and engine design would be required to utilize these future fuels without sacrificing performance, reliability, or safety. This fuels technology program was organized to include both in-house and contract research on the synthesis and characterization of fuels, component evaluations of combustors, turbines, and fuel systems, and, eventually, full-scale engine demonstrations. A review of the various elements of the program and significant results obtained so far are presented.

Grobman, J.

1976-01-01

 
 
 
 
141

Center for Alternative Fuels  

Science.gov (United States)

The success of the HEV programs under this grant prompted Macomb to launch this resource, the Center for Alternative Fuels. The center holds forums in which academic and industry experts discuss the technical and societal impact of alternative fuels.

2009-12-21

142

Loviisa nuclear fuel service  

International Nuclear Information System (INIS)

The nuclear fuel service of the both units of Loviisa NPS is based on longterm fresh fuel purchasing contracts and longterm spent fuel return contracts. These contracts belong to the Soviet delivery package of Loviisa NPS and they have been made separately for the both units for their whole lifetime. The Soviet contract party is v/o Techsnabexport. Fresh fuel is ordered at the beginning of the year preceding the delivery year. The delivery takes place about one and half years earlier than the fuel is loaded into reactor. The irradiation time of the fuel is typically three years (partly two years). Spent fuel is stored at site in different storage pools five years before its returning to tbe Soviet Union. Altogether the nuclear fuel is staying at Loviisa about ten years

143

Fuel cycle data survey  

International Nuclear Information System (INIS)

A survey of the fuel cycle cost data published during 1977 and 1978 is presented in tabular and graphical form. Cost trends for the period 1965 onwards are presented for yellow cake, conversion, uranium enrichment, fuel fabrication and reprocessing

144

EOS Reactor Fuel  

International Science & Technology Center (ISTC)

Development of the Equations of State for Fuel Compositions, which Take into Account the Microstructure Accumulation Kinetics its Use for Simulation of the Fuel Failure Consequences in Nuclear Reactors of VariousType. (Continuation of the project 003)

145

Fuel Cell Applications  

Science.gov (United States)

This page uses flash animation to briefly explain the many areas where fuel cell technology can be applied. It also discusses the need for alternative energies as well as outlines the advantages of fuel cells.

2012-09-11

146

Nuclear fuel rods  

International Nuclear Information System (INIS)

Purpose: To increase the life of nuclear fuel rods by suppressing the ruptures due to strees corrosion cracks, as well as eliminate the requirement for conditioning operation to prolong the period for the operation cycle. Constitution: Getter materials in a thin disc configuration having a fission gas product absorbing performance and with an outer circumferential diameter substantially equal to the fuel pellet are put between fuel pelltes at specified several positions. Accordingly, fission gas products resulted upon burnup of fuel pellets can effectively be absorbed near the position of this generation without altering other design structure of the fuel rods, to thereby prevent the stress corrosion cracks to the fuel can due to the synergistic effect of the pellet-cladding tube interaction and the fission gas products and thus the destruction of the nuclear fuel rods, whereby the working life of the nuclear fuel rod can be increased. (Yoshihara, H.)

147

Jet fuel instability mechanisms  

Science.gov (United States)

The mechanisms of the formation of fuel-insoluble deposits were studied in several real fuels and in a model fuel consisting of tetralin in dodecane solution. The influence of addition to the fuels of small concentrations of various compounds on the quantities of deposits formed and on the formation and disappearance of oxygenated species in solution was assessed. The effect of temperature on deposit formation was also investigated over the range of 308-453 K.

Daniel, S. R.

1985-01-01

148

Nuclear reactor fuel element  

International Nuclear Information System (INIS)

In order to reduce the fuel can casting one of the fuel rods has two supports, displaced relative to each other in the axial direction on the outside, between which a spacer is positioned. A lock is connected to be form-locking with the lower end of the fuel rod having the supports, which is situated transversely through the axial falling path of other fuel rods and limits axial movement in the direction of falling. (orig./HP)

149

Nuclear fuel cycle  

International Nuclear Information System (INIS)

Different technical and economical issues of nuclear fuel cycle are discussed, including world uranium market; uranium market price; uranium production, resources and exploration; future trends in uranium supply and demand; uranium conversion, enrichment; reactor fuel technology; control materials for water reactors; spent fuel management; prospects of plutonium use as nuclear fuel. IAEA work in this area was also highlighted. 14 refs, 10 figs, 17 tabs

150

Fuel cell electronics packaging  

CERN Document Server

Today's commercial, medical and military electronics are becoming smaller and smaller. At the same time these devices demand more power and currently this power requirement is met almost exclusively by battery power. This book includes coverage of ceramic hybrid separators for micro fuel cells and miniature fuel cells built with LTCC technology. It also covers novel fuel cells and discusses the application of fuel cell in microelectronics.

Kuang, Ken

2007-01-01

151

Fuel Pumping Station-Palmer  

Science.gov (United States)

... of a new fuel transfer system between Palmer's two 473,000-liter (125,000-gallon) bulk fuel storage ... pump to transfer fuel between tanks. The new pump would also be used to mix fuel which may become ...

152

Thorium fuel cycles  

International Nuclear Information System (INIS)

Thorium fuel cycles for light-water reactors, heavy-water CANDU-type reactors and high-temperature gas-cooled reactors have been studied in this thesis. Fissile makeup consists of enriched 235U or plutonium from uranium-fueled reactors. Uranium resource requirement for each of the thorium fuel cycles has been calculated and compared with the uranium requirement of the fuel cycles of the corresponding uranium-fueled reference designs. Using thorium in the existing light-water reactors is the easiest way of introducing thorium fuel cycles in this country. The uranium ore requirement over a 30-year reactor lifetime, for the fully-enriched-uranium-thorium fuel cycle is only 17% less than that for the uranium fuel cycle, with uranium and plutonium recycle. Among all the fuel cycles studied in this thesis, the 93.5% 235U-Th CANDU fuel cycle needs the least uranium resources. Self sustaining thorium breeding is also a possibility, with only small changes to the thorium-fueled CANDU reactor operating conditions. Therefore, this fuel cycle could be a logical choice if there were a serious delay in the commercialization of liquid-metal fast breeder reactor

153

Cracked fuel mechanics  

International Nuclear Information System (INIS)

Fuel pellets undergo thermally induced cracking during normal reactor operation. Some fuel performance codes have included models that address the effects of fuel cracking on fuel rod thermal and mechanical behavior. However, models that rely too heavily on continuum mechanics formulations (annular gaps and solid cylindrical pellets) characteristically do not adequately predict cladding axial elongations. Calculations of bamboo ridging generally require many assumptions concerning fuel geometry, and some of the methods used are too complex and expensive to employ on a routine basis. Some of these difficulties originate from a lack of definition of suitable parameters which describe the cracked fuel medium. The methodology is being improved by models that describe cracked fuel behavior utilizing parameters with stronger physical foundations instead of classical continuum formulations. This paper presents a modelling concept and a set of measurable parameters that have been shown to improve the prediction of the mechanical behavior of cracked fuel/cladding systems without added computational expense. The transition from classical annular gap/cylindrical pellet models to modified bulk properties and further to local behavior for cracked fuel systems is discussed. The results of laboratory experiments to verify these modelling parameters are shown. Data are also presented from laboratory experiments on unirradiated and irradiated rods which show that fuel rod mechanical response depends on fuel fragment size. The impact of these data on cracked fuel behavior and failure modelling is also discussed. (author)

154

Fuel assembly identification  

International Nuclear Information System (INIS)

Requirements are presented for the unique identification of fuel assemblies utilized in nuclear power plants. Although developed primarily for commercial light-water reactor fuel, this standard may be used for any reactor containing discrete fuel assemblies. It is a revision of N18.3-1972

155

CANDU fuel performance  

International Nuclear Information System (INIS)

The paper presents a review of CANDU fuel performance including a 28-element bundle for Pickering reactors, a 37-element bundle for the Bruce and Darlington reactors, and a 37-element bundle for the CANDU-6 reactors. Special emphasis is given to the analysis of fuel defect formation and propagation and definition of fuel element operating thresholds for normal operation and accident conditions. (author)

156

World Hydrogen Fueling Stations  

Science.gov (United States)

This document provides information on hydrogen fueling stations in the United States and other countries including Canada, Australia, Germany and Japan. Individual fueling stations are profiled, including the fuel type provided, when it was opened, how the hydrogen is produced and other details. Small photographs of each station are also included. This document may be downloaded in PDF file format.

2012-09-06

157

DUPIC fuel compatibility assessment  

International Nuclear Information System (INIS)

In this report, analysis results for the CANDU 6 reactor with DUPIC fuel have been described. Various problems are assessed against the standard natural uranium fuel core such as fuel fabrication, fuel rod and bundle design, in-core loading, in-core fuel management, spent fuel treatment and overall fuel cycle. Some of the results are related to the license and demonstration. From the up to date results, it is known that the DUPIC fuel fabrication is technically feasible and the anticipated in-core problems can be resolved by current technique. Also, the benefit is expected in power distribution and fuel burnup. However, because the CANDU 6 reactor is originally designed for natural uranium fuel, some demerits are found in some field such as radiation damage of the reactor structural material, operational margin decrease by composition heterogeneity, increase in fission product release of accident condition, deterioration of fuel pellet material property. These problems should be resolved technically including design improvement of DUPIC fuel and CANDU 6 reactor. Furthermore, experimental verifications should be performed for reactor physics and thermal hydraulics. This report describes the compatibility with the CANDU 6 reactor, and it should be noted that detail and wide work should be performed for more reliable results

158

ALTERNATIVE FUELS RESEARCH STRATEGY  

Science.gov (United States)

The purpose of this document was to lay a foundation for developing the scientific information needed to compare the benefits and risks of various motor vehicle fuels, especially alternative and reformulated fuels in relation to conventional gasoline and diesel fuels. Among the f...

159

Westinghouse fuel pellet evolution  

International Nuclear Information System (INIS)

Recognizing fuel reliability, fuel cycle cost and security of supply as key customer expectations, Westinghouse has developed a comprehensive strategy for fuel pellet evolution. It encompasses state of art flawless manufacturing and a superior irradiation behavior as well as standardization across manufacturing facilities

160

Plutonium fuel program  

International Nuclear Information System (INIS)

A review is presented of the development of the (UPu)C sphere-pac fuel project during 1978. In particular, the problems encountered in obtaining good fuel quality in the fabrication process and their solution is discussed. The development of a fabrication pilot plant is considered, and the post-irradiation examination of fuel pins is presented. (Auth.)

 
 
 
 
161

Reactor fuel assemblies  

International Nuclear Information System (INIS)

A description is given of an improved spacer grid for a nuclear fuel assembly comprising fuel rods in a matrix wherein each rod is adapted to be enclosed by a spacer ''cell'' for positioning thereof relative to adjacent rods in the fuel assembly. 7 claims, 12 drawing figures

162

Fuel Cell Technologies Program  

Science.gov (United States)

This document from the U.S. Department of Energy provides an introduction to fuel cell technology. The material outlines how they work, and why they may be chosen as a fuel source. Different types of fuel cells, their applications, advantages and disadvantages are outlined. This document may be downloaded in PDF file format.

2012-01-03

163

Clickable Fuel Cell Car  

Science.gov (United States)

In this interactive, students can investigate a typical hydrogen fuel cell prototype car from its fuel cell stacks to its ultracapacitor, a kind of supplementary power source. The limited-production vehicle seen in this feature is a Honda 2005 FCX, which is typical of the kinds of hydrogen fuel cell cars that some major automakers are now researching and developing.

Tyson, Peter; Novasciencenow

164

Direct Methanol Fuel Cell  

Science.gov (United States)

This sheet provides information about direct methanol fuel cells. Details on the chemistry involved are included in graphic form along with several notes on these fuel cells. This material would be most appropriate for upper level students who already have a basic understanding of fuel cell technology and chemistry. This document may be downloaded in PDF file format.

2012-08-08

165

Molten Carbonate Fuel Cell  

Science.gov (United States)

This page is an introduction to the Molten Carbonate fuel cell. It uses flash animation to explain in greater detail what the Molten Carbonate fuel cell consists of and how it works. The website has an introductory animation which is followed by more in depth description of the molten carbonate fuel cell works.

2010-09-08

166

Solid Oxide Fuel Cell  

Science.gov (United States)

This page is an introduction to the Solid Oxide fuel cell. It uses flash software to explain in greater detail what the Solid Oxide fuel cell consists of and how it works. The website has an introductory animation which is followed by more in depth description of the solid oxide fuel cell.

2012-09-12

167

PWR fuel thermomechanics  

International Nuclear Information System (INIS)

Fuel thermo-mechanics means the studies of mechanical and thermal effects, and more generally, the studies of the behavior of the fuel assembly under stresses including thermal and mechanical loads, hydraulic effects and phenomena induced by materials irradiation. This paper describes the studies dealing with the fuel assembly behavior, first in normal operating conditions, and then in accidental conditions. 43 refs

168

Fuel and fuel cycles with high burnup for WWER reactors  

International Nuclear Information System (INIS)

The paper discusses the status and trends in development of nuclear fuel and fuel cycles for WWER reactors. Parameters and main stages of implementation of new fuel cycles will be presented. At present, these new fuel cycles are offered to NPPs. Development of new fuel and fuel cycles based on the following principles: profiling fuel enrichment in a cross section of fuel assemblies; increase of average fuel enrichment in fuel assemblies; use of refuelling schemes with lower neutron leakage ('in-in-out'); use of integrated fuel gadolinium-based burnable absorber (for a five-year fuel cycle); increase of fuel burnup in fuel assemblies; improving the neutron balance by using structural materials with low neutron absorption; use of zirconium alloy claddings which are highly resistant to irradiation and corrosion. The paper also presents the results of fuel operation. (author)

169

Nuclear fuel assembly  

International Nuclear Information System (INIS)

A nuclear fuel assembly includes and upper yoke, a base, an elongated, outer flow channel disposed substantially along the entire length of the fuel assembly and an elongated, internal, central water cross, formed by four, elongated metal angles, that divides the nuclear fuel assembly into four, separate, elongated fuel sections and that provides a centrally disposed path for the flow of subcooled neutron moderator along the length of the fuel assembly. A separate fuel bundle is located in each of the four fuel sections and includes an upper tie plate, a lower tie plate and a plurality of elongated fuel rods disposed therebetween. Preferably, each upper tie plate is formed from a plurality of interconnected thin metal bars and includes an elongated, axially extending pin that is received by the upper yoke of the fuel assembly for restraining lateral motion of the fuel bundle while permitting axial movement of the fuel bundle with respect to the outer flow channel. The outer flow channel is fixedly secured at its opposite longitudinal ends to the upper yoke and to the base to permit the fuel assembly to be lifted and handled in a vertical position without placing lifting loads or stresses on the fuel rods. The yoke, removably attached at the upper end of the fuel assembly to four structural ribs secured to the inner walls of the outer flow channel, includes, as integrally formed components, a lifting bail or handle, laterally extending bumpers, a mounting post for a spxtending bumpers, a mounting post for a spring assembly, four elongated apertures for receiving with a slip fit the axially extending pins mounted on the upper tie plates and slots for receiving the structural ribs secured to the outer flow channel. Locking pins securely attach the yoke to the structural ribs enabling the fuel assembly to be lifted as an entity

170

Neutronic fuel element fabrication  

Science.gov (United States)

This disclosure describes a method for metallurgically bonding a complete leak-tight enclosure to a matrix-type fuel element penetrated longitudinally by a multiplicity of coolant channels. Coolant tubes containing solid filler pins are disposed in the coolant channels. A leak-tight metal enclosure is then formed about the entire assembly of fuel matrix, coolant tubes and pins. The completely enclosed and sealed assembly is exposed to a high temperature and pressure gas environment to effect a metallurgical bond between all contacting surfaces therein. The ends of the assembly are then machined away to expose the pin ends which are chemically leached from the coolant tubes to leave the coolant tubes with internal coolant passageways. The invention described herein was made in the course of, or under, a contract with the U.S. Atomic Energy Commission. It relates generally to fuel elements for neutronic reactors and more particularly to a method for providing a leak-tight metal enclosure for a high-performance matrix-type fuel element penetrated longitudinally by a multiplicity of coolant tubes. The planned utilization of nuclear energy in high-performance, compact-propulsion and mobile power-generation systems has necessitated the development of fuel elements capable of operating at high power densities. High power densities in turn require fuel elements having high thermal conductivities and good fuel retention capabilities at high temperatures. A metal clad fuel element containing a ceramic phase of fuel intimately mixed with and bonded to a continuous refractory metal matrix has been found to satisfy the above requirements. Metal coolant tubes penetrate the matrix to afford internal cooling to the fuel element while providing positive fuel retention and containment of fission products generated within the fuel matrix. Metal header plates are bonded to the coolant tubes at each end of the fuel element and a metal cladding or can completes the fuel-matrix enclosure by encompassing the sides of the fuel element between the header plates.

Korton, George (Cincinnati, OH)

2004-02-24

171

Chemistry in fuel rods containing oxide fuels  

International Nuclear Information System (INIS)

The oxides of uranium and plutonium, which are chemically (and physically) rather stable compounds, are used as nuclear fuels. The internal fuel rod chemistry is mainly determined by the behaviour of the fission products, the changes in the overall oxygen/metal atomic ratio in course of the burnup, and by migration effects caused by high temperature gradients. Also chemical (and mechanical) interactions between the fuel pellets and the cladding (Zircaloy or steel) must be considered. In case of fuel rod defection, the high stability of the fuel against the ingress of collant is highly important. In judging the resulting change of the stoichiometry, which influences the oxide properties, also oxidative reactions with the cladding material must be taken into account. The thin and sometimes patchy oxide layers inside the cladding tube, and other layers which may also contain Cs and U do not impair the fuel rod performance. More important are I (and its compounds) and/or Cd, which may cause stress corrosion cracking. Tensile stress can occur in the cladding wall after rapid increase of the power (f.i. locally after movement of control rods) due to differential thermal expansion of pellets and cladding. Cs plays a similar role in the observed grain boundary corrosion of austenitic steel cladding tubes of fast breeder fuel. (orig./HP)

172

77 FR 13009 - Regulation of Fuels and Fuel Additives: Identification of Additional Qualifying Renewable Fuel...  

Science.gov (United States)

...80 [EPA-HQ-OAR-2011-0542; FRL-9642-3] RIN 2060-AR07 Regulation of Fuels and Fuel Additives: Identification of Additional Qualifying Renewable Fuel Pathways Under the Renewable Fuel Standard Program AGENCY: Environmental...

2012-03-05

173

Nuclear fuel lease accounting  

International Nuclear Information System (INIS)

The subject of nuclear fuel lease accounting is a controversial one that has received much attention over the years. This has occurred during a period when increasing numbers of utilities, seeking alternatives to traditional financing methods, have turned to leasing their nuclear fuel inventories. The purpose of this paper is to examine the current accounting treatment of nuclear fuel leases as prescribed by the Financial Accounting Standards Board (FASB) and the Federal Energy Regulatory Commission's (FERC's) Uniform System of Accounts. Cost accounting for leased nuclear fuel during the fuel cycle is also discussed

174

Plutonium fuel program  

International Nuclear Information System (INIS)

The work of the project Fuel Development in 1976 was marked by three important developments. Firstly, the reproduceability of the process to produce sphere pac carbide fuel by a gelation process was established. Secondly, in the post irradiation examination of the fuel pins from the BR-2 reactor, the fuel reached approximately 5.5% FIMA without failure. Thirdly, outside interest in sphere pac material became more apparent. These developments are discussed, and plans to construct a fuel pilot plant to go into operation in the 1980's are revealed. (Auth.)

175

Finnish Nuclear Fuel Cycle  

International Nuclear Information System (INIS)

Current nuclear fuel cycle used in Finland is open once-through fuel cycle in which spent fuel is disposed directly without any reprocessing. However, future nuclear energy systems, which are now under development, are planned to utilize mainly partly or fully closed fuel cycles where spent nuclear fuel is reprocessed and reusable compounds are recycled back to fuel fabrication process. The objective of this report is to evaluate development of Finland's nuclear capacity and nuclear fuel cycle in coming years, and also evaluate impact of spent fuel reprocessing, recycling and introducing of fast reactors on uranium consumption, amount of spent nuclear fuel and economy of nuclear energy. In addition uranium production in Talvivaara and Sokli mines was evaluated. Finland's nuclear capacity for coming years was first evaluated based on current situation and some assumptions. Then, based on preceding capacity, two advanced nuclear fuel cycle scenarios were compared to today's once-through fuel cycle. Mass flows between different fuel cycle processes were calculated with IAEA's Nuclear Fuel Cycle Simulation System. According to the results, uranium need for recent open nuclear fuel cycle was about 100 thousand tons by 2100. With reprocessing and plutonium recycling uranium need was dropped in 75 thousand tons by 2100. Replacing half of the nuclear capacity with fast reactors in 2074 and 2080, uranium need reduced further in 66 thousand tons by 2100. Accumulated amount of ssand tons by 2100. Accumulated amount of spent nuclear fuel was with open nuclear fuel cycle about 11900 tons by 2100 and with fast reactors about 11200 tons by 2100. Uranium production from Talvivaara and Sokli were evaluated to be sufficient to cover Finland's uranium need up to year 2070 with open nuclear cycle and with advanced fuel cycles up to 2089 and 2106. Fuel cycle costs increased with reprocessing and fuel recycling about 50-67 % compared to open fuel cycle. However, investment and operation and maintenance costs were very similar between different scenarios, so difference between total costs stayed relatively low. (orig.)

176

Nuclear reactor fuel element  

International Nuclear Information System (INIS)

The invention concerns fuel elemnts, where the guide tubes for the control rods are made of zirconium alloys (e.g. Zircaloy), while the spacing grid, the fuel element top and the fuel element bottom consist of steel. In order to connect these different materials together reliably, it is proposed to provide envelopes of material which is the same as that of the fuel element parts, which are metallurgically connected with parts made of the same material, while they are secured to other parts of the fuel elements by positive mechanical locking. The subclaims explain preferred constructional details by means of 13 drawings. (UWI) 891 HP/UWI 892 MB

177

Fuel cycle cost projections  

International Nuclear Information System (INIS)

This report estimates current and future costs associated with the light water reactor nuclear fuel cycle for both once-through and thermal recycle cases. Using a range of future nuclear power generating scenarios, process flows are developed for each segment of the nuclear fuel cycle. Capital and operating costs are estimated and are combined with the process flows to generate unit cost projections for each fuel cycle segment. The unit costs and process flows are combined in the NUCOST program to estimate fuel cycle power costs through the year 2020. The unit costs are also used to estimate the fuel costs of an individual model PWR and BWR

178

Alternative aviation turbine fuels  

Science.gov (United States)

The efficient utilization of fossil fuels by future jet aircraft may necessitate the broadening of current aviation turbine fuel specifications. The most significant changes in specifications would be an increased aromatics content and a higher final boiling point in order to minimize refinery energy consumption and costs. These changes would increase the freezing point and might lower the thermal stability of the fuel and could cause increased pollutant emissions, increased smoke and carbon formation, increased combustor liner temperatures, and poorer ignition characteristics. This paper discusses the effects that broadened specification fuels may have on present-day jet aircraft and engine components and the technology required to use fuels with broadened specifications.

Grobman, J.

1977-01-01

179

Fuel assembly cleaning device  

International Nuclear Information System (INIS)

Purpose: To enable efficient and sufficient cleaning of a fuel assembly even in corners without disassembling the assembly and to effectively remove crud. Constitution: Cleaning water mixed with abrasive is injected into a fuel assembly contained within a cleaning device body to remove crud adhering to the fuel assembly. Since a coolant passage from the opening of the bottom surface is of the fuel assembly to the opening of the top surface is utilized as the cleaning water passage at this, the crud can be removed by the abrasive in the water stream even from narrow gaps of the fuel assembly. (Aizawa, K.)

180

Cornell Fuel Cell Institute  

Science.gov (United States)

The Fuel Cell Institute at Cornell University takes "An Advanced Materials Approach to Fuel Cell Technologies." Materials experts at the Institute are examining ways to improve the efficiency of the main components of a low temperature (fuel cell and adapt reformer catalysts for low temperature operation. The website reviews some of the basics on fuel cells and identifies the remaining research challenges, including questions regarding the materials used in the main components of a fuel cell, such as the anode, the cathode, membrane assembly and, the reformer. These components and their research approach are described further, along with pictures and diagrams to illustrate the processes. Recent publications are available to download.

 
 
 
 
181

Fuel Cells Presentation  

Science.gov (United States)

This presentation from Thomas G. Benjamin and J. David Carter of Argonne National Laboratory introduces the topic of fuel cells. The presentation examines the history and basic operation of fuel cells, types of fuel cells, PEM fuel cells, hydrogen storage and more. The presentation includes fifty slides, many of which include graphics to support the text. This presentation would be a good general starting point for a casual learner curious about fuel cells, or could be used to support energy curriculum. This document may be downloaded in Microsoft PowerPoint file format.

Benjamin, Thomas G.; Carter, J. D.

2012-07-25

182

Fuel-coolant interactions  

International Nuclear Information System (INIS)

In a hypothetical fault sequence important effects of fuel-coolant interactions include voiding and dispersion of core debris as well as the pressure damage usually discussed. The development of the fuel-coolant interaction probably depends on any pre-mixing Weber break-up that may occur, and is therefore a function of the way the fuel and coolant come together. Four contact modes are identified: jetting, shock tube, drops and static, and Culham's experiments have been mainly concerned with simulating the falling drop mode by using molten tin in water. It was observed that the fuel-coolant interaction is a short series of violent coolant oscillations centred at a localized position on the drop, generating a spray of submillimeter sized debris. The interaction started spontaneously at a specific time after the drop first contacted the water. There was a definite limited fuel-coolant interaction zone on a plot of initial coolant temperature versus initial fuel temperature outside which interactions never occurred. The interaction time was a function of the initial temperatures. Theoretical scaling formulae are given which describe the fuel-coolant interaction zone and dwell time. Bounds of fuel and coolant temperature below which fuel-coolant interactions do not occur are explained by freezing. Upper bounds of fuel and coolant temperatures above which there were no fuel-coolant interactions are interpreted in terms of heat transfer through vapour films of various thicknesses. (auth.)

183

AFIP-6 Irradiation Summary Report  

Energy Technology Data Exchange (ETDEWEB)

The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-6 was designed to evaluate the performance of monolithic uranium-molybdenum (U-Mo) fuels at a length prototypic to that of the ATR fuel plates (45 inches in length). The AFIP-6 test was the first test with plates in a swaged condition with longer fuel zones of approximately 22.5 inches in length1,2. The following report summarizes the life of the AFIP-6 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

Danielle M Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

2011-09-01

184

AFIP-4 Irradiation Summary Report  

Energy Technology Data Exchange (ETDEWEB)

The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-4 was designed to evaluate the performance of monolithic uranium-molybdenum (U-Mo) fuels at a scale prototypic of research reactor fuel plates. The AFIP-4 test further examine the fuel/clad interface and its behavior under extreme conditions. After irradiation, fission gas retention measurements will be performed during post irradiation (PIE)1,2. The following report summarizes the life of the AFIP-4 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

Danielle M Perez; Misti A Lillo; Gray S. Chang; Glenn A Roth; Nicolas Woolstenhulme; Daniel M Wachs

2012-01-01

185

AFIP-4 Irradiation Summary Report  

Energy Technology Data Exchange (ETDEWEB)

The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-4 was designed to evaluate the performance of monolithic uranium-molybdenum (U-Mo) fuels at a scale prototypic of research reactor fuel plates. The AFIP-4 test further examine the fuel/clad interface and its behavior under extreme conditions. After irradiation, fission gas retention measurements will be performed during post irradiation (PIE). The following report summarizes the life of the AFIP-4 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

Danielle M Perez; Misti A Lillo; Gray S. Chang; Glenn A Roth; Nicolas Woolstenhulme; Daniel M Wachs

2011-09-01

186

CANDU fuel cycle flexibility  

International Nuclear Information System (INIS)

This paper examines some CANDU fuel cycles that are currently of interest, namely: slightly enriched uranium (SEU), CANDU/PWR tandem cycle, DUPIC (Direct Use of Spent PWR Fuel in CANDU), actinide burning and plutonium destruction, thorium fuel cycles. The use of SEU would lower fuel cycle costs by about 30%. The use of enrichment in CANDU also offers greater flexibility in fuel bundle design. One example is the Low Void Reactivity Fuel (LVRF) bundle, in which the use of enrichment and neutron absorber materials allows any value of void reactivity and discharge burnup to be designed. This has the potential for increasing the degree of passive safety, as well as reducing capital costs. The CANFLEX bundle, with 43 elements and two pin sizes, is being developed as the optimum carrier of enriched fuels in CANDU

187

Recycling of fuel  

International Nuclear Information System (INIS)

The different properties of plutonium affect the safety characteristics of thermal and fast reactors in differing ways. There is a change in isotopic composition of plutonium as recycle proceeds. The chapter describes this and gives data on the build-up of the higher actinides, americium and curium. Attention is drawn to the problems of fabricating and handling plutonium-enriched fuel for use in thermal reactors. As an example, a plant for refabricating mixed uranium oxide-plutonium oxide LWR fuels is described. Mention is made of the problems associated with the transport of plutonium and the impact of the special requirements of plutonium handling on fuel costs. The main difference between plutonium-enriched thermal reactor fuel and plutonium fast reactor fuel is shown to lie in the concentration of plutonium in the fuel and in the complexity of the fuel assemblies

188

Nuclear fuel assembly  

International Nuclear Information System (INIS)

Purpose: To greatly reduce the possibility of fuel can failures thereby increasing the working life of a fuel assembly. Constitution: A plurality of fuel pins each having a spiral wire wound around at a predetermined pitch with both ends of the wire being secured to the upper and the lower portions thereof are disposed to a hexagonal tube at a predetermined direction and at a certain pitch. In this case, the positions for setting the spiral wires to the fuel pin are dispersed at random within a range of ± 30 deg C to the circumferential direction of the fuel pin. This enables to axially disperse the stresses exerted upon swelling expansion to the fuel pin thereby greatly reducing the possibility of fuel can failure as compared with the usual case. (Takahashi, M.)

189

Inspection system for fuels  

International Nuclear Information System (INIS)

A typical embodiment of the invention combines a novel cellular end fitting for a nuclear reactor fuel assembly with a new design for a fuel rod end cap and radiation sensing device probe to provide a means for swiftly and accurately distinguishing sound fuel rods from those rods that have developed leaks. For example, a somewhat thinner than usual fuel rod end cap is accessible through the open cellular structure of the end fitting to permit a hollow metal probe to contact the fuel rod end cap. This direct contact excludes most of the water, metal and other shielding materials from the volume between the interior of the fuel and the radiation detector, thereby improving the quality of the fuel rod examination. A bridge and trolley structure for accurately positioning the probe also is described. (Auth.)

190

Fuel element services  

International Nuclear Information System (INIS)

Refuelling outages comprise a number of maintenance tasks scheduled long in advance to assure a reliable operation throughout the next cycle and, in the long run, a safer and more efficient plant. Most of these tasks are routine service of mechanical and electrical system and likewise fuel an be considered a critical component as to handling, inspection, cleaning and repair. ENUSA-ENWESA AIE has been working in this area since 1995 growing from fuel repair to a more integrated service that includes new and spent fuel handling, inserts, failed fuel rod detection systems, ultrasonic fuel cleaning, fuel repair and a comprehensive array of inspection and tests related to the reliability of the mechanical components in the fuel assembly, all this, performed in compliance with quality, safety, health physics and any other nuclear standard. (Author)

191

Nuclear fuel vibrocompacting  

International Nuclear Information System (INIS)

Prospects of using vibrocompacting in production of fuel elements with mixed oxide fuel are discussed. The role of homogeneity of granulometric composition and form compacted powder particle is considered. Irradiation of a large number of vibrocompacted fuel elements in the BOR-60 reactor has not shown changes in their performances. Technology of fuel vibrocompacting is concluded to be used most likely in production of fuel elements with regenerated fuel for fast breeder reacotors. The described technology complies with reguirements of rational, reliable and remote - controlled production. Industrial use of the considered method depends mainly on the possibility of preparing well compacted powder of homogeneous mixed oxide fuel with stable reproducible characteristics. Special attention should be paid to assurance of high density and constancy of dimensions for certain fractions of spherical particles

192

Fuel Cells 2000  

Science.gov (United States)

Fuel Cells 2000, an organization dedicated to informing the public about fuel cells, offers this website with an interactive map listing companies and research organizations connected with the U.S. fuel cell industry. A second map shows U.S. Fuel Cell Installations and Vehicle Demonstrations. Links to the organizations' websites make this an easy-to-use resource for finding out more about fuel cells and looking up local demonstrations. Visitors can also download a full directory of nearly 1000 fuel-cell related companies and organizations and a chart showing fuel cell installations worldwide. (Unfortunately, many of the other links on this website were not working at the time of this writing.)

193

Fuel safety research 1999  

Energy Technology Data Exchange (ETDEWEB)

In April 1999, the Fuel Safety Research Laboratory was newly established as a result of reorganization of the Nuclear Safety Research Center, JAERI. The laboratory was organized by combining three laboratories, the Reactivity Accident Laboratory, the Fuel Reliability Laboratory, and a part of the Sever Accident Research Laboratory. Consequently, the Fuel Safety Research Laboratory is now in charge of all the fuel safety research in JAERI. Various types of experimental and analytical researches are conducted in the laboratory by using the unique facilities such as the Nuclear Safety Research Reactor (NSRR), the Japan Material Testing Reactor (JMTR), the Japan Research Reactor 3 (JRR-3) and hot cells in JAERI. The laboratory consists of five research groups corresponding to each research fields. They are; (a) Research group of fuel behavior under the reactivity initiated accident conditions (RIA group). (b) Research group of fuel behavior under the loss-of-coolant accident conditions (LOCA group). (c) Research group of fuel behavior under the normal operation conditions (JMTR/BOCA group). (d) Research group of fuel behavior analysis (FEMAXI group). (e) Research group of FP release/transport behavior from irradiated fuel (VEGA group). This report summarizes the outline of research activities and major outcomes of the research executed in 1999 in the Fuel Safety Research Laboratory. (author)

Uetsuka, Hiroshi (ed.) [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

2000-07-01

194

Fuel cell market applications  

Energy Technology Data Exchange (ETDEWEB)

This is a review of the US (and international) fuel cell development for the stationary power generation market. Besides DOE, GRI, and EPRI sponsorship, the US fuel cell program has over 40% cost-sharing from the private sector. Support is provided by user groups with over 75 utility and other end-user members. Objectives are to develop and demonstrate cost-effective fuel cell power generation which can initially be commercialized into various market applications using natural gas fuel by the year 2000. Types of fuel cells being developed include PAFC (phosphoric acid), MCFC (molten carbonate), and SOFC (solid oxide); status of each is reported. Potential international applications are reviewed also. Fuel cells are viewed as a force in dispersed power generation, distributed power, cogeneration, and deregulated industry. Specific fuel cell attributes are discussed: Fuel cells promise to be one of the most reliable power sources; they are now being used in critical uninterruptible power systems. They need hydrogen which can be generated internally from natural gas, coal gas, methanol landfill gas, or other fuels containing hydrocarbons. Finally, fuel cell development and market applications in Japan are reviewed briefly.

Williams, M.C.

1995-12-31

195

Fuel safety research 1999  

International Nuclear Information System (INIS)

In April 1999, the Fuel Safety Research Laboratory was newly established as a result of reorganization of the Nuclear Safety Research Center, JAERI. The laboratory was organized by combining three laboratories, the Reactivity Accident Laboratory, the Fuel Reliability Laboratory, and a part of the Sever Accident Research Laboratory. Consequently, the Fuel Safety Research Laboratory is now in charge of all the fuel safety research in JAERI. Various types of experimental and analytical researches are conducted in the laboratory by using the unique facilities such as the Nuclear Safety Research Reactor (NSRR), the Japan Material Testing Reactor (JMTR), the Japan Research Reactor 3 (JRR-3) and hot cells in JAERI. The laboratory consists of five research groups corresponding to each research fields. They are; (a) Research group of fuel behavior under the reactivity initiated accident conditions (RIA group). (b) Research group of fuel behavior under the loss-of-coolant accident conditions (LOCA group). (c) Research group of fuel behavior under the normal operation conditions (JMTR/BOCA group). (d) Research group of fuel behavior analysis (FEMAXI group). (e) Research group of FP release/transport behavior from irradiated fuel (VEGA group). This report summarizes the outline of research activities and major outcomes of the research executed in 1999 in the Fuel Safety Research Laboratory. (author)

196

Fuel related risks; Braenslerisker  

Energy Technology Data Exchange (ETDEWEB)

The project, within which this work report was prepared, aimed to complement the Vaermeforsk publication 'Handbook of fuels' on fuel related risks and measures to reduce the risks. The fuels examined in this project where the fuels included in the first version of the handbook from 2005 plus four additional fuels that will be included in the second and next edition of the handbook. Following fuels were included: woodfuels (sawdust, wood chips, powder, briquettes), slash, recycled wood, salix, bark, hardwood, stumps, straw, reed canary grass, hemp, cereal, cereal waste, olive waste, cocoa beans, citrus waste, shea, sludge, forest industrial sludge, manure, Paper Wood Plastic, tyre, leather waste, cardboard rejects, meat and bone meal, liquid animal and vegetable wastes, tall oil pitch, peat, residues from food industry, biomal (including slaughterhouse waste) and lignin. The report includes two main chapters; a general risk chapter and a chapter of fuel specific risks. The first one deals with the general concept of risk, it highlights laws and rules relevant for risk management and it discuss general risks that are related to the different steps of fuel handling, i.e. unloading, storing, processing the fuel, transportation within the facility, combustion and handling of ashes. The information that was used to produce this chapter was gathered through a literature review, site visits, and the project group's experience from risk management. The other main chapter deals with fuel-specific risks and the measures to reduce the risks for the steps of unloading, storing, processing the fuel, internal transportation, combustion and handling of the ashes. Risks and measures were considered for all the biofuels included in the second version in the handbook of fuels. Information about the risks and risk management was gathered through interviews with people working with different kinds of fuels in electricity and heat plants in Sweden. The information from the interviews was supplemented with examples from the literature

Englund, Jessica; Sernhed, Kerstin; Nystroem, Olle; Graveus, Frank (Grontmij AB, (Sweden))

2012-02-15

197

Fuel cells are coming  

Energy Technology Data Exchange (ETDEWEB)

Major investments are being made around the world to develop Proton Exchange Membrane Fuel Cell (PEMFC) power plants for the automotive application. To reach a broad commercial market, such vehicles must be capable of operating on liquid fuel. To date, liquid-fueled Fuel Cell transit buses sponsored by the Federal Transit Administration (FTA) have been true hybrids with a traction battery providing surge power and a means to recapture kinetic energy from the bus through regenerative braking. Georgetown University (GU) has proposed to the FTA to build a total of eight Fuel Cell powered transit buses to place vehicles into the hands of transit agencies and provide meaningful test information for future developments. Included in this program is the introduction of non-hybrid vehicles incorporating 200 kw Fuel Cell power plants. The first GU 40-foot Fuel Cell transit bus employs a 100 kW phosphoric Acid Fuel Cell (P AFC) developed by International Fuel Cells, a division of United Technologies Corporation. Since the introduction of this vehicle at the 1998 APTA Bus Conference, this bus has undergone a significant test program to verify the performance and promise of the Fuel Cell technology. Georgetown has recently completed integration of a second 40-foot Fuel Cell bus which uses a 100 kW PEMFC power plant developed by XCELLSiS, a joint venture between DaimlerChrysler, Ballard, and Ford Motor Company. This paper presents a description and status of the new PEMFC bus and identifies key automotive Fuel Cell technology trends which could greatly facilitate introduction of the Fuel Cell technology to the transit bus application. (author)

Romano, S.; Larkins, J.T. [Georgetown Univ. (United States)

2000-07-01

198

CANDU fuel cycle flexibility  

International Nuclear Information System (INIS)

High neutron economy, on-power refuelling, and a simple bundle design provide a high degree of flexibility that enables CANDU (Canada Deuterium Uranium; registered trademark) reactors to be fuelled with a wide variety of fuel types. Near-term applications include the use of slightly enriched uranium (SEU), and recovered uranium (RU) from reprocessed spent Light Water Reactor (LWR) fuel. Plutonium and other actinides arising from various sources, including spent LWR fuel, can be accommodated, and weapons-origin plutonium could be destroyed by burning in CANDU. In the DUPIC fuel cycle, a dry processing method would convert spent Pressurized Water Reactor (PWR) fuel to CANDU fuel. The thorium cycle remains of strategic interest in CANDU to ensure long-term resource availability, and would be of specific interest to those countries possessing large thorium reserves, but limited uranium resources. (author). 21 refs

199

CANDU fuel cycle flexibility  

International Nuclear Information System (INIS)

High neutron economy, on-power refuelling, and a simple bundle design provide a high degree of flexibility that enable CANDU (CANada Deuterium Uranium; registered trademark) reactors to be fuelled with a wide variety of fuel types. Near-term applications include the use of slightly enriched uranium and recovered uranium from reprocessed spent Light Water Reactor (LWR) fuel. Plutonium and other actinides arising from various sources, including spent LWR fuel, can be accommodated, and weapons-origin plutonium could be destroyed by burning in CANDU. In the DUPIC fuel cycle, a dry processing method would convert spent Pressurized Water Reactor fuel to CANDU fuel. The thorium cycle remains of strategic interest in CANDU to ensure long-term resource availability, and would be of specific interest to those countries possessing large thorium reserves, but limited uranium resources. 21 refs

200

candu fuel bundle fabrication  

International Nuclear Information System (INIS)

This paper describes works on CANDU fuel bundle fabrication in the Fuel Fabrication Development and Testing Section (FFDT) of AECL's Chalk River Laboratories. This work does not cover fuel design, pellet manufacturing, Zircaloy material manufacturing, but cover the joining of appendages to sheath tube, endcap preparation and welding, UO2 loading, end plate preparation and welding, and all inspections required in these steps. Materials used in the fabrication of CANDU fuel bundle are: 1)Ceramic UO2 Pellet 2)Zircaloy -4. Fuel Bundle Structural Material 3) Others (Zinc stearate, Colloidal graphite, Beryllium and Heium). Th fabrication of fuel element consist of three process: 1)pellet loading into the sheats, 2) endcap welding, and 3) the element profiling. Endcap welds is tested by metallography and He leak test. The endcaps of the elements are welded to the end plates to form the 37- element bundle assembly

 
 
 
 
201

Nuclear fuel rod  

International Nuclear Information System (INIS)

Fuel pellets formed by incorporating transuranium elements in metal uranium are disposed above oxide uranium fuel pellets. The transuranium-incorporating metal uranium fuel pellets are formed by mixing at least one of Np-237, Am-241 and Am-243 to the metal uranium not absorbing high energy neutrons by oxygen. For example, in a BWR type reactor, neutron spectrum is hard at the upper portion of the nuclear fuel rod. Accordingly, the transuranium-incorporating metal uranium fuel pellets are charged at the upper portion of the nuclear fuel rod, having high energy neutrons, in other words, having hard neutron spectrum. With such a constitution, transuranium elements such as Np and Am can be annihilated effectively. (I.N.)

202

Fuel rod expert system  

International Nuclear Information System (INIS)

Information is given on the Fuel Rod Expert System (FRES), developed for the WWER-440 power units. The system consists of two partially independent parts (i.e. fuel rod damage probability prediction and fuel rod evaluation), which enable: 1) to optimize the operating flexibility from the point of view of minimization of fuel rod damage probability by pellet-cladding interaction during transients; 2) to evaluate cladding integrity of fuel rods during reactor operation and to predict and partially optimize radiation set-ups during transients; and 3) to obtain probability distribution of the fuel rod damage. The FRES software package was installed at the Dukovany nuclear power station as a part of a standard information system. (author). 7 figs., 6 refs

203

Method of assembling fuels  

International Nuclear Information System (INIS)

Purpose: To decrease the surface damages to the fuel elements upon mounting spacers. Method: After cooling the fuel elements to a super-cooled state in a cooling chamber kept at a low temperature, they are passed through a chamber maintained at an excess humidity state to form a thin ice layer at the surface of the fuel elements. The fuel elements are transferred into a drying chamber where they are passed into the spacer to conduct assembly. Since the fuel elements are urged such that they can withstand the hydrodynamic vibrations during reactor operation, the friction upon insertion between the resilient material disposed to the spacer and the fuel element is decreased and the surface damages to the cladding tube resulted due to the vibrations from both of the members are significantly reduced. (Sekiya, K.)

204

Production of liquid fuels  

International Nuclear Information System (INIS)

The greenhouse gas emissions associated with the production and usage of a number of liquid fuels are reviewed, including petroleum-based transport fuels and synthetic fuels derived from natural gas, coal and shale. Comments are also offered on the role of biomass-derived fuels. The methodology employed is similar to that used by DeLuchi and Sperling (1988), but extended to include the production of hydrocarbon fuels from coal and shale. While most of their conclusions are supported, some differences are noted. Most of the current interest in modifying the usage and formulation of transport fuels, stems from the benefits claimed to be achievable for local air quality rather than from reduced greenhouse gas emissions. The changes proposed, could add to the greenhouse burden while others may diminish it. 26 refs., 3 tabs., 2 figs

205

Failed fuel degradation  

International Nuclear Information System (INIS)

Failed fuel degradation is the term used to describe the post-defect deterioration of a fuel rod which can occur under continued operation in certain circumstances. Two mechanisms are generally postulated for failed fuel degradation in light water reactors. The first of these attributes degradation susceptibility (axial split formation) to the inherently low fracture toughness of the zircaloy cladding exacerbated by hydrogen embrittlement. The second mechanism attributes the degradation to the reduced relative corrosion resistance of the zirconium liner present in barrier fuel. This leads to a greater fuel rod internal inventory of embrittling hydrogen in conjunction with increased cladding stresses caused by closure of the pellet-cladding gap due to liner corrosion. Key observations relating to these mechanisms are reviewed and the development of mitigating actions to address them described. Commercial irradiation experience gained with subsequently improved fuel designs is discussed. (5 figures; 7 references) (UK)

206

Hydrogen - the new fuel  

International Nuclear Information System (INIS)

The energy resources of the planet are discussed. It is pointed out that Hydrogen is one of the most valuable alternatives of classical fuels. The opinion of most of the political and technical authorities from all over the world on this point is cited. They have discussed the possible applications of Hydrogen as fuel for internal combustion engines as well as chemical fuel in the so called 'fuel cells'. It was pointed out that the use of Hydrogen in fuel cells is more prospective alternative for traction purposes, for reserve sources, etc. The most prospective types of fuel cells are considered at the present moment. The methods of Hydrogen production and infrastructure of functioning Hydrogen energetics are also discussed. (authors)

207

Nuclear fuel element  

International Nuclear Information System (INIS)

Purpose: To provide a fuel element for reducing the mechanical interactions between a fuel-cladding tube and the fuel element and for alleviating the limits of the operating conditions of a reactor. Constitution: A fuel element having mainly uranium dioxide consists of a cylindrical outer pellet and cylindrical inner pellet inserted into the outer pellet. The outer pellet contains two or more additives selected from aluminium oxide, beryllium oxide, magnesium oxide, silicon oxide, sodium oxide, phosphorus oxide, calcium oxide and iron oxide, and the inner pellet contains nuclear fuel substance solely or one additive selected from calcium oxide, silicon oxide, aluminium oxide, magnesium oxide, zirconium oxide and iron oxide. The outer pellet of the fuel thus constituted is reduced in mechanical strength and also in the mechanical interactions with the cladding tube, and the plastic fluidity of the entire pellet is prevented by the inner pellet increased in the mechanical strength. (Kamimura, M.)

208

The Tarapur fuel controversy  

International Nuclear Information System (INIS)

As a consequence of India's peaceful nuclear explosion at Pokhran in 1974, the United States started delaying the shipments of enriched uranium fuel supplies in order to pressurise India to sign the NPT treaty which India has refused to do so on account of its discriminatory nature. According to the 1963 agreement, the USA is supposed to supply the enriched uranium fuel for Tarapur Atomic Power Station (TAPS) for its entire life time i.e. up to 1993. With the uncertainty in fuel supplies, the Tarapur reactor units are being run at a low capacity factor to conserve fuel. In case the USA abrogates the treaty, India intends to run TAPS on mixed oxide fuel part of which will come from reprocessing of spent fuel of TAPS. Cost of power production will go up. Other problems, particularly the problem of reactor safety will have to be closely looked into. (M.G.B.)

209

Nuclear fuel accountability experience  

International Nuclear Information System (INIS)

The use of burnup credit for dry storage nuclear fuel casks requires that the reactivity of the fuel assemblies be properly verified. As an operating nuclear utility, Virginia Power Company has extensive experience in the administrative control of fuel assemblies from the time they arrive on-site until the time they are dispositioned for final storage, whether in pool storage, dry cask storage, or off-site shipment. The initial uranium enrichment is verified before the assembly arrives on-site, and analyses determine the burnup and the uranium and plutonium content of the assembly during its operation. Assemblies that may have experienced fuel cladding defects, as indicated by reactor coolant system radionuclide measurements, are examined following the fuel cycle and placed on a restricted list of fuel assemblies which are not to be reused in a reactor

210

Spacers for nuclear fuels  

International Nuclear Information System (INIS)

Purpose: To obtain fuel spacers capable of surely supporting fuel rods under the conditions used in the reactor and easily inserting the fuel rods upon assembling, by forming elastic support members provided to the spacer for supporting fuel rods with bimetal type composite materials. Constitution: In a nuclear fuel spacer in which elastic support members are disposed to a support lattice made of a plurality of band-lile members assembled into a frame, elastic support points on said elastic support members are formed with composite materials of two metal plates overlapped to each other and having different thermal expansion coefficient (bimetal). The composite material preferably comprises in combination, zircalloy material disposed on the side in contact with the fuel rod and Inconel alloy material (or stainless steel) disposed on the other side. (Kawakami, Y.)

211

HTR fuel manufacturing experience  

International Nuclear Information System (INIS)

The development of the HTR line promises the availability of a number of technologies which can be used in many area of energy supply. Special properties of nuclear energy exploitation in high-temperature reactors include economical uranium consumption and lower pollution of the environment. Fuel cycle, design and irradiation performance requirements impose restraints on the fuel elements fabrication processes. Both kernel and coating fabrication processes are flexible enough to adapt to the needs of the various existing and proposed high temperature gas-cooled reactors. Extensive experience has demonstrated that fuel kernels with excellent sphericity and uniformity can be produced by wet chemical processes. Similarly experience has shown that the various multilayer coatings can be produced to fully meet design and specification requirements. In a comprehensive qualification program for fuel elements the low failure fraction of coated fuel particles, optimal matrix behavior and the required fission product retention of integral fuel elements was successfully demonstrated

212

Spiral cooled fuel nozzle  

Science.gov (United States)

A fuel nozzle for delivery of fuel to a gas turbine engine. The fuel nozzle includes an outer nozzle wall and a center body located centrally within the nozzle wall. A gap is defined between an inner wall surface of the nozzle wall and an outer body surface of the center body for providing fuel flow in a longitudinal direction from an inlet end to an outlet end of the fuel nozzle. A turbulating feature is defined on at least one of the central body and the inner wall for causing at least a portion of the fuel flow in the gap to flow transverse to the longitudinal direction. The gap is effective to provide a substantially uniform temperature distribution along the nozzle wall in the circumferential direction.

Fox, Timothy; Schilp, Reinhard

2012-09-25

213

Fuel cell generator with fuel electrodes that control on-cell fuel reformation  

Science.gov (United States)

A fuel cell for a fuel cell generator including a housing including a gas flow path for receiving a fuel from a fuel source and directing the fuel across the fuel cell. The fuel cell includes an elongate member including opposing first and second ends and defining an interior cathode portion and an exterior anode portion. The interior cathode portion includes an electrode in contact with an oxidant flow path. The exterior anode portion includes an electrode in contact with the fuel in the gas flow path. The anode portion includes a catalyst material for effecting fuel reformation along the fuel cell between the opposing ends. A fuel reformation control layer is applied over the catalyst material for reducing a rate of fuel reformation on the fuel cell. The control layer effects a variable reformation rate along the length of the fuel cell.

Ruka, Roswell J. (Pittsburgh, PA); Basel, Richard A. (Pittsburgh, PA); Zhang, Gong (Murrysville, PA)

2011-10-25

214

Nuclear fuel particles  

International Nuclear Information System (INIS)

Coated nuclear fuel particles are made by first pyrolytically depositing low density carbon onto fuel cores and thereafter depositing a fission-product retentive, higher density exterior coating. In the improvement, cores of uranium, thorium or plutonium oxides are coated by co-depositing silicon carbide or zirconium carbide along with the low density pyrocarbon to create a uniform dispersion. Silicon or zirconium is deposited in an amount equal to at least about one atom for each fission anticipated during the fuel lifetime

215

Fuel safety research 2001  

Energy Technology Data Exchange (ETDEWEB)

The Fuel Safety Research Laboratory is in charge of research activity which covers almost research items related to fuel safety of water reactor in JAERI. Various types of experimental and analytical researches are being conducted by using some unique facilities such as the Nuclear Safety Research Reactor (NSRR), the Japan Material Testing Reactor (JMTR), the Japan Research Reactor 3 (JRR-3) and the Reactor Fuel Examination Facility (RFEF) of JAERI. The research to confirm the safety of high burn-up fuel and MOX fuel under accident conditions is the most important item among them. The laboratory consists of following five research groups corresponding to each research fields; Research group of fuel behavior under the reactivity initiated accident conditions (RIA group). Research group of fuel behavior under the loss-of-coolant accident conditions (LOCA group). Research group of fuel behavior under the normal operation conditions (JMTR/BOCA group). Research group of fuel behavior analysis (FEMAXI group). Research group of radionuclides release and transport behavior from irradiated fuel under severe accident conditions (VEGA group). The research conducted in the year 2001 produced many important data and information. They are, for example, the fuel behavior data under BWR power oscillation conditions in the NSRR, the data on failure-bearing capability of hydrided cladding under LOCA conditions and the FP release data at very high temperature in steam which simulate the reactor core condition during severe accidents. This report summarizes the outline of research activities and major outcomes of the research executed in 2001 in the Fuel Safety Research Laboratory. (author)

Uetsuka, Hiroshi (ed.) [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

2002-11-01

216

Fuel components QC reports  

International Nuclear Information System (INIS)

The Fuel Components Operation (FCO) of General Electric's Wilmington Manufacturing Department manufactures nuclear fuel bundle components. The Fuel Components Quality Control (FCQC) Reporting System is the method by which Quality information is captured, processed, and fed back to management and responsible individual contributors. The system recognizes, separates, and addresses the needs of all levels of users. The manner in which Quality information is communicated and utilized to improve yields and reduce manufacturing losses is the key to its success

217

Plutonium fuel program  

International Nuclear Information System (INIS)

The project is concerned with developing an advanced method to produce nuclear reactor fuels. Since 1968 EIR has worked successfully on the production of uranium-plutonium mixed carbide using wet gelation chemistry. An important part of the development is irradiating the fuel in materials test reactors and evaluating its performance. During 1979 the programme continued with principal activities of fuel fabrication development, preparation for irradiation testing, performance evaluation, and modelling and plant engineering. (Auth.)

218

NOVA: Fuel Cells  

Science.gov (United States)

This 14-minute video explores the technology of the hydrogen fuel cell designed for use in automobiles. It delves into the promise of the technology, hurdles (such as building filling stations), and challenges of finding green ways to produce hydrogen. You'll also find an animated tutorial on how fuel cells work, a clickable schematic view of a fuel cell installed in a car, and an a question/answer set featuring an expert in energy conversion devices.

2014-03-30

219

Nuclear fuel elements  

International Nuclear Information System (INIS)

The uneven axial neutron flux distribution in a nuclear reactor core is used by using fuel rod spacers of low neutron absorption in areas of high neutron flux density and fuel rod spacers of low flow resistance to the coolant in areas of low neutral flux density of the core, where this combination of spacers also offers a higher thermal limit of the bundle of fuel elements. (orig.)

220

Nuclear fuel element  

International Nuclear Information System (INIS)

Object: To reduce stress concentration onto a clad pipe due to thermal deformation of nuclear fuel element, particularly, ridging deformation in the neighbourhood of upper and lower ends of pellet, and to prevent rupture of the clad pipe. Structure: In a nuclear fuel element in which the nuclear fuel material is enclosed in a clad pipe, the nuclear fuel material comprises a cylindrical outer shell and a columnar inner shell inserted internally of said outer shell in small spaced relation, and lubricating material such as graphite is arranged in the aforesaid spacing. (Ohara, T.)

 
 
 
 
221

Fuel cells. Pt. 1  

International Nuclear Information System (INIS)

Direct conversion of chemical energy into electricity (without intermediate heat generation) is a long-established method to improve the efficiency of power generation, as well as to reduce polluting emissions from thermal plants. The origins of fuel cells, as well as their operating principles, are dealt with. Then, various types of cells are taken into consideration, on the basis of both their characteristics and the operating principles of electrolytes. Finally, structure and operation of Polymer Electrolyte Membrane Fuel Cells (PEMFC), Alkaline Fuel Cells (AFC) and Phosphoric Acid Fuel Cells (PAFC) are described

222

Fuel processing device  

Science.gov (United States)

An improved fuel processor for fuel cells is provided whereby the startup time of the processor is less than sixty seconds and can be as low as 30 seconds, if not less. A rapid startup time is achieved by either igniting or allowing a small mixture of air and fuel to react over and warm up the catalyst of an autothermal reformer (ATR). The ATR then produces combustible gases to be subsequently oxidized on and simultaneously warm up water-gas shift zone catalysts. After normal operating temperature has been achieved, the proportion of air included with the fuel is greatly diminished.

Ahluwalia, Rajesh K. (Burr Ridge, IL); Ahmed, Shabbir (Naperville, IL); Lee, Sheldon H. D. (Willowbrook, IL)

2011-08-02

223

Fuel assembly reconstitution  

International Nuclear Information System (INIS)

Fuel failures have been happened in Nuclear Power Plants worldwide, without lost of integrity and safety, mainly for the public, environment and power plants workers. The most common causes of these events are corrosion (CRUD), fretting and pellet cladding interaction. These failures are identified by increasing the activity of fission products, verified by chemical analyses of reactor coolant. Through these analyses, during the fourth operation cycle of Angra 2 Nuclear Power Plant, was possible to observe fuel failure indication. This indication was confirmed in the end of the cycle during the unloading of reactor core through leakage tests of fuel assembly, using the equipment called 'In Mast Sipping' and 'Box Sipping'. After confirmed, the fuel assembly reconstitution was scheduled, and happened in April, 2007, where was identified the cause and the fuel rod failure, which was substitute by dummy rods (zircaloy). The cause was fretting by 'debris'. The actions to avoid and prevent fuel assemblies failures are important. The goals of this work are to describe the methodology of fuel assembly reconstitution using the FARE (Fuel Assembly Reconstitution Equipment) system, to describe the results of this task in economic and security factors of the company and show how the fuel assembly failures are identified during operation and during the outage. (author)

224

Hydrogen: Fueling the Future  

International Nuclear Information System (INIS)

y using fuel cells provides a high efficiency, carbon-free power source. Hydrogen serves to blur the line between stationary and mobile power applications, as it can be used as both a transportation fuel and for stationary electricity generation, with the possibility of a distributed generation energy infrastructure. Hydrogen and fuel cell technologies will be presented as possible pollution-free solutions to present and future energy concerns. Recent hydrogen-related research at SLAC in hydrogen production, fuel cell catalysis, and hydrogen storage will be highlighted in this seminar.

225

Fuel exchanging machine  

International Nuclear Information System (INIS)

Purpose: To speed up the fuel exchanging work reliably and safely. Constitution: In a fuel exchanging machine, an extensible mast is attached to a fuel exchanging platform and a fuel suspending device attached with a guide member is mounted to the mast. The member is formed with a guide hole for guiding the handle of a fuel assembly to its suspending position. In this invention, the fuel suspending device is made rotatable around a vertical axis, and at least a pair of non-contact type metal sensors that sense the handle are disposed to the lower surface of the guide member in a point-to-point symmetry with respect to the rotating shaft of the fuel suspending device as the center. In this way, positional displacement for the guide member can easily be amended to shorten the working time and, since collision and contact between the guide member and the handle for the fuel assembly can be avoided, fuel exchanging operation can be effected reliably and safely. (Kawakami, Y.)

226

Fuel channel performance  

International Nuclear Information System (INIS)

This paper summarizes the performance of fuel channels in CANDU reactors. The evolution of the overall fuel channel design and the modifications to individual components are described. The main fuel channel component, the pressure tube, is subject from service conditions, to changes in three principal factors, dimensions, properties and composition, each of which can affect performance or life of the tube. The changes that occur are reviewed briefly. The performance of the channels from the view point of operating problems and replacement experience show the relatively low man-rem expenditure associated with fuel channel replacement. The report concludes with an outline of channel design development

227

Reprocessing RERTR silicide fuels  

Energy Technology Data Exchange (ETDEWEB)

The Reduced Enrichment Research and Test Reactor Program is one element of the United States Government's nonproliferation effort. High-density, low-enrichment, aluminum-clad uranium silicide fuels may be substituted for the highly enriched aluminum-clad alloy fuels now in use. Savannah River Laboratory has performed studies which demonstrate reprocessability of spent RERTR silicide fuels at Savannah River Plant. Results of dissolution and feed preparation tests and solvent extraction processing demonstrations with both unirradiated and irradiated uranium silicide fuels are presented.

Rodrigues, G.C.; Gouge, A.P.

1983-05-01

228

Reprocessing RERTR silicide fuels  

International Nuclear Information System (INIS)

The Reduced Enrichment Research and Test Reactor Program is one element of the United States Government's nonproliferation effort. High-density, low-enrichment, aluminum-clad uranium silicide fuels may be substituted for the highly enriched aluminum-clad alloy fuels now in use. Savannah River Laboratory has performed studies which demonstrate reprocessability of spent RERTR silicide fuels at Savannah River Plant. Results of dissolution and feed preparation tests and solvent extraction processing demonstrations with both unirradiated and irradiated uranium silicide fuels are presented

229

Fuel Cell Demonstration Program  

Energy Technology Data Exchange (ETDEWEB)

In an effort to promote clean energy projects and aid in the commercialization of new fuel cell technologies the Long Island Power Authority (LIPA) initiated a Fuel Cell Demonstration Program in 1999 with six month deployments of Proton Exchange Membrane (PEM) non-commercial Beta model systems at partnering sites throughout Long Island. These projects facilitated significant developments in the technology, providing operating experience that allowed the manufacturer to produce fuel cells that were half the size of the Beta units and suitable for outdoor installations. In 2001, LIPA embarked on a large-scale effort to identify and develop measures that could improve the reliability and performance of future fuel cell technologies for electric utility applications and the concept to establish a fuel cell farm (Farm) of 75 units was developed. By the end of October of 2001, 75 Lorax 2.0 fuel cells had been installed at the West Babylon substation on Long Island, making it the first fuel cell demonstration of its kind and size anywhere in the world at the time. Designed to help LIPA study the feasibility of using fuel cells to operate in parallel with LIPA's electric grid system, the Farm operated 120 fuel cells over its lifetime of over 3 years including 3 generations of Plug Power fuel cells (Lorax 2.0, Lorax 3.0, Lorax 4.5). Of these 120 fuel cells, 20 Lorax 3.0 units operated under this Award from June 2002 to September 2004. In parallel with the operation of the Farm, LIPA recruited government and commercial/industrial customers to demonstrate fuel cells as on-site distributed generation. From December 2002 to February 2005, 17 fuel cells were tested and monitored at various customer sites throughout Long Island. The 37 fuel cells operated under this Award produced a total of 712,635 kWh. As fuel cell technology became more mature, performance improvements included a 1% increase in system efficiency. Including equipment, design, fuel, maintenance, installation, and decommissioning the total project budget was approximately $3.7 million.

Gerald Brun

2006-09-15

230

Transient fuel melting  

International Nuclear Information System (INIS)

The observation of micrographic documents from fuel after a CABRI test leads to postulate a specific mode of transient fuel melting during a rapid nuclear power excursion. When reaching the melt threshold, the bands which are characteristic for the solid state are broken statistically over a macroscopic region. The time of maintaining the fuel at the critical enthalpy level between solid and liquid is too short to lead to a phase separation. A significant life-time (approximately 1 second) of this intermediate ''unsolide'' state would have consequences on the variation of physical properties linked to the phase transition solid/liquid: viscosity, specific volume and (for the irradiated fuel) fission gas release

231

Spent fuel cask  

International Nuclear Information System (INIS)

In a spent fuel cask, buffer members having an earthquake proof performance are disposed at the lower surface of a support structural members. In addition, buffer members having an earthquake proof performance are disposed between a basket support and a cask main body. Further, a spring support mechanism is disposed in the inside of the basket. Alternatively, a damper having viscous resistance is disposed. Since the acceleration exerted on spent fuels in the main body of the spent fuel cask and spent fuels in the cask is reduced during earthquakes or during transportation, the collision of the spent fuels and the basket is prevented, or even if they should collide, the colliding force is moderated. Upon occurrence of earthquakes or during transportation of spent fuel cask and operation of a crane for the spent fuel cask, the collision of the spent fuels contained in the spent fuel cask and the basket can be prevented, or the colliding force by the collision can be moderated, to improve the integrity. (N.H.)

232

A perfect fuel supplier  

International Nuclear Information System (INIS)

WWER fuel market is dominated by the Russian fuel vendor JSC TVEL. There have been attempts to open up the market also for other suppliers, such as BNFL/Westinghouse for Finland, Czech Republic, and Ukraine. However, at the moment it seems that JSC TVEL is the only real alternative to supply fuel to WWER reactors. All existing fuel suppliers have certified quality management systems which put a special emphasis on the customer satisfaction. This paper attempts to define from the customer's point of view, what are the important issues concerning the customer satisfaction. (author)

233

ITER fuel cycle  

International Nuclear Information System (INIS)

Resulting from the Conceptual Design Activities (1988-1990) by the parties involved in the International Thermonuclear Experimental Reactor (ITER) project, this document summarizes the design requirements and the Conceptual Design Descriptions for each of the principal subsystems and design options of the ITER Fuel Cycle conceptual design. The ITER Fuel Cycle system provides for the handling of all tritiated water and gas mixtures on ITER. The system is subdivided into subsystems for fuelling, primary (torus) vacuum pumping, fuel processing, blanket tritium recovery, and common processes (including isotopic separation, fuel management and storage, and processes for detritiation of solid, liquid, and gaseous wastes). After an introduction describing system function and conceptual design procedure, a summary of the design is presented including a discussion of scope and main parameters, and the fuel design options for fuelling, plasma chamber vacuum pumping, fuel cleanup, blanket tritium recovery, and auxiliary and common processes. Design requirements are defined and design descriptions are given for the various subsystems (fuelling, plasma vacuum pumping, fuel cleanup, blanket tritium recovery, and auxiliary/common processes). The document ends with sections on fuel cycle design integration, fuel cycle building layout, safety considerations, a summary of the research and development programme, costing, and conclusions. Refs, figs and tabs

234

Spent fuel integral experiments  

International Nuclear Information System (INIS)

A series of parallel spent fuel integral experiments are underway at Battelle-Columbus. These experiments are operational in the Battelle hot cell facility and are designed to provide information on effects of cladding degradation on the release of radionuclides from spent fuel waste forms and on combined effects interactions between spent fuel waste forms, the waste package, and the surrounding repository environment. To accomplish these objectives, the integral experiments have been designed the emulate characteristics of repository environments for spent fuel materials in deep-mined repositories in tuff, basalt, and granite media

235

The nuclear fuel cycle  

International Nuclear Information System (INIS)

After a short introduction about nuclear power in the world, fission physics and the French nuclear power plants, this brochure describes in a digest way the different steps of the nuclear fuel cycle: uranium prospecting, mining activity, processing of uranium ores and production of uranium concentrates (yellow cake), uranium chemistry (conversion of the yellow cake into uranium hexafluoride), fabrication of nuclear fuels, use of fuels, reprocessing of spent fuels (uranium, plutonium and fission products), recycling of energetic materials, and storage of radioactive wastes. (J.S.)

236

Nuclear fuel quality assurance  

International Nuclear Information System (INIS)

Full text: Quality assurance is used extensively in the design, construction and operation of nuclear power plants. This methodology is applied to all activities affecting the quality of a nuclear power plant in order to obtain confidence that an item or a facility will perform satisfactorily in service. Although the achievement of quality is the responsibility of all parties participating in a nuclear power project, establishment and implementation of the quality assurance programme for the whole plant is a main responsibility of the plant owner. For the plant owner, the main concern is to achieve control over the quality of purchased products or services through contractual arrangements with the vendors. In the case of purchase of nuclear fuel, the application of quality assurance might be faced with several difficulties because of the lack of standardization in nuclear fuel and the proprietary information of the fuel manufacturers on fuel design specifications and fuel manufacturing procedures. The problems of quality assurance for purchase of nuclear fuel were discussed in detail during the seminar. Due to the lack of generally acceptable standards, the successful application of the quality assurance concept to the procurement of fuel depends on how much information can be provided by the fuel manufacturer to the utility which is purchasing fuel, and in what form and how early this information can be provided. The extent of information transfer is basically set ouf information transfer is basically set out in the individual vendor-utility contracts, with some indirect influence from the requirements of regulatory bodies. Any conflict that exists appears to come from utilities which desire more extensive control over the product they are buying. There is a reluctance on the part of vendors to permit close insight of the purchasers into their design and manufacturing procedures, but there nevertheless seems to be an increasing trend towards release of more information to the purchasers. It appears that the full application of the quality assurance concept in the purchase of fuel and fuel manufacturing services will depend to a large extent on the availability of fuel specification data. On the part of fuel purchasers, there is an obvious interest in getting as many details of fuel specification as possible in order to be able to establish a proper level of control over the quality of their purchases. On the other hand, if such specifications are set up in advance by the purchasers, there are often complaints by the manufacturers that the specifications were set up without proper regard for the latest technical information on fuel performance and for the realities of manufacturing processes and technical capabilities. This problem may be resolved when fuel design activities are properly meshed with a full quality assurance system. Discussions during the seminar showed that the operation of acceptable quality assurance systems is a well-established practice at most of the fuel manufacturers. The fuel purchaser may monitor such a system through quality assurance programme auditing as agreed to the individual vendor-purchaser contracts. In this way confidence may be obtained in the quality of the purchased product. However, it is considered that the further improvement of the relations between fuel manufacturers and purchasers could be achieved through the following actions undertaken at the international level: (1) standardization of fuel specifications and testing procedures; (2) dissemination of information on fuel specifications and their connections with observed fuel failure rate; (3) Establishment of a standardized quality assurance programme for fuel fabrication; (4) establishment of a central information service to assist utility groups in preparing documents and procedures to be used in quality assurance activities

237

Fuel performance, design and development  

International Nuclear Information System (INIS)

The normal fuel configurations for operating 220 MWe and 540 MWe PHWRs are natural uranium dioxide 19-element and 37- element fuel bundle types respectively. The fuel configuration for BWRs is 6 x 6 fuel. So far, about 330 thousand PHWR fuel bundles and 3500 number of BWR bundles have been irradiated in the 14 PHWRs and 2 BWRs. Improvements in fuel design, fabrication, quality control and operating practices are continuously carried out towards improving fuel utilization as well as reducing fuel failure rate. Efforts have been put to improve the fuel bundle utilization by increasing the fuel discharge burnup of the natural uranium bundles The overall fuel failure rate currently is less than 0.1 % . Presently the core discharge burnups in different reactors are around 7500 MWD/TeU. The paper gives the fuel performance experience over the years in the different power reactors and actions taken to improve fuel performance over the years. (author)

238

Oxy-fuel combustion of solid fuels  

DEFF Research Database (Denmark)

Oxy-fuel combustion is suggested as one of the possible, promising technologies for capturing CO2 from power plants. The concept of oxy-fuel combustion is removal of nitrogen from the oxidizer to carry out the combustion process in oxygen and, in most concepts, recycled flue gas to lower the flame temperature. The flue gas produced thus consists primarily of carbon dioxide and water. Much research on the different aspects of an oxy-fuel power plant has been performed during the last decade. Focus has mainly been on retrofits of existing pulverized-coal-fired power plant units. Green-field plants which provide additional options for improvement of process economics are however likewise investigated. Of particular interest is the change of the combustion process induced by the exchange of carbon dioxide and water vapor for nitrogen as diluent. This paper reviews the published knowledge on the oxy-fuel process and focuses particularly on the combustion fundamentals, i.e. flame temperatures and heat transfer, ignition and burnout, emissions, and fly ash characteristics. Knowledge is currently available regarding both an entire oxy-fuel power plant and the combustion fundamentals. However, several questions remain unanswered and more research and pilot plant testing of heat transfer profiles, emission levels, the optimum oxygen excess and inlet oxygen concentration levels, high and low-temperature fire-side corrosion, ash quality, plant operability, and models to predict NOx and SO3 formation is required.

Toftegaard, Maja BØg; Brix, Jacob

2010-01-01

239

Oxy-fuel combustion of solid fuels  

Energy Technology Data Exchange (ETDEWEB)

Oxy-fuel combustion is suggested as one of the possible, promising technologies for capturing CO{sub 2} from power plants. The concept of oxy-fuel combustion is removal of nitrogen from the oxidizer to carry out the combustion process in oxygen and, in most concepts, recycled flue gas to lower the flame temperature. The flue gas produced thus consists primarily of carbon dioxide and water. Much research on the different aspects of an oxy-fuel power plant has been performed during the last decade. Focus has mainly been on retrofits of existing pulverized-coal-fired power plant units. Green-field plants which provide additional options for improvement of process economics are however likewise investigated. Of particular interest is the change of the combustion process induced by the exchange of carbon dioxide and water vapor for nitrogen as diluent. This paper reviews the published knowledge on the oxy-fuel process and focuses particularly on the combustion fundamentals, i.e. flame temperatures and heat transfer, ignition and burnout, emissions, and fly ash characteristics. Knowledge is currently available regarding both an entire oxy-fuel power plant and the combustion fundamentals. However, several questions remain unanswered and more research and pilot plant testing of heat transfer profiles, emission levels, the optimum oxygen excess and inlet oxygen concentration levels, high and low-temperature fire-side corrosion, ash quality, plant operability, and models to predict NOx and SO{sub 3} formation is required. 218 refs., 48 figs., 13 tabs.

Maja B. Toftegaard; Jacob Brix; Peter A. Jensen; Peter Glarborg; Anker D. Jensen [Technical University of Denmark, Lyngby (Denmark). Department of Chemical and Biochemical Engineering

2010-10-15

240

Oxy-fuel combustion of solid fuels  

Energy Technology Data Exchange (ETDEWEB)

Oxy-fuel combustion is suggested as one of the possible, promising technologies for capturing CO{sub 2} from power plants. The concept of oxy-fuel combustion is removal of nitrogen from the oxidizer to carry out the combustion process in oxygen and, in most concepts, recycled flue gas to lower the flame temperature. The flue gas produced thus consists primarily of carbon dioxide and water. Much research on the different aspects of an oxy-fuel power plant has been performed during the last decade. Focus has mainly been on retrofits of existing pulverized-coal-fired power plant units. Green-field plants which provide additional options for improvement of process economics are however likewise investigated. Of particular interest is the change of the combustion process induced by the exchange of carbon dioxide and water vapor for nitrogen as diluent. This paper reviews the published knowledge on the oxy-fuel process and focuses particularly on the combustion fundamentals, i.e. flame temperatures and heat transfer, ignition and burnout, emissions, and fly ash characteristics. Knowledge is currently available regarding both an entire oxy-fuel power plant and the combustion fundamentals. However, several questions remain unanswered and more research and pilot plant testing of heat transfer profiles, emission levels, the optimum oxygen excess and inlet oxygen concentration levels, high and low-temperature fire-side corrosion, ash quality, plant operability, and models to predict NO{sub x} and SO{sub 3} formation is required. (author)

Toftegaard, Maja B. [Department of Chemical and Biochemical Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); DONG Energy, Kraftvaerksvej 53, DK-7000 Fredericia (Denmark); Brix, Jacob; Jensen, Peter A.; Glarborg, Peter; Jensen, Anker D. [Department of Chemical and Biochemical Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark)

2010-10-15

 
 
 
 
241

Fuel cell generator energy dissipator  

Science.gov (United States)

An apparatus and method are disclosed for eliminating the chemical energy of fuel remaining in a fuel cell generator when the electrical power output of the fuel cell generator is terminated. During a generator shut down condition, electrically resistive elements are automatically connected across the fuel cell generator terminals in order to draw current, thereby depleting the fuel

Veyo, Stephen Emery (Murrysville, PA); Dederer, Jeffrey Todd (Valencia, PA); Gordon, John Thomas (Ambridge, PA); Shockling, Larry Anthony (Pittsburgh, PA)

2000-01-01

242

Fuel Cells Vehicle Systems Analysis (Fuel Cell Freeze Investigation)  

Energy Technology Data Exchange (ETDEWEB)

Presentation on Fuel Cells Vehicle Systems Analysis (Fuel Cell Freeze Investigation) for the 2005 Hydrogen, Fuel Cells & Infrastructure Technologies Program Annual Review held in Arlington, Virginia on May 23-26, 2005.

Pesaran, A.; Kim, G.; Markel, T.; Wipke, K.

2005-05-01

243

Failed fuel detection from viewpoint of fuel inspection  

International Nuclear Information System (INIS)

The cause of the failed fuel problem is discussed from the viewpoint of the inspection in fuel processing. Especially the problem of (1) the qualification of cladding and (2) the qualification of fuel rod welding are mentioned in detail. (auth.)

244

Benefits of barrier fuel on fuel cycle economics  

International Nuclear Information System (INIS)

Barrier fuel rod cladding was developed to eliminate fuel rod failures from pellet/cladding stress/corrosion interaction and to eliminate the associated need to restrict the rate at which fuel rod power can be increased. The performance of barrier cladding has been demonstrated through extensive testing and through production application to many boiling water reactors (BWRs). Power reactor data have shown that barrier fuel rod cladding has a significant beneficial effect on plant capacity factor and plant operating costs and significantly increases fuel reliability. Independent of the fuel reliability benefit, it is less obvious that barrier fuel has a beneficial effect of fuel cycle costs, since barrier cladding is more costly to fabricate. Evaluations, measurements, and development activities, however, have shown that the fuel cycle cost benefits of barrier fuel are large. This paper is a summary of development activities that have shown that application of barrier fuel significantly reduces BWR fuel cycle costs

245

TRIGA low enrichment fuel  

International Nuclear Information System (INIS)

Sixty TRIGA reactors have been sold and the earliest of these are now passing twenty years of operation. All of these reactors use the uranium-zirconium hydride fuel (UZrH) which provides certain unique advantages arising out of its large prompt negative temperature coefficient, very low fission product release, and high temperature capability. Eleven of these Sixty reactors are conversions from plate fuel to TRIGA fuel which were made as a result of these advantages. With only a few exceptions, TRIGA reactors have always used low-enriched-uranium (LEU) fuel with an enrichment of 19.9%. The exceptions have either been converted from the standard low-enriched fuel to the 70% enriched FLIP fuel in order to achieve extended lifetime, or are higher powered reactors which were designed for long life using 93%-enriched uranium during the time when the use and export of highly enriched uranium (HEU) was not restricted. The advent of international policies focusing attention on nonproliferation and safeguards made the HEU fuels obsolete. General Atomic immediately undertook a development effort (nearly two years ago) in order to be in a position to comply with these policies for all future export sales and also to provide a low-enriched alternative to fully enriched plate-type fuels. This important work was subsequently partially supported by the U.S. Department of Energy. The laboratory and production tests have shown that higher uranium densities can be achieved to compensate for reducing the enrichment to 20%, and that the fuels maintain the characteristics of the very thoroughly proven standard TRIGA fuels. In May of 1978, General Atomic announced that these fuels were available for TRIGA reactors and for plate-type reactors with power levels up to 15 MW with GA's standard commercial warranty

246

Reprocessing of nuclear fuels  

International Nuclear Information System (INIS)

One of the persistent ideas concerning nuclear power is that the fuel costs are negligible. This, of course, is incorrect and, in fact, one of the major problems in the development of economic nuclear power is to get the cost of the fuel cycles down to an acceptable level. The irradiated fuel removed from the nuclear power reactors must be returned as fresh fuel into the system. Aside from the problems of handling and shipping involved in the reprocessing cycles, the two major steps are the chemical separation and the refabrication. The chemical separation covers the processing of the spent fuel to separate and recover the unburned fuel as well as the new fuel produced in the reactor. This includes the decontamination of these materials from other radioactive fission products formed in the reactor. Refabrication involves the working and sheathing of recycled fuel into the shapes and forms required by reactor design and the economics of the fabrication problem determines to a large extent the quality of the material required from the chemical treatment. At present there appear to be enough separating facilities in the United States and the United Kingdom to handle the recycling of fuel from power reactors for the next few years. However, we understand the costs of recycling fuel in these facilities will be high or low depend ing on whether or not the capital costs of the plant are included in the processing cost. Also, the present plants may not be well adapted to carry out the chemical processing of the very wide variety of power reactor fuel elements which are being considered and will continue to be considered over the years to come. (author)

247

Fuel safety research 2000  

International Nuclear Information System (INIS)

In April 1999, the Fuel Safety Research Laboratory was newly established as a part of reorganization of the Nuclear Safety Research Center, JAERI. The new laboratory was organized by combining three pre-existing laboratories, Reactivity Accident Laboratory, Fuel Reliability Laboratory, and a part of Severe Accident Research Laboratory. The Fuel Safety Research Laboratory becomes to be in charge of all fuel safety research in JAERI. Various experimental and analytical researches are conducted in the laboratory by using the unique facilities such as the Nuclear Safety Research Reactor (NSRR), the Japan Material Testing Reactor (JMTR), the Japan Research Reactor 3 (JRR-3) and hot cells in JAERI. The laboratory consists of following five research groups corresponding to each research fields; (a) Research group of fuel behavior under the reactivity initiated accident conditions (RIA group). (b) Research group of fuel behavior under the loss-of-coolant accident conditions (LOCA group). (c) Research group of fuel behavior under the normal operation conditions (JMTR/BOCA group). (d) Research group of fuel behavior analysis (FEMAXI group). (e) Research group of FP release/transport behavior from irradiated fuel (VEGA group). The research activities in year 2000 produced many important data and information. They are, for example, failure of high burnup BWR fuel rod under RIA conditions, data on the behavior of hydrided Zircaloy cladding under LOCA conditions and FP release data from VEGA experiments at very high temperature/pressure condition. This report summarizes the outline of research activities and major outcomes of the research executed in 2000 in the Fuel Safety Research Laboratory. (author)

248

Fuel safety research 2000  

Energy Technology Data Exchange (ETDEWEB)

In April 1999, the Fuel Safety Research Laboratory was newly established as a part of reorganization of the Nuclear Safety Research Center, JAERI. The new laboratory was organized by combining three pre-existing laboratories, Reactivity Accident Laboratory, Fuel Reliability Laboratory, and a part of Severe Accident Research Laboratory. The Fuel Safety Research Laboratory becomes to be in charge of all fuel safety research in JAERI. Various experimental and analytical researches are conducted in the laboratory by using the unique facilities such as the Nuclear Safety Research Reactor (NSRR), the Japan Material Testing Reactor (JMTR), the Japan Research Reactor 3 (JRR-3) and hot cells in JAERI. The laboratory consists of following five research groups corresponding to each research fields; (a) Research group of fuel behavior under the reactivity initiated accident conditions (RIA group). (b) Research group of fuel behavior under the loss-of-coolant accident conditions (LOCA group). (c) Research group of fuel behavior under the normal operation conditions (JMTR/BOCA group). (d) Research group of fuel behavior analysis (FEMAXI group). (e) Research group of FP release/transport behavior from irradiated fuel (VEGA group). The research activities in year 2000 produced many important data and information. They are, for example, failure of high burnup BWR fuel rod under RIA conditions, data on the behavior of hydrided Zircaloy cladding under LOCA conditions and FP release data from VEGA experiments at very high temperature/pressure condition. This report summarizes the outline of research activities and major outcomes of the research executed in 2000 in the Fuel Safety Research Laboratory. (author)

Uetsuka, Hiroshi (ed.) [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

2001-03-01

249

Plasma sprayed and electrospark deposited zirconium metal diffusion barrier coatings  

Energy Technology Data Exchange (ETDEWEB)

Zirconium metal coatings applied by plasma spraying and electrospark deposition (ESD) have been investigated for use as diffusion barrier coatings on low enrichment uranium fuel for research nuclear reactors. The coatings have been applied to both stainless steel as a surrogate and to simulated nuclear fuel uranium-molybdenum alloy substrates. Deposition parameter development accompanied by coating characterization has been performed. The structure of the plasma sprayed coating was shown to vary with transferred arc current during deposition. The structure of ESD coatings was shown to vary with the capacitance of the deposition equipment.

Hollis, Kendall J [Los Alamos National Laboratory; Pena, Maria I [Los Alamos National Laboratory

2010-01-01

250

Nanofluidic fuel cell  

Science.gov (United States)

Fuel cells are gaining momentum as a critical component in the renewable energy mix for stationary, transportation, and portable power applications. State-of-the-art fuel cell technology benefits greatly from nanotechnology applied to nanostructured membranes, catalysts, and electrodes. However, the potential of utilizing nanofluidics for fuel cells has not yet been explored, despite the significant opportunity of harnessing rapid nanoscale reactant transport in close proximity to the reactive sites. In the present article, a nanofluidic fuel cell that utilizes fluid flow through nanoporous media is conceptualized and demonstrated for the first time. This transformative concept captures the advantages of recently developed membraneless and catalyst-free fuel cell architectures paired with the enhanced interfacial contact area enabled by nanofluidics. When compared to previously reported microfluidic fuel cells, the prototype nanofluidic fuel cell demonstrates increased surface area, reduced activation overpotential, superior kinetic characteristics, and moderately enhanced fuel cell performance in the high cell voltage regime with up to 14% higher power density. However, the expected mass transport benefits in the high current density regime were constrained by high ohmic cell resistance, which could likely be resolved through future optimization studies.

Lee, Jin Wook; Kjeang, Erik

2013-11-01

251

Fuel element stringer construction  

International Nuclear Information System (INIS)

In a fuel element stringer for a gas cooled graphite moderated nuclear reactor, the graphite sleeves of each fuel element are coupled together by spigot and socket formation and bear against one another at mating conical end to afford improved mechanical stiffness and damping when the stringer undergoes raising and lowering movements within the reactor. (author)

252

Nuclear fuel assembly  

International Nuclear Information System (INIS)

Purpose: To improve the fuel economy, increase the thermal margin to burnout and decrease the pressure loss to thereby improve the reactor core stability in fuel assemblies. Constitution: Moderator rods have been disposed at the center of fuel assemblies to effectively moderate neutrons thereby improving the neutron availability. The cross section of the moderator rod occupying the containing space for the fuel rods at the center of the fuel assembly is made square or like other shape and the occupying area is so adapted that a predetermined condition can be satisfied between the outer diameter of the fuel rod and the lattice arrangement pitch and the unit constituent cells of the spacer at the periphery of the fuel rod is partially depleted. Further, protrusions are formed to the surface of the moderator rod so as to keep a distance between them. In this way, the diameter of the moderating rod is increased to sufficiently moderate neutrons thereby improving the fuel economy, decreasing the strain in the steam weight % distribution and increasing the thermal margin. Further, the pressure loss is decreased as well to improve the stability of nuclear hot water. (Kamimura, M.)

253

Nuclear fuel can  

International Nuclear Information System (INIS)

Purpose: To provide nuclear fuel cans capable of load following operation with no worry of stress corrosion cracking. Constitution: If the reactor power rises abruptly in a stage where fuel burnup degree is increased, chemical reactions are taken place between the fuel can and the corrosive nuclear fission products and, at the same time, thermal stresses are exerted on the fuel can due to the heat expansion of nuclear fuel pellets, by which stress corrosion crackings are caused by the combined effects. In view of the above, the inner surface of the fuel can substrate made of zirconium alloy is lined by depositing a graphite layer of 0.5 - 100 ?m thickness. Since the graphite lining can prevent the contact between the fuel can substrate and the corrosive nuclear fission products and the lubricating property of the graphite lining can reduce the frictional coefficient upon contact due to the heat expansion, local stresses can be reduced. Thus, the reliability of the nuclear fuel elements can be improved to practice the load following operation. (Kamimura, M.)

254

Alternative Fuels in Transportation  

Science.gov (United States)

The realization of dwindling fossil fuel supplies and their adverse environmental impacts has accelerated research and development activities in the domain of renewable energy sources and technologies. Global energy demand is expected to rise during the next few decades, and the majority of today's energy is based on fossil fuels. Alternative…

Kouroussis, Denis; Karimi, Shahram

2006-01-01

255

International fuel bank  

International Nuclear Information System (INIS)

The working group discusses the establishment of an international bank for nuclear fuels. The statements by representatives of seven countries discuss the specific features of a bank of this kind which is set up to facilitate access to nuclear fuels but also to permit a more rigid control in the sense of the non-proliferation philosophy

256

Spent nuclear fuel storage  

International Nuclear Information System (INIS)

When a country becomes self-sufficient in part of the nuclear cycle, as production of fuel that will be used in nuclear power plants for energy generation, it is necessary to pay attention for the best method of storing the spent fuel. Temporary storage of spent nuclear fuel is a necessary practice and is applied nowadays all over the world, so much in countries that have not been defined their plan for a definitive repository, as well for those that already put in practice such storage form. There are two main aspects that involve the spent fuels: one regarding the spent nuclear fuel storage intended to reprocessing and the other in which the spent fuel will be sent for final deposition when the definitive place is defined, correctly located, appropriately characterized as to several technical aspects, and licentiate. This last aspect can involve decades of studies because of the technical and normative definitions at a given country. In Brazil, the interest is linked with the storage of spent fuels that will not be reprocessed. This work analyses possible types of storage, the international panorama and a proposal for future construction of a spent nuclear fuel temporary storage place in the country. (author)

257

Fuel pin plenum spring  

International Nuclear Information System (INIS)

A fuel pin including plenum spring consisting of a material having a temperature dependent spring constant so selected as to substantially reduce the spring force when the spring is at reactor operating temperature is described. With this arrangement, the spring force applied during shipping may be relatively high without overstressing the fuel pellets during reactor operation. (author)

258

Fuel cells. Nenryo denchi  

Energy Technology Data Exchange (ETDEWEB)

In this article, the present states of development of high temperature operative fuel cells are introduced and in addition, examples predicting the performance of the system of combined power plants using these fuel cells are introduced. In other words, as for the high temperature operative fuel cell, the molten carbonate fuel cell (MCFC) is referred to and its features are explained and as the present state of the MCFC technologies, the state of development of large capacity stacks, its operating technology and its future prospect are mentioned. As for the solid oxide fuel cell (SOFC), its principle and features are stated and a cylindrical cell as well as a flat cell are introduced as its state of development. Concerning the fuel cell combined power generation system, since it has a potential to achieve very high power generating efficiency over 50% and has merits of diversification of fuel and excellent environmental effects, etc., efforts to pay for achieving its practical application as soon as possible are strongly stressed, but at the same time, many problems yet to be solved for achieving the practical usage of the above two types of fuel cells are pointed out. 6 figs., 3 tabs.

Abe, T. (Central Research Inst. of Electric Power Industry, Tokyo (Japan))

1990-12-15

259

PLATINUM AND FUEL CELLS  

Science.gov (United States)

Platinum requirements for fuel cell vehicles (FCVS) have been identified as a concern and possible problem with FCV market penetration. Platinum is a necessary component of the electrodes of fuel cell engines that power the vehicles. The platinum is deposited on porous electrodes...

260

Fuel Cell Laboratory Exercise  

Science.gov (United States)

This in-class lab exercise gives students the chance to build a zinc- copper fuel cell out of its component parts. The procedure for the lab is provided along with a graphical representation of what the fuel cell should look like. Several student questions are also included. This document may be downloaded in PDF file format.

2012-04-27

 
 
 
 
261

Fuel cells for transportation  

International Nuclear Information System (INIS)

Results of an evaluation of fuel cell applications in city buses, highway buses, consumer vehicles, and delivery vans are briefly reviewed. Results of an economic analysis of the four target vehicles strongly suggest the feasibility of the fuel cell vehicle in the future

262

Nuclear fuel manufacture  

International Nuclear Information System (INIS)

The technologies used to manufacture nuclear fuel from uranium ore are outlined, with particular reference to the light water reactor fuel cycle. Capital and operating cost estimates for the processing stages are given, and the relevance to a developing uranium industry in Australia is discussed

263

Fuel cycle economical improvement by reaching high fuel burnup  

International Nuclear Information System (INIS)

Improvements of fuel utilization in the light water reactors, burnup increase have led to a necessity to revise strategic approaches of the fuel cycle development. Different trends of the fuel cycle development are necessary to consider in accordance with the type of reactors used, the uranium market and other features that correspond to the nuclear and economic aspects of the fuel cycle. The fuel burnup step-by-step extension Program that successfully are being realized by the leading, firms - fuel manufacturers and the research centres allow to say that there are no serious technical obstacles for licensing in the near future of water cooling reactors fuel rod burnup (average) limit to 65-70 MWd/kgU and fuel assembly (average) limit to (60-65) MWd/kgU. The operating experience of Ukrainian NPPs with WWER-1000 is 130 reactor * years. At the beginning of 1999, a total quantity of the fuel FA discharged during all time of operation of 11 reactors was 5819 (110 fuel cycles). Economical improvement is reached by increase of fuel burn-up by using of some FA of 3 fuel cycles design in 4th fuel loading cycle. Fuel reliability is satisfactory. The further improvement of FA is necessary, that will allow to reduce the front-end fuel cycle cost (specific natural uranium expenditure), to reduce spent fuel amount and, respectively, the fuel cycle back end costs, and to increase burn-up of the fuel. (author)

264

Nondestructive measurements on spent fuel for the nuclear fuel cycle  

Energy Technology Data Exchange (ETDEWEB)

Nondestructive measurements on spent fuel are being developed to meet safeguards and materials managment requirements at nuclear facilities. Spent-fuel measurement technology and its applications are reviewed.

Cobb, D.D.; Phillips, J.R.

1980-01-01

265

Marine Fuel Cell Market Analysis.  

Science.gov (United States)

Numerous studies have shown that it is feasible to reform diesel fuel to derive electric power from fuel cells. The improved efficiency, reduced emissions, and other attributes of fuel cells make them an attractive alternative to existing power sources. T...

Z. Karin, N. Leavitt, T. Costa, R. Grijalva

1999-01-01

266

Fuel cells: Problems and prospects  

Digital Repository Infrastructure Vision for European Research (DRIVER)

n recent years, fuel cell technology has advanced significantly. Field trials on certain types of fuel cells have shown promise for electrical use. This article reviews the electrochemistry, problems and prospects of fuel cell systems.

Shukla, Ak; Ramesh, Kv; Kannan, Am

1986-01-01

267

Fuel spill reports-Format  

Science.gov (United States)

Title : Fuel spill reports-Format Type : Antarctic EAM NSF Org: OD / OPP Date : February 05, 1991 ... Action Memorandum (Threshold for Fuel Spill Reports/Format for Fuel Spill Reports) To: Files (S.7 - ...

268

Nuclear fuel pellets  

International Nuclear Information System (INIS)

Purpose: To prevent the rise of gas pressure in fuel rods, as well as decrease the stresses resulted in fuel cans for use in BWR-type reactors. Constitution: Sintered cylindrical fuel pellets containing fissionable materials are made to comprise metal oxides for adjusting the crystal grain size. The crystal grain size in the inner region of the pellet is made larger than that at the outer region. This enables to decrease the releasing rate of the gaseous nuclear fission products without reducing the creep strain velocity of the nuclear fuel pellets. As the result, the iodine concentration in the gap plenum can be decreased so as to prevent the occurrence of excess stresses in the fuel can. (Moriyama, K.)

269

Nuclear fuel cans  

International Nuclear Information System (INIS)

Purpose: To suppress the propagation of stress-corrosion cracks, if occurred, in zircalloy fuel cans for water cooled reactors. Constitution: Face-centered cubic lattice structures have an effect of inhibiting crack propagation since cracks do not concentrate on specific faces due to the isotropy of the structures. Then, if Zr3Al having the fcc lattice structure is crystallized out in zircalloy fuel cans, cracks are inhibited from further propagation at that structures. Actually, aluminum is melted into zircalloy at the ingot propagation stage and then zircalloy fuel cans are fabricated, wherein the weight ratio of aluminum to be melted is restricted within 5 +- 2% in order to crystallize out only Zr3Al and optimize the crystallizing effect while possessing various features of the zircalloy fuel cans. In this manner, by properly crystallizing out different lattice structures in the zircalloy fuel cans, propagation of the cracks can be prevented effectively. (Ikeda, J.)

270

Fuel cells : emerging markets  

International Nuclear Information System (INIS)

This presentation highlighted the findings of the 2009 review of the fuel cell industry and emerging markets as they appeared in Fuel Cell Today (FCT), a benchmark document on global fuel cell activity. Since 2008, the industry has seen a 50 per cent increase in fuel cell systems shipped, from 12,000 units to 18,000 units. Applications have increased for backup power for datacentres, telecoms and light duty vehicles. The 2009 review focused on emerging markets which include non-traditional regions that may experience considerable diffusion of fuel cells within the next 5 year forecast period. The 2009 review included an analysis on the United Arab Emirates, Mexico, Brazil and India and reviewed primary drivers, likely applications for near-term adoption, and government and private sector activity in these regions. The presentation provided a forecast of the global state of the industry in terms of shipments as well as a forecast of countries with emerging markets

271

Uranium plutonium oxide fuels  

International Nuclear Information System (INIS)

Uranium plutonium oxide is the principal fuel material for liquid metal fast breeder reactors (LMFBR's) throughout the world. Development of this material has been a reasonably straightforward evolution from the UO2 used routinely in the light water reactor (LWR's); but, because of the lower neutron capture cross sections and much lower coolant pressures in the sodium cooled LMFBR's, the fuel is operated to much higher discharge exposures than that of a LWR. A typical LMFBR fuel assembly is shown. Depending on the required power output and the configuration of the reactor, some 70 to 400 such fuel assemblies are clustered to form the core. There is a wide variation in cross section and length of the assemblies where the increasing size reflects a chronological increase in plant size and power output as well as considerations of decreasing the net fuel cycle cost. Design and performance characteristics are described

272

Vibration of fuel bundles  

International Nuclear Information System (INIS)

Several mathematical models have been proposed for calculating fuel rod responses in axial flows based on a single rod consideration. The spacing between fuel rods in liquid metal fast breeder reactors is small; hence fuel rods will interact with one another due to fluid coupling. The objective of this paper is to study the coupled vibration of fuel bundles. To account for the fluid coupling, a computer code, AMASS, is developed to calculate added mass coefficients for a group of circular cylinders based on the potential flow theory. The equations of motion for rod bundles are then derived including hydrodynamic forces, drag forces, fluid pressure, gravity effect, axial tension, and damping. Based on the equations, a method of analysis is presented to study the free and forced vibrations of rod bundles. Finally, the method is applied to a typical LMFBR fuel bundle consisting of seven rods

273

Nuclear fuel pellets  

International Nuclear Information System (INIS)

Purpose: To decrease the fuel-cladding mechanical interactions by providing protruded portions at the circumferential surface of a fuel pellet. Constitution: Band-like protrusions are disposed at both of the upper and lower ends on the circumferential surface of a generally cylindrical fuel pellet in which their opposing lateral ends have such corrugated portions that the waveforms of the portions are in the same or adverse phase to each other. If cracks are generated in a band-like axial protrusion of the pellet due to the thermal stresses, the fuel-cladding interactions are generated. However, since there are no fuel substances on both sides of each protruded portions, the cracked portion is divided finely before excess stresses are generated in that portion, whereby the inner surface of the cladding tube can be kept without centralized deformation and protected against stress corrosions and damages. (Moriyama, K.)

274

Nuclear fuel assembly  

International Nuclear Information System (INIS)

A bimetallic spacer means is cooperatively associated with a nuclear fuel assembly and operative to resist the occurrence of in-reactor bowing of the nuclear fuel assembly. The bimetallic spacer means in one embodiment of the invention includes a space grid formed, at least principally, of zircaloy to the external surface of which are attached a plurality of stainless steel strips. In another embodiment the strips are attached to fuel pins. In each of the embodiments, the stainless steel strips during power production expand outwardly to a greater extent than do the members to which the stainless steel strips are attached, thereby forming stiff springs which abut against like bimetallic spacer means with which the other nuclear fuel assemblies are provided in a given nuclear reactor core to thus prevent the occurrence of in-reactor bowing of the nuclear fuel assemblies. (author)

275

Solid oxide fuel cells.  

Science.gov (United States)

Despite being first demonstrated over 160 years ago, and offering significant environmental benefits and high electrical efficiency, it is only in the last two decades that fuel cells have offered a realistic prospect of being commercially viable. The solid oxide fuel cell (SOFC) offers great promise and is presently the subject of intense research activity. Unlike other fuel cells the SOFC is a solid-state device which operates at elevated temperatures. This review discusses the particular issues facing the development of a high temperature solid-state fuel cell and the inorganic materials currently used and under investigation for such cells, together with the problems associated with operating SOFCs on practical hydrocarbon fuels. PMID:12596542

Ormerod, R Mark

2003-01-01

276

Why fuel prices differ  

International Nuclear Information System (INIS)

Fuel taxes differ largely between countries. This paper reviews a number of considerations from the theory of public finance that may explain these differences. Based on a multiple regression model, we find for tax competition in Europe that small countries tend to be more aggressive than large countries by charging lower fuel taxes to attract customers from neighbouring countries. There is strong evidence that fuel is just considered as one of the many sources for government expenditure: as the share of government expenditure in GDP is higher, the fuel tax tends to be higher. No support is found for the hypothesis that fuel taxes are higher in countries where externality problems are more severe (proxied by car density of the country). In this respect, the normative literature on pricing externalities has found little support in the realities of transport policy. (author)

277

Nuclear fuel element  

International Nuclear Information System (INIS)

Purpose: To enable to suppress the leaching of radioactive corrosion products into sodium even if coating layers applied to the surface of a fuel can should fail in nuclear fuel elements used for LMFBR type reactors. Constitution: After sputtering argon ions to the surface of a fuel can containing fuel pellets to the inside and consisting of metal material, followed by washing and smoothing, dual coating layer is formed by ion plating, that is, a nickel layer and, further thereover, a ceramic layer comprising ceramics such as TiN or TiC, or ceramics incorporated with transition metals. The corrosion resistance and abrasion resistance of the ceramic layer can be utilized. In addition, if peeling or cracking is resulted to the ceramic layer, direct contact between the fuel can and sodium at high temperature can be prevented by the nickel layer and radioactive corrosion products are adsorbed and suppressed from leaching. (Horiuchi, T.)

278

Low emissions diesel fuel  

Science.gov (United States)

A method and matter of composition for controlling NO.sub.x emissions from existing diesel engines. The method is achieved by adding a small amount of material to the diesel fuel to decrease the amount of NO.sub.x produced during combustion. Specifically, small amounts, less than about 1%, of urea or a triazine compound (methylol melamines) are added to diesel fuel. Because urea and triazine compounds are generally insoluble in diesel fuel, microemulsion technology is used to suspend or dissolve the urea or triazine compound in the diesel fuel. A typical fuel formulation includes 5% t-butyl alcohol, 4.5% water, 0.5% urea or triazine compound, 9% oleic acid, and 1% ethanolamine. The subject invention provides improved emissions in heavy diesel engines without the need for major modifications.

Compere, Alicia L. (Knoxville, TN); Griffith, William L. (Oak Ridge, TN); Dorsey, George F. (Farragut, TN); West, Brian H. (Kingston, TN)

1998-01-01

279

Nuclear fuel elements  

International Nuclear Information System (INIS)

Purpose: To suppress iodine release thereby prevent stress corrosion cracks in fuel cans by dispersing ferrous oxide at the outer periphery of sintered uranium dioxide pellets filled and sealed within zirconium alloy fuel cans of fuel elements. Constitution: Sintered uranium dioxide pellets to be filled and sealed within a zirconium alloy fuel can are prepared either by mixing ferric oxide powder in uranium dioxide powder, sintering and then reducing at low temperature or by mixing iron powder in uranium dioxide powder, sintering and then oxidizing at low temperature. In this way, ferrous oxide is dispersed on the outer periphery of the sintered uranium dioxide pellets to convert corrosive fission products iodine into iron iodide, whereby the iodine release is suppressed and the stress corrosion cracks can be prevented in the fuel can. (Moriyama, K.)

280

Agricultural transportation fuels  

International Nuclear Information System (INIS)

The recommendations on the title subject are focused on the question whether advantages and disadvantages of agricultural fuels compared to fossil fuels justify the Dutch policy promotion of the use of agricultural products as basic materials for agricultural fuels. Attention is paid to energetic, environmental and economical aspects of both fuel types. Four options to apply agricultural transportation fuels are discussed: (1) 10% bio-ethanol in euro-unleaded gasoline for engines of passenger cars, equipped with a three-way catalyst; (2) the substitution of 15% methyl tertiair butyl ether (MTBE) by ethyl tertiair butyl ether (ETBE) as a substituent for lead in unleaded super plus gasoline (Sp 98) for engines of passenger cars, equipped with a three-way catalyst; (3) 50% KME (rapeseed oil ester) in low-sulfur diesel (0.05%S D) for engines of vans without a catalyst; and (4) the substitution of 0.05% S D by bio-ethanol or KME for buses with fuel-adjusted engines, equipped with a catalyst. Also the substitution by liquefied petroleum gas (LPG), compressed natural gas (CNG) or E 95 was investigated in option four. Each of the options investigated can contribute to a reduction of the use of fossil energy and the environmental effects of the use of fossil fuels, although some environmental effects from agricultural fuels must be taken into consideration. It is recommended to seriously pay attention to the promotion of agricultural fuels, not only in the Netherlands, but also in an international context. Policy instruments to be used in the stimulation of the use of such fuels are the existing European Community subsidies on fallow lands, exemption of the European Community energy levy, and the use of tax differentiation. Large-scale demonstration projects must be started to quantify hazardous emissions and to solve still existing technical problems. 8 figs., 3 tabs., refs., 4 appendices

 
 
 
 
281

FUEL CELLS IN ENERGY PRODUCTION  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The purpose of this thesis is to study fuel cells. They convert chemical energy directly into electrical energy with high efficiency and low emmission of pollutants. This thesis provides an overview of fuel cell technology.The basic working principle of fuel cells and the basic fuel cell system components are introduced in this thesis. The properties, advantages, disadvantages and applications of six different kinds of fuel cells are introduced. Then the efficiency of each fuel cell is p...

Huang, Xiaoyu

2011-01-01

282

Alternate-Fueled Flight: Halophytes, Algae, Bio-, and Synthetic Fuels  

Science.gov (United States)

Synthetic and biomass fueling are now considered to be near-term aviation alternate fueling. The major impediment is a secure sustainable supply of these fuels at reasonable cost. However, biomass fueling raises major concerns related to uses of common food crops and grasses (some also called "weeds") for processing into aviation fuels. These issues are addressed, and then halophytes and algae are shown to be better suited as sources of aerospace fuels and transportation fueling in general. Some of the history related to alternate fuels use is provided as a guideline for current and planned alternate fuels testing (ground and flight) with emphasis on biofuel blends. It is also noted that lessons learned from terrestrial fueling are applicable to space missions. These materials represent an update (to 2009) and additions to the Workshop on Alternate Fueling Sustainable Supply and Halophyte Summit at Twinsburg, Ohio, October 17 to 18, 2007.

Hendricks, R. C.

2012-01-01

283

Safety analysis of MOX fuels by fuel performance code  

Energy Technology Data Exchange (ETDEWEB)

Performance of plutonium rick mixed oxide fuels specified for the Reduced-Moderation Water Reactor (RMWR) has been analysed by modified fuel performance code. Thermodynamic properties of these fuels up to 120 GWd/t burnup have not been measured and estimated using existing uranium fuel models. Fission product release, pressure rise inside fuel rods and mechanical loads of fuel cans due to internal pressure have been preliminarily assessed based on assumed axial power distribution history, which show the integrity of fuel performance. Detailed evaluation of fuel-cladding interactions due to thermal expansion or swelling of fuel pellets due to high burnup will be required for safety analysis of mixed oxide fuels. Thermal conductivity and swelling of plutonium rich mixed oxide fuels shall be taken into consideration. (T. Tanaka)

Suzuki, Motoe [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

2002-12-01

284

Low contaminant formic acid fuel for direct liquid fuel cell  

Science.gov (United States)

A low contaminant formic acid fuel is especially suited toward use in a direct organic liquid fuel cell. A fuel of the invention provides high power output that is maintained for a substantial time and the fuel is substantially non-flammable. Specific contaminants and contaminant levels have been identified as being deleterious to the performance of a formic acid fuel in a fuel cell, and embodiments of the invention provide low contaminant fuels that have improved performance compared to known commercial bulk grade and commercial purified grade formic acid fuels. Preferred embodiment fuels (and fuel cells containing such fuels) including low levels of a combination of key contaminants, including acetic acid, methyl formate, and methanol.

Masel, Richard I. (Champaign, IL); Zhu, Yimin (Urbana, IL); Kahn, Zakia (Palatine, IL); Man, Malcolm (Vancouver, CA)

2009-11-17

285

Spent fuel workshop'2002  

International Nuclear Information System (INIS)

This document gathers the transparencies of the presentations given at the 2002 spent fuel workshop: Session 1 - Research Projects: Overview on the IN CAN PROCESSES European project (M. Cowper), Overview on the SPENT FUEL STABILITY European project (C. Poinssot), Overview on the French R and D project on spent fuel long term evolution, PRECCI (C. Poinssot); Session 2 - Spent Fuel Oxidation: Oxidation of uranium dioxide single crystals (F. Garrido), Experimental results on SF oxidation and new modeling approach (L. Desgranges), LWR spent fuel oxidation - effects of burn-up and humidity (B. Hanson), An approach to modeling CANDU fuel oxidation under dry storage conditions (P. Taylor); Session 3 - Spent Fuel Dissolution Experiments: Overview on high burnup spent fuel dissolution studies at FZK/INE (A. Loida), Results on the influence of hydrogen on spent fuel leaching (K. Spahiu), Leaching of spent UO2 fuel under inert and reducing conditions (Y. Albinsson), Fuel corrosion investigation by electrochemical techniques (D. Wegen), A reanalysis of LWR spent fuel flow through dissolution tests (B. Hanson), U-bearing secondary phases formed during fuel corrosion (R. Finch), The near-field chemical conditions and spent fuel leaching (D. Cui), The release of radionuclides from spent fuel in bentonite block (S.S. Kim), Trace actinide behavior in altered spent fuel (E. Buck, B. Hanson); Session 4 - Radiolysis Issues: The effect of radiolysis on UO2 dissolution determined from electrochemical experiments with 238Pu doped UO2 M. Stroess-Gascoyne (F. King, J.S. Betteridge, F. Garisto), doped UO2 studies (V. Rondinella), Preliminary results of static and dynamic dissolution tests with ? doped UO2 in Boom clay conditions (K. Lemmens), Studies of the behavior of UO2 / water interfaces under He2+ beam (C. Corbel), Alpha and gamma radiolysis effects on UO2 alteration in water (C. Jegou), Behavior of Pu-doped pellets in brines (M. Kelm), On the potential catalytic behavior of UO2(s): experimental approach and preliminary results on uranium oxide - water interface (J. Devoy), Preliminary results on studies on radiolysis effects on dissolution of UO2 (E. Ekeroth, M. Jonnson); Session 5 - Modeling of the Spent Fuel Dissolution: tUO2 dissolution and the effect of radiolysis (T. Lundstrom), Prediction of the effect of radiolysis (F. King), Experimental determination and chemical modeling of radiolytic processes at the spent fuel / water interface (E. Cera, J. Bruno, T. Eriksen, M. Grive, L. Duro); Session 6 - Influence of the Potential Evolution prior to the Water Access on IRF: Potential occurrence of ? self-irradiation enhanced-diffusion (H.J. Matzke, T. Petit), Are grain boundaries a stable microstructure? (Y. Guerin), Modeling RN instant release fractions from spent nuclear fuel under repository conditions (C.Poinssot, L. Johnson, P. Lovera). (J.S.)

286

Direct Methanol Fuel Cell, DMFC  

Directory of Open Access Journals (Sweden)

Full Text Available Direct Methanol Fuel Cell, DMFC is a kind of fuel cell using methanol as a fuel for electric producing. Methanol is low cost chemical substance and it is less harmful than that of hydrogen fuel. From these reasons it can be commercial product. The electrocatalytic reaction of methanol fuel uses Pt-Ru metals as the most efficient catalyst. In addition, the property of membrane and system designation are also effect to the fuel cell efficient. Because of low power of methanol fuel cell therefore, direct methanol fuel cell is proper to use for the energy source of small electrical devices and vehicles etc.

Amornpitoksuk, P.

2003-09-01

287

76 FR 18066 - Regulation of Fuels and Fuel Additives: Changes to Renewable Fuel Standard Program  

Science.gov (United States)

...ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 80 Regulation of Fuels and Fuel Additives: Changes to Renewable Fuel Standard Program CFR Correction In Title 40 of the Code of Federal Regulations, Parts 72 to...

2011-04-01

288

77 FR 72746 - Regulation of Fuels and Fuel Additives: Modifications to Renewable Fuel Standard and Diesel...  

Science.gov (United States)

...PROTECTION AGENCY 40 CFR Part 80 [EPA-HQ-OAR-2012-0223; FRL- 9758-8] Regulation of Fuels and Fuel Additives: Modifications to Renewable Fuel Standard and Diesel Sulfur Programs AGENCY: Environmental Protection Agency (EPA)....

2012-12-06

289

Alkaline fuel cells applications  

Science.gov (United States)

On the world-wide automobile market technical developments are increasingly determined by the dramatic restriction on emissions as well as the regimentation of fuel consumption by legislation. Therefore there is an increasing chance of a completely new technology breakthrough if it offers new opportunities, meeting the requirements of resource preservation and emission restrictions. Fuel cell technology offers the possibility to excel in today's motive power techniques in terms of environmental compatibility, consumer's profit, costs of maintenance and efficiency. The key question is economy. This will be decided by the costs of fuel cell systems if they are to be used as power generators for future electric vehicles. The alkaline hydrogen-air fuel cell system with circulating KOH electrolyte and low-cost catalysed carbon electrodes could be a promising alternative. Based on the experiences of Kordesch [K. Kordesch, Brennstoffbatterien, Springer, Wien, 1984, ISBN 3-387-81819-7; K. Kordesch, City car with H 2-air fuel cell and lead-battery, SAE Paper No. 719015, 6th IECEC, 1971], who operated a city car hybrid vehicle on public roads for 3 years in the early 1970s, improved air electrodes plus new variations of the bipolar stack assembly developed in Graz are investigated. Primary fuel choice will be a major issue until such time as cost-effective, on-board hydrogen storage is developed. Ammonia is an interesting option. The whole system, ammonia dissociator plus alkaline fuel cell (AFC), is characterised by a simple design and high efficiency.

Kordesch, Karl; Hacker, Viktor; Gsellmann, Josef; Cifrain, Martin; Faleschini, Gottfried; Enzinger, Peter; Fankhauser, Robert; Ortner, Markus; Muhr, Michael; Aronson, Robert R.

290

Hydrogen as automotive fuel  

International Nuclear Information System (INIS)

Hydrogen fueled vehicles may just be the answer to the air pollution problem in highly polluted urban environments where the innovative vehicle's air pollution abatement characteristics would justify its high operating costs as compared with those of conventional automotive alternatives. This paper examines the feasibility of hydrogen as an automotive fuel by analyzing the following aspects: the chemical-physical properties of hydrogen in relation to its use in internal combustion engines; the modifications necessary to adapt internal combustion engines to hydrogen use; hydrogen fuel injection systems; current production technologies and commercialization status of hydrogen automotive fuels; energy efficiency ratings; environmental impacts; in-vehicle storage systems - involving the use of hydrides, high pressure systems and liquid hydrogen storage systems; performance in terms of pay-load ratio; autonomous operation; and operating costs. With reference to recent trial results being obtained in the USA, an assessment is also made of the feasibility of the use of methane-hydrogen mixtures as automotive fuels. The paper concludes with a review of progress being made by ENEA (the Italian Agency for New Technology, Energy and the Environment) in the development of fuel storage and electronic fuel injection systems for hydrogen powered vehicles

291

Alternative fuel from agriculture  

Energy Technology Data Exchange (ETDEWEB)

Alcohol gas from wood combustion and vegetable oils are possible alternative fuels for tractors. The first two of these substances require expensive adaptation of Diesel engines. By contrast, one can make optimum use of the energy conversion of the Diesel engine with vegetable oils. Only slight changes have to be made to the Diesel engine. Experiments on a test rig using linseed oil, sunflower seed oil, soya oil and rape oil mixed with petroleum products have shown that mixing with Diesel fuel presents no problems. The mixtures are stable. There is no corrosion of formation of resin in the fuel system. However, oils, which are liable to form resin, such as linseed oil should not be used. Steyr injection engines with mechanically regulated injection pumps and without fuel heating could be operated with a proportion of up to 75% of vegetable oil, and those with hydraulically regulated injection pumps with a proportion of 25% of vegetable oil. Practical experiments with a fuel consisting of 50% rape oil and 50% Diesel fuel caused deposits on the piston, the piston rings and valves, from which it seems that a standard of quality is required. In spite of world wide research, the use of vegetable oils in Diesel fuel is not being considered at present.

1982-01-01

292

Bio-fuels barometer  

International Nuclear Information System (INIS)

European Union bio-fuel use for transport reached 12 million tonnes of oil equivalent (mtoe) threshold during 2009. The slowdown in the growth of European consumption deepened again. Bio-fuel used in transport only grew by 18.7% between 2008 and 2009, as against 30.3% between 2007 and 2008 and 41.8% between 2006 and 2007. The bio-fuel incorporation rate in all fuels used by transport in the E.U. is unlikely to pass 4% in 2009. We can note that: -) the proportion of bio-fuel in the German fuels market has plummeted since 2007: from 7.3% in 2007 to 5.5% in 2009; -) France stays on course with an incorporation rate of 6.25% in 2009; -) In Spain the incorporation rate reached 3.4% in 2009 while it was 1.9% in 2008. The European bio-diesel industry has had another tough year. European production only rose by 16.6% in 2009 or by about 9 million tonnes which is well below the previous year-on-year growth rate recorded (35.7%). France is leading the production of bio-ethanol fuels in Europe with an output of 1250 million liters in 2009 while the total European production reached 3700 million litters and the world production 74000 million liters. (A.C.)

293

Inert matrix fuel (IMF)  

International Nuclear Information System (INIS)

The state of development and future perspectives of nuclear fuel with inert (non-fissionable) matrix for thermal and fast reactors are considered. Engineering requirements towards matrix materials for fuel pellets are formulated. The wet and dry processes of manufacturing the powder materials for matrices and fissionable compositions using co-deposition of powders following the nitrate technology and formation of microspheres by sol-gel method, as well as preparation of powders by mechanical treatment are described. It is shown that application of the fuel with inert matrix provides opportunities for sufficient increasing the utilization of available weapon plutonium, as well as the plutonium regenerated from spent uranium fuel, fuel burnup improvement, thorium involving into the fuel cycle and decreasing amounts of the fuel, which should be disposed. The conclusion is made that the oxide ceramics ZrO2, MgAl2O4, CeO2, Y3Al5O12, MgO are the most suitable for using as the materials for inert matrices

294

Fuel cell. Nenryo denchi  

Energy Technology Data Exchange (ETDEWEB)

This invention concerns a fuel cell in which a manifold supplying and exhausting gas collectively is attached to the fuel cell main body laminating, through separators, pairs of gas diffusion electrodes, each pair of which consists of a fuel electrode and an oxidizing agent electrode both having a respective gas channel. The existing fuel cell of this kind has such problems, inter alia, that gas does not flow smoothly depending upon the composition of gas at the inlet as well as the outlet, in other words, the gas density difference between the inside of the fuel inlet and outlet manifolds. Hence as a countermeasure, in order to obtain an uniform gas flow all around the upper and lower sides of the inside of the manifolds without affecting the plant efficiency and the size of the stack, etc. even when a density difference at the inlet and the outlet occurs, this invention proposes, with regard to the above fuel cell, to solve the flow problems based on the above gas density difference by providing on the separator protuberances whose shape and number are designed optimally in accordance with the manifold height so that the gas channel may be partially blocked or the channel resistance may be increased, or the channel resistance of the gas channel of the electrode, in particular that on the side of the fuel electrode may increase. 9 figs.

Takemoto, Toshiaki; Naniwa, keisho.

1989-12-26

295

Hydrogen vehicle fueling station  

Energy Technology Data Exchange (ETDEWEB)

Hydrogen fueling stations are an essential element in the practical application of hydrogen as a vehicle fuel, and a number of issues such as safety, efficiency, design, and operating procedures can only be accurately addressed by a practical demonstration. Regardless of whether the vehicle is powered by an internal combustion engine or fuel cell, or whether the vehicle has a liquid or gaseous fuel tank, the fueling station is a critical technology which is the link between the local storage facility and the vehicle. Because most merchant hydrogen delivered in the US today (and in the near future) is in liquid form due to the overall economics of production and delivery, we believe a practical refueling station should be designed to receive liquid. Systems studies confirm this assumption for stations fueling up to about 300 vehicles. Our fueling station, aimed at refueling fleet vehicles, will receive hydrogen as a liquid and dispense it as either liquid, high pressure gas, or low pressure gas. Thus, it can refuel any of the three types of tanks proposed for hydrogen-powered vehicles -- liquid, gaseous, or hydride. The paper discusses the fueling station design. Results of a numerical model of liquid hydrogen vehicle tank filling, with emphasis on no vent filling, are presented to illustrate the usefulness of the model as a design tool. Results of our vehicle performance model illustrate our thesis that it is too early to judge what the preferred method of on-board vehicle fuel storage will be in practice -- thus our decision to accommodate all three methods.

Daney, D.E.; Edeskuty, F.J.; Daugherty, M.A. [Los Alamos National Lab., NM (United States)] [and others

1995-09-01

296

Method of regulating nuclear fuels  

International Nuclear Information System (INIS)

Purpose: To enable substantially load-depending operation by regulating the power of fuel elements comprising fuel pellets tightly shield within a metal fuel can in a range where fuel-cladding interaction is low. Method: A fuel element comprises fuel pellets and a metal cladding tube with a radial clearance therebetween, and with an axial plenum containing a spring for axial expansion of the pellets. The both ends of the fuel can are welded with end plugs respectively so as to tightly seal the fuel elements. Then, the fuel elements are regulated by raising the power thereof to a desired maximum power level at a power up ratio smaller than the critical power up ratio. This enables to regulate the fuel elements in a range where the fuel-cladding interaction is low and perform nearly load depending operation. (Moriyama, K.)

297

Fossil Fuels: Capstone  

Science.gov (United States)

This lesson summarizes our dependency upon fossil fuels, pointing out that there are very few aspects of our daily life that are not impacted by their use. The discussion centers around whether these fuels could be replaced and makes the point that there is a significant percentage of them which is used to manufacture products and is not simply burned for energy. The lesson includes an activity in which students use an online calculator to estimate how much of each fossil fuel they are responsible for consuming each year.

Pratte, John

298

Molten carbonate fuel cell  

Science.gov (United States)

A molten electrolyte fuel cell with an array of stacked cells and cell enclosures isolating each cell except for access to gas manifolds for the supply of fuel or oxidant gas or the removal of waste gas, the cell enclosures collectively providing an enclosure for the array and effectively avoiding the problems of electrolyte migration and the previous need for compression of stack components, the fuel cell further including an inner housing about and in cooperation with the array enclosure to provide a manifold system with isolated chambers for the supply and removal of gases. An external insulated housing about the inner housing provides thermal isolation to the cell components.

Kaun, Thomas D. (New Lenox, IL); Smith, James L. (Lemont, IL)

1987-01-01

299

Nuclear reactor fuel unit  

International Nuclear Information System (INIS)

The object of this invention is to harness the force of the ascending coolant of the reactor to actuate a locking mechanism holding the fuel unit in position against the core support. The invention makes for easy unlocking of the unit so as to facilitate its removal. The fuel unit is held in position near its lower end by a compact device, of easy fabrication and use, that does not cause any significant drop in the pressure of the coolant in the reactor vessel. Under the invention, the fuel unit can be unlocked from a distance in the event of any failure of the normal locking components

300

Fuel rod technology  

International Nuclear Information System (INIS)

By extensive mechanization and automation of the fuel rod production, also at increasing production numbers, an efficient production shall be secured, simultaneously corresponding to the high quality standard of the fuel rods. The works done up to now concentrated on the lay out of a rough concept for a mechanized production course. Detail-studies were made for the problems of fuel rod humidity, filling and resistance welding. Further promotion of this project and thus further report will be stopped, since the main point of these works is the production technique. (orig.)

 
 
 
 
301

Enigma fuel performance code  

International Nuclear Information System (INIS)

The Enigma fuel performance code has been developed jointly by BNFL and the CEGB's Berkeley Nuclear Laboratories. Its development arose from the need for a code capable of analysing all aspects of light water reactor (LWR) fuel behaviour which would also provide a suitable framework for future submodel development. The submodels incorporated into Enigma reflect the significant progress which has been made in recent years in modelling the important physical processes which determine fuel behaviour. The Enigma code has been subjected to an extensive programme of validation which has demonstrated its suitability for LWR performance analysis. (author)

302

Fuel for CAGR stations  

International Nuclear Information System (INIS)

The design of the fuel stringer consisting of 8 elements and other components is described. The heat transfer performance of the 36 pin element was extensively studied in laboratory tests. Identical pins of stainless steel clad hollow UO2 pellets were irradiated in the prototype Windscale AGR in 9 pin elements: the programme included studies of the effect of rating changes. Extensive post-irradiation examination was made of a wide variety of properties. The behaviour of the complete fuel assembly for the commercial stations under handling and flow conditions has been studied in large gas loops. The early fuel history at Hinkley Point 'B' and Hunterston 'B' stations is summarised. (author)

303

Distillate Fuel Processing for Marine Fuel Cell Applications.  

Science.gov (United States)

FuelCell Energy, Inc. (FCE) is developing a 625 kW fuel cell power plant for marine applications based on its Direct Carbonate Fuel Cell (DFC(Trademark)) technology. The power plant is designed for operation on Mil-F- 16884J Naval distillate fuel designat...

G. Steinfield, R. Sanderson, H. Ghezel-Ayagh, S. Abens, M. C. Cervi

2000-01-01

304

Heating subsurface formations by oxidizing fuel on a fuel carrier  

Science.gov (United States)

A method of heating a portion of a subsurface formation includes drawing fuel on a fuel carrier through an opening formed in the formation. Oxidant is supplied to the fuel at one or more locations in the opening. The fuel is combusted with the oxidant to provide heat to the formation.

Costello, Michael; Vinegar, Harold J.

2012-10-02

305

Design package for fuel retrieval system fuel handling tool modification  

International Nuclear Information System (INIS)

This is a design package that contains the details for a modification to a tool used for moving fuel elements during loading of MCO Fuel Baskets for the Fuel Retrieval System. The tool is called the fuel handling tool (or stinger). This document contains requirements, development design information, tests, and test reports

306

Detection of failed fuel rods in shrouded BWR fuel assemblies  

International Nuclear Information System (INIS)

A manipulator and an ultrasonic testing (UT) technique were developed to identify defective fuel rods in shrouded BWR fuel assemblies. The manipulator drives a UT probe axially through the bottom tie plate into the water channels between the fuel rods. The rotating UT probe locates defective fuel rods by ingressed water which attenuates the UT-signal. (author)

307

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: ENVIROFUELS DIESEL FUEL CATALYZER FUEL ADDITIVE  

Science.gov (United States)

EPA's Environmental Technology Verification Program has tested EnviroFuels diesel fuel additive, called the Diesel Fuel Catalyzer. EnviroFuels has stated that heavy-duty on and off road diesel engines are the intended market for the catalyzer. Preliminary tests conducted indicate...

308

GENUSA Fuel Evolution  

Energy Technology Data Exchange (ETDEWEB)

GNF ENUSA Nuclear Fuel S.A. (GENUSA) was formed in Madrid in May 1996. GENUSA is a corporation organized and existing under the laws of Spain, jointly owned by GNF-A and ENUSA. GENUSA consolidates all European BWR fuel marketing activities of GNF-A and ENUSA, primarily providing marketing and project management. In its standard way of operating, it will obtain engineering, components and conversion from GNF-A and engineering, fabrication and fuel related services from ENUSA. GENUSA's development philosophy over the past decades has been to introduce evolutionary designs, supported by our global experience base, that deliver the performance needed by our customers to meet their operating strategies. GENUSA considers, as one of our strengths, the ever-increasing experience base that provides the foundation for such evolutionary changes. This experience is supported and complemented with an even greater GNF experience. Over the last 40 years, GNF and ENUSA have designed, fabricated, and placed in operation over 144,000 BWR fuel bundles containing over 9.7 million fuel rods. This experience base represents the widest range of operating conditions of any BWR fuel vendor, reflecting varying reactor power densities, operating strategies, and water chemistry environments. It covers operating periods of up to {approx}10 years and bundle average exposures up to 68 MWd/kgU.. It provides the confirmation of our understanding and ability to model fuel performance behavior, and has been instrumental in the identification and characterization of each encountered failure mechanism. With the knowledge gained from this extensive experience base, mitigating actions have been developed and progressively implemented by GENUSA as part of a continuous program toward improved fuel reliability and performance. GENUSA's evolutionary product introduction strategy has been extremely successful. There has been a continuous stream of new products/processes that were developed to deliver improved performance. Relative to the 8x8 fuel operated in the 1980's, today's designs provide {approx}25% more efficiency and power capability and twice as much energy. Because of GENUSA's evolutionary design commitment, these product improvements have been successfully rolled out to our customers with no design or fabrication-related performance surprises. Additionally, this has been accomplished with an accompanying steady improvement in fuel reliability. In the past three decades, fuel reliability has improved by approximately three orders of magnitude. That is, the fuel rod leaker rate has been reduced from over five hundred rods per million operating, to less than ten. In past decades, most plants experienced failures each cycle, and fleet-wide failure mechanisms drove reliability statistics. Today, a small minority of our customers' plants experience failures in any cycle, mainly recurrent, low level debris fretting failures in a handful of plants. GENUSA is committed to providing the most robust, and balanced, fuel solutions to our customers based on our extensive experience and technological capabilities. Identifying and successfully mitigating the mechanisms that cause fuel failures has been instrumental in this observed improvement in fuel reliability. GENUSA systematically identified and eliminated mechanisms leading to failure through pool-side and hot cell examinations, and feedback of lessons learned into the design and fabrication of the fuel. Some of the highly successful mitigating actions during this history include: - Improved pellet fabrication in the 1970's to eliminate cladding primary hydride failures; - Corrosion-resistant cladding, with a chemistry and microstructure specifically targeted to protect against crud-induced corrosion (CILC) failures; - Improved cladding and welding fabrication and inspection techniques that assured the hermeticity and quality of the delivered fuel rod; - Tightened pellet missing surface specifications to add PCI margin; - Introduction of a debris filter, applied as a standard fe

Choithramani, Sylvia; Malpica, Maria [ENUSA Industrias Avanzadas, GENUSA, Josefa Valcarcel, 26 28027 Madrid (Spain); Fawcett, Russel [Global Nuclear Fuel (United States)

2009-06-15

309

78 FR 77119 - Proposed Information Collection Request; Comment Request; Regulation of Fuels and Fuel Additives...  

Science.gov (United States)

...Collection Request; Comment Request; Regulation of Fuels and Fuel Additives: 2011 Renewable Fuel Standards-- Petition for...collection request (ICR), ``Regulation of Fuels and Fuel Additives: 2011 Renewable Fuel Standards--Petition...

2013-12-20

310

40 CFR 79.56 - Fuel and fuel additive grouping system.  

Science.gov (United States)

...2010-07-01 false Fuel and fuel additive grouping system. 79.56 ...REGISTRATION OF FUELS AND FUEL ADDITIVES Testing Requirements for Registration § 79.56 Fuel and fuel additive grouping system. (a)...

2010-07-01

311

40 CFR 1065.120 - Fuel properties and fuel temperature and pressure.  

Science.gov (United States)

... false Fuel properties and fuel temperature and pressure. 1065.120...120 Fuel properties and fuel temperature and pressure. (a) Use fuels...engine manufacturer specifies fuel temperature and pressure tolerances...

2010-07-01

312

Ammonia as a suitable fuel for fuel cells  

Directory of Open Access Journals (Sweden)

Full Text Available Ammonia, an important basic chemical, is produced at a scale of 150 million tons per year. Half of hydrogen produced in chemical industry is used for ammonia production. Ammonia containing 17.5wt% hydrogen is an ideal carbon-free fuel for fuel cells. Compared to hydrogen, ammonia has many advantages. In this mini-review, the suitability of ammonia as fuel for fuel cells, the development of different types of fuel cells using ammonia as the fuel and the potential applications of ammonia fuel cells are briefly reviewed.

ShanwenTao

2014-08-01

313

Second International Conference on CANDU Fuel  

International Nuclear Information System (INIS)

Thirty-four papers were presented at this conference in sessions dealing with international experience and programs relating to CANDU fuel; fuel manufacture; fuel behaviour; fuel handling, storage and disposal; and advanced CANDU fuel cycles. (L.L.)

314

Features of fuel performance at high fuel burnups  

International Nuclear Information System (INIS)

Some features of fuel behavior at high fuel burnups, in particular, initiation and development of rim-layer, increase in the rate of fission gas release from the fuel and increase in the inner gas pressure in the fuel rod are briefly described. Basing on the analysis of the data of post-irradiation examinations of fuel rods of WWER-440 working FA and CR fuel followers, that have been operated for five fuel cycles and got the average fuel burnup or varies as 50MW-day/kgU, a conclusion is made that the WWER-440 fuel burnup can be increased at least to average burnups of 55-58 MW-day/kgU per fuel assembly (Authors)

315

Solid fuels encyclopedia  

Energy Technology Data Exchange (ETDEWEB)

This builder's and operator's manual will meet the expectations of a wide audience including general readers, students, fuel dealers, stove manufacturers, home owners, economists, ecologists, building contractors, and architects. Its unusual chapter format, which includes sections on the physical and chemical aspects of burning, fuel, stoves, fireplaces, installation, operation, safety, and the economics of solid fuel burning, encourages an inspection of all its pages. Many line drawings, graphs, and charts augment the text. The glossary is limited, but most of the terms are defined and explained; their use in the text is also indexed. The author also provides caution about restrictions on the use of solid fuel units, such as cost and building code restrictions.

Shelton, J.W.

1983-01-01

316

Fuel cell pioneer  

telecommunications company with a strong presence in India, China ... Economic \\and Social Research Council (ESRC), the Natural Environment ... growth regions \\such as India and Africa and in working with our partners to make fuel cells a.

317

Fuel cycle studies  

International Nuclear Information System (INIS)

Programs are being conducted in the following areas: advanced solvent extraction techniques, accident consequences, fuel cycles for nonproliferation, pyrochemical and dry processes, waste encapsulation, radionuclide transport in geologic media, hull treatment, and analytical support for LWBR

318

Fuel cell cogeneration  

Energy Technology Data Exchange (ETDEWEB)

The U.S. Department of Energy`s Morgantown Energy Technology Center (METC) sponsors the research and development of engineered systems which utilize domestic fuel supplies while achieving high standards of efficiency, economy, and environmental performance. Fuel cell systems are among the promising electric power generation systems that METC is currently developing. Buildings account for 36 percent of U.S. primary energy consumption. Cogeneration systems for commercial buildings represent an early market opportunity for fuel cells. Seventeen percent of all commercial buildings are office buildings, and large office buildings are projected to be one of the biggest, fastest-growing sectors in the commercial building cogeneration market. The main objective of this study is to explore the early market opportunity for fuel cells in large office buildings and determine the conditions in which they can compete with alternative systems. Some preliminary results and conclusions are presented, although the study is still in progress.

Wimer, J.G. [Dept. of Energy, Morgantown, WV (United States); Archer, D.

1995-08-01

319

Nuclear fuel transport  

International Nuclear Information System (INIS)

The fuel manufacturer receives enriched UF6 and fabricates reactor fuel elements which are shipped to the reactor station. From there the spent fuel elements have to be transported to the reprocessing plant in heavily shielded containers. In the reprocessing plant uranium of low enrichment and plutonium are recovered. Uranium is shipped to the conversion and enrichment plant, whereas plutonium is directly transported to the fuel manufacturer in the form of nitrate solution or oxyde. The regulations for the transport of radioactive (including fissile) materials are based on rules established by IAEA. Though the IAEA rules are only recommendations, they are accepted worldwide and have been introduced into national and international transport regulations for dangerous goods. The principle of the IAEA regulations is to provide safety by the packaging itself in order to minimize additional surveillance and safety measures during shipment. For this purpose there are detailed requirements for packaging. (orig./TK)

320

LIGNITE FUEL ENHANCEMENT  

Energy Technology Data Exchange (ETDEWEB)

This 4th quarterly Technical Progress Report for the Lignite Fuel Enhancement Project summarizes activities from April 1st through June 30th of 2005. It also summarizes the subsequent purchasing activity and dryer/process construction.

Charles Bullinger

2005-07-07

 
 
 
 
321

LIGNITE FUEL ENHANCEMENT  

Energy Technology Data Exchange (ETDEWEB)

This 3rd quarterly Technical Progress Report for the Lignite Fuel Enhancement Project summarizes activities from January 1st through March 31st of 2005. It also summarizes the subsequent purchasing activity and final dryer/process design.

Charles Bullinger

2005-06-07

322

Integral-fuel blocks  

International Nuclear Information System (INIS)

A prismatic moderator block is described which has fuel-containing channels and coolant channels disposed parallel to each other and to edge faces of the block. The coolant channels are arranged in rows on an equilateral triangular lattice pattern and the fuel-containing channels are disposed in a regular lattice pattern with one fuel-containing channel between and equidistant from each of the coolant channels in each group of three mutually adjacent coolant channels. The edge faces of the block are parallel to the rows of coolant channels and the channels nearest to each edge face are disposed in two rows parallel thereto, with one of the rows containing only coolant channels and the other row containing only fuel-containing channels. (Official Gazette)

323

Renewable jet fuel.  

Science.gov (United States)

Novel strategies for sustainable replacement of finite fossil fuels are intensely pursued in fundamental research, applied science and industry. In the case of jet fuels used in gas-turbine engine aircrafts, the production and use of synthetic bio-derived kerosenes are advancing rapidly. Microbial biotechnology could potentially also be used to complement the renewable production of jet fuel, as demonstrated by the production of bioethanol and biodiesel for piston engine vehicles. Engineered microbial biosynthesis of medium chain length alkanes, which constitute the major fraction of petroleum-based jet fuels, was recently demonstrated. Although efficiencies currently are far from that needed for commercial application, this discovery has spurred research towards future production platforms using both fermentative and direct photobiological routes. PMID:24679258

Kallio, Pauli; Pásztor, András; Akhtar, M Kalim; Jones, Patrik R

2014-04-01

324

Nuclear fuel waste disposal  

International Nuclear Information System (INIS)

This report discusses events and processes that could adversely affect the long-term stability of a nuclear fuel waste disposal vault or the regions of the geosphere and the biosphere to which radionuclides might migrate from such a vault

325

Fuel gas from biodigestion  

Science.gov (United States)

Biodigestion apparatus produces fuel gas (primarily methane) for domestic consumption, by anaerobic bacterial digestion of organic matter such as aquatic vegetation. System includes 3,786-1 cylindrical container, mechanical agitator, and simple safe gas collector for short term storage.

Mcdonald, R. C.; Wolverton, B. C.

1979-01-01

326

Packing Nuclear Fuel  

International Science & Technology Center (ISTC)

Development of Scientific Foundations of the Technology of the Metal Matrix Packing of Leaky Unreprocessible Spent Nuclear Fuel of Different Purpose Reactors for a Long-term Environmentally Safe Storage.

327

Alternative fuel information sources  

Energy Technology Data Exchange (ETDEWEB)

This short document contains a list of more than 200 US sources of information (Name, address, phone number, and sometimes contact) related to the use of alternative fuels in automobiles and trucks. Electric-powered cars are also included.

1994-06-01

328

Cooking up fuel  

Science.gov (United States)

Wouldn't it be wonderful if we could solve our waste and energy problems at the same time, by turning one into the other? Attempts have been made to do just that, by making fuel from waste through pyrolysis.

Inman, Mason

2012-04-01

329

North Korea's corroding fuel  

International Nuclear Information System (INIS)

The roughly 8,000 irradiated or open-quotes spentclose quotes fuel rods recently discharged from the North Korean 25 megawatt (thermal) reactor are difficult to store safely under the conditions in the spent fuel ponds near the reactor. The magnesium alloy jacket, or open-quotes cladding,close quotes around the fuel elements is corroding. If the corrosion creates holes in the cladding, radionuclides may be released. In addition, the uranium metal underneath the cladding may begin to corrode, possibly creating uranium hydride which can spontaneously ignite in air. Unless the storage conditions are improved, North Korea may use the risk posed by the corrosion as an argument for reprocessing this fuel, a violation of its June 1994 pledge to the United States to freeze its nuclear program. North Korea, however, can take several steps to slow dramatically the rate of corrosion. Using available techniques, it can extend safe storage times by months or even years

330

Secondary fuel delivery system  

Science.gov (United States)

A secondary fuel delivery system for delivering a secondary stream of fuel and/or diluent to a secondary combustion zone located in the transition piece of a combustion engine, downstream of the engine primary combustion region is disclosed. The system includes a manifold formed integral to, and surrounding a portion of, the transition piece, a manifold inlet port, and a collection of injection nozzles. A flowsleeve augments fuel/diluent flow velocity and improves the system cooling effectiveness. Passive cooling elements, including effusion cooling holes located within the transition boundary and thermal-stress-dissipating gaps that resist thermal stress accumulation, provide supplemental heat dissipation in key areas. The system delivers a secondary fuel/diluent mixture to a secondary combustion zone located along the length of the transition piece, while reducing the impact of elevated vibration levels found within the transition piece and avoiding the heat dissipation difficulties often associated with traditional vibration reduction methods.

Parker, David M. (Oviedo, FL); Cai, Weidong (Oviedo, FL); Garan, Daniel W. (Orlando, FL); Harris, Arthur J. (Orlando, FL)

2010-02-23

331

Solid Oxide Fuel Cell  

International Science & Technology Center (ISTC)

Development and Demonstration of the Advance Technology of New Type Production of Pipe High Temperature Solid Oxide Fuel Cells and Making of Pilot Samples of these Elements for Standard Conditions of Application in Electrochemical Current Sources

332

Organic fuel cells and fuel cell conducting sheets  

Science.gov (United States)

A passive direct organic fuel cell includes an organic fuel solution and is operative to produce at least 15 mW/cm.sup.2 when operating at room temperature. In additional aspects of the invention, fuel cells can include a gas remover configured to promote circulation of an organic fuel solution when gas passes through the solution, a modified carbon cloth, one or more sealants, and a replaceable fuel cartridge.

Masel, Richard I. (Champaign, IL); Ha, Su (Champaign, IL); Adams, Brian (Savoy, IL)

2007-10-16

333

Optical fuel spray measurements  

Energy Technology Data Exchange (ETDEWEB)

Diesel fuel sprays, including fuel/air mixing and the physics of two-phase jet formation, are discussed in the thesis. The fuel/air mixing strongly affects emissions formation in spray combustion processes where the local combustion conditions dictate the emission formation. This study comprises optical measurements both in pressurized spray test rigs and in a running engine.The studied fuel injection was arranged with a common rail injection system and the injectors were operated with a solenoid-based injection valve. Both marine and heavy-duty diesel engine injectors were used in the study. Optical fuel spray measurements were carried out with a laser-based double-framing camera system. This kind of equipments is usually used for flow field measurements with Particle Image Velocimetry technique (PIV) as well as for backlight imaging. Fundamental fuel spray properties and spray formation were studied in spray test rigs. These measurements involved studies of mixing, atomization, and the flow field. Test rig measurements were used to study the effect of individual injection parameters and component designs. Measurements of the fuel spray flow field, spray penetration, spray tip velocity, spray angle, spray structure, droplet accumulation, and droplet size estimates are shown. Measurement campaign in a running optically accessible large-bore medium-speed engine was also carried out. The results from engine tests were compared with equivalent test rig measurements, as well as computational results, to evaluate the level of understanding of sprays. It was shown that transient spray has an acceleration and a deceleration phase. Successive flow field measurements (PIV) in optically dense diesel spray resulted in local and average velocity data of diesel sprays. Processing fuel spray generates a flow field to surrounding gas and entrainment of surrounding gas into fuel jet was also seen at the sides of the spray. Laser sheet imaging revealed the inner structure of diesel spray and accumulation of droplets. Also shockwave formation was recorded when supersonic fuel jet exits the nozzle orifice. These results were used to evaluate spray formation and the structure was compared with simulated fuel sprays. Novel information, more refined and focused results, and better understanding of the nature of atomization and sprays was gathered. It was shown that new methods enable more precise understanding of transient two-phase sprays to be gained. (orig.)

Hillamo, H.

2011-07-01

334

Handbook of fuel cell performance  

Energy Technology Data Exchange (ETDEWEB)

The intent of this document is to provide a description of fuel cells, their performances and operating conditions, and the relationship between fuel processors and fuel cells. This information will enable fuel cell engineers to know which fuel processing schemes are most compatible with which fuel cells and to predict the performance of a fuel cell integrated with any fuel processor. The data and estimates presented are for the phosphoric acid and molten carbonate fuel cells because they are closer to commercialization than other types of fuel cells. Performance of the cells is shown as a function of operating temperature, pressure, fuel conversion (utilization), and oxidant utilization. The effect of oxidant composition (for example, air versus O/sub 2/) as well as fuel composition is examined because fuels provided by some of the more advanced fuel processing schemes such as coal conversion will contain varying amounts of H/sub 2/, CO, CO/sub 2/, CH/sub 4/, H/sub 2/O, and sulfur and nitrogen compounds. A brief description of fuel cells and their application to industrial, commercial, and residential power generation is given. The electrochemical aspects of fuel cells are reviewed. The phosphoric acid fuel cell is discussed, including how it is affected by operating conditions; and the molten carbonate fuel cell is discussed. The equations developed will help systems engineers to evaluate the application of the phosphoric acid and molten carbonate fuel cells to commercial, utility, and industrial power generation and waste heat utilization. A detailed discussion of fuel cell efficiency, and examples of fuel cell systems are given.

Benjamin, T.G.; Camara, E.H.; Marianowski, L.G.

1980-05-01

335

Fuel element for nuclear reactors  

International Nuclear Information System (INIS)

In order to avoid coolant leakages after fuel can ruptures in nuclear reactors with fuel rod clusters, it is proposed to ventilate each fuel rod separately at its upper end with the aid of a capillary tube. The capillary tubes are led through the upper end of the can into a chamber above the fuel rods. (UWI) 891 HP

336

Advanced Fuels Campaign 2012 Accomplishments  

Energy Technology Data Exchange (ETDEWEB)

The Advanced Fuels Campaign (AFC) under the Fuel Cycle Research and Development (FCRD) program is responsible for developing fuels technologies to support the various fuel cycle options defined in the DOE Nuclear Energy Research and Development Roadmap, Report to Congress, April 2010. The fiscal year 2012 (FY 2012) accomplishments are highlighted below. Kemal Pasamehmetoglu is the National Technical Director for AFC.

Not Listed

2012-11-01

337

Seventh Edition Fuel Cell Handbook  

Energy Technology Data Exchange (ETDEWEB)

Provides an overview of fuel cell technology and research projects. Discusses the basic workings of fuel cells and their system components, main fuel cell types, their characteristics, and their development status, as well as a discussion of potential fuel cell applications.

NETL

2004-11-01

338

MICROBIAL FUEL CELL  

DEFF Research Database (Denmark)

A novel microbial fuel cell construction for the generation of electrical energy. The microbial fuel cell comprises: (i) an anode electrode, (ii) a cathode chamber, said cathode chamber comprising an in let through which an influent enters the cathode chamber, an outlet through which an effluent depart the cathode chamber, a cathode electrode and an electrolyte permeable membrane, wherein both the anode electrode and the cathode chamber are to be submersed into an anaerobic environment to generate electrical energy.

Angelidaki, Irini Technical University of Denmark,

339

Composite fuel cell membranes  

Science.gov (United States)

A bilayer or trilayer composite ion exchange membrane suitable for use in a fuel cell. The composite membrane has a high equivalent weight thick layer in order to provide sufficient strength and low equivalent weight surface layers for improved electrical performance in a fuel cell. In use, the composite membrane is provided with electrode surface layers. The composite membrane can be composed of a sulfonic fluoropolymer in both core and surface layers.

Plowman, Keith R. (Lake Jackson, TX); Rehg, Timothy J. (Lake Jackson, TX); Davis, Larry W. (West Columbia, TX); Carl, William P. (Marble Falls, TX); Cisar, Alan J. (Cypress, TX); Eastland, Charles S. (West Columbia, TX)

1997-01-01

340

Mixed oxide fuel performance  

International Nuclear Information System (INIS)

Following the final shutdown of DFR in March 1977, the examination of irradiation experiments from the last reactor loading has continued. These have included subassemblies at up to 14.7% burnup with four intermediate examinations and single fuel pins at up to 21% burnup which have been examined at ten burnup increments. Results are presented on clad strain development as a function of temperature, neutron dose, burnup and cladding material and on microstructural features of both fuel and clad

 
 
 
 
341

Fuels for Transportation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

There is a need to reduce the amount of fossil energy used for transport, both because of the easily available fossil fuel is becoming sparser and because of climate concerns. In this article, the concept of “peak oil” is briefly presented. Second, a practical approach to reduction of fossil fuel use for transport elaborated by two British commissions is presented. A key feature is the introduction of electric cars. This raises the third issue covered in this article: namely, how battery ...

Fredholm, Bertil B.; Norde?n, Bengt

2010-01-01

342

Nuclear fuel elements  

International Nuclear Information System (INIS)

A nuclear fuel element is described having a cluster of nuclear fuel pins supported in parallel, spaced apart relationship by transverse cellular braces within coaxial, inner and outer sleeves, the inner sleeve being in at least two separate axial lengths, each of the transverse braces having a peripheral portion which is clamped peripherally between the ends of the axial lengths of the inner sleeve. (author)

343

Fuel reprocessing world prospective  

International Nuclear Information System (INIS)

Reprocessing should be considered as the reference solution for spent fuel management, as it allows recovering and recycling of reusable materials, uranium and plutonium, and the reduction of ultimate residues at the lowest level possible. Plutonium production and proliferation issues may be solved through the use of MOX fuels, which enables a zero (or even negative) plutonium balance. Regulations concerning ultimate wastes, whether they will authorize maximum levels at 1% or 0.1% of plutonium, will influence reprocessing future prospects

344

Irradiation of fuels  

International Nuclear Information System (INIS)

The BR2 reactor is used for neutron irradiation of Light Water Reactor and Boiling Water fuels under relevant operating and monitoring conditions as specified by the experimenter's requirements. In 2003, power transient tests have been performed on four BWR segments. Further development work was done for preparing the long term irradiation of LWR fuel in the high-pressure facility CALLISTO in the BR2 reactor

345

Nuclear Fuel Management Optimization  

Energy Technology Data Exchange (ETDEWEB)

The nuclear fuel management design optimization problem has grown more challenging and important with the passage of time. In this paper, we summarize our research on this design optimization problem. A suite of computer codes that aid in making nuclear fuel management decisions has been developed. These codes utilize stochastic optimization techniques to search the decision space for determining the family of near-optimum decisions in the suboptimization problem being solved.

Karve, A.A.; Keller, P.M.; Turinsky, P.J.; Maldonado, G.I.

2001-06-17

346

Nuclear Fuel Management Optimization  

International Nuclear Information System (INIS)

The nuclear fuel management design optimization problem has grown more challenging and important with the passage of time. In this paper, we summarize our research on this design optimization problem. A suite of computer codes that aid in making nuclear fuel management decisions has been developed. These codes utilize stochastic optimization techniques to search the decision space for determining the family of near-optimum decisions in the suboptimization problem being solved

347

Scintillator spent fuel monitor  

Energy Technology Data Exchange (ETDEWEB)

A monitor for rapidly measuring the gross gamma-ray flux immediately above spent fuel assemblies in underwater storage racks has been developed. It consists of a plastic scintillator, photomultiplier, collimator, and a small battery-powered electronics package. The crosstalk from an isolated fuel assembly to an adjacent void is only about 2%. The mean difference between the measured gamma-ray flux and the flux estimated from the declared burnup and cooling time with a simple formula is 22%.

Moss, C.E.; Nixon, K.V.; Bernard, W.

1980-01-01

348

IFR fuel cycle  

International Nuclear Information System (INIS)

The next major milestone of the IFR program is engineering-scale demonstration of the pyroprocess fuel cycle. The EBR-II Fuel Cycle Facility has just entered a startup phase, which includes completion of facility modifications and installation and cold checkout of process equipment. This paper reviews the development of the electrorefining pyroprocess, the design and construction of the facility for the hot demonstration, the design and fabrication of the equipment, and the schedule and initial plan for its operation

349

Environmentally safe aviation fuels  

Science.gov (United States)

In response to the Air Force directive to remove Ozone Depleting Chemicals (ODC's) from military specifications and Defense Logistics Agency's Hazardous Waste Minimization Program, we are faced with how to ensure a quality aviation fuel without using such chemicals. Many of these chemicals are found throughout the fuel and fuel related military specifications and are part of test methods that help qualify the properties and quality of the fuels before they are procured. Many years ago there was a directive for military specifications to use commercially standard test methods in order to provide standard testing in private industry and government. As a result the test methods used in military specifications are governed by the American Society of Testing and Materials (ASTM). The Air Force has been very proactive in the removal or replacement of the ODC's and hazardous materials in these test methods. For example, ASTM D3703 (Standard Test Method for Peroxide Number of Aviation Turbine Fuels), requires the use of Freon 113, a known ODC. A new rapid, portable hydroperoxide test for jet fuels similar to ASTM D3703 that does not require the use of ODC's has been developed. This test has proved, in limited testing, to be a viable substitute method for ASTM D3703. The Air Force is currently conducting a round robin to allow the method to be accepted by ASTM and therefore replace the current method. This paper will describe the Air Force's initiatives to remove ODC's and hazardous materials from the fuel and fuel related military specifications that the Air Force Wright Laboratory.

Liberio, Patricia D.

1995-01-01

350

Fast breeder fuel cycle  

International Nuclear Information System (INIS)

Basic elements of the ex-reactor part of the fuel cycle (reprocessing, fabrication, waste handling and transportation) are described. Possible technical and proliferation measures are evaluated, including current methods of accountability, surveillance and protection. The reference oxide based cycle and advanced cycles based on carbide and metallic fuels are considered utilizing conventional processes; advanced nonaqueous reprocessing is also considered. This contribution provides a comprehensive data base for evaluation of proliferation risks

351

Compliant fuel cell system  

Science.gov (United States)

A fuel cell assembly comprising at least one metallic component, at least one ceramic component and a structure disposed between the metallic component and the ceramic component. The structure is configured to have a lower stiffness compared to at least one of the metallic component and the ceramic component, to accommodate a difference in strain between the metallic component and the ceramic component of the fuel cell assembly.

Bourgeois, Richard Scott (Albany, NY); Gudlavalleti, Sauri (Albany, NY)

2009-12-15

352

Fuel Cell History  

Science.gov (United States)

This paper from George Wand outlines the history of fuel cells and hydrogen use, beginning with historical information on battery powered electric vehicles and moving through the decades and development of a variety of different vehicles. The end of the report takes a brief look into the possible future of hydrogen and fuel cell technologies to power automobiles. This document may be downloaded in PDF file format.

Wand, George

2012-09-14

353

Nuclear fuel assembly  

International Nuclear Information System (INIS)

Purpose: To project ducts communicating with a flowpath box on a upper tie-plate, and cause the vapor of coolants to flow out of the fuel assembly, thereby effectively performing flowing-in of cooling water in an emergency. Constitution: Ducts are provided protuberantly on the outer wall surface at the upper end of the flowpath box of the fuel assembly. Each of the ducts has an enclosed bottom, an opened upper part and a hollow part communicating with the water vent hole of the flowpath box. Cooling water sprayed from the spray nozzle passes through water flowing holes from the upper part of a tie-plate and flows in the nuclear fuel assemblies. Vapor generated therein flows out of the fuel assemblies by passing through water flowing holes and duct hollow parts. Accordingly, pressures within the fuel assemblies can be reduced and the flowing-in of cooling water from the water flowing holes to the fuel assemblies can be performed effectively. (Yoshino, Y.)

354

FFTF driver fuel experience  

International Nuclear Information System (INIS)

The Fast Flux Test Facility is a 400 MWt, sodium-cooled, loop-type reactor located in Richland, Washington. by the end of Cycle 3, after 336 equivalent full power days the driver fuel achieved the initial design burnup of 80 MWd/kg with flawless performance. Because of the excellent performance of the driver fuel assemblies up to their design lifetime is was decided to extend the irradiation of several assemblies to establish the actual lifetime limit. As a result of the continuing irradiation it was confirmed that the lifetime of the driver fuel assemblies could be extended to a peak duct fluence of about 17.5 x 1022 n/cm2 (E > 0.1 MeV). The demonstration that the lifetime of the driver fuel assembly was duct fluence limited rather than fuel pin burnup limited has been further confirmed by the fact that over a third of the assemblies irradiated in FFTF since the initial power demonstration have exceeded 80 MWd/kgM. As a result of its high reliability the driver fuel system lifetime is now about 100 MWd/kgM in the inner enrichment zone corresponding to the fast fluence limit for the duct of 17.5 x 1022 n/cm2

355

Fuel cladding tube  

International Nuclear Information System (INIS)

Zirconium liner is formed on the inner surface of a base material of a fuel cladding tube made of a zirconium alloy (for example, zircaloy-2). A low purity zirconium (sponge zirconium) is used as the zirconium liner. The low purity zirconium contains 600ppm of Fe and 500ppm of oxygen as main impurities. The crystals of low purity zirconium constituting the zirconium liner have a fr value of 0.65 or greater in the radial direction of the fuel cladding tube. The fr value is a relative ratio of a c-axis of crystals oriented in parallel with the radial direction of fuel cladding tube. Since a drawing fabrication is applied to the fuel cladding tube so as to concentrate the c-axis of the crystals to the radial direction of the fuel cladding tube, a possibility of stress corrosion cracks is lowered. Accordingly, a fuel cladding tube having high reliability with less failure possibility can be attained. (I.N.)

356

Liquid fuel concept benefits  

International Nuclear Information System (INIS)

There are principle drawbacks of any kind of solid nuclear fuel listed and analyzed in the first part of the paper. One of the primary results of the analyses performed shows that the solid fuel concept, which was to certain degree advantageous in the first periods of a nuclear reactor development and operation, has guided this branch of a utilization of atomic nucleus energy to a death end. On the background of this, the liquid fuel concept and its benefits are introduced and briefly described in the first part of the paper, too. As one of the first realistic attempts to utilize the advantages of liquid fuels, the reactor/blanket system with molten fluoride salts in the role of fuel and coolant simultaneously, as incorporated in the accelerator-driven transmutation technology (ADTT) being proposed and currently having been under development in the Los Alamos National Laboratory, will be studied both theoretically and experimentally. There is a preliminary design concept of an experimental assembly LA-O briefly introduced in the paper which is under preparation in the Czech Republic for such a project. Finally, there will be another very promising concept of a small low power ADTT system introduced which is characterized by a high level of safety and economical efficiency. In the conclusion, the overall survey of principal benefits which may be expected by introducing liquid nuclear fuel in nuclear power and research reactor systems is given and critically analyzed. 7 refs, 4 figs

357

Fuel assembly inspection device  

International Nuclear Information System (INIS)

The present invention provides a device suitable to inspect appearance of fuel assemblies by photographing the appearance of fuel assemblies. Namely, the inspection device of the present invention measures bowing of fuel assembly or each of fuel rods or both of them based on the partially photographed images of fuel assembly. In this case, there is disposed a means which flashily projects images in the form of horizontal line from a direction intersecting obliquely relative to a horizontal cross section of the fuel assembly. A first image processing means separates the projected image pictures including projected images and calculates bowing. A second image processing means replaces the projected image pictures of the projected images based on projected images just before and after the photographing. Then, images for the measurement of bowing and images for inspection can be obtained simultaneously. As a result, the time required for the photographing can be shortened, the time for inspection can be shortened and an effect of preventing deterioration of photographing means by radiation rays can be provided. (I.S.)

358

Fuel cycle management  

International Nuclear Information System (INIS)

The fuel cycle management is more and more dependent on the management of the generation means among the power plants tied to the grid. This is due mainly because of the importance taken by the nuclear power plants within the power system. The main task of the fuel cycle management is to define the refuelling pattern of the new and irradiated fuel assemblies to load in the core as a function of: 1) the differences which exist between the actual conditions of the core and what was expected for the present cycle, 2) the operating constraints and the reactor availability, 3) the technical requirements in safety and the technological limits of the fuel, 4) the economics. Three levels of fuel cycle management can be considered: 1) a long term management: determination of enrichments and expected cycle lengths, 2) a mid term management whose aim corresponds to the evaluation of the batch to load within the core as a function of both: the next cycle length to achieve and the integrated power history of all the cycles up to the present one, 3) a short term management which deals with the updating of the loaded fuel utilisations to take into account the operation perturbations, or with the alteration of the loading pattern of the next batch to respect unexpected conditions. (orig.)

359

Alternative Fuels: Research Progress  

Directory of Open Access Journals (Sweden)

Full Text Available Chapter 1: Pollutant Emissions and Combustion Characteristics of Biofuels and Biofuel/Diesel Blends in Laminar and Turbulent Gas Jet Flames. R. N. Parthasarathy, S. R. Gollahalli Chapter 2: Sustainable Routes for The Production of Oxygenated High-Energy Density Biofuels from Lignocellulosic Biomass. Juan A. Melero, Jose Iglesias, Gabriel Morales, Marta Paniagua Chapter 3: Optical Investigations of Alternative-Fuel Combustion in an HSDI Diesel Engine. T. Huelser, M. Jakob, G. Gruenefeld, P. Adomeit, S. Pischinger Chapter 4: An Insight into Biodiesel Physico-Chemical Properties and Exhaust Emissions Based on Statistical Elaboration of Experimental Data. Evangelos G. Giakoumis Chapter 5: Biodiesel: A Promising Alternative Energy Resource. A.E. Atabani Chapter 6: Alternative Fuels for Internal Combustion Engines: An Overview of the Current Research. Ahmed A. Taha, Tarek M. Abdel-Salam, Madhu Vellakal Chapter 7: Investigating the Hydrogen-Natural Gas Blends as a Fuel in Internal Combustion Engine. ?lker YILMAZ Chapter 8: Conversion of Bus Diesel Engine into LPG Gaseous Engine; Method and Experiments Validation. M. A. Jemni , G. Kantchev , Z. Driss , R. Saaidia , M. S. Abid Chapter 9: Predicting the Combustion Performance of Different Vegetable Oils-Derived Biodiesel Fuels. Qing Shu, ChangLin Yu Chapter 10: Production of Gasoline, Naphtha, Kerosene, Diesel, and Fuel Oil Range Fuels from Polypropylene and Polystyrene Waste Plastics Mixture by Two-Stage Catalytic Degradation using ZnO. Moinuddin Sarker, Mohammad Mamunor Rashid

Maher A.R. Sadiq Al-Baghdadi

2013-01-01

360

Direct Methanol Fuel Cell, DMFC  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Direct Methanol Fuel Cell, DMFC is a kind of fuel cell using methanol as a fuel for electric producing. Methanol is low cost chemical substance and it is less harmful than that of hydrogen fuel. From these reasons it can be commercial product. The electrocatalytic reaction of methanol fuel uses Pt-Ru metals as the most efficient catalyst. In addition, the property of membrane and system designation are also effect to the fuel cell efficient. Because of low power of methanol fuel cell therefor...

Amornpitoksuk, P.

2003-01-01

 
 
 
 
361

Advanced CANDU fuel cycle vision  

International Nuclear Information System (INIS)

The natural uranium fuel Cycle and currently developed advanced CANDU fuel cycles in the near future are described. High neutron economy, on line refueling and a simple fuel bundle design result in unsurpassed fuel cycle flexibility and variety for CANDU reactors. These features facilitate the introduction and exploitation of advanced fuel cycles in existing CANDU reactors, without requiring major modification. These advanced fuel cycles include the use of slight enriched uranium (SEU), use of re-cycled uranium (RU) from reprocessing spent PWR fuel, direct use of spent PWR fuel in CANDU (DUPIC), use of plutonium-containing mixed-oxide (MOX) fuel, thorium fuel cycle and actinide burning in CANDU reactors. Especially the LWR/CANDU synergism is of great economical and practical significance for the countries possessing both of the LWR and CANDU nuclear power plants

362

EPRI fuel cladding integrity program  

International Nuclear Information System (INIS)

The objectives of the EPRI fuel program is to supplement the fuel vendor research to assure that utility economic and operational interests are met. To accomplish such objectives, EPRI has conducted research and development efforts to (1) reduce fuel failure rates and mitigate the impact of fuel failures on plant operation, (2) provide technology to extend burnup and reduce fuel cycle cost. The scope of R ampersand D includes fuel and cladding. In this paper, only R ampersand D related to cladding integrity will be covered. Specific areas aimed at improving fuel cladding integrity include: (1) Fuel Reliability Data Base; (2) Operational Guidance for Defective Fuel; (3) Impact of Water Chemistry on Cladding Integrity; (4) Cladding Corrosion Data and Model; (5) Cladding Mechanical Properties; and (6) Transient Fuel Cladding Response

363

EPRI fuel cladding integrity program  

Energy Technology Data Exchange (ETDEWEB)

The objectives of the EPRI fuel program is to supplement the fuel vendor research to assure that utility economic and operational interests are met. To accomplish such objectives, EPRI has conducted research and development efforts to (1) reduce fuel failure rates and mitigate the impact of fuel failures on plant operation, (2) provide technology to extend burnup and reduce fuel cycle cost. The scope of R&D includes fuel and cladding. In this paper, only R&D related to cladding integrity will be covered. Specific areas aimed at improving fuel cladding integrity include: (1) Fuel Reliability Data Base; (2) Operational Guidance for Defective Fuel; (3) Impact of Water Chemistry on Cladding Integrity; (4) Cladding Corrosion Data and Model; (5) Cladding Mechanical Properties; and (6) Transient Fuel Cladding Response.

Yang, R. [Electric Power Research Institute, Palo Alto, CA (United States)

1997-01-01

364

Deep desulfurization of hydrocarbon fuels  

Science.gov (United States)

The invention relates to processes for reducing the sulfur content in hydrocarbon fuels such as gasoline, diesel fuel and jet fuel. The invention provides a method and materials for producing ultra low sulfur content transportation fuels for motor vehicles as well as for applications such as fuel cells. The materials and method of the invention may be used at ambient or elevated temperatures and at ambient or elevated pressures without the need for hydrogen.

Song, Chunshan (State College, PA); Ma, Xiaoliang (State College, PA); Sprague, Michael J. (Calgary, CA); Subramani, Velu (State College, PA)

2012-04-17

365

Solar Fuels: Vision and Concepts  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The world needs new, environmentally friendly and renewable fuels to allow an exchange from fossil fuels. The fuel must be made from cheap and ‘endless’ resources that are available everywhere. The new research area on solar fuels, which are made from solar energy and water, aims to meet this demand. The paper discusses why we need a solar fuel and why electricity is not enough; it proposes solar energy as the major renewable energy source to feed from. The present research strategies, in...

Styring, Stenbjo?rn

2012-01-01

366

Fuel performance in water storage  

International Nuclear Information System (INIS)

Westinghouse Idaho Nuclear Company operates the Idaho Chemical Processing Plant (ICPP) at the Idaho National Engineering Laboratory (INEL) for the Department of Energy (DOE). A variety of different types of fuels have been stored there since the 1950's prior to reprocessing for uranium recovery. In April of 1992, the DOE decided to end fuel reprocessing, changing the mission at ICPP. Fuel integrity in storage is now viewed as long term until final disposition is defined and implemented. Thus, the condition of fuel and storage equipment is being closely monitored and evaluated to ensure continued safe storage. There are four main areas of fuel storage at ICPP: an original underwater storage facility (CPP-603), a modern underwater storage facility (CPP-666), and two dry fuel storage facilities. The fuels in storage are from the US Navy, DOE (and its predecessors the Energy Research and Development Administration and the Atomic Energy Commission), and other research programs. Fuel matrices include uranium oxide, hydride, carbide, metal, and alloy fuels. In the underwater storage basins, fuels are clad with stainless steel, zirconium, and aluminum. Also included in the basin inventory is canned scrap material. The dry fuel storage contains primarily graphite and aluminum type fuels. A total of 55 different fuel types are currently stored at the Idaho Chemical Processing Plant. The corrosion resistance of the barrier material is of primary concern in evaluating the integrity of the fuel in long term water storage. The barrier material is either the fuel cladding (if not canned) or the can material

367

Apparatus and method for grounding compressed fuel fueling operator  

Science.gov (United States)

A safety system for grounding an operator at a fueling station prior to removing a fuel fill nozzle from a fuel tank upon completion of a fuel filling operation is provided which includes a fuel tank port in communication with the fuel tank for receiving and retaining the nozzle during the fuel filling operation and a grounding device adjacent to the fuel tank port which includes a grounding switch having a contact member that receives physical contact by the operator and where physical contact of the contact member activates the grounding switch. A releasable interlock is included that provides a lock position wherein the nozzle is locked into the port upon insertion of the nozzle into the port and a release position wherein the nozzle is releasable from the port upon completion of the fuel filling operation and after physical contact of the contact member is accomplished.

Cohen, Joseph Perry (Bethlehem, PA); Farese, David John (Riegelsville, PA); Xu, Jianguo (Wrightstown, PA)

2002-06-11

368

Advanced fuels for fast reactors  

International Nuclear Information System (INIS)

Full text: In addition to traditional fast reactor fuels that contain Uranium and Plutonium, the advanced fast reactor fuels are likely to include the minor actinides [Neptunium (Np), Americium (Am) and Curium (Cm)]. Such fuels are also referred to as transmutation fuels. The goal of transmutation fuel development programs is to develop and qualify a nuclear fuel system that performs all of the functions of a traditional fast spectrum nuclear fuel while destroying recycled actinides. Oxide, metal, nitride, and carbide fuels are candidates under consideration for this application, based on historical knowledge of fast reactor fuel development and specific fuel tests currently being conducted in international transmutation fuel development programs. Early fast reactor developers originally favored metal alloy fuel due to its high density and potential for breeder operation. The focus of pressurized water reactor development on oxide fuel and the subsequent adoption by the commercial nuclear power industry, however, along with early issues with low burnup potential of metal fuel (now resolved), led later fast reactor development programs to favor oxide fuels. Carbide and nitride fuels have also been investigated but are at a much lower state of development than metal and oxide fuels, with limited large scale reactor irradiation experience. Experience with both metal and oxide fuels has established that either fuel type will meet performance and reliability goals for a plperformance and reliability goals for a plutonium fueled fast spectrum test reactor, both demonstrating burnup capability of up to 20 at.% under normal operating conditions, when clad with modified austenitic or ferritic martensitic stainless steel alloys. Both metal and oxide fuels have been shown to exhibit sufficient margin to failure under transient conditions for successful reactor operation. Summary of selected fuel material properties taken are provided in the paper. The main challenge for the development of transmutation fast reactor fuels originates from goals for achieving high burnup, operating at higher temperature, and the incorporation of the minor actinides (Np, Am, Cm) into the fuels. High burn-ups will allow uninterrupted reactor operations over longer periods of time and consequently, reduction of spent fuel volumes, and eventually a significant fuel cycle reduction cost. High burn-ups are however associated with physical limitations which are primary due to the swelling of the fuel and oxidation of cladding inner surface as well as the dimensional stability of core materials such as cladding and subassembly duct due to high fast neutron dose. Higher temperature operation also challenges the performance of cladding materials and hence advanced cladding materials are needed for high temperature operation. The irradiation performance database for (U,Pu)N mixed nitride (MN) fuels is substantially smaller than that for metal carbide (MC) fuels, and these fuels can be considered to be at an early stage of development relative to oxide and metal fuels. Compared to MC fuels, MN fuels exhibit less fuel swelling, lower fission gas release, however, the problem of the production of biologically hazardous 14C in nitride fuels fabricated using natural nitrogen poses a considerable concern for the nitride spent fuel waste management. Interest remains in nitride fuels due to the combination of high thermal conductivity and high melting point. The paper also addresses the technology readiness level (TRL) concept as applied to various fuel options. (author)

369

Progress of the DUPIC Fuel Compatibility Analysis (IV) - Fuel Performance  

Energy Technology Data Exchange (ETDEWEB)

This study describes the mechanical compatibility of the direct use of spent pressurized water reactor (PWR) fuel in Canada deuterium uranium (CANDU) reactors (DUPIC) fuel, when it is loaded into a CANDU reactor. The mechanical compatibility can be assessed for the fuel management, primary heat transport system, fuel channel, and the fuel handling system in the reactor core by both the experimental and analytic methods. Because the physical dimensions of the DUPIC fuel bundle adopt the CANDU flexible (CANFLEX) fuel bundle design which has already been demonstrated for a commercial use in CANDU reactors, the experimental compatibility analyses focused on the generation of material property data and the irradiation tests of the DUPIC fuel, which are used for the computational analysis. The intermediate results of the mechanical compatibility analysis have shown that the integrity of the DUPIC fuel is mostly maintained under the high power and high burnup conditions even though some material properties like the thermal conductivity is a little lower compared to the uranium fuel. However it is required to slightly change the current DUPIC fuel design to accommodate the high internal pressure of the fuel element. It is also strongly recommended to perform more irradiation tests of the DUPIC fuel to accumulate a database for the demonstration of the DUPIC fuel performance in the CANDU reactor.

Choi, Hang Bok; Ryu, Ho Jin; Roh, Gyu Hong; Jeong, Chang Joon; Park, Chang Je; Song, Kee Chan; Lee, Jung Won

2005-10-15

370

Fuel thermal behaviour  

International Nuclear Information System (INIS)

The interest in the thermal behaviour of the fuel mainly comes from the safety criterion which prohibit any fuel melting in the pins. Due to the gap lying between fuel and cladding, the highest temperatures are most probably occurring at Beginning Of Life (BOL) before completion of the central hole formation and before any substantial gap closure has taken place. However it cannot be ruled out that after some burn up the thermal transfer between fuel and cladding becomes worse than it was at BOL Then if the power does not decrease the maximum temperature might become higher than at (BOL). In order to get an overall experimental validation of our thermal calculations we need to cover the entire range of the pin life. Actually the method cannot be the same for BOL and end of life (EOL). For BOL it is possible to get a direct thermal measure through thermocouples, but this method is no longer practical after some days due to the failure of the thermocouples under neutrons flux at the temperatures of interest. This failure may happen before or after complete gap closure is reached and the rate of gap closure is especially meaningful for the BOL thermal behaviour. Another aspect of the thermal behaviour is the statistical one which may be obtained by the post-irradiation examination of the fuel microstructure, although it is not a proper way to get the absolute temperatures in the fuel, it is one of the most direct ones to have an insight in fuel thermal dispersion at BOL and over-heating at EOL

371

Hydrogen: Fueling the Future  

Energy Technology Data Exchange (ETDEWEB)

As our dependence on foreign oil increases and concerns about global climate change rise, the need to develop sustainable energy technologies is becoming increasingly significant. Worldwide energy consumption is expected to double by the year 2050, as will carbon emissions along with it. This increase in emissions is a product of an ever-increasing demand for energy, and a corresponding rise in the combustion of carbon containing fossil fuels such as coal, petroleum, and natural gas. Undisputable scientific evidence indicates significant changes in the global climate have occurred in recent years. Impacts of climate change and the resulting atmospheric warming are extensive, and know no political or geographic boundaries. These far-reaching effects will be manifested as environmental, economic, socioeconomic, and geopolitical issues. Offsetting the projected increase in fossil energy use with renewable energy production will require large increases in renewable energy systems, as well as the ability to store and transport clean domestic fuels. Storage and transport of electricity generated from intermittent resources such as wind and solar is central to the widespread use of renewable energy technologies. Hydrogen created from water electrolysis is an option for energy storage and transport, and represents a pollution-free source of fuel when generated using renewable electricity. The conversion of chemical to electrical energy using fuel cells provides a high efficiency, carbon-free power source. Hydrogen serves to blur the line between stationary and mobile power applications, as it can be used as both a transportation fuel and for stationary electricity generation, with the possibility of a distributed generation energy infrastructure. Hydrogen and fuel cell technologies will be presented as possible pollution-free solutions to present and future energy concerns. Recent hydrogen-related research at SLAC in hydrogen production, fuel cell catalysis, and hydrogen storage will be highlighted in this seminar.

Leisch, Jennifer

2007-02-27

372

Hydrogen-enriched fuels  

Energy Technology Data Exchange (ETDEWEB)

NRG Technologies, Inc. is attempting to develop hardware and infrastructure that will allow mixtures of hydrogen and conventional fuels to become viable alternatives to conventional fuels alone. This commercialization can be successful if the authors are able to achieve exhaust emission levels of less than 0.03 g/kw-hr NOx and CO; and 0.15 g/kw-hr NMHC at full engine power without the use of exhaust catalysts. The major barriers to achieving these goals are that the lean burn regimes required to meet exhaust emissions goals reduce engine output substantially and tend to exhibit higher-than-normal total hydrocarbon emissions. Also, hydrogen addition to conventional fuels increases fuel cost, and reduces both vehicle range and engine output power. Maintaining low emissions during transient driving cycles has not been demonstrated. A three year test plan has been developed to perform the investigations into the issues described above. During this initial year of funding research has progressed in the following areas: (a) a cost effective single-cylinder research platform was constructed; (b) exhaust gas speciation was performed to characterize the nature of hydrocarbon emissions from hydrogen-enriched natural gas fuels; (c) three H{sub 2}/CH{sub 4} fuel compositions were analyzed using spark timing and equivalence ratio sweeping procedures and finally; (d) a full size pick-up truck platform was converted to run on HCNG fuels. The testing performed in year one of the three year plan represents a baseline from which to assess options for overcoming the stated barriers to success.

Roser, R. [NRG Technologies, Inc., Reno, NV (United States)

1998-08-01

373

Development of PEM fuel cell technology at international fuel cells  

Energy Technology Data Exchange (ETDEWEB)

The PEM technology has not developed to the level of phosphoric acid fuel cells. Several factors have held the technology development back such as high membrane cost, sensitivity of PEM fuel cells to low level of carbon monoxide impurities, the requirement to maintain full humidification of the cell, and the need to pressurize the fuel cell in order to achieve the performance targets. International Fuel Cells has identified a hydrogen fueled PEM fuel cell concept that leverages recent research advances to overcome major economic and technical obstacles.

Wheeler, D.J.

1996-04-01

374

Fuel cell system  

Science.gov (United States)

A fuel cell system is comprised of a fuel cell module including sub-stacks of series-connected fuel cells, the sub-stacks being held together in a stacked arrangement with cold plates of a cooling means located between the sub-stacks to function as electrical terminals. The anode and cathode terminals of the sub-stacks are connected in parallel by means of the coolant manifolds which electrically connect selected cold plates. The system may comprise a plurality of the fuel cell modules connected in series. The sub-stacks are designed to provide a voltage output equivalent to the desired voltage demand of a low voltage, high current DC load such as an electrolytic cell to be driven by the fuel cell system. This arrangement in conjunction with switching means can be used to drive a DC electrical load with a total voltage output selected to match that of the load being driven. This arrangement eliminates the need for expensive voltage regulation equipment.

Early, Jack (Perth Amboy, NJ); Kaufman, Arthur (West Orange, NJ); Stawsky, Alfred (Teaneck, NJ)

1982-01-01

375

Reactor fuel exchanging facility  

International Nuclear Information System (INIS)

Purpose: To enable operation of an emergency manual operating mechanism for a fuel exchanger with all operatorless trucks and remote operation of a manipulator even if the exchanger fails during the fuel exchanging operation. Constitution: When a fuel exchanging system fails while connected to a pressure tube of a nuclear reactor during a fuel exchanging operation, a stand-by self-travelling truck automatically runs along a guide line to the position corresponding to the stopping position at that time of the fuel exchanger based on a command from a central control chamber. At this time the truck is switched to manual operation, and approaches the exchanger while being monitored through a television camera and then stops. Then, a manipurator is connected to the emergency manual operating mechanism of the exchanger, and is operated through necessary emergency steps by driving the snout, the magazine, the grab or the like in the exchanger in response to the problem, and necessary operations for the emergency treatment are thus performed. (Sekiya, K.)

376

Fueling Global Fishing Fleets  

International Nuclear Information System (INIS)

Over the course of the 20th century, fossil fuels became the dominant energy input to most of the world's fisheries. Although various analyses have quantified fuel inputs to individual fisheries, to date, no attempt has been made to quantify the global scale and to map the distribution of fuel consumed by fisheries. By integrating data representing more than 250 fisheries from around the world with spatially resolved catch statistics for 2000, we calculate that globally, fisheries burned almost 50 billion L of fuel in the process of landing just over 80 million t of marine fish and invertebrates for an average rate of 620 L/t. Consequently, fisheries account for about 1.2% of global oil consumption, an amount equivalent to that burned by the Netherlands, the 18th-ranked oil consuming country globally, and directly emit more than 130 million t of CO2 into the atmosphere. From an efficiency perspective, the energy content of the fuel burned by global fisheries is 12.5 times greater than the edible protein energy content of the resulting catch

377

Nuclear fuel handling apparatus  

International Nuclear Information System (INIS)

A fuel handling machine for a liquid metal cooled nuclear reactor in which a retractable handling tube and gripper are lowered into the reactor to withdraw a spent fuel assembly into the handling tube. The handling tube containing the fuel assembly immersed in liquid sodium is then withdrawn completely from the reactor into the outer barrel of the handling machine. The machine is then used to transport the spent fuel assembly directly to a remotely located decay tank. The fuel handling machine includes a decay heat removal system which continuously removes heat from the interior of the handling tube and which is capable of operating at its full cooling capacity at all times. The handling tube is supported in the machine from an articulated joint which enables it to readily align itself with the correct position in the core. An emergency sodium supply is carried directly by the machine to provide make up in the event of a loss of sodium from the handling tube during transport to the decay tank. 5 claims, 32 drawing figures

378

Bio-fuels  

International Nuclear Information System (INIS)

This report presents an overview of the technologies which are currently used or presently developed for the production of bio-fuels in Europe and more particularly in France. After a brief history of this production since the beginning of the 20. century, the authors describe the support to agriculture and the influence of the Common Agricultural Policy, outline the influence of the present context of struggle against the greenhouse effect, and present the European legislative context. Data on the bio-fuels consumption in the European Union in 2006 are discussed. An overview of the evolution of the activity related to bio-fuels in France, indicating the locations of ethanol and bio-diesel production facilities, and the evolution of bio-fuel consumption, is given. The German situation is briefly presented. Production of ethanol by fermentation, the manufacturing of ETBE, the bio-diesel production from vegetable oils are discussed. Second generation bio-fuels are then presented (cellulose enzymatic processing), together with studies on thermochemical processes and available biomass resources

379

Metal fuel for reactor  

International Nuclear Information System (INIS)

The present invention concerns nuclear metal fuels suitable to FBR type reactors and the object of the invention is to prevent partial reduction of melting point due to the re-distribution of the ZR ingredient in the metal fuels comprising U-Pu-Zr system alloy or U-Zr system alloy. That is, at a radial intermediate portion in a radial cross section of a cylindrical metal fuel comprising U-Pu-Zr system alloy or U-Zr system, a region with higher Zr content than that in the U-Pu-Zr system alloy or U-Zr system alloy is disposed. In conventional metal fuels of this type, the content at the radial intermediate portion of the cylinder is reduced accompanying the advance of burning and re-distributed such that the content ratio between the central region and the outer circumferential region is increased. On the other hand, in the fuels having the feature of the present invention, the higher Zr content region constitutes a source for the Zr ingredient even if the re-distribution of the alloy ingredient occurs, thereby enabling to prevent the reduction of the Zr ingredient. (I.S.)

380

Fuel assemblies for surveillance  

International Nuclear Information System (INIS)

Purpose: To improve the thermal margin and increase the fast neutron irradiation dose to the irradiated test pieces in the capsule in the special fuel assembly for use in pressure tube type reactors. Constitution: The fuel assembly for use in survey lance according to this invention comprises a plurality of nuclear fuel rods, a capsule guide tube situated at the center thereof and a capsule entered therein, having coolant flow channels and incorporating pressure tube member monitoring pieces. Another capsule also having coolant channels and containing material with the thermal neutron absorption cross section being greater as compared with the structural material other than the nuclear fuels is disposed while put between the test piece incorporating capsules. In this way, the reactivity of the special fuel assembly is reduced, the thermal margin is increased and, simultaneously, thermo neutrons within the guide tube of the capsule are decreased, the ratio of the fast neutrons is increased relatively and, accordingly, the amount of the fission products is increased and the radiation amount of the fast neutron is increased. (Horiuchi, T.)

 
 
 
 
381

Fuel retention in tokamaks  

Science.gov (United States)

Tritium retention constitutes an outstanding problem for ITER operation and future fusion reactors, particularly for the choice of the first wall materials. In present day tokamaks, fuel retention is evaluated by two complementary methods. The in situ gas balance allows evaluation of how much fuel is retained during a discharge and, typically, up to one day of experiments. Post-mortem analysis is used to determine where the fuel is retained, integrated over an experimental campaign. In all the carbon clad devices, using the two methods, the retention is demonstrated to be very closely related to the carbon net erosion. This results from plasma-wall interaction with ion and charge-exchange fluxes, ELMs and is proportional to the pulse duration. The fuel retention by implantation saturates at high wall temperatures and limits the D/C ratio in the deposited layers but, as far as a carbon source exists, the dominant retention process remains the co-deposition of carbon with deuterium. In full metallic device, in the absence of wall conditioning with boron, co-deposition is strongly reduced and fuel retention below 1% can be achieved. Extrapolation to ITER shows that removing the carbon from the plasma-facing components would increase the number of discharges to 2500 before reaching the maximum tritium limit of 700 g.

Loarer, T.

2009-06-01

382

Fuel assembly box disposal  

International Nuclear Information System (INIS)

Approximately 1000 fuel assembly boxes had to be disposed of at the Philippsburg Nuclear Power Station by late 1992. The campaign was carried out in a three-shift operation together with GNS, the Technical Inspectorate (TUeV), and the authorities. Shielding calculations preceding the disposal activities were based on the lifetime data of the fuel assembly boxes and on dose rate measurements performed. The fuel assembly boxes were pulled out of their positions with the telescopic mast of the refueling machine. When it had been loaded with 66 fuel assembly boxes, the mosaic flask was closed, drained, and dried for approx. 20 hours. The flask was checked for contamination before it was transferred through locks out of the reactor building. The sequence of steps carried out in an assembly box disposal is largely analogous to that of fuel assembly removal, except for the fact that it does not impose any additional requirements on the power plant personnel. The aggregate collective dose amounted to 13.9 mSv. (orig.)

383

Apparatus for fuel replacement  

International Nuclear Information System (INIS)

Object: To support a telescope mast such that no deforming load is applied to it even during massive vibration, it is held fixed at the time of fuel replacement to permit satisfactory remote control operation by automatic operation. Structure: The body of the fuel replacement apparatus is provided with telescope mast fixing means comprising a slide base supported for reciprocal movement with respect to a telescope mast, an operating arm pivoted at the slide base, a wrist member mounted on the free end of the operating arm and an engagement member for restricting the slide base and operating arm at the time of loading and unloading the fuel. When loading and unloading the fuel, the slide base and operating arm are restrained by the engagement member to reliably restrict the vibration of the telescope mast. When the fuel replacement apparatus is moved, the means provided on the operating arm is smoothly displaced to follow the swing (vibration) of the telescope mast to prevent the deforming load from being applied to the support portion or other areas. The wrist member supports the telescope mast such that it can be rotated while restraining movement in the axial direction, and it is provided with revolution drive means for rotating the telescope mast under remote control. (Kamimura, M.)

384

Fuel retention in tokamaks  

International Nuclear Information System (INIS)

Tritium retention constitutes an outstanding problem for ITER operation and future fusion reactors, particularly for the choice of the first wall materials. In present day tokamaks, fuel retention is evaluated by two complementary methods. The in situ gas balance allows evaluation of how much fuel is retained during a discharge and, typically, up to one day of experiments. Post-mortem analysis is used to determine where the fuel is retained, integrated over an experimental campaign. In all the carbon clad devices, using the two methods, the retention is demonstrated to be very closely related to the carbon net erosion. This results from plasma-wall interaction with ion and charge-exchange fluxes, ELMs and is proportional to the pulse duration. The fuel retention by implantation saturates at high wall temperatures and limits the D/C ratio in the deposited layers but, as far as a carbon source exists, the dominant retention process remains the co-deposition of carbon with deuterium. In full metallic device, in the absence of wall conditioning with boron, co-deposition is strongly reduced and fuel retention below 1% can be achieved. Extrapolation to ITER shows that removing the carbon from the plasma-facing components would increase the number of discharges to 2500 before reaching the maximum tritium limit of 700 g.

385

Nuclear fuel assembly  

International Nuclear Information System (INIS)

Corner posts are disposed respectively to four corners of an upper tie plate. An end plug insertion hole is formed at the lower portion of each of the corner posts for arranging fuel rods. An extended portion prepared by extending the post in the direction of the central axis of a fuel assembly is disposed at the upper portion of at least one of the corner posts. Then, a screw hole is formed at the extended portion for fixing a channel box and a channel fastener. With such a constitution, even when the length of the corner post is shortened, there is no worry that an end plug insertion hole and the screw hole overlap to each other. Accordingly, even when a fuel rod is extended by burning, the upper end plug of the fuel rod and the fixing screw of the screw hole do not interfere with each other. As a result, a long fuel rod for high burnup degree having increased plenum volume can be used integrally. (I.N.)

386

Diagnosis device for fuel assemblies  

International Nuclear Information System (INIS)

Purpose: To detect the symptoms of fuel rod failures in fuel assemblies to thereby prevent fuel rod failures in fuel assemblies for use in BWR type reactors. Constitution: Upon shutdown of the reactor operation, difference in the axial elongation between a fuel rod and a water rod is determined. Then, the soundness of the fuel assembly is judged based on the relationship between the difference of the previously set axial elongation and the index for the fuel rod failure. Since the symptoms of the failure can thus be detected by determining the index for the fuel rod failure in a non-destructive manner, fuel rod failure can be prevented to improve the burnup degree. (Moriyama, K.)

387

Factors controlling metal fuel lifetime  

International Nuclear Information System (INIS)

The reliability of metal fuel elements is determined by a fuel burnup at which a statistically predicted number of fuel breaches would occur, the number of breaches determined by the amount of free fission gas which a particular reactor design can tolerate. The reliability is therefore measured using experimentally determined breach statistics, or by modelling fuel element behavior and those factors which contribute to cladding breach. The factors are fuel/cladding mechanical and chemical interactions, fission gas pressure, fuel phase transformations involving volume changes, and fission product effects on cladding integrity. Experimental data for EBR-II fuel elements has shown that the primary, and perhaps the only significant factor affecting metal fuel reliability, is the pressure-induced stresses caused by fission gas release. Other metal fuel/cladding systems may perform similarly

388

Dry Process Fuel Performance Evaluation  

International Nuclear Information System (INIS)

The objective of the project is to establish the performance evaluation system of DUPIC fuel during the Phase II R and D. In order to fulfil this objectives, irradiation test of DUPIC fuel was carried out in HANARO using the non-instrumented and SPND-instrumented rig. Also, the analysis on the in-reactor behavior analysis of DUPIC fuel, out-pile test using simulated DUPIC fuel as well as performance and integrity assessment in a commercial reactor were performed during this Phase. The R and D results of the Phase II are summarized as follows : - Performance evaluation of DUPIC fuel via irradiation test in HANARO - Post irradiation examination of irradiated fuel and performance analysis - Development of DUPIC fuel performance code (modified ELESTRES) considering material properties of DUPIC fuel - Irradiation behavior and integrity assessment under the design power envelope of DUPIC fuel - Foundamental technology development of thermal/mechanical performance evaluation using ANSYS (FEM package)

389

Integrated Pilot Plant for a Large Cold Crucible Induction Melter  

International Nuclear Information System (INIS)

l stirring of the melter significantly reduces operating constraints. COGEMA is already providing the CCM technology to international customers for nuclear and non-nuclear applications and plans to implement it in the La Hague vitrification plant for the vitrification of highly concentrated and corrosive solutions produced by uranium/molybdenum fuel reprocessing. The paper presents the CCM project that led to the building and start-up of this evolutionary and flexible pilot plant. It also describes the plant's technical characteristics and reports commissioning results

390

RERTR-12 Insertion 2 Irradiation Summary Report  

Energy Technology Data Exchange (ETDEWEB)

The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-12 was designed to provide comprehensive information on the performance of uranium-molybdenum (U-Mo) based monolithic fuels for research reactor applications.1 RERTR-12 insertion 2 includes the capsules irradiated during the last three irradiation cycles. These capsules include Z, Y1, Y2 and Y3 type capsules. The following report summarizes the life of the RERTR-12 insertion 2 experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.

D. M. Perez; G. S. Chang; D. M. Wachs; G. A. Roth; N. E. Woolstenhulme

2012-09-01

391

HTGR spent fuel composition and fuel element block flow  

International Nuclear Information System (INIS)

The High-Temperature Gas-Cooled Reactor (HTGR) utilizes the thorium-uranium fuel cycle. Fully enriches uranium fissile material and thorium fertile material are used in the initial reactor core and for makeup fuel in the recycle core loadings. Bred 233U and unburned 235U fissile materials are recovered from spent fuel elements, refabricated into recycle fuel elements, and used as part of the recycle core loading along with the makeup fuel elements. A typical HTGR employs a 4-yr fuel cycle with approximately one-fourth of the core discharged and reloaded annually. The fuel element composition, including heavy metals, impurity nuclides, fission products, and activation products, has been calculated for discharged spent fuel elements and for reload fresh fuel and recycle fuel elements for each cycle over the life of a typical HTGR. Fuel element compositions are presented for the conditions of equilibrium recycle. Data describing compositions for individual reloads throughout the reactor life are available in a detailed volume upon request. Fuel element block flow data have been compiled based on a forecast HTGR market. Annual block flows are presented for each type of fuel element discharged from the reactors for reprocessing and for refabrication

392

Development of fuel service technology  

International Nuclear Information System (INIS)

Related PWR nuclear fuel, strategy and scope of work of the nuclear fuel service technology should be established to develope nuclear fuel service technology and related equipments and tools so as to provide sound PWR nuclear fuel and increase nuclear power plants safety and operability. At present situation, our own PWR nuclear fuel service technology should be established through understanding induced foreign technology transferred along with PWR Fuel Technology Transfer. As a basic research project to establish the strategy and scope of work for the PWR Fuel Service Technology Development, technical informations of foreign technology have been reviewed and strategy and scope of work of the fuel performance inspection and measuring technology and repair equipment design and manufacturing have been studied. In order to preserve safe and economical operation of power plants, mechanical integrity of the nuclear fuel should be insured. Therefore, establishment of nuclear fuel service technology and equipment engineering is the most important supplementary technology. In order to delineate the strategy of nuclear fuel service technology development and clarity our technical position in this special field, related technologies of foreign nuclear fuel technology partners and that of in Korea have been analyzed and compared. Design characteristics of various fuel in operation has neen studied to provide the direction of conceptional design of poolside inspection and measurement equipments as well as damaged fuel repair equipments. Fuel failure mechanisms which have occured in several nuclear power plants have been studied to provide valuable information to improve fuel design, fabrication technology and plant operation condition. Status of reactor coolant activity analysis technique on operating reactors was evaluated for the development of inpile fuel integrity analysis technology. Conceptional design of poolside inspection/measurement equipment and damaged fuel repair equipments was performed to establish strategy in equipment localization. (Author)

393

Spent fuel pyroprocessing demonstration  

International Nuclear Information System (INIS)

A major element of the shutdown of the US liquid metal reactor development program is managing the sodium-bonded spent metallic fuel from the Experimental Breeder Reactor-II to meet US environmental laws. Argonne National Laboratory has refurbished and equipped an existing hot cell facility for treating the spent fuel by a high-temperature electrochemical process commonly called pyroprocessing. Four products will be produced for storage and disposal. Two high-level waste forms will be produced and qualified for disposal of the fission and activation products. Uranium and transuranium alloys will be produced for storage pending a decision by the US Department of Energy on the fate of its plutonium and enriched uranium. Together these activities will demonstrate a unique electrochemical treatment technology for spent nuclear fuel. This technology potentially has significant economic and technical advantages over either conventional reprocessing or direct disposal as a high-level waste option

394

Advanced development: Fuels  

Science.gov (United States)

The solar thermal fuels and chemicals program at Jet Propulsion Laboratory are described. High technology is developed and applied to displace fossil fuel (oil) use in the production/processing of valuable fuels and chemicals. The technical and economic feasibility is demonstrated to extent that enables the industry to participate and commercialize the product. A representative process, namely Furfural production with a bottoming of acetone, butanol and ethanol, is described. Experimental data from all solar production of furfural is discussed. Estimates are given to show the attractiveness of this process, considering its flexibility to be adaptable to dishes, troughs or central receivers. Peat, lignite and low rank coal processing, heavy oil stripping and innovative technologies for process diagnostics and control are mentioned as examples of current projects under intensive development.

Ramohalli, K.

1981-05-01

395

Fuel Element Technical Manual  

Energy Technology Data Exchange (ETDEWEB)

It is the purpose of the Fuel Element Technical Manual to Provide a single document describing the fabrication processes used in the manufacture of the fuel element as well as the technical bases for these processes. The manual will be instrumental in the indoctrination of personnel new to the field and will provide a single data reference for all personnel involved in the design or manufacture of the fuel element. The material contained in this manual was assembled by members of the Engineering Department and the Manufacturing Department at the Hanford Atomic Products Operation between the dates October, 1955 and June, 1956. Arrangement of the manual. The manual is divided into six parts: Part I--introduction; Part II--technical bases; Part III--process; Part IV--plant and equipment; Part V--process control and improvement; and VI--safety.

Burley, H.H. [ed.

1956-08-01

396

Fuel cells in transportation  

Energy Technology Data Exchange (ETDEWEB)

A promising new power source for electric drive systems is the fuel cell technology with hydrogen as energy input. The worldwide fuel cell development concentrates on basic research efforts aiming at improving this new technology and at developing applications that might reach market maturity in the very near future. Due to the progress achieved, the interest is now steadily turning to the development of overall systems such as demonstration plants for different purposes: electricity generation, drive systems for road vehicles, ships and railroads. This paper does not present results concerning the market potential of fuel cells in transportation but rather addresses some questions and reflections that are subject to further research of both engineers and economists. Some joint effort of this research will be conducted under the umbrella of the IEA Implementing Agreement 026 - Annex X, but there is a lot more to be done in this challenging but also promising fields. (EG) 18 refs.

Erdmann, G. [Technische Univ., Berlin (Germany); Hoehlein, B. [Research Center Juelich (Germany)

1996-12-01

397

Fuel-coolant interactions  

International Nuclear Information System (INIS)

An important aspect of nuclear fuel behaviour that impacts on the fuel cycle is the interaction of the cladding with the coolant. In particular, the accumulation of deposited crud (corrosion products transported in the reactor coolant) on fuel element surfaces can severely hamper fuel performance by impeding heat transfer and promoting cladding corrosion, both of which may lead to fuel defects and the release of fission products and actinides to the primary coolant systems. Crud deposition is therefore an important consideration in reactor operation; it not only leads to poor performance and radiation field growth by exacerbating fuel defects but also serves as the source of radionuclides such as Co-60 which are major contaminants of out-reactor components. Furthermore, the sequestering of boron from the coolant by fuel deposits in PWRs can give rise to control problems as reactor flux characteristics are modified. As utilities apply the ALARA principle (As Low As Reasonably) to the management of occupational radiation doses and at the same time endeavour to optimise the fuel cycle, it becomes clear that an understanding of the mechanisms involved in coolant-cladding interactions is vital. There are several mechanisms of interest here. The source of crud is the fundamental corrosion process accruing on surfaces of the coolant system and the interaction of that process with local regimes of coolant flow. Accordingly, differences in the chemical and physical condition of the coolant across the reactor core and the steam generators are important factors in CANDUs and PWRs determining release of corrosion products from surfaces, while similar processes along the feedtrain influence crud levels in the reactor coolant in BWRs. The nature of suspended crud, which is determined by the materials of construction of the various components of the coolant system and the chemistry control of the coolant itself, determines the interaction with fuel cladding. Thus, crud in CANDUs is dominated by iron oxide (magnetite Fe3O4) because of the large proportion of carbon steel in the circuit, while in PWRs crud is an iron-nickel oxide (nickel ferrite - NiFe2O4 or a variant) because of the presence of stainless steel and nickel alloys. The more oxidizing nature of BWR coolant causes a higher phase of iron oxide to occur, so that haematite (Fe2O3) becomes a constituent of deposits in BWRs. The deposition of the suspended crud of fuel surfaces is influenced by the electrostatic charge on the particles themselves and on the fuel surface. The chemistry regime-oxidizing nature, alkalinity, boron concentration, etc.-determines those surface charges. The forces arising from the thermalhydraulic conditions in the core and the physical properties of the crud (such as particle size) then interact with the surface forces to determine the deposition characteristics. Besides the deposition of suspended material, the deposition of corrosion products from solution can occur and in fact may dominate in CANDUs and PWRs where the solubility of oxides relatively high. In that case, it is important to tailor the coolant chemistry to minimize the solubility and to ensure that the change of solubility with temperature is not such as to promote massive precipitation in the core. Even then, adsorption-desorption at fuel surfaces of ions such as Co2+ will lead to a level of system activation that depends on the indigenous corrosion film on the cladding surface

398

Advanced fuel cell development  

Science.gov (United States)

Fuel cell research and development activities at Argonne National Laboratory (ANL) during the period July through September 1984 are discussed. These efforts were directed toward seeking alternative cathode materials to NiO for molten carbonate fuel cells. Particular emphasis was placed on studying the relationship of synthesis and sintering conditions on the resistivity of doped and undoped LiFeO2 and Li2MnO3 and on achieving a better understanding of the crystalline defect structures of phases that are thermodynamically stable at 1- and 10-atm pressure. To this end, several experimental assemblies (including synthesis, solubility, and sintering vessels and a high-pressure thermogravimetric analyzer) were constructed to permit 10-atm operation. Methods to improve the corrosion resistance of stainless steel components in ion-migration test cells are under assessment. A study to provide improved understanding of anode creep and densification occuring under fuel cell conditions is under way.

Pierce, R. D.; Minh, N. Q.; Smith, J. L.; Kucera, G. H.; Mrazek, F. C.; Stapay, J. R.; Moreschi, J.; Herceq, R.; Poeppel, R. B.; Routhort, J.

1985-06-01

399

Nuclear fuel pellet  

International Nuclear Information System (INIS)

Nuclear fuel pellets are prepared by mixing one or plural kinds of oxide fuel material powders such as UO2, or other uranium oxides and plutonium oxides, applying integral compression molding and sintering. The composition of the starting materials is adjusted to define the crystal grain size in the radial center increased to greater than 20? m and that in the outer circumference to smaller than 10? m. Further, the radial thickness of the outer circumference is determined to 1 to 10% of the diameter of the pellet. Accordingly, the radial centeral portion is constituted with a texture of large crystal grain size of excellent retainability for gaseous fission products (FP gases). On the other hand, the outer circumferencial portion is constituted with a tissure of small crystal grain size with a relatively great creeping rate. With such a constitution, a FP gas releasing rate can be decreased without increasing the fuel-cladding interaction upon irradiation. (I.N.)

400

Who's fueling whom  

International Nuclear Information System (INIS)

The costs of government subsidies to the nuclear industry have only recently been calculated in terms of the favorable economics of nuclear power plants relative to fossl-fuel plants. Subsidies in the form of research and development funding were expected to lead to a private nuclear power industry, but the private sector failed to respond until the Price-Anderson Act was passed to limit their liability. The uranium suppliers were subsidized through military purchases and import restrictions and through the formation of power pools to encourage power plant construction. Waste disposal and plant decommissioning will raise the back-end costs, which will require new subsidies. A determination of the true costs of producing electric power, with each fuel accounting for its full costs, would reveal significant subsidies to various fuels and could indicate the cost-effectiveness of some alternative energy sources

 
 
 
 
401

Hanaro fuel gamma scanning  

International Nuclear Information System (INIS)

One bundle of Hanaro fuel irradiated up to 50%-burnup and cooled for 6 months was transported to IMEF for PIE, which has 6 elements. At first we measured the longitudinal distribution and the rotational distribution of several dominant peaks intensities from the bundle. After dismantling of the bundle we measured the longitudinal distribution of 137Cs and 134Cs peaks in each fuel element to see the burn-up feature. And finally we found out the relative number distribution of 137Cs and 134Cs for each detection point, which would be used for burn-up calculation. The relative detection efficiency of the scanning system was obtained experimentally by using the 134Cs peaks. We also checked up the azimuthal difference of peak intensity for each element, which are resulted about 2% of difference. These data will be used for the further analysis of Hanaro fuel performance evaluation. (author)

402

Hanaro fuel gamma scanning  

Energy Technology Data Exchange (ETDEWEB)

One bundle of Hanaro fuel irradiated up to 50%-burnup and cooled for 6 months was transported to IMEF for PIE, which has 6 elements. At first we measured the longitudinal distribution and the rotational distribution of several dominant peaks intensities from the bundle. After dismantling of the bundle we measured the longitudinal distribution of {sup 137}Cs and {sup 134}Cs peaks in each fuel element to see the burn-up feature. And finally we found out the relative number distribution of {sup 137}Cs and {sup 134}Cs for each detection point, which would be used for burn-up calculation. The relative detection efficiency of the scanning system was obtained experimentally by using the {sup 134}Cs peaks. We also checked up the azimuthal difference of peak intensity for each element, which are resulted about 2% of difference. These data will be used for the further analysis of Hanaro fuel performance evaluation. (author)

Hong, Kwon-Pyo; Kim, Tae-Yon; Park, Dae-Gyu; Koo, Dae-Seo; Kim, Bong-Goo [Korea Atomic Energy Research Institute, Taejon (Korea)

1999-09-01

403

Spent fuel pyroprocessing demonstration  

Energy Technology Data Exchange (ETDEWEB)

A major element of the shutdown of the US liquid metal reactor development program is managing the sodium-bonded spent metallic fuel from the Experimental Breeder Reactor-II to meet US environmental laws. Argonne National Laboratory has refurbished and equipped an existing hot cell facility for treating the spent fuel by a high-temperature electrochemical process commonly called pyroprocessing. Four products will be produced for storage and disposal. Two high-level waste forms will be produced and qualified for disposal of the fission and activation products. Uranium and transuranium alloys will be produced for storage pending a decision by the US Department of Energy on the fate of its plutonium and enriched uranium. Together these activities will demonstrate a unique electrochemical treatment technology for spent nuclear fuel. This technology potentially has significant economic and technical advantages over either conventional reprocessing or direct disposal as a high-level waste option.

McFarlane, L.F.; Lineberry, M.J.

1995-05-01

404

PWR type fuel assembly  

International Nuclear Information System (INIS)

In the fuel assembly of the present invention, upper and lower nozzle portions are reinforced to improve reliability of each of the nozzles. Namely, a PWR type fuel assembly comprises a large number of fuel rods and thimble tubes bundled by a plurality of indication lattices, and the upper and lower nozzles are secured respectively to the upper and lower ends of the thimble tube. In this case, at least either one of the upper and lower nozzles is formed into an integrated shape with no welding structure. With such a constitution, an enclosure and an adaptor plate are integrated to the upper nozzle, and a lower nozzle plate and legs are integrated to the lower nozzle respectively. As a result, strength is enhanced, and welding defects dose not occur since welding portions are eliminated. Accordingly, the reliability of each nozzle can be improved. (I.S.)

405

GENUSA Fuel Evolution  

International Nuclear Information System (INIS)

fuel performance behavior, and has been instrumental in the identification and characterization of each encountered failure mechanism. With the knowledge gained from this extensive experience base, mitigating actions have been developed and progressively implemented by GENUSA as part of a continuous program toward improved fuel reliability and performance. GENUSA's evolutionary product introduction strategy has been extremely successful. There has been a continuous stream of new products/processes that were developed to deliver improved performance. Relative to the 8x8 fuel operated in the 1980's, today's designs provide ?25% more efficiency and power capability and twice as much energy. Because of GENUSA's evolutionary design commitment, these product improvements have been successfully rolled out to our customers with no design or fabrication-related performance surprises. Additionally, this has been accomplished with an accompanying steady improvement in fuel reliability. In the past three decades, fuel reliability has improved by approximately three orders of magnitude. That is, the fuel rod leaker rate has been reduced from over five hundred rods per million operating, to less than ten. In past decades, most plants experienced failures each cycle, and fleet-wide failure mechanisms drove reliability statistics. Today, a small minority of our customers' plants experience failures in any cycle, mainly recurrent, low level debris fretting failures in a handful of plants. GENUSA is committed to providing the most robust, and balanced, fuel solutions to our customers based on our extensive experience and technological capabilities. Identifying and successfully mitigating the mechanisms that cause fuel failures has been instrumental in this observed improvement in fuel reliability. GENUSA systematically identified and eliminated mechanisms leading to failure through pool-side and hot cell examinations, and feedback of lessons learned into the design and fabrication of the fuel. Some of the highly successful mitigating actions during this history include: - Improved pellet fabrication in the 1970's to eliminate cladding primary hydride failures; - Corrosion-resistant cladding, with a chemistry and microstructure specifically targeted to protect against crud-induced corrosion (CILC) failures; - Improved cladding and welding fabrication and inspection techniques that assured the hermeticity and quality of the delivered fuel rod; - Tightened pellet missing surface specifications to add PCI margin; - Introduction of a debris filter, applied as a standard feature to 10x10 GE14, and as an optional feature in 9x9 fuel, to address debris fretting, as well as advancements to debris filters to achieve even better resistance to debris ingress. GENUSA has always taken the necessary steps to assure the infrastructure and technology are in place to support each product or potential product introduction program. This paper will describe these steps and the evolution of the GENUSA delivered product in Europe starting with the first Garona reload product and finish with a slight description of how our latest product, GNF2, was born. This will include how GENUSA opened to the European market and all the different products that GENUSA has offered and offers nowadays. (authors)

406

Fuel assemblies chemical cleaning  

Energy Technology Data Exchange (ETDEWEB)

NPP Paks found a thermal-hydraulic anomaly in the reactor core during cycle 14 that was caused by corrosion product deposits on fuel assemblies (FAs) that increased the hydraulic resistance of the FAs. Consequently, the coolant flow through the FAs was insufficient resulting in a temperature asymmetry inside the reactor core. Based on this fact NPP Paks performed differential pressure measurements of all fuel assemblies in order to determine the hydraulic resistance and subsequently the limit values for the hydraulic acceptance of FAs to be used. Based on the hydraulic investigations a total number of 170 FAs was selected for cleaning. The necessity for cleaning the FAs was explained by the fact that the FAs were subjected to a short term usage in the reactor core only maximum of 1,5 years and had still a capacity for additional 2 fuel cycles. (authors)

Schunk, J.; Beier, M.; Kovacs, F.; Mico, S.; Tilky, P. [Paks NPP (Hungary); Berthold, H.O.; Janzik, I.; Marquardt, G. [Framatome ANP GmbH (Germany)

2002-07-01

407

Nuclear fuel element  

International Nuclear Information System (INIS)

A nuclear fuel-containing body for a high temperature gas cooled nuclear reactor is described which comprises a flat plate in which the nuclear fuel is contained as a dispersion of fission product-retaining coated fuel particles in a flat sheet of graphitic or carbonaceous matrix material. The flat sheet is clad with a relatively thin layer of unfuelled graphite bonded to the sheet by being formed initially from a number of separate preformed graphitic artefacts and then platen-pressed on to the exterior surfaces of the flat sheet, both the matrix material and the artefacts being in a green state, to enclose the sheet. A number of such flat plates are supported edge-on to the coolant flow in the bore of a tube made of neutron moderating material. Where a number of tiers of plates are superimposed on one another, the abutting edges are chamfered to reduce vibration. (author)

408

Compact fuel cell  

Science.gov (United States)

A novel electrochemical cell which may be a solid oxide fuel cell (SOFC) is disclosed where the cathodes (144, 140) may be exposed to the air and open to the ambient atmosphere without further housing. Current collector (145) extends through a first cathode on one side of a unit and over the unit through the cathode on the other side of the unit and is in electrical contact via lead (146) with housing unit (122 and 124). Electrical insulator (170) prevents electrical contact between two units. Fuel inlet manifold (134) allows fuel to communicate with internal space (138) between the anodes (154 and 156). Electrically insulating members (164 and 166) prevent the current collector from being in electrical contact with the anode.

Jacobson, Craig (Moraga, CA); DeJonghe, Lutgard C. (Lafayette, CA); Lu, Chun (Richland, WA)

2010-10-19

409

Nuclear fuel rod  

International Nuclear Information System (INIS)

The invention deals with an improvement on the getter in a fuel rod of a nuclear reactor fuel element. These types of getters of zirconium or zirconium alloys inside the fuel rod cladding tend to form zirconium oxide coatings which reduce their effectiveness. The invention thus suggests to use a compound body acting as bimetal as getter which consists of a metal substrate and coating, where the substrate has a thermal expansion coefficient which is that much larger that the surface of the coating cracks time and again at operational temperature. According to the invention, the substrate may consist of nickel, a Ni alloy, a ferro-alloy, steel titanium, or titanium alloys. Zirconium or zirconium alloys are given as coating material. (RW)

410

Composite fuel cans for nuclear fuels  

International Nuclear Information System (INIS)

Purpose: To suppress corrosions at the inner surface of fuel cans in high temperature steams and absorption of hydrogen evolved upon corrosion to substrate material. Constitution: The composite fuel can comprises an outer tube made of a zirconium alloy material for the substrate and an inner tube prepared by metallurgically bonding an alloy material mainly composed of zirconium different from that for the substrate. The material for the inner tube comprises (i) 0.05 - 0.20 wt% iron, 0.05 - 0.5 wt% vanadium and the balance of zirconium, (ii) 0.05 - 0.20 wt% iron, 0.05 - 0.5 wt% antimony and the balance of zirconium (Zr), etc. By adding at least one Fe, V and Sb to Zr, corrosion resistance and hydrogen absorption property of the inner tube can be improved. The radial thickness of the inner tube is so constituted that it lies within a range from 3 to 15 % of the radial wall thickness of the entire composite tube. (Takahashi, M.)

411

Device for locating defective fuel  

International Nuclear Information System (INIS)

A method and apparatus for locating defective nuclear fuel elements is disclosed. Fuel elements that are to be tested are enclosed in a test chamber, filled with water. Air is pumped or pulled into the chamber, entering through a gas sparger at the bottom of the chamber and displacing a portion of the water above the fuel element. This reduces the pressure in the vessel, forms an air pocket above the fuel element and purges the water surrounding the fuel element of fission gases released from defective fuel elements. The activity of sample gas drawn from the chamber is continuously monitored to indicate fission gas content

412

Fuel assembly configuration image analyzer  

International Nuclear Information System (INIS)

Neutron irradiation inside an operating nuclear reactor changes the dimensions of the reactor fuel assembly and its components. For example, irradiation can lengthen the fuel assembly and fuel rods, and change the gap between fuel rods. Mitsubishi Heavy Industries, Ltd. and Mitsubishi Nuclear Fuel Co., Ltd. have jointly developed a new, computer-assisted system to measure such changes. Using this system, a fuel assembly can be videotaped with underwater cameras and its dimensions precisely analyzed through efficient processing and automatic measurement of the video images. (author)

413

Fast reactor fuel fabrication development  

International Nuclear Information System (INIS)

Fabricating fuel for commercial LMFBRs demands a move to remote fabrication techniques to meet more restrictive personnel radiation exposure standards. There is thus an emphasis on process and plant selection which minimizes maintenance and leads to ease of decontamination. The wet gel process route (in which plant vessels provide primary containment) for production of spherical fuel particles for subsequent fuel fabrication using the vibro-compaction technique meets these criteria. U.K. experience with this process and its impact on the fuel cycle is described. Extension of the technology to produce oxide fuel pellets and carbide fuel is discussed. (U.K.)

414

The fuel cycle scoping system  

International Nuclear Information System (INIS)

The Fuel Cycle Scoping System (FCSS) was created to fill the need for a scoping tool which provides the utilities with the ability to quickly evaluate alternative fuel management strategies, tails assay choices, fuel fabrication quotes, fuel financing alternatives, fuel cycle schedules, and other fuel cycle perturbations. The FCSS was specifically designed for PC's that support dBASE-III(TM), a relational data base software system by Ashton-Tate. However, knowledge of dBASE-III is not necessary in order to utilize the FCSS. The FCSS is menu driven and can be utilized as a teaching tool as well as a scoping tool

415

Improved PWR fuel cladding  

International Nuclear Information System (INIS)

Observations of irradiation-enhanced corrosion of PWR fuel at higher exposures has necessitated the development of improved cladding alloys through alloy modification of Zircaloy-4 within the specification limits, and through the formulation of alternate alloy compositions. The ZIRLOTM composition, Zr-1.0Nb-1.0Sn-0.1Fe, was developed as a superior corrosion resistant material for use in high-burnup fuel. The selection of alloying constituents and processing approach was based upon extensive laboratory data on the corrosion behavior of various Zr-Nb and Zr-Nb-Sn alloys, coupled with favorable data reported for Zr-2.5Nb, and the reported resistance to irradiation enhanced corrosion of a Zr-1Nb-1Sn-0.5Fe alloy in an oxygenated boiling water loop. Thus, fuel tubes of several Zr-Nb binary alloys containing up to 2.5% Nb, and of the ZIRLO composition, were fabricated with particular attention to achieving a fine size and uniform distribution of second phase particles. Fuel rods of these alloys were inserted into the BR-3 reactor and achieved rod average burnups of up to 71 GWD/MTU during four cycles of operation. ZIRLO cladding displayed corrosion improvement of up to 50%, lower creep, and lower growth than the Zircaloy-4 cladding. Nodular corrosion was observed on the 1.0 and 2.5 Nb binary alloys, but was not present on the ZIRLO rods. ZIRLO was selected as the preferred cladding for high-burnup fuel. The results of one-cycle exposure in demonstration assemblies in a high-rated commercial PWR confirm the improved corrosion resistance of ZIRLO over Zircaloy-4. A full region of ZIRLO-clad fuel is planned for insertion in another PWR later in 1991. (author). 15 refs, 13 figs, 1 tab

416

Transfer of fuel assemblies  

International Nuclear Information System (INIS)

Fuel assemblies of a nuclear reactor are transferred during fueling or refueling or the like by a crane. The work-engaging fixture of the crane picks up an assembly, removes it from this slot, transfers it to the deposit site and deposits it in its slot at the deposit site. The control for the crane includes a strain gauge connected to the crane line which raises and lowers the load. The strain gauge senses the load on the crane. The signal from the strain gauge is compared with setpoints; a high-level setpoint, a low-level setpoint and a slack-line setpoint. If the strain gauge signal exceeds the high-level setpoint, the line drive is disabled. This event may occur during raising of a fuel assembly which encounters resistance. The high-level setpoint may be overridden under proper precautions. The line drive is also disabled if the strain gauge signal is less than the low-level setpoint. This event occurs when a fuel assembly being deposited contacts the bottom of its slot or an obstruction in, or at the entry to the slot. To preclude lateral movement and possible damage to a fuel assembly suspended from the crane line, the traverse drive of the crane is disabled once the strain-gauge exceets the lov-level setpoint. The traverse drive can only be enabled after the strain-gauge signal is less than the slack-line set-point. This occurs when the lines has been set in slack-line setting. When the line is tensioned after slack-li ne setting, the traverse drive remains enane setting, the traverse drive remains enabled only if the line has been disconnected from the fuel assembly

417

Nuclear fuel cladding tubes  

International Nuclear Information System (INIS)

Purpose: To maintain the poisoning effect for a required period of time and moderate the stresses due to the fuel-cladding interactions in cladding tubes for gadolinium oxide-containing UO2 fuels. Constitution: The cladding tube is made of a zirconium alloy. A metal or alloy compatible with and softer than the zirconium alloy is lined to the inner surface of the tube. Further, the lined layer is incorporated with burnable poisons selected from the group consisting of Cd, Sm, Dy, Du and B. (Ikeda, J.)

418

Linseed as renewable fuel  

International Nuclear Information System (INIS)

The cultivation of renewable fuels is a way of reducing excess food production and of opening up alternatives of labour and income on the agricultural sector. Industry takes an interest in renewable fuels because of the ecological aspect. Vegetable oils may be used as lubricants (e.g. for chainsaws, hydraulic systems and two-stroke engines), while starck may be utilized as biodegradable packaging material. The report therefore investigates the chances for linseed production in Germany. The economic efficiency of linseed production may be improved by utilizing the slow-degradable linseed stran as mulding material in gardening and landscaping and for erosion protection. (orig.)

419

Bioethanol: fuel or feedstock?  

DEFF Research Database (Denmark)

Increasing amounts of bioethanol are being produced from fermentation of biomass, mainly to counteract the continuing depletion of fossil resources and the consequential escalation of oil prices. Today, bioethanol is mainly utilized as a fuel or fuel additive in motor vehicles, but it could also be used as a versatile feedstock in the chemical industry. Currently the production of carbon-containing commodity chemicals is dependent on fossil resources, and more than 95% of these chemicals are produced from non-renewable carbon resources. The question is: what will be the optimal use of bioethanol in a longer perspective? (c) 2007 Society of Chemical Industry.

Rass-Hansen, Jeppe; Falsig, Hanne

2007-01-01

420

Efficient multicomponent fuel algorithm  

Science.gov (United States)

We derive equations for multicomponent fuel evaporation in airborne fuel droplets and wall films, and implement the model into KIVA-3V. Temporal and spatial variations in liquid droplet composition and temperature are not modelled but solved for by discretizing the interior of the droplet in an implicit and computationally efficient way. We find that an interior discretization is necessary to correctly compute the evolution of the droplet composition. The details of the one-dimensional numerical algorithm are described. Numerical simulations of multicomponent evaporation are performed for single droplets and compared to experimental data.

Torres, D. J.; O'Rourke, P. J.; Amsden, A. A.

2003-03-01

 
 
 
 
421

Nuclear reactor fuel element  

Science.gov (United States)

A nuclear reactor fuel element is described which has an outer cladding, a central core of fissionable or mixed fissionable and fertile fuel material and a layer of oxygen gettering material on the inner surface of the cladding. The gettering material reacts with oxygen released by the fissionable material during irradiation of the core thereby preventing the oxygen from reacting with and corroding the cladding. Also described is an improved method for coating the inner surface of the cladding with a layer of gettering material.

Johnson, Carl E. (Elk Grove, IL); Crouthamel, Carl E. (Richland, WA)

1980-01-01

422

Fuel mixture. Kraftstoffgemisch  

Energy Technology Data Exchange (ETDEWEB)

Fuel mixture with a larger quantity of a fuel for Otto engines and a smaller quantity of an alkali metal salt or alkaline-earth metal salt of a derivative of the succinic acid which shows an unsubstituted or substituted aliphatic hydrocarbon residue as a substituent at least at one of its alpha carbon atoms with 20 to 200 carbon atoms or it shows such an unsubstituted or substituted hydrocarbon residue which is bound to the other alpha carbon atom by means of a hydrocarbon fraction with 1 or 6 carbon atoms. (orig.).

Es, C. van; Miles, R.; Kalghatgi, G.T.; McArragher, J.S.; Heldeweg, R.F.

1987-01-02

423

Nuclear fuel assembly  

International Nuclear Information System (INIS)

The nuclear fuel assembly described includes a cluster of fuel elements supported at a distance from each other so that their axes are parallel in order to establish secondary channels between them reserved for the coolant. Several ducts for an auxiliary cooling fluid are arranged in the cluster. The wall of each duct is pierced with coolant ejection holes which are placed circumferentially to a pre-determined pattern established according to the position of the duct in the cluster and by the axial distance of the ejection hole along the duct. This assembly is intended for reactors cooled by light or heavy water

424

Nuclear reactor fuel rod  

International Nuclear Information System (INIS)

The fuel rod consists of a can with at least one end cap and a plenum spring between this cap and the fuel. To prevent the hazard that a eutectic mixture is formed during welding of the end cap, a thermal insulation is added between the end cap and plenum spring. It consists of a comical extension of the end cap with a terminal disc against which the spring is supported. The end cap, the extension, and the disc may be formed by one or several pieces. If the disc is separated from the other parts it may be manufactured from chrome steel or VA steel. (DG)

425

Alternate fusion fuels workshop  

International Nuclear Information System (INIS)

The workshop was organized to focus on a specific confinement scheme: the tokamak. The workshop was divided into two parts: systems and physics. The topics discussed in the systems session were narrowly focused on systems and engineering considerations in the tokamak geometry. The workshop participants reviewed the status of system studies, trade-offs between d-t and d-d based reactors and engineering problems associated with the design of a high-temperature, high-field reactor utilizing advanced fuels. In the physics session issues were discussed dealing with high-beta stability, synchrotron losses and transport in alternate fuel systems. The agenda for the workshop is attached

426

Nuclear Fuel Reprocessing  

Energy Technology Data Exchange (ETDEWEB)

Reprocessing is essential to closing nuclear fuel cycle. Natural uranium contains only 0.7 percent 235U, the fissile (see glossary for technical terms) isotope that produces most of the fission energy in a nuclear power plant. Prior to being used in commercial nuclear fuel, uranium is typically enriched to 3–5% in 235U. If the enrichment process discards depleted uranium at 0.2 percent 235U, it takes more than seven tonnes of uranium feed to produce one tonne of 4%-enriched uranium. Nuclear fuel discharged at the end of its economic lifetime contains less one percent 235U, but still more than the natural ore. Less than one percent of the uranium that enters the fuel cycle is actually used in a single pass through the reactor. The other naturally occurring isotope, 238U, directly contributes in a minor way to power generation. However, its main role is to transmute into plutoniumby neutron capture and subsequent radioactive decay of unstable uraniumand neptuniumisotopes. 239Pu and 241Pu are fissile isotopes that produce more than 40% of the fission energy in commercially deployed reactors. It is recovery of the plutonium (and to a lesser extent the uranium) for use in recycled nuclear fuel that has been the primary focus of commercial reprocessing. Uraniumtargets irradiated in special purpose reactors are also reprocessed to obtain the fission product 99Mo, the parent isotope of technetium, which is widely used inmedical procedures. Among the fission products, recovery of such expensive metals as platinum and rhodium is technically achievable, but not economically viable in current market and regulatory conditions. During the past 60 years, many different techniques for reprocessing used nuclear fuel have been proposed and tested in the laboratory. However, commercial reprocessing has been implemented along a single line of aqueous solvent extraction technology called plutonium uranium reduction extraction process (PUREX). Similarly, hundreds of types of reactor fuels have been irradiated for different purposes, but the vast majority of commercial fuel is uranium oxide clad in zirconium alloy tubing. As a result, commercial reprocessing plants have relatively narrow technical requirements for used nuclear that is accepted for processing.

Harold F. McFarlane; Terry Todd

2013-11-01

427

Spent fuel leach tests  

International Nuclear Information System (INIS)

This presentation is divided into two parts, pre-WISAP and WISAP. The pre-WISAP leach tests were started before WISAP sponsorship and do not give data directly applicable to the spent fuel release modeling studies being done in WISAP Task 2. However, the general leaching trends have suggested the general approach to some mechanistic studies. The WISAP portion of this presentation was started under WISAP sponsorship and is designed to fulfill the requirement of obtaining radionuclide release rates from spent fuel and understanding the radionuclide release process under simulated geologic storage conditions

428

Fabrication of Pu fuels  

International Nuclear Information System (INIS)

COMMOX, created to promote and commercialize mixed oxide fuels for light water reactors rests its action on the available capacities at the Dessel BELGONUCLEAIRE fabrication plant and at the CEA Fabrication Complex of Cadarache (CFCa). The specific constraints of plutonium-fuel fabrication are reviewed: radiotoxicity of Pu, safety-criticality, accountancy of fissile materials, Am241. Then, this paper presents the different stages of the fabrication process and the experience acquired with the difficulties met during campaigns. The MELOX fabrication plant (capacity of 100 to 120 t/year) should start its production in 1993-1994

429

Nuclear fuel element cladding  

International Nuclear Information System (INIS)

Composite cladding for a nuclear fuel element containing fuel pellets is formed with a zirconium metal barrier layer bonded to the inside surface of a zirconium alloy tube. The composite tube is sized by a cold working tube reduction process and is heat treated after final reduction to provide complete recrystallization of the zirconium metal barrier layer and a fine-grained microstructure. The zirconium alloy tube is stress-relieved but is not fully recrystallized. The crystallographic structure of the zirconium metal barrier layer may be improved by compressive deformation such as shot-peening. (author)

430