The Status of the Pik Reactor

Total Page:16

File Type:pdf, Size:1020Kb

The Status of the Pik Reactor XA04C1623 THE STATUS OF THE PIK REACTOR Yu. V. Petrov ACADEMY OF SCIENCES OF RUSSIA PETERSBURG NUCLEAR PHYSICS INSTITUTE on leave at: Technische Universitit Miinchen, Physik Department E18 D8046 Garching, Germany May 18,1992 Abstract This report describes the 100 MW research reactor PIK which is now under construction. The thermal neutron flux in the heavy water reflector exceeds 1015 CM-2S-1 ; in the light water trap, it is about 4 - 015 cm -23-1 . The replaceable core vessel allows to vary the parameters of the core over a wide range. The reactor provides sour- ces of hot, cold and ultracold eutrons for 10 horizontal, 6 inclined neutron beams, and neutron guides. At the ends of the beam tubes, the neutron flux is 101 _ loll -1-28-1. The flux of the long wave neutrons exceeds 109 M-2S-1 . To ensure precise measurements, the experimental hall is protected against vibrations. The poject meets all modern safety requirements. The calculated parameters of the reactor were verified using a full-scale mock-up. Seventy percent of the reactor construction ad installation were completed i te be- ginning of 1992. Version of the preprint: A.N.Erykalov, O.A.Kolesnicbenko, K.A.Konoplev, V.A.-Nazarenko, Yu.V.Petrov, S.L.Smolsky: PIK Reactor, PNPI-1784, St. Petersburg 1992 1 I The airns of the reactor 45 k7n south fom St. Petersburg and 4 m from te town of Gatchina, the high flux research reactor PIK [1 - 4 is being constructed. Fig.1 shows a drawing of the reactor building, and Fg.2 shows the building site in au- tumn 1991. The reactor is designed for a broad range of research in nuclear and solid state physics, for studying the basic properties of matter, e.g.. of newly developed materials, including high-temperature superconductors, for radiobiological research and also for solving many applied technical po- blerns. The envisaged hh flux of thermal., cold and hot neutrons permits to plan the investigation of basic neutron characteristics such as the electric and magnetic dipole moments, charge, life time and to study the fundamen- tal neutrons interactions, e.g., strong interactions in neutron collisions, and weak interactions after neutron capture. The reactor allows to develop independent sources of neutrinos and an- tineutrinos (- 10" Is) with known spectra: this can contribute to the development of neutrino physics. The high flux of thermal neutrons and the low background of fast neutrons and 7-quanta permit to continue the traditional research in nuclear physics, including and spectroscopy and various experiments with polarized neutrons and targets. Solid state physics will be represented by studies of the kinetics of non- systems, by neutronographic research on hgh-temperature su- perconductors, ceramics and new materials, and also y structural research on magnetic materials etc. The research in biology will include neutron and structural analysis of biological objects, studies of membranes etc. A more detailed description of the experimental program is gven in ref. [5]. The experimental program will be carried out in co-operation with the leading scientific research centers in Russia and abroad. The project of the reactor supervised by B.P.Konstantinov. Petersburg Nuclear Physics Institute of the Academy of Sciences of Russia, is being realized bv the Scientific Research Institute for Power Reactor Design and by other organizations of the State Committee for Atomic Energy. 2 2 Reactor design and neutron parameters The design and parameters of the PIK reactor were chosen so as to provide the maximum number and minimum cost of events in the experimental detectors 6,7]. The actual technological and heat transfer limitations were observed. The light water core with a volume of about 50 is placed in a heavy water reflector and serves as an intense source of fast neutrons with a power of 100 MW (see Figs. 3 - 5). The hea-vy water reflector n which the fast neutrons are slowed down ives the best ratio of thermal neutron flux to power as compared to other moderators [1]. Due to the large dffusion length in D20(LDO I at 02% of H20) and to the considerable dimensions of the heavy water tank diameter 2.5m; height from 25 to 2.0m), the thermal flux is rather high at large distances from the core where the background of fast neutrons as well as that of / quanta is small (Fig.6). A reflector of this type makes it possible to displace and to replace experimental channels either before or after the reactor starting-up. This reflector is safe against radiation darnaaes. Accumulated tritium and hydrogen are removed by a special isotopic purification circuit, and therefore the tritium activity in the D20 does not exceed 01 TBq11 [8]. The reflector has its own MW heavy water cooling circuit which allows to maintain its temperature within the range from 50 to 601C. Light water is used as a cheap coolant in the core of the reactor. Light water as in-core moderator provides a small neutron migration length which permiits to design a compact core. The core with high pressure (up to MPa) and high energy release (about MW11 on the average) is separated by a double core vessel from the reflector where the thermal neutron flux is formed and where the pressure is low 0-3 Wa). Precautions are taken in case of damage of experimental channels. Thin membranes through which the neutrons can easily pass are installed at the output of te heavy water tank to prevent the penetration of radioactivity into the experimental hall. A water pool of 12 -M depth protects of the staff from possible damages of the circuits. To prevent the contamination of the hall, ventilation is provided above the water surface. The vertical cylindrical core vessel serves as internal wall of the reflector tank and is connected to the water supply tubes that it can be replaced without affecting the tank itself. Owing to these measures, the PIK will 3 be a versatile unit permitting to change the arrangement and dimensions of the core even after the reactor is put in operation. Every to years when te core vessel is replaced because of the radiation dairiages, it is possible f necessary) to change the type of the fuel elements or even to install special experimental facilities inside the core. In the beginning of the PIK exploitation, the core vessel will be made of austenitic steel which has sufficient viscosity to prevent the vessel from cracking. Later on, this vessel w'II be replaced by an aluminum or zconium vessel. In order to ensure the high -flux of neutrons in the reflector and the light water trap, the fuel elements of the reactor should provide a high neutron multiplication factor . The fuel elements should also ensure a high spe- 'fic power to obtain a hgh absolute neutron flux. Tese requirements are met oing to the high density of fuel 90% enriched 115U with average den- sity 40 g1l) and owing to the increase of the specific heat transfer surface (6.5 m,/cm'). The fuel elements of the PIK reactor are twisted rods with crosslike section and an external diameter of 5.15 mm (see Fig. 5a). The twisting around the axis with a thread-spacing of 300 mm ensures a fixed distance between the fuel elements inside the bundle. The steel cladding of the fuel element is 0.15 'mm, the fuel loading is 714 ... U, and the meat density is - 22 `Ulcm'. The fuel elements are placed into a triangular lattice with a spacing of 523 mm iside the fuel assembly. The core is for- med by 12 hexagonal and 6 square fuel cassettes (Fig.5). The hexagonal fuel cassette contains 241 fuel elements, the square cassette contains 61 elements. The fuel elements were tested at 75 MW/1 core power density (see also 9 The neutron parameters of the reactor with the above fuel elements are shown in Fg.6 and are tabulated in Table . For longer terms it is planned to use aluminum fuel elements providing a higher neutron flux [10]. The control and safety system consists of a central control unit and rods in the reflector. The central unit (so-called "shutter") is made of two 'de rngs embracing the central light water trap and absorbing neutrons. In order to aoid asymmetrical distortion of the neutron flux. the rings are simultaneously moved apart from the central reactor plane. This system will compensate the burn-up and provide automatic control and emergency protection. Both halves of the central control unit normally have a clearance permitting quick emergency input of not less than 05 Of f 0.35 s. The absorber rods a-re realized as rectangular cassettes located in 4 the heavv water reflector ad containing europium oxide. Some of the rods serve as safety rods, the others are used as starting absorbents. The lateral shielding of the reactor is divided into biological and "expe- rimental' shielding. The bological shielding consists of iron, water (0.5 m), and heavv concrete 0-9 ro., 3.6 g/c7773). It diminishes the radiation to a level permitting attendance of the equipn-ient when te reactor is stopped. The experimental shielding I.Orn thick is part of the physical instruments and consists of movable units. The shielding reduces the reactor radiation to 14 vlh, i.e., half of the limit permitted b te existing standards. The reflector tank is located 9 m deep in the pool. The pool com- municates with the operating hall situated on the top floor of the reactor building. The experimental hall, into wich the neutron eams are guided, is separated from the operating hall (Fig.7).
Recommended publications
  • The Jules Horowitz Reactor Project, a Driver for Revival of the Research Reactor Community
    THE JULES HOROWITZ REACTOR PROJECT, A DRIVER FOR REVIVAL OF THE RESEARCH REACTOR COMMUNITY P. PERE, C. CAVAILLER, C. PASCAL AREVA TA CEA Cadarache - Etablissement d'AREVA TA - Chantier RJH - MOE - BV2 - BP n° 9 – 13115 Saint Paul lez Durance - France CS 50497 - 1100, rue JR Gauthier de la Lauzière, 13593 Aix en Provence cedex 3 – France ABSTRACT The first concrete of the nuclear island for the Jules Horowitz Reactor (JHR) was poured at the end of July 2009 and construction is ongoing. The JHR is the largest new platform for irradiation experiments supporting Generation II and III reactors, Generation IV technologies, and radioisotope production. This facility, composed of a unique grouping of workshops, hot cells and hot laboratories together with a first -rate MTR research reactor, will ensure that the process, from preparations for irradiation experiments through post-irradiation non-destructive examination, is completed expediently, efficiently and, of course, safely. In addition to the performance requirements to be met in terms of neutron fluxes on the samples (5x1014 n.cm-2/sec-1 E> 1 MeV in core and 3,6x1014 n.cm-2/sec-1 E<0.625 eV in the reflector) and the JHR’s considerable irradiation capabilities (more than 20 experiments and one-tenth of irradiation area for simultaneous radioisotope production), the JHR is the first MTR to be built since the end of the 1960s, making this an especially challenging project. The presentation will provide an overview of the reactor, hot cells and laboratories and an outline of the key milestones in the project schedule, including initial criticality in early 2014 and radioisotope production in 2015.
    [Show full text]
  • Decommissioning of Nuclear Facilities in Switzerland – Lessons Learned
    WIR SCHAFFEN WISSEN – HEUTE FÜR MORGEN Fritz Leibundgut :: Decommissioning Officer :: Paul Scherrer Institut Decommissioning of Nuclear Facilities in Switzerland – Lessons learned HRP/IAEA/NEA Decommissioning workshop – February 7, 2017 Overview Basel Germany Aarau/Bern Zürich material sciences nanotechnology radio chemistry hotlab radio pharmacy biology PSI east solar concentrator energy research SwissFEL particle physics proton accelerator neutron source muon source proton therapy PSI west synchrotron light source Page 2 Nuclear installations on the PSI area • (ZWILAG) • AERA with VVA* • Hotlabor • DIORIT* • SAPHIR* • PROTEUS* *Post-operation phase/ Decomm./Dismantling Page 3 SAPHIR: 1957-1993 First reactor in Switzerland; used for isotope production, reactor training, neutron source for various experiments 1955 USA exposed a reactor at the “Atoms for Peace” conference in Geneva 1956 Laying of the cornerstone in Würenlingen 1957 First criticality 1960 Approval by Swiss government 1985 Approval for 10 MW 1993 Final shutdown 2000 Decommissioning ordinance 2008 Dismantling of the pool completed 2015 Cleanout of the KBL (“Kernbrennstofflager”) Page 4 SAPHIR: Status 2016 ENSI-Inspection at 7. of April, 2016 Page 5 DIORIT: 1960-1977 Proprietary Swiss development. Goal was the construction of industrial applicable reactors for material testings and experiments. 1960 Operation with natural uranium and D2O as coolant and moderator. 1966 Uprating from 20 MW to 30 MW. 1972 (after modification): Operation with LEU. 1977 Final shutdown. 1982 Partial dismantling; continued 1988-1993. 1994 Approval of dismantling the reactor. 2005 Asbestos was found interruption until 2009. 2013 Dismantling of biological shielding 2016 Cutting of the „Arbeitsboden“ (22 t activated Fe) 2019 (?) 2. Decommissioning ordinance for greenfield Page 6 DIORIT PSI, 23.10.2016 Page 7 Biol.
    [Show full text]
  • German Research Reactor
    German Research Reactor Back-end Provisions RERTR 2002 San Carlos de Bariloche, Argentina Nov-3/8 Authors: Siegfried Koester/German Federal Ministry of Economics and Technology Gerhard Gruber/RWE NUKEM GmbH On behalf of the German Working Group Back-end for Research Reactors Fuel Cycle History of Half a Century US 'Atoms for Peace Program', President Eisenhower 1953 HEU for peaceful research and development (R&D) First RR built in Germany in the late 1950s US supplied fuel on a lease basis until 1974 Until 1987 fuel sale with option to return spent HEU + LEU fuel 1987-Dec-31: DOE's policy for receipt of FRR SNF expires without prior notice German RR Back-end History 1960s: US Reprocessing, no return of waste 1960/70s: UK Reprocessing, no return of waste 1970s: Belgium + France Reprocessing, no return of waste 1980s: US Reprocessing, no return of waste 1990s: UK Reprocessing, mandatory waste return Current German Back-end Solution 1996 - 2006: Return SNF to US under 'FRR SNF Return Policy' (US-origin) Non-Proliferation: Return of all HEU to the US 2 Promote RR conversion to LEU 10 yrs to provide for national Back-end solutions Establish int. Back-end solutions (e.g. IAEA promotion) German Spent RR Fuel Output Current Reactors (operation time): 'BER-II' (2015), 'FRG-1' (> 2010), 'FRJ-2' (2005?), 'TRIGA-MZ' (>2010), 8 'SUR’ Future Reactors: 'FRM-II' (2003-2033), 'NN' (possibly needed > 2010) Fuels: U-Al, U-Si, U-ZrH, U-PE, U-Mo in future US- and RUS-origin RUS-origin: 'FRM-II' + 'RFR' (shut down) with 1,000 FE leftover
    [Show full text]
  • Institute for Nuclear Research and Nuclear Energy Bulgarian Academy of Sciences
    Institute for Nuclear Research and Nuclear Energy Bulgarian Academy of Sciences 20102010 Present State Future Prospects Short History The Physical Institute of the Bulgarian Academy of Sciences (BAS) was established on 1 July 1946 by academician Georgi Nadjakov who became its first director. JINR, Dubna, was established on 26 March 1956 Acad. G. Nadjakov was signing the Protocol together with 10 representatives of other countries. In the autumn of 1955 the Bulgarian government took a decision to build a research nuclear reactor. In 1962 the Physical Institute of BAS was renamed as the Physical Institute with a Nuclear Experimental Facility. In 1972 it was splited into Institute for Nuclear Research and Nuclear Energy (INRNE) and Institute of Solid State Physics. Mission The Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences is the biggest leading complex centre in Bulgaria for scientific research and applications of the nuclear science and technologies and studies of their interactions with the environment. Vision INRNE guarantees a high quality performance of research and innovation activities, addressed to support important national programs, keeping abreast with the modern scientific achievements. With its long standing experience and active collaboration with leading European and International institutions, INRNE contributes to the progress of the physical science. Since 2003/2004 INRNE BAS is certificated ISO 9001:2000 №3312/0 according to ISO 14001:2004 №357/0 Staff and Budget 14 74 126
    [Show full text]
  • Treatment of Spent Fuels from Research Reactors and Reactor Development Programs in Germany
    TREATMENT OF SPENT FUELS FROM RESEARCH REACTORS AND REACTOR DEVELOPMENT PROGRAMS IN GERMANY K.D. CLOSS XA9949808 Forschungszentrum Karlsruhe, Karlsruhe, Germany Abstract Quite a great number of different types of spent fuel from research reactors and development programs exists in Germany. The general policy is to send back to the USA as long as possible fuel from MTRs and TRIG As of USA origin. An option is reprocessing in Great Britain or France. This option is pursued as long as reprocessing and reuse of the recovered material is economically justifiable. For those fuels which cannot be returned to the USA or which will not be reprocessed, a domestic back-up solution of spent fuel management has been developed in Germany, compatible with the management of spent fuel from power reactors. It consists in dry storage in special casks and, later on, direct disposal. Preliminary results from experimental R&D inves- tigations with research reactor fuel and experience from LWR fuel lead to the conclusion that the direct dis- posal option even for research reactor fuel or exotic fuel does not impose major technical difficulties for the German waste management and disposal concept. 1. RESEARCH AND EXPERIMENTAL REACTORS IN GERMANY At the end of 1997, six research reactors with a power > 100 kW were operating in Germany. These comprise two TRIGA-type reactors, three swimming-pool reactors and one DIDO-type reactor. Moreover, one new research reactor is under construction, the operational start-up of which is expected in 2001. More details of these reactors are given in Table I. In addition to these reactors, there are eight research reactors permanently shut down, some of which have already been dismantled.
    [Show full text]
  • Neutrons for the Nation Discovery and Applications While Minimizing the Risk of Nuclear Proliferation
    Neutrons for the Nation Discovery and Applications while Minimizing the Risk of Nuclear Proliferation A Report by the APS Panel on Public Affairs July 2018 ABOUT APS & POPA AUTHORSHIP Founded in 1899 to advance and diffuse the knowledge of The American Physical Society has sole responsibility for physics, the American Physical Society (APS) is now the nation’s the contents of this report, and the questions, findings, and leading organization of physicists with approximately 55,000 recommendations within. members in academia, national laboratories and industry. APS has long played an active role in the federal government; its members serve in Congress and have held positions such as Science Advisor to the President of the United States, Director ACKNOWLEDGEMENTS of the CIA, Director of the National Science Foundation and We thank Frank Bates, Bill Buyers, David Dean, Alex Glaser, Secretary of Energy. Geoff Greene, Jenny Heimberg, Mark Johnson, John Katsaras, Julia Kornfield, Patrick Lemoine, Dan Neumann, Sean O’Kelly, This report was overseen by the APS Panel on Public Affairs Ray Orbach, Winfried Petry, Roger Pynn, Kate Ross, and (POPA). POPA routinely produces reports on timely topics J. Michael Rowe for their contributions to this report. being debated in government so as to inform the debate with the perspectives of physicists working in the relevant issue areas. PUBLICATION DATE: JULY 2018 REPORT COMMITTEE American Physical Society James Wells, Co-Chair, University of Michigan Physics This report is available under the terms of a Creative Commons Department Attribution 4.0 International License. Sharing and adapting the material for any purpose, even commercial, does not require Julia Phillips, Co-Chair, Sandia National Laboratory prior written permission.
    [Show full text]
  • Assessment of Missions and Requirements for a New U.S. Test Reactor
    Nuclear Energy Advisory Committee Assessment of Missions and Requirements for a New U.S. Test Reactor Draft Report December 2016 i Table of Contents ii Acronyms ANL Argonne National Laboratory ANSTO Australian Nuclear Science and Technology Organisation ATR Advanced Test Reactor BARC Bhabha Atomic Research Centre CAEA China Atomic Energy Authority CEA Commissariat à l’Energie Atomique et aux Energies Alternatives CNEA National Atomic Energy Commission DOD Department of Defense DOE Department of Energy DOE-NE Department of Energy -Office of Nuclear Energy dpa displacements per atom ESAAB Energy Systems Acquisition Advisory Board EBR-II Experimental Breeder Reactor-II GCR Gas-Cooled Reactor GIF Generation IV International Forum FFTF Fast Flux Test Facility FHR Fluoride Salt-Cooled High Temperature Reactor HFIR High Flux Isotope Reactor HTGR High Temperature Gas-cooled reactors HTR-PM High Temperature gas-cooled Reactor Pebble-bed Module IFE Institute for Energy Technology IGCAR Indira Gandhi Centre for Atomic Research IKET Institute for Nuclear and Energy Technologies ININ Instituto Nacional de Investigaciones Nucleare INL Idaho National Laboratory JAEA Japan Atomic Energy Agency (JAEA) KAERI Korea Atomic Energy Research Institute KIT Karlsruhe Institute of Technology LANL Los Alamos National Laboratory LWR Light Water Reactor iii LFR Lead Fast Reactor MITR Massachusetts Institute of Technology Research Reactor MOST Ministry of Science and Technology MSR Molten Salt Reactor MTR Material Test Reactor NAS National Academy of Science NBSR National Bureau of Standards Reactor NEAC Nuclear Energy Advisory Committee NEI Nuclear Energy Institute NRT SC Nuclear Reactor Technology Subcommittee NASA National Aeronautics and Space Administration NNSA National Nuclear Security Administration NRC U.S.
    [Show full text]
  • A National Strategy for Materials Research with Neutron Beams
    DRAFT FOR CONSULTATION A National Strategy for Materials Research with Neutron Beams A discussion paper for the Roundtable Meeting, “Canadian Neutron Initiative: Towards a National Neutron Strategy” To be held as a virtual event, December 15–16, 2020 Updated Dec 10, 2020 1 DRAFT FOR CONSULTATION This Canadian Neutron Initiative (CNI) discussion paper and associated Roundtable Meeting are produced in partnership with CIFAR. We also thank the following sponsors: 2 DRAFT FOR CONSULTATION Contents 1 Executive summary and overview of a national strategy ..................................................................... 5 2 Consultation on the strategy ................................................................................................................ 9 3 The present: A strong foundation for continued excellence .............................................................. 12 3.1 The Canadian neutron beam user community ........................................................................... 12 3.2 McMaster University ................................................................................................................... 16 3.3 Other neutron beam capabilities and interests .......................................................................... 17 4 Forging foreign partnerships ............................................................................................................... 19 4.1 Global renewal of advanced neutron sources ...........................................................................
    [Show full text]
  • The Research Reactor Irt-Sofia: 50 Years After First Criticality
    E4 THE RESEARCH REACTOR IRT-SOFIA: 50 YEARS AFTER FIRST CRITICALITY K. KREZHOV International Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Sofia, Bulgaria Abstract The design features of the research reactor IRT-2000 in Sofia and accumulated experience in the past prior to the partial dismantling of obsolete reactor systems are outlined. The present status of the ongoing refurbishment to a low power reactor IRT-200 and its planned utilization are briefly described. 1. INTRODUCTION Since early 1956, the Bulgarian government has officially favored the use of nuclear power. In 1957 Bulgaria ratified the Statute of the IAEA and became one of the IAEA states- founders. In June 1957 the Committee for Peaceful Use of Atomic Energy (CPUAE) within the Council of Ministers was established as the specialized state body to promote the nuclear research and applications as well as to control and coordinate the related activities in industry, agriculture, medicine and science. In support to this program the research reactor (RR) IRT- Sofia was contracted. The initial construction of a reactor of the same WWR type as in Poland, Czechoslovakia, Hungary and Rumania that started in 1956 was adapted for the IRT- type of reactor designed and constructed from 1957 to 1961 by the Kurchatov Institute, Moscow. The first chain reaction was accomplished at 20:15 h on September 18, 1961. The official inauguration took place on November 9, 1961. The Reactor underwent several upgrades from initial 500 kW: 1000 kW (1962), 1500 kW (1965) and 2000 kW (IRT-2000) in 1970. The reactor was operated safely with a mixed (LEU-HEU) core for 28 years at power levels agreed upon user demands up to 2000 kW.
    [Show full text]
  • IAEA Nuclear Energy Series Applications of Research Reactors No
    IAEA Nuclear Energy Series IAEA Nuclear No. NP-T-5.3 No. IAEA Nuclear Energy Series Applications of Research Reactors No. NP-T-5.3 Basic Applications of Principles Research Reactors Objectives Guides Technical Reports INTERNATIONAL ATOMIC ENERGY AGENCY VIENNA ISBN 978–92–0–145010–4 ISSN 1995–7807 13-49091_PUB1627_cover_A4.indd 1,3 2014-02-27 08:47:02 IAEA NUCLEAR ENERGY SERIES PUBLICATIONS STRUCTURE OF THE IAEA NUCLEAR ENERGY SERIES Under the terms of Articles III.A and VIII.C of its Statute, the IAEA is authorized to foster the exchange of scientific and technical information on the peaceful uses of atomic energy. The publications in the IAEA Nuclear Energy Series provide information in the areas of nuclear power, nuclear fuel cycle, radioactive waste management and decommissioning, and on general issues that are relevant to all of the above mentioned areas. The structure of the IAEA Nuclear Energy Series comprises three levels: 1 — Basic Principles and Objectives; 2 — Guides; and 3 — Technical Reports. The Nuclear Energy Basic Principles publication describes the rationale and vision for the peaceful uses of nuclear energy. Nuclear Energy Series Objectives publications explain the expectations to be met in various areas at different stages of implementation. Nuclear Energy Series Guides provide high level guidance on how to achieve the objectives related to the various topics and areas involving the peaceful uses of nuclear energy. Nuclear Energy Series Technical Reports provide additional, more detailed information on activities related to the various areas dealt with in the IAEA Nuclear Energy Series. The IAEA Nuclear Energy Series publications are coded as follows: NG — general; NP — nuclear power; NF — nuclear fuel; NW — radioactive waste management and decommissioning.
    [Show full text]
  • Supplement Analysis for the Foreign Research Reactor Spent Nuclear Fuel Acceptance Program
    DOE/EIS-0218-SA-8 SUPPLEMENT ANALYSIS FOR THE FOREIGN RESEARCH REACTOR SPENT NUCLEAR FUEL ACCEPTANCE PROGRAM APRIL 2019 \?f1l ~ : ~ National Nuclear Security Administration U.S. Department of Energy National Nuclear Security Administration Washington, DC Supplement Analysis for the Foreign Research Reactor Spent Nuclear Fuel Acceptance Program TABLE OF CONTENTS Page 1.0 INTRODUCTION AND BACKGROUND ........................................................................................... 1 1.1 Policy on Exemptions ..... ................................................ .... .................................................... 2 1.2 Statement of Intent Between the United States and Japan .................. .. .................... ......... 3 1.3 HEU Shipments ..... .. ............................................................................................................... 3 1.4 Training Research Isotope General Atomics (TRIGA) Fuel .................................... ................ 4 2.0 PURPOSE AND NEED, AND PROPOSED ACTION ............................................................................ 4 2.1 Purpose and Need .................................................... ...................... ....................................... 4 2.2 Proposed Action ............ .. ...................... ....................................................................... .. .... ... 4 2.3 Description of Activities ......................................................................................................... 4 3.0 AFFECTED
    [Show full text]
  • Low Dimensional Neutron Moderators for Enhanced Source Brightness
    Low dimensional neutron moderators for enhanced source brightness Ferenc Mezei 1,2 , Luca Zanini 1, Alan Takibayev 1, Konstantin Batkov 1, Esben Klinkby 1,3 , Eric Pitcher 1 and Troels Sch önfeldt 1,3 1European Spallation Source, ESS AB, PO BOX 176, 22100 Lund, Sweden 2Hungarian Academy of Sciences, Wigner RCF, 1525 Budapest, Pf. 49, Hungary 3DTU Nutech, Technical University of Denmark, DTU Risø Campus, 4000 Roskilde, Denmark Corresponding Author: F. Mezei, European Spallation Source ESS AB, PO BOX 176, 22100 Lund, Sweden, e-mail: [email protected] , Tel:+46 72 179 2039 Abstract In a recent numerical optimization study we have found that liquid para-hydrogen coupled cold neutron moderators deliver 3 – 5 times higher cold neutron brightness at a spallation neutron source if they take the form of a flat, quasi 2-dimensional disc, in contrast to the conventional more voluminous shapes used by now. In the present paper we describe a simple theoretical explanation of this unexpected behavior, which is based on the large difference in para-hydrogen between the values of the scattering mean free path for thermal neutrons (in the range of 1 cm) and its much larger equivalent for cold neutrons. This model leads to the conclusions that the optimal shape for high brightness para- hydrogen neutron moderators is the quasi 1-dimensional tube and these low dimensional moderators can also deliver much enhanced cold neutron brightness in fission reactor neutron sources, compared to much more voluminous liquid D 2 or H 2 moderators currently used. Neutronic simulation calculations confirm both of these theoretical conclusions.
    [Show full text]