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 LONG TERM TECHNETIUM INTERACTIONS WITH REDUCING CEMENTITIOUS MATERIALS written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Technetium is among the key risk drivers at the Saltstone Facility. The way that it is immobilized in this cementitious waste form is by converting its highly mobile Tc(VII) form to a much less mobile Tc(IV) form through reduction by the cement's blast furnace slag. This report includes a review of published data and experimental results dealing with Tc leaching from Portland cement waste forms. The objectives for the literature study were to document previous reports of Tc interactions with slag-containing cementitious materials. The objectives for the laboratory study were to measure Tc-saltstone Kd values under reducing conditions. From the literature it was concluded: (1) Spectroscopic evidence showed that when Tc(IV) in a slag-cement was exposed to an oxidizing environment, it will convert to the more mobile Tc(VII) species within a short time frame, 2.5 years. (2) SRS saltstone will reduce Tc(VII) in the absence of NaS or sodium dithionite in a reducing atmosphere. (3) Only trace concentrations of atmospheric oxygen (30 to 60 ppm O2; Eh 120 mV) at the high pH levels of cementitious systems is required to maintain Tc as Tc(VII). (4) Experimental conditions must be responsible for wide variability of measured K{sub d} values, such that they are either very low, ≈1 mL/g, or they are very high ≈1000 mL/g, suggesting that Tc(VII) or Tc(IV) dominate the systems. Much of this variability appears to be the result of experimental conditions, especially direct controls of oxygen contact with the sample. (5) A field study conducted at SRS in the 1980s indicated that a slag-saltstone immobilized Tc for 2.5 years. Below background concentrations of Tc leached out of the slag-containing saltstone, whereas Tc leached out of the slag-free saltstone at the rate of nitrate loss. One possible explanation for the immobilization of Tc in this study was that the slag-saltstone maintained reducing conditions within the core of the 55-gallon sample, whereas in the small-scale lab experiments, where samples were crushed to

Download or read book An Introduction to Nuclear Waste Immobilisation written by Michael I. Ojovan and published by Elsevier. This book was released on 2010-07-07 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: Safety and environmental impact is of uppermost concern when dealing with the movement and storage of nuclear waste. The 20 chapters in 'An Introduction to Nuclear Waste Immobilisation' cover all important aspects of immobilisation, from nuclear decay, to regulations, to new technologies and methods. Significant focus is given to the analysis of the various matrices used in transport: cement, bitumen and glass, with the greatest attention being given to glass. The last chapter concentrates on the performance assessment of each matrix, and on new developments of ceramics and glass composite materials, thermochemical methods and in-situ metal matrix immobilisation. The book thoroughly covers all issues surrounding nuclear waste: from where to locate nuclear waste in the environment, through nuclear waste generation and sources, treatment schemes and technologies, immobilisation technologies and waste forms, disposal and long term behaviour. Particular attention is paid to internationally approved and worldwide-applied approaches and technologies.* Each chapter focuses on a different matrix used in nuclear waste immobilisation: Cement, bitumen, glass and new materials.* Keeps the most important issues surrounding nuclear waste – such as treatment schemes and technologies, and disposal - at the forefront.

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 Chemistry and Microstructure of Solidified Waste Forms written by Roger D. Spence and published by CRC Press. This book was released on 1992-12-15 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemistry and Microstructure of Solidified Waste Forms presents a comprehensive summary of mechanisms of immobilization in cementitious waste forms and the effect of waste species on cement chemistry and morphology. The book introduces the well-known chemistry and microstructure of cement pastes, in addition to common mechanisms of immobilization of waste species in cementitious waste forms. The fundamental chemical and microstructural fate of waste species is reviewed, and a technique for studying cementitious waste forms using scanning transmission electron microscopy (STEM) is described with examples of its application. Chemistry and Microstructure of Solidified Waste Forms also presents evidence to prove that chromium in waste becomes part of the cement matrix, and the potentially harmful effect of this process is discussed. Data for interpretations are included so that other researchers can analyze the data and draw their own conclusions. The book also discusses how solubility and solubility theory can be combined with leach theory and diffusion theory to predict the leaching performance of cementitious waste forms. Chemistry and Microstructure of Solidified Waste Forms will prove invaluable to hazardous waste professionals, engineers, environmental engineers, chemical engineers, waste disposal managers, waste form developers and researchers, and regulators.

Download or read book An Introduction to Nuclear Waste Immobilisation written by Michael I Ojovan and published by Elsevier. This book was released on 2013-12-06 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Drawing on the authors' extensive experience in the processing and disposal of waste, An Introduction to Nuclear Waste Immobilisation, Second Edition examines the gamut of nuclear waste issues from the natural level of radionuclides in the environment to geological disposal of waste-forms and their long-term behavior. It covers all-important aspects of processing and immobilization, including nuclear decay, regulations, new technologies and methods. Significant focus is given to the analysis of the various matrices used, especially cement and glass, with further discussion of other matrices such as bitumen. The final chapter concentrates on the performance assessment of immobilizing materials and safety of disposal, providing a full range of the resources needed to understand and correctly immobilize nuclear waste.

Download or read book Corrosion Behavior of Technetium Waste Forms Exposed to Various Aqueous Environments written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Technetium is a long-lived beta emitter produced in high yields from uranium as a waste product in spent nuclear fuel and has a high degree of environmental mobility as pertechnetate. It has been proposed that Tc be immobilized into various metallic waste forms to prevent Tc mobility while producing a material that can withstand corrosion exposed to various aqueous medias to prevent the leachability of Tc to the environment over long periods of time. This study investigates the corrosion behavior of Tc and Tc alloyed with 316 stainless steel and Zr exposed to a variety of aqueous media. To date, there is little investigative work related to Tc corrosion behavior and less related to potential Tc containing waste forms. Results indicate that immobilizing Tc into stainless steel-zirconium alloys can be a promising technique to store Tc for long periods of time while reducing the need to separately store used nuclear fuel cladding. Initial results indicate that metallic Tc and its alloys actively corrode in all media. We present preliminary corrosion rates of 100% Tc, 10% Tc - 90% SS{sub 85%}Zr{sub 15%}, and 2% Tc - 98% SS{sub 85%}Zr{sub 15%} in varying concentrations of nitric acid and pH 10 NaOH using the resistance polarization method while observing the trend that higher concentrations of Tc alloyed to the sample tested lowers the corrosion rate of the proposed waste package.

Download or read book Technical Progress Report for the Quarter written by and published by . This book was released on with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Radionuclide and Metal Sorption on Cement and Concrete written by Michael Ochs and published by Springer. This book was released on 2016-08-23 with total page 301 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cementitious materials are being widely used as solidification/stabilisation and barrier materials for a variety of chemical and radioactive wastes, primarily due to their favourable retention properties for metals, radionuclides and other contaminants. The retention properties result from various mineral phases in hydrated cement that possess a high density and diversity of reactive sites for the fixation of contaminants through a variety of sorption and incorporation reactions. This book presents a state of the art review and critical evaluation of the type and magnitude of the various sorption and incorporation processes in hydrated cement systems for twenty-five elements relevant for a broad range of radioactive and industrial wastes. Effects of cement evolution or ageing on sorption/incorporation processes are explicitly evaluated and quantified. While the immobilisation of contaminants by mixing-in during hydration is not explicitly addressed, the underlying chemical processes are similar. A quantitative database on the solid/liquid distribution behaviour of radionuclides and other elements in hydrated cement systems is established on the basis of a consistent review and re-evaluation of literature data. In addition to recommended values, all underlying original experimental data and key experimental info rmation are provided, which allows users to trace the given recommendations or to develop their own set of key values. This database is closely tied to the safety analysis of near surface disposal of radioactive waste in Belgium. It focuses on radioelements, toxic stable elements and heavy metals, which makes it relevant for investigations involving the interaction of radioactive and conventional contaminants with cement-based barriers.

Download or read book Handbook of Advanced Radioactive Waste Conditioning Technologies written by Michael I. Ojovan and published by Elsevier. This book was released on 2011-01-24 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radioactive wastes are generated from a wide range of sources, including the power industry, and medical and scientific research institutions, presenting a range of challenges in dealing with a diverse set of radionuclides of varying concentrations. Conditioning technologies are essential for the encapsulation and immobilisation of these radioactive wastes, forming the initial engineered barrier required for their transportation, storage and disposal. The need to ensure the long term performance of radioactive waste forms is a key driver of the development of advanced conditioning technologies.The Handbook of advanced radioactive waste conditioning technologies provides a comprehensive and systematic reference on the various options available and under development for the treatment and immobilisation of radioactive wastes. The book opens with an introductory chapter on radioactive waste characterisation and selection of conditioning technologies. Part one reviews the main radioactive waste treatment processes and conditioning technologies, including volume reduction techniques such as compaction, incineration and plasma treatment, as well as encapsulation methods such as cementation, calcination and vitrification. This coverage is extended in part two, with in-depth reviews of the development of advanced materials for radioactive waste conditioning, including geopolymers, glass and ceramic matrices for nuclear waste immobilisation, and waste packages and containers for disposal. Finally, part three reviews the long-term performance assessment and knowledge management techniques applicable to both spent nuclear fuels and solid radioactive waste forms.With its distinguished international team of contributors, the Handbook of advanced radioactive waste conditioning technologies is a standard reference for all radioactive waste management professionals, radiochemists, academics and researchers involved in the development of the nuclear fuel cycle. - Provides a comprehensive and systematic reference on the various options available and under development for the treatment and immobilisation of radioactive wastes - Explores radioactive waste characterisation and selection of conditioning technologies including the development of advanced materials for radioactive waste conditioning - Assesses the main radioactive waste treatment processes and conditioning technologies, including volume reduction techniques such as compaction

Download or read book Radioactive Waste Management and Contaminated Site Clean Up written by William E Lee and published by Elsevier. This book was released on 2013-10-31 with total page 925 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radioactive waste management and contaminated site clean-up reviews radioactive waste management processes, technologies, and international experiences. Part one explores the fundamentals of radioactive waste including sources, characterisation, and processing strategies. International safety standards, risk assessment of radioactive wastes and remediation of contaminated sites and irradiated nuclear fuel management are also reviewed. Part two highlights the current international situation across Africa, Asia, Europe, and North America. The experience in Japan, with a specific chapter on Fukushima, is also covered. Finally, part three explores the clean-up of sites contaminated by weapons programmes including the USA and former USSR.Radioactive waste management and contaminated site clean-up is a comprehensive resource for professionals, researchers, scientists and academics in radioactive waste management, governmental and other regulatory bodies and the nuclear power industry. - Explores the fundamentals of radioactive waste including sources, characterisation, and processing strategies - Reviews international safety standards, risk assessment of radioactive wastes and remediation of contaminated sites and irradiated nuclear fuel management - Highlights the current international situation across Africa, Asia, Europe, and North America specifically including a chapter on the experience in Fukushima, Japan

Download or read book Stobwasser s Bilderkabinet in Berlin written by and published by . This book was released on 1986 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Materials for Nuclear Waste Immobilization written by Michael I. Ojovan and published by MDPI. This book was released on 2020-01-09 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book outlines recent advances in nuclear wasteform materials including glasses, ceramics and cements and spent nuclear fuel. It focuses on durability aspects and contains data on performance of nuclear wasteforms as well as expected behavior in a disposal environment.

Download or read book Radioactive Waste Management written by and published by . This book was released on 1981 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings of the International Conference on Radioactive Waste Management and Environmental Remediation written by and published by . This book was released on 1995 with total page 920 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fundamentals of Nuclear Pharmacy written by Gopal B. Saha and published by Springer. This book was released on 2017-11-11 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt: Currently an estimated 17 million nuclear medicine procedures are performed each year in the US and constantly evolving, as new radiopharmaceuticals and imaging techniques are introduced for better diagnosis and treatment of human diseases. In keeping up with new developments, the Seventh Edition of Fundamentals of Nuclear Pharmacy chronicles the advancements in radiopharmaceuticals and their use in clinical applications. It discusses basic concepts such as the atom, radioactive decay, instrumentation and production of radionuclides, and explores the design, labeling, characteristics and quality control of radiopharmaceuticals. Radiation regulations and diagnostic and therapeutic applications of radiopharmaceuticals are detailed. Thoroughly updated, the Seventh Edition includes new topics such as alternative productions of 99Mo; production of 64Cu, 86Y, 89Zr, 177Lu, 223Ra; synthesis and clinical uses of new radiopharmaceuticals such as DaTscan, Xofigo, Amyvid, Neuraceq, Vizamyl, Axumin and 68Ga-DOTATATE; dosimetry of new radiopharmaceuticals; theranostic agents and translational medicine. It features numerous examples, diagrams, and images to further clarify the information and offers end- of-chapter questions to help readers assess their comprehension of the material. Recognized as a classic text on nuclear chemistry and pharmacy and acclaimed for its concise and easy-to-understand presentation, Fundamentals of Nuclear Pharmacy is an authoritative resource for nuclear medicine physicians, residents, students, and technologists.