Download or read book Durability of Defense Waste Processing Facility Glasses Within the Purex Range of Compositions written by and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Glass Durability Along the Compositional Continuum Between a Phase Separated Frit and a Homogeneous Glass written by and published by . This book was released on 1999 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seven non-radioactive glass compositions spanning the range of wastes to be processed in the Defense Waste Processing Facility (DWPF) were studied prior to start up of the Processing DWPF melter. These glasses were produced by Corning Glass Works and were designated Waste Compliance Plan (WCP) glasses. New glasses were melted by adding Frit 202 to the WCP-Purex glass and the resulting glass compositions were examined for amorphous phase separation using Transmission Electron Microscopy (TEM). The durability of the glasses was measured using the Product Consistency Test (PCT), ASTM C 1285-94.
Download or read book Glass Durability Along the Compositional Continuum Between a Phase Separated Frit and a Homogenous Glass written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Seven non-radioactive glass compositions spanning the range of wastes to be processed in the Defense Waste Processing Facility (DWPF) were studied prior to start up of the Processing DWPF melter. These glasses were produced by Corning Glass Works and were designated Waste Compliance Plan (WCP) glasses. New glasses were melted by adding Frit 202 to the WCP-Purex glass and the resulting glass compositions were examined for amorphous phase separation using Transmission Electron Microscopy (TEM). The durability of the glasses was measured using the Product Consistency Test (PCT), ASTM C 1285-94.
Download or read book Effect of Melter Residence Time and Temperature on Defense Waste Processing Facility Glass Durability written by and published by . This book was released on 1994 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Phase Stability Determinations of DWPF Waste Glasses Defense Waste Processing Facility written by and published by . This book was released on 1992 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: The high-level radioactive wastes stored at Savannah River, will be immobilized in borosilicate glass in the Defense Waste Processing Facility (DWPF). Waste Acceptance Preliminary Specifications require that time-temperature-transformation (TTT) curves be provided for expected DWPF compositions, in order to predict the durability of the waste form. In order to derive these TTT curves, samples of simulated glasses are being heat treated and then analyzed. The seven simulated glasses include blend, high aluminum (HM) and high iron (Purex). X-ray diffraction show minimal crystallization for the heat treatments at 400, 1000 and 1100 C; 600 and 700 C produce the greatest amount of crystallization. Scanning electron microscopy show heterogeneous crystallization with the spinel forming on melt insolubles and the acmite nucleating on the spinel. Initial leaching results show that the glass durability decreases with increasing crystallinity for the 700 C glasses. Future plans are outlined. 2 tables, 9 refs. (DLC).
Download or read book Production and Remediation of Low Sludge Simulated Purex Waste Glasses 2 written by and published by . This book was released on 1993 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Glass produced during the Purex 4 campaigns of the Integrated DWPF Melter System (IDMS) and the 774 Research Melter contained a lower fraction of sludge components than targeted by the Product Composition Control System (PCCS). Purex 4 glass was more durable than the benchmark (EA) glass, but was less durable than most other simulated SRS high-level waste glasses. Further, the measured durability of Purex 4 glass was not as well correlated with the durability predicted from the DWPF process control algorithm, probably because the algorithm was developed to predict the durability of SRS high-level waste glasses with higher sludge content than Purex 4. A melter run, designated Purex 4 Remediation, was performed using the 774 Research Melter to determine if the initial PCCS target composition determined for Purex 4 would produce acceptable glass whose durability could be accurately modeled by the DWPF glass durability algorithm. Reagent grade oxides and carbonates were added to Purex 4 melter feed stock to simulate a higher sludge loading. Each canister of glass produced was sampled and the glass durability was determined by the Product Consistency Test method. This document details the durability data and subsequent analysis.
Download or read book The Effect of Adding Crystalline Silicotitanate on the Durability Liquidus and Viscosity of Simulated High level Waste Glasses at Savannah River Site written by and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report provides a summary of the results obtained for a limited variability study for glasses containing Crystalline Silicotitanate (CST), Monosodium Titanate (MST), and either simulated Purex or HM sludge. Twenty-two glasses containing Purex sludge and three glasses containing HM sludge were fabricated and tested. The fabricated glasses were tested for durability using the 7-day Product Consistency Test (PCT) and characterized by measuring the viscosity at 1,150 C and by determining an approximate, bounding liquidus temperature. The current models used by Defense Waste Processing Facility (DWPF) for predicting durability, viscosity, and liquidus temperature were applied to all 25 glasses. The goal of this work was to identify any major problems from a glass perspective, within the scope of this effort, which could potentially preclude the use of CST at DWPF.
Download or read book Production and Remediation of Low sludge Simulated Purex Waste Glasses 1 written by and published by . This book was released on 1993 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: Glass produced during the Purex 4 campaigns of the Integrated Defense Waste Processing Facility (DWPF) Melter System (IDMS) and the 774 Research Melter contained a lower fraction of sludge components than targeted by the Product Composition Control System (PCCS). Purex 4 glass was more durable than the benchmark (EA) glass, but less durable than most simulated SRS high-level waste glasses. Also, Purex 4 glass was considerably less durable than predicted by the algorithm which will be used to control production of DWPF glass. A melter run was performed using the 774 Research Melter to determine if the initial PCCS target composition determined for Purex 4 would produce acceptable glass whose durability could be accurately modeled by Hydration Thermodynamics. Reagent grade oxides and carbonates were added to Purex 4 melter feed stock to simulate a higher sludge loading. Each canister of glass produced was sampled and the composition, crystallinity, and durability was determined. This document details the melter operation and composition and crystallinity analyses.
Download or read book The Effect of Chemical Composition on the PCT Durability of Mixed Waste Glasses from Wastewater Treatment Sludges written by and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Glass Composition on Waste Form Durability written by and published by . This book was released on 1994 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report reviews literature concerning the relationship between the composition and durability of silicate glasses, particularly glasses proposed for immobilization of radioactive waste. Standard procedures used to perform durability tests are reviewed. It is shown that tests in which a low-surface area sample is brought into contact with a very large volume of solution provide the most accurate measure of the intrinsic durability of a glass composition, whereas high-surface area/low-solution volume tests are a better measure of the response of a glass to changes in solution chemistry induced by a buildup of glass corrosion products. The structural chemistry of silicate and borosilicate glasses is reviewed to identify those components with the strongest cation-anion bonds. A number of examples are discussed in which two or more cations engage in mutual bonding interactions that result in minima or maxima in the rheologic and thermodynamic properties of the glasses at or near particular optimal compositions. It is shown that in simple glass-forming systems such interactions generally enhance the durability of glasses. Moreover, it is shown that experimental results obtained for simple systems can be used to account for durability rankings of much more complex waste glass compositions. Models that purport to predict the rate of corrosion of glasses in short-term durability tests are evaluated using a database of short-term durability test results for a large set of glass compositions. The predictions of these models correlate with the measured durabilities of the glasses when considered in large groupings, but no model evaluated in this review provides accurate estimates of durability for individual glass compositions. Use of these models in long-term durability models is discussed. 230 refs.
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 Durability of Glasses from the Hg doped Integrated DWPF Melter System IDMS Campaign written by and published by . This book was released on 1992 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Integrated DWPF Melter System (IDMS) for the vitrification of high-level radioactive wastes is designed and constructed to be a 1/9th scale prototype of the full scale Defense Waste Processing Facility (DWPF) melter. The IDMS facility is the first engineering scale melter system capable of processing mercury, and flowsheet levels of halides and noble metals. In order to determine the effects of mercury on the feed preparation process, the off-gas chemistry, glass melting behavior, and glass durability, a three-run mercury (Hg) campaign was conducted. The glasses produced during the Hg campaign were composed of Batch 1 sludge, simulated precipitate hydrolysis aqueous product (PHA) from the Precipitate Hydrolysis Experimental Facility (PHEF), and Frit 202. The glasses were produced using the DWPF process/product models for glass durability, viscosity, and liquidus. The durability model indicated that the glasses would all be more durable than the glass qualified in the DWPF Environmental Assessment (EA). The glass quality was verified by performing the Product Consistency Test (PCT) which was designed for glass durability testing in the DWPF.
Download or read book Specimen animadversionum in epistolam syricacam Semeonis Beth Arsamensisde Barsauma episcopo Nisibeno deque haeresi Nestorianorum written by and published by . This book was released on 1788 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Technical Note written by and published by . This book was released on 1996 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development of an ASTM Standard Glass Durability Test the Product Consistency Test PCT for High Level Radioactive Waste Glass written by and published by . This book was released on 1994 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The nation's first, and the world's largest, facility to immobilize high-level nuclear waste in durable borosilicate glass has started operation at the Savannah River Site (SRS) in Aiken, South Carolina. The product specifications on the glass wasteform produced in the Defense Waste Processing Facility (DWPF) required extensive characterization of the glass product before actual production began and for continued characterization during production. To aid in this characterization, a glass durability (leach) test was needed that was easily reproducible, could be performed remotely on highly radioactive samples, and could yield results rapidly. Several standard leach tests were examined with a variety of test configurations. Using existing tests as a starting point, the DWPF Product Consistency Test (PCT was developed in which crushed glass samples are exposed to 90 " 2°C deionized water for seven days. Based on extensive testing, including a seven-laboratory round robin and confirmatory testing with radioactive samples, the PCT is very reproducible, yields reliable results rapidly, and can be performed in shielded cell facilities with radioactive samples.
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:
