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TECHNIQUES FOR MONITORING PLUTONIUM IN THE ENVIRONMENT

Description: Plutonium is one of the principal materials of both commercial and military nuclear power. It is produced primarily in fission reactors that contain uranium fuel, and its importance arises from the fact that a large portion of the plutonium produced is fissile: like uranium 235, the mass 239 and 241 isotopes of plutonium can be caused to fission by neutrons, including those with low energy. Because such fission events also release neutrons, substantial amounts of energy can be extracted from plutonium in a controlled or an explosive nuclear chain reaction. Now that commercial nuclear reactors provide a noticeable fraction of United States (and world) electrical energy, these reactors account for most plutonium production. For the most part, this material now remains in the irradiated fuel after removal from reactors, but should this fuel be reprocessed, the plutonium could be recycled to provide part and even most of the fissile content of fresh fuel. For the current generation of water-cooled reactors, the amount of plutonium to be recycled is substantial. In fast breeder reactors, designed to produce more fissile material than they destroy, considerably larger quantities of plutonium would be recycled. In other types of advanced reactors, particularly those which depend heavily on thorium as the material from which fissile material (primarily uranium 233) is produced, the amount of plutonium to be handled would be considerably reduced. Because plutonium is a highly toxic substance, great care is taken to contain it at the sites and facilities where it is stored or handled. In addition, it is necessary that devices be available to monitor any releases from these facilities into environmental media and to measure concentrations of plutonium in these media. The radiation protection standards are so strict for plutonium that only small releases and low concentrations can be tolerated. Such considerations, ...
Date: July 1, 1978
Creator: Nero, A. V., Jr.
Partner: UNT Libraries Government Documents Department

DAMAGE TO MITOCHONDRIAL ELECTRON TRANSPORT AND ENERGY COUPLING BY VISIBLE LIGHT

Description: Plutonium is one of the principal materials of both commercial and military nuclear power. It is produced primarily in fission reactors that contain uranium fuel, and its importance arises from the fact that a large portion of the plutonium produced is fissile: like uranium 235, the mass 239 and 241 isotopes of plutonium can be caused to fission by neutrons, including those with low energy. Because such fission events also release neutrons, substantial amounts of energy can be extracted from plutonium in a controlled or an explosive nuclear chain reaction. Now that commercial nuclear reactors provide a noticeable fraction of United States (and world) electrical energy, these reactors account for most plutonium production. For the most part, this material now remains in the irradiated fuel after removal from reactors, but should this fuel be reprocessed, the plutonium could be recycled to provide part and even most of the fissile content of fresh fuel. For the current generation of water-cooled reactors, the amount of plutonium to be recycled is substantial. In fast breeder reactors, designed to produce more fissile material than they destroy, considerably larger quantities of plutonium would be recycled. In other types of advanced reactors, particularly those which depend heavily on thorium as the material from which fissile material (primarily uranium 233) is produced, the amount of plutonium to be handled would be considerably reduced. Because plutonium is a highly toxic substance, great care is taken to contain it at the sites and facilities where it is stored or handled. In addition, it is necessary that devices be available to monitor any releases from these facilities into environmental media and to measure concentrations of plutonium in these media. The radiation protection standards are so strict for plutonium that only small releases and low concentrations can be tolerated. Such considerations, ...
Date: September 1, 1977
Creator: Aggarwal, B.B.; Quintanilha, A.T.; Cammack, R. & Packer, L.
Partner: UNT Libraries Government Documents Department

Compact, energy EFFICIENT neutron source: enabling technology for various applications

Description: A novel neutron source comprising of a deuterium beam (energy of about 100 KeV) injected into a tube filled with tritium gas and/or tritium plasma that generates D-T fusion reactions, whose products are 14.06 MeV neutrons and 3.52 MeV alpha particles, is described. At the opposite end of the tube, the energy of deuterium ions that did not interact is recovered. Beryllium walls of proper thickness can be utilized to absorb 14 MeV neutrons and release 2-3 low energy neutrons. Each ion source and tube forms a module. Larger systems can be formed from multiple units. Unlike currently proposed methods, where accelerator-based neutron sources are very expensive, large, and require large amounts of power for operation, this neutron source is compact, inexpensive, easy to test and to scale up. Among possible applications for this neutron source concept are sub-critical nuclear breeder reactors and transmutation of radioactive waste.
Date: December 1, 2009
Creator: Hershcovitch, A. & Roser, T.
Partner: UNT Libraries Government Documents Department

A Conceptual Design of a Thorium-Uranium (233) Power Breeder Reactor

Description: From abstract: A conceptual design study has been performed for a sodium cooled, graphite moderated, thermal power-breeder reactor utilizing the Thorium-Uranium 233 breeding cycle. Several aspects of the design of the system are considered but no attempt has been made to supply all the details. It appears that the design presented is feasible and will allow the production of economic power as well as full utilization of thorium resources.
Date: February 1, 1954
Creator: Henrie, J. O. & Weisner, E. F.
Partner: UNT Libraries Government Documents Department

THE DEACTIVATION DECONTAMINATION & DECOMMISSIONING OF THE PLUTONIUM FINISHING PLANT (PFP) A FORMER PLUTONIUM PROCESSING FACILITY AT DOE HANFORD SITE

Description: The Plutonium Finishing Plant (PFP) was constructed as part of the Manhattan Project during World War II. The Manhattan Project was developed to usher in the use of nuclear weapons to end the war. The primary mission of the PFP was to provide plutonium used as special nuclear material (SNM) for fabrication of nuclear devices for the war effort. Subsequent to the end of World War II, the PFP's mission expanded to support the Cold War effort through plutonium production during the nuclear arms race and later the processing of fuel grade mixed plutonium-uranium oxide to support DOE's breeder reactor program. In October 1990, at the close of the production mission for PFP, a shutdown order was prepared by the Department of Energy (DOE) in Washington, DC and issued to the Richland DOE field office. Subsequent to the shutdown order, a team from the Defense Nuclear Facilities Safety Board (DNFSB) analyzed the hazards at PFP associated with the continued storage of certain forms of plutonium solutions and solids. The assessment identified many discrete actions that were required to stabilize the different plutonium forms into stable form and repackage the material in high integrity containers. These actions were technically complicated and completed as part of the PFP nuclear material stabilization project between 1995 and early 2005. The completion of the stabilization project was a necessary first step in deactivating PFP. During stabilization, DOE entered into negotiations with the U.S. Environmental Protection Agency (EPA) and the State of Washington and established milestones for the Deactivation and Decommissioning (D&D) of the PFP. The DOE and its contractor, Fluor Hanford (Fluor), have made great progress in deactivating, decontaminating and decommissioning the PFP at the Hanford Site as detailed in this paper. Background information covering the PFP D&D effort includes descriptions of negotiations with the ...
Date: February 1, 2006
Creator: CHARBONEAU, S.L.
Partner: UNT Libraries Government Documents Department

Treatment Method for Fermi Barrel Sodium Metal Residues

Description: Fermi barrels are 55-gallon drums that once contained bulk sodium metal from the shutdown Fermi 1 breeder reactor facility, and now contain residual sodium metal and other sodium/air reaction products. This report provides a residual sodium treatment method and proposed quality assurance steps that will ensure that all residual sodium is deactivated and removed from the Fermi barrels before disposal. The treatment method is the application of humidified carbon dioxide to the residual sodium followed by a water wash. The experimental application of the treatment method to six Fermi barrels is discussed, and recommendations are provided for further testing and evaluation of the method. Though more testing would allow for a greater refinement of the treatment technique, enough data has been gathered from the tests already performed to prove that 100% compliance with stated waste criteria can be achieved.
Date: June 1, 2005
Creator: Sherman, Steven R. & Knight, Collin J.
Partner: UNT Libraries Government Documents Department

Overview of Idaho National Laboratory's Hot Fuels Examination Facility

Description: The Hot Fuels Examination Facility (HFEF) at the Materials and Fuels Complex (MFC) of the Idaho National Laboratory was constructed in the 1960’s and opened for operation in the 1975 in support of the liquid metal fast breeder reactor research. Specifically the facility was designed to handle spent fuel and irradiated experiments from the Experimental Breeder Reactor EBRII, the Fast Flux Test Facility (FFTF), and the Transient Reactor Test Facility (TREAT). HFEF is a large alpha-gamma facility designed to remotely characterize highly radioactive materials. In the late 1980’s the facility also began support of the US DOE waste characterization including characterizing contact-handled transuranic (CH-TRU) waste. A description of the hot cell as well as some of its primary capabilities are discussed herein.
Date: September 1, 2007
Creator: Robinson, Adam B.; Lind, R. Paul & Wachs, Daniel M.
Partner: UNT Libraries Government Documents Department

Cadmium Depletion Impacts on Hardening Neutron6 Spectrum for Advanced Fuel Testing in ATR

Description: For transmuting long-lived isotopes contained in spent nuclear fuel into shorter-lived fission products effectively is in a fast neutron spectrum reactor. In the absence of a fast spectrum test reactor in the United States of America (USA), initial irradiation testing of candidate fuels can be performed in a thermal test reactor that has been modified to produce a test region with a hardened neutron spectrum. A test region is achieved with a Cadmium (Cd) filter which can harden the neutron spectrum to a spectrum similar (although still somewhat softer) to that of the liquid metal fast breeder reactor (LMFBR). A fuel test loop with a Cd-filter has been installed within the East Flux Trap (EFT) of the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). A detailed comparison analyses between the cadmium (Cd) filter hardened neutron spectrum in the ATR and the LMFBR fast neutron spectrum have been performed using MCWO. MCWO is a set of scripting tools that are used to couple the Monte Carlo transport code MCNP with the isotope depletion and buildup code ORIGEN-2.2. The MCWO-calculated results indicate that the Cd-filter can effectively flatten the Rim-Effect and reduce the linear heat rate (LHGR) to meet the advanced fuel testing project requirements at the beginning of irradiation (BOI). However, the filtering characteristics of Cd as a strong absorber quickly depletes over time, and the Cd-filter must be replaced for every two typical operating cycles within the EFT of the ATR. The designed Cd-filter can effectively depress the LHGR in experimental fuels and harden the neutron spectrum enough to adequately flatten the Rim Effect in the test region.
Date: May 1, 2011
Creator: Chang, Gray S.
Partner: UNT Libraries Government Documents Department

Fatigue Testing of Metallurgically-Bonded EBR-II Superheater Tubes

Description: Fatigue crack growth tests were performed on 2¼Cr-1Mo steel specimens machined from ex-service Experimental Breeder Reactor – II (EBR-II) superheater duplex tubes. The tubes had been metallurgically bonded with a 100 µm thick Ni interlayer; the specimens incorporated this bond layer. Tests were performed at room temperature in air and at 400°C in air and humid Ar; cracks were grown at varied levels of constant ?K. Crack growth tests at a range of ?K were also performed on specimens machined from the shell of the superheater. In all conditions the presence of the Ni interlayer was found to result in a net retardation of growth as the crack passed through the interlayer. The mechanism of retardation was identified as a disruption of crack planarity and uniformity after passing through the porous interlayer. Full crack arrest was only observed in a single test performed at near-threshold ?K level (12 MPa?m) at 400°C. In this case the crack tip was blunted by oxidation of the base steel at the steel-interlayer interface.
Date: December 1, 2006
Creator: Totemeier, Terry C.
Partner: UNT Libraries Government Documents Department

Decommissioning of Experimental Breeder Reactor - II Complex, Post Sodium Draining

Description: The Experimental Breeder Reactor - II (EBR-II) was shutdown in September 1994 as mandated by the United States Department of Energy. This sodium-cooled reactor had been in service since 1964. The bulk sodium was drained from the primary and secondary systems and processed. Residual sodium remaining in the systems after draining was converted into sodium bicarbonate using humid carbon dioxide. This technique was tested at Argonne National Laboratory in Illinois under controlled conditions, then demonstrated on a larger scale by treating residual sodium within the EBR-II secondary cooling system, followed by the primary tank. This process, terminated in 2002, was used to place a layer of sodium bicarbonate over all exposed surfaces of sodium. Treatment of the remaining EBR-II sodium is governed by the Resource Conservation and Recovery Act (RCRA). The Idaho Department of Environmental Quality issued a RCRA Operating Permit in 2002, mandating that all hazardous materials be removed from EBR-II within a 10 year period, with the ability to extend the permit and treatment period for another 10 years. A preliminary plan has been formulated to remove the remaining sodium and NaK from the primary and secondary systems using moist carbon dioxide, steam and nitrogen, and a water flush. The moist carbon dioxide treatment was resumed in May 2004. As of August 2005, approximately 60% of the residual sodium within the EBR-II primary tank had been treated. This process will continue through the end of 2005, when it is forecast that the process will become increasingly ineffective. At that time, subsequent treatment processes will be planned and initiated. It should be noted that the processes and anticipated costs associated with these processes are preliminary. Detailed engineering has not been performed, and approval for these methods has not been obtained from the regulator or the sponsors.
Date: September 1, 2005
Creator: Michelbacher, J. A. (Bart); Henslee, S. Paul; Knight, Collin J. & Sherman, Steven R.
Partner: UNT Libraries Government Documents Department

Strain-Rate Effects on Microstructural Deformation in Irradiated 316 SS

Description: A series of studies have been performed to investigate the post-irradiation deformation and failure behavior of 12% cold-worked 316 stainless steel following irradiation to variety of doses and temperatures in the outer rows of the experimental breeder reactor II (EBR-II). In the current phase of these studies, three sets of samples with different radiation induced microstructures have been characterized with transmission electron microscopy (TEM) following tensile testing to failure at a ‘fast’ strain-rate (1 x 10-3 s-1) and a ‘slow’ strain-rate (1 x 10-7 s-1). The samples were irradiated to doses between 9 and 41 dpa at temperatures between 383 and 443 degrees C. Tensile tests were conducted at a temperature of 430 degrees C and only regions outside of the necked region were examined. Over the parameters tested, strain-rate had a negligible effect on the deformation microstructure. In addition, there was no clear evidence of localized deformation behavior and the deformation appeared relatively homogeneous, characterized by unfaulting and incorporation of faulted dislocation loops into the general dislocation network structure. The influence of the defect microstructures and strain-rate on deformation behavior is discussed.
Date: February 1, 2005
Creator: Cole, James I.; Allen, Todd R.; Akasaka, Naoaki; Tsai, Hanchung; Yoshitake, Tsunemitsu; Yamagata, Ichiro et al.
Partner: UNT Libraries Government Documents Department

Technical Information on the Carbonation of the EBR-II Reactor, Summary Report Part 2: Application to EBR-II Primary Sodium System and Related Systems

Description: Residual sodium is defined as sodium metal that remains behind in pipes, vessels, and tanks after the bulk sodium metal has been melted and drained from such components. The residual sodium has the same chemical properties as bulk sodium, and differs from bulk sodium only in the thickness of the sodium deposit. Typically, sodium is considered residual when the thickness of the deposit is less than 5-6 cm. This residual sodium must be removed or deactivated when a pipe, vessel, system, or entire reactor is permanently taken out of service, in order to make the component or system safer and/or to comply with decontamination and decomissioning regulations. As an alternative to the established residual sodium deactivation techniques (steam-and-nitrogen, wet vapor nitrogen, etc.), a technique involving the use of moisture and carbon dioxide has been developed. With this technique, sodium metal is converted into sodium bicarbonate by reacting it with humid carbon dioxide. Hydrogen is emitted as a by-product. This technique was first developed in the laboratory by exposing sodium samples to humidifed carbon dioxide under controlled conditions, and then demonstrated on a larger scale by treating residual sodium within the Experimental Breeder Reactor II (EBR-II) secondary cooling system, followed by the primary cooling system, respectively. The EBR-II facility is located at the Idaho National Laboratory (INL) in southeastern Idaho, USA. This report is Part 2 of a two-part report. This second report provides a supplement to the first report and describes the application of the humdidified carbon dioxide technique ("carbonation") to the EBR-II primary tank, primary cover gas systems, and the intermediate heat exchanger. Future treatment plans are also provided.
Date: March 1, 2006
Creator: Sherman, Steven R. & Knight, Collin J.
Partner: UNT Libraries Government Documents Department