Download or read book Nuclear Waste Glasses Suitability Surface Studies and Stability written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Every major country involved with long-term management of high-level radioactive waste (HLW) has either selected or is considering glass as the matrix of choice for immobilizing and ultimately, disposing of the potentially hazardous, high-level radioactive material. There are many reasons why glass is preferred. Among the most important considerations are the ability of glass structures to accommodate and immobilize the many different types of radionuclides present in HLW, and to produce a product that not only has excellent technical properties, but also possesses good processing features. Good processability allows the glass to be fabricated with relative ease even under difficult remote-handling conditions necessary for vitrification of highly radioactive material. The single most important property of the waste glass produced is its ability to retain hazardous species within the glass structure and this is reflected by its excellent chemical durability and corrosion resistance to a wide range of environmental conditions.
Download or read book Surface Studies of Nuclear Waste Glasses written by and published by . This book was released on 1999 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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, and to produce a product that not only has excellent technical properties, but also processes good processing features.
Download or read book Surface active Processes in Materials written by Larry L. Hench and published by . This book was released on 2000 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Proceedings of the Larry Hench Symposium on Surface-Active Processes in Materials, held at the 23rd Annual Cocoa Beach Conference, Cocoa Beach, Florida, January 25-29, 1999."--T.p. verso.
Download or read book The Chemistry of the Actinide and Transactinide Elements 3rd ed Volumes 1 5 written by L.R. Morss and published by Springer Science & Business Media. This book was released on 2007-12-31 with total page 4059 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Chemistry of the Actinide and Transactinide Elements is a contemporary and definitive compilation of chemical properties of all of the actinide elements, especially of the technologically important elements uranium and plutonium, as well as the transactinide elements. In addition to the comprehensive treatment of the chemical properties of each element, ion, and compound from atomic number 89 (actinium) through to 109 (meitnerium), this multi-volume work has specialized and definitive chapters on electronic theory, optical and laser fluorescence spectroscopy, X-ray absorption spectroscopy, organoactinide chemistry, thermodynamics, magnetic properties, the metals, coordination chemistry, separations, and trace analysis. Several chapters deal with environmental science, safe handling, and biological interactions of the actinide elements. The Editors invited teams of authors, who are active practitioners and recognized experts in their specialty, to write each chapter and have endeavoured to provide a balanced and insightful treatment of these fascinating elements at the frontier of the periodic table. Because the field has expanded with new spectroscopic techniques and environmental focus, the work encompasses five volumes, each of which groups chapters on related topics. All chapters represent the current state of research in the chemistry of these elements and related fields.
Download or read book The Chemistry of the Actinide and Transactinide Elements Set Vol 1 6 written by L.R. Morss and published by Springer Science & Business Media. This book was released on 2010-10-21 with total page 4511 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fourth edition of "The Chemistry of the Actinide and Transactinide Elements" comprises all chapters in volumes 1 through 5 of the third edition (published in 2006) plus a new volume 6. To remain consistent with the plan of the first edition, “ ... to provide a comprehensive and uniform treatment of the chemistry of the actinide [and transactinide] elements for both the nuclear technologist and the inorganic and physical chemist,” and to be consistent with the maturity of the field, the fourth edition is organized in three parts. The first group of chapters follows the format of the first and second editions with chapters on individual elements or groups of elements that describe and interpret their chemical properties. A chapter on the chemical properties of the transactinide elements follows. The second group, chapters 15-26, summarizes and correlates physical and chemical properties that are in general unique to the actinide elements, because most of these elements contain partially-filled shells of 5f electrons whether present as isolated atoms or ions, as metals, as compounds, or as ions in solution. The third group, chapters 27-39, focuses on specialized topics that encompass contemporary fields related to actinides in the environment, in the human body, and in storage or wastes. Two appendices at the end of volume 5 tabulate important nuclear properties of all actinide and transactinide isotopes. Volume 6 (Chapters 32 through 39) consists of new chapters that focus on actinide species in the environment, actinide waste forms, nuclear fuels, analytical chemistry of plutonium, actinide chalcogenide and hydrothermal synthesis of actinide compounds. The subject and author indices and list of contributors encompass all six volumes.
Download or read book Glass as a Waste Form and Vitrification Technology written by National Research Council and published by National Academies Press. This book was released on 1997-03-02 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Environmental Degradation of Advanced and Traditional Engineering Materials written by Lloyd H. Hihara and published by CRC Press. This book was released on 2013-10-23 with total page 722 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the main, ongoing challenges for any engineering enterprise is that systems are built of materials subject to environmental degradation. Whether working with an airframe, integrated circuit, bridge, prosthetic device, or implantable drug-delivery system, understanding the chemical stability of materials remains a key element in determining their useful life. Environmental Degradation of Advanced and Traditional Engineering Materials is a monumental work for the field, providing comprehensive coverage of the environmental impacts on the full breadth of materials used for engineering infrastructure, buildings, machines, and components. The book discusses fundamental degradation processes and presents examples of degradation under various environmental conditions. Each chapter presents the basic properties of the class of material, followed by detailed characteristics of degradation, guidelines on how to protect against corrosion, and a description of testing procedures. A complete, self-contained industrial reference guide, this valuable resource is designed for students and professionals interested in the development of deterioration-resistant technological systems constructed with metallurgical, polymeric, ceramic, and natural materials.
Download or read book Factors Influencing Chemical Durability of Nuclear Waste Glasses written by and published by . This book was released on 1993 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 enabled us to gain a better understanding of the chemical durability of nuclear waste glasses and to accumulate.a data base for modeling the long-term durability of waste glass, which will be used in the risk assessment of nuclear waste disposal. This knowledge gained also enhances our ability to formulate optimal waste glass compositions.
Download or read book Oversight Nuclear waste management written by United States. Congress. House. Committee on Science and Technology. Subcommittee on Fossil and Nuclear Energy Research, Development, and Demonstration and published by . This book was released on 1978 with total page 1178 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nuclear Waste Management written by United States. Congress. House. Committee on Science and Technology. Subcommittee on Fossil and Nuclear Energy Research, Development, and Demonstration and published by . This book was released on 1978 with total page 1164 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Exploration and Modeling of Structural Changes in Waste Glass Under Corrosion written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Vitrification is currently the world-wide treatment of choice for the disposition of high-level nuclear wastes. In glasses, radionuclides are atomistically bonded into the solid, resulting in a highly durable product, with borosilicate glasses exhibiting particularly excellent durability in water. Considering that waste glass is designed to retain the radionuclides within the waste form for long periods, it is important to understand the long-term stability of these materials when they react in the environment, especially in the presence of water. Based on a number of previous studies, there is general consensus regarding the mechanisms controlling the initial rate of nuclear waste glass dissolution. Agreement regarding the cause of the observed decrease in dissolution rate at extended times, however, has been elusive. Two general models have been proposed to explain this behavior, and it has been concluded that both concepts are valid and must be taken into account when considering the decrease in dissolution rate. Furthermore, other processes such as water diffusion, ion exchange, and precipitation of mineral phases onto the glass surface may occur in parallel with dissolution of the glass and can influence long-term performance. Our proposed research will address these issues through a combination of aqueous-phase dissolution/reaction experiments and probing of the resulting surface layers with state-of-the-art analytical methods. These methods include solid-state nuclear magnetic resonance (SSNMR) and time-of-flight secondary ion mass spectrometry (TOF-SIMS). The resulting datasets will then be coupled with computational chemistry and reaction-rate modeling to address the most persistent uncertainties in the understanding of glass corrosion, which indeed have limited the performance of the best corrosion models to date. With an improved understanding of corrosion mechanisms, models can be developed and improved that, while still conservative, take advantage of the inherent durability of the waste form to enable secure repositories to be engineered with a much higher density of waste disposition. We propose the synthesis, corrosion, and characterization of two sets of glass samples-- containing approximately 8 single-component oxides each--as models for corrosion studies of more complicated glass systems (which can contain in excess of 25 single-component ingredients). Powdered samples and millimeter- sized coupons of these simpler glasses will be corroded in solutions that begin at circumneutral pH, but are known to increase in alkalinity as corrosion proceeds and saturation in silica species is approached. Through carefully selected isotopic substitutions with nuclides that are readily detected with SSNMR and TOF-SIMS methods, we will be able to follow the diffusion of atoms into and out of the reacted surface layers of these glasses and provide new data for testing with existing reaction models. The models can then be further extended or updated to take our new data into account, allowing the existing long-term glass corrosion models to more accurately reflect the extraordinary durability of these systems. With improved models, a significant opportunity exists to better utilize the storage volume of any geologic repository.
Download or read book Systems Approach to Nuclear Waste Glass Development written by and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 glasses for the immobilization of nuclear waste. Phosphate glasses are highly durable; but the glass melts are highly corrosive and the glasses have poor thermal stability and low solubility for many waste components. High-silica glasses have good chemical durability, thermal stability, and mechanical stability, but the associated high melting temperatures increase volatilization of hazardous species in the waste. Borosilicate glasses are chemically durable and are stable both thermally and mechanically. The borosilicate melts are generally less corrosive than commercial glasses, and the melt temperature miimizes excessive volatility of hazardous species. Optimization of borosilicate waste glass formulations has led to their acceptance as the reference nuclear wasteform in the United States, United Kingdom, Belgium, Germany, France, Sweden, Switzerland, and Japan.
Download or read book Scientific Basis for Nuclear Waste Management written by Clyde J. Northrup and published by Springer. This book was released on 2013-12-19 with total page 932 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Symposium on the Scientific Basis for Nuclear Waste Manage ment was held in the fall of 1979 in Boston, Massachusetts and was one of a number of symposia included in the Annual Meeting of the Materials Research Society. The thrust of this annual Symposium is unique in the area of waste management. Recognizing that this is an area of great complexity which requires contributions from scien tists with many different backgrounds some of which are not normally associated with nuclear energy, the Materials Research Society pro vides a forum for discussions of a wide range of materials behavior and transport phenomena. As can be seen from the list of references in each paper, the authors draw heavily on contributions associated with professional societies in addition to the Materials Research Society, and this annual meeting encourages the cross-fertilization between disciplines that are essential to an adequate treatment of the problems associated with nuclear waste management. The proceed ings of the first Symposium that was held in 1978 was designated as Volume 1 in this series. The third Symposium is scheduled for 1980. The scope of the 1979 Symposium was guided by the Steering Committee: R. L. Schwoebel, Sandia Laboratories, USA (Chairman) W. Carbiener, Battelle Memorial Institute, Columbus, USA D. Ferguson, Oak Ridge National Laboratory, USA W. Heimerl, DWK, Mol, Belgium W. Lutze, Hahn Meitner Institut, Berlin, W. Germany J. D. Mather, Institute of Geological Sciences, Harwell, UK G. Oertel, Department of Energy, USA R.
Download or read book Structure and Durability of UK Simulated High Level Nuclear Waste Glasses written by Nathan Cassingham and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The understanding of dissolution of the British nuclear waste glass, as compared to other nuclear waste glasses, is limited. The few studies that have been performed were generally done in static leach tests with the exception of the single pass flow through test performed by Abratis during his PhD, producing a number of papers (Abraitis, P.K., Univ. Manchester, 1999; Abraitis, P.K. et. al., Applied Geochemistry 15 (2000) 1399; Abraitis, P.K. et. al., Mat. Res. Soc. Sym. Pro. 556 (1999) 401). In order to gain further insight to the British nuclear waste glasses X-ray absorption spectroscopy was used along with dissolution studies of British simulated nuclear waste glasses to determine the role of Zn and to ascertain the mechanisms of corrosion. Both baseline glasses along with a Blend simulated nuclear waste glass were studied to give better comparisons with previous results by other authors. The Blend waste glass is composed of a mixture of Magnox reactor waste and thorium oxide reprocessing (ThORP) waste at a wt% of 25wt% Magnox waste and 75 wt% ThORP. Zn K edge X-ray absorption spectroscopy was applied to determine the Zn coordination environment in model inactive UK high level waste (HLW) glasses. Quantitative analysis of the X-ray absorption fine structure (EXAFS) data provided conclusive evidence for the presence of ZnO4 species participating in network formation, linking, on average, to 2 ± 1 SiO4 units via bridging oxygen atoms. Excellent quantitative agreement was observed between the Zn-O contact distance and coordination number determined from EXAFS and previous Molecular Dynamics simulations of glasses with the same nominal composition. Analysis also provided evidence in support of the network forming role of Zn as predicted from Molecular Dynamics simulation, but it was not possible to confirm the predicted clustering of Zn species at high Zn concentration in simple soda lime silica glasses. The single pass flow through (SPFT) work in this study has shown that the steady state dissolution of a base glass with 25 wt% waste loading (MW+25wt%) and a base glass with 30 wt% waste loading (MW+30wt%) of Blend simulated nuclear waste glasses is similar to that of previous studies. The SPFT flow per surface area (Q/S) results are consistent with previous studies. The dissolution rate dependency on temperature and pH of was also consistent with similar glasses. The NRi with respect to B, Si, Na and Al, of the glasses in this study increased with an increase in solution pH. The average activation energy with respect to Si was consistent for a surface controlled reaction with these glasses as was shown in previous studies on MW+Magnox, a similar glass. One of the current designs for a geological repository of HLW is a co-located repository with intermediate level waste (ILW). At long times, there is the possibility of hyper alkaline solution from the ILW repository interacting with the vitrified HLW glass wasteforms. Dissolution studies were performed to understand the mechanisms by which the UK HLW glasses will corrode under hyper alkaline solutions. The addition of an alkali buffer to high purity H2O resulted in a decrease of the dissolution rate for the MW Blend glasses during the product consistency type tests. The concentration of Si in solution for all of the samples suggests that Ca and Si are co-precipitating as was evident from the decrease in Ca concentrations at short times. It is suggested that the presence of Ca in solution forms a passive reactive interface (PRI) which decreases the rate of formation of a hydrated surface layer decreasing the overall dissolution rate. The results from the geochemical modelling of the product consistency type tests showed that Ca and Si are co-precipitating at short times decreasing the normalised mass loss. This is evident from the Ca and Si phases which are most probable to precipitate out of solution as suggested by the geochemical modelling results from PhREEQC In order to understand the mechanisms of alteration layer formation of the UK HLW glasses, vapour hydration tests (VHT) were performed. Results from the time dependant VHT experiments have shown changes in the mechanisms of alteration layer formation with the addition of the simulated Blend waste to the base glasses. It was also shown that iron may be a suppressor to zinc dissolution. Both a Ca and Zn doped Blend waste glass and a base glass doped with Fe Zn and Zr did not show significant layers of zinc in the alteration layer as shown in the Ca and Zn doped base glass in both the reproducibility or time-dependant VHT experiments. Giesler et al. have similar results to the VHT results in this study, which correlate to an interface-coupled dissolution-reprecipitation mechanism when simulated Blend waste is added to the base glasses (Giesler, T. et. al., J. Non-Cryst. Solids 356 (2010) 1458). However, further.
Download or read book Does Fully Radioactive Glass Behave Differently Than Simulated Waste Glass written by and published by . This book was released on 1992 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 the use of the large amount of the data generated in the studies of simulated nuclear waste glass for the modeling of performance of radioactive glasses. Most of the previous comparison studies have been performed at a low to intermediate ratio of glass surface area to solution volume and for time periods of less than one year. These studies have generally concluded there is a little difference in leach behavior between the two glass types. This study reinvestigates that conclusion by utilizing an extensive test matrix, with SA/V ranging between 340 to 20,000 m[sup 1] on three waste glass compositions, for time periods planned up to eight years. The early results are consistent with other studies, in that the leach behavior of simulated waste glasses is similar to that of fully radioactive glasses. However, the longer-term tests at higher SA/V suggest that the leach behavior of the two types of glass diverges, under certain conditions. The longer-term comparison of the leach behavior is discussed.
Download or read book Ceramic glass radioactive waste forms written by C. R. Cooley and published by . This book was released on 1977 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Oversight written by United States. Congress. House. Committee on Science and Technology. Subcommittee on Fossil and Nuclear Energy Research, Development, and Demonstration and published by . This book was released on 1978 with total page 1170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
