Download or read book Evaluating the Solubility and Homogeneity of Plutonium in an Alkali Borosilicate Glass written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book PLUTONIUM SOLUBILITY IN HIGH LEVEL WASTE ALKALI BOROSILICATE GLASS written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The solubility of plutonium in a Sludge Batch 6 (SB6) reference glass and the effect of incorporation of Pu in the glass on specific glass properties were evaluated. A Pu loading of 1 wt % in glass was studied. Prior to actual plutonium glass testing, surrogate testing (using Hf as a surrogate for Pu) was conducted to evaluate the homogeneity of significant quantities of Hf (Pu) in the glass, determine the most appropriate methods to evaluate homogeneity for Pu glass testing, and to evaluate the impact of Hf loading in the glass on select glass properties. Surrogate testing was conducted using Hf to represent between 0 and 1 wt % Pu in glass on an equivalent molar basis. A Pu loading of 1 wt % in glass translated to (almost equal to)18 kg Pu per Defense Waste Processing Facility (DWPF) canister, or about 10X the current allowed limit per the Waste Acceptance Product Specifications (2500 g/m3 of glass or about 1700 g/canister) and about 30X the current allowable concentration based on the fissile material concentration limit referenced in the Yucca Mountain Project License Application (897 g/m33 of glass or about 600 g Pu/canister). Based on historical process throughput data, this level was considered to represent a reasonable upper bound for Pu loading based on the ability to provide Pu containing feed to the DWPF. The task elements included evaluating the distribution of Pu in the glass (e.g. homogeneity), evaluating crystallization within the glass, evaluating select glass properties (with surrogates), and evaluating durability using the Product Consistency Test -- Method A (PCT-A). The behavior of Pu in the melter was evaluated using paper studies and corresponding analyses of DWPF melter pour samples. The results of the testing indicated that at 1 wt % Pu in the glass, the Pu was homogeneously distributed and did not result in any formation of plutonium-containing crystalline phases as long as the glass was prepared under 'well-mixed' conditions. The incorporation of 1 wt % Pu in the glass did not adversely impact glass viscosity (as assessed using Hf surrogate) or glass durability. Finally, evaluation of DWPF glass pour samples that had Pu concentrations below the 897 g/m3 limit showed that Pu concentrations in the glass pour stream were close to targeted compositions in the melter feed indicating that Pu neither volatilized from the melt nor stratified in the melter when processed in the DWPF melter.
Download or read book VARIABILITY STUDY TO DETERMINE THE SOLUBILITY OF IMPURITIES IN PLUTONIUM BEARING LANTHANIDE BOROSILICATE GLASS written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This study focuses on the development of a compositional envelope that describes the retention of various impurities in lanthanide borosilicate (LaBS) glass for vitrification and immobilization of excess, defense-related plutonium. A limited amount of impurity data for the various plutonium sources is available and projections were made through analysis of the available information. These projections were used to define types and concentrations of impurities in the LaBS glass compositions to be fabricated and tested. Sixty surrogate glass compositions were developed through a statistically designed approach to cover the anticipated ranges of concentrations for several impurity species expected in the plutonium feeds. An additional four glass compositions containing actual plutonium oxide were selected based on their targeted concentrations of metals and anions. The glasses were fabricated and characterized in the laboratory and shielded cells facility to determine the degree of retention of the impurity components, the impact of the impurities on the durability of each glass, and the degree of crystallization that occurred, both upon quenching and slow cooling. Overall, the LaBS glass system appears to be very tolerant of most of the impurity types and concentrations projected in the plutonium waste stream. For the surrogate glasses, the measured CuO, Ga2O3, Na2O, NiO, and Ta2O5 concentrations fell very close to their target values across the ranges of concentrations targeted in this study for each of these components. The measured CaO and PbO concentrations were consistently higher than the targeted values. The measured Cr2O3 and Fe2O3 concentrations were very close to the targets except for the one highest targeted value for each of these components. A solubility limit may have been approached in this glass system for K2O and MgO. The measured Cl−, F−, SeO2 and SO42− concentrations were well below their target values for all of the study glasses. This is likely due to volatilization of these species during melting of the glass batch. Note that the degree of volatilization that occurred in this crucible-scale study may differ from the full-scale melter. The measured HfO2 concentrations were below their target values for all of the surrogate glasses. It is likely that for HfO2, the solubility limit in the glass was exceeded and some of the HfO2 batch material remained in the bottom of the crucibles after pouring the glasses. X-ray diffraction and scanning electron microscopy (SEM) results indicated that some crystalline HfO2 remained in some of the surrogate glasses with the lowest concentration of impurities. No other crystalline phases were identified. The Product Consistency Test (PCT) results showed that all 60 of the surrogate glass compositions tested were very durable, regardless of thermal history, with the highest normalized release for boron being 0.041 g/L. The pH of the leachate solutions was generally lower than that of conventional waste glasses due to the lack of alkali in the LaBS glass, which likely impacted the PCT results. The normalized release rates for the elements measured were generally too small to attempt to correlate the results with the compositions of the test glasses. The Toxicity Characteristic Leaching Procedure results showed that no hazardous metals were leached from the surrogate glasses in any measurable concentration. A plutonium-containing crystalline phase with a cross-shaped morphology was identified via SEM in the glasses fabricated with plutonium oxide. This phase was identified in a previous study of plutonium-bearing LaBS glasses and may provide an opportunity to intentionally crystallize some of the plutonium oxide into a highly insoluble form with an intrinsic neutron absorber. Additional work is necessary to better characterize the influence that this phase has on durability of the glass. The PCT results for the plutonium-containing LaBS glasses with impurities were similar to previous tests conducted on PuO2-containing glasses without impurities added. The highest normalized release for boron was 0.02 g/L, which bounded the highest normalized release for plutonium of 0.01 g/L.
Download or read book Homogeneous Glass Processing Region Defined for a Lanthanide Borosilicate Glass Composition for the Mobilization of Plutonium Using Thorium as a Surrogate written by and published by . This book was released on 1996 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: A ternary diagram showing the homogeneous glass processing region of a base frit, rare earth oxide and thorium oxide has been developed for a residence temperature of 1475 C. Thorium oxide was used as a plutonium surrogate. All ThO2 glasses that were processed included a 1:1 mole ratio of Th to Gd. Gadolinium is added to the glass as a neutron absorber. Forty individual glass compositions were melted at 1475 C for 4 to 6 hours with periodic stirring. Two glasses (B-20-25 and B-25-25) were processed with a ThO2 loading of 25 weight percent (oxide) without amorphous phase separation or crystalline species detected by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) or Transmission Electron Microscopy (TEM). These were processed with 55 weight percent frit, 20 weight percent rare earth oxides and 50 percent frit, 25 percent rare earth oxides. Crystalline species that formed outside of the homogeneous glass processing region due to solubility limits or insufficient processing temperature were identified. Amorphous phase separation was detected and examined by TEM at high ThO2 loadings (20 to 30 weight percent oxide). The base frit was able to dissolve up to 65 weight percent rare earth oxides when thorium oxide was not present. Durability testing will be performed on three glasses from three different regions of the homogeneous glass processing region. Product Consistency Test (PCT) results are pending and will be added to this document under a future revision.
Download or read book The Separation and Determination of Plutonium in Diverse Biological Samples written by Taft Yutaka Toribara and published by . This book was released on 1962 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book EVALUATION OF IMPURITY EXTREMES IN A PLUTONIUM LOADED BOROSILICATE GLASS written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A vitrification technology utilizing a lanthanide borosilicate (LaBS) glass appears to be a viable option for the disposition of excess weapons-useable plutonium that is not suitable for processing into mixed oxide (MOX) fuel. A significant effort to develop a glass formulation and vitrification process to immobilize plutonium was completed in the mid-1990s. The LaBS glass formulation was found to be capable of immobilizing in excess of 10 wt % Pu and to be tolerant of a range of impurities. To confirm the results of previous testing with surrogate Pu feeds containing impurities, four glass compositions were selected for fabrication with actual plutonium oxide and impurities. The four compositions represented extremes in impurity type and concentration. The homogeneity and durability of these four compositions were measured. The homogeneity of the glasses was evaluated using x-ray diffraction (XRD) and scanning electron microscopy coupled with energy dispersive spectroscopy (SEM/EDS). The XRD results indicated that the glasses were amorphous with no evidence of crystalline species in the glass. The SEM/EDS analyses did show the presence of some undissolved PuO2 material. The EDS spectra indicated that some of the PuO2 crystals also contained hafnium oxide. The SEM/EDS analyses showed that there were no heterogeneities in the glass due to the feed impurities. The durability of the glasses was measured using the Product Consistency Test (PCT). The PCT results indicated that the durability of Pu impurity glasses was comparable with Pu glasses without impurities and significantly more durable than the Environmental Assessment (EA) glass used as the benchmark for repository disposition of high-level waste (HLW) glasses.
Download or read book Scientific Basis for Nuclear Waste Management XX Volume 465 written by Walter J. Gray and published by . This book was released on 1997-07 with total page 1398 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book features scientific research that supports the safe and effective disposal of radioactive waste in a geological repository. One highlight of the volume is the opening talk by Rustum Roy, who was instrumental in establishing the first symposium on this topic in 1978. Professor Roy summarizes his views of the past 19 years of progress in the field. A second highlight is the participation by several Russian and Ukrainian scientists who authored papers on nuclear waste disposal aspects of the Chernobyl Unit 4 reactor that exploded in April 1986. Additional topics include: glass formulations and properties; glass/water interactions; cements in radioactive waste management; ceramic and crystalline waste forms; spent nuclear fuel; waste processing and treatment; radiation effects in ceramics, glasses and nuclear waste materials; waste package materials; radionuclide solubility and speciation; radionuclide sorption; radionuclide transport; repository backfill; performance assessment; natural analogues and excess plutonium dispositioning.
Download or read book Scientific Basis for Nuclear Waste Management written by and published by . This book was released on 1997 with total page 1400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ceramic Abstracts written by and published by . This book was released on 1998 with total page 1040 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1974 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Chemistry of Glasses written by A. Paul and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 301 pages. Available in PDF, EPUB and Kindle. Book excerpt: 'The preface ... either serves for the explanation of the purpose of the book, or for justification and as an answer to critics'. Lermontov This book is based mainly on the lectures on the Chemistry of Glasses which I gave at the University of Sheffield to the final year honours and postgraduate students of Glass Technology and Materials Science. Most books reflect the interests and enthusiasm of their authors, and the present one is no exception. The chemistry of glass is a rapidly developing field because the frontiers of advanced chemistry and advanced physics are merging together and con sequently this book will soon require considerable amplification and modification. However, my experience in teaching the chemistry of glasses for more than a decade has shown me that there is much need for a good text-book on the subject. This book is therefore intended to be a stop-gap which, until it receives that new revision. may serve as a useful reference work for students and research workers alike. I gratefully acknowledge the influence on my thinking of many of those colleagues at Sheffield with whom I have been in contact during the past twenty years or so. In addition to these personal influences, other published works have had considerable influence in modifying my approach. especially Cotton and Wilkinson's Advanced inorganic Chemistry. Dr Peter James helped me in writing Chapter 2, and Professor Peter McMillan not only read the whole manuscript but also made a number of most helpful suggestions.
Download or read book Nuclear Waste Conditioning written by France. Commissariat à l'énergie atomique (CEA) and published by Le Moniteur Editions. This book was released on 2009 with total page 160 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 Energy Research Abstracts written by and published by . This book was released on 1994 with total page 762 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plutonium Deadly Gold of the Nuclear Age written by Howard Hu and published by . This book was released on 1992 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Radioactive Waste Management written by and published by . This book was released on 1995-11 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt:
