Download or read book Temperature and Pressure Effects on the Chemical Durability of Borosilicate Simulated Nuclear Waste Glass written by Michael T. Tierney and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Final Technical Report written by and published by . This book was released on 1996 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 glass properties, such as chemical durability, viscosity and electrical conductivity. These properties are very important for processing and assuring the quality and safety controls of the waste glasses. The objective of this project was to investigate the effect of water in the simulated nuclear waste glasses on various glass properties, including chemical durability, glass transition temperature, liquidus temperature, viscosity and electrical conductivity. This report summarizes the results of this investigation conducted at Rensselaer during the past one year.
Download or read book Optimization of High level Waste Loading in a Borosilicate Glass Matrix by Using Chemical Durability Modeling Approach written by Javeed Mohammad and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A laboratory scale study was carried out on a set of 6 borosilicate waste glasses made from simulated high-level nuclear waste. The test matrix was designed to explore the composition region suitable for the long-term geologic disposal of high-temperature-and high-waste-containing glasses. The glass compositions were selected to achieve maximum waste loading without a sacrifice in glass durability. The relationship between glass composition and chemical durability was examined. The qualitative effect of increasing B2O3 content on the overall waste glass leaching behavior has also been addressed. The glass composition matrix was designed by systematically varying the factors: %waste loading and (SiO2+Frit):B2O3 ratio, with (SiO2:Frit) ratio being held constant. In order to assess the chemical durability, the Product Consistency Test (ASTM C-1285) was performed. Under PCT protocol, crushed glass was allowed to react with ASTM type I water under static conditions. All leachate solutions were analyzed by the technique; Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES). A statistical regression technique was utilized to model the normalized release of the major soluble elements, Na, Si, and B, as a function of the individual as well as interactive chemical effects (B2O3, Al2O3, Fe2O3, MnO, SiO2, SrO, Na2O, B2O3*SiO2, B2O3*Al2O3, Fe2O3*Na2O, Al2O3*Na2O, and MnO*SiO2). Geochemical modeling was performed using the computer code EQ3/6 to: (1) determine the saturation states of the possible silicate minerals, a-cristobalite and chalcedony; and (2) predict the most stable mineral phase based on the mineral thermodynamic data. Mineral/water interactions were analyzed by representing the resultant glass data on a Na-Al-Si-O-H stability diagram.
Download or read book Brine Chemistry Effects on the Durability of a Simulated Nuclear Waste Glass written by and published by . This book was released on 1979 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of various solution chemistry parameters on the alteration and leaching characteristics of a copper borosilicate simulated waste glass have been determined under hydrothermal conditions. Results are presented which demonstrate that leachant salinity, volume/glass surface area ratio, pH, cation content, and dissolved SiO2 concentration effects are important. A brief explanation of these results is given which is based on ion exchange and solution saturation equilibria.
Download or read book OPTIMIZATION OF HIGH LEVEL WASTE LOADING IN A BOROSILICATE GLASS MATRIX BY USING CHEMICAL DURABILITY MODELING APPROACH written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A laboratory scale study was carried out on a set of 6 borosilicate waste glasses made from simulated high-level nuclear waste. The test matrix was designed to explore the composition region suitable for the long-term geologic disposal of high-temperature-and high-waste-containing glasses. The glass compositions were selected to achieve maximum waste loading without a sacrifice in glass durability. The relationship between glass composition and chemical durability was examined. The qualitative effect of increasing B2O3 content on the overall waste glass leaching behavior has also been addressed. The glass composition matrix was designed by systematically varying the factors: %waste loading and (SiO2+Frit):B2O3 ratio, with (SiO2:Frit) ratio being held constant. In order to assess the chemical durability, the Product Consistency Test (ASTM C-1285) was performed. Under PCT protocol, crushed glass was allowed to react with ASTM type I water under static conditions. All leachate solutions were analyzed by the technique; Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES). A statistical regression technique was utilized to model the normalized release of the major soluble elements, Na, Si, and B, as a function of the individual as well as interactive chemical effects (B2O3, Al2O3, Fe2O3, MnO, SiO2, SrO, Na2O, B2O3*SiO2, B2O3*Al2O3, Fe2O3*Na2O, Al2O3*Na2O, and MnO*SiO2). Geochemical modeling was performed using the computer code EQ3/6 to: (1) determine the saturation states of the possible silicate minerals, a-cristobalite and chalcedony; and (2) predict the most stable mineral phase based on the mineral thermodynamic data. Mineral/water interactions were analyzed by representing the resultant glass data on a Na-Al-Si-O-H stability diagram.
Download or read book Chemical durability of borosilicate glasses containing simulated high level nuclear wastes iii written by S. Hara and published by . This book was released on 1983 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Glass as a Waste Form and Vitrification Technology written by National Research Council and published by National Academies. This book was released on 1997-03-02 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical Durability of Zinc Borosilicate Nuclear Waste Glass written by and published by . This book was released on 1977 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 of glass composition as previously discussed. This discussion is limited to a representative waste glass composition, a high-zinc borosilicate formulation which has been studied in detail by Battelle Pacific Northwest Laboratories. (GHT).
Download or read book Chemical Durability of Simulated Nuclear Glasses Containing Water written by and published by . This book was released on 1995 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 differences in reactions between glass and water. In the PCT, the glass network dissolution controlled the elemental releases, and water in the glass accelerated the reaction rate. On the other hand, alkali ion exchange with hydronium played an important role in the MCC-1. For the latter, the amount of water introduced into a leached layer from ion-exchange was found to be much greater than that of initially incorporated water in the glass. Hence, the initial water content has no effect on glass dissolution as measured by the MCC-1 test.
Download or read book Chemical Durability of Simulated Nuclear Waste Glasses and Their Natural Analogues in Submarine Conditions written by Zhihong Zhou and published by . This book was released on 1989 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Transition Metal Oxide and Mixed Network Formers on Structure and Properties of Borosilicate Glasses written by Xiaonan Lu and published by . This book was released on 2018 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: First, the effect of transition metal oxide (e.g., V2O5, Co2O3, etc.) on the physical properties (e.g., density, glass transition temperature (Tg), optical properties and mechanical properties) and chemical durability of a simplified borosilicate nuclear waste glass was investigated. Adding V2O5 in borosilicate nuclear waste glasses decreases the Tg, while increasing the fracture toughness and chemical durability, which benefit the future formulation of nuclear waste glasses. Second, structural study of ZrO2/SiO2 substitution in silicate/borosilicate glasses was systematically conducted by molecular dynamics (MD) simulation and the quantitative structure-property relationships (QSPR) analysis to correlate structural features with measured properties. Third, for bioactive glass formulation, mixed-network former effect of B2O3 and SiO2 on the structure, as well as the physical properties and bioactivity were studied by both experiments and MD simulation. B2O3/SiO2 substitution of 45S5 and 55S5 bioactive glasses increases the glass network connectivity, correlating well with the reduction of bioactivity tested in vitro. Lastly, the effect of optical dopants on the optimum analytical performance on atom probe tomography (APT) analysis of borosilicate glasses was explored. It was found that optical doping could be an effective way to improve data quality for APT analysis with a green laser assisted system, while laser spot size is found to be critical for optimum performance. The combined experimental and simulation approach adopted in this dissertation led to a deeper understanding of complex borosilicate glass structures and structural origins of various properties.
Download or read book Chemical Durability of Lead Borosilicate Glass Matrix Under Simulated Geological Conditions written by Vrunda S. Yalmali and published by . This book was released on 2002 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Performing a Chemical Durability Test on Radioactive High level Nuclear Waste Glass written by and published by . This book was released on 1990 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: Savannah River Site (SRS), currently is storing (approximately)30 million gallons of highly radioactive nuclear wastes. The Defense Waste Processing Facility (DWPF) nearing completion at SRS will incorporate the radionuclides in these wastes into solid borosilicate glass for final disposal in a geologic repository. Because of the variability of the wastes in the tanks, borosilicate glasses of different compositions will be produced by the DWPF during the 20--25 years required to solidify all the wastes at SRS. A chemical durability test, the Product Consistency Test (PCT), has been developed at SRS to measure the consistency of the durability of these glasses. This paper describes the remote and hands-on procedures for performing the PCT on these radioactive glasses. Results will be presented that indicate the good precision of the PCT and indicate some of the chemistry involved in leaching radioactive elements from the glass. 9 refs., 1 fig., 4 tabs.
Download or read book The Chemical Durability of Glass written by International Commission on Glass. Sub-committee AII. and published by . This book was released on 1973 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Composition and Temperature on Viscosity and Electrical Conductivity of Borosilicate Glasses for Hanford Nuclear Waste Immobilization written by and published by . This book was released on 1993 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: Viscosity and electrical conductivity of 79 simulated borosilicate glasses in the expected range of compositions to be produced in the Hanford Waste Vitrification Plant were measured within the temperature span from 950 to 1250[degree]C. The nine major oxide components were SiO[sub 2], B[sub 2]O[sub 3], Li[sub 2]O, Na[sub 2]O, CaO, MgO, Fe[sub 2]O[sub 3], Al[sub 2]O[sub 3], and ZrO[sub 2]. The test compositions were generated statistically. The data were fitted by Fulcher and Arrhenius equations with temperature coefficients being multilinear functions of the mass fractions of the oxide components. Mixture models were also developed for the natural logarithm of viscosity and that of electrical conductivity at 1150[degree]C. Least squares regression was used to obtain component coefficients for all the models.
Download or read book Composition Effects on Chemical Durability and Viscosity of Nuclear Waste Glasses written by Xiangdong Feng and published by . This book was released on 1988 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt:
