Download or read book The Incorporation of Technetium Into a Representative Low activity Waste Glass written by and published by . This book was released on 1997 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: A glass that has been tested to understand the corrosion behavior of waste glasses with high soda contents for immobilizing Hanford incidental wastes has been made by melting crushed glass with either TcO2 or NaTcO4 at 1,100--1,300 C. Incorporation of technetium in the glass was affected by solubility or kinetic effects. Metallic technetium inclusions formed in all the TcO2-doped glasses. Inclusions also formed in glasses with added NaTcO4 that were melted at 1,100 C, but a glass melted at 1,200 C did not contain detectable inclusions. The presence of Tc-bearing inclusions complicates the interpretation of results from dissolution tests because of the simultaneous release of technetium from more than one phase, the unknown surface areas of each phase, and the possible incorporation of technetium that is released from one phase into another phase. A glass containing about 0.15 mass % Tc dissolved in the glass is being used in dissolution tests to study the release behavior of technetium.
Download or read book Technetium Incorporation in Glass for the Hanford Tank Waste Treatment and Immobilization Plant written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A priority of the United States Department of Energy (U.S. DOE) is to dispose of nuclear wastes accumulated in 177 underground tanks at the Hanford Nuclear Reservation in eastern Washington State. These nuclear wastes date from the Manhattan Project of World War II and from plutonium production during the Cold War. The DOE plans to separate high-level radioactive wastes from low activity wastes and to treat each of the waste streams by vitrification (immobilization of the nuclides in glass) for disposal. The immobilized low-activity waste will be disposed of here at Hanford and the immobilized high-level waste at the national geologic repository. Included in the inventory of highly radioactive wastes is large volumes of 99Tc (~9 × 10E2 TBq or ~2.5 × 104 Ci or ~1500 kg). A problem facing safe disposal of Tc-bearing wastes is the processing of waste feed into in a chemically durable waste form. Technetium incorporates poorly into silicate glass in traditional glass melting. It readily evaporates during melting of glass feeds and out of the molten glass, leading to a spectrum of high-to-low retention (ca. 20 to 80%) in the cooled glass product. DOE-ORP currently has a program at Pacific Northwest National Laboratory (PNNL), in the Department of Materials Science and Engineering at Rutgers University and in the School of Mechanical and Materials Engineering at Washington State University that seeks to understand aspects of Tc retention by means of studying Tc partitioning, molten salt formation, volatilization pathways, and cold cap chemistry. Another problem involves the stability of Tc in glass in both the national geologic repository and on-site disposal after it has been immobilized. The major environmental concern with 99Tc is its high mobility in addition to a long half-life (2.1×105 yrs). The pertechnetate ion (TcO4- ) is highly soluble in water and does not adsorb well onto the surface of minerals and so migrates nearly at the same velocity as groundwater. Long-term corrosion of glass waste forms is an area of current interest to the DOE, but attention to the release of Tc from glass has been little explored. It is expected that the release of Tc from glass should be highly dependent on the local glass structure as well as the chemistry of the surrounding environment, including groundwater pH. Though the speciation of Tc in glass has been previously studied, and the Tc species present in waste glass have been previously reported, environmental Tc release mechanisms are poorly understood. The recent advances in Tc chemistry that have given rise to an understanding of incorporation in the glass giving rise to significantly higher single-pass retention during vitrification are presented. Additionally, possible changes to the baseline flowsheet that allow for relatively minor volumes of Tc reporting to secondary waste treatment will be discussed.
Download or read book Localized Chemistry of 99Tc in Simulated Low Activity Waste Glass written by Jamie L. Weaver and published by . This book was released on 2016 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: A priority of the United States Department of Energy (DOE) is to dispose of the nuclear waste accumulated in the underground tanks at the Hanford Nuclear Reservation in Richland, WA. Incorporation and stabilization of technetium (99Tc) from these tanks into vitrified waste forms is a concern to the waste glass community and DOE due to 99Tc's long half-life (~2.13·105 y), and its high mobility in the subsurface environment under oxidizing conditions. Working in collaboration with researchers at Pacific Northwest National Laboratory (PNNL) and other national laboratories, plans were formulated to obtain first-of-a-kind chemical structure determination of poorly understood and environmentally relevant technetium compounds that relate to the chemistry of the Tc in nuclear waste glasses. Knowledge of the structure and spectral signature of these compounds aid in refining the understanding of 99Tc incorporation into and release from oxide based waste glass. In this research a first-of-its kind mechanism for the behavior of 99Tc during vitrification is presented, and the structural role of Tc(VII) and (IV) in borosilicate waste glasses is readdressed.
Download or read book Environmental Issues and Waste Management Technologies in the Ceramic and Nuclear Industries written by and published by . This book was released on 1998 with total page 736 pages. Available in PDF, EPUB and Kindle. Book excerpt: Consists of proceedings of various symposia held during the Annual Meeting of the American Ceramic Society.
Download or read book Technetium Immobilization Forms Literature Survey written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Of the many radionuclides and contaminants in the tank wastes stored at the Hanford site, technetium-99 (99Tc) is one of the most challenging to effectively immobilize in a waste form for ultimate disposal. Within the Hanford Tank Waste Treatment and Immobilization Plant (WTP), the Tc will partition between both the high-level waste (HLW) and low-activity waste (LAW) fractions of the tank waste. The HLW fraction will be converted to a glass waste form in the HLW vitrification facility and the LAW fraction will be converted to another glass waste form in the LAW vitrification facility. In both vitrification facilities, the Tc is incorporated into the glass waste form but a significant fraction of the Tc volatilizes at the high glass-melting temperatures and is captured in the off-gas treatment systems at both facilities. The aqueous off-gas condensate solution containing the volatilized Tc is recycled and is added to the LAW glass melter feed. This recycle process is effective in increasing the loading of Tc in the LAW glass but it also disproportionally increases the sulfur and halides in the LAW melter feed which increases both the amount of LAW glass and either the duration of the LAW vitrification mission or the required supplemental LAW treatment capacity.
Download or read book ISIAME 2008 written by Ernö Kuzmann and published by Springer Science & Business Media. This book was released on 2009-06-16 with total page 593 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the International Symposium on the Industrial Applications of the Mössbauer Effect (ISIAME 2008) held in Budapest, Hungary, 17-22 August 2008 E. Kuzmann and K. Lázár (Eds.) This book provides an excellent overview on the most recent results on the industrial applications of Mössbauer spectroscopy attained on the fields of nanotechnology, metallurgy, biotechnology and pharmaceutical industry, applied mineralogy, energy production industry (coal, oil, nuclear, solar, etc.), computer industry, space technology, electronic and magnetic devices technology, ion implantation technology, including topics like characterization of novel construction materials, electronic components and magnetic materials, composite materials, colloids, amorphous and nanophase materials, small particles, coatings, interfaces, thin films and multilayers, catalysis, corrosion, tribology, surface modification, hydrogen storage, ball milling, radiation effects, electrochemistry, batteries, etc. From the various reports a broad overview emerges illustrating that the method can successfully be applied in a wide variety of topics.
Download or read book Options for the Separation and Immobilization of Technetium written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Among radioactive constituents present in the Hanford tank waste, technetium-99 (Tc) presents a unique challenge in that it is significantly radiotoxic, exists predominantly in the liquid low-activity waste (LAW), and has proven difficult to effectively stabilize in a waste form for ultimate disposal (see Figure S-1). Within the Hanford Tank Waste Treatment and Immobilization Plant, the LAW fraction will be converted to a glass waste form in the LAW vitrification facility but a significant fraction of Tc volatilizes at the high glass-melting temperatures and is captured in the off-gas treatment system. This necessitates recycle of the off-gas condensate solution to the LAW glass melter feed. The recycle process is effective in increasing the loading of Tc in the immobilized LAW (ILAW), but it also disproportionately increases the sulfur and halides in the LAW melter feed, which have limited solubility in the LAW glass and thus significantly reduce the amount of LAW (glass waste loading) that can be vitrified and still maintain good waste form properties. This increases both the amount of LAW glass and either the duration of the LAW vitrification mission or requires the need for supplemental LAW treatment capacity.
Download or read book Strategy and Methodology for Radioactive Waste Characterization written by International Atomic Energy Agency and published by IAEA. This book was released on 2007 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade significant progress has been achieved in the development of waste characterization and control procedures and equipment as a direct response to ever-increasing requirements for quality and reliability of information on waste characteristics. Failure in control procedures at any step can have important, adverse consequences and may result in producing waste packages which are not compliant with the waste acceptance criteria for disposal, thereby adversely impacting the repository. The information and guidance included in this publication corresponds to recent achievements and reflects the optimum approaches, thereby reducing the potential for error and enhancing the quality of the end product. -- Publisher's description.
Download or read book Radioactive Waste Forms for the Future written by Werner Lutze and published by North Holland. This book was released on 1988 with total page 802 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents a compilation of important information on the full range of radioactive waste forms that have been developed, or at least suggested, for the incorporation of high-level nuclear waste. Many of the results were published in the ''gray literature'' of final reports of national laboratories or in various, generally less available, proceedings volumes. This is the first publication to draw information on nuclear waste forms for high-level wastes together into a single volume. Although borosilicate glass has become the standard waste form, additional research in this compound is still necessary. With improved technology (particularly processing technologies) and with a more detailed knowledge of repository conditions, glasses and second generation waste forms with improved performance properties can be developed. Sustained research programs on nuclear waste form development will yield results that can only add to public confidence and the final, safe disposal of nuclear waste. The aim of this volume is to provide a 'spring board' for these future research efforts. A detailed presentation is given on the properties and performance of non-crystalline waste forms (borosilicate glass, sintered glass, and lead-iron phosphate glass), and crystalline waste forms (Synroc, tailored ceramics, TiO 2 - ceramic matrix, glass-ceramics and FUETAP concrete). A chapter on Novel Waste Forms reviews a number of methods that warrant further development because of their potential superior performance and unique applications. The final chapter includes a tabulated comparison of important waste form properties and an extended discussion on the corrosion process and radiation damage effects for each waste form. Of particular interest is a performance assessment of nuclear waste borosilicate glass and the crystalline ceramic Synroc. This is the first detailed attempt to compare these two important waste forms on the basis of their materials properties. The discussion emphasizes the difficulties in making such a comparison and details the types of data that are required. Each chapter has been written by an expert and includes a current compilation of waste form properties with an extensive list of references. This volume will provide a stimulus for future research as well as useful reference material for scientists working in the field of nuclear waste disposal and materials science.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1989 with total page 780 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy Research Abstracts written by and published by . This book was released on 1992 with total page 812 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiannual, with semiannual and annual indexes. References to all scientific and technical literature coming from DOE, its laboratories, energy centers, and contractors. Includes all works deriving from DOE, other related government-sponsored information, and foreign nonnuclear information. Arranged under 39 categories, e.g., Biomedical sciences, basic studies; Biomedical sciences, applied studies; Health and safety; and Fusion energy. Entry gives bibliographical information and abstract. Corporate, author, subject, report number indexes.
Download or read book Chemical Precipitation Processes for the Treatment of Aqueous Radioactive Waste written by and published by . This book was released on 1992 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this report is to provide a review of chemical precipitation processes for the treatment of low and intermediate level aqueous waste. It supersedes Technical Reports Series No. 89, Chemical Treatment of Radioactive Wastes, published in 1968. It provides data on the performance of existing plants and on improved processes that are in an advanced state of development.
Download or read book Waste Forms Technology and Performance written by National Research Council and published by National Academies Press. This book was released on 2011-09-05 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Department of Energy's Office of Environmental Management (DOE-EM) is responsible for cleaning up radioactive waste and environmental contamination resulting from five decades of nuclear weapons production and testing. A major focus of this program involves the retrieval, processing, and immobilization of waste into stable, solid waste forms for disposal. Waste Forms Technology and Performance, a report requested by DOE-EM, examines requirements for waste form technology and performance in the cleanup program. The report provides information to DOE-EM to support improvements in methods for processing waste and selecting and fabricating waste forms. Waste Forms Technology and Performance places particular emphasis on processing technologies for high-level radioactive waste, DOE's most expensive and arguably most difficult cleanup challenge. The report's key messages are presented in ten findings and one recommendation.
Download or read book Cementitious Materials for Nuclear Waste Immobilization written by Rehab O. Abdel Rahman and published by John Wiley & Sons. This book was released on 2014-11-17 with total page 245 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cementitious materials are an essential part in any radioactive waste disposal facility. Conditioning processes such as cementation are used to convert waste into a stable solid form that is insoluble and will prevent dispersion to the surrounding environment. It is incredibly important to understand the long-term behavior of these materials. This book summarises approaches and current practices in use of cementitious materials for nuclear waste immobilisation. It gives a unique description of the most important aspects of cements as nuclear waste forms: starting with a description of wastes, analyzing the cementitious systems used for immobilization and describing the technologies used, and ending with analysis of cementitious waste forms and their long term behavior in an envisaged disposal environment. Extensive research has been devoted to study the feasibility of using cement or cement based materials in immobilizing and solidifying different radioactive wastes. However, these research results are scattered. This work provides the reader with both the science and technology of the immobilization process, and the cementitious materials used to immobilize nuclear waste. It summarizes current knowledge in the field, and highlights important areas that need more investigation. The chapters include: Introduction, Portland cement, Alternative cements, Cement characterization and testing, Radioactive waste cementation, Waste cementation technology, Cementitious wasteform durability and performance assessment.
Download or read book Disposition of High Level Waste and Spent Nuclear Fuel written by National Research Council and published by National Academies Press. This book was released on 2001-07-05 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt: Focused attention by world leaders is needed to address the substantial challenges posed by disposal of spent nuclear fuel from reactors and high-level radioactive waste from processing such fuel. The biggest challenges in achieving safe and secure storage and permanent waste disposal are societal, although technical challenges remain. Disposition of radioactive wastes in a deep geological repository is a sound approach as long as it progresses through a stepwise decision-making process that takes advantage of technical advances, public participation, and international cooperation. Written for concerned citizens as well as policymakers, this book was sponsored by the U.S. Department of Energy, U.S. Nuclear Regulatory Commission, and waste management organizations in eight other countries.
Download or read book Medical Isotope Production Without Highly Enriched Uranium written by National Research Council and published by National Academies Press. This book was released on 2009-06-27 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the product of a congressionally mandated study to examine the feasibility of eliminating the use of highly enriched uranium (HEU2) in reactor fuel, reactor targets, and medical isotope production facilities. The book focuses primarily on the use of HEU for the production of the medical isotope molybdenum-99 (Mo-99), whose decay product, technetium-99m3 (Tc-99m), is used in the majority of medical diagnostic imaging procedures in the United States, and secondarily on the use of HEU for research and test reactor fuel. The supply of Mo-99 in the U.S. is likely to be unreliable until newer production sources come online. The reliability of the current supply system is an important medical isotope concern; this book concludes that achieving a cost difference of less than 10 percent in facilities that will need to convert from HEU- to LEU-based Mo-99 production is much less important than is reliability of supply.
Download or read book Joint Replacement Technology written by Peter A. Revell and published by Woodhead Publishing. This book was released on 2021-07-28 with total page 726 pages. Available in PDF, EPUB and Kindle. Book excerpt: The third edition of Joint Replacement Technology provides a thoroughly updated review of recent developments in joint replacement technology. Joint replacement is a standard treatment for joint degradation and has improved the quality of life of millions of patients. Collaboration between clinicians and researchers is critical to its continued success and to meet the rising expectations of patients and surgeons.This edition covers a range of updated and new content, ranging from chapters on materials analysis and selection, to methodologies and techniques used for joint replacement and clinical challenges of replacing specific joints. Key topics include tribological considerations and experiments; challenges in joint bearing surfaces; cementless fixation techniques; healing responses to implants. Clinical challenges and perspectives are covered with the aid of case studies.Thanks to its widespread collaboration and international contributors, Joint Replacement Technology, Third Edition is useful for materials scientists and engineers in both academia and the biomedical industry. Chemists, clinicians, and other researchers in this area will also find this text invaluable. - This third edition provides an updated comprehensive review of recent developments in joint replacement technology - Reviews a range of specific joints, biological and mechanical issues and fixation techniques - Includes revised and new content, such as sections on regulatory affairs, AI techniques and 3D printing
