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Sample records for hlw glass prepared

  1. HLW immobilization in glass

    Leroy, P.; Jacquet-Francillon, N.; Runge, S.

    1992-01-01

    The immobilization of High Level Waste in glass in France is a long history which started as early as in the 1950's. More than 30 years of Research and Development have been invested in that field. Two industrial facilities are operating (AVM and R7) and a third one (T7), under cold testing, is planned to start active operation in the mid-92. While vitrification has been demonstrated to be an industrially mastered process, the question of the quality of the final waste product, i.e. the HLW glass, must be addressed. The scope of the present paper is to focus on the latter point from both standpoints of the R and D and of the industrial reality

  2. SOURCE TERMS FOR HLW GLASS CANISTERS

    J.S. Tang

    2000-01-01

    This calculation is prepared by the Monitored Geologic Repository (MGR) Waste Package Design Section. The objective of this calculation is to determine the source terms that include radionuclide inventory, decay heat, and radiation sources due to gamma rays and neutrons for the high-level radioactive waste (HLW) from the, West Valley Demonstration Project (WVDP), Savannah River Site (SRS), Hanford Site (HS), and Idaho National Engineering and Environmental Laboratory (INEEL). This calculation also determines the source terms of the canister containing the SRS HLW glass and immobilized plutonium. The scope of this calculation is limited to source terms for a time period out to one million years. The results of this calculation may be used to carry out performance assessment of the potential repository and to evaluate radiation environments surrounding the waste packages (WPs). This calculation was performed in accordance with the Development Plan ''Source Terms for HLW Glass Canisters'' (Ref. 7.24)

  3. HLW Glass Studies: Development of Crystal-Tolerant HLW Glasses

    Matyas, Josef; Huckleberry, Adam R.; Rodriguez, Carmen P.; Lang, Jesse B.; Owen, Antionette T.; Kruger, Albert A.

    2012-04-02

    In our study, a series of lab-scale crucible tests were performed on designed glasses of different compositions to further investigate and simulate the effect of Cr, Ni, Fe, Al, Li, and RuO2 on the accumulation rate of spinel crystals in the glass discharge riser of the HLW melter. The experimental data were used to expand the compositional region covered by an empirical model developed previously (Matyáš et al. 2010b), improving its predictive performance. We also investigated the mechanism for agglomeration of particles and impact of agglomerates on accumulation rate. In addition, the TL was measured as a function of temperature and composition.

  4. HIGH ALUMINUM HLW GLASSES FOR HANFORD'S WTP

    Kruger, A.A.; Joseph, I.; Bowman, B.W.; Gan, H.; Kot, W.; Matlack, K.S.; Pegg, I.L

    2009-01-01

    achievements of this program with emphasis on the recent enhancements in Al 2 O 3 loadings in HLW glass and its processing characteristics. Glass formulation development included crucible-scale preparation and characterization of glass samples to assess compliance with all melt processing and product quality requirements, followed by small-scale screening tests to estimate processing rates. These results were used to down-select formulations for subsequent engineering-scale melter testing. Finally, further testing was performed on the DM1200 vitrification system installed at VSL, which is a one-third scale (1.20 m 2 ) pilot melter for the WTP HLW melters and which is fitted with a fully prototypical off-gas treatment system. These tests employed glass formulations with high waste loadings and Al 2 O 3 contents of ∼25 wt%, which represents a near-doubling of the present WTP baseline maximum Al 2 O 3 loading. In addition, these formulations were processed successfully at glass production rates that exceeded the present requirements for WTP HLW vitrification by up to 88%. The higher aluminum loading in the HLW glass has an added benefit in that the aluminum leaching requirements in pretreatment are reduced, thus allowing less sodium addition in pretreatment, which in turn reduces the amount of LAW glass to be produced at the WTP. The impact of the results from this ORP program in reducing the overall cost and schedule for the Hanford waste treatment mission will be discussed

  5. Database and Interim Glass Property Models for Hanford HLW Glasses

    Hrma, Pavel R; Piepel, Gregory F; Vienna, John D; Cooley, Scott K; Kim, Dong-Sang; Russell, Renee L

    2001-01-01

    The purpose of this report is to provide a methodology for an increase in the efficiency and a decrease in the cost of vitrifying high-level waste (HLW) by optimizing HLW glass formulation. This methodology consists in collecting and generating a database of glass properties that determine HLW glass processability and acceptability and relating these properties to glass composition. The report explains how the property-composition models are developed, fitted to data, used for glass formulation optimization, and continuously updated in response to changes in HLW composition estimates and changes in glass processing technology. Further, the report reviews the glass property-composition literature data and presents their preliminary critical evaluation and screening. Finally the report provides interim property-composition models for melt viscosity, for liquidus temperature (with spinel and zircon primary crystalline phases), and for the product consistency test normalized releases of B, Na, and Li. Models were fitted to a subset of the screened database deemed most relevant for the current HLW composition region

  6. Influence of Glass Property Restrictions on Hanford HLW Glass Volume

    Kim, Dong-Sang; Vienna, John D.

    2001-01-01

    A systematic evaluation of Hanford High-Level Waste (HLW) loading in alkali-alumino-borosilicate glasses was performed. The waste feed compositions used were obtained from current tank waste composition estimates, Hanford's baseline retrieval sequence, and pretreatment processes. The waste feeds were sorted into groups of like composition by cluster analysis. Glass composition optimization was performed on each cluster to meet property and composition constraints while maximizing waste loading. Glass properties were estimated using property models developed for Hanford HLW glasses. The impacts of many constraints on the volume of HLW glass to be produced at Hanford were evaluated. The liquidus temperature, melting temperature, chromium concentration, formation of multiple phases on cooling, and product consistency test response requirements for the glass were varied one- or many-at-a-time and the resultant glass volume was calculated. This study shows clearly that the allowance of crystalline phases in the glass melter can significantly decrease the volume of HLW glass to be produced at Hanford.

  7. Preparation and characterization of an improved borosilicate glass for the solidification of high level radioactive fission product solutions (HLW). Pt. 2

    Kahl, L.; Ruiz-Lopez, M.C.; Saidl, J.; Dippel, T.

    1982-04-01

    In the 'Institut fuer Nuklare Entsorgungstechnik' the borosilicate glass VG 98/12 has been developed for the solidification of the high level radioactive waste (HLW). This borosilicate glass can be used in a direct heated ceramic melter and forms together with the HLW the borosilicate glass product GP 98/12. This borosilicate glass product has been examined in detail both in liquid and solid state. The elements contained in the HLW can be incorporated without problems. Only in a few exceptions the concentration must be kept below certain limits to exclude the formation of a second phase ('yellow phase') by separation. No spontaneous crystallization and no crystallization over a long time could be observed as long as the temperature of the borosilicate glass product is kept below its transformation area. Simulating accidental conditions in the final storage, samples had been leached at temperatures up to 200 0 C and pressures up to 130 bar with saturated rock salt brine and saturated quinary salt brine. The leaching process seems to be stopped by the formed 'leached layer' on the surface of the borosilicate glass product after a limited leaching time. Detailed investigations have been started to explain this phenomenon. (orig.) [de

  8. HLW immobilization in glass: industrial operation and product quality

    Jacquet-Francillon, N.; Leroy, P.; Runge, S.

    1992-01-01

    This extended summary discusses the immobilization of high level wastes from the viewpoint of the quality of the final product, i.e. the HLW glass. The R and D studies comprise 3 steps: glass formulation, glass characterization and long term behaviour studies

  9. Development Of Glass Matrices For HLW Radioactive Wastes

    Jantzen, C.

    2010-01-01

    Vitrification is currently the most widely used technology for the treatment of high level radioactive wastes (HLW) throughout the world. Most of the nations that have generated HLW are immobilizing in either borosilicate glass or phosphate glass. One of the primary reasons that glass has become the most widely used immobilization media is the relative simplicity of the vitrification process, e.g. melt waste plus glass forming frit additives and cast. A second reason that glass has become widely used for HLW is that the short range order (SRO) and medium range order (MRO) found in glass atomistically bonds the radionuclides and governs the melt properties such as viscosity, resistivity, sulphate solubility. The molecular structure of glass controls contaminant/radionuclide release by establishing the distribution of ion exchange sites, hydrolysis sites, and the access of water to those sites. The molecular structure is flexible and hence accounts for the flexibility of glass formulations to waste variability. Nuclear waste glasses melt between 1050-1150 C which minimizes the volatility of radioactive components such as Tc 99 , Cs 137 , and I 129 . Nuclear waste glasses have good long term stability including irradiation resistance. Process control models based on the molecular structure of glass have been mechanistically derived and have been demonstrated to be accurate enough to control the world's largest HLW Joule heated ceramic melter in the US since 1996 at 95% confidence.

  10. DEVELOPMENT OF GLASS MATRICES FOR HLW RADIOACTIVE WASTES

    Jantzen, C.

    2010-03-18

    Vitrification is currently the most widely used technology for the treatment of high level radioactive wastes (HLW) throughout the world. Most of the nations that have generated HLW are immobilizing in either borosilicate glass or phosphate glass. One of the primary reasons that glass has become the most widely used immobilization media is the relative simplicity of the vitrification process, e.g. melt waste plus glass forming frit additives and cast. A second reason that glass has become widely used for HLW is that the short range order (SRO) and medium range order (MRO) found in glass atomistically bonds the radionuclides and governs the melt properties such as viscosity, resistivity, sulphate solubility. The molecular structure of glass controls contaminant/radionuclide release by establishing the distribution of ion exchange sites, hydrolysis sites, and the access of water to those sites. The molecular structure is flexible and hence accounts for the flexibility of glass formulations to waste variability. Nuclear waste glasses melt between 1050-1150 C which minimizes the volatility of radioactive components such as Tc{sup 99}, Cs{sup 137}, and I{sup 129}. Nuclear waste glasses have good long term stability including irradiation resistance. Process control models based on the molecular structure of glass have been mechanistically derived and have been demonstrated to be accurate enough to control the world's largest HLW Joule heated ceramic melter in the US since 1996 at 95% confidence.

  11. Comparison of the corrosion behaviors of the glass-bonded sodalite ceramic waste form and reference HLW glasses

    Ebert, W. L.; Lewis, M. A.

    1999-01-01

    A glass-bonded sodalite ceramic waste form is being developed for the long-term immobilization of salt wastes that are generated during spent nuclear fuel conditioning activities. A durable waste form is prepared by hot isostatic pressing (HIP) a mixture of salt-loaded zeolite powders and glass frit. A mechanistic description of the corrosion processes is being developed to support qualification of the CWF for disposal. The initial set of characterization tests included two standard tests that have been used extensively to study the corrosion behavior of high level waste (HLW) glasses: the Material Characterization Center-1 (MCC-1) Test and the Product Consistency Test (PCT). Direct comparison of the results of tests with the reference CWF and HLW glasses indicate that the corrosion behaviors of the CWF and HLW glasses are very similar

  12. Cooling and cracking of technical HLW glass products

    Kienzler, B.

    1989-01-01

    The author discusses various cooling procedures applied to canisters filled with inactive simulated HLW glass and the measured temperature distributions compared with numerically computed data. Stress computations of the cooling process were carried out with a finite element method. Only those volume elements having temperatures below the transformation temperature Tg were assumed to contribute thermoelastically to the developing stresses. Model calculations were extended to include real HLW glass canisters with inherent thermal power. The development of stress as a function of variations of heat flow conditions and of the radioactive decay was studied

  13. Expected behavior of HLW glass in storage

    McElroy, J.L.

    1975-01-01

    Glass produced by solidification of high-level radioactive liquid waste is studied. Conditions to which the waste form will be exposed in a typical handling sequence representative of current U. S. planning are tabulated. The reference matrix for waste form characterization is discussed, and some of the properties of high-level waste glass are described: physical properties, leachability, fracturing, vaporization, and containment in canister. 12 fig, 5 tables

  14. HIGH ALUMINUM HLW (HIGH LEVEL WASTE) GLASSES FOR HANFORD'S WTP (WASTE TREATMENT PROJECT)

    Kruger, A.A.; Bowan, B.W.; Joseph, I.; Gan, H.; Kot, W.K.; Matlack, K.S.; Pegg, I.L.

    2010-01-01

    This paper presents the results of glass formulation development and melter testing to identify high waste loading glasses to treat high-Al high level waste (HLW) at Hanford. Previous glass formulations developed for this HLW had high waste loadings but their processing rates were lower that desired. The present work was aimed at improving the glass processing rate while maintaining high waste loadings. Glass formulations were designed, prepared at crucible-scale and characterized to determine their properties relevant to processing and product quality. Glass formulations that met these requirements were screened for melt rates using small-scale tests. The small-scale melt rate screening included vertical gradient furnace (VGF) and direct feed consumption (DFC) melter tests. Based on the results of these tests, modified glass formulations were developed and selected for larger scale melter tests to determine their processing rate. Melter tests were conducted on the DuraMelter 100 (DMIOO) with a melt surface area of 0.11 m 2 and the DuraMelter 1200 (DMI200) HLW Pilot Melter with a melt surface area of 1.2 m 2 . The newly developed glass formulations had waste loadings as high as 50 wt%, with corresponding Al 2 O 3 concentration in the glass of 26.63 wt%. The new glass formulations showed glass production rates as high as 1900 kg/(m 2 .day) under nominal melter operating conditions. The demonstrated glass production rates are much higher than the current requirement of 800 kg/(m 2 .day) and anticipated future enhanced Hanford Tank Waste Treatment and Immobilization Plant (WTP) requirement of 1000 kg/(m 2 .day).

  15. MELT RATE ENHANCEMENT FOR HIGH ALUMINUM HLW (HIGH LEVEL WASTE) GLASS FORMULATION FINAL REPORT 08R1360-1

    KRUGER AA; MATLACK KS; KOT W; PEGG IL; JOSEPH I; BARDAKCI T; GAN H; GONG W; CHAUDHURI M

    2010-01-04

    This report describes the development and testing of new glass formulations for high aluminum waste streams that achieve high waste loadings while maintaining high processing rates. The testing was based on the compositions of Hanford High Level Waste (HLW) with limiting concentrations of aluminum specified by the Office of River Protection (ORP). The testing identified glass formulations that optimize waste loading and waste processing rate while meeting all processing and product quality requirements. The work included preparation and characterization of crucible melts and small scale melt rate screening tests. The results were used to select compositions for subsequent testing in a DuraMelter 100 (DM100) system. These tests were used to determine processing rates for the selected formulations as well as to examine the effects of increased glass processing temperature, and the form of aluminum in the waste simulant. Finally, one of the formulations was selected for large-scale confirmatory testing on the HLW Pilot Melter (DM1200), which is a one third scale prototype of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) HLW melter and off-gas treatment system. This work builds on previous work performed at the Vitreous State Laboratory (VSL) for Department of Energy (DOE) to increase waste loading and processing rates for high-iron HLW waste streams as well as previous tests conducted for ORP on the same high-aluminum waste composition used in the present work and other Hanford HLW compositions. The scope of this study was outlined in a Test Plan that was prepared in response to an ORP-supplied statement of work. It is currently estimated that the number of HLW canisters to be produced in the WTP is about 13,500 (equivalent to 40,500 MT glass). This estimate is based upon the inventory of the tank wastes, the anticipated performance of the sludge treatment processes, and current understanding of the capability of the borosilicate glass waste form

  16. MELT RATE ENHANCEMENT FOR HIGH ALUMINUM HLW (HIGH LEVEL WASTE) GLASS FORMULATION. FINAL REPORT 08R1360-1

    Kruger, A.A.; Matlack, K.S.; Kot, W.; Pegg, I.L.; Joseph, I.; Bardakci, T.; Gan, H.; Gong, W.; Chaudhuri, M.

    2010-01-01

    This report describes the development and testing of new glass formulations for high aluminum waste streams that achieve high waste loadings while maintaining high processing rates. The testing was based on the compositions of Hanford High Level Waste (HLW) with limiting concentrations of aluminum specified by the Office of River Protection (ORP). The testing identified glass formulations that optimize waste loading and waste processing rate while meeting all processing and product quality requirements. The work included preparation and characterization of crucible melts and small scale melt rate screening tests. The results were used to select compositions for subsequent testing in a DuraMelter 100 (DM100) system. These tests were used to determine processing rates for the selected formulations as well as to examine the effects of increased glass processing temperature, and the form of aluminum in the waste simulant. Finally, one of the formulations was selected for large-scale confirmatory testing on the HLW Pilot Melter (DM1200), which is a one third scale prototype of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) HLW melter and off-gas treatment system. This work builds on previous work performed at the Vitreous State Laboratory (VSL) for Department of Energy (DOE) to increase waste loading and processing rates for high-iron HLW waste streams as well as previous tests conducted for ORP on the same high-aluminum waste composition used in the present work and other Hanford HLW compositions. The scope of this study was outlined in a Test Plan that was prepared in response to an ORP-supplied statement of work. It is currently estimated that the number of HLW canisters to be produced in the WTP is about 13,500 (equivalent to 40,500 MT glass). This estimate is based upon the inventory of the tank wastes, the anticipated performance of the sludge treatment processes, and current understanding of the capability of the borosilicate glass waste form

  17. Chemical compatibility of HLW borosilicate glasses with actinides

    Walker, C.T.; Scheffler, K.; Riege, U.

    1978-11-01

    During liquid storage of HLLW the formation of actinide enriched sludges is being expected. Also during melting of HLW glasses an increase of top-to-bottom actinide concentrations can take place. Both effects have been studied. Besides, the vitrification of plutonium enriched wastes from Pu fuel element fabrication plants has been investigated with respect to an isolated vitrification process or a combined one with the HLLW. It is shown that the solidification of actinides from HLLW and actinide waste concentrates will set no principal problems. The leaching of actinides has been measured in salt brine at 23 0 C and 115 0 C. (orig.) [de

  18. DM100 AND DM1200 MELTER TESTING WITH HIGH WASTE LOADING GLASS FORMULATIONS FOR HANFORD HIGH-ALUMINUM HLW STREAMS

    KRUGER AA; MATLACK KS; KOT WK; PEGG IL; JOSEPH I

    2009-12-30

    This Test Plan describes work to support the development and testing of high waste loading glass formulations that achieve high glass melting rates for Hanford high aluminum high level waste (HLW). In particular, the present testing is designed to evaluate the effect of using low activity waste (LAW) waste streams as a source of sodium in place ofchemical additives, sugar or cellulose as a reductant, boehmite as an aluminum source, and further enhancements to waste processing rate while meeting all processing and product quality requirements. The work will include preparation and characterization of crucible melts in support of subsequent DuraMelter 100 (DM 100) tests designed to examine the effects of enhanced glass formulations, glass processing temperature, incorporation of the LAW waste stream as a sodium source, type of organic reductant, and feed solids content on waste processing rate and product quality. Also included is a confirmatory test on the HLW Pilot Melter (DM1200) with a composition selected from those tested on the DM100. This work builds on previous work performed at the Vitreous State Laboratory (VSL) for Department of Energy's (DOE's) Office of River Protection (ORP) to increase waste loading and processing rates for high-iron HLW waste streams as well as previous tests conducted for ORP on the same waste composition. This Test Plan is prepared in response to an ORP-supplied statement of work. It is currently estimated that the number of HLW canisters to be produced in the Hanford Tank Waste Treatment and Immobilization Plant (WTP) is about 12,500. This estimate is based upon the inventory ofthe tank wastes, the anticipated performance of the sludge treatment processes, and current understanding of the capability of the borosilicate glass waste form. The WTP HLW melter design, unlike earlier DOE melter designs, incorporates an active glass bubbler system. The bubblers create active glass pool convection and thereby improve heat

  19. Final Report - Crystal Settling, Redox, and High Temperature Properties of ORP HLW and LAW Glasses, VSL-09R1510-1, Rev. 0, dated 6/18/09

    Kruger, Albert A.; Wang, C.; Gan, H.; Pegg, I. L.; Chaudhuri, M.; Kot, W.; Feng, Z.; Viragh, C.; McKeown, D. A.; Joseph, I.; Muller, I. S.; Cecil, R.; Zhao, W.

    2013-11-13

    The radioactive tank waste treatment programs at the U. S. Department of Energy (DOE) have featured joule heated ceramic melter technology for the vitrification of high level waste (HLW). The Hanford Tank Waste Treatment and Immobilization Plant (WTP) employs this same basic technology not only for the vitrification of HLW streams but also for the vitrification of Low Activity Waste (LAW) streams. Because of the much greater throughput rates required of the WTP as compared to the vitrification facilities at the West Valley Demonstration Project (WVDP) or the Defense Waste Processing Facility (DWPF), the WTP employs advanced joule heated melters with forced mixing of the glass pool (bubblers) to improve heat and mass transport and increase melting rates. However, for both HLW and LAW treatment, the ability to increase waste loadings offers the potential to significantly reduce the amount of glass that must be produced and disposed and, therefore, the overall project costs. This report presents the results from a study to investigate several glass property issues related to WTP HLW and LAW vitrification: crystal formation and settling in selected HLW glasses; redox behavior of vanadium and chromium in selected LAW glasses; and key high temperature thermal properties of representative HLW and LAW glasses. The work was conducted according to Test Plans that were prepared for the HLW and LAW scope, respectively. One part of this work thus addresses some of the possible detrimental effects due to considerably higher crystal content in waste glass melts and, in particular, the impact of high crystal contents on the flow property of the glass melt and the settling rate of representative crystalline phases in an environment similar to that of an idling glass melter. Characterization of vanadium redox shifts in representative WTP LAW glasses is the second focal point of this work. The third part of this work focused on key high temperature thermal properties of

  20. Feasibility Study for Preparation and Use of Glass Grains as an Alternative to Glass Nodules for Vitrification of Nuclear Waste

    Sonavane, M S; Mishra, P.K., E-mail: maheshss@barc.gov.in [Nuclear Recycle Board, Bhabha Atomic Research Centre, Mumbai (India); Mandal, S; Barik, S; Roy Chowdhury, A; Sen, R [Central Glass and Ceramic Institute, Kolkata (India)

    2012-10-15

    High level nuclear liquid waste (HLW) is immobilized using borosilicate glass matrix. Presently joule heated ceramic melter is being employed for vitrification of HLW in India. Preformed nodules of base glass are fed to melter along with liquid waste in predetermined ratio. In order to reduce the cost incurred for production of glass nodules of base glass, an alternative option of using glass grains was evaluated for its preparation and its suitability for the melter operation. (author)

  1. Feasibility Study for Preparation and Use of Glass Grains as an Alternative to Glass Nodules for Vitrification of Nuclear Waste

    Sonavane, M.S.; Mishra, P.K.; Mandal, S.; Barik, S.; Roy Chowdhury, A.; Sen, R.

    2012-01-01

    High level nuclear liquid waste (HLW) is immobilized using borosilicate glass matrix. Presently joule heated ceramic melter is being employed for vitrification of HLW in India. Preformed nodules of base glass are fed to melter along with liquid waste in predetermined ratio. In order to reduce the cost incurred for production of glass nodules of base glass, an alternative option of using glass grains was evaluated for its preparation and its suitability for the melter operation. (author)

  2. Using process instrumentation to obviate destructive examination of canisters of HLW glass

    Kuhn, W.L.; Slate, S.C.

    1983-01-01

    An important concern of a manufacturer of packages of solidified high-level waste (HLW) is quality assurance of the waste form. The vitrification of HLW as a borosilicate glass is considered, and, based on a reference vitrification process, it is proposed that information from process instrumentation may be used to assure quality without the need for additional information obtained by destructive examining (core drilling) canisters of glass. This follows mainly because models of product performance and process behavior must be previously established in order to confidently select the desired glass formulation, and to have confidence that the process is well enough developed to be installed and operated in a nuclear facility

  3. The production of advanced glass ceramic HLW forms using cold crucible induction melter

    Rutledge, V.J.; Maio, V.

    2013-01-01

    Cold Crucible Induction Melters (CCIM) will favorably change how High-Level radioactive Waste (from nuclear fuel recovery) is treated in a near future. Unlike the existing Joule-Heated Melters (JHM) currently in operation for the glass-based immobilization of High-Level Waste (HLW), CCIM offers unique material features that will increase melt temperatures, increase throughput, increase mixing, increase loading in the waste form, lower melter foot prints, eliminate melter corrosion and lower costs. These features not only enhance the technology for producing HLW forms, but also provide advantageous attributes to the waste form by allowing more durable alternatives to glass. It is concluded that glass ceramic waste forms that are tailored to immobilize fission products of HLW can be can be made from the HLW processed with the CCIM. The advantageous higher temperatures reached with the CCIM and unachievable with JHM allows the lanthanides, alkali, alkaline earths, and molybdenum to dissolve into a molten glass. Upon controlled cooling they go into targeted crystalline phases to form a glass ceramic waste form with higher waste loadings than achievable with borosilicate glass waste forms. Natural cooling proves to be too fast for the formation of all targeted crystalline phases

  4. LIQUIDUS TEMPERATURE AND ONE PERCENT CRYSTAL CONTENT MODELS FOR INITIAL HANFORD HLW GLASSES

    Vienna, John D.; Edwards, Tommy B.; Crum, Jarrod V.; Kim, Dong-Sang; Peeler, David K.

    2005-01-01

    Preliminary models for liquidus temperature (TL) and temperature at 1 vol% crystal (T01) applicable to WTP HLW glasses in the spinel primary phase field were developed. A series of literature model forms were evaluated using consistent sets of data form model fitting and validation. For TL, the ion potential and linear mixture models performed best, while for T01 the linear mixture model out performed all other model forms. TL models were able to predict with smaller uncertainty. However, the lower T01 values (even with higher prediction uncertainties) were found to allow for a much broader processing envelope for WTP HLW glasses

  5. Long-term product consistency test of simulated 90-19/Nd HLW glass

    Gan, X.Y.; Zhang, Z.T.; Yuan, W.Y.; Wang, L.; Bai, Y.; Ma, H.

    2011-01-01

    Chemical durability of 90-19/Nd glass, a simulated high-level waste (HLW) glass in contact with the groundwater was investigated with a long-term product consistency test (PCT). Generally, it is difficult to observe the long term property of HLW glass due to the slow corrosion rate in a mild condition. In order to overcome this problem, increased contacting surface (S/V = 6000 m -1 ) and elevated temperature (150 o C) were employed to accelerate the glass corrosion evolution. The micro-morphological characteristics of the glass surface and the secondary minerals formed after the glass alteration were analyzed by SEM-EDS and XRD, and concentrations of elements in the leaching solution were determined by ICP-AES. In our experiments, two types of minerals, which have great impact on glass dissolution, were found to form on 90-19/Nd HLW glass surface when it was subjected to a long-term leaching in the groundwater. One is Mg-Fe-rich phyllosilicates with honeycomb structure; the other is aluminosilicates (zeolites). Mg and Fe in the leaching solution participated in the formation of phyllosilicates. The main components of phyllosilicates in alteration products of 90-19/Nd HLW glass are nontronite (Na 0.3 Fe 2 Si 4 O 10 (OH) 2 .4H 2 O) and montmorillonite (Ca 0.2 (Al,Mg) 2 Si 4 O 10 (OH) 2 .4H 2 O), and those of aluminosilicates are mordenite ((Na 2 ,K 2 ,Ca)Al 2 Si 10 O 24 .7H 2 O)) and clinoptilolite ((Na,K,Ca) 5 Al 6 Si 30 O 72 .18H 2 O). Minerals like Ca(Mg)SO 4 and CaCO 3 with low solubility limits are prone to form precipitant on the glass surface. Appearance of the phyllosilicates and aluminosilicates result in the dissolution rate of 90-19/Nd HLW glass resumed, which is increased by several times over the stable rate. As further dissolution of the glass, both B and Na in the glass were found to leach out in borax form.

  6. Studies on the long-term characteristics of HLW glass under ultimate storage conditions

    Roggendorf, H.; Conradt, R.; Ostertag, R.

    1987-01-01

    This interim report deals with first results of corrosion investigations of HLW simulation glass (COGEMA glass SON 68) in quinary salt solutions of different concentrations; the aim of these investigations was to find out about the corrosion mechanism at the surface of the glass and the quantitative registration of the corrosion products. It became obvious that the surface layers developed can be easily removed and that a determination of weight losses becomes possible thereby. The corrosion rates for a test period of 30 days were determined. (RB) [de

  7. Effect of composition on peraluminous glass properties: An application to HLW containment

    Piovesan, V.; Bardez-Giboire, I.; Perret, D.; Montouillout, V.; Pellerin, N.

    2017-01-01

    Part of the Research and Development program concerning high level nuclear waste (HLW) glasses aims to assess new glass formulations able to incorporate a high waste content with enhanced properties in terms of thermal stability, chemical durability, and process ability. This study focuses on peraluminous glasses of the SiO2 - Al2O3 - B2O3 - Na2O - Li2O - CaO - La2O3 system, defined by an excess of aluminum ions Al3+ in comparison with modifier elements such as Na+, Li+ or Ca2+. To understand the effect of composition on physical properties of glasses (viscosity, density, Tg), a Design Of Experiments (DOE) approach was applied to investigate the peraluminous glass domain. The influence of each oxide was quantified to build predictive models for each property. Lanthanum and lithium oxides appear to be the most influential factors on peraluminous glass properties.

  8. Enhanced HLW glass formulations for the waste treatment and immobilization plant

    Kruger, Albert A. [DOE-WTP Project Office, US Department of Energy, Richland, Washington (United States)

    2013-07-01

    Current estimates and glass formulation efforts are conservative vis-a-vis achievable waste loadings. These formulations have been specified to ensure that glasses are homogenous, contain essentially no crystalline phases, are processable in joule-heated, ceramic-lined melters and meet WTP Contract terms. The WTP's overall mission will require the immobilization of tank waste compositions that are dominated by mixtures of aluminum, chromium, bismuth, iron, phosphorous, zirconium, and sulfur compounds as waste-limiting components. Glass compositions for these waste mixtures have been developed based upon previous experience and current glass property models. DOE has a testing program to develop and characterize HLW glasses with higher waste loadings. This work has demonstrated the feasibility of increases in waste loading from 25 wt% to 33-50 wt% (based on oxide loading) in the glass depending on the waste stream. It is expected these higher waste loading glasses will reduce the HLW canister production requirement by 25% or more. (authors)

  9. Corrosion behaviour of the WAK-HLW glass

    Grambow, B.; Luckscheiter, B.; Nesovic, M.

    1997-01-01

    Sorption studies were performed on corrosion products from the glass GP WAK1 formed over a period of 40 days in deionized water at 80 C and S/V=1000 m -1 . After 40 days the pH of the solution was adjusted to various preselected values in the pH range 2-10. The pH was kept constant during the experiments by daily addition of either HNO 3 or NaOH. The sorption experiments were run at ambient temperature and 80 C for up to 10 days using various starting concentrations of Eu, Th and U. Sorption isotherms of Eu, Th and U(VI) on corrosion products were determined in deionized water, in NaCl-rich and MgCl 2 -rich solution. Presently, data of the sorption studies in deionized water are available.Furthermore the investigations of the pH dependence of saturation concentration of silica and of the release of various glass constituent of the glass GP WAK1 were continued with studies in the MgCl 2 -rich solution 1 at 80 C. Results of these studies (30 days) are given in terms of normalized elemental mass losses. (MM)

  10. HLW vitrification in France industrial experience and glass quality

    Desvaux, J.L.; Delahaye, P.

    1994-01-01

    This paper describes the vitrification process, the technology and process improvements at the La Hague plant in R 7 and T 7 facilities. The main achievements relate to the process flexibility, the reliability of the equipment and solid waste management. The quality of the vitrified glass produced and canisters compliance with agreed specifications are demonstrated through characterization studies. Since the active start-up of R 7/T 7 facilities, canisters compliance with specifications relies upon a complete quality assurance/quality control program including process control. 1 tab., 1 fig

  11. Determination of alpha dose rate profile at the HLW nuclear glass/water interface

    Mougnaud, S., E-mail: sarah.mougnaud@cea.fr [CEA Marcoule, DEN/DTCD/SECM, BP 17171, 30207 Bagnols-sur-Cèze cedex (France); Tribet, M.; Rolland, S. [CEA Marcoule, DEN/DTCD/SECM, BP 17171, 30207 Bagnols-sur-Cèze cedex (France); Renault, J.-P. [CEA Saclay, NIMBE UMR 3685 CEA/CNRS, 91191 Gif-sur-Yvette cedex (France); Jégou, C. [CEA Marcoule, DEN/DTCD/SECM, BP 17171, 30207 Bagnols-sur-Cèze cedex (France)

    2015-07-15

    Highlights: • The nuclear glass/water interface is studied. • The way the energy of alpha particles is deposited is modeled using MCNPX code. • A model giving dose rate profiles at the interface using intrinsic data is proposed. • Bulk dose rate is a majoring estimation in alteration layer and in surrounding water. • Dose rate is high in small cracks; in larger ones irradiated volume is negligible. - Abstract: Alpha irradiation and radiolysis can affect the alteration behavior of High Level Waste (HLW) nuclear glasses. In this study, the way the energy of alpha particles, emitted by a typical HLW glass, is deposited in water at the glass/water interface is investigated, with the aim of better characterizing the dose deposition at the glass/water interface during water-induced leaching mechanisms. A simplified chemical composition was considered for the nuclear glass under study, wherein the dose rate is about 140 Gy/h. The MCNPX calculation code was used to calculate alpha dose rate and alpha particle flux profiles at the glass/water interface in different systems: a single glass grain in water, a glass powder in water and a water-filled ideal crack in a glass package. Dose rate decreases within glass and in water as distance to the center of the grain increases. A general model has been proposed to fit a dose rate profile in water and in glass from values for dose rate in glass bulk, alpha range in water and linear energy transfer considerations. The glass powder simulation showed that there was systematic overlapping of radiation fields for neighboring glass grains, but the water dose rate always remained lower than the bulk value. Finally, for typical ideal cracks in a glass matrix, an overlapping of irradiation fields was observed while the crack aperture was lower than twice the alpha range in water. This led to significant values for the alpha dose rate within the crack volume, as long as the aperture remained lower than 60 μm.

  12. The Production of Advanced Glass Ceramic HLW Forms using Cold Crucible Induction Melter

    Veronica J Rutledge; Vince Maio

    2013-10-01

    Cold Crucible Induction Melters (CCIMs) will favorably change how High-Level radioactive Waste (from nuclear fuel recovery) is treated in the 21st century. Unlike the existing Joule-Heated Melters (JHMs) currently in operation for the glass-based immobilization of High-Level Waste (HLW), CCIMs offer unique material features that will increase melt temperatures, increase throughput, increase mixing, increase loading in the waste form, lower melter foot prints, eliminate melter corrosion and lower costs. These features not only enhance the technology for producing HLW forms, but also provide advantageous attributes to the waste form by allowing more durable alternatives to glass. This paper discusses advantageous features of the CCIM, with emphasis on features that overcome the historical issues with the JHMs presently utilized, as well as the benefits of glass ceramic waste forms over borosilicate glass waste forms. These advantages are then validated based on recent INL testing to demonstrate a first-of-a-kind formulation of a non-radioactive ceramic-based waste form utilizing a CCIM.

  13. Effect of composition on peraluminous glass properties: An application to HLW containment

    Piovesan, V. [CEA, DEN, DTCD, SECM, LDMC – Marcoule, F-30207 Bagnols sur Cèze (France); CNRS, CEMHTI UPR3079, Univ. Orléans, F-45071 Orléans (France); Bardez-Giboire, I., E-mail: isabelle.giboire@cea.fr [CEA, DEN, DTCD, SECM, LDMC – Marcoule, F-30207 Bagnols sur Cèze (France); Perret, D. [CEA, DEN, DTCD, SECM, LDMC – Marcoule, F-30207 Bagnols sur Cèze (France); Montouillout, V.; Pellerin, N. [CNRS, CEMHTI UPR3079, Univ. Orléans, F-45071 Orléans (France)

    2017-01-15

    Part of the Research and Development program concerning high level nuclear waste (HLW) glasses aims to assess new glass formulations able to incorporate a high waste content with enhanced properties in terms of thermal stability, chemical durability, and process ability. This study focuses on peraluminous glasses of the SiO{sub 2} – Al{sub 2}O{sub 3} – B{sub 2}O{sub 3} – Na{sub 2}O – Li{sub 2}O – CaO – La{sub 2}O{sub 3} system, defined by an excess of aluminum ions Al{sup 3+} in comparison with modifier elements such as Na{sup +}, Li{sup +} or Ca{sup 2+}. To understand the effect of composition on physical properties of glasses (viscosity, density, T{sub g}), a Design Of Experiments (DOE) approach was applied to investigate the peraluminous glass domain. The influence of each oxide was quantified to build predictive models for each property. Lanthanum and lithium oxides appear to be the most influential factors on peraluminous glass properties. - Highlights: • A Design of Experiment approach to link composition and glass properties. • Adding alkali decreases glass transition temperature. • Adding La{sub 2}O{sub 3} strongly decreases glass melt viscosity. • Adding La{sub 2}O{sub 3} increases density.

  14. Viability for controlling long-term leaching of radionuclides from HLW glass by amorphous silica additives

    Inagaki, Y.; Uehara, S.

    2004-01-01

    Dissolution and deterioration experiments in coexistence system of amorphous silica and vitrified wastes have been executed in order to evaluating the effects of amorphous silica addition to high level radioactive vitrified waste (HLW glass) on suppression of nuclide leaching. Geo-chemical reaction mechanism among the vitrified waste, the amorphous silica and water was also evaluated. Dissolution of the silica network was suppressed by addition of the amorphous silica. However, the leaching of soluble nuclides like B proceeded depending on the hydration deterioration reaction. (A. Hishinuma)

  15. The development of basic glass formulations for solidifying HLW from nuclear fuel reprocessing plant

    Jiang Yaozhong; Tang Baolong; Zhang Baoshan; Zhou Hui

    1995-01-01

    Basic glass formulations 90U/19, 90U/20, 90Nd/7 and 90Nd/10 applied in electric melting process are developed by using the mathematical model of the viscosity and electric resistance of waste glass. The yellow phase does not occur for basic glass formulations 90U/19 and 90U/20 solidifying HLW from nuclear fuel reprocessing plant when the waste loading is 20%. Under the waste loading is 16%, the process and product properties of glass 90U/19 and 90U/20 come up to or surpass the properties of the same kind of foreign waste glasses, and other properties are about the same to them of foreign waste glasses. The process and product properties of basic glass formulations 90Nd/7 and 90Nd/10 used for the solidification of 'U replaced by Nd' liquid waste are almost similar to them of 90U/19 and 90U/20. These properties fairly meet the requirements of 'joint test' (performed at KfK-INE, Germany). Among these formulations, 90Nd/7 is applied in cold engineering scale electric melting test performed at KfK-INE in Germany. The main process properties of cold test is similar to laboratory results

  16. DATA SUMMARY REPORT SMALL SCALE MELTER TESTING OF HLW ALGORITHM GLASSES MATRIX1 TESTS VSL-07S1220-1 REV 0 7/25/07

    KRUGER AA; MATLACK KS; PEGG IL

    2011-12-29

    Eight tests using different HLW feeds were conducted on the DM100-BL to determine the effect of variations in glass properties and feed composition on processing rates and melter conditions (off-gas characteristics, glass processing, foaming, cold cap, etc.) at constant bubbling rate. In over seven hundred hours of testing, the property extremes of glass viscosity, electrical conductivity, and T{sub 1%}, as well as minimum and maximum concentrations of several major and minor glass components were evaluated using glass compositions that have been tested previously at the crucible scale. Other parameters evaluated with respect to glass processing properties were +/-15% batching errors in the addition of glass forming chemicals (GFCs) to the feed, and variation in the sources of boron and sodium used in the GFCs. Tests evaluating batching errors and GFC source employed variations on the HLW98-86 formulation (a glass composition formulated for HLW C-106/AY-102 waste and processed in several previous melter tests) in order to best isolate the effect of each test variable. These tests are outlined in a Test Plan that was prepared in response to the Test Specification for this work. The present report provides summary level data for all of the tests in the first test matrix (Matrix 1) in the Test Plan. Summary results from the remaining tests, investigating minimum and maximum concentrations of major and minor glass components employing variations on the HLW98-86 formulation and glasses generated by the HLW glass formulation algorithm, will be reported separately after those tests are completed. The test data summarized herein include glass production rates, the type and amount of feed used, a variety of measured melter parameters including temperatures and electrode power, feed sample analysis, measured glass properties, and gaseous emissions rates. More detailed information and analysis from the melter tests with complete emission chemistry, glass durability, and

  17. DETERMINATION OF HLW GLASS MELT RATE USING X-RAY COMPUTED TOMOGRAPHY

    Choi, A.; Miller, D.; Immel, D.

    2011-10-06

    The purpose of the high-level waste (HLW) glass melt rate study is two-fold: (1) to gain a better understanding of the impact of feed chemistry on melt rate through bench-scale testing, and (2) to develop a predictive tool for melt rate in support of the on-going frit development efforts for the Defense Waste Processing Facility (DWPF). In particular, the focus is on predicting relative melt rates, not the absolute melt rates, of various HLW glass formulations solely based on feed chemistry, i.e., the chemistry of both waste and glass-forming frit for DWPF. Critical to the successful melt rate modeling is the accurate determination of the melting rates of various HLW glass formulations. The baseline procedure being used at the Savannah River National Laboratory (SRNL) is to; (1) heat a 4 inch-diameter stainless steel beaker containing a mixture of dried sludge and frit in a furnace for a preset period of time, (2) section the cooled beaker along its diameter, and (3) measure the average glass height across the sectioned face using a ruler. As illustrated in Figure 1-1, the glass height is measured for each of the 16 horizontal segments up to the red lines where relatively large-sized bubbles begin to appear. The linear melt rate (LMR) is determined as the average of all 16 glass height readings divided by the time during which the sample was kept in the furnace. This 'visual' method has proved useful in identifying melting accelerants such as alkalis and sulfate and further ranking the relative melt rates of candidate frits for a given sludge batch. However, one of the inherent technical difficulties of this method is to determine the glass height in the presence of numerous gas bubbles of varying sizes, which is prevalent especially for the higher-waste-loading glasses. That is, how the red lines are drawn in Figure 1-1 can be subjective and, therefore, may influence the resulting melt rates significantly. For example, if the red lines are drawn too low

  18. Crystallization in high level waste (HLW) glass melters: Savannah River Site operational experience

    Fox, Kevin M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Peeler, David K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Kruger, Albert A. [USDOE Office of River Protection, Richland, WA (United States)

    2015-06-12

    This paper provides a review of the scaled melter testing that was completed for design input to the Defense Waste Processing Facility (DWPF) melter. Testing with prototype melters provided the data to define the DWPF operating limits to avoid bulk (volume) crystallization in the un-agitated DWPF melter and provided the data to distinguish between spinels generated by refractory corrosion versus spinels that precipitated from the HLW glass melt pool. A review of the crystallization observed with the prototype melters and the full-scale DWPF melters (DWPF Melter 1 and DWPF Melter 2) is included. Examples of actual DWPF melter attainment with Melter 2 are given. The intent is to provide an overview of lessons learned, including some example data, that can be used to advance the development and implementation of an empirical model and operating limit for crystal accumulation for a waste treatment and immobilization plant.

  19. Impact Of Particle Agglomeration On Accumulation Rates In The Glass Discharge Riser Of HLW Melter

    Kruger, A. A.; Rodriguez, C. A.; Matyas, J.; Owen, A. T.; Jansik, D. P.; Lang, J. B.

    2012-01-01

    The major factor limiting waste loading in continuous high-level radioactive waste (HLW) melters is an accumulation of particles in the glass discharge riser during a frequent and periodic idling of more than 20 days. An excessive accumulation can produce robust layers a few centimeters thick, which may clog the riser, preventing molten glass from being poured into canisters. Since the accumulation rate is driven by the size of particles we investigated with x-ray microtomography, scanning electron microscopy, and image analysis the impact of spinel forming components, noble metals, and alumina on the size, concentration, and spatial distribution of particles, and on the accumulation rate. Increased concentrations of Fe and Ni in the baseline glass resulted in the formation of large agglomerates that grew over the time to an average size of ∼185+-155 μm, and produced >3 mm thick layer after 120 h at 850 deg C. The noble metals decreased the particle size, and therefore significantly slowed down the accumulation rate. Addition of alumina resulted in the formation of a network of spinel dendrites which prevented accumulation of particles into compact layers

  20. TESTS WITH HIGH-BISMUTH HLW GLASSES FINAL REPORT VSL-10R1780-1, Rev. 0; 12/13/10

    Matlack, K.S.; Kruger, A.A.; Joseph, I.; Gan, H.; Kot, W.K.; Chaudhuri, M.; Mohr, R.K.; Mckeown, D.A.; Bardakei, T.; Gong, W.; Buecchele, A.C.; Pegg, I.L.

    2011-01-01

    This Final Report describes the testing of glass formulations developed for Hanford High Level Waste (HLW) containing high concentrations of bismuth. In previous work on high-bismuth HLW streams specified by the Office of River Protection (ORP), fully compliant, high waste loading compositions were developed and subjected to melter testing on the DM100 vitrification system. However, during heat treatment according to the Hanford Tank Waste Treatment and Immobilization Plant (WTP) HLW canister centerline cooling (CCC) curves, crucible melts of the high-bismuth glasses were observed to foam. Clearly, such an occurrence during cooling of actual HLW canisters would be highly undesirable. Accordingly, the present work involves larger-scale testing to determine whether this effect occurs under more prototypical conditions, as well as crucible-scale tests to determine the causes and potentially remediate the observed foaming behavior. The work included preparation and characterization of crucible melts designed to determine the underlying causes of the foaming behavior as well as to assess potential mitigation strategies. Testing was also conducted on the DM1200 HLW Pilot melter with a composition previously tested on the DM100 and shown to foam during crucible-scale CCC heat treatment. The DM1200 tests evaluated foaming of glasses over a range of bismuth concentrations poured into temperature-controlled, 55-gallon drums which have a diameter that is close to that of the full-scale WTP HLW canisters. In addition, the DM1200 tests provided the first large-scale melter test data on high-bismuth WTP HLW compositions, including information on processing rates, cold cap behavior and off-gas characteristics, and data from this waste composition on the prototypical DM1200 off-gas treatment system. This work builds on previous work performed at the Vitreous State Laboratory (VSL) for ORP on the same waste composition. The scope of this study was outlined in a Test Plan that was

  1. TESTS WITH HIGH-BISMUTH HLW GLASSES FINAL REPORT VSL-10R1780-1 REV 0 12/13/10

    MATLACK KS; KRUGER AA; JOSEPH I; GAN H; KOT WK; CHAUDHURI M; MOHR RK; MCKEOWN DA; BARDAKEI T; GONG W; BUECCHELE AC; PEGG IL

    2011-01-05

    This Final Report describes the testing of glass formulations developed for Hanford High Level Waste (HLW) containing high concentrations of bismuth. In previous work on high-bismuth HLW streams specified by the Office of River Protection (ORP), fully compliant, high waste loading compositions were developed and subjected to melter testing on the DM100 vitrification system. However, during heat treatment according to the Hanford Tank Waste Treatment and Immobilization Plant (WTP) HLW canister centerline cooling (CCC) curves, crucible melts of the high-bismuth glasses were observed to foam. Clearly, such an occurrence during cooling of actual HLW canisters would be highly undesirable. Accordingly, the present work involves larger-scale testing to determine whether this effect occurs under more prototypical conditions, as well as crucible-scale tests to determine the causes and potentially remediate the observed foaming behavior. The work included preparation and characterization of crucible melts designed to determine the underlying causes of the foaming behavior as well as to assess potential mitigation strategies. Testing was also conducted on the DM1200 HLW Pilot melter with a composition previously tested on the DM100 and shown to foam during crucible-scale CCC heat treatment. The DM1200 tests evaluated foaming of glasses over a range of bismuth concentrations poured into temperature-controlled, 55-gallon drums which have a diameter that is close to that of the full-scale WTP HLW canisters. In addition, the DM1200 tests provided the first large-scale melter test data on high-bismuth WTP HLW compositions, including information on processing rates, cold cap behavior and off-gas characteristics, and data from this waste composition on the prototypical DM1200 off-gas treatment system. This work builds on previous work performed at the Vitreous State Laboratory (VSL) for ORP on the same waste composition. The scope of this study was outlined in a Test Plan that was

  2. Long term corrosion behavior of the WAK-HLW glass in salt solutions

    Luckscheiter, B.; Nesovic, M.

    1998-01-01

    The corrosion behavior of the HLW glass GP WAK1 containing simulated HLW oxides from the WAK reprocessing plant in Karlsruhe is investigated in long-term corrosion experiments at high S/V ratios in two reference brines at 110 and 190 C. In case of the MgCl 2 -rich solution the leachate becomes increasingly acid with reaction time up to a final pH of about 3.5 at 190 C. In the NaCl-rich solution the pH rises to about 8.5 after one year of reaction. The release of soluble elements in MgCl 2 solution, under Si-saturated conditions, is proportional to the surface area of the sample and the release increases at 190 C according to a t 1/2 rate law. This time dependence may be an indication of diffusion controlled matrix dissolution. However, at 110 C the release of the mobile elements cannot be described by a t 1/2 rate law as the time exponents are much lower than 0.5. This difference in corrosion behavior may be explained by the higher pH of about 5 at 110 C. In case of NaCl solution under alkaline conditions, the release of soluble elements is not proportional to the surface area of the sample and it increases with time exponents much lower than 0.5. After one year of reaction at 190 C a sharp increase of the release values of some elements was observed. This increase might be explained by the high pH of the solution attained after one year. The corrosion mechanism in NaCl solution, as well as in MgCl 2 solution at 110 C, has not yet been explained. By corrosion experiments in water at constant pH values between 2 and 10, it could be shown that the time exponents of the release of Li and B decrease with increasing pH of the solution. This result can explain qualitatively the differences found in the corrosion behavior of the glass under the various conditions

  3. Crystallization In High Level Waste (HLW) Glass Melters: Operational Experience From The Savannah River Site

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2014-02-27

    processing strategy for the Hanford Tank Waste Treatment and Immobilization Plant (WTP). The basis of this alternative approach is an empirical model predicting the crystal accumulation in the WTP glass discharge riser and melter bottom as a function of glass composition, time, and temperature. When coupled with an associated operating limit (e.g., the maximum tolerable thickness of an accumulated layer of crystals), this model could then be integrated into the process control algorithms to formulate crystal tolerant high level waste (HLW) glasses targeting higher waste loadings while still meeting process related limits and melter lifetime expectancies. This report provides a review of the scaled melter testing that was completed in support of the Defense Waste Processing Facility (DWPF) melter. Testing with scaled melters provided the data to define the DWPF operating limits to avoid bulk (volume) crystallization in the un-agitated DWPF melter and provided the data to distinguish between spinels generated by K-3 refractory corrosion versus spinels that precipitated from the HLW glass melt pool. This report includes a review of the crystallization observed with the scaled melters and the full scale DWPF melters (DWPF Melter 1 and DWPF Melter 2). Examples of actual DWPF melter attainment with Melter 2 are given. The intent is to provide an overview of lessons learned, including some example data, that can be used to advance the development and implementation of an empirical model and operating limit for crystal accumulation for WTP. Operation of the first and second (current) DWPF melters has demonstrated that the strategy of using a liquidus temperature predictive model combined with a 100 °C offset from the normal melter operating temperature of 1150 °C (i.e., the predicted liquidus temperature (TL) of the glass must be 1050 °C or less) has been successful in preventing any detrimental accumulation of spinel in the DWPF melt pool, and spinel has not been

  4. Glass formulation development and testing for the vitrification of DWPF HLW sludge coupled with crystalline silicotitanate (CST)

    Andrews, M.K.; Workman, P.J.

    1997-01-01

    An alternative to the In Tank Precipitation and sodium titanate processes at the Savannah River Site is the removal of cesium, strontium, and plutonium from the tank supernate by ion exchange using crystalline silicotitanate (CST). This inorganic material has been shown to effectively and selectively sorb these elements from supernate. The loaded CST could then be immobilized with High-Level Waste (HLW) sludge during vitrification. Initial efforts on the development of a glass formulation for a coupled waste stream indicate that reasonable loadings of both sludge and CST can be achieved in glass

  5. Final Report - Melt Rate Enhancement for High Aluminum HLW Glass Formulation, VSL-08R1360-1, Rev. 0, dated 12/19/08

    Kruger, Albert A.; Pegg, I. L.; Chaudhuri, M.; Gong, W.; Gan, H.; Matlack, K. S.; Bardakci, T.; Kot, W.

    2013-11-13

    The principal objective of the work reported here was to develop and identify HLW glass compositions that maximize waste processing rates for the aluminum limted waste composition specified by ORP while maintaining high waste loadings and acceptable glass properties. This was accomplished through a combination of crucible-scale tests, confirmation tests on the DM100 melter system, and demonstration at pilot scale (DM1200). The DM100-BL unit was selected for these tests since it was used previously with the HLW waste streams evaluated in this study, was used for tests on HLW glass compositions to support subsequent tests on the HLW Pilot Melter, conduct tests to determine the effect of various glass properties (viscosity and conductivity) and oxide concentrations on glass production rates with HLW feed streams, and to assess the volatility of cesium and technetium during the vitrification of an HLW AZ-102 composition. The same melter was selected for the present tests in order to maintain comparisons between the previously collected data. These tests provide information on melter processing characteristics and off-gas data, including formation of secondary phases and partitioning. Once DM100 tests were completed, one of the compositions was selected for further testing on the DM1200; the DM1200 system has been used for processing a variety of simulated Hanford waste streams. Tests on the larger melter provide processing data at one third of the scale of the actual WTP HLW melter and, therefore, provide a more accurate and reliable assessment of production rates and potential processing issues. The work focused on maximizing waste processing rates for high aluminum HLW compositions. In view of the diversity of forms of aluminum in the Hanford tanks, tests were also conducted on the DM100 to determine the effect of changes in the form of aluminum on feed properties and production rate. In addition, the work evaluated the effect on production rate of modest increases

  6. Advances in Glass Formulations for Hanford High-Alumimum, High-Iron and Enhanced Sulphate Management in HLW Streams-13000

    Kruger, Albert A.

    2013-01-01

    The current estimates and glass formulation efforts have been conservative in terms of achievable waste loadings. These formulations have been specified to ensure that the glasses are homogenous, contain essentially no crystalline phases, are processable in joule-heated, ceramic-lined melters and meet Hanford Tank Waste Treatment and Immobilization Plant (WTP) Contract terms. The WTP's overall mission will require the immobilization of tank waste compositions that are dominated by mixtures of aluminum (Al), chromium (Cr), bismuth (Bi), iron (Fe), phosphorous (P), zirconium (Zr), and sulphur (S) compounds as waste-limiting components. Glass compositions for these waste mixtures have been developed based upon previous experience and current glass property models. Recently, DOE has initiated a testing program to develop and characterize HLW glasses with higher waste loadings and higher throughput efficiencies. Results of this work have demonstrated the feasibility of increases in waste loading from about 25 wt% to 33-50 wt% (based on oxide loading) in the glass depending on the waste stream. In view of the importance of aluminum limited waste streams at Hanford (and also Savannah River), the ability to achieve high waste loadings without adversely impacting melt rates has the potential for enormous cost savings from reductions in canister count and the potential for schedule acceleration. Consequently, the potential return on the investment made in the development of these enhancements is extremely favorable. Glass composition development for one of the latest Hanford HLW projected compositions with sulphate concentrations high enough to limit waste loading have been successfully tested and show tolerance for previously unreported tolerance for sulphate. Though a significant increase in waste loading for high-iron wastes has been achieved, the magnitude of the increase is not as substantial as those achieved for high-aluminum, high-chromium, high-bismuth or sulphur

  7. Development Of High Waste-Loading HLW Glasses For High Bismuth Phosphate Wastes, VSL-12R2550-1, Rev 0

    Kruger, A. A.; Pegg, Ian L.; Gan, Hao; Kot, Wing K.

    2012-01-01

    This report presents results from tests with new glass formulations that have been developed for several high Bi-P HLW compositions that are expected to be processed at the WTP that have not been tested previously. WTP HLW feed compositions were reviewed to select waste batches that are high in Bi-P and that are reasonably distinct from the Bi-limited waste that has been tested previously. Three such high Bi-P HLW compositions were selected for this work. The focus of the present work was to determine whether the same type of issues as seen in previous work with high-Bi HLW will be seen in HLW with different concentrations of Bi, P and Cr and also whether similar glass formulation development approaches would be successful in mitigating these issues. New glass compositions were developed for each of the three representative Bi-P HLW wastes and characterized with respect to key processing and product quality properties and, in particular, those relating to crystallization and foaming tendency

  8. Development Of High Waste-Loading HLW Glasses For High Bismuth Phosphate Wastes, VSL-12R2550-1, Rev 0

    Kruger, A. A. [Department of Energy, Office of River Protection, Richland, Washington (United States); Pegg, Ian L. [The Catholic University of America, Washington, DC (United States); Gan, Hao [The Catholic University of America, Washington, DC (United States); Kot, Wing K. [The Catholic University of America, Washington, DC (United States)

    2012-12-13

    This report presents results from tests with new glass formulations that have been developed for several high Bi-P HLW compositions that are expected to be processed at the WTP that have not been tested previously. WTP HLW feed compositions were reviewed to select waste batches that are high in Bi-P and that are reasonably distinct from the Bi-limited waste that has been tested previously. Three such high Bi-P HLW compositions were selected for this work. The focus of the present work was to determine whether the same type of issues as seen in previous work with high-Bi HLW will be seen in HLW with different concentrations of Bi, P and Cr and also whether similar glass formulation development approaches would be successful in mitigating these issues. New glass compositions were developed for each of the three representative Bi-P HLW wastes and characterized with respect to key processing and product quality properties and, in particular, those relating to crystallization and foaming tendency.

  9. Current status of preparing buffer/backfill block in HLW disposal abroad

    Yan Ming; Wang Xuewen; Zhang Huyuan

    2014-01-01

    There is an urgent need for China to commence the full-scale compaction test, resolving the preparation problem for buffer/backfill blocks when underground research laboratory project is planned for High Level Radioactive Waste (HLW) disposal. The foreign countries have some research about the preparation of buffer/backfill blocks in engineered barrier systems. The foreign research shows that installation of clay blocks with sector shape at waste pollution area is a feasible engineering method. Compacted clay blocks need to be cured in a cabinet with controlled temperature and humidity to avoid desiccation and surface powdering. A freeze mixing method, mixing powdered-ice and cooled bentonite, can be operated more easily and obtain more uniform hydration than the traditional mixing of water and bentonite. It is helpful to review and adsorb the foreign research results for the design of full-scale test of bentonite compaction. (authors)

  10. Advances in Glass Formulations for Hanford High-Aluminum, High-Iron and Enhanced Sulphate Management in HLW Streams - 13000

    Kruger, Albert A. [WTP Engineering Division, United States Department of Energy, Office of River Protection, Post Office Box 450, Richland, Washington 99352 (United States)

    2013-07-01

    The current estimates and glass formulation efforts have been conservative in terms of achievable waste loadings. These formulations have been specified to ensure that the glasses are homogenous, contain essentially no crystalline phases, are processable in joule-heated, ceramic-lined melters and meet Hanford Tank Waste Treatment and Immobilization Plant (WTP) Contract terms. The WTP's overall mission will require the immobilization of tank waste compositions that are dominated by mixtures of aluminum (Al), chromium (Cr), bismuth (Bi), iron (Fe), phosphorous (P), zirconium (Zr), and sulphur (S) compounds as waste-limiting components. Glass compositions for these waste mixtures have been developed based upon previous experience and current glass property models. Recently, DOE has initiated a testing program to develop and characterize HLW glasses with higher waste loadings and higher throughput efficiencies. Results of this work have demonstrated the feasibility of increases in waste loading from about 25 wt% to 33-50 wt% (based on oxide loading) in the glass depending on the waste stream. In view of the importance of aluminum limited waste streams at Hanford (and also Savannah River), the ability to achieve high waste loadings without adversely impacting melt rates has the potential for enormous cost savings from reductions in canister count and the potential for schedule acceleration. Consequently, the potential return on the investment made in the development of these enhancements is extremely favorable. Glass composition development for one of the latest Hanford HLW projected compositions with sulphate concentrations high enough to limit waste loading have been successfully tested and show tolerance for previously unreported tolerance for sulphate. Though a significant increase in waste loading for high-iron wastes has been achieved, the magnitude of the increase is not as substantial as those achieved for high-aluminum, high-chromium, high-bismuth or

  11. Performance of a buried radioactive high level waste (HLW) glass after 24 years

    Jantzen, Carol M.; Kaplan, Daniel I.; Bibler, Ned E.; Peeler, David K.; John Plodinec, M.

    2008-01-01

    A radioactive high level waste glass was made in 1980 with Savannah River Site (SRS) Tank 15 waste. This glass was buried in a lysimeter in the SRS burial ground for 24 years. Lysimeter leachate data was available for the first 8 years. The glass was exhumed in 2004. The glass was predicted to be very durable and laboratory tests confirmed this. Scanning electron microscopy of the glass burial surface showed no significant glass alteration consistent with results of other laboratory and field tests. Radionuclide profiling for alpha, beta, and 137 Cs indicated that Pu was not enriched in the soil while 137 Cs and 9 deg. C Sr were enriched in the first few centimeters surrounding the glass. Lysimeter leachate data indicated that 9 deg. C Sr and 137 Cs leaching from the glass was diffusion controlled

  12. JSS project phase 4: Experimental and modelling studies of HLW glass dissolution in repository environments

    1987-10-01

    A goal of the JSS project was to develop a scientific basis for understanding the effects of waste package components, groundwater chemistry, and other repository conditions on glass dissolution behaviour, and to develop and refine a model for the processes governing glass dissolution. The fourth phase of the project, which was performed by the Hahn-Meitner-Institut, Berlin, FRG, dealt specifically with model development and application. Phase 4 also adressed whether basaltic glasses could serve as natural analogues for nuclear waste glasses, thus providing a means to test the capability of the model for long-term predictions. Additional experiments were performed in order to complete the data base necessary to model interactions between the glass and bentonite and between glass and steel corrosion products. More data on temperature, S/V, and pH dependence of the glass/water reaction were also collected. In this report, the data acquired during phase 4 are presented and discussed. (orig./DG)

  13. Final Report - Glass Formulation Development and Testing for DWPF High AI2O3 HLW Sludges, VSL-10R1670-1, Rev. 0, dated 12/20/10

    Kruger, Albert A.; Pegg, I. L.; Kot, W. K.; Gan, H.; Matlack, K. S.

    2013-11-13

    -hydroxide methods. The above tests were proposed based on previous tests for WTP in which there were few differences in the melter processing characteristics, such as processing rate and melter emissions, between precipitated and direct hydroxide simulants, even though there were differences in rheological properties. To the extent this similarity is found also for simulants for SRS HLW, the direct hydroxide methods may offer the potential for faster, simpler, and cheaper simulant production. There was no plan to match the yield stress and particle size of the direct hydroxide simulant to that of the precipitated simulant because that would have increased the preparation cost and complexity and defeated the purpose of the tests. These objectives were addressed by first developing a series of glass frits and then conducting a crucible scale study to determine the waste loading achievable for the waste composition and to select the preferred frit. Waste loadings were increased until the limits of a glass property were exceeded experimentally. Glass properties for evaluation included: viscosity, electrical conductivity, crystallinity (including liquidus temperature and nepheline formation after canister centerline cooling (CCC) heat-treatment), gross glass phase separation, and the 7- day Product Consistency Test (PCT, ASTM-1285) response. Glass property limits were based upon the constraints used for DWPF process control.

  14. In situ corrosion tests on HLW glass as part of a larger approach

    Van Iseghem, P.

    1997-01-01

    In-situ corrosion tests were performed on various candidate high-level waste glasses in the underground laboratory in clay underneath SCK x CEN. The tests exposed the glass samples directly to the Boom clay rock, for maximum durations of 7.5 years. We succeeded to interpret the corrosion data at 90 deg C in terms of dissolution mechanisms, and we concluded that the glass composition has a determining effect on the corrosion stability. The data from our in-situ tests were of high relevance for estimating the long-term behaviour of the glasses. The long-term in-situ tests provide corrosion data which show different trends than other corrosion tests, e.g. shorter duration tests in Boom clay, or tests in deionized water. The initial dissolution rate using MCC1 test at 90 deg C is about the same for the three glasses discussed, but the longest duration in Boom clay at 90 deg C shows a difference in mass loss of about 25 times. We finally present some ideas on how the corrosion tests can meet the needs, such as the modelling of the glass corrosion or providing input in the performance assessment. (author)

  15. Economic comparison of crystalline ceramic and glass waste forms for HLW disposal

    McKee, R.W.; Daling, P.M.; Wiles, L.E.

    1983-05-01

    A titanate-based, crystalline ceramic produced by hot isostatic pressing has been proposed as a potentially more stable and improved waste form for high-level nuclear waste disposal compared to the currently favored borosilicate glass waste form. This paper describes the results of a study to evaluate the relative costs for disposal of high-level waste from a 70,000 metric ton equivalent (MTE) system. The entire waste management system, including waste processing and encapsulation, transportation, and final repository disposal, was included in this analysis. The repository concept is based on the current basalt waste isolation project (BWIP) reference design. A range of design basis alternatives is considered to determine if this would influence the relative economics of the two waste forms. A thermal analysis procedure was utilized to define optimum canister sizes to assure that each waste form was compared under favorable conditions. Repository costs are found to favor the borosilicate glass waste form while transportation costs greatly favor the crystalline ceramic waste form. The determining component in the cost comparison is the waste processing cost, which strongly favors the borosilicate glass process because of its relative simplicity. A net cost advantage on the order of 12% to 15% on a waste management system basis is indicated for the glass waste form

  16. High level waste containing granules coated and embedded in metal as an alternative to HLW glasses

    Neumann, W.

    1980-01-01

    Simulated high level waste containing granules were overcoated with pyrocarbon or nickel respectively. The coatings were performed by the use of chemical vapour deposition in a fluidized bed. The coated granules were embedded in an aluminium-silicon-alloy to improve the dissipation of radiation induced heat. The metal-granules-composites obtained were of improved product stability related to the high level waste containing glasses. (orig.) [de

  17. Transuranium elements leaching from simulated HLW glasses in synthetic interstitial claywater

    Wang, L.

    1992-08-01

    The main objective of this Master Thesis is to measure the steady-state concentrations of Pu, Np, and Am upon the leaching of High-Level Waste Glass in two types of synthetic claywater: humic acid free and humic acid containing synthetic claywater. The synthetic claywater has a composition that is representative for the in-situ interstitial groundwater of the Boom clay formation, a potential geological repository of radioactive waste in Belgium. The steady-state concentrations of transuranium elements were measured by leaching experiments with a typical duration of 400 days. Five main conclusions are drawn from the experimental data. (1) The transuranium elements that are released from simulated High Level Waste Glass are dominantly present in the synthetic claywater solutions as colloids. These colloids are smaller than 2 nm in absence of humic acids. In the presence of humic acids however, the colloids interact with actinides (adsorb or coagulate) and form particles larger than 2 nm. Np and Am are associated with inorganic and organic colloids in the synthetic interstitial claywater solution whereas Pu forms only inorganic colloids. (2) The steady-state concentration of Pu is in good agreement with the solubility of the Pu compound PuO 2 .xH 2 O. It is therefore concluded that PuO 2 .xH 2 O is the solubility controlling phase. (3) The Pu(IV)-species are dominant in the leaching solutions. Carbonate and humic acid complexes are negligible. (4) The steady-state concentrations of Np and Am in leaching solutions were much lower than the values calculated on the basis of known thermodynamic data. This indicates that the solubility controlling phases for Np and Am were not correctly identified or that the measured Np and Am concentrations were not steady-state values. (5) Non-active glass leaching tests have indicated that no organic colloids were formed as a result of glass dissolution. (A.S.)

  18. Preparation of fullerene/glass composites

    Mattes, Benjamin R.; McBranch, Duncan W.; Robinson, Jeanne M.; Koskelo, Aaron C.; Love, Steven P.

    1995-01-01

    Synthesis of fullerene/glass composites. A direct method for preparing solid solutions of C.sub.60 in silicon dioxide (SiO.sub.2) glass matrices by means of sol-gel chemistry is described. In order to produce highly concentrated fullerene-sol-gel-composites it is necessary to increase the solubility of these "guests" in a delivery solvent which is compatible with the starter sol (receiving solvent). Sonication results in aggregate disruption by treatment with high frequency sound waves, thereby accelerating the rate of hydrolysis of the alkoxide precursor, and the solution process for the C.sub.60. Depending upon the preparative procedure, C.sub.60 dispersed within the glass matrix as microcrystalline domains, or dispersed as true molecular solutions of C.sub.60 in a solid glass matrix, is generated by the present method.

  19. Use of natural and archaeological analogs to validate long - term behaviour of HLW glass in geological disposal conditions

    Gin, S.; Verney-Carron, A.; Libourel, G.

    2008-01-01

    Some old basaltic and Roman glasses have been studied in order to validate the predictive models developed for assessing the long-term behaviour of nuclear glass in geological repository conditions. Leaching behaviour of basaltic glass altered in both laboratory and natural environment conditions allows to validate the key mechanisms that control glass dissolution kinetics and the order of magnitude of glass packages lifetime In a stable clayey formation (French reference concept for a geological disposal of high level waste). The study of Roman glass blocks (with the same geometry as nuclear glass package) altered during 1800 years in a marine environment gives new insight on the basic mechanisms involved in confined media (fractures and small cracks). Results show the importance of the coupling between transport of reactive species and chemical reactions. This study, still in progress, would allow to validate the modelling of such a complex system. (author)

  20. R7T7-type HLW glass alteration under irradiation. Study of the residual alteration rate regime

    Rolland, Severine

    2012-01-01

    In France, fission products and minor actinides remaining after reprocessing of spent nuclear fuel are confined in a borosilicate glass matrix, named R7T7, for disposal in a geological repository. However, in these conditions, after several thousand years, water could arrive in contact with glass and be radio-lysed. In this work, we investigated the irradiation influence and especially the influence of the energy deposition on the residual glass alteration rate regime in pure water. Two types of leaching tests have been carried out. The first were performed on radioactive glass and the second on a SON68 glass (nonradioactive surrogate of R7T7 glass) under external irradiation γ. (author) [fr

  1. Melter Throughput Enhancements for High-Iron HLW

    Kruger, A. A. [Department of Energy, Office of River Protection, Richland, Washington (United States); Gan, Hoa [The Catholic University of America, Washington, DC (United States); Joseph, Innocent [The Catholic University of America, Washington, DC (United States); Pegg, Ian L. [The Catholic University of America, Washington, DC (United States); Matlack, Keith S. [The Catholic University of America, Washington, DC (United States); Chaudhuri, Malabika [The Catholic University of America, Washington, DC (United States); Kot, Wing [The Catholic University of America, Washington, DC (United States)

    2012-12-26

    This report describes work performed to develop and test new glass and feed formulations in order to increase glass melting rates in high waste loading glass formulations for HLW with high concentrations of iron. Testing was designed to identify glass and melter feed formulations that optimize waste loading and waste processing rate while meeting all processing and product quality requirements. The work included preparation and characterization of crucible melts to assess melt rate using a vertical gradient furnace system and to develop new formulations with enhanced melt rate. Testing evaluated the effects of waste loading on glass properties and the maximum waste loading that can be achieved. The results from crucible-scale testing supported subsequent DuraMelter 100 (DM100) tests designed to examine the effects of enhanced glass and feed formulations on waste processing rate and product quality. The DM100 was selected as the platform for these tests due to its extensive previous use in processing rate determination for various HLW streams and glass compositions.

  2. Thin films prepared from tungstate glass matrix

    Montanari, B.; Ribeiro, S.J.L.; Messaddeq, Y. [Departamento de Quimica Geral e Inorganica, Instituto de Quimica, Sao Paulo State University-UNESP, CP 355, CEP 14800-900, Araraquara, SP (Brazil); Li, M.S. [Instituto de Fisica, USP, CP 369, CEP 13560-970, Sao Carlos, SP (Brazil); Poirier, G. [Departamento de Ciencias Exatas, UNIFAL-MG, CEP 37130-000, Alfenas-MG (Brazil)], E-mail: gael@unifal-mg.edu.br

    2008-01-30

    Vitreous samples containing high concentrations of WO{sub 3} (above 40% M) have been used as a target to prepare thin films. Such films were deposited using the electron beam evaporation method onto soda-lime glass substrates. These films were characterized by X-ray diffraction (XRD), perfilometry, X-ray energy dispersion spectroscopy (EDS), M-Lines and UV-vis absorption spectroscopy. In this work, experimental parameters were established to obtain stable thin films showing a chemical composition close to the glass precursor composition and with a high concentration of WO{sub 3}. These amorphous thin films of about 4 {mu}m in thickness exhibit a deep blue coloration but they can be bleached by thermal treatment near the glass transition temperature. Such bleached films show several guided modes in the visible region and have a high refractive index. Controlled crystallization was realized and thus it was possible to obtain WO{sub 3} microcrystals in the amorphous phase.

  3. Properties of Formula 127 glass prepared with radioactive zirconia calcine

    Staples, B.A.; Pavlica, D.A.; Cole, H.S.

    1982-09-01

    Formula 127 glass has been developed to immobilize ICPP zirconia calcine. This glass has been prepared remotely on a laboratory scale basis with actual radioactive zirconia calcine retrieved after ten years of storage from Bin Set 2. The aqueous leachability of the glass produced was investigated and compared through application of the MCC-1, MCC-2 and Soxhlet leach tests with that of Formula 127 glass prepared with simulated calcine. The solid state properties of the glasses prepared with actual and simulated calcines were also measured by electron spectroscopy for chemical analysis (ESCA) and scanning electron microscopy energy dispersive x-ray (SEM-EDX). Based on the application of these leaching tests and analysis techniques the properties measured in this study are similar for 127 glass prepared with either simulated or radioactive calcine. 13 figures, 16 tables

  4. Influence of foaming agents on solid thermal conductivity of foam glasses prepared from CRT panel glass

    Østergaard, Martin Bonderup; Petersen, Rasmus Rosenlund; König, Jakob

    2017-01-01

    The understanding of the thermal transport mechanism of foam glass is still lacking. The contribution of solid- and gas conduction to the total thermal conductivity remains to be reported. In many foam glasses, the solid phase consist of a mix of an amorphous and a crystalline part where foaming...... containing glass and crystalline foaming agents and amorphous samples where the foaming agents are completely dissolved in the glass structure, respectively. Results show that the samples prepared by sintering have a higher thermal conductivity than the samples prepared by melt-quenching. The thermal...... conductivities of the sintered and the melt-quenched samples represent an upper and lower limit of the solid phase thermal conductivity of foam glasses prepared with these foaming agents. The content of foaming agents dissolved in the glass structure has a major impact on the solid thermal conductivity of foam...

  5. Safety of HLW shipments

    1998-01-01

    The third shipment back to Japan of vitrified high-level radioactive waste (HLW) produced through reprocessing in France is scheduled to take place in early 1998. A consignment last March drew protest from interest groups and countries along the shipping route. Requirements governing the shipment of cargoes of this type and concerns raised by Greenpeace that were assessed by an international expert group, were examined in a previous article. A further report prepared on behalf of Greenpeace Pacific has been released. The paper: Transportation accident of a ship carrying vitrified high-level radioactive waste, Part 1 Impact on the Federated States of Micronesia by Resnikoff and Champion, is dated 31 July 1997. A considerable section of the report is given over to discussion of the economic situation of the Federated Statess of Micronesia, and lifestyle and dietary factors which would influence radiation doses arising from a release. It postulates a worst case accident scenario of a collision between the HLW transport ship and an oil tanker 1 km off Pohnpei with the wind in precisely the direction to result in maximum population exposure, and attempts to assess the consequences. In summary, the report postulates accident and exposure scenarios which are conceivable but not credible. It combines a series of worst case scenarios and attempts to evaluate the consequences. Both the combined scenario and consequences have probabilities of occurrence which are negligible. The shipment carried by the 'Pacific Swan' left Cherbourgon 21 January 1998 and comprised 30 tonnes of reprocessed vitrified waste in 60 stainless steel canisters loaded into three shipping casks. (author)

  6. DM100 AND DM1200 MELTER TESTING WITH HIGH WASTE LOADING FORMULATIONS FOR HANFORD HIGH-ALUMINUM HLW STREAMS, TEST PLAN 09T1690-1

    Kruger, A.A.; Matlack, K.S.; Kot, W.K.; Pegg, I.L.; Joseph, I.

    2009-01-01

    This Test Plan describes work to support the development and testing of high waste loading glass formulations that achieve high glass melting rates for Hanford high aluminum high level waste (HLW). In particular, the present testing is designed to evaluate the effect of using low activity waste (LAW) waste streams as a source of sodium in place ofchemical additives, sugar or cellulose as a reductant, boehmite as an aluminum source, and further enhancements to waste processing rate while meeting all processing and product quality requirements. The work will include preparation and characterization of crucible melts in support of subsequent DuraMelter 100 (DM 100) tests designed to examine the effects of enhanced glass formulations, glass processing temperature, incorporation of the LAW waste stream as a sodium source, type of organic reductant, and feed solids content on waste processing rate and product quality. Also included is a confirmatory test on the HLW Pilot Melter (DM1200) with a composition selected from those tested on the DM100. This work builds on previous work performed at the Vitreous State Laboratory (VSL) for Department of Energy's (DOE's) Office of River Protection (ORP) to increase waste loading and processing rates for high-iron HLW waste streams as well as previous tests conducted for ORP on the same waste composition. This Test Plan is prepared in response to an ORP-supplied statement of work. It is currently estimated that the number of HLW canisters to be produced in the Hanford Tank Waste Treatment and Immobilization Plant (WTP) is about 12,500. This estimate is based upon the inventory ofthe tank wastes, the anticipated performance of the sludge treatment processes, and current understanding of the capability of the borosilicate glass waste form. The WTP HLW melter design, unlike earlier DOE melter designs, incorporates an active glass bubbler system. The bubblers create active glass pool convection and thereby improve heat transfer and

  7. Preparation of basalt-based glass ceramics

    MIHOVIL LOGAR

    2003-06-01

    Full Text Available Local and conventional raw materials–massive basalt from the Vrelo locality on Kopaonik mountain–have been used as starting materials to test their suitability for the production of glass-ceramics. Crystallization phenomena of glasses of the fused basalt rocks were studied by X-ray phase analysis, optical microscopy and other techniques. Various heat treatments were used, and their influences, on controlling the microstructures and properties of the products were studied with the aim of developing high strength glass-ceramic materials. Diopside CaMg(SiO32 and hypersthene ((Mg,FeSiO3 were identifies as the crystalline phases. The final products contained considerable amounts of a glassy phase. The crystalline size was in range of 8–480 mm with plate or needle shape. Microhardness, crashing strength and wears resistence of the glass-ceramics ranged from 6.5–7.5, from 2000–6300 kg/cm2 and from 0.1–0.2 g/cm, respectively.

  8. Molecular glasses for nuclear waste encapsulation

    Ropp, R.C.

    1982-01-01

    The use of a molecular glass based upon a polymerized phosphate of aluminum (PAP), indium or gallium overcomes all of the prior objections to use of glass as a high-level nuclear waste (HLW) encapsulation agent. This HLW glass product could not be made to devitrify, dissolved all of the oxides found in calcine, including the difficultly soluble ones, did not form microcrystallites in the melt or subsequent glass-casting, and possessed a hydrolytic etching rate to boiling water even lower than that of HLW-ZBS glass. A precursor compound, M(H 2 PO 4 ) 3 , is prepared, where M is a trivalent metal selected from the group consisting of aluminum, indium and gallium. The impurity level is carefully controlled so as not to exceed 300 ppm total. The precursor crystals may be washed to remove excess phosphoric acid as desired. HLW is added to the crystals and the mixture is then heated at a controlled heating rate to induce solid state polymerization and to form a melt at 1350 degrees C in which the HLW oxides dissolve rapidly

  9. Characterization of iron phosphate glasses prepared by microwave heating

    Almeida, Fabio Jesus Moreira de

    2006-01-01

    Phosphate glasses have been investigated since the fifties, because they are relatively easy to prepare, have low melting temperatures (1000 deg C - 1200 deg C and low glass transition. However, these glasses were very sensitive to humidity, showing a very low chemical durability. Iron phosphate glasses have been prepared by melting inorganic precursors in conventional electric furnaces and induction furnaces. By adding iron, phosphate glasses became chemical resistant and were thought to be used as nuclear waste forms or mechanical resistance fibers. The use of microwaves has been investigated because it makes possible a fast and homogeneous heating of the materials. Microwave promotes the self-heating of the material by the interaction of the external electromagnetic field with the molecules and ions of the material. Niobium phosphate glasses was also produced already through the heating of precursors in microwave ovens. Other glasses containing iron in theirs structure was produced by conventional furnaces and they had your structures analyzed. But even so, it was not still published synthesis of iron phosphate glasses starting from the melting of precursors materials in microwave ovens. In the present work mixtures of (NH 4 ) 2 HPO 4 and Fe 3 O 4 or (NH 4 ) 2 HPO 4 and Fe 2 O 3 were exposed to microwave energy with electromagnetic waves of 2,45 GHz. It was proposed that the absorption of this radiation for the material causes the heating from room temperature to melting temperature. The obtained iron phosphate glasses was analyzed by X-ray diffraction, Moessbauer spectroscopy, and Differential Thermal Analysis. Iron phosphate glasses were also produced in electrical furnaces for comparison. (author)

  10. Characterization of iron phosphate glasses prepared by microwave heating

    Almeida, Fabio Jesus Moreira de

    2006-01-01

    Phosphate glasses have been investigated since the fifties, because they are relatively easy to prepare, have low melting temperatures (1000 deg C - 1200 deg C), and low glass transition. However, these glasses were very sensitive to humidity, showing a very low chemical durability. Iron phosphate glasses have been prepared by melting inorganic precursors in conventional electric furnaces and induction furnaces. By adding iron, phosphate glasses became chemical resistant and were thought to be used as nuclear waste forms or mechanical resistance fibers. The use of microwaves has been investigated because it makes possible a fast and homogeneous heating of the materials. Microwave promotes the self-heating of the material by the interaction of the external electromagnetic field with the molecules and ions of the material. Niobium phosphate glasses was also produced already through the heating of precursors in microwave ovens. Other glasses containing iron in theirs structure was produced by conventional furnaces and they had your structures analyzed. But even so, it was not still published synthesis of iron phosphate glasses starting from the melting of precursors materials in microwave ovens. In the present work mixtures of (NH 4 ) 2 HPO 4 and Fe 3 O 4 or (NH 4 ) 2 HPO 4 and Fe 2 O 3 were exposed to microwave energy with electromagnetic waves of 2,45 GHz. It was proposed that the absorption of this radiation for the material causes the heating from room temperature to melting temperature. The obtained iron phosphate glasses was analyzed by X-ray diffraction, Moessbauer spectroscopy, and Differential Thermal Analysis. Iron phosphate glasses were also produced in electrical furnaces for comparison. (author)

  11. Memo, "Incorporation of HLW Glass Shell V2.0 into the Flowsheets," to ED Lee, CCN: 184905, October 20, 2009

    Gimpel, Rodney F.; Kruger, Albert A.

    2013-12-18

    Efforts are being made to increase the efficiency and decrease the cost of vitrifying radioactive waste stored in tanks at the U.S. Department of Energy Hanford Site. The compositions of acceptable and processable high-level waste (HL W) glasses need to be optimized to minimize the waste-form volume and, hence, to reduce cost. A database of glass properties of waste glass and associated simulated waste glasses was collected and documented in PNNL 18501, Glass Property Data and Models for Estimating High-Level Waste Glass Volume and glass property models were curve-fitted to the glass compositions. A routine was developed that estimates HL W glass volumes using the following glass property models: II Nepheline, II One-Percent Crystal Temperature (T1%), II Viscosity (11) II Product Consistency Tests (PCT) for boron, sodium, and lithium, and II Liquidus Temperature (TL). The routine, commonly called the HL W Glass Shell, is presented in this document. In addition to the use of the glass property models, glass composition constraints and rules, as recommend in PNNL 18501 and in other documents (as referenced in this report) were incorporated. This new version of the HL W Glass Shell should generally estimate higher waste loading in the HL W glass than previous versions.

  12. Preparing as an organization to review a construction license application for a DGR for HLW and SF in the USA

    Hill, Brittain

    2014-01-01

    Although formally opposed by the State of Nevada, the Yucca Mountain site (Nevada) recommendation was approved by the U.S. Congress and the President, which authorized DOE to prepare and submit a license application for a deep geologic repository for the nation's spent nuclear fuel and high-level waste. In June of 2008, DOE submitted this application to the U.S. Nuclear Regulatory Commission (NRC) for its review and formal adjudication of contested issues during a 3-4 year period. Although subsequent actions by the Administration and Congress have changed the direction for geologic disposal in the U.S., the NRC staff was able to conduct a thorough technical review of the DOE license application and issue technical evaluation reports before the review and hearings were suspended in September 2011. This paper provides the author's perspective on how the NRC prepared for, and conducted, this first-of-a-kind licensing review: planning framework, key preparations for staff and for processes, events after the receipt of a license application, retrospective on staff preparations and on processes. By the end of September 2011, the NRC staff had issued three Technical Evaluation Reports using a risk-informed, performance-based approach to review the DOE license application for this deep geologic repository at Yucca Mountain

  13. Preparation and characterization of boro-tellurite glasses

    Kaur, Nirmal; Khanna, Atul; Krishna, P. S. R.

    2014-04-01

    Glass samples of the system: xB2O3-(100-x) TeO2; x= 15, 20, 25 and 30 mol% were prepared by melt quenching and characterized by X-ray diffraction, density measurements, Differential Scanning Calorimetry and FTIR spectroscopy. XRD confirmed the amorphous structure of all samples. Density of glasses decreased with increase in B2O3 concentration due to the replacement of heavier TeO2 with lighter B2O3 whereas the glass transition temperature increased from 339°C to 366°C; the later effect was due to increase in the concentration of stronger B-O bonds in the glass network. FTIR studies found that BO4 units convert into BO3 with the addition of B2O3.

  14. Preparation and characterization of boro-tellurite glasses

    Kaur, Nirmal, E-mail: akphysics@yahoo.com; Khanna, Atul, E-mail: akphysics@yahoo.com [Glass Physics and Sensors Laboratory, Department of Physics, Guru Nanak Dev University, Amritsar-143005, Punjab (India); Krishna, P. S. R. [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai-400085, Maharashtra (India)

    2014-04-24

    Glass samples of the system: xB{sub 2}O{sub 3}−(100−x) TeO{sub 2}; x= 15, 20, 25 and 30 mol% were prepared by melt quenching and characterized by X-ray diffraction, density measurements, Differential Scanning Calorimetry and FTIR spectroscopy. XRD confirmed the amorphous structure of all samples. Density of glasses decreased with increase in B{sub 2}O{sub 3} concentration due to the replacement of heavier TeO{sub 2} with lighter B{sub 2}O{sub 3} whereas the glass transition temperature increased from 339°C to 366°C; the later effect was due to increase in the concentration of stronger B-O bonds in the glass network. FTIR studies found that BO{sub 4} units convert into BO{sub 3} with the addition of B{sub 2}O{sub 3}.

  15. Characterization of HLW glass samples Task 3 Characterization of radioactive waste forms a series of final reports (1985-89) No 20

    Malow, G.; Behrend, U.; Schubert, P.

    1991-01-01

    Due to a delay in the melting of the highly radioactive SON68 glass, a short-term post-investigation of the highly radioactive glass from the Pamela plant in Mol (Belgium) has been carried out, the aim being a check-up of the active LEWC glass SM 513 LW11. The results were compared with those obtained for non-radioactive glass samples. The final report of the present CEC programme shortly describes the planned investigations of the glass R7T7 for the whole period of the research contract and the results of the short-term post-investigation of the Pamela glass. 11 refs.; 9 figs.; 4 tabs

  16. MIIT: International in-situ testing of simulated HLW forms--preliminary analyses of SRL 165/TDS waste glass and metal systems

    Wicks, G.G.; Lodding, A.R.; Macedo, P.B.; Molecke, M.A.

    1989-01-01

    The first in-situ tests involving burial of simulated high-level waste (HLW) forms conducted in the United States were started on July 22, 1986. This effort, called the Materials Interface Interactions Tests (MIIT), comprises the largest, most cooperative field testing venture in the international waste management community. Included in the study are over 900 waste form samples comprising 15 different systems supplied by seven countries. Also included are almost 300 potential canister or overpack metal samples of 11 different metals along with more than 500 geologic and backfill specimens. There are a total of 1926 relevant interactions that characterize this effort which is being conducted in the bedded salt site at the Waste Isolation Pilot Plant (WIPP), near Carlsbad, New Mexico

  17. Microwave and conventional preparation of Zinc borate glass: Eu3+ ion as luminescent probe

    Mandal, Ashis K.; Balaji, S.; Sen, Ranjan

    2014-01-01

    Highlights: • IR transparent Zinc borate glass is prepared using microwave heating. • Glass transition temperature of microwave melted glass is found higher than that of glass prepared in conventional melting. • Low OH concentration in glass can be prepared in microwave heating. • We report higher reduction of Eu 3+ to Eu 2+ in microwave processing of Zinc borate glass. - Abstract: Transparent Zinc borate glass is melted using microwave energy as an alternative heating route to conventional resistive heating. A comparative study of the properties of the glasses prepared by both the methods is conducted by adopting X-ray diffraction (XRD), Differential scanning calorimetry (DSC), UV–VIS–NIR spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Refractive Indices (RI). Amorphous nature of samples is confirmed by X-ray diffraction study. Glass transition temperature (T g ) of microwave melted glass is found ∼7–9 °C higher than that of glass prepared in conventional melting. OH content is found less than 250 ppm in microwave melted glass whereas it is above 330 ppm in conventional melted glasses. Photoluminescence study of Eu 2 O 3 doped glass prepared in microwave heating indicates higher reduction of Eu 3+ → Eu 2+ than the glass melted in conventional route. Thus, microwave processing can be an alternative energy efficient, time saving, environmental friendly glass preparation method

  18. The effect of sample preparation methods on glass performance

    Oh, M.S.; Oversby, V.M.

    1990-01-01

    A series of experiments was conducted using SRL 165 synthetic waste glass to investigate the effects of surface preparation and leaching solution composition on the alteration of the glass. Samples of glass with as-cast surfaces produced smooth reaction layers and some evidence for precipitation of secondary phases from solution. Secondary phases were more abundant in samples reacted in deionized water than for those reacted in a silicate solution. Samples with saw-cut surfaces showed a large reduction in surface roughness after 7 days of reaction in either solution. Reaction in silicate solution for up to 91 days produced no further change in surface morphology, while reaction in DIW produced a spongy surface that formed the substrate for further surface layer development. The differences in the surface morphology of the samples may create microclimates that control the details of development of alteration layers on the glass; however, the concentrations of elements in leaching solutions show differences of 50% or less between samples prepared with different surface conditions for tests of a few months duration. 6 refs., 7 figs., 1 tab

  19. COMSOL Multiphysics Model for HLW Canister Filling

    Kesterson, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-04-11

    The U.S. Department of Energy (DOE) is building a Tank Waste Treatment and Immobilization Plant (WTP) at the Hanford Site in Washington to remediate 55 million gallons of radioactive waste that is being temporarily stored in 177 underground tanks. Efforts are being made to increase the loading of Hanford tank wastes in glass while meeting melter lifetime expectancies and process, regulatory, and product quality requirements. Wastes containing high concentrations of Al2O3 and Na2O can contribute to nepheline (generally NaAlSiO4) crystallization, which can sharply reduce the chemical durability of high level waste (HLW) glass. Nepheline crystallization can occur during slow cooling of the glass within the stainless steel canister. The purpose of this work was to develop a model that can be used to predict temperatures of the glass in a WTP HLW canister during filling and cooling. The intent of the model is to support scoping work in the laboratory. It is not intended to provide precise predictions of temperature profiles, but rather to provide a simplified representation of glass cooling profiles within a full scale, WTP HLW canister under various glass pouring rates. These data will be used to support laboratory studies for an improved understanding of the mechanisms of nepheline crystallization. The model was created using COMSOL Multiphysics, a commercially available software. The model results were compared to available experimental data, TRR-PLT-080, and were found to yield sufficient results for the scoping nature of the study. The simulated temperatures were within 60 ºC for the centerline, 0.0762m (3 inch) from centerline, and 0.2286m (9 inch) from centerline thermocouples once the thermocouples were covered with glass. The temperature difference between the experimental and simulated values reduced to 40 ºC, 4 hours after the thermocouple was covered, and down to 20 ºC, 6 hours after the thermocouple was covered

  20. Preparation of mica/apatite glass-ceramics biomaterials

    Liu Yong; Sheng Xiaoxian; Dan Xiaohong; Xiang Qijun

    2006-01-01

    Glass-ceramics have become more and more important biomaterials. In this work mica glass/apatite composites with various compositions were prepared by casting and subsequent heat treatments. The effects of composition, phase constitution and crystallinity on mechanical properties, including elastic modulus and transverse rupture strength (TRS), were investigated by using X-ray diffraction analyses (XRD), scanning electron microscopy (SEM) and mechanical tests. Results show that addition of apatite composition in mica glass accelerates the crystallization process and induces the formation of fluoroapatite phase, and the nucleation of apatite crystals occurs before that of mica crystals. The fuoroapatite in this work is needle-like, which is almost the same to that in human bone. The transverse rupture strength increases with the content of fluoroapatite and the crystallinity increasing, except that at a low apatite content the mechanical properties are lower than those of mica glass under the same processing conditions. The transverse rupture strength and elastic modulus obtained in this work fall in the range of those of human bone. SBF immersion test demonstrates good bioactivity of this biomaterial

  1. Technetium Chemistry in HLW

    Hess, Nancy J.; Felmy, Andrew R.; Rosso, Kevin M.; Xia Yuanxian

    2005-01-01

    Tc contamination is found within the DOE complex at those sites whose mission involved extraction of plutonium from irradiated uranium fuel or isotopic enrichment of uranium. At the Hanford Site, chemical separations and extraction processes generated large amounts of high level and transuranic wastes that are currently stored in underground tanks. The waste from these extraction processes is currently stored in underground High Level Waste (HLW) tanks. However, the chemistry of the HLW in any given tank is greatly complicated by repeated efforts to reduce volume and recover isotopes. These processes ultimately resulted in mixing of waste streams from different processes. As a result, the chemistry and the fate of Tc in HLW tanks are not well understood. This lack of understanding has been made evident in the failed efforts to leach Tc from sludge and to remove Tc from supernatants prior to immobilization. Although recent interest in Tc chemistry has shifted from pretreatment chemistry to waste residuals, both needs are served by a fundamental understanding of Tc chemistry

  2. MIIT: International in-situ testing of simulated HLW forms - performance of SRS simulated waste glass after 6 mos., 1 yr., 2 yrs. and 5 yrs. of burial at WIPP

    Wicks, G.G.; Lodding, A.R.; Macedo, P.B.; Clark, D.E.

    1991-01-01

    The first field test, involving burial of simulated high-level waste (HLW) forms and package components, to be conducted in the United States, was begun in July of 1986. This program, called the Materials Interface Interactions Test or MIIT, comprises the largest cooperative field-testing venture in the international waste management community. Included in the study are over 900 waste form samples comprising 15 different systems supplied by 7 countries. Also included are about 300 potential canister or overpack metal samples along with more than 500 geologic and backfill specimens. There are almost 2000 relevant interactions that characterize this effort which is being conducted in the bedded salt site at the Waste Isolation Pilot Plant (WIPP), near Carlsbad, New Mexico. The MIIT program represents a joint effort managed by Sandia National Laboratories in Albuquerque, N.M., and Savannah River Laboratory in Aiken, S.C. and sponsored by the US Department of Energy. Also involved in MIIT are participants from various laboratories and universities in France, Germany, Belgium, Canada, Japan, Sweden, the United Kingdom, and the United States. In July of 1991, the experimental portion of the 5-yr. MIIT program was completed. Although only about 5% of all MIIT samples have been assessed thus far, there are already interesting findings that have emerged. The present paper will discuss results obtained for SRS 165/TDS waste glass after burial of 6 mo., 1 yr. and 2 yrs., along with initial analyses of 5 yr. samples

  3. Preparation and characterisation of glass surfaces for experimental purposes

    Serruys, Y.

    1986-01-01

    Experimental investigation of glasses, applied especially to the prevision of the behaviour of vitrified nuclear wastes, requires the preparation of well-defined and reproducibles surfaces, in order to separate the investigated phenomena from artifacts due to surface anomalies and to allow a valuable comparison between results obtained in different laboratories. The aim of the present report is to determine which characters, both physical and chemical, of glass surfaces, have to be controlled, because of their influence upon the investigated phenomena or the experimental processes employed in the investigation. A method is then presented for a surface preparation giving good guaranties of quality and reproducibility. The physical and chemical aspects of surface characterisation are successively considered. The relevant characters and their importance are described, then the corresponding techniques of characterisation are reviewed and it has been attempted to propose a set of techniques allowing a characterisation as complete as possible for laboratory purposes. A preparation method for experimental sample, aiming to satisfy all the previously defined criteria, is then proposed, and present results obtained with this method are described [fr

  4. Sintering process of Eu doped luminescent glass prepared from porous glass

    Akai, T; Murakami, M; Yamashita, M; Okajima, T; Umesaki, N

    2011-01-01

    Eu doped high silica glass prepared by sintering porous glass exhibits blue luminescence with high quantum efficiency. In this work, we studied effects of sintering temperature on valance state of europium ion. To investigate a change of valance state of Eu, X-ray absorption near edge structure (XANES) spectroscopy measurements were carried out. Intensity of blue emission at around 430nm drastically increases when the sintering temperature is above 1000 deg. C. From XANES spectra, it is found that almost all the Eu exist as Eu 3+ in a samples sintered below 900 deg. C, while more than 70% of Eu exist as Eu 2+ in the sample sintered at 1050 deg. C and 1100 deg. C. The drastic change of oxidation state of europium ion between 900 and 1050 deg. C is discussed in relation to the structural change probed by infrared (IR) spectroscopy.

  5. Industrial scale-plant for HLW partitioning in Russia

    Dzekun, E.G.; Glagolenko, Y.V.; Drojko, E.G.; Kurochkin, A.I.

    1996-01-01

    Radiochemical plant of PA > at Ozersk, which was come on line in December 1948 originally for weapon plutonium production and reoriented on the reprocessing of spent fuel, till now keeps on storage HLW of the military program. Application of the vitrification method since 1986 has not essentially reduced HLW volumes. So, as of September 1, 1995 vitrification installations had been processed 9590 m 3 HLW and 235 MCi of radionuclides was included in glass. However only 1100 m 3 and 20.5 MCi is part of waste of the military program. The reason is the fact, that the technology and equipment of vitrification were developed for current waste of Purex-process, for which low contents of corrosion-dangerous impurity to materials of vitrification installation is characteristic of. With reference to HLW, which are growing at PA > in the course of weapon plutonium production, the program of Science-Research Works includes the following main directions of work. Development of technology and equipment of installations for immobilising HLW with high contents of impurity into a solid form at induction melter. Application of High-temperature Adsorption Method for sorption of radionuclides from HLW on silica gel. Application of Partitioning Method of radionuclides from HLW, based on extraction cesium and strontium into cobalt dicarbollyde or crown-ethers, but also on recovery of cesium radionuclides by sorption on inorganic sorbents. In this paper the results of work on creation of first industrial scale-plant for partitioning HLW by the extraction and sorption methods are reported

  6. Source term measurements on vitrified HLW

    Hough, A.; Marples, J.A.C.

    1988-01-01

    The equilibrium concentrations of Tc-99, Np-237, Pu-239/240 and Am-241 have been measured in the presence of materials likely to be present in a vitrified HLW repository: glass, iron, backfill and rock. Results were measured under both oxidising and reducing conditions and at pH values set by the backfill bentonite and cement. Under reducing conditions and with cementitious backfills, the equilibrium concentrations ranged from three to 30 times allowed drinking water levels for the four isotopes. (author)

  7. HLW Disposal System Development

    Choi, J. W.; Choi, H. J.; Lee, J. Y. (and others)

    2007-06-15

    A KRS is suggested through design requirement analysis of the buffer and the canister which are the constituent of disposal system engineered barrier and HLW management plans are proposed. In the aspect of radionuclide retention capacity, the thickness of the buffer is determined 0.5m, the shape to be disc and ring and the dry density to be 1.6 g/cm{sup 3}. The maximum temperature of the buffer is below 100 .deg. which meets the design requirement. And bentonite blocks with 5 wt% of graphite showed more than 1.0 W/mK of thermal conductivity without the addition of sand. The result of the thermal analysis for proposed double-layered buffer shows that decrease of 7 .deg. C in maximum temperature of the buffer. For the disposal canister, the copper for the outer shell material and cast iron for the inner structure material is recommended considering the results analyzed in terms of performance of the canisters and manufacturability and the geochemical properties of deep groundwater sampled from the research area with granite, salt water intrusion, and the heavy weight of the canister. The results of safety analysis for the canister shows that the criticality for the normal case including uncertainty is the value of 0.816 which meets subcritical condition. Considering nation's 'Basic Plan for Electric Power Demand and Supply' and based on the scenario of disposing CANDU spent fuels in the first phase, the disposal system that the repository will be excavated in eight phases with the construction of the Underground Research Laboratory (URL) beginning in 2020 and commissioning in 2040 until the closure of the repository is proposed. Since there is close correlation between domestic HLW management plans and front-end/back-end fuel cycle plans causing such a great sensitivity of international environment factor, items related to assuring the non-proliferation and observing the international standard are showed to be the influential factor and acceptability

  8. High-Level Waste Glass Formulation Model Sensitivity Study 2009 Glass Formulation Model Versus 1996 Glass Formulation Model

    Belsher, J.D.; Meinert, F.L.

    2009-01-01

    This document presents the differences between two HLW glass formulation models (GFM): The 1996 GFM and 2009 GFM. A glass formulation model is a collection of glass property correlations and associated limits, as well as model validity and solubility constraints; it uses the pretreated HLW feed composition to predict the amount and composition of glass forming additives necessary to produce acceptable HLW glass. The 2009 GFM presented in this report was constructed as a nonlinear optimization calculation based on updated glass property data and solubility limits described in PNNL-18501 (2009). Key mission drivers such as the total mass of HLW glass and waste oxide loading are compared between the two glass formulation models. In addition, a sensitivity study was performed within the 2009 GFM to determine the effect of relaxing various constraints on the predicted mass of the HLW glass.

  9. Fabrication of Radiation Shielding Glasses Based on Lead-free High Refractive Index Glasses Prepared from Local Sand

    Dararutana, Pisutti; Dutchaneepet, Jirapan; Sirikulrat, Narin

    2007-08-01

    Full text: Lead glasses that show high refractive index are the best know and most popular for radiation shielding. Due to harmful effects of lead and considering the health as well as the environmental issues, lead-free glasses were developed. In this work, content of Chumphon sand was fixed at 40 % (by weight) as a main composition but concentrations of BaCO3 were varied from 6 to 30 % (by weight). It was found that the absorption coefficient of the glass samples containing 30 % BaCO3 was 0.233 cm-1 for Ba-133. The density was also measured. It can be concluded that the prepared lead free glasses offered adequate shielding to gamma radiation in comparison with the lead ones. These glasses were one of the environmental friendly materials

  10. The basic corrosion mechanisms of HLW glasses

    Conradt, R.; Roggendorf, H.; Ostertag, R.

    1986-01-01

    During the years 1975 to 1984, the Commission of the European Communities organized and promoted an R and D programme on the testing and evaluation of solidified high-level waste forms with the purpose of providing a scientific basis for the management and storage of radioactive waste. A fair number of materials were tested under a broad variation of experimental data. The Fraunhofer-Institut fuer Silicatforschung, Wuerzburg, has undertaken to perform a synoptic evaluation of the above data. The purpose of this evaluation is: - to compile the data from the individual national contributors (as presented in the joint annual reports of the EC) with respect to: the materials, or the experimental parameters, or further aspects, and to harmonize them with respect to their presentation, choice of units, etc., - to compare the results to the international state of information, - to elaborate and demonstrate common features of the diverse materials, e.g. common patterns of the corrosion behaviour, - to check the validity of present models, - to define shortcomings and questions that are still open

  11. Preparation and leaching property of Nd-doped zirconolite-based glass-ceramic

    Wu Lang; Xu Dong; Teng Yuancheng; Li Yuxiang; Liu Zongqiang

    2014-01-01

    Nd-doped zirconolite-based glass-ceramics were prepared by melting-heat treatment technique. The effects of heat treatment processing on phase structure of the glass-ceramics were investigated. The leaching properties of the glass-ceramics were also evaluated by static leaching experiments (product consistency test, PCT). The results show that glass transformation temperature (T g ) and crystallization temperature of the glass-ceramics are about 580℃ and 740℃, respectively. CaTiO 3 phase forms easily when the glass-ceramics were prepared by two-step method, i.e. the glass was prepared first, and then it was heat-treated at the crystallization temperatures. 2M-zirconolite phase can be obtained by one-step method, i.e. the heat-treatment immediately followed by the melting process. In addition, the zirconolite crystals exhibit a dendritic shape. The normalized mass loss of B and Na in the glass-ceramics remains almost unchanged (about 1 mg/m 2 ) after 14 days, while the normalized mass loss of Nd reaches stable value (about 0.2 mg/m 2 ) after 28 days. The normalized mass loss of B, Na, and Nd in the glass-ceramics is an order of magnitude lower than that of borosilicate glasses, respectively. (authors)

  12. Systematic approach to preparing ceramic-glass composites with high translucency for dental restorations.

    Yoshimura, Humberto N; Chimanski, Afonso; Cesar, Paulo F

    2015-10-01

    Ceramic composites are promising materials for dental restorations. However, it is difficult to prepare highly translucent composites due to the light scattering that occurs in multiphase ceramics. The objective of this work was to verify the effectiveness of a systematic approach in designing specific glass compositions with target properties in order to prepare glass infiltrated ceramic composites with high translucency. First it was necessary to calculate from literature data the viscosity of glass at the infiltration temperature using the SciGlass software. Then, a glass composition was designed for targeted viscosity and refractive index. The glass of the system SiO2-B2O3-Al2O3-La2O3-TiO2 prepared by melting the oxide raw materials was spontaneously infiltrated into porous alumina preforms at 1200°C. The optical properties were evaluated using a refractometer and a spectrophotometer. The absorption and scattering coefficients were calculated using the Kubelka-Munk model. The light transmittance of prepared composite was significantly higher than a commercial ceramic-glass composite, due to the matching of glass and preform refractive indexes which decreased the scattering, and also to the decrease in absorption coefficient. The proposed systematic approach was efficient for development of glass infiltrated ceramic composites with high translucency, which benefits include the better aesthetic performance of the final prosthesis. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  13. Redox Control For Hanford HLW Feeds VSL-12R2530-1, REV 0

    Kruger, A. A.; Matlack, Keith S.; Pegg, Ian L.; Kot, Wing K.; Joseph, Innocent

    2012-01-01

    The principal objectives of this work were to investigate the effects of processing simulated Hanford HLW at the estimated maximum concentrations of nitrates and oxalates and to identify strategies to mitigate any processing issues resulting from high concentrations of nitrates and oxalates. This report provides results for a series of tests that were performed on the DM10 melter system with simulated C-106/AY-102 HLW. The tests employed simulated HLW feeds containing variable amounts of nitrates and waste organic compounds corresponding to maximum concentrations proj ected for Hanford HLW streams in order to determine their effects on glass production rate, processing characteristics, glass redox conditions, melt pool foaming, and the tendency to form secondary phases. Such melter tests provide information on key process factors such as feed processing behavior, dynamic effects during processing, processing rates, off-gas amounts and compositions, foaming control, etc., that cannot be reliably obtained from crucible melts

  14. Redox Control For Hanford HLW Feeds VSL-12R2530-1, REV 0

    Kruger, A. A. [Department of Energy, Office of River Protection, Richland, Washington (United States); Matlack, Keith S. [The Catholic University of America, Washington, DC (United States); Pegg, Ian L. [The Catholic University of America, Washington, DC (United States); Kot, Wing K. [The Catholic University of America, Washington, DC (United States); Joseph, Innocent [The Catholic University of America, Washington, DC (United States)

    2012-12-13

    The principal objectives of this work were to investigate the effects of processing simulated Hanford HLW at the estimated maximum concentrations of nitrates and oxalates and to identify strategies to mitigate any processing issues resulting from high concentrations of nitrates and oxalates. This report provides results for a series of tests that were performed on the DM10 melter system with simulated C-106/AY-102 HLW. The tests employed simulated HLW feeds containing variable amounts of nitrates and waste organic compounds corresponding to maximum concentrations proj ected for Hanford HLW streams in order to determine their effects on glass production rate, processing characteristics, glass redox conditions, melt pool foaming, and the tendency to form secondary phases. Such melter tests provide information on key process factors such as feed processing behavior, dynamic effects during processing, processing rates, off-gas amounts and compositions, foaming control, etc., that cannot be reliably obtained from crucible melts.

  15. Safety assessment of HLW geological disposal system

    Naito, Morimasa

    2006-01-01

    In accordance with the Japanese nuclear program, the liquid waste with a high level of radioactivity arising from reprocessing is solidified in a stable glass matrix (vitrification) in stainless steel fabrication containers. The vitrified waste is referred to as high-level radioactive waste (HLW), and is characterized by very high initial radioactivity which, even though it decreases with time, presents a potential long-term risk. It is therefore necessary to thoroughly manage HLW from human and his environment. After vitrification, HLW is stored for a period of 30 to 50 years to allow cooling, and finally disposed of in a stable geological environment at depths greater than 300 m below surface. The deep underground environment, in general, is considered to be stable over geological timescales compared with surface environment. By selecting an appropriate disposal site, therefore, it is considered to be feasible to isolate the waste in the repository from man and his environment until such time as radioactivity levels have decayed to insignificance. The concept of geological disposal in Japan is similar to that in other countries, being based on a multibarrier system which combines the natural geological environment with engineered barriers. It should be noted that geological disposal concept is based on a passive safety system that does not require any institutional control for assuring long term environmental safety. To demonstrate feasibility of safe HLW repository concept in Japan, following technical steps are essential. Selection of a geological environment which is sufficiently stable for disposal (site selection). Design and installation of the engineered barrier system in a stable geological environment (engineering measures). Confirmation of the safety of the constructed geological disposal system (safety assessment). For site selection, particular consideration is given to the long-term stability of the geological environment taking into account the fact

  16. Citrate increases glass transition temperature of vitrified sucrose preparations

    Kets, E.P.W.; Lipelaar, P.J.; Hoekstra, F.A.; Vromans, H.

    2004-01-01

    The aim of this study was to investigate the effect of sodium citrate on the properties of dried amorphous sucrose glasses. Addition of sodium citrate to a sucrose solution followed by freeze-drying or convective drying resulted in a glass transition temperature (T-g) that was higher than the

  17. Sodalite as a vehicle to increase Re retention in waste glass simulant during vitrification

    Luksic, Steven A., E-mail: steven.luksic@pnnl.gov; Riley, Brian J.; Parker, Kent E.; Hrma, Pavel

    2016-10-15

    Technetium (Tc) retention during Hanford waste vitrification can be increased if the volatility can be controlled. Incorporating Tc into a thermally stable mineral phase, such as sodalite, is one way to achieve increased retention. Here, rhenium (Re)-bearing sodalite was tested as a vehicle to transport perrhenate (ReO{sub 4}{sup −}), a nonradioactive surrogate for pertechnetate (TcO{sub 4}{sup −}), into high-level (HLW) and low-activity waste (LAW) glass simulants. After melting HLW and LAW simulant feeds, the retention of Re in the glass was measured and compared with the Re retention in glass prepared from a feed containing Re{sub 2}O{sub 7}. Phase analysis of sodalite in both these glasses across a profile of temperatures describes the durability of Re-sodalite during the feed-to-glass transition. The use of Re sodalite improved the Re retention by 21% for HLW glass and 85% for LAW glass, demonstrating the potential improvement in Tc-retention if TcO{sub 4}{sup −} were to be encapsulated in a Tc-sodalite prior to vitrification. - Highlights: • Re retention is improved by incorporation into sodalite structure. • LAW-type glass shows lower retention but larger improvement with Re-sodalite. • Sodalite is stable to higher temperatures in high-alumina glass melts.

  18. Development of the high-level waste high-temperature melter feed preparation flowsheet for vitrification process testing

    Seymour, R.G.

    1995-01-01

    High-level waste (HLW) feed preparation flowsheet development was initiated in fiscal year (FY) 1994 to evaluate alternative flowsheets for preparing melter feed for high-temperature melter (HTM) vitrification testing. Three flowsheets were proposed that might lead to increased processing capacity relative to the Hanford Waste Vitrification Plant (HWVP) and that were flexible enough to use with other HLW melter technologies. This document describes the decision path that led to the selection of flowsheets to be tested in the FY 1994 small-scale HTM tests. Feed preparation flowsheet development for the HLW HTM was based on the feed preparation flowsheet that was developed for the HWVP. This approach allowed the HLW program to build upon the extensive feed preparation flowsheet database developed under the HWVP Project. Primary adjustments to the HWVP flowsheet were to the acid adjustment and glass component additions. Developmental background regarding the individual features of the HLW feed preparation flowsheets is provided. Applicability of the HWVP flowsheet features to the new HLW vitrification mission is discussed. The proposed flowsheets were tested at the laboratory-scale at Pacific Northwest Laboratory. Based on the results of this testing and previously established criteria, a reductant-based flowsheet using glycolic acid and a nitric acid-based flowsheet were selected for the FY 1994 small-scale HTM testing

  19. PREPARATION AND CHARACTERIZATION OF POROUS WALLED HOLLOW GLASS MICROSPHERES

    Raszewski, F; Erich Hansen, E; Ray Schumacher, R; David Peeler, D

    2008-04-21

    Porous-walled hollow glass microspheres (PWHGMs) of a modified alkali borosilicate composition have been successfully fabricated by combining the technology of producing hollow glass microspheres (HGMs) with the knowledge associated with porous glasses. HGMs are first formed by a powder glass--flame process, which are then transformed to PWHGMs by heat treatment and subsequent treatment in acid. Pore diameter and pore volume are most influenced by heat treatment temperature. Pore diameter is increased by a factor of 10 when samples are heat treated prior to acid leaching; 100 {angstrom} in non-heat treated samples to 1000 {angstrom} in samples heat treated at 600 C for 8 hours. As heat treatment time is increased from 8 hours to 24 hours there is a slight shift increase in pore diameter and little or no change in pore volume.

  20. Thermal Conductivity of Foam Glasses Prepared using High Pressure Sintering

    Østergaard, Martin Bonderup; Petersen, Rasmus Rosenlund; König, Jakob

    The increasing focus on better building insulation is important to lower energy consumption. Development of new and improved insulation materials can contribute to solving this problem. Foam glass has a good insulating effect due to its large gas volume (porosity >90 %). It can be produced with o...... the thermal conductivity varies with gas composition. This allows us to determine the contribution of the gas and solid phase to the total thermal conductivity of a foam glass....

  1. Preparation of oxide glasses from metal alkoxides by sol-gel method

    Kamiya, K.; Yoko, T.; Sakka, S.

    1987-01-01

    An investigation is carried out on the types of siloxane polymers produced in the course of the hydrolysis of silicon tetraethoxide, as well as the preparation of oxide glasses from metal alkoxides by the sol-gel method.

  2. Counter current decantation washing of HLW sludge

    Brooke, J.N.; Peterson, R.A.

    1997-01-01

    The Savannah River Site (SRS) has 51 High Level Waste (HLW) tanks with typical dimensions 25.9 meters (85 feet) diameter and 10 meters (33 feet) high. Nearly 114 million liters (30 M gallons) of HLW waste is stored in these tanks in the form of insoluble solids called sludge, crystallized salt called salt cake, and salt solutions. This waste is being converted to waste forms stable for long term storage. In one of the processes, soluble salts are washed from HLW sludge in preparation for vitrification. At present, sludge is batch washed in a waste tank with one or no reuse of the wash water. Sodium hydroxide and sodium nitrite are added to the wash water for tank corrosion protection; the large volumes of spent wash water are recycled to the evaporator system; additional salt cake is produced; and sodium carbonate is formed in the washed sludge during storage by reaction with CO 2 from the air. High costs and operational concerns with the current washing process prompts DOE and WSRC to seek an improved washing method. A new method should take full advantage of the physical/chemical properties of sludge, experience from other technical disciplines, processing rate requirements, inherent process safety, and use of proven processes and equipment. Counter current solids washing is a common process in the minerals processing and chemical industries. Washing circuits can be designed using thickeners, filters or centrifuges. Realizing the special needs of nuclear work and the low processing rates required, a Counter Current Decantation (CCD) circuit is proposed using small thickeners and fluidic pumps

  3. Factors influencing the preparation of silver-coated glass frit with polyvinyl-pyrrolidone

    Xiang, Feng; Gan, Weiping

    2018-01-01

    In this work, a new electroless silver plating method for the synthesis of silver-coated glass frit composite powders with good morphology has been proposed and the polyvinyl-pyrrolidone (PVP) was used the activating agent. It was found that the weight ratio of PVP to glass frit affected the distribution and number of silver nanoparticles. Moreover, the loading capacity of the glass frit, the pH value and reaction temperature could influence the size of the silver nanoparticles and morphology of silver on the surface of glass frit. The as-prepared silver-coated glass frit was used to prepare a silver paste using an optimized process to form silver nanoparticles with uniform size and high density. The silver paste with silver-coated glass frit increased the photovoltaic conversion efficiency of silicon solar cells by 0.271% compared with the silver paste prepared with pure glass frit. The silver nanoparticles can promoted the precipitation of Ag crystallites on the silicon wafer. Therefore, the silver-coated glass frit can further optimize and enhance the electrical performance of solar cells.

  4. PREPARATION OF ZEOLITE X COATINGS ON SODA-LIME TYPE GLASS PLATES

    M. Tatlier

    Full Text Available Abstract The dissolution of glass in highly alkaline reaction mixtures and the impact of this phenomenon on zeolite coating formation were investigated. Coating samples were prepared and characterized by X-ray diffraction (XRD, field emission gun scanning electron microscopy (FEGSEM and thermogravimetry (TG. It was demonstrated that zeolite X coatings might be prepared on soda-lime glass. Glass dissolved to some degree, up to 2% of its original mass, in the reaction mixtures for the conditions investigated. This dissolution affected the zeolite synthesis taking place on the glass surface, resulting in phases different from those obtained on inert metal surfaces in some cases, especially for the use of reaction mixtures with relatively high Si/Al ratios. The percentage of dissolution of glass plates increased with their decreasing thickness, indicating a surface phenomenon for the dissolution. The stabilities of the coatings, which varied with the synthesis conditions, benefited from the addition of extra thin layers of polyacrylic acid.

  5. Preparation of Pb(Zr, Ti)O3 Thin Films on Glass Substrates

    Hioki, Tsuyoshi; Akiyama, Masahiko; Ueda, Tomomasa; Onozuka, Yutaka; Hara, Yujiro; Suzuki, Kouji

    2000-09-01

    Lead-zirconate-titanate (PZT) thin films were prepared on non-alkaline glass substrates widely used in liquid crystal display (LCD) devices, by plasma-assisted magnetron RF sputtering with an immersed coil. After preparation of the PZT thin film, the glass was available for use in LCD device processing. No mutual diffusion of the elements was recognized between the glass substrate and the bottom electrode. The PZT layer had a dense film structure with rectangular and columnar grains, and only its perovskite phase was crystalline. PZT thin films on a glass substrate had leakage current densities of about 10-8 A/cm2, acceptable hysteresis loop shapes with the remanent polarization (Pr) of 45 μC/cm2 and the coercive field (Ec) of 90 kV/cm. Ferroelectric properties on a glass substrate almost conform with those on a Si-based substrate.

  6. Preparation and properties of hollow glass microspheres for use in laser fusion experiments

    Campbell, J.H.; Grens, J.Z.; Poco, J.F.

    1983-11-01

    We review the preparation of high quality, hollow-glass microspheres for use in laser driven fusion experiments at LLNL. The primary focus of this paper is on the liquid-droplet method for making glass spheres, which has been in use at LLNL for over six years. We have combined the results from previous studies with our current results to present a detailed description of the preparation and the composition and physical properties of the glass microspheres. We also present a mathematical model that simulates the microsphere formation process. Examples are given of the application of the model to study the effects of various process parameters.

  7. Preparation and properties of hollow glass microspheres for use in laser fusion experiments

    Campbell, J.H.; Grens, J.Z.; Poco, J.F.

    1983-01-01

    We review the preparation of high quality, hollow-glass microspheres for use in laser driven fusion experiments at LLNL. The primary focus of this paper is on the liquid-droplet method for making glass spheres, which has been in use at LLNL for over six years. We have combined the results from previous studies with our current results to present a detailed description of the preparation and the composition and physical properties of the glass microspheres. We also present a mathematical model that simulates the microsphere formation process. Examples are given of the application of the model to study the effects of various process parameters

  8. Preparation and spectroscopic properties of Yb-doped and Yb-Al-codoped high silica glasses

    Qiao Yanbo; Wen Lei; Wu Botao; Ren Jinjun; Chen Danping; Qiu Jianrong

    2008-01-01

    Yb-doped and Yb-Al-codoped high silica glasses have been prepared by sintering nanoporous glasses. The absorption, fluorescent spectra and fluorescent lifetimes have been measured and the emission cross-section and minimum pump intensities were calculated. Codoping aluminum ions enhanced the fluorescence intensity of Yb-doped high silica glass obviously. The emission cross-sections of Yb-doped and Yb-Al-codoped high silica glasses were 0.65 and 0.82 pm 2 , respectively. The results show that Yb-Al-codoped high silica glass has better spectroscopic properties for a laser material. The study of high silica glass doped with ytterbium is helpful for its application in Yb laser systems, especially for high-power and high-repetition lasers

  9. HLW Tank Space Management, Final Report

    Sessions, J.

    1999-01-01

    The HLW Tank Space Management Team (SM Team) was chartered to select and recommend an HLW Tank Space Management Strategy (Strategy) for the HLW Management Division of Westinghouse Savannah River Co. (WSRC) until an alternative salt disposition process is operational. Because the alternative salt disposition process will not be available to remove soluble radionuclides in HLW until 2009, the selected Strategy must assure that it safely receives and stores HLW at least until 2009 while continuing to supply sludge slurry to the DWPF vitrification process

  10. Preparation and characterization of phosphate glasses containing titanium and vanadium

    Kaoua, S. [Laboratoire de Chimie du Solide, Faculte des Sciences Ain Chock, Casablanca (Morocco); Krimi, S. [Laboratoire de Chimie du Solide, Faculte des Sciences Ain Chock, Casablanca (Morocco)]. E-mail: krimisaida@yahoo.fr; El Jazouli, A. [Laboratoire de Chimie des Materiaux Solides, Faculte des Sciences Ben M' Sik, Casablanca (Morocco); Hlil, E.K. [Laboratoire de Cristallographie du CNRS, Grenoble (France)]. E-mail: hlil@grenoble.cnrs.fr; Waal, D. de [Department of Chemistry, University of Pretoria, 0002 Pretoria (South Africa)

    2007-02-21

    Na{sub 5-x}Ti{sub 1-x}V {sub x}(PO{sub 4}){sub 3} (0 {<=} x {<=} 1) phosphates glasses have been obtained in air by direct fusion of Na{sub 2}CO{sub 3}, TiO{sub 2}, V{sub 2}O{sub 5} and (NH{sub 4}){sub 2}HPO{sub 4}. Vitreous Na{sub 5}Ti(PO{sub 4}){sub 3} is colourless while the glasses containing vanadium are green, due to the reduction of V{sup 5+} to V{sup 4+}. Glass transition and crystallization temperatures (T {sub g}, T {sub c}) decrease when the amount of vanadium increases. EPR, Raman and UV-vis spectra have been investigated. The results are consistent with the presence of V{sup 4+} ions in distorted octahedra with very strong V-O bond.

  11. Suppressed beta relaxations and reduced heat capacity in ultrastable organic glasses prepared by physical vapor deposition

    Ediger, Mark

    Glasses play an important role in technology as a result of their macroscopic homogeneity (e.g., the clarity of window glass) and our ability to tune properties through composition changes. A problem with liquid-cooled glasses is that they exhibit marginal kinetic stability and slowly evolve towards lower energy glasses and crystalline states. In contrast, we have shown that physical vapor deposition can prepare glasses with very high kinetic stability. These materials have properties expected for ``million-year-old'' glasses, including high density, low enthalpy, and high mechanical moduli. We have used nanocalorimetry to show that these high stability glasses have lower heat capacities than liquid-cooled glasses for a number of molecular systems. Dielectric relaxation has been used to show that the beta relaxation can be suppressed by nearly a factor of four in vapor-deposited toluene glasses, indicating a very tight packing environment. Consistent with this view, computer simulations of high stability glasses indicate reduced Debye-Waller factors. These high stability materials raise interesting questions about the limiting properties of amorphous packing arrangements.

  12. Preparation and investigation of Ge-S-I glasses for infrared fiber optics

    Velmuzhov, A. P.; Sukhanov, M. V.; Plekhovich, A. D.; Snopatin, G. E.; Churbanov, M. F.; Iskhakova, L. D.; Ermakov, R. P.; Kotereva, T. V.; Shiryaev, V. S.

    2016-02-01

    Glass samples of [GeSx]90I10 (x = 1.5, 1.7, 2.0, 2.3, 2.45, 2.6) compositions were prepared, and some their thermal, optical properties as well as tendency to crystallization were investigated. The compositional dependences of glass transition temperature, volume fraction of crystallized phase and activation energy of glass formation (Eg) have nonmonotonic character with a maximum for [GeS2.0]90I10 glass. Glasses of 85.8GeS2-14.2GeI4 and [GeS1.5]90I10 compositions are identified as promising for preparation of optical fiber. For the first time, Ge-S-I glass fibers were produced. Minimum optical losses in 85.8GeS2-14.2GeI4 glass fiber were 2.7 dB/m at a wavelength of 5.1 μm, and that in [GeS1.5]90I10 glass fiber were 14.5 dB/m at 5.5 μm.

  13. Comparison of optical properties of Eu3+ ions in the silica gel glasses obtained by different preparation techniques

    Legendziewicz, J.; Sokolnicki, J.; Keller, B.; Borzechowska, M.; Strek, W.

    1996-01-01

    Silica-gel glasses doped with Eu 3+ ions were obtained by different preparation techniques. The absorption, emission and excitation spectra of the obtained glasses were measured in the range of 77-300 K. The energy levels diagrams of Eu 3+ ions were derived. An intensity analysis of f-f transitions was performed. In particular, polymeric structure behaviour of europium compounds entrapped in silica gel glasses was temperature controlled during the preparation of glasses. Their optical properties were investigated. (author)

  14. RECENT PROCESS IMPROVEMENTS TO INCREASE HLW THROUGHPUT AT THE DWPF

    Herman, C

    2007-01-01

    The Savannah River Site's (SRS) Defense Waste Processing Facility (DWPF), the world's largest operating high level waste (HLW) vitrification plant, began stabilizing about 35 million gallons of SRS liquid radioactive waste by-product in 1996. The DWPF has since filled over 2000 canisters with about 4000 pounds of radioactive glass in each canister. In the past few years there have been several process and equipment improvements at the DWPF to increase the rate at which the waste can be stabilized. These improvements have either directly increased waste processing rates or have desensitized the process and therefore minimized process upsets and thus downtime. These improvements, which include glass former optimization, increased waste loading of the glass, the melter heated bellows liner, and glass surge protection software, will be discussed in this paper

  15. Preparation method and thermal properties of samarium and europium-doped alumino-phosphate glasses

    Sava, B.A., E-mail: savabogdanalexandru@yahoo.com [National Institute of Research and Development for Optoelectronics, Department for Optospintronics, 409 Atomistilor Street, P.O. Box MG – 5, RO-77125 Magurele (Romania); Elisa, M., E-mail: astatin18@yahoo.com [National Institute of Research and Development for Optoelectronics, Department for Optospintronics, 409 Atomistilor Street, P.O. Box MG – 5, RO-77125 Magurele (Romania); Boroica, L., E-mail: boroica_lucica@yahoo.com [National Institute for Lasers, Plasma and Radiation Physics, 77125 Magurele (Romania); Monteiro, R.C.C., E-mail: rcm@fct.unl.pt [Center of Materials Research/Institute for Nanostructures, Nanomodelling and Nanofabrication, (CENIMAT/I3N), Department of Materials Sciences, Faculty of Sciences and Technology, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)

    2013-12-01

    Highlights: • Improved preparation method of rare-earth-doped phosphate glasses was done. • Working and annealing temperatures were lower than for undoped phosphate glass. • Doped glass viscosity is also lower and has quasi-linear variation with temperature. • Exothermic peak appears at about 555 °C and 685 °C, due to devitrification in glass. -- Abstract: The present work investigates alumino-phosphate glasses from Li{sub 2}O–BaO–Al{sub 2}O{sub 3}–La{sub 2}O{sub 3}–P{sub 2}O{sub 5} system containing Sm{sup 3+} and Eu{sup 3+} ions, prepared by two different ways: a wet raw materials mixing route followed by evaporation and melt-quenching, and by remelting of shards. The linear thermal expansion coefficient measured by dilatometry is identical for both rare-earth-doped phosphate glasses. Comparatively to undoped phosphate glass the linear thermal expansion coefficient increases with 2 × 10{sup −7} K{sup −1} when dopants are added. The characteristic temperatures very slowly decrease but can be considered constant with atomic weight, atomic number and f electrons number of the doping ions in the case of T{sub g} (vitreous transition temperature) and T{sub sr} (high annealing temperature) but slowly increase in the case of T{sub ir} (low annealing temperature–strain point) and very slowly increase, being practically constant in the case of T{sub D} (dilatometric softening temperature). Comparatively to undoped phosphate glass the characteristic temperatures of Sm and Eu-doped glasses present lower values. The higher values of electrical conductance for both doped glasses, comparatively to usual soda-lime-silicate glass, indicate a slightly reduced stability against water. The viscosity measurements, showed a quasi-linear variation with temperature the mean square deviation (R{sup 2}) being ranged between 0.872% and 0.996%. The viscosity of doped glasses comparatively to the undoped one is lower at the same temperature. Thermogravimetric

  16. Enzyme-Free Electrochemical Glucose Sensors Prepared by Dealloying Pd-Ni-P Metallic Glasses

    Yuqiao Zeng

    2014-01-01

    Full Text Available We report the formation of enzyme-free electrochemical glucose sensors by electrochemical dealloying palladium-containing Pd-Ni-P metallic glasses. When metallic glasses with different Pd contents are used as the dealloying precursor alloys, palladium-based nanoporous metals with different ligament and pore sizes can be obtained. The chemical compositions of the nanoporous metals also vary according to the different precursor compositions. All the as-obtained nanoporous metals exhibit electrochemical catalytic activity towards the oxidation of d-glucose, indicating that the nanoporous metals prepared by dealloying the Pd-Ni-P metallic glasses are promising materials for enzyme-free electrochemical glucose sensor.

  17. Porous glass with high silica content for nuclear waste storage : preparation, characterization and leaching

    Aegerter, M.A.; Santos, D.I. dos; Ventura, P.C.S.

    1984-01-01

    Aqueous solutions simulating radioactive nuclear wastes (like Savanah River Laboratory) were incorporated in porous glass matrix with high silica content prepared by decomposition of borosilicate glass like Na 2 O - B 2 O 3 - SiO 2 . After sintering, the samples were submitted, during 28 days, to standard leaching tests MCC1, MCC5 (Soxhlet) and stagnating. The total weight loss, ph, as well as the integral and differential leaching rates and the accumulated concentrations in the leach of Si, Na, B, Ca, Mn, Al, Fe and Ni. The results are compared with the results from reference borosilicate glass, made by fusion, ceramic, synroc, concrets, etc... (E.G.) [pt

  18. Silicate glasses

    Lutze, W.

    1988-01-01

    Vitrification of liquid high-level radioactive wastes has received the greatest attention, world-wide, compared to any other HLW solidification process. The waste form is a borosilicate-based glass. The production of phosphate-based glass has been abandoned in the western world. Only in the Soviet Union are phosphate-based glasses still being developed. Vitrification techniques, equipment and processes and their remote operation have been developed and studied for almost thirty years and have reached a high degree of technical maturity. Industrial demonstration of the vitrification process has been in progress since 1978. This chapter is a survey of world-wide research and development efforts in nuclear waste glasses and its production technology. The principal glasses considered are silicate glasses which contain boron, i.e., borosilicate glasses

  19. Preparation of carbon nanotubes/epoxy resin composites by using hollow glass beads as the carrier

    Wu, X.F.; Zhao, Y.K.; Zhang, D.; Chen, T.B.; Ma, L.Y.

    2012-01-01

    Hollow glass beads had been utilized as the carrier to assist dispersion of carbon nanotubes in epoxy resin. Hollow glass beads were firstly aminated with gamma-aminopropyl-triethoxysilane, sencondly reacted with carboxyl-functionalized carbon nanotubes via an amidation reaction and susequently mixed with epoxy resin and hardener. The experimental results showed that carbon nanotubes could be loaded on the surfaces of hollow glass beads and approximately a monolayer of carbon nanotubes was formed when the weight ratio of hollow glass beads to carbon nanotubes was 100:5. Moreover, the dispersity of carbon nanotubes in the matrix was improved as compared to the control samples prepared by using a conventional mixing method. (author)

  20. HLW Melter Control Strategy Without Visual Feedback VSL-12R2500-1 Rev 0

    Kruger, A A. [Department of Energy, Office of River Protection, Richland, Washington (United States); Joseph, Innocent [The Catholic University of America, Washington, DC (United States); Matlack, Keith S. [The Catholic University of America, Washington, DC (United States); Callow, Richard A. [The Catholic University of America, Washington, DC (United States); Abramowitz, Howard [The Catholic University of America, Washington, DC (United States); Pegg, Ian L. [The Catholic University of America, Washington, DC (United States); Brandys, Marek [The Catholic University of America, Washington, DC (United States); Kot, Wing K. [The Catholic University of America, Washington, DC (United States)

    2012-11-13

    Plans for the treatment of high level waste (HL W) at the Hanford Tank Waste Treatment and Immobilization Plant (WTP) are based upon the inventory of the tank wastes, the anticipated performance of the pretreatment processes, and current understanding of the capability of the borosilicate glass waste form [I]. The WTP HLW melter design, unlike earlier DOE melter designs, incorporates an active glass bubbler system. The bubblers create active glass pool convection and thereby improve heat and mass transfer and increase glass melting rates. The WTP HLW melter has a glass surface area of 3.75 m{sup 2} and depth of ~ 1.1 m. The two melters in the HLW facility together are designed to produce up to 7.5 MT of glass per day at 100% availability. Further increases in HL W waste processing rates can potentially be achieved by increasing the melter operating temperature above 1150°C and by increasing the waste loading in the glass product. Increasing the waste loading also has the added benefit of decreasing the number of canisters for storage.

  1. HLW Melter Control Strategy Without Visual Feedback VSL-12R2500-1 Rev 0

    Kruger, A A.; Joseph, Innocent; Matlack, Keith S.; Callow, Richard A.; Abramowitz, Howard; Pegg, Ian L.; Brandys, Marek; Kot, Wing K.

    2012-01-01

    Plans for the treatment of high level waste (HL W) at the Hanford Tank Waste Treatment and Immobilization Plant (WTP) are based upon the inventory of the tank wastes, the anticipated performance of the pretreatment processes, and current understanding of the capability of the borosilicate glass waste form [I]. The WTP HLW melter design, unlike earlier DOE melter designs, incorporates an active glass bubbler system. The bubblers create active glass pool convection and thereby improve heat and mass transfer and increase glass melting rates. The WTP HLW melter has a glass surface area of 3.75 m 2 and depth of ∼ 1.1 m. The two melters in the HLW facility together are designed to produce up to 7.5 MT of glass per day at 100% availability. Further increases in HL W waste processing rates can potentially be achieved by increasing the melter operating temperature above 1150°C and by increasing the waste loading in the glass product. Increasing the waste loading also has the added benefit of decreasing the number of canisters for storage

  2. 12 Flasktransport of vitrified High Level Waste (HLW)

    Verdier, A.; Lancelot, J. [COGEMA Logistics (AREVA Group) (France); Gisbertz, A.; Graf, W. [GNS (Germany); Bartagnon, O. [COGEMA (AREVA Group) (France)

    2004-07-01

    The return of HLW to Germany has started in 1996 with the first attribution of 28 glass canisters to German utilities by COGEMA. After several transports comprising 1, 2 and 6 flasks per shipment German and French Authorities requested to transport 12 flasks in a single shipment. The first of these 12-flask-transports was performed with the type CASTOR {sup registered} HAW 20/28 CG flask in 2002 and the second followed in 2003. COGEMA LOGISTICS is responsible for the overall transport assigned by GNS (Gesellschaft fuer Nuklear-Service mbH) being itself entrusted by the German utilities with the return of reprocessing residues.

  3. 12 Flasktransport of vitrified High Level Waste (HLW)

    Verdier, A.; Lancelot, J.; Gisbertz, A.; Graf, W.; Bartagnon, O.

    2004-01-01

    The return of HLW to Germany has started in 1996 with the first attribution of 28 glass canisters to German utilities by COGEMA. After several transports comprising 1, 2 and 6 flasks per shipment German and French Authorities requested to transport 12 flasks in a single shipment. The first of these 12-flask-transports was performed with the type CASTOR registered HAW 20/28 CG flask in 2002 and the second followed in 2003. COGEMA LOGISTICS is responsible for the overall transport assigned by GNS (Gesellschaft fuer Nuklear-Service mbH) being itself entrusted by the German utilities with the return of reprocessing residues

  4. Preparation and bioactive properties of nano bioactive glass and segmented polyurethane composites.

    Aguilar-Pérez, Fernando J; Vargas-Coronado, Rossana F; Cervantes-Uc, Jose M; Cauich-Rodríguez, Juan V; Covarrubias, Cristian; Pedram-Yazdani, Merhdad

    2016-04-01

    Composites of glutamine-based segmented polyurethanes with 5 to 25 wt.% bioactive glass nanoparticles were prepared, characterized, and their mineralization potential was evaluated in simulated body fluid. Biocompatibility with dental pulp stem cells was assessed by MTS to an extended range of compositions (1 to 25 wt.% of bioactive glass nanoparticles). Physicochemical characterization showed that composites retained many of the matrix properties, i.e. those corresponding to semicrystalline elastomeric polymers as they exhibited a glass transition temperature (Tg) between -41 and -36℃ and a melting temperature (Tm) between 46 and 49℃ in agreement with X-ray reflections at 23.6° and 21.3°. However, with bioactive glass nanoparticles addition, tensile strength and strain were reduced from 22.2 to 12.2 MPa and 667.2 to 457.8%, respectively with 25 wt.% of bioactive glass nanoparticles. Although Fourier transform infrared spectroscopy did not show evidence of mineralization after conditioning of these composites in simulated body fluid, X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray microanalysis showed the formation of an apatite layer on the surface which increased with higher bioactive glass concentrations and longer conditioning time. Dental pulp stem cells proliferation at day 5 was improved in bioactive glass nanoparticles composites containing lower amounts of the filler (1-2.5 wt.%) but it was compromised at day 9 in composites containing high contents of nBG (5, 15, 25 wt.%). However, Runx2 gene expression was particularly upregulated for the dental pulp stem cells cultured with composites loaded with 15 and 25 wt.% of bioactive glass nanoparticles. In conclusion, low content bioactive glass nanoparticles and segmented polyurethanes composites deserve further investigation for applications such as guided bone regeneration membranes, where osteoconductivity is desirable but not a demanding mechanical performance. © The

  5. Hysteresis losses in iron oxide nanoparticles prepared by glass crystallization or wet chemical precipitation

    Mueller, Robert; Dutz, Silvio; Hergt, Rudolf; Schmidt, Christopher; Steinmetz, Hanna; Zeisberger, Matthias; Gawalek, Wolfgang

    2007-01-01

    Ferrofluids were prepared from glass crystallized as well as wet precipitated iron oxide particles. Comparing hysteresis losses versus applied field amplitude from particles in immobilized state (powder) and in fluid state (ferrofluid) shows in some cases anomalous large losses at low magnetic fields. The influence of texture on the losses was investigated

  6. Effect of Feed Melting, Temperature History and Minor Component Addition on Spinel Crystallization in High-Level Waste Glass

    Izak, Pavel; Hrma, Pavel R.; Arey, Bruce W.; Plaisted, Trevor J.

    2001-01-01

    This study was undertaken to help design mathematical models for high-level waste (HLW) glass melter that simulate spinel behavior in molten glass. Spinel, (Fe,Ni,Mn) (Fe,Cr)2O4, is the primary solid phase that precipitates from HLW glasses containing Fe and Ni in sufficient concentrations. Spinel crystallization affects the anticipated cost and risk of HLW vitrification. To study melting reactions, we used simulated HLW feed, prepared with co-precipitated Fe, Ni, Cr, and Mn hydroxides. Feed samples were heated up at a temperature-increase rate (4C/min) close to that which the feed experiences in the HLW glass melter. The decomposition, melting, and dissolution of feed components (such as nitrates, carbonates, and silica) and the formation of intermediate crystalline phases (spinel, sodalite (Na8(AlSiO4)6(NO2)2), and Zr-containing minerals) were characterized using evolved gas analysis, volume-expansion measurement, optical microscope, scanning electron microscope, thermogravimetric analysis, differential scanning calorimetry, and X-ray diffraction. Nitrates and quartz, the major feed components, converted to a glass-forming melt by 880C. A chromium-free spinel formed in the nitrate melt starting from 520C and Sodalite, a transient product of corundum dissolution, appeared above 600C and eventually dissolved in glass. To investigate the effects of temperature history and minor components (Ru,Ag, and Cu) on the dissolution and growth of spinel crystals, samples were heated up to temperatures above liquidus temperature (TL), then subjected to different temperature histories, and analyzed. The results show that spinel mass fraction, crystals composition, and crystal size depend on the chemical and physical makeup of the feed and temperature history

  7. INTEGRATED DM 1200 MELTER TESTING OF HLW C-106/AY-102 COMPOSITION USING BUBBLERS VSL-03R3800-1 REV 0 9/15/03

    KRUGER AA; MATLACK KS; GONG W; BARDAKCI T; D' ANGELO NA; KOT WK; PEGG IL

    2011-12-29

    This report documents melter and off-gas performance results obtained on the DM1200 HLW Pilot Melter during processing of simulated HLW C-106/AY-102 feed. The principal objectives of the DM1200 melter testing were to determine the achievable glass production rates for simulated HLW C-106/AY-102 feed; determine the effect of bubbling rate on production rate; characterize melter off-gas emissions; characterize the performance of the prototypical off-gas system components as well as their integrated performance; characterize the feed, glass product, and off-gas effluents; and to perform pre- and post test inspections of system components.

  8. Integrated DM 1200 Melter Testing Of HLW C-106/AY-102 Composition Using Bubblers VSL-03R3800-1, Rev. 0, 9/15/03

    Kruger, A.A.; Matlack, K.S.; Kot, W.K.; Bardakci, T.; Gong, W.; D'Angelo, N.A.; Pegg, I.L.

    2011-01-01

    This report documents melter and off-gas performance results obtained on the DM1200 HLW Pilot Melter during processing of simulated HLW C-106/AY-102 feed. The principal objectives of the DM1200 melter testing were to determine the achievable glass production rates for simulated HLW C-106/AY-102 feed; determine the effect of bubbling rate on production rate; characterize melter off-gas emissions; characterize the performance of the prototypical off-gas system components as well as their integrated performance; characterize the feed, glass product, and off-gas effluents; and to perform pre- and post test inspections of system components.

  9. Preparation of durable hydrophobic cellulose fabric from water glass and mixed organosilanes

    Shang, Song-Min; Li, Zhengxiong; Xing, Yanjun; Xin, John H.; Tao, Xiao-Ming

    2010-12-01

    Durable superhydrophobic cellulose fabric was prepared from water glass and n-octadecyltriethoxysilane (ODTES) with 3-glycidyloxypropyltrimethoxysilane (GPTMS) as crosslinker by sol-gel method. The result showed that the addition of GPTMS could result in a better fixation of silica coating from water glass on cellulose fabric. The silanization of hydrolyzed ODTES at different temperatures and times was studied and optimized. The results showed that silanization time was more important than temperature in forming durable hydrophobic surface. The durability of superhydrophobicity treatment was analyzed by XPS. As a result, the superhydrophobic cotton treated under the optimal condition still remained hydrophobic properties after 50 washing cycles.

  10. Formulation of special glass frit and its use for decontamination of Joule melter employed for vitrification of high level and radioactive liquid waste

    Valsala, T.P.; Mishra, P.K.; Thakur, D.A.; Ghongane, D.E.; Jayan, R.V.; Dani, U.; Sonavane, M.S.; Kulkarni, Y.

    2012-01-01

    Advanced vitrification system at TWMP Tarapur was used for successful vitrification of large volume of HLW stored in waste tank farm. After completion of the operational life of the joule melter, dismantling was planned. Prior to the dismantling, the hold up inventory of active glass product from the melter was flushed out using specially formulated inactive glass frit to reduce the air activity buildup in the cell during dismantling operations. The properties of the special glass frit prepared are comparable with that of the regular product glass. More than 94% of holdup activity was flushed out from the joule melter prior to the dismantling of the melter. (author)

  11. Preparation and Dynamic Mechanical Properties at Elevated Temperatures of a Tungsten/Glass Composite

    Gao, Chong; Wang, Yingchun; Ma, Xueya; Liu, Keyi; Wang, Yubing; Li, Shukui; Cheng, Xingwang

    2018-03-01

    Experiments were conducted to prepare a borosilicate glass matrix composite containing 50 vol.% tungsten and examine its dynamic compressive behavior at elevated temperatures in the range of 450-775 °C. The results show that the homogenous microstructure of the tungsten/glass composite with relative density of 97% can be obtained by hot-pressing sintering at 800 °C for 1 h under pressure of 30 MPa. Dynamic compressive testing was carried out by a separate Hopkinson pressure bar system with a synchronous device. The results show that the peak stress decreases and the composite transforms from brittle to ductile in nature with testing temperature increasing from 450 to 750 °C. The brittle-ductile transition temperature is about 500 °C. Over 775 °C, the composite loses load-bearing capacity totally because of the excessive softening of the glass phase. In addition, the deformation and failure mechanism were analyzed.

  12. Judd-Ofelt Analysis of Dy3+-Activated Aluminosilicate Glasses Prepared by Sol-Gel Method

    Sengthong, Buonyavong; Van Tuyen, Ho; An, Nguyen Thi Thai; Van Do, Phan; Hai, Nguyen Thi Quy; Chau, Pham Thi Minh; Quang, Vu Xuan

    2018-04-01

    Aluminosilicate (AS) glasses doped with different Dy3+ concentrations were synthesized via sol-gel method. Absorption, photoluminescence spectra and lifetime of this material have been studied. From analytical results of absorption spectra, the Judd-Ofelt (JO) parameters of prepared samples have been determined. These JO parameters combined with photoluminescence spectra have been used to evaluate transition probabilities ( A R), branching ratios ( β) and the calculated oscillator strengths of AS:Dy3+ glasses. The radiative branching ratio of 4F9/2 → 6H13/2 transition has a minimum value at 62.2% for β R which predicts that this transition in AS:Dy3+ glasses can give rise to lasing action. JO parameters show that the Ω2 increases with the increasing of Dy3+ ion concentration due to the increased polarizability of the average coordination medium and decreased average symmetry.

  13. Preparation of hollow hydroxyapatite microspheres by the conversion of borate glass at near room temperature

    Yao, Aihua; Ai, Fanrong; Liu, Xin; Wang, Deping; Huang, Wenhai; Xu, Wei

    2010-01-01

    Hollow hydroxyapatite microspheres, consisting of a hollow core and a porous shell, were prepared by converting Li 2 O-CaO-B 2 O 3 glass microspheres in dilute phosphate solution at 37 o C. The results confirmed that Li 2 O-CaO-B 2 O 3 glass was transformed to hydroxyapatite without changing the external shape and dimension of the original glass object. Scanning electron microscopy images showed the shell wall of the microsphere was built from hydroxyapatite particles, and these particles spontaneously align with one another to form a porous sphere with an interior cavity. Increase in phosphate concentration resulted in an increase in the reaction rate, which in turn had an effect on shell wall structure of the hollow hydroxyapatite microsphere. For the Li 2 O-CaO-B 2 O 3 glass microspheres reacted in low-concentration K 2 HPO 4 solution, lower reaction rate and a multilayered microstructure were observed. On the other hand, the glass microspheres reacted in higher phosphate solution converted more rapidly and produced a single hydroxyapatite layer. Furthermore, the mechanism of forming hydroxyapatite hollow microsphere was described.

  14. Preparation, thermal stability, and magnetic properties of Fe-Zr-Mo-W-B bulk metallic glass

    Liu, D.Y.; Sun, W.S.; Wang, A.M.; Zhang, H.F.; Hu, Z.Q.

    2004-01-01

    A bulk metallic glass (BMG) cylinder of Fe 60 Co 8 Zr 10 Mo 5 W 2 B 15 with a diameter of 1.5 mm was prepared by copper mould casting of industrial raw materials. The amorphous state and the crystallization behavior were investigated by X-ray diffraction (XRD). The thermal stability parameters, such as glass transition temperature (T g ), crystallization temperature (T x ), supercooled liquid region (ΔT x ) between T g and T x , and reduced glass transition temperature T rg (T g /T m ) were measured by differential scanning calorimetry (DSC) to be 891, 950, 59 K, and 0.62, respectively. The crystallization process took place through a single stage, and involved crystallization of the phases α-Fe, ZrFe 2 , Fe 3 B, MoB 2 , Mo 2 FeB 2 , and an unknown phase, as determined by X-ray analysis of the sample annealed for 1.5 ks at 1023 K, 50 K above the DSC peak temperature of crystallization. Moessbauer spectroscopy was studied for this alloy. The spectra exhibit a broadened and asymmetric doublet-like structure that indicated paramagnetic behavior and a fully amorphous structure. α-Fe was found in the amorphous matrix for a cylinder with a diameter of 2.5 mm. The success of synthesis of the Fe-based bulk metallic glass from industrial materials is important for the future progress in research and practical application of new bulk metallic glasses

  15. Examining the role of canister cooling conditions on the formation of nepheline from nuclear waste glasses

    Christian, J. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-09-01

    Nepheline (NaAlSiO₄) crystals can form during slow cooling of high-level waste (HLW) glass after it has been poured into a waste canister. Formation of these crystals can adversely affect the chemical durability of the glass. The tendency for nepheline crystallization to form in a HLW glass increases with increasing concentrations of Al₂O₃ and Na₂O.

  16. Glasses

    Dyre, Jeppe

    2004-01-01

    The temperature dependence of the viscosity of most glassforming liquids is known to depart significantly from the classical Arrhenius behaviour of simple fluids. The discovery of an unexpected correlation between the extent of this departure and the Poisson ratio of the resulting glass could lead...... to new understanding of glass ageing and viscous liquid dynamics....

  17. Quantitative morphological and compositional evaluation of laboratory prepared aluminoborosilicate glass surfaces

    Gong, Yuxuan, E-mail: yg4@alfred.edu; Wren, Anthony W.; Mellott, Nathan P.

    2015-01-01

    Graphical abstract: - Highlights: • Aluminoborosilicate glass surfaces were prepared through both melting and polishing/etching and the surface composition and morphology were quantified as a function of processing method. • Glass surface morphology was quantified using PSD analysis, followed by both fractal and ABC model fitting, resulting in a comprehensive description of the spatial distribution of roughness. • All melt surfaces showed a depletion in Na, Ca, and B with respect to the bulk composition. Polished/etched surfaces showed a depletion in Na, B, and Al with respect to the bulk composition. • It was found that increasing heat treatment temperature of melt surfaces lead to a decrease in equivalent roughness and an increased spatial homogeneity of roughness while etching of polished ISG glass surfaces decreases the roughness and spatial distribution homogeneity of roughness. - Abstract: Surface finishing techniques including polishing, etching and heat treatment can modify the topography and the surface chemical composition of glasses. It is widely acknowledged that atomic force microscopy (AFM) can be used to quantify the morphology of surfaces, providing various parameters including average, peak-to-valley, and apparent root-mean-square roughness. Furthermore advanced power spectral density (PSD) analysis of AFM-derived surface profiles offers quantification of the spatial homogeneity of roughness values along different wavelengths, resulting in parameters including equivalent RMS, Hurst exponent, and fractal dimension. Outermost surface (∼8 nm) chemical composition can be quantitatively measured by X-ray photoelectron spectroscopy. In this paper, we first developed a series of surface finishing methods for an aluminoborosilicate glass system by polishing, etching or heat treatment. The chemical composition and environment of prepared glass surfaces were quantified by XPS and topographical analysis was carried out by fractal and k

  18. Support for HLW Direct Feed - Phase 2, VSL-15R3440-1

    Matlack, K. S. [The Catholic Univ. of America, Washington, DC (United States); Pegg, I. [The Catholic Univ. of America, Washington, DC (United States); Joseph, I. [EnergySolutions, Columbia, MD (United States); Kot, W. K. [The Catholic Univ. of America, Washington, DC (United States)

    2017-03-20

    This report describes work performed to develop and test new glass and feed formulations originating from a potential flow-sheet for the direct vitrification of High Level Waste (HLW) with minimal or no pretreatment. In the HLW direct feed option that is under consideration for early operations at the Hanford Tank Waste Treatment and Immobilization Plant (WTP), the pretreatment facility would be bypassed in order to support an earlier start-up of the vitrification facility. For HLW, this would mean that the ultrafiltration and caustic leaching operations that would otherwise have been performed in the pretreatment facility would either not be performed or would be replaced by an interim pretreatment function (in-tank leaching and settling, for example). These changes would likely affect glass formulations and waste loadings and have impacts on the downstream vitrification operations. Modification of the pretreatment process may result in: (i) Higher aluminum contents if caustic leaching is not performed; (ii) Higher chromium contents if oxidative leaching is not performed; (iii) A higher fraction of supernate in the HLW feed resulting from the lower efficiency of in-tank washing; and (iv) A higher water content due to the likely lower effectiveness of in-tank settling compared to ultrafiltration. The HLW direct feed option has also been proposed as a potential route for treating HLW streams that contain the highest concentrations of fast-settling plutoniumcontaining particles, thereby avoiding some of the potential issues associated with such particles in the WTP Pretreatment facility [1]. In response, the work presented herein focuses on the impacts of increased supernate and water content on wastes from one of the candidate source tanks for the direct feed option that is high in plutonium.

  19. Korean Reference HLW Disposal System

    Choi, Heui Joo; Lee, J. Y.; Kim, S. S. (and others)

    2008-03-15

    This report outlines the results related to the development of Korean Reference Disposal System for High-level radioactive wastes. The research has been supported around for 10 years through a long-term research plan by MOST. The reference disposal method was selected via the first stage of the research during which the technical guidelines for the geological disposal of HLW were determined too. At the second stage of the research, the conceptual design of the reference disposal system was made. For this purpose the characteristics of the reference spent fuels from PWR and CANDU reactors were specified, and the material and specifications of the canisters were determined in term of structural analysis and manufacturing capability in Korea. Also, the mechanical and chemical characteristics of the domestic Ca-bentonite were analyzed in order to supply the basic design parameters of the buffer. Based on these parameters the thermal and mechanical analysis of the near-field was carried out. Thermal-Hydraulic-Mechanical behavior of the disposal system was analyzed. The reference disposal system was proposed through the second year research. At the final third stage of the research, the Korean Reference disposal System including the engineered barrier, surface facilities, and underground facilities was proposed through the performance analysis of the disposal system.

  20. A dose of HLW reality

    Payne, J.

    1993-01-01

    What many people were sure they knew, and some others were fairly confident they knew, was acknowledged by the US Department of Energy in December: A monitored retrievable storage (MRS) facility will not be ready to accept spent fuel by January 31, 1998. A dose of reality has thus been added to the US high-level radioactive waste scene. Perhaps as important as the new reality is the practical, businesslike nature of the DOE's plan. The Department's proposal has the quality of a plan aimed at genuinely solving a problem rather just going through the motions. (In contrast, some readers are familiar with New York State's procedures for siting and licensing a low-level waste facility - procedures so labyrinthine that they are much more likely to protect political careers in that state than they are to achieve an LLW site). The DOE has received a lot of criticism - some justified, some not - about its handling of the HLW program. In this instance, it is proposing what many in the industry might have recommended: Make available storage capacity for spent nuclear fuel at existing federal government sites

  1. Crystallization characteristics of iron-rich glass ceramics prepared from nickel slag and blast furnace slag

    Wang, Zhong-Jie; Ni, Wen; Li, Ke-Qing; Huang, Xiao-Yan; Zhu, Li-Ping

    2011-08-01

    The crystallization process of iron-rich glass-ceramics prepared from the mixture of nickel slag (NS) and blast furnace slag (BFS) with a small amount of quartz sand was investigated. A modified melting method which was more energy-saving than the traditional methods was used to control the crystallization process. The results show that the iron-rich system has much lower melting temperature, glass transition temperature ( T g), and glass crystallization temperature ( T c), which can result in a further energy-saving process. The results also show that the system has a quick but controllable crystallization process with its peak crystallization temperature at 918°C. The crystallization of augite crystals begins from the edge of the sample and invades into the whole sample. The crystallization process can be completed in a few minutes. A distinct boundary between the crystallized part and the non-crystallized part exists during the process. In the non-crystallized part showing a black colour, some sphere-shaped augite crystals already exist in the glass matrix before samples are heated to T c. In the crystallized part showing a khaki colour, a compact structure is formed by augite crystals.

  2. Preparation of glass-forming materials from granulated blast furnace slag

    Alonso, M.; Sáinz, E.; Lopez, F. A.

    1996-10-01

    Glass precursor materials, to be used for the vitrification of hazardous wastes, have been prepared from blast furnace slag powder through a sol-gel route. The slag is initially reacted with a mixture of alcohol (ethanol or methanol) and mineral acid (HNO3 or H2SO4) to give a sol principally consisting of Si, Ca, Al, and Mg alkoxides. Gelation is carried out with variable amounts of either ammonia or water. The gelation rate can be made as fast as desired by adding excess hydrolizing agent or else by distilling the excess alcohol out of the alkoxide solution. The resulting gel is first dried at low temperature and ground. The powder thus obtained is then heat treated at several temperatures. The intermediate and final materials are characterized by thermal analysis, infrared (IR) spectroscopy, X-ray diffraction, scanning electron microscopy (SEM), and chemical analysis. From the results, the operating conditions yielding a variety of glass precursors differing in their composition are established. The method, in comparison with direct vitrification of slag, presents a number of advantages: (1) the glass precursor obtained devitrifies at higher temperatures; (2) it enables the adjustment, to a certain extent, of the chemical composition of the glass precursor; and (3) it permits recovering marketable materials at different stages of the process.

  3. Preparation and characterization of VB metal group glass for optical fiber communication devices

    Aranha, N.; Barbosa, L.C.; Garrido, F.M.S.; Alves, O.L.

    1990-01-01

    In this work was prepared the glass of composition Nb 2 O 5 (25.04%) - PbO (23.91%) - P 2 O 5 (34.25%) - K 2 O (16.80%) using a RF induction furnace at temperature of 1400 C for two hours under ambient atmosphere. The obtained glass are annealed at 300 C. The samples (powder and thin plates) was characterized by X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), UV-Vis spectroscopy and by determination of the thermal coefficient of expansion (dilatometry). Results shown the formation of a very homogeneous glass with a thermal coefficient of expansion (α) of 22.7.10 -6 C -1 . The ir bands suggest the formation of a phosphate glass with a good transmission in the region of 2.0-2.9 microns (5000-3400 cm -1 ). The transmission spectrum shows that the material is transparent in the region of 400-1000 nm with a cut-off at near 350nm. (author) [pt

  4. Characterization of the Italian glasses and their interaction with clay Task 3 Characterization of radioactive waste forms a series of final reports (1985-89) No 23

    Cantale, C.; Castelli, S.; Donato, A.; Traverso, D.M.

    1991-01-01

    The objective of this research work was the selection of a borosilicate glass composition suitable for the solidification of the HLW stream coming from the treatment of all the high-level wastes stored in Italy (MTR, Candu and Elk River) and the characterization of this glass with reference to the geological disposal. This research work was part of an Italian research project named 'Ulisse project', whose goal was the development and the demonstration of an integrated treatment of all the HLW stored in Italy, after their mixing (resulting waste: MCE waste). The main concept is to carry out a pre-treatment of the wastes, in order to concentrate the HLW fraction and to simplify the vitrification process, separating the most part of the inert salts. The research work concerning the separation process and pilot plant demonstration of the pre-treatment process were carried out in the framework of the CEC R and D programme (Contract No Fl1W-0011-lS). The laboratory studies concerning the vitrification of the resulting HLW streams and the vitrification demonstration in the Italian full-scale, inactive IVET plant complete the 'Ulisse project'. Some glass compositions were prepared and preliminarily characterized. The glass named BAZ was finally selected. A complete characterization of this glass was carried out in order to evaluate its mechanical, physical and physico-chemical properties. The chemical durability was evaluated by the MCC-1 static leach test at 90 0 C, using three different leachants and two surface-area to leachant-volume ratios. The same characterization programme was applied to the BAZ glass produced in the IVET plant during the plant vitrification demonstration programme. A comparison between the two glasses and a critical evaluation of their performances with respect to other nuclear waste glasses' durability was performed. 25 refs.; 46 figs.; 20 tabs

  5. Preparation, mechanical, and in vitro properties of glass fiber-reinforced polycarbonate composites for orthodontic application.

    Tanimoto, Yasuhiro; Inami, Toshihiro; Yamaguchi, Masaru; Nishiyama, Norihiro; Kasai, Kazutaka

    2015-05-01

    Generally, orthodontic treatment uses metallic wires made from stainless steel, cobalt-chromium-nickel alloy, β-titanium alloy, and nickel-titanium (Ni-Ti) alloy. However, these wires are not esthetically pleasing and may induce allergic or toxic reactions. To correct these issues, in the present study we developed glass-fiber-reinforced plastic (GFRP) orthodontic wires made from polycarbonate and E-glass fiber by using pultrusion. After fabricating these GFRP round wires with a diameter of 0.45 mm (0.018 inch), we examined their mechanical and in vitro properties. To investigate how the glass-fiber diameter affected their physical properties, we prepared GFRP wires of varying diameters (7 and 13 µm). Both the GFRP with 13-µm fibers (GFRP-13) and GFRP with 7 µm fibers (GFRP-7) were more transparent than the metallic orthodontic wires. Flexural strengths of GFRP-13 and GFRP-7 were 690.3 ± 99.2 and 938.1 ± 95.0 MPa, respectively; flexural moduli of GFRP-13 and GFRP-7 were 25.4 ± 4.9 and 34.7 ± 7.7 GPa, respectively. These flexural properties of the GFRP wires were nearly equivalent to those of available Ni-Ti wires. GFRP-7 had better flexural properties than GFRP-13, indicating that the flexural properties of GFRP increase with decreasing fiber diameter. Using thermocycling, we found no significant change in the flexural properties of the GFRPs after 600 or 1,200 cycles. Using a cytotoxicity detection kit, we found that the glass fiber and polycarbonate components comprising the GFRP were not cytotoxic within the limitations of this study. We expect this metal-free GFRP wire composed of polycarbonate and glass fiber to be useful as an esthetically pleasing alternative to current metallic orthodontic wire. © 2014 Wiley Periodicals, Inc.

  6. Characterization of the calcium-fluoroaluminosilicate glass prepared by a non-hydrolytic sol-gel route for future dental application as glass ionomer cement

    Alexandre Cestari

    2009-06-01

    Full Text Available Glass ionomer cements are widely employed in dentistry due to their physical, biological and mainly anti-caries properties. Glass ionomers consist of an aluminosilicate glass matrix modified with other elements, and they contain large quantities of fluorine. In this study, we report on the preparation of calcium-fluoroaluminosilicate glasses by a nonhydrolytic sol-gel route as an alternative approach to obtaining alumina-silica matrices. The glass powders were prepared via the non-hydrolytic sol-gel method, by mixing AlCl3, SiCl4, CaF2, AlF3, NaF, and AlPO4. The powders were studied by thermal analysis (TG/DTA/DSC, photoluminescence (PL, nuclear magnetic resonance (NMR27Al-29Si, and X ray diffraction (XRD. TG/DTA/DSC analyses revealed a constant mass loss due to structural changes during the heating process, which was confirmed by NMR and PL. A stable aluminosilicate matrix with potential future application as a glass ionomer base was obtained.

  7. Preparation and spectral analysis of a new Tb3+-doped CaO-MgO-SiO2 glass ceramics

    Cheng Jinshu; Tian Peijing; Zheng Weihong; Xie Jun; Chen Zhenxia

    2009-01-01

    Tb 3+ -doped CaO-MgO-SiO 2 glass ceramics have been prepared and characterized. The structure and optical properties of the glass ceramics were studied by XRD, SEM, Raman, and fluorescence spectra. The precipitated crystalline phase in the glass ceramics was columnar CaMgSi 2 O 6 . Raman spectra showed the introduction of rare earth nearly had no influence on the sample structure. Fluorescence measurements showed that Tb 3+ ions entered into the diopside crystalline phase and induced a much stronger emission in the glass ceramics than that in the corresponding glass. With increase of Tb 3+ content and the introduction of Gd 3+ , the fluorescence intensity of the luminescent glass ceramic increased

  8. Preparation of tubular urease immobilized on the inner wall of glass tube by radiation-polymerization

    Tanaka, Y; Hayashi, T; Kawashima, K [National Food Research Inst., Yatabe, Ibaraki (Japan); Oka, O

    1981-03-01

    A method to prepare immobilized urease on the inner wall of a glass tube by radiation-polymerization under frozen state was investigated. As a part of a continuous flow analyzer, i.w.. Technicon Auto Analyzer II, the immobilized urease tube of 1 cm length was set and used for the routine determination of urea. This flow-through system could measure urea concentration of up to 30 mM at rate of 30 samples per hour. The system were possible to assay 2000 to 3000 samples, continuously in practice. The activity of the urease tube stored in a refrigerator maintained 94% of the initial activity after 115 days.

  9. Preparation of tubular urease immobilized on the inner wall of glass tube by radiation-polymerization

    Tanaka, Yoshikazu; Hayashi, Toru; Kawashima, Koji; Oka, Osamu.

    1981-01-01

    A method to prepare immobilized urease on the inner wall of a glass tube by radiation-polymerization under frozen state was investigated. As a part of a continuous flow analyzer, i.w.. Technicon Auto Analyzer II, the immobilized urease tube of 1 cm length was set and used for the routine determination of urea. This flow-through system could measure urea concentration of up to 30 mM at rate of 30 samples per hour. The system were possible to assay 2000 to 3000 samples, continuously in practice. The activity of the urease tube stored in a refrigirator maintained 94% of the initial activity after 115 days. (author)

  10. Final Report - Testing of Optimized Bubbler Configuration for HLW Melter VSL-13R2950-1, Rev. 0, dated 6/12/2013

    Kruger, Albert A.; Pegg, I. L.; Callow, R. A.; Joseph, I.; Matlack, K. S.; Kot, W. K.

    2013-11-13

    The principal objective of this work was to determine the glass production rate increase and ancillary effects of adding more bubbler outlets to the current WTP HLW melter baseline. This was accomplished through testing on the HLW Pilot Melter (DM1200) at VSL. The DM1200 unit was selected for these tests since it was used previously with several HLW waste streams including the four tank wastes proposed for initial processing at Hanford. This melter system was also used for the development and optimization of the present baseline WTP HLW bubbler configuration for the WTP HLW melter, as well as for MACT testing for both HLW and LAW. Specific objectives of these tests were to: Conduct DM1200 melter testing with the baseline WTP bubbling configuration and as augmented with additional bubblers. Conduct DM1200 melter testing to differentiate the effects of total bubbler air flow and bubbler distribution on glass production rate and cold cap formation. Collect melter operating data including processing rate, temperatures at a variety of locations within the melter plenum space, melt pool temperature, glass melt density, and melter pressure with the baseline WTP bubbling configuration and as augmented with additional bubblers. Collect melter exhaust samples to compare particulate carryover for different bubbler configurations. Analyze all collected data to determine the effects of adding more bubblers to the WTP HLW melter to inform decisions regarding future lid re-designs. The work used a high aluminum HLW stream composition defined by ORP, for which an appropriate simulant and high waste loading glass formulation were developed and have been previously processed on the DM1200.

  11. Preparation and Elastic Moduli of Germanate Glass Containing Lead and Bismuth

    Wan M. M. Yunus

    2012-04-01

    Full Text Available This paper reports the rapid melt quenching technique preparation for the new family of bismuth-lead germanate glass (BPG systems in the form of (GeO260–(PbO40−x–(½Bi2O3x where x = 0 to 40 mol%. Their densities with respect of Bi2O3 concentration were determined using Archimedes’ method with acetone as a floatation medium. The current experimental data are compared with those of bismuth lead borate (B2O320–(PbO80−x–(Bi2O3x. The elastic properties of BPG were studied using the ultrasonic pulse-echo technique where both longitudinal and transverse sound wave velocities have been measured in each glass samples at a frequency of 15 MHz and at room temperature. Experimental data shows that all the physical parameters of BPG including density and molar volume, both longitudinal and transverse velocities increase linearly with increasing of Bi2O3 content in the germanate glass network. Their elastic moduli such as longitudinal, shear and Young’s also increase linearly with addition of Bi2O3 but the bulk modulus did not. The Poisson’s ratio and fractal dimensionality are also found to vary linearly with the Bi2O3 concentration.

  12. Preparation and elastic moduli of germanate glass containing lead and bismuth.

    Sidek, Hj A A; Bahari, Hamid R; Halimah, Mohamed K; Yunus, Wan M M

    2012-01-01

    This paper reports the rapid melt quenching technique preparation for the new family of bismuth-lead germanate glass (BPG) systems in the form of (GeO(2))(60)-(PbO)(40-) (x)-(½Bi(2)O(3))(x) where x = 0 to 40 mol%. Their densities with respect of Bi(2)O(3) concentration were determined using Archimedes' method with acetone as a floatation medium. The current experimental data are compared with those of bismuth lead borate (B(2)O(3))(20)-(PbO)(80-) (x)-(Bi(2)O(3))(x). The elastic properties of BPG were studied using the ultrasonic pulse-echo technique where both longitudinal and transverse sound wave velocities have been measured in each glass samples at a frequency of 15 MHz and at room temperature. Experimental data shows that all the physical parameters of BPG including density and molar volume, both longitudinal and transverse velocities increase linearly with increasing of Bi(2)O(3) content in the germanate glass network. Their elastic moduli such as longitudinal, shear and Young's also increase linearly with addition of Bi(2)O(3) but the bulk modulus did not. The Poisson's ratio and fractal dimensionality are also found to vary linearly with the Bi(2)O(3) concentration.

  13. Preparation and nonlinear optical properties of indium nanocrystals in sodium borosilicate glass by the sol–gel route

    Zhong, Jiasong; Xiang, Weidong; Zhao, Haijun; Chen, Zhaoping; Liang, Xiaojuan; Zhao, Wenguang; Chen, Guoxin

    2012-01-01

    Graphical abstract: The sodium borosilicate glass doped with indium nanocrystals have been successfully prepared by sol–gel methods. And the indium nanocrystals in tetragonal crystal system have formed uniformly in the glass, and the average diameter of indium nanocrystals is about 30 nm. The third-order optical nonlinear refractive index γ, absorption coefficient β, and susceptibility χ (3) of the glass are determined to be −4.77 × 10 −16 m 2 /W, 2.67 × 10 −9 m/W, and 2.81 × 10 −10 esu, respectively. Highlights: ► Indium nanocrystals embedded in glass matrix have been prepared by sol–gel route. ► The crystal structure and composition are investigated by XRD and XPS. ► Size and distribution of indium nanocrystals is determined by TEM. ► The third-order optical nonlinearity is investigated by using Z-scan technique. -- Abstract: The sodium borosilicate glass doped with indium nanocrystals have been successfully prepared by sol–gel route. The thermal stability behavior of the stiff gel is investigated by thermogravimetric (TG) and differential thermal (DTA) analysis. The crystal structure of the glass is characterized by X-ray powder diffraction (XRD). Particle composition is determined by X-ray photoelectron spectroscopy (XPS). Size and distribution of the nanocrystals are characterized by transmission electron microscopy (TEM) as well as high-resolution transmission electron microscopy (HRTEM). Results show that the indium nanocrystals in tetragonal crystal structure have formed in glass, and the average diameter is about 30 nm. Further, the glass is measured by Z-scan technique to investigate the nonlinear optical (NLO) properties. The third-order NLO coefficient χ (3) of the glass is determined to be 2.81 × 10 −10 esu. The glass with large third-order NLO coefficient is promising materials for applications in optical devices.

  14. Preliminary formulation studies for a ''hydroceramic'' alternative waste form for INEEL HLW

    Siemer, D.D.; Gougar, M.L.D.; Grutzeck, M.W.; Scheetz, B.E.

    1999-01-01

    Herein the authors discuss scoping studies performed to develop an efficient way to prepare the Idaho National Engineering and Environmental Laboratory (INEEL) nominally high-level (∼40 W/m 3 ) calcined radioactive waste (HLW) and liquid metal (sodium) reactor coolants for disposal. The investigated approach implements the chemistry of Hanford's cancrinite-making clay reaction process via Oak Ridge National Laboratory's (ORNL's) formed-under-elevated-temperatures-and-pressures concrete monolith-making technology to make hydroceramics (HCs). The HCs differ from conventional Portland cement/blast furnace slag (PC/BFS) grouts in that the binder minerals formed during the curing process are hydrated alkali-aluminosilicates (feldspathoids-sodalites, cancrinites, and zeolites) rather than hydrated calcium silicates (CSH). This is desirable because (a) US defense-type radioactive wastes generally contain much more sodium and aluminum than calcium; (b) sodalites/cancrinites do a much better job of retaining the anionic components of real radioactive waste (e.g., nitrate) than do calcium silicates; (c) natural feldspathoids form from glasses (and therefore are more stable) in that region of the United States where a repository for this sort of waste could be sited; and (d) if eventually deemed necessary, feldspathoid-type concrete wasteforms could be hot-isostatically-pressed into even more durable materials without removing them from their original canisters

  15. Crystallization in high-level waste glass: A review of glass theory and noteworthy literature

    Christian, J. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-08-18

    There is a fundamental need to continue research aimed at understanding nepheline and spinel crystal formation in high-level waste (HLW) glass. Specifically, the formation of nepheline solids (K/NaAlSiO4) during slow cooling of HLW glass can reduce the chemical durability of the glass, which can cause a decrease in the overall durability of the glass waste form. The accumulation of spinel solids ((Fe, Ni, Mn, Zn)(Fe, Cr)2O4), while not detrimental to glass durability, can cause an array of processing problems inside HLW glass melters. In this review, the fundamental differences between glass and solid-crystals are explained using kinetic, thermodynamic, and viscosity arguments, and several highlights of glass-crystallization research, as it pertains to high-level waste vitrification, are described. In terms of mitigating spinel in the melter and both spinel and nepheline formation in the canister, the complexity of HLW glass and the intricate interplay between thermal, chemical, and kinetic factors further complicates this understanding. However, new experiments seeking to elucidate the contributing factors of crystal nucleation and growth in waste glass, and the compilation of data from older experiments, may go a long way towards helping to achieve higher waste loadings while developing more efficient processing strategies. Higher waste loadings and more efficient processing strategies will reduce the overall HLW Hanford Tank Waste Treatment and Immobilization Plant (WTP) vitrification facilities mission life.

  16. Integrated HLW Conceptual Process Flowsheet(s) for the Crystalline Silicotitanate Process SRDF-98-04

    Jacobs, R.A.

    1998-01-01

    The Strategic Research and Development Fund (SRDF) provided funds to develop integrated conceptual flowsheets and material balances for a CST process as a potential replacement for, or second generation to, the ITP process. This task directly supports another SRDF task: Glass Form for HLW Sludge with CST, SRDF-98-01, by M. K. Andrews which seeks to further develop sludge/CST glasses that could be used if the ITP process were replaced by CST ion exchange. The objective of the proposal was to provide flowsheet support for development and evaluation of a High Level Waste Division process to replace ITP. The flowsheets would provide a conceptual integrated material balance showing the impact on the HLW division. The evaluation would incorporate information to be developed by Andrews and Harbour on CST/DWPF glass formulations and provide the bases for evaluating the economic impact of the proposed replacement process. Coincident with this study, the Salt Disposition Team began its evaluation of alternatives for disposition of the HLW salts in the SRS waste tanks. During that time, the CST IX process was selected as one of four alternatives (of eighteen Phase II alternatives) for further evaluation during Phase III

  17. [Depyrogenation test regarding inox and glass containers in the preparation of parenteral nutrition mixtures].

    Lajoinie, A; Vasselon, P; Tall, M-L; Salmon, D; Bréant, V; Diouf, E; Pivot, C; Pirot, F

    2012-09-01

    The preparation of parenteral nutrition mixture (PNM) in an open chamber requires the use of intermediate containers sterile and non-pyrogenic. A sterilization of containers by moist heat in large autoclaves is the suitable method. However, sterilization by moist heat is not a depyrogenation method. In our study, we report the validation of a sterilization and depyrogenation method for containers by dry heat using a convection oven. Sterilization and depyrogenation of material by dry heat have been audited by the reduction of at least three logarithms of original endotoxin rate. The containers were initially artificially contaminated with a suspension of endotoxin for 16 hours. Contaminated containers were placed in an oven with revolving heat at 250 °C for 1 hour. After treatment with dry heat, the residual endotoxin levels in the containers were determined by a kinetic chromogenic method. After treatment with dry heat, the average log reductions of endotoxin levels were respectively, for glass and steel containers, 4.78 ± 0.07 and 4.87 ± 0.03. The present validation study confirms the effectiveness of treatment with dry heat for sterilization and depyrogenation of glass and steel containers. This method of sterilization and depyrogenation meets the microbiological quality requirements for the preparation of MNP. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  18. Magnetic properties of magnetic glass-like carbon prepared from furan resin alloyed with magnetic fluid

    Nakamura, Kazumasa, E-mail: naka@sss.fukushima-u.ac.jp [Materials Science Area, Graduate School of Symbiotic Systems Science and Technology, Fukushima University, 1 Kanayagawa, Fukushima 960-1296 (Japan); Okuyama, Kyoko [Materials Science Area, Graduate School of Symbiotic Systems Science and Technology, Fukushima University, 1 Kanayagawa, Fukushima 960-1296 (Japan); Takase, Tsugiko [Institute of Environmental Radioactivity (IER), Fukushima University, 1 Kanayagawa, Fukushima 960-1296 (Japan)

    2017-03-01

    Magnetic glass-like carbons that were heat-treated at different temperatures or were filled with different magnetic nanoparticle contents were prepared from furan resin alloyed with magnetic fluid (MF) or Fe{sub 3}O{sub 4} powder in their liquid-phase states during mixing. Compared to the Fe{sub 3}O{sub 4} powder-alloyed carbon, the MF-alloyed carbon has highly dispersed the nanoparticles, and has the excellent saturation magnetization and coercivity. It is implied that saturation magnetizations are related to changes in the types of phases for the nanoparticles and the relative intensities of X-ray diffraction peaks for iron and iron-containing compounds in the carbons. Additionally, the coercivities are possibly affected by the size and crystallinity of the nanoparticles, the relative amounts of iron, and the existence of amorphous compounds on the carbon surfaces. - Highlights: • Magnetic glass-like carbons were prepared from furan resin alloyed with magnetic fluid. • The nanoparticles of MF-alloyed GLCs were highly dispersed. • MF-alloyed GLCs had excellent magnetic properties compared to powder-alloyed ones. • The magnetic properties changed with treatment temperature and nanoparticle content. • The changes in magnetic properties were investigated with XRD and FE-SEM.

  19. Preparation of SnO_2-Glass Composite Containing Cu Particles Reduced from Copper Ions in Glass Matrix : Effect of Glass Particle Size on Microstructure and Electrical Property

    Haruhisa, SHIOMI; Kaori, UMEHARA; Faculty of Engineering and Design, Kyoto Institute of Technology; Faculty of Engineering and Design, Kyoto Institute of Technology

    2000-01-01

    An attempt was made to improve the electrical properties of SnO_2-glass composites by dispersing Cu particles with low resistivity and positive temperature coefficient of resistance(TCR)in the glass matrix. Cu metal particles were precipitated by reducing Cu_2O previously dissolved into the matrix glass by adding LaB_6 as a reducing agent. The effect of the glass particle size, which influences the homogeneity of LaB_6 dispersion in the powder mixture before firing, on the Cu precipitation in...

  20. Novel dielectric properties of glasses prepared by quenching melts of Bi-Ca-Sr-Cu-O cuprates

    Varma, K.B.R.; Subbanna, G.N.; Ramakrishnan, T.V. (Materials Research Centre, Indian Inst. of Science, Bangalore (India) Dept. of Physics, Indian Inst. of Science, Bangalore (India)); Rao, C.N.R. (Solid State and Structural Chemistry Unit, Indian Inst. of Science, Bangalore (India))

    1989-12-01

    Glasses, prepared from the melts of Bi{sub 2}(Ca,Sr){sub n+1}Cu{sub n}O{sub 2n+4} (n=1, 2 and 3) have been characterized by various techniques. These glasses exhibit relatively high dielectric constants, high electrical conductivity, a ferroelectric-like dielectric hysteresis loop and pyroelectric effect at 300K. They also show weak microwave absorption at 77K. (orig.).

  1. Synthesis and structure of Na-Li-Si-Al-P-O-N glasses prepared by melt nitridation using NH3

    Kidar, A.; Pomeroy, M.J.; Hampshire, S.; Mercier, C.; Leriche, A.; Revel, B.

    2012-01-01

    Na-Li-Si-Al-P-O-N glasses have been prepared by nitridation of a pre-synthesized Na 2 O-Li 2 O-SiO 2 -P 2 O 5 -Al 2 O 3 glass under anhydrous ammonia. Nitrogen for oxygen substitution increases the network connectivity leading to increases in microhardness and glass transition temperature. Raman and 31 P MAS-NMR spectroscopy indicate sequential nitridation reactions forming PO 3 N and PO 2 N 2 species. The data collected so far show no evidence of N/O substitutions in the silicate sub-network. (authors)

  2. Final Report Tests On The Duramelter 1200 HLW Pilot Melter System Using AZ-101 HLW Simulants VSL-02R0100-2, Rev. 1, 2/17/03

    Kruger, A.A.; Matlack, K.S.; Kot, W.K.; Bardakci, T.; Gong, W.; D'Angelo, N.A.; Schatz, T.R.; Pegg, I.L.

    2011-01-01

    This document provides the final report on data and results obtained from a series of nine tests performed on the one-third scale DuraMelter(trademark) 1200 (DM1200) HLW Pilot Melter system that has been installed at VSL with an integrated prototypical off-gas treatment system. That system has replaced the DM1000 system that was used for HLW throughput testing during Part B1 (1). Both melters have similar melt surface areas (1.2 m 2 ) but the DM1200 is prototypical of the present RPP-WTP HLW melter design whereas the DM1000 was not. These tests were performed under a corresponding RPP-WTP Test Specification and associated Test Plans. The nine tests reported here were preceded by an initial series of short-duration tests conducted to support the start-up and commissioning of this system. This report is a followup to the previously issued Preliminary Data Summary Reports. The DM1200 system was deployed for testing and confirmation of basic design, operability, flow sheet, and process control assumptions as well as for support of waste form qualification and permitting. These tests include data on processing rates, off-gas treatment system performance, recycle stream compositions, as well as process operability and reliability. Consequently, this system is a key component of the overall HLW vitrification development strategy. The primary objective of the present series of tests was to determine the effects of a variety of parameters on the glass production rate in comparison to the RPP-WTP HL W design basis of 400 kg/m 2 /d. Previous testing on the DMIOOO system (1) concluded that achievement of that rate with simulants of projected WTP melter feeds (AZ-101 and C-106/AY-102) was unlikely without the use of bubblers. As part of those tests, the same feed that was used during the cold-commissioning of the West Valley Demonstration Project (WVDP) HLW vitrification system was run on the DM1000 system. The DM1000 tests reproduced the rates that were obtained at the larger

  3. FINAL REPORT TESTS ON THE DURAMELTER 1200 HLW PILOT MELTER SYSTEM USING AZ-101 HLW SIMULANTS VSL-02R0100-2 REV 1 2/17/03

    KRUGER AA; MATLACK KS; KOT WK; BARDAKCI T; GONG W; D' ANGELO NA; SCHATZ TR; PEGG IL

    2011-12-29

    This document provides the final report on data and results obtained from a series of nine tests performed on the one-third scale DuraMelter{trademark} 1200 (DM1200) HLW Pilot Melter system that has been installed at VSL with an integrated prototypical off-gas treatment system. That system has replaced the DM1000 system that was used for HLW throughput testing during Part B1 [1]. Both melters have similar melt surface areas (1.2 m{sup 2}) but the DM1200 is prototypical of the present RPP-WTP HLW melter design whereas the DM1000 was not. These tests were performed under a corresponding RPP-WTP Test Specification and associated Test Plans. The nine tests reported here were preceded by an initial series of short-duration tests conducted to support the start-up and commissioning of this system. This report is a followup to the previously issued Preliminary Data Summary Reports. The DM1200 system was deployed for testing and confirmation of basic design, operability, flow sheet, and process control assumptions as well as for support of waste form qualification and permitting. These tests include data on processing rates, off-gas treatment system performance, recycle stream compositions, as well as process operability and reliability. Consequently, this system is a key component of the overall HLW vitrification development strategy. The primary objective of the present series of tests was to determine the effects of a variety of parameters on the glass production rate in comparison to the RPP-WTP HL W design basis of 400 kg/m{sup 2}/d. Previous testing on the DMIOOO system [1] concluded that achievement of that rate with simulants of projected WTP melter feeds (AZ-101 and C-106/AY-102) was unlikely without the use of bubblers. As part of those tests, the same feed that was used during the cold-commissioning of the West Valley Demonstration Project (WVDP) HLW vitrification system was run on the DM1000 system. The DM1000 tests reproduced the rates that were obtained at the

  4. Preparation and characterization of Fe-based bulk metallic glasses in plate form

    Lavorato, G.C.; Fiore, G.; Castellero, A.; Baricco, M.; Moya, J.A.

    2012-01-01

    Amorphous alloys with composition (at%) Fe 48 Cr 15 Mo 14 C 15 B 6 Gd 2 (alloy A) and Fe 48 Cr 15 Mo 14 C 15 B 6 Y 2 (alloy B) were prepared either using pure elements (A and B1) and a commercial AISI430 steel as a base material (B2). When prepared from pure elements both alloys (A and B1) could be cast in plate form with a fixed thickness of 2 mm and variable lengths between 10 and 20 mm by means of copper-mold injection in air atmosphere. In the case of alloy B2, prepared using commercial grade raw materials, rods of 2 mm diameter were obtained. X-ray diffraction and scanning electron microscopy observations confirmed that an amorphous structure was obtained in all the as-cast samples. A minor fraction of crystalline phases (oxides and carbides) was detected on the as-cast surface. Differential scanning calorimetry measurements showed a glass transition temperature at 856 K for alloy A and 841 K for alloy B1, and an onset crystallization temperature of 887 K for alloy A and 885 K for alloy B1. In the case of alloy B2 a slightly different crystallization sequence was observed. Values of hardness (∼13 GPa) and the Young modulus (∼180 GPa) were measured by nanoindentation for both the alloys. The effects of adverse casting conditions (such as air atmosphere, non-conventional injection copper mold casting and partial replacement of pure elements with commercial grade raw materials) on the glass formation and properties of the alloy are discussed.

  5. Preparation and characterization of Fe-based bulk metallic glasses in plate form

    Lavorato, G.C. [INTECIN (FIUBA-CONICET), Paseo Colon 850, Capital Federal (Argentina); Dipartimento di Chimica IFM and NIS, Universita di Torino, Torino (Italy); Fiore, G.; Castellero, A.; Baricco, M. [Dipartimento di Chimica IFM and NIS, Universita di Torino, Torino (Italy); Moya, J.A., E-mail: jmoya.fi.uba@gmail.com [IESIING, Facultad de Ingenieria e Informatica, UCASAL, Salta (Argentina); CONICET (Argentina)

    2012-08-15

    Amorphous alloys with composition (at%) Fe{sub 48}Cr{sub 15}Mo{sub 14}C{sub 15}B{sub 6}Gd{sub 2} (alloy A) and Fe{sub 48}Cr{sub 15}Mo{sub 14}C{sub 15}B{sub 6}Y{sub 2} (alloy B) were prepared either using pure elements (A and B1) and a commercial AISI430 steel as a base material (B2). When prepared from pure elements both alloys (A and B1) could be cast in plate form with a fixed thickness of 2 mm and variable lengths between 10 and 20 mm by means of copper-mold injection in air atmosphere. In the case of alloy B2, prepared using commercial grade raw materials, rods of 2 mm diameter were obtained. X-ray diffraction and scanning electron microscopy observations confirmed that an amorphous structure was obtained in all the as-cast samples. A minor fraction of crystalline phases (oxides and carbides) was detected on the as-cast surface. Differential scanning calorimetry measurements showed a glass transition temperature at 856 K for alloy A and 841 K for alloy B1, and an onset crystallization temperature of 887 K for alloy A and 885 K for alloy B1. In the case of alloy B2 a slightly different crystallization sequence was observed. Values of hardness ({approx}13 GPa) and the Young modulus ({approx}180 GPa) were measured by nanoindentation for both the alloys. The effects of adverse casting conditions (such as air atmosphere, non-conventional injection copper mold casting and partial replacement of pure elements with commercial grade raw materials) on the glass formation and properties of the alloy are discussed.

  6. The dosimetric properties of phosphate glass systems prepared by different chemical nanomaterials.

    Abdelhalim, Mohamed Anwar K; Al-Shamrani, Bandar Mora

    2016-12-01

    The synthesis and characterization of glass systems were carried out using prepared nanocrystals injected into a glass matrix as a thermoluminescence (TL) activator using the melt-quenching method. Sample 1 was prepared as [40P 2 O 5 50BaO:2.5MgO, 2.5Na 2 O, 5TiO 2 ], sample 2 as [37.5P 2 O 5 37.5CaO:25TiO 2 ] and sample 3 as [50P 2 O 5 -50Li 2 O]. Formation of the synthesized compound was confirmed by studying the X-ray diffraction (XRD) patterns and scanning electron microscopy (SEM) images. An annealing procedure was carried out for 1 h at 400 °C. The glow curve position and shape shifted dramatically and linearly to the higher temperature values on increasing the heating rate. A heating rate of 30 °C/s was the most suitable for obtaining a high TL response. Samples 2 and 3 have the highest TL response, which approached the effective atomic number (Z eff ) of natural bone. The observed TL sensitivity of the prepared samples 2 and 3 is less than that of commercially available 'TLD-200 chips' and LiF:Mg,Ti (TLD-100) phosphor. Sample [37.5P 2 O 5 37.5CaO:25TiO 2 ] would be useful in personal and environmental dosimetry for measuring high doses of gamma radiation. Sample [50P 2 O 5 -50Li 2 O] is a good dosimeter, although it requires the addition of an appropriate transitional metal (activator) to overcome the problem of high fading. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  7. Preparation and studies on surface modifications of calcium-silico-phosphate ferrimagnetic glass-ceramics in simulated body fluid

    Sharma, K.; Dixit, A.; Singh, Sher; Jagannath,; Bhattacharya, S.; Prajapat, C.L.; Sharma, P.K.; Yusuf, S.M.; Tyagi, A.K.; Kothiyal, G.P.

    2009-01-01

    The structure and magnetic behaviour of 34SiO 2 -(45 - x) CaO-16P 2 O 5 -4.5 MgO-0.5 CaF 2 - x Fe 2 O 3 (where x = 5, 10, 15, 20 wt.%) glasses have been investigated. Ferrimagnetic glass-ceramics are prepared by melt quench followed by controlled crystallization. The surface modification and dissolution behaviour of these glass-ceramics in simulated body fluid (SBF) have also been studied. Phase formation and magnetic behaviour have been studied using XRD and SQUID magnetometer. The room temperature Moessbauer study has been done to monitor the local environment around Fe cations and valence state of Fe ions. X-ray photoelectron spectroscopy (XPS) was used to study the surface modification in glass-ceramics when immersed in simulated body fluid. Formation of bioactive layer in SBF has been ascertained using X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The SBF solutions were analyzed using an absorption spectrophotometer. The magnetic measurements indicated that all these glasses possess paramagnetic character and the [Fe 2+ /Fe 3+ ] ions ratio depends on the composition of glass and varied with Fe 2 O 3 concentration in glass matrix. In glass-ceramics saturation magnetization increases with increase in amount of Fe 2 O 3 . The nanostructure of hematite and magnetite is formed in the glass-ceramics with 15 and 20 wt.% Fe 2 O 3 , which is responsible for the magnetic property of these glass-ceramics. Introduction of Fe 2 O 3 induces several modifications at the glass-ceramics surface when immersed in SBF solution and thereby affecting the surface dissolution and the formation of the bioactive layer.

  8. Isothermal crystallization kinetics in simulated high-level nuclear waste glass

    Vienna, J.D.; Hrma, P.; Smith, D.E.

    1997-01-01

    Crystallization kinetics of a simulated high-level waste (HLW) glass were measured and modelled. Kinetics of acmite growth in the standard HW39-4 glass were measured using the isothermal method. A time-temperature-transformation (TTT) diagram was generated from these data. Classical glass-crystal transformation kinetic models were empirically applied to the crystallization data. These models adequately describe the kinetics of crystallization in complex HLW glasses (i.e., RSquared = 0.908). An approach to measurement, fitting, and use of TTT diagrams for prediction of crystallinity in a HLW glass canister is proposed

  9. Fabrication and characterization of MCC approved testing material - ATM-8 glass

    Wald, J.W.

    1985-10-01

    The Materials Characterization Center (MCC) Approved Testing Material ATM-8 is a borosilicate glass that incorporates elements typical of high-level waste (HLW) resulting from the reprocessing of commercial nuclear reactor fuel. Its composition is based upon the simulated HLW glass type 76-68 (Mendel, J.E. et al., 1977, Annual Report of the Characteristics of High-Level Waste Glasses, BNWL-2252, Pacific Northwest Laboratory, Richland, Washington), to which depleted uranium, technetium-99, neptunium-237 and plutonium-239 have been added at moderate to low levels. The glass was requested by the Nevada Nuclear Waste Storage Investigations (NNWSI) Project. It was produced by the MCC at the Pacific Northwest Laboratory (PNL) operated for the Department of Energy (DOE) by Battelle Memorial Institute. ATM-8 glass was produced in April of 1984, and is the second in a series of testing materials for NNWSI. This report discusses its fabrication (starting materials, batch and glass preparation, measurement and testing equipment, other equipment, procedures, identification system and materials availability and storage, and characterization (bulk density) measurements, chemical analysis, microscopic examination, and x-ray diffraction analysis. 4 refs., 2 figs., 10 tabs

  10. Alkaline resistant phosphate glasses and method of preparation and use thereof

    Brow, Richard K.; Reis, Signo T.; Velez, Mariano; Day, Delbert E.

    2010-01-26

    A substantially alkaline resistant calcium-iron-phosphate (CFP) glass and methods of making and using thereof. In one application, the CFP glass is drawn into a fiber and dispersed in cement to produce glass fiber reinforced concrete (GFRC) articles having the high compressive strength of concrete with the high impact, flexural and tensile strength associated with glass fibers.

  11. Effect of sintering temperature on the microstructure and properties of foamed glass-ceramics prepared from high-titanium blast furnace slag and waste glass

    Chen, Chang-hong; Feng, Ke-qin; Zhou, Yu; Zhou, Hong-ling

    2017-08-01

    Foamed glass-ceramics were prepared via a single-step sintering method using high-titanium blast furnace slag and waste glass as the main raw materials The influence of sintering temperature (900-1060°C) on the microstructure and properties of foamed glass-ceramics was studied. The results show that the crystal shape changed from grainy to rod-shaped and finally turned to multiple shapes as the sintering temperature was increased from 900 to 1060°C. With increasing sintering temperature, the average pore size of the foamed glass-ceramics increased and subsequently decreased. By contrast, the compressive strength and the bulk density decreased and subsequently increased. An excessively high temperature, however, induced the coalescence of pores and decreased the compressive strength. The optimal properties, including the highest compressive strength (16.64 MPa) among the investigated samples and a relatively low bulk density (0.83 g/cm3), were attained in the case of the foamed glass-ceramics sintered at 1000°C.

  12. Glass sample preparation and performance investigations. [solar x-ray imager

    Johnson, R. Barry

    1992-01-01

    This final report details the work performed under this delivery order from April 1991 through April 1992. The currently available capabilities for integrated optical performance modeling at MSFC for large and complex systems such as AXAF were investigated. The Integrated Structural Modeling (ISM) program developed by Boeing for the U.S. Air Force was obtained and installed on two DECstations 5000 at MSFC. The structural, thermal and optical analysis programs available in ISM were evaluated. As part of the optomechanical engineering activities, technical support was provided in the design of support structure, mirror assembly, filter wheel assembly and material selection for the Solar X-ray Imager (SXI) program. As part of the fabrication activities, a large number of zerodur glass samples were prepared in different sizes and shapes for acid etching, coating and polishing experiments to characterize the subsurface damage and stresses produced by the grinding and polishing operations. Various optical components for AXAF video microscope and the x-ray test facility were also fabricated. A number of glass fabrication and test instruments such as a scatter plate interferometer, a gravity feed saw and some phenolic cutting blades were fabricated, integrated and tested.

  13. Final Report - Effects of High Spinel and Chromium Oxide Crystal Contents on Simulated HLW Vitrification in DM100 Melter Tests, VSL-09R1520-1, Rev. 0, dated 6/22/09

    Kruger, Albert A.; Matlack, K. S.; Kot, W.; Pegg, I. L.; Chaudhuri, M.; Lutze, W.

    2013-11-13

    The principal objective of the work was to evaluate the effects of spinel and chromium oxide particles on WTP HLW melter operations and potential impacts on melter life. This was accomplished through a combination of crucible-scale tests, settling and rheological tests, and tests on the DM100 melter system. Crucible testing was designed to develop and identify HLW glass compositions with high waste loadings that exhibit formation of crystalline spinel and/or chromium oxide phases up to relatively high crystal contents (i.e., > 1 vol%). Characterization of crystal settling and the effects on melt rheology was performed on the HLW glass formulations. Appropriate candidate HLW glass formulations were selected, based on characterization results, to support subsequent melter tests. In the present work, crucible melts were formulated that exhibit up to about 4.4 vol% crystallization.

  14. Preparation of orthophosphate glasses in the MgO-CaO-SiO2-Nb2O5-P2O5 system.

    Lee, Sungho; Ueda, Kyosuke; Narushima, Takayuki; Nakano, Takayoshi; Kasuga, Toshihiro

    2017-01-01

    Niobia/magnesia-containing orthophosphate invert glasses were successfully prepared in our earlier work. Orthophosphate groups in the glasses were cross-linked by tetrahedral niobia (NbO4) and magnesia. The aim of this work is to prepare calcium orthophosphate invert glasses containing magnesia and niobia, incorporating silica, and to evaluate their structures and releasing behaviors. The glasses were prepared by melt-quenching, and their structures and ion-releasing behaviors were evaluated. 31P solid-state nuclear magnetic resonance (NMR) and Raman spectroscopies showed the glasses consist of orthophosphate (PO4), orthosilicate (SiO4), and NbO4 tetrahedra. NbO4 and MgO in the glasses act as network formers. By incorporating SiO2 into the glasses, the chemical durability of the glasses was slightly improved. The glasses reheated at 800°C formed the orthophosphate crystalline phases, such as β-Ca3(PO4)2, Mg3(PO4)2 and Mg3Ca3(PO4)4 in the glasses. The chemical durability of the crystallized glasses was slightly improved. Orthosilicate groups and NbO4 in the glasses coordinated with each other to form Si-O-Nb bonds. The chemical durability of the glasses was slightly improved by addition of SiO2, since the field strength of Si is larger than that of Ca or Mg.

  15. Preparation of high-purity Pr(3+) doped Ge–Ga–Sb–Se glasses with intensive middle infrared luminescence

    Karaksina, E.V.; Shiryaev, V.S., E-mail: shiryaev@ihps.nnov.ru; Kotereva, T.V.; Churbanov, M.F.

    2016-02-15

    Glass materials with high emission characteristics and low content of limiting impurities are required for creation of devices for middle infrared (mid-IR) fiber optics. The paper presents the results of preparation of high-purity Pr{sup 3+}-doped Ga{sub x}Ge{sub y}Sb{sub z}Se{sub 1−(x+y+z)} (x=3÷4, y=20÷26, z=5÷11) glasses. The multi-stage technique for synthesis of these glasses is developed. It is based on chemical distillation purification of glass components and the transport reaction for purification of gallium. Transmitting, as well as thermal and luminescent properties of glasses are investigated. The content of limiting impurities of oxygen, carbon and hydrogen in the glass samples was ≤0.2 ppm wt. The 1300–3000 ppm wt Pr{sup 3+}-doped Ga–Ge–Sb–Se bulk glasses exhibit an intensive photoluminescence in the spectral range of 3.5–5.5 μm.

  16. Preparation and investigation of GaxGe25As15Se60-x (x = 1 ÷ 5) glasses

    Shiryaev, V. S.; Karaksina, E. V.; Velmuzhov, A. P.; Sukhanov, M. V.; Kotereva, T. V.; Plekhovich, A. D.; Churbanov, M. F.; Filatov, A. I.

    2017-05-01

    Chalcogenide glasses of GaxGe25As15Se60-x (x = 0; 1; 2; 3; 4; 5) compositions are prepared; their transmission range, optical band gap energy, thermal properties and stability against crystallization are studied. It is shown that these glasses have a high transparency in the mid-IR region (from 0.8 to 15 μm), a high glass transition temperature (≥320 °C) and a low tendency to crystallize. The optical band gap energy of GaxGe25As15Se60-x (x = 0; 1; 2; 3; 4; 5) glasses decreases from 1.68 to 1.43 eV as the gallium content increases and the selenium decreases. Their glass network, according to IR spectroscopy data, consists of Ge(Se1/2)4 tetrahedrons and AsSe3/2 pyramids. The Ga2Ge25As15Se58 and Ga3Ge25As15Se57 glasses have highest stability against crystallization. The content of hydrogen and oxygen impurities in the purest glass samples, fabricated using a combination of chemical distillation purification method and vapor transport reaction technique, does not exceed 0.06 ppm (wt) and 0.5 ppm (wt), respectively.

  17. Final Report - Management of High Sulfur HLW, VSL-13R2920-1, Rev. 0, dated 10/31/2013

    Kruger, Albert A.; Gan, H.; Pegg, I. L.; Feng, Z.; Gan, H; Joseph, I.; Matlack, K. S.

    2013-11-13

    The present report describes results from a series of small-scale crucible tests to determine the extent of corrosion associated with sulfur containing HLW glasses and to develop a glass composition for a sulfur-rich HLW waste stream, which was then subjected to small-scale melter testing to determine the maximum acceptable sulfate loadings. In the present work, a new glass formulation was developed and tested for a projected Hanford HLW composition with sulfate concentrations high enough to limit waste loading. Testing was then performed on the DM10 melter system at successively higher waste loadings to determine the maximum waste loading without the formation of a separate sulfate salt phase. Small scale corrosion testing was also conducted using the glass developed in the present work, the glass developed in the initial phase of this work [26], and a high iron composition, all at maximum sulfur concentrations determined from melter testing, in order to assess the extent of Inconel 690 and MA758 corrosion at elevated sulfate contents.

  18. Studies on the preparation and plasma spherodization of yttrium aluminosilicate glass microspheres for their potential application in liver brachytherapy

    Sreekumar, K. P.; Saxena, S. K.; Kumar, Yogendra; Thiyagarajan, T. K.; Dash, Ashutosh; Ananthapadmanabhan, P. V.; Venkatesh, Meera

    2010-02-01

    Plasma spheroidization exploits the high temperature and high enthalpy available in the thermal plasma jet to melt irregularly shaped powder particles and quench them to get dense spherical particles. Plasma spheroidization is a versatile process and can be applied to metals, ceramics, alloys and composites to obtain fine spherical powders. Radioactive microspheres incorporated with high energetic beta emitting radioisotopes have been reported to be useful in the palliative treatment of liver cancer. These powders are to be prepared in closer range of near spherical morphology in the size range 20-35 microns. Inactive glass samples were prepared by heating the pre-calculated amount of glass forming ingredients in a recrystallized alumina crucible. The glass was formed by keeping the glass forming ingredients at 1700°C for a period of three hours to form a homogeneous melt. After cooling, the glass was recovered from the crucible by crushing and was subsequently powdered mechanically with the help of mortar and pestle. This powder was used as the feed stock for plasma spheroidization using an indigenously developed 40 kW plasma spray system. Experiments were carried out at various operating parameters. The operating parameters were optimised to get spheroidised particles. The powder was sieved to get the required size range before irradiation.

  19. Studies on the preparation and plasma spherodization of yttrium aluminosilicate glass microspheres for their potential application in liver brachytherapy

    Sreekumar, K P; Saxena, S K; Kumar, Yogendra; Thiyagarajan, T K; Dash, Ashutosh; Ananthapadmanabhan, P V; Venkatesh, Meera, E-mail: nair.sreekumar@gmail.co [Laser and Plasma Technology Division, Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Trombay, Mumbai - 400 085 (India)

    2010-02-01

    Plasma spheroidization exploits the high temperature and high enthalpy available in the thermal plasma jet to melt irregularly shaped powder particles and quench them to get dense spherical particles. Plasma spheroidization is a versatile process and can be applied to metals, ceramics, alloys and composites to obtain fine spherical powders. Radioactive microspheres incorporated with high energetic beta emitting radioisotopes have been reported to be useful in the palliative treatment of liver cancer. These powders are to be prepared in closer range of near spherical morphology in the size range 20-35 microns. Inactive glass samples were prepared by heating the pre-calculated amount of glass forming ingredients in a recrystallized alumina crucible. The glass was formed by keeping the glass forming ingredients at 1700{sup 0}C for a period of three hours to form a homogeneous melt. After cooling, the glass was recovered from the crucible by crushing and was subsequently powdered mechanically with the help of mortar and pestle. This powder was used as the feed stock for plasma spheroidization using an indigenously developed 40 kW plasma spray system. Experiments were carried out at various operating parameters. The operating parameters were optimised to get spheroidised particles. The powder was sieved to get the required size range before irradiation.

  20. Studies on the preparation and plasma spherodization of yttrium aluminosilicate glass microspheres for their potential application in liver brachytherapy

    Sreekumar, K P; Saxena, S K; Kumar, Yogendra; Thiyagarajan, T K; Dash, Ashutosh; Ananthapadmanabhan, P V; Venkatesh, Meera

    2010-01-01

    Plasma spheroidization exploits the high temperature and high enthalpy available in the thermal plasma jet to melt irregularly shaped powder particles and quench them to get dense spherical particles. Plasma spheroidization is a versatile process and can be applied to metals, ceramics, alloys and composites to obtain fine spherical powders. Radioactive microspheres incorporated with high energetic beta emitting radioisotopes have been reported to be useful in the palliative treatment of liver cancer. These powders are to be prepared in closer range of near spherical morphology in the size range 20-35 microns. Inactive glass samples were prepared by heating the pre-calculated amount of glass forming ingredients in a recrystallized alumina crucible. The glass was formed by keeping the glass forming ingredients at 1700 0 C for a period of three hours to form a homogeneous melt. After cooling, the glass was recovered from the crucible by crushing and was subsequently powdered mechanically with the help of mortar and pestle. This powder was used as the feed stock for plasma spheroidization using an indigenously developed 40 kW plasma spray system. Experiments were carried out at various operating parameters. The operating parameters were optimised to get spheroidised particles. The powder was sieved to get the required size range before irradiation.

  1. Preparation and characterization of an improved borosilicate glass matrix for the incorporation of high level radioactive waste (HAW). Pt. 1

    Guber, W.; Hussain, M.; Kahl, L.; Ondracek, G.; Saidl, J.; Dippel, T.

    1979-08-01

    On the basis of laboratory and technical experience with the preparation and the characterization of borosilicate glasses as solidification matrix for high level radioactive waste solution (HAW), a borosilicate glass composition with optimum properties has been developed. Keeping in view the technical and final storage requirements, a number of glass compositions with varying proportions of influential components as Al, Mg, Na were prepared and thoroughly investigated for certain parameters as specific gravity, thermal conductivity, impact resistance, thermal expansion, viscosity, characteristic temperature points, specific heat, evaporation losses from the melt, electrical conductivity, leach resistance, tendency toward recrystallization and second phase formation. All the compositions (some with different amounts of Gd 2 O 3 , an expected neutron poision) contained 15 wt. % simulated HAW oxides. Samples for investigation were fabricated very close to the actual process conditions of vitrification. Two glass products GP12 and GP26 (3.7% Gd 2 O 3 ) have been selected out of 25 glasses as the optimised products for further thorough investigations. Leach resistance, viscosity at 1420 K, tendency towards recrystallization and second phase formation were the most important deciding factors. (orig.) [de

  2. Demonstration of pyrometallurgical processing for metal fuel and HLW

    Tadafumi, Koyama; Kensuke, Kinoshita; Takatoshi, Hizikata; Tadashi, Inoue; Ougier, M.; Rikard, Malmbeck; Glatz, J.P.; Lothar, Koch

    2001-01-01

    CRIEPI and JRC-ITU have started a joint study on pyrometallurgical processing to demonstrate the capability of this type of process for separating actinide elements from spent fuel and HLW. The equipment dedicated for this experiments has been developed and installed in JRC-ITU. The stainless steel box equipped with tele-manipulators is operated under pure Ar atmosphere, and prepared for later installation in a hot cell. Experiments on pyro-processing of un-irradiated U-Pu-Zr metal alloy fuel by molten salt electrorefining has been carried out. Recovery of U and Pu from this type alloy fuel was first demonstrated with using solid iron cathode and liquid Cd cathode, respectively. (author)

  3. In vitro evaluation of borate-based bioactive glass scaffolds prepared by a polymer foam replication method

    Fu Hailuo; Fu Qiang; Zhou Nai; Huang Wenhai; Rahaman, Mohamed N.; Wang Deping; Liu Xin

    2009-01-01

    Borate-based bioactive glass scaffolds with a microstructure similar to that of human trabecular bone were prepared using a polymer foam replication method, and evaluated in vitro for potential bone repair applications. The scaffolds (porosity = 72 ± 3%; pore size = 250-500 μm) had a compressive strength of 6.4 ± 1.0 MPa. The bioactivity of the scaffolds was confirmed by the formation of a hydroxyapatite (HA) layer on the surface of the glass within 7 days in 0.02 M K 2 HPO 4 solution at 37 deg. C. The biocompatibility of the scaffolds was assessed from the response of cells to extracts of the dissolution products of the scaffolds, using assays of MTT hydrolysis, cell viability, and alkaline phosphatase activity. For boron concentrations below a threshold value (0.65 mM), extracts of the glass dissolution products supported the proliferation of bone marrow stromal cells, as well as the proliferation and function of murine MLO-A5 cells, an osteogenic cell line. Scanning electron microscopy showed attachment and continuous increase in the density of MLO-A5 cells cultured on the surface of the glass scaffolds. The results indicate that borate-based bioactive glass could be a potential scaffold material for bone tissue engineering provided that the boron released from the glass could be controlled below a threshold value.

  4. Electrochromic Glasses.

    1980-07-31

    this glass and that dipole-dipole correlations contribute to the "ferroelectric-like" character of this amorphous system. The TeO2 -W03 glasses can only...shows the dielectric constant and Fig. I(b) glass from pure TeO2 ot pure WO. In addition, glass the tan 8 of the WO glass as a function of temperature... glasses containing WO, in various glass forming nitworks of LifO-B1O0, Na:O-BzO,, and TeO2 were prepared from reagent grade oxides at 800 C - 9SO C in

  5. Crystallization in high-level waste glass: A review of glass theory and noteworthy literature

    Christian, J. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-08-01

    There is a fundamental need to continue research aimed at understanding nepheline and spinel crystal formation in high-level waste (HLW) glass. Specifically, the formation of nepheline solids (K/NaAlSiO₄) during slow cooling of HLW glass can reduce the chemical durability of the glass, which can cause a decrease in the overall durability of the glass waste form. The accumulation of spinel solids ((Fe, Ni, Mn, Zn)(Fe,Cr)₂O₄), while not detrimental to glass durability, can cause an array of processing problems inside of HLW glass melters. In this review, the fundamental differences between glass and solid-crystals are explained using kinetic, thermodynamic, and viscosity arguments, and several highlights of glass-crystallization research, as it pertains to high-level waste vitrification, are described. In terms of mitigating spinel in the melter and both spinel and nepheline formation in the canister, the complexity of HLW glass and the intricate interplay between thermal, chemical, and kinetic factors further complicates this understanding. However, new experiments seeking to elucidate the contributing factors of crystal nucleation and growth in waste glass, and the compilation of data from older experiments, may go a long way towards helping to achieve higher waste loadings while developing more efficient processing strategies.

  6. Preparation of glasses and glass ceramics of heavy metal oxides containing silver: optical, structural and electrochemical properties; Preparacao de vidros e vitroceramicas de oxidos de metais pesados contendo prata: propriedades opticas, estruturais e eletroquimicas

    Bregadiolli, Bruna A. [Departamento de Fisica, Faculdade de Ciencias, Universidade Estadual Paulista, Bauru - SP (Brazil); Souza, Ernesto R.; Sigoli, Fernando A. [Instituto de Quimica, Universidade Estadual de Campinas, Campinas - SP (Brazil); Caiut, Jose M.A. [Departamento de Quimica, Faculdade de Filosofia Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Ribeirao Preto - SP (Brazil); Alencar, Monica A.S.; Benedetti, Assis V. [Instituto de Quimica, Universidade Estadual Paulista, Araraquara - SP (Brazil); Nalin, Marcelo, E-mail: mnalin@ufscar.br [Departamento de Quimica, Universidade Federal de Sao Carlos, SP, (Brazil)

    2012-07-01

    Silver containing heavy metal oxide glasses and glass ceramics of the system WO{sub 3}-SbPO{sub 4} -PbO-AgCl with different AgCl contents have been prepared and their thermal, structural and optical properties characterized. Glass ceramics containing metallic silver nanoparticles have been prepared by annealing glass samples at temperatures above the glass transition and analyzed by transmission electron microscopy and energy dispersive X-ray microanalysis. The presence of the metallic clusters has been also confirmed by the observation of a surface plasmon resonance band in the visible range. Cyclic voltammetric measurements indicated the presence of metallic silver into the glasses, even before to perform the thermal treatment. (author)

  7. FINAL REPORT DM1200 TESTS WITH AZ 101 HLW SIMULANTS VSL-03R3800-4 REV 0 2/17/04

    KRUGER AA; MATLACK KS; BARDAKCI T; D' ANGELO NA; GONG W; KOT WK; PEGG IL

    2011-12-29

    This report documents melter and off-gas performance results obtained on the DM 1200 HLW Pilot Melter during processing of simulated HLW AZ-101 feed. The principal objectives of the DM1200 melter testing were to determine the achievable glass production rates for simulated HLW AZ-101 feed; determine the effect of bubbling rate and feed solids content on production rate; characterize melter off-gas emissions; characterize the performance of the prototypical off-gas system components as well as their integrated performance; characterize the feed, glass product, and off-gas effluents; and to perform pre- and post-test inspections of system components. The test objectives (including test success criteria), along with how they were met, are outlined in a table.

  8. Final Report DM1200 Tests With AZ 101 HLW Simulants VSL-03R3800-4, Rev. 0, 2/17/04

    Kruger, A.A.; Matlack, K.S.; Bardakci, T.; D'Angelo, N.A.; Gong, W.; Kot, W.K.; Pegg, I.L.

    2011-01-01

    This report documents melter and off-gas performance results obtained on the DM 1200 HLW Pilot Melter during processing of simulated HLW AZ-101 feed. The principal objectives of the DM1200 melter testing were to determine the achievable glass production rates for simulated HLW AZ-101 feed; determine the effect of bubbling rate and feed solids content on production rate; characterize melter off-gas emissions; characterize the performance of the prototypical off-gas system components as well as their integrated performance; characterize the feed, glass product, and off-gas effluents; and to perform pre- and post-test inspections of system components. The test objectives (including test success criteria), along with how they were met, are outlined in a table.

  9. Waste water purification using new porous ceramics prepared by recycling waste glass and bamboo charcoal

    Nishida, Tetsuaki; Morimoto, Akane; Yamamoto, Yoshito; Kubuki, Shiro

    2017-12-01

    New porous ceramics (PC) prepared by recycling waste glass bottle of soft drinks (80 mass%) and bamboo charcoal (20 mass%) without any binder was applied to the waste water purification under aeration at 25 °C. Artificial waste water (15 L) containing 10 mL of milk was examined by combining 15 mL of activated sludge and 750 g of PC. Biochemical oxygen demand (BOD) showed a marked decrease from 178 to 4.0 (±0.1) mg L-1 in 5 days and to 2.0 (±0.1) mg L-1 in 7 days, which was equal to the Environmental Standard for the river water (class A) in Japan. Similarly, chemical oxygen demand (COD) decreased from 158 to 3.6 (±0.1) mg L-1 in 5 days and to 2.2 (±0.1) mg L-1 in 9 days, which was less than the Environmental Standard for the Seawater (class B) in Japan: 3.0 mg L-1. These results prove the high water purification ability of the PC, which will be effectively utilized for the purification of drinking water, fish preserve water, fish farm water, etc.

  10. Preparation and characterization of new glasses from the TeO2-CdO-Al2O3-SiO2 system

    Zayas, Mª. E.; Espinoza-Beltrán, F. J.; Romero, Maximina; Rincón López, Jesús María

    1998-01-01

    A new family of glasses from the TeO2-CdO-Al2O3-SiO2 system obtained from CdS-TeO2 mixtures melted in fireclay crucibles have been prepared and characterized. The density values of these glasses are in the 3.30-3.46 gcm-3 range. The viscosity-temperature variation shows that glasses with high TeO2 content depict the typical variation of `short glasses' for a molding operation. Microstructural observations by TEM (replica method) and SEM microscopies have shown that these glasses contain very ...

  11. Surface treatment of glass substrates for the preparation of long-lived carbon stripper foils

    Takeuchi, Suehiro; Takekoshi, Eiko

    1981-02-01

    Glass substrates having uniformly distributed microscopic grains on the surfaces are useful to make long-lived carbon stripper foils for heavy ions. A method of surface treatment of glass substrates to form the surface structure is described. This method consists of precipitation of glass components, such as soda, onto the surfaces in a hot and humid atmosphere and a fogging treatment of forming microscopic grains of the precipitated substances. Some results of studies on the treatment conditions are also presented. (author)

  12. Strategic management of HLW repository projects

    Bartlett, J.W.

    1984-01-01

    This paper suggests an approach to strategic management of HLW repository projects based on the premise that a primary objective of project activities is resolution of issues. The approach would be implemented by establishing an issues management function with responsibility to define the issues agenda, develop and apply the tools for assessing progress toward issue resolution, and develop the issue resolution criteria. A principal merit of the approach is that it provides a defensible rationale for project plans and activities. It also helps avoid unnecessary costs and schedule delays, and it helps assure coordination between project functions that share responsibilities for issue resolution

  13. Effect of surfactant concentration on characteristics of mesoporous bioactive glass prepared by evaporation induced self-assembly process

    Shih, Chi-Chung; Chien, Chi-Sheng; Kung, Jung-Chang; Chen, Jian-Chih; Chang, Shy-Shin; Lu, Pei-Shan; Shih, Chi-Jen

    2013-01-01

    Highlights: ► All the unwanted organic contents were removed completely at temperatures above 600 °C. ► Specific surface area and pore volume of Mesoporous bioactive glasses reached maximum at the critical surfactant concentration. ► SAED pattern suggests that some glassy structures in the Bioactive Glasses became crystalline due to the heat treatment. ► The MBGs can induce the formation of an apatite-like layer on their surface in SBF, even after short soaking periods. - Abstract: Mesoporous bioactive glasses were prepared by the evaporation-induced self-assembly method. The main objective of the present study is to determine the effect of surfactant concentration on the synthesis of SiO 2 –CaO–P 2 O 5 mesoporous bioactive glasses; the characterization techniques used include X-ray diffraction, scanning electron microscopy and nitrogen adsorption and desorption isotherms. The results show that the specific surface area initially increased with increasing surfactant concentrations in the range of 2.1–9.1 wt% and significantly decreased from 328.7 to 204.0 m 2 /g in the concentration range of 9.1–12.5 wt%. For texture evaluation, the selected area electron diffraction patterns of the mesoporous bioactive glass precursor gels (9.1 wt% F127) calcined at different temperatures were analyzed; these patterns support the notion that some glassy structures in bioactive glasses become crystalline following heat treatment. The scanning electron microscopy images and X-ray diffraction patterns obtained agree with the inductively coupled plasma with atomic emission spectroscopy results as the mesoporous bioactive glasses can induce the formation of an apatite-like layer on their surface in SBF, even after short soaking periods.

  14. Effect of surfactant concentration on characteristics of mesoporous bioactive glass prepared by evaporation induced self-assembly process

    Shih, Chi-Chung [Department of Emergency Medicine, Chang Gung Memorial Hospital, Keelung, and Chang Gung University College of Medicine, Taoyuan, Taiwan (China); Department of Family Medicine, Chang Gung Memorial Hospital, Keelung, and Chang Gung University College of Medicine, Taoyuan, Taiwan (China); Chien, Chi-Sheng [Department of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan (China); Department of Orthopaedics, Chi Mei Foundation Hospital, Tainan, Taiwan (China); Department of Electrical Engineering, Southern Taiwan University of Science and Technology, Tainan, Taiwan (China); Kung, Jung-Chang [Department of Family Dentistry, Chung-Ho Memorial Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Chen, Jian-Chih [Department of Orthopaedics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Chang, Shy-Shin [Department of Emergency Medicine, Chang Gung Memorial Hospital, Taoyuan, and Chang Gung University College of Medicine, Taoyuan, Taiwan (China); Department of Family Medicine, Chang Gung Memorial Hospital, Taoyuan, and Chang Gung University College of Medicine, Taoyuan, Taiwan (China); Lu, Pei-Shan [Department of Fragrance and Cosmetic Science, Kaohsiung Medical University, 100 Shi-Chuan 1st Road, Kaohsiung 80708, Taiwan (China); Shih, Chi-Jen, E-mail: cjshih@kmu.edu.tw [Department of Fragrance and Cosmetic Science, Kaohsiung Medical University, 100 Shi-Chuan 1st Road, Kaohsiung 80708, Taiwan (China)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer All the unwanted organic contents were removed completely at temperatures above 600 Degree-Sign C. Black-Right-Pointing-Pointer Specific surface area and pore volume of Mesoporous bioactive glasses reached maximum at the critical surfactant concentration. Black-Right-Pointing-Pointer SAED pattern suggests that some glassy structures in the Bioactive Glasses became crystalline due to the heat treatment. Black-Right-Pointing-Pointer The MBGs can induce the formation of an apatite-like layer on their surface in SBF, even after short soaking periods. - Abstract: Mesoporous bioactive glasses were prepared by the evaporation-induced self-assembly method. The main objective of the present study is to determine the effect of surfactant concentration on the synthesis of SiO{sub 2}-CaO-P{sub 2}O{sub 5} mesoporous bioactive glasses; the characterization techniques used include X-ray diffraction, scanning electron microscopy and nitrogen adsorption and desorption isotherms. The results show that the specific surface area initially increased with increasing surfactant concentrations in the range of 2.1-9.1 wt% and significantly decreased from 328.7 to 204.0 m{sup 2}/g in the concentration range of 9.1-12.5 wt%. For texture evaluation, the selected area electron diffraction patterns of the mesoporous bioactive glass precursor gels (9.1 wt% F127) calcined at different temperatures were analyzed; these patterns support the notion that some glassy structures in bioactive glasses become crystalline following heat treatment. The scanning electron microscopy images and X-ray diffraction patterns obtained agree with the inductively coupled plasma with atomic emission spectroscopy results as the mesoporous bioactive glasses can induce the formation of an apatite-like layer on their surface in SBF, even after short soaking periods.

  15. Demonstration of the Defense Waste Processing Facility vitrification process for Tank 42 radioactive sludge -- Glass preparation and characterization

    Bibler, N.E.; Fellinger, T.L.; Marshall, K.M.; Crawford, C.L.; Cozzi, A.D.; Edwards, T.B.

    1999-01-01

    The Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) is currently processing and immobilizing the radioactive high level waste sludge at SRS into a durable borosilicate glass for final geological disposal. The DWPF has recently finished processing the first radioactive sludge batch, and is ready for the second batch of radioactive sludge. The second batch is primarily sludge from Tank 42. Before processing this batch in the DWPF, the DWPF process flowsheet has to be demonstrated with a sample of Tank 42 sludge to ensure that an acceptable melter feed and glass can be made. This demonstration was recently completed in the Shielded Cells Facility at SRS. An earlier paper in these proceedings described the sludge composition and processes necessary for producing an acceptable melter fee. This paper describes the preparation and characterization of the glass from that demonstration. Results substantiate that Tank 42 sludge after mixing with the proper amount of glass forming frit (Frit 200) can be processed to make an acceptable glass

  16. Glass formulation for phase 1 high-level waste vitrification

    Vienna, J.D.; Hrma, P.R.

    1996-04-01

    The purpose of this study is to provide potential glass formulations for prospective Phase 1 High-Level Waste (HLW) vitrification at Hanford. The results reported here will be used to aid in developing a Phase 1 HLW vitrification request for proposal (RFP) and facilitate the evaluation of ensuing proposals. The following factors were considered in the glass formulation effort: impact on total glass volume of requiring the vendor to process each of the tank compositions independently versus as a blend; effects of imposing typical values of B 2 O 3 content and waste loading in HLW borosilicate glasses as restrictions on the vendors (according to WAPS 1995, the typical values are 5--10 wt% B 2 O 3 and 20--40 wt% waste oxide loading); impacts of restricting the processing temperature to 1,150 C on eventual glass volume; and effects of caustic washing on any of the selected tank wastes relative to glass volume

  17. Preparation and Characterization of UPR/ LNR/ Glass Fiber Composite by using Unsaturated Polyester Resin (PET) from PET Wastes

    Siti Farhana Hisham; Ishak Ahmad; Rusli Daik

    2011-01-01

    UPR/ LNR/ glass fibre composite had been prepared by using unsaturated polyester resin (UPR) based from recycled PET product. PET waste was recycled by glycolysis process and the glycides product was then reacted with maleic anhydride to produce unsaturated polyester resin. The preparation of UPR/ LNR blends were conducted by varying the amount of LNR addition to the resin ranging from 0-7.5 % (wt). The composition of UPR/LNR blend with good mechanical properties had been selected as a matrix of the glass fiber reinforced composite. Glass fibre was also treated by (3-Amino propil)triethoxysilane as a coupling agent. From the result, the addition of 2.5 % LNR in UPR had showed the optimum mechanical and morphological properties where the elastomer particle's were well dispersed in the matrix with smaller size. The silane treatment on the glass fiber increased the tensile and impact strength values of the UPR/ LNR/ GF composite compared to untreated fiber reinforcement. (author)

  18. Glass Property Data and Models for Estimating High-Level Waste Glass Volume

    Vienna, John D.; Fluegel, Alexander; Kim, Dong-Sang; Hrma, Pavel R.

    2009-10-05

    This report describes recent efforts to develop glass property models that can be used to help estimate the volume of high-level waste (HLW) glass that will result from vitrification of Hanford tank waste. The compositions of acceptable and processable HLW glasses need to be optimized to minimize the waste-form volume and, hence, to save cost. A database of properties and associated compositions for simulated waste glasses was collected for developing property-composition models. This database, although not comprehensive, represents a large fraction of data on waste-glass compositions and properties that were available at the time of this report. Glass property-composition models were fit to subsets of the database for several key glass properties. These models apply to a significantly broader composition space than those previously publised. These models should be considered for interim use in calculating properties of Hanford waste glasses.

  19. Glass Property Data and Models for Estimating High-Level Waste Glass Volume

    Vienna, John D.; Fluegel, Alexander; Kim, Dong-Sang; Hrma, Pavel R.

    2009-01-01

    This report describes recent efforts to develop glass property models that can be used to help estimate the volume of high-level waste (HLW) glass that will result from vitrification of Hanford tank waste. The compositions of acceptable and processable HLW glasses need to be optimized to minimize the waste-form volume and, hence, to save cost. A database of properties and associated compositions for simulated waste glasses was collected for developing property-composition models. This database, although not comprehensive, represents a large fraction of data on waste-glass compositions and properties that were available at the time of this report. Glass property-composition models were fit to subsets of the database for several key glass properties. These models apply to a significantly broader composition space than those previously publised. These models should be considered for interim use in calculating properties of Hanford waste glasses.

  20. Investigations into the stabilisation of drugs by sugar glasses : I. Tablets prepared from stabilised alkaline phosphatase

    Eriksson, H.J.C.; Hinrichs, W.L.J.; van Veen, B.; Somsen, G.W.; de Jong, G.J.; Frijlink, H.W.

    2002-01-01

    The aim of this study was to investigate the formulation of sugar glass stabilised alkaline phosphatase from bovine intestine (BIAP) into tablets. Two major subjects of tablet formulation were investigated. First, the compaction behaviour of the inulin sugar glass was investigated. Secondly, the

  1. Preparation of. beta. -spodumene glass-ceramics from blast furnace slag. Koro slag wo genryo to shita. beta. -spodumene kei kesshoka glass no seizo

    Wang, M. (National Kaoshing Institute Technology, Kaoshiung (Rep. of China)); Hon, M. (National Cheng Kung University, Tainan (Rep. of China))

    1990-07-01

    Li {sub 2} O-CaO-Al {sub 2} O {sub 3} -SiO {sub 2} (LCAS) glass-ceramics were prepared from blast furnace slag by quenching in water after heating at 1,450 {degree} C for 3 hours. Blast furnace slag (40.0wt%) containing CaO, MgO, Al {sub 2} O {sub 3} and SiO {sub 2} as major components was used as a raw material, and batch compositions were modified by mixing blast furnace slag with Al {sub 2} O {sub 3}, SiO {sub 2} and Li {sub 2} CO {sub 3}, and a nucleating agent TiO {sub 2}. The A specimen with TiO {sub 2} of 7.4wt% and B specimen with 4.6wt% were prepared, and the crystallization process of the glass was examined with X-ray diffraction, electron diffraction and so forth. As a result, a major crystalline phase was {beta} -spodumene (Li {sub 2} O-Al {sub 2} O {sub 3} -4SiO {sub 2}), and the average thermal expansion coefficients of A and B were 40.1 and 47.2 {times} 10 {sup {minus} 7} / {degree} C in the temperature range from 25 to 700 {degree} C, respectively. A small amount of titanite was also observed in A as a sub-phase. 14 refs., 5 figs., 3 tabs.

  2. Effects of beta/gamma radiation on nuclear waste glasses

    Weber, W.J. [Pacific Northwest National Lab., Richland, WA (United States)

    1997-07-01

    A key challenge in the disposal of high-level nuclear waste (HLW) in glass waste forms is the development of models of long-term performance based on sound scientific understanding of relevant phenomena. Beta decay of fission products is one source of radiation that can impact the performance of HLW glasses through the interactions of the emitted {beta}-particles and g-rays with the atoms in the glass by ionization processes. Fused silica, alkali silicate glasses, alkali borosilicate glasses, and nuclear waste glasses are all susceptible to radiation effects from ionization. In simple glasses, defects (e.g., non-bridging oxygen and interstitial molecular oxygen) are observed experimentally. In more complex glasses, including nuclear waste glasses, similar defects are expected, and changes in microstructure, such as the formation of bubbles, have been reported. The current state of knowledge regarding the effects of {beta}/{gamma} radiation on the properties and microstructure of nuclear waste glasses are reviewed. (author)

  3. Effects of beta/gamma radiation on nuclear waste glasses

    Weber, W.J.

    1997-01-01

    A key challenge in the disposal of high-level nuclear waste (HLW) in glass waste forms is the development of models of long-term performance based on sound scientific understanding of relevant phenomena. Beta decay of fission products is one source of radiation that can impact the performance of HLW glasses through the interactions of the emitted β-particles and g-rays with the atoms in the glass by ionization processes. Fused silica, alkali silicate glasses, alkali borosilicate glasses, and nuclear waste glasses are all susceptible to radiation effects from ionization. In simple glasses, defects (e.g., non-bridging oxygen and interstitial molecular oxygen) are observed experimentally. In more complex glasses, including nuclear waste glasses, similar defects are expected, and changes in microstructure, such as the formation of bubbles, have been reported. The current state of knowledge regarding the effects of β/γ radiation on the properties and microstructure of nuclear waste glasses are reviewed. (author)

  4. Grouping in partitioning of HLW for burning and/or transmutation with nuclear reactors

    Kitamoto, Asashi; Mulyanto.

    1995-01-01

    A basic concept on partitioning and transmutation treatment by neutron reaction was developed in order to improve the waste management and the disposal scenario of high level waste (HLW). The grouping in partitioning was important factor and closely linked with the characteristics of B/T (burning and/or transmutation) treatment. The selecting and grouping concept in partitioning of HLW was proposed herein, such as Group MA1 (Np, Am, and unrecovered U and Pu), Group MA2 (Cm, Cf etc.), Group A (Tc and I), Group B (Cs and Sr) and Group R (the partitioned remain of HLW), judging from the three criteria for B/T treatment proposed in this study, which is related to (1) the value of hazard index for long-term tendency based on ALI, (2) the relative dose factor related to the mobility or retardation in ground water penetrated through geologic layer, and (3) burning and/or transmutation characteristics for recycle B/T treatment and the decay acceleration ratio by neutron reaction. Group MA1 and Group A could be burned effectively by thermal B/T reactor. Group MA2 could be burned effectively by fast B/T reactor. Transmutation of Group B by neutron reaction is difficult, therefore the development of radiation application of Group B (Cs and Sr) in industrial scale may be an interesting option in the future. Group R, i.e. the partitioned remains of HLW, and also a part of Group B should be immobilized and solidified by the glass matrix. HI ALI , the hazard index based on ALI, due to radiotoxicity of Group R can be lower than HI ALI due to standard mill tailing (smt) or uranium ore after about 300 years. (author)

  5. Studies on the immobilization of simulated HLW in NaTi2(PO4)3 (NTP) matrix

    Raja Madhavan, R.; Govindan Kutty, K.V.; Gandhi, A.S.

    2015-01-01

    Immobilization of high level nuclear waste (HLW) is a big challenge faced by the nuclear industry today. The HLW has to be contained and isolated from the biosphere for geological timescales. NZP family of compounds is very versatile monophasic hosts for HLW immobilization. Their crystal structure can accommodate nearly all the cations known to be present in HLW due to its open structure with voids of different size. In the present study a systematic investigation on NaTi 2 (PO 4 ) 3 belonging to the NZP family; as a potential host for HLW immobilization was carried out. A simulated HLW expected from Fast Breeder Test Reactor, India (FBTR) (150Gwd/T burnup, 1 year cooling) was used. Simulated NTP waste forms with 5, 10, 15 wt. % waste loading were prepared by employing a wet chemical method and characterized. Single phase simulated NTP waste forms with up to 5 wt.% waste loading could be prepared for samples sintered in air and above 5 wt.% waste loading, monazite phase is observed as a minor secondary phase. It was found that when sintering is done in Ar/10%H 2 , NTP matrix accepts up to 10 wt.% waste loading without formation of any second phase. From the SEM studies, it was observed that samples sintered in air as well as Ar/10%H 2 palladium segregated as a metal phase and uniformly distributed throughout the waste matrix. The elemental mapping revealed retention of some of the fission products like Ru, Mo, Cs that are volatile during sintering above 1173 K and are homogenously distributed in the matrix. (author)

  6. A method for preparing a sintered glass powder for manufacturing microspheres

    Budrick, R.G.; King, F.T.; Nolen, R.L. Jr.; Solomon, D.E.

    1975-01-01

    The invention relates to the manufacture of sintered glass-powder. It relates to a method comprising the step of forming a vitreous gel so that it contains an occluded substance adapted to expand when heated, said gel being subsequently dried, then crushed and sorted prior to being washed and dried again. Application to the manufacture of sintered glass-powder for forming microspheres adapted to contain a thermonuclear fuel [fr

  7. Comparison of Microleakage of Glass Ionomer Restoration in Primary Teeth Prepared by Er: YAG Laser and the Conventional Method

    M. Ghandehari

    2012-01-01

    Full Text Available Objective: One of the main criteria in evaluating the restorative materials is the degree of microleakage. The aim of this study was to compare the microleakage of glass ionomer restored cavities prepared by Er:YAG laser or turbine and bur.Materials and Methods: Twenty extracted caries-free deciduous posterior teeth were selected for this study. The teeth were randomly divided into two groups for cavity preparation. Cavities in group one were prepared by high speed turbine and bur. In the second group, Er:YAG laser with a 3W output power, 300 mJ energy and 10 Hz frequency was used. Cavities were restored with GC Fuji II LC. After thermocycling, the samples were immersed into 0.5% methylene blue solution. They were sectioned for examination under optic microscope.Results: The Wilcoxon signed ranks test showed no significant difference between microleakage of the laser group and the conventional group (P>0.05.Conclusion: Er:YAG laser with its advantages in pediatric dentistry may be suggested as an alternative device for cavity preparation.Key Words: Er:YAG laser, Glass ionomer, Microleakage

  8. HLW Long-term Management Technology Development

    Choi, Jong Won; Kang, C. H.; Ko, Y. K.

    2010-02-01

    Permanent disposal of spent nuclear fuels from the power generation is considered to be the unique method for the conservation of human being and nature in the present and future. In spite of spent nuclear fuels produced from power generation, based on the recent trends on the gap between supply and demand of energy, the advance on energy price and reduction of carbon dioxide, nuclear energy is expected to play a role continuously in Korea. It means that a new concept of nuclear fuel cycle is needed to solve problems on spent nuclear fuels. The concept of the advanced nuclear fuel cycle including PYRO processing and SFR was presented at the 255th meeting of the Atomic Energy Commission. According to the concept of the advanced nuclear fuel cycle, actinides and long-term fissile nuclides may go out of existence in SFR. And then it is possible to dispose of short term decay wastes without a great risk bearing. Many efforts had been made to develop the KRS for the direct disposal of spent nuclear fuels in the representative geology of Korea. But in the case of the adoption of Advanced nuclear fuel cycle, the disposal of PYRO wastes should be considered. For this, we carried out the Safety Analysis on HLW Disposal Project with 5 sub-projects such as Development of HLW Disposal System, Radwaste Disposal Safety Analysis, Feasibility study on the deep repository condition, A study on the Nuclide Migration and Retardation Using Natural Barrier, and In-situ Study on the Performance of Engineered Barriers

  9. Preparation of starch-g-polyacrylamide and its utilization as an adhesive for wood, paper and glass

    Abu-Ayana, Y.M.; Abou Zeid, N.Y.; Asran, A.Sh.; Aly, A.S.

    2005-01-01

    Starch- based adhesives are capable of wetting polar surfaces such as cellulose, penetrating pores, and forming strong bonds through mechanical and physical bonds. This paper studies the modification of starch by grafting with acrylamide, and the relation between modification and adhesion properties. Six formulae are prepared from modified and unmodified starch, and evaluated as adhesives for wood, glass, carton, and paper. Study of the factors affecting the adhesive bond is performed. Promising results are obtained. The adhesive formulae I-VI can be used successfully as paper and carton adhesives. Formulae I, TI and III can be used as wood adhesives. Excellent value for shear strength using formula No. I, comparable with other known thermoplastic and thermoset adhesives., formula I also can be used as glass adhesive, but in narrow applications and in absence of water

  10. Near-infrared optical properties of Yb3+-doped silicate glass waveguides prepared by double-energy proton implantation

    Shen, Xiao-Liang; Zhu, Qi-Feng; Zheng, Rui-Lin; Lv, Peng; Guo, Hai-Tao; Liu, Chun-Xiao

    2018-03-01

    We report on the preparation and properties of an optical planar waveguide structure operating at 1539 nm in the Yb3+-doped silicate glass. The waveguide was formed by using (470 + 500) keV proton implantation at fluences of (1.0 + 2.0) × 1016 ions/cm2. The waveguiding characteristics including the guided-mode spectrum and the near-field image were investigated by the m-line technique and the finite-difference beam propagation method. The energy distribution for implanted protons and the refractive index profile for the proton-implanted waveguide were simulated by the stopping and range of ions in matter and the reflectivity calculation method. The proton-implanted Yb3+-doped silicate glass waveguide is a candidate for optoelectronic elements in the near-infrared region.

  11. HLW disposal in Germany - R and D achievements and outlook

    Steininger, W.

    2006-01-01

    The paper gives a brief overview of the status of R and D on HLW disposal. Shortly addressed is the current nuclear policy. After describing the responsibilities regarding R and D for disposing of heat-generating high-level (HLW) waste (vitrified waste and spent fuel), selected projects are mentioned to illustrate the state of knowledge in disposing of waste in rock salt. Participation in international projects and programs is described to illustrate the value for the German concepts and ideas for HLW disposal in different rock types. Finally, a condensed outlook on future activities is given. (author)

  12. Preparation and characterization of physically modified glass beads used as model carriers in dry powder inhalers.

    Zellnitz, Sarah; Redlinger-Pohn, Jakob Dominik; Kappl, Michael; Schroettner, Hartmuth; Urbanetz, Nora Anne

    2013-04-15

    The aim of this work is the physical modification and characterization of the surface topography of glass beads used as model carriers in dry powder inhalers (DPIs). By surface modification the contact area between drug and carrier and thereby interparticle forces may be modified. Thus the performance of DPIs that relies on interparticle interactions may be improved. Glass beads were chosen as model carriers because various prospects of physical surface modification may be applied without affecting other factors also impacting interparticle interactions like particle size and shape. To generate rough surfaces glass beads were processed mechanically by friction and impaction in a ball mill with different grinding materials that were smaller and harder with respect to the glass beads. By varying the grinding time (4 h, 8 h) and by using different grinding media (tungsten carbide, quartz) surfaces with different shades of roughness were generated. Depending on the hardness of the grinding material and the grinding time the surface roughness was more or less pronounced. Surface roughness parameters and specific surface area were determined via several complementary techniques in order to get an enhanced understanding of the impact of the modifying procedure on the surface properties of the glass beads. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. The characterization of ceramic alumina prepared by using additive glass beads

    Suprapedi; Muljadi; Sardjono, Priyo

    2018-01-01

    The ceramic alumina has been made by using additive glass bead (5 and 10 % wt.). There are two kinds of materials, such as : gamma Alumina and glass bead. Synthesis of alumina was done by ball milling for 24 hours, then the mixed powder was dried in drying oven at 100 °C for 6 hours. Furthermore, the dried powder was mixed by using 2 % of PVA and continued with compacted to form a pellet with pressure of 50 MPA. The next step is sintering process with variation temperature of 1150, 1200, 1250, 1300 and 1400 °C and holding time for 2 hours. The characterization conducted are consist of test density, hardness, shrinkage, and microstructure. The results show that ceramic alumina with addition of 10 % wt. glass bead has the higher value of density, hardness and shrinkage than addition of 5% wt. glass bead. The highest characterization of ceramic alumina with addition 10 % glass bead was achieved at sintering temperature of 1400 °C with density 3.68 g/cm3, hardness vickers 780.40 Hv and shrinkage 15.23 %. The XRD results show that it was founds a corrundum (alpha Alumina) as dominant phase and mullite as minor phase.

  14. Preparation and biocompatibility evaluation of apatite/wollastonite-derived porous bioactive glass ceramic scaffolds

    Zhang Hua; Ye Xiaojian; Li Jiashun

    2009-01-01

    An apatite/wollastonite-derived (A/W) porous glass ceramic scaffold with highly interconnected pores was successfully fabricated by adding a plastic porosifier. The morphology, porosity and mechanical strength were characterized. The results showed that the glass ceramic scaffold with controllable pore size and porosity displayed open macropores. In addition, good in vitro bioactivity was found for the scaffold obtained by soaking it in simulated body fluid. Mesenchymal stem cells (MSCs) were cultured, expanded and seeded on the scaffold, and the adhesion and proliferation of MSCs were determined using MTT assay and environmental scanning electron microscopy (ESEM). The results revealed that the scaffold was biocompatible and had no negative effects on the MSCs in vitro. The in vivo biocompatibility and osteogenicity were investigated by implanting both the pure scaffold and the MSC/scaffold construct in rabbit mandibles and studying histologically. The results showed that the glass ceramic scaffold exhibited good biocompatibility and osteoconductivity. Moreover, the introduction of MSCs into the scaffold observably improved the efficiency of new bone formation, especially at the initial stage after implantation. However, the glass ceramic scaffold showed the same good biocompatibility and osteogenicity as the hybrid one at the later stage. These results indicate that porous bioactive scaffolds based on the original apatite-wollastonite glass ceramic fulfil the basic requirements of a bone tissue engineering scaffold.

  15. Enamels in stained glass windows: Preparation, chemical composition, microstructure and causes of deterioration

    Schalm, O.; Van der Linden, V.; Frederickx, P.; Luyten, S.; Van der Snickt, G.; Caen, J.; Schryvers, D.; Janssens, K.; Cornelis, E.; Van Dyck, D.; Schreiner, M.

    2009-01-01

    Stained glass windows incorporating dark blue and purple enamel paint layers are in some cases subject to severe degradation while others from the same period survived the ravages of time. A series of dark blue, green-blue and purple enamel glass paints from the same region (Northwestern Europe) and from the same period (16-early 20th centuries) has been studied by means of a combination of microscopic X-ray fluorescence analysis, electron probe micro analysis and transmission electron microscopy with the aim of better understanding the causes of the degradation. The chemical composition of the enamels diverges from the average chemical composition of window glass. Some of the compositions appear to be unstable, for example those with a high concentration of K 2 O and a low content of CaO and PbO. In other cases, the deterioration of the paint layers was caused by the less than optimal vitrification of the enamel during the firing process. Recipes and chemical compositions indicate that glassmakers of the 16-17th century had full control over the color of the enamel glass paints they made. They mainly used three types of coloring agents, based on Co (dark blue), Mn (purple) and Cu (light-blue or green-blue) as coloring elements. Blue-purple enamel paints were obtained by mixing two different coloring agents. The coloring agent for red-purple enamel, introduced during the 19th century, was colloidal gold embedded in grains of lead glass.

  16. Preparation and characterization of a PbO protective glass; Elaboration et caracterisation d un verre protecteur a base de PbO

    Ayadi, Azzedine; Stiti, Nacera; Benaissa, Abdelazeze [Laboratoire des materiaux mineraux et composites, Faculte des sciences de l ingenieur - Universite de Boumerdes - 35000 Boumerdes - (Algeria); Palou, Martin [Departement ceramique et verre, Faculte de chimie, Universite de Bratislava - (Slovakia)

    2006-07-01

    The study of the binary system of lead silicate glass PbO-SiO{sub 2}, and particularly the glasses having more than 80% of PbO and no alkaline oxides allows to answer to some preoccupations and requirements towards these glasses, in particular their transparencies and their attenuation power, on account of the high values of the refractive index and the density of these glasses. Radiation protection is a field which concerns all the countries of the world including Algeria; this country is then concerned by the import of this product used in hospitals for instance. On account of the importance of this glass and of its wide application domain, it is interesting to study it in order to be able to manufacture it in Algeria and to improve its properties. The aim of this work is then to prepare different lead silicate glasses allowing a maximal absorption of the ionizing radiations. (O.M.)

  17. Novel selenium containing boro-phosphate glasses: Preparation and structural study

    Ciceo-Lucacel, R.; Radu, T.; Ponta, O.; Simon, V.

    2014-01-01

    We synthesized a new boro-phosphate glass system with different %mol SeO 2 content by conventional melt quenching technique. All samples were obtained in a glassy state with the vitreous structure confirmed by X-ray diffraction analysis. Scanning electron microscopy (SEM) revealed some non-homogeneous domains on the glasses surface, and their tendency to link each other once the selenium oxide content increases. Energy-dispersive X-ray analysis (EDAX) indicated similar elemental composition in different regions of each sample. X-ray photoelectron spectroscopy (XPS) was used to determine the nature of chemical bonding and the elemental composition at the sample surfaces, and Fourier transform infrared (FT-IR) spectroscopy was used to determine the structural groups in the obtained glass structure. Based on FT-IR results, the glass structure at short range order consists mainly of small phosphate units such as pyrophosphate (i.e. P 2 O 7 4− dimmers or terminating groups at the end of phosphate chains) and some metaphosphate (i.e. PO 3 − middle groups in the phosphate chains) units. The boron atoms are mainly placed in three-coordinated sites in BØ 3 or BØ 2 O − units. A small contribution of BØ 4 − units was also detected from the FT-IR spectra of glasses. For SeO 2 content higher than 5 mol%, the modifier role of selenium ions is strongly reflected on the local structure dominated in this case by pyrophosphate units. - Highlights: • New P 2 O 5 -CaO-B 2 O 3 -SeO 2 glasses synthesized by conventional melt quenching method. • Evidences for the Se ions modifier role in the local structure by FT-IR and XPS. • Significant advances in understanding the structural properties of the new system

  18. Preparation and Characterization of Lightweight Mullite-Silica Rich Glass Aggregates

    Nan Li

    2011-09-01

    Full Text Available Phase compositions, microstructures and properties of four lightweight mullite-silica rich glass aggregates with high strength were investigated by X-ray diffractometry (XRD, scanning electron microscopy (SEM, and FactSage 6.2 software. It was found that the lightweight aggregates with higher Al2O3 content had higher mullite content, porosity and larger mullite crystallites, but lower content and viscosity of melt at elevated temperature. Most of Fe2O3 and TiO2 were incorporated in mullite and most of K2O and Na2O were in glass to reduce viscosity of melt at elevated temperature.

  19. Final Report Integrated DM1200 Melter Testing Using AZ-102 And C-106/AY-102 HLW Simulants: HLW Simulant Verification VSL-05R5800-1, Rev. 0, 6/27/05

    Kruger, A.A.; Matlack, K.S.; Gong, W.; Bardakci, T.; D'Angelo, N.A.; Brandys, M.; Kot, W.K.; Pegg, I.L.

    2011-01-01

    The principal objectives of the DM1200 melter tests were to determine the effects of feed rheology, feed solid content, and bubbler configuration on glass production rate and off-gas system performance while processing the HLW AZ-101 and C-106/AY-102 feed compositions; characterize melter off-gas emissions; characterize the performance of the prototypical off-gas system components, as well as their integrated performance; characterize the feed, glass product, and off-gas effluents; and perform pre- and post test inspections of system components. The specific objectives (including test success criteria) of this testing, along with how each objective was met, are outlined in a table. The data provided in this Final Report address the impacts of HLW melter feed rheology on melter throughput and validation of the simulated HLW melter feeds. The primary purpose of this testing is to further validate/verify the HLW melter simulants that have been used for previous melter testing and to support their continued use in developing melter and off-gas related processing information for the Project. The primary simulant property in question is rheology. Simulants and melter feeds used in all previous melter tests were produced by direct addition of chemicals; these feed tend to be less viscous than rheological the upper-bound feeds made from actual wastes. Data provided here compare melter processing for the melter feed used in all previous DM100 and DM1200 tests (nominal melter feed) with feed adjusted by the feed vendor (NOAH Technologies) to be more viscous, thereby simulating more closely the upperbounding feed produced from actual waste. This report provides results of tests that are described in the Test Plan for this work. The Test Plan is responsive to one of several test objectives covered in the WTP Test Specification for this work; consequently, only part of the scope described in the Test Specification was addressed in this particular Test Plan. For the purpose of

  20. FINAL REPORT INTEGRATED DM1200 MELTER TESTING USING AZ 102 AND C 106/AY-102 HLW SIMULANTS: HLW SIMULANT VERIFICATION VSL-05R5800-1 REV 0 6/27/05

    KRUGER AA; MATLACK KS; GONG W; BARDAKCI T; D' ANGELO NA; BRANDYS M; KOT WK; PEGG IL

    2011-12-29

    The principal objectives of the DM1200 melter tests were to determine the effects of feed rheology, feed solid content, and bubbler configuration on glass production rate and off-gas system performance while processing the HLW AZ-101 and C-106/AY-102 feed compositions; characterize melter off-gas emissions; characterize the performance of the prototypical off-gas system components, as well as their integrated performance; characterize the feed, glass product, and off-gas effluents; and perform pre- and post test inspections of system components. The specific objectives (including test success criteria) of this testing, along with how each objective was met, are outlined in a table. The data provided in this Final Report address the impacts of HLW melter feed rheology on melter throughput and validation of the simulated HLW melter feeds. The primary purpose of this testing is to further validate/verify the HLW melter simulants that have been used for previous melter testing and to support their continued use in developing melter and off-gas related processing information for the Project. The primary simulant property in question is rheology. Simulants and melter feeds used in all previous melter tests were produced by direct addition of chemicals; these feed tend to be less viscous than rheological the upper-bound feeds made from actual wastes. Data provided here compare melter processing for the melter feed used in all previous DM100 and DM1200 tests (nominal melter feed) with feed adjusted by the feed vendor (NOAH Technologies) to be more viscous, thereby simulating more closely the upperbounding feed produced from actual waste. This report provides results of tests that are described in the Test Plan for this work. The Test Plan is responsive to one of several test objectives covered in the WTP Test Specification for this work; consequently, only part of the scope described in the Test Specification was addressed in this particular Test Plan. For the purpose of

  1. WTP Waste Feed Qualification: Glass Fabrication Unit Operation Testing Report

    Stone, M. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL). Hanford Missions Programs; Newell, J. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL). Process Technology Programs; Johnson, F. C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL). Engineering Process Development; Edwards, T. B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL). Engineering Process Development

    2016-07-14

    The waste feed qualification program is being developed to protect the Hanford Tank Waste Treatment and Immobilization Plant (WTP) design, safety basis, and technical basis by assuring waste acceptance requirements are met for each staged waste feed campaign prior to transfer from the Tank Operations Contractor to the feed receipt vessels inside the Pretreatment Facility. The Waste Feed Qualification Program Plan describes the three components of waste feed qualification: 1. Demonstrate compliance with the waste acceptance criteria 2. Determine waste processability 3. Test unit operations at laboratory scale. The glass fabrication unit operation is the final step in the process demonstration portion of the waste feed qualification process. This unit operation generally consists of combining each of the waste feed streams (high-level waste (HLW) and low-activity waste (LAW)) with Glass Forming Chemicals (GFCs), fabricating glass coupons, performing chemical composition analysis before and after glass fabrication, measuring hydrogen generation rate either before or after glass former addition, measuring rheological properties before and after glass former addition, and visual observation of the resulting glass coupons. Critical aspects of this unit operation are mixing and sampling of the waste and melter feeds to ensure representative samples are obtained as well as ensuring the fabrication process for the glass coupon is adequate. Testing was performed using a range of simulants (LAW and HLW simulants), and these simulants were mixed with high and low bounding amounts of GFCs to evaluate the mixing, sampling, and glass preparation steps in shielded cells using laboratory techniques. The tests were performed with off-the-shelf equipment at the Savannah River National Laboratory (SRNL) that is similar to equipment used in the SRNL work during qualification of waste feed for the Defense Waste Processing Facility (DWPF) and other waste treatment facilities at the

  2. Anomalous dissolution behaviour of tablets prepared from sugar glass-based solid dispersions

    Van Drooge, D.J.; Hinrichs, W.L.J.; Frijlink, H.W.

    2004-01-01

    In this study, anomalous dissolution behaviour of tablets consisting of sugar glass dispersions was investigated. The poorly aqueous soluble diazepam was used as a lipophilic model drug. The release of diazepam and sugar carrier was determined to study the mechanisms governing dissolution behaviour.

  3. Properties of sintered glass-ceramics prepared from plasma vitrified air pollution control residues

    Roether, J.A.; Daniel, D.J. [Department of Materials, Imperial College London, London SW7 2AZ (United Kingdom); Amutha Rani, D. [Department of Materials, Imperial College London, London SW7 2AZ (United Kingdom); Department of Civil and Environmental Engineering, Imperial College London, London SW7 2AZ (United Kingdom); Deegan, D.E. [Tetronics Ltd., Swindon, Wiltshire SN3 4DE (United Kingdom); Cheeseman, C.R., E-mail: c.cheeseman@imperial.ac.uk [Department of Civil and Environmental Engineering, Imperial College London, London SW7 2AZ (United Kingdom); Boccaccini, A.R., E-mail: a.boccaccini@imperial.ac.uk [Department of Materials, Imperial College London, London SW7 2AZ (United Kingdom)

    2010-01-15

    Air pollution control (APC) residues, obtained from a major UK energy from waste (EfW) plant, processing municipal solid waste, have been blended with silica and alumina and melted using DC plasma arc technology. The glass produced was crushed, milled, uni-axially pressed and sintered at temperatures between 750 and 1150 deg. C, and the glass-ceramics formed were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Mechanical properties assessed included Vickers's hardness, flexural strength, Young's modulus and thermal shock resistance. The optimum sintering temperature was found to be 950 deg. C. This produced a glass-ceramic with high density ({approx}2.58 g/cm{sup 3}), minimum water absorption ({approx}2%) and relatively high mechanical strength ({approx}81 {+-} 4 MPa). Thermal shock testing showed that 950 deg. C sintered samples could withstand a 700 deg. C quench in water without micro-cracking. The research demonstrates that glass-ceramics can be readily formed from DC plasma treated APC residues and that these have comparable properties to marble and porcelain. This novel approach represents a technically and commercially viable treatment option for APC residues that allow the beneficial reuse of this problematic waste.

  4. Properties of sintered glass-ceramics prepared from plasma vitrified air pollution control residues

    Roether, J.A.; Daniel, D.J.; Amutha Rani, D.; Deegan, D.E.; Cheeseman, C.R.; Boccaccini, A.R.

    2010-01-01

    Air pollution control (APC) residues, obtained from a major UK energy from waste (EfW) plant, processing municipal solid waste, have been blended with silica and alumina and melted using DC plasma arc technology. The glass produced was crushed, milled, uni-axially pressed and sintered at temperatures between 750 and 1150 deg. C, and the glass-ceramics formed were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Mechanical properties assessed included Vickers's hardness, flexural strength, Young's modulus and thermal shock resistance. The optimum sintering temperature was found to be 950 deg. C. This produced a glass-ceramic with high density (∼2.58 g/cm 3 ), minimum water absorption (∼2%) and relatively high mechanical strength (∼81 ± 4 MPa). Thermal shock testing showed that 950 deg. C sintered samples could withstand a 700 deg. C quench in water without micro-cracking. The research demonstrates that glass-ceramics can be readily formed from DC plasma treated APC residues and that these have comparable properties to marble and porcelain. This novel approach represents a technically and commercially viable treatment option for APC residues that allow the beneficial reuse of this problematic waste.

  5. Preparation and characterisation of TeO.sub.2./sub. based glasses

    Pedlíková, Jitka; Zavadil, Jiří; Procházková, Olga; Kalužný, J.

    480-481, - (2005), s. 315-322 ISSN 0255-5476. [APHYS-2003 /1./. Badajoz, 03.10.13-03.10.18] R&D Projects: GA ČR(CZ) GA104/02/0799 Institutional research plan: CEZ:AV0Z2067918 Keywords : glass * fluorescence * transmission Subject RIV: CA - Inorganic Chemistry Impact factor: 0.399, year: 2005

  6. Novel selenium containing boro-phosphate glasses: preparation and structural study.

    Ciceo-Lucacel, R; Radu, T; Ponta, O; Simon, V

    2014-06-01

    We synthesized a new boro-phosphate glass system with different %mol SeO2 content by conventional melt quenching technique. All samples were obtained in a glassy state with the vitreous structure confirmed by X-ray diffraction analysis. Scanning electron microscopy (SEM) revealed some non-homogeneous domains on the glasses surface, and their tendency to link each other once the selenium oxide content increases. Energy-dispersive X-ray analysis (EDAX) indicated similar elemental composition in different regions of each sample. X-ray photoelectron spectroscopy (XPS) was used to determine the nature of chemical bonding and the elemental composition at the sample surfaces, and Fourier transform infrared (FT-IR) spectroscopy was used to determine the structural groups in the obtained glass structure. Based on FT-IR results, the glass structure at short range order consists mainly of small phosphate units such as pyrophosphate (i.e. P2O7(4-) dimmers or terminating groups at the end of phosphate chains) and some metaphosphate (i.e. PO3(-) middle groups in the phosphate chains) units. The boron atoms are mainly placed in three-coordinated sites in BØ3 or BØ2O(-) units. A small contribution of BØ4(-) units was also detected from the FT-IR spectra of glasses. For SeO2 content higher than 5mol%, the modifier role of selenium ions is strongly reflected on the local structure dominated in this case by pyrophosphate units. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. The borosilicate glass for 'PAMELA'

    Schiewer, E.

    1986-01-01

    The low enriched waste concentrate (LEWC) stored at Mol, Belgium, will be solidified in the vitrification plant 'PAMELA'. An alkali-borosilicate glass was developed by the Hahn-Meitner-Institut, Berlin, which dissolves (11 +- 3)wt% waste oxides while providing sufficient flexibility for changes in the process parameters. The development of the glass labelled SM513LW11 is described. Important properties of the glass melt (viscosity, resistivity, formation of yellow phase) and of the glass (corrosion in aqueous solutions, crystallization) are reported. The corrosion data of this glass are similar to those of other HLW-glasses. Less than five wt% of crystalline material are produced upon cooling of large glass blocks. Crystallization does not affect the chemical durability. (Auth.)

  8. Highly conductive cathode materials for Li-ion batteries prepared by thermal nanocrystallization of selected oxide glasses

    Pietrzak, T.K.; Wasiucionek, M.; Michalski, P.P.; Kaleta, A.; Garbarczyk, J.E., E-mail: garbar@if.pw.edu.pl

    2016-11-15

    Glassy analogs of two important cathode materials for Li-ion cells: V{sub 2}O{sub 5} and phosphoolivine LiFePO{sub 4} were heat-treated in order to prepare nanocrystallized materials with high electronic conductivity of up to 7 × 10{sup −2} S cm{sup −1} and ca 7 × 10{sup −3} S cm{sup −1} at 25 °C, respectively. There is a clear correlation between the crystallization phenomena and the increase in the electrical conductivity for both groups of glasses. Electrochemical tests of heat-treated glasses of the V{sub 2}O{sub 5}–P{sub 2}O{sub 5} system, used as cathodes in lithium cells confirm their good gravimetric capacity and reversibility. Heat-treatment of glasses of the Li{sub 2}O–FeO–V{sub 2}O{sub 5}–P{sub 2}O{sub 5} system also leads to a high increase in the conductivity and to formation of nanocrystalline grains in the glassy matrix, evidenced by HR-TEM images. The temperature dependence of the conductivity of these materials follows the Arrhenius formula. The presented results indicate that the overall increase in conductivity in nanocrystallized materials is due to good charge transport properties of their interfacial regions.

  9. Production of a High-Level Waste Glass from Hanford Waste Samples

    Crawford, C.L.; Farrara, D.M.; Ha, B.C.; Bibler, N.E.

    1998-09-01

    The HLW glass was produced from a HLW sludge slurry (Envelope D Waste), eluate waste streams containing high levels of Cs-137 and Tc-99, solids containing both Sr-90 and transuranics (TRU), and glass-forming chemicals. The eluates and Sr-90/TRU solids were obtained from ion-exchange and precipitation pretreatments, respectively, of other Hanford supernate samples (Envelopes A, B and C Waste). The glass was vitrified by mixing the different waste streams with glass-forming chemicals in platinum/gold crucibles and heating the mixture to 1150 degree C. Resulting glass analyses indicated that the HLW glass waste form composition was close to the target composition. The targeted waste loading of Envelope D sludge solids in the HLW glass was 30.7 wt percent, exclusive of Na and Si oxides. Condensate samples from the off-gas condenser and off-gas dry-ice trap indicated that very little of the radionuclides were volatilized during vitrification. Microstructure analysis of the HLW glass using Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Analysis (EDAX) showed what appeared to be iron spinel in the HLW glass. Further X-Ray Diffraction (XRD) analysis confirmed the presence of nickel spinel trevorite (NiFe2O4). These crystals did not degrade the leaching characteristics of the glass. The HLW glass waste form passed leach tests that included a standard 90 degree C Product Consistency Test (PCT) and a modified version of the United States Environmental Protection Agency Toxicity Characteristic Leaching Procedure (TCLP)

  10. Novel selenium containing boro-phosphate glasses: Preparation and structural study

    Ciceo-Lucacel, R.; Radu, T., E-mail: teodora.radu@phys.ubbcluj.ro; Ponta, O.; Simon, V.

    2014-06-01

    We synthesized a new boro-phosphate glass system with different %mol SeO{sub 2} content by conventional melt quenching technique. All samples were obtained in a glassy state with the vitreous structure confirmed by X-ray diffraction analysis. Scanning electron microscopy (SEM) revealed some non-homogeneous domains on the glasses surface, and their tendency to link each other once the selenium oxide content increases. Energy-dispersive X-ray analysis (EDAX) indicated similar elemental composition in different regions of each sample. X-ray photoelectron spectroscopy (XPS) was used to determine the nature of chemical bonding and the elemental composition at the sample surfaces, and Fourier transform infrared (FT-IR) spectroscopy was used to determine the structural groups in the obtained glass structure. Based on FT-IR results, the glass structure at short range order consists mainly of small phosphate units such as pyrophosphate (i.e. P{sub 2}O{sub 7}{sup 4−} dimmers or terminating groups at the end of phosphate chains) and some metaphosphate (i.e. PO{sub 3}{sup −} middle groups in the phosphate chains) units. The boron atoms are mainly placed in three-coordinated sites in BØ{sub 3} or BØ{sub 2}O{sup −} units. A small contribution of BØ{sub 4}{sup −} units was also detected from the FT-IR spectra of glasses. For SeO{sub 2} content higher than 5 mol%, the modifier role of selenium ions is strongly reflected on the local structure dominated in this case by pyrophosphate units. - Highlights: • New P{sub 2}O{sub 5}-CaO-B{sub 2}O{sub 3}-SeO{sub 2} glasses synthesized by conventional melt quenching method. • Evidences for the Se ions modifier role in the local structure by FT-IR and XPS. • Significant advances in understanding the structural properties of the new system.

  11. Preparation and characterization of nanocrystalline ITO thin films on glass and clay substrates by ion-beam sputter deposition method

    Venkatachalam, S.; Nanjo, H.; Kawasaki, K.; Wakui, Y.; Hayashi, H.; Ebina, T.

    2011-01-01

    Nanocrystalline indium tin oxide (ITO) thin films were prepared on clay-1 (Clay-TPP-LP-SA), clay-2 (Clay-TPP-SA) and glass substrates using ion-beam sputter deposition method. X-ray diffraction (XRD) patterns showed that the as-deposited ITO films on both clay-1 and clay-2 substrates were a mixture of amorphous and polycrystalline. But the as-deposited ITO films on glass substrates were polycrystalline. The surface morphologies of as-deposited ITO/glass has smooth surface; in contrast, ITO/clay-1 has rough surface. The surface roughnesses of ITO thin films on glass and clay-1 substrate were calculated as 4.3 and 83 nm, respectively. From the AFM and SEM analyses, the particle sizes of nanocrystalline ITO for a film thickness of 712 nm were calculated as 19.5 and 20 nm, respectively. Optical study showed that the optical transmittance of ITO/clay-2 was higher than that of ITO/clay-1. The sheet resistances of as-deposited ITO/clay-1 and ITO/clay-2 were calculated as 76.0 and 63.0 Ω/□, respectively. The figure of merit value for as-deposited ITO/clay-2 (12.70 x 10 -3 /Ω) was also higher than that of ITO/clay-1 (9.6 x 10 -3 /Ω), respectively. The flexibilities of ITO/clay-1 and ITO/clay-2 were evaluated as 13 and 12 mm, respectively. However, the ITO-coated clay-2 substrate showed much better optical and electrical properties as well as flexibility as compared to clay-1.

  12. SNF/HLW Transfer System Description Document

    W. Holt

    2005-01-01

    The purpose of this system description document (SDD) is to establish requirements that drive the design of the spent nuclear fuel (SNF)/high-level radioactive waste (HLW) transfer system and associated bases, which will allow the design effort to proceed to license application. This SDD will be revised at strategic points as the design matures. This SDD identifies the requirements and describes the system design, as it currently exists, with emphasis on attributes of the design provided to meet the requirements. This SDD is an engineering tool for design control. Accordingly, the primary audience and users are design engineers. This SDD is part of an iterative design process. It leads the design process with regard to the flowdown of upper tier requirements onto the system. Knowledge of these requirements is essential in performing the design process. The SDD follows the design with regard to the description of the system. The description provided in this SDD reflects the current results of the design process

  13. Stress analysis of HLW containers. Compas project

    1989-01-01

    This document reports the work carried out for the Compas project which looked at the performance of various computer codes in a selected benchmark exercise. This exercise consisted of several analyses on simplified models which have features typical of HLW containers. These analyses comprise two groups; one related to thick walled, stressed shell overpacks, the other related to thin walled, supported shell overpacks with a lead filler. The first set of analyses looked at an elastic-plastic behaviour and large deformation of a cylinder representative of the main body of thick walled containers). The second set looked at creep behaviour of the lead filler, and the shape the base of thin walled containers will take up, after hundreds of years in the repository. On the thick walled analyses with the cylinder subject to an external pressure all the codes gave consistent results in the elastic region and there is good agreement in the yield pressures. Once in the plastic region there is more divergence in the results although a consistent trend is predicted. One of the analyses predicted a non-axisymmetric mode of deformation as would be expected in reality. Fewer results were received for the creep analysis, however the transient creep results showed consistency, and were bounded by the final-state results

  14. Variation in Pockels constants of silicate glass-ceramics prepared by perfect surface crystallization

    Takano, Kazuya; Takahashi, Yoshihiro; Miyazaki, Takamichi; Terakado, Nobuaki; Fujiwara, Takumi

    2018-01-01

    We investigated the Pockels effect in polycrystalline materials consisting of highly oriented polar fresnoite-type Sr2TiSi2O8 fabricated using perfectly surface-crystallized glass-ceramics (PSC-GCs). The chemical composition of the precursor glass was shown to significantly affect the crystallized texture, e.g., the crystal orientation and appearance of amorphous nanoparasites in the domains, resulting in variations in the Pockels constants. Single crystals exhibiting spontaneous polarization possessed large structural anisotropy, leading to a strong dependence of the nonlinear-optical properties on the direction of polarized light. This study suggests that variations in the Pockels constants (r13 and r33) and tuning of the r13/r33 ratio can be realized in PSC-GC materials.

  15. Preparation and characterization of Zr-based bulk metallic glasses in form of plate

    Pilarczyk, Wirginia

    2014-01-01

    Highlights: • Zr-based BMGs in form of plate was successful produced by die pressure casting method. • Many techniques have been used to characterize the structure of Zr 55 Cu 30 Ni 5 Al 10 alloy. • The calculated GFA parameters show that the alloy exhibits satisfactory GFA. • The studies reveal that tested as-cast Zr-based alloy is in amorphous state. - Abstract: Zr-based bulk metallic glasses present an interesting combination of physical, chemical and mechanical properties. During the last decade, intensive progress has been made and a number of applications have been suggested for these materials. In order to successfully apply these materials, it is necessary to accurately characterize their structure, thermal stability and other properties accurately. The aim of the presented work is the manufacturing, examination of the structure of selected Zr-based bulk metallic alloys and confirmation of an amorphous structure using X-ray analysis, microscopic observation and thermal analysis. In this work, the Zr-based bulk metallic glasses in form of plate was successful produced by die pressure casting method. Designed scientific station for casting zirconium based amorphous alloys in the form of plates and rods with selected dimensions is in our university a comprehensive method for achieving amorphous materials which enables us to maintain repeatability of as-cast samples with the amorphous structure and the assumed dimensions range. The diffraction pattern and exothermic reaction as well as the fracture surface morphology reveal that studied as-cast Zr-based alloy is in amorphous state. The calculated GFA parameters show that the alloy exhibits satisfactory glass-forming ability in form of studied plate. These obtained values can suggest that studied alloys are suitable materials for further planned practical application at welding process. The success of Zr-based bulk metallic glasses production in form of plate with obtained sizes is important for future

  16. Structural study of thin films prepared from tungstate glass matrix by Raman and X-ray absorption spectroscopy

    Montanari, Bianca; Barbosa, Anne J.; Ribeiro, Sidney J.L.; Messaddeq, Younes [Departamento de Quimica Geral e Inorganica, Instituto de Quimica, UNESP, CP 355, CEP 14800-900 Araraquara, SP (Brazil); Poirier, Gael [Departamento de Ciencias Exatas, UNIFAL-MG, CEP 37130-000 Alfenas, MG (Brazil)], E-mail: gael@unifal-mg.edu.br; Li, Maximo S. [Instituto de Fisica, USP, CP 369, CEP 13560-970 Sao Carlos, SP (Brazil)

    2008-06-30

    Thin films were prepared using glass precursors obtained in the ternary system NaPO{sub 3}-BaF{sub 2}-WO{sub 3} and the binary system NaPO{sub 3}-WO{sub 3} with high concentrations of WO{sub 3} (above 40% molar). Vitreous samples have been used as a target to prepare thin films. Such films were deposited using the electron beam evaporation method onto soda-lime glass substrates. Several structural characterizations were performed by Raman spectroscopy and X-ray Absorption Near Edge Spectroscopy (XANES) at the tungsten L{sub I} and L{sub III} absorption edges. XANES investigations showed that tungsten atoms are only sixfold coordinated (octahedral WO{sub 6}) and that these films are free of tungstate tetrahedral units (WO{sub 4}). In addition, Raman spectroscopy allowed identifying a break in the linear phosphate chains as the amount of WO{sub 3} increases and the formation of P-O-W bonds in the films network indicating the intermediary behavior of WO{sub 6} octahedra in the film network. Based on XANES data, we suggested a new attribution of several Raman absorption bands which allowed identifying the presence of W-O{sup -} and W=O terminal bonds and a progressive apparition of W-O-W bridging bonds for the most WO{sub 3} concentrated samples (above 40% molar) attributed to the formation of WO{sub 6} clusters.

  17. Structural studies on iron-tellurite glasses prepared by sol-gel method

    Rada, S., E-mail: Simona.Rada@phys.utcluj.r [Department of Physics, Technical University of Cluj-Napoca, Bibliotecii, No. 10, 400020 Cluj-Napoca (Romania); Dehelean, A. [Department of Physics, Technical University of Cluj-Napoca, Bibliotecii, No. 10, 400020 Cluj-Napoca (Romania); Nat. Inst. for R and D of Isotopic and Molec. Technologies, Cluj-Napoca (Romania); Stan, M. [Nat. Inst. for R and D of Isotopic and Molec. Technologies, Cluj-Napoca (Romania); Chelcea, R. [Department of Physics, Technical University of Cluj-Napoca, Bibliotecii, No. 10, 400020 Cluj-Napoca (Romania); Nat. Inst. for R and D of Isotopic and Molec. Technologies, Cluj-Napoca (Romania); Culea, E. [Department of Physics, Technical University of Cluj-Napoca, Bibliotecii, No. 10, 400020 Cluj-Napoca (Romania)

    2011-01-05

    Research highlights: {yields} Iron-tellurite glasses obtained using the sol-gel synthesis. - Abstract: In this study, we report structural properties of the iron-tellurite glasses obtained using the sol-gel synthesis. The samples were characterized by X-ray diffraction, FTIR, UV-vis and EPR spectroscopy. Our results indicate dominant presence of iron ions in the trivalent state and the existence some Fe{sup 2+} ions. The analysis of the IR spectra indicates a gradual transformation of iron ions from tetrahedral into octahedral sites when the concentration of Fe(NO{sub 3}){sub 3} is increased beyond 0.64 mol%. EPR studies show that the increase of Fe(NO{sub 3}){sub 3} content in the host matrix induces the growth of the number of effective g values. This can be explained considering that the orbitals of O{sup 2-} ion with a large spin-orbit interaction constant will interact with the 3d orbital of Fe{sup 3+} ion bonded to this O{sup 2-} ion, thus leading to appearance of an orbital angular momentum which contributes to the magnetic moment of Fe{sup 3+} ion. A strong dipolar interaction, which is more predominant in a glass with higher content of Fe(NO{sub 3}){sub 3}, causing a localized magnetic field along the site of the Fe{sup 3+} ions and the increase the effective g values.

  18. Preparation of special purity Ge - S - I and Ge - Se - I glasses

    Velmuzhov, A. P.; Sukhanov, M. V.; Shiryaev, V. S.; Kotereva, T. V.; Snopatin, G. E.; Churbanov, M. F.

    2017-05-01

    The paper considers the new approaches for the production of special pure Ge - S - I and Ge - Se - I glasses via the germanium(IV) iodide, germanium(II) sulfide, as well as the Ge2S3, Ge2S3I2 and Ge2Se3I2 glassy alloys. The glass samples containing 0.03-0.17 ppm(wt) hydrogen impurity in the form of SH-group, 0.04-0.15 ppm(wt) hydrogen impurity in the form of SeH-group, and 0.5-7.8 ppm(wt) oxygen impurity in the form of Ge-O were produced. Using a crucible technique, the single-index [GeSe4]95I5 glass fibers of 300-400 μm diameter were drawn. The minimum optical losses in the best fiber were 1.7 dB/m at a wavelength of 5.5 μm; the background optical losses were within 2-3 dB/m in the spectral range of 2.5-8 μm.

  19. Preparation and properties of Nd{sup 3+}:SrAlF{sub 5} nanocrystals embedded fluorophosphate transparent glass-ceramic with long fluorescence lifetime

    Zheng, Ruilin; Wang, Jinlong; Zhang, Liaolin; Liu, Chunxiao; Wei, Wei [Nanjing University of Posts and Telecommunications, School of Optoelectronic Engineering, Nanjing (China)

    2016-07-15

    Nd{sup 3+}:SrAlF{sub 5} nanocrystals embedded fluorophosphate glass-ceramics were prepared by the melt quenching and subsequent thermal treatment method. The formation of SrAlF{sub 5} nanocrystals in the glass was confirmed by X-ray diffraction and scanning electron microscope. The fluorescence intensity and lifetime of the glass-ceramics increased with the increase of size of nanocrystals. Importantly, by controlling growth of nanocrystals, an obvious enhancement of lifetime (725 μs) emerged in the glass-ceramics heat-treated at 510 C and the transmittance can reach to 72.2 % at 1049 nm. The enhanced fluorescence intensity and lifetime were ascribed to the comfortable local environment to the Nd{sup 3+} ion and scattering of the nanoparticle embedded into the glass matrix. (orig.)

  20. Characterization of iron phosphate glasses prepared by microwave heating; Obtencao de vidros fosfatos contendo ferro por meio do aquecimento em fornos de microondas

    Almeida, Fabio Jesus Moreira de

    2006-07-01

    Phosphate glasses have been investigated since the fifties, because they are relatively easy to prepare, have low melting temperatures (1000 deg C - 1200 deg C), and low glass transition. However, these glasses were very sensitive to humidity, showing a very low chemical durability. Iron phosphate glasses have been prepared by melting inorganic precursors in conventional electric furnaces and induction furnaces. By adding iron, phosphate glasses became chemical resistant and were thought to be used as nuclear waste forms or mechanical resistance fibers. The use of microwaves has been investigated because it makes possible a fast and homogeneous heating of the materials. Microwave promotes the self-heating of the material by the interaction of the external electromagnetic field with the molecules and ions of the material. Niobium phosphate glasses was also produced already through the heating of precursors in microwave ovens. Other glasses containing iron in theirs structure was produced by conventional furnaces and they had your structures analyzed. But even so, it was not still published synthesis of iron phosphate glasses starting from the melting of precursors materials in microwave ovens. In the present work mixtures of (NH{sub 4}){sub 2}HPO{sub 4} and Fe{sub 3}O{sub 4} or (NH{sub 4}){sub 2}HPO{sub 4} and Fe{sub 2}O{sub 3} were exposed to microwave energy with electromagnetic waves of 2,45 GHz. It was proposed that the absorption of this radiation for the material causes the heating from room temperature to melting temperature. The obtained iron phosphate glasses was analyzed by X-ray diffraction, Moessbauer spectroscopy, and Differential Thermal Analysis. Iron phosphate glasses were also produced in electrical furnaces for comparison. (author)

  1. Preparation of Nanofibrous Structure of Mesoporous Bioactive Glass Microbeads for Biomedical Applications

    Shiao-Wen Tsai

    2016-06-01

    Full Text Available A highly ordered, mesoporous (pore size 2~50 nm bioactive glass (MBG structure has a greater surface area and pore volume and excellent bone-forming bioactivity compared with traditional bioactive glasses (BGs. Hence, MBGs have been used in drug delivery and bone tissue engineering. MBGs can be developed as either a dense or porous block. Compared with a block, microbeads provide greater flexibility for filling different-shaped cavities and are suitable for culturing cells in vitro. In contrast, the fibrous structure of a scaffold has been shown to increase cell attachment and differentiation due to its ability to mimic the three-dimensional structure of natural extracellular matrices. Hence, the aim of this study is to fabricate MBG microbeads with a fibrous structure. First, a sol-gel/electrospinning technique was utilized to fabricate the MBG nanofiber (MBGNF structure. Subsequently, the MBGNF microbeads (MFBs were produced by an electrospraying technology. The results show that the diameter of the MFBs decreases when the applied voltage increases. The drug loading and release profiles and mechanisms of the MFBs were also evaluated. MFBs had a better drug entrapment efficiency, could reduce the burst release of tetracycline, and sustain the release over 10 days. Hence, the MFBs may be suitable drug carriers. In addition, the cellular attachment of MG63 osteoblast-like cells is significantly higher for MFBs than for glass microbeads after culturing for 4 h. The nanofibrous structure of MFBs could provide an appropriate environment for cellular spreading. Therefore, MFBs have great potential for use as a bone graft material in bone tissue engineering applications.

  2. Preparation and characterization of Zr-based bulk metallic glasses in form of plate

    Pilarczyk, Wirginia, E-mail: wirginia.pilarczyk@polsl.pl

    2014-12-05

    Highlights: • Zr-based BMGs in form of plate was successful produced by die pressure casting method. • Many techniques have been used to characterize the structure of Zr{sub 55}Cu{sub 30}Ni{sub 5}Al{sub 10} alloy. • The calculated GFA parameters show that the alloy exhibits satisfactory GFA. • The studies reveal that tested as-cast Zr-based alloy is in amorphous state. - Abstract: Zr-based bulk metallic glasses present an interesting combination of physical, chemical and mechanical properties. During the last decade, intensive progress has been made and a number of applications have been suggested for these materials. In order to successfully apply these materials, it is necessary to accurately characterize their structure, thermal stability and other properties accurately. The aim of the presented work is the manufacturing, examination of the structure of selected Zr-based bulk metallic alloys and confirmation of an amorphous structure using X-ray analysis, microscopic observation and thermal analysis. In this work, the Zr-based bulk metallic glasses in form of plate was successful produced by die pressure casting method. Designed scientific station for casting zirconium based amorphous alloys in the form of plates and rods with selected dimensions is in our university a comprehensive method for achieving amorphous materials which enables us to maintain repeatability of as-cast samples with the amorphous structure and the assumed dimensions range. The diffraction pattern and exothermic reaction as well as the fracture surface morphology reveal that studied as-cast Zr-based alloy is in amorphous state. The calculated GFA parameters show that the alloy exhibits satisfactory glass-forming ability in form of studied plate. These obtained values can suggest that studied alloys are suitable materials for further planned practical application at welding process. The success of Zr-based bulk metallic glasses production in form of plate with obtained sizes is

  3. Preparation of high-purity Pr{sup 3+} doped Ge–As–Se–In–I glasses for active mid-infrared optics

    Karaksina, E.V.; Shiryaev, V.S., E-mail: shiryaev@ihps.nnov.ru; Kotereva, T.V.; Velmuzhov, A.P.; Ketkova, L.A.; Snopatin, G.E.

    2016-09-15

    The multi-stage method for the synthesis of high-purity Ge–As–Se–In–I glasses doped with Pr{sup 3+} ions is developed. It is based on the chemical distillation purification of glass-forming melt and the chemical transport reactions for purification and vacuum loading of indium. The level of purity of glasses, synthesized by this method, is higher in comparison with the traditional direct melting method for glass synthesis. The high-purity Pr{sup 3+}-doped Ge–As–Se–In and Pr{sup 3+}-doped Ge–As–Se–In–I glass samples are prepared; the optical, thermal and luminescent properties are investigated. The purest host glass samples, obtained by the multi-stage purification techniques, contain a low concentration of limiting impurities: hydrogen − ≤0.05 ppm (wt) and oxygen − ≤0.1 ppm (wt), that is, at present, the best result for multi-component chalcogenide glasses for mid-IR active fibers. The samples of Pr{sup 3+}-doped Ge–As–Se–In glass fibers have the minimum optical losses of 0.58 dB/m at the wavelength of 2.72 μm and exhibit an intense broadband luminescence in the spectral range of 3.5–5.5 μm, with a maximum shifted to longer wavelengths as compared with the bulk samples.

  4. HLW Flexible jumper materials compatibility evaluation

    Skidmore, T. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-11-13

    H-Tank Farm Engineering tasked SRNL/Materials Science & Technology (MS&T) to evaluate the compatibility of Goodyear Viper® chemical transfer hose with HLW solutions. The hose is proposed as a flexible Safety Class jumper for up to six months service. SRNL/MS&T performed various tests to evaluate the effects of radiation, high pH chemistry and elevated temperature on the hose, particularly the inner liner. Test results suggest an upper dose limit of 50 Mrad for the hose. Room temperature burst pressure values at 50 Mrad are estimated at 600- 800 psi, providing a safety factor of 4.0-5.3X over the anticipated operating pressure of 150 psi and a safety factor of 3.0-4.0X over the working pressure of the hose (200 psi), independent of temperature effects. Radiation effects are minimal at doses less than 10 Mrad. Doses greater than 50 Mrad may be allowed, depending on operating conditions and required safety factors, but cannot be recommended at this time. At 250 Mrad, burst pressure values are reduced to the hose working pressure. At 300 Mrad, burst pressures are below 150 psi. At a bounding continuous dose rate of 57,870 rad/hr, the 50 Mrad dose limit is reached within 1.2 months. Actual dose rates may be lower, particularly during non-transfer periods. Refined dose calculations are therefore recommended to justify longer service. This report details the tests performed and interpretation of the results. Recommendations for shelf-life/storage, component quality verification, and post-service examination are provided.

  5. The preparation of dental glass-ceramic composites with controlled fraction of leucite crystals

    Martina Mrázová

    2008-06-01

    Full Text Available This work is dealing with synthesis of leucite powder, which can be used for the preparation of dental glassceramic composites by subsequent thermal treatment. Newly developed procedure is based on preparation of dental raw material as a mixture of two separate compounds: the crystalline leucite powder prepared at relatively low temperature and a commercial matrix powder.Hydrothermal synthesis of tetragonal leucite particles (KAlSi2O6 with the average size of about 3 μm was developed in our laboratory. The leucite dental raw material was prepared by mixing of 20 wt.% of synthetic tetragonal leucite with commercial matrix. Dental composites were prepared from the dental raw material by uniaxial pressing and firing up to 960°C. Dilatometric measurements confirmed that the coefficient of thermal expansion increased by 32% when 20 wt.% of the tetragonal leucite was added into the basic matrix. In addition, it was showed that the synthesized leucite powder was suitable for the preparation of leucite composites with controlled coefficient of thermal expansion. High value of the thermal expansion coefficient enables application of prepared composite in metal-ceramics restorations.

  6. Characterization of borosilicate glasses containing simulated high-level radioactive wastes from PNC

    Terai, R.; Eguchi, K.; Yamanaka, H.

    1979-01-01

    The characterization of borosilicate glasses containing simulated HLW from PNC has been carried out. Phase separation of molybdates, volatilization, viscosity, electrical resistivity, thermal conductivity, elastic modulus, chemical durability, and devitrification of these glasses have been measured, and the suitability of the glasses for the vitrified solidification processes is discussed from the viewpoint of safety

  7. Preparation of concrete mixtures with electric arc furnace slag and recycled ground glass

    Pérez Rojas, Y.; López, E. Vera; López Rodríguez, M.; Díaz Pita, J.

    2017-12-01

    The present work includes the first advances in the development of investigations that seek to include Ground Grinding Glass (GRR) and the Electric Arc Furnace Slag (EAFS) in the production of mixtures of hydraulic concrete mixing them simultaneously, so that it satisfies the specifications techniques to be used in the construction of rigid pavements. Firstly, we cite the tests carried out on the different materials to obtain their physical, chemical and mechanical characterization and determine their compliance, as well as the measurement of certain characteristics that may be somewhat empirical to standardize their control. Technique such as X-Ray Diffraction (XRD), X-ray Fluorescence Spectrometry (XFR) and Scanning Electron Microscopy (SEM) have been used. Once the results of the characterization tests and their correspondence with the Colombian technical standards have been obtained, it has become possible to select the use of the Transparent Recycled Ground Glass (TRGG) as the most suitable for the replacement of the sand in the dosage of new mixtures modified concrete.

  8. Crystallization kinetics of magnetic glass-ceramics prepared by the processing of waste materials

    Francis, A.A.

    2006-01-01

    The objective of the present investigation was to study the feasibility of conversion of an intimate mixture of blast furnace slag and blast furnace flue dust generated by a single industrial company into magnetic glass-ceramic product. Blast furnace slag (BFS) and blast furnace flue dust (BFD) are generated at a rate of 300,000 and 30,000 tons/year, respectively, from iron and steel factory. The crystallization mechanisms of a composition containing BFS and BFD in a 50/50 proportion were investigated by differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The crystallization temperature was found to vary from 900 to 1100 deg. C and two phases appeared in the crystallized samples: pyroxene Ca(Mg, Fe, Al)(Si, Al) 2 O 6 and magnetite/maghemite. Heating rate and particle sizes effects on crystal growth of powdered samples were studied by DTA. The apparent activation energy of crystal growth using the particle size 180-315 μm was determined to be 355 and 329 kJ/mol for the first and second peak, respectively. The presence of sharp and broad crystallization peaks indicate simultaneous surface and internal crystallization mechanism. Good wear resistance and chemical durability particularly in alkaline environment, combine with good hardness and magnetic properties make this glass-ceramic material potentially useful for various industrial applications

  9. Technology for the long-term management of defense HLW at the Idaho Chemical Processing Plant

    Staples, B.A.; Berreth, J.R.; Knecht, D.A.

    1986-01-01

    The Defense Waste Management Plan of June 1983 includes a reference plan for the long-term management of Idaho Chemical Processing Plant (ICPP) high-level waste (HLW), with a goal of disposing of the annual output in 500 canisters a year by FY-2008. Based on the current vitrification technology, the ICPP base-glass case would produce 1700 canisters per year after FY-2007. Thus, to meet the DWMP goal processing steps including fuel dissolution, waste treatment, and waste immobilization are being studied as areas where potential modifications could result in HLW volume reductions for repository disposal. It has been demonstrated that ICPP calcined wastes can be densified by hot isostatic pressing to multiphase ceramic forms of high loading and density. Conversion of waste by hot isostatic pressing to these forms has the potential of reducing the annual ICPP waste production to volumes near those of the goal of the DWMP. This report summarizes the laboratory-scale information currently available on the development of these forms

  10. An Efficient Covalent Coating on Glass Slides for Preparation of Optical Oligonucleotide Microarrays

    Atefeh Pourjahed

    2013-12-01

    The agarose-PLL microarrays had the highest signal (2546 and lowest background signal (205 in hybridization, suggesting that the prepared slides are suitable in analyzing wide concentration range of analytes.

  11. Preparation and characterization of very pure zirconium tetrafluoride. Application to fluorinated glass

    Bridenne, M.

    1986-12-01

    The synthesis of anhydrous and very pure zirconium tetrafluoride from zirconium tetraborohydride is studied. Zr F 4 is used for fabrication of fluorozirconate glass. Zr (BH 4 ) 4 is purified by sublimation. Two fluorinating agents F 2 and anhydrous HF are used for fluorination. The apparatus is made of fluorinated polymers and a Kel-F prototype reactor was realized. 20 g of Zr F 4 are obtained in 44 hrs with a yield of 88 %. Purity is characterized by chemical analysis (atomique absorption spectroscopy and spark mass spectroscopy) and absorption of an optical fiber made of zirconium tetrafluoride. Cr, Ni, Co and Cu content is lower than 0.1 ppm. Possibility of pilot scale production is discussed [fr

  12. The antimicrobial activity of as-prepared silver-loaded phosphate glasses and zirconium phosphate

    Jing, Wang; Jiang, Ji Zhi; Yang, Yang; Yan, Zhao Chun; Yan, Wang Xiao; He, Shui Zhong

    2016-01-01

    The antimicrobial activities of silver-loaded zirconium phosphate (JDG) and silver-loaded phosphate glasses (ZZB) against Escherichia coli were studied. Although the silver content in JDG was higher than that in ZZB, ZZB suspensions showed better antimicrobial property than JDG suspensions, especially at low concentrations. The antimicrobial activity was analyzed using minimum inhibitory concentrations, bacterial inhibition ring tests, and detection of silver ions in the suspensions. Furthermore, the amounts of silver ions in suspensions with/without bacterial cells were analyzed. Results revealed that only a portion of released silver ions could be adsorbed by E. coli cells, which are critical to cell death. The damaged microstructures of E. coli cells observed by transmission electron microscopy may further prove that the adsorbed silver ions play an important role in the antimicrobial process.

  13. Luminescence of Eu(3+) doped SiO2 Thin Films and Glass Prepared by Sol-gel Technology

    Castro, Lymari; Jia, Weiyi; Wang, Yanyun; Santiago, Miguel; Liu, Huimin

    1998-01-01

    Trivalent europium ions are an important luminophore for lighting and display. The emission of (5)D0 to (7)F2 transition exhibits a red color at about 610 nm, which is very attractive and fulfills the requirement for most red-emitting phosphors including lamp and cathode ray phosphorescence materials. Various EU(3+) doped phosphors have been developed, and luminescence properties have been extensively studied. On the other hand, sol-gel technology has been well developed by chemists. In recent years, applications of this technology to optical materials have drawn a great attention. Sol-gel technology provides a unique way to obtain homogeneous composition distribution and uniform doping, and the processing temperature can be very low. In this work, EU(3+) doped SiO2 thin films and glasses were prepared by sol-gel technology and their spectroscopic properties were investigated.

  14. R and D on HLW Partitioning in Russia

    Khaperskaya, A.; Babain, V.; Alyapyshev, M.

    2015-01-01

    Results of more than thirty years investigations on high level radioactive waste (HLW) partitioning in Russia are described. The objectives of research and development is to assess HLW partitioning technical feasibility and its advantages compared to direct vitrification of long-lived radionuclides. Many technological flowsheets for long-lived nuclides (cesium, strontium and minor actinides) separation were developed and tested with simulated and actual HLW. Different classes of extractants, including carbamoyl-phosphine oxides, dialkyl-phosphoric acids, crown ethers and diamides of heterocyclic acids were studied. Some of these processes were tested at PA 'Mayak' and MCC. Many extraction systems based on chlorinated cobalt dicarbollide (CCD), including UNEX-extractant and its modifications, were also observed. Diamides of diglycolic acid and diamides of heterocyclic acids in polar diluents have shown promising properties for minor actinide-lanthanide extraction and separation. Comparison of different solvents and possible ways of implementing new flowsheets in radiochemical technology are also discussed. (authors)

  15. HLW Canister and Can-In-Canister Drop Calculation

    H. Marr

    1999-01-01

    The purpose of this calculation is to evaluate the structural response of the standard high-level waste (HLW) canister and the HLW canister containing the cans of immobilized plutonium (''can-in-canister'' throughout this document) to the drop event during the handling operation. The objective of the calculation is to provide the structure parameter information to support the canister design and the waste handling facility design. Finite element solution is performed using the commercially available ANSYS Version (V) 5.4 finite element code. Two-dimensional (2-D) axisymmetric and three-dimensional (3-D) finite element representations for the standard HLW canister and the can-in-canister are developed and analyzed using the dynamic solver

  16. Final Report Start-Up And Commissioning Tests On The Duramelter 1200 HLW Pilot Melter System Using AZ-101 HLW Simulants VSL-01R0100-2, Rev. 0, 1/20/03

    Kruger, A.A.; Matlack, K.S.; Kot, W.K.; Brandys, M.; Wilson, C.N.; Schatz, T.R.; Gong, W.; Pegg, I.L.

    2011-01-01

    This document provides the final report on data and results obtained from commissioning tests performed on the one-third scale DuraMelter(trademark) 1200 (DM 1200) HLW Pilot Melter system that has been installed at VSL with an integrated prototypical off-gas treatment system. That system has replaced the DM1000 system that was used for HLW throughput testing during Part BI (1). Both melters have similar melt surface areas (1.2 m 2 ) but the DM1200 is prototypical of the present RPP-WTP HLW melter design whereas the DM1000 was not. These tests were performed under a corresponding RPP-WTP Test Specification and associated Test Plan. This report is a followup to the previously issued Preliminary Data Summary Report. The DM1200 system will be used for testing and confirmation of basic design, operability, flow sheet, and process control assumptions as well as for support of waste form qualification and permitting. This will include data on processing rates, off-gas treatment system performance, recycle stream compositions, as well as process operability and reliability. Consequently, this system is a key component of the overall HLW vitrification development strategy. The results presented in this report are from the initial series of short-duration tests that were conducted to support the start-up and commissioning of this system prior to conducting the main body of development tests that have been planned for this system. These tests were directed primarily at system 'debugging,' operator training, and procedure refinement. The AZ-101 waste simulant and glass composition that was used for previous testing was selected for these tests.

  17. FINAL REPORT START-UP AND COMMISSIONING TESTS ON THE DURAMELTER 1200 HLW PILOT MELTER SYSTEM USING AZ-101 HLW SIMULANTS VSL-01R0100-2 REV 0 1/20/03

    KRUGER AA; MATLACK KS; KOT WK; BRANDYS M; WILSON CN; SCHATZ TR; GONG W; PEGG IL

    2011-12-29

    This document provides the final report on data and results obtained from commissioning tests performed on the one-third scale DuraMelter{trademark} 1200 (DM 1200) HLW Pilot Melter system that has been installed at VSL with an integrated prototypical off-gas treatment system. That system has replaced the DM1000 system that was used for HLW throughput testing during Part BI [1]. Both melters have similar melt surface areas (1.2 m{sup 2}) but the DM1200 is prototypical of the present RPP-WTP HLW melter design whereas the DM1000 was not. These tests were performed under a corresponding RPP-WTP Test Specification and associated Test Plan. This report is a followup to the previously issued Preliminary Data Summary Report. The DM1200 system will be used for testing and confirmation of basic design, operability, flow sheet, and process control assumptions as well as for support of waste form qualification and permitting. This will include data on processing rates, off-gas treatment system performance, recycle stream compositions, as well as process operability and reliability. Consequently, this system is a key component of the overall HLW vitrification development strategy. The results presented in this report are from the initial series of short-duration tests that were conducted to support the start-up and commissioning of this system prior to conducting the main body of development tests that have been planned for this system. These tests were directed primarily at system 'debugging,' operator training, and procedure refinement. The AZ-101 waste simulant and glass composition that was used for previous testing was selected for these tests.

  18. Preparation and investigation of Pr{sup 3+}-doped Ge–Sb–Se–In–I glasses as promising material for active mid-infrared optics

    Shiryaev, V.S., E-mail: shiryaev@ihps.nnov.ru [G.G. Devyatykh Institute of Chemistry of High-Purity Substances of the Russian Academy of Sciences, 49 Tropinin Str., Nizhny Novgorod 603950 (Russian Federation); Karaksina, E.V.; Kotereva, T.V.; Churbanov, M.F.; Velmuzhov, A.P.; Sukhanov, M.V.; Ketkova, L.A.; Zernova, N.S. [G.G. Devyatykh Institute of Chemistry of High-Purity Substances of the Russian Academy of Sciences, 49 Tropinin Str., Nizhny Novgorod 603950 (Russian Federation); Plotnichenko, V.G.; Koltashev, V.V. [Fiber Optics Research Center of the Russian Academy of Sciences, 38 Vavilov Str., 119333 Moscow (Russian Federation)

    2017-03-15

    For the first time, high purity Ge–Sb–Se–In–I glasses doped with Pr{sup 3+} ions are prepared. The host Ge–Sb–Se–In-I glass samples are fabricated using a combination of chemical and distillation methods of purification as well as a chemical transport reaction route. The glass structure, the content of gas-forming impurities and particles, as well as the optical, thermal and luminescent properties were investigated. The host and Pr{sup 3+}-doped Ge–Sb–Se–In–I glasses are characterized by low optical losses in the mid-IR, low impurity content and high stability against crystallization. The content of hydrogen and oxygen impurities in the purest host glass samples, obtained using the multistep purification procedure, does not exceed 0.1 and 0.5 ppm(wt), respectively. The prepared Pr{sup 3+}-doped Ge–Sb–Se–In–I glasses exhibit intense broadband luminescence in the 3.5–6 μm spectral range, with a lifetime of 6 ms at the wavelength of 4.7 μm.

  19. Vitrification of HLW in cold crucible melter

    Bordier, G.

    2005-01-01

    The performance of the vitrification process currently used in the La Hague commercial reprocessing plants has been continuously improved during more than ten years of operation. In parallel the CEA (French Atomic Energy Commission), COGEMA (Industrial Operator), and SGN (COGEMA's Engineering) have developed the cold crucible melter vitrification technology to obtain greater operating flexibility, increased plant availability and further reduction of secondary waste generated during operations. The cold crucible is a compact water-cooled melter in which the radioactive waste and the glass additives are melted by direct high frequency induction. The cooling of the melter produces a solidified glass layer that protects the melter's inner wall from corrosion. Because the heat is transferred directly to the melt, high operating temperatures can be achieved with no impact on the melter itself. COGEMA plans to implement the cold crucible technology to vitrify high level liquid waste from reprocessed spent U-Mo-Sn-Al fuel (used in gas cooled reactor). The cold crucible was selected for the vitrification of this particularly hard-to-process waste stream because it could not be reasonably processed in the standard hot induction melters currently used at the La Hague vitrification facilities: the waste has a high molybdenum content which makes it very corrosive and also requires a special high temperature glass formulation to obtain sufficiently high waste loading factors (12 % in molybdenum). A special glass formulation has been developed by the CEA and has been qualified through lab and pilot testing to meet standard waste acceptance criteria for final disposal of the U-Mo waste. The process and the associated technologies have been also qualified on a full-scale prototype at the CEA pilot facility in Marcoule. Engineering study has been integrated in parallel in order to take into account that the Cold Crucible should be installed remotely in one of the R7 vitrification

  20. Interference of different ionic species on the analysis of phosphate in HLW using spectrophotometer

    Mishra, P.K.; Ghongane, D.E.; Valsala, T.P.; Sonavane, M.S.; Kulkarni, Y.; Changrani, R.D.

    2010-01-01

    During reprocessing of spent nuclear fuel by PUREX process different categories of radioactive liquid wastes like High Level (HL), Intermediate Level (IL) and Low Level (LL) are generated. Different methodologies are adopted for management of these wastes. Since PUREX solvent (30% Tri butyl phosphate-70% Normal Paraffin Hydrocarbon) undergoes chemical degradation in the highly acidic medium of dissolver solution, presence of phosphate in the waste streams is inevitable. Since higher concentrations of phosphate in the HLW streams will affect its management by vitrification, knowledge about the concentration of phosphate in the waste is essential before finalising the glass composition. Since a large number of anionic and cationic species are present in the waste, these species may interfere phosphate analysis using spectrophotometer. In the present work, the interference of different anionic and cationic species on the analysis of phosphate in waste solutions using spectrophotometer was studied

  1. Long-term storage or disposal of HLW-dilemma

    Ninkovic, M. M.; Raicevic, J.

    1995-01-01

    In this paper, a new concept approach to HLW management founded on deterministic safety philosophy - i.e. long-term storage with final objective of destroying was justified and proposed instead of multi barrier concept with final disposal in extra stable environmental conditions, which are founded on probabilistic safety approach model. As a support to this new concept some methods for destruction of waste which are now accessible, on scientific stage only, as transmutation in fast reactors and accelerators of heavy ions were briefly discussed . It is justified to believe that industrial technology for destruction of HLW would be developed in not so far future. (author).

  2. Active geothermal systems as natural analogs of HLW repositories

    Elders, W.A.; Williams, A.E.; Cohen, L.H.

    1988-01-01

    Geologic analogs of long-lived processes in high-level waste (HLW) repositories have been much studied in recent years. However, most of these occurrences either involve natural processes going on today at 25 degree C, or, if they are concerned with behavior at temperatures similar to the peak temperatures anticipated near HLW canisters, have long since ended. This paper points out the usefulness of studying modern geothermal systems as natural analogs, and to illustrate the concept with a dramatic example, the Salton Sea geothermal system (SSGS)

  3. Enhanced sludge processing of HLW: Hydrothermal oxidation of chromium, technetium, and complexants by nitrate. 1997 mid-year progress report

    Buelow, S.

    1997-01-01

    'Treatment of High Level Waste (HLW) is the second most costly problem identified by OEM. In order to minimize costs of disposal, the volume of HLW requiring vitrification and long term storage must be reduced. Methods for efficient separation of chromium from waste sludges, such as the Hanford Tank Wastes (HTW), are key to achieving this goal since the allowed level of chromium in high level glass controls waste loading. At concentrations above 0.5 to 1.0 wt.% chromium prevents proper vitrification of the waste. Chromium in sludges most likely exists as extremely insoluble oxides and minerals, with chromium in the plus III oxidation state [1]. In order to solubilize and separate it from other sludge components, Cr(III) must be oxidized to the more soluble Cr(VI) state. Efficient separation of chromium from HLW could produce an estimated savings of $3.4B[2]. Additionally, the efficient separation of technetium [3], TRU, and other metals may require the reformulation of solids to free trapped species as well as the destruction of organic complexants. New chemical processes are needed to separate chromium and other metals from tank wastes. Ideally they should not utilize additional reagents which would increase waste volume or require subsequent removal. The goal of this project is to apply hydrothermal processing for enhanced chromium separation from HLW sludges. Initially, the authors seek to develop a fundamental understanding of chromium speciation, oxidation/reduction and dissolution kinetics, reaction mechanisms, and transport properties under hydrothermal conditions in both simple and complex salt solutions. The authors also wish to evaluate the potential of hydrothermal processing for enhanced separations of technetium and TRU by examining technetium and TRU speciation at hydrothermal conditions optimal for chromium dissolution.'

  4. Preparation and characterization of glass fibers – polymers (epoxy bars (GFRP reinforced concrete for structural applications

    Alkjk Saeed

    2016-06-01

    Full Text Available The paper presents some of the results from a large experimental program undertaken at the Department of Civil Engineering of Damascus University. The project aims to study the ability to reinforce and strengthen the concrete by bars from Epoxy polymer reinforced with glass fibers (GFRP and compared with reinforce concrete by steel bars in terms of mechanical properties. Five diameters of GFRP bars, and steel bars (4mm, 6mm, 8mm, 10mm, 12mm tested on tensile strength tests. The test shown that GFRP bars need tensile strength more than steel bars. The concrete beams measuring (15cm wide × 15cm deep × and 70cm long reinforced by GFRP with 0.5 vol.% ratio, then the concrete beams reinforced by steel with 0.89 vol.% ratio. The concrete beams tested on deflection test. The test shown that beams which reinforced by GFRP has higher deflection resistance, than beams which reinforced by steel. Which give more advantage to reinforced concrete by GFRP.

  5. Development of a glass matrix for vitrification of sulphate bearing high level radioactive liquid waste

    Kaushik, C.P.; Mishra, R.K.; Thorat, Vidya; Ramchandran, M.; Amar Kumar; Ozarde, P.D.; Raj, Kanwar; Das, D.

    2004-07-01

    High level radioactive liquid waste (HLW) is generated during reprocessing of spent nuclear fuel. In the earlier reprocessing flow sheet ferrous sulphamate has been used for valancy adjustment of Pu from IV to III for effective separation. This has resulted in generation of HLW containing significance amount of sulphate. Internationally borosilicate glass matrix has been adopted for vitrification of HLW. The first Indian vitrification facility at Waste Immobilislition Plant (WIP), Tarapur a five component borosilicate matrix (SiO 2 :B 2 O 3 :Na 2 O : MnO : TiO 2 ) has been used for vitrification of waste. However at Trombay HLW contain significant amount of sulphate which is not compatible with standard borosilicate formulation. Extensive R and D efforts were made to develop a glass formulation which can accommodate sulphate and other constituents of HLW e.g., U, Al, Ca, etc. This report deals with development work of a glass formulations for immobilization of sulphate bearing waste. Different glass formulations were studied to evaluate the compatibility with respect to sulphate and other constituents as mentioned above. This includes sodium, lead and barium borosilicate glass matrices. Problems encountered in different glass matrices for containment of sulphate have also been addressed. A glass formulation based on barium borosilicate was found to be effective and compatible for sulphate bearing high level waste. (author)

  6. Glass: a candidate engineered material for management of high level nuclear waste

    Mishra, R.K.; Kaushik, C.P.

    2011-01-01

    While the commercial importance of glass is generally recognized, a few people are aware of extremely wide range of glass formulations that can be made and of the versatility of this engineered material. Some of the recent developments in the field of glass leading to various technological applications include glass fiber reinforcement of cement to give new building materials, substrates for microelectronics circuitry in form of semiconducting glasses, nuclear waste immobilization and specific medical applications. The present paper covers fundamental understanding of glass structure and its application for immobilization of high level radioactive liquid waste. High level radioactive liquid waste (HLW) arising during reprocessing of spent fuel are immobilized in sodium borosilicate glass matrix developed indigenously. Glass compositions are modified according to the composition of HLW to meet the criteria of desirable properties in terms. These glass matrices have been characterized for different properties like homogeneity, chemical durability, thermal stability and radiation stability. (author)

  7. Influence of aluminium nitride as a foaming agent on the preparation of foam glass-ceramics from high-titanium blast furnace slag

    Shi, Huan; Feng, Ke-qin; Wang, Hai-bo; Chen, Chang-hong; Zhou, Hong-ling

    2016-05-01

    To effectively reuse high-titanium blast furnace slag (TS), foam glass-ceramics were successfully prepared by powder sintering at 1000°C. TS and waste glass were used as the main raw materials, aluminium nitride (AlN) as the foaming agent, and borax as the fluxing agent. The influence of the amount of AlN added (1wt%-5wt%) on the crystalline phases, microstructure, and properties of the produced foam glass-ceramics was studied. The results showed that the main crystal phases were perovskite, diopside, and augite. With increasing AlN content, a transformation from diopside to augite occurred and the crystallinity of the pyroxene phases slightly decreased. Initially, the average pore size and porosity of the foam glass-ceramics increased and subsequently decreased; similarly, their bulk density and compressive strength decreased and subsequently increased. The optimal properties were obtained when the foam glass-ceramics were prepared by adding 4wt% AlN.

  8. Preparation and antibacterial property of silver-containing mesoporous 58S bioactive glass

    Zhu, Hailin; Hu, Chao [Key Laboratory of Fiber Materials and Processing Technology, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Zhang, Fangfang [Zhejiang Provincial Hospital of Traditional Chinese Medicine, Hangzhou 310006 (China); Feng, Xinxing, E-mail: f0712@tom.com [The Quartermaster Research Institute of the General Logistic Department of CPLA, Beijing 100082 (China); Li, Jiuming; Liu, Tao [Key Laboratory of Fiber Materials and Processing Technology, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Chen, Jianyong, E-mail: cjy@zstu.edu.cn [Key Laboratory of Fiber Materials and Processing Technology, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Zhang, Jianchun [The Quartermaster Research Institute of the General Logistic Department of CPLA, Beijing 100082 (China)

    2014-09-01

    The modified mesoporous 58S bioglass (SM58S) was prepared through surface modification of the mesoporous 58S bioglass (M58S) with γ-aminopropyl triethoxysilane (KH550). The results of Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) showed that the amino groups were grafted to the surface of M58S after modification with KH550. The silver-containing SM58S (Ag-SM58S) and M58S (Ag-M58S) were prepared by the dipping method. The Ag{sup +} loading capacity, release rate and antibacterial properties of Ag-SM58S and Ag-M58S were investigated. It is indicated that surface modification of M58S with KH550 can improve the Ag{sup +} loading capacity. The result of antibacterial property showed that Ag-SM58S exhibited significant anti-bacterial effects against Escherichia coli and Staphylococcus aureus. The sustained release of Ag{sup +} from Ag-SM58S for 768 h ensured excellent antibacterial property of Ag-SM58S. In vitro osteoblast proliferation and differentiation tests showed that Ag-SM58S was a good matrix for the growth of osteoblasts. Consequently, the results of the study suggested that Ag-SM58S might be a promising bone repair material. - Highlights: • The amino groups are grafted to the surface of M58S after modification with KH550. • Surface modification of M58S with KH550 can improve the Ag{sup +} loading capacity. • The sustained release of Ag{sup +} from Ag-SM58S ensures good antibacterial property.

  9. Mechanical properties of nuclear waste glasses

    Connelly, A.J.; Hand, R.J.; Bingham, P.A.; Hyatt, N.C.

    2011-01-01

    The mechanical properties of nuclear waste glasses are important as they will determine the degree of cracking that may occur either on cooling or following a handling accident. Recent interest in the vitrification of intermediate level radioactive waste (ILW) as well as high level radioactive waste (HLW) has led to the development of new waste glass compositions that have not previously been characterised. Therefore the mechanical properties, including Young's modulus, Poisson's ratio, hardness, indentation fracture toughness and brittleness of a series of glasses designed to safely incorporate wet ILW have been investigated. The results are presented and compared with the equivalent properties of an inactive simulant of the current UK HLW glass and other nuclear waste glasses from the literature. The higher density glasses tend to have slightly lower hardness and indentation fracture toughness values and slightly higher brittleness values, however, it is shown that the variations in mechanical properties between these different glasses are limited, are well within the range of published values for nuclear waste glasses, and that the surveyed data for all radioactive waste glasses fall within relatively narrow range.

  10. Glass leaching performance

    Chick, L.A.; Turcotte, R.P.

    1983-05-01

    Current understanding of the leaching performance of high-level nuclear waste (HLW) glass is summarized. The empirical model of waste glass leaching behavior developed shows that at high water flow rates the glass leach rate is kinetically limited to a maximum value. At intermediate water flow rates, leaching is limited by the solution concentration of silica and decreases with decreasing water flow rates. Release of soluble elements is controlled by silica dissolution because silica forms the binding network of the glass. At low water flow rates, mass loss rates reach values controlled by formation rates of alteration minerals, or by diffusion of dissolution products through essentially stagnant water. The parameters reviewed with respect to their quantifiable influence on leaching behavior include temperature, pH, leachant composition, glass composition, thermal history, and radiation. Of these, temperature is most important since the rate of mass loss approximately doubles with each 10 0 C increase in dilute solutions. The pH has small effects within the 4 to 10 range. The chemical composition of the leachant is most important with regard to its influence on alteration product formation. Glass composition exhibits the largest effects at high flow rates where improved glasses leach from ten to thirty times slower than glass 76 to 68. The effects of the thermal history (devitrification) of the glass are not likely to be significant. Radiation effects are important primarily in that radiolysis can potentially drive pH values to less than 4. Radiation damage to the glass causes insignificant changes in leaching performance

  11. Preparation of a biomimetic composite scaffold from gelatin/collagen and bioactive glass fibers for bone tissue engineering

    Sharifi, Esmaeel; Azami, Mahmoud [Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Kajbafzadeh, Abdol-Mohammad [Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Pediatric Urology Research Center, Section of Tissue Engineering and Stem Cells Therapy, Department of Pediatric Urology, Children' s Hospital Medical Center, Tehran, Iran (IRI) (Iran, Islamic Republic of); Moztarzadeh, Fatollah [Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran (Iran, Islamic Republic of); Faridi-Majidi, Reza [Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Shamousi, Atefeh; Karimi, Roya [Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Ai, Jafar, E-mail: jafar_ai@tums.ac.ir [Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Brain and Spinal Injury Research Center (BASIR), Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2016-02-01

    Bone tissue is a composite material made of organic and inorganic components. Bone tissue engineering requires scaffolds that mimic bone nature in chemical and mechanical properties. This study proposes a novel method for preparing composite scaffolds that uses sub-micron bioglass fibers as the organic phase and gelatin/collagen as the inorganic phase. The scaffolds were constructed by using freeze drying and electro spinning methods and their mechanical properties were enhanced by using genipin crosslinking agent. Electron microscopy micrographs showed that the structure of composite scaffolds were porous with pore diameters of approximately 70–200 μm, this was again confirmed by mercury porosimetery. These pores are suitable for osteoblast growth. The diameters of the fibers were approximately 150–450 nm. Structural analysis confirmed the formation of desirable phases of sub-micron bioglass fibers. Cellular biocompatibility tests illustrated that scaffolds containing copper ion in the bioglass structure had more cell growth and osteoblast attachment in comparison to copper-free scaffolds. - Highlights: • Fabrication of 45S5 sub-micron bioglass fiber using electrospinning method. • Production of copper doped submicron bioglass fibers on 45S5 bioglass base by electrospinning sol gel route method. • Incorporation of bioglass/Cu-bioglass sub-micron fibers into gelatin/collagen matrix to form biomimetic composite scaffold which were non-cytotoxic according to MTT assay. • Discovering that copper can decrease the glass transition temperatures and enhance osteoblast cell adhesion and viability.

  12. Preparation of a biomimetic composite scaffold from gelatin/collagen and bioactive glass fibers for bone tissue engineering

    Sharifi, Esmaeel; Azami, Mahmoud; Kajbafzadeh, Abdol-Mohammad; Moztarzadeh, Fatollah; Faridi-Majidi, Reza; Shamousi, Atefeh; Karimi, Roya; Ai, Jafar

    2016-01-01

    Bone tissue is a composite material made of organic and inorganic components. Bone tissue engineering requires scaffolds that mimic bone nature in chemical and mechanical properties. This study proposes a novel method for preparing composite scaffolds that uses sub-micron bioglass fibers as the organic phase and gelatin/collagen as the inorganic phase. The scaffolds were constructed by using freeze drying and electro spinning methods and their mechanical properties were enhanced by using genipin crosslinking agent. Electron microscopy micrographs showed that the structure of composite scaffolds were porous with pore diameters of approximately 70–200 μm, this was again confirmed by mercury porosimetery. These pores are suitable for osteoblast growth. The diameters of the fibers were approximately 150–450 nm. Structural analysis confirmed the formation of desirable phases of sub-micron bioglass fibers. Cellular biocompatibility tests illustrated that scaffolds containing copper ion in the bioglass structure had more cell growth and osteoblast attachment in comparison to copper-free scaffolds. - Highlights: • Fabrication of 45S5 sub-micron bioglass fiber using electrospinning method. • Production of copper doped submicron bioglass fibers on 45S5 bioglass base by electrospinning sol gel route method. • Incorporation of bioglass/Cu-bioglass sub-micron fibers into gelatin/collagen matrix to form biomimetic composite scaffold which were non-cytotoxic according to MTT assay. • Discovering that copper can decrease the glass transition temperatures and enhance osteoblast cell adhesion and viability.

  13. Immobilisation of radio cesium loaded ammonium molybdo phosphate in glass matrices

    Yalmali, Vrunda S.; Singh, I.J.; Sathi Sasidharan, N.; Deshingkar, D.S.

    2004-11-01

    Long half life and easy availability from high level wastes make 137 Cesium most economical radiation source. High level liquid waste processing for 137 Cesium removal has become easier due to development of Cesium specific granulated ammonium molybdophosphate (AMP) composite. In such applications, resulting spent composite AMP itself represents high active solid waste and immobilization of these materials in cement may not be acceptable. Studies on immobilization of 137 Cs loaded AMP were taken up in order to achieve twin goals of increasing safety and minimizing processing costs of the final matrix. Studies indicated that phosphate modified sodium borosilicate SPNM glasses prepared under usual oxidizing conditions are not suitable for immobilization of 137 Cs loaded on AMP .Phosphate glasses containing Na 2 O, P 2 O 5 , B 2 O 3 , Fe 2 O 3 , Al 2 O 3 and SiO 2 as major constituents are capable of incorporating 6 to 8 % AMP. The Normalized Leach rates of these glasses for sodium, cesium, boron and silica are 10 -4 to 10 -6 gm/cm 2 /day which are comparable to or better than those reported for NBS glasses incorporating HLW. Homogeneity of the final matrix was confirmed by x-ray diffraction analysis. Further studies on characterization of these glasses would establish their acceptability. (author)

  14. Initiating the Validation of CCIM Processability for Multi-phase all Ceramic (SYNROC) HLW Form: Plan for Test BFY14CCIM-C

    Maio, Vince [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-08-01

    This plan covers test BFY14CCIM-C which will be a first–of–its-kind demonstration for the complete non-radioactive surrogate production of multi-phase ceramic (SYNROC) High Level Waste Forms (HLW) using Cold Crucible Induction Melting (CCIM) Technology. The test will occur in the Idaho National Laboratory’s (INL) CCIM Pilot Plant and is tentatively scheduled for the week of September 15, 2014. The purpose of the test is to begin collecting qualitative data for validating the ceramic HLW form processability advantages using CCIM technology- as opposed to existing ceramic–lined Joule Heated Melters (JHM) currently producing BSG HLW forms. The major objectives of BFY14CCIM-C are to complete crystalline melt initiation with a new joule-heated resistive starter ring, sustain inductive melting at temperatures between 1600 to 1700°C for two different relatively high conductive materials representative of the SYNROC ceramic formation inclusive of a HLW surrogate, complete melter tapping and pouring of molten ceramic material in to a preheated 4 inch graphite canister and a similar canister at room temperature. Other goals include assessing the performance of a new crucible specially designed to accommodate the tapping and pouring of pure crystalline forms in contrast to less recalcitrant amorphous glass, assessing the overall operational effectiveness of melt initiation using a resistive starter ring with a dedicated power source, and observing the tapped molten flow and subsequent relatively quick crystallization behavior in pans with areas identical to standard HLW disposal canisters. Surrogate waste compositions with ceramic SYNROC forming additives and their measured properties for inductive melting, testing parameters, pre-test conditions and modifications, data collection requirements, and sampling/post-demonstration analysis requirements for the produced forms are provided and defined.

  15. Development of geological disposal system; localization of element cost data and cost evaluation on the HLW repository

    Lee, Byung Sik; Kim, Kil Jung; Yang, Young Jin; Kim, Sung Chun [KOPEC, Taejeon (Korea)

    2002-03-01

    To estimate Total Life Cycle Cost (TSLCC) for Korea HLW Repository through localization of element cost data, we review and re-organize each basic element cost data for reference repository system, localize various element cost and finally estimate TSLCC considering economic parameters. As results of the study, TSLCC is estimated as 17,167,689 million won, which includes costs for site preparation, surface facilities, underground facilities and management/integration. Since HLW repository Project is an early stage of pre-conceptual design at present, the information of design and project information are not enough to perform cost estimate and cost localization for the Project. However, project cost structure is re-organized based on the local condition and Total System Life Cycle Cost is estimated using the previous cost data gathered from construction experience of the local nuclear power plant. Project results can be used as basic reference data to assume total construction cost for the local HLW repository and should be revised to more reliable cost data with incorporating detail project design information into the cost estimate in a future. 20 refs. (Author)

  16. Small Scale Mixing Demonstration Batch Transfer and Sampling Performance of Simulated HLW - 12307

    Jensen, Jesse; Townson, Paul; Vanatta, Matt [EnergySolutions, Engineering and Technology Group, Richland, WA, 99354 (United States)

    2012-07-01

    The ability to effectively mix, sample, certify, and deliver consistent batches of High Level Waste (HLW) feed from the Hanford Double Shell Tanks (DST) to the Waste treatment Plant (WTP) has been recognized as a significant mission risk with potential to impact mission length and the quantity of HLW glass produced. At the end of 2009 DOE's Tank Operations Contractor, Washington River Protection Solutions (WRPS), awarded a contract to EnergySolutions to design, fabricate and operate a demonstration platform called the Small Scale Mixing Demonstration (SSMD) to establish pre-transfer sampling capacity, and batch transfer performance data at two different scales. This data will be used to examine the baseline capacity for a tank mixed via rotational jet mixers to transfer consistent or bounding batches, and provide scale up information to predict full scale operational performance. This information will then in turn be used to define the baseline capacity of such a system to transfer and sample batches sent to WTP. The Small Scale Mixing Demonstration (SSMD) platform consists of 43'' and 120'' diameter clear acrylic test vessels, each equipped with two scaled jet mixer pump assemblies, and all supporting vessels, controls, services, and simulant make up facilities. All tank internals have been modeled including the air lift circulators (ALCs), the steam heating coil, and the radius between the wall and floor. The test vessels are set up to simulate the transfer of HLW out of a mixed tank, and collect a pre-transfer sample in a manner similar to the proposed baseline configuration. The collected material is submitted to an NQA-1 laboratory for chemical analysis. Previous work has been done to assess tank mixing performance at both scales. This work involved a combination of unique instruments to understand the three dimensional distribution of solids using a combination of Coriolis meter measurements, in situ chord length distribution

  17. Effect of ThO2 concentration on thermo-physical properties of barium borosilicate glass

    Mishra, R.K.; Munshi, A.K.; Kaushik, C.P.; Raj, Kanwar; Shobha, M.; Srikhande, V.K.; Kothiyal, G.P.; Tyagi, A.K.

    2006-01-01

    An advanced heavy water reactor is being developed at Bhabha Atomic Research Centre (BARC) India with an aim of utilizing thorium for power generation. The high level radioactive liquid waste (HLW) generated from reprocessing of Th-based spent fuel is expected to contain Th as one of the main constituents other than fission products, corrosion products, actinides and added chemicals. Barium borosilicate (BBS) glass is being used for vitrification of the HLW generated at the reprocessing plant at BARC, Trombay, Mumbai

  18. Test plan: Effects of phase separation on waste loading for high level waste glasses

    Jantzen, C.M.

    2000-01-01

    As part of the Tanks Focus Area's (TFA) effort to increase waste loading for high-level waste (HLW) vitrification at various facilities in the Department of Energy (DOE) complex, the occurrence of phase separation in waste glasses spanning the Savannah River Site (SRS) and Idaho National Engineering and Environmental Laboratory (INEEL) composition ranges were studied during FY99. The type, extent, and impact of phase separation on glass durability for a series of HLW glasses, e.g., SRS-type and INEEL-type, were examined

  19. Solidification of HLLW by glass-ceramic process

    Oguino, N.; Masuda, S.; Tsunoda, N.; Yamanaka, T.; Ninomiya, M.; Sakane, T.; Nakamura, S.; Kawamura, S.

    1979-01-01

    The compositions of glass-ceramics for the solidification of HLLW were studied, and the glass-ceramics in the diopside system was concluded to be the most suitable. Compared with the properties of HLW borosilicate glasses, those of diopside glass-ceramic were thought to be almost equal in leach rate and superior in thermal stability and mechanical strength. It was also found that the glass in this system can be crystallized simply by pouring it into a thermally insulated canister and then allowing it to cool to room temperature. 2 figures, 5 tables

  20. Waste Isolation Pilot Plant in situ experimental program for HLW

    Molecke, M.A.

    1977-01-01

    The Waste Isolation Pilot Plant (WIPP) will be a facility to demonstrate the environmental and operational safety of storing radioactive wastes in a deep geologic bedded salt facility. The WIPP will be located in southeastern New Mexico, approximately 30 miles east of the city of Carlsbad. The major focus of the pilot plant operation involves ERDA defense related low and intermediate-level transuranic wastes. The scope of the project also specifically includes experimentation utilizing commercially generated high-level wastes, or alternatively, spent unreprocessed fuel elements. WIPP HLW experiments are being conducted in an inter-related laboratory, bench-scale, and in situ mode. This presentation focuses on the planned in situ experiments which, depending on the availability of commercially reprocessed waste plus delays in the construction schedule of the WIPP, will begin in approximately 1985. Such experiments are necessary to validate preceding laboratory results and to provide actual, total conditions of geologic storage which cannot be adequately simulated. One set of planned experiments involves emplacing bare HLW fragments into direct contact with the bedded salt environment. A second set utilizes full-size canisters of waste emplaced in the salt in the same manner as planned for a future HLW repository. The bare waste experiments will study in an accelerated manner waste-salt bed-brine interactions including matrix integrity/degradation, brine leaching, system chemistry, and potential radionuclide migration through the salt bed. Utilization of full-size canisters of HLW in situ permits us to demonstrate operational effectiveness and safety. Experiments will evaluate corrosion and compatibility interactions between the waste matrix, canister and overpack materials, getter materials, stored energy, waste buoyancy, etc. Using full size canisters also allows us to demonstrate engineered retrievability of wastes, if necessary, at the end of experimentation

  1. TWRS HLW interim storage facility search and evaluation

    Calmus, R.B., Westinghouse Hanford

    1996-05-16

    The purpose of this study was to identify and provide an evaluation of interim storage facilities and potential facility locations for the vitrified high-level waste (HLW) from the Phase I demonstration plant and Phase II production plant. In addition, interim storage facilities for solidified separated radionuclides (Cesium and Technetium) generated during pretreatment of Phase I Low-Level Waste Vitrification Plant feed was evaluated.

  2. Management strategy for site characterization at candidate HLW repository sites

    Bartlett, J.W.

    1988-01-01

    This paper describes a management strategy for HLW repository site characterization which is aimed at producing an optimal characterization trajectory for site suitability and licensing evaluations. The core feature of the strategy is a matrix of alternative performance targets and alternative information-level targets which can be used to allocate and justify program effort. Strategies for work concerning evaluation of expected and disrupted repository performance are distinguished, and the need for issue closure criteria is discussed

  3. Glass Formulation For The Hanford Tank Waste Treatment And Immobilization Plant (WTP)

    Kruger, A.A.; Jain, V.

    2009-01-01

    A computational method for formulating Hanford HLW glasses was developed that is based on empirical glass composition-property models, accounts for all associated uncertainties, and can be solved in Excel R in minutes. Calculations for all waste form processing and compliance requirements included. Limited experimental validation performed.

  4. GLASS FORMULATION FOR THE HANFORD TANK WASTE TREATMENT AND IMMOBILIZATION PLANT (WTP)

    KRUGER AA; VIENNA JD; KIM DS; JAIN V

    2009-05-27

    A computational method for formulating Hanford HLW glasses was developed that is based on empirical glass composition-property models, accounts for all associated uncertainties, and can be solved in Excel{sup R} in minutes. Calculations for all waste form processing and compliance requirements included. Limited experimental validation performed.

  5. Durability, mechanical, and thermal properties of experimental glass-ceramic forms for immobilizing ICPP high level waste

    Vinjamuri, K.

    1990-01-01

    The high-level liquid waste generated at the Idaho Chemical Processing Plant (ICPP) is routinely solidified into granular calcined high-level waste (HLW) and stored onsite. Research is being conducted at the ICPP on methods of immobilizing the HLW, including developing a durable glass-ceramic form which has the potential to significantly reduce the final waste volume by up to 60% compared to a glass form. Simulated, pilot plant, non-radioactive, calcines similar to the composition of the calcined HLW and glass forming additives are used to produce experimental glass-ceramic forms. The objective of the research reported in this paper is to study the impact of ground calcine particle size on durability and mechanical and thermal properties of experimental glass-ceramic forms

  6. R and D programme for HLW disposal in Japan

    Tsuboya, Takao

    1997-01-01

    The Power Reactor and Nuclear Fuel Development Corporation (PNC) has been active in developing an R and D programme for high-level radioactive waste (HLW) disposal in accordance with the overall HLW management programme defined by the Atomic Energy Commission (AEC) of Japan. The aim of the R and D activities at the current stage is to provide a scientific and technical basis for the geological disposal of HLW in Japan, which is turn promotes understanding of the safety concept not only in the scientific and technical community but also by the general public. As a major milestone in the R and D programme, PNC submitted a first progress report, referred to as H3, in September 1992. H3 summarised the results of R and D activities up to March 1992 and identified priority issues for further study. The second progress report, scheduled to be submitted around 2000, and should demonstrated more rigorously and transparently the feasibility of the specified disposal concept. It should also provide input for the siting and regulatory processes, which will be set in motion after the year 2000. (author). 10 refs., 4 figs

  7. Production of glass or glass-ceramic to metal seals with the application of pressure

    Kelly, Michael D.; Kramer, Daniel P.

    1987-11-10

    In a process for preparing a glass or glass-ceramic to metal seal comprising contacting the glass with the metal and heat-treating the glass and metal under conditions whereby the glass to metal seal is effected and, optionally, the glass is converted to a glass-ceramic, an improvement comprises carrying out the heat-treating step using hot isostatic pressing.

  8. High content silicate porous glasses used for radioactive wastes storage: preparation and characterization of the spinodal decomposition

    Ventura, P.C.S.

    1983-01-01

    The phase separation behavior via spinodal decomposition of two sodium borosilicate glasses has been studied having the following compositions in weight %: Glass A: 8% Na 2 O - 32% B 2O3 - 60% Si O 2 Glass 8% B: Na 2 O -27% B 2 O 3 - 65% Si O 2 . The growth of the mean size r of the minor phase microstructure has been determined as a function of both the time length (0-100 hours) and the heat treatment by analyzing temperature 580, 600 0 C of the glass sample images obtained with a Scanning Electron Microscope. The results are in good agreement with the theory of Lifshitz-Slyozov which predict a growth of the minor phase microstructure via a diffusion controlled process through the insoluble phase such that r-bar = A o t e - ΔE/R T. The activation energy ΔE and the pre-exponential factor A o of the diffusion process were found ΔE = 58,8 kCal/mol; A o = 8,42 x 10 21 Angstrom 3 /h for the glass A and ΔE = 92,6 kCal/mol; A o = 4,84 x 10 29 Angstrom 3 /h for the glass B. The distribution curves of the microstructure size allowed to suggest for the glasses under study the most adequate heat treatments to absorbs after the leaching of the soluble phase. (author)

  9. Preparation and properties of yttrium iron garnet microcrystal in $P_{2}O_{5}-MgO$ glass

    Chen, G J; Chang, Y S; Lee, H M; Lin, Y J; 10.1016/j.jallcom.2004.07.041

    2005-01-01

    The fabrication of phosphorus-based glasses containing Y/sub 3/Fe/sub 5/O/sub 12/ crystals by the incorporation method was studied. From transmission electron microscopy observation, there is only one rod- like crystalline phase identified as Y/sub 3/Fe/sub 5/O/sub 12/ existing in the glass matrix. When the content of YIG is 30wt.%, the as-cast sample shows a Faraday rotation of 85 degrees /cm and a magnetization of 0.4emu/g in a field of 14kOe. After heat treatment, the magnetic and optical properties of the glass ceramic changed owing to the thermal diffusion of iron ions into the glass matrix.

  10. Bright white upconversion luminescence from Er3+/Tm3+/Yb3+-doped titanate-based glasses prepared by aerodynamic levitation method

    Zhang, Minghui; Yu, Jianding; Jiang, Wan; Liu, Yan; Ai, Fei; Wen, Haiqin; Jiang, Meng; Yu, Huimei; Pan, Xiuhong; Tang, Meibo; Gai, Lijun

    2017-10-01

    Aerodynamic levitation method was employed to prepare Er3+/Tm3+/Yb3+-doped titanate-based glasses. DTA results show that the glass performs high thermal stability with the glass transition temperature of 799 °C. The interaction among rare earth ions has been discussed by adjusting the relative concentration. Er3+ ions can quench the upconversion luminescence of Tm3+ ions. Tm3+ ions play a strong role in quenching the emissions of Er3+ and Tm3+ when the content of Tm3+ ions is greater than or equal 0.05. From the view of the ratio of red emission to green emission, Tm3+ ions can improve the red emission of Er3+ ions to some extent in contrast with the green emissions of Er3+ ions. 980 nm incident laser can be efficiently absorbed by Yb3+ ions. The relative intensity of red, green, and blue upconversion luminescence has been tuned to obtain white light. The composition with white upconversion luminescence of the color coordinate (0.291, 0.3292) has been found. Moreover, white upconversion luminescence mechanism is a two-photon process of ET, ESA, and cooperative sensitization. Rare earth ions doped titanate-based glasses with bright upconversion luminescence perform potential applications in color display, back light, et al.

  11. Characterization of a wollastonite glass-ceramic material prepared using sugar cane bagasse ash (SCBA) as one of the raw materials

    Teixeira, Silvio R., E-mail: rainho@fct.unesp.br [Universidade Estadual Paulista — UNESP, Faculdade de Ciências e Tecnologia — FCT, 19060-900 Presidente Prudente — SP (Brazil); Souza, Agda E. [Universidade Estadual Paulista — UNESP, Faculdade de Ciências e Tecnologia — FCT, 19060-900 Presidente Prudente — SP (Brazil); Carvalho, Claudio L.; Reynoso, Victor C.S. [Universidade Estadual Paulista — UNESP, Faculdade de Engenharia de Ilha Solteira — FEIS, 15385-000 Ilha Solteira – SP (Brazil); Romero, Maximina; Rincón, Jesús Ma. [Instituto de Ciencias de la Construccion Eduardo Torroja — IETCC, CSIC, 28033 Madrid (Spain)

    2014-12-15

    Glass-ceramic material prepared with sugar cane bagasse ash as one of the raw materials was characterized to determine some important properties for its application as a coating material. X-ray diffraction patterns showed that wollastonite-2M (CaSiO{sub 3}) was the major glass-ceramic phase. The Rietveld method was used to quantify the crystalline (60 wt.%) and vitreous (40 wt.%) phases in the glass-ceramic. The microstructure (determined by scanning electron microscopy) of this material had a marble appearance, showing a microporous network of elongated crystals with some areas with dendritic, feather-like ordering. Microhardness data gave a mean hardness value of 564.4 HV (Vickers-hardness), and light microscopy disclosed a greenish brown colored material with a vitreous luster. - Highlights: • We studied the properties of a glass-ceramic material obtained from sugarcane ash. • This material has the appearance and hardness of natural stones. • A refining method gave information about its amorphous and crystalline phases. • This material has potential to be used as coating plates for buildings.

  12. Characterization of a wollastonite glass-ceramic material prepared using sugar cane bagasse ash (SCBA) as one of the raw materials

    Teixeira, Silvio R.; Souza, Agda E.; Carvalho, Claudio L.; Reynoso, Victor C.S.; Romero, Maximina; Rincón, Jesús Ma.

    2014-01-01

    Glass-ceramic material prepared with sugar cane bagasse ash as one of the raw materials was characterized to determine some important properties for its application as a coating material. X-ray diffraction patterns showed that wollastonite-2M (CaSiO 3 ) was the major glass-ceramic phase. The Rietveld method was used to quantify the crystalline (60 wt.%) and vitreous (40 wt.%) phases in the glass-ceramic. The microstructure (determined by scanning electron microscopy) of this material had a marble appearance, showing a microporous network of elongated crystals with some areas with dendritic, feather-like ordering. Microhardness data gave a mean hardness value of 564.4 HV (Vickers-hardness), and light microscopy disclosed a greenish brown colored material with a vitreous luster. - Highlights: • We studied the properties of a glass-ceramic material obtained from sugarcane ash. • This material has the appearance and hardness of natural stones. • A refining method gave information about its amorphous and crystalline phases. • This material has potential to be used as coating plates for buildings

  13. Preparation of soda-lime glass using rock wool waste; Preparacao de vidros sodo-calcicos utilizando residuo de la de rocha

    Aleixo, F.C.; Della, V.P. [Instituto Federal do Espirito Santo, Vitoria, ES (Brazil); Ballmann, T.J.S.; Folgueras, M.V. [Universidade do Estado de Santa Catarina (UESC), Joinville, SC (Brazil); Junkes, J.A., E-mail: janajunkes@gmail.com [Centro Universitario Tiradentes, Maceio, AL (Brazil)

    2016-10-15

    Discarded by the mining industry during the maintenance stoppages of pelletizing furnaces, rock wool has in its composition SiO{sub 2} (56%), Na{sub 2} O (12%) and CaO (7%) propitious for obtaining soda-lime glasses. Under this focus, this work developed soda-lime glasses formulations, using as main raw-material rock wool waste in proportions from 50 to 100% by adjusting the chemical composition of the formulations with sand, sodium and calcium carbonates, as silica, soda and lime sources, respectively. In some formulations the sodium carbonate was replaced by sodium sulfate, which acts as a refining agent, improving homogenization and reducing the bubble formation during the melting. Initially, the raw-materials were evaluated by X-ray fluorescence, X-ray diffraction, differential thermal analysis, and thermogravimetric analysis. The tests showed that the rock wool waste has potential to be used in soda-lime glasses production, however, the chemical composition must be corrected. After knowing the waste potential, seven mixtures were prepared and molten at 1550 °C for 1 to 2 h. It has been found that the maximum rock wool waste percentage that can be used is between 60 and 80%, and that the 2 h melting time resulted in more homogeneous glasses and fewer bubbles according to the addition of sodium sulfate which is efficient for bubbles removal. (author)

  14. Preparation of lead oxide nanoparticles from cathode-ray tube funnel glass by self-propagating method.

    Wang, Yu; Zhu, Jianxin

    2012-05-15

    This paper presents a novel process of extracting lead oxide nanoparticles from cathode-ray tube (CRT) funnel glass using self-propagating high-temperature synthesis (SHS) method. The impacts of added amount of funnel glass on the extraction ratio of lead, the lead extraction velocity and the micromorphology, as well as particle size of extracted nanoparticles were investigated. We found that self-propagating reaction in the presence of Mg and Fe(2)O(3) could separate lead preferentially and superfine lead oxide nanoparticles were obtained from a collecting chamber. The separation ratio was related closely to the amount of funnel glass added in the original mixture. At funnel glass addition of no more than 40wt.%, over 90wt.% of lead was recovered from funnel glass. High extraction yield reveals that the network structure of funnel glass was fractured due to the dramatic energy generated during the SHS melting process. The PbO nanoparticles collected show good dispersion and morphology with a mean grain size of 40-50nm. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Focusing on clay formation as host media of HLW geological disposal in China

    Zheng Hualing; Chen Shi; Sun Donghui

    2007-01-01

    Host medium is vitally important for safety for HLW geological disposal. Chinese HLW disposal effort in the past decades were mainly focused on granite formation. However, the granite formation has fatal disadvantage for HLW geological disposal. This paper reviews experiences gained and lessons learned in the international community and analyzes key factors affecting the site selection. It is recommended that clay formation should be taken into consideration and additional effort should be made before decision making of host media of HLW disposal in China. (authors)

  16. Final Report Determination Of The Processing Rate Of RPP-WTP HLW Simulants Using A Duramelter J 1000 Vitrification System VSL-00R2590-2, Rev. 0, 8/21/00

    Kruger, A.A.; Matlack, K.S.; Kot, W.K.; Perez-Cardenas, F.; Pegg, I.L.

    2011-01-01

    This report provides data, analysis, and conclusions from a series of tests that were conducted at the Vitreous State Laboratory of The Catholic University of America (VSL) to determine the melter processing rates that are achievable with RPP-WTP HLW simulants. The principal findings were presented earlier in a summary report (VSL-00R2S90-l) but the present report provides additional details. One of the most critical pieces of information in determining the required size of the RPP-WTP HLW melter is the specific glass production rate in terms of the mass of glass that can be produced per unit area of melt surface per unit time. The specific glass production rate together with the waste loading (essentially, the ratio of waste-in to glass-out, which is determined from glass formulation activities) determines the melt area that is needed to achieve a given waste processing rate with due allowance for system availability. As a consequence of the limited amount of relevant information, there exists, for good reasons, a significant disparity between design-base specific glass production rates for the RPP-WTP LAW and HLW conceptual designs (1.0 MT/m 2 /d and 0.4 MT/m 2 /d, respectively); furthermore, small-scale melter tests with HLW simulants that were conducted during Part A indicated typical processing rates with bubbling of around 2.0 MT/m 2 /d. This range translates into more than a factor of five variation in the resultant surface area of the HLW melter, which is clearly not without significant consequence. It is clear that an undersized melter is undesirable in that it will not be able to support the required waste processing rates. It is less obvious that there are potential disadvantages associated with an oversized melter, over and above the increased capital costs. A melt surface that is consistently underutilized will have poor cold cap coverage, which will result in increased volatilization from the melt (which is generally undesirable) and increased plenum

  17. FINAL REPORT DETERMINATION OF THE PROCESSING RATE OF RPP WTP HLW SIMULANTS USING A DURAMELTER J 1000 VITRIFICATION SYSTEM VSL-00R2590-2 REV 0 8/21/00

    KRUGER AA; MATLACK KS; KOT WK; PEREZ-CARDENAS F; PEGG IL

    2011-12-29

    This report provides data, analysis, and conclusions from a series of tests that were conducted at the Vitreous State Laboratory of The Catholic University of America (VSL) to determine the melter processing rates that are achievable with RPP-WTP HLW simulants. The principal findings were presented earlier in a summary report (VSL-00R2S90-l) but the present report provides additional details. One of the most critical pieces of information in determining the required size of the RPP-WTP HLW melter is the specific glass production rate in terms of the mass of glass that can be produced per unit area of melt surface per unit time. The specific glass production rate together with the waste loading (essentially, the ratio of waste-in to glass-out, which is determined from glass formulation activities) determines the melt area that is needed to achieve a given waste processing rate with due allowance for system availability. As a consequence of the limited amount of relevant information, there exists, for good reasons, a significant disparity between design-base specific glass production rates for the RPP-WTP LAW and HLW conceptual designs (1.0 MT/m{sup 2}/d and 0.4 MT/m{sup 2}/d, respectively); furthermore, small-scale melter tests with HLW simulants that were conducted during Part A indicated typical processing rates with bubbling of around 2.0 MT/m{sup 2}/d. This range translates into more than a factor of five variation in the resultant surface area of the HLW melter, which is clearly not without significant consequence. It is clear that an undersized melter is undesirable in that it will not be able to support the required waste processing rates. It is less obvious that there are potential disadvantages associated with an oversized melter, over and above the increased capital costs. A melt surface that is consistently underutilized will have poor cold cap coverage, which will result in increased volatilization from the melt (which is generally undesirable) and

  18. Glass Property Models and Constraints for Estimating the Glass to be Produced at Hanford by Implementing Current Advanced Glass Formulation Efforts

    Vienna, John D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kim, Dong-Sang [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Skorski, Daniel C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Matyas, Josef [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-07-01

    Recent glass formulation and melter testing data have suggested that significant increases in waste loading in HLW and LAW glasses are possible over current system planning estimates. The data (although limited in some cases) were evaluated to determine a set of constraints and models that could be used to estimate the maximum loading of specific waste compositions in glass. It is recommended that these models and constraints be used to estimate the likely HLW and LAW glass volumes that would result if the current glass formulation studies are successfully completed. It is recognized that some of the models are preliminary in nature and will change in the coming years. Plus the models do not currently address the prediction uncertainties that would be needed before they could be used in plant operations. The models and constraints are only meant to give an indication of rough glass volumes and are not intended to be used in plant operation or waste form qualification activities. A current research program is in place to develop the data, models, and uncertainty descriptions for that purpose. A fundamental tenet underlying the research reported in this document is to try to be less conservative than previous studies when developing constraints for estimating the glass to be produced by implementing current advanced glass formulation efforts. The less conservative approach documented herein should allow for the estimate of glass masses that may be realized if the current efforts in advanced glass formulations are completed over the coming years and are as successful as early indications suggest they may be. Because of this approach there is an unquantifiable uncertainty in the ultimate glass volume projections due to model prediction uncertainties that has to be considered along with other system uncertainties such as waste compositions and amounts to be immobilized, split factors between LAW and HLW, etc.

  19. Glass compositions

    France, P W

    1985-05-30

    A fluoride glass for use in the production of optical fibres has an enhanced D/H ratio, preferably such that OD:OH is at least 9:1. In the example, such a glass is prepared by treating with D/sub 2/O a melt comprising 51.53 mole per cent ZrF/sub 4/, 20.47 mole per cent BaF/sub 2/, 5.27 mole per cent LaF/sub 3/, 3.24 mole per cent AlF/sub 3/, and 19.49 mole per cent LiF.

  20. Glass formulation for phase 1 high-level waste vitrification

    Vienna, J.D.; Hrma, P.R.

    1996-04-01

    The purpose of this study is to provide potential glass formulations for prospective Phase 1 High-Level Waste (HLW) vitrification at Hanford. The results reported here will be used to aid in developing a Phase 1 HLW vitrification request for proposal (RFP) and facilitate the evaluation of ensuing proposals. The following factors were considered in the glass formulation effort: impact on total glass volume of requiring the vendor to process each of the tank compositions independently versus as a blend; effects of imposing typical values of B{sub 2}O{sub 3} content and waste loading in HLW borosilicate glasses as restrictions on the vendors (according to WAPS 1995, the typical values are 5--10 wt% B{sub 2}O{sub 3} and 20--40 wt% waste oxide loading); impacts of restricting the processing temperature to 1,150 C on eventual glass volume; and effects of caustic washing on any of the selected tank wastes relative to glass volume.

  1. Preparation and investigation of [GeSe4]100-xIx glasses as promising materials for infrared fiber sensors

    Velmuzhov, A. P.; Sukhanov, M. V.; Shiryaev, V. S.; Plekhovich, A. D.; Kotereva, T. V.; Snopatin, G. E.; Gerasimenko, V. V.; Pushkin, A. A.

    2016-10-01

    The glasses of [GeSe4]100-xIx (x = 1, 3, 5, 8, 10) compositions are prepared; their thermal properties, transparency in the mid-IR range and stability against crystallization are investigated. The glass transition temperature (Tg) in this system decreases monotonically with increasing iodine content from the value of Tg = 176 °C at x = 1 to Tg = 129 °C at x = 10. It has been determined by X-ray diffraction method that the addition of iodine reduces the volume fraction of the crystalline phase in glasses after annealing at 350 °C. Using a single crucible technique, the rod of [GeSe4]95I5 glass was drawn into a single-index fiber of 300 μm diameter and 10 m length. The optical losses were 2-3 dB/m in the spectral range 2.5-8 μm; the minimum optical losses were 1.7 dB/m at a wavelength of 5.5 μm. The content of impurity hydrogen in the form of Se-H in the fiber was about 3.6 ppm(wt), impurity oxygen in the form of Ge-O is 1 ppm(wt). The possibility of use of such [GeSe4]95I5 glass single-index fiber for infrared analysis of liquids by example of crude oil and water solutions of acetone has been demonstrated.

  2. Preparation and encapsulation performance of Al_2O_3-SiO_2-B_2O_3 glass-ceramic for high temperature thermal storage

    Li, Ruguang; Zhu, Jiaoqun; Zhou, Weibing; Cheng, Xiaomin; Liu, Fengli

    2017-01-01

    Highlights: • Al_2O_3-B_2O_3-SiO_2 has good chemical durability, corrosion resistance and dense structure. • The material rarely used in high temperature thermal storage. • The material was prepared and characterized in the paper. - Abstract: In this paper, Al_2O_3-SiO_2-B_2O_3 glass-ceramic was prepared and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), further, the porosity was detected by Archimedes principle, thermo physical properties were investigated by differential scanning calorimeter (DSC), respectively. The phase composition was detected by XRD, and the morphology was observed by SEM. The results indicated that the thermal conductivities of the Al_2O_3-SiO_2-B_2O_3 glass-ceramic were between 1.3 and 1.5 W·(m·K)"−"1, and the material had good thermal stability in the range of 300–900 °C. The porosity and apparent density were increased with the temperature. The porosity of Al_2O_3-SiO_2-B_2O_3 glass-ceramic in ranging from 1.2 to 9.6%, the apparent density were between 2.12 and 2.67 g·cm"−"3, and heat capacities were between 0.64 and 0.79 kJ/(kg·K). All the results indicated that the Al_2O_3-SiO_2-B_2O_3 glass-ceramic can be applied as encapsulation material in high temperature latent thermal energy storage.

  3. Rheology of Savannah River site tank 42 HLW radioactive sludge

    Ha, B.C.

    1997-01-01

    Knowledge of the rheology of the radioactive sludge slurries at the Savannah River Site is necessary in order to ensure that they can be retrieved from waste tanks and processed for final disposal. At Savannah River Site, Tank 42 sludge represents on of the first HLW radioactive sludges to be vitrified in the Defense Waste Processing Facility. The rheological properties of unwashed Tank 42 sludge slurries at various solids concentrations were measured remotely in the Shielded Cells at the Savannah River Technology Center using a modified Haake Rotovisco viscometer

  4. Durable Glass For Thousands Of Years

    Jantzen, C.

    2009-01-01

    The durability of natural glasses on geological time scales and ancient glasses for thousands of years is well documented. The necessity to predict the durability of high level nuclear waste (HLW) glasses on extended time scales has led to various thermodynamic and kinetic approaches. Advances in the measurement of medium range order (MRO) in glasses has led to the understanding that the molecular structure of a glass, and thus the glass composition, controls the glass durability by establishing the distribution of ion exchange sites, hydrolysis sites, and the access of water to those sites. During the early stages of glass dissolution, a 'gel' layer resembling a membrane forms through which ions exchange between the glass and the leachant. The hydrated gel layer exhibits acid/base properties which are manifested as the pH dependence of the thickness and nature of the gel layer. The gel layer ages into clay or zeolite minerals by Ostwald ripening. Zeolite mineral assemblages (higher pH and Al 3+ rich glasses) may cause the dissolution rate to increase which is undesirable for long-term performance of glass in the environment. Thermodynamic and structural approaches to the prediction of glass durability are compared versus Ostwald ripening.

  5. DURABLE GLASS FOR THOUSANDS OF YEARS

    Jantzen, C.

    2009-12-04

    The durability of natural glasses on geological time scales and ancient glasses for thousands of years is well documented. The necessity to predict the durability of high level nuclear waste (HLW) glasses on extended time scales has led to various thermodynamic and kinetic approaches. Advances in the measurement of medium range order (MRO) in glasses has led to the understanding that the molecular structure of a glass, and thus the glass composition, controls the glass durability by establishing the distribution of ion exchange sites, hydrolysis sites, and the access of water to those sites. During the early stages of glass dissolution, a 'gel' layer resembling a membrane forms through which ions exchange between the glass and the leachant. The hydrated gel layer exhibits acid/base properties which are manifested as the pH dependence of the thickness and nature of the gel layer. The gel layer ages into clay or zeolite minerals by Ostwald ripening. Zeolite mineral assemblages (higher pH and Al{sup 3+} rich glasses) may cause the dissolution rate to increase which is undesirable for long-term performance of glass in the environment. Thermodynamic and structural approaches to the prediction of glass durability are compared versus Ostwald ripening.

  6. Preparation of Ho3+/Tm3+ Co-doped Lanthanum Tungsten Germanium Tellurite Glass Fiber and Its Laser Performance for 2.0 μm

    Zhou, Dechun; Bai, Xuemei; Zhou, Hang

    2017-03-01

    Ho3+/Tm3+ co-doped 50TeO2-25GeO2-3WO3-5La2O3-3Nb2O5-5Li2O-9BaF2 glass fiber is prepared with the rod-tube drawing method of 15 μm core diameter and 125 μm inner cladding diameter applied in the 2.0 μm-infrared laser. The 2.0 μm luminescence properties of the core glass are researched and the fluorescence intensity variation for different Tm3+ doping concentration is systematically analyzed. The results show that the 2.0 μm luminescence of Ho3+ is greatly influenced by the doping concentration ratio of Ho3+ to Tm3+ and that the maximum fluorescence intensity of the core glass can be obtained and its emission cross section can reach 0.933 × 10-21 cm2 when the sensitized proportion of holmium to thulium is 0.3 to 0.7 (mol%). Simultaneously, the maximum phonon energy of the core glass sample is 753 cm-1, which is significantly lower than that of silicate, gallate and germanate glass and the smaller matrix phonon energy can be conductive to the increase 2.0 μm-band emission intensity. The continuous laser with the maximum laser output power of 0.993 W and 2051 nm -wavelength of 31.9%-slope efficiency is output within the 0.5 m glass fiber and the experiment adopts 1560 nm erbium-doped fiber laser(EDFL) as the pump source and the self-built all-fiber laser. Therefore, the glass fiber has excellent laser characteristics and it is suitable for the 2.0 μm-band laser.

  7. Dielectric properties of glasses prepared by quenching melts of superconducting Bi-Ca-Sr-Cu-O cuprates

    Varma, K. B. R.; Subbanna, G. N.; Ramakrishnan, T. V.; Rao, C. N. R.

    1989-07-03

    Glasses obtained from quenching melts of superconducting bismuth cuprates of the formula Bi/sub 2/(Ca,Sr)/sub /ital n/+1/Cu/sub /ital n//O/sub 2/ital n/+4/ with /ital n/=1 and 3 exhibit novel dielectric properties. They possess relatively high dielectric constants as well as high electrical conductivity. The novel dielectric properties of these cuprate glasses are likely to be of electronic origin. They exhibit a weak microwave absorption due to the presence of microcrystallites.

  8. Bioactive glass-ceramic coatings prepared by pulsed laser deposition from RKKP targets (sol-gel vs melt-processing route)

    Rau, J.V., E-mail: giulietta.rau@ism.cnr.it [Istituto di Struttura della Materia, Consiglio Nazionale delle Ricerche, Via del Fosso del Cavaliere, 100-00133 Rome (Italy); Teghil, R. [Universita della Basilicata, Dipartimento di Chimica ' A.M. Tamburro' , Via dell' Ateneo Lucano, 10-85100 Potenza (Italy); CNR-IMIP U.O.S. di Potenza, Zona Industriale di Tito scalo (PZ) (Italy); Fosca, M. [Istituto di Struttura della Materia, Consiglio Nazionale delle Ricerche, Via del Fosso del Cavaliere, 100-00133 Rome (Italy); Universita di Roma ' La Sapienza' , Dipartimento di Chimica, Piazzale Aldo Moro, 5-00185 Rome (Italy); De Bonis, A. [Universita della Basilicata, Dipartimento di Chimica ' A.M. Tamburro' , Via dell' Ateneo Lucano, 10-85100 Potenza (Italy); CNR-IMIP U.O.S. di Potenza, Zona Industriale di Tito scalo (PZ) (Italy); Cacciotti, I.; Bianco, A. [Universita di Roma ' Tor Vergata' , Dipartimento di Ingegneria Industriale, UR INSTM ' Roma Tor Vergata' , Via del Politecnico, 1-00133 Rome (Italy); Albertini, V. Rossi [Istituto di Struttura della Materia, Consiglio Nazionale delle Ricerche, Via del Fosso del Cavaliere, 100-00133 Rome (Italy); Caminiti, R. [Universita di Roma ' La Sapienza' , Dipartimento di Chimica, Piazzale Aldo Moro, 5-00185 Rome (Italy); Ravaglioli, A. [Parco Torricelli delle Arti e delle Scienze, Via Granarolo, 64-48018 Faenza (Ra) (Italy)

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer Bioactive glass-ceramic coatings for bone tissue repair and regeneration. Black-Right-Pointing-Pointer Pulsed Lased Deposition allowed congruent transfer of target composition to coating. Black-Right-Pointing-Pointer Target was prepared by sol-gel process suitable for compositional tailoring. Black-Right-Pointing-Pointer Titanium, widely used for orthopaedics and dental implants, was used as substrate. Black-Right-Pointing-Pointer The physico-chemical properties of the prepared coatings are reported. -- Abstract: The deposition of innovative glass-ceramic composition (i.e. RKKP) coatings by Pulsed Lased Deposition (PLD) technique is reported. RKKP was synthesised following two methodologies: melt-processing and sol-gel, the latter being particularly suitable to tailor the compositional range. The PLD advantage with respect to other deposition techniques is the congruent transfer of the target composition to the coating. The physico-chemical properties of films were investigated by Scanning Electron and Atomic Force Microscopies, Fourier Transform Infrared Spectroscopy, Angular and Energy Dispersive X-ray Diffraction, and Vickers microhardness. The deposition performed at 12 J/cm{sup 2} and 500 Degree-Sign C allows to prepare crystalline films with the composition that replicates rather well that of the initial targets. The 0.6 {mu}m thin melt-processing RKKP films, possessing the hardness of 25 GPa, and the 4.3 {mu}m thick sol-gel films with the hardness of 17 GPa were obtained.

  9. Immobilization of hazardous and radioactive waste into glass structures

    Wicks, G.G.

    1997-01-01

    As a result of more than three decades of international research, glass has emerged as the material of choice for immobilization of a wide range of potentially hazardous radioactive and non-radioactive materials. The ability of glass structures to incorporate and then immobilize many different elements into durable, high integrity, waste glass products is a direct function of the unique random network structure of the glassy state. Every major country involved with long-term management of high-level radioactive waste (HLW) has either selected or is considering glass as the matrix of choice for immobilizing and ultimately, disposing of the potentially hazardous, high-level radioactive material. There are many reasons why glass is preferred. Among the most important considerations are the ability of glass structures to accommodate and immobilize the many different types of radionuclides present in HLW, and to produce a product that not only has excellent technical properties, but also possesses good processing features. Good processability allows the glass to be fabricated with relative ease even under difficult remote-handling conditions necessary for vitrification of highly radioactive material. The single most important property of the waste glass produced is its ability to retain hazardous species within the glass structure and this is reflected by its excellent chemical durability and corrosion resistance to a wide range of environmental conditions. In addition to immobilization of HLW glass matrices are also being considered for isolation of many other types of hazardous materials, both radioactive as well as nonradioactive. This includes vitrification of various actinides resulting from clean-up operations and the legacy of the cold war, as well as possible immobilization of weapons grade plutonium resulting from disarmament activities. Other types of wastes being considered for immobilization into glasses include transuranic wastes, mixed wastes, contaminated

  10. A novel computer-aided method to fabricate a custom one-piece glass fiber dowel-and-core based on digitized impression and crown preparation data.

    Chen, Zhiyu; Li, Ya; Deng, Xuliang; Wang, Xinzhi

    2014-06-01

    Fiber-reinforced composite dowels have been widely used for their superior biomechanical properties; however, their preformed shape cannot fit irregularly shaped root canals. This study aimed to describe a novel computer-aided method to create a custom-made one-piece dowel-and-core based on the digitization of impressions and clinical standard crown preparations. A standard maxillary die stone model containing three prepared teeth each (maxillary lateral incisor, canine, premolar) requiring dowel restorations was made. It was then mounted on an average value articulator with the mandibular stone model to simulate natural occlusion. Impressions for each tooth were obtained using vinylpolysiloxane with a sectional dual-arch tray and digitized with an optical scanner. The dowel-and-core virtual model was created by slicing 3D dowel data from impression digitization with core data selected from a standard crown preparation database of 107 records collected from clinics and digitized. The position of the chosen digital core was manually regulated to coordinate with the adjacent teeth to fulfill the crown restorative requirements. Based on virtual models, one-piece custom dowel-and-cores for three experimental teeth were milled from a glass fiber block with computer-aided manufacturing techniques. Furthermore, two patients were treated to evaluate the practicality of this new method. The one-piece glass fiber dowel-and-core made for experimental teeth fulfilled the clinical requirements for dowel restorations. Moreover, two patients were treated to validate the technique. This novel computer-aided method to create a custom one-piece glass fiber dowel-and-core proved to be practical and efficient. © 2013 by the American College of Prosthodontists.

  11. Characterization of glass and glass ceramic nuclear waste forms

    Lutze, W.; Borchardt, J.; De, A.K.

    1979-01-01

    Characteristics of solidified nuclear waste forms, glass and glass ceramic compositions and the properties (composition, thermal stability, crystallization, phase behavior, chemical stability, mechanical stability, and radiation effects) of glasses and glass ceramics are discussed. The preparation of glass ceramics may be an optional step for proposed vitrification plants if tailored glasses are used. Glass ceramics exhibit some improved properties with respect to glasses. The overall leach resistance is similar to that of glasses. An increased leach resistance may become effective for single radionuclides being hosted in highly insoluble crystal phases mainly when higher melting temperatures are applicable in order to get more leach resistant residual glass phases. The development of glass ceramic is going on. The technological feasibility is still to be demonstrated. The potential gain of stability when using glass ceramics qualifies the material as an alternative nuclear waste form

  12. The chemical stockpile intergovernmental consultation program: Lessons for HLW public involvement

    Feldman, D.L.

    1991-01-01

    This paper assesses the appropriateness of the US Army's Chemical Stockpile Disposal Program's (CSDP) Intergovernmental Consultation and Coordination Boards (ICCBs) as models for incorporating public concerns in the future siting of HLW repositories by DOE. ICCB structure, function, and implementation are examined, along with other issues relevant to the HLW context. 27 refs

  13. Comparison of risks due to HLW and SURF repositories in bedded salt

    Chu, M.S.Y.; Ortiz, N.R.; Wahi, K.K.

    1983-01-01

    A methodology was developed for use in the analysis of risks from geologic disposal of nuclear wastes. This methodology is applied to two conceptual nuclear waste repositories in bedded salt containing High-Level Waste (HLW) and Spent Un-Reprocessed Fuel (SURF), respectively. A comparison of the risk estimated from the HLW and SURF repositories is presented

  14. Spent fuel and HLW transportation the French experience

    Giraud, J.P.; Charles, J.L.

    1995-01-01

    With 53 nuclear power plants in operation at EDF and a fuel cycle with recycling policy of the valuable materials, COGEMA is faced with the transport of a wide range of radioactive materials. In this framework, the transport activity is a key link in closing the fuel cycle. COGEMA has developed a comprehensive Transport Organization System dealing with all the sectors of the fuel cycle. The paper will describe the status of transportation of spent fuel and HLW in France and the experience gathered. The Transport Organization System clearly defines the role of all actors where COGEMA, acting as the general coordinator, specifies the tasks to be performed and brings technical and commercial support to its various subcontractors: TRANSNUCLEAIRE, specialized in casks engineering and transport operations, supplies packaging and performs transport operations, LEMARECHAL and CELESTIN operate transport by truck in the Vicinity of the nuclear sites while French Railways are in charge of spent fuel transport by train. HLW issued from the French nuclear program is stored for 30 years in an intermediate storage installation located at the La Hague reprocessing plant. Ultimately, these canisters will be transported to the disposal site. COGEMA has set up a comprehensive transport organization covering all operational aspects including adapted procedures, maintenance programs and personnel qualification

  15. NOx AND HETEROGENEITY EFFECTS IN HIGH LEVEL WASTE (HLW)

    Meisel, Dan; Camaioni, Donald M.; Orlando, Thom

    2000-01-01

    We summarize contributions from our EMSP supported research to several field operations of the Office of Environmental Management (EM). In particular we emphasize its impact on safety programs at the Hanford and other EM sites where storage, maintenance and handling of HLW is a major mission. In recent years we were engaged in coordinated efforts to understand the chemistry initiated by radiation in HLW. Three projects of the EMSP (''The NOx System in Nuclear Waste,'' ''Mechanisms and Kinetics of Organic Aging in High Level Nuclear Wastes, D. Camaioni--PI'' and ''Interfacial Radiolysis Effects in Tanks Waste, T. Orlando--PI'') were involved in that effort, which included a team at Argonne, later moved to the University of Notre Dame, and two teams at the Pacific Northwest National Laboratory. Much effort was invested in integrating the results of the scientific studies into the engineering operations via coordination meetings and participation in various stages of the resolution of some of the outstanding safety issues at the sites. However, in this Abstract we summarize the effort at Notre Dame

  16. Analysis for silicon in solution in high level waste glass durability studies

    Lewis, R.A.; Smart, R.St.C.; Dale, L.S.; Levins, D.M.

    1982-01-01

    In comparative studies of the durability of HLW glasses, the measurement of the dissolution of the silicate network, in terms of both rate and extent, is of prime importance. To achieve this, analytical techniques such as colorimetry, flame atomic absorption spectrometry and inductively-coupled plasma emission spectrometry are used. The reliability of these analytical techniques for determination of silicon concentration in dissolution of HLW glasses, is examined. At high concentrations both FAA and ICP are accurate but colorimetry, even with HF pretreatment or NaOH digestion, does not give agreement with ICP. At concentrations below 40 mg l -1 all three methods are reliable. (Auth.)

  17. Calculated leaching of certain fission products from a cylinder of French glass

    Blomqvist, G.

    1977-07-01

    The probable total leaching of the most important fission products and actinides have been tabulated for a cylinder of French HLW glass with approximately 9 percent fission products. The calculations cover the period between 30 and 10000 years after removal from the reactor. The cylinder is of the type planned for the introduction of the HLW into Swedish crystalline rocks. All the components are supposed to have the same leach rate. The calculations also include the probable thickness of eroded glass layer/year. (author)

  18. Highly-ordered mesoporous titania thin films prepared via surfactant assembly on conductive indium-tin-oxide/glass substrate and its optical properties

    Uchida, Hiroshi; Patel, Mehul N.; May, R. Alan; Gupta, Gaurav; Stevenson, Keith J.; Johnston, Keith P.

    2010-01-01

    Highly ordered mesoporous titanium dioxide (titania, TiO 2 ) thin films on indium-tin-oxide (ITO) coated glass were prepared via a Pluronic (P123) block copolymer template and a hydrophilic TiO 2 buffer layer. The contraction of the 3D hexagonal array of P123 micelles upon calcination merges the titania domains on the TiO 2 buffer layer to form mesoporous films with a mesochannel diameter of approximately 10 nm and a pore-to-pore distance of 10 nm. The mesoporous titania films on TiO 2 -buffered ITO/glass featured an inverse mesospace with a hexagonally-ordered structure, whereas the films formed without a TiO 2 buffer layer had a disordered microstructure with submicron cracks because of non-uniform water condensation on the hydrophobic ITO/glass surface. The density of the mesoporous film was 83% that of a bulk TiO 2 film. The optical band gap of the mesoporous titania thin film was approximately 3.4 eV, larger than that for nonporous anatase TiO 2 (∼ 3.2 eV), suggesting that the nanoscopic grain size leads to an increase in the band gap due to weak quantum confinement effects. The ability to form highly-ordered mesoporous titania films on electrically conductive and transparent substrates offers the potential for facile fabrication of high surface area semiconductive films with small diffusion lengths for optoelectronics applications.

  19. Simple and environmentally friendly preparation and size control of silver nanoparticles using an inhomogeneous system with silver-containing glass powder

    Mori, Yasutaka; Tagawa, Toshio; Fujita, Masanori; Kuno, Toyohiko; Suzuki, Satoshi; Matsui, Takemi; Ishihara, Masayuki

    2011-01-01

    A simple, environmentally friendly method for preparing highly size-controlled spherical silver nanoparticles was developed that involved heating a mixture of silver-containing glass powder and an aqueous solution of glucose. The stabilizing agent for silver nanoparticles was found to be caramel, which was generated from glucose when preparing the nanoparticles. The particle size was independent of the reaction time, but it increased proportionally with the square root of the glucose concentration in the range 0.25–8.0 wt% (corresponding to particle sizes of 3.48 ± 1.83 to 20.0 ± 2.76 nm). Difference of the generation mechanism of silver nanoparticles between this inhomogeneous system and a system in which Ag + was homogeneously dispersed was discussed.

  20. Computer Modeling Of High-Level Waste Glass Temperatures Within DWPF Canisters During Pouring And Cool Down

    Amoroso, J.

    2011-01-01

    This report describes the results of a computer simulation study to predict the temperature of the glass at any location inside a DWPF canister during pouring and subsequent cooling. These simulations are an integral part of a larger research focus aimed at developing methods to predict, evaluate, and ultimately suppress nepheline formation in HLW glasses. That larger research focus is centered on holistically understanding nepheline formation in HLW glass by exploring the fundamental thermal and chemical driving forces for nepheline crystallization with respect to realistic processing conditions. Through experimental work, the goal is to integrate nepheline crystallization potential in HLW glass with processing capability to ultimately optimize waste loading and throughput while maintaining an acceptable product with respect to durability. The results of this study indicated severe temperature gradients and prolonged temperature dwell times exist throughout different locations in the canister and that the time and temperatures that HLW glass is subjected to during processing is a function of pour rate. The simulations indicate that crystallization driving forces are not uniform throughout the glass volume in a DWPF (or DWPF-like) canister and illustrate the importance of considering overall kinetics (chemical and thermal driving forces) of nepheline formation when developing methods to predict and suppress its formation in HLW glasses. The intended path forward is to use the simulation data both as a driver for future experimental work and, as an investigative tool for evaluating the impact of experimental results. Simulation data will be used to develop laboratory experiments to more acutely evaluate nepheline formation in HLW glass by incorporating the simulated temperatures throughout the canister into the laboratory experiments. Concurrently, laboratory experiments will be performed to identify nepheline crystallization potential in HLW glass as a function of

  1. Effect of fiber content on flexural properties of glass fiber-reinforced polyamide-6 prepared by injection molding.

    Nagakura, Manamu; Tanimoto, Yasuhiro; Nishiyama, Norihiro

    2017-07-26

    The use of non-metal clasp denture (NMCD) materials may seriously affect the remaining tissues because of the low rigidity of NMCD materials such as polyamides. The purpose of this study was to develop a high-rigidity glass fiber-reinforced thermoplastic (GFRTP) composed of E-glass fiber and polyamide-6 for NMCDs using an injection molding. The reinforcing effects of fiber on the flexural properties of GFRTPs were investigated using glass fiber content ranging from 0 to 50 mass%. Three-point bending tests indicated that the flexural strength and elastic modulus of a GFRTP with a fiber content of 50 mass% were 5.4 and 4.7 times higher than those of unreinforced polyamide-6, respectively. The result showed that the physical characteristics of GFRTPs were greatly improved by increasing the fiber content, and the beneficial effects of fiber reinforcement were evident. The findings suggest that the injection-molded GFRTPs are adaptable to NMCDs because of their excellent mechanical properties.

  2. DEFENSE HIGH LEVEL WASTE GLASS DEGRADATION

    Ebert, W.

    2001-01-01

    The purpose of this Analysis/Model Report (AMR) is to document the analyses that were done to develop models for radionuclide release from high-level waste (HLW) glass dissolution that can be integrated into performance assessment (PA) calculations conducted to support site recommendation and license application for the Yucca Mountain site. This report was developed in accordance with the ''Technical Work Plan for Waste Form Degradation Process Model Report for SR'' (CRWMS M andO 2000a). It specifically addresses the item, ''Defense High Level Waste Glass Degradation'', of the product technical work plan. The AP-3.15Q Attachment 1 screening criteria determines the importance for its intended use of the HLW glass model derived herein to be in the category ''Other Factors for the Postclosure Safety Case-Waste Form Performance'', and thus indicates that this factor does not contribute significantly to the postclosure safety strategy. Because the release of radionuclides from the glass will depend on the prior dissolution of the glass, the dissolution rate of the glass imposes an upper bound on the radionuclide release rate. The approach taken to provide a bound for the radionuclide release is to develop models that can be used to calculate the dissolution rate of waste glass when contacted by water in the disposal site. The release rate of a particular radionuclide can then be calculated by multiplying the glass dissolution rate by the mass fraction of that radionuclide in the glass and by the surface area of glass contacted by water. The scope includes consideration of the three modes by which water may contact waste glass in the disposal system: contact by humid air, dripping water, and immersion. The models for glass dissolution under these contact modes are all based on the rate expression for aqueous dissolution of borosilicate glasses. The mechanism and rate expression for aqueous dissolution are adequately understood; the analyses in this AMR were conducted to

  3. Development of gap filling technique in HLW repository

    Nakashima, Hitoshi; Saito, Akira; Ishii, Takashi; Toguri, Satohito; Okihara, Mitsunobu; Iwasa, Kengo

    2016-01-01

    HLW is supposed to be disposed underground at depths more than 300 m in Japan. Buffer is an artificial barrier that controls radionuclides migrating into the groundwater. The buffer would be made of a natural swelling clay, bentonite. Construction technology for the buffer has been studied for many years, but studies for the gaps surrounding the buffer are little. The proper handling of the gaps is important for guaranteeing the functions of the buffer. In this paper, gap filling techniques using bentonite pellets have been developed in order to the gap having the same performance as the buffer. A new method for manufacturing high-density spherical pellets has been developed to fill the gap higher density ever reported. For the bentonite pellets, the filling performance and how to use were determined. And full-scale filling tests provided availability of the bentonite pellets and filling techniques. (author)

  4. Historical fuel reprocessing and HLW management in Idaho

    Knecht, D.A.; Staiger, M.D.; Christian, J.D.

    1997-01-01

    This article review some of the key decision points in the historical development of spent fuel reprocessing and waste management practices at the Idaho Chemical Processing Plant that have helped ICPP to successfully accomplish its mission safely and with minimal impact on the environment. Topics include ICPP reprocessing development; batch aluminum-uranium dissolution; continuous aluminum uranium dissolution; batch zirconium dissolution; batch stainless steel dissolution; semicontinuous zirconium dissolution with soluble poison; electrolytic dissolution of stainless steel-clad fuel; graphite-based rover fuel processing; fluorinel fuel processing; ICPP waste management consideration and design decisions; calcination technology development; ICPP calcination demonstration and hot operations; NWCF design, construction, and operation; HLW immobilization technology development. 80 refs., 4 figs

  5. Comparing technical concepts for disposal of Belgian vitrified HLW

    Bel, J.; Bock, C. de; Boyazis, J.P.

    2004-01-01

    The choice of a suitable repository design for different categories of radioactive waste is an important element in the decisional process that will eventually lead to the waste disposal in geological ground layers during the next decades. Most countries are in the process of elaborating different technical solutions for their EBS '. Considering possible design alternatives offers more flexibility to cope with remaining uncertainties and allows optimizing some elements of the EBS in the future. However, it is not feasible to continue carrying out detailed studies for a large number of alternative design options. At different stages in the decisional process, choices, even preliminary ones, have to be made. Although the impact of different stakeholders (regulator, waste agencies, waste producers, research centers,...) in making these design choices can differ from one country to another, the choices should be based on sound, objective, clear and unambiguous justification grounds. Moreover, the arguments should be carefully reported and easy to understand by the decision makers. ONDRAF/NIRAS recently elaborated three alternative designs for the disposal of vitrified HLW. These three designs are briefly described in the next section. A first series of technological studies pointed out that the three options are feasible. It would however be unreasonable to continue R and D work on all three alternatives in parallel. It is therefore planned to make a preliminary choice of a reference design for the vitrified HLW in 2003. This selection will depend on the way the alternative design options can be evaluated against a number of criteria, mainly derived from general repository design requirements. The technique of multi-criteria analysis (MCA) will be applied as a tool for making the optimum selection, considering all selection criteria and considering different strategic approaches. This paper describes the used methodology. The decision on the actual selection will be

  6. Glass Composition Constraint Recommendations for Use in Life-Cycle Mission Modeling

    McCloy, John S.; Vienna, John D.

    2010-05-03

    The component concentration limits that most influence the predicted Hanford life-cycle HLW glass volume by HTWOS were re-evaluated. It was assumed that additional research and development work in glass formulation and melter testing would be performed to improve the understanding of component effects on the processability and product quality of these HLW glasses. Recommendations were made to better estimate the potential component concentration limits that could be applied today while technology development is underway to best estimate the volume of HLW glass that will eventually be produced at Hanford. The limits for concentrations of P2O5, Bi2O3, and SO3 were evaluated along with the constraint used to avoid nepheline formation in glass. Recommended concentration limits were made based on the current HLW glass property models being used by HTWOS (Vienna et al. 2009). These revised limits are: 1) The current ND should be augmented by the OB limit of OB ≤ 0.575 so that either the normalized silica (NSi) is less that the 62% limit or the OB is below the 0.575 limit. 2) The mass fraction of P2O5 limit should be revised to allow for up to 4.5 wt%, depending on CaO concentrations. 3) A Bi2O3 concentration limit of 7 wt% should be used. 4) The salt accumulation limit of 0.5 wt% SO3 may be increased to 0.6 wt%. Again, these revised limits do not obviate the need for further testing, but make it possible to more accurately predict the impact of that testing on ultimate HLW glass volumes.

  7. Thermal Conductivity of Foam Glass

    Petersen, Rasmus Rosenlund; König, Jakob; Yue, Yuanzheng

    Due to the increased focus on energy savings and waste recycling foam glass materials have gained increased attention. The production process of foam glass is a potential low-cost recycle option for challenging waste, e.g. CRT glass and industrial waste (fly ash and slags). Foam glass is used...... as thermal insulating material in building and chemical industry. The large volume of gas (porosity 90 – 95%) is the main reason of the low thermal conductivity of the foam glass. If gases with lower thermal conductivity compared to air are entrapped in the glass melt, the derived foam glass will contain...... only closed pores and its overall thermal conductivity will be much lower than that of the foam glass with open pores. In this work we have prepared foam glass using different types of recycled glasses and different kinds of foaming agents. This enabled the formation of foam glasses having gas cells...

  8. Baseline LAW Glass Formulation Testing

    Kruger, Albert A.; Mooers, Cavin; Bazemore, Gina; Pegg, Ian L.; Hight, Kenneth; Lai, Shan Tao; Buechele, Andrew; Rielley, Elizabeth; Gan, Hao; Muller, Isabelle S.; Cecil, Richard

    2013-01-01

    The major objective of the baseline glass formulation work was to develop and select glass formulations that are compliant with contractual and processing requirements for each of the LAW waste streams. Other objectives of the work included preparation and characterization of glasses with respect to the properties of interest, optimization of sulfate loading in the glasses, evaluation of ability to achieve waste loading limits, testing to demonstrate compatibility of glass melts with melter materials of construction, development of glass formulations to support ILAW qualification activities, and identification of glass formulation issues with respect to contract specifications and processing requirements

  9. Improvement of database on glass dissolution

    Hayashi, Maki; Sasamoto, Hiroshi; Yoshikawa, Hideki

    2008-03-01

    In geological disposal system, high-level radioactive waste (HLW) glass is expected to retain radionuclide for the long term as the first barrier to prevent radionuclide release. The advancement of its performance assessment technology leads to the reliability improvement of the safety assessment of entire geological disposal system. For this purpose, phenomenological studies for improvement of scientific understanding of dissolution/alteration mechanisms, and development of robust dissolution/alteration model based on the study outcomes are indispensable. The database on glass dissolution has been developed for supporting these studies. This report describes improvement of the prototype glass database. Also, this report gives an example of the application of the database for reliability assessment of glass dissolution model. (author)

  10. Liquidus Temperature Data for DWPF Glass

    Piepel, G.F.; Vienna, J.D.; Crum, J.V.; Mika, M.; Hrma, P.

    1999-01-01

    This report provides new liquidus temperature (T L ) versus composition data that can be used to reduce uncertainty in T L calculation for DWPF glass. According to the test plan and test matrix design PNNL has measured T L for 53 glasses within and just outside of the current DWPF processing composition window. The T L database generated under this task will directly support developing and enhancing the current T L process-control model. Preliminary calculations have shown a high probability of increasing HLW loading in glass produced at the SRS and Hanford. This increase in waste loading will decrease the life-cycle tank cleanup costs by decreasing process time and the volume of waste glass produced

  11. Glass Durability Modeling, Activated Complex Theory (ACT)

    CAROL, JANTZEN

    2005-01-01

    atomic ratios is shown to represent the structural effects of the glass on the dissolution and the formation of activated complexes in the glass leached layer. This provides two different methods by which a linear glass durability model can be formulated. One based on the quasi- crystalline mineral species in a glass and one based on cation ratios in the glass: both are related to the activated complexes on the surface by the law of mass action. The former would allow a new Thermodynamic Hydration Energy Model to be developed based on the hydration of the quasi-crystalline mineral species if all the pertinent thermodynamic data were available. Since the pertinent thermodynamic data is not available, the quasi-crystalline mineral species and the activated complexes can be related to cation ratios in the glass by the law of mass action. The cation ratio model can, thus, be used by waste form producers to formulate durable glasses based on fundamental structural and activated complex theories. Moreover, glass durability model based on atomic ratios simplifies HLW glass process control in that the measured ratios of only a few waste components and glass formers can be used to predict complex HLW glass performance with a high degree of accuracy, e.g. an R 2 approximately 0.97

  12. Preparation and Characterization of γ-AgI in Superionic Composite Glasses (AgIx(AgPO31-x

    S. Suminta

    2007-07-01

    Full Text Available The γ-AgI phase was stabilized at room temperature in the composites glasses (AgIx(AgPO31-x with x = 0.6 and 0.7 via rapid quenching of their molten mixture. The measurement of the crystal structure has been carried out using an X-ray Difractometer at the Physics Departement of Ibaraki University, Japan. The micro strain and crystal size are derived from Hall’s equation. The X-ray diffraction pattern shows some Bragg peaks that correspond to the crystalline γ-AgI. By increasing the concentration of AgI, the peak width becomes more narrow and the position shifts to the higher angle. This indicates that the crystalline size and microstrain are increasing. The increase of micro strain (η, and particle size (D will increase the ionic mobility, thus increasing the ionic conductivity. It is concluded that solidification process on melt AgI into glass matrix AgPO3 not only decreases the micro strain and the particle size, but it also increases the ionic conductivity.

  13. Nd3-xBixFe4GaO12 (x = 2, 2.5 films on glass substrates prepared by MOD method

    Yoshida T.

    2014-07-01

    Full Text Available We studied Nd3-XBiXFe4GaO12 films to obtain perpendicular magnetic anisotropy as well as large Faraday effect. NdBi2Fe4GaO12 (Bi2:NIGG and Nd0.5Bi2.5Fe4GaO12 (Bi2.5:NIGG films were obtained on Nd2BiFe4GaO12 (Bi1:NIGG layer prepared on glass substrates by metal-organic decomposition (MOD method. Bi2:NIGG and Bi2.5:NIGG films showed large Faraday rotation angles of 7.5 and 10.5 degree/µm, at a wavelength of 520 nm, respectively. Those films have perpendicular magnetic anisotropy with a coercivity of 350 Oe and a saturation magnetic field of 730 Oe.

  14. A summary report on feed preparation offgas and glass redox data for Hanford waste vitrification plant: Letter report

    Merz, M.D.

    1996-03-01

    Tests to evaluate feed processing options for the Hanford Waste Vitrification Plant (HWVP) were conducted by a number of investigators, and considerable data were acquired for tests of different scale, including recent full-scale tests. In this report, a comparison was made of the characteristics of feed preparation observed in tests of scale ranging from 57 ml to full-scale of 28,000 liters. These tests included Pacific Northwest Laboratory (PNL) laboratory-scale tests, Kernforschungszentrums Karlsruhe (KfK) melter feed preparation, Research Scale Melter (RSM) feed preparation, Integrated DWPF Melter System (IDMS) feed preparation, Slurry Integrated Performance Testing (SIPT) feed preparation, and formic acid addition to Hanford Neutralized Current Acid Waste (NCAW) care samples.' The data presented herein were drawn mainly from draft reports and include system characteristics such as slurry volume and depth, sweep gas flow rate, headspace, and heating and stirring characteristics. Operating conditions such as acid feed rate, temperature, starting pH, final pH, quantities and type of frit, nitrite, nitrate, and carbonate concentrations, noble metal content, and waste oxide loading were tabulated. Offgas data for CO 2 , NO x , N 2 O, NO 2 , H 2 and NH 3 were tabulated on a common basis. Observation and non-observation of other species were also noted

  15. Advanced High-Level Waste Glass Research and Development Plan

    Peeler, David K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Vienna, John D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Schweiger, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fox, Kevin M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-07-01

    The U.S. Department of Energy Office of River Protection (ORP) has implemented an integrated program to increase the loading of Hanford tank wastes in glass while meeting melter lifetime expectancies and process, regulatory, and product quality requirements. The integrated ORP program is focused on providing a technical, science-based foundation from which key decisions can be made regarding the successful operation of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) facilities. The fundamental data stemming from this program will support development of advanced glass formulations, key process control models, and tactical processing strategies to ensure safe and successful operations for both the low-activity waste (LAW) and high-level waste (HLW) vitrification facilities with an appreciation toward reducing overall mission life. The purpose of this advanced HLW glass research and development plan is to identify the near-, mid-, and longer-term research and development activities required to develop and validate advanced HLW glasses and their associated models to support facility operations at WTP, including both direct feed and full pretreatment flowsheets. This plan also integrates technical support of facility operations and waste qualification activities to show the interdependence of these activities with the advanced waste glass (AWG) program to support the full WTP mission. Figure ES-1 shows these key ORP programmatic activities and their interfaces with both WTP facility operations and qualification needs. The plan is a living document that will be updated to reflect key advancements and mission strategy changes. The research outlined here is motivated by the potential for substantial economic benefits (e.g., significant increases in waste throughput and reductions in glass volumes) that will be realized when advancements in glass formulation continue and models supporting facility operations are implemented. Developing and applying advanced

  16. FINAL REPORT INTEGRATED DM1200 MELTER TESTING OF REDOX EFFECTS USING HLW AZ-101 AND C-106/AY-102 SIMULANTS VSL-04R4800-1 REV 0 5/6/

    KRUGER AA; MATLACK KS; GONG W; BARDAKCI T; D' ANGELO NA; LUTZE W; BIZOT PM; CALLOW RA; BRANDYS M; KOT WK; PEGG IL

    2011-12-29

    This report documents melter and off-gas performance results obtained on the DM1200 HLW Pilot Melter during processing of AZ-101 and C-106/AY-102 HLW simulants. The tests reported herein are a subset of three tests from a larger series of tests described in the Test Plan for the work; results from the remaining tests will be reported separately. Three nine day tests, one with AZ-101 and two with C-106/AY-102 feeds were conducted with variable amounts of added sugar to address the effects of redox. The test with AZ-101 included ruthenium spikes to also address the effects of redox on ruthenium volatility. One of tests addressed the effects of increased flow-sheet nitrate levels using C-106/AY-102 feeds. With high nitrate/nitrite feeds (such as WTP LAW feeds), reductants are required to prevent melt foaming and deleterious effects on glass production rates. Sugar is the baseline WTP reductant for this purpose. WTP HLW feeds typically have relatively low nitrate/nitrite content in comparison to the organic carbon content and, therefore, have typically not required sugar additions. However, HLW feed variability, particularly with respect to nitrate levels, may necessitate the use of sugar in some instances. The tests reported here investigate the effects of variable sugar additions to the melter feed as well as elevated nitrate levels in the waste. Variables held constant to the extent possible included melt temperature, bubbling rate, plenum temperature, cold cap coverage, the waste simulant composition, and the target glass composition. The principal objectives of the DM1200 melter testing were to determine the achievable glass production rates for simulated HLW feeds with variable amounts of added sugar and increased nitrate levels; characterize melter off-gas emissions; characterize the performance of the prototypical off-gas system components as well as their integrated performance; characterize the feed, glass product, and off-gas effluents; and perform pre- and

  17. Final Report Integrated DM1200 Melter Testing Of Redox Effects Using HLW AZ-101 And C-106/AY-102 Simulants VSL-04R4800-1, Rev. 0, 5/6/04

    Kruger, A.A.; Matlack, K.S.; Gong, W.; Bardakci, T.; D'Angelo, N.A.; Lutze, W.; Bizot, P.M.; Callow, R.A.; Brandys, M.; Kot, W.K.; Pegg, I.L.

    2011-01-01

    This report documents melter and off-gas performance results obtained on the DM1200 HLW Pilot Melter during processing of AZ-101 and C-106/AY-102 HLW simulants. The tests reported herein are a subset of three tests from a larger series of tests described in the Test Plan for the work; results from the remaining tests will be reported separately. Three nine day tests, one with AZ-101 and two with C-106/AY-102 feeds were conducted with variable amounts of added sugar to address the effects of redox. The test with AZ-101 included ruthenium spikes to also address the effects of redox on ruthenium volatility. One of tests addressed the effects of increased flow-sheet nitrate levels using C-106/AY-102 feeds. With high nitrate/nitrite feeds (such as WTP LAW feeds), reductants are required to prevent melt foaming and deleterious effects on glass production rates. Sugar is the baseline WTP reductant for this purpose. WTP HLW feeds typically have relatively low nitrate/nitrite content in comparison to the organic carbon content and, therefore, have typically not required sugar additions. However, HLW feed variability, particularly with respect to nitrate levels, may necessitate the use of sugar in some instances. The tests reported here investigate the effects of variable sugar additions to the melter feed as well as elevated nitrate levels in the waste. Variables held constant to the extent possible included melt temperature, bubbling rate, plenum temperature, cold cap coverage, the waste simulant composition, and the target glass composition. The principal objectives of the DM1200 melter testing were to determine the achievable glass production rates for simulated HLW feeds with variable amounts of added sugar and increased nitrate levels; characterize melter off-gas emissions; characterize the performance of the prototypical off-gas system components as well as their integrated performance; characterize the feed, glass product, and off-gas effluents; and perform pre- and

  18. Conclusions on the two technical panels on HLW-disposal and waste treatment processes respectively

    Dinkespiller, J.A.; Dejonghe, P.; Feates, F.

    1986-01-01

    The paper reports the concluding panel session at the European Community Conference on radioactive waste management and disposal, Luxembourg 1985. The panel considered the conclusions of two preceeding technical panels on high level waste (HLW) disposal and waste treatment processes. Geological disposal of HLW, waste management, safety assessment of waste disposal, public opinion, public acceptance of the manageability of radioactive wastes, international cooperation, and waste management in the United States, are all discussed. (U.K.)

  19. Legal precedents regarding use and defensibility of risk assessment in Federal transportation of SNF and HLW

    Bentz, E.J. Jr.; Bentz, C.B.; O'Hora, T.D.; Chen, S.Y.

    1997-01-01

    Risk assessment has become an increasingly important and essential tool in support of Federal decision-making regarding the handling, storage, disposal, and transportation of spent nuclear fuel (SNF) and high-level radioactive waste (HLW). This paper analyzes the current statutory and regulatory framework and related legal precedents with regard to SNF and HLW transportation. The authors identify key scientific and technical issues regarding the use and defensibility of risk assessment in Federal decision-making regarding anticipated shipments

  20. The experiment of affective web risk communication on HLW geological disposal

    Kugo, Akihide; Yoshikawa, Eiwa; Wakabayashi, Yasunaga; Shimoda, Hiroshi; Uda, Akinobu; Ito, Kyoko

    2006-01-01

    Dialog mode web contents regarding the HLW risk is effective to altruism. To make it more effectively, we introduced affective elements such as facial expression of character agents and sympathetic response on the BBS by experts, which brought us smooth risk communication. This paper describes the result of preliminary experiments surrounding the affective ways to communicate on the risk of HLW geological disposal, leading to enhance the social cooperation, and the public open experiment for one month on the Web. (author)

  1. Nuclide transport models for HLW repository safety assessment in Finland, Japan, Sweden, and Canada

    Lee, Young Myoung; Kang, Chul Hyung; Hwang, Yong Soo; Choi, Jong Won; Kim, Sung Gi; Koh, Won Il

    1997-10-01

    Disposal and design concepts in such countries as Sweden, Finland, Canada and Japan which have already published safety assessment reports for the HLW repositories have been reviewed mainly in view of nuclide transport models used in their assessment. This kind of review would be very helpful in doing similar research in Korea where research program regarding HLW has been just started. (author). 44 refs., 2 tabs., 30 figs

  2. Rheology of Savannah River site tank 42 and tank 51 HLW radioactive sludges

    Ha, B.C.; Bibler, N.E.

    1996-01-01

    Knowledge of the rheology of the radioactive sludge slurries at the Savannah River Site (SRS) is necessary in order to ensure that they can be retrieved from waste tanks and processed for final disposal. The high activity radioactive wastes stored as caustic slurries at SRS result from the neutralization of acid waste generated from production of nuclear defense materials. During storage, the wastes separate into a supernate layer and a sludge layer. In the Defense Waste Processing Facility (DWPF) at SRS, the radionuclides from the sludge and supernate will be immobilized into borosilicate glass for long term storage and eventual disposal. Before transferring the waste from a storage tank to the DWPF, a portion of the aluminum in the waste sludge will be dissolved and the sludge will be extensively washed to remove sodium. Tank 51 and Tank 42 radioactive sludges represent the first batch of HLW sludge to be processed in the DWPF. This paper presents results of rheology measurements of Tank 51 and Tank 42 at various solids concentrations. The rheologies of Tank 51 and Tank 42 radioactive slurries were measured remotely in the Shielded Cells Operations (SCO) at the Savannah River Technology Center (SRTC) using a modified Haake Rotovisco RV-12 with an M150 measuring drive unit and TI sensor system. Rheological properties of the Tank 51 and Tank 42 radioactive sludges were measured as a function of weight percent solids. The weight percent solids of Tank 42 sludge was 27, as received. Tank 51 sludge had already been washed. The weight percent solids were adjusted by dilution with water or by concentration through drying. At 12, 15, and 18 weight percent solids, the yield stresses of Tank 51 sludge were 5, 11, and 14 dynes/cm2, respectively. The apparent viscosities were 6, 10, and 12 centipoises at 300 sec-1 shear rate, respectively

  3. Current Understanding and Remaining Challenges in Modeling Long-Term Degradation of Borosilicate Nuclear Waste Glasses

    Vienna, John D.; Ryan, Joseph V.; Gin, Stephane; Inagaki, Yaohiro

    2013-01-01

    Chemical durability is not a single material property that can be uniquely measured. Instead it is the response to a host of coupled material and environmental processes whose rates are estimated by a combination of theory, experiment, and modeling. High-level nuclear waste (HLW) glass is perhaps the most studied of any material yet there remain significant technical gaps regarding their chemical durability. The phenomena affecting the long-term performance of HLW glasses in their disposal environment include surface reactions, transport properties to and from the reacting glass surface, and ion exchange between the solid glass and the surrounding solution and alteration products. The rates of these processes are strongly influenced and are coupled through the solution chemistry, which is in turn influenced by the reacting glass and also by reaction with the near-field materials and precipitation of alteration products. Therefore, those processes must be understood sufficiently well to estimate or bound the performance of HLW glass in its disposal environment over geologic time-scales. This article summarizes the current state of understanding of surface reactions, transport properties, and ion exchange along with the near-field materials and alteration products influences on solution chemistry and glass reaction rates. Also summarized are the remaining technical gaps along with recommended approaches to fill those technical gaps

  4. Barium borosilicate glass - a potential matrix for immobilization of sulfate bearing high-level radioactive liquid waste

    Kaushik, C.P.; Mishra, R.K.; Sengupta, P.; Kumar, Amar; Das, D.; Kale, G.B.; Raj, Kanwar

    2006-01-01

    Borosilicate glass formulations adopted worldwide for immobilization of high-level radioactive liquid waste (HLW) is not suitable for sulphate bearing HLW, because of its low solubility in such glass. A suitable glass matrix based on barium borosilicate has been developed for immobilization of sulphate bearing HLW. Various compositions based on different glass formulations were made to examine compatibility with waste oxide with around 10 wt% sulfate content. The vitrified waste product obtained from barium borosilicate glass matrix was extensively evaluated for its characteristic properties like homogeneity, chemical durability, glass transition temperature, thermal conductivity, impact strength, etc. using appropriate techniques. Process parameters like melt viscosity and pour temperature were also determined. It is found that SB-44 glass composition (SiO 2 : 30.5 wt%, B 2 O 3 : 20.0 wt%, Na 2 O: 9.5 wt% and BaO: 19.0 wt%) can be safely loaded with 21 wt% waste oxide without any phase separation. The other product qualities of SB-44 waste glass are also found to be on a par with internationally adopted waste glass matrices. This formulation has been successfully implemented in plant scale

  5. Public Perspectives in the Japanese HLW Disposal Program

    Inatsugu, Shigefumi; Takeuchi, Mitsuo; Kato, Toshiaki [Nuclear Waste Management Organization of Japan (NUNIO), Tokyo (Japan)

    2006-09-15

    Following legislation entitled the 'Specified Radioactive Waste Final Disposal Act', the Nuclear Waste Management Organization of Japan (NUMO) was established in October 2000 as the implementing organization for geological disposal of vitrified high-level waste (HLW). Implementation of NUMO's disposal project will be based on three principles: 1) respecting public initiative and opinion, 2) adopting a stepwise approach and 3) ensuring transparency in information disclosure. NUMO has decided to adopt an open solicitation approach to finding volunteer municipalities for Preliminary Investigation Areas (PIAs). The official announcement of the start of the open solicitation program was made in 2002. Although no official applications had been received from volunteer municipalities by the end of 2005, NUMO has been continuing to carry out various activities aimed specifically at public communication and encouraging dialogue about the deep geological disposal project This paper summarizes the results obtained and lessons learned so far and identifies the issues that NUMO must tackle immediately in the areas of communication and dialogue.

  6. Stress analysis of HLW containers advanced test work Compas project

    Ove Arup and Partners

    1990-01-01

    The Compas project is concerned with the structural performance of metal overpacks which may be used to encapsulate vitrified high-level waste forms before disposal in deep geological repositories. This document describes the activities performed between June and August 1989 forming the advanced test work phase of this project. This is the culmination of two years' analysis and test work to demonstrate whether the analytical ability exists to model containers subjected to realistic loads. Three mild steel containers were designed and manufactured to be one-third scale models of a realistic HLW container, modified to represent the effect of anisotropic loading and to facilitate testing. The containers were tested under a uniform external pressure and all failed by buckling in the mid-body region. The outer surface of each container was comprehensively strain-gauged to provide strain history data at all positions of interest. In parallel with the test work, Compas project partners, from five different European countries, independently modelled the behaviour of each of the containers using their computer codes to predict the failure pressure and produce strain history data at a number of specified locations. The first axisymmetric container was well modelled but predictions for the remaining two non-axisymmetric containers were much more varied, with differences of up to 50% occurring between failure predictions and test data

  7. Technical and economic optimization study for HLW waste management

    Deffes, A.

    1989-01-01

    This study was conducted to assess the technical and economic aspects of high level waste (HLW) management with the objective of optimizing the interim storage duration and the dimensions of the underground repository site. The procedure consisted in optimizing the economic criterion under specified constraints. The results are intended to identify trends and guide the choice from among available options; simple and highly flexible models were therefore used in this study, and only nearfield thermal constraints were taken into consideration. Because of the present uncertainty on the physicochemical properties of the repository environment and on the unit cost figures, this study focused on developing a suitable method rather than on obtaining definitive results. With the physical and economic data bases used for the two media investigated (granite and salt) the optimum values found show that it is advisable to minimize the interim storage time, and that the geological repository should feature a high degree of spatial dilution. These results depend to a considerable extent on the assumption of high interim storage costs

  8. Public Perspectives in the Japanese HLW Disposal Program

    Inatsugu, Shigefumi; Takeuchi, Mitsuo; Kato, Toshiaki

    2006-01-01

    Following legislation entitled the 'Specified Radioactive Waste Final Disposal Act', the Nuclear Waste Management Organization of Japan (NUMO) was established in October 2000 as the implementing organization for geological disposal of vitrified high-level waste (HLW). Implementation of NUMO's disposal project will be based on three principles: 1) respecting public initiative and opinion, 2) adopting a stepwise approach and 3) ensuring transparency in information disclosure. NUMO has decided to adopt an open solicitation approach to finding volunteer municipalities for Preliminary Investigation Areas (PIAs). The official announcement of the start of the open solicitation program was made in 2002. Although no official applications had been received from volunteer municipalities by the end of 2005, NUMO has been continuing to carry out various activities aimed specifically at public communication and encouraging dialogue about the deep geological disposal project This paper summarizes the results obtained and lessons learned so far and identifies the issues that NUMO must tackle immediately in the areas of communication and dialogue

  9. Thermal analysis of the vertical disposal for HLW

    Zhao Honggang; Wang Ju; Liu Yuemiao; Su Rui

    2013-01-01

    The temperature on the canister surface is set to be no more than 100℃ in the high level radioactive waste (HLW) repository, it is a criterion to dictate the thermal dimension of the repository. The factors that affect the temperature on the canister surface include the initial power of the canister, the thermal properties of material as the engineered barrier system (EBS), the gaps around the canister in the EBS, the initial ground temperature and thermal properties of the host rock, the repository layout, etc. This article examines the thermal properties of the material in host rock and the EBS, the thermal conductivity properties of the different gaps in the EBS, the temperature evolution around the single canister by using the analysis method and the numerical method. The findings are as follows: 1) The most important and the sensitive parameter is the initial disposal power of the canister; 2) The two key factors that affect the highest temperature on the canister surface are the parameter of uncertainty and nature variability of material as the host rock and the EBS, and the gaps around the canister in the EBS; 3) The temperature difference between the canister and bentonite is no more than 10℃ , and the bigger the inner gaps are, the bigger the temperature difference will be; when the gap between the bentonite and the host rock is filled with water, the temperature difference becomes small, but it will be 1∼3℃ higher than the gaps filled will air. (authors)

  10. Biosphere modelling for a HLW repository - scenario and parameter variations

    Grogan, H.

    1985-03-01

    In Switzerland high-level radioactive wastes have been considered for disposal in deep-lying crystalline formations. The individual doses to man resulting from radionuclides entering the biosphere via groundwater transport are calculated. The main recipient area modelled, which constitutes the base case, is a broad gravel terrace sited along the south bank of the river Rhine. An alternative recipient region, a small valley with a well, is also modelled. A number of parameter variations are performed in order to ascertain their impact on the doses. Finally two scenario changes are modelled somewhat simplistically, these consider different prevailing climates, namely tundra and a warmer climate than present. In the base case negligibly low doses to man in the long term, resulting from the existence of a HLW repository have been calculated. Cs-135 results in the largest dose (8.4E-7 mrem/y at 6.1E+6 y) while Np-237 gives the largest dose from the actinides (3.6E-8 mrem/y). The response of the model to parameter variations cannot be easily predicted due to non-linear coupling of many of the parameters. However, the calculated doses were negligibly low in all cases as were those resulting from the two scenario variations. (author)

  11. Compas project stress analysis of HLW containers intermediate testwork

    Ove Arup and Partners London

    1990-01-01

    The Compas project is concerned with the structural performance of metal overpacks which may be used to encapsulate vitrified high-level waste forms before disposal in deep geological repositories. This document describes the series of experiments and associated calculations performed in the Intermediate testwork phase of this project. Seven mild steel, one-third scale simplified models of HLW containers were manufactured in a variety of configurations of geometry and weld type. The effects of reducing the wall thickness, corroding the external surface of the container, and using different welding methods were all investigated. The containers were tested under the action of a uniform external pressure up to their respective failure points. All containers failed by buckling at pressures of between 42 and 87 MPa dependent upon the particular geometric and weld configuration. The outer surface of each container was comprehensively strain-gauged in order to provide strain histories at positions of interest. The Compas project partners, from five different European countries, independently modelled the behaviour of three of the five different containers. Test results and computer predictions were compared and an assessment of the overall performance of the codes demonstrated good agreement in the initial loading of each container. However once stresses exceeded the material yield point there was a considerable spread in the predicted container behaviour

  12. Rheology of Savannah River Site Tank 51 HLW radioactive sludge

    Ha, B.C.

    1993-01-01

    Savannah River Site (SRS) Tank 51 HLW radioactive sludge represents a major portion of the first batch of sludge to be vitrified in the Defense Waste Processing Facility (DWPF) at SRS. The rheological properties of Tank 51 sludge will determine if the waste sludge can be pumped by the current DWPF process cell pump design and the homogeneity of melter feed slurries. The rheological properties of Tank 51 sludge and sludge/frit slurries at various solids concentrations were measured remotely in the Shielded Cells Operations (SCO) at the Savannah River Technology Center (SRTC) using a modified Haake Rotovisco viscometer system. Rheological properties of Tank 51 radioactive sludge/Frit 202 slurries increased drastically when the solids content was above 41 wt %. The yield stresses of Tank 51 sludge and sludge/frit slurries fall within the limits of the DWPF equipment design basis. The apparent viscosities also fall within the DWPF design basis for sludge consistency. All the results indicate that Tank 51 waste sludge and sludge/frit slurries are pumpable throughout the DWPF processes based on the current process cell pump design, and should produce homogeneous melter feed slurries

  13. Tc Chemistry in HLW: Role of Organic Complexants

    Hess, Nancy S.; Conradsen, Steven D.

    2003-01-01

    Tc complexation with organic compounds in tank waste plays a significant role in the redox chemistry of Tc and the partitioning of Tc between the supernatant and sludge components in waste tanks. These processes need to be understood so that strategies to effectively remove Tc from high-level nuclear waste prior to waste immobilization can be developed and so that long-term consequences of Tc remaining in residual waste after sludge removal can be evaluated. Only limited data on the stability of Tc-organic complexes exists and even less thermodynamic data on which to develop predictive models of Tc chemical behavior is available. To meet these challenges we are conducting a research program to study to develop thermodynamic data on Tc-organic complexation over a wide range of chemical conditions. We will attempt to characterize Tc-speciation in actual tank waste using state-of-the-art analytical organic chemistry, separations, and speciation techniques to validate our model. On the basis of such studies we will develop credible model of Tc chemistry in HLW that will allow prediction of Tc speciation in tank waste and Tc behavior during waste pretreatment processing and in waste tank residuals

  14. 'Practicality' as a key constraint to HLW repository design

    Kitayama, Kazumi; Sakabe, Yasushi; Ishiguro, Katsuhiko

    2007-01-01

    Designs of repositories in Japan for HLW have focused very much on demonstration of post-closure safety. Safety can be assured using very simple assessment techniques, which make many conservative simplifications. Such a situation is reasonable for the early stages of generic concept demonstration, but becomes less appropriate as NUMO moves towards siting, where a number of issues involved with construction and operation of a repository - generally grouped together as 'practicality'. The engineering logistics and conventional safety of repository construction and operation have been relatively little studied and present major challenges. Current designs emphasise a minimum of infrastructure in the emplacement tunnels and remote-handled operation. This would be difficult enough, but such operations need to be carried out to strict quality limits and need to be robust in the event of equipment failure or disruptive events. The paper will first examine how designs can be modified from the viewpoint of logistics. The implications of such modifications on operational robustness and associated safety in case of perturbation scenarios are then considered. (author)

  15. Preparation of CulnS2 Thin Films on the Glass Substrate by DC Sputtering for Solar Cell Component

    Bambang Siswanto; Wirjoadi; Darsono

    2007-01-01

    The CuInS 2 alloys were deposited on glass substrate using plasma DC sputtering technique. A CuInS 2 alloy target was made from Cu, In, Se powder with impurity of 99.998%. The deposition process was done with the following process parameter variations: deposition time and substrate temperature were the range of 15 to 45 min and 150 to 300 ℃, the gas pressure was kept at 1.4x10 -1 Torr. The purpose of the research is to obtain the solar cell component of CuInS 2 thin films. The electrical and optical properties measurement has been done by four-point probe and UV-Vis. Crystal structure was analyzed using X-ray diffraction (XRD). The result shows that minimum resistance of CuInS 2 thin films is 35.7 kΩ and optical transmittance is 14.7 %. The crystal structure of CuInS 2 is oriented at (112) plane and by Touc-plot method was obtained that the band gap energy of thin films is 1.45 eV. It could be concluded that the CuInS 2 thin film can be used as a solar cell component. (author)

  16. Formulation and Characterization of Waste Glasses with Varying Processing Temperature

    Kim, Dong-Sang; Schweiger, M. J.; Rodriguez, Carmen P.; Lepry, William C.; Lang, Jesse B.; Crum, Jarrod V.; Vienna, John D.; Johnson, Fabienne; Marra, James C.; Peeler, David K.

    2011-10-17

    This report documents the preliminary results of glass formulation and characterization accomplished within the finished scope of the EM-31 technology development tasks for WP-4 and WP-5, including WP-4.1.2: Glass Formulation for Next Generation Melter, WP-5.1.2.3: Systematic Glass Studies, and WP-5.1.2.4: Glass Formulation for Specific Wastes. This report also presents the suggested studies for eventual restart of these tasks. The initial glass formulation efforts for the cold crucible induction melter (CCIM), operating at {approx}1200 C, with selected HLW (AZ-101) and LAW (AN-105) successfully developed glasses with significant increase of waste loading compared to that is likely to be achieved based on expected reference WTP formulations. Three glasses formulated for AZ-101HLW and one glass for AN-105 LAW were selected for the initial CCIM demonstration melter tests. Melter tests were not performed within the finished scope of the WP-4.1.2 task. Glass formulations for CCIM were expanded to cover additional HLWs that have high potential to successfully demonstrate the unique advantages of the CCIM technologies based on projected composition of Hanford wastes. However, only the preliminary scoping tests were completed with selected wastes within the finished scope. Advanced glass formulations for the reference WTP melter, operating at {approx}1200 C, were initiated with selected specific wastes to determine the estimated maximum waste loading. The incomplete results from these initial formulation efforts are summarized. For systematic glass studies, a test matrix of 32 high-aluminum glasses was completed based on a new method developed in this study.

  17. Formulation and Characterization of Waste Glasses with Varying Processing Temperature

    Kim, Dong-Sang; Schweiger, M.J.; Rodriguez, Carmen P.; Lepry, William C.; Lang, Jesse B.; Crum, Jarrod V.; Vienna, John D.; Johnson, Fabienne; Marra, James C.; Peeler, David K.

    2011-01-01

    This report documents the preliminary results of glass formulation and characterization accomplished within the finished scope of the EM-31 technology development tasks for WP-4 and WP-5, including WP-4.1.2: Glass Formulation for Next Generation Melter, WP-5.1.2.3: Systematic Glass Studies, and WP-5.1.2.4: Glass Formulation for Specific Wastes. This report also presents the suggested studies for eventual restart of these tasks. The initial glass formulation efforts for the cold crucible induction melter (CCIM), operating at ∼1200 C, with selected HLW (AZ-101) and LAW (AN-105) successfully developed glasses with significant increase of waste loading compared to that is likely to be achieved based on expected reference WTP formulations. Three glasses formulated for AZ-101HLW and one glass for AN-105 LAW were selected for the initial CCIM demonstration melter tests. Melter tests were not performed within the finished scope of the WP-4.1.2 task. Glass formulations for CCIM were expanded to cover additional HLWs that have high potential to successfully demonstrate the unique advantages of the CCIM technologies based on projected composition of Hanford wastes. However, only the preliminary scoping tests were completed with selected wastes within the finished scope. Advanced glass formulations for the reference WTP melter, operating at ∼1200 C, were initiated with selected specific wastes to determine the estimated maximum waste loading. The incomplete results from these initial formulation efforts are summarized. For systematic glass studies, a test matrix of 32 high-aluminum glasses was completed based on a new method developed in this study.

  18. Survey of glass plutonium contents and poison selection

    Plodinec, M.J.; Ramsey, W.G. [Westinghouse Savannah River Company, Aiken, SC (United States); Ellison, A.J.G.; Shaw, H. [Lawrence Livermore National Laboratory, CA (United States)

    1996-05-01

    If plutonium and other actinides are to be immobilized in glass, then achieving high concentrations in the glass is desirable. This will lead to reduced costs and more rapid immobilization. However, glasses with high actinide concentrations also bring with them undersirable characteristics, especially a greater concern about nuclear criticality, particularly in a geologic repository. The key to achieving a high concentration of actinide elements in a glass is to formulate the glass so that the solubility of actinides is high. At the same time, the glass must be formulated so that the glass also contains neutron poisons, which will prevent criticality during processing and in a geologic repository. In this paper, the solubility of actinides, particularly plutonium, in three types of glasses are discussed. Plutonium solubilities are in the 2-4 wt% range for borosilicate high-level waste (HLW) glasses of the type which will be produced in the US. This type of glass is generally melted at relatively low temperatures, ca. 1150{degrees}C. For this melting temperature, the glass can be reformulated to achieve plutonium solubilities of at least 7 wt%. This low melting temperature is desirable if one must retain volatile cesium-137 in the glass. If one is not concerned about cesium volatility, then glasses can be formulated which can contain much larger amounts of plutonium and other actinides. Plutonium concentrations of at least 15 wt% have been achieved. Thus, there is confidence that high ({ge}5 wt%) concentrations of actinides can be achieved under a variety of conditions.

  19. Leaching behavior of simulated high-level waste glass

    Kamizono, Hiroshi

    1987-03-01

    The author's work in the study on the leaching behavior of simulated high-level waste (HLW) glass were summarized. The subjects described are (1) leach rates at high temperatures, (2) effects of cracks on leach rates, (3) effects of flow rate on leach rates, and (4) an in-situ burial test in natural groundwater. In the following section, the leach rates obtained by various experiments were summarized and discussed. (author)

  20. Preparation of RF-(VM-SiO2n-RF/AM-Cellu Nanocomposites, and Use Thereof for the Modification of Glass and Filter Paper Surfaces: Creation of a Glass Thermoresponsive Switching Behavior and an Efficient Separation Paper Membrane

    Hideo Sawada

    2017-03-01

    Full Text Available Fluoroalkyl end-capped vinyltrimethoxysilane oligomeric silica/alkyl-modified cellulose (AM-Cellu nanocomposites [RF-(CH2-CHSiO2n-RF/AM-Cellu; n = 2, 3; RF = CF(CF3OC3F7] were prepared by the sol-gel reactions of the corresponding oligomer [RF-(CH2-CHSi(OMe3n-RF] in the presence of AM-Cellu. The nanocomposites thus obtained were applied to the surface modification of glass to exhibit a highly oleophobic/superhydrophilic characteristic on the modified surface at 20 °C. Interestingly, a temperature dependence of contact angle values of dodecane and water was observed on the modified surface at 20~70 °C, and the dodecane contact angle values were found to decrease with increasing the temperatures from 20 to 70 °C to provide from highly oleophobic to superoleophilic characteristics on the surface. On the other hand, the increase of the water contact angle values was observed with the increase in the temperatures under similar conditions to supply superhydrophilic to superhydrophobic characteristics on the modified surface. The corresponding nanocomposites were also applied to the surface modification of the filter paper under similar conditions to afford a superoleophilic/superhydrophobic characteristic on the surface. It was demonstrated that the modified filter paper is effective for the separation membrane for W/O emulsion to isolate the transparent colorless oil.

  1. Hanford enhanced waste glass characterization. Influence of composition on chemical durability

    Fox, K. M.; Edwards, T. B.

    2016-01-01

    This report provides a review of the complete high-level waste (HLW) and low-activity waste (LAW) data sets for the glasses recently fabricated at Pacific Northwest National Laboratory and characterized at Savannah River National Laboratory (SRNL). The review is from the perspective of relating the chemical durability performance to the compositions of these study glasses, since the characterization work at SRNL focused on chemical analysis and ASTM Product Consistency Test (PCT) performance.

  2. Preparation and microwave absorbing property of Ni–Zn ferrite-coated hollow glass microspheres with polythiophene

    Li, Lindong; Chen, Xingliang; Qi, Shuhua, E-mail: qishuhuanwpu@163.com

    2016-11-01

    The composite of hollow glass microspheres (HMG) coated by Ni{sub 0.7}Zn{sub 0.3}Fe{sub 2}O{sub 4} particles was fabricated via sol–gel method, and then the ternary composite (HMG/Ni{sub 0.7}Zn{sub 0.3}Fe{sub 2}O{sub 4}/PT) was synthesized by in situ polymerization. The electrical property, magnetic performance and reflection loss of the composites were measured, and the results suggest that the conductivity and the saturation magnetization (Ms) of HMG/Ni{sub 0.7}Zn{sub 0.3}Fe{sub 2}O{sub 4}/PT reach 6.87×10{sup −5} S/cm and 11.627 emu/g, respectively. The ternary composite has good microwave absorbing properties (R{sub min}=−13.79 dB at 10.51 GHz) and the bandwidth less than −10 dB can reach 2.6 GHz (from 9.4 to 12.0 GHz) in X band (8.2–12.4 GHz). The morphology and chemical structure of the samples were measured through scanning electron microscopy (SEM), X-Ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). This paper also analyzes the relationship between the reflection loss of the absorber and its thickness. - Highlights: • This manuscript synthesized HMG/Ni{sub 0.7}Zn{sub 0.3}Fe{sub 2}O{sub 4}/PT composites. • The surface morphology, electrical property, magnetic performance and reflection loss of the composites were measured. • This paper also analyzed the relationship between the reflection loss of the absorber and its thickness.

  3. Microstructure analysis of cofebsinb metallic glasses with a various geometry prepared by planar flow casting and suction casting methods

    Hosko, J.; Janotova, J.; Svec, P.; Matko, I.; Janickovic, D.; Svec, P. Sr.

    2012-01-01

    In this paper we have studied the structure of as-cast Co_4_7Fe_2_0_._9B_2_1_._2Si_4_._6Nb_6_._3 ribbon, bilayer and bulk samples in form of rods up to 5 mm diameter. Amorphous structure of the ribbons and bilayer prepared by PFC was confirmed by XRD characterization. XRD analysis of the bulk sample with 5 mm diameter indicated the presence of crystalline phases. However, XRD analysis of the bulk sample with 4 mm diameter indicated no significant crystalline peaks. From TEM analysis it was found that in-situ BMG composite was obtained in bulk sample. The edge of bulk sample with 4 mm diameter was fully amorphous, however, the center of this sample contains crystalline particles of micron sizes dispersed in the amorphous matrix. Our results suggest that the system Co_4_7Fe_2_0_._9B_2_1_._2Si_4_._6Nb_6_._3 has high GFA because we have prepared various amorphous materials with different shape and thickness using the techniques of suction casting, modified PFC and PFC. The critical diameter of bulk samples with chemical composition Co_4_7Fe_2_0_._9B_2_1_._2Si_4_._6Nb_6_._3 for emergence amorphous phase is 4 mm. (authors)

  4. Radiation effects in glass waste forms for high-level waste and plutonium disposal

    Weber, W.J.; Ewing, R.C.

    1997-01-01

    A key challenge in the permanent disposal of high-level waste (HLW), plutonium residues/scraps, and excess weapons plutonium in glass waste forms is the development of predictive models of long-term performance that are based on a sound scientific understanding of relevant phenomena. Radiation effects from β-decay and α-decay can impact the performance of glasses for HLW and Pu disposition through the interactions of the α-particles, β-particles, recoil nuclei, and γ-rays with the atoms in the glass. Recently, a scientific panel convened under the auspices of the DOE Council on Materials Science to assess the current state of understanding, identify important scientific issues, and recommend directions for research in the area of radiation effects in glasses for HLW and Pu disposition. The overall finding of the panel was that there is a critical lack of systematic understanding on radiation effects in glasses at the atomic, microscopic, and macroscopic levels. The current state of understanding on radiation effects in glass waste forms and critical scientific issues are presented

  5. Corrosion resistance of metal materials for HLW canister

    Furuya, Takashi; Muraoka, Susumu; Tashiro, Shingo

    1982-02-01

    In order to verify the materials as an important artificial barrier for canister of vitrified high-level waste from spent fuel reprocessing, data and reports were researched on corrosion resistance of the materials under conditions from glass form production to final disposal. Then, in this report, investigated subjects, improvement methods and future subjects are reviewed. It has become clear that there would be no problem on the inside and outside corrosion of the canister during glass production, but long term corrosion and radiation effect tests and the vitrification methods would be subjects in future on interim storage and final disposal conditions. (author)

  6. Characterization of Simulant LAW Envelope A, B, and C with Glass Formers

    Hansen, E.K.

    2000-01-01

    The River Protection Project-Waste Treatment Plant (RPP-WPT) pretreatment and immobilization processes being developed by the DOE Office of River Protection will decontaminate High Level Waste (HLW) Envelopes A and B supernates using crossflow filtration followed by cesium and technetium ion exchange. Envelope C will undergo Sr/TRU precipitation prior to filtration to remove chelated actinides. The decontaminated supernates, now called low activity waste (LAW), will be concentrated through the LAW Melter Feed Evaporator. The concentrated LAW Melter Feed will be mixed with glass forming minerals and chemicals in an in the LAW Melter Feed Preparation Tank. The resulting slurry is then transferred to a Melter Feed Tank from which it is fed to one of the joule-heated, refractory-lined melters. Characterization of the melter feed slurry is required to complete the design of the RPP-WPT slurry feed systems. This report discusses the results obtained from the task, ''Bench Scale Mixing - Characterization of Simulant LAW Envelope A (AN105), B (AZ101), and C (AN107) With Glass Formers''. This task characterized the physical and chemical properties (rheology, particle size, weight percent soluble and insoluble solids, and chemical composition) of simulated LAW Melter feeds made from the different envelopes mentioned above. The goal of this task was to provide data for the design of the RPP-WPT Melter feed system

  7. Novel waste forms for HLW and ILW immobilisation

    Lee, William E.; Milestone, Neil B.; Ojovan, Michael I.; Hyatt, Neil C.; Stennett, Martin C.; Setiadi, Anthony; Zhou, Qizhi

    2006-01-01

    The complex nature and heterogeneity of legacy wastes means that a toolbox of different host systems must be developed in which to immobilize them. New zirconolite ceramic, glass composite materials and novel cement systems including calcium sulpho aluminate cements and alkali activated slags being examined in the Immobilisation Science Laboratory at the University of Sheffield are described. (authors)

  8. Nucleation and crystal growth behavior of nepheline in simulated high-level waste glasses

    Fox, K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Amoroso, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Mcclane, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-09-26

    The Savannah River National Laboratory (SRNL) has been tasked with supporting glass formulation development and process control strategies in key technical areas, relevant to the Department of Energy’s Office of River Protection (DOE-ORP) and related to high-level waste (HLW) vitrification at the Waste Treatment and Immobilization Plant (WTP). Of specific interest is the development of predictive models for crystallization of nepheline (NaAlSiO4) in HLW glasses formulated at high alumina concentrations. This report summarizes recent progress by researchers at SRNL towards developing a predicative tool for quantifying nepheline crystallization in HLW glass canisters using laboratory experiments. In this work, differential scanning calorimetry (DSC) was used to obtain the temperature regions over which nucleation and growth of nepheline occur in three simulated HLW glasses - two glasses representative of WTP projections and one glass representative of the Defense Waste Processing Facility (DWPF) product. The DWPF glass, which has been studied previously, was chosen as a reference composition and for comparison purposes. Complementary quantitative X-ray diffraction (XRD) and optical microscopy confirmed the validity of the methodology to determine nucleation and growth behavior as a function of temperature. The nepheline crystallization growth region was determined to generally extend from ~ 500 to >850 °C, with the maximum growth rates occurring between 600 and 700 °C. For select WTP glass compositions (high Al2O3 and B2O3), the nucleation range extended from ~ 450 to 600 °C, with the maximum nucleation rates occurring at ~ 530 °C. For the DWPF glass composition, the nucleation range extended from ~ 450 to 750 °C with the maximum nucleation rate occurring at ~ 640 °C. The nepheline growth at the peak temperature, as determined by XRD, was between 35 - 75 wt.% /hour. A maximum nepheline growth rate of ~ 0.1 mm/hour at 700 °C was measured for the DWPF

  9. Nucleation and crystal growth behavior of nepheline in simulated high-level waste glasses

    Fox, K.; Amoroso, J.; Mcclane, D.

    2017-01-01

    The Savannah River National Laboratory (SRNL) has been tasked with supporting glass formulation development and process control strategies in key technical areas, relevant to the Department of Energy's Office of River Protection (DOE-ORP) and related to high-level waste (HLW) vitrification at the Waste Treatment and Immobilization Plant (WTP). Of specific interest is the development of predictive models for crystallization of nepheline (NaAlSiO4) in HLW glasses formulated at high alumina concentrations. This report summarizes recent progress by researchers at SRNL towards developing a predicative tool for quantifying nepheline crystallization in HLW glass canisters using laboratory experiments. In this work, differential scanning calorimetry (DSC) was used to obtain the temperature regions over which nucleation and growth of nepheline occur in three simulated HLW glasses - two glasses representative of WTP projections and one glass representative of the Defense Waste Processing Facility (DWPF) product. The DWPF glass, which has been studied previously, was chosen as a reference composition and for comparison purposes. Complementary quantitative X-ray diffraction (XRD) and optical microscopy confirmed the validity of the methodology to determine nucleation and growth behavior as a function of temperature. The nepheline crystallization growth region was determined to generally extend from ~ 500 to >850 °C, with the maximum growth rates occurring between 600 and 700 °C. For select WTP glass compositions (high Al2O3 and B2O3), the nucleation range extended from ~ 450 to 600 °C, with the maximum nucleation rates occurring at ~ 530 °C. For the DWPF glass composition, the nucleation range extended from ~ 450 to 750 °C with the maximum nucleation rate occurring at ~ 640 °C. The nepheline growth at the peak temperature, as determined by XRD, was between 35 - 75 wt.% /hour. A maximum nepheline growth rate of ~ 0.1 mm/hour at 700 °C was measured for the DWPF

  10. Corrosion testing of a plutonium-loaded lanthanide borosilicate glass made with Frit B.

    Ebert, W. L.; Chemical Engineering

    2006-09-30

    Laboratory tests were conducted with a lanthanide borosilicate (LaBS) glass made with Frit B and added PuO2 (the glass is referred to herein as Pu LaBS-B glass) to measure the dependence of the glass dissolution rate on pH and temperature. These results are compared with the dependencies used in the Defense HLW Glass Degradation Model that was developed to account for HLW glasses in total system performance assessment (TSPA) calculations for the Yucca Mountain repository to determine if that model can also be used to represent the release of radionuclides from disposed Pu LaBS glass by using either the same parameter values that are used for HLW glasses or parameter values specific for Pu LaBS glass. Tests were conducted by immersing monolithic specimens of Pu LaBS-B glass in six solutions that imposed pH values between about pH 3.5 and pH 11, and then measuring the amounts of glass components released into solution. Tests were conducted at 40, 70, and 90 C for 1, 2, 3, 4, and 5 days at low glass-surface-area-to-solution volume ratios. As intended, these test conditions maintained sufficiently dilute solutions that the impacts of solution feedback effects on the dissolution rates were negligible in most tests. The glass dissolution rates were determined from the concentrations of Si and B measured in the test solutions. The dissolution rates determined from the releases of Si and B were consistent with the 'V' shaped pH dependence that is commonly seen for borosilicate glasses and is included in the Defense HLW Glass Degradation Model. The rate equation in that model (using the coefficients determined for HLW glasses) provides values that are higher than the Pu LaBS-B glass dissolution rates that were measured over the range of pH and temperature values that were studied (i.e., an upper bound). Separate coefficients for the rate expression in acidic and alkaline solutions were also determined from the test results to model Pu LaBS-B glass dissolution

  11. Transmission photocathodes based on stainless steel mesh and quartz glass coated with N-doped DLC thin films prepared by reactive magnetron sputtering

    Balalykin, N. I.; Huran, J.; Nozdrin, M. A.; Feshchenko, A. A.; Kobzev, A. P.; Arbet, J.

    2016-03-01

    The influence was investigated of N-doped diamond-like carbon (DLC) films properties on the quantum efficiency of a prepared transmission photocathode. N-doped DLC thin films were deposited on a silicon substrate, a stainless steel mesh and quartz glass (coated with 5 nm thick Cr adhesion film) by reactive magnetron sputtering using a carbon target and gas mixture Ar, 90%N2+10%H2. The elements' concentration in the films was determined by RBS and ERD. The quantum efficiency was calculated from the measured laser energy and the measured cathode charge. For the study of the vectorial photoelectric effect, the quartz type photocathode was irradiated by intensive laser pulses to form pin-holes in the DLC film. The quantum efficiency (QE), calculated at a laser energy of 0.4 mJ, rose as the nitrogen concentration in the DLC films was increased and rose dramatically after the micron-size perforation in the quartz type photocathodes.

  12. Development of thermal analysis method for the near field of HLW repository using ABAQUS

    Kuh, Jung Eui; Kang, Chul Hyung; Park, Jeong Hwa [Korea Atomic Energy Research Institute, Taejon (Korea)

    1998-10-01

    An appropriate tool is needed to evaluate the thermo-mechanical stability of high level radioactive waste (HLW) repository. In this report a thermal analysis methodology for the near field of HLW repository is developed to use ABAQUS which is one of the multi purpose FEM code and has been used for many engineering area. The main contents of this methodology development are the structural and material modelling to simulate a repository, setup of side conditions, e.g., boundary and load conditions, and initial conditions, and the procedure to selection proper material parameters. In addition to these, the interface programs for effective production of input data and effective change of model size for sensitivity analysis for disposal concept development are developed. The results of this work will be apply to evaluate the thermal stability and to use as main input data for mechanical analysis of HLW repository. (author). 20 refs., 15 figs., 5 tabs.

  13. Applicability of thermodynamic database of radioactive elements developed for the Japanese performance assessment of HLW repository

    Yui, Mikazu; Shibata, Masahiro; Rai, Dhanpat; Ochs, Michael

    2003-01-01

    In 1999 Japan Nuclear Cycle Development Institute (JNC) published a second progress report (also known as H12 report) on high-level radioactive waste (HLW) disposal in Japan (JNC 1999). This report helped to develop confidence in the selected HLW disposal system and to establish the implementation body in 2000 for the disposal of HLW. JNC developed an in-house thermodynamic database for radioactive elements for performance analysis of the engineered barrier system (EBS) and the geosphere for H12 report. This paper briefly presents the status of the JNC's thermodynamic database and its applicability to perform realistic analyses of the solubilities of radioactive elements, evolution of solubility-limiting solid phases, predictions of the redox state of Pu in the neutral pH range under reducing conditions, and to estimate solubilities of radioactive elements in cementitious conditions. (author)

  14. The Results of HLW Processing Using Zirconium Salt of Dibutyl phosphoric Acid in Hot Cell

    Fedorov, Yu.S.; Zilberman, B.Ya.; Shmidt, O.V. [Khlopin Radium Institute, 2nd Murinsky Ave., 28, Saint-Petersburg, 194021 (Russian Federation)

    2008-07-01

    Zirconium salt of dibutyl phosphoric acid (ZS HDBP), is an effective solvent for liquid HLW and ILW (high and intermediate level wastes) processing with radionuclide partitioning into different groups for further immobilization according to radiotoxicity. The rig trials in mixer-settles in hot cells were carried out using 30 L of real HLW containing transplutonium (TPE), rare earths (RE), Sr and Cs in 2 mol/L HNO{sub 3}, characterized by total specific activity 520 MBk/L. The recovery factor for TPE and RE was as high as 10{sup 4}, but only 10 for Sr. Purification factor of TPE and RE from Cs and Sr was 10{sup 4}, and that of Sr from TPE and Cs was 10{sup 3}. Almost all Cs was localized in the second cycle raffinate. So Zr salt of HDBP can be used in HLW processing with radionuclide partitioning with respect to the categories of radiotoxicity. (authors)

  15. Regulatory status on the safety assessment of a HLW repository in other countries

    Lee, Sung Ho; Hwang, Yong Soo

    2008-12-01

    To construct a HLW repository, it is essential to meet the requirements on the regulation for a deep geological disposal. Even if the construction of a HLW repository is determined positively, technical standards which assert the performance of a repository will be needed. Among various technical standards, safety assessment based on the repository evolution in the future will play an important role in the licensing process. The foreign countries' technical standards on the safety assessment of a HLW repository may be an indicator to carry out the R and D activities on geological disposal effectively. In this report, assessment period, limit of radiation dose and uncertainty related to the safety assessment are investigated and analyzed in detail. Especially, the technical reviews of USA regulation bodies seems to be reasonable in the point of the intrinsic attribute of safety assessment

  16. Study on evaluation method for potential effect of natural phenomena on a HLW disposal system

    Kawamura, Makoto; Makino, Hitoshi; Umeda, Koji; Osawa, Hideaki; Seo, Toshihiro; Ishimaru, Tsuneaki

    2005-01-01

    Evaluation for the potential effect of natural phenomena on a HLW disposal system is an important issue in safety assessment. A scenario construction method for the effects on a HLW disposal system condition and performance has been developed for two purposes: the first being effective elicitation and organization of information from investigators of natural phenomena and performance assessor and the second being, maintenance of traceability of scenario construction processes with suitable records. In this method, a series of works to construct scenarios is divided into pieces to facilitate and to elicit the features of potential effect of natural phenomena on a HLW disposal system and is organized to create reasonable scenarios with consistency, traceability and adequate conservativeness within realistic view. (author)

  17. Cold-Crucible Design Parameters for Next Generation HLW Melters

    Gombert, D.; Richardson, J.; Aloy, A.; Day, D.

    2002-01-01

    The cold-crucible induction melter (CCIM) design eliminates many materials and operating constraints inherent in joule-heated melter (JHM) technology, which is the standard for vitrification of high-activity wastes worldwide. The cold-crucible design is smaller, less expensive, and generates much less waste for ultimate disposal. It should also allow a much more flexible operating envelope, which will be crucial if the heterogeneous wastes at the DOE reprocessing sites are to be vitrified. A joule-heated melter operates by passing current between water-cooled electrodes through a molten pool in a refractory-lined chamber. This design is inherently limited by susceptibility of materials to corrosion and melting. In addition, redox conditions and free metal content have exacerbated materials problems or lead to electrical short-circuiting causing failures in DOE melters. In contrast, the CCIM design is based on inductive coupling of a water-cooled high-frequency electrical coil with the glass, causing eddycurrents that produce heat and mixing. A critical difference is that inductance coupling transfers energy through a nonconductive solid layer of slag coating the metal container inside the coil, whereas the jouleheated design relies on passing current through conductive molten glass in direct contact with the metal electrodes and ceramic refractories. The frozen slag in the CCIM design protects the containment and eliminates the need for refractory, while the corrosive molten glass can be the limiting factor in the JH melter design. The CCIM design also eliminates the need for electrodes that typically limit operating temperature to below 1200 degrees C. While significant marketing claims have been made by French and Russian technology suppliers and developers, little data is available for engineering and economic evaluation of the technology, and no facilities are available in the US to support testing. A currently funded project at the Idaho National Engineering

  18. Modelling spent fuel and HLW behaviour in repository conditions

    Esparza, A M; Esteban, J A

    2003-07-01

    The aim of this report is to give the reader an overall insight of the different models, which are used to predict the long-term behaviour of the spent fuels and HLW disposed in a repository. The models must be established on basic data and robust kinetics describing the mechanisms controlling spent fuel alteration/dissolution in a repository. The UO2 matrix, or source term, contains embedded in it the , majority of radionuclides of the spent fuel (some are in the gap cladding). For this reason the SF radionuclides release models play a significant role in the performance assessment of radioactive waste disposal. The differences existing between models published in the literature are due to the conceptual understanding of the processes and the degree of the conservatism used with the parameter values, and the boundary conditions. They mainly differ in their level of simplification and their final objective. Sometimes are focused the show compliance with regulatory requirements, other to support decision making, to increase the level of confidence of public and scientific community, could be empirical, semi-empirical or analytical. The models take into account the experimental results from radionuclides releases and their extrapolation to the very long term. Its necessary a great statistics for have a representative dissolution rate, due at the number of experimental results is not very high and many of them show a great scatter, independently of theirs different compositions by axial and radial variations, due to linear power or local burnup. On the other hand, it is difficult to predict the spent fuel behaviour over the long term, based in short term experiments. In this report is given a little description of the radionuclides distribution in the spent fuel and also in the cladding/pellet gap, grain boundary, cracks and rim zones (the matrix rim zone can be considered with an especial characteristics very different to the rest of the spent fuel), and structural

  19. Modelling spent fuel and HLW behaviour in repository conditions

    Esparza, A. M.; Esteban, J. A.

    2003-01-01

    The aim of this report is to give the reader an overall insight of the different models, which are used to predict the long-term behaviour of the spent fuels and HLW disposed in a repository. The models must be established on basic data and robust kinetics describing the mechanisms controlling spent fuel alteration/dissolution in a repository. The UO2 matrix, or source term, contains embedded in it the , majority of radionuclides of the spent fuel (some are in the gap cladding). For this reason the SF radionuclides release models play a significant role in the performance assessment of radioactive waste disposal. The differences existing between models published in the literature are due to the conceptual understanding of the processes and the degree of the conservatism used with the parameter values, and the boundary conditions. They mainly differ in their level of simplification and their final objective. Sometimes are focused the show compliance with regulatory requirements, other to support decision making, to increase the level of confidence of public and scientific community, could be empirical, semi-empirical or analytical. The models take into account the experimental results from radionuclides releases and their extrapolation to the very long term. Its necessary a great statistics for have a representative dissolution rate, due at the number of experimental results is not very high and many of them show a great scatter, independently of theirs different compositions by axial and radial variations, due to linear power or local burnup. On the other hand, it is difficult to predict the spent fuel behaviour over the long term, based in short term experiments. In this report is given a little description of the radionuclides distribution in the spent fuel and also in the cladding/pellet gap, grain boundary, cracks and rim zones (the matrix rim zone can be considered with an especial characteristics very different to the rest of the spent fuel), and structural

  20. Cesium and strontium fractionation from HLW for thermal-stress reduction in a geologic repository

    McKee, R.W.

    1983-02-01

    Results are described for a study to assess the benefits and costs of fractionating the cesium and strontium components in commercial high-level waste (HLW) to a separate waste stream for the purpose of reducing geologic repository thermal stresses. System costs are developed for a broad range of conditions comparing the Cs/Sr fractionation concept with disposal of 10-year old vitrified HLW and vitrified HLW aged to achieve (through decay) the same heat output as the fractionated high-level waste (FHLW). All comparisons are based on a 50,000 metric ton equivalent (MTE) system. The FHLW and the Cs/Sr waste are both disposed of a vitrified waste but emplaced in separate areas of a basalt repository. The FHLW is emplaced in high-integrity packages at relatively high waste loading but low heat loading, while the Cs/Sr waste is emplaced in minimum integrity packages at relatively high heat loading. System cost comparisons are based on minimum cost combinations of canister diameter, waste concentration, and canister spacing in a basalt repository for each waste type. The effects on both long- and near-term safety considerations are also addressed. The major conclusion is that the Cs/Sr fractionation concept offers, potentially, a substantial total system cost advantage for HLW disposal if reduced HLW package temperatures in a basalt repository are desired. However, there is no cost advantage if currently designated maximum design temperatures are acceptable. Aging the HLW for 50 to 100 years can accomplish similar results at equivalent or loser costs

  1. Glass sealing

    Brow, R.K.; Kovacic, L.; Chambers, R.S. [Sandia National Labs., Albuquerque, NM (United States)

    1996-04-01

    Hernetic glass sealing technologies developed for weapons component applications can be utilized for the design and manufacture of fuel cells. Design and processing of of a seal are optimized through an integrated approach based on glass composition research, finite element analysis, and sealing process definition. Glass sealing procedures are selected to accommodate the limits imposed by glass composition and predicted calculations.

  2. Minor component study for simulated high-level nuclear waste glasses (Draft)

    Li, H.; Langowskim, M.H.; Hrma, P.R.; Schweiger, M.J.; Vienna, J.D.; Smith, D.E.

    1996-02-01

    Hanford Site single-shell tank (SSI) and double-shell tank (DSI) wastes are planned to be separated into low activity (or low-level waste, LLW) and high activity (or high-level waste, HLW) fractions, and to be vitrified for disposal. Formulation of HLW glass must comply with glass processibility and durability requirements, including constraints on melt viscosity, electrical conductivity, liquidus temperature, tendency for phase segregation on the molten glass surface, and chemical durability of the final waste form. A wide variety of HLW compositions are expected to be vitrified. In addition these wastes will likely vary in composition from current estimates. High concentrations of certain troublesome components, such as sulfate, phosphate, and chrome, raise concerns about their potential hinderance to the waste vitrification process. For example, phosphate segregation in the cold cap (the layer of feed on top of the glass melt) in a Joule-heated melter may inhibit the melting process (Bunnell, 1988). This has been reported during a pilot-scale ceramic melter run, PSCM-19, (Perez, 1985). Molten salt segregation of either sulfate or chromate is also hazardous to the waste vitrification process. Excessive (Cr, Fe, Mn, Ni) spinel crystal formation in molten glass can also be detrimental to melter operation

  3. Processes for consensus building and role sharing. Lessons learned from HLW policies in European countries

    Nagano, Koji

    2003-01-01

    This report attempts to obtain lessons in implementation of HLW management policies for Japan by reviewing past experiences and present status of policy formulation and implementation as well as reflection of public opinions and consensus building of selected European countries, such as Finland, Sweden and others. After examining the situations of those countries, the author derives four key aspects that need to be addressed; separation of nuclear energy policies and HLW policies, fundamental support shared among national public, sense of controllability, and proper scheme of responsibility sharing. (author)

  4. Perspective: Highly stable vapor-deposited glasses

    Ediger, M. D.

    2017-12-01

    This article describes recent progress in understanding highly stable glasses prepared by physical vapor deposition and provides perspective on further research directions for the field. For a given molecule, vapor-deposited glasses can have higher density and lower enthalpy than any glass that can be prepared by the more traditional route of cooling a liquid, and such glasses also exhibit greatly enhanced kinetic stability. Because vapor-deposited glasses can approach the bottom of the amorphous part of the potential energy landscape, they provide insights into the properties expected for the "ideal glass." Connections between vapor-deposited glasses, liquid-cooled glasses, and deeply supercooled liquids are explored. The generality of stable glass formation for organic molecules is discussed along with the prospects for stable glasses of other types of materials.

  5. Production of lightweight foam glass (invited talk)

    Petersen, Rasmus Rosenlund; König, Jakob; Yue, Yuanzheng

    The foam glass production allows low cost recycling of postconsumer glass and industrial waste materials as foaming agent or as melt resource. Foam glass is commonly produced by utilising milled glass mixed with a foaming agent. The powder mixture is heat-treated to around 10^3.7 – 10^6 Pa s, which...... result in viscous sintering and subsequent foaming of the glass melt. The porous glass melt is cooled down to room temperature to freeze-in the foam structure. The resulting foam glass is applied in constructions as a light weight material to reduce load bearing capacity and as heat insulating material...... in buildings and industry. We foam panel glass from old televisions with different foaming agents. We discuss the foaming ability and the foaming mechanism of different foaming systems. We compare several studies to define a viscous window for preparing low density foam glass. However, preparing foam glass...

  6. Oxynitride glasses: a review

    Garcia, A.R.; Clausell, C.; Barba, A.

    2016-07-01

    Oxynitride glasses are special types of silicates or silicoaluminates which have been the object of many studies over the last forty years. They can be prepared by means of various complex methods, leading to variable levels of nitrogen incorporation, though in all cases giving limited transparency in the visible range. More recently, a new family of oxynitride glasses incorporating fluorine has been investigated. This paper outlines the effect of composition, in particular nitrogen and fluorine content, on properties such as glass transition temperature, hardness, Young's modulus, compactness and molar volume. (Author)

  7. Crystallization of Yttrium and Samarium Aluminosilicate Glasses

    Lago, Diana Carolina; Prado, Miguel Oscar

    2016-01-01

    Aluminosilicate glasses containing samarium and yttrium (SmAS and YAS glasses) exhibit high glass transition temperatures, corrosion resistance, and glass stability on heating which make them useful for technological applications. Yttrium aluminosilicate glass microspheres are currently being used for internal selective radiotherapy of liver cancer. During the preparation process, crystallization needs to be totally or partially avoided depending on the final application. Thus knowing the cry...

  8. Preparation and properties of Li2O-BaO-Al2O3 -SiO2 glass-ceramic materials

    Gamal A. Khater

    2014-12-01

    Full Text Available The crystallization of some glasses, based on celsian-spodumene glass-ceramics, was investigated by different techniques including differential thermal analysis, optical microscope, X-ray diffraction, indentation, microhardness, bending strengths, water absorption and density measurement. The batches were melted and then cast into glasses, which were subjected to heat treatment to induce controlled crystallization. The resulting crystalline materials were mainly composed of β-eucryptite solid solution, β-spodumene solid solution, hexacelsian and monoclinic celsian, exhibiting fine grains and uniform texture. It has been found that an increasing content of celsian phase in the glasses results in increased bulk crystallization. The obtained glass-ceramic materials are characterized by high values of hardness ranging between 953 and 1013 kg/mm2, zero water absorption and bending strengths values ranging between 88 and 126 MPa, which makes them suitable for many applications under aggressive mechanical conditions.

  9. Colloid formation during waste glass corrosion

    Mertz, C.J.; Buck, E.C.; Fortner, J.A.; Bates, J.K.

    1996-01-01

    The long-term behavior of nuclear waste glass in a geologic repository may require a technical consideration of the role of colloids in the release and transport of radionuclides. The neglect of colloidal properties in assessing the near- and far-field migration behavior of actinides may lead to significant underestimates and poor predictions of biosphere exposure from high-level waste (HLW) disposal. Existing data on colloid-facilitated transport suggests that radionuclide migration may be enhanced, but the importance of colloids is not adequately assessed. Indeed, the occurrence of radionuclide transport, attributed to colloidal species, has been reported at Mortandad Canyon, Los Alamos and at the Nevada Test Site; both unsaturated regions are similar to the proposed HLW repository at Yucca Mountain. Although some developments have been made on understanding the transport characteristics of colloids, the characterization of colloids generated from the corrosion of the waste form has been limited. Colloids are known to incorporate radionuclides either from hydrolysis of dissolved species (real colloids) or from adsorption of dissolved species onto existing groundwater colloids (pseudocolloids); however, these colloids may be considered secondary and solubility limited when compared to the colloids generated during glass alteration

  10. Key Factors to Determine the Borehole Spacing in a Deep Borehole Disposal for HLW

    Lee, Jongyoul; Choi, Heuijoo; Lee, Minsoo; Kim, Geonyoung; Kim, Kyeongsoo

    2015-01-01

    Deep fluids also resist vertical movement because they are density stratified and reducing conditions will sharply limit solubility of most dose critical radionuclides at the depth. Finally, high ionic strengths of deep fluids will prevent colloidal transport. Therefore, as an alternative disposal concept, i.e., deep borehole disposal technology is under consideration in number of countries in terms of its outstanding safety and cost effectiveness. In this paper, the general concept for deep borehole disposal of spent fuels or high level radioactive wastes which has been developed by some countries according to the rapid advance in the development of drilling technology, as an alternative method to the deep geological disposal method, was reviewed. After then an analysis on key factors for the distance between boreholes for the disposal of HLW was carried out. In this paper, the general concept for deep borehole disposal of spent fuels or HLW wastes, as an alternative method to the deep geological disposal method, were reviewed. After then an analysis on key factors for the determining the distance between boreholes for the disposal of HLW was carried out. These results can be used for the development of the HLW deep borehole disposal system

  11. Key Factors to Determine the Borehole Spacing in a Deep Borehole Disposal for HLW

    Lee, Jongyoul; Choi, Heuijoo; Lee, Minsoo; Kim, Geonyoung; Kim, Kyeongsoo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Deep fluids also resist vertical movement because they are density stratified and reducing conditions will sharply limit solubility of most dose critical radionuclides at the depth. Finally, high ionic strengths of deep fluids will prevent colloidal transport. Therefore, as an alternative disposal concept, i.e., deep borehole disposal technology is under consideration in number of countries in terms of its outstanding safety and cost effectiveness. In this paper, the general concept for deep borehole disposal of spent fuels or high level radioactive wastes which has been developed by some countries according to the rapid advance in the development of drilling technology, as an alternative method to the deep geological disposal method, was reviewed. After then an analysis on key factors for the distance between boreholes for the disposal of HLW was carried out. In this paper, the general concept for deep borehole disposal of spent fuels or HLW wastes, as an alternative method to the deep geological disposal method, were reviewed. After then an analysis on key factors for the determining the distance between boreholes for the disposal of HLW was carried out. These results can be used for the development of the HLW deep borehole disposal system.

  12. A GoldSim Based Biosphere Assessment Model for a HLW Repository

    Lee, Youn-Myoung; Hwang, Yong-Soo; Kang, Chul-Hyung

    2007-01-01

    To demonstrate the performance of a repository, the dose exposure to a human being due to nuclide releases from a repository should be evaluated and the results compared to the dose limit presented by the regulatory bodies. To evaluate a dose rate to an individual due to a long-term release of nuclides from a HLW repository, biosphere assessment models and their implemented codes such as ACBIO1 and ACBIO2 have been developed with the aid of AMBER during the last few years. BIOMASS methodology has been adopted for a HLW repository currently being considered in Korea, which has a similar concept to the Swedish KBS-3 HLW repository. Recently, not just only for verifying the purpose for biosphere assessment models but also for varying the possible alternatives to assess the consequences in a biosphere due to a HLW repository, another version of the assessment modesl has been newly developed in the frame of development programs for a total system performance assessment modeling tool by utilizing GoldSim. Through a current study, GoldSim approach for a biosphere modeling is introduced. Unlike AMBER by which a compartment scheme can be rather simply constructed with an appropriate transition rate between compartments, GoldSim was designed to facilitate the object-oriented modules by which specific models can be addressed in an additional manner, like solving jig saw puzzles

  13. Design options for HLW repository operation technology. (4) Shotclay technique for seamless construction of EBS

    Kobayashi, Ichizo; Fujisawa, Soh; Nakajima, Makoto; Toida, Masaru; Nakashima, Hitoshi; Asano, Hidekazu

    2011-01-01

    The shotclay method is construction method of the high density bentonite engineered barrier by spraying method. Using this method, the dry density of 1.6 Mg/m 3 , which was considered impossible with the spray method, is achieved. In this study, the applicability of the shotclay method to HLW bentonite-engineered barriers was confirmed experimentally. In the tests, an actual scale vertical-type HLW bentonite-engineered barrier was constructed. This was a bentonite-engineered barrier with a diameter of 2.22 m and a height of 3.13 m. The material used was bentonite with 30% silica sand, and water content was adjusted by mixing chilled bentonite with powdered ice before thawing. Work progress was 11.2 m 3 and the weight was 21.7 Mg. The dry density of the entire buffer was 1.62 Mg/m 3 , and construction time was approximately 8 hours per unit. After the formworks were removed, the core and block of the actual scale HLW bentonite-engineered barrier were sampled to confirm homogeneity. As a result, homogeneity was confirmed, and no gaps were observed between the formwork and the buffer material and between the simulated waste and the buffer material. The applicability to HLW of the shotclay method has been confirmed through this examination. (author)

  14. Disposal of defense spent fuel and HLW from the Idaho Chemical Processing Plant

    Ermold, L.F.; Loo, H.H.; Klingler, R.D.; Herzog, J.D.; Knecht, D.A.

    1992-12-01

    Acid high-level radioactive waste (HLW) resulting from fuel reprocessing at the Idaho Chemical Processing Plant (ICPP) for the US Department of Energy (DOE) has been solidified to a calcine since 1963 and stored in stainless steel bins enclosed by concrete vaults. Several different types of unprocessed irradiated DOE-owned fuels are also in storage ate the ICPP. In April, 1992, DOE announced that spent fuel would no longer be reprocessed to recover enriched uranium and called for a shutdown of the reprocessing facilities at the ICPP. A new Spent Fuel and HLW Technology Development program was subsequently initiated to develop technologies for immobilizing ICPP spent fuels and HLW for disposal, in accordance with the Nuclear Waste Policy Act. The Program elements include Systems Analysis, Graphite Fuel Disposal, Other Spent Fuel Disposal, Sodium-Bearing Liquid Waste Processing, Calcine Immobilization, and Metal Recycle/Waste Minimization. This paper presents an overview of the ICPP radioactive wastes and current spent fuels, with an emphasis on the description of HLW and spent fuels requiring repository disposal

  15. HLW Salt Disposition Alternatives Identification Preconceptual Phase I Summary Report (Including Attachments)

    Piccolo, S.F.

    1999-01-01

    The purpose of this report is to summarize the process used by the Team to systematically develop alternative methods or technologies for final disposition of HLW salt. Additionally, this report summarizes the process utilized to reduce the total list of identified alternatives to an ''initial list'' for further evaluation. This report constitutes completion of the team charter major milestone Phase I Deliverable

  16. Low phonon energies and wideband optical windows of La2O3-Ga2O3 glasses prepared using an aerodynamic levitation technique.

    Yoshimoto, Kohei; Masuno, Atsunobu; Ueda, Motoi; Inoue, Hiroyuki; Yamamoto, Hiroshi; Kawashima, Tastunori

    2017-03-30

    xLa 2 O 3 -(100 - x)Ga 2 O 3 binary glasses were synthesized by an aerodynamic levitation technique. The glass-forming region was found to be 20 ≤ x ≤ 57. The refractive indices were greater than 1.92 and increased linearly with increasing x. The polarizabilities of oxide ions were estimated to be 2.16-2.41 Å 3 , indicating that the glasses were highly ionic. The glasses were transparent over a very wide range from the ultraviolet to the mid-infrared region. The widest transparent window among the oxide glasses was from 270 nm to 10 μm at x = 55. From the Raman scattering spectra, a decrease in bridging oxide ions and an increase in non-bridging oxide ions were confirmed to occur with increasing La 2 O 3 content. The maximum phonon energy was found to be approximately 650 cm -1 , being one of the lowest among oxide glasses. These results show that La 2 O 3 -Ga 2 O 3 binary glasses should be promising host materials for optical applications such as lenses, windows, and filters over a very wide wavelength range.

  17. Low phonon energies and wideband optical windows of La2O3-Ga2O3 glasses prepared using an aerodynamic levitation technique

    Yoshimoto, Kohei; Masuno, Atsunobu; Ueda, Motoi; Inoue, Hiroyuki; Yamamoto, Hiroshi; Kawashima, Tastunori

    2017-03-01

    xLa2O3-(100 - x)Ga2O3 binary glasses were synthesized by an aerodynamic levitation technique. The glass-forming region was found to be 20 ≤ x ≤ 57. The refractive indices were greater than 1.92 and increased linearly with increasing x. The polarizabilities of oxide ions were estimated to be 2.16-2.41 Å3, indicating that the glasses were highly ionic. The glasses were transparent over a very wide range from the ultraviolet to the mid-infrared region. The widest transparent window among the oxide glasses was from 270 nm to 10 μm at x = 55. From the Raman scattering spectra, a decrease in bridging oxide ions and an increase in non-bridging oxide ions were confirmed to occur with increasing La2O3 content. The maximum phonon energy was found to be approximately 650 cm-1, being one of the lowest among oxide glasses. These results show that La2O3-Ga2O3 binary glasses should be promising host materials for optical applications such as lenses, windows, and filters over a very wide wavelength range.

  18. Influence of annealing temperature on the nanostructure TiO2-SnO2 prepared by electron gun method on the glass substrate and the aluminum/glass

    N Beigmohammadi

    2013-09-01

    Full Text Available  TiO2-SnO2 thin films were coated on glass and Al / glass substrates by electron gun method. In coating process, the vacuum was 1.5×10-5 torr. Then, films were annealed at 450, 500 and 550 ˚ C. The crystallographic structure and film morphology were investigated by means of XRD and SEM. The electrical (I-V and optical properties were studied by the two point props system and UV/Vis/NIR spectrophotometer. The results showed the films under 550 ˚ C were crystalline. The thickness and grain size were 350 and 50 nm respectively. The electrical conductivity in the sample with Al / glass substrate under 550 ˚ C was better than the other samples. When temperature increased, the energy gap decreased from 4.05 to 4.03 eV for direct cases.

  19. Influence of composition and preparation conditions on some physical properties of TeO2–Sb2O3–PbCl2 glasses

    Bošák, O.; Kostka, Petr; Minárik, S.; Trnovcová, V.; Podolinčiaková, J.; Zavadil, Jiří

    2013-01-01

    Roč. 377, spec. is. (2013), s. 74-78 ISSN 0022-3093. [International Symposium on Non-Oxide and New Optical Glasses /18./ - ISNOG 2012. Saint-Malo, 01.07.2012-05.07.2012] R&D Projects: GA ČR GAP106/12/2384; GA MŠk 7AMB12SK147 Institutional support: RVO:67985891 ; RVO:67985882 Keywords : heavy metal oxychloride glasses * TeO2 * electrical conductivity * static permittivity Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass; JA - Electronics ; Optoelectronics, Electrical Engineering (URE-Y) Impact factor: 1.716, year: 2013

  20. Natural glass analogues to alteration of nuclear waste glass: A review and recommendations for further study

    McKenzie, W.F.

    1990-01-01

    The purpose of this report is to review previous work on the weathering of natural glasses; and to make recommendations for further work with respect to studying the alteration of natural glasses as it relates quantifying rates of dissolution. the first task was greatly simplified by the published papers of Jercinovic and Ewing (1987) and Byers, Jercinovic, and Ewing (1987). The second task is obviously the more difficult of the two and the author makes no claim of completeness in this regard. Glasses weather in the natural environment by reacting with aqueous solutions producing a rind of secondary solid phases. It had been proposed by some workers that the thickness of this rind is a function of the age of the glass and thus could be used to estimate glass dissolution rates. However, Jercinovic and Ewing (1987) point out that in general the rind thickness does not correlate with the age of the glass owing to the differences in time of contact with the solution compared to the actual age of the sample. It should be noted that the rate of glass dissolution is also a function of the composition of both the glass and the solution, and the temperature. Quantification of the effects of these parameters (as well as time of contact with the aqueous phase and flow rates) would thus permit a prediction of the consequences of glass-fluid interactions under varying environmental conditions. Defense high- level nuclear waste (DHLW), consisting primarily of liquid and sludge, will be encapsulated by and dispersed in a borosilicate glass before permanent storage in a HLW repository. This glass containing the DHLW serves to dilute the radionuclides and to retard their dispersion into the environment. 318 refs

  1. Natural glass analogues to alteration of nuclear waste glass: A review and recommendations for further study

    McKenzie, W.F.

    1990-01-01

    The purpose of this report is to review previous work on the weathering of natural glasses; and to make recommendations for further work with respect to studying the alteration of natural glasses as it relates quantifying rates of dissolution. the first task was greatly simplified by the published papers of Jercinovic and Ewing (1987) and Byers, Jercinovic, and Ewing (1987). The second task is obviously the more difficult of the two and the author makes no claim of completeness in this regard. Glasses weather in the natural environment by reacting with aqueous solutions producing a rind of secondary solid phases. It had been proposed by some workers that the thickness of this rind is a function of the age of the glass and thus could be used to estimate glass dissolution rates. However, Jercinovic and Ewing (1987) point out that in general the rind thickness does not correlate with the age of the glass owing to the differences in time of contact with the solution compared to the actual age of the sample. It should be noted that the rate of glass dissolution is also a function of the composition of both the glass and the solution, and the temperature. Quantification of the effects of these parameters (as well as time of contact with the aqueous phase and flow rates) would thus permit a prediction of the consequences of glass-fluid interactions under varying environmental conditions. Defense high- level nuclear waste (DHLW), consisting primarily of liquid and sludge, will be encapsulated by and dispersed in a borosilicate glass before permanent storage in a HLW repository. This glass containing the DHLW serves to dilute the radionuclides and to retard their dispersion into the environment. 318 refs.

  2. Radiation effects on transport and bubble formation in silicate glasses. 1998 annual progress report

    Trifunac, A.D.

    1998-01-01

    'To study the fundamental chemistry of radiation damage in silicate/borosilicate glasses and simulated high-level nuclear waste (HLW) forms. Special emphasis is on delineating molecular processes crucial for understanding the aggregation of defects and formation of oxygen bubbles. The knowledge obtained will provide the needed scientific basis for extrapolating long-term behavior of stored radiative waste glass forms. This report summarizes the first 6 months of a 3-year project. The following issues have been addressed: (i) the production of radiolytic oxygen, (ii) the chemistry of hydrogenous species, and (iii) the effect of glass composition and microstructure on the formation and accumulation of metastable point defects.'

  3. Electronic structure of metallic glasses

    Oelhafen, P.; Lapka, R.; Gubler, U.; Krieg, J.; DasGupta, A.; Guentherodt, H.J.; Mizoguchi, T.; Hague, C.; Kuebler, J.; Nagel, S.R.

    1981-01-01

    This paper is organized in six sections and deals with (1) the glassy transition metal alloys, their d-band structure, the d-band shifts on alloying and their relation to the alloy heat of formation (ΔH) and the glass forming ability, (2) the glass to crystal phase transition viewed by valence band spectroscopy, (3) band structure calculations, (4) metallic glasses prepared by laser glazing, (5) glassy normal metal alloys, and (6) glassy hydrides

  4. Glass consistency and glass performance

    Plodinec, M.J.; Ramsey, W.G.

    1994-01-01

    Glass produced by the Defense Waste Processing Facility (DWPF) will have to consistently be more durable than a benchmark glass (evaluated using a short-term leach test), with high confidence. The DWPF has developed a Glass Product Control Program to comply with this specification. However, it is not clear what relevance product consistency has on long-term glass performance. In this report, the authors show that DWPF glass, produced in compliance with this specification, can be expected to effectively limit the release of soluble radionuclides to natural environments. However, the release of insoluble radionuclides to the environment will be limited by their solubility, and not glass durability

  5. Performance of surrogate high-level waste glass in the presence of iron corrosion products

    Jain, V.; Pan, Y.M.

    2004-01-01

    Radionuclide release from a waste package (WP) is a series of processes that depend upon the composition and flux of groundwater contacting the waste-forms (WF); the corrosion rate of WP containers and internal components made of Alloy 22, 316L SS, 304L SS and carbon steel; the dissolution rate of high-level radioactive waste (HLW) glass and spent nuclear fuel (SNF); the solubility of radionuclides; and the retention of radionuclides in secondary mineral phases. In this study, forward reaction rate measurements were made on a surrogate HLW glass in the presence of FeCl 3 species. Results indicate that the forward reaction rate increases with an increase in the FeCl 3 concentration. The addition of FeCl 3 causes the drop in the pH due to hydrolysis of Fe 3+ ions in the solution. Results based on the radionuclide concentrations and dissolution rates for HLW glass and SNF indicate that the contribution from glass is similar to SNF at 75 deg C. (authors)

  6. Preparation and optical characterization of PbCl(2)-Sb(2)O(3)-TeO(2) glasses doped with rare earth elements

    Kostka, Petr; Zavadil, Jiří; Pedlíková, Jitka; Poulain, M.

    2011-01-01

    Roč. 208, č. 8 (2011), s. 1821-1826 ISSN 1862-6300 R&D Projects: GA ČR GA104/08/0734 Institutional research plan: CEZ:AV0Z40320502; CEZ:AV0Z20670512 Keywords : glass * heavy metal oxides * optical properties * photoluminescence Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass Impact factor: 1.463, year: 2011

  7. Preparation and optical properties of TeO2-BaO-ZnO-ZnF2 fluoro-tellurite glass for mid-infrared fiber Raman laser applications

    Li, Jie; Xiao, Xusheng; Gu, Shaoxuan; Xu, Yantao; Zhou, Zhiguang; Guo, Haitao

    2017-04-01

    A serial of novel fluoro-tellurite glasses with compositions of 60TeO2-20BaO-(20-x)ZnO-xZnF2 (x = 0, 2, 4, 5 and 6 mol%) were prepared. The compositional dependences of glass structural evaluation, Raman gain coefficient, UV-Vis transmission spectrum, IR transmission spectrum, linear refractive index and third-order nonlinearity were analyzed. The results showed that the addition of 6 mol% ZnF2 can further improve the Raman gain coefficient to as well as 52 × 10-11 cm/W and effectively decrease around 73% and 57% absorption coefficients respectively caused by free Osbnd H groups (@3.3 μm) and hydrogen-bonded Osbnd H groups (@4.5 μm) in glass. Addition of ZnF2 does not change the UV-Vis absorption edge, optical band gap energy and infrared region cut-off edge almost, while the linear refraction index and ultrafast third-nonlinearity show unmonotonic changes. These novel fluoro-tellurite glasses may be suitable candidates for using in mid-infrared Raman fiber laser and/or amplifier.

  8. Colloidal glasses

    First page Back Continue Last page Overview Graphics. Colloidal glasses. Glassy state is attained when system fails to reach equilibrium due to crowding of constituent particles. In molecular glasses, glassy state is reached by rapidly lowering the temperature. In colloidal glasses, glassy state is reached by increasing the ...

  9. Glass containing radioactive nuclear waste

    Boatner, L.A.; Sales, B.C.

    1985-01-01

    Lead-iron phosphate glasses containing a high level of Fe 2 O 3 for use as a storage medium for high-level-radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste, a highly corrosion resistant, homogeneous, easily processed glass can be formed. For corroding solutions at 90 C, with solution pH values in the range between 5 and 9, the corrosion rate of the lead-iron phosphate nuclear waste glass is at least 10 2 to 10 3 times lower than the corrosion rate of a comparable borosilicate nuclear waste glass. The presence of Fe 2 O 3 in forming the lead-iron phosphate glass is critical. Lead-iron phosphate nuclear waste glass can be prepared at temperatures as low as 800 C, since they exhibit very low melt viscosities in the 800 to 1050 C temperature range. These waste-loaded glasses do not readily devitrify at temperatures as high as 550 C and are not adversely affected by large doses of gamma radiation in H 2 O at 135 C. The lead-iron phosphate waste glasses can be prepared with minimal modification of the technology developed for processing borosilicate glass nuclear waste forms. (author)

  10. International Congress on Glass XII

    Doremus, R H; LaCourse, W C; Mackenzie, J D; Varner, J R; Wolf, W W [eds.

    1980-01-01

    A total of 158 papers are included under nine headings: structure and glass formation; optical properties; electrical and magnetic properties; mechanical properties and relaxation; mass transport; chemical durability and surfaces; nucleation; crystallization; and glass ceramics; processing; and automatic controls. Separate abstracts were prepared for eight papers; four of the remaining papers had been processed previously for the data base. (DLC)

  11. Retention of Halogens in Waste Glass

    Hrma, Pavel R.

    2010-05-01

    In spite of their potential roles as melting rate accelerators and foam breakers, halogens are generally viewed as troublesome components for glass processing. Of five halogens, F, Cl, Br, I, and At, all but At may occur in nuclear waste. A nuclear waste feed may contain up to 10 g of F, 4 g of Cl, and ≤100 mg of Br and I per kg of glass. The main concern is halogen volatility, producing hazardous fumes and particulates, and the radioactive iodine 129 isotope of 1.7x10^7-year half life. Because F and Cl are soluble in oxide glasses and tend to precipitate on cooling, they can be retained in the waste glass in the form of dissolved constituents or as dispersed crystalline inclusions. This report compiles known halogen-retention data in both high-level waste (HLW) and low-activity waste (LAW) glasses. Because of its radioactivity, the main focus is on I. Available data on F and Cl were compiled for comparison. Though Br is present in nuclear wastes, it is usually ignored; no data on Br retention were found.

  12. Preparation and properties of Fe{sub 80−x}Ni{sub x}P{sub 14}B{sub 6} bulk metallic glasses

    Zhang, Ling; Ma, XiuHua [School of Physics Science and Technology, Xinjiang University, Urumqi, Xinjiang 830046 (China); Li, Qiang, E-mail: qli@xju.edu.cn [School of Physics Science and Technology, Xinjiang University, Urumqi, Xinjiang 830046 (China); Zhang, Jijun [School of Physics Science and Technology, Xinjiang University, Urumqi, Xinjiang 830046 (China); Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201 (China); Dong, Yaqiang; Chang, Chuntao [Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201 (China)

    2014-09-01

    Highlights: • Fe{sub 80−x}Ni{sub x}P{sub 14}B{sub 6} (x = 20–50 at.%) BMGs were prepared by fluxing and J-quenching techniques. • The highest GFA is reached at x = 40 and the corresponding critical diameter is up to 2.5 mm. • The present FeNi-based BMGs exhibit very large ε{sub p} and the ε{sub p} of Fe{sub 30}Ni{sub 50}P{sub 14}B{sub 6} BMG is 11.7%. • The present FeNi-based BMGs have much higher corrosion resistance than stainless steel. - Abstract: Bulk Fe{sub 80−x}Ni{sub x}P{sub 14}B{sub 6} (x = 20, 30, 40, 50 at.%) glassy alloy rods with the diameters of 1.0–2.5 mm were synthesized by combining fluxing technique and J-quenching technique. The glassy alloy rods were characterized by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and vibrating sample magnetometer (VSM). It is found that the range of supercooled liquid region (ΔT{sub x}) is 27–32 K. The saturation magnetization of Fe{sub 80−x}Ni{sub x}P{sub 14}B{sub 6} (x = 20, 30, 40, 50 at.%) bulk glassy alloys gradually decreases from 1.13 T to 0.58 T with increasing Ni content from x = 20 to x = 50. More importantly, the present quaternary FeNiPB bulk metallic glasses (BMGs) shows a significant plastic strain, in particular, the plastic strain of Fe{sub 30}Ni{sub 50}P{sub 14}B{sub 6} BMG reaches as high as 11.7%. The corrosion resistance of the present FeNiPB BMGs was studied by weight-loss method, potentiodynamic polarization curves and scanning electron microscopy (SEM). It is shown that the corrosion resistance of the present FeNiPB BMGs in 0.5 M NaCl and 1 M HCl solution increases with Ni content, and further the present FeNiPB BMGs exhibit larger E{sub corr} values and lower I{sub corr} values, i.e. higher corrosion resistances, than that of stainless steel.

  13. Predictive modeling of crystal accumulation in high-level waste glass melters processing radioactive waste

    Matyáš, Josef; Gervasio, Vivianaluxa; Sannoh, Sulaiman E.; Kruger, Albert A.

    2017-11-01

    The effectiveness of HLW vitrification is limited by precipitation/accumulation of spinel crystals [(Fe, Ni, Mn, Zn)(Fe, Cr)2O4] in the glass discharge riser of Joule-heated ceramic melters during idling. These crystals do not affect glass durability; however, if accumulated in thick layer, they can clog the melter and prevent discharge of molten glass into canisters. To address this problem, an empirical model was developed that can predict thicknesses of accumulated layers as a function of glass composition. This model predicts well the accumulation of single crystals and/or small-scale agglomerates, but, excessive agglomeration observed in high-Ni-Fe glass resulted in an under-prediction of accumulated layers, which gradually worsen over time as an increased number of agglomerates formed. Accumulation rate of ~53.8 ± 3.7 µm/h determined for this glass will result in ~26 mm thick layer in 20 days of melter idling.

  14. Product consistency testing of three reference glasses in stainless steel and perfluoroalkoxy resin vessels

    Olson, K.M.; Smith, G.L.; Marschman, S.C.

    1995-03-01

    Because of their chemical durability, silicate glasses have been proposed and researched since the mid-1950s as a medium for incorporating high-level radioactive waste (HLW) generated from processing of nuclear materials. A number of different waste forms were evaluated and ranked in the early 1980s; durability (leach resistance) was the highest weighted factor. Borosilicate glass was rated the best waste form available for incorporation of HLW. Four different types of vessels and three different glasses were used to study the possible effect of vessel composition on durability test results from the Production Consistency Test (PCT). The vessels were 45-m 304 stainless steel vessels, 150-m 304 L stainless steel vessels, and 60-m perfluoroalkoxy (PFA) fluoropolymer resin vessels. The three glasses were the Environmental Assessment glass manufactured by Corning Incorporated and supplied by Westinghouse Savannah River company, and West Valley Nuclear Services reference glasses 5 and 6, manufactured and supplied by Catholic University of America. Within experimental error, no differences were found in durability test results using the 3 different glasses in the 304L stainless steel or PFA fluoropolymer resin vessels over the seven-day test period

  15. High-level waste borosilicate glass a compendium of corrosion characteristics. Volume 1

    Cunnane, J.C.

    1994-03-01

    Current plans call for the United States Department of Energy (DOE) to start up facilities for vitrification of high-level radioactive waste (HLW) stored in tanks at the Savannah River Site, Aiken, South Carolina, in 1995; West Valley Demonstration Project, West Valley, New York, in 1996; and at the Hanford Site, Richland, Washington, after the year 2000. The product from these facilities will be canistered HLW borosilicate glass, which will be stored, transported, and eventually disposed of in a geologic repository. The behavior of this glass waste product, under the range of likely service conditions, is the subject of considerable scientific and public interest. Over the past few decades, a large body of scientific information on borosilicate waste glass has been generated worldwide. The intent of this document is to consolidate information pertaining to our current understanding of waste glass corrosion behavior and radionuclide release. The objective, scope, and organization of the document are discussed in Section 1.1, and an overview of borosilicate glass corrosion is provided in Section 1.2. The history of glass as a waste form and the international experience with waste glass are summarized in Sections 1.3 and 1.4, respectively

  16. The xGa{sub 2}O{sub 3}–(100 − x)NaPO{sub 3} glass system: Preparation, properties and structural analysis by solid state NMR

    Caron, A. [UCCS UMR-CNRS 8181, Université de Lille1, Villeneuve d' Ascq (France); Doumert, B. [IMMCL, Université de Lille1, Villeneuve d' Ascq (France); Tricot, G., E-mail: gregory.tricot@univ-lille1.fr [UCCS UMR-CNRS 8181, Université de Lille1, Villeneuve d' Ascq (France); LASIR UMR-CNRS 8516, Université de Lille1, Villeneuve d' Ascq (France)

    2014-10-15

    Insertion of Ga{sub 2}O{sub 3} in sodium metaphosphate glasses has been investigated in this paper. Materials containing up to 30 mol% of Ga{sub 2}O{sub 3} have been prepared using the standard melt-quenching technique within the xGa{sub 2}O{sub 3}–(100 − x)NaPO{sub 3} composition line. Macroscopic properties (glass transition temperature, density and molar volume) are significantly affected by the Ga{sub 2}O{sub 3} insertion. 1D {sup 71}Ga and {sup 31}P magic angle spinning nuclear magnetic resonance (MAS-NMR) performed at very high field (18.8 T) indicate a strong evolution of the gallium coordination state around the x = 15 composition and a continuous evolution of the phosphate network organisation. In addition, {sup 71}Ga({sup 31}P) D-HMQC NMR technique was used for the first time to highlight the presence of mixed P–O–Ga linkages within the glass structure. The impact of gallium insertion is finally discussed and compared to the effect of the widely used aluminum and boron elements. If gallium and aluminum elements present similar effect on the macroscopic properties, some discrepancies can be observed concerning their structural effect. - Highlights: • Glasses with 30 mol% of Ga{sub 2}O{sub 3} have been prepared in the NaPO{sub 3}–Ga{sub 2}O{sub 3} line. • T{sub g} and density are affected by the Ga{sup 3+} insertion. • Presence of mixed Ga/P species have been highlighted by 2D correlation NMR.

  17. High Level Waste (HLW) Processing Experience with Increased Waste Loading

    JANTZEN, CAROL

    2004-01-01

    The Defense Waste Processing Facility (DWPF) Engineering requested characterization of glass samples that were taken after the second melter had been operational for about 5 months. After the new melter had been installed, the waste loading had been increased to about 38 weight percentage after a new quasicrystalline liquidus model had been implemented. The DWPF had also switched from processing with refractory Frit 200 to a more fluid Frit 320. The samples were taken after DWPF observed very rapid buildup of deposits in the upper pour spout bore and on the pour spout insert while processing the high waste loading feedstock. These samples were evaluated using various analytical techniques to determine the cause of the crystallization. The pour stream sample was homogeneous, amorphous, and representative of the feed batch from which it was derived. Chemical analysis of the pour stream sample indicated that a waste loading of 38.5 weight per cent had been achieved. The data analysis indicated that surface crystallization, induced by temperature and oxygen fugacity gradients in the pour spout, caused surface crystallization to occur in the spout and on the insert at the higher waste loadings even though there was no crystallization in the pour stream

  18. Spheroidization of glass powders for glass ionomer cements.

    Gu, Y W; Yap, A U J; Cheang, P; Kumar, R

    2004-08-01

    Commercial angular glass powders were spheroidized using both the flame spraying and inductively coupled radio frequency plasma spraying techniques. Spherical powders with different particle size distributions were obtained after spheroidization. The effects of spherical glass powders on the mechanical properties of glass ionomer cements (GICs) were investigated. Results showed that the particle size distribution of the glass powders had a significant influence on the mechanical properties of GICs. Powders with a bimodal particle size distribution ensured a high packing density of glass ionomer cements, giving relatively high mechanical properties of GICs. GICs prepared by flame-spheroidized powders showed low strength values due to the loss of fine particles during flame spraying, leading to a low packing density and few metal ions reacting with polyacrylic acid to form cross-linking. GICs prepared by the nano-sized powders showed low strength because of the low bulk density of the nano-sized powders and hence low powder/liquid ratio of GICs.

  19. Concept of grouping in partitioning of HLW for self-consistent fuel cycle

    Kitamoto, A.; Mulyanto

    1993-01-01

    A concept of grouping for partitioning of HLW has been developed in order to examine the possibility of a self-consistent fuel recycle. The concept of grouping of radionuclides is proposed herein, such as Group MA1 (MA below Cm), Group MA2 (Cm and higher MA), Group A ( 99 Tc and I), Group B (Cs and Sr) and Group R (the partitioned remain of HLW). Group B is difficult to be transmuted by neutron reaction, so a radiation application in an industrial scale should be developed in the future. Group A and Group MA1 can be burned by a thermal reactor, on the other hand Group MA2 should be burned by a fast reactor. P-T treatment can be optimized for the in-core and out-core system, respectively

  20. Compas project stress analysis of HLW containers: behaviour under realistic disposal conditions

    Ove Arup and Partners, London

    1990-01-01

    The Compas project is concerned with the structural performance of metal overpacks which may be used to encapsulate vitrified high-level waste (HLW) forms before disposal in deep geological repositories. In this final stage of the project, analysis of an HLW overpack of realistic design is performed to predict its behaviour when subjected to likely repository loads. This analysis work is undertaken with the benefit of experience gained in previous phases of the project in which the ability to accurately predict overpack behaviour, when subjected to a uniform external pressure, was demonstrated. Burial in clay, granite and salt environments has been considered and two distinct loading arrangements identified, in an attempt to represent the worst conditions that could be imposed by such media. The analysis successfully demonstrates the ability of the containers to withstand extreme, yet credible, repository loads

  1. Study on the properties of Gaomiaozi bentonite as the buffer/backfilling materials for HLW disposal

    Liu Xiaodong; Luo Taian; Zhu Guoping; Chen Qingchun

    2007-12-01

    Systematic studies including mineral composition and structure, physico- chemical properties and thermal properties have been conducted on Gaomiaozi bentonite, Xinghe County, Inner Mongolia Autonomous Region. The compaction characteristics of bentonite and the influence of additive to bentonite have been discussed. The analysis of mineral composition and structure show that the bentonite ores are dominated by montmorillonite. Preliminary studies of the characteristics of ores indicated that No-type bentonite from the deposit has good absorption, excellent swelling and high cation exchangeability. The compressibility of bentonite will be improved by adding the additives such as quartz sand. The studies indicated that the characteristics of Gaomiaozi bentonite can satisfy the requirement of buffer/backfilling materials for HLW repository and the ores can be selected as the preferential candidate to provide buffer/backfill- ing materials for HLW repository in China. (authors)

  2. The interpretation of remote sensing image on the stability of fault zone at HLW repository site

    Liu Linqing; Yu Yunxiang

    1994-01-01

    It is attempted to interpret the buried fault at the preselected HLW repository site in western Gansu province with a remote sensing image. The authors discuss the features of neotectonism of Shule River buried fault zone and its two sides in light of the remote sensing image, geomorphology, stream pattern, type and thickness difference of Quaternary sediments, and structural basin, etc.. The stability of Shule River fault zone is mainly dominated by the neotectonic movement pattern and strength of its two sides. Although there exist normal and differential vertical movements along it, their strengths are small. Therefore, this is a weakly-active passive fault zone. The east Beishan area north to Shule River fault zone is weakliest active and is considered as the target for further pre-selection for HLW repository site

  3. Study on the properties of Gaomiaozi bentonite as the buffer/backfilling materials for HLW disposal

    Xiaodong, Liu [East China Inst. of Technology, Fuzhou (China); [Key Laboratory of Nuclear Resources and Environment of Ministry of Education, Fuzhou (China); Taian, Luo; Guoping, Zhu; Qingchun, Chen [East China Inst. of Technology, Fuzhou (China)

    2007-12-15

    Systematic studies including mineral composition and structure, physico- chemical properties and thermal properties have been conducted on Gaomiaozi bentonite, Xinghe County, Inner Mongolia Autonomous Region. The compaction characteristics of bentonite and the influence of additive to bentonite have been discussed. The analysis of mineral composition and structure show that the bentonite ores are dominated by montmorillonite. Preliminary studies of the characteristics of ores indicated that No-type bentonite from the deposit has good absorption, excellent swelling and high cation exchangeability. The compressibility of bentonite will be improved by adding the additives such as quartz sand. The studies indicated that the characteristics of Gaomiaozi bentonite can satisfy the requirement of buffer/backfilling materials for HLW repository and the ores can be selected as the preferential candidate to provide buffer/backfill- ing materials for HLW repository in China. (authors)

  4. Current status and future plans of R and D on geological disposal of HLW in Japan

    Sasaki, Noriaki

    1994-01-01

    As to the final disposal of HLW, it is considered highly important to provide a clear distinction between implementation of disposal and the research and development as independent processes, and to increase the transparency of the overall disposal program by defining concrete schedules and the roles and responsibilities of the organizations involved. The Power Reactor and Nuclear Fuel Development Corporation (PNC) has being conducted research and development on the geological disposal of HLW, as the leading organization. The responsibility of PNC is to ensure smooth progress of research and development project and to carry out studies of geological environment. The role of the Japanese government is to take overall responsibilities for appropriate and steady implementations of the program, as well as enacting any laws or policies required. On the other hand, electricity supply utilities are responsible to secure necessary funds for disposal, and in accordance with their role as waste producers, they are expected to cooperate even at the stage of research and development. Fundamental features of research and development of PNC carried out at this stage are as follows; (1) Generic research and development, (2) To establish scientific and technical bases of geological isolation of HLW in Japan, (3) About 15 years program from 1989 with documentation of progress reports, (4) Approach from near-field to far-field. PNC summarized the findings obtained by 1991, and submitted a document (H3 Report) in September 1992 as the first progress report. H3 Report is the first and comprehensive technical report on geological disposal of HLW in Japan, and provides information for the public to find out the current status of the research and development. This paper reviews the conclusions of H3 Report, overall procedures and schedule for implementing geological disposal, and future plans of R and D in PNC. (J.P.N.)

  5. Chemical composition analysis and product consistency tests supporting refinement of the Nepheline Model for the high aluminum Hanford glass composition region

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Edwards, T. B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Mcclane, D. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-03-01

    In this report, Savannah River National Laboratory provides chemical analyses and Product Consistency Test (PCT) results for a series of simulated high level waste (HLW) glasses fabricated by Pacific Northwest National Laboratory (PNNL) as part of an ongoing nepheline crystallization study. The results of these analyses will be used to improve the ability to predict crystallization of nepheline as a function of composition and heat treatment for glasses formulated at high alumina concentrations.

  6. Chemical composition analysis and product consistency tests supporting refinement of the Nepheline model for the high aluminum Hanford Glass composition region

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States); Edwards, T. B. [Savannah River Site (SRS), Aiken, SC (United States); Mcclane, D. L. [Savannah River Site (SRS), Aiken, SC (United States)

    2016-02-17

    In this report, SRNL provides chemical analyses and Product Consistency Test (PCT) results for a series of simulated HLW glasses fabricated by Pacific Northwest National Laboratory (PNNL) as part of an ongoing nepheline crystallization study. The results of these analyses will be used to improve the ability to predict crystallization of nepheline as a function of composition and heat treatment for glasses formulated at high alumina concentrations.

  7. Development of a Korean Reference disposal System(A-KRS) for the HLW from Advanced Fuel Cycles

    Choi, Heui Joo; Choi, J. W.; Lee, J. Y.

    2010-04-01

    A database program for analyzing the characteristics of spent fuels was developed, and A-SOURCE program for characterizing the source term of HLW from advanced fuel cycles. A new technique for developing a copper canister by introducing a cold spray technique was developed, which could reduce the amount of copper. Also, to enhance the performance of A-KRS, two kinds of properties, thermal performance and iodine adsorption, were studied successfully. A complex geological disposal system which can accommodate all the HLW (CANDU and HANARO spent fuels, HLW from pyro-processing of PWR spent fuels, decommissioning wastes) was developed, and a conceptual design was carried out. Operational safety assessment system was constructed for the long-term management of A-KRS. Three representative accidental cases were analyzed, and the probabilistic safety assessment was adopted as a methodology for the safety evaluation of A-KRS operation. A national program was proposed to support the HLW national policy on the HLW management. A roadmap for HLW management was proposed based on the optimum timing of disposal

  8. Recycle Glass in Foam Glass Production

    Petersen, Rasmus Rosenlund; König, Jakob; Yue, Yuanzheng

    The foam glass industry turn recycle glass into heat insulating building materials. The foaming process is relative insensitive to impurities in the recycle glass. It is therefore considered to play an important role in future glass recycling. We show and discuss trends of use of recycled glasses...... in foam glass industry and the supply sources and capacity of recycle glass....

  9. A Glass-Ceramic Waste Forms for the Immobilization of Rare Earth Oxides from the Pyroprocessing Waste salt

    Ahn, Byung-Gil; Park, Hwan-Seo; Kim, Hwan-Young; Kim, In-Tae

    2008-01-01

    The fission product of rare earth (RE) oxide wastes are generates during the pyroprocess . Borosilicate glass or some ceramic materials such as monazite, apatite or sodium zirconium phosphate (NZP) have been a prospective host matrix through lots of experimental results. Silicate glasses have long been the preferred waste form for the immobilization of HLW. In immobilization of the RE oxides, the developed process on an industrial scale involves their incorporation into a glass matrix, by melting under 1200 ∼ 1300 .deg. C. Instead of the melting process, glass powder sintering is lower temperature (∼ 900 .deg. C) required for the process which implies less demanding conditions for the equipment and a less evaporation of volatile radionuclides. This study reports the behaviors, direct vitrification of RE oxides with glass frit, glass powder sintering of REceramic with glass frit, formation of RE-apatite (or REmonazite) ceramic according to reaction temperature, and the leach resistance of the solidified waste forms

  10. The use of mineral-like matrices for hlw solidification and spent fuel immobilization

    Pokhitonov, J.A.; Starchenko, V.A.; Strelnikov, A.V.; Sorokin, V.T.; Shvedov, A.A.

    2000-01-01

    The conception of radioactive waste management is based upon the multi-barrier protection principle stating that the long-lived radionuclides safety isolation is ensured by a system of engineering and natural geological barriers. One of the effective ways of the long-lived radionuclides immobilization is the integration of these materials within a mineral-like matrice. This technique may be used both for isolation of separated groups of nuclides (Cs, Sr, TUE, TRE) and for immobilization of spent fuel which for some reason can't be processed at the radiochemical plant. In this paper two variants of flowsheets HLW management are discussed. The following ways of HLW reprocessing are considered: - The first cycle raffinate solidification (without partitioning); - The individual solidification of two separated radionuclide groups (Sr+Cs+FP fraction and TPE+TRE fraction). The calcination of some characteristics (annual and total amounts, specific activity, radiochemical composition and radiogenic heat) of HLW integrated within a mineral-like matrix are performed for both options. The matrix compositions may be also used for spent fuel immobilization by means of the hot isostatic pressing technique. (authors)

  11. Researches on tectonic uplift and denudation with relation to geological disposal of HLW in Japan

    Fujiwara, Osamu; Sanga, Tomoji; Moriya, Toshifumi

    2005-01-01

    This paper reviews the present state of researches on tectonic uplift and denudation, and shows perspective goals and direction of future researches from the viewpoint of geological disposal of HLW in Japan. Detailed history of tectonics and denudation in geologic time scale, including the rates, temporal and spatial distributions and processes, reconstructed from geologic and geomorphologic evidences will enable us to make the geological predictions. Improvements of the analytic methods for the geological histories, e.g. identification of the tectonic and denudational imprints and age determinations, are indispensable for the accurate prediction. Developments of the tools and methodologies for assessments of the degree and extension of influences by the tectonic uplift, subsidence and denudation on the geological environments such as ground water flows are also fundamental problem in the study field of the geological disposal of HLW. Collaboration of scientific researches using the geological and geomorphological methods and applied technology, such as numerical simulations of ground water flows, is important in improving the safety and accuracy of the geological disposal of HLW. (author)

  12. The senate working party on HLW management in Spain - historical perspective

    Lang-Lenton, J.

    2007-01-01

    As the first case history Jorge Lang Lenton, Corporate Director of ENRESA, recounted the failed attempt to establish an underground disposal facility for HLW. The site selection process, which was planned by ENRESA in the 1980's, was aimed at finding the 'technically best' site. The process was conducted by technical experts without public involvement. When 40 candidate siting areas were identified in the mid-1990's, information leaked out, creating vigorous public opposition in all of these locations. In 1998 the siting process was halted. The Senate proposed to continue R and D on geological disposal and on P and T, to reduce waste production, and to develop an energy policy that relies more on renewable energy sources. They also suggested that public participation be promoted. The 5. General Radioactive Waste Management Plan, which was developed in 1999, took these proposals into consideration. Regarding underground disposal, the government postponed any decision until 2010. At the end of 2004 a decision was made by Parliament to establish a centralized storage facility for HLW. Mr. Lang-Lenton highlighted the main lessons of the failed siting attempt. First, it has to be acknowledged that HLW management is a societal rather than a technical problem. Second, for any radioactive waste management facility a socially feasible rather than a technically optimal site should be selected, i.e., 'the best site is the possible site'. Finally, transparency and openness are needed for building confidence in the decision-making process. (author)

  13. Accelerated Leach Testing of GLASS: ALTGLASS Version 3.0

    Trivelpiece, Cory L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Jantzen, Carol M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Crawford, Charles L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-12-31

    The Accelerated Leach Testing of GLASS (ALTGLASS) database is a collection of data from short- and long-term product consistency tests (PCT, ASTM C1285 A and B) on high level waste (HLW) as well as low activity waste (LAW) glasses. The database provides both U.S. and international researchers with an archive of experimental data for the purpose of studying, modeling, or validating existing models of nuclear waste glass corrosion. The ALTGLASS database is maintained and updated by researchers at the Savannah River National Laboratory (SRNL). This newest version, ALTGLASS Version 3.0, has been updated with an additional 503 rows of data representing PCT results from corrosion experiments conducted in the United States by the Savannah River National Laboratory, Pacific Northwest National Laboratory, Argonne National Laboratory, and the Vitreous State Laboratory (SRNL, PNNL, ANL, VSL, respectively) as well as the National Nuclear Laboratory (NNL) in the United Kingdom.

  14. Accelerated Leach Testing of GLASS: ALTGLASS Version 3.0

    Trivelpiece, Cory L.; Jantzen, Carol M.; Crawford, Charles L.

    2016-01-01

    The Accelerated Leach Testing of GLASS (ALTGLASS) database is a collection of data from short- and long-term product consistency tests (PCT, ASTM C1285 A and B) on high level waste (HLW) as well as low activity waste (LAW) glasses. The database provides both U.S. and international researchers with an archive of experimental data for the purpose of studying, modeling, or validating existing models of nuclear waste glass corrosion. The ALTGLASS database is maintained and updated by researchers at the Savannah River National Laboratory (SRNL). This newest version, ALTGLASS Version 3.0, has been updated with an additional 503 rows of data representing PCT results from corrosion experiments conducted in the United States by the Savannah River National Laboratory, Pacific Northwest National Laboratory, Argonne National Laboratory, and the Vitreous State Laboratory (SRNL, PNNL, ANL, VSL, respectively) as well as the National Nuclear Laboratory (NNL) in the United Kingdom.

  15. Database for waste glass composition and properties

    Peters, R.D.; Chapman, C.C.; Mendel, J.E.; Williams, C.G.

    1993-09-01

    A database of waste glass composition and properties, called PNL Waste Glass Database, has been developed. The source of data is published literature and files from projects funded by the US Department of Energy. The glass data have been organized into categories and corresponding data files have been prepared. These categories are glass chemical composition, thermal properties, leaching data, waste composition, glass radionuclide composition and crystallinity data. The data files are compatible with commercial database software. Glass compositions are linked to properties across the various files using a unique glass code. Programs have been written in database software language to permit searches and retrievals of data. The database provides easy access to the vast quantities of glass compositions and properties that have been studied. It will be a tool for researchers and others investigating vitrification and glass waste forms

  16. The Effects of Oxygen Partial Pressure on Liquidus Temperature of a High-Level Waste Glass with Spinel as the Primary Phase

    Izak, Pavel; Hrma, Pavel R.; Wilson, Benjamin K.; Vienna, John D.

    2000-01-01

    The redox state of iron affects spinal crystallization in vitrified high-level waste (HLW) glass. Simulated HLW glass with spinel as the primary crystalline phase field was heat treated at constant temperatures within the interval from 850 C to 1300 C under varying atmospheres with oxygen partial pressure, Po2, ranging from 1x10-16 kPa (pure CO) to 101 kPa (pure O2). Liquidus temperature (TL) of glass increased with decreasing Po2 up to Po2 > 3 x 10-9 kPa. At Po2 < 3 x 10-9 kPa, Ni-Fe alloy precipitated from the glass, and TL decreased. Samples were analyzed with optical microscope and scanning electron microscope. The mass fraction of spinel in glass was determined using quantitative X-ray diffraction. Spinel composition was investigated with energy disperse spectroscopy. Ferrous-ferric equilibrium at TL was calculated in a HLW glass as a function of temperature and Po2, based on the previous studies by Schreiber. TL/FeO over the interval 0.0063 < gFeO < 0.051 (1x10-2 kPa < Po2 < 3x10-9 kPa) was estimated from calculated ferrous-ferric equilibrium at TL as 1835 C

  17. Direct conversion of plutonium metal, scrap, residue, and transuranic waste to glass

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.; Malling, J.F.; Rudolph, J.

    1995-01-01

    A method for the direct conversion of metals, ceramics, organics, and amorphous solids to borosilicate glass has been invented. The process is called the Glass Material Oxidation and Dissolution System (GMODS). Traditional glass-making processes can convert only oxide materials to glass. However, many wastes contain complex mixtures of metals, ceramics, organics, and amorphous solids. Conversion of such mixtures to oxides followed by their conversion to glass is often impractical. GMODS may create a practical method to convert such mixtures to glass. Plutonium-containing materials (PCMS) exist in many forms, including metals, ceramics, organics, amorphous solids, and mixtures thereof. These PCMs vary from plutonium metal to filters made of metal, organic binders, and glass fibers. For storage and/or disposal of PCMS, it is desirable to convert PCMs to borosilicate glass. Borosilicate glass is the preferred repository waste form for high-level waste (HLW) because of its properties. PCMs converted to a transuranic borosilicate homogeneous glass would easily pass all waste acceptance and storage criteria. Conversion of PCMs to a glass would also simplify safeguards by conversion of heterogeneous PCMs to homogeneous glass. Thermodynamic calculations and proof-of-principle experiments on the GMODS process with cerium (plutonium surrogate), uranium, stainless steel, aluminum, Zircaloy-2, and carbon were successfully conducted. Initial analysis has identified potential flowsheets and equipment. Major unknowns remain, but the preliminary data suggests that GMODS may be a major new treatment option for PCMs

  18. Cosmos & Glass

    Beim, Anne

    1996-01-01

    The article unfolds the architectural visions of glass by Bruno Taut. It refers to inspirations by Paul Sheerbart and litterature and the Crystal Chain, also it analyses the tectonic univers that can be found in the glass pavillion for the Werkbund exposition in Cologne....

  19. Glass Glimpsed

    Lock, Charles

    2015-01-01

    Glass in poetry as it reflects the viewer and as its power of reflection are both reduced and enhanced by technology.......Glass in poetry as it reflects the viewer and as its power of reflection are both reduced and enhanced by technology....

  20. Characteristics of borosilicate waste glass form for high-level radioactive waste

    Kim, Seung Soo; Chun, Kwan Sik; Choi, Jong Won; Kang, Chul Hyung

    2001-03-01

    Basic data, required for the design and the performance assessment of a repository of HLW, suchas the chemical composition and the characteristics of the borosilicate waste glass have been identified according to the burn-ups of spent PWR fuels. The diemnsion of waste canister is 430mm in diameter and 1135mm in length, and the canister should hold less than 2kwatts of heat from their decay of radionuclides contained in the HLW. Based on the reprocessing of 5 years-cooled spent fuel, one canister could hold about 11.5wt.% and 10.8wt.% of oxidized HLW corresponding to their burn-ups of 45,000MWD/MTU and 55,000MWD/MTU, respectively. These waste forms have been recommanded as the reference waste forms of HLW. The characteristics of these wastes as a function of decay time been evaluated. However, after a specific waste form and a specific site for the disposal would be selected, the characteristics of the waste should be reevaluated under the consideration of solidification period, loaded waste, storage condition and duration, site circumstances for the repository system and its performance assessment.

  1. Spin glasses

    Bovier, Anton

    2007-01-01

    Spin glass theory is going through a stunning period of progress while finding exciting new applications in areas beyond theoretical physics, in particular in combinatorics and computer science. This collection of state-of-the-art review papers written by leading experts in the field covers the topic from a wide variety of angles. The topics covered are mean field spin glasses, including a pedagogical account of Talagrand's proof of the Parisi solution, short range spin glasses, emphasizing the open problem of the relevance of the mean-field theory for lattice models, and the dynamics of spin glasses, in particular the problem of ageing in mean field models. The book will serve as a concise introduction to the state of the art of spin glass theory, usefull to both graduate students and young researchers, as well as to anyone curious to know what is going on in this exciting area of mathematical physics.

  2. Preparation and Characterization of PbO-SrO-Na2O-Nb2O5-SiO2 Glass Ceramics Thin Film for High-Energy Storage Application

    Tan, Feihu; Zhang, Qingmeng; Zhao, Hongbin; Wei, Feng; Du, Jun

    2018-03-01

    PbO-SrO-Na2O-Nb2O5-SiO2 (PSNNS) glass ceramic thin films were prepared by pulsed laser deposition technology on heavily doped silicon substrates. The influence of annealing temperatures on microstructures, dielectric properties and energy storage performances of the as-prepared films were investigated in detail. X-ray diffraction studies indicate that Pb2Nb2O7 crystallizes at 800°C and disappears at 900°C, while NaNbO3 and PbNb2O6 are formed at the higher temperature of 900°C. The dielectric properties of the glass ceramics thin films have a strong dependence on the phase assemblages that are developed during heat treatment. The maximum dielectric constant value of 171 was obtained for the film annealed at 800°C, owing to the high electric breakdown field strength, The energy storage densities of the PSNNS films annealed at 800°C were as large as 36.9 J/cm3, These results suggest that PSNNS thin films are promising for energy storage applications.

  3. Effect of Gamma Irradiation on Some Properties of Bismuth Silicate Glasses and Their Glass Derivatives

    Abo Hussein, E.M.K.

    2014-01-01

    Glasses containing bismuth oxide have attracted considerable attention, although it is non-conventional glass forming oxide, but it has wide applications. In this work, it is aimed to prove that bismuth silicate glass can act as a good shielding material for γ- rays. For this purpose glass containing 20% bismuth oxide and 80% SiO_2 was prepared using melting-annealing technique. Also effects of adding some alkali heavy metal oxides to this glass such as PbO, BaO or SrO were also studied. The formed glasses were also heat treated at 450 degree C for 4 hours to give the corresponding heat treated glasses. Electron Paramagnetic Resonance (EPR) measurements show that the prepared glasses and heat treated glasses have very good stability when exposed to γ- irradiation, which encourage the assumption of using these glasses as gamma ray shielding materials. Many properties have been investigated, such as density to understand the structural properties, also mechanical properties were verified by measuring microhardness, while the chemical resistance was identified by testing their durability in both acidic and basic solutions. The EPR results were supported by measuring electrical conductivity of the glass and heat treated glass samples at different temperatures ranging from 298 to 553 K, which proved that these glasses have very low conductivity even at high temperature. The formed phases of heat treated glass or glass ceramic samples were demonstrated by means of X-ray diffraction (XRD). Also studying the structure of glasses and heat treated glasses before and after irradiation was investigated by the Infrared transmitting spectra. Calculations of optical band gap energies were demonstrated for some selected glasses and heat treated glasses from the data of UV optical absorption spectra to support the probability of using these bismuth silicate glasses for gamma radiation shielding processing.

  4. Influence of sintering temperature on microstructures and energy-storage properties of barium strontium titanate glass-ceramics prepared by sol-gel process

    Zhu, Jia; Zhang, Yong; Song, Xiaozhen; Zhang, Qian; Yang, Dongliang; Chen, Yongzhou [Beijing Key Laboratory of Fine Ceramics, State Key Laboratory of New Ceramics and Fine Processing, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084 (China)

    2015-12-15

    The sol-gel processing, microstructures, dielectric properties and energy-storage properties of barium strontium titanate glass-ceramics over the sintering temperature range of 1000-1150 C were studied. Through the X-ray diffraction result, it is revealed that the crystallinity increases as the sintering temperature increased from 1000 to 1080 C and has reached a steady-state regime above 1100 C. Scanning electron microscopy images showed that with the increase of sintering temperature, the crystal size increased. Dielectric measurements revealed that the increase in the sintering temperature resulted in a significant increase in the dielectric constant, a strong sharpness of the temperature-dependent dielectric response and a pronounced decrease of the temperature of the dielectric maximum. The correlation between charge spreading behavior and activation energies of crystal and glass was discussed by the employment of the impedance spectroscopy studies. As a result of polarization-electric field hysteresis loops, both the charged and discharged densities increased with increasing sintering temperature. And the maximum value of energy storage efficiency was found to occur at 1130 C. Finally, the dependence of released energy and power densities calculated from the discharged current-time (I-t) curves on the sintering temperature was studied. The relationship between the energy storage properties and microstructure was correlated. Polarization-electric field hysteresis loops for the BST glass-ceramics sintered at different temperatures. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Fabrication and characterization of MCC approved testing material - ATM-12 glass

    Wald, J.W.

    1985-10-01

    The Materials Characterization Center (MCC) Approved Testing Material ATM-12 is a borosilicate glass that incorporates elements typical of high-level waste (HLW) resulting from the reprocessing of commercial nuclear reactor fuels. The composition has been adjusted to match that predicted for HLW type 76-68 glass at an age of 300 y. Radioactive constituents contained in this glass include depleted uranium, 99 Tc, 237 Np, 239 Pu, and 241 Am. The glass was produced by the MCC at the Pacific Northwest Laboratory (PNL). ATM-12 glass ws produced from July to November of 1984 at the request of the Nevada Nuclear Waste Site Investigations (NNWSI) Program and is the third in a series of glasses produced for NNWSI. Most of the glass produced was in the form of cast bars; special castings and crushed material were also produced. Three kilograms of ATM-12 glass were produced from a feedstock melted in a nitrogen-atmosphere glove box at 1150 0 C in a platinum crucible, and formed into stress-annealed rectangular bars and the special casting shapes requested by NNWSI. Bars of ATM-12 were nominally 1.9 x 1.9 x 10 cm, with an average mass of 111 g each. Nineteen bars and 37 special castings were made. ATM-12 glass has been provided to the NNWSI Program, in the form of bars, crushed powder and special castings. As of August 1985 approximately 590 g of ATM-12 is available for distribution. Requests for materials or services related to this glass should be directed to the Materials Characterization Center Program Office, PNL

  6. Influence of the glass-calcium carbonate mixture's characteristics on the foaming process and the properties of the foam glass

    König, Jakob; Petersen, Rasmus Rosenlund; Yue, Yuanzheng

    2014-01-01

    We prepared foam glasses from cathode-ray-tube panel glass and CaCO3 as a foaming agent. We investigated the influences of powder preparation, CaCO3 concentration and foaming temperature and time on the density, porosity and homogeneity of the foam glasses. The results show that the decomposition...

  7. GLASS BOX

    Curtis, Laura

    2008-01-01

    The goals of this effort were to develop Glass Box capabilities to allow for the capturing of analyst activities and the associated data resources, track and log the results of automated processing...

  8. Actinide partitioning from HLW in a continuous DIDPA extraction process by means of centrifugal extractors

    Morita, Y.; Kubota, M.; Glatz, J.P.; Koch, L.; Pagliosa, G.; Roemer, K.; Nicholl, A.

    1996-01-01

    An experiment on actinide partitioning from real high level waste (HLW) was performed in a continuous process by extraction with diisodecylphosphoric acid (DIDPA) using a battery of 12 centrifugal extractors installed in a hot cell. The HNO 3 concentration of the HLW was adjusted to 0.5 M by dilution. The extraction section had 8 stages, and H 2 O 2 was added to extract Np effectively. After extraction, Am and Cm were back-extracted with 4 M HNO 3 in 4 stages and Np and Pu were stripped with 0.8 M H 2 C 2 O 4 in 8 stages. The actinides, expect Np, were extracted from HLW with a very high yield. Although only 84% of the Np were recovered in the present experiment, the recovery would be improved to 99.7 % by increasing the temperature to 45 degree C, the number of stages from 8 to 16 and the H 2 O 2 concentration from 1 M to 2 M. Long-lived Tc and the main heat and radiation emitters Cs and Sr were not extracted and were thus separated from the actinides with high decontamination factors. About 98% of Am and Cm were recovered from the loaded solvent in the first stripping step with 4M HNO 3 . About 86% of Np and about 92% of Pu were back-extracted with 0.8 M H 2 C 2 O 4 . These incomplete recoveries would be improved by increasing the number of stages and by optimizing the other process parameters. 18 refs., 5 figs., 3 tabs

  9. Cost effects of Cu powder and bentonite on the disposal costs of an HLW repository in

    Kim, Sung Ki; Lee, Min Soo; Lee, Jong Youl; Choi, Heui Joo; Choi, Jong Won

    2008-01-01

    This paper provides the cost effect results of Cu powder and bentonite on the disposal cost for an HLW repository in Korea. In the cost analysis for both of these cost drivers, the price of Cu powder and the bentonite can affect the canister cost and the bentonite cost of the disposal holes as well as backfilling cost of the tunnels, respectively. Finally, we found that the unit cost of Cu and bentonite was the dominant cost drivers for the surface and underground facilities of an HLW repository. Therefore, an optimization of a canister and the layout of a disposal hole and disposal tunnels are essential to decrease the direct disposal cost of spent fuels. The disposal costs can be largely divided into two parts such as a surface facilities' cost and an underground facilities' cost. According to the KRS' cost analysis, the encapsulation material as well as the buffering and backfilling cost were the significant costs. Especially, a canister's cost was approximately estimated to be more than one fourth of the overall disposal costs. So it can be estimated that the unit cost of Cu powder is an important cost diver. Because the outer shell of the canister was made of Cu powder by a cold spray coating method. In addition, the unit cost of bentonite can also affect the buffering and the backfilling costs of the disposal holes and the disposal tunnels. But, these material costs will be highly expensive and unstable due to the modernization of the developing countries. So the studies for a material cost should be continued to identify the actual cost of an HLW repository

  10. An analytical overview of the consequences of microbial activity in a Swiss HLW repository

    McKinley, I.G.; West, J.M.; Grogan, H.A.

    1985-04-01

    Microorganisms are known to be important factors in many geochemical processes and their presence can be assured throughout the envisaged Swiss type C repository for HLW. It is likely that both introduced and resident microbes will colonise the near-field even at times when ambient temperature and radiation fields are relatively high. A simple quantitative model has been developed which indicates that microbial growth in the near-field is limited by the rate of supply of chemical energy from corrosion of the canister. Microbial processes examined include biodegradation of structural and packaging materials, alteration of groundwater chemistry (Eh, pH, organic complexant concentration) and direct nuclide uptake by microorganisms. The most important effects of such organisms are likely to be enhancement of release and mobility of key nuclides due to their complexation by microbial by-product. Resident micro-organisms in the far-field could potentially act as 9 living colloids' thus enhancing nuclide transport. In the case of flow paths through shear zones (kakirites), however, any microbes capable of penetrating the surrounding weathered rock matrix would be extensively retarded. It is concluded that microbial processes are unlikely to be of significance for HLW but will be more important for low/intermediate waste types. As data requirements are similar for all waste types, results from such studies would also resolve the main uncertainties remaining for the HLW case. Key research areas are identified as characterisation of a) nutrient availability in the near-field, b) the bioenergetics of iron corrosion, c) production of organic by-products, d) nuclide sorption by organisms and e) microbial mobility in the near-and far-field

  11. Application of QA to R ampersand D support of HLW programs

    Ryder, D.E.

    1988-01-01

    Quality has always been of primary importance in the research and development (R ampersand D) environment. An organization's ability to attract funds for new or continued research is largely dependent on the quality of past performance. However, with the possible exceptions of peer reviews for fund allocation and the referee process prior to publication, past quality assurance (QA) activities were primarily informal good practices. This resulted in standards of acceptable practice that varied from organization to organization. The increasing complexity of R ampersand D projects and the increasing need for project results to be upheld outside the scientific community (i.e., lawsuits and licensing hearings) are encouraging R ampersand D organizations and their clients to adopt more formalized methods for the scientific process and to increase control over support organizations (i.e., suppliers and subcontractors). This has become especially true for R ampersand D organizations involved in the high-level (HLW) projects for a number of years. The PNL began to implement QA program requirements within a few HLW repository preliminary studies in 1978. In 1985, PNL developed a comprehensive QA program for R ampersand D activities in support of two of the proposed repository projects. This QA program was developed by the PNL QA department with a significant amount of support assistance and guidance from PNL upper management, the Basalt Waste Isolation Project (BWIP), and the Salt Repository Program Office (SPRO). The QA program has been revised to add a three-level feature and is currently being implemented on projects sponsored by the Office of Geologic Repositories (DOE/OGR), Repository Technology Program (DOE-CH), Nevada Nuclear Waste Storage Investigation (NNWSI) Project, and other HLW projects

  12. Sensitivity of Nuclide Release Behavior to Groundwater Flow in an HLW Repository

    Lee, Youn-Myoung; Hwang, Yong-Soo

    2008-01-01

    Evaluation of the dose exposure rate to human being due to long-term nuclide releases from a high-level waste repository (HLW) is of importance to meet the dose limit presented by the regulatory bodies in order to ensure the performance of a repository. During the last few years, tools by which such a dose rate to an individual can be evaluated have been developed and implemented for a practical calculation to demonstrate the suitability of an HLW repository, with the aid of commercial tools such as AMBER and GoldSim, both of which are capable of probabilistic and deterministic calculations with their convenient user interface. Recently a migration from AMBER based models to GoldSim based ones has been made in accordance with a better feature of GoldSim, which is designed to facilitate the object-oriented modules to address any specialized programs, similar to solving jig saw puzzles and shows more advantage in a detailed complex modeling over AMBER. Recently a compartment modeling approach both for a geosphere and biosphere has been mainly carried out with AMBER in KAERI, which causes a necessity for a newly devised system performance evaluation model in which geosphere and biosphere models could be coupled organically together with less conservatism in the frame of the development of a total system performance assessment modeling tool, which could be successfully done with the aid of GoldSim. Therefore, through the current study, some probabilistic results of the GoldSim approach for a normal situation that could take place in a typical HLW repository are introduced

  13. Influence of the glass particle size on the foaming process and physical characteristics of foam glasses

    König, Jakob; Petersen, Rasmus Rosenlund; Yue, Yuanzheng

    2016-01-01

    We have prepared low-density foam glasses from cathode-ray-tube panel glass using carbon and MnO2 as the foaming agents. The effect of the glass particle size on the foaming process, the apparent density and the pore morphology is revealed. The results show that the foaming is mainly caused...... by the reduction of manganese. Foam glasses with a density of

  14. Bioactive glasses and glass-ceramics

    de Aza, P. N.

    2007-04-01

    Full Text Available Since the late 1960´s, a great interest in the use of bioceramic materials for biomedical applications has been developed. In a previous paper, the authors reviewed crystalline bioceramic materials “sensus stricto”, it is to say, those ceramic materials, constituted for non-metallic inorganic compounds, crystallines and consolidates by thermal treatment of powders at high temperature. In the present review, the authors deal with those called bioactive glasses and glassceramics. Although all of them are also obtained by thermal treatment at high temperature, the first are amorphous and the second are obtained by devitrification of a glass, although the vitreous phase normally prevails on the crystalline phases. After an introduction to the concept of bioactive materials, a short historical review of the bioactive glasses development is made. Its preparation, reactivity in physiological media, mechanism of bonding to living tissues and mechanical strength of the bone-implant interface is also reported. Next, the concept of glass-ceramic and the way of its preparation are exposed. The composition, physicochemical properties and biological behaviour of the principal types of bioactive glasses and glass-ceramic materials: Bioglass®, Ceravital®, Cerabone®, Ilmaplant® and Bioverit® are also reviewed. Finally, a short review on the bioactive-glass coatings and bioactive-composites and most common uses of bioactive-glasses and glass-ceramics are carried out too.

    Desde finales de los años sesenta, se ha despertado un gran interés por el uso de los materiales biocerámicos para aplicaciones biomédicas. En un trabajo previo, los autores hicieron una revisión de los denominados materiales biocerámicos cristalinos en sentido estricto, es decir, de aquellos materiales, constituidos por compuestos inorgánicos no metálicos, cristalinos y consolidados mediante tratamientos térmicos a altas temperaturas. En el presente trabajo, los autores

  15. X-ray tomography of feed-to-glass transition of simulated borosilicate waste glasses

    Harris, William H.; Guillen, Donna P.; Klouzek, Jaroslav; Pokorny, Richard; Yano, Tetsuji

    2017-01-01

    The feed composition of a high level nuclear waste (HLW) glass melter affects the overall melting rate by influencing the chemical, thermophysical, and morphological properties of a relatively insulating cold cap layer over the molten phase where the primary feed vitrification reactions occur. Data from X ray computed tomography imaging of melting pellets comprised of a simulated high-aluminum HLW feed heated at a rate of 10°C/min reveal the distribution and morphology of bubbles, collectively known as primary foam, within this layer for various SiO 2 /(Li 2 CO 3 +H 3 BO 3 +Na 2 CO 3 ) mass fractions at temperatures between 600°C and 1040°C. To track melting dynamics, cross-sections obtained through the central profile of the pellet were digitally segmented into primary foam and a condensed phase. Pellet dimensions were extracted using Photoshop CS6 tools while the DREAM.3D software package was used to calculate pellet profile area, average and maximum bubble areas, and two-dimensional void fraction. The measured linear increase in the pellet area expansion rates – and therefore the increase in batch gas evolution rates – with SiO 2 /(Li 2 CO 3 +H 3 BO 3 +Na 2 CO 3 ) mass fraction despite an exponential increase in viscosity of the final waste glass at 1050°C and a lower total amount of gas-evolving species suggest that the retention of primary foam with large average bubble size at higher temperatures results from faster reaction kinetics rather than increased viscosity. However, viscosity does affect the initial foam collapse temperature by supporting the growth of larger bubbles. Because the maximum bubble size is limited by the pellet dimensions, larger scale studies are needed to understand primary foam morphology at high temperatures. This temperature-dependent morphological data can be used in future investigations to synthetically generate cold cap structures for use in models of heat transfer within a HLW glass melter.

  16. Development of database and QA systems for post closure performance assessment on a potential HLW repository

    Hwang, Y. S.; Kim, S. G.; Kang, C. H.

    2002-01-01

    In TSPA of long-term post closure radiological safety on permanent disposal of HLW in Korea, appropriate management of input and output data through QA is necessary. The robust QA system is developed using the T2R3 principles applicable for five major steps in R and D's. The proposed system is implemented in the web-based system so that all participants in TSRA are able to access the system. In addition, the internet based input database for TSPA is developed. Currently data from literature surveys, domestic laboratory and field experiments as well as expert elicitation are applied for TSPA

  17. The AGP-Project conceptual design for a Spanish HLW final disposal facility

    Biurrun, E.; Engelmann, H.-J.; Huertas, F.; Ulibarri, A.

    1992-01-01

    Within the framework of the AGP Project a Conceptual Design for a HLW Final Disposal Facility to be eventually built in an underground salt formation in Spain has been developed. The AGP Project has the character of a system analysis. In the current project phase I several alternatives has been considered for different subsystems and/or components of the repository. The system variants, developed to such extent as to allow a comparison of their advantages and disadvantages, will allow the selection of a reference concept, which will be further developed to technical maturity in subsequent project phases. (author)

  18. Collaboration, Automation, and Information Management at Hanford High Level Radioactive Waste (HLW) Tank Farms

    Aurah, Mirwaise Y.; Roberts, Mark A.

    2013-01-01

    Washington River Protection Solutions (WRPS), operator of High Level Radioactive Waste (HLW) Tank Farms at the Hanford Site, is taking an over 20-year leap in technology, replacing systems that were monitored with clipboards and obsolete computer systems, as well as solving major operations and maintenance hurdles in the area of process automation and information management. While WRPS is fully compliant with procedures and regulations, the current systems are not integrated and do not share data efficiently, hampering how information is obtained and managed

  19. Chemical durability of borosilicate glasses containing simulated high-level nuclear wastes, 1

    Hara, Shigeo; Terai, Ryohei; Yamanaka, Hiroshi

    1983-01-01

    The Soxhlet-type leaching test apparatus has been developed to evaluate the chemical durability of some borosilicate glasses containing simulated High-Level nuclear Wastes, HLW. After the leaching over the temperature range of 50 0 -95 0 C, the weight loss of specimens with time was determined on both the samples of blocks and grains, and various components dissolved into water were analyzed by atomic absorption and colorimetry technique. It was found that Soxhlet-type test method was more useful than JIS test method, because the specimens in Soxhlet type apparatus were forced always to react with pure water and the mechanism of leaching could be evaluate accurately. The chemical durability of commercial glasses decreases generally with increasing of alkali contents in glasses. In the case of these borosilicate glasses containing HLW, however, the leachability was apparently independent on the alkali contents because of the complexity of these glass compositions. The variation of leaching rate with temperature suggests that dissolution mechanism changes with temperature. (author)

  20. Preparation, structural characterization, and in vitro cell studies of three-dimensional SiO2-CaO binary glass scaffolds built ofultra-small nanofibers.

    Luo, Honglin; Li, Wei; Ao, Haiyong; Li, Gen; Tu, Junpin; Xiong, Guangyao; Zhu, Yong; Wan, Yizao

    2017-07-01

    Three-dimensional (3D) nanofibrous scaffolds hold great promises in tissue engineering and regenerative medicine. In this work, for the first time, 3D SiO 2 -CaO binary glass nanofibrous scaffolds have been fabricated via a combined method of template-assisted sol-gel and calcination by using bacterial cellulose as the template. SEM with EDS, TEM, and AFM confirm that the molar ratio of Ca to Si and fiber diameter of the resultant SiO 2 -CaO nanofibers can be controlled by immersion time in the solution of tetraethyl orthosilicate and ethanol. The optimal immersion time was 6h which produced the SiO 2 -CaO binary glass containing 60at.% Si and 40at.% Ca (named 60S40C). The fiber diameter of 60S40C scaffold is as small as 29nm. In addition, the scaffold has highly porous 3D nanostructure with dominant mesopores at 10.6nm and macropores at 20μm as well as a large BET surface area (240.9m 2 g -1 ), which endow the 60S40C scaffold excellent biocompatibility and high ALP activity as revealed by cell studies using osteoblast cells. These results suggest that the 60S40C scaffold has great potential in bone tissue regeneration. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Study of phase separation and crystallization phenomena in soda-lime borosilicate glass enriched in MoO3

    Magnin, M.

    2009-09-01

    Molybdenum oxide immobilization (MoO 3 , as fission product) is one of the major challenges in the nuclear glass formulation issues for high level waste solutions conditioning since many years, these solutions arising from spent nuclear fuel reprocessing. Phase separation and crystallisation processes may arise in molten glass when the MoO 3 content is higher than its solubility limit that may depend on glass composition. Molybdenum combined with other elements such as alkali and alkaline-earth may form crystalline molybdates, known as 'yellow phases' in nuclear glasses which may decrease the glass durability. In order to confine high level wastes (HLW) such as the fission product solutions arising from the reprocessing of high burn-up UOX-type nuclear spent fuels, a new glass composition (HLW glass) is being optimized. This work is devoted to the study of the origin and the mechanism of phase separation and crystallization phenomena induced by molybdenum oxide incorporation in the HLW glass. From microstructural and structural point of view, the molybdenum oxide behavior was studied in glass compositions belonging to the SiO 2 -B 2 O 3 - Na 2 O-CaO simplified system which constituted basis for the HLW glass formulation. The structural role of molybdenum oxide in borosilicate network explaining the phase separation and crystallization tendency was studied through the coupling of structural ( 95 Mo, 29 Si, 11 B, 23 Na MAS NMR, XRD) and microstructural (SEM, HRTEM) analysis techniques. The determination of phase separation (critical temperature) and crystallization (liquidus temperature) appearance temperatures by in situ viscosimetry and Raman spectroscopy experiments allowed us to propose a transformation scenario during melt cooling. These processes and the nature of the crystalline phases formed (CaMoO 4 , Na 2 MoO 4 ) that depend on the evolution of MoO 3 , CaO and B 2 O 3 contents were correlated with changes of sodium and calcium cations proportions in the

  2. Distributions of 14 elements on 63 absorbers from three simulant solutions (acid-dissolved sludge, acidified supernate, and alkaline supernate) for Hanford HLW Tank 102-SY

    Marsh, S.F.; Svitra, Z.V.; Bowen, S.M.

    1994-08-01

    As part of the Hanford Tank Waste Remediation System program at Los Alamos, we evaluated 63 commercially available or experimental absorber materials for their ability to remove hazardous components from high-level waste (HLW). These absorbers included cation and anion exchange resins, inorganic exchangers, composite absorbers, and a series of liquid extractants sorbed on porous support-beads. We tested these absorbers with three solutions prepared to simulate acid-dissolved sludge (pH 0.6), acidified supernate (pH 3.5), and alkaline supernate (pH 13.9) from underground storage tank 102-SY at the Hanford Reservation near Richland, Washington. To these simulants we added the appropriate radionuclides and used gamma spectrometry to measure fission products (Ce, Cs, Sr, Tc, and Y), actinides (U, Pu, and Am), and matrix elements (Cr, Co, Fe, Mn, Zn, and Zr). For each of more than 2500 element/absorber/solution combinations, we measured distribution coefficients for dynamic contact periods of 30 min, 2 h, and 6 h to obtain information about sorption kinetics. Because we measured the sorption of many different elements, the tabulated results indicate those elements most likely to interfere with the sorption of elements of greater interest. On the basis of nearly 7500 measured distribution coefficients, we determined that many of these absorbers appear suitable for processing HLW. This study supersedes the previous version of LA-12654, in which results attributed to a solution identified as an alkaline supernate simulant were misleading because that solution contained insufficient hydroxide

  3. Chemical analysis of simulated high level waste glasses to support stage III sulfate solubility modeling

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-03-17

    The U.S. Department of Energy (DOE), Office of Environmental Management (EM) is sponsoring an international, collaborative project to develop a fundamental model for sulfate solubility in nuclear waste glass. The solubility of sulfate has a significant impact on the achievable waste loading for nuclear waste forms within the DOE complex. These wastes can contain relatively high concentrations of sulfate, which has low solubility in borosilicate glass. This is a significant issue for low-activity waste (LAW) glass and is projected to have a major impact on the Hanford Tank Waste Treatment and Immobilization Plant (WTP). Sulfate solubility has also been a limiting factor for recent high level waste (HLW) sludge processed at the Savannah River Site (SRS) Defense Waste Processing Facility (DWPF). The low solubility of sulfate in glass, along with melter and off-gas corrosion constraints, dictate that the waste be blended with lower sulfate concentration waste sources or washed to remove sulfate prior to vitrification. The development of enhanced borosilicate glass compositions with improved sulfate solubility will allow for higher waste loadings and accelerate mission completion.The objective of the current scope being pursued by SHU is to mature the sulfate solubility model to the point where it can be used to guide glass composition development for DWPF and WTP, allowing for enhanced waste loadings and waste throughput at these facilities. A series of targeted glass compositions was selected to resolve data gaps in the model and is identified as Stage III. SHU fabricated these glasses and sent samples to SRNL for chemical composition analysis. SHU will use the resulting data to enhance the sulfate solubility model and resolve any deficiencies. In this report, SRNL provides chemical analyses for the Stage III, simulated HLW glasses fabricated by SHU in support of the sulfate solubility model development.

  4. Sealed glass coating of high temperature ceramic superconductors

    Wu, Weite; Chu, Cha Y.; Goretta, Kenneth C.; Routbort, Jules L.

    1995-01-01

    A method and article of manufacture of a lead oxide based glass coating on a high temperature superconductor. The method includes preparing a dispersion of glass powders in a solution, applying the dispersion to the superconductor, drying the dispersion before applying another coating and heating the glass powder dispersion at temperatures below oxygen diffusion onset and above the glass melting point to form a continuous glass coating on the superconductor to establish compressive stresses which enhance the fracture strength of the superconductor.

  5. Review of the effective approaches for providing the R and D information on the geological disposal of HLW

    Mitsuhashi, Hiroshi; Okuhara, Hidehiko; Nanjo, Yuki

    2001-03-01

    Japan Nuclear Cycle Development Institute (JNC) had already carried out Research and development (R and D) activities for the Geological Disposal of High-level Radioactive Waste (HLW) in Japan, the information activities in order to gain a public understanding in Japan. At present, however, the information on the geological disposal project including R and D is still unpopular among the public and does not draw so much attention compared to the other current topics. To make a national consensus on the project, the effective public relational activities with the suitable approaches for the various groups/classes among the public should be done. From the viewpoint of gaining the social recognition, having the valuable interviews with the authorities, opinion leaders and other specialists, we reviewed the approaches of the effective information activities to gain the public attention and let them have proper understanding. We also had some group interviews subject to the university students and housewives, who are expected to have no concern with the geological disposal. During these interviews, we had monitored the degree of understanding on the geological disposal and JNC's R and D activities utilizing the conventional materials that JNC had already prepared, such as brochures and video tape recording, and found if the materials were helpful or not, for proper understanding. A questionnaire survey on the internet was done, as one of yardsticks for the effect of the JNC's activities. We studied the degree of understanding of the respondents, and analyzed the effect of the JNC's public relational activities. Based on the another questionnaire survey results at 'Forum on geological disposal', which was held by JNC, we also analyzed the effect of the forum as one of two-way communications tools. Following the above analysis, the effective approaches of the future public relational activities of the Geological disposal was reviewed. (author)

  6. Crystal Settling, Redox, and High Temperature Properties of ORP HLW and LAW Glasses, VSL-09R1510-1

    Kruger, A. A. [The Catholic Univ. of America, Washington D. C., (United States); Gan, H. [The Catholic Univ. of America, Washington D. C., (United States); Viragh, C. [The Catholic Univ. of America, Washington D. C., (United States); Mckeown, D. A. [The Catholic Univ. of America, Washington D. C., (United States); Muller, I. S. [The Catholic Univ. of America, Washington D. C., (United States); Cecil, R. [The Catholic Univ. of America, Washington D. C., (United States); Kot, W. K. [The Catholic Univ. of America, Washington D. C., (United States); Joseph, I. [EnergySolutions, Laurel, MD (United States); Wang, C. [The Catholic Univ. of America, Washington D. C., (United States); Pegg, I. L. [The Catholic Univ. of America, Washington D. C., (United States); Chaudhuri, M. [The Catholic Univ. of America, Washington D. C., (United States); Zhao, W. [The Catholic Univ. of America, Washington D. C., (United States); Feng, Z. [The Catholic Univ. of America, Washington D. C., (United States)

    2015-06-08

    This report describes the results of testing specified by the Test Plans (VSL-08T1520-1 Rev 0 and VSL-08T1510-1 Rev 0). The work was performed in compliance with the quality assurance requirements specified in the Test Plans. Results required by the Test Plans are reported. The test results and this report have been reviewed for correctness, technical adequacy, completeness, and accuracy.

  7. Simulation of Self-Irradiation of High-Sodium Content Nuclear Waste Glasses

    Pankov, Alexey S.; Ojovan, Michael I.; Batyukhnova, Olga G.; Lee, William E.

    2007-01-01

    Alkali-borosilicate glasses are widely used in nuclear industry as a matrix for immobilisation of hazardous radioactive wastes. Durability or corrosion resistance of these glasses is one of key parameters in waste storage and disposal safety. It is influenced by many factors such as composition of glass and surrounding media, temperature, time and so on. As these glasses contain radioactive elements most of their properties including corrosion resistance are also impacted by self-irradiation. The effect of external gamma-irradiation on the short-term (up to 27 days) dissolution of waste borosilicate glasses at moderate temperatures (30 deg. to 60 deg. C) was studied. The glasses studied were Magnox Waste glass used for immobilisation of HLW in UK, and K-26 glass used in Russia for ILW immobilisation. Glass samples were irradiated under γ-source (Co-60) up to doses 1 and 11 MGy. Normalised rates of elemental release and activation energy of release were measured for Na, Li, Ca, Mg, B, Si and Mo before and after irradiation. Irradiation up to 1 MGy results in increase of leaching rate of almost all elements from both MW and K-26 with the exception of Na release from MW glass. Further irradiation up to a dose of 11 MGy leads to the decrease of elemental release rates to nearly initial value. Another effect of irradiation is increase of activation energies of elemental release. (authors)

  8. Capacity of burning and transmutation reactor and grouping in partitioning of HLW in self-consistent fuel recycle

    Kitamoto, A.; Mulyanto

    1993-01-01

    The concept of capacity of B/T reactor and grouping for partitioning of HLW has been developed in order to perform self-consistent fuel recycle. The concept of grouping of radionuclides is proposed herein, such as Group MA1 (MA below Cm), Group MA2 (Cm and higher MA), Group A ( 99 Te, 129 I, and 135 Cs), Group B ( 137 Cs and 90 Sr) and Group R (the partitioned remain of HLW). In this study P-T treatment were optimized for the in-core and out-core system, respectively. (author). 7 refs., 10 figs

  9. Enhanced sludge processing of HLW: Hydrothermal oxidation of chromium, technetium, and complexants by nitrate. 1998 annual progress report

    Buelow, S.J.; Robinson, J.M.

    1998-01-01

    'The objective of this project is to develop the scientific basis for hydrothermal separation of chromium from High Level Waste (HLW) sludges. The worked is aimed at attaining a fundamental understanding of chromium speciation, oxidation/reduction and dissolution kinetics, reaction mechanisms, and transport properties under hydrothermal conditions in both simple and complex salt solutions that will ultimately lead to an efficient chromium leaching process. This report summarizes the research over the first 1.5 years of a 3 year project. The authors have examined the dissolution of chromium hydroxide using different oxidants as a function of temperature and alkalinity. The results and possible applications to HLW sludges are discussed'

  10. Time evolution of the Clay Barrier Chemistry in a HLW deep geological disposal in granite

    Font, I.; Miguel, M. J.; Juncosa, R.

    2000-01-01

    The main goal of a high level waste geological disposal is to guarantee the waste isolation from the biosphere, locking them away into very deep geological formations. The best way to assure the isolation is by means of a multiple barrier system. These barriers, in a serial disposition, should assure the confinement function of the disposal system. Two kinds of barriers are considered: natural barriers (geological formations) and engineered barriers (waste form, container and backfilling and sealing materials). Bentonite is selected as backfilling and sealing materials for HLW disposal into granite formations, due to its very low permeability and its ability to fill the remaining spaces. bentonite has also other interesting properties, such as, the radionuclide retention capacity by sorption processes. Once the clay barrier has been placed, the saturation process starts. The granite groundwater fills up the voids of the bentonite and because of the chemical interactions, the groundwater chemical composition varies. Near field processes, such as canister corrosion, waste leaching and radionuclide release, strongly depends on the water chemical composition. Bentonite pore water composition is such a very important feature of the disposal system and its determination and its evolution have great relevance in the HLW deep geological disposal performance assessment. The process used for the determination of the clay barrier pore water chemistry temporal evolution, and its influence on the performance assessment, are presented in this paper. (Author)

  11. Proposals of geological sites for L/ILW and HLW repositories. Geological background. Text volume

    2008-01-01

    On April 2008, the Swiss Federal Council approved the conceptual part of the Sectoral Plan for Deep Geological Repositories. The Plan sets out the details of the site selection procedure for geological repositories for low- and intermediate-level waste (L/ILW) and high-level waste (HLW). It specifies that selection of geological siting regions and sites for repositories in Switzerland will be conducted in three stages, the first one (the subject of this report) being the definition of geological siting regions within which the repository projects will be elaborated in more detail in the later stages of the Sectoral Plan. The geoscientific background is based on the one hand on an evaluation of the geological investigations previously carried out by Nagra on deep geological disposal of HLW and L/ILW in Switzerland (investigation programmes in the crystalline basement and Opalinus Clay in Northern Switzerland, investigations of L/ILW sites in the Alps, research in rock laboratories in crystalline rock and clay); on the other hand, new geoscientific studies have also been carried out in connection with the site selection process. Formulation of the siting proposals is conducted in five steps: A) In a first step, the waste inventory is allocated to the L/ILW and HLW repositories; B) The second step involves defining the barrier and safety concepts for the two repositories. With a view to evaluating the geological siting possibilities, quantitative and qualitative guidelines and requirements on the geology are derived on the basis of these concepts. These relate to the time period to be considered, the space requirements for the repository, the properties of the host rock (depth, thickness, lateral extent, hydraulic conductivity), long-term stability, reliability of geological findings and engineering suitability; C) In the third step, the large-scale geological-tectonic situation is assessed and large-scale areas that remain under consideration are defined. For the L

  12. Threshold Assessment: Definition of Acceptable Sites as Part of Site Selection for the Japanese HLW Program

    McKenna, S.A.; Wakasugi, Keiichiro; Webb, E.K.; Makino, Hitoshi; Ishihara, Yoshinao; Ijiri, Yuji; Sawada, Atsushi; Baba, Tomoko; Ishiguro, Katsuhiko; Umeki, Hiroyuki

    2000-01-01

    For the last ten years, the Japanese High-Level Nuclear Waste (HLW) repository program has focused on assessing the feasibility of a basic repository concept, which resulted in the recently published H12 Report. As Japan enters the implementation phase, a new organization must identify, screen and choose potential repository sites. Thus, a rapid mechanism for determining the likelihood of site suitability is critical. The threshold approach, described here, is a simple mechanism for defining the likelihood that a site is suitable given estimates of several critical parameters. We rely on the results of a companion paper, which described a probabilistic performance assessment simulation of the HLW reference case in the H12 report. The most critical two or three input parameters are plotted against each other and treated as spatial variables. Geostatistics is used to interpret the spatial correlation, which in turn is used to simulate multiple realizations of the parameter value maps. By combining an array of realizations, we can look at the probability that a given site, as represented by estimates of this combination of parameters, would be good host for a repository site

  13. Natural analogues for containment-providing barriers for a HLW repository in salt

    Wolf, J.; Noseck, U.

    2015-06-15

    In 2005, a German research project was started to develop a novel approach to prove safety for a HLW repository in a salt formation, to refine the safety concept, to identify open scientific issues and to define necessary R&D work. This project aimed at identifying the key information for a HLW repository in salt. One important question is how this information may be best fulfilled by natural analogue studies. This question is answered by starting a review of the required key information needs of the safety case (post-closure phase) in order to assess whether or not these requirements can be supported by natural analogues information. In order to structure the review and to address the key elements of the safety concepts, three types of natural analogues are distinguished: (i) natural analogues for the integrity of the geological barrier, (ii) natural analogues for the integrity of the geotechnical barriers and (iii) natural analogues for release scenarios. For the safety case in salt type (i) and (ii) are of highest importance and are treated in this paper. The assessment documented in this paper on the one hand indicates the high potential benefit of natural analogues for a safety case in salt and on the other hand helps to focus the available human and financial resources for the safety case on the most safety-relevant aspects. (authors)

  14. Status of the safety concept and safety demonstration for an HLW repository in salt. Summary report

    Bollingerfehr, W.; Buhmann, D.; Filbert, W.; and others

    2013-12-15

    Salt formations have been the preferred option as host rocks for the disposal of high level radioactive waste in Germany for more than 40 years. During this period comprehensive geological investigations have been carried out together with a broad spectrum of concept and safety related R and D work. The behaviour of an HLW repository in salt formations, particularly in salt domes, has been analysed in terms of assessment of the total system performance. This was first carried out for concepts of generic waste repositories in salt and, since 1998, for a repository concept with specific boundary conditions, taking the geology of the Gorleben salt dome as an example. Suitable repository concepts and designs were developed, the technical feasibility has been proven and operational and long-term safety evaluated. Numerical modelling is an important input into the development of a comprehensive safety case for a waste repository. Significant progress in the development of numerical tools and their application for long-term safety assessment has been made in the last two decades. An integrated approach has been used in which the repository concept and relevant scientific and engineering data are combined with the results from iterative safety assessments to increase the clarity and the traceability of the evaluation. A safety concept that takes full credit of the favourable properties of salt formations was developed in the course of the R and D project ISIBEL, which started in 2005. This concept is based on the safe containment of radioactive waste in a specific part of the host rock formation, termed the containment providing rock zone, which comprises the geological barrier, the geotechnical barriers and the compacted backfill. The future evolution of the repository system will be analysed using a catalogue of Features, Events and Processes (FEP), scenario development and numerical analysis, all of which are adapted to suit the safety concept. Key elements of the

  15. Preparation and magnetic properties of magnetic photonic crystal by using monodisperse polystyrene covered Fe3O4 nanoparticles onto glass substrate

    Azizi, Zahra Sadat; Tehranchi, Mohammad Mehdi; Vakili, Seyed Hamed; Pourmahdian, Saeed

    2018-05-01

    Engineering approach towards combined photonic band gap properties and magnetic/polymer composite particles, attract considerable attention of researchers due to their unique properties. In this research, two different magnetic particles were prepared by nearly monodisperse polystyrene spheres as bead with two concentrations of Fe3O4 nanoparticles to prepare magnetic photonic crystals (MPCs). The crystal surfaces and particles morphology were investigated employing scanning electron microscopy and transmission electron microscopy. The volume fraction of magnetic material embedded into colloidal spheres and their morphology was found to be a key parameter in the optical and magneto-optical properties of transparent MPC.

  16. Incorporating Cold Cap Behavior in a Joule-heated Waste Glass Melter Model

    Varija Agarwal; Donna Post Guillen

    2013-08-01

    In this paper, an overview of Joule-heated waste glass melters used in the vitrification of high level waste (HLW) is presented, with a focus on the cold cap region. This region, in which feed-to-glass conversion reactions occur, is critical in determining the melting properties of any given glass melter. An existing 1D computer model of the cold cap, implemented in MATLAB, is described in detail. This model is a standalone model that calculates cold cap properties based on boundary conditions at the top and bottom of the cold cap. Efforts to couple this cold cap model with a 3D STAR-CCM+ model of a Joule-heated melter are then described. The coupling is being implemented in ModelCenter, a software integration tool. The ultimate goal of this model is to guide the specification of melter parameters that optimize glass quality and production rate.

  17. Proposal for geological site selection for L/ILW and HLW repositories. Statement of requirements, procedure and results. Technical report 08-03

    2008-10-01

    Important steps in the process of managing radioactive wastes have already been implemented in Switzerland. These include the handing and packaging of the waste, waste characterisation and documentation of waste inventories and interim storage along with associated transport. In terms of preparing for deep geological disposal, the necessary scientific and technical work is well advanced and the feasibility of constructing geological repositories that provide the required long-term safety has been successfully demonstrated for all waste types arising in Switzerland. Sufficient knowledge is available to allow the next steps in the selection of repository sites to be defined. The legal framework is also in place and organisational measures have been provided that will allow the tasks to be performed in the coming years to be implemented efficiently. The selection of geological siting regions and sites for repositories in Switzerland will be conducted in three stages. Stage 1 ends with the definition of geological siting regions within which the repository projects will be elaborated in more detail in stages 2 and 3. This report documents and justifies the siting proposals prepared by Nagra for the repositories for low- and intermediate-level waste (L/ILW) and high-level waste (HLW). Formulation of these proposals is conducted in five steps: 1) The waste inventory, which includes reserves for future developments, is allocated to the L/ILW and HLW repositories; 2) Based on this waste allocation, the second step involves defining the barrier and safety concepts for the two repositories. With a view to evaluating the geological siting possibilities, quantitative and qualitative guidelines and requirements on the geology are derived on the basis of these concepts. These relate to the time period to be considered, the space requirements for the repository, the properties of the host rock (depth, thickness, lateral extent, hydraulic conductivity), long-term stability

  18. Chemical durability of lead borosilicate glass matrix under simulated geological conditions

    Yalmali, Vrunda S.; Deshingkar, D.S.; Wattal, P.K.

    2002-03-01

    The lead borosilicate glass has been developed for vitrification of High Level Waste (HLW) stored at Trombay. This waste is contains especially high contents of sodium, uranium sulphate and iron. The glasses containing HLW are to be ultimately disposed into deep geological repositories. Long term leach rates under simulated geological conditions need to be evaluated for glass matrix. Studies were taken up to estimate the lead borosilicate glass WTR-62 matrix for chemical durability in presence of synthetic ground water. The leachant selected was based on composition of ground water sample near proposed repository site. In the first phase of these tests, the experiments were conducted for short duration of one and half month. The leaching experiments were conducted in presence of a) distilled water b) synthetic ground water c) synthetic ground water containing granite, bentonite and ferric oxide and d) synthetic ground water containing humic acid at 100 0 C. The leachate samples were analysed by pHmetry , ion chromatography and UV -VIS spectrophotometry. The normalised leach rates for lead borosilicate WTR- 62 glass matrix based on silica, boron and sulphate analyses of leachates were of the order of 10 -3 to 10 -5 gms/cm 2 /day for 45 days test period in presence of synthetic ground water as well as in presence of other materials likely to be present along with synthetic ground water. These rates are comparable to those of sodium borsilicate glass matrices reported in literature. It is known that the leach rates of glass matrix decrease with longer test durations due to formation of leached layer on its surface. The observed leach rates of lead borosilicate WTR- 62 glass matrix for 45 day tests under simulated geological conditions were found to be sufficiently encouraging to take up long term tests for evaluating its performances under repository conditions. (author)

  19. Final Report Integrated DM1200 Melter Testing Of Bubbler Configurations Using HLW AZ-101 Simulants VSL-04R4800-4, Rev. 0, 10/5/04

    Kruger, A.A.; Matlack, K.S.; Gong, W.; Bardakci, T.; D'Angelo, N.A.; Lutze, W.; Callow, R.A.; Brandys, M.; Kot, W.K.; Pegg, I.L.

    2011-01-01

    This report documents melter and off-gas performance results obtained on the DM1200 HLW Pilot Melter during processing of AZ-101 HLW simulants. The tests reported herein are a subset of six tests from a larger series of tests described in the Test Plan for the work; results from the other tests have been reported separately. The solids contents of the melter feeds were based on the WTP baseline value for the solids content of the feeds from pretreatment which changed during these tests from 20% to 15% undissolved solids resulting in tests conducted at two feed solids contents. Based on the results of earlier tests with single outlet 'J' bubblers, initial tests were performed with a total bubbling rate of 651 pm. The first set of tests (Tests 1A-1E) addressed the effects of skewing this total air flow rate back and forth between the two installed bubblers in comparison to a fixed equal division of flow between them. The second set of tests (2A-2D) addressed the effects of bubbler depth. Subsequently, as the location, type and number of bubbling outlets were varied, the optimum bubbling rate for each was determined. A third (3A-3C) and fourth (8A-8C) set of tests evaluated the effects of alternative bubbler designs with two gas outlets per bubbler instead of one by placing four bubblers in positions simulating multiple-outlet bubblers. Data from the simulated multiple outlet bubblers were used to design bubblers with two outlets for an additional set of tests (9A-9C). Test 9 was also used to determine the effect of small sugar additions to the feed on ruthenium volatility. Another set of tests (10A-10D) evaluated the effects on production rate of spiking the feed with chloride and sulfate. Variables held constant to the extent possible included melt temperature, plenum temperature, cold cap coverage, the waste simulant composition, and the target glass composition. The feed rate was increased to the point that a constant, essentially complete, cold cap was achieved

  20. FINAL REPORT INTEGRATED DM1200 MELTER TESTING OF BUBBLER CONFIGURATIONS USING HLW AZ-101 SIMULANTS VSL-04R4800-4 REV 0 10/5/04

    KRUGER AA; MATLACK KS; GONG W; BARDAKCI T; D' ANGELO NA; LUTZE W; CALLOW RA; BRANDYS M; KOT WK; PEGG IL

    2011-12-29

    This report documents melter and off-gas performance results obtained on the DM1200 HLW Pilot Melter during processing of AZ-101 HLW simulants. The tests reported herein are a subset of six tests from a larger series of tests described in the Test Plan for the work; results from the other tests have been reported separately. The solids contents of the melter feeds were based on the WTP baseline value for the solids content of the feeds from pretreatment which changed during these tests from 20% to 15% undissolved solids resulting in tests conducted at two feed solids contents. Based on the results of earlier tests with single outlet 'J' bubblers, initial tests were performed with a total bubbling rate of 651 pm. The first set of tests (Tests 1A-1E) addressed the effects of skewing this total air flow rate back and forth between the two installed bubblers in comparison to a fixed equal division of flow between them. The second set of tests (2A-2D) addressed the effects of bubbler depth. Subsequently, as the location, type and number of bubbling outlets were varied, the optimum bubbling rate for each was determined. A third (3A-3C) and fourth (8A-8C) set of tests evaluated the effects of alternative bubbler designs with two gas outlets per bubbler instead of one by placing four bubblers in positions simulating multiple-outlet bubblers. Data from the simulated multiple outlet bubblers were used to design bubblers with two outlets for an additional set of tests (9A-9C). Test 9 was also used to determine the effect of small sugar additions to the feed on ruthenium volatility. Another set of tests (10A-10D) evaluated the effects on production rate of spiking the feed with chloride and sulfate. Variables held constant to the extent possible included melt temperature, plenum temperature, cold cap coverage, the waste simulant composition, and the target glass composition. The feed rate was increased to the point that a constant, essentially complete, cold cap was

  1. BNFL Report Glass Formers Characterization

    Schumacher, R.F.

    2000-07-27

    The objective of this task was to obtain powder property data on candidate glass former materials, sufficient to guide conceptual design and estimate the cost of glass former handling facilities as requested under Part B1 of BNFL Technical and Development Support. Twenty-nine glass forming materials were selected and obtained from vendors for the characterization of their physical properties, durability in caustic solution, and powder flow characteristics. A glass former was selected based on the characterization for each of the ten oxide classes required for Envelope A, B, and C mixtures. Three blends (A, B, and C) were prepared based on formulations provided by Vitreous State Laboratory and evaluated with the same methods employed for the glass formers. The properties obtained are presented in a series of attached Tables. It was determined that five of the ten glass formers, (kyanite, iron oxide, titania, zircon, and zinc oxide) have the potential to cause some level of solids f low problems. In addition, all of the blends may require consideration for their handling. A number of engineering considerations and recommendations were prepared based on the experimental findings, experience, and other process considerations. Recommendations for future testing are included. In conjunction with future work, it is recommended that a professional consultant be engaged to guide and assist with testing and design input.

  2. BNFL Report Glass Formers Characterization

    Schumacher, R.F.

    2000-01-01

    The objective of this task was to obtain powder property data on candidate glass former materials, sufficient to guide conceptual design and estimate the cost of glass former handling facilities as requested under Part B1 of BNFL Technical and Development Support. Twenty-nine glass forming materials were selected and obtained from vendors for the characterization of their physical properties, durability in caustic solution, and powder flow characteristics. A glass former was selected based on the characterization for each of the ten oxide classes required for Envelope A, B, and C mixtures. Three blends (A, B, and C) were prepared based on formulations provided by Vitreous State Laboratory and evaluated with the same methods employed for the glass formers. The properties obtained are presented in a series of attached Tables. It was determined that five of the ten glass formers, (kyanite, iron oxide, titania, zircon, and zinc oxide) have the potential to cause some level of solids f low problems. In addition, all of the blends may require consideration for their handling. A number of engineering considerations and recommendations were prepared based on the experimental findings, experience, and other process considerations. Recommendations for future testing are included. In conjunction with future work, it is recommended that a professional consultant be engaged to guide and assist with testing and design input

  3. The influence of glass composition on crystalline phase stability in glass-ceramic wasteforms

    Maddrell, Ewan; Thornber, Stephanie; Hyatt, Neil C.

    2015-01-01

    Highlights: • Crystalline phase formation shown to depend on glass matrix composition. • Zirconolite forms as the sole crystalline phase only for most aluminous glasses. • Thermodynamics indicate that low silica activity glasses stabilise zirconolite. - Abstract: Zirconolite glass-ceramic wasteforms were prepared using a suite of Na 2 O–Al 2 O 3 –B 2 O 3 –SiO 2 glass matrices with variable Al:B ratios. Zirconolite was the dominant crystalline phase only for the most alumina rich glass compositions. As the Al:B ratio decreased zirconolite was replaced by sphene, zircon and rutile. Thermodynamic data were used to calculate a silica activity in the glass melt below which zirconolite is the favoured crystalline phase. The concept of the crystalline reference state of glass melts is then utilised to provide a physical basis for why silica activity varies with the Al:B ratio

  4. Qualification and characterization programmes for disposal of a glass product resulting from high level waste vitrification in the PAMELA installation of BELGOPROCESS

    Goeyse, A. de; De, A.K.; Demonie, M.; Iseghem, P. van

    1993-01-01

    In the framework of a general quality assurance and quality control (QA/QC) programme, the quality of a conditioned waste product is achieved in two phases. The first phase is the design of a process and facility which will ensure the required quality of the product. In the second phase the conformance of the product with the preset requirements is verified. NIRAS/ONDRAF, as the agency responsible for the management of all radioactive waste in Belgium (including treatment, conditioning, storage and disposal), controls compliance with the quality requirements during both phases. The purpose of the paper is to describe the different phases of this general procedure in the case of a vitrified HLW product resulting from a vitrification campaign in the PAMELA facility at the BELGOPROCESS site. The active glass product of type SM527 produced during the vitrification of highly enriched waste concentrate (HEWC) (resulting from the reprocessing of highly enriched uranium fuel) has been selected for illustration. During the process qualification phase, the Deutsche Gesellschaft fuer Wiederaufarbeitung von Kernbrennstoffen mbH, responsible for the development of the vitrification process of PAMELA, defined and performed and R and D programmed for each glass product originating from the vitrification of the different HEWC solutions stored at the BELGOPROCESS site. At the end of this qualification phase a data catalogue was prepared. In order to ensure that the active glass product corresponds with the selected product from the data catalogue, the QA/QC handbook for the vitrification process describes all measures to be taken by the waste producer, BELGOPROCESS, during the vitrification. Finally, verification analyses are performed by the characterization of inactive and active samples by an independent laboratory. This phase is called the product quality verification phase. The details of the characterization programmes performed during the different phases and their results

  5. Effects of a Capital Investment and a Discount Rate on the Optimal Operational Duration of an HLW Repository

    Kim, Sung Ki; Lee, Min Soo; Choi, Heui Joo; Choi, Jong Won

    2008-01-01

    This study aims to estimate the effects of a capital investment and a discount rate on the optimal operational duration of an HLW repository. According to the previous researches of the KRS(Korea Reference System) for an HLW repository, the amounts of 7,068,200 C$K and 2,636.2 MEUR are necessary to construct and operate surface and underground facilities. Since these huge costs can be a burden to some national economies, a study for a cost optimization should be performed. So we aim to drive the dominant cost driver for an optimal operational duration. A longer operational duration may be needed to dispose of more spent fuels continuously from a nuclear power plant, or to attain a retrievability of an HLW repository at a depth of 500 m below the ground level in a stable plutonic rock body. In this sense, an extended operational duration for an HLW repository affects the overall disposal costs of a repository. In this paper, only the influence of a capital investment and a discount rate was estimated from the view of optimized economics. Because these effects must be significant factors to minimize the overall disposal costs based on minimizing the sum of operational costs and capital investments

  6. Study on systematic integration technology of design and safety assessment for HLW geological disposal. 2. Research document

    Ishihara, Yoshinao; Fukui, Hiroshi; Sagawa, Hiroshi; Matsunaga, Kenichi; Ito, Takaya; Kohanawa, Osamu; Kuwayama, Yuki

    2003-02-01

    The present study was carried out relating to basic design of the Geological Disposal Technology Integration System' that will be systematized as knowledge base for design analysis and safety assessment of HLW geological disposal system by integrating organically and hierarchically various technical information in three study field. The key conclusions are summarized as follows: (1) As referring to the current performance assessment report, the technical information for R and D program of HLW geological disposal system was systematized hierarchically based on summarized information in a suitable form between the work flow (work item) and processes/characteristic flow (process item). (2) As the result of the systematized technical information, database structure and system functions necessary for development and construction to the computer system were clarified in order to secure the relation between technical information and data set for assessment of HLW geological disposal system. (3) The control procedure for execution of various analysis code used by design and safety assessment in HLW geological disposal study was arranged possibility in construction of 'Geological Disposal Technology Integration System' after investigating the distributed computing technology. (author)

  7. Safety case development in the Japanese programme for geological disposal of HLW: Evolution in the generic stage

    Ueda, Hiroyoshi; Ishiguro, Katsuhiko; Takeuchi, Mitsuo; Fujihara, Hiroshi; Takeda, Seietsu

    2014-01-01

    In the Japanese programme for nuclear power generation, the safe management of the resulting radioactive waste, particularly vitrified high-level waste (HLW) from fuel reprocessing, has been a major concern and a focus of R and D since the late 70's. According to the specifications in a report issued by an advisory committee of the Japan Atomic Energy Commission (JAEC, 1997), the Second Progress Report on R and D for the Geological Disposal of HLW (H12 report) (JNC, 2000) was published after two decades of R and D activities and showed that disposal of HLW in Japan is feasible and can be practically implemented at sites which meet certain geological stability requirements. The H12 report supported government decisions that formed the basis of the 'Act on Final Disposal of Specified Radioactive Waste' (Final Disposal Act), which came into force in 2000. The Act specifies deep geological disposal of HLW at depths greater than 300 metres, together with a stepwise site selection process in three stages. Following the Final Disposal Act, the supporting 'Basic Policy for Final Disposal' and the 'Final Disposal Plan' were authorised in the same year. (authors)

  8. Breaking the glass ceiling.

    Lazarus, A

    1997-03-01

    The glass ceiling is a form of organizational bias and discrimination that prevents qualified professionals from achieving positions of top governance and leadership. This article examines glass ceiling barriers that keep physicians from the upper reaches of management. While these factors apply mainly to women and minority physicians in academia, and are attributable to sexual harassment and discrimination, physicians as a class are frequently denied executive management positions. Such denial results from inadequate preparation for a career in health care administration. Important issues in the professional development of physician executives include mentoring, training and education, administrative experience, and cultural and personality factors. All of those must be considered when making the transition from medicine to management.

  9. Glass ceramic seals to inconel

    McCollister, Howard L.; Reed, Scott T.

    1983-11-08

    A glass ceramic composition prepared by subjecting a glass composition comprising, by weight, 65-80% SiO.sub.2, 8-16%, Li.sub.2 O, 2-8% , Al.sub.2 O.sub.3, 1-8% K.sub.2 O, 1-5% P.sub.2 O.sub.5 and 1.5-7% B.sub.2 O.sub.3, to the following processing steps of heating the glass composition to a temperature sufficient to crystallize lithium metasilicate therein, holding the glass composition at a temperature and for a time period sufficient to dissolve the lithium metasilicate therein thereby creating cristobalite nucleii, cooling the glass composition and maintaining the composition at a temperature and for a time period sufficient to recrystallize lithium metasilicate therein, and thermally treating the glass composition at a temperature and for a time period sufficient to cause growth of cristobalite and further crystallization of lithium metasilicate producing a glass ceramic composition having a specific thermal expansion coefficient and products containing said composition.

  10. Wastes based glasses and glass-ceramics

    Barbieri, L.

    2001-12-01

    Full Text Available Actually, the inertization, recovery and valorisation of the wastes coming from municipal and industrial processes are the most important goals from the environmental and economical point of view. An alternative technology capable to overcome the problem of the dishomogeneity of the raw material chemical composition is the vitrification process that is able to increase the homogeneity and the constancy of the chemical composition of the system and to modulate the properties in order to address the reutilization of the waste. Moreover, the glasses obtained subjected to different controlled thermal treatments, can be transformed in semy-cristalline material (named glass-ceramics with improved properties with respect to the parent amorphous materials. In this review the tailoring, preparation and characterization of glasses and glass-ceramics obtained starting from municipal incinerator grate ash, coal and steel fly ashes and glass cullet are described.

    Realmente la inertización, recuperación y valorización de residuos que proceden de los procesos de incineración de residuos municipales y de residuos industriales son metas importantes desde el punto de vista ambiental y económico. Una tecnología alternativa capaz de superar el problema de la heterogeneidad de la composición química de los materiales de partida es el proceso de la vitrificación que es capaz de aumentar la homogeneidad y la constancia de la composición química del sistema y modular las propiedades a fin de la reutilización del residuo. En este artículo se presentan los resultados de vitrificación en que los vidrios fueron sometidos a tratamientos térmicos controlados diferentes, de manera que se transforman en materiales semicristalinos (también denominados vitrocerámicos con mejores propiedades respecto a los materiales amorfos originales. En esta revisión se muestra el diseño, preparación y caracterización de vidrios y vitrocerámicos partiendo de

  11. Glass-Graphite Composite Materials

    Mayzan, M.Z.H.; Lloyd, J.W.; Heath, P.G.; Stennett, M.C.; Hyatt, N.C.; Hand, R.J.

    2016-01-01

    A summary is presented of investigations into the potential of producing glass-composite materials for the immobilisation of graphite or other carbonaceous materials arising from nuclear power generation. The methods are primarily based on the production of base glasses which are subsequently sintered with powdered graphite or simulant TRISO particles. Consideration is also given to the direct preparation of glass-graphite composite materials using microwave technology. Production of dense composite wasteforms with TRISO particles was more successful than with powdered graphite, as wasteforms containing larger amounts of graphite were resistant to densification and the glasses tried did not penetrate the pores under the pressureless conditions used. Based on the results obtained it is concluded that the production of dense glassgraphite composite wasteforms will require the application of pressure. (author)

  12. A comparative evaluation of the retention of metallic brackets bonded with resin-modified glass ionomer cement under different enamel preparations: A pilot study

    Padmaja Sharma

    2013-01-01

    Full Text Available Introduction: For orthodontists, the ideal bonding material should be less moisture-sensitive and should release fluoride, thereby reducing unfavorable iatrogenic decalcification. Resin-Modified Glass Ionomer Cements (RMGICs, due to their ability to bond in the presence of saliva and blood can be a very good bonding agent for orthodontic attachments especially in the areas of mouth, which are difficult to access. Moreover, their fluoride releasing property makes them an ideal bonding agent for patients with poor oral hygiene. However, their immediate bond strength is said to be too low to immediately ligate the initial wire, which could increase the total number of appointments. The effect of sandblasting and the use of sodium hypochlorite (NaOCL on the immediate bond failure of RMGIC clinically have not been reported in the literature until the date. This investigation intended to assess the effect of sandblasting (of the bracket base and enamel and NaOCL on the rate of bond failure (with immediate ligation at 30 min of Fuji Ortho LC and its comparison with that of conventional light cured composite resin over a period of 1 year. Materials and Methods: 400 sample teeth were further divided into 4 groups of 100 each and bonded as follows: (1 Group 1: Normal metallic brackets bonded with Fuji Ortho LC. (2 Group 2: Sandblasted bracket base and enamel surface, brackets bonded with Fuji Ortho LC. (3 Group 3: Deproteinized enamel surface using sodium hypochlorite and brackets bonded with Fuji Ortho LC. (4 Group 4: Normal metallic bracket bonded with Transbond XT after etching enamel with 37% phosphoric acid. This group served as control group. Results and Conclusion: Results showed that sandblasting the bracket base and enamel, can significantly reduce the bond failure rate of RMGIC.

  13. Influence of processing conditions on the glass-crystal transition into borosilicate glasses

    Deschanels, X.; Cachia, J.N.; Lopez, C.; Peuget, S. [CEA Marcoule, BP 17171, 30207 Bagnols sur Ceze (France)

    2008-07-01

    The precipitation of a crystalline phase in glass is observed when one element exceeds its loading limit (i.e.: solubility limit). In this work we have studied the solubility of different actinides and surrogates (lanthanides and hafnium) in borosilicate glass used for the immobilization of the high-level nuclear waste (HLW glasses). The results obtained show an increase of the solubility limits of these elements with the processing temperature and the redox potential of the melt. The elements at the oxidation state (III) exhibit a higher solubility than the element at oxidation state (IV). In this framework, cerium is an interesting element because its oxidation state tunes from (IV) to (III) as a function of the processing conditions. It is shown that the solubility of cerium can be multiplied by a factor of 20 at 1100 C. degrees. In order to have a better understanding of the mechanisms that underline the evolution of the solubility, XAFS and NMR investigation has been undertaken. Trivalent elements present the characteristics of network-modified cations while tetravalent elements look like network-former cations.

  14. Investigations on vanadium doped glasses

    Madhusudana Rao, P.

    2013-01-01

    The glass samples studied in the present work have been prepared by melt quenching technique. They were prepared by mixing and grinding together by appropriate amounts of Li 2 O - Na 2 O - B 2 O 3 doped with V 2 O 5 in an agate motor before transferring into crucible. The mixtures were heated in an electric furnace at 1225K for 20 mm. The melt was then quenched to room temperature by pouring it on plane brass plate and pressing it with another brass plate. White and yellow coloured glasses have been obtained with good optical quality and high transparency. Finally the vitreous sample were annealed for 3 hrs at 423K to relieve residual internal stress and slowly cooled to room temperature. The polished glasses have been used for XRD, FTIR analysis and for DSC report. The DSC thermo grams for all the glasses were recorded on in the temperature range 50-550℃ with a heating rate of 10℃/min. Electron spin resonance and optical absorption of 20Li 2 O - 10 Na 2 O - (70-X)B 2 O 3 doped with XV 2 O 5 glass system are studied. ESR spectra of V 4+ ions doped in the glass exhibit peak at g =1.98. Spin Hamiltonian parameters are calculated. It was found that these parameters are dependent upon alkali ion concentration in the glass and the VO +2 ion in an octahedral coordination with a tetragonal compression. The physical parameters of all glasses were also evaluated with respect to the composition

  15. Glass: Rotary Electric Glass Furnace

    Recca, L.

    1999-01-29

    Compared to conventional gas-fired furnaces, the new rotary electric furnace will increase energy efficiency while significantly reducing air emissions, product turnaround time, and labor costs. As this informative new fact sheet explains, the thousand different types of glass optical blanks produced for the photonics industry are used for lasers, telescopes, cameras, lights, and many other products.

  16. Proceedings: EPRI Workshop 2 -- Technical basis for EPA HLW disposal criteria

    Rogers, V.

    1993-03-01

    The Electric Power Research Institute (EPRI) sponsored this workshop to address the scientific and technical issues underlying the regulatory criteria, or standard, for the disposal of spent nuclear fuel, high-level radioactive waste, and transuranic waste, commonly referred to collectively as high-level waste (HLW). These regulatory criteria were originally promulgated by the US Environmental Protection Agency (EPA) in 40 CFR Part 191 in 1985. However, significant portions of the regulation were remanded by the Ninth Circuit Court of Appeals in 1987. This is the second of two workshops. Topics discussed include: gas pathway; individual and groundwater protection; human intrusion; population protection; performance; TRU conversion factors and discussions. Individual projects re processed separately for the databases

  17. KAERI Underground Research Facility (KURF) for the Demonstration of HLW Disposal Technology

    Hahn, P. S.; Cho, W. J.; Kwon, S.

    2006-01-01

    In order to dispose of high-level radioactive waste(HLW) safely in geological formations, it is necessary to assess the feasibility, safety, appropriateness, and stability of the disposal concept at an underground research site, which is constructed in the same geological formation as the host rock. In this paper, the current status of the conceptual design and the construction of a small scale URL, which is named as KURF, were described. To confirm the validity of the conceptual design of the underground facility, a geological survey including a seismic refraction survey, an electronic resistivity survey, a borehole drilling, and in situ and laboratory tests had been carried out. Based on the site characterization results, it was possible to effectively design the KURF. The construction of the KURF was started in May 2005 and the access tunnel was successfully completed in March 2006. Now the construction of the research modules is under way

  18. Role of international collaboration in PNC's R ampersand D programme for HLW disposal

    Masuda, Sumio; Umeki, Hiroyuki; Yamakawa, Minoru

    1996-01-01

    PNC has been active in promoting international cooperation in connection with the Japanese HLW disposal programme, based on both a bilateral and multilateral approach. Both types of cooperation are extremely useful; in particular, bilateral cooperation has the advantage of providing opportunities for in-depth discussions in mutual areas of interest. By way of contrast, multilateral cooperation also provides an international arena for broader discussion and corroboration of output from individual R ampersand D programmes. International collaboration also provides young researchers with an opportunity to learn from experience. Depending on the issues to be tackled, appropriate forms of collaboration have been integrated into PNC's strategy for maximizing output. The lessons learned from collaboration are very valuable and can be used directly in their programme to enhance its credibility. The format of collaboration has also been extensively developed: it has been found that resources can be utilized more effectively by sharing them appropriately

  19. Depth optimization for the Korean HLW repository System within a discontinuous and saturated granitic rock mass

    Kim, Jhin Wung; Bae, Dae Seok; Choi, Jong Won

    2005-12-01

    The present study is to evaluate the material properties of the compacted bentonite, backfill material, canister cast iron insert, and the rock mass for the Korean HLW repository system. These material properties are either measured, or taken from other countries, through the evaluation of the thermal, hydraulic, and mechanical interaction behavior of a repository. After the evaluation of the material properties, the most appropriate and economical depth as well as the layout of a single layer repository is to be recommended. Material properties used for the granitic rock mass, rock joints, PWR spent fuel, disposal canister, compacted bentonite, backfill material, and ground water are the data collected domestically, and foreign data are used for some of the data not available domestically. The repository model includes a saturated granitic rock mass with joints, PWR spent fuel in a disposal canister surrounded by compacted bentonite inside a deposition hole, and backfill material in the rest of the space within a repository cavern

  20. Technical Standards on the Safety Assessment of a HLW Repository in Other Countries

    Lee, Sung Ho; Hwang, Yong Soo

    2009-01-01

    The basic function of HLW disposal system is to prevent excessive radio-nuclides being leaked from the repository in a short time. To do this, many technical standards should be developed and established on the components of disposal system. Safety assessment of a repository is considered as one of technical standards, because it produces quantitative results of the future evolution of a repository based on a reasonably simplified model. In this paper, we investigated other countries' regulations related to safely assessment focused on the assessment period, radiation dose limits and uncertainties of the assessment. Especially, in the investigation process of the USA regulations, the USA regulatory bodies' approach to assessment period and peak dose is worth taking into account in case of a conflict between peak dose from safety assessment and limited value in regulation.