The influence of composition variations on long-term glass behavior was investigated for three nuclear glass composition domains: the French SON 68 (R7T7-type) glass, the Na Mg borosilicate AVM ...

For performance assessment of high-level radioactive waste disposal in salt formations, corrosion tests were carried out, using high active R7T7-type glass containing reprocessing waste, produced by CEA Marcoule. The objective of this investigation was to...

High-level nuclear waste containment glass is subjected to irradiation-induced stresses whose consequences must be assessed to guarantee the material behavior over time. Alpha decay from the minor actinides confined in the glass structure is responsible for most of the atom displacements. Minor actinide concentrations in the ...

... GLASS, NUCLEAR MAGNETIC RESONANCE), HIGH TEMPERATURE, TRANSITION TEMPERATURE, NUCLEAR ELECTRIC MOMENTS ...

... Descriptors : *GLASS, *THERMAL INSULATION, *THERMAL RADIATION, COMBUSTION, INHIBITION, MATERIALS, NUCLEAR EXPLOSIONS ...

... Accession Number : ADP007758. Title : Microwave Processing of Simulated Nuclear Waste Glass,. Corporate Author : FLORIDA ...

Phase separation in nuclear waste glasses has an adverse effect on glass durability. Phase separation in glasses generally takes the form of two immiscible glass phases which differ in chemical composition, density, and surface tension. Usually one phase ...

... Title : NUCLEAR TRACK REGISTRATION IN DOSIMETER GLASSES FOR NEUTRON DOSIMETRY IN MIXED RADIATION FIELDS,. ...

Spherical particles of glass containing fissile or fertile material are suspended in the ccolant of a nuclear reactor.

Aging of simulated nuclear waste glass by contact with a controlled-temperature, humid atmosphere results in the formation of a double hydration layer penetrating the glass, as well as the formation of minerals on the glass surface. The hydration process ...

A short summary is given of our studies on the major factors that affect the chemical durability of nuclear waste glasses. These factors include glass composition, solution composition, SA/V (ratio of glass surface area to the volume of solution), radiati...

The chemical durability of simulated nuclear waste glasses having different water contents was studied. Results from the product consistency test (PCT) showed that glass dissolution increased with water content in the glass. This trend was not observed du...

... Title : SILVER PHOSPHATE GLASS DOSIMETRY AND ITS USE AT THE US ARMY NUCLEAR DEFENSE LABORATORY,. ...

... Title : COBALT BOROSILICATE GLASS GAMMA DOSIMETRY AND ITS USE AT THE US ARMY NUCLEAR DEFENSE LABORATORY. ...

A thermodynamic model of glass durability is applied to natural, ancient, and nuclear waste glasses. The durabilities of over 150 different natural and man-made glasses, including actual ancient Roman and Islamic glasses (Jalame ca. 350 AD, Nishapur 10-11...

This paper presents the details of the waste glass tutorial session that was held to promote knowledge of waste glass technology and how this can be used at the Hanford Reservation. Topics discussed include: glass properties; statistical approach to glass development; processing properties of ...

... This Nd/glass laser, is not 'state of the art' rather it is ... Descriptors : *NUCLEAR FUSION, *NEODYMIUM LASERS, *GLASS LASERS, Q SWITCHING ...

High level nuclear waste from reprocessing of spent nuclear fuel has to be solidified in a stable matrix for safe long-time storage. Vitrification in borosilicate glasses is the technique accepted worldwide. A number of different glasses was developed in ...

The objective of this study was to determine the effect of microwave processing on nuclear waste glass properties. Several experiments were carried out using microwave heating techniques using borosilicate glass frit containing simulated nuclear waste mat...

The effects of atmospheric moisture and radiation damage on fracture properties of nuclear waste glasses and ceramics was investigated by indentation techniques. In nuclear waste glasses, atmospheric moisture has no measurable effect on hardness but decre...

... Title : Nuclear Radiation-Induced Dimensional Changes in Borosilicate Glass Substrates. ... in Pyrex(Registered) and Hoya SD-2(Registered) glasses. ...

A short summary is given of our studies on the major factors that affect the chemical durability of nuclear waste glasses. These factors include glass composition, solution composition, SA/V (ratio of glass surface area to the volume of solution), radiation, and colloidal formation. These investigations have ...

A short summary is given of our studies on the major factors that affect the chemical durability of nuclear waste glasses. These factors include glass composition, solution composition, SA/V (ratio of glass surface area to the volume of solution), radiation, and colloidal formation. These investigations have ...

of molybdenum from (simulant) HLW glasses. In the general model for glass corrosion in aqueous solution, networkTHE STRUCTURAL CHEMISTRY OF MOLYBDENUM IN MODEL HIGH LEVEL NUCLEAR WASTE GLASSES, INVESTIGATED of molybdenum in model UK high level nuclear waste glasses was ...

This paper briefly describes various technological concepts for the solidification/encapsulation/immobilization of radionuclides associated with liquid nuclear wastes. The concept based on borosilicate glasses is the current choice by many countries, including the United States, for solidification of high-level liquid wastes. Porous ...

... (Author). Descriptors : *Nuclear magnetic resonance, *Polymers, Glass, Transitions, Amorphous materials, Molecules, Motion, Toluenes, Liquids ...

Dissolution of nuclear waste glass occurs by corrosion mechanisms similar to those of other solids, e.g., metallurgical and mineralogic systems. Metallurgical phenomena such as active corrosion, passivation and immunity have been observed to be a function of the glass composition and the solution pH. Hydration thermodynamics was used ...

A thermodynamic model of glass durability based on hydration of structural units has been applied to natural glass, medieval window glasses, and glasses containing nuclear waste. The relative durability predicted from the calculated thermodynamics correlates directly with the experimentally ...

Molten glass characteristics of temperature, resistivity, and viscosity can be monitored reliably in the high temperature and chemically corrosive environment of nuclear waste glass melters using millimeter-wave sensor technology. Millimeter-waves are ideally suited for such meas...

The phenomenological behavior of commercial silicate glasses and nuclear borosilicate glasses in confined glass:aqueous solution systems is similar. For commercial silicate glasses the behavior has been described, ''If the neutral solution is unbuffered a...

Glass dissolution takes place through metal leaching and hydration of the glass surface accompanied by development of alternation layers of varying crystallinity. The reaction which controls the long-term glass dissolution rate appears to be surface layer...

A kinetic model for the dissolution of borosilicate glass is used to predict the dissolution rate of a nuclear waste glass. In the model, the glass dissolution rate is controlled by the rate of dissolution of an alkali-depleted amorphous surface (gel) lay...

A kinetic model for the dissolution of borosilicate glass, incorporated into the EQ3/6 geochemical modeling code, is used to predict the dissolution rate of a nuclear waste glass. The glass dissolution rate is controlled by the rate of dissolution of an a...

The main objective of the experiments was to produce in the laboratory an altered basalt glass similar to basalt glass altered in a natural environment. This objective has been accomplished with a very good correlation between the observed alteration of b...

This report discusses a methodology for increasing the efficiency and decreasing the cost of vitrifying nuclear waste by optimizing waste-glass formulation. This methodology involves collecting and generating a property-composition database (for glass pro...

Glass crystallization was investigated as part of a property-composition relationship study of Hanford waste glasses. Non-radioactive glass samples were heated in a gradient furnace over a wide range of temperatures. The liquidus temperature was measured,...

This study was undertaken to investigate the effect of elevated sulfate and molybdenum concentrations in nuclear waste glasses. A matrix of 24 glasses was developed and the glasses were tested for acceptability based on visual observations, canister cente...

... The Main topics are Crystals, Laser Glasses and Semiconductors; Magnetohydrdoynamics; Nuclear Physics; Optics and Spectroscopy; Plasma ...

... RELAXATION TIME, CRYSTAL DEFECTS, QUARTZ, GLASS, STRAIN( MECHANICS), TEMPERATURE, NUCLEAR SPINS, HYDROGEN ...

... Descriptors : *MOISTURE, *DEGRADATION, *NUCLEAR MAGNETIC RESONANCE, *FIBER REINFORCED COMPOSITES, *GLASS ...

Aging of simulated nuclear waste glass by contact with a controlled-temperature, humid atmosphere results in the formation of a double hydration layer penetrating the glass, as well as the formation of minerals on the glass surface. The hydration process can be described by Arrhenius behavior between 120 and ...

Proceedings of Symposium on Scientific Basis for Nuclear Waste Management, MRS Fall Meeting, November 30-December 4, 1998.

This contribution addresses various aspects of nuclear waste vitrification. Nuclear wastes have a variety of components and composition ranges. For each waste composition, the glass must be formulated to possess acceptable processing and product behavior ...

The hydration of an outer layer on nuclear waste glasses is known to occur during leaching, but the actual speciation of hydrogen (as water or hydroxyl groups) in these layers has not been determined. As part of the Nevada Nuclear Waste Storage Investigat...

This report discusses the development of vitrification for the waste treatment of nuclear weapons components at the Savannah River Site. Preliminary testing of surrogate nuclear weapon electronic waste shows that glass vitrification is a viable, robust treatment method.

This report discusses the development of vitrification for the waste treatment of nuclear weapons components at the Savannah River Site. Preliminary testing of surrogate nuclear weapon electronic waste shows that glass vitrification is a viable, robust treatment method.

This report reviews and summarizes studies performed to characterize the products and processes involved in the corrosion of natural glasses. Studies are also reviewed and evaluated on how well the corrosion of natural glasses in natural environments serves as an analogue for the corrosion of high-level radioactive waste glasses in an ...

This work describes immobilization of high level nuclear wastes in sintered glass, as alternative way to melting glass. Different chemical compositions of borosilicate glass with simulated waste were utilized and satisfactory results were obtained at labo...

CORROSION OF NUCLEAR WASTE GLASSES IN NON-SATURATED CONDITIONS: TIME-TEMPERATURE BEHAVIOUR Michael the corrosion of nuclear waste glasses in terms of time-temperature (t, T) parameters. A linear (non corrosion mechanisms depending on disposal conditions and exposure time. The initial stage of ...

... Summary: Development of Techniques for Measuring Elemental Profiles Near Glass Surfaces Using Nuclear Reaction Analysis and Rutherford ...

... Accession Number : ADD422266. Title : Glass Transition Temperatures of Epoxy Resins by Pulsed Nuclear Magnetic Resonance Spectroscopy,. ...

... Pagination or Media Count : 33. Abstract : The silver-activated phosphate-glass microdosimeter system employed at the US Army Nuclear Defense ...

For isolation of nuclear wastes through the vitrification process, waste slurry is mixed with borosilicate based glass and remelted at high temperature. During these processes, water can enter into the final waste glass. It is known that water in silica and silicate glasses changes various ...

Borosilicate glasses will be used in the USA and in Europe to immobilize radioactive high level liquid wastes (HLLW) for ultimate geologic disposal. Process and product quality models based on glass composition simplify the fabrication of the borosilicate glass while ensuring glass processability and quality. The ...

Borosilicate glasses will be used in the USA and in Europe to immobilize radioactive high level liquid wastes (HLLW) for ultimate geologic disposal. Process and product quality models based on glass composition simplify the fabrication of the borosilicate glass while ensuring glass processability and quality. The ...

A comprehensive investigation of natural and manmade silicate glasses, and nuclear melt glass was undertaken in order to derive an estimate of glass reactive surface area. Reactive surface area is needed to model release rates of radionuclides from nuclear melt glass in the ...

A mineral waste form has been developed for chloride waste salt generated during the pyrochemical treatment of spent nuclear fuel. The waste form consists of salt-occluded zeolite powders bound within a glass matrix. The zeolite contains the salt and immobilizes the fission products. The zeolite powders are hot pressed to form a mechanically stable, ...

It has been shown that the incorporation of lead metal into the corrosion environment reduces the leaching rate of nuclear waste glasses. The present study evaluated the effects of lead metal, oxides, alloys, glasses and soluble species on the corrosion rate of a waste glass. The inherent durability of ...

Three approaches to the development of a high density scintillation glass were investigated: They include the increase of density of glass systems containing cerium - the only systems which were known to show scintillation, the testing of a novel silicate...

The effect of gamma radiation on the durability and microstructure of a simulated nuclear waste glass from the Savannah River Site has been carefully investigated. Three large pieces of glass were irradiated with a Co-60 source to three doses up to a maxi...

Glass monoliths of the WVCM 44, WVCM 50, SRL 165, and SRL 202 compositions were reacted in steam and in hydrothermal liquid at 200(degree)C. The glass reaction resulted in the formation of leached surface layers in both environments. The reaction in steam...

Glass-bonded zeolite is being considered as a candidate ceramic waste form for storing radioactive isotopes separated from spent nuclear fuel in the electrorefining process. To determine the stability of glass-bonded zeolite under irradiation, transmissio...

Liquid high-level nuclear waste will be immobilized at the Savannah River Site (SRS) by vitrification in borosilicate glass. To fulfill this requirement, glass samples were heat treated at various times and temperatures. These results will provide guidanc...

Boron oxide plays a significant role in numerous glasses of high technological importance, such as nuclear wastes management, electronics, low density fibrous silica insulation used in space vehicles, and radiation dosimetry. Lithium borate glasses were p...

A study was made of radiation-induced dimensional changes in Pyrex(Registered) and Hoya SD-2(Registered) glasses. These glasses are used as substrates for MEMS devices employing silicon oscillating beams, and changes in substrate dimension can compromise ...

This report reviews and summarizes studies performed to characterize the products and processes involved in the corrosion of natural glasses. Studies are also reviewed and evaluated on how well the corrosion of natural glasses in natural environments serv...

The Defense Waste Processing Facility under construction at the Savannah River Plant will immobilize the radioactive waste generated by nuclear fuel processing in a borosilicate glass matrix. The ferrous-ferric ratio of the glass is a measure of its redox...

The search for a host solid for the immobilization of nuclear waste has focused on various vitreous waste forms. Recently, lead-iron-phosphate (LIP) glasses have been proposed for solidification of all types of HLLW. Investigation of this glass for vitrif...

The goal of this study was to determine the impacts of glass compositions with high aluminum concentrations on melter performance, crystallization and chemical durability for Savannah River Site (SRS) and Hanford waste streams. Glass compositions for Hanf...

The aim of this work is to understand the involved mechanisms during the decomposition of glasses by water and the consequences on the morphology of the decomposition layer, in particular in the case of a nuclear glass: the R(sub 7) T(sub 7). The chemical...

Liquid high-level nuclear waste will be immobilized at the Savannah River Site (SRS) by vitrification in borosilicate glass. Experimental glass melters, used to develop the vitrification process, have occasionally experienced problems with pluggage of the...

The conversion of high level radioactive liquid wastes into glass is now considered in every nuclear country. The glass composition must take into account the components of the solutions and be formulated in order to meet certain requirements, mainly thos...

The purpose of the Glass Furnace Project is to evaluate the use of a joule-heated glass furnace, fitted with a Mound-developed offgas system, to reduce the volume of contaminated waste typical of that from nuclear power plants. As part of the project, sev...

The purpose of the Glass Furnace Project is to evaluate the use of joule-heated glass furnace, fitted with a Mound-developed offgas system, to reduce the volume of contaminated waste typical of that from nuclear power plants. As part of the project, sever...

Procedures and techniques were evaluated to mitigate thermal stress fracture in waste glass as the glass cools after casting. The two principal causes of fracture identified in small-scale testing are internal thermal stresses arising from excessive therm...

Optical properties of fluoride glasses make them attractive materials for optical transmission and low-loss optical fibers. In order to develop optical fiber systems in nuclear media, it is essential to observe the behavior of these fluoride glasses under...

Twenty alumino-borosilicate glass compositions containing simulated fission product oxides were defined using the experimentation plan methodology. Three additional glass compositions were also tested. Significant but only qualitative correlations were es...

A mineral waste form has been developed for chloride waste salt generated during the pyrochemical treatment of spent nuclear fuel. The waste form consists of salt-occluded zeolite powders bound within a glass matrix. The zeolite contains the salt and immo...

Borosilicate glass is to be used for permanent disposal of high-level nuclear waste in a geologic repository. Mechanistic chemical models are used to predict the rate at which radionuclides will be released from the glass under repository conditions. The ...

Measurements of the nuclear relaxation rates reveal a dramatic slowing-down of the orientational fluctuations on approaching the quadrupolar glass phase in solid H sub 2 . (Atomindex citation 13:670635)

An electrochemical series of redox couples, originally developed for Savannah River Laboratory glass frit 131 (SRL-131) as a reference composition, has been extended to two other alkali borosilicate compositions that are candidate glasses for nuclear wast...

High-level liquid nuclear wastes produced at the Idaho Chemical Processing Plant (ICPP) was converted to a dry calcine powder. The feasibility of converting this calcine to a durable waste glass is being evaluated at ICPP. Candidate waste glass compositio...

Chemical durability is of primary concern when evaluating the safety of waste glass. For this reason, testing the leachability of waste glasses is a fundamental part of their development and characterization. The leachability is also very much a function ...

An Analytical Electron Microscopy study of colloidal particles formed during reaction of waste glass has been performed. The effect of waste glass test parameters on colloid formation is examined. Characterization of phases present in the leachate of thes...

A process is described for making waste glass that circumvents the problems of dissolving nuclear waste in molten glass at high temperatures. Because the reactive mixing process is independent of the inherent viscosity of the melt, any glass composition c...

High level nuclear waste is commonly incorporated into glass for disposal. Therefore the long term aqueous durability of the waste glass is important. The leaching behavior of three simulated nuclear waste glasses (AH10, AH165, and Frit 165) and a natural glass (tektite) ...

An alkoxide glass former composition has silica-containing constituents present as solid particulates of a particle size of 0.1 to 0.7 micrometers in diameter in a liquid carrier phase substantially free of dissolved silica. The glass former slurry is resistant to coagulation and may contain other glass former metal constituents. The ...

Characterization of glass corrosion requires a comprehensive evaluation of the mechanisms by which corrosion can occur. Furthermore, several such mechanisms may be operative during the lifetime of the glass. A variety of surface and solution analytical techniques have been used to achieve a better understanding of the interaction of ...

The chemical durability of simulated nuclear waste glasses having different water contents was studied. Results from the product consistency test (PCT) showed that glass dissolution increased with water content in the glass. This trend was not observed during MCC-1 testing. This difference was attributed to the ...

The SON 68 inactive (open quotes)R7T7(close quotes) composition is the French reference glass for the LWR nuclear waste glass. Vapor phase alteration was used to accelerate the reaction progress of glass corrosion and to develop the characteristic suite o...

Gamma-induced volatility of simulated DWPF high-level nuclear waste glasses is highly dependent upon the redox state of the glass. For oxidized glasses with an Fe(sup 2+)/(Fe(sup 2+) + Fe(sup 3+)) ratio

. INTRODUCTION Alkali borosilicate glasses are used by British Nuclear Fuels (BNFL) to vitrify HLW raffinates in an alkali borosilicate glass composition that is currently used for HLW vitrification in the UK of Mo in simple alkali borosilicate glasses can be at least partially reduced from Mo6+ to Mo3

In spite of their potential roles as melting rate accelerators and foam breakers, halogens are generally viewed as troublesome components for glass processing. Of five halogens, F, Cl, Br, I, and At, all but At may occur in nuclear waste. A nuclear waste ...

Ion implantation is a convenient means of simulating alpha -decay damage in nuclear waste glasses. Rutherford backscattering spectrometry and elastic recoil detection show that significant near-surface compositional changes can occur in leached Pb-ion imp...

The physical and thermal properties of three simulated nuclear waste glasses (high iron, TDS and high alumina) and their melts were measured. The low temperature properties included: thermal diffusivity, thermal expansion, Young's modulus, modulus of rupt...

Experimental determinations of the properties of lead-iron phosphate glasses pertinent to their application to the problem of permanently disposing of high-level nuclear wastes have been carried out. These investigations included studies of the compositio...

Dissolution of nuclear waste glass occurs by corrosion mechanisms similar to those of other solids, e.g., metallurgical and mineralogic systems. Metallurgical phenomena such as active corrosion, passivation and immunity have been observed to be a function...

The safe disposal of high-level radioactive wastes from nuclear reactors is a major problem because of the danger of life which may arise if these substances were released into the environment. Disposal of nuclear wastes in glass requires assurance that t...

Multicomponent systems tests of the durability of fuel recycle waste glass are an important tool to assess the long-term performance of a nuclear waste isolation system. A fractional factorial design was chosen for these test, with three parameters: the c...

The influence of the surface finish on nuclear glass dissolution was investigated. Seven different surface finishes were tested: a specimen as cut four specimens polished to grades 220, 600, 4000 and 1 (mu)m, a flame-polished specimen and a thermal ruptur...

A study of the effect of chromium on the properties of selected glasses was performed in the frame of a Contract between Battelle, Pacific Northwest Laboratories and Nuclear Research Institute, ReZ. In the period from July 1994 to June 1995 two borosilica...

Time-temperature-transformation (TTT) curves have been determined for simulated nuclear waste glasses bounding the compositional range in the Defense Waste Processing Facility (DWPF). Formulations include all of the minor chemical elements such as rutheni...

-implanted soda-lime silicate glass (500 keV, annealed at 512�C) and borosilicate glass (400 keV, annealed at 400 keV Er implanted alkali-borosilicate glass. This glass was annealed at 4Oo"C, the temperature by Eq. (1). Indeed, borosilicate glass contains OH quenching impurities, as ...

Currently, the primary interest in glass for nuclearpowered aircraft applications is in opticai systems, electron tabes, and dosimetry. Coloration is undesirable in opticai systems and may render them useless. Radiation damage to glass has resulted in mechanical failure of electron tubes. The dosimeter application, on the other hand, depends on ...

R7T7 glass alteration was investigated in the presence of various moist clays. In contact with smectite 4a, selected in France as a potential engineered barrier material, the glass was significantly corroded: after 6 months the glass corrosion rate was pr...

The interdiffusion mechanism governing the leaching (or hydration) of glasses is studied using the /sup 19/F resonant nuclear reaction. By measuring the number of hydrogen ions in the surface layers of leached glasses, we have identified that a hydronium-sodium ion exchange process is in operation in leached commercial ...

Corrosion of alkali�borosilicate waste glass K-26 in non-saturated conditions Michael I. Ojovan a. The main parameters, which control the corrosion of waste glass K-26 in the near-surface repository-activated processes including those causing corrosion of waste glass. Corrosion of nuclear waste ...

... topics covered are Crystal, Laser Glasses and Semiconductors; Fluid Dynamics; High Temperature Physics; Lasers; Nuclear Physics; Optics and ...

... Crystals, Laser Glasses and Semiconductors, Gas Dynamics, Fluid Dynamics, High temperature Physics, Lasers, Nuclear Physics, Optics and ...

and Nuclear Contributions to the Nonlinear Index of Beryllium Fluoride Glass," C. Cline, D. Heiman, R

temperature (Tg) than those of the current borosilicate nuclear glasses. As the actinides and lanthanides-Rich Glasses for Nuclear Waste Immobilization I. Bardez1,2,* , D. Caurant2 , J.L. Dussossoy1 , P. Loiseau2 , C Email: isabelle-bardez@enscp.jussieu.fr Abstract � New nuclear ...

The Defense Waste Processing Facility will incorporate high-level liquid waste into borosilicate glass for stabilization and permanent disposal in a geologic repository. The viscosity of the melt determines the rate of melting of the raw feed, the rate of gas bubble release due to foaming and fining, the rate of homogenization, and thus, the quality of the ...

to nuclear radiation become radioactive and emit gamma rays. Operators peer through thick glass windows and use claw-like robotic manipulator ...

... Abstract : With the imminent startup, in the United States, of facilities for vitrification of high-level nuclear waste, a document has been prepared that ...

This patent describes lead-iron phosphate glasses containing a high level of Fe/sub 2/O/sub 3/ for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste, a highly corrosion resistant, homogeneous, easily ...

The main objective of the experiments was to produce in the laboratory an altered basalt glass similar to basalt glass altered in a natural environment. This objective has been accomplished with a very good correlation between the observed alteration of basalt glass in a natural environment with that in the laboratory. The formation of ...

Disclosed are lead-iron phosphate glasses containing a high level of Fe/sub 2/O/sub 3/ for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste

Disclosed are lead-iron phosphate glasses containing a high level of Fe sub 2 O sub 3 for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste, a ...

Vitrification of nuclear waste in a glass is currently the preferred process for waste disposal. DOE currently approves only borosilicate (BS) type glasses for such purposes. However, many nuclear wastes, presently awaiting disposal, have complex and dive...

Borosilicate glass is the only material currently approved and being used to vitrify high level nuclear waste. Unfortunately, many high level nuclear waste feeds in the U.S. contain components which are chemically incompatible with borosilicate glasses. Current plans call for vit...

A thermodynamic model of glass durability is applied to natural, ancient, and nuclear waste glasses. The durabilities of over 150 different natural and man-made glasses, including actual ancient Roman and Islamic glasses (Jalame ca. 350 AD, Nishapur 10-11th century AD and Gorgon 9-11th century ...

Most long-lived radionuclides associated with an underground nuclear test are initially incorporated into melt glass and become part of the hydrologic source term (HST) only upon their release via glass dissolution (Pawloski et al., 2001). As the melt glass dissolves, secondary minerals precipitate. The types of ...

The lead-iron-phosphate nuclear waste glass developed at Oak Ridge National Laboratory (ORNL) was evaluated for its potential as an improvement over the current reference waste form, borosilicate glass. Vitreous lead-iron-phosphate glass appears to have substantially better chemical durability than borosilicate ...

Development of a host solid for the immobilization of nuclear waste has focused on various vitreous wasteforms. The systems approach requires that parameters affecting product performance and processing be considered simultaneously. Application of the systems approach indicates that borosilicate glasses are, overall, the most suitable ...

Empirical data from natural occurrences of basalt glass are interpreted by a model which has been developed to describe the reaction progress of the corrosion of nuclear waste form borosilicate glass. A description of the basalt glass/water reaction model is included. Implications are that there are similarities ...

There has been interest in the comparison of the leach behavior between fully radioactive and simulated nuclear waste glasses, to assess the differences in reaction mechanism, type, and sequence of secondary phases, and the relative durability among the two types of glasses. The results from these comparisons will provide confidence in ...

There has been interest in the comparison of the leach behavior between fully radioactive and simulated nuclear waste glasses, to assess the differences in reaction mechanism, type, and sequence of secondary phases, and the relative durability among the two types of glasses. The results from these comparisons will provide confidence in ...

In glass processing situations involving glass crystallization, various crystalline forms nucleate, grow, and dissolve, typically in a nonuniform temperature field of molten glass subjected to convection. Nuclear waste glasses are remarkable examples of multicomponent vitrified mixtures ...

The behavior of radioactive sludge-based and simulated nuclear waste glasses has been compared by long-term testing of radioactive and simulated compositions of Savannah River Laboratory 165, 131, and 200 glasses. Static tests at glass surface area-to-solution volume (SA/V) ratios of 340 and 2000 m[sup [minus]1] up ...

The Nuclear Regulatory Commission comments on the Waste Acceptance Preliminary Specification 1.1.2 (Chemical Composition During Production) questioned the exclusion of oxygen from analysis of the chemical composition of DWPF glass. They reasoned that the oxygen content is a measure of glass redox and thus could be important in ...

From asbestos abatement to lead paint removal to nuclear waste stabilization and even to heavy metal removal using microorganisms, glass has great potential as a solution to many environmental problems. The ability to accommodate an array of chemical elements within the glass structure has facilitated the use of ...

Information presented at a Meeting on Fuel Bearing Glass is summarized. Topics covered include investigations of radioactive fuel materials in glasses, glass fibers containing fissionable and fertile materials, fuel bearing fiberglas in aluminum-base fuel elements, plutoniumbearing glasses, compositional ...

Vitrification of nuclear waste in a glass is currently the preferred process for waste disposal. DOE currently approves only borosilicate (BS) type glasses for such purposes. However, many nuclear wastes, presently awaiting disposal, have complex and diverse chemical compositions, and often contain components that ...

Certain high level wastes (HLW) in the U.S. contain components such as phosphates, heavy metals, and halides which make them poorly suited for disposal in borosilicate glasses. Iron phosphate glasses appear to be a technically feasible alternative to borosilicate glasses for vitrifying these HLWs. The iron phosphate ...

The safe disposal of high-level radioactive wastes from nuclear reactors is a major problem because of the danger of life which may arise if these substances were released into the environment. Disposal of nuclear wastes in glass requires assurance that the glass will survive for a time on the order of 10{sup 6} ...

The authors analyzed the corroded surfaces of reference glasses developed for the Defense Waste Processing Facility (DWPF) to characterize their corrosion behavior. The corrosion mechanism of nuclear waste glasses must be known in order to provide source terms describing radionuclide release for performance assessment calculations. ...

The durability of natural glasses on geological time scales and ancient glasses for thousands of years is well documented. The necessity to predict the durability of high level nuclear waste (HLW) glasses on extended time scales has led to various thermodynamic and kinetic approaches. Advances in the measurement of ...

The objective of this project is to develop a fundamental understanding of radiation effects in glasses and ceramics, as well as the influence of solid-state radiation effects on aqueous dissolution kinetics, which may impact the performance of nuclear waste forms and stabilized nuclear materials.

Production of nuclear materials for defense applications has resulted in the accumulation of vast amounts of nuclear waste. This contaminated waste is in a variety of forms that require subsequent reprocessing to isolate and encapsulate the nuclear (e.g.,...

Tests are described for determining the impact resistance (Section A) and static tensile strength (Section B) of glasses containing simulated or actual nuclear wastes. This report describes the development and use of these tests to rank different glasses, to assess effects of devitrification, and to examine the effect of impact energy ...

A relatively simple model, the associate species model, is being applied to nuclear waste glass compositions in order to accurately predict behavior and thermodynamic activities in the material. In the model, the glass is treated as a supercooled liquid, with the liquid species ...

PNL 76-68, a prototype nuclear waste storage glass, was reacted under hydrothermal conditions at 100, 200, and 300 C with NBT-6a (Ca-Mg-K-Na-Cl) brine. Reaction products were identified, the state of the residual glass determined, and the concentrations o...

Glass is a suitable material for containers for radioactive waste storage but under certain conditions it might be damaged. In-situ radiation damage to simulated nuclear waste glasses was induced and observed using a high voltage electron microscope. Radiation damage was observed as the formation of oxygen bubbles in the matrix often ...

Research efforts to evaluate the process of radiation damage in nuclear waste materials has centered about the description of radiation damage in borosilicate glasses with metal oxide additions and is progressing to the evaluation of similar processes in binary silicate glasses in an attempt to isolate the role of metal cations and the ...

The unusual properties and beneficial characteristics of iron phosphate glasses, as viewed from the standpoint of alternative glasses for vitrifying nuclear and hazardous wastes (which contain components that make them poorly suited for vitrification in b...

This contributes to the study of the nuclear glasses composition influence on their liability to deterioration. The methodology of the experimental research used has lead to define between the thirty oxides which form the reference glass light water, six ...

R7T7 nuclear waste glass dissolution in highly dilute aqueous media under static conditions at 90(sup 0)C occurs according to two different mechanisms depending on the solution acidity. In acid media (pH 4.8 and 5.5), preferential extraction of glass netw...

This work deals with the general problem of alteration of the reference nuclear glass R7T7. Attention is paid particularly to the altered layer formed at the glass surface during alteration process. In opposition to previous works, related essentially to ...

Ninety simplified nuclear waste glass compositions within an 11-component oxide composition matrix were tested for crystallinity, viscosity, volatility, and chemical durability. Empirical models of property response as a function of glass composition were developed using statistical experimental design and modeling techniques. A new ...

The initial goal of this project was to investigate the solubility of radionuclides in glass and other potential waste forms for the purpose of increasing the waste loading in glass and ceramic waste forms. About one year into the project, the project decided to focus on two potential waste forms - glass at PNNL and itianate ceramics ...

Material for the burnable poison of Qinshan Nuclear Power Plant core is GG-17 borosilicate glass. The chemical composition and physico-chemical properties of GG-17 is very close to Pyrex-7740 glass used by Westinghouse. It is expected from the results of ...

A thermochemical representation of the Na-Al-Si-B-O system relevant for nuclear waste glass has been developed based on the associate species approach for the glass solution phase. Thermochemical data were assessed and associate species data determined for binary and ternary sub...

GLASS is the matrix of choice of every major country involved with long-term management of high-level radioactive waste (HLW). There are many reasons why glass is preferred. Among the most important considerations is the ability of glass structures to accommodate and immobilize the many different types of constituents present in HLW, ...

High-level nuclear waste is being vitrified, i.e., converted to a durable glass that can be stored in a safe repository for hundreds of thousands of years. Waste vitrification is accomplished in reactors called melters to which the waste is charged together with glass-forming additives. The mixture is electrically heated to a ...

In glass-bonded sodalite, which is the ceramic waste form (CWF) to immobilize radioactive electrorefiner salt from spent metallic reactor fuel, uranium and plutonium are found as 20-50 nm (U,Pu)O2 particles encapsulated in glass near glass-sodalite phase ...

The valence state of neptunium ions in sodium silicate glasses prepared under reducing and oxidizing conditions has been investigated by the x-ray photoelectron, Moessbauer and optical absorption spectroscopic techniques. Results indicate that the Np ions are tetravalent in glasses prepared under reducing conditions and pentavalent in ...

Corrosion products resulting from the reaction of simulated high-level radioactive waste glasses with various solutions have been identified. At 200degC, in saturated NaCl, a degree of reaction of 10 g C31-3 glass or 2.6 g SON 68 glass per liter of soluti...

are also reported. INTRODUCTION Borosilicate glasses used for the vitrification of HLW have good long term) that are high in Mo are particularly likely to cause devitrification in borosilicate glasses due to the low a sodium borosilicate base glass composition specified by BNFL and containing a simulated HLW composition

An inactive borosilicate glass made of about 30 oxides is studied. The composition was developed by the CEA for encapsulation of calcinated fission product solutions from reprocessing. Hydration energy of glass is first calculated for 8 glasses and result...

The results of a series of hydration experiments on natural glasses (Hawaiian basalt, obsidian) and the nuclear waste glass WV-44 done to examine laboratory methods of accelerating reaction processes are summarized. The glasses were reacted in hydrothermal solution and in saturated vapor water. It was found that ...

The lead-iron-phosphate nuclear waste glass developed at Oak Ridge National Laboratory (ORNL) was evaluated for its potential as an improvement over the current reference waste form, borosilicate glass. Vitreous lead-iron-phosphate glass appears to have s...

Because of their unusually good chemical durability, iron phosphate glasses are a natural candidate for a nuclear waste disposal glass. We have studied the effects of UO(sub 2) high-level waste on the structure of iron phosphate glasses with both neutron ...

The behaviour of borosilicate glasses upon aqueous corrosion is controlled for long periods of time (>10,000 years) by processes which are not directly accessible by means of laboratory experiments. The analogical approach consists here to compare leachin...

An Analytical Electron Microscopy study of colloidal particles formed during reaction of wste glass has been performed. The effect of waste glass test parameters on colloid formation is examined. Characterization of phases present in the leachate of these tests has shown that layers spalled from the glass and precipitated phases are ...

An Analytical Electron Microscopy study of colloidal particles formed during reaction of wste glass has been performed. The effect of waste glass test parameters on colloid formation is examined. Characterization of phases present in the leachate of these tests has shown that layers spalled from the glass and precipitated phases are ...

Objectives of this project are to: (1) investigate the glass composition and processing conditions that yield optimum properties for iron phosphate glasses for vitrifying radioactive waste, (2) determine the atomic structure of iron phosphate glasses and ...

A process is described for making waste glass that circumvents the problems of dissolving nuclear waste in molten glass at high temperatures. Because the reactive mixing process is independent of the inherent viscosity of the melt, any glass composition can be prepared with equal facility. Separation of the mixing ...

The effects of groundwater chemistry on glass durability were examined using the hydration thermodynamic model. The relative durabilities of SiO{sub 2}, obsidians, basalts, nuclear waste glasses, medieval window glasses, and a frit glass were determined in tuffaceous groundwater, basaltic ...

A comparison of glass reactivity between radioactive sludge based and simulated nuclear waste glasses has been made through long-term testing of both glass types for SRL 165, SRL 131, and SRL 200 frit compositions. The data demonstrate that for time periods through 280 days, differences in elemental release to ...

Leaching of waste glass in lead and aluminum containers is much less extreme than in relatively inert Teflon containers. Lead and aluminum are already included in several waste-package designs. The chemical durability imparted to a waste glass by sorption of lead and aluminum corrosion products onto the glass surfaces, as reported in ...

We present a short review of current theories of glass weathering, including glass dissolution, and hydrolysis of nuclear waste glasses, and leaching of historical glasses from an XAFS perspective. The results of various laboratory leaching experiments at different timescales (30 days to 12 ...

We present a short review of current theories of glass weathering, including glass dissolution, and hydrolysis of nuclear waste glasses, and leaching of historical glasses from an XAFS perspective. The results of various laboratory leaching experiments at different timescales (30 days to 12 ...

Liquid high-level nuclear waste will be immobilized at the Savannah River Site (SRS) by vitrification in borosilicate glass. The glass will be processed in the Defense Waste Processing Facility (DWPF) and poured into stainless steel canisters for eventual geologic disposal. Six simulated glass compositions will be ...

Liquid high-level nuclear waste will be immobilized at the Savannah River Site (SRS) by vitrification in borosilicate glass. The glass will be processed in the Defense Waste Processing Facility (DWPF) and poured into stainless steel canisters for eventual geologic disposal. Six simulated glass compositions will be ...

This review summarizes the results of the joint Japanese (Central Research Institute of Electric Power Industry, CRIEPI, Tokyo), Swiss (National Cooperative for the Storage of Radioactive Waste, NAGRA, Baden), Swedish (Swedish Nuclear Fuel and Waste Management Company, SKB, Stockholm) international JSS' project on the determination of the chemical durability of the ...

From 1975 to 1996 the French detonated 140 underground nuclear explosions beneath the atolls of Mururoa and Fangataufa in the South Pacific; from 1965 to 1971 the United States detonated three high yield nuclear tests beneath Amchitka Island in the Aleutian chain. Approximately 800 metric tons of basalt is melted per kiloton of nuclear ...

Millimeter-wave technologies can provide novel and reliable online monitoring capability for many important parameters inside nuclear waste glass melters, including temperature, emissivity, density, and viscosity. The physical and analytical basis for millimeter-wave monitoring o...

Small volumes with lead brick and lead glass shielding are used, and in nuclear technology we call them ''hot cells''. Furthermore for separating the exposure rooms from the operator rooms lead glassed windows of heavy concrete walls can be used. Unfortun...

Liquid high-level nuclear waste will be immobilized at the Savannah River Site (SRS) by vitrification in borosilicate glass in the Defense Waste Processing Facility (DWPF). A similar vitrification facility exists at the West Valley Nuclear Fuel Services. In both of these facilities, control of the oxidation/reduction (redox) ...

The temperature dependence of glass durability, particularly that of nuclear waste glasses, is assessed by reviewing past studies. The reaction mechanism for glass dissolution in water is complex and involves multiple simultaneous reaction proceeded, including molecular water diffusion, ion exchange, surface ...

Recent reviews which have dealt with critical issues regarding the suitability of glasses for nuclear waste disposal have identified liquid-liquid immiscibility and crystallization processes as having the potential to alter significantly storage behavior, especially chemical corr...

This paper is part of a larger investigation of the role of amines in the adhesion of polybutadience to glass substrates. It describes near infrared, infrared and nuclear magnetic resonance spectroscopy studies of the interaction of amines with silanol gr...

The second phase of the composition variation study (CVS) for the development of glass compositions to immobilize Idaho Nuclear Technology and Engineering Center (INTEC) high level wastes (HLW) is complete. This phase of the CVS addressed waste compositio...

Dissolution of nuclear waste glass occurs by corrosion mechanisms similar to those of metallurgical and mineralogic systems albeit on different time scales. The effects of imposed pH and oxidation potential (Eh) conditions existing in natural environments...

Chemical shift measurements on 205Tl in thallium borate glasses at temperatures up to and above the softening temperature (300C) indicate that the interactions of Tl(I) with oxygen atoms in the borate network are predominantly ionic. There is relatively l...

A glass-bonded ceramic waste form is being developed to immobilize high-level chloride waste salts generated during the conditioning of spent sodium-bonded nuclear fuel for disposal. The waste salt is loaded into zeolite cavities, mixed with a borosilicat...

Nuclear magnetic resonance techniques have been used to study atomic arrangements and chemical bonds in glasses. The principal results are as follows: (1) NMR distinguishes between BO3 and BO4, configurations; quantitative measures of each configuration i...

Samples of SRP glass containing either simulated or actual radioactive waste were leached at 90 degrees C under conditions simulating a saturated tuff repository environment. The leach vessels were fabricated of tuff and actual tuff groundwater was used. ...

Because electric glass melters for vitrification of nuclear wastes will be operated remotely, the expected lifetime of each component must be maximized. Four candidate electrode materials (two types of tin oxide, molybdenum, and Inconel 690) have been tes...

The report summarizes the entire development program conducted by Tem-Pres Research/Carborundum which experimentally demonstrated that hydrogen impregnation will significantly reduce darkening of solar cell glass covers under solar, nuclear, and van Allen...

The effect of gamma radiolysis of a deaerated, saturated, NaCl-rich brine on leaching of a simulated nuclear waste glass was evaluated at 50 and 90 exp 0 C and included interactive tests with ductile iron. Leach rate enhancements due to radiolysis were gr...

The long-term behavior of nuclear waste glass in a geologic repository may require a technical consideration of the role of colloids in the release and transport of radionuclides. The neglect of colloidal properties in assessing the near- and far-field mi...

Seventy-three papers are included, arranged under the following section headings: national programs for the disposal of radioactive wastes, waste from stability and characterization, glass processing, ceramic processing, ceramic and glass processing, leac...

The bonding configurations for simple phosphate glasses are quantitatively described by both the relative concentrations of different polyhedral phosphate sites (i.e., the Q(sup n) description) determined by (sup 31)p magic angle spinning nuclear magnetic...

Nuclear waste forms presently used for the disposal of high level wastes and other potential waste forms under development were studied. The following waste forms were considered: Borosilicate glass, high silica glass, glassceramics, supercalcine ceramics...

This initial work is aimed at developing a basic understanding of the phase equilibria and solid solution behavior of the constituents of waste glass. Current, experimentally determined values are less than desirable since they depend on measurement of the leach rate under non-r...

To predict the long-term effects of groundwater contact on the durability of nuclear waste glass in a geologic repository the nature of the glass dissolution process must be understood. Hydration thermodynamics has been used to quantify the role of glass composition and the effect of solution pH. The ...

The lead-iron-phosphate (Pb-Fe-P) glass developed at Oak Ridge National Laboratory was evaluated for its potential as an improvement over the current reference nuclear waste form, borosilicate (B-Si) glass. The evaluation was conducted as part of the Second Generation HLW Technology Subtask of the Nuclear Waste ...

High-level liquid nuclear wastes produced at the Idaho Chemical Processing Plant (ICPP) was converted to a dry calcine powder. The feasibility of converting this calcine to a durable waste glass is being evaluated at ICPP. Candidate waste glass compositions were developed and plans were made to construct and operate a laboratory ...

Vitrification of nuclear wastes is attractive because of its flexibility, the large number of elements which can be incorporated in the glass, its high corrosion durability and the reduced volume of the resulting waste form. Vitrification is a mature technology and has been used for high level nuclear waste (HLW) immobilisation for ...