Logistics of the research reactor fuel cycle: AREVA solutions

International Nuclear Information System (INIS)

Ohayon, David; Halle, Laurent; Naigeon, Philippe; Falgoux, Jean-Louis; Franck Obadia, Franck; Auziere, Philippe

2005-01-01

The AREVA Group Companies offer comprehensive solutions for the entire fuel cycle of Research Reactors comply with IAEA standards. CERCA and Cogema Logistics have developed a full partnership in the front end cycle. In the field of uranium CERCA and Cogema Logistics have the long term experience of the shipment from Russia, USA to the CERCA plant.. Since 1960, CERCA has manufactured over 300,000 fuel plates and 15,000 fuel elements of more than 70 designs. These fuel elements have been delivered to 40 research reactors in 20 countries. For the Back-End stage, Cogema and Cogema Logistics propose customised solutions and services for international shipments. Cogema Logistics has developed a new generation of packaging to meet the various needs and requirements of the Laboratories and Research Reactors all over the world, and complex regulatory framework. Comprehensive assistance dedicated, services, technical studies, packaging and transport systems are provided by AREVA for every step of research reactor fuel cycle. (author)

Entwicklung und Anwendung neuer NMR-Methoden: Orientierungsmedien zur Strukturbestimmung mit anisotropen Parametern und Metabonomics

OpenAIRE

Büchler, Silke

2014-01-01

Das Ziel dieser Arbeit war die Entwicklung und Anwendung neuer Orientierungsmedien zur Strukturbestimmung mit anisotropen Parametern, sowie die Etablierung von Metabonomics-Studien an Flüssigzellkulturen und Reispflanzen.

Supply Chain-based Solution to Prevent Fuel Tax Evasion

Energy Technology Data Exchange (ETDEWEB)

Franzese, Oscar [ORNL; Capps, Gary J [ORNL; Daugherty, Michael [United States Department of Transportation (USDOT), Federal Highway Administration (FHWA); Siekmann, Adam [ORNL; Lascurain, Mary Beth [ORNL; Barker, Alan M [ORNL

2016-01-01

The primary source of funding for the United States transportation system is derived from motor fuel and other highway use taxes. Loss of revenue attributed to fuel-tax evasion has been assessed to be somewhere between $1 billion per year, or approximately 25% of the total tax collected. Any solution that addresses this problem needs to include not only the tax-collection agencies and auditors, but also the carriers transporting oil products and the carriers customers. This paper presents a system developed by the Oak Ridge National Laboratory for the Federal Highway Administration which has the potential to reduce or eliminate many fuel-tax evasion schemes. The solution balances the needs of tax-auditors and those of the fuel-hauling companies and their customers. The technology was deployed and successfully tested during an eight-month period on a real-world fuel-hauling fleet. Day-to-day operations of the fleet were minimally affected by their interaction with this system. The results of that test are discussed in this paper.

Sustainable Solutions for Nuclear used Fuels Interim Storage

International Nuclear Information System (INIS)

Arslan, Marc; Favet, Dominique; Issard, Herve; Le Jemtel, Amaury; Drevon, Caroline

2014-01-01

AREVA has a unique experience in providing sustainable solutions for used fuel management, fitted with the needs of different customers in the world and with regulation in different countries. These solutions entail both recycling and interim storage technologies. In a first part, we will describe the various types of solutions for Interim Storage of UNF that have been implemented around the world for interim storage at reactor or centralized Pad solution in canisters dry storage, vault type storages for dry storage, dry storage of transportation casks (dual purpose) pools for wet storage, The experience for all these different families of interim storages in which AREVA is involved is extensive and will be discussed with respect to the new challenges: increase of the duration of the interim storage (long term interim storage) increase of burn up of the fuels In a second part of the presentation, special recycling features will be presented. In that case, interim storage of the used fuels is ensured in pools. This provides in the long term good conditions for the behaviour of the fuel and its retrievability. With recycling, the final waste (Universal Canister of vitrified fission products and compacted hulls and end pieces): is stable and licensed in many countries for the final disposal (France, UK, Belgium, NL, Switzerland, Germany, Japan, upcoming: Spain, Australia, Italy). Presents neither safety criticality risks nor proliferation risks (AREVA conditioned HLW and LL-ILW are free of IAEA safeguard constraints thanks to AREVA process high recovery and purification yields). It can therefore be safely stored in interim storage for more than 100 years before final disposal. Some economic considerations will also be discussed. In particular, in the case of long term interim storage of used fuels, there are growing uncertainties regarding the future needs of repackaging and transportation, which can result in future cost overruns. Meanwhile, in the recycling policy

Fuel handling solutions to power pulse at Bruce NGS A

International Nuclear Information System (INIS)

Day, R.C.

1996-01-01

In response to the discovery of the power pulse problem in March of 1993, Bruce A has installed flow straightening shield plugs in the inner zone channels of all units to partially reduce the gap and gain an increase in reactor power to 75%. After review and evaluation of solutions to manage the gap, including creep compensators and long fuel bundles, efforts have focused on a different solution involving reordering the fuel bundles to reverse the burnup profile. This configuration is maintained by fuelling with the flow and providing better support to the highly irradiated downstream fuel bundles by changing the design of the outlet shield plug. Engineering changes to the fuel handling control system and outlet shield plug are planned to be implemented starting in June 1996, thereby eliminating the power pulse problem and restrictions on reactor operating power. (author). 2 refs., 1 tab., 2 figs

Fuel handling solutions to power pulse at Bruce NGS A

Energy Technology Data Exchange (ETDEWEB)

Day, R C [Ontario Hydro, Tiverton, ON (Canada). Bruce Nuclear Generating Station-A

1997-12-31

In response to the discovery of the power pulse problem in March of 1993, Bruce A has installed flow straightening shield plugs in the inner zone channels of all units to partially reduce the gap and gain an increase in reactor power to 75%. After review and evaluation of solutions to manage the gap, including creep compensators and long fuel bundles, efforts have focused on a different solution involving reordering the fuel bundles to reverse the burnup profile. This configuration is maintained by fuelling with the flow and providing better support to the highly irradiated downstream fuel bundles by changing the design of the outlet shield plug. Engineering changes to the fuel handling control system and outlet shield plug are planned to be implemented starting in June 1996, thereby eliminating the power pulse problem and restrictions on reactor operating power. (author). 2 refs., 1 tab., 2 figs.

Massachusetts Fuel Cell Bus Project: Demonstrating a Total Transit Solution for Fuel Cell Electric Buses in Boston

Energy Technology Data Exchange (ETDEWEB)

2017-05-22

The Federal Transit Administration's National Fuel Cell Bus Program focuses on developing commercially viable fuel cell bus technologies. Nuvera is leading the Massachusetts Fuel Cell Bus project to demonstrate a complete transit solution for fuel cell electric buses that includes one bus and an on-site hydrogen generation station for the Massachusetts Bay Transportation Authority (MBTA). A team consisting of ElDorado National, BAE Systems, and Ballard Power Systems built the fuel cell electric bus, and Nuvera is providing its PowerTap on-site hydrogen generator to provide fuel for the bus.

Entwicklung eines kontinuierlichen Verfahrens zur enzymkatalysierten Synthese eines strukturierten Triglycerides

OpenAIRE

Stadler, Hans-Gerhard

2005-01-01

Ausgangspunkt für die in der vorliegenden Arbeit durchgeführten Entwicklung eines kontinuierlichen Verfahrens zur Synthese des strukturierten Triglycerides 1,3-Oleyl-2-palmitoylglycerin war die von Schmid [Schmid 1999] entwickelte lipase-katalysierte Zwei-Schritt-Synthese für strukturierte Triglyceride vom Typ ABA [European Patent Application; EP 0 882 797 A2]. In der ersten Reaktionsstufe dieser zweistufigen Umesterung wird in einer Folgereaktion das Substrat Tripalmitin mit Hilfe ein...

Solution of the conjugated heat transfer problem for the fuel elements assemblies

International Nuclear Information System (INIS)

Golba, V.S.; Ivanenko, I.J.; Zinina, G.A.

1997-01-01

The paper presents the assemblies conjugated heat conductivity problem calculation and experimental method. The method is based on the temperature superposition modified concept and subchannel method and allows to predict the fuel elements surface temperatures with availability of fuel elements inside structure of any complication caused by technological and working defects and with availability of depositions with low heat conductivity on the fuel elements surfaces. According to the method developed the partial solutions of the heat conductivity equation at the heat removal boundaries (solid-liquid) are found separately for the fuel elements and for the liquid. The heat conductivity equation partial solutions for the fuel elements are predicted by calculations. The coolant heat conductivity equation partial solution ('influence functions') data massif is obtained in present work experimentally in the fuel assembly model consists of 7 tube bundle of fuel elements imitators placed in right grating with relative grating step equal to 1.1 and cooled by eutectic alloy Pb-Bi. It is shown that 'subchannel prediction method' decreases the crosswise heat transfer in comparison with crosswise heat transfer, when the fuel element inside structure is taken into account. Also in the paper it is shown that it is possible to realize the assembly temperature prediction method suggested without carrying out the experiments in the assembly's model in order to get the external problem influence functions'. (author)

Evaluation of Purging Solutions for Military Fuel Tanks

National Research Council Canada - National Science Library

Rhee, In-Sik

2003-01-01

.... It is also a biodegradable water based solvent. Because of this property, US Army has used this environmentally friendly solvent as a purging solution in all military fuel tanks including Heavy Expanded Mobility Truck (HEMTT...

Asymptotic Solutions of Serial Radial Fuel Shuffling

Directory of Open Access Journals (Sweden)

Xue-Nong Chen

2015-12-01

Full Text Available In this paper, the mechanism of traveling wave reactors (TWRs is investigated from the mathematical physics point of view, in which a stationary fission wave is formed by radial fuel drifting. A two dimensional cylindrically symmetric core is considered and the fuel is assumed to drift radially according to a continuous fuel shuffling scheme. A one-group diffusion equation with burn-up dependent macroscopic coefficients is set up. The burn-up dependent macroscopic coefficients were assumed to be known as functions of neutron fluence. By introducing the effective multiplication factor keff, a nonlinear eigenvalue problem is formulated. The 1-D stationary cylindrical coordinate problem can be solved successively by analytical and numerical integrations for associated eigenvalues keff. Two representative 1-D examples are shown for inward and outward fuel drifting motions, respectively. The inward fuel drifting has a higher keff than the outward one. The 2-D eigenvalue problem has to be solved by a more complicated method, namely a pseudo time stepping iteration scheme. Its 2-D asymptotic solutions are obtained together with certain eigenvalues keff for several fuel inward drifting speeds. Distributions of the neutron flux, the neutron fluence, the infinity multiplication factor kinf and the normalized power are presented for two different drifting speeds.

Entwicklung und Evaluation computerbasierter Trainingsaufgaben für das wissenschaftliche Schreiben

OpenAIRE

Proske, Antje

2006-01-01

Wissenschaftliches Schreiben ist eine sehr komplexe Aufgabe, die eine Vielzahl unterschiedlicher Aktivitäten umfasst. Viele Studierende haben jedoch Schwierigkeiten, die damit verbundenen Anforderungen selbständig zu bewältigen. Im Mittelpunkt des Interesses der vorliegenden Arbeit stand daher die Entwicklung und Evaluation interaktiver computerbasierter Trainingsaufgaben, die Studienanfänger beim Erwerb von Grundkompetenzen des wissenschaftlichen Schreibens unterstützen. Zentrale Anliegen di...

3D-Master-Leitungssatz - Konzept zur Entwicklung von Leitungssätzen als 3D-Master in einem realistischen, vollständigen DMU-Modell

OpenAIRE

Neckenich, Jonas

2017-01-01

Die Fokussierung auf eine 3D-orientierte Produktentwicklung und einen durchgängigen 3D-Prozess wird in der heutigen Industrie immer wichtiger. Im Entwicklungsprozess des Kabelbaums trifft dabei die bauraumorientierte 3D-Entwicklung auf die produktorientierte 2D-Entwicklung. Die unsaubere Trennung zwischen bestehenden Definitionssystemen im heutigen Entwicklungsprozess führt dabei zu Datendiskrepanzen, Zeitverzug und Fehlern. Im Digital Mock-Up, welcher zur digitalen Absicherung des Fahrzeugs ...

Entwicklung von Cysteinproteaseinhibitoren - ein klassischer und ein kombinatorischer Ansatz zur Inhibitoroptimierung

OpenAIRE

Machon, Uwe Rainer

2009-01-01

Ziel der Dissertation „Entwicklung von Cysteinproteaseinhibitoren – ein klassischer und ein kombinatorischer Ansatz zur Inhibitoroptimierung“ war die Optimierung von neuen Inhibitoren von Falcipain-2 und Rhodesain als neue potentielle Wirkstoffe gegen Malaria bzw. die Schlafkrankheit über zwei verschiedene Methoden. Es handelt sich hierbei um einen klassischen und einen kombinatorischen Ansatz. Der klassische Ansatz basiert auf einer Struktur, deren Aktivität per Zufall entdeckt wurde. In Scr...

Dissolution of powdered spent fuel and U crystallization from actual dissolver solution for 'NEXT' process development

International Nuclear Information System (INIS)

Nomura, Kazunori; Hinai, Hiroshi; Nakahara, Masaumi; Kaji, Naoya; Kamiya, Masayoshi; Ohyama, Koichi; Sano, Yuichi; Washiya, Tadahiro; Komaki, Jun

2008-01-01

The beaker-scale experiments on the effective powdered fuel dissolution and the U crystallization from dissolver solution with the irradiated MOX fuel from the experimental fast reactor 'JOYO' were carried out. The powdered fuel was effectively dissolved into the nitric acid solution. In the U crystallization experiments, U crystal was obtained from the actual dissolver solution without any addition of reagent. (authors)

Solution High-Energy Burst Assembly (SHEBA) results from subprompt critical experiments with uranyl fluoride fuel

International Nuclear Information System (INIS)

Cappiello, C.C.; Butterfield, K.B.; Sanchez, R.G.

1997-10-01

The Solution High-Energy Burst Assembly (SHEBA) was originally constructed during 1980 and was designed to be a clean free-field geometry, right-circular, cylindrically symmetric critical assembly employing U(5%)O 2 F 2 solution as fuel. A second version of SHEBA, employing the same fuel but equipped with a fuel pump and shielding pit, was commissioned in 1993. This report includes data and operating experience for the 1993 SHEBA only. Solution-fueled benchmark work focused on the development of experimental measurements of the characterization of SHEBA; a summary of the results are given. A description of the system and the experimental results are given in some detail in the report. Experiments were designed to: (1) study the behavior of nuclear excursions in a low-enrichment solution, (2) evaluate accidental criticality alarm detectors for fuel-processing facilities, (3) provide radiation spectra and dose measurements to benchmark radiation transport calculations on a low-enrichment solution system similar to centrifuge enrichment plants, and (4) provide radiation fields to calibrate personnel dosimetry. 15 refs., 37 figs., 10 tabs

A review of irradiation induced re-solution in oxide fuels

International Nuclear Information System (INIS)

Turnbull, J.A.

1980-01-01

The paper reviews the existing experimental evidence for irradiation induced re-solution and also possible explanations for the mechanism. The importance of re-solution is considered with regard to intragranular bubbles and the accumulation of gas on grain boundaries. It is concluded that re-solution is most effective at low temperatures and could account for the present concern over gas release in high burn-up water reactor fuel assemblies. (author)

Prospektive Entwicklung des postoperativen Sprachverstehens nach Tympanoplastik bei chronischer Otitis media

OpenAIRE

Knof, B; Plotz, K; Krack, A; Stumper, J; Schönfeld, R

2013-01-01

Einleitung: Tympanoplastiken I/III bei chron. Otitis media COM (mesotympanalis CMOM und epitympanalis CEOM). In der Literatur werden erfolgreiche operative Behandlungen mit Verringerung der Schallleitungskomponente (air-bone gap) belegt (Gierke et al. 2011). Aus Sicht des Patienten steht die Verbesserung des Hörvermögens und des Sprachverstehens im Alltag im Vordergrund. Das Ziel war die Untersuchung der Entwicklung des Hörvermögens in Ruhe sowie im Störgeräusch.Methoden: An den Hör- und Sp...

Overview of the EBFGT installation solutions applicable for flue gases from various fuels combustion

International Nuclear Information System (INIS)

Chmielewski, A.G.; Tyminski, B.; Pawelec, A.; Zimek, Z.; Licki, J.

2011-01-01

The overview of the solutions used in EBFGT process and adaptation of process parameters for flue gas from combustion of various fuels was presented. The inlets parameters of flue gas from four fuels with high emission of pollutants, process parameters and process constrain were analysed. Also the main problems of this technology and their solutions were presented. (author)

Overview of the EBFGT installation solutions applicable for flue gases from various fuels combustion

Energy Technology Data Exchange (ETDEWEB)

Chmielewski, A. G.; Tyminski, B.; Pawelec, A.; Zimek, Z. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland); Licki, J. [Institute of Atomic Energy, Otwock-Świerk (Poland)

2011-07-01

The overview of the solutions used in EBFGT process and adaptation of process parameters for flue gas from combustion of various fuels was presented. The inlets parameters of flue gas from four fuels with high emission of pollutants, process parameters and process constrain were analysed. Also the main problems of this technology and their solutions were presented. (author)

Bio-inspired solutions in design for manufacturing of micro fuel cell

DEFF Research Database (Denmark)

Omidvarnia, Farzaneh; Hansen, Hans Nørgaard

2014-01-01

In this paper the application of biomimetic principles in design for micro manufacturing is investigated. A micro direct methanol fuel cell (μDMFC) for power generation in hearing aid devices is considered as the case study in which the bioinspired functions are replicated. The focus in design of μ......DMFC is mainly on solving the problem of fuel delivery to the anode in the fuel chamber. Two different biological phenomena are suggested, and based on them different bioinspired solutions are proposed and modeled in CAD software. Considering the manufacturing constraints and design specifications...

Solar fuels via artificial photosynthesis: From homogeneous photocatalysis in solution to a photoelectrochemical cell

NARCIS (Netherlands)

Chen, H.-C.

2016-01-01

The conversion and storage of solar energy into fuels provides a valuable solution for the future energy demand of our society. Making fuels via artificial photosynthesis, the so-called solar-to-fuel approach, is viewed as one of the most promising ways to produce clean and renewable energy.

Wie Geschwister sich in ihrer musikalischen Entwicklung beeinflussen. Ergebnisse einer Erhebung mit offenem Fragebogen

OpenAIRE

Olbertz, Franziska

2012-01-01

Die Rolle der Geschwister in der musikalischen Entwicklung sollte anhand empirischer Daten fassbar gemacht und damit eine Forschungslücke der musikalischen Entwicklungspsychologie geschlossen werden. Dazu wurden in der aktuellen Studie zunächst die Formen der musikalischen Beeinflussung unter Geschwistern qualitativ erhoben und kategorisiert. Einfache quantitative Analysen desselben Materials sollten auch Hypothesen über die Bedeutung einiger Variablen ermöglichen, wie z. B. des Altersabstand...

Selecting enhancing solutions for electrokinetic remediation of dredged sediments polluted with fuel.

Science.gov (United States)

Rozas, F; Castellote, M

2015-03-15

In this paper a procedure for selecting the enhancing solutions in electrokinetic remediation experiments is proposed. For this purpose, dredged marine sediment was contaminated with fuel, and a total of 22 different experimental conditions were tested, analysing the influence of different enhancing solutions by using three commercial non-ionic surfactants, one bio-surfactant, one chelating agent, and one weak acid. Characterisation, microelectrophoretic and electrokinetic remediation trials were carried out. The results are explained on the basis of the interactions between the fuel, the enhancing electrolytes and the matrix. For one specific system, the electrophoretic zeta potential, (ζ), of the contaminated matrix in the solution was found to be related to the electroosmotic averaged ζ in the experiment and not to the efficiency in the extraction. This later was correlated to a parameter accounting for both contributions, the contaminant and the enhancing solution, calculated on the basis of differences in the electrophoretic ζ in different conditions which has allowed to propose a methodology for selection of enhancing solutions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Supply Chain-Based Solution to Prevent Fuel Tax Evasion: Final Report

Energy Technology Data Exchange (ETDEWEB)

Capps, Gary J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Engineering and Transportation Sciences Division; Franzese, Oscar [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Engineering and Transportation Sciences Division; Lascurain, Mary Beth [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Engineering and Transportation Sciences Division; Siekmann, Adam [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Engineering and Transportation Sciences Division; Barker, Alan M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Electrical and Electronics Systems Research Division

2016-07-28

The primary source of funding for the United States transportation system is derived from motor fuel and other highway use taxes. Loss of revenue attributed to fuel-tax evasion has been assessed to be somewhere between 1 billion and 3 billion per year. Any solution that addresses this problem needs to include not only the tax-collection agencies and auditors, but also the carriers transporting oil products and the carriers customers. This report presents a system developed by the Oak Ridge National Laboratory (ORNL) for the Federal Highway Administration which has the potential to reduce or eliminate many fuel-tax evasion schemes. The solution balances the needs of tax-auditors and those of the fuel-hauling companies and their customers. The system has three main components. The on-board subsystem combined sensors, tracking and communication devices, and software (the on-board Evidential Reasoning System, or obERS) to detect, monitor, and geo-locate the transfer of fuel among different locations. The back office sub-system (boERS) used self-learning algorithms to determine the legitimacy of the fuel loading and offloading (important for tax auditors) and detect potential illicit operations such as fuel theft (important for carriers and their customers, and may justify the deployment costs). The third sub-system, the Fuel Distribution and Auditing System or FDAS, is a centralized database, which together with a user interface allows tax auditors to query the data submitted by the fuel-hauling companies and correlate different parameters to quickly identify any anomalies. Industry partners included Barger Transport of Weber City, Virginia (fleet); Air-Weigh, of Eugene, Oregon (and their wires and harnesses); Liquid Bulk Tank (LBT) of Omaha, Nebraska (three five-compartment trailers); and Innovative Software Engineering (ISE) of Coralville, Iowa(on-board telematics device and back-office system). ORNL conducted a pilot test with the three instrumented vehicles

Solution High-Energy Burst Assembly (SHEBA) results from subprompt critical experiments with uranyl fluoride fuel

International Nuclear Information System (INIS)

Cappiello, C.C.; Butterfield, K.B.; Sanchez, R.G.; Bounds, J.A.; Kimpland, R.H.; Damjanovich, R.P.; Jaegers, P.J.

1997-01-01

Experiments were performed to measure a variety of parameters for SHEBA: behavior of the facility during transient and steady-state operation; characteristics of the SHEBA fuel; delayed-critical solution height vs solution temperature; initial reactor period and reactivity vs solution height; calibration of power level vs reactor power instrumentation readings; flux profile in SHEBA; radiation levels and neutron spectra outside the assembly for code verification and criticality alarm and dosimetry purposes; and effect on reactivity of voids in the fuel

Used Fuel Logistics: Decades of Experience with transportation and Interim storage solutions

Energy Technology Data Exchange (ETDEWEB)

Orban, G.; Shelton, C.

2015-07-01

Used fuel inventories are growing worldwide. While some countries have opted for a closed cycle with recycling, numerous countries must expand their interim storage solutions as implementation of permanent repositories is taking more time than foreseen. In both cases transportation capabilities will have to be developed. AREVA TN has an unparalleled expertise with transportation of used fuel. For more than 50 years AREVA TN has safely shipped more than 7,000 used fuel transport casks. The transportation model that was initially developed in the 1970s has been adapted and enhanced over the years to meet more restrictive regulatory requirements and evolving customer needs, and to address public concerns. The numerous “lessons learned” have offered data and guidance that have allowed for also efficient and consistent improvement over the decades. AREVA TN has also an extensive experience with interim dry storage solutions in many countries on-site but also is working with partners to developed consolidated interim storage facility. Both expertise with storage and transportation contribute to safe, secure and smooth continuity of the operations. This paper will describe decades of experience with a very successful transportation program as well as interim storage solutions. (Author)

Strategies and solutions in the temporary management of spent fuel in Spain

International Nuclear Information System (INIS)

Martinez Abad, J. E.; Rivera, M. I.

2009-01-01

The basic strategy for the spent fuel and HLW management contemplated in the Sixth General Radioactive Waste Plan focused on the centralised interim storage of spent fuel, based on proved dry storage system technologies, over the time periods required until their definitive or very long term management. Specially, the solution proposed as the most suitable for the Spanish case is the construction of a centralised interim spent fuel and HLW storage facility (ATC) for which as site is being searched. Until it becomes in operation, the interim spent fuel storage will be safety performed in the NPP reracked spent fuel pools or individual ISFSI constructed in the NPP site, in those cases additional storage capacity is required. (Author) 22 refs

Method for recovering palladium and technetium values from nuclear fuel reprocessing waste solutions

Science.gov (United States)

Horwitz, E. Philip; Delphin, Walter H.

1979-07-24

A method for recovering palladium and technetium values from nuclear fuel reprocessing waste solutions containing these and other values by contacting the waste solution with an extractant of tricaprylmethylammonium nitrate in an inert hydrocarbon diluent which extracts the palladium and technetium values from the waste solution. The palladium and technetium values are recovered from the extractant and from any other coextracted values with a strong nitric acid strip solution.

Leading fuel cell projects ``PEM``; Brennstoffzellen-Leitprojekte ``PEM``

Energy Technology Data Exchange (ETDEWEB)

Isenberg, G

1996-12-31

Polymer electrolyte diaphragm fuel cells (PEMFC) are distinguished by high specific power densities which are necessary in the field of electrical drives, high efficiencies and no or very low emission of harmful substances, depending on the fuel. In the context of a leading project supported by BMBF, the development of improved and above all, more reasonably priced components for the PEMFC and the reforming of methanol is to work out the important technical basis for the subsequent economic conversion into a vehicle drive. (orig.) [Deutsch] Polymer-Elektrolyt-Membran-Brennstoffzellen (PEMFC) zeichnen sich durch hohe spezifische Leistungsdichten, wie sie im Bereich elektrischer Antriebe notwendig sind, hohe Wirkungsgrade und treibstoffabhaengig keine bzw. sehr niedrige Schadstoffemission aus. Im Rahmen eines BMBF-gefoerderten Leitprojekts sollen mit der Entwicklung verbesserter, vor allem kostenguenstiger Komponenten fuer die PEMFC und die Methanol-Reformierung wesentliche technologische Grundlagen fuer die anschliessende wirtschaftliche Umsetzung als Fahrzeugantrieb erarbeitet werden. (orig.)

Benchmark solution of contemporary PWR integral fuel burnable absorbers

International Nuclear Information System (INIS)

Stucker, D.L.; Hone, M.J.; Holland, R.A.

1993-01-01

This paper presents a closely controlled benchmark solution of the two major contemporary pressurized water reactor integral burnable absorber designs: zirconium diboride (ZrB 2 ) and gadolinia (Gd 2 O 3 ). The comparison is accomplished using self-generating equilibrium cycles with equal energy, equal discharge burnup, and equal safety constraints. The reference plant for this evaluation is a 3411-MW(thermal) Westinghouse four-loop nuclear steam supply system operating with an inlet temperature of 285.9 degrees C, a core coolant mass now rate of 16877.3 kg/s, and coolant pressure of 15.5 MPa. The reactor consists of 193 VANTAGE 5H fuel assemblies that are discharged at a region average burnup of 48.4 GWd/tonne U. Each fuel assembly contains a natural uranium axial blanket 15.24 cm long at the top and the bottom of the fuel rod. The burnable absorber rods are symmetrically radially dispersed within the fuel assembly such that intrabundle power peaking is minimized. The burnable absorber material for both ZrB 2 and Gd 2 O 3 is axially zoned to the central 304.8 cm of the absorber-bearing fuel rods. The fuel management was constrained such that the thermal and safety limitations of F δH q -5 /degrees C were simultaneously achieved. The maximum long-term operating soluble boron concentration was also limited to 446 effective full-power days (EFPDs) including 14 EFPDs of power coastdown were assumed

An alternative solution for heavy liquid metal cooled reactors fuel assemblies

Energy Technology Data Exchange (ETDEWEB)

Vitale Di Maio, Damiano, E-mail: damiano.vitaledimaio@uniroma1.it [“SAPIENZA” University of Rome – DIAEE, Corso Vittorio Emanuele II, 244, 00186 Rome (Italy); Cretara, Luca; Giannetti, Fabio [“SAPIENZA” University of Rome – DIAEE, Corso Vittorio Emanuele II, 244, 00186 Rome (Italy); Peluso, Vincenzo [“ENEA”, Via Martiri di Monte Sole 4, 40129 Bologna (Italy); Gandini, Augusto [“SAPIENZA” University of Rome – DIAEE, Corso Vittorio Emanuele II, 244, 00186 Rome (Italy); Manni, Fabio [“SRS Engineering Design S.r.l.”, Vicolo delle Palle 25-25/b, 00186 Rome (Italy); Caruso, Gianfranco [“SAPIENZA” University of Rome – DIAEE, Corso Vittorio Emanuele II, 244, 00186 Rome (Italy)

2014-10-15

Highlights: • A new fuel assembly locking system for heavy metal cooled reactor is proposed. • Neutronic, mechanical and thermal-hydraulic evaluations of the system behavior have been performed. • A comparison with other solutions has been presented. - Abstract: In the coming future, the electric energy production from nuclear power plants will be provided by both thermal reactors and fast reactors. In order to have a sustainable energy production through fission reactors, fast reactors should provide an increasing contribution to the total electricity production from nuclear power plants. Fast reactors have to achieve economic and technical targets of Generation IV. Among these reactors, Sodium cooled Fast Reactors (SFRs) and Lead cooled Fast Reactors (LFRs) have the greatest possibility to be developed as industrial power plants within few decades. Both SFRs and LFRs require a great R and D effort to overcome some open issues which affect the present designs (e.g. sodium-water reaction for the SFRs, erosion/corrosion for LFRs, etc.). The present paper is mainly focused on LFR fuel assembly (FA) design: issues linked with the high coolant density of lead or lead–bismuth eutectic cooled reactors have been investigated and an innovative solution for the core mechanical design is here proposed and analyzed. The solution, which foresees cylindrical fuel assemblies and exploits the buoyancy force due to the lead high density, allows to simplify the FAs locking system, to reduce their length and could lead to a more uniform neutron flux distribution.

Die Etablierung massenspektrometrischer quantitativer Studien des Herzproteoms während der embryonalen Entwicklung und der Alterung

OpenAIRE

Konzer, Anne

2012-01-01

Neue Erkenntnisse über die physiologischen, molekularen und pathologischen Prozesse im Herzen konnten im letzten Jahrzehnt anhand von Modellorganismen gewonnen werden. Die Entwicklung neuer Techniken ermöglichte außerdem die Etablierung umfangreicher und eindrucksvoller Studien basierend auf den neusten Mikroskopieverfahren, auf globalen Genexpressionsanalysen (Microarray) sowie auf modernen Massenspektrometrie (MS)- basierenden Proteinanalysen anhand von hochauflösenden Tandem-Massenspektrom...

A complete NUHOMS {sup registered} solution for storage and transport of high burnup spent fuel

Energy Technology Data Exchange (ETDEWEB)

Bondre, J. [Transnuclear, Inc. (AREVA Group), Fremont, CA (United States)

2004-07-01

The discharge burnups of spent fuel from nuclear power plants keep increasing with plants discharging or planning to discharge fuel with burnups in excess of 60,000 MWD/MTU. Due to limited capacity of spent fuel pools, transfer of older cooler spent fuel from fuel pool to dry storage, and very limited options for transport of spent fuel, there is a critical need for dry storage of high burnup, higher heat load spent fuel so that plants could maintain their full core offload reserve capability. A typical NUHOMS {sup registered} solution for dry spent fuel storage is shown in the Figure 1. Transnuclear, Inc. offers two advanced NUHOMS {sup registered} solutions for the storage and transportation of high burnup fuel. One includes the NUHOMS {sup registered} 24PTH system for plants with 90.7 Metric Ton (MT) crane capacity; the other offers the higher capacity NUHOMS {sup registered} 32PTH system for higher crane capacity. These systems include NUHOMS {sup registered} - 24PTH and -32PTH Transportable Canisters stored in a concrete storage overpack (HSM-H). These canisters are designed to meet all the requirements of both storage and transport regulations. They are designed to be transported off-site either directly from the spent fuel pool or from the storage overpack in a suitable transport cask.

Separation of lanthanum from nuclear fuel solutions by high performance liquid chromatography

International Nuclear Information System (INIS)

Lazar, G. C.; Petre, M.; Androne, G.; Benga, A.

2016-01-01

This paper presents the separation of uranium, praseodymium and lanthanum from nuclear fuel solutions by high performance liquid chromatography (HPLC). The aim of this study is to establish a minimum concentration of lanthanum which can be analyzed by high performance liquid chromatography, and also to study the effect of uranium concentration on the separation of praseodymium and lanthanum. Optimum gradient mode was established for mixture standard stoc solutions with uranium in a concentration of 1 mg/ml, praseodymium and lanthanum in a concentration range of 1-5 μg/ml from each element. These conditions were applied for the separation of lanthanum from a nuclear fuel solution in which praseodymium and lanthanum were added in a concentration of 3 μg/ml from each element. The elution behavior of lanthanum as a function of the pH and the concentration of the mobile phase, using a mixture of 1-octanesulfonic acid sodium salt with a-hidroxyisobutiric acid is presented. (authors)

Closed-form solution of a two-dimensional fuel temperature model for TRIGA-type reactors

Energy Technology Data Exchange (ETDEWEB)

Rivard, J B [Sandia Laboratories (United States)

1974-07-01

If azimuthal power density variations are ignored, the steady-state temperature distribution within a TRIGA-type fuel element is given by the solution of the Poisson equation in two dimensions (r and z) . This paper presents a closed-form solution of this equation as a function of the axial and radial power density profiles, the conductivity of the U-ZrH, the inlet temperature, specific heat and flow rate of the coolant, and the overall heat transfer coefficient. The method begins with the development of a system of linear ordinary differential equations describing mass and energy balances in the fuel and coolant. From the solution of this system, an expression for the second derivative of the fuel temperature distribution in the axial (z) direction is found. Substitution of this expression into the Poisson equation for T(r,z) reduces it from a partial differential equation to an ordinary differential equation in r, which is subsequently solved in closed-form. The results of typical calculations using the model are presented. (author)

Numerical solution of the elastic non-axial contact between pellet and cladding of fuel rod in PWR

International Nuclear Information System (INIS)

Zymak, J.

1987-08-01

Elastic non-axial contacts between the pellet and the cladding of a fuel rod in a pressurized water reactor were calculated. The existence and the uniqueness of the solution were proved. The problem was approximated by the finite element method and quadratic programming was used for the solution. The results will be used in the solution of the probabilistic model of a fuel rod with non-axial pellets in a PWR. (author). 10 figs., 4 tabs., 10 refs

Energy report for Bavaria, 1996/97. Data on the development of the Bavarian energy industry, with an energy balance; Energiebericht Bayern 1996/97. Daten zur Entwicklung der bayerischen Energiewirtschaft mit Energiebilanz

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-04-01

The report presents the energy balance for Bavaria and provides information on: Bavarian energy industry; structure and development of primary and end-use energy consumption; situation and development of energy sources (electricity, gas, mineral oil, coal, district heating). (orig.) [Deutsch] Der Bericht enthaelt die Energiebilanz Bayern fuer das Berichtsjahr und bietet Informationen zur Energiewirtschaft in Bayern, zur Struktur und Entwicklung des Primaer- und Endenergieverbrauchs und zur Situation und Entwicklung bei den einzelnen Energietraegern (Elektrizitaet, Gas, Mineraloel, Kohle, Fernwaerme). (orig.)

Post-precipitations from MOX fuel solutions and analysis of microparticle formation in the PUREX process

International Nuclear Information System (INIS)

Henkelmann, R.; Baumgaertner, F.; Klein, F.; Niestroj, B.

1989-01-01

Subsequent precipitates of feed solutions from reprocessing were examined with the aid of the SEM-EDX method. On the one hand the examinations give information about the particle form and size distribution, on the other hand about the element distribution in single particles with consideration of the radiation data of the fuel. The subsequent precipitation samples which are examined in this study were taken after different residence times of the clarified fuel solutions. The examinations give information about the kind, element frequency, distribution and stoichiometry of single particles of the submicro- and microrange. (RB) [de

Stress Analysis of a TRISO Coated Particle Fuel by Using ABAQUS Finite Element Visco-Elastoplastic Solutions

International Nuclear Information System (INIS)

Cho, Moon Sung; Kim, Y. M.; Lee, Y. W.

2006-01-01

The fundamental design for a gas-cooled reactor relies on an understanding of the behavior of a coated particle fuel. KAERI, which has been carrying out the Korean VHTR (Very High Temperature modular gas cooled Reactor) Project since 2004, is developing a fuel performance analysis code for a VHTR named COPA (COated Particle fuel Analysis). A validation of COPA was attempted by comparing its benchmark results with the visco-elastic solutions obtained from the ABAQUS code calculations for the IAEA-CRP-6 TRISO coated particle benchmark problems involving a creep, swelling, and pressure. However, the ABAQUS finite element model used for the above-mentioned analysis did not consider the material nonlinearity of the SiC coating layer that showed stress levels higher than the assumed yield point of the material. In this study, a consideration of the material nonlinearity is included in the ABAQUS model to obtain the visco-elastoplastic solutions and the results are compared with the visco-elastic solutions obtained from the previous ABAQUS model

Calculational assessment of critical experiments with mixed-oxide fuel pin arrays moderated by organic solution

International Nuclear Information System (INIS)

Smolen, G.R.; Funabashi, H.

1987-01-01

Critical experiments have been conducted with organically moderated mixed-oxide (MOX) fuel pin assemblies at the Pacific Northwest Lab. Critical Mass Lab. These experiments are part of a joint exchange program between the US Dept. of Energy and the Power Reactor and Nuclear Fuel Development Corp. of Japan in the area of criticality data development. The purpose of these experiments is to benchmark computer codes and cross-section libraries and to assess the reactivity difference between systems moderated by water and those moderated by an organic solution. Past studies have indicated that some organic mixtures may be better moderators than water. This topic is of particular importance to the criticality safety of fuel processing plants where fissile material is dissolved in organic solutions during the solvent extraction process. In the past, it has been assumed that the codes and libraries benchmarked with water-moderated experiments were adequate when performing design and licensing studies of organically moderated systems. Calculations presented in this paper indicated that the Scale code system and the 27-energy-group cross-section library accurately compute k/sub eff/ for organically moderated MOX fuel pin assemblies. Furthermore, the reactivity of an organic solution with a 32 vol % TBP/68 vol% NPH mixture in a heterogeneous configuration is the same, for practical purposes, as water

Calculational assessment of critical experiments with mixed oxide fuel pin arrays moderated by organic solution

International Nuclear Information System (INIS)

Smolen, G.R.

1987-01-01

Critical experiments have been conducted with organic-moderated mixed oxide (MOX) fuel pin assemblies at the Pacific Northwest Laboratory (PNL) Critical Mass Laboratory (CML). These experiments are part of a joint exchange program between the United States Department of Energy (USDOE) and the Power Reactor and Nuclear Fuel Development Corporation (PNC) of Japan in the area of criticality data development. The purpose of these experiments is to benchmark computer codes and cross-section libraries and to assess the reactivity difference between systems moderated by water and those moderated by an organic solution. Past studies have indicated that some organic mixtures may be better moderators than water. This topic is of particular importance to the criticality safety of fuel processing plants where fissile material is dissolved in organic solutions during the solvent extraction process. In the past, it has been assumed that the codes and libraries benchmarked with water-moderated experiments were adequate when performing design and licensing studies of organic-moderated systems. Calculations presented in this paper indicated that the SCALE code system and the 27-energy-group cross-section accurately compute k-effectives for organic moderated MOX fuel-pin assemblies. Furthermore, the reactivity of an organic solution with a 32-vol-% TBP/68-vol-% NPH mixture in a heterogeneous configuration is the same, for practical purposes, as water. 5 refs

Safe and reliable fuel solutions

International Nuclear Information System (INIS)

2013-01-01

Published by AREVA, this booklet highlights the main aspects regarding fuel-related activities within this company. It outlines the efforts to improve all the involved processes, briefly describes the components and structure of fuel assemblies, gives an overview of Areva's different activities related to nuclear fuels (design, variety of products, fabrication, services). It outlines the relationship with the client for each of these activities, briefly describes the different parts of a fuel assembly for a PWR, outlines the importance given to quality for the fabrication processes, and indicates the different services provided by AREVA to its clients (handling, maintenance, controls, inspection, repair, training, etc.)

"Bildung für nachhaltige Entwicklung" - die Sicht der Kinder : Ergebnisse aus dem weltweiten OMEP-Projekt

OpenAIRE

Engdahl, Ingrid

2017-01-01

Während der UNESCO Dekade „Bildung für nachhaltige Entwicklung“ (BNE) führte die Weltorganisation für Frühe Bildung (OMEP) zwischen 2009-2014 ein umfangreiches Projekt zum Thema Nachhaltigkeit durch. Das übergeordnete Ziel des Projektes war das Bewußtsein der OMEP Mitglieder und der internationalen Fachgemeinde für die Bildung für nachhaltige Entwicklung (BNE) zu stärken. Dabei wurde ein besonderer Fokus auf die kindorientierte Perspektive gelegt.

Performance of direct alcohol fuel cells fed with mixed methanol/ethanol solutions

Energy Technology Data Exchange (ETDEWEB)

Wongyao, N. [The Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, 126 Pracha-Uthit Rd., Bang Mod, Thung Khru, Bangkok 10140 (Thailand); Therdthianwong, A., E-mail: apichai.the@kmutt.ac.t [Fuel Cell and Hydrogen Research and Engineering Center, Clean Energy System Group, PDTI, King Mongkut' s University of Technology Thonburi, 126 Pracha-Uthit Rd., Bang Mod, Thung Khru, Bangkok 10140 (Thailand); Therdthianwong, S. [Department of Chemical Engineering, Faculty of Engineering, King Mongkut' s University of Technology Thonburi, 126 Pracha-Uthit Rd., Bang Mod, Thung Khru, Bangkok 10140 (Thailand)

2011-07-15

Research highlights: {yields} We examined the performance of direct alcohol fuel cells fed with mixed alcohol. {yields} PtRu-PtSn/C and PtRu/C as catalysts for mixed alcohol electrooxidation reaction. {yields} Misplace adsorption of ethanol on PtRu/C caused the cell performance drop. {yields} PtRu/C showed higher performance than PtRu-PtSn/C for mixed alcohol fuel. -- Abstract: In combining the advantages of both methanol and ethanol, direct alcohol fuel cells fed with mixed alcohol solutions (1 M methanol and 1 M ethanol in varying volume ratios) were tested for performance. Employing a PtRu-PtSn/C catalyst as anode, cell performance was found to diminish rapidly even at 2.5% by volume ethanol mixture. Further increase of ethanol exceeded 10%, the cell performance gradually decreased and finally approached that of direct ethanol fuel cells. The causes of the decrease in the cell performance were the slow electro-oxidation of ethanol and the misplaced adsorption of ethanol on PtRu/C. By comparing the PtRu-PtSn/C cell with the PtRu/C cell operated with mixed alcohol solutions, the cell using PtRu/C as an anode catalyst provided higher power density since more PtRu/C surface was available for methanol oxidation reaction and less ohmic resistance of PtRu/C than that of PtRu-PtSn/C. In order to reach optimization of DAFC performance fed with mixed alcohol, the electrocatalyst used for the anode must selectively adsorb an alcohol, especially ethanol.

Performance of direct alcohol fuel cells fed with mixed methanol/ethanol solutions

International Nuclear Information System (INIS)

Wongyao, N.; Therdthianwong, A.; Therdthianwong, S.

2011-01-01

Research highlights: → We examined the performance of direct alcohol fuel cells fed with mixed alcohol. → PtRu-PtSn/C and PtRu/C as catalysts for mixed alcohol electrooxidation reaction. → Misplace adsorption of ethanol on PtRu/C caused the cell performance drop. → PtRu/C showed higher performance than PtRu-PtSn/C for mixed alcohol fuel. -- Abstract: In combining the advantages of both methanol and ethanol, direct alcohol fuel cells fed with mixed alcohol solutions (1 M methanol and 1 M ethanol in varying volume ratios) were tested for performance. Employing a PtRu-PtSn/C catalyst as anode, cell performance was found to diminish rapidly even at 2.5% by volume ethanol mixture. Further increase of ethanol exceeded 10%, the cell performance gradually decreased and finally approached that of direct ethanol fuel cells. The causes of the decrease in the cell performance were the slow electro-oxidation of ethanol and the misplaced adsorption of ethanol on PtRu/C. By comparing the PtRu-PtSn/C cell with the PtRu/C cell operated with mixed alcohol solutions, the cell using PtRu/C as an anode catalyst provided higher power density since more PtRu/C surface was available for methanol oxidation reaction and less ohmic resistance of PtRu/C than that of PtRu-PtSn/C. In order to reach optimization of DAFC performance fed with mixed alcohol, the electrocatalyst used for the anode must selectively adsorb an alcohol, especially ethanol.

Solution combustion synthesis of strontium aluminate, SrAl2O4, powders: single-fuel versus fuel-mixture approach.

Science.gov (United States)

Ianoş, Robert; Istratie, Roxana; Păcurariu, Cornelia; Lazău, Radu

2016-01-14

The solution combustion synthesis of strontium aluminate, SrAl2O4, via the classic single-fuel approach and the modern fuel-mixture approach was investigated in relation to the synthesis conditions, powder properties and thermodynamic aspects. The single-fuel approach (urea or glycine) did not yield SrAl2O4 directly from the combustion reaction. The absence of SrAl2O4 was explained by the low amount of energy released during the combustion process, in spite of the highly negative values of the standard enthalpy of reaction and standard Gibbs free energy. In the case of single-fuel recipes, the maximum combustion temperatures measured by thermal imaging (482 °C - urea, 941 °C - glycine) were much lower than the calculated adiabatic temperatures (1864 °C - urea, 2147 °C - glycine). The fuel-mixture approach (urea and glycine) clearly represented a better option, since (α,β)-SrAl2O4 resulted directly from the combustion reaction. The maximum combustion temperature measured in the case of a urea and glycine fuel mixture was the highest one (1559 °C), which was relatively close to the calculated adiabatic temperature (1930 °C). The addition of a small amount of flux, such as H3BO3, enabled the formation of pure α-SrAl2O4 directly from the combustion reaction.

Renewables in figures. National and international trends in 2016; Erneuerbare Energien in Zahlen. Nationale und internationale Entwicklung im Jahr 2016

Energy Technology Data Exchange (ETDEWEB)

NONE

2017-09-15

The expansion of renewable energies is a central pillar of the energy transition. The development is positive: In 2016, renewable energies accounted for 31.7 percent of total gross electricity consumption. The brochure informs about the progress achieved in the further development of renewable energies in Germany, Europe and the world. The data on the development of renewable energies in Germany is based on the results of the Working Group on Renewable Energy Statistics (AGEE-Stat), which compiles the balance sheet of renewable energies for Germany on behalf of the BMWi. The data published here are a snapshot with the editorial deadline of August 2016 - they are still provisional in some places, especially for 2016. At the same time, current time series on the development of renewable energies in Germany since 1990 as well as a variety of graphs are published on the websites of the BMWi. These time series and graphs will be updated at the turn of the year 2017/2018. [German] Der Ausbau der erneuerbaren Energien ist eine zentrale Saeule der Energiewende. Die Entwicklung ist positiv: Im Jahr 2016 hatten die erneuerbare Energien einen Anteil von 31,7 Prozent am gesamten Bruttostromverbrauch. Mit der Broschuere wird ueber den erreichten Fortschritt beim weiteren Ausbau der Erneuerbaren Energien in Deutschland, in Europa und der Welt informiert. Grundlage der Daten zur Entwicklung der erneuerbaren Energien in Deutschland sind die Ergebnisse der Arbeitsgruppe Erneuerbare Energien-Statistik (AGEE-Stat), die im Auftrag des BMWi die Bilanz der erneuerbaren Energien fuer Deutschland erarbeitet. Die hier veroeffentlichten Daten stellen eine Momentaufnahme mit Redaktionsschluss August 2016 dar - sie haben insbesondere fuer das Jahr 2016 an einigen Stellen noch vorlaeufigen Charakter. Parallel werden auf den Internetseiten des BMWi aktuelle Zeitreihen zur Entwicklung der erneuerbaren Energien in Deutschland seit dem Jahr 1990 sowie vielfaeltige Schaubilder veroeffentlicht

Promising energy converters for the next century. Fuel cells for cogeneration systems; Aussichtsreicher Energiewandler fuers naechste Jahrhundert. Brennstoffzelle fuer Kraft-Waerme-Kopplung

Energy Technology Data Exchange (ETDEWEB)

Hilscher, G

1996-02-16

First there is a report on experience with phosphoric acid fuel cell plants (PAFC), which the operators used in a 200 kW plant of Onsi (HEAG, Ruhrgas AG, Thyssengas AG) and a 79 kW plant of Kinetics Technology (Solar-Wasserstoff Bayern GmbH). After this, the present state of development of oxide ceramic high temperature fuel cells (SOFC) and polymer electrolyte diaphragm fuel cells (PEMFC) is briefly described. (MM) [Deutsch] Zuerst wird ueber Erfahrungen mit Phosphorsaeure-Brennstoffzellen-Anlagen (PAFC) berichtet, die die Betreiber einer 200 kW-Anlage von Onsi (HEAG, Ruhrgas AG, Thyssengas AG) und einer 79 kW-Anlage von Kinetics Technology (Solar-Wasserstoff-Bayern GmbH) hatten. Danach wird kurz der derzeitige Stand der Entwicklung bei den oxidkeramischen Hochtemperaturbrennstoffzellen (SOFC) und Polymer-Elektrolyt-Membran-Brennstoffzellen (PEMFC) wiedergegeben. (MM)

Hydrogen as a renewable and sustainable solution in reducing global fossil fuel consumption

International Nuclear Information System (INIS)

Midilli, Adnan; Dincer, Ibrahim

2008-01-01

In this paper, hydrogen is considered as a renewable and sustainable solution for reducing global fossil fuel consumption and combating global warming and studied exergetically through a parametric performance analysis. The environmental impact results are then compared with the ones obtained for fossil fuels. In this regard, some exergetic expressions are derived depending primarily upon the exergetic utilization ratios of fossil fuels and hydrogen: the fossil fuel based global waste exergy factor, hydrogen based global exergetic efficiency, fossil fuel based global irreversibility coefficient and hydrogen based global exergetic indicator. These relations incorporate predicted exergetic utilization ratios for hydrogen energy from non-fossil fuel resources such as water, etc., and are used to investigate whether or not exergetic utilization of hydrogen can significantly reduce the fossil fuel based global irreversibility coefficient (ranging from 1 to +∞) indicating the fossil fuel consumption and contribute to increase the hydrogen based global exergetic indicator (ranging from 0 to 1) indicating the hydrogen utilization at a certain ratio of fossil fuel utilization. In order to verify all these exergetic expressions, the actual fossil fuel consumption and production data are taken from the literature. Due to the unavailability of appropriate hydrogen data for analysis, it is assumed that the utilization ratios of hydrogen are ranged between 0 and 1. For the verification of these parameters, the variations of fossil fuel based global irreversibility coefficient and hydrogen based global exergetic indicator as the functions of fossil fuel based global waste exergy factor, hydrogen based global exergetic efficiency and exergetic utilization of hydrogen from non-fossil fuels are analyzed and discussed in detail. Consequently, if exergetic utilization ratio of hydrogen from non-fossil fuel sources at a certain exergetic utilization ratio of fossil fuels increases

Vanadium in fuel oil - a new solution

Energy Technology Data Exchange (ETDEWEB)

Czech, N. [Siemens, Muelheim (Germany); Finckh, H. [Siemens, Erlangen (Germany)

1998-11-01

Hot corrosion of the hot-gas-path components due to vanadium contamination is one of the hazards associated with heavy residual oil combustion in heavy-duty gas turbines. This economically attractive oil combustion process has benefited from the recently developed vanadium inhibition technique, which is currently being tested at the Valladolid 220 MWe combined cycle plant in Mexico. The method uses atomization of a dilute aqueous solution of Epsom salt (MgSO{sub 7},7H{sub 2}O) into very small droplets which are then injected onto the flame where intensive mixing takes place. The successful use of this new technique promises extended operating periods between cleanup operations, and cost reductions from the use of inexpensive materials, as well as the ability to operate advanced gas turbines on difficult fuels, not previously feasible. (UK)

Technical and economic aspects of fuel cell applications in space HVAC systems; Technische und wirtschaftliche Aspekte zum Einsatz von Brennstoffzellen in der Gebaeudeversorgung

Energy Technology Data Exchange (ETDEWEB)

Handke, J; Handschin, E

1999-12-31

There are two different types of fuel cells for small-scale applications, li.e. polymer electrolyte membrane fuel cells (PEMFC) and high-termperature fuel cells with ceramic solid electrolytes (SOFC). Both types of fuel cells have different advantages and shortcomings. One of the main problems, however, is the fact that research is still going on and that commercial fuel cell systems for space HVAC applications are still not available. (orig.) [Deutsch] Nach dem heutigen Stand werden zwei unterschiedliche Brennstoffzellen-Typen zum Einsatz in Kleinanlagen entwickelt. Neben der zu Klasse der Niedertemperatur-Brennstoffzellen gehoerenden Polymer-Elektrolyt-Membran-Brennstoffzelle (PEMFC) ist dies die Hochtemperatur-Brennstoffzelle auf der Basis eines keramischen Festelektrolyten (SOFC). Beide Brennstoffzellen-Typen haben unterschiedliche Vor- und Nachteile fuer den Einsatz zur Gebaeudeversorgung. Eines der Hauptprobleme, das allerdings beide Zellentypen gemeinsam haben, besteht in der noch nicht abgeschlossenen Entwicklung und - daraus resultierend - der fehlenden kommerziellen Verfuegbarkeit im Bereich der Gebaeudeversorgung. (orig./MM)

A method for recovering and separating palladium, technetium, rhodium and ruthenium contained in solutions resulting from nuclear fuel recycling

International Nuclear Information System (INIS)

Moore, R.H.

1974-01-01

The invention relates to a method for recovering and separating technetium and metals of the platinum group, i.e. palladium, rhodium and ruthenium existing as fission products. The method according to the invention is characterized by contacting a residuary acid aqueous solution provided by nuclear fuel recycling with successive carbon beds which have adsorbed different chelating agents specific for the metals to be recovered in order that said metals be selectively chelated and extracted from the solution. This method is suitable for recovering the above metals from solutions provided by reprocessing spent fuels [fr

Cost and Fuel Efficient SCR-only Solution for post-2010 HD Emission Standards

NARCIS (Netherlands)

Cloudt, R.P.M.; Willems, F.P.T.; Heijden, van der P.

2009-01-01

A promising SCR-only solution is presented to meetpost-2010 NOx emission targets for heavy dutyapplications. The proposed concept is based on anengine from a EURO IV SCR application, which isconsidered optimal with respect to fuel economy andcosts. The addition of advanced SCR after

Fuel effect on solution combustion synthesis of Co(Cr,Al)2O4 pigments

International Nuclear Information System (INIS)

Gilabert, J.; Palacios, M.D.; Sanz, V.; Mestre, S.

2017-01-01

The fuel effect on the synthesis of a ceramic pigment with a composition CoCr2−2ΨAl2ΨO4 (0≤Ψ≤1) by means of solution combustion synthesis process (SCS) has been studied. Three different fuels were selected to carry out the synthesis (urea, glycine and hexamethylentetramine (HMT)). Highly foamy pigments with very low density were obtained. Fd-3m spinel-type structure was obtained in all the experiments. Nevertheless, crystallinity and crystallite size of the spinels show significant differences with composition and fuel. The use of glycine along with the chromium-richest composition favours ion rearrangement to obtain the most ordered structure. Lattice parameter does not seem to be affected by fuel, although it evolves with Ψ according to Vegard's law. Colouring power in a transparent glaze shows important variations with composition. On the other hand, fuel effect presents a rather low influence since practically the same shades are obtained. However, it exerts certain effect on luminosity (L*). [es

Dry storage technologies: Optimized solutions for spent fuels and vitrified residues

International Nuclear Information System (INIS)

Roland, Vincent; Verdier, Antoine; Sicard, Damien; Neider, Tara

2006-01-01

In many countries, fuel cycle and waste policies influence the way operators organize waste management. These policies help drive progress and improvements in areas such as waste minimization programs, conditioning or industrial transformation before final or intermediate conditioning. The criteria that lead to different choices include economic factors, the presence or absence of a wide range of options such as transport, and reprocessing and recycling policies. The current international trend towards expanding Spent Fuel Interim Dry Storage capabilities goes with an improvement of the performance of the proposed systems which have to accommodate Spent fuel Assemblies characterized by ever increasing burn-up, fissile isotopes contents, thermal releases, and total inventory. Due to heterogeneous worldwide reactor pools and specific local constraints the proposed solutions have also to cope with a wide variety of fuel design. The Spent Fuel Assemblies stored temporarily for cooling may have to be transported either to reprocessing facilities or to interim storage facilities before direct disposal; it is the reason why the retrievability, including or not the need of transportation of the proposed systems, is often specified by the utilities for the design of their storage systems and sometimes required by law. In most cases, the producers of spent fuel require a large capacity that is cumulated over many years, each reload at a time. Then the key criterion is maximum modularity. Furthermore, the up front capital costs required for this type of solution has to be attractive for the investor. Two solutions, dual purpose metal casks of the TN TM 24 family or dual purpose or single purpose concrete shielded welded canisters such as NUHOMS R , implemented by COGEMA LOGISTICS, and TRANSNUCLEAR Inc. offer flexibility and modularity and have been adapted also to quite different fuels. Among what influences the choice, we can consider: - In favor of metal casks: Minimal

Möglichkeiten der Umsetzung einer Bildung für nachhaltige Entwicklung unter Verwendung kooperativer Lernformen im Geographieunterricht

OpenAIRE

Stange, Sarah

2016-01-01

„Ohne Nachhaltigkeit gibt es keine gute Zukunft“ betonte die Bildungsstaatssekretärin Cornelia Quennet-Thielen in einem Interview Anfang Oktober (BMBF 2015). Sie erklärte weiter: „Und ohne Bildung bleibt Nachhaltigkeit nur eine Forderung.“ (ebd.) Genau zehn Jahre sind vergangen, seit die Vereinten Nationen die UN-Dekade für Bildung für nachhaltige Entwicklung, kurz BNE, ausriefen. Der Leitgedanken der Nachhaltigkeit sollte über die Bildung Eingang in die Alltagswelten finden. Nun ist die UN-D...

Acid in perchloroethylene scrubber solutions used in HTGR fuel preparation processes. Analytical chemistry studies

International Nuclear Information System (INIS)

Lee, D.A.

1979-02-01

Acids and corrosion products in used perchloroethylene scrubber solutions collected from HTGR fuel preparation processes have been analyzed by several analytical methods to determine the source and possible remedy of the corrosion caused by these solutions. Hydrochloric acid was found to be concentrated on the carbon particles suspended in perchloroethylene. Filtration of carbon from the scrubber solutions removed the acid corrosion source in the process equipment. Corrosion products chemisorbed on the carbon particles were identified. Filtered perchloroethylene from used scrubber solutions contained practically no acid. It is recommended that carbon particles be separated from the scrubber solutions immediately after the scrubbing process to remove the source of acid and that an inhibitor be used to prevent the hydrolysis of perchloroethylene and the formation of acids

Solutions obtained to international heat transfer benchmarking problems for nuclear fuel casks using Q/TRAN

International Nuclear Information System (INIS)

Sanchez, L.C.

1987-02-01

In 1985 Sandia National Laboratories participated in the Nuclear Energy Agency Committee on Reactor Physics (NEACRP) Specialists' Meeting on Heat Transfer Assessment of Transportation Packages. The objective of the meeting was to establish a set of model problems for use in comparing the performance of thermal analysis computer codes that may be used in the design of nuclear fuel shipping casks. The selected problems are to be used to compare code results for the thermal phenomena of conduction, convection, and radiation in cask-like problems. Two model problems were used in this study. The first problem required the determination of the steady-state temperatures of a 16 x 16 array of heated and unheated pins (representing fuel and control rod positions) of a simulated PWR fuel assembly. The second problem required the determination of transient temperatures of a finned surface (representing the external surface of a cask) subjected to an internal heat flux and to an external engulfing fire. Solutions to the problems were obtained with the code ''Q/TRAN.'' Solutions and descriptions of the necessary modeling techniques are given in this report

Mesoporous yttria-zirconia and metal-yttria-zirconia solid solutions for fuel cells

Energy Technology Data Exchange (ETDEWEB)

Mamak, M.; Coombs, N.; Ozin, G. [Toronto Univ., ON (Canada). Dept. of Chemistry

2000-02-03

A new class of binary mesoporous yttria-zirconia (YZ) and ternary mesoporous metal-YZ materials (M = electroactive Ni/Pt) is presented here that displays the highest surface area of any known form of yttria-stabilized zirconia. These mesoporous materials form as solid solutions and retain their structural integrity to 800 C, which bodes well for their possible utilization in fuel cells. (orig.)

Cost and fuel efficient SCR-only solution for post-2010 HD emission standards

NARCIS (Netherlands)

Cloudt, R.P.M.; Willems, F.P.T.; Heijden, P.V.A.M. van der

2009-01-01

A promising SCR-only solution is presented to meet post-2010 NOx emission targets for heavy duty applications. The proposed concept is based on an engine from a EURO IV SCR application, which is considered optimal with respect to fuel economy and costs. The addition of advanced SCR after treatment

Underestimation of nuclear fuel burnup – theory, demonstration and solution in numerical models

Directory of Open Access Journals (Sweden)

Gajda Paweł

2016-01-01

Full Text Available Monte Carlo methodology provides reference statistical solution of neutron transport criticality problems of nuclear systems. Estimated reaction rates can be applied as an input to Bateman equations that govern isotopic evolution of reactor materials. Because statistical solution of Boltzmann equation is computationally expensive, it is in practice applied to time steps of limited length. In this paper we show that simple staircase step model leads to underprediction of numerical fuel burnup (Fissions per Initial Metal Atom – FIMA. Theoretical considerations indicates that this error is inversely proportional to the length of the time step and origins from the variation of heating per source neutron. The bias can be diminished by application of predictor-corrector step model. A set of burnup simulations with various step length and coupling schemes has been performed. SERPENT code version 1.17 has been applied to the model of a typical fuel assembly from Pressurized Water Reactor. In reference case FIMA reaches 6.24% that is equivalent to about 60 GWD/tHM of industrial burnup. The discrepancies up to 1% have been observed depending on time step model and theoretical predictions are consistent with numerical results. Conclusions presented in this paper are important for research and development concerning nuclear fuel cycle also in the context of Gen4 systems.

Considerations in modelling the melting of fuel containing fission products and solute oxides

International Nuclear Information System (INIS)

Akbari, F.; Welland, M.J.; Lewis, B.J.; Thompson, W.T.

2005-01-01

It is well known that the oxidation of a defected fuel element by steam gives rise to an increase in O/U ratio with a consequent lowering of the incipient melting temperature. Concurrently, the hyperstoichiometry reduces the thermal conductivity thereby raising the centerline fuel pellet temperature for a fixed linear power. The development of fission products soluble in the UO 2 phase or, more important, the deliberate introduction of additive oxides in advanced CANDU fuel bundle designs further affects and generally lowers the incipient melting temperature. For these reasons, the modeling of the molten (hyperstoichiometric) UO 2 phase containing several solute oxides (ZrO 2 , Ln 2 O 3 and AnO 2 ) is advancing in the expectation of developing a moving boundary heat and mass transfer model aimed at better defining the limits of safe operating practice as burnup advances. The paper describes how the molten phase stability model is constructed. The redistribution of components across the solid-liquid interface that attends the onset of melting of a non-stoichiometric UO 2 containing several solutes will be discussed. The issues of how to introduce boundary conditions into heat transfer calculations consistent with the requirements of the Phase Rule will be addressed. The Stefan problem of a moving boundary associated with the solid/liquid interface sets this treatment apart from conventional heat and mass transfer problems. (author)

[St. Petersburg und Livland - und die Entwicklung der estnischen Literatur : Anton Schiefner (1817-1879) und Friedrich R. Kreutzwald (1803-1882) im Briefwechsel (1853-1879)] / Felix Köther

Index Scriptorium Estoniae

Köther, Felix

2015-01-01

Arvustus: St. Petersburg und Livland - und die Entwicklung der estnischen Literatur : Anton Schiefner (1817-1879) und Friedrich R. Kreutzwald (1803-1882) im Briefwechsel (1853-1879) / bearbeitet von Hartmut Walravens. Wiesbaden : Harrassowitz, 2013. (Orientalistik-Bibliographien und Dokumentationen ; Bd. 22)

Study of source term evaluation from fuel solution under simulated nuclear criticality accident in TRACY

International Nuclear Information System (INIS)

Abe, Hitoshi; Tashiro, Shinsuke; Nagai, Hitoshi; Koike, Tadao; Okagawa, Seigo; Murata, Mikio

1999-01-01

In a accident at the dissolver in a reprocessing plant, various fission products and radiolysis gases will be produced in the fuel solution and volatile radioactive nuclides and radiolysis gases and nitrogen oxide will be released into vent-gas spontaneously. Moreover other on-volatile nuclide will be releases as radioactive aerosol (mist) with bursting bubbles at surface of the solution. Therefore quantitative estimation of release and transport behavior of the radioactive material from solution as source term is very important. TRACY is a transient criticality experimental facility for studying the transient criticality characteristics of low enriched uranium. In this paper, experiment methods and results about the release behavior of the hydrogen, radioactive aerosol and iodine species from the fuel solutions are reported. As the results of the experiments, release patterns of H 2 , 140 Ba and 131 I could be grasped. Concentrations of H 2 in the vent-gas and 140 Ba in the gas phase in the core tank attained to the peak just after the transient criticality and decreased exponentially with time. On the other hand, concentrations of 131 I in the gas phase of the tank began to increase with a time lag of several minutes from the transient criticality and attained approximately constant values. (J.P.N.)

Power electronics for local fuel cell/-battery plants; Leistungselektronik fuer dezentrale Brennstoffzellen/-Batterieanlagen

Energy Technology Data Exchange (ETDEWEB)

Krykunov, Oleksandr

2009-10-13

With their high efficiency and modular structure, fuel cells are an attractive option for decentral power supply. An important component of decentral power supply systems is the power-electronic control element for supply of electric power from the fuel cell to the three-phase electricity grid. Control elements can be constructed of a unidirectional DC/DC converter with a current inverter connnected in series. The investigation focused on the development of the DC/DC converter with minimum constructional and control requirements and optimum adaption of the DC/DC converter to the characteristics of the fuel cell. (orig.) [German] Die Brennstoffzelle stellt mit ihrem hohen Wirkungsgrad und ihrem modularen Aufbau eine attraktive Option fuer die Verwendung in einem dezentralen Energieversorgungssystem dar. Eine wichtige Komponente des dezentralen Energieversorgungssystems sind die leistungselektronischen Stellglieder fuer die Einspeisung der elektrischen Energie aus der Brennstoffzelle in das dreiphasige Netz. Die leistungselektronischen Stellglieder koennen aus einem undirektionalen DC/DC-Wandler und einem nachgeschalteten Wechselrichter realisiert werden. Die Entwicklung des DC/DC-Wandlers mit einem moeglichst geringeren Bauelemente- und Steuerungsaufwand fuer diese leistungselektronischen Stellglieder und die Anpassung des DC/DC-Wandlers an die Eigenschaften der Brennstoffzelle war das Ziel dieser Arbeit. (orig.)

Decentralized hydrogen production for fuel cells; Dezentrale Wasserstoffproduktion fuer Brennstoffzellen. Entwicklung eines Kompaktreformers fuer erdgasbetriebene Brennstoffzellenheizgeraete

Energy Technology Data Exchange (ETDEWEB)

Trimis, Dimosthenis; Anger, Stephan [Technische Univ. Bergakademie Freiberg (Germany). Lehrstuhl fuer Gas- und Waermetechnische Anlagen; Otto, Bert; Nitzsche, Joerg [DBI - Gastechnologisches Institut gGmbH Freiberg (Germany); Grosser, Katrin [Riesaer Brennstoffzellentechnik GmbH, Glaubitz (Germany); Krause, Hartmut [DBI - Gastechnologisches Institut gGmbH Freiberg (Germany); DBI Gas- und Umwelttechnik GmbH, Leipzig (Germany)

2012-07-01

The reconstruction of energy-supply towards more sustainability has reached the boiler rooms. More and more innovative heating systems come into the market like heat pumps, solar-thermal applications and last but not least decentralized cogeneration plants like Sterling- or internal combustion engines. With fuel cells another high-performance technology is introduced, which comes along with especially high electrical efficiencies at low acoustic and noxious emissions. Efficient fuel processing systems are needed as an essential component of such devices. (orig.)

Fuel solution criticality accident studies with the SILENE reactor: phenomenology, consequences and simulated intervention

International Nuclear Information System (INIS)

Barbry, F.

1984-01-01

After defining the content and the objectives of criticality accident studies, the SILENE reactor, a means of studying fuel solution criticality accidents, is presented. Information obtained from the CRAC and SILENE experimental programs are then presented; they concern power excursion phenomenology, radiological consequences, and finally guide-lines for current and future programs

Mixture of fuels for solution combustion synthesis of porous Fe{sub 3}O{sub 4} powders

Energy Technology Data Exchange (ETDEWEB)

Parnianfar, H.; Masoudpanah, S.M., E-mail: masoodpanah@iust.ac.ir; Alamolhoda, S.; Fathi, H.

2017-06-15

Highlights: • Mixture of glycine and urea fuels was applied for solution combustion synthesis of Fe3O4 powders. • The phase and crystallite size of the as-combusted powders depends on the fuel to oxidant ratio (ϕ). • The maximum density (0.033 cm{sup 3}/g) was observed for the as-combusted powders at ϕ = 1. • The highest Ms of 75.5 emu/g and the lowest Hc of 84 Oe were achieved at ϕ = 1. - Abstract: The solution combustion synthesis of porous magnetite (Fe{sub 3}O{sub 4}) powders by a mixture of glycine and urea fuels was investigated concerning the thermodynamic aspects and powder characteristics. The adiabatic combustion temperature and combusted species were thermodynamically calculated as a function of the fuel to oxidant molar ratio (ϕ). The combustion behavior, phase evolution, porous structure and magnetic properties were characterized by thermal analysis, X-ray diffractometry, N{sub 2} adsorption–desorption, electron microscopy and vibrating sample magnetometry techniques. Nearly single phase Fe{sub 3}O{sub 4} powders were synthesized by the mixture of fuels at ϕ values of 0.75 and 1. The as-combusted Fe{sub 3}O{sub 4} powders at ϕ = 1 exhibited porous structure with the specific surface area of 83.4 m{sup 2}/g. The highest saturation magnetization of 75.5 emu/g and the lowest coercivity of 84 Oe were achieved at ϕ = 1, due to the high purity and large crystallite size, inducing from the highest adiabatic combustion temperature.

Mass transfer in fuel cells. [electron microscopy of components, thermal decomposition of Teflon, water transport, and surface tension of KOH solutions

Science.gov (United States)

Walker, R. D., Jr.

1973-01-01

Results of experiments on electron microscopy of fuel cell components, thermal decomposition of Teflon by thermogravimetry, surface area and pore size distribution measurements, water transport in fuel cells, and surface tension of KOH solutions are described.

Fuels Containing Methane of Natural Gas in Solution

Science.gov (United States)

Sullivan, Thomas A.

2004-01-01

While exploring ways of producing better fuels for propulsion of a spacecraft on the Mars sample return mission, a researcher at Johnson Space Center (JSC) devised a way of blending fuel by combining methane or natural gas with a second fuel to produce a fuel that can be maintained in liquid form at ambient temperature and under moderate pressure. The use of such a blended fuel would be a departure for both spacecraft engines and terrestrial internal combustion engines. For spacecraft, it would enable reduction of weights on long flights. For the automotive industry on Earth, such a fuel could be easily distributed and could be a less expensive, more efficient, and cleaner-burning alternative to conventional fossil fuels. The concept of blending fuels is not new: for example, the production of gasoline includes the addition of liquid octane enhancers. For the future, it has been commonly suggested to substitute methane or compressed natural gas for octane-enhanced gasoline as a fuel for internal-combustion engines. Unfortunately, methane or natural gas must be stored either as a compressed gas (if kept at ambient temperature) or as a cryogenic liquid. The ranges of automobiles would be reduced from their present values because of limitations on the capacities for storage of these fuels. Moreover, technical challenges are posed by the need to develop equipment to handle these fuels and, especially, to fill tanks acceptably rapidly. The JSC alternative to provide a blended fuel that can be maintained in liquid form at moderate pressure at ambient temperature has not been previously tried. A blended automotive fuel according to this approach would be made by dissolving natural gas in gasoline. The autogenous pressure of this fuel would eliminate the need for a vehicle fuel pump, but a pressure and/or flow regulator would be needed to moderate the effects of temperature and to respond to changing engine power demands. Because the fuel would flash as it entered engine

Hydrogen Fuel Cells: Part of the Solution

Science.gov (United States)

Busby, Joe R.; Altork, Linh Nguyen

2010-01-01

With the decreasing availability of oil and the perpetual dependence on foreign-controlled resources, many people around the world are beginning to insist on alternative fuel sources. Hydrogen fuel cell technology is one answer to this demand. Although modern fuel cell technology has existed for over a century, the technology is only now becoming…

Development with DMU. Options in the modern product life cycle; Entwicklung mit DMU. Moeglichkeiten im modernen Produktlebenszyklus

Energy Technology Data Exchange (ETDEWEB)

Hoehn, H.; Moser, H. [Competent Engineering GmbH, Graz (Austria)

2005-02-01

In this contribution, the Graz-based development company Competent Engineering outlines the advantages of digital mock-ups for efficient product development. The focus is on a uniform product and data structure that is to ensure early availability of DMU for all stages of the product life cycle. (orig.) [German] Der Grazer Entwicklungsdienstleister Competent Engineering beschreibt in diesem Beitrag anhand der Entwicklung eines Ottomotors, welche Vorteile der Einsatz von Digital Mock-Ups fuer eine effiziente Produktentwicklung hat. Besondere Bedeutung hat dabei eine moeglichst durchgaengige Produkt- und Datenstruktur, um eine fruehe Verfuegbarkeit der DMUs fuer alle Bereiche innerhalb des Produktlebenszyklus zu ermoeglichen. (orig.)

Problems and solutions of the spent nuclear fuel (SNF) at Kozloduy NPP

International Nuclear Information System (INIS)

Jordanov, J.

2003-01-01

There are two options concerning spent nuclear fuel: to return it back to Russia for reprocessing or to store it on the site until we decide what to do with it. In both options prior to the shutting down of each reactor the Spent Fuel Pool thereto should be vacated (the filling in of the equipment at present is illustrated) and the Spent Fuel Storage Facility (SFSF) should also be vacated after the stop of the last nuclear facility on the site in order to be reequipped for permanent storage of the highly active wastes which will be returned in the country, if we submit the fuel for reprocessing; or of SNF, if we decide to leave them ultimately in Bulgaria. The difference is mainly in the quantities which will permanently remain here, respectively the volumes required for their storage and the funds necessary for the implementation of the processes. The pool volumes filling in both variants is also illustrated and the SFSF will be filled by 2008, if no fuel is transported.Costs of the SNF transport to Russia and investment costs of dry storage of SNF from pools 1 - 4 are present. The costs are visibly lower compared to those in the case of return of the fuel. However, these are only investments for construction and equipment of the buildings and storage containers. The costs related to their servicing are not included, and it should be taken into account that in approximately 50 years we will have to seek solution for their permanent storage. Despite the material costs to be incurred now for the implementation of the option with the return of the fuel, this is the more worthy way to resolve the problem. In accordance with the ethic principles in the nuclear energy, the burdens arising as a result of the use of nuclear facilities should be covered by the generation consuming the benefits from it

Resin bead-thermal ionization mass spectrometry for determination of plutonium concentration in irradiated fuel dissolver solution

International Nuclear Information System (INIS)

Paul, Sumana; Shah, R.V.; Aggarwal, S.K.; Pandey, A.K.

2015-01-01

Determination of isotopic composition (IC) and concentration of plutonium (Pu) is necessary at various stages of nuclear fuel cycle which involves analysis of complex matrices like dissolver solution of irradiated fuel, nuclear waste stream etc. Mass spectrometry, e.g. thermal ionization mass spectrometry (TIMS) and inductively coupled plasma mass spectrometry (ICP-MS) are commonly used for determination of IC and concentration of plutonium. However, to circumvent matrix interferences, efficient separation as well as preconcentration of Pu is required prior to mass spectrometric analysis. Purification steps employing ion-exchange resins are widely used for the separation of Pu from dissolver solution or from mixture of other actinides e.g. U, Am. However, an alternative way is to selectively preconcentrate Pu on a resin bead, followed by direct loading of the bead on the filament of thermal ionization mass spectrometer

An intercomparison experiment on isotope dilution thermal ionisation mass spectrometry using plutonium-239 spike for the determination of plutonium concentration in dissolver solution of irradiated fuel

International Nuclear Information System (INIS)

Aggarwal, S.K.; Shah, P.M.; Saxena, M.K.; Jain, H.C.; Gurba, P.B.; Babbar, R.K.; Udagatti, S.V.; Moorthy, A.D.; Singh, R.K.; Bajpai, D.D.

1996-01-01

Determination of plutonium concentration in the dissolver solution of irradiated fuel is one of the key measurements in the nuclear fuel cycle. This report presents the results of an intercomparison experiment performed between Fuel Chemistry Division (FCD) at BARC and PREFRE, Tarapur for determining plutonium concentration in dissolver solution of irradiated fuel using 239 Pu spike in isotope dilution thermal ionisation mass spectrometry (ID-TIMS). The 239 Pu spike method was previously established at FCD as viable alternative to the imported enriched 242 Pu or 244 Pu; the spike used internationally for plutonium concentration determination by IDMS in dissolver solution of irradiated fuel. Precision and accuracy achievable for determining plutonium concentration are compared under the laboratory and the plant conditions using 239 Pu spike in IDMS. For this purpose, two different dissolver solutions with 240 Pu/ 239 Pu atom ratios of about 0.3 and 0.07 corresponding, respectively, to high and low burn-up fuels, were used. The results of the intercomparison experiment demonstrate that there is no difference in the precision values obtained under the laboratory and the plant conditions; with mean precision values of better than 0.2%. Further, the plutonium concentration values determined by the two laboratories agreed within 0.3%. This exercise, therefore, demonstrates that ID-TIMS method using 239 Pu spike can be used for determining plutonium concentration in dissolver solution of irradiated fuel, under the plant conditions. 7 refs., 8 tabs

Safety of interim storage solutions of used nuclear fuel during extended term

Energy Technology Data Exchange (ETDEWEB)

Shelton, C.; Bader, S.; Issard, H.; Arslan, M. [AREVA, 7135 Minstrel Way, Suite 300 Columbia, MD 21045 (United States)

2013-07-01

In 2013, the total amount of stored used nuclear fuel (UNF) in the world will reach 225,000 T HM. The UNF inventory in wet storage will take up over 80% of the available total spent fuel pool (SFP) capacity. Interim storage solutions are needed. They give flexibility to the nuclear operators and ensure that nuclear reactors continue to operate. However, we need to keep in mind that they are also an easy way to differ final decision and implementation of a UNF management approach (recycling or final disposal). In term of public perception, they can have a negative impact overtime as it may appear that nuclear industry may have significant issues to resolve. In countries lacking an integrated UNF management approach, the UNF are being discharged from the SFPs to interim storage (mostly to dry storage) at the same rate as UNF is being discharged from reactors, as the SFPs at the reactor sites are becoming full. This is now the case in USA, Taiwan, Switzerland, Spain, South Africa and Germany. For interim storage, AREVA has developed different solutions in order to allow the continued operation of reactors while meeting the current requirements of Safety Authorities: -) Dry storage canisters on pads, -) Dual-purpose casks (dry storage and transportation), -) Vault dry storage, and -) Centralized pool storage.

Research program and uses of the solution fueled reactor SILENE

International Nuclear Information System (INIS)

Barbry, F.; Ratel, R.

1985-09-01

Designed and operated by the Nuclear Protection and Safety Institute of the CEA, SILENE is an original small sized reactor fueled with an uranyl nitrate solution. The reactor is capable to operate in three modes: ''Pulse'' operation (high power levels up to 1000 Megawatts during several millisecond), ''Free evolution'' operation (simulation of criticality accident excursions), ''Steady state'' operation in a power range of 0.01 W to 1 kW. The core can be surrounded by appropriate shields (lead, polyethylene) to vary the leakage radiations and the gamma to neutron dose ratio. It's possible to insert in the central cavity of the annular core vessel some capsules, devices or samples to be submitted to very high radiations levels. The research activities are mainly devoted towards nuclear safety studies: the criticality accident studies, and the behavior of oxide fuels under transient conditions. Some examples of tests are presented. As to other applications of the SILENE facility, the main studies now in progress deal with: designing and calibration of Health physics intrumentation, neutron and gamma dosimetry, and, radiobiology. Once the characteristics of radiation field are qualified by calculations and experimental techniques, SILENE will be proposed as a reference source [fr

Analytical solutions for the temperature field in a 2D incompressible inviscid flow through a channel with walls of solid fuel

Directory of Open Access Journals (Sweden)

Sorin BERBENTE

2011-12-01

Full Text Available A gas (oxidizer flows between two parallel walls of solid fuel. A combustion is initiated: the solid fuel is vaporized and a diffusive flame occurs. The hot combustion products are submitted both to thermal diffusion and convection. Analytical solutions can be obtained both for the velocity and temperature distributions by considering an equivalent mean temperature where the density and the thermal conductivity are evaluated. The main effects of heat transfer are due to heat convection at the flame. Because the detailed mechanism of the diffusion flame is not introduced the reference chemical reaction is the combustion of premixed fuel with oxidizer in excess. In exchange the analytical solution is used to define an ideal quasi-uniform combustion that could be realized by an n adequate control. The given analytical closed solutions prove themselves flexible enough to adjust the main data of some existing experiments and to suggest new approaches to the problem.

Mixture of fuels for solution combustion synthesis of porous Fe3O4 powders

Science.gov (United States)

Parnianfar, H.; Masoudpanah, S. M.; Alamolhoda, S.; Fathi, H.

2017-06-01

The solution combustion synthesis of porous magnetite (Fe3O4) powders by a mixture of glycine and urea fuels was investigated concerning the thermodynamic aspects and powder characteristics. The adiabatic combustion temperature and combusted species were thermodynamically calculated as a function of the fuel to oxidant molar ratio (ϕ). The combustion behavior, phase evolution, porous structure and magnetic properties were characterized by thermal analysis, X-ray diffractometry, N2 adsorption-desorption, electron microscopy and vibrating sample magnetometry techniques. Nearly single phase Fe3O4 powders were synthesized by the mixture of fuels at ϕ values of 0.75 and 1. The as-combusted Fe3O4 powders at ϕ = 1 exhibited porous structure with the specific surface area of 83.4 m2/g. The highest saturation magnetization of 75.5 emu/g and the lowest coercivity of 84 Oe were achieved at ϕ = 1, due to the high purity and large crystallite size, inducing from the highest adiabatic combustion temperature.

Thermometric titration of a free acid and of uranyl in spent fuel element solutions

International Nuclear Information System (INIS)

Zamek, M.; Strafelda, F.

1975-01-01

A method was elaborated of determining nitric acid in the presence of uranyl nitrate in both aqueous and non-aqueous solutions using a pyridine aqueous solution as a titration agent, and of determining excess uranyl after a hydrogen peroxide addition by a further titration using the same agent. Even a hundred-fold excess of magnesium did not disturb the titration. The method is used in operating solution analyses in the extraction fuel reprocessing in the presence of a small amount of plutonium and of fission products. The reproducibility and accuracy of the method varied in the order of tens to units per cent depending on the concentration of components to be determined. The procedure is applicable for test volumes ranging between 0.1 and 10 ml in concentrations of 1 to 10 -3 M. (author)

Development of a BMW flexible fuel vehicle. Entwicklung eines BMW-Fahrzeuges fuer flexiblen Benzin-Methanol-Mischbetrieb

Energy Technology Data Exchange (ETDEWEB)

Muhl, W; Petra, H

1992-02-01

A standard BMW 6-cylinder engine with 4 valves was converted for methanol flexible fuel operation. New performance characteristics of air/fuel mixture and ignition timing were determined for different methanol concentrations (M20, M50, M85). The recognition of the methanol concentration was made by means of a capacitive alcohol sensor and the adaptive Lambda Control. Without any modification of the catalyst the HC emission was reduced about 40% in US-test cycle. The efficiency of M85 was upgraded about 8% under vehicle operation conditions. Under any method concentration the driveability of the car was as well as operated with pure gasoline. Operating with M85 the engine increased torque and power by 11%. (orig.).

A study on the alkalimetric titration with gran plot in noncomplexing media for the determination of free acid in spent fuel solutions

International Nuclear Information System (INIS)

Suh, Moo Yul; Lee, Chang Heon; Sohn, Se Chul; Kim, Jung Suk; Kim, Won Ho; Eom, Tae Yoon

1999-01-01

Based on the study of hydrolysis behaviour of U(VI) ion and major fission product metal ions such as Cs(I), Ce(III), Nd(III), Mo(VI), Ru(II), and Zr(VI) in the titration media, the performance of noncomplexing-alkalimetric titration method for the determination of free acid in the presence of these metal ions was investigated and its results were compared to those from the complexing methods. The free acidities could be determined as low as 0.05 meq in uranium solutions in which the molar ratio of U(VI)/H + was less than 5, when the end-point of titration was estimated by Gran plot. The biases in the determinations were less than ±1% and about +3% respectively for 0.4 meq and 0.05 meq of free acid at the U(VI)/H + molar ratio of up to 5. Applicability of this method to the determination of free acid in spent fuel solutions was confirmed by the analysis of nitric acid content in simulated spent fuel solutions and in a real spent fuel solution

From eco-efficiency in overall sustainable development in enterprises; Von Oekoeffizienz zu nachhaltiger Entwicklung in Unternehmen

Energy Technology Data Exchange (ETDEWEB)

Weizsaecker, E.U. von; Stigson, B; Seiler-Hausmann, J D [eds.

2001-07-01

Eco-efficiency is achieved when goods and services satisfy human needs, increase the quality of life, at prices which are competitive and when environmental impacts and resource intensity are decreased to a degree that they are in accordance with the expected capacities of the Earth. Eco-efficiency is a management approach that allows enterprises to carry out environmental protection measures from a market-oriented point of view. Eco-efficiency shows that ecology and economy do not contradict each other. On the contrary, in combination, they present a gain for enterprises. The motto is: To produce more with less. The WBCSD and its member enterprises have agreed to make economic growth and sustainable development the guideline for their economic entrepreneurial actions. The WBCSD supports the close co-operation of the economy, government and other organizations, as it is only together that we can help sustainable development to achieve a breakthrough. (orig.) [German] Oekoeffizienz ist dann erreicht, wenn Gueter und Dienstleistungen die menschlichen Beduerfnisse befriedigen, die Lebensqualitaet erhoehen und wettbewerbsfaehige Preise aufweisen, und die oekologischen Auswirkungen und die Ressourcenintensitaet waehrend des Lebenszyklus soweit verringert werden, dass eine Uebereinstimmung mit der voraussichtlichen Belastbarkeit der Erde besteht. Oekoeffizienz steht fuer einen Managementansatz, der Unternehmen erlaubt, Umweltschutzmassnahmen unter Marktgesichtspunkten durchzufuehren. Mit Oekoeffizienz wird zum Ausdruck gebracht, dass Oekonomie und Oekologie sich nicht ausschliessen, sondern in Kombination einen Gewinn fuer Unternehmen darstellen. Das Motto lautet: Mehr mit weniger produzieren. Der WBCSD und seine Mitgliedsunternehmen haben sich darauf verstaendigt, ihr Handeln von den Prinzipien des oekonomischen Wachstums und der nachhaltigen Entwicklung leiten zu lassen. Der WBCSD unterstuetzt die enge Zusammenarbeit von Wirtschaft, Staat und anderen Organisationen

Bildung für eine nachhaltige Entwicklung. Bericht der BLK an die Regierungschefs von Bund und Ländern zur Umsetzung des Orientierungsrahmens

OpenAIRE

2001-01-01

Der Orientierungsrahmen "Bildung für eine nachhaltige Entwicklung" wurde 1998 durch die Bund-Länder-Kommission für Bildungsplanung und Forschungsförderung (BLK) beschlossen. In dem vorliegenden Dokument wird auf der Grundlage einer Umfrage der BLK-Geschäftsstelle bei den Kultus- und Wissenschaftsministerien über seine Umsetzung berichtet. Der Bericht gliedert sich wie folgt: 1. Rechtliche und politische Grundlagen sowie landesspezifische Initiativen/Programme einer Bildung für nachhaltige Ent...

Thermoelastic analysis of spent fuel and high level radioactive waste repositories in salt. A semi-analytical solution

International Nuclear Information System (INIS)

St John, C.M.

1977-04-01

An underground repository containing heat generating, High Level Waste or Spent Unreprocessed Fuel may be approximated as a finite number of heat sources distributed across the plane of the repository. The resulting temperature, displacement and stress changes may be calculated using analytical solutions, providing linear thermoelasticity is assumed. This report documents a computer program based on this approach and gives results that form the basis for a comparison between the effects of disposing of High Level Waste and Spent Unreprocessed Fuel

Improving the electrocatalytic properties of Pd-based catalyst for direct alcohol fuel cells: effect of solid solution.

Science.gov (United States)

Wen, Cuilian; Wei, Ying; Tang, Dian; Sa, Baisheng; Zhang, Teng; Chen, Changxin

2017-07-07

The tolerance of the electrode against the CO species absorbed upon the surface presents the biggest dilemma of the alcohol fuel cells. Here we report for the first time that the inclusion of (Zr, Ce)O 2 solid solution as the supporting material can significantly improve the anti-CO-poisoning as well as the activity of Pd/C catalyst for ethylene glycol electro-oxidation in KOH medium. In particular, the physical origin of the improved electrocatalytic properties has been unraveled by first principle calculations. The 3D stereoscopic Pd cluster on the surface of (Zr, Ce)O 2 solid solution leads to weaker Pd-C bonding and smaller CO desorption driving force. These results support that the Pd/ZrO 2 -CeO 2 /C composite catalyst could be used as a promising effective candidate for direct alcohol fuel cells application.

Proton exchange membrane fuel cell for cooperating households: A convenient combined heat and power solution for residential applications

International Nuclear Information System (INIS)

Cappa, Francesco; Facci, Andrea Luigi; Ubertini, Stefano

2015-01-01

In this paper we compare the technical and economical performances of a high temperature proton exchange membrane fuel cell with those of an internal combustion engine for a 10 kW combined heat and power residential application. In a view of social innovation, this solution will create new partnerships of cooperating families aiming to reduce the energy consumption and costs. The energy system is simulated through a lumped model. We compare, in the Italian context, the total daily operating cost and energy savings of each system with respect to the separate purchase of electricity from the grid and production of the thermal energy through a standard boiler. The analysis is carried out with the energy systems operating with both the standard thermal tracking and an optimized management. The latter is retrieved through an optimization methodology based on the graph theory. We show that the internal combustion engine is much more affected by the choice of the operating strategy with respect to the fuel cell, in terms long term profitability. Then we conduct a net present value analysis with the aim of evidencing the convenience of using a high temperature proton exchange membrane fuel cell for cogeneration in residential applications. - Highlights: • Fuel cells are a feasible and economically convenient solution for residential CHP. • Control strategy is fundamental for the economical performance of a residential CHP. • Flexibility is a major strength of the fuel cell CHP.

Entwicklung der Reglementierung von 10 MEM-Berufen im Kontext von Bildungsreformen und dem Wandel in der Arbeitswelt: Eine Kurzstudie im Auftrag von LIBS: Eine Kurzstudie im Auftrag von LIBS Industrielle Berufslehren Schweiz, Baden

OpenAIRE

Egg, Maria Esther; Renold, Ursula

2015-01-01

Im Auftrag der LIBS Industrielle Berufslehren Schweiz, hat die KOF die Entwicklung von 10 MEM1-Berufsbildern seit dem ersten Berufsbildungsgesetz dargestellt und diese eingebettet in eine kurze Zusammenfassung der wichtigsten Etappenschritte des Schweizer Berufsbildungssystems.

Study of influence of fuel on dielectric and ferroelectric properties of bismuth titanate ceramics synthesized using solution based combustion technique

International Nuclear Information System (INIS)

Subohi, Oroosa; Malik, M M; Kurchania, Rajnish; Kumar, G S

2015-01-01

The effect of fuel characteristics on the processing and properties of bismuth titanate (BIT) ceramics obtained by solution combustion route using different fuels are reported in this paper. Dextrose, urea and glycine were used as fuel in this study. The obtained bismuth titanate ceramics were characterized by using XRD, SEM at different stages of sample preparation. It was observed that BIT obtained by using dextrose as fuel shows higher dielectric constant and higher remnant polarization due to smaller grain size and lesser c-axis growth as compared to the samples with urea and glycine as fuel. The electrical behavior of the samples with respect to temperature and frequency was also investigated to understand relaxation phenomenon. (paper)

Long-term perspectives of technical and social development in Germany. Visions for research and technology policy; Langfristige Perspektiven technischer und gesellschaftlicher Entwicklung in Deutschland. Visionen fuer die Forschungs- und Technologiepolitik

Energy Technology Data Exchange (ETDEWEB)

Baron, W; Zweck, A

1995-12-01

This publication contains six contributions discussing the medium- and long-term perspectives of technical, social and economic development in Germany. (UA) [Deutsch] Die vorliegende Publikation enthaelt 6 Vortraege, die sich mit mittel- und langfristigen Perspektiven der technischen, sozialen und wirtschaftlichen Entwicklung in Deutschland befassen. (UA)

Dissolving method for nuclear fuel oxide

International Nuclear Information System (INIS)

Tomiyasu, Hiroshi; Kataoka, Makoto; Asano, Yuichiro; Hasegawa, Shin-ichi; Takashima, Yoichi; Ikeda, Yasuhisa.

1996-01-01

In a method of dissolving oxides of nuclear fuels in an aqueous acid solution, the oxides of the nuclear fuels are dissolved in a state where an oxidizing agent other than the acid is present together in the aqueous acid solution. If chlorate ions (ClO 3 - ) are present together in the aqueous acid solution, the chlorate ions act as a strong oxidizing agent and dissolve nuclear fuels such as UO 2 by oxidation. In addition, a Ce compound which generates Ce(IV) by oxidation is added to the aqueous acid solution, and an ozone (O 3 ) gas is blown thereto to dissolve the oxides of nuclear fuels. Further, the oxides of nuclear fuels are oxidized in a state where ClO 2 is present together in the aqueous acid solution to dissolve the oxides of nuclear fuels. Since oxides of the nuclear fuels are dissolved in a state where the oxidizing agent is present together as described above, the oxides of nuclear fuels can be dissolved even at a room temperature, thereby enabling to use a material such as polytetrafluoroethylene and to dissolve the oxides of nuclear fuels at a reduced cost for dissolution. (T.M.)

Fuel cells:

DEFF Research Database (Denmark)

Sørensen, Bent

2013-01-01

A brief overview of the progress in fuel cell applications and basic technology development is presented, as a backdrop for discussing readiness for penetration into the marketplace as a solution to problems of depletion, safety, climate or environmental impact from currently used fossil and nucl......A brief overview of the progress in fuel cell applications and basic technology development is presented, as a backdrop for discussing readiness for penetration into the marketplace as a solution to problems of depletion, safety, climate or environmental impact from currently used fossil...... and nuclear fuel-based energy technologies....

Entwicklung und Evaluierung eines auf dem Stellungsfeldermodell basierenden syntaktischen Annotationsverfahrens für Lernerkorpora innerhalb einer Mehrebenen-Architektur mit Schwerpunkt auf schriftlichen Texten fortgeschrittener Deutschlerner

OpenAIRE

Doolittle, Seanna

2008-01-01

Die Arbeit zeigt exemplarisch die Möglichkeiten, die die Mehrebenen-Korpusarchitektur bei der Annotation von „standard-“ und „nicht standardsprachlichen“ Äußerungen in einem gemeinsamen Korpus bieten. // Konkret beschäftigt sie sich mit der Entwicklung und Evaluierung eines auf dem Stellungsfeldermodell basierenden syntaktischen Annotationsverfahrens für Lernerkorpora, bestehend aus schriftlichen Texten fortgeschrittener Deutschlerner, innerhalb einer Mehrebenen-Architektur. Die Felderannotat...

Bio fuel ash in a road construction: impact on soil solution chemistry.

Science.gov (United States)

Thurdin, R T; van Hees, P A W; Bylund, D; Lundström, U S

2006-01-01

Limited natural resources and landfill space, as well as increasing amounts of ash produced from incineration of bio fuel and municipal solid waste, have created a demand for useful applications of ash, of which road construction is one application. Along national road 90, situated about 20 km west of Sollefteå in the middle of Sweden, an experiment road was constructed with a 40 cm bio fuel ash layer. The environmental impact of the ash layer was evaluated from soil solutions obtained by centrifugation of soil samples taken on four occasions during 2001-2003. Soil samples were taken in the ash layer, below the ash layer at two depths in the road and in the ditch. In the soil solutions, pH, conductivity, dissolved organic carbon (DOC) and the total concentration of cations (metals) and anions were determined. Two years after the application of the ash layers in the test road, the concentrations in the ash layer of K, SO4, Zn, and Hg had increased significantly while the concentration of Se, Mo and Cd had decreased significantly. Below the ash layer in the road an initial increase of pH was observed and the concentrations of K, SO4, Se, Mo and Cd increased significantly, while the concentrations of Cu and Hg decreased significantly in the road and also in the ditch. Cd was the element showing a potential risk of contamination of the groundwater. The concentrations of Ca in the ash layer indicated an ongoing hardening, which is important for the leaching rate and the strength of the road construction.

Nuclear fuel management via fuel quality factor averaging

International Nuclear Information System (INIS)

Mingle, J.O.

1978-01-01

The numerical procedure of prime number averaging is applied to the fuel quality factor distribution of once and twice-burned fuel in order to evolve a fuel management scheme. The resulting fuel shuffling arrangement produces a near optimal flat power profile both under beginning-of-life and end-of-life conditions. The procedure is easily applied requiring only the solution of linear algebraic equations. (author)

A parallel multi-domain solution methodology applied to nonlinear thermal transport problems in nuclear fuel pins

Energy Technology Data Exchange (ETDEWEB)

Philip, Bobby, E-mail: philipb@ornl.gov [Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, TN 37831 (United States); Berrill, Mark A.; Allu, Srikanth; Hamilton, Steven P.; Sampath, Rahul S.; Clarno, Kevin T. [Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, TN 37831 (United States); Dilts, Gary A. [Los Alamos National Laboratory, PO Box 1663, Los Alamos, NM 87545 (United States)

2015-04-01

This paper describes an efficient and nonlinearly consistent parallel solution methodology for solving coupled nonlinear thermal transport problems that occur in nuclear reactor applications over hundreds of individual 3D physical subdomains. Efficiency is obtained by leveraging knowledge of the physical domains, the physics on individual domains, and the couplings between them for preconditioning within a Jacobian Free Newton Krylov method. Details of the computational infrastructure that enabled this work, namely the open source Advanced Multi-Physics (AMP) package developed by the authors is described. Details of verification and validation experiments, and parallel performance analysis in weak and strong scaling studies demonstrating the achieved efficiency of the algorithm are presented. Furthermore, numerical experiments demonstrate that the preconditioner developed is independent of the number of fuel subdomains in a fuel rod, which is particularly important when simulating different types of fuel rods. Finally, we demonstrate the power of the coupling methodology by considering problems with couplings between surface and volume physics and coupling of nonlinear thermal transport in fuel rods to an external radiation transport code.

FIPS: a process for the solidification of fission product solutions using a drum drier. [HTGR fuel reprocessing

Energy Technology Data Exchange (ETDEWEB)

Halaszovich, St.; Laser, M.; Merz, E.; Thiele, D.

1976-08-01

A new process consisting of the steps concentration of the fission product solution, denitration of the solution by addition of formaldehyde, addition of glass-forming additives, drying of the slurry using a drum drier, melting of the dry product in the crucible by rising level in-pot-melting, and off-gas treatment and recovery of nitric acid is under development. A small plant with a capacity of 1 kg glass per hour has been tested in hot cells with fission product solutions from LWR fuel element reprocessing since December 1974. The equipment is very simple to operate and to control. No serious problems arose during operation.

Corrosion studies of thermally sensitised AGR fuel element brace in pH7 and pH9.2 borate solutions

International Nuclear Information System (INIS)

Tyfield, S.P.; Smith, C.A.

1987-04-01

Brace and cladding of AGR fuel elements sensitised in reactor are susceptible to intergranular and crevice corrosion, which may initiate in the pH7 borate pond storage environment of CEGB/SSEB stations. This report considers the benefit in corrosion control that is provided by raising the pond solution pH to 9.2, whilst maintaining the boron level at 1250 gm -3 . The greater corrosion protection provided by pH9.2 solution compared to the pH7 borate solution is demonstrated by a series of tests with non-active laboratory sensitised brace samples exposed to solutions dosed with chloride or sulphate in order to promote localised corrosion. The corrosion tests undertaken consisted of 5000 hour immersions at 32 0 C and shorter term electrochemically monitored experiments (rest potential, impedance, anodic current) generally conducted at 22 0 C. The pH9.2 solution effectively inhibited the initiation of crevice and intergranular corrosion in the presence of low levels of chloride and sulphate, whereas the pH7 solution did not always do so. However, the pH9.2 solution, dosed with 40 gm -3 chloride, failed to suppress fully crevice corrosion initiated in unborated 40 gm -3 chloride solution at 22 0 C. Fluoride is not deleterious at low levels ∼ 10 gm -3 in the borate solutions. The significant improvement in corrosion control demonstrated for the change from pH7 to pH9.2 borate solution on laboratory sensitised brace samples should ideally be confirmed using complete irradiated AGR fuel elements. (U.K.)

Development of a mobility and fuel strategy for Germany. Preliminary investigation; Entwicklung einer Mobilitaets- und Kraftstoffstrategie fuer Deutschland. Voruntersuchung

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-08-15

Mobility is a key element in our society and often synonymous with traffic. It is desirable to secure a clean and diversified energy supply, to design a more sustainable transport structure and to minimize the burden on people and environment. This requires an updating of the fuel strategy 2004 and its progress toward a comprehensive mobility strategy and fuel strategy. Under this aspect, the contribution under consideration presents a preliminary investigation of the development of a mobility strategy and fuel strategy in Germany. Over the past ten years, the transport sector has reduced its energy consumption only slightly. The targets for the energy reduction now are -10 % up to 2020 and -40 % up to 2050. The transport sector challenges a significant contribution to the reduction of greenhouse gas emissions. In order to advance the necessary energy political as well as climate political changes the Federal Government wants to develop a comprehensive mobility strategy and fuel strategy. For this purpose, the contribution under consideration provides nine concrete recommendations for action for this.

Conversion of actinide solutions for the production of MA bearing fuels for Gen IV fast reactor systems

International Nuclear Information System (INIS)

Fernandez, A.; McGinley, J.; Somers, J.

2008-01-01

The conversion of the solution to solid for fuels containing minor actinides for accelerator driven systems or Gen IV fast reactors cannot be made by conventional ammonia or oxalate precipitation as is the case in today's reprocessing plant. The small particle size and concomitant dust that is produced in subsequent processing steps will not permit use of these processes on industrial scale. Innovation is needed to avoid dust generating powders, and indeed to simplify the processes themselves. Two such processing routes have been developed at the JRC-ITU. The sol gel route has been used to produce fuel containing Am and Np for the SUPERFACT, TRABANT and other irradiation experiments. The infiltration process has also been established and fuels have been produced for the FUTURIX and HELIOS experiments. (authors)

Conversion of actinide solutions for the production of MA bearing fuels for Gen IV fast reactor systems

Energy Technology Data Exchange (ETDEWEB)

Fernandez, A.; McGinley, J.; Somers, J. [European Commission, Joint Research Centre, Institute for Transuranium Elements P.O.Box 2340, Karlsruhe, D-76125 (Germany)

2008-07-01

The conversion of the solution to solid for fuels containing minor actinides for accelerator driven systems or Gen IV fast reactors cannot be made by conventional ammonia or oxalate precipitation as is the case in today's reprocessing plant. The small particle size and concomitant dust that is produced in subsequent processing steps will not permit use of these processes on industrial scale. Innovation is needed to avoid dust generating powders, and indeed to simplify the processes themselves. Two such processing routes have been developed at the JRC-ITU. The sol gel route has been used to produce fuel containing Am and Np for the SUPERFACT, TRABANT and other irradiation experiments. The infiltration process has also been established and fuels have been produced for the FUTURIX and HELIOS experiments. (authors)

Solar-aided air conditioning through sorption. Final report. Phase 2; Solar unterstuetzte Klimatisierung ueber Sorption. Endbericht zur Phase 2

Energy Technology Data Exchange (ETDEWEB)

Laevemann, E; Kessling, W; Peltzer, M

1996-09-24

The present article reports on possibilities of using solar energy for cooling buildings. It contains the following chapters: Current state of research and development; room air conditioning; planning and results of the studies; theory; experimental studies on the sorption dehumidifier; development of exchange surfaces; development of solution distributors; cooling of exchange surfaces; construction of a sorption dehumidifier. (HW) [Deutsch] Die Arbeit berichtet ueber Moeglichkeiten der Anwendung von Solarenergie zur Kuehlung von Gebaeuden. Die Arbeit enthaelt folgende Kapitel: - Stand der Forschung und Entwicklung - Raumklimatisierung - Planung und Ergebnis der Untersuchungen - Theorie - Experimentelle Untersuchungen am Sorptionsentfeuchter - Entwicklung von Austauschflaechen - Entwicklung von Loesungsverteilern - Kuehlung von Austauschflaechen - Konstruktion eines Sorptionsentfeuchters. (HW)

Geologic disposal as optimal solution of managing the spent nuclear fuel and high-level radioactive waste

International Nuclear Information System (INIS)

Ilie, P.; Didita, L.; Ionescu, A.; Deaconu, V.

2002-01-01

To date there exist three alternatives for the concept of geological disposal: 1. storing the high-level waste (HLW) and spent nuclear fuel (SNF) on ground repositories; 2. solutions implying advanced separation processes including partitioning and transmutation (P and T) and eventual disposal in outer space; 3. geological disposal in repositories excavated in rocks. Ground storing seems to be advantageous as it ensures a secure sustainable storing system over many centuries (about 300 years). On the other hand ground storing would be only a postponement in decision making and will be eventually followed by geological disposal. Research in the P and T field is expected to entail a significant reduction of the amount of long-lived radioactive waste although the long term geological disposal will be not eliminated. Having in view the high cost, as well as the diversity of conditions in the countries owning power reactors it appears as a reasonable regional solution of HLW disposal that of sharing a common geological disposal. In Romania legislation concerning of radioactive waste is based on the Law concerning Spent Nuclear Fuel and Radioactive Waste Management in View of Final Disposal. One admits at present that for Romania geological disposal is not yet a stressing issue and hence intermediate ground storing of SNF will allow time for finding a better final solution

Paleo-oil and gas fields in the red sandstone of the North German Basin: Effects of hydrocarbon migration on storage quality development. Fluid flow, diagenesis and storage quality in the red sandstone strata of northern Germany; Palaeo-Oel- und -Gasfelder im Rotliegenden des Norddeutschen Beckens: Wirkung der KW-Migration auf die Speicherqualitaets-Entwicklung. Fluidfluss, Diagenese und Speicherqualitaet im Rotliegend Norddeutschlands

Energy Technology Data Exchange (ETDEWEB)

Solms, M. [SGC, Lehrte (Germany); Gaupp, R. [Jena Univ. (Germany); Littke, R.; Schwarzer, D. [RWTH Aachen (Germany); Schubarth-Engelschall, J.; Trappe, H. [TEEC, Isernhagen (Germany); Krawczyk, C.; Tanner, D.; Oncken, O. [GFZ, Potsdam (Germany)

2003-07-01

This sub-project was aimed at improving the geological concept of the development of storage quality, at the development of a model for monitoring and reconstruction of the structural development and restructuring of reservoirs, and at obtaining information on hydrocarbon origins, migration pathways and filling chronology. Drill core data were combined with 3D seismic data in order to obtain a deeper understanding of the processes involved. [German] Im Rahmen des DGMK-Forschungsprogrammes ''Tight Gas Reservoirs'' (Projekt 593-8) wurden von der Arbeitsgruppe Sedimentologie 43 Bohrungen aus dem Rotliegend Nordwestdeutschlands untersucht. Die vorgestellten Ergebnisse schliessen sich an den Vortrag ''Einfluss von Fazies und Diagenese auf die Speicher-Qualitaets-Entwicklung von Rotliegendsandsteinen NW Deutschlands'' (SOLMS et al., DGMK-Fruehjahrstagung 2002). Ziel dieses Teilprojektes ist die Verbesserung des geologischen Konzeptes zur Entwicklung der Speicherqualitaet, die Entwicklung eines Modells zur Erfassung und Rekonstruktion der strukturellen Entwicklung und Restrukturierung von Lagerstaetten sowie die Klaerung von KW-Herkunftsgebieten, Migrationswegen und Fuellungschronologien. Durch die Verknuepfung der Kerndaten mit 3D seismischen Daten soll eine verbesserte Einschaetzung der Speicherqualitaeten aus dem 3D seismischen Abbild erreicht werden. (orig.)

Simultaneous pollutant removal and electricity generation in denitrifying microbial fuel cell with boric acid-borate buffer solution.

Science.gov (United States)

Chen, Gang; Zhang, Shaohui; Li, Meng; Wei, Yan

2015-01-01

A double-chamber denitrifying microbial fuel cell (MFC), using boric acid-borate buffer solution as an alternative to phosphate buffer solution, was set up to investigate the influence of buffer solution concentration, temperature and external resistance on electricity generation and pollutant removal efficiency. The result revealed that the denitrifying MFC with boric acid-borate buffer solution was successfully started up in 51 days, with a stable cell voltage of 205.1 ± 1.96 mV at an external resistance of 50 Ω. Higher concentration of buffer solution favored nitrogen removal and electricity generation. The maximum power density of 8.27 W/m(3) net cathodic chamber was obtained at a buffer solution concentration of 100 mmol/L. An increase in temperature benefitted electricity generation and nitrogen removal. A suitable temperature for this denitrifying MFC was suggested to be 25 °C. Decreasing the external resistance favored nitrogen removal and organic matter consumption by exoelectrogens.

Dynamic tritium inventory of a NET/ITER fuel cycle with lithium salt solution blanket

International Nuclear Information System (INIS)

Spannagel, G.; Gierszewski, P.

1991-01-01

At the Karlsruhe Nuclear Research Center (KfK) a flexible tool is being developed to simulate the dynamics of tritium inventories. This tool can be applied to any tritium handling system, especially to the fuel cycle components of future nuclear fusion devices. This instrument of simulation will be validated in equipment to be operated at the Karlsruhe Tritium Laboratory. In this study tritium inventories in a NET/ITER type fuel cycle involving a lithium salt solution blanket are investigated. The salt solution blanket serves as an example because it offers technological properties which are attractive in modeling the process; the example does not impair the general validity of the tool. Usually, the operation strategy of complex structures will deteriorate due to failures of the subsystems involved. These failures together with the reduced availability ensuing from them will be simulated. The example of this study is restricted to reduced availabilities of two subsystems, namely the reactor and the tritium recovery system. For these subsystems the influence of statistically varying intervals of operation is considered. Strategies we selected which are representative of expected modes of operation. In the design of a fuel cycle, care will be taken that prescribed availabilities of the subsystems can be achieved; however, the description of reactor operation is a complex task since operation breaks down into several campaigns for which rules have been specified which enable determination of whether a campaign has been successful and can be stopped. Thus, it is difficult to predict the overall behavior prior to a simulation which includes stochastic elements. Using the example mentioned above the capabilities of the tool will be illustrated; besides the presentation of results of inventory simulation, the applicability of these data will be discussed. (orig.)

Oxidizing dissolution of spent MOX47 fuel subjected to water radiolysis: Solution chemistry and surface characterization by Raman spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Jegou, C., E-mail: christophe.jegou@cea.f [Commissariat a l' Energie Atomique (CEA), Marcoule Reasearch Center, B.P. 17171, F-30207 Bagnols-sur-Ceze Cedex (France); Caraballo, R.; De Bonfils, J.; Broudic, V.; Peuget, S. [Commissariat a l' Energie Atomique (CEA), Marcoule Reasearch Center, B.P. 17171, F-30207 Bagnols-sur-Ceze Cedex (France); Vercouter, T. [Commissariat a l' Energie Atomique (CEA), Saclay Reasearch Center, B.P. 11, F-91191 Gif-sur-Yvette Cedex (France); Roudil, D. [Commissariat a l' Energie Atomique (CEA), Marcoule Reasearch Center, B.P. 17171, F-30207 Bagnols-sur-Ceze Cedex (France)

2010-04-01

The mechanisms of oxidizing dissolution of spent MOX fuel (MIMAS TU2 (registered) ) subjected to water radiolysis were investigated experimentally by leaching spent MOX47 fuel samples in pure water at 25 deg. C under different oxidizing conditions (with and without external gamma irradiation); the leached surfaces were characterized by Raman spectroscopy. The highly oxidizing conditions resulting from external gamma irradiation significantly increased the concentration of plutonium (Pu(V)) and uranium (U(VI)) compared with a benchmark experiment (without external irradiation). The oxidation behavior of the plutonium-enriched aggregates differed significantly from that of the UO{sub 2} matrix after several months of leaching in water under gamma irradiation. The plutonium in the aggregates appears to limit fuel oxidation. The only secondary phases formed and identified to date by Raman spectroscopy are uranium peroxides that generally precipitate on the surface of the UO{sub 2} grains. Concerning the behavior of plutonium, solution analysis results appear to be compatible with a conventional explanation based on an equilibrium with a Pu(OH){sub 4(am)} phase. The fission product release - considered as a general indicator of matrix alteration - from MOX47 fuel also increases under external gamma irradiation and a change in the leaching mode is observed. Diffusive leaching was clearly identified, coinciding with the rapid onset of steady-state actinide concentrations in the bulk solution.

Fuel mix electricity 2020, inventory, problems and solutions

International Nuclear Information System (INIS)

Seebregts, A.J.; Snoep, H.J.M.; Van Deurzen, J.; Lensink, S.M.; Van der Welle, A.J.; Wetzels, W.

2010-04-01

ECN made an inventory of the fuel mix of the electricity generation in the Netherlands for the year 2020. The inventory is derived from the updated Reference Projections that are based on the Global Economy scenario. This scenario has a relatively high growth of the domestic electricity demand (156 TWh in 2020 compared to about 118 TWh in 2008). Besides the factual inventory, ECN made a quickscan of potential problems associated with high penetration of electricity from wind energy, up to 12,000 MW in 2020. The conclusion is that the so-called 'offpeak hours issue' (in Dutch: 'het daluren issue') is a real potential problem under such scenario assumptions. In case of full wind availability, the total generating capacity consisting of must-run capacity and typical base load power plants with low variable cost of production (nuclear and coal) may exceed the electricity demand (domestic plus net export) in part of these off-peak situations, e.g. during nighttime. The must-run capacity consists, among others, of part of the decentralised CHP installations and waste incinerators. Potential solutions to this 'off-peak hours issue' are: (1) Flexibility in electricity demand ('demand response'); (2) Additional interconnection with neighbouring countries and appropriate market design rules; (3) Storage of electricity; (4) Flexibility of conventional (fossil) supply; (5) Flexibility of the intermittent renewable generation itself; (6) Intelligent grids ('Smart Grids'). Additional detailed analyses and research are needed to address the magnitude of the problem and to analyse the contribution of the various solutions. Such an analysis can provide an indication of an optimal and feasible combination of the solutions identified. Relevant issues are: (a) How often, with which magnitude and under which circumstances will the problem occur?; (b) What will be the effect on the curtailing of wind energy, and is curtailing plausible given current market rules and renewable energy

Training Course of Experimental Chemistry in the Nuclear Fuel Cycle: Solid State and Solution Chemistry

Energy Technology Data Exchange (ETDEWEB)

Lee, Ju hyeong; Park, Kwangheon; Kim, Tae hoon; Park, Hyoung gyu; Kim, Jisu [Kyunghee University, Yongin (Korea, Republic of); Song, Hyuk jin [Dongguk University, Gyeongju (Korea, Republic of); Lee, Chan ki; Kang, Do kyu; Jeong, Hyeon jun [UNIST, Ulsan (Korea, Republic of)

2016-10-15

In this experimental study program in Tohoku University, basic experiments were done by the participants. First one is the hydrogen reduction experiment of the mixture of UO{sub 2} and ZrO{sub 2}. Second one is to observe microscopic structure of solid solution of UO{sub 2} and ZrO{sub 2} using SEM/EDX and XRD system, simulated fuel debris. Third one is milking process of {sup 239}Np from {sup 243}Am by solvent extraction using Tri-n-Octylamine (TOA). Last one is solvent extraction in PUREX by the simulated mixed aqueous solution of U, {sup 85}Sr and {sup 239}Np which is represented minor actinide elements included in the spent nuclear fuel. Uranium is separated from aqueous phase to organic phase during solvent extraction procedure using TBP and dodecane. Also, neptunium can be extracted to organic phase as nitric acid concentration change. The extraction behavior of neptunium is different by oxidation state in aqueous phase. The behavior of neptunium is represented as a combined form of these oxidation states in experiment. Therefore, because the oxidation states of neptunium can be controlled by controlling the concentration of nitric acid, the extractability of neptunium can be controlled.

Mechatronics in the car: success through efficient methodological development; Mechatronik im Kraftfahrzeug: Erfolg durch effiziente Entwicklungsmethodik

Energy Technology Data Exchange (ETDEWEB)

Dieterle, W.; Dilger, E. [Bosch (R.) GmbH, Gerlingen (Germany). Zentralbereich Forschung und Vorausentwicklung; Buerger, K.G. [Bosch (R.) GmbH (Germany)

2001-04-01

The ever increasing requirements with respect to fuel consumption, emissions as well as safety and comfort necessitate ever increasing complex functionalities in the car. They are realized, as a rule, by a combination of mechanics, hydraulics, electrics/electronics and, more and more, software. In the past, the development of the various electric/electronic, mechanical or hydraulic components tended to happen at separate levels, nowadays the focus is more on a comprehensive approach to the overall system. In this context, the integrated development of 'mechatronic' components, including the respective software, leads to a targeted solution. (orig.) [German] Staendig steigende Anforderungen hinsichtlich Kraftstoffverbrauch, Emissionen sowie Sicherheit und Komfort bedingen immer komplexere Funktionalitaeten im Kraftfahrzeug. Sie werden in der Regel durch eine Kombination von Mechanik, Hydraulik, Elektrik/Elektronik und zunehmend auch Software realisiert. Nachdem in der Vergangenheit die Entwicklung meist noch auf getrennten Ebenen verlief, steht heute ein uebergreifender, das Gesamtsystem umfassender Ansatz im Vordergrund. Dieser Beitrag der Robert Bosch GmbH berichtet ueber aktuelle Mechatronik-Entwicklungen. Dabei sorgt die integrierte Entwicklung der 'mechatronischen' Komponenten unter Einbezug der zugehoerigen Software fuer eine zielgerichtete Loesung. (orig.)

Novel materials for fuel cells operating on liquid fuels

Directory of Open Access Journals (Sweden)

César A. C. Sequeira

2017-05-01

Full Text Available Towards commercialization of fuel cell products in the coming years, the fuel cell systems are being redefined by means of lowering costs of basic elements, such as electrolytes and membranes, electrode and catalyst materials, as well as of increasing power density and long-term stability. Among different kinds of fuel cells, low-temperature polymer electrolyte membrane fuel cells (PEMFCs are of major importance, but their problems related to hydrogen storage and distribution are forcing the development of liquid fuels such as methanol, ethanol, sodium borohydride and ammonia. In respect to hydrogen, methanol is cheaper, easier to handle, transport and store, and has a high theoretical energy density. The second most studied liquid fuel is ethanol, but it is necessary to note that the highest theoretically energy conversion efficiency should be reached in a cell operating on sodium borohydride alkaline solution. It is clear that proper solutions need to be developed, by using novel catalysts, namely nanostructured single phase and composite materials, oxidant enrichment technologies and catalytic activity increasing. In this paper these main directions will be considered.

Selection of dissolution process for spent fuels and preparation of corrosion test solution simulated to dissolver (contract research)

International Nuclear Information System (INIS)

Motooka, Takafumi; Terakado, Shogo; Koya, Toshio; Hamada, Shozo; Kiuchi, Kiyoshi

2001-03-01

In order to evaluate the reliability of reprocessing equipment materials used in the Rokkasho Reprocessing Plant, we have proceeded a mock-up test and laboratory tests for getting corrosion parameters. In a dissolver made of zirconium, the simulation of test solutions to the practical solution which includes the high concentration of radioactive elements such as FP and TRU is one of the important issues with respect to the life prediction. On this experiment, the dissolution process of spent fuels and the preparation of test solution for evaluating the corrosion resistance of dissolver materials were selected. These processes were tested in the No.3 cell of WASTEF. The test solution for corrosion tests was prepared by adjusting the uranium and nitric acid concentrations. (author)

Criticality safety evaluation report for MKIA fuel pertaining to consolidating fuel storage

International Nuclear Information System (INIS)

Schwinkendorf, K.N.

1994-10-01

Irradiated fuel criticality calculations are performed for MKIA fuel, 1.25 wt% 235 U, and 1.15 wt% 235 U fuel pieces and solutions. Comparisons are made between WIMS and MCNP. WIMS and MCNP calculations are documented

Interactions of hydrazine, ferrous sulfamate, sodium nitrite, and nitric acid in nuclear fuel processing solutions

International Nuclear Information System (INIS)

Gray, L.W.

1977-03-01

Hydrazine and ferrous sulfamate are used as reductants in a variety of nuclear fuel processing solutions. An oxidant, normally sodium nitrite, must frequently be added to these nitric acid solutions before additional processing can proceed. The interactions of these four chemicals have been studied under a wide variety of conditions using a 2/sup p/ factorial experimental design to determine relative reaction rates for desired reactions and side reactions. Evidence for a hydrazine-stabilized, sulfamic acid--nitrous acid intermediate was obtained; this intermediate can hydrolyze to ammonia or decompose to nitrogen. The oxidation of Fe 2+ by NO 2 - was shown to proceed at about the same rate as the scavenging of NO 2 - by sulfamic acid. Various side reactions are discussed

Method and Result of Experiment for Support of Technical Solutions in the Field of Perfection of a Nuclear Fuel Cycle for Future PWR Reactors

International Nuclear Information System (INIS)

Ostrovskiy, V.; Kudryavtsev, E.; Tutnov, I.

2011-01-01

The paper presents the basics of approach of planning and carrying out of experiments to validate safety PWR reactors of the future when accepting technical solutions concerning using of improved fuel rods in fuel assembly. Basic principles and criteria used for the validation of technical solutions and developments in improving of nuclear fuel cycle of PWR reactors of the future are presented from the point of safety of future operation of modified fuel rods. We explore the questions of safety operation of PWR reactors with fuel assemblies, containing fuel rods with different length of fuel. The paper discusses the ways of solving of important tasks of critical facility experiments conducting for verification of new technical solutions in the sphere of PWR nuclear fuel cycle improvement on the base of international standards ISO 2000:9000 and functional safety recommendations of IEC (International Electromechanical Commission). New Federal laws of Russian Federation define the main principle for demands to NPP and any supplier of nuclear techniques. The principle is 'quantity indicators of risk should not exceed comprehensible social size of the established indicators of safety for any moment of operation of NPP'. On the other hand the second principle should be applied to extraction of the greatest benefit from operation of the equipment, systems or the NPP as whole: 'The long operation and full commercial use of resource and service properties of the equipment, systems and the NPP as a whole'. Realization of this principle assumes development and introduction of new technical solutions for a validation of guarantees of safety of the future operation of NPP or it separate components. Solving the practical problems of a validation of safety use of fuel rods with the increased length of a fuel column in fuel assembly in nuclear reactors of the future, we should choose new strategies and programs of verification experiments on the base of the analysis of guarantees

Features of the Numerical Solution of Thermal Destruction Fuel Pins Problems in the Fast Reactor

Science.gov (United States)

Usov, E. V.; Butov, A. A.; Klimonov, I. A.; Chuhno, V. I.; Nikolaenko, A. V.; Zhdanov, V. S.; Pribaturin, N. A.; Strizhov, V. F.

2017-11-01

In this paper the description of the basic equations which can be used for calculation of melting of fuel and cladding of the fast reactor, moving of the melt on a fuel pin surface and its solidification is presented. The special attention is given speed of calculation algorithms and fidelity of the phenomena which are observed at a stage of severe accidents in fast reactors. For check of working capacity of initial models, numerical calculations of Stefan-type problems on front movement of melting/solidification in cylindrical geometry are presented. Comparison with the solutions received by known analytical methods is executed. For validation of the numerical realization of calculation algorithms the analysis is carried out and experiments in which melting of the model fuel pins of fast reactors was studied are chosen. On the basis of the chosen experiments calculation schemes taking into account initial and boundary conditions are prepared and modeling is performed. Modeling results are shown in the present paper. Estimation of calculation error of the basic physical parameters is done by results of the modeling and conclusions are drawn on a correctness of algorithms operation.

PLUTONIUM METALLIC FUELS FOR FAST REACTORS

Energy Technology Data Exchange (ETDEWEB)

STAN, MARIUS [Los Alamos National Laboratory; HECKER, SIEGFRIED S. [Los Alamos National Laboratory

2007-02-07

Early interest in metallic plutonium fuels for fast reactors led to much research on plutonium alloy systems including binary solid solutions with the addition of aluminum, gallium, or zirconium and low-melting eutectic alloys with iron and nickel or cobalt. There was also interest in ternaries of these elements with plutonium and cerium. The solid solution and eutectic alloys have most unusual properties, including negative thermal expansion in some solid-solution alloys and the highest viscosity known for liquid metals in the Pu-Fe system. Although metallic fuels have many potential advantages over ceramic fuels, the early attempts were unsuccessful because these fuels suffered from high swelling rates during burn up and high smearing densities. The liquid metal fuels experienced excessive corrosion. Subsequent work on higher-melting U-PuZr metallic fuels was much more promising. In light of the recent rebirth of interest in fast reactors, we review some of the key properties of the early fuels and discuss the challenges presented by the ternary alloys.

A comparison of sodium borohydride as a fuel for proton exchange membrane fuel cells and for direct borohydride fuel cells

Science.gov (United States)

Wee, Jung-Ho

Two types of fuel cell systems using NaBH 4 aqueous solution as a fuel are possible: the hydrogen/air proton exchange membrane fuel cell (PEMFC) which uses onsite H 2 generated via the NaBH 4 hydrolysis reaction (B-PEMFC) at the anode and the direct borohydride fuel cell (DBFC) system which directly uses NaBH 4 aqueous solution at the anode and air at the cathode. Recently, research on these two types of fuel cells has begun to attract interest due to the various benefits of this liquid fuel for fuel cell systems for portable applications. It might therefore be relevant at this stage to evaluate the relative competitiveness of the two fuel cells. Considering their current technologies and the high price of NaBH 4, this paper evaluated and analyzed the factors influencing the relative favorability of each type of fuel cell. Their relative competitiveness was strongly dependent on the extent of the NaBH 4 crossover. When considering the crossover in DBFC systems, the total costs of the B-PEMFC system were the most competitive among the fuel cell systems. On the other hand, if the crossover problem were to be completely overcome, the total cost of the DBFC system generating six electrons (6e-DBFC) would be very similar to that of the B-PEMFC system. The DBFC system generating eight electrons (8e-DBFC) became even more competitive if the problem of crossover can be overcome. However, in this case, the volume of NaBH 4 aqueous solution consumed by the DBFC was larger than that consumed by the B-PEMFC.

Synthesis of Diopside by Solution Combustion Process Using Glycine Fuel

Science.gov (United States)

Sherikar, Baburao N.; Umarji, A. M.

Nano ceramic Diopside (CaMgSi2O6) powders are synthesized by Solution Combustion Process(SCS) using Calcium nitrate, Magnesium nitrate as oxidizer and glycine as fuel, fumed silica as silica source. Ammonium nitrate (AN) is used as extra oxidizer. Effect of AN on Diopside phase formation is investigated. The adiabatic flame temperatures are calculated theoretically for varying amount of AN according to thermodynamic concept and correlated with the observed flame temperatures. A “Multi channel thermocouple setup connected to computer interfaced Keithley multi voltmeter 2700” is used to monitor the thermal events during the process. An interpretation based on maximum combustion temperature and the amount of gases produced during reaction for various AN compositions has been proposed for the nature of combustion and its correlation with the characteristics of as synthesized powder. These powders are characterized by XRD, SEM showing that the powders are composed of polycrystalline oxides with crystallite size of 58nm to 74nm.

Soziologische Wissenskulturen zwischen individualisierter Inspiration und prozeduraler Legitimation. Zur Entwicklung qualitativer und interpretativer Sozialforschung in der deutschen und französischen Soziologie seit den 1960er Jahren

Directory of Open Access Journals (Sweden)

Reiner Keller

2016-01-01

Full Text Available Wie wissen Soziologinnen und Soziologen, was sie wissen? Trotz der Internationalisierung der Soziologie bestehen nach wie vor starke sprachräumliche Unterschiede in der soziologischen Wissensproduktion, in eingesetzten Theorien, Methoden und Fragestellungen. Der nachfolgende Beitrag erläutert die Entwicklung und Ausprägung der Unterschiedlichkeit soziologischer Wissenskulturen im Hinblick auf den Einsatz qualitativer bzw. interpretativer Ansätze seit den 1960er Jahren in Deutschland und Frankreich. Er stützt sich auf ein von uns 2012-2014 geleitetes Forschungsprojekt und dessen empirische Grundlagen: Dokumentenanalysen und Interviews. Wissenskulturen werden als die Arten und Weisen der Produktion und Legitimation von (hier: soziologischem Wissen verstanden. Diesbezüglich lässt sich von der Erkenntnisproduktion als dem zentralen Handlungsproblem soziologischen Forschens sprechen. Während für die französischsprachige Soziologie diagnostisch von einer Lösung dieses Erkenntnisproblems durch die den Forschenden zugeschriebenen Kompetenzen und Inspirationen ausgegangen werden kann, schiebt sich im deutschsprachigen Raume eine prozedurale Legitimation durch Verfahren in den Vordergrund. Der Beitrag rekonstruiert exemplarisch die Ausgangssituation dieser Entwicklungen um die Wende zu den 1960er Jahren und bettet sie in die weitere Entfaltung der jeweiligen Soziologien ein. Er will damit zur gegenwärtigen Entwicklung einer reflexiven Soziologie beitragen. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1601145

Development of a real-time fuel cell stack modelling solution with integrated test rig interface for the generic fuel cell modelling environment (GenFC) software

Energy Technology Data Exchange (ETDEWEB)

Fraser, S.D.; Monsberger, M.; Hacker, V. [Graz Univ. of Technology, Graz (Austria). Christian Doppler Laboratory for Fuel Cell Systems; Gubner, A.; Reimer, U. [Forschungszentrum Julich, Julich (Germany)

2007-07-01

Since the late 1980s, numerous FC models have been developed by scientists and engineers worldwide to design, control and optimize fuel cells (FCs) and fuel cell (FC) power systems. However, state-of-the-art FC models have only a small range of applications within the versatile field of FC modelling. As fuel cell technology approaches commercialization, the scientific community is faced with the challenge of providing robust fuel cell models that are compatible with established processes in industrial product development. One such process, known as Hardware in the Loop (HiL), requires real-time modelling capability. HiL is used for developing and testing hardware components by adding the complexity of the related dynamic systems with mathematical representations. Sensors and actuators are used to interface simulated and actual hardware components. As such, real-time fuel cell models are among the key elements in the development of the Generic Fuel Cell Modelling Environment (GenFC) software. Six European partners are developing GenFC under the support of the Sixth European Framework Programme for Research and Technological Development (FP6). GenFC is meant to increase the use of fuel cell modelling for systems design and to enable cost- and time-efficient virtual experiments for optimizing operating parameters. This paper presented an overview of the GenFC software and the GenFC HiL functionality. It was concluded that GenFC is going to be an extendable software tool providing FC modelling techniques and solutions to a wide range of different FC modelling applications. By combining the flexibility of the GenFC software with this HiL-specific functionality, GenFC is going to promote the use of FC model-based HiL technology in FC system development. 9 figs.

Der Weg zum Java-Profi Konzepte und Techniken für die professionelle Java-Entwicklung

CERN Document Server

Inden, Michael

2015-01-01

Sie haben bereits Einiges an Erfahrung mit Java und möchten Ihre Entwicklungstätigkeit nun professionalisieren? Oder sind Sie schon auf dem Weg zum Profi, benötigen aber ein Nachschlagewerk, das Ihnen die wichtigen Themen aus der Java-Welt kompakt und kompetent vermittelt? Dieses Buch bietet eine umfassende Einführung in die professionelle Entwicklung und vermittelt Ihnen das notwendige Wissen, um stabile und erweiterbare Softwaresysteme auf Java-SE-Basis zu bauen. Praxisnahe Beispiele helfen dabei, das Gelernte rasch umzusetzen. Neben der Praxis wird viel Wert auf das Verständnis zugrunde liegender Konzepte gelegt. Dabei kommen dem Autor Michael Inden seine umfangreichen Schulungs- und Entwicklererfahrungen zugute - und Ihnen als Leser damit ebenso. Diese Neuauflage wurde durchgehend überarbeitet, aktualisiert und erweitert. Natürlich darf das aktuelle Java 8 nicht fehlen. Verschiedene Kapitel sind Java 8 und seinen Neuerungen gewidmet. Dort wird ein fundierter Einstieg in die umfangreichen Erweit...

Development of renewable energy sources in Germany 2014. Charts and figures based on statistical data from the working group on renewable energy-statistics (AGEE-Stat); Entwicklung der erneuerbaren Energien in Deutschland im Jahr 2014. Grafiken und Diagramme unter Verwendung aktueller Daten der Arbeitsgruppe Erneuerbare Energien-Statistik (AGEE-Stat)

Energy Technology Data Exchange (ETDEWEB)

Nieder, Thomas; Bickel, Peter; Musiol, Frank (comps.) [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg (ZSW), Stuttgart (Germany)

2015-12-15

The more than 30 diagrams and graphs describe the development of the importance of renewable energy in Germany by the year 2014. Also, discusses the development of avoided greenhouse emissions through renewable energies, as well as the investments and their economic impulses for Germany. Some technical terms are conclusively explained in a glossary. [German] Die mehr als 30 Diagramme und Graphiken beschreiben die Entwicklung der Bedeutung der erneuerbaren Energien fuer Deutschland bis zum Jahr 2014. Auch wird auf die Entwicklung der vermiedenen Treibhaus-Emissionen durch erneuerbare Energien, sowie die Investitionen und deren wirtschaftlichen Impulse fuer Deutschland eingegangen. Einige Fachbegriffe werden abschliessend in einem Glossar erlaeutert.

Nothing stays ever the same. Stationary fuel cells, the revolution in domestic and industrial power supply; Nichts bleibt, wie es ist.... Revolution der Energieversorgung in der Haustechnik und Industrie mit stationaeren Brennstoffzellen

Energy Technology Data Exchange (ETDEWEB)

Anon.

2001-02-01

Helmut Kaiser Unternehmensberatung (HKU), an organisation that claims to be a leading consultant in the fields of environmental engineering, energy engineering, health and life science, investigated the current trends in stationary fuel cell applications world-wide. The study covers market and technology forecasts and an analysis of the competitive standing of suppliers world-wide. [German] Die Helmut Kaiser Unternehmensberatung (HKU), nach eigenen Angaben weltweit eines der fuehrenden Forschungs- und Beratungsunternehmen in der Umwelt-, Energietechnik sowie Gesundheit (Life Science), untersuchte in einer neuen Studie die Entwicklung der Brennstoffzellen in der stationaeren Anwendung weltweit. Die Studie umfasst Markt- und Technologieprognosen sowie eine Wettbewerbsanalyse der Anbieter weltweit. (orig.)

Plutonium fuel program

International Nuclear Information System (INIS)

1979-09-01

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.)

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, JCH FUEL SOLUTIONS, INC., JCH ENVIRO AUTOMATED FUEL CLEANING AND MAINTENANCE SYSTEM

Science.gov (United States)

The verification testing was conducted at the Cl facility in North Las Vegas, NV, on July 17 and 18, 2001. During this period, engine emissions, fuel consumption, and fuel quality were evaluated with contaminated and cleaned fuel.To facilitate this verification, JCH repre...

Effects of Fuel to Synthesis of CaTiO3 by Solution Combustion Synthesis for High-Level Nuclear Waste Ceramics.

Science.gov (United States)

Jung, Choong-Hwan; Kim, Yeon-Ku; Han, Young-Min; Lee, Sang-Jin

2016-02-01

A solution combustion process for the synthesis of perovskite (CaTiO3) powders is described. Perovskite is one of the crystalline host matrics for the disposal of high-level radioactive wastes (HLW) because it immobilizes Sr and Lns elements by forming solid solutions. Solution combustion synthesis, which is a self-sustaining oxi-reduction reaction between nitrate and organic fuel, the exothermic reaction, and the heat evolved convert the precursors into their corresponding oxide products above 1100 degrees C in air. To investigate the effects of amino acid on the combustion reaction, various types of fuels were used; a glycine, amine and carboxylic ligand mixture. Sr, La and Gd-nitrate with equivalent amounts of up to 20% of CaTiO3 were mixed with Ca and Ti nitrate and amino acid. X-ray diffraction analysis, SEM and TEM were conducted to confirm the formed phases and morphologies. While powders with an uncontrolled shape are obtained through a general oxide-route process, Ca(Sr, Lns)TiO3 powders with micro-sized soft agglomerates consisting of nano-sized primary particles can be prepared using this method.

Wildnisbildung als Möglichkeit zur Professionalisierung zukünftiger Geographielehrer/innen – ein neuer Ansatz zur Bildung für nachhaltige Entwicklung?. GW-Unterricht|GW-Unterricht 142/143|

OpenAIRE

Lindau, Anne-Kathrin; Hottenroth, Daniela; Lindner, Martin

2016-01-01

Der in den deutschen Nationalparken seit mehreren Jahren thematisierte und praktizierte Ansatz der Wildnisbildung stellt möglicherweise einen neuen Zugang zur Bildung für nachhaltige Entwicklung (BNE) in der universitären Lehrer/innenbildung im Fach Geographie dar. Am Beispiel des DBU-geförderten Projektes „Wildnis macht stark“ wird eine Konzeption für die Umsetzung von Wildnisbildung im Rahmen des Geographie-Lehramtsstudiums vorgestellt und mit ersten Forschungsergebnissen zur Wirksamkeit in...

Development of new layer systems for sliding bearings under high mechanical and tribological stress. Final report; Entwicklung neuer Schichtsysteme fuer den Einsatz bei mechanisch-tribologisch hochbeanspruchten Gleitlagern. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Mathias, M.; Herrmann, B.

1995-12-31

The report describes the sputtering technique as a coating method for sliding bearings of high-speed diesel engines. The project aimed at the development of a heavy-duty, wear-resistant sputtered layer on a copper-lead basis for sliding bearings. (HW) [Deutsch] Es wird berichtet ueber die Einfuehrung der Sputtertechnik als Beschichtungsverfahren fuer Gleitlager fuer schnell laufende Dieselmotoren. Ziel des Projektes war die Entwicklung einer hochbelastbaren, verschleissfesten Gleitlager-Sputterschicht auf Kupfer-Blei-Basis. (HW)

Agro-fuels and climate. Why is it not a good solution?

International Nuclear Information System (INIS)

2015-10-01

This publication explains why agro-fuels raise various problems: deforestation due to a change of land use, impact on climate due to deforestation and higher CO 2 emission by colza-based fuel than by conventional diesel fuel, food safety due to the evolution of land uses which result in higher food prices and land grabbing. It also outlines that agro-fuels are a burden for public finances. Possibilities offered by agro-fuels of third generation are evoked

Approximate solutions of pulse transport in turbulent flow in narrow fuel element bundle geometries, using the FE method

International Nuclear Information System (INIS)

Kaiser, H.G.

1985-01-01

The author is concerned with the flow conditions in case of narrow fuel element grids of pressurised-water reactors. Starting from the mathematical formulation of the flow processes for incompressible, isothermal flows, models of the turbulence characteristics are being developed. Besides turbulence models, and network structure the finite element method is treated as numeric solution process. Finally the results are summarized and discussed. (HAG) [de

Domestic fuel question and the charcoal solution

Energy Technology Data Exchange (ETDEWEB)

Krishna Rao, E G

1981-06-01

Domestic fuel for cooking forms one of the basic needs of human society. In India, the pressure of this need has exceeded the regeneration potential of the growing forests which supply a large proportion of this basic need. The pressure can be greatly relieved by converting wood to charcoal before it reaches the consumer. The present paper examines this aspect and reviews the modern methods of charcoal production on fuelwood resources. Besides being a choice domestic fuel, charcoal is a valuable raw material in various industries. Charcoal making industry can be established as a rural based industry (as part of community forestry projects) and would generate much needed cash income at grassroot level. The strategy would be important in dealing with the problem of chronic poverty at this level. (Refs. 5).

Clarification of dissolved irradiated light-water-reactor fuel

International Nuclear Information System (INIS)

Rodrigues, G.C.

1983-02-01

Bench-scale studies with actual dissolved irradiated light water reactor (LWR) fuels showed that continuous centrifugation is a practical clarification method for reprocessing. Dissolved irradiated LWR fuel was satisfactorily clarified in a bench-scale, continuous-flow bowl centrifuge. The solids separated were successfully reslurried in water. When the reslurried solids were mixed with clarified centrate, the resulting suspension behaved similar to the original dissolver solution during centrifugation. Settling rates for solids in actual irradiated fuel solutions were measured in a bottle centrifuge. The results indicate that dissolver solutions may be clarified under conditions achievable by available plant-scale centrifuge technology. The effective particle diameter of residual solids was calculated to be 0.064 microns for Oconee-1 fuel and 0.138 microns for Dresden-1 fuel. Filtration was shown unsuitable for clarification of LWR fuel solutions. Conventional filtration with filter aid would unacceptably complicate remote canyon operation and maintenance, might introduce dissolved silica from filter aids, and might irreversibly plug the filter with dissolver solids. Inertial filtration exhibited irreversible pluggage with nonradioactive stand-in suspensions under all conditions tested

Isotope dilution alpha spectrometry for the determination of plutonium concentration in irradiated fuel dissolver solution : IDAS and R-IDAS

International Nuclear Information System (INIS)

Ramaniah, M.V.; Jain, H.C.; Aggarwal, S.K.; Chitambar, S.A.; Kavimandan, V.D.; Almaula, A.I.; Shah, P.M.; Parab, A.R.; Sant, V.L.

1980-01-01

The report presents a new technique, Isotope Dilution Alpha Spectrometry (IDAS) and Reverse Isotope Dilution Alpha Spectrometry (R-IDAS) for determining the concentration of plutonium in the irradiated fuel dissolver solution. The method exploits sup(238)Pu in IDAS and sup(239)Pu in R-IDAS as a spike and provides an alternative method to Isotope Dilution Mass Spectrometry (IDMS) which requires enriched sup(242)Pu as a spike. Depending upon the burn-up of the fuel, sup(238)Pu or sup(239)Pu is used as a spike to change the sup(238)Pu/(sup(239)Pu+sup(240)Pu)α activity ratio in the sample by a factor of 10. This change is determined by α-spectrometry on electrodeposited sources using a solid state silicon surface barrier detector coupled to a multichannel analyser. The validity of a simple method based on the geometric progression (G.P.) decrease for the far tail of the spectrum to correct for the tail contribution of sup(238)Pu peak (5.50 MeV) to the low energy sup(239)Pu + sup(240)Pu peak (5.17 MeV) is established. Results for the plutonium concentration on different irradiated fuel dissolver solutions with burn-uo ranging from J,000 to 100,000 MWD/TU are presented and compared with those obtained by IDMS. The values obtained by IDAS or R-IDAS and IDMS agree within 0.5%. (auth.)

Fuel management and economics

Energy Technology Data Exchange (ETDEWEB)

Vendryes, G

1972-11-01

From international conference on nuclear solutions to world energy problems; Washington, District of Columbia, USA (12 Nov The low cost of the fuel cycle is the most attractive feature of the fast neutron breeder reactor. In order to achieve it a good fuel management is essential, with well balanced fixed investment and renewal fuel costs. In addition the designer can optimize the power station as a whole (fuel cycle and thermal characteristics). (auth)

Outline of a fuel treatment facility in NUCEF

International Nuclear Information System (INIS)

Sugikawa, Susumu; Umeda, Miki; Kokusen, Junya

1997-03-01

This report presents outline of the nuclear fuel treatment facility for the purpose of preparing solution fuel used in Static Experiment Critical Facility (STACY) and Transient Experiment Critical Facility (TRACY) in Nuclear Fuel Cycle Safety Engineering Research Facility (NUCEF), including descriptions of process conditions and dimensions of major process equipments on dissolution system of oxide fuel, chemical adjustment system, purification system, acid recovery system, solution fuel storage system, and descriptions of safety design philosophy such as safety considerations of criticality, solvent fire, explosion of hydrogen and red-oil and so on. (author)

Modeling of the anode side of a direct methanol fuel cell with analytical solutions

International Nuclear Information System (INIS)

Mosquera, Martin A.; Lizcano-Valbuena, William H.

2009-01-01

In this work, analytical solutions were derived (for any methanol oxidation reaction order) for the profiles of methanol concentration and proton current density, by assuming diffusion mass transport mechanism, Tafel kinetics, and fast proton transport in the anodic catalyst layer of a direct methanol fuel cell. An expression for the Thiele modulus that allows to express the anodic overpotential as a function of the cell current and kinetic and mass transfer parameters was obtained. For high cell current densities, it was found that the Thiele modulus (φ 2 ) varies quadratically with cell current density; yielding a simple correlation between anodic overpotential and cell current density. Analytical solutions were derived for the profiles of both local methanol concentration in the catalyst layer and local anodic current density in the catalyst layer. Under the assumptions of the model presented here, in general, the local methanol concentration in the catalyst layer cannot be expressed as an explicit function of the position in the layer. In spite of this, the equations presented here for the anodic overpotential allow the derivation of new semi-empirical equations

From waste to traffic fuel (W-fuel)

Energy Technology Data Exchange (ETDEWEB)

Kask, Ue.; Andrijevskaja, J.; Kask, L. [and others

2012-11-01

The EU directive on the promotion of the use of energy from renewable sources (Directive 2009/28/EC) sets a mandatory minimum target for the use of fuels produced using renewable energy sources of 10% of total petrol and diesel consumption in the transport sector by the year 2020. In addition, it states that production of renewable fuels should be consistent with sustainable development and must not endanger biodiversity. In the INTERREG IVA Southern Finland - Estonia Sub-programme, efforts towards finding solutions to the tasks set by the EU were undertaken in co-operation with Finnish and Estonian researchers. The purpose of the 'From Waste to Traffic Fuel' (W-Fuel) project was to promote the sustainable production and use of biogas using locally-sourced biodegradable waste materials from the food and beverage industry and the agricultural and municipal sectors. The ultimate aim of the project was to upgrade the biogas (produced based on anaerobic digestion of biodegradable wastes, sludge, manure, slurry and energy crops) to biomethane with a methane content similar to natural gas, to be further used as transport fuel with the aim of reducing traffic-borne emissions, in particular CO{sub 2}. The project combined waste, energy and traffic solutions in order to decrease emissions, costs and the use of materials. Six case areas in southern Finland and northern Estonia were selected. The two case areas in Estonia were the counties of Harju and Laeaene-Viru in northern Estonia. The project aimed to promote waste and sludge prevention and to commence biogas production and its subsequent upgrading to biomethane for use as a renewable fuel. The project promoted regional businesses and employment in waste treatment and 'green energy' production. On basis of the gathered data, the biogas potentials and prerequisites of each case county were analysed. Furthermore, the environmental, economic and other regional effects of the different options were

Relation of fuel rod service parameters and design requirements to produced fuel rod and their components

International Nuclear Information System (INIS)

Bibilashvili, Yu.K.

1999-01-01

Based on the presented material it is possible to state that there is a very close link between the fuel operational parameters and the requirements for its design and production process. The required performance and life-time of a fuel rod can be only assured by the correctly selected design and process solutions. The economical aspect of this problem is significantly depend on the commercial feasibility of a particular selected solution with the provision of an automated and comparative by inexpensive production of a fuel rod and its components. The operational conditions are also important for the life time of the fuel rods. If there are no special measures for the mitigation of the certain operation conditions the leakage of fuel elements can take place before the planned time. (authors)

Quivers For Special Fuel Rods-Disposal Of Special Fuel Rods In CASTOR V Casks

International Nuclear Information System (INIS)

Bannani, Amin; Cebula, Wojciech; Buchmuller, Olga; Huggenberg, Roland; Helmut Kuhl

2015-01-01

While GNS casks of the CASTOR family are a suitable means to transfer fuel assemblies (FA) from the NPP to an interim dry storage site, Germanys phase-out of nuclear energy has triggered the demand for an additional solution to dispose of special fuel rods (SFR), normally remaining in the fuel pond until the final shutdown of the NPP. SFR are fuel rods that had to be removed from fuel assemblies mainly due to their special condition, e. g. damages in the cladding of the fuel rods which may have occurred during reactor operations. SFR are usually stored in the spent fuel pond after they are removed from the FA. The quiver for special fuel rods features a robust yet simple design, with a high mechanical stability, a reliable leak-tightness and large safety margins for future requirements on safety analysis. The quiver for special fuel rods can be easily adapted to a large variety of different damaged fuel rods and tailored to the specific need of the customer. The quiver for special fuel rods is adaptable e.g. in length and diameter for use in other types of transport and storage casks and is applicable in other countries as well. The overall concept presented here is a first of its kind solution for the disposal of SFRs via Castor V-casks. This provides an important precondition in achieving the status 'free from nuclear fuel' of the shut down German NPPs

Quivers For Special Fuel Rods-Disposal Of Special Fuel Rods In CASTOR V Casks

Energy Technology Data Exchange (ETDEWEB)

Bannani, Amin; Cebula, Wojciech; Buchmuller, Olga; Huggenberg, Roland [GNS, Essen (Germany); Helmut Kuhl [WTI, Julich (Germany)

2015-05-15

While GNS casks of the CASTOR family are a suitable means to transfer fuel assemblies (FA) from the NPP to an interim dry storage site, Germanys phase-out of nuclear energy has triggered the demand for an additional solution to dispose of special fuel rods (SFR), normally remaining in the fuel pond until the final shutdown of the NPP. SFR are fuel rods that had to be removed from fuel assemblies mainly due to their special condition, e. g. damages in the cladding of the fuel rods which may have occurred during reactor operations. SFR are usually stored in the spent fuel pond after they are removed from the FA. The quiver for special fuel rods features a robust yet simple design, with a high mechanical stability, a reliable leak-tightness and large safety margins for future requirements on safety analysis. The quiver for special fuel rods can be easily adapted to a large variety of different damaged fuel rods and tailored to the specific need of the customer. The quiver for special fuel rods is adaptable e.g. in length and diameter for use in other types of transport and storage casks and is applicable in other countries as well. The overall concept presented here is a first of its kind solution for the disposal of SFRs via Castor V-casks. This provides an important precondition in achieving the status 'free from nuclear fuel' of the shut down German NPPs.

Development of a direct methanol fuel cell system for the power segment below 5 kW; Entwicklung eines Direkt-Methanol-Brennstoffzellensystems der Leistungsklasse kleiner 5 kW

Energy Technology Data Exchange (ETDEWEB)

Noelke, M.

2006-10-20

The attractiveness of electrical conversion of liquid methanol in a fuel cell is defined by its simple storage and high energy density. Therefore, direct-methanol fuel cell (DMFC) qualifies for applications in portable systems and mobile application in the kW-class. The goal of this work is to develop and demonstrate an improved and optimized peripheral DMFC system compared to the current level of technology. The selected mobile application is the retrofit of the energy supply of a ''Scooter'' with a fuel cell system. The required size reduction and the simplification of the DMFC system are realized by an integrated concept, which combines ideally the peripheral system and the fuel cell. A profound analysis of the stack and the peripheral components is a prerequisite for an optimized design. A detailed modelling and understanding of the stack behaviour establish the starting point of this work. The influence of the most important operating parameters like stack temperature, cell voltage, current density, air ratio and methanol concentration is captured accurately by the developed model and validated by experimental data. This shapes the frame work of the following system design approach. For this the clearly defined task of the peripheral system are investigated individually for alternatives and the best option is selected for the final solution. For selecting the right pumps and blowers available products and prototypes are characterized and checked for the system requirements. The investigation and the modelling of the exhaust gas condenser lead to an optimized component design for the ''Scooter'' DMFC design. Additionally, the integration of the anode loop is accomplished consisting of the supply lines, the circulating pump, the gas separator and the exhaust line. The direct coupling of the fuel cell with a lithium-ion battery as an option for electrical conditioning is investigated. In the system modelling the influence

Boosting nuclear fuels

International Nuclear Information System (INIS)

Demarthon, F.; Donnars, O.; Dupuy-Maury, F.

2002-01-01

This dossier gives a broad overview of the present day status of the nuclear fuel cycle in France: 1 - the revival of nuclear power as a solution to the global warming and to the increase of worldwide energy needs; 2 - the security of uranium supplies thanks to the reuse of weapon grade highly enriched uranium; 3 - the fabrication of nuclear fuels from the mining extraction to the enrichment processes, the fabrication of fuel pellets and the assembly of fuel rods; 4 - the new composition of present day fuels (UO x and chromium-doped pellets); 5 - the consumption of plutonium stocks and the Corail and Apa fuel assemblies for the reduction of plutonium stocks and the preservation of uranium resources. (J.S.)

Substitution of chlorinated and fluorinated solvents by biodegradable detergent solution in components cleaning of nuclear fuel elements

International Nuclear Information System (INIS)

Vieira, Andre Luiz Pinto da Silva

2000-01-01

As the auxiliary oils used in machining evolved from integral into aqueous emulsion, and later on into aqueous-solution synthetic oils, the components cleaning process with organic solvents, originally adopted at the Fuel Element Factory (FEC), Industrias Nucleares do Brasil S.A. (INB) began to present problems in removing oil residues from machined components, due to the incompatibility between aqueous and organic media. In order to eliminate such incompatibility and adapt the process to the environmental laws restricting production and use of chlorinated or fluorinated solvents as a measure for preserving the atmosphere's ozone layer, in 1995 INB initiated the development of a components cleaning process using biodegradable aqueous detergent. The effort was completed in 2000 with the construction of a machine in keeping with the specific geometry of the fuel-assembly components and the operating conditions required for working with the new process. (author)

Study on the Conversion of Fuel Nitrogen Into NOx

Directory of Open Access Journals (Sweden)

Raminta Plečkaitienė

2011-12-01

Full Text Available The aim of this work is to investigate NOx regularities combusting fuels having high concentration of nitrogen and to develop methods that will reduce the conversion of fuel nitrogen into NOx. There are three solutions to reducing NOx concentration: the combustion of fuel mixing it with other types of “clean” fuel containing small amounts of nitrogen, laundering fuel and the combustion of fuel using carbon additives. These solutions can help with reducing the amount of nitrogen in the wood waste of furniture by about 30% by washing fuel with water. Therefore, NOx value may decrease by about 35%.Article in Lithuanian

Development of a regional concept for energy management for the region of Karlsruhe. Final report; Entwicklung eines regionalen Energiemanagement-Konzeptes und Anwendung auf die TechnologieRegion Karlsruhe. Endbericht

Energy Technology Data Exchange (ETDEWEB)

Rentz, O.; Fichtner, W.; Frank, M. [Karlsruhe Univ. (T.H.) (Germany). Inst. fuer Industriebetriebslehre und Industrielle Produktion; Wolf, M.A.; Rejman, M.; Eyerer, P. [Fraunhofer-Institut fuer Chemische Technologie (ICT) (Germany); Reimert, R.; Schulz, A.; Buren, V. v. [Karlsruhe Univ. (T.H.) (Germany). Engler-Bunte-Institut Bereich 1 - Gas, Erdoel und Kohle; Schaefers, B.; Bernart, Y. [Karlsruhe Univ. (T.H.) (DE). Institut fuer Soziologie (IfSoz) (Germany)

2002-09-01

Major objectives of this project are: to prepare a cross-disciplinary analysis of all characteristic aspects of the energy supply and demand patterns of a group of selected energy-intensive companies in the Karlsruhe and Rhine harbour area (5 industrial power consumers, 1 utility), to identify practical approaches for optimization and integration of energy and material flows, (networking), and to develop optimised investment and energy supply options within the framework of given conditions. The basis of the optimal solution and energy network presented and explained in detail is a new combined-cycle power plant running as a gas-fired CHP plant, substituting about 50% of the systems formerly used. (orig./CB) [German] Fragestellungen der Effizienzsteigerung und der Verwertung von Abfaellen und Abwaerme gewinnen an Relevanz vor dem Hintergrund der begrenzten Aufnahmekapazitaet der Umweltmedien fuer Schadstoffe. Im Rahmen des Projektes wurde am Beispiel der Region Karlsruhe (5 Industrieunternehmen und 1 EVU) die Entwicklung betriebsuebergreifender Energieversorgungssysteme (Netzwerke) interdisziplinaer analysiert und beschrieben. Zielsetzungen des Projekts waren unter anderem: Bestimmung von zukunftsfaehigen Optionen, intelligente Vernetzung von Energiestroemen, wirtschaftliche Optimierung betriebsuebergreifender Energiemanagement-Loesungen. Die optimale vorgestellte Loesung ist charakterisiert durch den Neubau einer zentralen, gasgefeuerten GuD-Anlage, die etwa die Haelfte der bisherigen Anlagen ersetzt und zusammen mit den weiterhin genutzten Anlagen die Energieversorgung der Unternehmen sicherstellt. (orig./CB)

Final report on the development of a disturbanceless NDE compact cooling device; Abschlussbericht zur Entwicklung einer stoerarmen maschinellen NDE-Kompaktkuehlung

Energy Technology Data Exchange (ETDEWEB)

Kaiser, G.

2002-08-13

The project comprised the following aspects: 1. Development of a disturbance-free, mechanized compact cooling system for a NDE measuring system on the basis of a commercial SL200-10 split stirling cooling system of AEG Infrarotmodule GmbH, Heilbronn; 2. Support of the development work at the HTSL/Hall magnetometer of Friedrich-Schiller University, Jena; 3. Measurements of HTSL/Hall magnetometer samples and thermal characterisation. [German] Im Rahmen dieses Vorhabens wurden die folgenden Aufgabenstellungen behandelt: 1. Entwicklung einer stoerarmen, maschinellen Kompaktkuehlung fuer ein NDE-Messsystem auf der Basis eines kommerziellen Split-Stirlingkuehlers SL200-10 der Firma AEG Infrarotmodule GmbH, Heilbronn, 2. Unterstuetzung der Entwicklungsarbeiten am HTSL/Hall-Magnetometer, die bei der Friedrich-Schiller-Universitaet in Jena durchgefuehrt wurden, 3. Messungen an HTSL/Hall-Magnetometer-Proben zu deren thermischer Charakterisierung. (orig.)

Status reports on the development and application of acoustic emission analysis. Proceedings; Statusberichte zur Entwicklung und Anwendung der Schallemissionsanalyse. Beitraege

Energy Technology Data Exchange (ETDEWEB)

NONE

2017-08-01

The colloquium lectures represent the wide range of applications in acoustic emission analysis and testing in the areas of damage development and damage mechanisms, testing of components, condition monitoring, development of new measuring systems and sensors as well as software development regarding locating methods and signal analysis. One focus of the colloquium is on current hardware and software developments for status monitoring by means of AE monitoring. One of the papers was separately analyzed for this database. [German] Die Vortraege des Kolloquiums repraesentieren das breite Spektrum der Anwendungen der Schallemissionsanalyse und -pruefung in den Bereichen der Schadensentwicklung und Schadensmechanismen, Pruefung von Bauteilen, Zustandsueberwachung, Entwicklung neuer Messsysteme und Sensoren sowie Softwareentwicklung bezueglich Ortungsverfahren und Signalanalyse. Ein Schwerpunkt des Kolloquiums betrifft aktuelle Hard- und Softwareentwicklungen zur Zustandsueberwachung durch AE-Monitoring.

Elastic plastic analysis of fuel element assemblies - hexagonal claddings and fuel rods

International Nuclear Information System (INIS)

Mamoun, M.M.; Wu, T.S.; Chopra, P.S.; Rardin, D.C.

1979-01-01

Analytical studies have been conducted to investigate the structural, thermal, and mechanical behavior of fuel rods, claddings and fuel element assemblies of several designs for a conceptual Safety Test Facility (STF). One of the design objectives was to seek a geometrical configuration for a clad by maximizing the volume fraction of fuel and minimizing the resultant stresses set-up in the clad. The results of studies conducted on various geometrical configurations showed that the latter design objective can be achieved by selecting a clad of an hexagonal geometry. The analytical studies necessitated developing solutions for determining the stresses, strains, and displacements experienced by fuel rods and an hexagonal cladding subjected to thermal fuel-bowing loads acting on its internal surface, the external pressure of the coolant, and elevated temperatures. This paper presents some of the initially formulated analytical methods and results. It should be emphasized that the geometrical configuration considered in this paper may not necessarily be similar to that of the final design. Several variables have been taken into consideration including cladding thickness, the dimensions of the fuel rod, the temperature of the fuel and cladding, the external pressure of the cooling fluid, and the mechanical strength properties of fuel and cladding. A finite-element computer program, STRAW Code, has also been employed to generate several numerical results which have been compared with those predicted by employing the initially formulated solutions. The theoretically predicted results are in good agreement with those of the STRAW Code. (orig.)

Fuel fabrication and reprocessing for nuclear fuel cycle with inherent safety demands

Energy Technology Data Exchange (ETDEWEB)

Shadrin, Andrey Yurevich; Dvoeglazov, Konstantin Nikolaevich; Ivanov, Valentine Borisovich; Volk, Vladimir Ivanovich; Skupov, Mikhail Vladimirovich; Glushenkov, Alexey Evgenevich [Joint Stock Company ' ' The High Technological Research Institute of Inorganic Materials' ' , Moscow (Russian Federation); Troyanov, Vladimir Mihaylovich; Zherebtsov, Alexander Anatolievich [Innovation and Technology Center of Project ' ' PRORYV' ' , State Atomic Energy Corporation ' ' Rosatom' ' , Moscow (Russian Federation)

2015-06-01

The strategies adopted in Russia for a closed nuclear fuel cycle with fast reactors (FR), selection of fuel type and recycling technologies of spent nuclear fuel (SNF) are discussed. It is shown that one of the possible technological solutions for the closing of a fuel cycle could be the combination of pyroelectrochemical and hydrometallurgical methods of recycling of SNF. This combined scheme allows: recycling of SNF from FR with high burn-up and short cooling time; decreasing the volume of stored SNF and the amount of plutonium in a closed fuel cycle in FR; recycling of any type of SNF from FR; obtaining the high pure end uranium-plutonium-neptunium end-product for fuel refabrication using pellet technology.

Alternative fuels, fuel cycles, and reactors: are they useful. are they necessary

International Nuclear Information System (INIS)

Spinrad, B.I.

1985-01-01

This chapter discusses reactors, fuel cycles, and fuel production concepts other than those considered conventional in the nuclear community. An attempt is made to look for improvements with the aim of providing cheaper and more durable energy systems, and to contribute toward a solution of the threat of weapons material diversion and weapons proliferation problems. Topics considered include breeding, alternate breeder cycles, alternative reprocessing schemes, symbiotic reactor systems, an interim strategy, and other sources of nuclear fuel. It is determined that the reprocessing of spent fuel is an important safeguard measure in itself

Global Spent Fuel Logistics Systems Study (GSFLS). Volume 4. Pacific basin spent fuel logistics system

International Nuclear Information System (INIS)

1978-06-01

This report summarizes the conceptual framework for a Pacific Basin Spent Fuel Logistics System (PBSFLS); and preliminarily describes programatic steps that might be taken to implement such a system. The PBSFLS concept is described in terms of its technical and institutional components. The preferred PBSFLS concept embodies the rationale of emplacing a fuel cycle system which can adjust to the technical and institutional non-proliferation solutions as they are developed and accepted by nations. The concept is structured on the basis of initially implementing a regional spent fuel storage and transportation system which can technically and institutionally accommodate downstream needs for energy recovery and long-term waste management solutions

Alternatives for nuclear fuel disposal

International Nuclear Information System (INIS)

Ramirez S, J. R.; Badillo A, V.; Palacios H, J.; Celis del Angel, L.

2010-10-01

The spent fuel is one of the most important issues in the nuclear industry, currently spent fuel management is been cause of great amount of research, investments in the construction of repositories or constructing the necessary facilities to reprocess the fuel, and later to recycle the plutonium recovered in thermal reactors. What is the best solution? or, What is the best technology for a specific solution? Many countries have deferred the decision on selecting an option, while other works actively constructing repositories and others implementing the reprocessing facilities to recycle the plutonium obtained from nuclear spent fuel. In Mexico the nuclear power is limited to two reactors BWR type and medium size. So the nuclear spent fuel discharged has been accommodated at reactor's spent fuel pools. Originally these pools have enough capacity to accommodate spent fuel for the 40 years of designed plant operation. However, currently is under process an extended power up rate to 20% of their original power and also there are plans to extend operational life for 20 more years. Under these conditions there will not be enough room for spent fuel in the pools. So this work describes some different alternatives that have been studied in Mexico to define which will be the best alternative to follow. (Author)

Spray-on polyvinyl alcohol separators and impact on power production in air-cathode microbial fuel cells with different solution conductivities

KAUST Repository

Hoskins, Daniel L.

2014-11-01

© 2014 Elsevier Ltd. Separators are used to protect cathodes from biofouling and to avoid electrode short-circuiting, but they can adversely affect microbial fuel cell (MFC) performance. A spray method was used to apply a polyvinyl alcohol (PVA) separator to the cathode. Power densities were unaffected by the PVA separator (339 ± 29 mW/m2), compared to a control lacking a separator in a low conductivity solution (1mS/cm) similar to wastewater. Power was reduced with separators in solutions typical of laboratory tests (7-13 mS/cm), compared to separatorless controls. The PVA separator produced more power in a separator assembly (SEA) configuration (444 ± 8 mW/m2) in the 1mS/cm solution, but power was reduced if a PVA or wipe separator was used in higher conductivity solutions with either Pt or activated carbon catalysts. Spray and cast PVA separators performed similarly, but the spray method is preferred as it was easier to apply and use.

The cost of spent fuel storage

Energy Technology Data Exchange (ETDEWEB)

Ramirez S, J. R.; Palacios H, J. C.; Badillo, V.; Alonso, G., E-mail: ramon.ramirez@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

2011-11-15

Spent fuel is one of the most important issues in the nuclear industry, currently spent fuel management is been cause of great amount of research, investments, constructing repositories or constructing the necessary facilities to reprocess the fuel, and later to recycle the plutonium recovered in thermal reactors. What is the best solution?, or What is the best technology for an specific solution? Many countries have deferred the decision on selecting an option, while others works actively constructing repositories and others implementing the reprocessing facilities to recycle the plutonium obtained from nuclear spent fuel. In Mexico the nuclear power is limited to two reactors BWR type and medium size. So the nuclear spent fuel discharged has been accommodated at reactor's spent fuel pools. Originally these pools have enough capacity to accommodate spent fuel for the 40 years of designed plant operation. However currently, the plants are under a process for extended power up-rate to 20% of original power and also there are plans to extended operational life for 20 more years. Under these conditions there will not be enough room for spent fuel in the pools. (Author)

Erkundungen im Spannungsfeld von Pädagogik, Spielspass und technischer Machbarkeit. Gedanken zur Konzeption und Entwicklung spielbasierter digitaler Lernumgebung

Directory of Open Access Journals (Sweden)

Florian Berger

2009-02-01

Full Text Available Computerspiele sind heute aus der digitalen Medienwelt nicht mehr wegzudenken. Ihre rasante technische Entwicklung sowie ihre hohe Akzeptanz in der Jugendkultur werfen Fragen nach pädagogischer Verwertbarkeit dieses Mediums auf. Auf diesem Gebiet besteht Forschungsbedarf: Für den Einsatz aktueller Spielkonzepte als Lehrmittel existieren keine fundierten Theorien oder Konzepte. Der schöpferische Umgang mit Spielen durch Anwender («Emergent Gameplay» bietet hier durch sein hohes Motivationspotential einen vielversprechenden Ansatz. Die oft wenig beachtete Rolle der digitalen Spielen zugrunde liegenden Softwaretechnik sollte stärkere Berücksichtigung finden: Es existiert einerseits ein für die Akzeptanz beim Anwender notwendiges Minimum, andererseits ist der Einsatz des aktuellen technischen «state of the art» für die Umsetzung pädagogischer und didaktischer Ambitionen durch seine enormen Anforderungen wenig zielführend. Im Ergebnis sind Idee und Spielspass das Mass auch für Anwendungen des Game Based Learn­ing.

A new coupled system for BWR nuclear fuel management

International Nuclear Information System (INIS)

Castillo, A.; Ortiz-Servin, J.J.; Montes-Tadeo, J.L.; Perusquia, R.; Rizos, R.L.M.

2015-01-01

In this work, a system to solve four stages of the fuel management problem is showed.The system uses different heuristic techniques to solve each stage of that area, and this problem is solved in a coupled way. Considered problems correspond to the following designs: fuel lattice, fuel assembly, fuel reload and control rod patterns. Even though, each stage of the problem can have its own objective function, the complete problem was solved using a multi-objective function. The solution strategy is to solve each stage of design in an iterative process, taking into account previous results for the next stage, until to achieve a complete solution. The solution strategy to solve the coupled problem is the following: the first solved stage is the fuel lattice design, the second one is fuel assembly design, finally an internal loop between both fuel reload design and control rod pattern design is carried out.For this internal loop, a seed reload using Haling principle is generated. The obtained results showed the advantage to solve the whole problem in a coupled way. (author)

Water Reactor Fuel Performance Meeting 2008

International Nuclear Information System (INIS)

2008-10-01

This meeting contains articles of the Water Reactor Fuel Performance Meeting 2008 of Korean Nuclear Society, Atomic Energy Society of Japan, Chinese Nuclear Society, European Nuclear Society and American Nuclear Society. It was held on Oct. 19-23, 2008 in Seoul, Korea and subject of Meeting is 'New Clear' Fuel - A green energy solution. This proceedings is comprised of 5 tracks. The main topic titles of track are as follows: Advances in water reactor fuel technology, Fuel performance and operational experience, Transient fuel behavior and safety-related issues, Fuel cycle, spent fuel storage and transportations and Fuel modeling and analysis. (Yi, J. H.)

Road transport fuels in europe: the explosion of demand for diesel fuel

International Nuclear Information System (INIS)

Bensaid, B.

2004-01-01

In the last 20 years, road transport fuel consumption has more than doubled in European countries, due to strong growth on the diesel passenger car segment and in the transport of road freight. In an economy heavily dependent on oil, European authorities are seeking to promote alternative energy solutions, such as motor fuels produced from biomass

Coal-water fuels - a clean coal solution for Eastern Europe

International Nuclear Information System (INIS)

Ljubicic, B.; Willson, W.; Bukurov, Z.; Cvijanovic, P.; Stajner, K.; Popovic, R.

1993-01-01

Eastern Europe currently faces great economic and environmental problems. Among these problems is energy provision. Coal reserves are large but cause pollution while oil and gas need to be used for export. Formal 'clean coal technologies' are simply too expensive to be implemented on a large scale in the current economic crisis. The promised western investment and technological help has simply not taken place, western Europe must help eastern Europe with coal technology. The cheapest such technology is coal-water fuel slurry. It can substitute for oil, but research has not been carried out because of low oil prices. Coal-water fuel is one of the best methods of exploiting low rank coal. Many eastern European low rank coals have a low sulfur content, and thus make a good basis for a clean fuel. Italy and Russia are involved in such a venture, the slurry being transported in a pipeline. This technology would enable Russia to exploit Arctic coal reserves, thus freeing oil and gas for export. In Serbia the exploitation of sub-Danube lignite deposits with dredging mining produced a slurry. This led to the use and development of hot water drying, which enabled the removal of many of the salts which cause problems in pulverized fuel combustion. The system is economic, the fuel safer to transport then oil, either by rail or in pipelines. Many eastern European oil facilities could switch. 24 refs

Proportioning of 79Se and 126Sn long life radionuclides in the fission products solutions coming from spent fuels processing

International Nuclear Information System (INIS)

Comte, J.

2001-11-01

The determination of radionuclides present in waste resulting from the nuclear fuel reprocessing is a request from the regulatory authorities to ensure an optimal management of the storage sites. Long-lived radionuclides (T 1/2 > 30 years) are particularly concerned owing to the fact that their impact must be considered for the long term. Safety studies have established a list of long-lived radionuclides (LLRN) whose quantification is essential for the management of the disposal site. Among these, several are pure β emitters, present at low concentration levels in complex matrices. Their determination, by radiochemical method or mass spectrometry, involves selective chemical separations from the others β/γ emitters and from the measurement interfering elements. The work undertaken in this thesis relates to the development of analytical methods for the determination of two long-lived radionuclides: selenium 79 and tin 126, in acid solutions of fission products present in nuclear fuel reprocessing plant. For selenium 79, a β emitter with a half live estimated to be 10 6 years, the bibliography describes different chemical separation methods including precipitation, liquid-liquid extraction and chromatography on ionic resins. After optimisation on a synthetic solution, two of these techniques, precipitation by potassium iodine and separation with ion exchange resins were applied to a genuine solution of fission products at Cogema La Hague. The results showed that only the ion exchange method allows us to obtain a solution sufficiently decontaminated (FDβγ = 250) with a significant selenium recovery yield (85%). This separation allows the measurement of the 79 Se by electrothermal vaporization coupled with inductively coupled plasma mass spectrometry (ETV-ICP/MS), after transfer of the samples to CEA/Cadarache. The concentration of 79 Se measured is 0,42 mg/L in the solution of fission products with an isotopic ratio 79 Se/ 82 Se equal to that recommended by the

Modeling the Thermal Rocket Fuel Preparation Processes in the Launch Complex Fueling System

Directory of Open Access Journals (Sweden)

A. V. Zolin

2015-01-01

Full Text Available It is necessary to carry out fuel temperature preparation for space launch vehicles using hydrocarbon propellant components. A required temperature is reached with cooling or heating hydrocarbon fuel in ground facilities fuel storages. Fuel temperature preparing processes are among the most energy-intensive and lengthy processes that require the optimal technologies and regimes of cooling (heating fuel, which can be defined using the simulation of heat exchange processes for preparing the rocket fuel.The issues of research of different technologies and simulation of cooling processes of rocket fuel with liquid nitrogen are given in [1-10]. Diagrams of temperature preparation of hydrocarbon fuel, mathematical models and characteristics of cooling fuel with its direct contact with liquid nitrogen dispersed are considered, using the numerical solution of a system of heat transfer equations, in publications [3,9].Analytical models, allowing to determine the necessary flow rate and the mass of liquid nitrogen and the cooling (heating time fuel in specific conditions and requirements, are preferred for determining design and operational characteristics of the hydrocarbon fuel cooling system.A mathematical model of the temperature preparation processes is developed. Considered characteristics of these processes are based on the analytical solutions of the equations of heat transfer and allow to define operating parameters of temperature preparation of hydrocarbon fuel in the design and operation of the filling system of launch vehicles.The paper considers a technological system to fill the launch vehicles providing the temperature preparation of hydrocarbon gases at the launch site. In this system cooling the fuel in the storage tank before filling the launch vehicle is provided by hydrocarbon fuel bubbling with liquid nitrogen. Hydrocarbon fuel is heated with a pumping station, which provides fuel circulation through the heat exchanger-heater, with

Particle Swarm Optimization applied to combinatorial problem aiming the fuel recharge problem solution in a nuclear reactor

International Nuclear Information System (INIS)

Meneses, Anderson Alvarenga de Moura; Schirru, Roberto

2005-01-01

This work focuses on the usage the Artificial Intelligence technique Particle Swarm Optimization (PSO) to optimize the fuel recharge at a nuclear reactor. This is a combinatorial problem, in which the search of the best feasible solution is done by minimizing a specific objective function. However, in this first moment it is possible to compare the fuel recharge problem with the Traveling Salesman Problem (TSP), since both of them are combinatorial, with one advantage: the evaluation of the TSP objective function is much more simple. Thus, the proposed methods have been applied to two TSPs: Oliver 30 and Rykel 48. In 1995, KENNEDY and EBERHART presented the PSO technique to optimize non-linear continued functions. Recently some PSO models for discrete search spaces have been developed for combinatorial optimization. Although all of them having different formulation from the ones presented here. In this paper, we use the PSO theory associated with to the Random Keys (RK)model, used in some optimizations with Genetic Algorithms. The Particle Swarm Optimization with Random Keys (PSORK) results from this association, which combines PSO and RK. The adaptations and changings in the PSO aim to allow the usage of the PSO at the nuclear fuel recharge. This work shows the PSORK being applied to the proposed combinatorial problem and the obtained results. (author)

Numerical solution of diffusion equation to study fast neutrons flux distribution for variant radii of nuclear fuel pin and moderator regions

Energy Technology Data Exchange (ETDEWEB)

Mousavi Shirazi, Seyed Alireza [Islamic Azad Univ. (I.A.U.), Dept. of Physics, Tehran (Iran, Islamic Republic of)

2015-07-15

In this symbolic investigation, a cylindrical cell in a LWR, which consists of one fuel pin and moderator (water), is considered. The width of this cylindrical cell is divided into 100 equal units. Since the neutron flux in a cylindrical fuel pin is resulting from the diffusion equation: -(1)/(r)(d)/(dr)Dr(d)/(dr)φ(r) + Σ{sub a}φ(r) = S(r), the amount of fast neutron fluxes are obtained on the basis of the numeric solution of this equation, and the applied boundary conditions are considered: φ'(0) = φ'(1) = 0. This differential equation is solved by the tridiagonal method for variant enrichments of uranium. Neutron fluxes are obtained in variant radii of fuel pin and moderator and are finally compared with each other. There are some interesting outcomes resulting from this investigation. It can be inferred that because of the fuel enrichment increment, the fast neutron flux increases significantly at the centre of core, while many of the fast neutrons produced are absorbed after entering the water region, moderation of lots of them causes the reduced neutron flux to get improved in this region.

Application of laser-optical diagnostics for the support of direct-injection gasoline combustion process development; Einsatz laseroptischer Messverfahren zur Unterstuetzung der Entwicklung von Brennverfahren mit Benzin-Direkteinspritzung

Energy Technology Data Exchange (ETDEWEB)

Hentschel, W.; Meyer, H.; Stiebels, B. [Volkswagenwerk AG, Wolfsburg (Germany). Abt. Forschung und Entwicklung

2000-07-01

The development of direct-injection gasoline engines at Volkswagen was supported strictly from the beginning by the means of optical diagnostics and CFD-simulations. Basic phenomena, such as the formation of the in-cylinder flow field, the penetration of the spray formed by a hollow-cone swirl-type injector at high fuel pressure, the interaction of spray and flow and the formation of an ignitable mixture were analysed in details. The paper describes the laser-optical techniques-particle-image-velocimetry, laser-Doppler-anemometry, videostroboscopy, high-speed cinematography and laser-induced fluorescence - which were used during the development of the DI gasoline combustion process. Examples taken from engines with optical access to the combustion chamber demonstrate the capability of the techniques and pinpoint where the design of the combustion process benefits from experimental and simulation investigations. (orig.) [German] Die Entwicklung von Ottomotoren mit Benzin-Direkteinspritzung wurde bei Volkswagen von Beginn an konsequent durch den Einsatz optischer Messverfahren und CFD-Simulationen unterstuetzt. Damit konnten grundlegende Phaenomene, wie die Ausbildung des Stroemungsfeldes im Motorbrennraum, die Ausbreitung des durch einen Hohlkegel-Drallinjektor unter hohem Druck eingespritzten Kraftstoffs sowie die Wechselwirkung der Luftstroemung im Zylinder mit den Einspritzstrahlen und die Bildung einer zuendfaehigen Ladungswolke detailliert untersucht werden. Das Paper beschreibt die laseroptischen Messverfahren - Particle-Image-Velocimetry, Laser-Doppler-Anemometry, Video-Stroboskopie, Hochgeschwindikgkeits-Kinematographie und Laserinduzierte Fluoreszenz - die bei der Brennverfahrensentwicklung eingesetzt werden und zeigt anhand einer Reihe von konkreten Beispielen, wo Antworten auf Grundsatzfragen zur Auslegung des Brennverfahrens durch Messergebnisse an optisch zugaenglichen Motoren und durch CFD-Simulationen erarbeitet werden koennen. (orig.)

A study of solute transport of radiolysis products in crud and its effects on crud growth on PWR fuel pin

Energy Technology Data Exchange (ETDEWEB)

Joe, Justin H. [BNF Consulting (United States); Kim, Seung Jun, E-mail: skim@lanl.gov [Mechanical and Thermal Engineering Group (AET-1), Los Alamos National Laboratory (United States); Jones, Barclay G. [Department of Nuclear Plasma Radiological Engineering, University of Illinois Urbana-Champaign (United States)

2016-04-15

Highlights: • We model a 3-D numerical solute transport within crud deposit on PWR fuel pin. • Source term effect from radiolysis yield and recombination is minimal. • Lower crud porosity leads substantially higher concentration of solutes. • Thicker crud deposit generates substantially higher concentration of solutes. • High concentration of radiolysis species (H{sub 2}, O{sub 2}, and H{sub 2}O{sub 2}) can be directly related to corrosion issues on fuel cladding. - Abstract: This research examines the concentration of radiolysis species (H{sub 2}, O{sub 2}, and H{sub 2}O{sub 2}) over the porous crud layer using a three dimensional time dependent solute transport model. A Monte Carlo random walk technique is adopted to simulate the transport behavior of the different species with various parametric studies of source term, crud thickness, and crud porosity. Particularly, this model employs a system of coupled mass transport and chemical interactions as the source term, which makes the problem non-linear. It is demonstrated that a negligible effect on radiolysis species concentrations change due to the consideration of source term. The crud thickness and porosity effect on the concentration distributions are notably observed. In general, higher concentration starts from the intersection of the heating surface with the chimney wall from the beginning and it reaches the equilibrium state within tens of seconds. The concentration profiles of the radiolysis species H{sub 2}, O{sub 2}, and H{sub 2}O{sub 2} can be directly related to corrosion issues. The direct application of this study to nuclear engineering research is to aid in the design of reactors with higher performance without experiencing an Axial Offset Anomaly (AOA), an unexpected measured shift in axial power distribution from predicted values.

A study of solute transport of radiolysis products in crud and its effects on crud growth on PWR fuel pin

International Nuclear Information System (INIS)

Joe, Justin H.; Kim, Seung Jun; Jones, Barclay G.

2016-01-01

Highlights: • We model a 3-D numerical solute transport within crud deposit on PWR fuel pin. • Source term effect from radiolysis yield and recombination is minimal. • Lower crud porosity leads substantially higher concentration of solutes. • Thicker crud deposit generates substantially higher concentration of solutes. • High concentration of radiolysis species (H 2 , O 2 , and H 2 O 2 ) can be directly related to corrosion issues on fuel cladding. - Abstract: This research examines the concentration of radiolysis species (H 2 , O 2 , and H 2 O 2 ) over the porous crud layer using a three dimensional time dependent solute transport model. A Monte Carlo random walk technique is adopted to simulate the transport behavior of the different species with various parametric studies of source term, crud thickness, and crud porosity. Particularly, this model employs a system of coupled mass transport and chemical interactions as the source term, which makes the problem non-linear. It is demonstrated that a negligible effect on radiolysis species concentrations change due to the consideration of source term. The crud thickness and porosity effect on the concentration distributions are notably observed. In general, higher concentration starts from the intersection of the heating surface with the chimney wall from the beginning and it reaches the equilibrium state within tens of seconds. The concentration profiles of the radiolysis species H 2 , O 2 , and H 2 O 2 can be directly related to corrosion issues. The direct application of this study to nuclear engineering research is to aid in the design of reactors with higher performance without experiencing an Axial Offset Anomaly (AOA), an unexpected measured shift in axial power distribution from predicted values.

Nuclear fuel conversion and fabrication chemistry

International Nuclear Information System (INIS)

Lerch, R.E.; Norman, R.E.

1984-01-01

Following irradiation and reprocessing of nuclear fuel, two operations are performed to prepare the fuel for subsequent reuse as fuel: fuel conversion, and fuel fabrication. These operations complete the classical nuclear fuel cycle. Fuel conversion involves generating a solid form suitable for fabrication into nuclear fuel. For plutonium based fuels, either a pure PuO 2 material or a mixed PuO 2 -UO 2 fuel material is generated. Several methods are available for preparation of the pure PuO 2 including: oxalate or peroxide precipitation; or direct denitration. Once the pure PuO 2 is formed, it is fabricated into fuel by mechanically blending it with ceramic grade UO 2 . The UO 2 can be prepared by several methods which include direct denitration. ADU precipitation, AUC precipitation, and peroxide precipitation. Alternatively, UO 2 -PuO 2 can be generated directly using coprecipitation, direct co-denitration, or gel sphere processes. In coprecipitation, uranium and plutonium are either precipitated as ammonium diuranate and plutonium hydroxide or as a mixture of ammonium uranyl-plutonyl carbonate, filtered and dried. In direct thermal denitration, solutions of uranium and plutonium nitrates are heated causing concentration and, subsequently, direct denitration. In gel sphere conversion, solutions of uranium and plutonium nitrate containing additives are formed into spherical droplets, gelled, washed and dried. Refabrication of these UO 3 -PuO 2 starting materials is accomplished by calcination-reduction to UO 2 -PuO 2 followed by pellet fabrication. (orig.)

Liquid-Feed Methanol Fuel Cell With Membrane Electrolyte

Science.gov (United States)

Surampudi, Subbarao; Narayanan, S. R.; Halpert, Gerald; Frank, Harvey; Vamos, Eugene

1995-01-01

Fuel cell generates electricity from direct liquid feed stream of methanol/water solution circulated in contact with anode, plus direct gaseous feed stream of air or oxygen in contact with cathode. Advantages include relative simplicity and elimination of corrosive electrolytic solutions. Offers potential for reductions in size, weight, and complexity, and for increases in safety of fuel-cell systems.

The system architecture for renewable synthetic fuels

DEFF Research Database (Denmark)

Ridjan, Iva

To overcome and eventually eliminate the existing heavy fossil fuels in the transport sector, there is a need for new renewable fuels. This transition could lead to large capital costs for implementing the new solutions and a long time frame for establishing the new infrastructure unless a suitable...... and production plants, so it is important to implement it in the best manner possible to ensure an efficient and flexible system. The poster will provide an overview of the steps involved in the production of synthetic fuel and possible solutions for the system architecture based on the current literature...

Experience of Areva in fuel services for PWR and BWR

International Nuclear Information System (INIS)

Morales, I.

2015-01-01

AREVA being an integrated supplier of fuel assemblies has included in its strategy to develop services and solutions to customers who desire to improve the performance and safety of their fuel. These services go beyond the simple 'after sale' services that can be expected from a fuel supplier: The portfolio of AREVA includes a wide variety of services, from scientific calculations to fuel handling services in a nuclear power plant. AREVA is committed to collaborate and to propose best-in-class solutions that really make the difference for the customer, based on 40 years of Fuel design and manufacturing experience. (Author)

recovery of enriched uranium from waste solution obtained from fuel fabrication laboratories

International Nuclear Information System (INIS)

Othman, S.H.A.

2003-01-01

reversed-phase partition chromatography is shown to be a convenient and applicable method for the quantitative recovery of uranium (19.7% enriched with 235 U) from highly impure solution . the processing of uranium compounds for atomic energy project especially in FMPP(Egyptian fuel manufacture pilot plant) gives rise to a variety of wastes in which the uranium content is of considerable importance. the recovery of uranium from concentrated mother liquors produced from ADU (ammonium diuranate ) precipitation, as well as those due to ADU washing is studied in this work. column of poly-trifluoro-monochloro-ethilene (Kel-F) supporting tri-n-butyl-phosphate (TBP) retains uranium .impurities are eluted with 6.5 M HCl, and the uranium is eluted with water and the recovery of uranium is better than 94%. A mathematical model was suggested to stimulate the sorption process of uranium ions (or any other ion ) by column of solvent impregnated resin containing organic extractant (the same as the previous column) . An excellent agreement was founded between the experimental results and the mathematical model

SPES, Fuel Cycle Optimization for LWR

International Nuclear Information System (INIS)

1973-01-01

1 - Nature of physical problem solved: Determination of optimal fuel cycle at equilibrium for a light water reactor taking into account batch size, fuel enrichment, de-rating, shutdown time, cost of replacement energy. 2 - Method of solution: Iterative method

Simultaneous determination of uranium and plutonium in dissolver solution of irradiated fuel, using ID-TIMS. IRP-11

International Nuclear Information System (INIS)

Shah, Raju; Sasi Bhushan, K.; Govindan, R.; Alamelu, D.; Khodade, P.S.; Aggarwal, S.K.

2007-01-01

A simple sample preparation and simultaneous analysis method to determine uranium and plutonium from dissolver solution, employing the technique of Isotope Dilution Mass spectrometry has been demonstrated. The method used, co-elusion of Uranium and Plutonium from anion exchanger column after initial elution of major part of uranium in 1:5 HNO 3 in order to reduce the initial U/Pu ratio from 1000 to about 100-200 in the co-eluted fraction. Due to the availability of variable multi-collector system, different Faraday cups were adjusted to collect the different ion intensities corresponding to the different masses, during the simultaneous analysis of Uranium and Plutonium, loaded on Re double filament assembly. 233 U and PR grade Plutonium were used as spikes to determine Uranium and Plutonium from dissolver solution of irradiated fuel from research reactor. The possibility of getting the isotopic composition of uranium from the simultaneous analysis of co-eluted purified fraction of U and Pu from spiked aliquots is also explained. (author)

Identical location transmission electron microscopy in combination with rotating disc electrode measurements. The activity of fuel cell catalysts and their degradation

Energy Technology Data Exchange (ETDEWEB)

Schloegl, Katrin G.

2011-07-13

As an alternative to conventional combustion engines, the Proton Exchange Membrane Fuel Cell (PEMFC) using hydrogen as a fuel is a promising concept owing to its potential independence from fossil fuels, high efficiency and zero emissions. Concerning its commercial viability, the fundamental problem of high system cost per power output and lifetime is closely related to finding more active and stable catalysts for the oxygen reduction reaction. In the presented work, several methods are combined to examine the parameters and processes responsible for both activity and degradation of platinum-based catalysts. Degradation mechanisms are scrutinized by means of electrochemical measurements with the rotating disc electrode in combination with a recently developed TEM technique, which allows for the comparison of identical locations before and after accelerated stress tests. (orig.) [German] Die mit Wasserstoff betriebene Proton Exchange Membrane Brennstoffzelle (PEMFC) stellt aufgrund ihrer potentiellen Unabhaengigkeit von fossilen Energietraegern, ihrem hohen Wirkungsgrad und fehlendem Schadstoffausstoss eine vielversprechende Alternative zum konventionellen Verbrennungsmotor dar. Das grundlegende Problem der zu hohen Systemkosten und zu geringen Lebensdauer fuer kommerzielle Anwendungen ist eng mit der Entwicklung aktiverer und stabiler Elektrokatalysatoren fuer die Sauerstoffreduktion verknuepft. In der vorliegenden Arbeit werden verschiedene Methoden kombiniert, um die Parameter und Prozesse zu untersuchen, welche fuer die Aktivitaet und Degradation platinbasierter Katalysatoren verantwortlich sind. Zur Aufklaerung vorliegender Degradationsmechanismen werden elektrochemische Messungen mit der rotierenden Scheibenelektrode in Kombination mit einer neu entwickelten TEM Methode eingesetzt, welche es ermoeglicht, identische Stellen vor und nach beschleunigten Degradationstests zu untersuchen.

Commercial solutions [for dry spent fuel storage casks

International Nuclear Information System (INIS)

Howe, W.F.; Pennington, C.W.; Hobbs, J.; Lee, W.; Thomas, B.D.; Dibert, D.J.

1996-01-01

In the aftermath of the termination of the DOE's MPC (Multi-Purpose Canister) programme, commercial suppliers are coming forward with new or updated systems to meet utility needs. Leading vendors describe the advantages of their systems for dry spent fuel storage and transport. (Author)

Nalco Fuel Tech

Energy Technology Data Exchange (ETDEWEB)

Michalak, S.

1995-12-31

The Nalco Fuel Tech with its seat at Naperville (near Chicago), Illinois, is an engineering company working in the field of technology and equipment for environmental protection. A major portion of NALCO products constitute chemical materials and additives used in environmental protection technologies (waste-water treatment plants, water treatment, fuel modifiers, etc.). Basing in part on the experience, laboratories and RD potential of the mother company, the Nalco Fuel Tech Company developed and implemented in the power industry a series of technologies aimed at the reduction of environment-polluting products of fuel combustion. The engineering solution of Nalco Fuel Tech belong to a new generation of environmental protection techniques developed in the USA. They consist in actions focused on the sources of pollutants, i.e., in upgrading the combustion chambers of power engineering plants, e.g., boilers or communal and/or industrial waste combustion units. The Nalco Fuel Tech development and research group cooperates with leading US investigation and research institutes.

Probable leaching mechanisms for spent fuel

International Nuclear Information System (INIS)

Wang, R.; Katayama, Y.B.

1981-01-01

At the Pacific Northwest Laboratory, researchers in the Waste/Rock Interaction Technology Program are studying spent fuel as a possible waste form for the Office of Nuclear Waste Isolation. This paper presents probable leaching mechanisms for spent fuel and discusses current progress in identifying and understanding the leaching process. During the past year, experiments were begun to study the complex leaching mechanism of spent fuel. The initial work in this investigation was done with UO 2 , which provided the most information possible on the behavior of the spent-fuel matrix without encountering the very high radiation levels associated with spent fuel. Both single-crystal and polycrystalline UO 2 samples were used for this study, and techniques applicable to remote experimentation in a hot cell are being developed. The effects of radiation are being studied in terms of radiolysis of water and surface activation of the UO 2 . Dissolution behavior and kinetics of UO 2 were also investigated by electrochemical measurement techniques. These data will be correlated with those acquired when spent fuel is tested in a hot cell. Oxidation effects represent a major area of concern in evaluating the stability of spent fuel. Dissolution of UO 2 is greatly increased in an oxidizing solution because the dissolution is then controlled by the formation of hexavalent uranium. In solutions containing very low oxygen levels (i.e., reducing solutions), oxidation-induced dissolution may be possible via a previously oxidized surface, through exposure to air during storage, or by local oxidants such as O 2 and H 2 O 2 produced from radiolysis of water and radiation-activated UO 2 surfaces. The effects of oxidation not only increase the dissolution rate, but could lead to the disintegration of spent fuel into fine fragments

WELWING, Material Buckling for HWR with Annular Fuel Elements

International Nuclear Information System (INIS)

Grosskopf, O.G.P.

1973-01-01

1 - Nature of the physical problem solved: WELWING was developed to calculate the material buckling of reactor systems consisting of annular fuel elements in heavy water as moderator for various moderator to fuel ratios. The moderator to fuel ratio for the maximum material buckling for the particular system is selected automatically and the corresponding material buckling is calculated. 2 - Method of solution: The method used is an analytical solution of the one-group diffusion equations with various corrections and approximations. 3 - Restrictions on the complexity of the problem: Up to 32 different materials in the fuel element may be used

Combustion and exhaust emission characteristics of a dual fuel compression ignition engine operated with pilot Diesel fuel and natural gas

International Nuclear Information System (INIS)

Papagiannakis, R.G.; Hountalas, D.T.

2004-01-01

Towards the effort of reducing pollutant emissions, especially soot and nitrogen oxides, from direct injection Diesel engines, engineers have proposed various solutions, one of which is the use of a gaseous fuel as a partial supplement for liquid Diesel fuel. These engines are known as dual fuel combustion engines, i.e. they use conventional Diesel fuel and a gaseous fuel as well. This technology is currently reintroduced, associated with efforts to overcome various difficulties of HCCI engines, using various fuels. The use of natural gas as an alternative fuel is a promising solution. The potential benefits of using natural gas in Diesel engines are both economical and environmental. The high autoignition temperature of natural gas is a serious advantage since the compression ratio of conventional Diesel engines can be maintained. The present contribution describes an experimental investigation conducted on a single cylinder DI Diesel engine, which has been properly modified to operate under dual fuel conditions. The primary amount of fuel is the gaseous one, which is ignited by a pilot Diesel liquid injection. Comparative results are given for various engine speeds and loads for conventional Diesel and dual fuel operation, revealing the effect of dual fuel combustion on engine performance and exhaust emissions

Fuel cells principles, design, and analysis

CERN Document Server

Revankar, Shripad T

2014-01-01

""This book covers all essential themes of fuel cells ranging from fundamentals to applications. It includes key advanced topics important for understanding correctly the underlying multi-science phenomena of fuel cell processes. The book does not only cope with traditional fuel cells but also discusses the future concepts of fuel cells. The book is rich on examples and solutions important for applying the theory into practical use.""-Peter Lund, Aalto University, Helsinki""A good introduction to the range of disciplines needed to design, build and test fuel cells.""-Nigel Brandon, Imperial Co

Radionuclide release from research reactor spent fuel

Energy Technology Data Exchange (ETDEWEB)

Curtius, H., E-mail: h.curtius@fz-juelich.de [Forschungszentrum Juelich, Institut fuer Energieforschung, IEF-6 Sicherheitsforschung und Reaktortechnik, Geb. 05.3, D-52425 Juelich (Germany); Kaiser, G.; Mueller, E.; Bosbach, D. [Forschungszentrum Juelich, Institut fuer Energieforschung, IEF-6 Sicherheitsforschung und Reaktortechnik, Geb. 05.3, D-52425 Juelich (Germany)

2011-09-01

Numerous investigations with respect to LWR fuel under non oxidizing repository relevant conditions were performed. The results obtained indicate slow corrosion rates for the UO{sub 2} fuel matrix. Special fuel-types (mostly dispersed fuels, high enriched in {sup 235}U, cladded with aluminium) are used in German research reactors, whereas in German nuclear power plants, UO{sub 2}-fuel (LWR fuel, enrichment in {sup 235}U up to 5%, zircaloy as cladding) is used. Irradiated research reactor fuels contribute less than 1% to the total waste volume. In Germany, the state is responsible for fuel operation and for fuel back-end options. The institute for energy research (IEF-6) at the Research Center Juelich performs investigation with irradiated research reactor spent fuels under repository relevant conditions. In the study, the corrosion of research reactor spent fuel has been investigated in MgCl{sub 2}-rich salt brine and the radionuclide release fractions have been determined. Leaching experiments in brine with two different research reactor fuel-types were performed in a hot cell facility in order to determine the corrosion behaviour and the radionuclide release fractions. The corrosion of two dispersed research reactor fuel-types (UAl{sub x}-Al and U{sub 3}Si{sub 2}-Al) was studied in 400 mL MgCl{sub 2}-rich salt brine in the presence of Fe{sup 2+} under static and initially anoxic conditions. Within these experimental parameters, both fuel types corroded in the experimental time period of 3.5 years completely, and secondary alteration phases were formed. After complete corrosion of the used research reactor fuel samples, the inventories of Cs and Sr were quantitatively detected in solution. Solution concentrations of Am and Eu were lower than the solubility of Am(OH){sub 3}(s) and Eu(OH){sub 3}(s) solid phases respectively, and may be controlled by sorption processes. Pu concentrations may be controlled by Pu(IV) polymer species, but the presence of Pu(V) and Pu

Sustainable development - theory and practice of environmental consulting. Proceedings of a seminar of Zentrale Informationsstelle Umweltberatung Bayern. Vol. 11; Nachhaltige Entwicklung - Theorie und Praxis fuer die Umweltberatung. Seminarband der Zentralen Informationsstelle Umweltberatung Bayern. Bd. 11

Energy Technology Data Exchange (ETDEWEB)

Koller, U.; Behling, G.; Klemmer, A.; Haury, H.J. [comps.

1998-12-31

On 25/26 November, 1997, Zentrale Informationsstelle, Umweltberatung Bayern held its 11th seminar under the title ``Sustainable development - theory and practice of environmental consulting. Subjects related to the Agenda 21 were discussed in lectures and workshops. [Deutsch] Am 25. und 26. November 1997 veranstaltete die Zentrale Informationsstelle, Umweltberatung Bayern ihr elftes Seminar mit dem Thema ``Nachhaltige Entwicklung- Theorie und Praxis fuer die Umweltberatung``. In Fachvortraegen und Workshops wurden Themen zur Agenda 21 behandelt. (ABI)

Review: Gerd Jüttemann (Hrsg. (2013. Die Entwicklung der Psyche in der Geschichte der Menschheit

Directory of Open Access Journals (Sweden)

Uwe Krebs

2015-03-01

Full Text Available Der Vorbereitungsband für die Reihe "Die Psychogenese der Menschheit" – ein Sammelband aus 32 Beiträgen, betitelt "Die Entwicklung der Psyche in der Geschichte der Menschheit" und 2013 herausgegeben von Gerd JÜTTEMANN – wird in dieser Besprechung in mehreren Schritten vorgestellt und bewertet. Zunächst wird kontextuell argumentiert, dass die bewährte, empirisch-experimentelle Methodologie der Psychologie zur Vernachlässigung weiterer Erkenntnisverfahren führte, die bei Themen wie dem hier zu besprechenden Werk allein verbleiben und die kurz angesprochen werden. Sodann wird das Werk im Überblick knapp dargestellt und die außergewöhnliche Heterogenität in Inhalten und Methoden betont. Die Besprechung einzelner Beiträge, die nach dem Gesichtspunkt großer Unterschiedlichkeit ausgewählt wurden, schließt sich an. Die abschließende Gesamtbewertung betont den lückenhaften Forschungsstand, die Notwendigkeit der allein verbleibenden qualitativen Methodik mit ihren verschiedenen Möglichkeiten und nennt Desiderata künftigen Vorgehens für diesen thematisch und methodisch interessanten Auftakt-Band, der insbesondere durch Dichte und Verschiedenheit der Beiträge beeindruckt. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1502219

ENIAK. Development of a non-motor injector coking test facility for alternative fuels; ENIAK. Entwicklung eines nichtmotorischen Injektorverkokungspruefstands fuer alternative Kraftstoffe

Energy Technology Data Exchange (ETDEWEB)

Hoffmann, Hajo; Schloss, Heide vom; Yang, Zhi; Grote, Melanie [OWI Oel-Waerme-Institut GmbH, Aachen (Germany). Gruppe Anwendungstechnik

2013-10-01

Poor Biodiesel quality, contamination with copper and zinc as well as undesired reactions between (several) additives and biodiesel components are known causes for nozzle fouling. Therefore, among other things, all additives have to pass a no-harm test. The standard fouling tests are two engine tests: the XUD9-test (CEC F-23-01) and the DW-10-test (CEC DF 98-08). The XUD9 is a cost efficient, fast and proven testing method. It uses, however, an obsolete indirect injection diesel engine. The newer DW10 test is complex, costly and designed for high stress. This reduces the engine life and leads to a fuel consumption of approximately 1,000 l per test, both contributing to the high costs of the test. The main goal of the project ENIAK is the development, assembly, commissioning, and evaluation of a non-engine fuel injector test. It uses four complete common rail systems. The injection takes place in four self-designed reactors instead of an engine, and the fuel is not combusted, but re-condensed and pumped in a circle. If the test method proves to be as reliable as expected, it can be used as an alternative test method for injector fouling with low requirements regarding infrastructure on the testing site and sample volume. The project is funded by the the federal ministry of consumer protection, food and agriculture via FNR (''Fachagentur Nachwachsende Rohstoffe'', Agency for Renewable Resources). (orig.)

Agro-fuels: southern impacts

International Nuclear Information System (INIS)

Duterme, B.

2011-01-01

At a time of controversies about global warming, agro-fuels production is often presented as a future solution for automotive fuels and as a new way of development for southern countries. However, in Asia, South America and Africa, it very often takes the form of huge mono-culture areas of sugar cane, palm oil and soy bean in the hands of multinational companies of the agriculture and food industry. The consequences of these land, social and environmental impacts in Southern countries is an increase of disequilibria and a threat for the diet of local populations by changing the appropriation of lands. Deforestation, private monopolization of lands, concentration of profits, soils and water pollution, biodiversity impoverishment, exploitation of vulnerable manpower, populations migration, violation of human rights are today the consequences of mass production of agro-fuels in Southern countries. To what conditions a fair re-appropriation and a sustainable development of agro-fuels production and consumption is foreseeable? The solutions require a re-shaping of economical and agricultural politics. The book gathers testimonies and analyses from specialists who have evaluated locally the consequences of these energy choices. (J.S.)

Thermodynamic and kinetic modelling of fuel oxidation behaviour in operating defective fuel

International Nuclear Information System (INIS)

Lewis, B.J.; Thompson, W.T.; Akbari, F.; Thompson, D.M.; Thurgood, C.; Higgs, J.

2004-01-01

A theoretical treatment has been developed to predict the fuel oxidation behaviour in operating defective nuclear fuel elements. The equilibrium stoichiometry deviation in the hyper-stoichiometric fuel has been derived from thermodynamic considerations using a self-consistent set of thermodynamic properties for the U-O system, which emphasizes replication of solubilities and three-phase invariant conditions displayed in the U-O binary phase diagram. The kinetics model accounts for multi-phase transport including interstitial oxygen diffusion in the solid and gas-phase transport of hydrogen and steam in the fuel cracks. The fuel oxidation model is further coupled to a heat conduction model to account for the feedback effect of a reduced thermal conductivity in the hyper-stoichiometric fuel. A numerical solution has been developed using a finite-element technique with the FEMLAB software package. The model has been compared to available data from several in-reactor X-2 loop experiments with defective fuel conducted at the Chalk River Laboratories. The model has also been benchmarked against an O/U profile measurement for a spent defective fuel element discharged from a commercial reactor

Water reactive hydrogen fuel cell power system

Science.gov (United States)

Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

2014-01-21

A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into a fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

Small-scale reforming of diesel and jet fuels to make hydrogen and syngas for fuel cells: A review

International Nuclear Information System (INIS)

Xu, Xinhai; Li, Peiwen; Shen, Yuesong

2013-01-01

Highlights: • Issues of reforming of heavy hydrocarbon fuels are reviewed. • The advantages of autothermal reforming over other types of reforming are discussed. • The causes and solutions of the major problems for reforming reactors are studied. • Designs and startup strategies for autothermal reforming reactors are proposed. - Abstract: This paper reviews the technological features and challenges of autothermal reforming (ATR) of heavy hydrocarbon fuels for producing hydrogen and syngas onboard to supply fuels to fuel cells for auxiliary power units. A brief introduction at the beginning enumerates the advantages of using heavy hydrocarbon fuels onboard to provide hydrogen or syngas for fuel cells such as solid oxide fuel cells (SOFCs). A detailed review of the reforming and processing technologies of diesel and jet fuels is then presented. The advantages of ATR over steam reforming (SR) and partial oxidation reforming (POX) are summarized, and the ATR reaction is analyzed from a thermodynamic point of view. The causes and possible solutions to the major problems existing in ATR reactors, including hot spots, formation of coke, and inhomogeneous mixing of fuel, steam, and air, are reviewed and studied. Designs of ATR reactors are discussed, and three different reactors, one with a fixed bed, one with monoliths, and one with microchannels are investigated. Novel ideas for design and startup strategies for ATR reactors are proposed at the end of the review

Improvement of fuel sampling device for STACY and TRACY

International Nuclear Information System (INIS)

Hirose, Hideyuki; Sakuraba, Koichi; Onodera, Seiji

1998-05-01

STACY and TRACY, static and transient experiment facilities in NUCEF, use solution fuel. It is important to analyze accurately fuel composition (uranium enrichment, uranium concentration, nitric acid morality, amount of impurities, radioactivity of FP) for their safety operation and improvement of experimental accuracy. Both STACY and TRACY have the sampling devices to sample fuel solution for that purpose. The previous sampling devices of STACY and TRACY had been designed to dilute fuel sample with nitric acid. Its sampling mechanism could pour fuel sample into sampling vessel by a piston drive of nitric acid in the burette. It was, however, sometimes found that sample fuel solution was diluted by mixing with nitric acid in the burette. Therefore, the sampling mechanism was change into a fixed quantity pump drive which didn't use nitric acid. The authors confirmed that the performance of the new sampling device was improved by changing sampling mechanism. It was confirmed through the function test that the uncertainty in uranium concentration measurement using the improved sampling device was 0.14%, and less than the designed value of 0.2% (coefficient of variation). (author)

Government--utility interaction on spent fuel disposition

International Nuclear Information System (INIS)

Mills, L.E.

1978-01-01

The question of the needs of the electrical power industry for spent fuel storage in light of the moratorium on fuel reprocessing is addressed. The author feels that since the Federal government has assumed the responsibility for spent fuel storage, it is imperative that a firm plan, program, legislation, and funding be forthcoming immediately. Designation of an existing government site with existing nuclear activities in order to expedite the establishment of a storage facility is recommended. It is felt that the timing for such a site should be ''at the earliest possible date.'' Without storage facilities being provided by the government, utilities will be forced to build storage facilities at the reactor sites. This course of action is not considered cost effective but certainly preferable to shutting down the reactors. It is emphasized that spent fuel storage must be an interim solution and certainly not a final solution to the fuel reprocessing and waste disposal aspects of nuclear technology

Modeling the highway transportation of spent fuel

International Nuclear Information System (INIS)

Harrison, I.G.

1986-01-01

There will be a substantial increase in the number of spent fuel shipments on the nation's highway system in the next thirty years. Most of the spent fuel will be moving from reactors to a spent fuel repository. This study develops two models that evaluate the risk and cost of moving the spent fuel. The Minimum Total Transport Risk Model (MTTRM) seeks an efficient solution for this problem by finding the minimum risk path through the network and sending all the spent fuel shipments over this one path. The Equilibrium Transport Risk Model (ETRM) finds an equitable solution by distributing the shipments over a number of paths in the network. This model decreases the risk along individual paths, but increases society's risk because the spent fuel shipments are traveling over more links in the network. The study finds that there is a trade off between path risk and societal risk. As path risk declines, societal risk rises. The cost of shipping also increases as the number of paths expand. The cost and risk of shipping spent fuel from ten reactors to four potential repository sites are evaluated using the MTTRM. The temporary monitored retrievable storage (MRS) facility in Tennessee is found to be the minimum cost and minimum risk solution. When direct shipment to the permanent sites is considered, Deaf Smith, Texas is the least cost and least incident free transport risk location. Yucca Mountain, Nevada is the least risk location when the focus is placed on the potential consequences of an accident

A conceptual model for the fuel oxidation of defective fuel

International Nuclear Information System (INIS)

Higgs, J.D.; Lewis, B.J.; Thompson, W.T.; He, Z.

2007-01-01

A mechanistic conceptual model has been developed to predict the fuel oxidation behaviour in operating defective fuel elements for water-cooled nuclear reactors. This theoretical work accounts for gas-phase transport and sheath reactions in the fuel-to-sheath gap to determine the local oxygen potential. An improved thermodynamic analysis has also been incorporated into the model to describe the equilibrium state of the oxidized fuel. The fuel oxidation kinetics treatment accounts for multi-phase transport including normal diffusion and thermodiffusion for interstitial oxygen migration in the solid, as well as gas-phase transport in the fuel pellet cracks. The fuel oxidation treatment is further coupled to a heat conduction equation. A numerical solution of the coupled transport equations is obtained by a finite-element technique with the FEMLAB 3.1 software package. The model is able to provide radial-axial profiles of the oxygen-to-uranium ratio and the fuel temperatures as a function of time in the defective element for a wide range of element powers and defect sizes. The model results are assessed against coulometric titration measurements of the oxygen-to-metal profile for pellet samples taken from ten spent defective elements discharged from the National Research Universal Reactor at the Chalk River Laboratories and commercial reactors

DANCOFF-3, Dancoff Correction for Cylindrical Fuel Rod at H2O Gaps and for Fuel Clusters

International Nuclear Information System (INIS)

Sauer, A.

1989-01-01

1 - Nature of physical problem solved: Calculation of the Dancoff correction for cylindrical fuel rods in square and hexagonal infinite lattices, for fuel element rods near water gaps, and for fuel rod clusters. 2 - Method of solution: Evaluation by direct numerical integration over the moderator region. 3 - Restrictions on the complexity of the problem: For every rod arrangement at most 100 cases with different materials cross- sections

Fuel flexibility in power generation onboard offshore floating units

Energy Technology Data Exchange (ETDEWEB)

Keep, Jeroen van [Waertsilae Corporation, Helsinki (Finland)

2012-07-01

Power Plants for offshore oil and gas installations utilizing dual fuel (DF) reciprocating engines are by many owners seen as an interesting alternative to conventional solutions due to the apparent advantages in fuel flexibility, fuel efficiency and lower emission. The paper summarizes the dual fuel technology, typical solutions for FPSO's and operational. Items that are discussed: DF operation and how it works; fuel flexibility, including transfer between fuel modes; fuel efficiency, also in production an important cost saver; emissions of the different fuel modes; size and weights, constraints; experiences of the P-63 project. With the above it is safe to conclude that the DF-technology is mature with important benefits for the offshore production market in certain specific applications, most notably the FPSO's for fields in low gas to oil ratios, bringing important fuel cost savings and also for new-built F-LNG/FSO/FPSO's where the power plant can be accommodated below decks, freeing up valuable deck space for the process plant. (author)

Validation of MCNP: SPERT-D and BORAX-V fuel

International Nuclear Information System (INIS)

Crawford, C.; Palmer, B.

1992-11-01

This report discusses critical experiments involving SPERT-D 1,2 fuel elements and BORAX-V 3-8 fuel which have been modeled and calculations performed with MCNP. MCNP is a Monte Carlo based transport code. For this study continuous-energy nuclear data from the ENDF/B-V cross section library was used. The SPERT-D experiments consisted of various arrays of fuel elements moderated and reflected with either water or a uranyl nitrate solution. Some SPERT-D experiments used cadmium as a fixed neutron poison, while others were poisoned with various concentrations of boron in the moderating/reflecting solution. ne BORAX-V experiments were arrays of either boiling fuel rod assemblies or superheater assemblies, both types of arrays were moderated and reflected with water. In one boiling fuel experiment, two fuel rods were replaced with borated stainless steel poison rods

Temperature Profile of the Solution Vessel of an Accelerator-Driven Subcritical Fissile Solution System

Energy Technology Data Exchange (ETDEWEB)

Klein, Steven Karl [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Determan, John C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2015-09-14

Dynamic System Simulation (DSS) models of fissile solution systems have been developed and verified against a variety of historical configurations. DSS techniques have been applied specifically to subcritical accelerator-driven systems using fissile solution fuels of uranium. Initial DSS models were developed in DESIRE, a specialized simulation scripting language. In order to tailor the DSS models to specifically meet needs of system designers they were converted to a Visual Studio implementation, and one of these subsequently to National Instrument’s LabVIEW for human factors engineering and operator training. Specific operational characteristics of subcritical accelerator-driven systems have been examined using a DSS model tailored to this particular class using fissile fuel.

Temperature Profile of the Solution Vessel of an Accelerator-Driven Subcritical Fissile Solution System

International Nuclear Information System (INIS)

Klein, Steven Karl; Determan, John C.

2015-01-01

Dynamic System Simulation (DSS) models of fissile solution systems have been developed and verified against a variety of historical configurations. DSS techniques have been applied specifically to subcritical accelerator-driven systems using fissile solution fuels of uranium. Initial DSS models were developed in DESIRE, a specialized simulation scripting language. In order to tailor the DSS models to specifically meet needs of system designers they were converted to a Visual Studio implementation, and one of these subsequently to National Instrument's LabVIEW for human factors engineering and operator training. Specific operational characteristics of subcritical accelerator-driven systems have been examined using a DSS model tailored to this particular class using fissile fuel.

Experimental determination and chemical modelling of radiolytic processes at the spent fuel/water interface. Experiments carried out in carbonate solutions in absence and presence of chloride

Energy Technology Data Exchange (ETDEWEB)

Bruno, Jordi; Cera, Esther; Grive, Mireia; Duro, Lara [Enviros Spain SL (Spain); Eriksen, Trygve [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Nuclear Chemistry

2003-01-01

We report on the recent experimental and modelling results of a research programme that started in 1995. The aim has been to understand the kinetic and thermodynamic processes that control the radiolytic generation of oxidants and reductants at the spent fuel water interface and their consequences for spent fuel matrix stability and radionuclide release. This has been done by carrying out well-controlled dissolution experiments of PWR Ringhals spent fuel fragments in an initially anoxic closed system and by using different solution compositions. Experimental series started with several tests carried out with deionised water as solvent, in a second phase experiments were conducted with 10 mM bicarbonate solutions. New experimental series were set up during the last two years by using the same bicarbonate content in solutions with varying NaCl concentrations in order to ascertain the role of this ligand on the radiolytic products and its consequence for radionuclide release. The selected NaCl concentrations are in the range of 0.1 to 10 mM. Experimental data shows that uranium dissolution at early contact times is controlled by the oxidation of the UO{sub 2} matrix. This process controls the co-dissolution of most of the analysed radionuclides, including Sr, Mo, Tc, Np and surprisingly enough, Cs. In the overall the release rates for U and the matrix associated radionuclides are in the range of 10{sup -6} moles/day with a clear decreasing trend with exposure time and after 2 years the initial release rates have decreased down to 3x10{sup -8} moles/day. The solubility of the released actinides appears to be limited by the formation of An(IV) hydroxide phases, although Np concentrations in solution did not reach solubility levels during the time intervals of the present tests. No secondary solid phase appears to control the solubility of the rest of the elements.

Renewable energies in Germany. Data on the development in 2016; Erneuerbare Energien in Deutschland. Daten zur Entwicklung im Jahr 2016

Energy Technology Data Exchange (ETDEWEB)

NONE

2017-03-15

The Working Group on Renewable Energy Statistics (AGEE-Stat), which regularly evaluates the use of renewable energies on behalf of the German Federal Ministry of Economics and Energy, has made an initial assessment of the development of renewable energies in Germany on the basis of available, mostly provisional data of 2016. The present background paper describes the previous findings for the areas of electricity, heat and transport, supplemented by figures on economic significance as well as on emission reductions through renewable energies. [German] Die Arbeitsgruppe Erneuerbare Energien-Statistik (AGEE-Stat), die im Auftrag des Bundesministeriums fuer Wirtschaft und Energie regelmaessig die Nutzung der erneuerbaren Energien bilanziert, hat auf der Grundlage verfuegbarer, zumeist vorlaeufiger Daten eine erste Abschaetzung zur Entwicklung der erneuerbaren Energien in Deutschland im Jahr 2016 erstellt. Das vorliegende Hintergrundpapier beschreibt die bisherigen Erkenntnisse fuer die Bereiche Strom, Waerme und Verkehr, ergaenzt um Zahlen zur wirtschaftlichen Bedeutung sowie zur Emissionsvermeidung durch erneuerbare Energien.

Theory of precipitation effects on dead cylindrical fuels

Science.gov (United States)

Michael A. Fosberg

1972-01-01

Numerical and analytical solutions of the Fickian diffusion equation were used to determine the effects of precipitation on dead cylindrical forest fuels. The analytical solution provided a physical framework. The numerical solutions were then used to refine the analytical solution through a similarity argument. The theoretical solutions predicted realistic rates of...

Choosing a spent fuel interim storage system

International Nuclear Information System (INIS)

Roland, V.; Hunter, I.

2001-01-01

The Transnucleaire Group has developed different modular solutions to address spent fuel interim storage needs of NPP. These solutions, that are present in Europe, USA and Asia are metal casks (dual purpose or storage only) of the TN 24 family and the NUHOMS canister based system. It is not always simple for an operator to sort out relevant choice criteria. After explaining the basic designs involved on the examples of the TN 120 WWER dual purpose cask and the NUHOMS 56 WWER for WWER 440 spent fuel, we shall discuss the criteria that govern the choice of a given spent fuel interim storage system from the stand point of the operator. In conclusion, choosing and implementing an interim storage system is a complex process, whose implications can be far reaching for the long-term success of a spent fuel management policy. (author)

Particle Count Limits Recommendation for Aviation Fuel

Science.gov (United States)

2015-10-05

Particle Counter Methodology • Particle counts are taken utilizing calibration methodologies and standardized cleanliness code ratings – ISO 11171 – ISO...Limits Receipt Vehicle Fuel Tank Fuel Injector Aviation Fuel DEF (AUST) 5695B 18/16/13 Parker 18/16/13 14/10/7 Pamas / Parker / Particle Solutions 19/17...12 U.S. DOD 19/17/14/13* Diesel Fuel World Wide Fuel Charter 5th 18/16/13 DEF (AUST) 5695B 18/16/13 Caterpillar 18/16/13 Detroit Diesel 18/16/13 MTU

Solution of the two dimensional diffusion and transport equations in a rectangular lattice with an elliptical fuel element using Fourier transform methods: One and two group cases

International Nuclear Information System (INIS)

Williams, M.M.R.; Hall, S.K.; Eaton, M.D.

2014-01-01

Highlights: • A rectangular reactor cell with an elliptical fuel element. • Solution of transport and diffusion equations by Fourier expansion. • Numerical examples showing convergence. • Two group cell problems. - Abstract: A method for solving the diffusion and transport equations in a rectangular lattice cell with an elliptical fuel element has been developed using a Fourier expansion of the neutron flux. The method is applied to a one group model with a source in the moderator. The cell flux is obtained and also the associated disadvantage factor. In addition to the one speed case, we also consider the two group equations in the cell which now become an eigenvalue problem for the lattice multiplication factor. The method of solution relies upon an efficient procedure to solve a large set of simultaneous linear equations and for this we use the IMSL library routines. Our method is compared with the results from a finite element code. The main drawback of the problem arises from the very large number of terms required in the Fourier series which taxes the storage and speed of the computer. Nevertheless, useful solutions are obtained in geometries that would normally require the use of finite element or analogous methods, for this reason the Fourier method is useful for comparison with that type of numerical approach. Extension of the method to more intricate fuel shapes, such as stars and cruciforms as well as superpositions of these, is possible

Nuclear fuel

Energy Technology Data Exchange (ETDEWEB)

Nakano, H [Power Reactor and Nuclear Fuel Development Corp., Tokyo (Japan)

1976-10-01

It is expected that nuclear power generation will reach 49 million kW in 1985 and 129 million kW in 1995, and the nuclear fuel having to be supplied and processed will increase in proportion to these values. The technical problems concerning nuclear fuel are presented on the basis of the balance between the benefit for human beings and the burden on the human beings. Recently, especially the downstream of nuclear fuel attracts public attention. Enriched uranium as the raw material for light water reactor fuel is almost monopolized by the U.S., and the technical information has not been published for fear of the diversion to nuclear weapons. In this paper, the present situations of uranium enrichment, fuel fabrication, transportation, reprocessing and waste disposal and the future problems are described according to the path of nuclear fuel cycle. The demand and supply of enriched uranium in Japan will be balanced up to about 1988, but afterwards, the supply must rely upon the early establishment of the domestic technology by centrifugal separation method. No problem remains in the fabrication of light water reactor fuel, but for the fabrication of mixed oxide fuel, the mechanization of the production facility and labor saving are necessary. The solution of the capital risk for the construction of the second reprocessing plant is the main problem. Japan must develop waste disposal techniques with all-out efforts.

Polyvalent fuel treatment facility (TCP): shearing and dissolution of used fuel at La Hague facility

Energy Technology Data Exchange (ETDEWEB)

Brueziere, J.; Tribout-Maurizi, A.; Durand, L.; Bertrand, N. [Recycling Business Unit, AREVA, 1 place de la coupole, 92084 Paris La defense Cedex (France)

2013-07-01

Although many used nuclear fuel types have already been recycled, recycling plants are generally optimized for Light Water Reactor (LWR) UO{sub x} fuel. Benefits of used fuel recycling are consequently restricted to those fuels, with only limited capacity for the others like LWR MOX, Fast Reactor (FR) MOX or Research and Test Reactor (RTR) fuel. In order to recycle diverse fuel types, an innovative and polyvalent shearing and dissolving cell is planned to be put in operation in about 10 years at AREVA's La Hague recycling plant. This installation, called TCP (French acronym for polyvalent fuel treatment) will benefit from AREVA's industrial feedback, while taking part in the next steps towards a fast reactor fuel cycle development using innovative treatment solutions. Feasibility studies and R/Development trials on dissolution and shearing are currently ongoing. This new installation will allow AREVA to propose new services to its customers, in particular in term of MOX fuel, Research Test Reactors fuel and Fast Reactor fuel treatment. (authors)

Nuclear fuel element

International Nuclear Information System (INIS)

Iwano, Yoshihiko.

1993-01-01

Microfine cracks having a depth of less than 10% of a pipe thickness are disposed radially from a central axis each at an interval of less than 100 micron over the entire inner circumferential surface of a zirconium alloy fuel cladding tube. For manufacturing such a nuclear fuel element, the inside of the cladding tube is at first filled with an electrolyte solution of potassium chloride. Then, electrolysis is conducted using the cladding tube as an anode and the electrolyte solution as a cathode, and the inner surface of the cladding tube with a zirconium dioxide layer having a predetermined thickness. Subsequently, the cladding tube is laid on a smooth steel plate and lightly compressed by other smooth steel plate to form microfine cracks in the zirconium dioxide layer on the inner surface of the cladding tube. Such a compressing operation is continuously applied to the cladding tube while rotating the cladding tube. This can inhibit progress of cracks on the inner surface of the cladding tube, thereby enabling to prevent failure of the cladding tube even if a pellet/cladding tube mechanical interaction is applied. Accordingly, reliability of the nuclear fuel elements is improved. (I.N.)

Proton exchange membrane fuel cells modeling

CERN Document Server

Gao, Fengge; Miraoui, Abdellatif

2013-01-01

The fuel cell is a potential candidate for energy storage and conversion in our future energy mix. It is able to directly convert the chemical energy stored in fuel (e.g. hydrogen) into electricity, without undergoing different intermediary conversion steps. In the field of mobile and stationary applications, it is considered to be one of the future energy solutions.Among the different fuel cell types, the proton exchange membrane (PEM) fuel cell has shown great potential in mobile applications, due to its low operating temperature, solid-state electrolyte and compactness.This book pre

Education - path towards solution regarding disposal of spent nuclear fuel

International Nuclear Information System (INIS)

Klein, D.E.

1991-01-01

Education, not emotional reaction, is the path to take in the safe disposal of spent nuclear fuel. Education is needed at all levels: Elementary schools, secondary schools, two-year colleges, four-year colleges, graduate schools, and adult education. The Office of Civilian Radioactive Waste Management (OCRWM) should not be expected to tackle this problem alone. Assistance is needed from local communities, schools, and state and federal governments. However, OCRWM can lay the foundation for a comprehensive educational plan directed specifically at educating the public on the spent nuclear fuel issue and OCRWM can begin the implementation of this plan

BWR fuel cycle optimization using neural networks

International Nuclear Information System (INIS)

Ortiz-Servin, Juan Jose; Castillo, Jose Alejandro; Pelta, David Alejandro

2011-01-01

Highlights: → OCONN a new system to optimize all nuclear fuel management steps in a coupled way. → OCON is based on an artificial recurrent neural network to find the best combination of partial solutions to each fuel management step. → OCONN works with a fuel lattices' stock, a fuel reloads' stock and a control rod patterns' stock, previously obtained with different heuristic techniques. → Results show OCONN is able to find good combinations according the global objective function. - Abstract: In nuclear fuel management activities for BWRs, four combinatorial optimization problems are solved: fuel lattice design, axial fuel bundle design, fuel reload design and control rod patterns design. Traditionally, these problems have been solved in separated ways due to their complexity and the required computational resources. In the specialized literature there are some attempts to solve fuel reloads and control rod patterns design or fuel lattice and axial fuel bundle design in a coupled way. In this paper, the system OCONN to solve all of these problems in a coupled way is shown. This system is based on an artificial recurrent neural network to find the best combination of partial solutions to each problem, in order to maximize a global objective function. The new system works with a fuel lattices' stock, a fuel reloads' stock and a control rod patterns' stock, previously obtained with different heuristic techniques. The system was tested to design an equilibrium cycle with a cycle length of 18 months. Results show that the new system is able to find good combinations. Cycle length is reached and safety parameters are fulfilled.

Fuel fabrication and post-irradiation examination

Energy Technology Data Exchange (ETDEWEB)

Venter, P J; Aspeling, J C [Atomic Energy Corporation of South Africa Ltd., Pretoria (South Africa)

1990-06-01

This paper provides an overview of the A/c's Bevan and Eldopar facilities for the fabrication of nuclear fuel. It also describes the sophisticated Hot Cell Complex, which is capable of accommodating pressurised water reactor fuel and various other irradiated samples. Some interesting problems and their solutions are discussed. (author)

Fuel fabrication and post-irradiation examination

International Nuclear Information System (INIS)

Venter, P.J.; Aspeling, J.C.

1990-01-01

This paper provides an overview of the A/c's Bevan and Eldopar facilities for the fabrication of nuclear fuel. It also describes the sophisticated Hot Cell Complex, which is capable of accommodating pressurised water reactor fuel and various other irradiated samples. Some interesting problems and their solutions are discussed. (author)

Electrocoagulation of solvent residues in the reprocessing of spent nuclear fuels

International Nuclear Information System (INIS)

Gidarakos, E.; Gramatte, W.; Koehling, A.; Schmitt, R.E.

1989-03-01

The aim of this project was to find out the potential of the method for the electrocoagulation (EC) of colloidally dispersed particles for an improved fine feed purification in the reprocessing of high burnup nuclear fuels with the help of real fuel solutions on a laboratory scale. In EC, the particles colloidally dispersed in the solution are fed with electric charges at the electrodes; this leads to a coagulation of the particles, with separation taking place at the electrodes. The methods of analysis chosen for the EC were nephelometry for inactive experiments with RuO 2 suspensions, and gamma spectroscopy for experiments with radioactive fuel solutions, with the nuclide pair Ru/Rh-106 acting as a colloidal tracer nuclide. On the whole, the present experimental data permit the conclusion that under the experimental conditions and with the apparatus applied, EC gives rise to the separation of colloidally dispersed noble metal particles in an active fuel solution. (orig./RB) [de

A technical solution to a difficult problem - An update

International Nuclear Information System (INIS)

Asselstine, J.K.

1985-01-01

A goal of the Reduced Enrichment Research and Test Reactor Program (RERTR) established by the U.S. Department of Energy is to develop the technical means needed to utilize LEU instead of HEU fuels in research and test reactors and to do so without operational penalties and without affecting safety characteristics. This goal has been pursued now for seven years in cooperation with many of you who are participants in this conference. The program has made significant progress in the development, demonstration and application of new LEU research reactor fuels. According to recent projections, the percentage of HEU fuel in international commerce which is technically replaceable with LEU fuels has been growing steadily as research continues. There appears to be no technical barrier to eventual replacement of HEU fuel with LEU fuel in research and test reactors. While there are many politically complex and technically difficult issues involved in nonproliferation, I conclude that the use of highly enriched weapons grade uranium as a fuel in civilian research reactors stands out as one problem which has a straight forward technical solution. The technical solution is the effort you in the RERTR program are embarked on. Once that solution is in hand, the operators of research reactors are urged to take political and legal initiatives to make the conversion happen. By effecting this conversion they will help minimize the trade in highly enriched uranium and make the world a little safer

A technical solution to a difficult problem - An update

Energy Technology Data Exchange (ETDEWEB)

Asselstine, J K

1985-07-01

A goal of the Reduced Enrichment Research and Test Reactor Program (RERTR) established by the U.S. Department of Energy is to develop the technical means needed to utilize LEU instead of HEU fuels in research and test reactors and to do so without operational penalties and without affecting safety characteristics. This goal has been pursued now for seven years in cooperation with many of you who are participants in this conference. The program has made significant progress in the development, demonstration and application of new LEU research reactor fuels. According to recent projections, the percentage of HEU fuel in international commerce which is technically replaceable with LEU fuels has been growing steadily as research continues. There appears to be no technical barrier to eventual replacement of HEU fuel with LEU fuel in research and test reactors. While there are many politically complex and technically difficult issues involved in nonproliferation, I conclude that the use of highly enriched weapons grade uranium as a fuel in civilian research reactors stands out as one problem which has a straight forward technical solution. The technical solution is the effort you in the RERTR program are embarked on. Once that solution is in hand, the operators of research reactors are urged to take political and legal initiatives to make the conversion happen. By effecting this conversion they will help minimize the trade in highly enriched uranium and make the world a little safer.

Closing the fuel cycle

International Nuclear Information System (INIS)

Aycoberry, C.; Rougeau, J.P.

1987-01-01

The progressive implementation of some key nuclear fuel cycle capecities in a country corresponds to a strategy for the acquisition of an independant energy source, France, Japan, and some European countries are engaged in such strategic programs. In France, COGEMA, the nuclear fuel company, has now completed the industrial demonstration of the closed fuel cycle. Its experience covers every step of the front-end and of the back-end: transportation of spent fuels, storage, reprocessing, wastes conditioning. The La Hague reprocessing plant smooth operation, as well as the large investment program under active progress can testify of full mastering of this industry. Together with other French and European companies, COGEMA is engaged in the recycling industry, both for uranium through conversion of uranyl nitrate for its further reeichment, and for plutonium through MOX fuel fabrication. Reprocessing and recycling offer the optimum solution for a complete, economic, safe and future-oriented fuel cycle, hence contributing to the necessary development of nuclear energy. (author)

Nuclear fuel cycle: (5) reprocessing of irradiated fuel

Energy Technology Data Exchange (ETDEWEB)

Williams, J.A.

1977-09-01

The evolution of the reprocessing of irradiated fuel and the recovery of plutonium from it is traced out, starting by following the Manhatten project up to the present time. A brief description of the plant and processes used for reprocessing is given, while the Purex process, which is used in all plants today, is given special attention. Some of the important safety problems of reprocessing plants are considered, together with the solutions which have been adopted. Some examples of the more important safety aspects are the control of activity, criticality control, and the environmental impact. The related topic of irradiated fuel transport is briefly discussed.

Trends in the specific carbon dioxide emissions of the german fuel mix; Entwicklung der spezifischen Kohlendioxid-Emissionen des deutschen Strommix

Energy Technology Data Exchange (ETDEWEB)

Machat, Marcus; Werner, Kathrin

2007-04-15

The specific emission factor of the German fuel mix is calculated from the direct CO2 emissions of electric power generation and from the net electric power available for end use consumption. The emission factor was reduced between 1990 and 2005, owing to higher efficiencies of modernized power plants and to a bigger share of renewable energy sources. The brochure, published by the Federal Environmental Office, presents trends and diagrams.

Premises and solutions regarding a global approach of gaseous pollutants emissions from the fossil fuel power plants in Romania

International Nuclear Information System (INIS)

Tutuianu, O.; Fulger, E.D.; Vieru, A.; Feher, M.

1996-01-01

This paper deals with the present state of RENEL (Romanian Electricity Authority) - controlled thermal power plants from the point of view of technical aspects, utilized fuels and pollutant emissions. National and international regulations are also analyzed as well as their implications concerning the management of pollutant atmospheric emissions of the plants of RENEL. Starting from these premises the paper points out the advantage of global approach of pollution problems and offers solutions already implemented by RENEL. This global approach will result in an optimization of costs implied in pollutant emission limitations as the most efficient solution were found and applied. Having in view this treatment of the pollution problems, RENEL has submitted to the Ministry of the Industries and to the Ministry of Waters, Forests and Environmental Protection a 'Convention on the limitation of CO 2 , SO 2 and NO x emissions produced in the thermal power plants of RENEL'. (author)

Innovative automation solutions applied to nuclear fuel production and inspection processes

International Nuclear Information System (INIS)

Vas, Ananth

2012-01-01

The nuclear industry in India is slated for fast paced growth in the coming years, with a great focus on increasing the capacity for producing, inspecting and finally reprocessing of nuclear fuel. Modern techniques of industrial automation such as robotics, machine vision and laser based systems have been deployed extensively to improve the productivity and output of existing and future installations, particularly for the fuel handling stages mentioned

Analytical solution of the energy management for fuel cell hybrid propulsion systems

NARCIS (Netherlands)

P.P.J. van den Bosch; E. Tazelaar; Bram Veenhuizen

2012-01-01

The objective of an energy management strategy for fuel cell hybrid propulsion systems is to minimize the fuel needed to provide the required power demand. This minimization is defined as an optimization problem. Methods such as dynamic programming numerically solve this optimization problem.

Solvent wash solution

International Nuclear Information System (INIS)

Neace, J.C.

1986-01-01

This patent describes a process for removing diluent degradation products from a solvent extraction solution comprising an admixture of an organic extractant for uranium and plutonium and a non-polar organic liquid diluent, which has been used to recover uranium and plutonium from spent nuclear fuel. Comprising combining a wash solution consisting of: (a) water; and (b) a positive amount up to about, an including, 50 volume percent of at least one highly-polar water-miscible organic solvent, based on the total volume of the water and the highly-polar organic solvent, with the solvent extraction solution after uranium and plutonium values have been stripped from the solvent extraction solution, the diluent degradation products dissolving in the highly-polar organic solvent and the extractant and diluent of the extraction solution not dissolving in the highly-polar organic solvent, and separating the highly-polar organic solvent and the extraction solution to obtain a purified extraction solution

Quality evaluation of the nuclear fuel manufactured in Romania before 1990

International Nuclear Information System (INIS)

Budan, O.; Galeriu, C.A.; Pascu, A.; Bailescu, A.; Andrei, G.

1997-01-01

Nuclear fuel fabricated in Romania before June 1990 was stored and was not licensed for the use in reactor. A preliminary appraisal performed by AECL and Zircatec experts in 1990, considered this fuel as being of suspect quality. Taking into consideration that Nuclear Fuel Plant was qualified to produce CANDU-6 fuel, only after 1990, RENEL-GEN authorized FCN to evaluate the actual quality of the stock fuel, in 1996. A documented evaluation program was developed and implemented. Stock production of each year was considered as one fuel bundle lot. Quality verification was done on statistical basis. Random sampling was applied, with the condition that each production week was represented in the sample. The results show that the fuel quality is not acceptable for in-reactor use. Recovery solutions for the stock fuel were established and already applied. An independent review of the program, results and recovery solutions, made by AECL confirmed the consistency of the work performed by FCN for stock fuel quality evaluation. (author)

Characterization of Ni-YSZ anodes for solid oxide fuel cells fabricated by solution precursor plasma spraying with axial feedstock injection

Science.gov (United States)

Metcalfe, Craig; Lay-Grindler, Elisa; Kesler, Olivera

2014-02-01

Nickel and yttria-stabilized zirconia (YSZ) anodes were fabricated by solution precursor plasma spraying (SPPS) and incorporated into metal-supported solid oxide fuel cells (SOFC). A power density of 0.45 W cm-2 at 0.7 V and a peak power density of 0.52 W cm-2 at 750 °C in humidified H2 was obtained, which are the first performance results reported for an SOFC having an anode fabricated by SPPS. The effects of solution composition, plasma gas composition, and stand-off distance on the composition of the deposited Ni-YSZ coatings by SPPS were evaluated. It was found that the addition of citric acid to the aqueous solution delayed re-solidification of NiO particles, improving the deposition efficiency and coating adhesion. The composition of the deposited coatings was found to vary with torch power. Increasing torch power led to coatings with decreasing Ni content, as a result of Ni vaporizing in-flight at stand-off distances less than 60 mm from the torch nozzle exit.

Natural gas: Fuel for urban fleets

International Nuclear Information System (INIS)

Mariani, F.

1992-01-01

The search for new ecological solutions for public transport has given an important role to natural gas for vehicles in the national context. Under current prices of fuel and costs of plants, the management of a bus fleet running on natural gas allows consistent savings, besides reducing the atmospheric pollution of urban centres. Within this context, solutions offered by current technology available on the market are examined. Low polluting emissions are taken into consideration and a complete analysis of costs and savings is reported. Reference is made to the Thermie European programme which calls for fuel diversification, energy conservation and air pollution abatement

Porous silicon-based direct hydrogen sulphide fuel cells.

Science.gov (United States)

Dzhafarov, T D; Yuksel, S Aydin

2011-10-01

In this paper, the use of Au/porous silicon/Silicon Schottky type structure, as a direct hydrogen sulphide fuel cell is demonstrated. The porous silicon filled with hydrochlorid acid was developed as a proton conduction membrane. The Au/Porous Silicon/Silicon cells were fabricated by first creating the porous silicon layer in single-crystalline Si using the anodic etching under illumination and then deposition Au catalyst layer onto the porous silicon. Using 80 mM H2S solution as fuel the open circuit voltage of 0.4 V was obtained and maximum power density of 30 W/m2 at room temperature was achieved. These results demonstrate that the Au/Porous Silicon/Silicon direct hydrogen sulphide fuel cell which uses H2S:dH2O solution as fuel and operates at room temperature can be considered as the most promising type of low cost fuel cell for small power-supply units.

The summary of WWER-1000 fuel utilization in Ukraine

Energy Technology Data Exchange (ETDEWEB)

Afanasyev, A [Ukrainian State Committee on Nuclear Power Utilization, Kiev (Ukraine)

1997-12-01

The report discusses the status of the fuel and fuel cycles of WWER-1000 reactors in Ukraine. The major reasons that caused the Ukrainian utilities to overcome the conservative design solutions in order to improve fuel utilization and extend fuel burnup are shown. At the same time the sufficient fuel reliability and fuel cycle flexibility are ensured. The burnup distribution in the unloaded fuel assemblies and average fuel rod failure rate are presented. The questions of reactor core operation safety and the economical problems of the front end of the fuel cycle are also considered. (author). 2 refs, 3 figs, 4 tabs.

Recovery of uranium from analytical waste solution

International Nuclear Information System (INIS)

Kumar, Pradeep; Anitha, M.; Singh, D.K.

2016-01-01

Dispersion fuels are considered as advance fuel for the nuclear reactor. Liquid waste containing significant quantity of uranium gets generated during chemical characterization of dispersion fuel. The present paper highlights the effort in devising a counter current solvent extraction process based on the synergistic mixture of D2EHPA and Cyanex 923 to recover uranium from such waste solutions. A typical analytical waste solution was found to have the following composition: U 3 O 8 (∼3 g/L), Al: 0.3 g/L, V: 15 ppm, Phosphoric acid: 3M, sulphuric acid : 1M and nitric acid : 1M. The aqueous solution is composed of mixture of either 3M phosphoric acid and 1M sulphuric acid or 1M sulphuric acid and 1M nitric acid, keeping metallic concentrations in the above mentioned range. Different organic solvents were tested. Based on the higher extraction of uranium with synergistic mixture of 0.5M D2EHPA + 0.125M Cyanex 923, it was selected for further investigation in the present work

A fuel-cell reactor for the direct synthesis of hydrogen peroxide alkaline solutions from H(2) and O(2).

Science.gov (United States)

Yamanaka, Ichiro; Onisawa, Takeshi; Hashimoto, Toshikazu; Murayama, Toru

2011-04-18

The effects of the type of fuel-cell reactors (undivided or divided by cation- and anion-exchange membranes), alkaline electrolytes (LiOH, NaOH, KOH), vapor-grown carbon fiber (VGCF) cathode components (additives: none, activated carbon, Valcan XC72, Black Pearls 2000, Seast-6, and Ketjen Black), and the flow rates of anolyte (0, 1.5, 12 mL h(-1)) and catholyte (0, 12 mL h(-1)) on the formation of hydrogen peroxide were studied. A divided fuel-cell system, O(2) (g)|VGCF-XC72 cathode|2 M NaOH catholyte|cation-exchange membrane (Nafion-117)|Pt/XC72-VGCF anode|2 M NaOH anolyte at 12 mL h(-1) flow|H(2) (g), was effective for the selective formation of hydrogen peroxide, with 130 mA cm(-2) , a 2 M aqueous solution of H(2)O(2)/NaOH, and a current efficiency of 95 % at atmospheric pressure and 298 K. The current and formation rate gradually decreased over a long period of time. The cause of the slow decrease in electrocatalytic performance was revealed and the decrease was stopped by a flow of catholyte. Cyclic voltammetry studies at the VGCF-XC72 electrode indicated that fast diffusion of O(2) from the gas phase to the electrode, and quick desorption of hydrogen peroxide from the electrode to the electrolyte were essential for the efficient formation of solutions of H(2)O(2)/NaOH. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Adsorption of mercury from aqueous solutions using palm oil fuel ash as an adsorbent - batch studies

Science.gov (United States)

Imla Syafiqah, M. S.; Yussof, H. W.

2018-03-01

Palm oil fuel ash (POFA) is one of the most abundantly produced waste materials. POFA is widely used by the oil palm industry which was collected as ash from the burning of empty fruit bunches fiber (EFB) and palm oil kernel shells (POKS) in the boiler as fuel to generate electricity. Mercury adsorption was conducted in a batch process to study the effects of contact time, initial Hg(II) ion concentration, and temperature. In this study, POFA was prepared and used for the removal of mercury(II) ion from the aqueous phase. The effects of various parameters such as contact time (0- 360 min), temperature (15 – 45 °C) and initial Hg(II) ion concentration (1 – 5 mg/L) for the removal of Hg(II) ion were studied in a batch process. The surface characterization was examined by scanning electron microscopy (SEM) and particle size distribution analysis. From this study, it was found that the highest Hg(II) ion removal was 99.60 % at pH 7, contact time of 4 h, initial Hg(II) ion concentration of 1 mg/L, adsorbent dosage 0.25 g and agitation speed of 100 rpm. The results implied that POFA has the potential as a low-cost and environmental friendly adsorbent for the removal of mercury from aqueous solution.

Microbial bio-fuels: a solution to carbon emissions and energy crisis.

Science.gov (United States)

Kumar, Arun; Kaushal, Sumit; Saraf, Shubhini A; Singh, Jay Shankar

2018-06-01

Increasing energy demand, limited fossil fuel resources and climate change have prompted development of alternative sustainable and economical fuel resources such as crop-based bio-ethanol and bio-diesel. However, there is concern over use of arable land that is used for food agriculture for creation of biofuel. Thus, there is a renewed interest in the use of microbes particularly microalgae for bio-fuel production. Microbes such as micro-algae and cyanobacteria that are used for biofuel production also produce other bioactive compounds under stressed conditions. Microbial agents used for biofuel production also produce bioactive compounds with antimicrobial, antiviral, anticoagulant, antioxidant, antifungal, anti-inflammatory and anticancer activity. Because of importance of such high-value compounds in aquaculture and bioremediation, and the potential to reduce carbon emissions and energy security, the biofuels produced by microbial biotechnology might substitute the crop-based bio-ethanol and bio-diesel production.

Heat transfer and temperature distribution in fuel

International Nuclear Information System (INIS)

Katanic-Popovic, J.; Stevanovic, M.

1966-01-01

This paper describes methods and procedures for determining the integral, mean and effective heat conductivity and temperature distribution in fuel, with the experimental solutions for measuring these parameters. A procedure for measuring the integral conductivity by measuring the power generated in the fuel is given [sr

Review on the effects of dual-fuel operation, using diesel and gaseous fuels, on emissions and performance

NARCIS (Netherlands)

Wagemakers, A.M.L.M.; Leermakers, C.A.J.

2012-01-01

In recent years the automotive industry has been forced to reduce the harmful and pollutant emissions emitted by direct injected diesel engines. To accomplish this difficult task various solutions have been proposed. One of these proposed solutions is the usage of gaseous fuels in addition to the

Hydrogen peroxide as sustainable fuel: electrocatalysts for production with a solar cell and decomposition with a fuel cell.

Science.gov (United States)

Yamada, Yusuke; Fukunishi, Yurie; Yamazaki, Shin-ichi; Fukuzumi, Shunichi

2010-10-21

Hydrogen peroxide was electrochemically produced by reducing oxygen in an aqueous solution with [Co(TCPP)] as a catalyst and photovoltaic solar cell operating at 0.5 V. Hydrogen peroxide thus produced is utilized as a fuel for a one-compartment fuel cell with Ag-Pb alloy nanoparticles as the cathode.

Demonstration of a SANEX Process in Centrifugal Contactors using the CyMe{sub 4}-BTBP Molecule on a Genuine Fuel Solution

Energy Technology Data Exchange (ETDEWEB)

Magnusson, D.; Christiansen, B.; Glatz, J.P.; Malmbeck, R.; Serrano-Purroy, D. [European Commiss, Joint Res Ctr, Inst Transuranium Elements, D-76125 Karlsruhe, (Germany); Foreman, M.R.S. [Univ Reading, Dept Chem, Reading RG6 6AD, Berks, (United Kingdom); Geist, A. [Forschungszentrum Karlsruhe, Inst Nukl Entsorgung, D-76021 Karlsruhe, (Germany); Modolo, G. [Forschungszentrum Julich, Inst Energy Res Safety Res and Reactor Technol, D-52425 Julich, (Germany); Sorel, C. [Commissariat Energie Atom Valrho, CEA, DRCP SCPS, F-30207 Bagnols Sur Ceze, (France)

2009-07-01

Efficient recovery of minor actinides from a genuine spent fuel solution has been successfully demonstrated by the CyMe{sub 4}-BTBP/DMDOHEMA extractant mixture dissolved in octanol. The continuous countercurrent process, in which actinides(III) were separated from lanthanides(III), was carried out in laboratory centrifugal contactors using an optimized flow-sheet involving a total of 16 stages. The process was divided into 9 stages for extraction from a 2 M nitric acid feed solution, 3 stages for lanthanide scrubbing, and 4 stages for actinide back-extraction. Excellent feed decontamination factors for Am (7000) and Cm (1000) were obtained and the recoveries of these elements were higher than 99.9%. More than 99.9% of the lanthanides were directed to the raffinate except Gd for which 0.32% was recovered in the product. (authors)

Advanced compressed hydrogen fuel storage systems

International Nuclear Information System (INIS)

Jeary, B.

2000-01-01

Dynetek was established in 1991 by a group of private investors, and since that time efforts have been focused on designing, improving, manufacturing and marketing advanced compressed fuel storage systems. The primary market for Dynetek fuel systems has been Natural Gas, however as the automotive industry investigates the possibility of using hydrogen as the fuel source solution in Alternative Energy Vehicles, there is a growing demand for hydrogen storage on -board. Dynetek is striving to meet the needs of the industry, by working towards developing a fuel storage system that will be efficient, economical, lightweight and eventually capable of storing enough hydrogen to match the driving range of the current gasoline fueled vehicles

Fuel consumption reduction in urban buses by using power split transmissions

International Nuclear Information System (INIS)

Macor, Alarico; Rossetti, Antonio

2013-01-01

Highlights: • Fuel consumption is highly influenced by transmission layout and control. • Continuous Variable Transmission allows control of the working point of the engine. • Hydromechanical CVT was numerically tested and compared with usual mechanical solutions. • CVT solution proved to reduce fuel consumption, improving the I.C.E. mean efficiency. • Results obtained from standard emission test cycles: New York and Manhattan Buses. - Abstract: The reduction of fuel consumption of urban vehicles is one of the challenges of the society today. Many promising technologies such as hybrid electric vehicles and fuel cells are the focus of a lot of research and investments, but high costs prevent their development on a large scale, especially in heavy duty vehicles. Simpler solutions, such as continuously variable transmissions, are then interesting alternatives: they preserve some of the advantages of hybrid solutions significantly reducing the overall cost of the system. Since these technologies allow the decoupling of the engine’s velocity from that of the wheels, optimised management of the engine becomes feasible, leading to lower fuel consumption than that of traditional solutions. This work compares the hydromechanical transmission with a traditional power shift in an application where efficiency and comfort are required: a city bus. The performance of a vehicle with a dual stage hydromechanical transmission has been investigated by means of a model implemented in the AMESim environment. A second model of a vehicle with a power shift transmission has been taken as reference solution. During the simulation of two standard test cycles, the first vehicle showed the lower fuel consumption, due to its better engine management, and to the operation of the torque converter during starts, which lowers the efficiency of the reference vehicle

Specific transport and storage solutions: Waste management facing current and future stakes of the nuclear fuel cycle

International Nuclear Information System (INIS)

Deniau, Helene; Gagner, Laurent; Gendreau, Francoise; Presta, Anne

2006-01-01

With major projects ongoing or being planned, and also with the daily management of radioactive waste from nuclear facilities, the role of transport and/or storage packaging has been often overlooked. Indeed, the packaging development process and transport solutions implemented are a key part of the waste management challenge: protection of people and environment. During over four decades, the AREVA Group has developed a complete and coherent system for the transport of waste produced by nuclear industries. The transport solutions integrate the factors to consider, as industrial transportation needs, various waste forms, associated hazards and current regulations. Thus, COGEMA LOGISTICS has designed, licensed and manufactured a large number of different transport, storage and dual purpose cask models for residues and all kinds of radioactive wastes. The present paper proposes to illustrate how a company acting both as a cask designer and a carrier is key to the waste management issue and how it can support the waste management policy of nuclear producers through their operational choices. We will focus on the COGEMA LOGISTICS technical solutions implemented to guarantee safe and secure transportation and storage solutions. We will describe different aspects of the cask design process, insisting on how it enables to fulfill both customer needs and regulation requirements. We will also mention the associated services developed by the AREVA Business Unit Logistics (COGEMA LOGISTICS, TRANSNUCLEAR, MAINCO, and LEMARECHAL CELESTIN) in order to manage transportation of liquid and solid waste towards interim or final storage sites. The paper has the following contents: About radioactive waste; - Radioactive waste classification; - High level activity waste and long-lived intermediate level waste; - Long-lived low level waste; - Short-lived low- and intermediate level waste; - Very low level waste; - The radioactive waste in nuclear fuel cycle; - Packaging design and

TEMP: a computer code to calculate fuel pin temperatures during a transient

International Nuclear Information System (INIS)

Bard, F.E.; Christensen, B.Y.; Gneiting, B.C.

1980-04-01

The computer code TEMP calculates fuel pin temperatures during a transient. It was developed to accommodate temperature calculations in any system of axi-symmetric concentric cylinders. When used to calculate fuel pin temperatures, the code will handle a fuel pin as simple as a solid cylinder or as complex as a central void surrounded by fuel that is broken into three regions by two circumferential cracks. Any fuel situation between these two extremes can be analyzed along with additional cladding, heat sink, coolant or capsule regions surrounding the fuel. The one-region version of the code accurately calculates the solution to two problems having closed-form solutions. The code uses an implicit method, an explicit method and a Crank-Nicolson (implicit-explicit) method

Gas-cooled Fast Reactor (GFR) fuel and In-Core Fuel Management

International Nuclear Information System (INIS)

Weaver, K.D.; Sterbentz, J.; Meyer, M.; Lowden, R.; Hoffman, E.; Wei, T.Y.C.

2004-01-01

The Gas-Cooled Fast Reactor (GCFR) has been chosen as one of six candidates for development as a Generation IV nuclear reactor based on: its ability to fully utilize fuel resources; minimize or reduce its own (and other systems) actinide inventory; produce high efficiency electricity; and the possibility to utilize high temperature process heat. Current design approaches include a high temperature (2 850 C) helium cooled reactor using a direct Brayton cycle, and a moderate temperature (550 C - 650 C) helium or supercritical carbon dioxide (S-CO 2 ) cooled reactor using direct or indirect Brayton cycles. These design choices have thermal efficiencies that approach 45% to 50%, and have turbomachinery sizes that are much more compact compared to steam plants. However, there are challenges associated with the GCFR, which are the focus of current research. This includes safety system design for decay heat removal, development of high temperature/high fluence fuels and materials, and development of fuel cycle strategies. The work presented here focuses on the fuel and preliminary in-core fuel management, where advanced ceramic-ceramic (cercer) dispersion fuels are the main focus, and average burnups to 266 M Wd/kg appear achievable for the reference Si C/(U,TRU)C block/plate fuel. Solid solution (pellet) fuel in composite ceramic clad (Si C/Si C) is also being considered, but remains as a backup due to cladding fabrication challenges, and high centerline temperatures in the fuel. (Author)

Nuclear fuel technology - Determination of uranium in solutions, uranium hexafluoride and solids - Part 2: Iron(II) reduction/cerium(IV) oxidation titrimetric method

International Nuclear Information System (INIS)

2004-01-01

This first edition of ISO 7097-1 together with ISO 7097-2:2004 cancels and replaces ISO 7097:1983, which has been technically revised, and ISO 9989:1996. ISO 7097 consists of the following parts, under the general title Nuclear fuel technology - Determination of uranium in solutions, uranium hexafluoride and solids: Part 1: Iron(II) reduction/potassium dichromate oxidation titrimetric method; Part 2: Iron(II) reduction/cerium(IV) oxidation titrimetric method. This part 2. of ISO 7097 describes procedures for determination of uranium in solutions, uranium hexafluoride and solids. The procedures described in the two independent parts of this International Standard are similar: this part uses a titration with cerium(IV) and ISO 7097-1 uses a titration with potassium dichromate

Nuclear fuel technology - Determination of uranium in solutions, uranium hexafluoride and solids - Part 1: Iron(II) reduction/potassium dichromate oxidation titrimetric method

International Nuclear Information System (INIS)

2004-01-01

This first edition of ISO 7097-1 together with ISO 7097-2:2004 cancels and replaces ISO 7097:1983, which has been technically revised, and ISO 9989:1996. ISO 7097 consists of the following parts, under the general title Nuclear fuel technology - Determination of uranium in solutions, uranium hexafluoride and solids: Part 1: Iron(II) reduction/potassium dichromate oxidation titrimetric method; Part 2: Iron(II) reduction/cerium(IV) oxidation titrimetric method. This part 1. of ISO 7097 describes procedures for the determination of uranium in solutions, uranium hexafluoride and solids. The procedures described in the two independent parts of this International Standard are similar: this part uses a titration with potassium dichromate and ISO 7097-2 uses a titration with cerium(IV)

Innovation for improvement of pedestrian protection as the challenge for the development of front-end structures of passenger cars; Innovationen zur Verbesserung des Fussgaengerschutzes als Herausforderung fuer die Entwicklung von PKW-Vorbaustrukturen

Energy Technology Data Exchange (ETDEWEB)

Kramer, F.; Weidemann, W.; Jansohn, W.; Schneider, M. [EDAG Engineering and Design AG, Fulda (Germany)

2001-07-01

Requirements for improvement of pedestrian protection are the result of real-world accidents and test conditions, which take an important role in development of front-end structures of passenger cars at present, based on legal regulations (EU directives expected in 2005) and on car assessment programmes (application as per EuroNCAP since 1997). Styling and packaging are major considerations in conceptual realisation on a large scale. Furthermore, demands for minimisation of weight and cost have to be considered as marginal conditions. Solutions for this conflict of aims, which results from the new safety requirements and performance criteria for front-end structures, are to be represented and discussed based on concrete examples. (orig.) [German] Anforderungen zur Verbesserung des Fussgaengerschutzes resultieren einerseits aus dem Unfallgeschehen und andererseits aus Versuchsbedingungen, die derzeit auf der Basis von gesetzlichen Regelungen (erwartete EU-Richtlinie etwa im Jahr 2005) und von Sicherheitsbewertungen (Anwendung im Rahmen von EuroNCAP seit 1997) in der Vorbau-Entwicklung von Personenkraftwagen eine bedeutende Rolle einnehmen. Die konzeptionelle Umsetzung tangiert sowohl Styling als auch Packaging in erheblichem Umfang, darueber hinaus sind als Randbedingungen die Forderungen nach der Minimierung von Gewicht und Kosten zu beruecksichtigen. Die Loesungen dieses Zielkonfliktes, deren Wirkungsfeld durch die neuen Sicherheitsanforderungen und die Auslegungskriterien fuer Vorbaustrukturen aufgespannt wird, sollen anhand von konkreten Beispielen dargestellt und diskutiert werden. (orig.)

Mathematical Model of the Jet Engine Fuel System

Directory of Open Access Journals (Sweden)

Klimko Marek

2015-01-01

Full Text Available The paper discusses the design of a simplified mathematical model of the jet (turbo-compressor engine fuel system. The solution will be based on the regulation law, where the control parameter is a fuel mass flow rate and the regulated parameter is the rotational speed. A differential equation of the jet engine and also differential equations of other fuel system components (fuel pump, throttle valve, pressure regulator will be described, with respect to advanced predetermined simplifications.

Mathematical Model of the Jet Engine Fuel System

Science.gov (United States)

Klimko, Marek

2015-05-01

The paper discusses the design of a simplified mathematical model of the jet (turbo-compressor) engine fuel system. The solution will be based on the regulation law, where the control parameter is a fuel mass flow rate and the regulated parameter is the rotational speed. A differential equation of the jet engine and also differential equations of other fuel system components (fuel pump, throttle valve, pressure regulator) will be described, with respect to advanced predetermined simplifications.

Critical experiment program of heterogeneous core composed for LWR fuel rods and low enriched uranyl nitrate solution

International Nuclear Information System (INIS)

Miyoshi, Yoshinori; Yamamoto, Toshihiro; Watanabe, Shouichi; Nakamura, Takemi

2003-01-01

In order to stimulate the criticality characteristics of a dissolver in a reprocessing plant, a critical experiment program of heterogeneous cores is under going at a Static Critical Experimental Facility, STACY in Japan Atomic Energy Research Institute, JAERI. The experimental system is composed of 5w/o enriched PWR-type fuel rod array immersed in 6w/o enriched uranyl nitrate solution. First series of experiments are basic benchmark experiments on fundamental critical data in order to validate criticality calculation codes for 'general-form system' classified in the Japanese Criticality Safety Handbook, JCSHB. Second series of experiments are concerning the neutron absorber effects of fission products related to the burn-up credit Level-2. For demonstrating the reactivity effects of fission products, reactivity effects of natural elements such as Sm, Nd, Eu and 103 Rh, 133 Cs, solved in the nitrate solution are to be measured. The objective of third series of experiments is to validate the effect of gadolinium as a soluble neutron poison. Properties of temperature coefficients and kinetic parameters are also studied, since these parameters are important to evaluate the transient behavior of the criticality accident. (author)

Spent fuel disposal: is the underground the sole solution?

International Nuclear Information System (INIS)

Nachmilner, L.

1997-01-01

The following 4 major approaches to spent fuel disposal are discussed: permanent storage in an underground repository, reprocessing, partitioning and transmutation, and accelerator driven transmutation. It is concluded that underground disposal will remain the basic option for the near future, although pursuing the other methods is certainly worth while. (P.A.)

Supply Chain Based Solution to Prevent Fuel Tax Evasion: Proof of Concept Final Report

Energy Technology Data Exchange (ETDEWEB)

Capps, Gary J [ORNL; Lascurain, Mary Beth [ORNL; Franzese, Oscar [ORNL; Earl, Dennis Duncan [ORNL; West, David L [ORNL; McIntyre, Timothy J [ORNL; Chin, Shih-Miao [ORNL; Hwang, Ho-Ling [ORNL; Connatser, Raynella M [ORNL; Lewis Sr, Samuel Arthur [ORNL; Moore, Sheila A [ORNL

2011-12-01

The goal of this research was to provide a proof-of-concept (POC) system for preventing non-taxable (non-highway diesel use) or low-taxable (jet fuel) petrochemical products from being blended with taxable fuel products and preventing taxable fuel products from cross-jurisdiction evasion. The research worked to fill the need to validate the legitimacy of individual loads, offloads, and movements by integrating and validating, on a near-real-time basis, information from global positioning system (GPS), valve sensors, level sensors, and fuel-marker sensors.

Selenium electrochemistry. Applications in the nuclear fuel cycle

Energy Technology Data Exchange (ETDEWEB)

Maslennikov, A.; Peretroukhine, V. [Russian Academy of Sciences, Moscow (Russian Federation). Inst. of Physical Chemistry; David, F. [Centre National de la Recherche Scientifique (CNRS), 91 - Orsay (France); Lecomte, M. [CEA Centre d' Etudes de la Valle du Rhone, 30 - Marcoule (France). Direction du Cycle du Combustible

1999-07-01

Modern state of selenium electrochemistry is reviewed in respect of the application of electrochemical methods for the study of the behavior of this element and its quantitative analysis in the solutions of nuclear fuel cycle. The review includes the data on the redox potentials of Se in aqueous solutions, and the data on Se redox reactions, occurring at mercury and solid electrodes. Analysis of the available literature data shows that the inverse stripping voltammetry technique for trace Se concentration and determination seems to be the most promising in application for the Se determination in PUREX solutions and in radioactive wastes. The adaptation of the ISV technique for the trace Se concentration and determination in the solutions of the nuclear fuel cycle is indicated as the most prospective goal of the future experimental study. (author)

Mitigating environmental pollution and impacts from fossil fuels: The role of alternative fuels

Energy Technology Data Exchange (ETDEWEB)

Liu, L.; Cheng, S.Y.; Li, J.B.; Huang, Y.F. [Dalhousie University, Halifax, NS (Canada)

2007-07-01

In order to meet the rising global demand for energy, rapid development of conventional fossil fuels (i.e., coal, oil, and natural gas) have been experienced by many nations, bringing dramatic economic benefit and prosperity to fossil-fuel industries as well as well being of human society. However, various fossil-fuel related activities emit huge quantities of gaseous, liquid, and solid waste materials, posing a variety of impacts, risks, and liabilities to the environment. Therefore, on the one hand, control measures are desired for effectively managing pollution issues; on the other hand, it becomes extremely critical to invest efforts in finding promising alternative energy sources as solutions to the possible energy shortage crisis in future. This article focuses on both aspects through: (1) a discussion of waste materials generated from fossil-fuel industries and waste management measures; and (2) an exploration of some well-recognized alternative fuels in terms of their nature, availability, production, handling, environmental performances, and current and future applications. The conclusion restates the urgency of finding replaceable long-term alternatives to the conventional fuels.

PIN99W, Modelling of VVER and PWR Fuel Rod Thermomechanical Behaviour

International Nuclear Information System (INIS)

Valach, M.; Strizhov, P.; Svoboda, R.

2000-01-01

1 - Description of program or function: The Code is developed to describe fuel rod thermomechanical behaviour in operational conditions. The main goal of this code is to calculate fuel temperature, gap conductivity, fission gas release and inner gas pressure. 2 - Methods: - fuel rod temperature response is solved by using one-dimensional finite element method combined with weighted residuals method; - the code involves models describing physical phenomena typical for the fuel irradiated in Light Water Power Reactors (densification, restructuring, fission gas release, swelling and relocation) ; - this code is updated and improves PIN-micro code. 3 - Restrictions on the complexity of the problem: - simplified mechanistic solution; - only steady-state solution; - no cladding failure criterion; - no model for axial fuel-cladding interaction

Revolution by way of technical transfer in the development of locomotive brake systems; Revolutionierung in der Entwicklung von Bremssystemen bei Lokomotiven durch Technologietransfer

Energy Technology Data Exchange (ETDEWEB)

Wright, E.C. [New York Air Brake (United States). Bereich Engineering; Sinn, R. [New York Air Brake (United States). Bereich Elektronik und Software

1997-12-31

With the use of components from other sectors and orientation on the technologies of other fields it has been possible to enhance the standard of electronic braking systems. The reliability of the CCBII is ten times greater than with conventional systems. The physical volume could be reduced by 40 percent and the weight by 30 percent. The CCBII has functional redundancy and the Locotrol Distributed Power System is already integrated. A diagnostics system allows repair times to be reduced to 20 minutes. Production is now commencing and it is planned to make the first deliveries starting from January 1998. (orig.) [Deutsch] Durch das Einbinden von Entwurfsverfahren aus der Luft- und Raumfahrtindustrie sowie der Verwendung von Komponenten aus dem Automobilsektor, hochentwickelter Werkstoffe und Techniken ist es moeglich, neue Wege bei Bremssystemen zu gehen. Der Beitrag beschreibt die Entwicklung einer neuen Generation von computergesteuerten Bremssystemen fuer Lokomotiven. (orig.)

Automotive Fuel Processor Development and Demonstration with Fuel Cell Systems

Energy Technology Data Exchange (ETDEWEB)

Nuvera Fuel Cells

2005-04-15

The potential for fuel cell systems to improve energy efficiency and reduce emissions over conventional power systems has generated significant interest in fuel cell technologies. While fuel cells are being investigated for use in many applications such as stationary power generation and small portable devices, transportation applications present some unique challenges for fuel cell technology. Due to their lower operating temperature and non-brittle materials, most transportation work is focusing on fuel cells using proton exchange membrane (PEM) technology. Since PEM fuel cells are fueled by hydrogen, major obstacles to their widespread use are the lack of an available hydrogen fueling infrastructure and hydrogen's relatively low energy storage density, which leads to a much lower driving range than conventional vehicles. One potential solution to the hydrogen infrastructure and storage density issues is to convert a conventional fuel such as gasoline into hydrogen onboard the vehicle using a fuel processor. Figure 2 shows that gasoline stores roughly 7 times more energy per volume than pressurized hydrogen gas at 700 bar and 4 times more than liquid hydrogen. If integrated properly, the fuel processor/fuel cell system would also be more efficient than traditional engines and would give a fuel economy benefit while hydrogen storage and distribution issues are being investigated. Widespread implementation of fuel processor/fuel cell systems requires improvements in several aspects of the technology, including size, startup time, transient response time, and cost. In addition, the ability to operate on a number of hydrocarbon fuels that are available through the existing infrastructure is a key enabler for commercializing these systems. In this program, Nuvera Fuel Cells collaborated with the Department of Energy (DOE) to develop efficient, low-emission, multi-fuel processors for transportation applications. Nuvera's focus was on (1) developing fuel

Manufacturing method for fuel assembly

International Nuclear Information System (INIS)

Yamaguchi, Takashi.

1997-01-01

In an FBR type reactor, uranium/plutonium mixed oxide fuels (MOX fuels) are used. Nuclear fuel materials containing uranium and plutonium are filled to a portion or all of a plurality of fuel rods. In this case, an equivalent fissile coefficient (B) based on a combustion guarantee method defined by the formula: (B) = (M) · (F) is determined. (M) is a combustion matrix constituted based on the solution of equation of combustion which is a differential equation representing change with time of each of nuclear fuel materials during combustion. (F) is an equivalent fissile coefficient based on a reactivity keeping method which is a coefficient representing a reactivity worth equivalent with plutonium-239. The content of each of the nuclear fuel materials is determined so that the effective multiplication factor at the final stage of the operation cycle is substantially constant by using the equivalent fissile coefficient (B) based on the combustion guarantee method. (I.N.)

Demonstration of an instrumental technique in the measurement of solution weight in the accountability vessels of a fuel reprocessing plant

International Nuclear Information System (INIS)

Nakajima, K.

1977-04-01

Load cells were installed on the input accountability vessel of a commercial reactor fuel reprocessing facility to determine if this proven principle of mass measurement is in fact applicable in such a severe radiation environment over a long period of time. Two other locations selected were the plutonium product nitrate solution accountability vessel and the plutonium product nitrate solution storage vessel. The latter two environments, while not severely radio-active, require a high degree of contamination control. All three vessels are of different geometrical configuration and capacity. Each vessel was carefully calibrated for volume measurements by adding controlled pre-measured increments of water. Measurements were made using the conventional dip-tube manometer system and the load cell - digital voltmeter. Standard deviation of the measurements on the input vessel and the plutonium storage vessel were in both cases 0.3%; for the plutonium accountability vessel 1.9%. Measurements taken of the input vessel during the ''cold run'' over a six-month period using solutions of unirradiated uranium showed a standard deviation of 0.4% and a bias of 0.8% in the summer months and 0.7% and 0.6% respectively in the winter months FINAL STOP CODE

The lumped parameter model for fuel pins

Energy Technology Data Exchange (ETDEWEB)

Liu, W S [Ontario Hydro, Toronto, ON (Canada)

1996-12-31

The use of a lumped fuel-pin model in a thermal-hydraulic code is advantageous because of computational simplicity and efficiency. The model uses an averaging approach over the fuel cross section and makes some simplifying assumptions to describe the transient equations for the averaged fuel, fuel centerline and sheath temperatures. It is shown that by introducing a factor in the effective fuel conductivity, the analytical solution of the mean fuel temperature can be modified to simulate the effects of the flux depression in the heat generation rate and the variation in fuel thermal conductivity. The simplified analytical method used in the transient equation is presented. The accuracy of the lumped parameter model has been compared with the results from the finite difference method. (author). 4 refs., 2 tabs., 4 figs.

Two-dimensional analytical solution for nodal calculation of nuclear reactors

International Nuclear Information System (INIS)

Silva, Adilson C.; Pessoa, Paulo O.; Silva, Fernando C.; Martinez, Aquilino S.

2017-01-01

Highlights: • A proposal for a coarse mesh nodal method is presented. • The proposal uses the analytical solution of the two-dimensional neutrons diffusion equation. • The solution is performed homogeneous nodes with dimensions of the fuel assembly. • The solution uses four average fluxes on the node surfaces as boundary conditions. • The results show good accuracy and efficiency. - Abstract: In this paper, the two-dimensional (2D) neutron diffusion equation is analytically solved for two energy groups (2G). The spatial domain of reactor core is divided into a set of nodes with uniform nuclear parameters. To determine iteratively the multiplication factor and the neutron flux in the reactor we combine the analytical solution of the neutron diffusion equation with an iterative method known as power method. The analytical solution for different types of regions that compose the reactor is obtained, such as fuel and reflector regions. Four average fluxes in the node surfaces are used as boundary conditions for analytical solution. Discontinuity factors on the node surfaces derived from the homogenization process are applied to maintain averages reaction rates and the net current in the fuel assembly (FA). To validate the results obtained by the analytical solution a relative power density distribution in the FAs is determined from the neutron flux distribution and compared with the reference values. The results show good accuracy and efficiency.

SFAK, Unscattered Gamma Self-Absorption from Regular Fuel Rod Assemblies

International Nuclear Information System (INIS)

Wand, H.

1982-01-01

1 - Description of problem or function: Calculation of the self- absorption of unscattered (gamma-) radiation from fuel assemblies which contain a regular arrangement of identical fuel rods. 2 - Method of solution: The point-kernel is integrated over the radiation sources, i.e. the fuel rods. A uniform mesh of integration points is used for each of the fuel rods. 3 - Restrictions on the complexity of the problem: Number of fuel rods is dynamically allocated

Increasing Fuel Efficiency of Direct Methanol Fuel Cell Systems with Feedforward Control of the Operating Concentration

Directory of Open Access Journals (Sweden)

Youngseung Na

2015-09-01

Full Text Available Most of the R&D on fuel cells for portable applications concentrates on increasing efficiencies and energy densities to compete with other energy storage devices, especially batteries. To improve the efficiency of direct methanol fuel cell (DMFC systems, several modifications to system layouts and operating strategies are considered in this paper, rather than modifications to the fuel cell itself. Two modified DMFC systems are presented, one with an additional inline mixer and a further modification of it with a separate tank to recover condensed water. The set point for methanol concentration control in the solution is determined by fuel efficiency and varies with the current and other process variables. Feedforward concentration control enables variable concentration for dynamic loads. Simulation results were validated experimentally with fuel cell systems.

Perspectives of the alcohol fuels in Guatemala

International Nuclear Information System (INIS)

2002-01-01

This presentation overviews the following aspects: antecedents of the production of alcohol fuel in Guatemala as an alternative to imported fuels, also presents current statistics of consumption, importation of liquid fossil fuels, production of alcohol, consumption, trends of consumption mixed with gasoline and yield data. Also problems with environmental impact of CO and CO2 are discussed and possible solutions, incentives to private sector for trading, tax reductions and legislation to support the production are included

Design study and evaluation of fuel fabrication systems for FR fuel cycle

International Nuclear Information System (INIS)

Namekawa, Takashi; Tanaka, Kenya; Kawaguchi, Koichi; Koike, Kazuhiro; Shimuta, Hiroshi; Suzuki, Yoshihiro

2004-01-01

The plant concept for each FBR fuel fabrication system has been constructed and evaluated, which achieves economical improvement, decrease in the environmental burden, better resource utilization, and proliferation resistance by the various innovative techniques employed. The results are as follows: (1) For oxide fuels, the simplified pelletizing method has a high technical feasibility, and it is possible to apply this method to practical process at early stage, because this method is based on wealth results of a conventional method. (2) For oxide fuels, the sphere packing fuel fabrication system by gelation and vibro-compaction processes has the advantage of lesser dispersion of the fine powder due to the use of solution and granule in the process. However this system shoulders additional cost for the liquid waste treatment process to dispose a large bulk of process liquid waste. (3) For the metal fuel, the casting system is generally expected to have high economical efficiency even for small-scale facilities, although verification for fabrication of the TRU alloy slug is required. (author)

Current state of knowledge of water radiolysis effects on spent nuclear fuel corrosion

International Nuclear Information System (INIS)

Christensen, H.; Sunder, S.

2000-07-01

Literature data on the effect of water radiolysis products on spent-fuel oxidation and dissolution are reviewed. Effects of gamma radiolysis, alpha radiolysis, and dissolved O 2 or H 2 O 2 in unirradiated solutions are discussed separately. Also, the effect of carbonate in gamma-irradiated solutions and radiolysis effects on leaching of spent fuel are reviewed. In addition, a kinetic model for calculating the corrosion rates of UO 2 in solutions undergoing radiolysis is discussed. The model gives good agreement between calculated and measured corrosion rates in the case of gamma radiolysis and in unirradiated solutions containing dissolved oxygen or hydrogen peroxide. However, the model fails to predict the results of alpha radiolysis. In a recent study , it was shown that the model gave good agreement with measured corrosion rates of spent fuel exposed in deionized water. The applications of radiolysis studies for geologic disposal of used nuclear fuel are discussed. (author)

Fuel Continuous Mixer ? an Approach Solution to Use Straight Vegetable Oil for Marine Diesel Engines

Directory of Open Access Journals (Sweden)

Đặng Van Uy

2018-03-01

Full Text Available The vegetable oil is well known as green fuel for diesel engines due to its low sunphur content and renewable stock. However, there are some problems raising when vegetable oil is used as fuel for diesel engines such as highly effected by cold weather, lower general efficiency, separation in layer if mixed with diesel oil and so on. To overcome that disadvantiges, the authors propose a new idea that to use a continuous fuel mixer to blend vegetable oil with diesel oil to make so called a mixed fuel supplying to diesel engines inline. In order to ensure a quality of the mixed fuel created by continuous mixer, a homogeneous testing was introduced with believable results. Then, the continuous mixer has been installed into fuel supply system of diesel engine 6LU32 at a lab of Vietnam Maritime University in terms of checking a real operation of the fuel continuous mixer with diesel engine.

Hybridization and control of a mobile direct methanol fuel cell system; Hybridisierung und Regelung eines mobilen Direktmethanol-Brennstoffzellen-Systems

Energy Technology Data Exchange (ETDEWEB)

Wilhelm, Joerg Christoph

2010-07-01

for the dimensioning of the fuel cell as well as of the energy storage unit. Variation of parameters results in a minimum required fuel cell power of 1.3 kW as well as a minimum energy density of 66 Wh/l or a minimum power density of 355 W/l for the energy storage unit, respectively. The high energy density required and the fact that the energy storage unit must always be operated at a partial state of charge leads to faster aging, particularly of lead-acid batteries, so that a lithium battery is eventually chosen as an energy storage unit. (orig.) [German] Direktmethanol-Brennstoffzellen (DMFCs) zeichnen sich dadurch aus, dass sie die chemische Energie des fluessig zugefuehrten Brennstoffs Methanol direkt in elektrische Energie umwandeln. Methanol hat eine hohe Energiedichte und laesst sich vergleichsweise einfach speichern. Aufgrund dieser Vorteile eignen sich Direktmethanol-Brennstoffzellen- Systeme z. B. als Batterieersatz fuer den Bereich leichte Traktion in der kW-Klasse. Da das Nachtanken im Vergleich zum Laden einer Batterie viel schneller realisierbar ist, folgt hieraus ein nahezu unterbrechungsfreier Betrieb. Das Ziel der vorliegenden Arbeit ist es daher ein Direktmethanol-Brennstoffzellen-System fuer den Bereich leichte Traktion zu entwickeln. Die systemtechnische Entwicklung und Charakterisierung eines mobilen Direktmethanol-Brennstoffzellen-Systems erfolgt zuerst allgemein und anschliessend angewandt auf das Beispiel Horizontalkommissionierer aus der Klasse der Flurfoerderfahrzeuge. Hierfuer soll sowohl ein Hybridisierungs- als auch ein Regelungskonzept entwickelt werden. Die gewaehlte Vorgehensweise gliedert sich in die Charakterisierung der Anwendung, die theoretische Konzeptentwicklung und eine abschliessende Systemanalyse mithilfe von Untersuchungen am Teststand und Simulationen. Aus der Charakterisierung folgt der charakteristische Fahrzyklus der Anwendung. Die Eckdaten, wie maximale Peakleistungen beim Beschleunigen und Bremsen sowie die

The verification of PWR-fuel code for PWR in-core fuel management

International Nuclear Information System (INIS)

Surian Pinem; Tagor M Sembiring; Tukiran

2015-01-01

In-core fuel management for PWR is not easy because of the number of fuel assemblies in the core as much as 192 assemblies so many possibilities for placement of the fuel in the core. Configuration of fuel assemblies in the core must be precise and accurate so that the reactor operates safely and economically. It is necessary for verification of PWR-FUEL code that will be used in-core fuel management for PWR. PWR-FUEL code based on neutron transport theory and solved with the approach of multi-dimensional nodal diffusion method many groups and diffusion finite difference method (FDM). The goal is to check whether the program works fine, especially for the design and in-core fuel management for PWR. Verification is done with equilibrium core search model at three conditions that boron free, 1000 ppm boron concentration and critical boron concentration. The result of the average burn up fuel assemblies distribution and power distribution at BOC and EOC showed a consistent trend where the fuel with high power at BOC will produce a high burn up in the EOC. On the core without boron is obtained a high multiplication factor because absence of boron in the core and the effect of fission products on the core around 3.8 %. Reactivity effect at 1000 ppm boron solution of BOC and EOC is 6.44 % and 1.703 % respectively. Distribution neutron flux and power density using NODAL and FDM methods have the same result. The results show that the verification PWR-FUEL code work properly, especially for core design and in-core fuel management for PWR. (author)

Compact Fuel-Cell System Would Consume Neat Methanol

Science.gov (United States)

Narayanan, Sekharipuram; Kindler, Andrew; Valdez, Thomas

2007-01-01

In a proposed direct methanol fuel-cell electric-power-generating system, the fuel cells would consume neat methanol, in contradistinction to the dilute aqueous methanol solutions consumed in prior direct methanol fuel-cell systems. The design concept of the proposed fuel-cell system takes advantage of (1) electro-osmotic drag and diffusion processes to manage the flows of hydrogen and water between the anode and the cathode and (2) evaporative cooling for regulating temperature. The design concept provides for supplying enough water to the anodes to enable the use of neat methanol while ensuring conservation of water for the whole fuel-cell system.

Criticality safety research on nuclear fuel cycle facility

Energy Technology Data Exchange (ETDEWEB)

Miyoshi, Yoshinori [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

2004-07-01

This paper present d s current status and future program of the criticality safety research on nuclear fuel cycle made by Japan Atomic Energy Research Institute. Experimental research on solution fuel treated in reprocessing plant has been performed using two critical facilities, STACY and TRACY. Fundamental data of static and transient characteristics are accumulated for validation of criticality safety codes. Subcritical measurements are also made for developing a monitoring system for criticality safety. Criticality safety codes system for solution and power system, and evaluation method related to burnup credit are developed. (author)

Cogeneration: A solution from energetical auditoring. Cogeneracion: hipotesis de solucion en auditorias energeticas

Energy Technology Data Exchange (ETDEWEB)

Gomara Martinez, E; Riesco Leal, P

1993-01-01

An energetical auditor provides the solutions to avoid environmental problems generated from the consumption of a determined fuel and reduces fuel consumption. One of the solutions is changing the energy source or introducing cogeneration. The author introduces under the point of view of an auditor the reasons to use to generation. (Author)

Analysis of an homogeneous solution reactor for 99 Mo production

International Nuclear Information System (INIS)

Weir, A.; Lopasso, E.; Gho, C.

2007-01-01

The 99m Tc is the more used radioisotope in nuclear medicine, used in 80% of procedures of nuclear medicine in the world. This is due to their characteristics practically ideal for the diagnostic. The 99m Tc is obtained by decay of the 99 Mo, which can produce it by irradiating enriched targets in 98 Mo, or as fission product, irradiating uranium targets or by means of homogeneous solution reactors. The pattern of the used reactor in the neutron analysis possesses a liquid fuel composed of uranyl nitrate dissolved in water with the attach of nitric acid. This solution is contained in a cylindrical recipient of stainless steel reflected with light water. The reactor is refrigerated by means of an helicoidal heat exchanger immersed in the fuel solution. The heat of the fuel is removed by natural convection while the circulation of the water inside the exchanger is forced. The control system of the reactor consists on 6 independent cadmium bars, with followers of water. An auxiliary control system can be the level of the fuel solution inside container tank, but it was not included in the pattern in study. One studies the variations of the reactivity of the system due to different phenomena. An important factor during the normal operation of the reactor is the variation of temperature taking to a volumetric expansion of the fuel and ghastly effects in the same one. Another causing phenomenon of changes in the reactivity is the variation of the concentration of uranium in the combustible solution. An important phenomenon in this type of reactors is the hole fraction in the nucleus I liquidate due to the radiolysis and the possible boil of the water of the combustible solution. Some of the possible cases of abnormal operation were studied as the lost one of coolant in the secondary circuit of the heat exchanger, the introduction and evaporation of water in the nucleus. The reactivity variations were studied using the codes of I calculate MCNP, WIMS and TORT. All the

New process of the preparation of catalyzed gas diffusion electrode for PEM fuel cells based on ultrasonic direct solution spray reaction method

Energy Technology Data Exchange (ETDEWEB)

Oishi, K.; Savadogo, O. [Ecole Polytechnique de Montreal, Montreal, PQ (Canada). Laboratoire de nouveaux materiaux pour l' energie et l' electrochimie

2008-07-01

This paper reported on a newly developed process for in-situ catalyst deposition on gas diffusion electrodes (GDE) for polymer electrolyte fuel cells. This process has the potential to reduce the number of steps for catalyzed GDE fabrication. In addition, the process offers economic advantages for the fuel cell commercialization. In this study, a home-made catalyst maker with ultrasonic spray method was used to prepare a solution of the carbon supported platinum catalyst on the GDL. The sprayed catalyst powder consisted of carbon support. The catalyst particles did not prevent gas flow channels on the GDL. The catalyst layer was shown to be located only on the top surface of the GDL and was not packed into its flow channel. Results of Cross-section SEM image, crystallization, micro structure and electro-catalytic activity for the oxygen reduction reaction were also discussed. 1 ref., 1 fig.

Fuel performance analysis code 'FAIR'

International Nuclear Information System (INIS)

Swami Prasad, P.; Dutta, B.K.; Kushwaha, H.S.; Mahajan, S.C.; Kakodkar, A.

1994-01-01

For modelling nuclear reactor fuel rod behaviour of water cooled reactors under severe power maneuvering and high burnups, a mechanistic fuel performance analysis code FAIR has been developed. The code incorporates finite element based thermomechanical module, physically based fission gas release module and relevant models for modelling fuel related phenomena, such as, pellet cracking, densification and swelling, radial flux redistribution across the pellet due to the build up of plutonium near the pellet surface, pellet clad mechanical interaction/stress corrosion cracking (PCMI/SSC) failure of sheath etc. The code follows the established principles of fuel rod analysis programmes, such as coupling of thermal and mechanical solutions along with the fission gas release calculations, analysing different axial segments of fuel rod simultaneously, providing means for performing local analysis such as clad ridging analysis etc. The modular nature of the code offers flexibility in affecting modifications easily to the code for modelling MOX fuels and thorium based fuels. For performing analysis of fuel rods subjected to very long power histories within a reasonable amount of time, the code has been parallelised and is commissioned on the ANUPAM parallel processing system developed at Bhabha Atomic Research Centre (BARC). (author). 37 refs

Fuel Chemistry Division: progress report for 1985

International Nuclear Information System (INIS)

1988-01-01

Fuel Chemistry Division was formed in May 1985 to give a larger emphasis on the research and development in chemistry of the nuclear fuel cycle. The areas of research in Fuel Chemistry Division are fuel development and its chemical quality control, understanding of the fuel behaviour and post irradiation examinations, chemistry of reprocessing and waste management processes as also the basic aspects of actinide and relevant fission product elements. This report summarises the work by the staff of the Division during 1985 and also some work from the previous periods which was not reported in the progress reports of the Radiochemistry Division. The work related to the FBTR fuel was one of the highlights during this period. In the area of process chemistry useful work has been carried out for processing of plutonium bearing solutions. In the area of mass spectrometry, the determination of trace constituents by spark source mass spectrometry has been a major area of research. Significant progress has also been made in the use of alpha spectromet ry techniques for the determination of plutonium in dissolver solution and other samples. The technology of plutonium utilisation is quite complex and the Division would continue to look into the chemical aspects of this technology and provide the necessary base for future developments in this area. (author)

Aviation Fueling: A Cleaner, Greener Approach

Science.gov (United States)

Hendricks, Robert C.; Bushnell, Dennis M.; Shouse, Dale T.

2010-01-01

Projected growth of aviation depends on fueling where specific needs must be met. Safety is paramount, and along with political, social, environmental and legacy transport systems requirements, alternate aviation fueling becomes an opportunity of enormous proportions. Biofuels sourced from halophytes, algae, cyanobacteria, and weeds using wastelands, waste water, and seawater have the capacity to be drop-in fuel replacements for petroleum fuels. Biojet fuels from such sources solves the aviation CO2 emissions issue and do not compete with food or freshwater needs. They are not detrimental to the social or environmental fabric and use the existing fuels infrastructure. Cost and sustainable supply remains the major impediments to alternate fuels. Halophytes are the near-term solution to biomass/biofuels capacity at reasonable costs; they simply involve more farming, at usual farming costs. Biofuels represent a win-win approach, proffering as they do at least the ones we are studying massive capacity, climate neutral-to-some sequestration, and ultimately, reasonable costs.

Aviation Fueling: A Cleaner, Greener Approach

Directory of Open Access Journals (Sweden)

Robert C. Hendricks

2011-01-01

Full Text Available Projected growth of aviation depends on fueling where specific needs must be met. Safety is paramount, and along with political, social, environmental, and legacy transport systems requirements, alternate aviation fueling becomes an opportunity of enormous proportions. Biofuels—sourced from halophytes, algae, cyanobacteria, and “weeds” using wastelands, waste water, and seawater—have the capacity to be drop-in fuel replacements for petroleum fuels. Biojet fuels from such sources solve the aviation CO2 emissions issue and do not compete with food or freshwater needs. They are not detrimental to the social or environmental fabric and use the existing fuels infrastructure. Cost and sustainable supply remain the major impediments to alternate fuels. Halophytes are the near-term solution to biomass/biofuels capacity at reasonable costs; they simply involve more farming, at usual farming costs. Biofuels represent a win-win approach, proffering as they do—at least the ones we are studying—massive capacity, climate neutral-to-some sequestration, and ultimately, reasonable costs.

Generation of transportation fuel from solid municipal waste plastics

Energy Technology Data Exchange (ETDEWEB)

Sarker, Moinuddin

2010-09-15

Transportation fuels derived from fossil fuels are subjected to the price fluctuations of the global marketplace, and constitute a major expense in the operation of a vehicle. Emissions from the evaporation and combustion of these fuels contribute to a range of environmental problems, causing poor air quality and emitting greenhouse gases that contribute to global warming. Alternative fuels created from domestic sources have been proposed as a solution to these problems, and many fuels are being developed based on biomass and other renewable sources. Natural State Research, Inc. developed different alternative hydrocarbon fuel which is produced from waste plastic materials.

Getting realistic; Endstation Demut

Energy Technology Data Exchange (ETDEWEB)

Meyer, J.P.

2004-01-28

The fuel cell hype of the turn of the millenium has reached its end. The industry is getting realistic. If at all, fuel cell systems for private single-family and multiple dwellings will not be available until the next decade. With a Europe-wide field test, Vaillant intends to advance the PEM technology. [German] Der Brennstoffzellen-Hype der Jahrtausendwende ist verfolgen. Die Branche uebt sich in Bescheidenheit. Die Marktreife der Systeme fuer Ein- und Mehrfamilienhaeuser wird - wenn ueberhaupt - wohl erst im naechsten Jahrzehnt erreicht sein. Vaillant will durch einen europaweiten Feldtest die Entwicklung der PEM-Technologie vorantreiben. (orig.)

Engineering solutions for a reflector change concept in the high-temperature reactor with pebble bed core and OTTO-fueling

International Nuclear Information System (INIS)

Kasper, K.J.

1975-06-01

In the field of reactor engineering an increasing tendency is visible towards a 'repairable reactor'. In the construction of the HTR with spherical fuel elements this fact should already be taken into account at an early stage. Additionally it is possible that in connection with the OTTO-fueling load conditions for the graphite reflector could result which are locally not far away from limiting values. Therefore the removability of the reflector is included in the reactor construction as an accompanying technical step of the physical lay-out of the core. The core arrangements, realized for HTR until recently, are discussed as well as the properties of the graphites used and the operating conditions in the reactors are stated. At the example of the PR 3,000 proposals are offered for the construction of a removable side and top reflector for a pebble bed reactor. Hereby a solution was found which, on one hand allows the changing of the reflector and on the other hand requires no significant increase of the costs for the reactor assembly. Moreover the requirements of reactor operation and of repairability are satisfied in an optimal manner. (orig.) [de

Long Term Management of Spent Fuel from NEK

International Nuclear Information System (INIS)

Kegel, L.; Zeleznik, N.; Lokner, V.

2012-01-01

In 2008 Slovenian national agency for radioactive waste management ARAO started together with Croatian sister organization APO elaboration of a new revision of Decommissioning, Radioactive waste and Spent fuel management program for NPP Krsko. In scope of this work also new studies for spent fuel storage and disposal were prepared in which technical solutions were analyzed and proposed for specific spent fuel (SF) from NPP Krsko. Time schedules for main activities of SF disposal development were elaborated for two alternative scenarios which correspond to normal NPP Krsko operation and 20 - year lifetime extension. All technical activities were financially assessed and costs estimates of SF storage and geological disposal development provided. The prepared studies were verified by international experts in order to confirm the correctness of technical inputs, proposed solutions, time schedules of activities and costs evaluations. The calculated nominal and discounted costs of spent fuel management served for the recalculation of annuities in the integral scenarios of interrelated activities on NPP Krsko decommissioning, LILW and SF management. Besides new first proposal of long-term management of spent fuel from NPP Krsko the joint work also opened additional questions. One of this is time schedule of proposed activities for long term SF management - what were the criteria used in the determination of actions and are they optimal for both countries. How the process of site selection for SF storage or disposal should be prepared having in mind that it will bring many questions in both countries? Is direct disposal of SF still the best solution in current development of nuclear prospects? The paper will present the current development and solutions for SF management from NPP Krsko and will try to answer questions which need to be solved and future development in the SF management.(author).

Sizing stack and battery of a fuel cell hybrid distribution truck

NARCIS (Netherlands)

Bram Veenhuizen; Y. Shen; P.P.J. van den Bosch; Edwin Tazelaar; T. Hofman

2012-01-01

Fuel cell hybrid vehicles are believed to provide a solution to cut down emissions in the long term. They provide local zero-emission propulsion and when the hydrogen as fuel is derived from renewable energy sources, fuel cell hybrids enable well-to-wheel zero-emission transportation,

Fuel reprocessing plant - no solution for the economy of the region

International Nuclear Information System (INIS)

Elvers, G.

1986-01-01

Both for the construction and operation stage, the direct and indirect impact of the fuel reprocessing plant on employment on the whole will be negative. It is not altogether certain either that there will be no adverse effects for the areas of tourism. The top organization of German trade unions (DGB) holds that a different structure-political concept from the one represented by the large-scale project of the fuel reprocessing plant would be more appropriate for the region. Employment in the steel and construction industries must be safeguarded by corresponding programmes, and new employment must be created in small- and medium-size companies. (DG) [de

Calculated k-effectives for light water reactor typical, U + Pu nitrate solution critical experiments

International Nuclear Information System (INIS)

Primm, R.T. III; Mincey, J.F.

1982-01-01

The Department of Energy's Consolidated Fuel Reprocessing Program has as a goal the design of nuclear fuel reprocessing equipment. In order to validate computer codes used for criticality analyses in the design of such equipment, k-effectives have been calculated for several U + Pu nitrate solution critical experiments. As of January 1981, descriptions of 45 unpoisoned, U + Pu solution experiments were available in the open literature. Twelve of these experiments were performed with solutions which have physical characteristics typical of dissolved, light water reactor fuel. This paper contains a discussion of these twelve experiments, a review of the calculational procedure used to determine k-effectives, and the results of the calculations

Management and storage of spent fuel from CEA research reactors

International Nuclear Information System (INIS)

Merchie, F.

1996-01-01

CEA research reactors and their interim spent fuel storage facilities are described. Long-term solutions for spent fuel storage problems, involving wet storage at PEGASE or dry storage at CASCAD, are outlined in some detail. (author)

Asymptotic estimation of reactor fueling optimal strategy

International Nuclear Information System (INIS)

Simonov, V.D.

1985-01-01

The problem of improving the technical-economic factors of operating. and designed nuclear power plant blocks by developino. internal fuel cycle strategy (reactor fueling regime optimization), taking into account energy system structural peculiarities altogether, is considered. It is shown, that in search of asymptotic solutions of reactor fueling planning tasks the model of fuel energy potential (FEP) is the most ssuitable and effective. FEP represents energy which may be produced from the fuel in a reactor with real dimensions and power, but with hypothetical fresh fuel supply, regime, providing smilar burnup of all the fuel, passing through the reactor, and continuous overloading of infinitely small fuel portion under fule power, and infinitely rapid mixing of fuel in the reactor core volume. Reactor fuel run with such a standard fuel cycle may serve as FEP quantitative measure. Assessment results of optimal WWER-440 reactor fresh fuel supply periodicity are given as an example. The conclusion is drawn that with fuel enrichment x=3.3% the run which is 300 days, is economically justified, taking into account that the cost of one energy unit production is > 3 cop/KW/h

Main conditions and effectiveness of gas fuel use for powering of dual fuel IC self-ignition engine

Directory of Open Access Journals (Sweden)

Stefan POSTRZEDNIK

2015-09-01

Full Text Available Internal combustion engines are fuelled mostly with liquid fuels (gasoline, diesel. Nowadays the gaseous fuels are applied as driving fuel of combustion engines. In case of spark ignition engines the liquid fuel (petrol can be totally replaced by the gas fuels. This possibility in case of compression engines is essentially restricted through the higher self-ignition temperatures of the combustible gases in comparison to classical diesel oil. Solution if this problem can be achieved by using of the dual fuel system, where for ignition of the prepared fuel gas - air mixture a specified amount of the liquid fuel (diesel oil should be additionally injected into the combustion chamber. For assurance that the combustion process proceeds without mistakes and completely, some basic conditions should be satisfied. In the frame of this work, three main aspects of this problem are taken into account: a. filling efficiency of the engine, b. stoichiometry of the combustion, c. performance of mechanical parameters (torque, power. A complex analysis of these conditions has been done and some achieved important results are presented in the paper.

Final disposition of MTR fuel

International Nuclear Information System (INIS)

Jonnson, Erik B.

1996-01-01

The final disposition of power reactor fuel has been investigated for a long time and some promising solutions to the problem have been shown. The research reactor fuels are normally not compatible with the zirkonium clad power reactor fuel and can thus not rely on the same disposal methods. The MTR fuels are typically Al-clad UAl x or U 3 Si 2 , HEU resp. LEU with essentially higher remaining enrichment than the corresponding power reactor fuel after full utilization of the uranium. The problems arising when evaluating the conditions at the final repository are the high corrosion rate of aluminum and uranium metal and the risk for secondary criticality due to the high content on fissionable material in the fully burnt MTR fuel. The newly adopted US policy to take back Foreign Research Reactor Spent Fuel of US origin for a period of ten years have given the research reactor society a reasonable time to evaluate different possibilities to solve the back end of the fuel cycle. The problem is, however, complicated and requires a solid engagement from the research reactor community. The task would be a suitable continuation of the RERTR program as it involves both the development of new fuel types and collecting data for the safe long-term disposal of the spent MTR fuel. (author)

Reprocessing method of ceramic nuclear fuels in low-melting nitrate molten salts

International Nuclear Information System (INIS)

Brambilla, G.; Caporali, G.; Zambianchi, M.

1976-01-01

Ceramic nuclear fuel is reprocessed through a method wherein the fuel is dispersed in a molten eutectic mixture of at least two alkali metal nitrates and heated to a temperature in the range between 200 and 300 0 C. That heated mixture is then subjected to the action of a gaseous stream containing nitric acid vapors, preferably in the presence of a catalyst such as sodium fluoride. Dissolved fuel can then be precipitated out of solution in crystalline form by cooling the solution to a temperature only slightly above the melting point of the bath

The fission products palladium and rhodium: Their state in solutions, their behavior in the regeneration of fuel of atomic power stations, and the search for selective extraction techniques

International Nuclear Information System (INIS)

Arseenkov, L.V.; Zakharkin, B.S.; Lunichkina, K.P.; Renard, E.V.; Rogozhkin, V.Yu.; Shorokhov, N.A.

1992-01-01

At the present time many research centers are working on the extraction of noble metals in the form of fission fragments. Consistent data has been obtained on the mass accumulation of noble metals in various forms of processed nuclear fuel. Requirements are noted that must be met for obtaining industrial and economic efficiency in the extraction of noble metals by the Purex process. Presently there is a lack of information on the extraction of noble metals from spent fuel, particularly as far as the nitric acid media of the Purex process are concerned. The authors will discuss individual test observations on simulating systems and real systems with noble metals. The investigations focused on the noble metals of lowest radioactivity, namely palladium and rhodium. The complexity of the chemistry of ruthenium, on the one hand, and the possible selective, clearing distillation of ruthenium tetroxide from nitric acid solutions, on the other hand, make it necessary to focus the attention on the unresolved problems of the extraction of palladium and rhodium. The article further includes discussion on the following topics: noble metals in solutions of purex process, electrochemical operations involving noble metals, extraction systems for rhodium and palladium, separation of palladium from real solutions

Palm oil and derivatives: fuels or potential fuels?

Directory of Open Access Journals (Sweden)

Pioch Daniel

2005-03-01

Full Text Available Scientific and technical information including field trials about uses of palm oil as fuel has been available for more than half a century now. Several ways were investigated, from the simple mixture with petroleum Diesel fuel, to more sophisticated solutions. The quality of vegetable oils in natura as fuel is difficult to assess because of interferences between properties of the triacylglycerols – the main components – and those of the many minor components, their content varying significantly from sample to sample. A methodology set up at Cirad allowed to investigate separately natural triacylglycerols alone and the effect of minor components. In addition to these laboratory experiments, engine test at bench and field trials performed in palm oil producing countries, show that this oil is among the best oils as fuel; palm kernel oil whose chemical and physical properties are very close to those of the best of the series investigated, namely copra oil, should display also very interesting properties as Diesel biofuel. Both oils do require external adaptation of the engine when using an indirect injection type engine but even heavier adaptations for a direct injection model. Thus for use as Diesel fuel palm and palm kernel oils are suitable for captive fleets or for engine gensets, to balance the adaptation cost by a scale-up effect either on the number of identical engines or on the nominal vegetable oil consumption per set. Direct use of palm et palm kernel oils fits very well with technical and economical conditions encountered in remote areas. It is also possible to mix palm oil to Diesel fuel either as simple blend or as micro-emulsion. Out of the direct use, palm oil methyl or ethyl ester, often referred to as biodiesel, displays properties similar to those of petroleum Diesel fuel. This technical solution which is suitable to feed all kinds of standard compression ignited engines requires a chemical plant for carrying out the

Determination of sulfur content in fuels

International Nuclear Information System (INIS)

Daucik, P.; Zidek, Z.; Kalab, P.

1998-01-01

The sulfur content in fuels, Diesel fuels, and in the solutions of dibutylsulfide in a white oil was determined by various methods. The results obtained by elemental analysis have shown that the method is not advisable for the determination of sulfur in fuels. A good agreement was found by comparing the results in the determination of the sulfur by Grote-Krekeler's and Hermann-Moritz's methods and by the energy-dispersive X-ray fluorescence analysis. The last method is the modern, comfortable, and timesaving method enabling the fast and precise determination of sulfur contents in the various types of samples. (authors)

Method of making nuclear fuel bodies

International Nuclear Information System (INIS)

Davis, D.E.; Leary, D.F.

1977-01-01

A method of making nuclear fuel bodies is described comprising: providing particulate graphite having a particle size not greater than about 1500 microns; impregnating the graphite with a polymerizable organic resin in liquid form; treating the impregnated particles with a hot aqueous acid solution to pre-cure the impregnated resin and to remove excess resin from the surfaces of said graphite particles; heating the treated particles to polymerize the impregnant; blending the impregnated particles with particulate nuclear fuel; and forming a nuclear fuel body by joining the blend of particles into a cohesive mass using a carbonaceous binder

Dissolution studies of spent nuclear fuels

International Nuclear Information System (INIS)

1991-02-01

To obtain quantitative data on the dissolution of high burnup spent nuclear fuel, dissolution study have been carried out at the Department of Chemistry, JAERI, from 1984 under the contract with STA entitled 'Reprocessing Test Study of High Burnup Fuel'. In this study PWR spent fuels of 8,400 to 36,100 MWd/t in averaged burnup were dissolved and the chemical composition and distribution of radioactive nuclides were measured for insoluble residue, cladding material (hull), off-gas and dissolved solution. With these analyses basic data concerning the dissolution and clarification process in the reprocessing plant were accumulated. (author)

Surface coating Zr or Zr alloy nuclear fuel elements

International Nuclear Information System (INIS)

Donaghy, R.E.; Sherman, A.H.

1980-01-01

A method is disclosed for preventing stress corrosion cracking or metal embrittlement of a zirconium or zirconium alloy container that is to be coated on the inside surface with a layer of a metal such as copper, a copper alloy, nickel, or iron and used for holding nuclear fuel material as a nuclear fuel element. The zirconium material is etched in an etchant solution, desmutted mechanically or ultrasonically, oxidized to form an oxide coating on the zirconium, cleaned in an aqueous alkaline cleaning solution, activated for electroless deposition of a metal layer and contacted with an electroless metal plating solution. This method provides a boundary layer of zirconium oxide between the zirconium container and the metal layer. (author)

Partially closed fuel cycle of WWER-440

International Nuclear Information System (INIS)

Darilek, P.; Sebian, V.; Necas, V.

2002-01-01

Position of nuclear energy at the energy sources competition is characterised briefly. Multi-tier transmutation system is outlined out as effective back-end solution and consequently as factor that can increase nuclear energy competitiveness. LWR and equivalent WWER are suggested as a first tier reactors. Partially closed fuel cycle with combined fuel assemblies is briefed. Main back-end effects are characterised (Authors)

The nuclear fuel cycle

International Nuclear Information System (INIS)

Patarin, L.

2002-01-01

This book treats of the different aspects of the industrial operations linked with the nuclear fuel, before and after its use in nuclear reactors. The basis science of this nuclear fuel cycle is chemistry. Thus a recall of the elementary notions of chemistry is given in order to understand the phenomena involved in the ore processing, in the isotope enrichment, in the fabrication of fuel pellets and rods (front-end of the cycle), in the extraction of recyclable materials (residual uranium and plutonium), and in the processing and conditioning of wastes (back-end of the fuel cycle). Nuclear reactors produce about 80% of the French electric power and the Cogema group makes 40% of its turnover at the export. Thus this book contains also some economic and geopolitical data in order to clearly position the stakes. The last part, devoted to the management of wastes, presents the solutions already operational and also the research studies in progress. (J.S.)

Innovation in the fuel cycle industry

International Nuclear Information System (INIS)

Lamorlette, Guy

1998-01-01

The fuel cycle industry will have to adapt to the production of new fuel and in the same time will have to improve its performance. Innovation will be a key factor of success. Innovation must be driven by the needs of the fuel cycle industry to achieve. The fuel cycle requirement of tomorrow, Innovative processes for mining high grade uranium, Innovative enrichment process, Sorting the pellets at Melox plant, Innovation in action, and Innovative waste management in la Hague are presented. A number of innovative solutions are already implemented and are in action on industrial facilities. As problems are becoming more and more tough to address, international cooperation will be required. The fuel cycle industry, as a part of the nuclear power industry, is committed to seek improvements through performance upgrade and innovation. (Cho. G. S.). 10 refs., 4 figs

The impact of new cathode materials relative to baseline performance of microbial fuel cells all with the same architecture and solution chemistry

KAUST Repository

Yang, Wulin

2017-04-21

Differences in microbial fuel cell (MFC) architectures, materials, and solution chemistries, have previously hindered direct comparisons of improvements in power production due to new cathode materials. However, one common reactor design has now been used in many different laboratories around the world under similar operating conditions based on using: a graphite fiber brush anode, a platinum cathode catalyst, a single-chamber cube-shaped (4-cm) MFC with a 3-cm diameter anolyte chamber, 50 mM phosphate buffer, and an acetate fuel. Analysis of several publications over 10 years from a single laboratory showed that even under such identical operational conditions, maximum power densities varied by 15%, with an average of 1.36 ± 0.20 W m–2 (n=24), normalized to cathode projected area (34 W m–3 liquid volume). In other laboratories, maximum power was significantly less, with an average of 1.03 ± 0.46 W m–2 (n=11), despite identical conditions. One likely reason for the differences in power is cathode age. Power production with Pt catalyst cathodes significantly declined after one month of operation or more to 0.87 ± 0.31 W m–2 (n=18) based on studies where cathode aging was examined, while in many studies the age of the cathode was not reported. Using these studies as a performance baseline, we review the claims of improvements in power generation due to new anode or cathode materials, or changes in solution conductivities and substrates.

Elements of comparison between different inert matrix fuels towards plutonium use and safety coefficients

International Nuclear Information System (INIS)

Baldi, St.; Porta, J.

2000-08-01

This work deals with the CERMET fuels, chosen for their good behaviour under irradiation and their high thermal conductivity. The kinetic coefficients have been particularly studied. Comparisons have been made with other solutions using other composite fuels in particular the solid solutions and the ROX solution. The core control requiring an heterogeneous assembly, we propose an assembly whose characteristics are compared with those of the APA reference. (O.M.)

In-Core Fuel Managements for PWRs: Investigation on solution for optimal utilization of PWR fuel through the use of fuel assemblies with differently enriched 235U fuel pins

International Nuclear Information System (INIS)

Caprioli, Sara

2004-04-01

A possibility for more efficient use of the nuclear fuel in a pressurized water reactor is investigated. The alternative proposed here consists of the implementation of PWR fuel assemblies with differently enriched 235 U fuel pins. This possibility is examined in comparison with the standard assembly design. The comparison is performed both in terms of single assembly performance and in the terms of nuclear reactor core performance and fuel utility. For the evaluation of the actual performance of the new assembly types, 5 operated fuel core sequences of R3 (Ringhals' third unit), for the period 1999 - 2004 (cycles 17 - 21) were examined. For every cycle, the standard fresh fuel assemblies have been identified and taken as reference cases for the study of the new type of assemblies with differently enriched uranium rods. In every cycle, assemblies with and without burnable absorber are freshly loaded into the core. The axial enrichment distribution is kept uniform, allowing for a radial (planar) enrichment level distribution only. At an assembly level, it has been observed that the implementation of the alternative enrichment configuration can lead to lower and flatter internal peaking factor distribution with respect to the uniformly enriched reference assemblies. This can be achieved by limiting the enrichment levels distribution to a rather narrow range. The highest enrichment level chosen has the greatest impact on the power distribution of the assemblies. As it increases, the enrichment level drives the internal peaking factor to greater values than in the reference assemblies. Generally, the highest enrichment level that would allow an improvement in the power performance of the assembly lies between 3.95 w/o and 4.17 w/o. The highest possible enrichment level depends on the average enrichment of the overall assembly, which is kept constant to the average enrichment of the reference assemblies. The improvements that can be obtained at this level are rather

News technology utilization fossil fuel

Directory of Open Access Journals (Sweden)

Blišanová Monika

2004-09-01

Full Text Available Fossil fuel – “alternative energy“ is coal, petroleum, natural gas. Petroleum and natural gas are scarce resources, but they are delimited. Reserves petroleum will be depleted after 39 years and reserves natural gas after 60 years.World reserves coal are good for another 240 years. Coal is the most abundant fossil fuel. It is the least expensive energy source for generating electricity. Many environmental problems associated with use of coal:in coal production, mining creates environmental problems.On Slovakia representative coal only important internal fuel – power of source and coal is produced in 5 locality. Nowadays, oneself invest to new technology on utilization coal. Perspective solution onself shows UCG, IGCC.

RTR spent fuel treatment and final waste storage

International Nuclear Information System (INIS)

Thomasson, J.

2000-01-01

A number of RTR operators have chosen in the past to send their spent fuel to the US in the framework of the US take back program. However, this possibility ends as of May 12th, 2006. 3 different strategies are left for managing RTR spent fuel: extended storage, direct disposal and treatment-conditioning through reprocessing. Whilst former strategies raise a number of uncertainties, the latter already offers a management solution. It features two advantages. It benefits from the long experience of existing flexible industrial facilities from countries like France. Secondly, it offers a dramatic volume reduction of the ultimate waste to be stored under well-characterized, stable and durable forms. RTR spent fuel management through reprocessing-conditioning offers a durable management solution that can be fully integrated in whatever global radioactive waste management policy, including ultimate disposal

Storage experience in Hungary with fuel from research reactors

International Nuclear Information System (INIS)

Gado, J.; Hargitai, T.

1996-01-01

In Hungary several critical assemblies, a training reactor and a research reactor have been in operation. The fuel used in the research and training reactors are of Soviet origin. Though spent fuel storage experience is fairly good, medium and long term storage solutions are needed. (author)

Spent fuel management in Spain

International Nuclear Information System (INIS)

Gonzalez, J.L.

2002-01-01

The spent fuel management strategy in Spain is presented. The strategy includes temporary solutions and plans for final disposal. The need for R and D including partitioning and transmutation, as well as the financial constraints are also addressed. (author)

Behavior of iodine in the dissolution of spent nuclear fuels

Energy Technology Data Exchange (ETDEWEB)

Sakurai, Tsutomu; Komatsu, Kazunori; Takahashi, A. [Japan Atomic Energy Research Institute, Ibaraki-ken (Japan)

1997-08-01

The results of laboratory-scale experiments concerning the behavior of iodine in the dissolution of spent nuclear fuels, which were carried out at the Japan Atomic Energy Research Institute, are summarized. Based on previous and new experimental results, the difference in quantity of residual iodine in the fuel solution between laboratory-scale experiments and reprocessing plants is discussed, Iodine in spent fuels is converted to the following four states: (1) oxidation into I{sub 2} by nitric acid, (2) oxidation into I{sub 2} by nitrous acid generated in the dissolution, (3) formation of a colloid of insoluble iodides such as AgI and PdI{sub 2}, and (4) deposition on insoluble residue. Nitrous acid controls the amount of colloid formed. As a result, up to 10% of iodine in spent fuels is retained in the fuel solution, up to 3% is deposited on insoluble residue, and the balance volatilizes to the off-gas, Contrary to earlier belief, when the dissolution is carried out in 3 to 4 M HNO{sub 3} at 100{degrees}C, the main iodine species in a fuel solution is a colloid, not iodate, Immediately after its formation, the colloid is unstable and decomposes partially in the hot nitric acid solution through the following reaction: AgI(s) + 2HNO{sub 3}(aq) = {1/2}I{sub 2}(aq) + AgNO{sub 3}(aq) + NO{sub 2}(g) + H{sub 2}O(1). For high concentrations of gaseous iodine, I{sub 2}(g), and NO{sub 2}, this reaction is reversed towards formation of the colloid (AgI). Since these concentrations are high near the liquid surface of a plant-scale dissolver, there is a possibility that the colloid is formed there through this reversal, Simulations performed in laboratory-scale experiments demonstrated this reversal, This phenomenon can be one reason the quantity of residual iodine in spent fuels is higher in reprocessing plants than in laboratory-scale experiments. 17 refs., 5 figs., 3 tabs.

Unterrichtsentwurf: Die Entwicklung eines nationalen Identitätsbewusstseins in den von Napoleon besetzten Ländern

Directory of Open Access Journals (Sweden)

Natalie Fridrich

2012-05-01

Full Text Available Nathalie Friedrichs proposes the following lesson plan for the senior classes of the German Gymnasium (grammar-school: „Die Entwicklung eines nationalen Identitätsbewusstseins in den von Napoleon besetzten Ländern“ (The Development of a National Sense of Identity in the Countries Occupied by Napeoleon.The central question, however, is whether this new German national consciousness at the dawn of the 19th century can be traced back to Napoleon’s reign in the Rhineland region or whether it emerged during the wars of liberation as a result of a firm rejection of Napoleon.The following materials will be given to the pupils beforhand: A short preparatory text with essential background information, a pithy quote , and two historical sources, namely the appeal of Ludwig Adolf Peter Graf von Sayn-Wittgenstein to support the war of liberation, and another more francophile source by the physician Adolf Kußmaul. The latter source points in the direction of a positive experience during the time of French occupation and therefore relativises the claim of a German patriotism as a direct result of the war against France. From a didactical viewpoint, the lesson aims to develop the prerequisites for a critical analysis of historical source texts and different points of view on the topic. Finally, a table listing the respective pros and cons of the Napoleonic arguments is sketched out, visualising the perspectives of the students and leading to the final discussion, which should produce answers to the questions of the role of Napoleon for the Germans.

Proliferation Resistant Nuclear Reactor Fuel

International Nuclear Information System (INIS)

Gray, L.W.; Moody, K.J.; Bradley, K.S.; Lorenzana, H.E.

2011-01-01

Global appetite for fission power is projected to grow dramatically this century, and for good reason. Despite considerable research to identify new sources of energy, fission remains the most plentiful and practical alternative to fossil fuels. The environmental challenges of fossil fuel have made the fission power option increasingly attractive, particularly as we are forced to rely on reserves in ecologically fragile or politically unstable corners of the globe. Caught between a globally eroding fossil fuel reserve as well as the uncertainty and considerable costs in the development of fusion power, most of the world will most likely come to rely on fission power for at least the remainder of the 21st century. Despite inevitable growth, fission power faces enduring challenges in sustainability and security. One of fission power's greatest hurdles to universal acceptance is the risk of potential misuse for nefarious purposes of fissionable byproducts in spent fuel, such as plutonium. With this issue in mind, we have discussed intrinsic concepts in this report that are motivated by the premise that the utility, desirability, and applicability of nuclear materials can be reduced. In a general sense, the intrinsic solutions aim to reduce or eliminate the quantity of existing weapons usable material; avoid production of new weapons-usable material through enrichment, breeding, extraction; or employ engineering solutions to make the fuel cycle less useful or more difficult for producing weapons-usable material. By their nature, these schemes require modifications to existing fuel cycles. As such, the concomitants of these modifications require engagement from the nuclear reactor and fuel-design community to fully assess their effects. Unfortunately, active pursuit of any scheme that could further complicate the spread of domestic nuclear power will probably be understandably unpopular. Nevertheless, the nonproliferation and counterterrorism issues are paramount, and

Prospects for development of fuel cells

Directory of Open Access Journals (Sweden)

В. М. Шабер

2017-10-01

Full Text Available The article is devoted to the solution of a complex of problems that arise in small and medium-scale treatment complexes, gas production plants and small and medium-capacity power plants associated with the processing of crude methane and the possibility of reducing the greenhouse effect.The economic feasibility of the development of fuel cells (FC on raw biomethane was demonstrated by the authors in previous publications.The specificity of the solution of problems is focused on small and medium-scale treatment complexes, gas production plants and small and medium power plants.The aim of the study is to show the possibility of solving a multicomponent task of developing fuel cells, including the experimental determination of the actual use of sodium formate as a reducing agent for the production of electricity in a fuel cell (FC.Results are the following: the possibility of solving the issues of reducing greenhouse gas emissions into the atmosphere during processing of waste products of human vital activity is proved. A method for converting methane and carbon dioxide emissions into useful products is shown.

CERCA'S experience in UMO fuel manufacturing

International Nuclear Information System (INIS)

Jarousse, Ch.; Lavastre, Y.; Grasse, M.

2003-01-01

Considered as a suitable solution for non-proliferation and reprocessing purposes, UMo fuel has been chosen and studied by the RERTR program since 1996. Involved in the RERTR fuel developments since 1978, with more than 20 years of U 3 SI 2 fuel production, and closely linked to the French Commissariat a l'Energie Atomique, CERCA was able to define properly, from the beginning, the right R and D actions plan for UMo fuel development. CERCA has already demonstrated during the last 4 years its ability to manufacture plates and fuel elements with high density UMo fuel. UMo full size plates produced for 4 irradiation experiments in 3 European reactors afforded us a unique experience. In addition, as a main part of our R and D effort, we have always studied in depth a key part of the CERCA process outline which is the plate rolling stage. After some preliminary investigation in order to define the phenomenological model describing the behavior of the fuel core when rolling, we have developed a rolling digital simulator. (author)

Preparation of acid deficient solutions of uranyl nitrate and thorium nitrate by steam denitration

International Nuclear Information System (INIS)

Yamagishi, Shigeru; Takahashi, Yoshihisa

1996-01-01

Acid deficient heavy metal (HM) nitrate solutions are often required in the internal gelation processes for nuclear fuel fabrication. The stoichiometric HM-nitrate solutions are needed in a sol-gel process for fuel fabrication. A method for preparing such nitrate solutions with a controlled molar ratio of nitrate/metal by denitration of acid-excess nitrate solutions was developed. The denitration was conducted by bubbling a nitrate solution with a mixture of steam+Ar. It was found that steam was more effective for the denitration than Ar. The acid deficient uranyl nitrate solution with nitrate/U=1.55 was yielded by steam bubbling, while not by only Ar bubbling. As for thorium nitrate, acid deficient solutions of nitrate/Th≥3.1 were obtained by steam bubbling. (author)

Minimally refined biomass fuel. [carbohydrate-water-alcohol mixture

Energy Technology Data Exchange (ETDEWEB)

Pearson, R.K.; Hirschfeld, T.B.

1981-03-26

A minimally refined fluid composition, suitable as a fuel mixture and derived from biomass material, is comprised of one or more water-soluble carbohydrates such as sucrose, one or more alcohols having less than four carbons, and water. The carbohydrate provides the fuel source; water-solubilizes the carbohydrate; and the alcohol aids in the combustion of the carbohydrate and reduces the viscosity of the carbohydrate/water solution. Because less energy is required to obtain the carbohydrate from the raw biomass than alcohol, an overall energy savings is realized compared to fuels employing alcohol as the primary fuel.

Operation experience of the advanced fuel assemblies at Unit 1 of Volgodonsk NPP within four fuel cycles

International Nuclear Information System (INIS)

Vasilchenko, I.; Kobelev, S.; Kushmanov, S.

2006-01-01

The first commissioning of Volgodonsk NPP Unit 1 with standard reactor WWER-1000 (project V-320) was in 2001. The reactor core, starting from the first fuel charge, was arranged completely with Advanced Fuel Assemblies (AFAs). In this way, it is possible to obtain the experience in startup and operation of the core, completely arranged with AFAs, and also to get a possibility of performing the comprehensive check for justification of newly commissioned units and justification of design solutions accepted in the design of reactor core for Taiwan NPP, Bushehr NPP and Kudankulam NPP. The first fuel charge of the Volgodonsk NPP Unit 1 is a reference and unified for Tiawan NPP (V-428), Bushehr NPP (V-446), Kudankulam NPP(V-412) with small differences caused by design features of RP V-320. The first core charge of Unit 1 of Volgodonsk NPP was arranged of 163 AFAs, comprising 61 CPS ARs and 42 BAR bundles. The subsequent fuel charges were arranged of AFAs with gadolinium oxide integrated into fuel instead of BAR. By 2005 the results of operation of the core at Unit 1 of Volgodonsk NPP during four fuel cycles showed that AFA is sufficiently reliable and serviceable. The activity of the primary coolant of the Volgodonsk NPP is at stable low level. During the whole time of the core operation of the Volgodonsk NPP Unit 1 no leaky AFAs were revealed. The modifications of the internals, made during pre-operational work, are reasonable and effective to provide for fuel mechanical stability in the course of operation. The modifications, made in AFA structure during operation of the Volgodonsk NPP Unit 1, are aimed at improving the service and operational reliability of its components. Correctness of the solutions taken is confirmed by AFAs operation experience both at the Volgodonsk NPP, and at other operating Russian NPPs

Molecular-Dynamic Simulation In Substation Of Advanced Fuel With Improved Properties

Energy Technology Data Exchange (ETDEWEB)

Kolokol, Alexander S.; Shimkevich, Alexander L. [Russian Research Center ' Kurchatov Institute' , 1 Kurchatov Sq. Moscow 123182 (Russian Federation)

2008-07-01

A disadvantage of the uranium dioxide fuel is very low thermal conductivity than the one of nitride, carbide, metal fuel, and cermets as composites, UO{sub 2}+Me, due to the portion in thermal conductivity of their electronic conductivity and high phonon mobility. An investigation of the microstructure and atomic dynamics of solid solutions as well as the physical and chemical processes in them will make it possible to adjust the properties of the solutions in steps according to prescribed indicators by using alloying additives. The concept for designing an oxide fuel may be promising for the development of a new generation of nuclear reactors. In developing the methods for designing reactor materials as to the nuclear fuel, microscopic structure improving its thermal and physical properties is formulated here. (authors)

Molecular-Dynamic Simulation In Substation Of Advanced Fuel With Improved Properties

International Nuclear Information System (INIS)

Kolokol, Alexander S.; Shimkevich, Alexander L.

2008-01-01

A disadvantage of the uranium dioxide fuel is very low thermal conductivity than the one of nitride, carbide, metal fuel, and cermets as composites, UO 2 +Me, due to the portion in thermal conductivity of their electronic conductivity and high phonon mobility. An investigation of the microstructure and atomic dynamics of solid solutions as well as the physical and chemical processes in them will make it possible to adjust the properties of the solutions in steps according to prescribed indicators by using alloying additives. The concept for designing an oxide fuel may be promising for the development of a new generation of nuclear reactors. In developing the methods for designing reactor materials as to the nuclear fuel, microscopic structure improving its thermal and physical properties is formulated here. (authors)

Looking to nature for solutions

Science.gov (United States)

Turner, Will R.

2018-01-01

Completely stopping fossil fuel use may not be enough to avoid dangerous climate change. Recent research on the mitigation potential of conservation, restoration, and improved land management demonstrates that natural solutions can reduce emissions and remove atmospheric CO2 while safeguarding food security and biodiversity.

The optimum fuel and power distribution for a PWR burnup cycle

International Nuclear Information System (INIS)

Stillman, J.A.

1989-01-01

A method was developed to determine the optimum fuel and power distributions for a PWR burnup cycle. The backward diffusion calculation [1] and the Core-wise Green's Function [2] method were used for the core model which provided analytic derivatives for solving the nonlinear optimization problem using successive linear programming [3] methods. The solution algorithm consisted of a reverse depletion strategy which begins at the end of cycle and solves simultaneously for the optimal fuel and burnable absorber distributions while the core is depleted to the beginning of cycle. The resulting optimal solutions minimize the required fissile fuel inventory and burnable absorber loading for a PWR

A decade of fuel poverty

Energy Technology Data Exchange (ETDEWEB)

Anon,

1992-01-01

Neighbourhood Energy Action was established in 1981 to develop practical solutions to the problem of fuel poverty. The scale of fuel poverty was evident even then. In that year 2.3. million households received a weekly Heating Addition to help heat their homes, at an annual cost of Pound 260 million, 48,000 Supplementary Benefit claimants received emergency cold weather payments, 151,000 households were disconnected from their gas or electricity supply, and local authority expenditure on energy efficiency improvements halved to Pound 15 million. (author).

Characterization of graphite-matrix pulsed reactor fuels

International Nuclear Information System (INIS)

Karnes, C.H.; Marion, R.H.

1976-01-01

The performance of the Annular Core Pulsed Reactor (ACPR) is being upgraded in order to accommodate higher fluence experiments for fast reactor fuel element transient and safety studies. The increased fluence requires a two-zone core with the inner zone containing fuel having a high enthalpy and the capability of withstanding very high temperatures during both pulsed and steady state operation. Because the fuel is subjected to a temperature risetime of 2 to 5 ms and to a large temperature difference across the diameter, fracture due to thermal stresses is the primary failure mode. One of the fuels considered for the high enthalpy inner region is a graphite-matrix fuel containing a dispersion of uranium--zirconium carbide solid solution particles. A program was initiated to optimize the development of this class of fuel. This summary presents results on formulations of fuel which have been fabricated by the Materials Technology Group of the Los Alamos Scientific Laboratory

Development of process technology for large-area thin-film solar modules based on compound semiconductors. Final report; Entwicklung der technologischen Grundlagen fuer grosse Photovoltaikmodule auf Basis von Duennschicht-Verbindungshalbleitern. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Maurus, H.; Lechner, P.; Geyer, R.; Ruebel, H.; Schade, H.; Psyk, W.; Frammelsberger, W.; Berthold, W.; Eichner, C.; Heckel, E.; Huber, R.; Labudde-Eibl, H.; Raith, S.; Schenk, B.; Ullrich, H.

1998-06-01

dabei die Grundlagenentwicklungen des Instituts fuer physikalische Elektronik der Universitaet Stuttgart (IPE) und des ZSW einerseits und die Erfahrungen der PST auf den Gebieten der grossflaechigen Modulfertigung andererseits. Fuer jede Einzelschicht eines Moduls (Rueckkontakt Mo, Absorber CIS, Anpassungsschicht CdS o.ae. und Fensterschicht ZnO) wurden Anlagen und Verfahren entwickelt, die eine hohe Qualitaet der Eigenschaften auf Flaechen bis 30x30 cm{sup 2} gewaehrleisten. Die monolithische Integration der Solarmodule durch geeignete Strukturierungsverfahren wie Laser-Scribing, mechanisches Ritzen und Lift-Off-Verfahren wurden untersucht und optimiert. Die Projektschwerpunkte bei PST waren die grossflaechige Abscheidung des Mo-Rueckkontaks und seine nachfolgende Strukturierung, Beitraege zur Entwicklung der ZnO-Fensterschicht und die Entwicklung der Modultechnik. Die hier zugeordneten Arbeitspakete waren die Randentschichtung, die Kontaktierung, die Laminierung, die Kabeldurchfuehrung, die Modulcharakterisierung und der Klimatest. Das Projektziel, naemlich die Entwicklung der Verfahrens- und Anlagentechnik (Basistechnologie) zur Herstellung grossflaechiger Module (30x30 cm{sup 2}) mit einem Wirkungsgrad von 10-12% wurde erreicht (bestes Modul: {eta}=11.7 Apertur). (orig.)

MTR spent fuel back-end - Cogema's long-term commitment

International Nuclear Information System (INIS)

Thomasson, J.

1998-01-01

MTR spent fuel back end has been subject to many reversal and uncertainties in the past 10 years. Until the end of 1988, US obligated materials were subject to the Off site Fuels Policy (OFP). Under this policy, spent fuels were returned to USA, and were reprocessed there. This OFP took end the 31th of December 1988, and Research Reactor's operators had to implement others solutions: On site storage or Reprocessing in Europe. Meanwhile the RERTR Program was leading to a new LEU fuel to replace HEU aluminide. This new silicide fuel has one main drawback: it cannot be reprocessed in working plants without some process main line modifications. Fortunately, a new Research Reactors spent fuels return policy has been set up by the US in the early 1996. This new policy applies to all reactors converted or that have agreed to convert to LEU, and reactors operating with HEU for which no suitable LEU is available. It covers all the spent fuels discharged until 2006/05/12. But after that period of time, each reactor will be fully responsible for its spent fuels. Since the end of 1996, COGEMA is proposing reprocessing services for Aluminides spent fuels, based on the La Hague capability. This COGEMA answer is for the long term, as the La Hague plant has a good load for the coming years, including the first decade of the next century. Further, this activity benefits from a strong R and D support, that allowed fulfilling the evolutive needs of our customers, and gives us the ability to adapt the plant to the future market. Taking advantage of this flexibility, COGEMA offers Research Reactors' operators a long-term commitment. Already two reactors' operators have chosen to contract with COGEMA for the whole life of their reactors. The contracts execution is under progress and the first transportation will take place soon. Beside today's services, COGEMA is involved in R and D activities to support new fuels development enhancing present LEU performances and having the ability to

Study of Maxwell–Wagner (M–W) relaxation behavior and hysteresis observed in bismuth titanate layered structure obtained by solution combustion synthesis using dextrose as fuel

International Nuclear Information System (INIS)

Subohi, Oroosa; Shastri, Lokesh; Kumar, G.S.; Malik, M.M.; Kurchania, Rajnish

2014-01-01

Graphical abstract: X-ray diffraction studies show that phase formation and crystallinity was reached only after calcinations at 800 °C. Dielectric constant versus temperature curve shows ferroelectric to paraelectric transition temperature (T c ) to be 650 °C. Complex impedance curves show deviation from Debye behavior. The material shows a thin PE Loop with low remnant polarization due to high conductivity in the as prepared sample. - Highlights: • Bi 4 Ti 3 O 12 is synthesized using solution combustion technique with dextrose as fuel. • Dextrose has high reducing capacity (+24) and generates more no. of moles of gases. • Impedance studies show that the sample follows Maxwell–Wagner relaxation behavior. • Shows lower remnant polarization due to higher c-axis ratio. - Abstract: Structural, dielectric and ferroelectric properties of bismuth titanate (Bi 4 Ti 3 O 12 ) obtained by solution combustion technique using dextrose as fuel is studied extensively in this paper. Dextrose is used as fuel as it has high reducing valancy and generates more number of moles of gases during the reaction. X-ray diffraction studies show that phase formation and crystallinity was reached only after calcinations at 800 °C. Dielectric constant versus temperature curve shows ferroelectric to paraelectric transition temperature (T c ) to be 650 °C. The dielectric loss is very less (tan δ < 1) at lower temperatures but increases around T c due to structural changes in the sample. Complex impedance curves show deviation from Debye behavior. The material shows a thin PE Loop with low remnant polarization due to high conductivity in the as prepared sample

Nuclear fuel technology - Determination of milligram amounts of plutonium in nitric acid solutions - Potentiometric titration with potassium dichromate after oxidation by Ce(IV) and reduction by Fe(II)

International Nuclear Information System (INIS)

2000-01-01

This International Standard describes a precise and accurate analytical method for determining 1 mg to 5 mg of plutonium per millilitre in nitric acid solutions. The method is very selective for plutonium. It is suitable for the direct determination of plutonium in materials ranging from pure product solutions, to solutions of mixed nuclear materials with a uranium/plutonium ratio up to 20:1. However, potential application to the assay of plutonium in solutions of irradiated nuclear fuels and solutions of mixed nuclear materials with uranium/plutonium ratios of 20:1 to 33:1 has not yet been documented. The method recommends that the aliquot be weighed and that the titration burettes be calibrated gravimetrically in order to obtain adequate precision and accuracy. This does not preclude using any alternative technique which can be shown to give an equivalent accuracy. As the reproducibility of the reaction conditions is important to maintain good performance, extensive automatization of the procedure is beneficial

Spent fuel canister docking station

International Nuclear Information System (INIS)

Suikki, M.

2006-01-01

The working report for the spent fuel canister docking station presents a design for the operation and structure of the docking equipment located in the fuel handling cell for the spent fuel in the encapsulation plant. The report contains a description of the basic requirements for the docking station equipment and their implementation, the operation of the equipment, maintenance and a cost estimate. In the designing of the equipment all the problems related with the operation have been solved at the level of principle, nevertheless, detailed designing and the selection of final components have not yet been carried out. In case of defects and failures, solutions have been considered for postulated problems, and furthermore, the entire equipment was gone through by the means of systematic risk analysis (PFMEA). During the docking station designing we came across with needs to influence the structure of the actual disposal canister for spent nuclear fuel, too. Proposed changes for the structure of the steel lid fastening screw were included in the report. The report also contains a description of installation with the fuel handling cell structures. The purpose of the docking station for the fuel handling cell is to position and to seal the disposal canister for spent nuclear fuel into a penetration located on the cell floor and to provide suitable means for executing the loading of the disposal canister and the changing of atmosphere. The designed docking station consists of a docking ring, a covering hatch, a protective cone and an atmosphere-changing cap as well as the vacuum technology pertaining to the changing of atmosphere and the inert gas system. As far as the solutions are concerned, we have arrived at rather simple structures and most of the actuators of the system are situated outside of the actual fuel handling cell. When necessary, the equipment can also be used for the dismantling of a faulty disposal canister, cut from its upper end by machining. The

HTGR fuel cycle

International Nuclear Information System (INIS)

1987-08-01

In the spring of 1987, the HTGR fuel cycle project has been existing for ten years, and for this reason a status seminar has been held on May 12, 1987 in the Juelich Nuclear Research Center, that gathered the participants in this project for a discussion on the state of the art in HTGR fuel element development, graphite development, and waste management. The papers present an overview of work performed so far and an outlook on future tasks and goals, and on taking stock one can say that the project has been very successful so far: The HTGR fuel element now available meets highest requirements and forms the basis of today's HTGR safety philosophy; research work on graphite behaviour in a high-temperature reactor has led to complete knowledge of the temperature or neutron-induced effects, and with the concept of direct ultimate waste disposal, the waste management problem has found a feasible solution. (orig./GL) [de

Simulations of the Thermodynamic and Diffusion Properties of Actinide Oxide Fuel Materials

International Nuclear Information System (INIS)

Becker, Udo

2013-01-01

Spent nuclear fuel from commercial reactors is comprised of 95-99 percent UO 2 and 1-5 percent fission products and transuranic elements. Certain actinides and fission products are of particular interest in terms of fuel stability, which affects reprocessing and waste materials. The transuranics found in spent nuclear fuels are Np, Pu, Am, and Cm, some of which have long half- lives (e.g., 2.1 million years for 237 Np). These actinides can be separated and recycled into new fuel matrices, thereby reducing the nuclear waste inventory. Oxides of these actinides are isostructural with UO 2 , and are expected to form solid solutions. This project will use computational techniques to conduct a comprehensive study on thermodynamic properties of actinide-oxide solid solutions. The goals of this project are to: Determine the temperature-dependent mixing properties of actinide-oxide fuels; Validate computational methods by comparing results with experimental results; Expand research scope to complex (ternary and quaternary) mixed actinide oxide fuels. After deriving phase diagrams and the stability of solid solutions as a function of temperature and pressure, the project team will determine whether potential phase separations or ordered phases can actually occur by studying diffusion of cations and the kinetics of potential phase separations or ordered phases. In addition, the team will investigate the diffusion of fission product gases that can also have a significant influence on fuel stability. Once the system has been established for binary solid solutions of Th, U, Np, and Pu oxides, the methodology can be quickly applied to new compositions that apply to ternaries and quaternaries, higher actinides (Am, Cm), burnable poisons (B, Gd, Hf), and fission products (Cs, Sr, Tc) to improve reactivity

Parameters affecting level measurement interpretation of nuclear fuel solutions

International Nuclear Information System (INIS)

Hunt, B.A.; Landat, D.A.

1999-01-01

This paper describes a level measurement technique commonly used in the measurement of radioactive liquids and equipment utilised by the inspectors for safeguards purposes. Some of the influencing parameters affecting the measurement results by this technique are characterised. An essential requisite for successful process operations in chemical facilities involving liquids generally require some physical measurements to be made in-line for both process and quality control in order to achieve the necessary final product specifications . In nuclear fuel reprocessing facilities, the same objectives apply coupled however with an additional requirement of achieving nuclear material accountancy and control. In view of the strategic importance of some of the process vessels in nuclear facilities, accountancy has to be supported by volume and density measurements of low uncertainty. Inspectors therefore require instruments which are at the very least as good as or better than operator's equipment. The classical measurement technique and most widely applied for process liquids in nuclear installations is the bubbler probe or dip-tube technique. Here a regulated flow of air passes through tubes inserted to various depths into the vessel and pressure readings are measured which are a function of the presence of liquid height and density of solution in the tank. These readings, taken together with a pre-determined calibration curve are sufficient for the volume and amount of liquor in a tank to be quantified. All measurement equipment and instrumentation are long distances from the tank environment. The key physical parameter to measure at this location is therefore pressure. Equipment designed developed, commissioned and tested in the tank measurement facilities at Ispra and in nuclear installations in Europe, Japan and the USA, house digital pressure transducer modules with manufacture's declared features of better than 0.01% accuracy and long term stability of 0.01% full

hydrogel membrane as electrolyte for direct borohydride fuel cells

Indian Academy of Sciences (India)

A direct borohydride fuel cell (DBFC) employing a poly (vinyl alcohol) hydrogel membrane electrolyte (PHME) is reported. The DBFC employs an AB5 Misch metal alloy as anode and a goldplated stainless steel mesh as cathode in conjunction with aqueous alkaline solution of sodium borohydride as fuel and aqueous ...

Fuel element performance computer modelling

International Nuclear Information System (INIS)

Locke, D.H.

1978-01-01

The meeting was attended by 88 participants from 17 countries. Altogether 47 papers were presented. The majority of the presentations contained a description of the equations and solutions used to describe and evaluate some of the physical processes taking place in water reactor fuel pins under irradiation. At the same time, particular attention was paid to the ''bench marking'' of the codes wherein solutions arrived at for particular experiments are compared with the results at the experiments

PWR fuel physico chemistry. Improvements of the Sage code to compute thermochemical balance in PWR fuel

International Nuclear Information System (INIS)

Garcia, P.; Baron, D.; Piron, J.P.

1993-02-01

A physicochemical survey of high burnup fuel has been undertaken in the context of a 3-party action (CEA Cadarache - EDF/DER - FRAMATOME). One of the tasks involved consists in adapting the SAGE code for assessment of the thermochemical equilibria of fission products in solution in the fuel matrix. This paper describes the first stage of this task. Even if other improvements are planned, the oxid oxygen potentials are yet properly reproduced for the simulated burnup. (authors). 63 figs., 4 tabs., 41 refs

The buckling of fuel rods in transportation casks under hypothetical accident conditions

International Nuclear Information System (INIS)

Bjorkman, G.S.

2004-01-01

The buckling analysis of fuel rods during an end drop impact of a spent fuel transportation cask has traditionally been performed to demonstrate the structural integrity of the fuel rod cladding or the integrity of the fuel geometry in criticality evaluations following a cask drop event. The actual calculation of the fuel rod buckling load, however, has been the subject of some controversy, with estimates of the critical buckling load differing by as much as a factor of 5. Typically, in the buckling analysis of a fuel rod, assumptions are made regarding the percentage of fuel mass that is bonded to or participates with the cladding during the buckling process, with estimates ranging from 0 to 100%. The greater the percentage of fuel mass that is assumed to be bonded to the cladding the higher the inertia loads on the cladding, and, therefore, the lower the ''g'' value at which buckling occurs. Current published solutions do not consider displacement compatibility between the fuel and the cladding. By invoking displacement compatibility between the fuel column and the cladding column, this paper presents an exact solution for the buckling of fuel rods under inertia loading. The results show that the critical inertia load magnitude for the buckling of a fuel rod depends on the weight of the cladding and the total weight of the fuel, regardless of the percentage of fuel mass that is assumed to be attached to or participate with the cladding in the buckling process. Therefore, 100% of the fuel always participates in the buckling of a fuel rod under inertia loading

Expansion of capacity of spent fuel pools and associated problems

International Nuclear Information System (INIS)

Francisco, J.L. De; Lopez-Cotarelo, J.; Ramos, J.M.

1978-01-01

Expanding the spent fuel storage pool capacity is a good solution for utilities facing the current shortage in fuel reprocessing capacity. The problems more likely to be found when expanding a spent fuel storage facility by using high density storage racks are reviewed. Basically three types of problems arise: 1) Problems related with the characteristics of the new facility. 2) Problems related with the works of expansion. 3) Problems related with the long term storage of large quantities of spent fuel. (author)

Current state of knowledge in radiolysis effects on spent fuel corrosion

International Nuclear Information System (INIS)

Christensen, H.; Sunder, S.

1998-09-01

Literature data on the effect of water radiolysis products on spent fuel oxidation and dissolution have been reviewed. Effects of γ-radiolysis, α-radiolysis and dissolved O 2 or H 2 O 2 in unirradiated solutions have been discussed separately. Also the effect of carbonate in γ-irradiated solutions and radiolysis effects on leaching of spent fuels have been reviewed. In addition a radiolysis model for calculation of corrosion rates of UO 2 , presented previously, has been discussed. The model has been shown to give a good agreement between calculated and measured corrosion rates in the case of γ-radiolysis and in unirradiated solutions of dissolved oxygen or hydrogen peroxide. The model has failed to predict the results of α-radiolysis. In a recent study it was shown that the model gave a good agreement with measured corrosion rates of spent fuel exposed in deionized water

Cermet fuel for fast reactor – Fabrication and characterization

Energy Technology Data Exchange (ETDEWEB)

Mishra, Sudhir, E-mail: sudhir@barc.gov.in [Radiometallurgy Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Kutty, P.S.; Kutty, T.R.G. [Radiometallurgy Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Das, Shantanu [Uranium Extraction Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Dey, G.K. [Materials Science Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Kumar, Arun [Radiometallurgy Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

2013-11-15

(U, Pu)O{sub 2} ceramic fuel is the well-established fuel for the fast reactors and (U, Pu, Zr) metallic fuel is the future fuel. Both the fuels have their own merits and demerits. Optimal solution may lie in opting for a fuel which combines the favorable features of both fuel systems. The choice may be the use of cermet fuel which can be either (U, PuO{sub 2}) or (Enriched U, UO{sub 2}). In the present study, attempt has been made to fabricate (Natural U, UO{sub 2}) cermet fuel by powder metallurgy route. Characterization of the fuel has been carried out using dilatometer, differential thermal analyzer, X-ray diffractometer, and Scanning Electron Microscope. The results show a high solidus temperature, high thermal expansion, presence of porosities, etc. in the fuel. The thermal conductivity of the fuel has also been measured. X-ray diffraction study on the fuel compact reveals presence of α U and UO{sub 2} phases in the matrix of the fuel.

Compact nuclear fuel storage

International Nuclear Information System (INIS)

Kiselev, V.V.; Churakov, Yu.A.; Danchenko, Yu.V.; Bylkin, B.K.; Tsvetkov, S.V.

1983-01-01

Different constructions of racks for compact storage of spent fuel assemblies (FA) in ''coolin''g pools (CP) of NPPs with the BWR and PWR type reactors are described. Problems concerning nuclear and radiation safety and provision of necessary thermal conditions arising in such rack design are discussed. It is concluded that the problem of prolonged fuel storage at NPPs became Very actual for many countries because of retapdation of the rates of fuel reprocessing centers building. Application of compact storage racks is a promising solution of the problem of intermediate FA storage at NPPs. Such racks of stainless boron steel and with neutron absorbers in the from of boron carbide panels enable to increase the capacity of the present CP 2-2.6 times, and the period of FA storage in them up to 5-10 years

Recent developments in spent fuel management in Norway - 59260

International Nuclear Information System (INIS)

Bennett, Peter J.; Oberlaender, Barbara C.

2012-01-01

Spent Nuclear Fuel (SNF) in Norway has arisen from irradiation of fuel in the NORA, Jeep I and Jeep II reactors at Kjeller, and in the Heavy Boiling Water Reactor (HBWR) in Halden. In total there is some 16 tonnes of SNF, with 12 tons of aluminium-clad fuel, of which 10 tonnes is metallic uranium fuel and the remainder oxide (UO 2 ). The portion of this fuel that is similar to commercial fuel (UO 2 clad in Zircaloy) may be suitable for direct disposal on the Swedish model or in other repository designs. However, metallic uranium and/or fuels clad in aluminium are chemically reactive and there would be risks associated with direct disposal. Two committees were established by the Government of Norway in January 2009 to make recommendations for the interim storage and final disposal of spent fuel in Norway. The Technical Committee on Storage and Disposal of Metallic Uranium Fuel and Al-clad Fuels was formed with the mandate to recommend treatment (i.e. conditioning) options for metallic uranium fuel and aluminium-clad fuel to render them stable for long term storage and disposal. This committee, whose members were drawn from the nuclear industry, reported in January 2010, and recommended commercial reprocessing as the best option for these fuels. The Phase-2 committee, which in part based its work on the work of previous committees and on the report of the Technical Committee, had the mandate to find the most suitable technical solution and localisation for intermediate storage for spent nuclear fuel and long-lived waste. The membership of this committee was chosen to represent a broad cross section of stakeholders. The committee evaluated different solutions and their associated costs, and recommended one of the options. The committee's report published in early 2011. This paper summarises the conclusions of the two committees, and thereby illustrates the steps taken by one country to formulate a strategy for the long-term management of its SNF. (authors)

Optimization programs for reactor core fuel loading exhibiting reduced neutron leakage

International Nuclear Information System (INIS)

Darilek, P.

1991-01-01

The program MAXIM was developed for the optimization of the fuel loading of WWER-440 reactors. It enables the reactor core reactivity to be maximized by modifying the arrangement of the fuel assemblies. The procedure is divided into three steps. The first step includes the passage from the three-dimensional model of the reactor core to the two-dimensional model. In the second step, the solution to the problem is sought assuming that the multiplying properties, or the reactivity in the zones of the core, vary continuously. In the third step, parameters of actual fuel assemblies are inserted in the ''continuous'' solution obtained. Combined with the program PROPAL for a detailed refinement of the loading, the program MAXIM forms a basis for the development of programs for the optimization of fuel loading with burnable poisons. (Z.M.). 16 refs

A microfluidic-structured flow field for passive direct methanol fuel cells operating with highly concentrated fuels

International Nuclear Information System (INIS)

Wu, Q X; Zhao, T S; Chen, R; Yang, W W

2010-01-01

Conventional direct methanol fuel cells (DMFCs) have to operate with excessively diluted methanol solutions to limit methanol crossover and its detrimental consequences. Operation with such diluted methanol solutions not only results in a significant penalty in the specific energy of the power pack, limiting the runtime of this type of fuel cell, but also lowers the cell performance and operating stability. In this paper, a microfluidic-structured anode flow field for passive DMFCs with neither liquid pumps nor gas compressors/blowers is developed. This flow field consists of plural micro flow passages. Taking advantage of the liquid methanol and gas CO 2 two-phase counter flow, the unique fluidic structure enables the formation of a liquid–gas meniscus in each flow passage. The evaporation from the small meniscus in each flow passage can lead to an extremely large interfacial mass-transfer resistance, creating a bottleneck of methanol delivery to the anode CL. The fuel cell tests show that the innovative flow field allows passive DMFCs to achieve good cell performance with a methanol concentration as high as 18.0 M, increasing the specific energy of the DMFC system by about five times compared with conventional designs.

Systematic study on Thorium fuel

International Nuclear Information System (INIS)

Shibata, Toshikazu; Kimura, Itsuro; Iwata, Shiro; Furuya, Hirotaka; Suzuki, Susumu.

1988-01-01

Introduced is the activities of the Joint Research Project Team on Thorium Fuel organized by mainly university researchers in Japan and supported by the Ministry of Education, Science and Culture for seven years since 1980. Four major groups were organized; (1) nuclear data, reactor physics and design, (2) nuclear fuel, (3) down stream and (4) biological effects of thorium. The first group covered measurements and analysis on nuclear data of thorium related nuclides, experiment and analysis on nuclear characteristics of thorium containing cores, basic engineering on a thorium molten salt reactor, and designs of several types of reactors. Fabrication and irradiation tests of thorium oxide fuel, and basic studies on new type thorium fuels (e.g. carbide and nitride) were studied by the second group. The third group covered the use of solutions in reprocessing of spent fuel, behavior of fission products, immobilization of high level radioactive waste, and continuous reprocessing for a molten salt reactor. The fourth group performed the trace study for patients who had been intravascularly injected with thorotrast for diagnosis of war injuries during the Second World War. (author)

Management of irradiated CANDU fuel

International Nuclear Information System (INIS)

Lupien, Mario

1985-01-01

The nuclear industry, like any other industrial activity, generates waste and, since these radioactive products are known to be hazardous both to man and his natural environment, they are subject to stringent controls. The irradiated fuel is also highly radioactive and remains so for thousands of years. It is estimated that by the year 2000, nuclear reactors in Canada alone will have produced some 50 Gg of radioactive fuel which is stored at the nuclear plant site itself. The nuclear industry plays a leading role in the research and development effort to find suitable waste-management methods. Its R and D programs cover many scientific fields, including chemistry, and therefore demand a considerable amount of coordination. The knowledge acquired in this multidisciplinary context should form a basis for solving many of today's industrial-waste problems. This paper describes the various stages in the long management process. In the medium term, the irradiated fuel will be stored in surface installations but the long-term solution proposed is to emplace the used fuel or the fuel recycle waste deep underground in a stable geologic formation

Mixtures of methanol and 2-propanol as a potential fuel for direct alcohol fuel cells

Directory of Open Access Journals (Sweden)

S. LJ. GOJKOVIC

2007-12-01

Full Text Available The electrochemical oxidation of methanol, 2-propanol, and their mixtures was investigated on a Pt/C thin film electrode in acid solution. It was confirmed that the oxidation of 2-propanol commences at less positive potentials than that of methanol and exhibits significantly higher oxidation current densities at low potentials. When both methanol and 2-propanol were present in the solution, the onset of the oxidation current was the same as for the oxidation of pure 2-propanol. Although both alcohols inhibit the oxidation reaction of each other to a certain extent, steady-state polarization measurements showed that their mixture provides higher current densities than single alcohols over the entire potential region from the hydrogen region to oxide formation on the Pt surface. This implies that the addition of 2-propanol into the fuel may extend the operational range of direct methanol fuel cells.

Management and storage of spent research reactor fuel within the Federal Republic of Germany

International Nuclear Information System (INIS)

Krull, W.

1996-01-01

Research reactors in the Federal Republic of Germany and their needs for the interim storage of spent nuclear fuel are described. Existing long-term interim storage facilities are described. Special licensing and legal restrictions imposed by the German Atomic Energy Act are outlined. Possible final solutions for the back end of the nuclear fuel cycle for research reactors, including reprocessing in the United Kingdom or France, return of US-origin fuel and a home-grown German solution are discussed. (author). 2 refs, 5 figs, 4 tabs

21st century energy solutions. Coal and Power Systems FY2001 program briefing

International Nuclear Information System (INIS)

None

2001-01-01

The continued strength of American's economy depends on the availability of affordable energy, which has long been provided by the Nations rich supplies of fossil fuels. Forecasts indicate that fossil fuels will continue to meet much of the demand for economical electricity and transportation fuels for decades to come. It is projected that natural gas, oil, and coal will supply nearly 90% of US energy in 2020, with coal fueling around 50% of the electricity. It is essential to develop ways to achieve the objectives for a cleaner environment while using these low-cost, high-value fuels. A national commitment to improved technologies-for use in the US and abroad-is the solution. The Coal and Power Systems program is responding to this commitment by offering energy solutions to advance the clean, efficient, and affordable use of the Nations abundant fossil fuel resources. These solutions include: (1) Vision 21-A multi-product, pollution-free energy plant-producing electricity, fuels, and/or industry heat-could extract 80% or more of the energy value of coal and 85% or more of the energy value of natural gas; (2) Central Power Systems-Breakthrough turbines and revolutionary new gasification technologies that burn less coal and gas to obtain energy, while reducing emissions; (3) Distributed Generation-Fuel cell technology providing highly efficient, clean modular power; (4) Fuels-The coproduction of coal-derived transportation fuels and power from gasification-based technology; (5) Carbon Sequestration-Capturing greenhouse gases from the exhaust gases of combustion or other sources, or from the atmosphere itself, and storing them for centuries or recycling them into useful products; and (6) Advanced Research-Going beyond conventional thinking in the areas of computational science, biotechnology, and advanced materials

Results from Tight and Loose Coupled Multiphysics in Nuclear Fuels Performance Simulations using BISON

Energy Technology Data Exchange (ETDEWEB)

S. R. Novascone; B. W. Spencer; D. Andrs; R. L. Williamson; J. D. Hales; D. M. Perez

2013-05-01

The behavior of nuclear fuel in the reactor environment is affected by multiple physics, most notably heat conduction and solid mechanics, which can have a strong influence on each other. To provide credible solutions, a fuel performance simulation code must have the ability to obtain solutions for each of the physics, including coupling between them. Solution strategies for solving systems of coupled equations can be categorized as loosely-coupled, where the individual physics are solved separately, keeping the solutions for the other physics fixed at each iteration, or tightly coupled, where the nonlinear solver simultaneously drives down the residual for each physics, taking into account the coupling between the physics in each nonlinear iteration. In this paper, we compare the performance of loosely and tightly coupled solution algorithms for thermomechanical problems involving coupled thermal and mechanical contact, which is a primary source of interdependence between thermal and mechanical solutions in fuel performance models. The results indicate that loosely-coupled simulations require significantly more nonlinear iterations, and may lead to convergence trouble when the thermal conductivity of the gap is too small. We also apply the tightly coupled solution strategy to a nuclear fuel simulation of an experiment in a test reactor. Studying the results from these simulations indicates that perhaps convergence for either approach may be problem dependent, i.e., there may be problems for which a loose coupled approach converges, where tightly coupled won’t converge and vice versa.

Results from tight and loose coupled multiphysics in nuclear fuels performance simulations using BISON

International Nuclear Information System (INIS)

Novascone, S. R.; Spencer, B. W.; Andrs, D.; Williamson, R. L.; Hales, J. D.; Perez, D. M.

2013-01-01

The behavior of nuclear fuel in the reactor environment is affected by multiple physics, most notably heat conduction and solid mechanics, which can have a strong influence on each other. To provide credible solutions, a fuel performance simulation code must have the ability to obtain solutions for each of the physics, including coupling between them. Solution strategies for solving systems of coupled equations can be categorized as loosely-coupled, where the individual physics are solved separately, keeping the solutions for the other physics fixed at each iteration, or tightly coupled, where the nonlinear solver simultaneously drives down the residual for each physics, taking into account the coupling between the physics in each nonlinear iteration. In this paper, we compare the performance of loosely and tightly coupled solution algorithms for thermomechanical problems involving coupled thermal and mechanical contact, which is a primary source of interdependence between thermal and mechanical solutions in fuel performance models. The results indicate that loosely-coupled simulations require significantly more nonlinear iterations, and may lead to convergence trouble when the thermal conductivity of the gap is too small. We also apply the tightly coupled solution strategy to a nuclear fuel simulation of an experiment in a test reactor. Studying the results from these simulations indicates that perhaps convergence for either approach may be problem dependent, i.e., there may be problems for which a loose coupled approach converges, where tightly coupled won't converge and vice versa. (authors)

Efficient solutions from HVAC to offgrid

International Nuclear Information System (INIS)

Anon.

2014-01-01

Rio Tinto and Ingenero recently announced that agreement had been reached for the development of the Weipa Solar Photovoltaic Project in Queensland. First Solar will leverage its expertise in utility-scale grid integration and plant control systems to offer a FuelSmart solution that provides maximum fuel savings while maintaining system reliability. Combined with Ingenero's design and integration experience, the project will generate electricity for Rio Tinto Alcan's Weipa bauxite mine, processing facilities and township on the Western Cape York Peninsula

Siemens fuel gasification technology - solutions and developments

Energy Technology Data Exchange (ETDEWEB)

Hannemann, F.; Schingnitz, M.; Schmid, C. [Siemens Fuel Gasification Technology GmbH, Freiberg (Germany)

2007-07-01

In 2006, Siemens Power Generation Group acquired the GSP Gasification technology, and renamed it SFGT. The presentation reviews the technology and provides an update on current projects. The future plans for the development of the technology based on extensive experience and comprehensive development work gathered over many years and proven in a number of gasification plants is covered. SFGT operates, at its Freiberg facility, a 5 MWth pilot plant which was built to test prototype designs and to determine process conditions for various feed streams. An overview is given of the results of tests completed on a wide range of carbonaceous materials including all types of solid fuels from lignite to anthracite, as well as brown coal, oil, sludge or biomass, and low-temperature coke or petcoke. The technical focus of the paper is on the unique design features such as the cooling screen and alternative refractory lining, as well as the dense flow feeding system that allows the preferable use of lignite applications.

In-Core Fuel Managements for PWRs: Investigation on solution for optimal utilization of PWR fuel through the use of fuel assemblies with differently enriched {sup 235}U fuel pins

Energy Technology Data Exchange (ETDEWEB)

Caprioli, Sara

2004-04-01

A possibility for more efficient use of the nuclear fuel in a pressurized water reactor is investigated. The alternative proposed here consists of the implementation of PWR fuel assemblies with differently enriched {sup 235}U fuel pins. This possibility is examined in comparison with the standard assembly design. The comparison is performed both in terms of single assembly performance and in the terms of nuclear reactor core performance and fuel utility. For the evaluation of the actual performance of the new assembly types, 5 operated fuel core sequences of R3 (Ringhals' third unit), for the period 1999 - 2004 (cycles 17 - 21) were examined. For every cycle, the standard fresh fuel assemblies have been identified and taken as reference cases for the study of the new type of assemblies with differently enriched uranium rods. In every cycle, assemblies with and without burnable absorber are freshly loaded into the core. The axial enrichment distribution is kept uniform, allowing for a radial (planar) enrichment level distribution only. At an assembly level, it has been observed that the implementation of the alternative enrichment configuration can lead to lower and flatter internal peaking factor distribution with respect to the uniformly enriched reference assemblies. This can be achieved by limiting the enrichment levels distribution to a rather narrow range. The highest enrichment level chosen has the greatest impact on the power distribution of the assemblies. As it increases, the enrichment level drives the internal peaking factor to greater values than in the reference assemblies. Generally, the highest enrichment level that would allow an improvement in the power performance of the assembly lies between 3.95 w/o and 4.17 w/o. The highest possible enrichment level depends on the average enrichment of the overall assembly, which is kept constant to the average enrichment of the reference assemblies. The improvements that can be obtained at this level are

A higher order depletion perturbation theory with application to in-core fuel management optimization

International Nuclear Information System (INIS)

Kropaczek, D.J.; Turinsky, P.J.

1990-01-01

Perturbation techniques utilized in reactor analysis have recently been applied in the solution of the in-core nuclear fuel management optimization problem. The use of such methods is motivated by the need to evaluate many times over, the core physics characteristics of loading pattern solutions obtained through an optimization process, which is typically iterative. Perturbation theory provides an efficient alternative to the prohibitively expensive, repetitive solutions of the system few-group neutron diffusion equations required in solving the fuel placement problem. A primary concern in the use of such methods is the control of perturbation errors arising during the fuel shuffling process. First-order accurate models inevitably resort to undue restriction of fuel movement during the optimization process to control these errors. Higher order perturbation theory models have the potential to overcome such limitations, which may result in the identification of local versus global optima. An accurate, computationally efficient reactor physics model based on higher order perturbation theory and geared toward the needs of large-scale in-core fuel management optimization is presented in this paper

Spent fuel transportation problems

International Nuclear Information System (INIS)

Kondrat'ev, A.N.; Kosarev, Yu.A.; Yulikov, E.A.

1977-01-01

In this paper, problems of transportation of nuclear spent fuel to reprocessing plants are discussed. The solutions proposed are directed toward the achievement of the transportation as economic and safe as possible. The increase of the nuclear power plants number in the USSR and the great distances between these plants and the reprocessing plants involve an intensification of the spent fuel transportation. Higher burnup and holdup time reduction cause the necessity of more bulky casks. In this connection, the economic problems become still more important. One of the ways of the problem solution is the development of rational and cheap cask designs. Also, the enforcement in the world of the environmental and personnel health protection requires to increase the transportation reliability and safety. The paper summarizes safe transportation rules with clarifying the following questions: the increase of the transport unit quantity of the spent fuel; rational shipment organization that minimizes vehicle turnover cycle duration; development of the reliable calculation methods to determine strength, thermal conditions and nuclear safety of transport packaging as applied to the vehicles of high capacity; maximum unification of vehicles, calculation methods and documents; and cask testing on models and in pilot scale on specific test rigs to assure that they meet the international safe fuel shipment rules. Besides, some considerations on the choice and use of structural materials for casks are given, and problems of manufacturing such casks from uranium and lead are considered, as well as problems of the development of fireproof shells, control instrumentation, vehicles decontamination, etc. All the problems are considered from the point of view of normal and accidental shipment conditions. Conclusions are presented [ru

Radioactive waste management in a fuel reprocessing facility in fiscal 1982

International Nuclear Information System (INIS)

1984-01-01

In the fuel reprocessing facility of the Power Reactor and Nuclear Fuel Development Corporation, radioactive gaseous and liquid waste are released not exceeding the respective permissible levels. Radioactive concentrated solutions are stored at the site. Radioactive solid waste are stored appropriately at the site. In fiscal 1982, the released quantities of radioactive gaseous and liquid waste were both below the permissible levels. The results of radioactive waste management in the fuel reprocessing facility in fiscal 1982 are given in the tables: the released quantities of radioactive gaseous and liquid waste, the produced quantities of radioactive solid waste, and the stored quantities of radioactive concentrated solutions and of radioactive solid waste as of the end of fiscal 1982. (Mori, K.)

Spent fuel reprocessing method

International Nuclear Information System (INIS)

Shoji, Hirokazu; Mizuguchi, Koji; Kobayashi, Tsuguyuki.

1996-01-01

Spent oxide fuels containing oxides of uranium and transuranium elements are dismantled and sheared, then oxide fuels are reduced into metals of uranium and transuranium elements in a molten salt with or without mechanical removal of coatings. The reduced metals of uranium and transuranium elements and the molten salts are subjected to phase separation. From the metals of uranium and transuranium elements subjected to phase separation, uranium is separated to a solid cathode and transuranium elements are separated to a cadmium cathode by an electrolytic method. Molten salts deposited together with uranium to the solid cathode, and uranium and transuranium elements deposited to the cadmium cathode are distilled to remove deposited molten salts and cadmium. As a result, TRU oxides (solid) such as UO 2 , Pu 2 in spent fuels can be reduced to U and TRU by a high temperature metallurgical method not using an aqueous solution to separate them in the form of metal from other ingredients, and further, metal fuels can be obtained through an injection molding step depending on the purpose. (N.H.)

Solution treatment of fast reactor claddings

International Nuclear Information System (INIS)

Miura, Makoto; Nagaki, Hiroshi; Koyama, Masahiro

1974-01-01

The fuel cladding tubes for Joyo (experimental FBR) are required to be a material corresponding to AISI Type 316 and cold-rolled after solution treatment. It is necessary to have no precipitation of carbide and to make the grain size smaller than ASTM No.6. It is very difficult to obtain the fine grains without the precipitation, however. In this connection, the behavior of carbide solution at high temperature and the annealing behavior of the material cold-worked and solution-treated were studied. The following matters are described: the solid solubility line of AISI Type 316; the behavior of carbide at solution treatment temperature; and the annealing behavior of the cold-worked material. (Mori, K.)

A study for providing additional storage spaces to ET-RR-1 spent fuel

International Nuclear Information System (INIS)

El-Kady, A.; Ashoub, N.; Saleh, H.G.

1995-01-01

The ET-RR-1 reactor spent fuel storage pool is a trapezoidal aluminum tank concrete shield and of capacity 10 m 3 . It can hold up to 60 fuel assemblies. The long operation history of the ET-RR-1 reactor resulted in a partially filled spent fuel storage with the remaining spaces not enough to host a complete load from the reactor. This work have been initiated to evaluate possible alternative solutions for providing additional storage spaces to host the available EK-10 fuel elements after irradiation and any foreseen fuel in case of reactor upgrading. Several alternate solutions have been reviewed and decision on the most suitable one is under study. These studies include criticality calculation of some suggested alternatives like reracking the present spent fuel storage pool and double tiering by the addition of a second level storage rack above the existing rack. The two levels may have different factor. Criticality calculation of the double tiering possible accident was also studied. (author)

Regional disposal, a feasible solution for Romania

International Nuclear Information System (INIS)

Radu, Maria

2004-01-01

Almost every country that exploits or builds nuclear power plants is engaged in its own research or international cooperation programs aiming at identification of optimal solutions of closing the fuel cycle and finding feasible technologies for final disposal of spent fuel and high-level wastes resulting from reprocessing. The general trend that manifests in these countries is to manage on their own territories the final disposal while considering the possibility of regional arrangements for common disposal. But this latter alternative has not been definitively analyzed and decided upon. Hence, European Union and IAEA look for solutions of long term (of the order of hundreds years) for the final disposal, particularly within regional facilities. Multinational repositories where disposal of high-level wastes or spent fuel should appear as a paid specialized servicing, where the operation technical conditions would be well established, as secure from nuclear safety and physical point of view, under the provisions of safeguards agreements, are still under consideration. No matter of the option which will be chosen, closing the nuclear cycle and ensuring a final disposal facility for radioactive wastes are compulsory tasks and issues with many aspects in common (establishing a site hosted by stable deep geological formations, protection by engineered barriers to prevent dispersion of radioactive products into the environment, long term analyses, etc). In this circumstances, having in mind that no other variant appears to be achievable before 2020-2050, intermediate term storage appears as compulsory a solution in developing the fuel cycle both world wide and in Romania, As early as in the first half of 2003 at Cernavoda, the Intermediate Storage for Spent Fuel (DICA) was commissioned. This is a facility founded for the first time in Romania aiming at closing the fuel cycle. The paper presents the current issues and the results obtained so far within the frame of

Nuclear-powered pacemaker fuel cladding study

International Nuclear Information System (INIS)

Shoup, R.L.

1976-07-01

The fabrication of fuel capsules with refractory metal and alloy clads used in nuclear-powered cardiac pacemakers precludes the expedient dissolution of the clad in inorganic acid solutions. An experiment to measure penetration rates of acids on commonly used fuel pellet clads indicated that it is not impossible, but that it would be very difficult to dissolve the multiple cladding. This work was performed because of a suggestion that a 238 PuO 2 -powered pacemaker could be transformed into a terrorism weapon

Current developments of fuel fabrication technologies at the plutonium fuel production facility, PFPF

International Nuclear Information System (INIS)

Asakura, K.; Aono, S.; Yamaguchi, T.; Deguchi, M.

2000-01-01

The Japan Nuclear Cycle Development Institute, JNC, designed, constructed and has operated the Plutonium Fuel Production Facility, PFPF, at the JNC Tokai Works to supply MOX fuels to the proto-type Fast Breeder Reactor, FBR, 'MONJU' and the experimental FBR 'JOYO' with 5 tonMOX/year of fabrication capability. Reduction of personal radiation exposure to a large amount of plutonium is one of the most important subjects in the development of MOX fabrication facility on a large scale. As the solution of this issue, the PFPF has introduced automated and/or remote controlled equipment in conjunction with computer controlled operation scheme. The PFPF started its operation in 1988 with JOYO reload fuel fabrication and has demonstrated MOX fuel fabrication on a large scale through JOYO and MONJU fuel fabrication for this decade. Through these operations, it has become obvious that several numbers of equipment initially installed in the PFPF need improvements in their performance and maintenance for commercial utilization of plutonium in the future. Furthermore, fuel fabrication of low density MOX pellets adopted in the MONJU fuel required a complete inspection because of difficulties in pellet fabrication compared with high density pellet for JOYO. This paper describes new pressing equipment with a powder recovery system, and pellet finishing and inspection equipment which has multiple functions, such as grinding measurements of outer diameter and density, and inspection of appearance to improve efficiency in the pellet finishing and inspection steps. Another development of technology concerning an annular pellet and an innovative process for MOX fuel fabrication are also described in this paper. (author)

Recent Advances in High-Performance Direct Methanol Fuel Cells

Science.gov (United States)

Narayanan, S. R.; Chun, W.; Valdez, T. I.; Jeffries-Nakamura, B.; Frank, H.; Surumpudi, S.; Halpert, G.; Kosek, J.; Cropley, C.; La Conti, A. B.;

Agro-fuels: southern impacts; Agrocarburants: impacts au Sud

Energy Technology Data Exchange (ETDEWEB)

Duterme, B.

2011-07-01

At a time of controversies about global warming, agro-fuels production is often presented as a future solution for automotive fuels and as a new way of development for southern countries. However, in Asia, South America and Africa, it very often takes the form of huge mono-culture areas of sugar cane, palm oil and soy bean in the hands of multinational companies of the agriculture and food industry. The consequences of these land, social and environmental impacts in Southern countries is an increase of disequilibria and a threat for the diet of local populations by changing the appropriation of lands. Deforestation, private monopolization of lands, concentration of profits, soils and water pollution, biodiversity impoverishment, exploitation of vulnerable manpower, populations migration, violation of human rights are today the consequences of mass production of agro-fuels in Southern countries. To what conditions a fair re-appropriation and a sustainable development of agro-fuels production and consumption is foreseeable? The solutions require a re-shaping of economical and agricultural politics. The book gathers testimonies and analyses from specialists who have evaluated locally the consequences of these energy choices. (J.S.)

Fuel options for public bus fleets in Sweden

OpenAIRE

Xylia, Maria; Silveira, Semida

2015-01-01

The Swedish public transport sector has defined two major targets, i.e., to run 90% of the total vehicle kilometers of the fleet on non-fossil fuels and double the volume of travel via public transport by 2020, increasing the share of public transport in relation to the total personal transport in the country . The f3 report Fuel options for public bus fleets in Sweden highlights the challenges and solutions encountered, particularly when it comes to the adoption of renewable fuels in the reg...

Spent nuclear fuel storage - Basic concept

International Nuclear Information System (INIS)

Krempel, Ascanio; Santos, Cicero D. Pacifici dos; Sato, Heitor Hitoshi; Magalhaes, Leonardo de

2009-01-01

According to the procedures adopted in others countries in the world, the spent nuclear fuel elements burned to produce electrical energy in the Brazilian Nuclear Power Plant of Angra do Reis, Central Nuclear Almirante Alvaro Alberto - CNAAA will be stored for a long time. Such procedure will allow the next generation to decide how they will handle those materials. In the future, the reprocessing of the nuclear fuel assemblies could be a good solution in order to have additional energy resource and also to decrease the volume of discarded materials. This decision will be done in the future according to the new studies and investigations that are being studied around the world. The present proposal to handle the nuclear spent fuel is to storage it for a long period of time, under institutional control. Therefore, the aim of this paper is to introduce a proposal of a basic concept of spent fuel storage, which involves the construction of a new storage building at site, in order to increase the present storage capacity of spent fuel assemblies in CNAAA installation; the concept of the spent fuel transportation casks that will transfer the spent fuel assemblies from the power plants to the Spent Fuel Complementary Storage Building and later on from this building to the Long Term Intermediate Storage of Spent Fuel; the concept of the spent fuel canister and finally the basic concept of the spent fuel long term storage. (author)

Used mixed oxide fuel reprocessing at RT-1 plant

Energy Technology Data Exchange (ETDEWEB)

Kolupaev, D.; Logunov, M.; Mashkin, A.; Bugrov, K.; Korchenkin, K. [FSUE PA ' Mayak' , 30, Lenins str, Ozersk, 460065 (Russian Federation); Shadrin, A.; Dvoeglazov, K. [ITCP ' PRORYV' , 2/8 Malaya Krasmoselskay str, Moscow, 107140 (Russian Federation)

2016-07-01

Reprocessing of the mixed uranium-plutonium spent nuclear fuel of the BN-600 reactor was performed at the RT-1 plant twice, in 2012 and 2014. In total, 8 fuel assemblies with a burn-up from 73 to 89 GW day/t and the cooling time from 17 to 21 years were reprocessed. The reprocessing included the stages of dissolution, clarification, extraction separation of U and Pu with purification from the fission products, refining of uranium and plutonium at the relevant refining cycles. Dissolution of the fuel composition of MOX used nuclear fuel (UNF) in nitric acid solutions in the presence of fluoride ion has occurred with the full transfer of actinides into solution. Due to the high content of Pu extraction separation of U and Pu was carried out on a nuclear-safe equipment designed for the reprocessing of highly enriched U spent nuclear fuel and Pu refining. Technological processes of extraction, separation and refining of actinides proceeded without deviations from the normal mode. The output flow of the extraction outlets in their compositions corresponded to the regulatory norms and remained at the level of the compositions of the streams resulting from the reprocessing of fuel types typical for the RT-1 plant. No increased losses of Pu into waste have been registered during the reprocessing of BN-600 MOX UNF an compare with VVER-440 uranium UNF reprocessing. (authors)

Spent LWR fuel-storage costs

International Nuclear Information System (INIS)

Clark, H.J.

1981-01-01

Expanded use of existing storage basins is clearly the most economic solution to the spent fuel storage problem. The use of high-density racks followed by fuel disassembly and rod storage is an order of magnitude cheaper than building new facilities adjacent to the reactor. The choice of a new storage facility is not as obvious; however, if the timing of expenditures and risk allowance are to be considered, then modular concepts such as silos, drywells, and storage casks may cost less than water basins and air-cooled vaults. A comparison of the costs of the various storage techniques without allowances for timing or risk is shown. The impact of allowances for discounting and early resumption of reprocessing is also shown. Economics is not the only issue to be considered in selecting a storage facility. The licensing, environmental impact, timing, and social responses must also be considered. Each utility must assess all of these issues for their particular reactors before the best storage solution can be selected

Spent fuel transport in fuel cycle

International Nuclear Information System (INIS)

Labrousse, M.

1977-01-01

The transport of radioactive substances is a minor part of the fuel cycle because the quantities of matter involved are very small. However the length and complexity of the cycle, the weight of the packing, the respective distances between stations, enrichment plants and reprocessing plants are such that the problem is not negligible. In addition these transports have considerable psychological importance. The most interesting is spent fuel transport which requires exceptionally efficient packaging, especially where thermal and mechanical resistance are concerned. To meet the safety criteria necessary for the protection of both public and users it was decided to use the maximum capacity consistent with rail transport and to avoid coolant fluids under pressure. Since no single type of packing is suitable for all existing stations an effort has been made to standardise handling accessories, and future trands are towards maximum automation. A discussion on the various technical solutions available for the construction of these packing systems is followed by a description of those used for the two types of packaging ordered by COGEMA [fr

Sogin enriched uranium extraction (EUREX) plant spent fuel pool cleaning and decontamination utilizing the Smart Safe solution

International Nuclear Information System (INIS)

Denton, M.S.; Gili, M.; Nasta, M.; Quintiliani, R.; Caccia, G.; Botzen, W.; Forrester, K.

2009-01-01

SOGIN's EUREX facility in Italy was developed as a pilot plant functional testing laboratory for spent fuel reprocessing. This facility was operated successfully for many years since 1970 and was eventually shutdown consistent with Italy's suspension of all nuclear operations. At the time of suspension, the EUREX facility still had spent nuclear fuel assemblies in storage from a nearby PWR. Other fuel assemblies from an Italian AGR had remained stored in the spent fuel pool for the 20 years or so waiting for removal and reprocessing abroad. Being Magnox fuel elements, their recovery for the transport produced a huge amount of sludge in the pool. During this time, sediment, dirt, corrosion products, fuel cladding, etc. has collected within the fuel pool as a crud layer dispersed throughout. Most of this crud has accumulated on the horizontal surfaces of the pool and fuel element assemblies, while some remains as a suspended colloidal material. Furthermore many other contaminated metal components, used during the operation years, where still inside the pool. Due to a pool leak discovered in 2006, SOGIN speeded up its pool decommissioning program, making also available the transfer of the spent fuel to a nearby interim repository, with the goal to completely drain the pool in the shortest period of time. In order for SOGIN to successfully transfer the fuel assemblies from their current storage basket locations to the spent fuel transfer cask, the bulk of the crud needed to be removed. This cleanup operation was deemed necessary to minimize the suspension of contamination in the water during underwater handling operations. This would reduce the decontamination efforts on the transfer cask upon removal, once loaded with the spent fuel, and enhance safety by reducing potential underwater visibility issues. The operations were completed in July 2008 with the release to the environment of the pool water, thoroughly purified and without any relevant radiological impact. The

Alternate Fuels for Use in Commercial Aircraft

Science.gov (United States)

Daggett, David L.; Hendricks, Robert C.; Walther, Rainer; Corporan, Edwin

2008-01-01

The engine and aircraft Research and Development (R&D) communities have been investigating alternative fueling in near-term, midterm, and far-term aircraft. A drop in jet fuel replacement, consisting of a kerosene (Jet-A) and synthetic fuel blend, will be possible for use in existing and near-term aircraft. Future midterm aircraft may use a biojet and synthetic fuel blend in ultra-efficient airplane designs. Future far-term engines and aircraft in 50-plus years may be specifically designed to use a low- or zero-carbon fuel. Synthetic jet fuels from coal, natural gas, or other hydrocarbon feedstocks are very similar in performance to conventional jet fuel, yet the additional CO2 produced during the manufacturing needs to be permanently sequestered. Biojet fuels need to be developed specifically for jet aircraft without displacing food production. Envisioned as midterm aircraft fuel, if the performance and cost liabilities can be overcome, biofuel blends with synthetic jet or Jet-A fuels have near-term potential in terms of global climatic concerns. Long-term solutions address dramatic emissions reductions through use of alternate aircraft fuels such as liquid hydrogen or liquid methane. Either of these new aircraft fuels will require an enormous change in infrastructure and thus engine and airplane design. Life-cycle environmental questions need to be addressed.

Development and manufacturing of tape casted, anode-supported solid oxide fuel cells; Entwicklung und Herstellung von foliengegossenen, anodengestuetzten Festoxidbrennstoffzellen

Energy Technology Data Exchange (ETDEWEB)

Schafbauer, Wolfgang

2010-07-01

Solid oxide fuel cells offer high potential in transforming the chemical energy of hydrogen or natural gas into electrical energy. Due to the high efficiency of fuel cells, lots of effort has been made in the improvement of net efficiency and in materials development during the last years. Recently, the introduction of high performance, low-cost production technologies become more and more important. At the Institute of Energy Research IEF-1 of Forschungszentrum Julich, standard SOFCs were processed by time and work consuming methods. On the way to market entrance, product costs have to be reduced drastically. The aim of this thesis is the introduction of a high efficient low-cost processing route for the SOFC manufacturing. Therefore, the well-known and well established shaping technology tape casting was used for generating the anode substrates. As the first goal of this approach, two different tape casting slurries were developed in order to get substrates in the thickness range from 300 to 500 {mu}m after sintering. After shaping of the substrates, sinter regimes for the different necessary coatings were adapted to the novel substrate types in order to obtain cells with high performance and strength. Therefore, the different coating technologies like screen printing and vacuum slip casting were used for cell manufacturing. The optimization of the different coating steps during cell manufacturing led to high performance SOFCs with a 10% higher power output compared to the Julich state-of-the-art SOFC. Additional experiments verified the workability of the novel tape cast substrates for the manufacturing of near-net-shape SOFC. Finally, the novel cell types based on tape cast substrates were assembled to stacks with up to ten repeating units. Stack tests showed identical performance and degradation compared to stacks containing state-of-the-art SOFCs. Thus, the complete lifetime circle of a SOFC starting from powder preparation to stack assembly has been

Reducing the fuel temperature for pressure-tube supercritical-water-cooled reactors and the effect of fuel burnup

Energy Technology Data Exchange (ETDEWEB)

Nichita, E., E-mail: eleodor.nichita@uoit.ca; Kovaltchouk, V., E-mail: vitali.kovaltchouk@uoit.ca

2015-12-15

Highlights: • Typical PT-SCWR fuel uses single-region pins consisting of a homogeneous mixture of ThO{sub 2} and PuO{sub 2}. • Using two regions (central for the ThO{sub 2} and peripheral for the PuO{sub 2}) reduces the fuel temperature. • Single-region-pin melting-to-average power ratio is 2.5 at 0.0 MW d/kg and 2.3 at 40 MW d/kg. • Two-region-pin melting-to-average power ratio is 36 at 0.0 MW d/kg and 10.5 at 40 MW d/kg. • Two-region-pin performance drops with burnup due to fissile-element buildup in the ThO{sub 2} region. - Abstract: The Pressure-Tube Supercritical-Water-Cooled Reactor (PT-SCWR) is one of the concepts under investigation by the Generation IV International Forum for its promise to deliver higher thermal efficiency than nuclear reactors currently in operation. The high coolant temperature (>625 K) and high linear power density employed by the PT-SCWR cause the fuel temperature to be fairly high, leading to a reduced margin to fuel melting, thus increasing the risk of actual melting during accident scenarios. It is therefore desirable to come up with a fuel design that lowers the fuel temperature while preserving the high linear power ratio and high coolant temperature. One possible solution is to separate the fertile (ThO{sub 2}) and fissile (PuO{sub 2}) fuel materials into different radial regions in each fuel pin. Previously-reported work found that by locating the fertile material at the centre and the fissile material at the periphery of the fuel pin, the fuel centreline temperature can be reduced by ∼650 K for fresh fuel compared to the case of a homogeneous (Th–Pu)O{sub 2} mixture for the same coolant temperature and linear power density. This work provides a justification for the observed reduction in fuel centreline temperature and suggests a systematic approach to lower the fuel temperature. It also extends the analysis to the dependence of the radial temperature profile on fuel burnup. The radial temperature profile is

Modeling and Simulation of the Direct Methanol Fuel Cell

Science.gov (United States)

Wohr, M.; Narayanan, S. R.; Halpert, G.

1996-01-01

From intro.: The direct methanol liquid feed fuel cell uses aqueous solutions of methanol as fuel and oxygen or air as the oxidant and uses an ionically conducting polymer membrane such as Nafion(sup r)117 and the electrolyte. This type of direct oxidation cell is fuel versatile and offers significant advantages in terms of simplicity of design and operation...The present study focuses on the results of a phenomenological model based on current understanding of the various processed operating in these cells.

Fight against fuel poverty. Levers, stakes and expectations of the fight against fuel poverty in housing

International Nuclear Information System (INIS)

Payen, Luc; Pamart, Isabelle; Lacroix, Olivier

2013-10-01

'Is in fuel poverty a person who feels in his particular housing difficulties have the necessary energy supply to the satisfaction of basic needs due to the inadequacy of resources or its habitat conditions'. The rising cost of energy commodities in the late 2000's, added to the poor thermal quality an important part of French homes, has led to the emergence of fuel poverty in the public debate. Legislative recognition of these situations with the law 'Grenelle II' (from which is extracted the definition above) marked a decisive step in the fight against this complex problem. Affecting nearly 5 million households in France, fuel poverty is a major challenge for societies wishing to successfully achieve their energy transition. In this new publication, ENEA reports on the main levers of the fight against fuel poverty, the obstacles encountered and the needs for new solutions

Processing of irradiated, enriched uranium fuels at the Savannah River Plant

Energy Technology Data Exchange (ETDEWEB)

Hyder, M L; Perkins, W C; Thompson, M C; Burney, G A; Russell, E R; Holcomb, H P; Landon, L F

1979-04-01

Uranium fuels containing /sup 235/U at enrichments from 1.1% to 94% are processed and recovered, along with neptunium and plutonium byproducts. The fuels to be processed are dissolved in nitric acid. Aluminum-clad fuels are disssolved using a mercury catalyst to give a solution rich in aluminum. Fuels clad in more resistant materials are dissolved in an electrolytic dissolver. The resulting solutions are subjected to head-end treatment, including clarification and adjustment of acid and uranium concentration before being fed to solvent extraction. Uranium, neptunium, and plutonium are separated from fission products and from one another by multistage countercurrent solvent extraction with dilute tri-n-butyl phosphate in kerosene. Nitric acid is used as the salting agent in addition to aluminum or other metal nitrates present in the feed solution. Nuclear safety is maintained through conservative process design and the use of monitoring devices as secondary controls. The enriched uranium is recovered as a dilute solution and shipped off-site for further processing. Neptunium is concentrated and sent to HB-Line for recovery from solution. The relatively small quantities of plutonium present are normally discarded in aqueous waste, unless the content of /sup 238/Pu is high enough to make its recovery desirable. Most of the /sup 238/Pu can be recovered by batch extraction of the waste solution, purified by counter-current solvent extraction, and converted to oxide in HB-Line. By modifying the flowsheet, /sup 239/Pu can be recovered from low-enriched uranium in the extraction cycle; neptunium is then not recovered. The solvent is subjected to an alkaline wash before reuse to remove degraded solvent and fission products. The aqueous waste is concentrated and partially deacidified by evaporation before being neutralized and sent to the waste tanks; nitric acid from the overheads is recovered for reuse.

Processing of irradiated, enriched uranium fuels at the Savannah River Plant

International Nuclear Information System (INIS)

Hyder, M.L.; Perkins, W.C.; Thompson, M.C.; Burney, G.A.; Russell, E.R.; Holcomb, H.P.; Landon, L.F.

1979-04-01

Uranium fuels containing 235 U at enrichments from 1.1% to 94% are processed and recovered, along with neptunium and plutonium byproducts. The fuels to be processed are dissolved in nitric acid. Aluminum-clad fuels are disssolved using a mercury catalyst to give a solution rich in aluminum. Fuels clad in more resistant materials are dissolved in an electrolytic dissolver. The resulting solutions are subjected to head-end treatment, including clarification and adjustment of acid and uranium concentration before being fed to solvent extraction. Uranium, neptunium, and plutonium are separated from fission products and from one another by multistage countercurrent solvent extraction with dilute tri-n-butyl phosphate in kerosene. Nitric acid is used as the salting agent in addition to aluminum or other metal nitrates present in the feed solution. Nuclear safety is maintained through conservative process design and the use of monitoring devices as secondary controls. The enriched uranium is recovered as a dilute solution and shipped off-site for further processing. Neptunium is concentrated and sent to HB-Line for recovery from solution. The relatively small quantities of plutonium present are normally discarded in aqueous waste, unless the content of 238 Pu is high enough to make its recovery desirable. Most of the 238 Pu can be recovered by batch extraction of the waste solution, purified by counter-current solvent extraction, and converted to oxide in HB-Line. By modifying the flowsheet, 239 Pu can be recovered from low-enriched uranium in the extraction cycle; neptunium is then not recovered. The solvent is subjected to an alkaline wash before reuse to remove degraded solvent and fission products. The aqueous waste is concentrated and partially deacidified by evaporation before being neutralized and sent to the waste tanks; nitric acid from the overheads is recovered for reuse

Innovative membrane development for fuel cells

CSIR Research Space (South Africa)

Vaivars, G

2011-10-01

Full Text Available The innovative membranes for alternative energy devices will be presented. An electrical car is long waited solution to environmental and fuel supply problems in transport. Most probably, the shift from a combustion engine to an electrical car...

Monitoring of releases from an irradiated fuel reprocessing plant

International Nuclear Information System (INIS)

Fitoussi, L.

1978-01-01

At its UP 2 plant, the La Hague facility reprocesses irradiated fuel by the PUREX process. The fuel stems from graphite/gas, natural-uranium reactors and pressurized or boiling water enriched-uranium reactors. The gaseous effluents are collected and purified by high-efficiency washing and filtration. After purification the gas stream is discharged into the atmosphere by a single stack, 100m high and 6m in diameter, located at a high point on the site (184m). The radionuclides released into the air are: krypton-85, iodine-129 and -131, and tritium. The liquid effluents are collected by drainage systems, which transfer them to the effluent treatment station in the case of active or suspect solutions. Active solutions undergo treatment by chemical and physical processes. After purification the waste water is released into the sea by an underwater drainage system 5km long, which brings the outlet point into the middle of a tidal current 2km offshore. The radionuclides contained in the purified waste water are fission products originating from irradiated fuels in only slightly variable proportions, in which ruthenium-rhodium-106 predominates. Traces of the transuranium elements are also found in these solutions

Proposed plan for critical experiments supporting thorium fuel cycle development

International Nuclear Information System (INIS)

Gore, B.F.

1978-09-01

A preliminary plan is proposed for critical experiments to provide data needed for the recycle of thorium based nuclear fuels. The sequence of experimentation starts with well moderated solutions followed by highly concentrated low moderated solutions. It then progresses through lattices moderated by water, by water plus soluble poisons, and by fissile solutions, to solutions poisoned by raschig rings and soluble poisons. Final experiments would treat lattices moderated by poisoned fissile solution, and arrays of stored fissile units

Modeling two-phase flow in PEM fuel cell channels

Energy Technology Data Exchange (ETDEWEB)

Wang, Yun; Basu, Suman; Wang, Chao-Yang [Electrochemical Engine Center (ECEC), and Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA 16802 (United States)

2008-05-01

This paper is concerned with the simultaneous flow of liquid water and gaseous reactants in mini-channels of a proton exchange membrane (PEM) fuel cell. Envisaging the mini-channels as structured and ordered porous media, we develop a continuum model of two-phase channel flow based on two-phase Darcy's law and the M{sup 2} formalism, which allow estimate of the parameters key to fuel cell operation such as overall pressure drop and liquid saturation profiles along the axial flow direction. Analytical solutions of liquid water saturation and species concentrations along the channel are derived to explore the dependences of these physical variables vital to cell performance on operating parameters such as flow stoichiometric ratio and relative humility. The two-phase channel model is further implemented for three-dimensional numerical simulations of two-phase, multi-component transport in a single fuel-cell channel. Three issues critical to optimizing channel design and mitigating channel flooding in PEM fuel cells are fully discussed: liquid water buildup towards the fuel cell outlet, saturation spike in the vicinity of flow cross-sectional heterogeneity, and two-phase pressure drop. Both the two-phase model and analytical solutions presented in this paper may be applicable to more general two-phase flow phenomena through mini- and micro-channels. (author)

Technical framework to facilitate foreign spent fuel storage and geologic disposal in Russia

International Nuclear Information System (INIS)

Jardine, L.J.; Halsey, W.G.; Cmith, C.F.

2000-01-01

The option of storage and eventual geologic disposal in Russia of spent fuel of US origin used in Taiwan provides a unique opportunity that can benefit many parties. Taiwan has a near term need for a spent fuel storage and geologic disposal solution, available financial resources, but limited prospect for a timely domestic solution. Russia has significant spent fuel storage and transportation management experience, candidate storage and repository sites, but limited financial resources available for their development. The US has interest in Taiwan energy security, national security and nonproliferation interests in Russian spent fuel storage and disposal and interest in the US origin fuel. While it is understood that such a project includes complex policy and international political issues as well as technical issues, the goal of this paper is to begin the discussion by presenting a technical path forward to establish the feasibility of this concept for Russia

The economy of the nuclear fuel cycle

Energy Technology Data Exchange (ETDEWEB)

Stoll, W [Alpha Chemie und Metallurgie G.m.b.H. (ALKEM), Hanau (Germany, F.R.)

1989-07-01

Heat extracted from nuclear fuel costs by a factor of 3 to 7 less than heat from conventional fossile fuel. So, nuclear fuel per se has an economical advantage, decreased however partly by higher nuclear plant investment costs. The standard LWR design does not allow all the fission energy stored in the fuel during on cycle to be used. It is therefore the most natural approach to separate fissionable species from fission products and consume them by fissioning. Whether this is economically justified as opposed by storing them indefinitely with spent fuel has widely been debated. The paper outlines the different approaches taken by nuclear communities worldwide and their perceived or proven rational arguments. It will balance economic and other factors for the near and distant future including advanced reactor concepts. The specific solution within the German nuclear programme will be explained, including foreseeable future trends. (orig.).

Dual-fuel natural gas/diesel engines: Technology, performance, and emissions

Science.gov (United States)

Turner, S. H.; Weaver, C. S.

1994-11-01

An investigation of current dual-fuel natural gas/diesel engine design, performance, and emissions was conducted. The most pressing technological problems associated with dual-fuel engine use were identified along with potential solutions. It was concluded that dual-fuel engines can achieve low NO(sub x) and particulate emissions while retaining fuel-efficiency and BMEP levels comparable to those of diesel engines. The investigation also examined the potential economic impact of dual-fuel engines in diesel-electric locomotives, marine vessels, farm equipment, construction, mining, and industrial equipment, and stand-alone electricity generation systems. Recommendations for further additional funding to support research, development, and demonstration in these applications were then presented.

LMFBR fuel cycle studies progress report, August 1972, No. 42

International Nuclear Information System (INIS)

Unger, W.E.; Blanco, R.E.; Crouse, D.J.; Irvine, A.R.; Watson, C.D.

1972-10-01

This report continues a series outlining progress in the development of methods for reprocessing of LMFBR fuels. Development work is reported on problems of irradiated fuel transport to the processing facility, the dissolution of the fuel and the chemical recovery of PuO 2 --UO 2 values, the containment of volatile fission products, product purification, conversion of fuel processing plant product nitrate solutions to solids suitable for shipping and for subsequent fuel fabrication. Pertinent experimental results are presented for the information of those immediately concerned with the field. Detailed description of experimental work and data are included in the topical reports and in the Chemical Technology Division Annual Reports

Reprocessing ability of high density fuels for research and test reactors

International Nuclear Information System (INIS)

Gay, A.; Belieres, M.

1997-01-01

The development of a new high density fuel is becoming a key issue for Research Reactors operators. Such a new fuel should be a Low Enrichment Uranium (LEU) fuel with a high density, to improve present in core performances. It must be compatible with the reprocessing in an industrial plant to provide a steady back-end solution. Within the framework of a work group CEA/CERCA/COGEMA on new fuel development for Research Reactors, COGEMA has performed an evaluation of the reprocessing ability of some fuel dispersants selected as good candidates. The results will allow US to classify these fuel dispersants from a reprocessing ability point of view. (author)

Effect of fuels on conductivity, dielectric and humidity sensing properties of ZrO2 nanocrystals prepared by low temperature solution combustion method

Directory of Open Access Journals (Sweden)

H.C. Madhusudhana

2016-09-01

Full Text Available ZrO2 nanopowders were synthesized by low temperature solution combustion method using two different fuels namely glycine and oxalyldihydrazide (ODH. The phase confirmation was done by powder X-ray diffraction (PXRD and Raman spectral analysis. Use of glycine resulted in ZrO2 with mixture of tetragonal and monoclinic phase with average crystallite size of ∼30 nm. However, ODH as fuel aids in the formation of ZrO2 with mixture of tetragonal and cubic phase with average crystallite size ∼20 nm. Further, in present work we present novel way to tune conductivity property of the nano ZrO2. We show that merely changing the fuel from glycine to ODH, we obtain better DC conductivity and dielectric constant. On the other hand use of glycine leads to the formation of ZrO2 with better AC conductivity and humidity sensing behavior. The dielectric constants calculated for samples prepared with glycine and ODH were found to be 45 and 26 respectively at 10 MHz. The AC and DC conductivity values of the samples prepared with glycine was found to be 9.5 × 10−4 S cm−1, 1.1 × 10−3 S cm−1 and that of ODH was 7.6 × 10−4 S cm−1, 3.6 × 10−3 S cm−1 respectively.

Panorama 2009 - aviation and alternative fuels

International Nuclear Information System (INIS)

2008-01-01

Several key priorities have been targeted for development in the aviation industry: diversifying energy resources, keeping consumption levels under control and reducing polluting emissions to improve air quality. Like the road transport sector, the air transport sector is mounting a determined effort to reduce the level of its greenhouse gas emissions. Among the various solutions under consideration, alternative fuels are attracting particular attention. However, not all alternative solutions can be exploited, because of the constraints specific to the use of aircraft. A precise assessment should be made of all possible solutions to determine which ones should take preference

Regulatory experience with fuel failures in Switzerland

International Nuclear Information System (INIS)

Adam, L.

2015-01-01

In this paper the main ENSI activities like: supervision of reactor and radiation safety and security; supervision of safety of transports of nuclear materials and assess the safety of proposed solutions for the geological disposal are listed. Recent events concerning the reactor core, common causes for fuel failures, findings during inspections and potential root cause for fuel failures are discussed. Management of fuel failures, started from reporting of the event – evaluation of the need of imminent action; identification of the fuel element if possible till evaluation by the plant and fuel vendor and allowance by ENSI for repair of the fuel element and definition of measures (short and long term) are also presented. The following Conclusions by ENSI about status of fuel failures are made: 1) Number of fuel failures was reduced regardless more economic operation in all plants; 2) Old PWR and BWR reactors achieved 15 to 29 years operation without leakers, but two minor fuel damage during fuel handling appeared; 3) Newer plants are not better in achieving operation without leakers than older plants; 4) Technical improvements at fuel elements parallel to changes in operation strategy and improvements in manufacturing quality but single effects difficult to judge. The issues about how to implement “Zero Failure Rates” in regulations and how to achieve “Zero Failure Rates” as well as some future measures by ENSI are discussed

Fuel Continuous Mixer ? an Approach Solution to Use Straight Vegetable Oil for Marine Diesel Engines

OpenAIRE

Đặng Van Uy; Tran The Nam

2018-01-01

The vegetable oil is well known as green fuel for diesel engines due to its low sunphur content and renewable stock. However, there are some problems raising when vegetable oil is used as fuel for diesel engines such as highly effected by cold weather, lower general efficiency, separation in layer if mixed with diesel oil and so on. To overcome that disadvantiges, the authors propose a new idea that to use a continuous fuel mixer to blend vegetable oil with diesel oil to make so called a mixe...

Dissolution Flowsheet for High Flux Isotope Reactor Fuel

Energy Technology Data Exchange (ETDEWEB)

Daniel, W. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Rudisill, T. S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); O' Rourke, P. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Karay, N. S [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-09-27

As part of the Spent Nuclear Fuel (SNF) processing campaign, H-Canyon is planning to begin dissolving High Flux Isotope Reactor (HFIR) fuel in late FY17 or early FY18. Each HFIR fuel core contains inner and outer fuel elements which were fabricated from uranium oxide (U₃O₈) dispersed in a continuous Al phase using traditional powder metallurgy techniques. Fuels fabricated in this manner, like other SNF’s processed in H-Canyon, dissolve by the same general mechanisms with similar gas generation rates and the production of H₂. The HFIR fuel cores will be dissolved and the recovered U will be down-blended into low-enriched U. HFIR fuel was previously processed in H-Canyon using a unique insert in both the 6.1D and 6.4D dissolvers. Multiple cores will be charged to the same dissolver solution maximizing the concentration of dissolved Al. The objective of this study was to identify flowsheet conditions through literature review and laboratory experimentation to safely and efficiently dissolve the HFIR fuel in H-Canyon. Laboratory-scale experiments were performed to evaluate the dissolution of HFIR fuel using both Al 1100 and Al 6061 T6 alloy coupons. The Al 1100 alloy was considered a representative surrogate which provided an upper bound on the generation of flammable (i.e., H₂) gas during the dissolution process. The dissolution of the Al 6061 T6 alloy proceeded at a slower rate than the Al 1100 alloy, and was used to verify that the target Al concentration in solution could be achieved for the selected Hg concentration. Mass spectrometry and Raman spectroscopy were used to provide continuous monitoring of the concentration of H₂ and other permanent gases in the dissolution offgas, allowing the development of H₂ generation rate profiles. The H₂ generation rates were subsequently used to evaluate if a full HFIR core could be dissolved in an H-Canyon dissolver without exceeding 60% of the

Cross-linked PEEK-WC proton exchange membrane for fuel cell

CSIR Research Space (South Africa)

Lou, H

2009-10-01

Full Text Available was added to the 15 wt% of SsPEEK-WC solution in NMP with magnetic stir. The solution was cast on a glass Petri dish. The solvent was then removed in a vacuum oven at 130 °C. The membrane was peeled off from the Petri dish. Thereafter, the membrane... and polyetherketone for fuel cell applications. Journal of Membrane Science, 2001. 185(1): p. 41-58. [6] Kerres, J.A., Development of ionomer membranes for fuel cells. Journal of Membrane Science, 2001. 185(1): p. 3-27. [7] Basile, A.; Paturzo, L.; Iulianelli, A...

Mechanistic studies of the oxidation of soluble species of ruthenium in nitric acid solutions. Application to the removal of ruthenium from nuclear fuel dissolution solutions

International Nuclear Information System (INIS)

Carron, V.

2001-01-01

Ruthenium is one of the most troublesome fission products during nuclear fuel reprocessing. His removal from nitric acid fuel dissolution solutions, above the PUREX process, is under consideration. Electro-volatilization could be a possible way to eliminate this element. It consists in the oxidation of soluble ruthenium species coupled with the volatilization of formed RuO 4 . Soluble species are nitrate and nitro complexes of nitrosyl ruthenium RuNO 3+ . The first part of this work deals with the direct oxidation of RuNO 3+ at a golden or a platinum anode. It has been investigated by cyclic voltammetry and infrared and UV-visible reflectance spectroscopy. The oxidation of RuNO 3+ begins with an adsorption step, which precedes the formation of RuO 4 . Then a reaction between RuO 4 and RuNO 3+ occurs to produce a Ru IV compound, which is also electro-oxidized to RuO 4 . The second part concerns potentiostatic electro-volatilization experiences. The rate of electro-volatilization decreases with increasing HNO 3 concentration. At low concentrations, kinetic is controlled by the volatilization of RuO 4 . The rate-determining step is the oxidation of RuNO 3+ at concentrations higher than 1 M. In HNO 3 4 M, the addition of AgNO 3 is required to accelerate the oxidation of RuNO 3+ . The last part is devoted to the study of the indirect oxidation of RuNO 3+ . The electrocatalytic power of electro-generated Ag II is illustrated by voltammetric techniques and potentiostatic electrolysis. The existence of a limit concentration of AgNO 3 is shown (which value depends on experimental conditions) beyond which kinetic is controlled by the RuO 4 volatilization step. These results indicate that the electro-volatilization kinetic could be increased by optimizing the volatilization conditions. (author)

Advanced fuel cycles in CANDU reactors

International Nuclear Information System (INIS)

Green, R.E.; Boczar, P.G.

1990-04-01

This paper re-examines the rationale for advanced nuclear fuel cycles in general, and for CANDU advanced fuel cycles in particular. The traditional resource-related arguments for more uranium nuclear fuel cycles are currently clouded by record-low prices for uranium. However, the total known conventional uranium resources can support projected uranium requirements for only another 50 years or so, less if a major revival of the nuclear option occurs as part of the solution to the world's environmental problems. While the extent of the uranium resource in the earth's crust and oceans is very large, uncertainty in the availability and price of uranium is the prime resource-related motivation for advanced fuel cycles. There are other important reasons for pursuing advanced fuel cycles. The three R's of the environmental movement, reduce, recycle, reuse, can be achieved in nuclear energy production through the employment of advanced fuel cycles. The adoption of more uranium-conserving fuel cycles would reduce the amount of uranium which needs to be mined, and the environmental impact of that mining. Environmental concerns over the back end of the fuel cycle can be mitigated as well. Higher fuel burnup reduces the volume of spent fuels which needs to be disposed of. The transmutation of actinides and long-lived fission products into short-lived fission products would reduce the radiological hazard of the waste from thousands to hundreds of years. Recycling of uranium and/or plutonium in spent fuel reuses valuable fissile material, leaving only true waste to be disposed of. Advanced fuel cycles have an economical benefit as well, enabling a ceiling to be put on fuel cycle costs, which are

Nuclear fuel particle and method of production

International Nuclear Information System (INIS)

Wagner-Loffler, M.

1975-01-01

The core consisting of fuel oxide (UO 2 or Th or Pu oxide) of a fuel particle coated with carbon-contained material is enriched with a small addition (max 6 wt.%) of a Ba or Sr compound (atomic ratio for nuclear fuel oxide Ba being 5 - 10 : 1) which is to prevent fission products breaking the protective carbon and/or silicon carbide coating; the Ba or Sr molybdate generated is to reduce the pressure of the carbon dioxide produced. Methods to manufacture such nuclear fuel particles are proposed where 1) an agglomerisation and shaping of the spheres in a fast cycling bowle and 2) a formation of drops from a colloidal solution which are made to congeal in a liquid paraffin column, take place followed by the pyrolytic coating of the particles. (UWI/LH) [de

Hydrogen as alternative clean fuel: Economic analysis

International Nuclear Information System (INIS)

Coiante, D.

1995-03-01

In analogy to biofuel production from biomasses, the electrolytic conversion of other renewable energies into hydrogen as an alternative clean fuel is considered. This solution allows the intermittent renewable energy sources, as photovoltaics and wind energy, to enhance their development and enlarge the role into conventional fuel market. A rough economic analysis of hydrogen production line shows the costs, added by electrolysis and storage stages, can be recovered by properly accounting for social and environmental costs due to whole cycle of conventional fuels, from production to use. So, in a perspective of attaining the economic competitiveness of renewable energy, the hydrogen, arising from intermittent renewable energy sources, will be able to compete in the energy market with conventional fuels, making sure that their substitution will occur in a significant amount and the corresponding environment

Reuse of discharged fuel in Bohunice-1,2 units

International Nuclear Information System (INIS)

Chrapciak, V.; Majercik, J.; Kacmar, M.

2003-01-01

During the reconstruction of Bohunice-1,2 units (1997 - 2001), their cycle lengths dropped to very short values. Because of 4-year limit to fuel residence time, refuelling with fresh 2.4 % enriched assemblies seemed to be a solution of the problem. The paper describes the implementation of a final decision to reuse 3.6 % enriched fuel discharged after 3-year irradiation in previous cycles. This decision led to a large-scale moving of discharged assemblies from spent fuel pools back to reactors (Authors)

Alternative fuels for the French fast breeder reactors programme

International Nuclear Information System (INIS)

Bailly, H.; Bernard, H.; Mansard, B.

1989-01-01

French fast breeder reactors use mixed oxide as reference fuel. A great deal of experience has been gained in the behaviour and manufacture of oxide fuel, which has proved to be the most suitable fuel for future commercial breeder reactors. However, France is maintaining long-term alternative fuels programme, in order to be in a position to satisfy eventually new future reactor design and operational requirements. Initially, the CEA in France developed a carbide-based, sodium-bonded fuel designed for a high specific power. The new objective of the alternative fuels programme is to define a fuel which could replace the oxide without requiring any significant changes to the operating conditions, fuel cycle processes or facilities. The current program concentrates on a nitride-based, helium-bonded fuel, bearing in mind the carbide solution. The paper describes the main characteristics required, the manufacturing process as developed, the inspection methods, and the results obtained. Present indications are that the industrial manufacture of mixed nitride is feasible and that production costs for nitride and oxide fuels would be not significantly different. (author) 8 refs., 2 figs

Numerical Studies on Controlling Gaseous Fuel Combustion by Managing the Combustion Process of Diesel Pilot Dose in a Dual-Fuel Engine

Directory of Open Access Journals (Sweden)

Mikulski Maciej

2015-06-01

Full Text Available Protection of the environment and counteracting global warming require finding alternative sources of energy. One of the methods of generating energy from environmentally friendly sources is increasing the share of gaseous fuels in the total energy balance. The use of these fuels in compression-ignition (CI engines is difficult due to their relatively high autoignition temperature. One solution for using these fuels in CI engines is operating in a dualfuel mode, where the air and gas mixture is ignited with a liquid fuel dose. In this method, a series of relatively complex chemical processes occur in the engine's combustion chamber, related to the combustion of individual fuel fractions that interact with one another. Analysis of combustion of specific fuels in this type of fuel injection to the engine is difficult due to the fact that combustion of both fuel fractions takes place simultaneously. Simulation experiments can be used to analyse the impact of diesel fuel combustion on gaseous fuel combustion. In this paper, we discuss the results of simulation tests of combustion, based on the proprietary multiphase model of a dual-fuel engine. The results obtained from the simulation allow for analysis of the combustion process of individual fuels separately, which expands the knowledge obtained from experimental tests on the engine.

Solar energised transport solution and customer preferences and opinions about alternative fuel Vehicles – the case of slovenia

Directory of Open Access Journals (Sweden)

Matjaž KNEZ

2015-09-01

Full Text Available Authorities in Slovenia and other EU member states are confronted with problems of city transportation. Fossil-fuel based transport poses two chief problems – local and global pollution, and dwindling supplies and ever increasing costs. An elegant solution is to gradually replace the present automobile fleet with low emission vehicles. This article first explores the economics and practical viability of the provision of solar electricity for the charging of electric vehicles by installation of economical available PV modules and secondly the customer preferences and opinions about alternative low emission vehicles. Present estimates indicate that for the prevailing solar climate of Celje – a medium-sized Slovenian town – the cost would be only 2.11€ cents/kWh of generated solar electricity. Other results have also revealed that the most relevant factor for purchasing low emission vehicle is total vehicle price.

Investigation of the effects of radiolytic-gas bubbles on the long-term operation of solution reactors for medical-isotope production

Science.gov (United States)

Souto Mantecon, Francisco Javier

One of the most common and important medical radioisotopes is 99Mo, which is currently produced using the target irradiation technology in heterogeneous nuclear reactors. The medical isotope 99Mo can also be produced from uranium fission using aqueous homogeneous solution reactors. In solution reactors, 99Mo is generated directly in the fuel solution, resulting in potential advantages when compared with the target irradiation process in heterogeneous reactors, such as lower reactor power, less waste heat, and reduction by a factor of about 100 in the generation of spent fuel. The commercial production of medical isotopes in solution reactors requires steady-state operation at about 200 kW. At this power regime, the formation of radiolytic-gas bubbles creates a void volume in the fuel solution that introduces a negative coefficient of reactivity, resulting in power reduction and instabilities that may impede reactor operation for medical-isotope production. A model has been developed considering that reactivity effects are due to the increase in the fuel-solution temperature and the formation of radiolytic-gas bubbles. The model has been validated against experimental results from the Los Alamos National Laboratory uranyl fluoride Solution High-Energy Burst Assembly (SHEBA), and the SILENE uranyl nitrate solution reactor, commissioned at the Commissariat a l'Energie Atomique, in Valduc, France. The model shows the feasibility of solution reactors for the commercial production of medical isotopes and reveals some of the important parameters to consider in their design, including the fuel-solution type, 235U enrichment, uranium concentration, reactor vessel geometry, and neutron reflectors surrounding the reactor vessel. The work presented herein indicates that steady-state operation at 200 kW can be achieved with a solution reactor consisting of 120 L of uranyl nitrate solution enriched up to 20% with 235U and a uranium concentration of 145 kg/m3 in a graphite

Consequences of the increase of burnup on the fuel

International Nuclear Information System (INIS)

Melin, P.; Lavoine, O.; Houdaille, B.

1986-04-01

The examinations carried out on the FRAGEMA fuel of EDF reactors show its good behavior in service. The results of research and development programs developed by EDF, FGA and the CEA show that this fuel can be irradiated up to a high burnup, and allow to point out the axies of research to improve still the performance of the product in a more and more soliciting environment (increase of power and burnup coupled with load following). Among the solutions considered, there are the design and fabrication adjustments (geometry, initial pressurization), more fundamental changes concerning fuel cans and fuel pellets, which need still research and development programs [fr

Augmented lagrange hopfield network for economic dispatch with multiple fuel options

International Nuclear Information System (INIS)

Dieu, Vo Ngoc; Ongsakul, Weerakorn; Polprasert, Jirawadee

2011-01-01

This paper proposes an augmented Lagrange Hopfield network (ALHN) for solving economic dispatch (ED) problem with multiple fuel options. The proposed ALHN method is a continuous Hopfield neural network with its energy function based on augmented Lagrangian function. The advantages of ALHN over the conventional Hopfield neural network are easier use, more general applications, faster convergence, better optimal solution, and larger scale of problem implementation. The method solves the problem by directly searching the most suitable fuel among the available fuels of each unit and finding the optimal solution for the problem based on minimization of the energy function of the continuous Hopfield neural network. The proposed method is tested on systems up to 100 units and the obtained results are compared to those from other methods in the literature. The results have shown that the proposed method is efficient for solving the ED problem with multiple fuel options and favorable for implementation in large scale problems.

Alternative Sources of Energy - An Introduction to Fuel Cells

Science.gov (United States)

Merewether, E.A.

2003-01-01

Fuel cells are important future sources of electrical power and could contribute to a reduction in the amount of petroleum imported by the United States. They are electrochemical devices similar to a battery and consist of a container, an anode, a cathode, catalysts, an intervening electrolyte, and an attached electrical circuit. In most fuel cell systems, hydrogen is supplied to the anode and oxygen to the cathode which results in the production of electricity, water, and heat. Fuel cells are comparatively efficient and reliable, have no moving parts, operate without combustion, and are modular and scale-able. Their size and shape are flexible and adaptable. In operation, they are nearly silent, are relatively safe, and generally do not pollute the environment. During recent years, scientists and engineers have developed and refined technologies relevant to a variety of fuel cells. Types of fuel cells are commonly identified by the composition of their electrolyte, which could be either phosphoric acid, an alkaline solution, a molten carbonate, a solid metal oxide, or a solid polymer membrane. The electrolyte in stationary power plants could be phosphoric acid, molten carbonates, or solid metal oxides. For vehicles and smaller devices, the electrolyte could be an alkaline solution or a solid polymer membrane. For most fuel cell systems, the fuel is hydrogen, which can be extracted by several procedures from many hydrogen-bearing substances, including alcohols, natural gas (mainly methane), gasoline, and water. There are important and perhaps unresolved technical problems associated with using fuel cells to power vehicles. The catalysts required in several systems are expensive metals of the platinum group. Moreover, fuel cells can freeze and not work in cold weather and can be damaged by impacts. Storage tanks for the fuels, particularly hydrogen, must be safe, inexpensive, of a reasonable size, and contain a supply sufficient for a trip of several hundred miles

CFTSIM-ITER dynamic fuel cycle model

International Nuclear Information System (INIS)

Busigin, A.; Gierszewski, P.

1998-01-01

Dynamic system models have been developed for specific tritium systems with considerable detail and for integrated fuel cycles with lesser detail (e.g. D. Holland, B. Merrill, Analysis of tritium migration and deposition in fusion reactor systems, Proceedings of the Ninth Symposium Eng. Problems of Fusion Research (1981); M.A. Abdou, E. Vold, C. Gung, M. Youssef, K. Shin, DT fuel self-sufficiency in fusion reactors, Fusion Technol. (1986); G. Spannagel, P. Gierszewski, Dynamic tritium inventory of a NET/ITER fuel cycle with lithium salt solution blanket, Fusion Eng. Des. (1991); W. Kuan, M.A. Abdou, R.S. Willms, Dynamic simulation of a proposed ITER tritium processing system, Fusion Technol. (1995)). In order to provide a tool to understand and optimize the behavior of the ITER fuel cycle, a dynamic fuel cycle model called CFTSIM is under development. The CFTSIM code incorporates more detailed ITER models, specifically for the important isotope separation system, and also has an easier-to-use graphical interface. This paper provides an overview of CFTSIM Version 1.0. The models included are those with significant and varying tritium inventories over a test campaign: fueling, plasma and first wall, pumping, fuel cleanup, isotope separation and storage. An illustration of the results is shown. (orig.)

What are the priorities in the fight against fuel poverty? For sustainable solutions, consistent with our commitments. Report no. 18

International Nuclear Information System (INIS)

Joly, Guillaume; Guibert, Geraud

2016-03-01

In our country, over 5 million households find it hard to pay their energy bills. Heating, lighting and transport are nevertheless essential needs, and one cannot lead a normal life if these needs are not met. Among these households, a certain number find themselves in a genuine situation of fuel poverty. They often rent their homes from the private sector and do not have the means to cover their expenses. These situations present social, but also environmental challenges. In the fight against climate change, the priority must be to eliminate the waste resulting from situations of energy 'leakage'. If sustainable solutions are not found, rising energy prices, which are necessary to reduce greenhouse gas emissions and our carbon footprint, will be unbearably high for a growing number of households and will therefore not be implemented. The fight against fuel poverty has improved in recent years, and new measures formulated by the Energy Transition Law of 2015 are being implemented: energy cheques, energy-saving 'poverty' certificates, etc. But these initiatives are not widely used, they are not well coordinated, and most often they are only calculated on the basis of income. Yet the situation of a household with a low income but living in well-isolated social housing is very different from that of a household living in a home with high energy loss. It is now essential to introduce more clarity and coherence into this system, prioritising long-term solutions which are the only ones capable of reconciling social and environmental priorities. Urgent work needs to be done to tackle energy leakage, particularly in private-sector rental properties, and, as far as possible, we must avoid providing direct aid for fossil fuel use, since this is contrary to the aims of the Paris Climate Change Agreement. Following on from a rigorous and exhaustive assessment, this brief proposes, within the framework of current reforms as well as beyond, to: 1) Fully

Experimental investigation of the performance and emissions of diesel engines by a novel emulsified diesel fuel

International Nuclear Information System (INIS)

Chen, Zhenbin; Wang, Xiaochen; Pei, Yiqiang; Zhang, Chengliang; Xiao, Mingwei; He, Jinge

2015-01-01

Highlights: • A novel bio-fuel, glucose solution emulsified diesel fuel, is evaluated. • Emulsified diesel has comparable brake thermal efficiency. • NO X emissions decrease with emulsified fuel at all loads. • Soot emissions decrease with emulsified fuel except at a few operating points. - Abstract: The subject of this paper was to study the performance and emissions of two typical diesel engines using glucose solution emulsified diesel fuel. Emulsified diesel with a 15% glucose solution by mass fraction was used in diesel engines and compared with pure diesel. For the agricultural diesel engine, performance and emission characteristics were measured under various engine loads. The results showed that the brake thermal efficiencies were improved using emulsified diesel fuel. Emulsified fuel decreased NO x and soot emissions except at a few specific operating conditions. HydroCarbon (HC) and CO emissions were increased. For the automotive diesel engine, performance and emissions were measured using the 13-mode European Stationary Cycle (ESC). It was found that brake thermal efficiencies of emulsified diesel and pure diesel were comparable at 75% and 100% load. Soot emissions decreased significantly while NO x emissions decreased slightly. HC emissions increased while CO emissions decreased at some operating conditions

Analytical solution and experimental validation of the energy management problem for fuel cell hybrid vehicles

NARCIS (Netherlands)

P.P.J. van den Bosch; Edwin Tazelaar; M. Grimminck; Stijn Hoppenbrouwers; Bram Veenhuizen

2011-01-01

The objective of an energy management strategy for fuel cell hybrid propulsion systems is to minimize the fuel needed to provide the required power demand. This minimization is defined as an optimization problem. Methods such as dynamic programming numerically solve this optimization problem.

EXPERIMENTAL SENSOR OF THE BENZOETHANOL COMPOSITION FOR ENGINE FUEL SYSTEM

Directory of Open Access Journals (Sweden)

V. Bgantsev

2017-12-01

Full Text Available An important aspect of the economy of internal combustion engine on benzoethanol is the accuracy of regulation of the fuel-air mixture composition. This task is complicated by fluctuations in the composition of benzoethanol, depending on the refueling of the vehicle at various filling stations. In this connection, there is a need to control the composition of benzoethanol in the fuel system of the engine and adjust the fuel supply system. With this purpose, fuel systems are equipped with special sensors that generate a signal, depending on the alcohol content of the mixed fuel. In the article one of the design solutions of the experimental sensor of the benzoethanol composition and the results of its testing with fuels of various composition are given.

Radiographic inspection and densitometric evaluation of CP-5 reactor fuel

International Nuclear Information System (INIS)

Staroba, J.F.; Knoerzer, T.W.

1978-02-01

This report covers the radiographic and densitometric techniques used as part of a quality verification program for CP-5 reactor fuel by the Nondestructive Assay Section of the Special Materials Division. Other nondestructive tests used were ultrasonic and gamma-ray spectrometry. The main objectives were to perform a one-hundred percent radiographic inspection of the fuel tubes and to derive a quantitative relationship between fuel thickness and film density with the use of fabricated fuel step wedges. By the use of tangential x-ray techniques, measurements were made of fuel peaks or ''hot spots'' that protruded above the main fuel line. Other general problems in radiographic inspection and solutions for the upgrading of the total radiographic inspection program are also discussed

Radiometric determination of 90Sr in the dissolver solution of the spent PHWR fuel after its separation with solvent extraction and extraction chromatography

International Nuclear Information System (INIS)

Kulkarni, P.G.; Gupta, K.K.; Pant, D.K.; Bhalerao, B.A.; Gurba, P.B.; Janardan, P.; Changrani, R.D.; Dey, P.K.; Pathak, P.N.; Mohapatra, P.K.; Manchanda, V.K.

2010-01-01

A simple radiometric method for 90 Sr determination in the dissolver solution of the PHWR spent fuel has been developed.The method involves the quantitative separation of Sr from the associated actinides and other fission products by solvent extraction with 30% trialkylphosphine oxide (TRPO) -n-dodecane followed by extraction chromatography with XAD-7-Di-butylcyclohexano-18-crown-6 resin. The separation scheme yields quantitative recovery of 90 Sr and the separated 90 Sr was found to be radiochemically pure. 90 Sr was estimated by β-radiometry and the precision of the method at 5 mCi/mL level was 2% (RSD). (author)

Selection of Technical Solutions for the Management of Radioactive Waste

International Nuclear Information System (INIS)

2017-07-01

The objectives of this publication are to identify and critically review the criteria to be considered while selecting waste management technologies; summarize, evaluate, rank and compare the different technical solutions; and offer a systematic approach for selecting the best matching solution. This publication covers the management of radioactive waste from all nuclear operations, including waste generated from research reactors, power reactors, and nuclear fuel cycle activities including high level waste (HLW) arising from reprocessing and spent nuclear fuel declared as waste (SFW), as well as low level waste (LLW) and intermediate level waste (ILW) arising from the production and use of radionuclides in industry, agriculture, medicine, education and research.

Army Demonstration of Light Obscuration Particle Counters for Monitoring Aviation Fuel Contamination

Science.gov (United States)

2013-05-07

Hydraulic industry has utilized this technology for decades and created a mature process •Hydraulic industry has developed recognized calibration ...Vehicle Fuel Tank Fuel Injector Aviation Fuel DEF (AUST) 5695B 18/16/13 Parker 18/16/13 14/10/7 Pamas/Parker/Particle Solutions 19/17/12 U.S. Army 19...17/14/13* Diesel Fuel World Wide Fuel Charter 4th 18/16/13 DEF (AUST) 5695B 18/16/13 Bosch/Cummins 18/16/13 Donaldson 22/21/18 14/13/11 12/9/6 P ll

Hydrogen and fuel cells emerging technologies and applications

CERN Document Server

Sorensen (Sorensen), Bent

2011-01-01

A hydrogen economy, in which this one gas provides the source of all energy needs, is often touted as the long-term solution to the environmental and security problems associated with fossil fuels. However, before hydrogen can be used as fuel on a global scale we must establish cost effective means of producing, storing, and distributing the gas, develop cost efficient technologies for converting hydrogen to electricity (e.g. fuel cells), and creating the infrastructure to support all this. Sorensen is the only text available that provides up to date coverage of all these issues at a level

The French UMo group contribution to new LEU fuel development

International Nuclear Information System (INIS)

Hamy, J.M.; Lemoine, P.; Huet, F.; Jarousse, C.; Emin, J.L.

2005-01-01

The French UMo Group was based on a close collaboration between CEA and AREVA's companies strongly involved in the MTR field. The aim of this program was to deliver industrially a high performance LEU UMo fuel able to be reprocessed, and suitable for a wide range of Research Reactor, covering the expected needs for MTR next generation. Since 1999, the program has been focused on industrial aspects with the intention to deal with the whole fuel cycle: manufacturing, irradiation behaviour, fuel characterisation, code development and reprocessing validation. It has been based on the fabrication of full-sized U-7%Mo fuel plates with a density up to 8 gU/cm 3 . The dedicated and advanced R and D means provided by the CEA have been used intensively with the contribution of HFR and BR2 facilities in Europe. This paper presents a synthesis of the program and the corresponding significant results obtained. These results have played a major role as regards the UMo dispersion fuel qualification route by issuing, for the first time, evidence of severe performance limitations. Consequently, the global international effort to develop and qualify a high density LEU UMo fuel has been definitively re-routed and forced to overcome these discrepancies by exploring new technical solutions. A French extended program sustained by a CEA and CERCA collaboration has been launched in 2004 in order to develop a suitable UMo fuel solution. UMo dispersion and monolithic fuel are both investigated through three new full-sized plate irradiations planned in OSIRIS. (author)

Development of PRIME for irradiation performance analysis of U-Mo/Al dispersion fuel

Science.gov (United States)

Jeong, Gwan Yoon; Kim, Yeon Soo; Jeong, Yong Jin; Park, Jong Man; Sohn, Dong-Seong

2018-04-01

A prediction code for the thermo-mechanical performance of research reactor fuel (PRIME) has been developed with the implementation of developed models to analyze the irradiation behavior of U-Mo dispersion fuel. The code is capable of predicting the two-dimensional thermal and mechanical performance of U-Mo dispersion fuel during irradiation. A finite element method was employed to solve the governing equations for thermal and mechanical equilibria. Temperature- and burnup-dependent material properties of the fuel meat constituents and cladding were used. The numerical solution schemes in PRIME were verified by benchmarking solutions obtained using a commercial finite element analysis program (ABAQUS). The code was validated using irradiation data from RERTR, HAMP-1, and E-FUTURE tests. The measured irradiation data used in the validation were IL thickness, volume fractions of fuel meat constituents for the thermal analysis, and profiles of the plate thickness changes and fuel meat swelling for the mechanical analysis. The prediction results were in good agreement with the measurement data for both thermal and mechanical analyses, confirming the validity of the code.

Molybdenum solubility in aluminium nitrate solutions

Energy Technology Data Exchange (ETDEWEB)

Heres, X.; Sans, D.; Bertrand, M.; Eysseric, C. [CEA, Centre de Marcoule, Nuclear Energy Division, DRCP, BP 17171, 30207 Bagnols-sur-Ceze Cedex (France); Brackx, E.; Domenger, R.; Excoffier, E. [CEA, Centre de Marcoule, Nuclear Energy Division, DTEC, BP 17171, 30207 Bagnols-sur-Ceze Cedex (France); Valery, J.F. [AREVA-NC, DOR/RDP, Paris - La Defense (France)

2016-07-01

For over 60 years, research reactors (RR or RTR for research testing reactors) have been used as neutron sources for research, radioisotope production ({sup 99}Mo/{sup 99m}Tc), nuclear medicine, materials characterization, etc... Currently, over 240 of these reactors are in operation in 56 countries. They are simpler than power reactors and operate at lower temperature (cooled to below 100 C. degrees). The fuel assemblies are typically plates or cylinders of uranium alloy and aluminium (U-Al) coated with pure aluminium. These fuels can be processed in AREVA La Hague plant after batch dissolution in concentrated nitric acid and mixing with UOX fuel streams. The aim of this study is to accurately measure the solubility of molybdenum in nitric acid solution containing high concentrations of aluminium. The higher the molybdenum solubility is, the more flexible reprocessing operations are, especially when the spent fuels contain high amounts of molybdenum. To be most representative of the dissolution process, uranium-molybdenum alloy and molybdenum metal powder were dissolved in solutions of aluminium nitrate at the nominal dissolution temperature. The experiments showed complete dissolution of metallic elements after 30 minutes long stirring, even if molybdenum metal was added in excess. After an induction period, a slow precipitation of molybdic acid occurs for about 15 hours. The data obtained show the molybdenum solubility decreases with increasing aluminium concentration. The solubility law follows an exponential relation around 40 g/L of aluminium with a high determination coefficient. Molybdenum solubility is not impacted by the presence of gadolinium, or by an increasing concentration of uranium. (authors)

Demonstration and evaluation of dual-fuel technology; Demonstration och utvaerdering av dual-fuel-tekniken

Energy Technology Data Exchange (ETDEWEB)

Staalhammar, Per; Erlandsson, Lennart; Willner, Kristina (AVL MTC Motortestcenter AB (Sweden)); Johannesson, Staffan (Ecoplan AB (Sweden))

2011-06-15

There is an increased interest for Dual Fuel (methane-Diesel) applications in Sweden since this technology is seen as one of the more interesting options for a fast and cost effective introduction of biomethane as fuel for HD engines. The Dual Fuel technology has been used for many years, mainly for stationary purpose (generators, pumps and ships) while the Spark Ignited (SI) 'Otto' technology has been used for trucks and busses. One obstacle for introducing Dual Fuel technology for busses and trucks is the EU legislation that don't allow for HD on road certification of Dual Fuel applications. Challenges with the Dual Fuel technology is to develop cost effective applications that is capable of reaching low emissions (especially CH{sub 4} and NO{sub x}) in combination with high Diesel replacement in the test cycles used for on road applications. AVL MTC Motortestcenter AB (hereinafter called AVL) has on commission by SGC (Swedish Gas technical Centre) carried out this project with the objectives to analyze the Dual Fuel (Diesel-methane) technology with focus on emissions, fuel consumption and technical challenges. One important part of this project was to carry out emission tests on selected Dual Fuel applications in Sweden and to compile experiences from existing Dual Fuel technology. This report also summarizes other commonly used technologies for methane engines and compares the Dual Fuel with conventional Diesel and Otto technologies. The major challenges with Dual Fuel applications for on road vehicles will be to develop robust and cost effective solutions that meet the emission legislations (with aged catalysts) and to increase the Diesel replacement to achieve reasonable reduction of green house gases (GHG). This is especially important when biomethane is available as fuel but not Bio-Diesel. It will probably be possible to reach EURO V emission limits with advanced Dual Fuel systems but none of the tested systems reached EURO V emission levels

Operational results of WWER fuel fabricated by MSZ (Elektrostal, Russia)

International Nuclear Information System (INIS)

Asatiani, I.; Balabanov, S.; Beglov, A.; Khryashchev, D.

2009-01-01

The presentation brings forth a statistical analysis of the WWER fuel manufactured by OAO MSZ, operational experience. A necessity of such an analysis is determined by the fact that objective operational results prove the appropriateness of the solutions and decisions made by vendor, designer, manufacturer and utility, as well as motivates further fuel improvements. (authors)

Fuel cell added value for early market applications

Science.gov (United States)

Hardman, Scott; Chandan, Amrit; Steinberger-Wilckens, Robert

2015-08-01

Fuel Cells are often considered in the market place as just power providers. Whilst fuel cells do provide power, there are additional beneficial characteristics that should be highlighted to consumers. Due to the high price premiums associated with fuel cells, added value features need to be exploited in order to make them more appealing and increase unit sales and market penetration. This paper looks at the approach taken by two companies to sell high value fuel cells to niche markets. The first, SFC Energy, has a proven track record selling fuel cell power providers. The second, Bloom Energy, is making significant progress in the US by having sold its Energy Server to more than 40 corporations including Wal-Mart, Staples, Google, eBay and Apple. Further to these current markets, two prospective added value applications for fuel cells are discussed. These are fuel cells for aircraft APUs and fuel cells for fire prevention. These two existing markets and two future markets highlight that fuel cells are not just power providers. Rather, they can be used as solutions to many needs, thus being more cost effective by replacing a number of incumbent systems at the same time.

The cascad spent fuel dry storage facility

International Nuclear Information System (INIS)

Guay, P.; Bonnet, C.

1991-01-01

France has a wide variety of experimental spent fuels different from LWR spent fuel discharged from commercial reactors. Reprocessing such fuels would thus require the development and construction of special facilities. The French Atomic Energy Commission (CEA) has consequently opted for long-term interim storage of these spent fuels over a period of 50 years. Comparative studies of different storage concepts have been conducted on the basis of safety (mainly containment barriers and cooling), economic, modular design and operating flexibility criteria. These studies have shown that dry storage in a concrete vault cooled by natural convection is the best solution. A research and development program including theoretical investigations and mock-up tests confirmed the feasibility of cooling by natural convection and the validity of design rules applied for fuel storage. A facility called CASCAD was built at the CEA's Cadarache Nuclear Research Center, where it has been operational since mid-1990. This paper describes the CASCAD facility and indicates how its concept can be applied to storage of LWR fuel assemblies

Materials in the environment of the fuel in dry storage

Energy Technology Data Exchange (ETDEWEB)

Issard, H [TN International (Cogema Logistics) (France)

2012-07-01

Spent nuclear fuel has been stored safely in pools or dry systems in over 30 countries. The majority of IAEA Member States have not yet decided upon the ultimate disposition of their spent nuclear fuel: reprocessing or direct disposal. Interim storage is the current solution for these countries. For developing the technological knowledge data base, a continuation of the IAEA's spent fuel storage performance assessment was achieved. The objectives are: Investigate the dry storage systems and gather basic fuel behaviour assessment; Gather data on dry storage environment and cask materials; Evaluate long term behaviour of cask materials.

The influence of near field hydrogen on actinide solubilities and spent fuel leaching

International Nuclear Information System (INIS)

Spahiu, K.; Werme, L.; Eklund, U.B.

2000-01-01

Large amounts of hydrogen are produced as a result of the anoxic corrosion of iron in the proposed container materials for some geologic repositories. Another hydrogen source, less important than the anoxic corrosion of iron, is the radiolysis of water by the spent fuel radiation. Gas phase formation occurs when the pressure of the hydrogen equals at least the hydrostatic pressure, around 5 MPa at 500 meters depth. The effects of 5 MPa hydrogen pressure on spent PWR fuel leaching and on uranium oxide solubility have been studied in carbonated solutions at 70 C. The experiments were performed in a 1 liter autoclave, filled with 950 ml of a solution 10 mM NaCl, 2 mM NaHCO 3 and with hydrogen at a pressure of 5 MPa in the remaining 50 ml free volume. The leaching behavior of 2 g PWR spent fuel powder of the 0.25-0.50 mm fraction, placed in a gold basket was studied during several months by analyzing 10 ml solution samples taken after regular time intervals. A few experiments were performed also with unirradiated U(IV) oxide. In both cases extremely low concentrations of uranium (less than 10 -9 M) were measured in the solution samples. Furthermore the uranium levels in solution remained practically constant during the whole leaching period (more than one year), indicating the absence of any oxidative dissolution of the spent fuel matrix. The same conclusion is confirmed by the constant (within analytical errors) levels of strontium, cesium, molybdenum, iodine and technetium during the whole leaching period. These results have been compared with the ones obtained during the leaching of a spent fuel pin in anoxic conditions, where the uranium and other radionuclides levels are several orders of magnitude higher. The surface of spent fuel or U(IV) oxide is partially oxidized during storage, giving rise to relatively high levels of U(VI) in solution even during leaching in anoxic conditions. No such effect could be observed in the presence of 5 MPa hydrogen, indicating

LEU fuel cycle analyses for the Belgian BR2 Research Reactor

International Nuclear Information System (INIS)

Deen, J.R.; Snelgrove, J.L.

1988-01-01

Equilibrium fuel cycle characteristics were calculated for reference HEU and two proposed LEU fuel cycles using an 11-group diffusion-theory neutron flux solution in hexagonal-Z geometry. The diffusion theory model was benchmarked with a detailed Monte Carlo core model. The two proposed LEU fuel designs increased the 235 U loading 20% and the fuel meat volume 51%. The first LEU design used 10 B as a burnable absorber. Either proposed LEU fuel element would provide equilibrium fuel cycle characteristics similar to those of the HEU fuel cycle. Irradiation rates of Co control followers and Ir disks in the center of the core were reduced 6 ± 1% in the LEU equilibrium core compared to reference HEU core. 11 refs., 4 figs., 5 tabs

Fuel System Compatibility Issues for Prometheus-1

International Nuclear Information System (INIS)

DC-- Noe; KB Gibbard; MH Krohn