Liquidus Temperature and Primary Crystallization Phases in High-Zirconia High-Level Waste Borosilicate Glasses

1999 ◽  
Vol 608 ◽  
Author(s):  
Trevor Plaisted ◽  
Pavel Hrma ◽  
John Vienna ◽  
Antonin Jiricka
Keyword(s):  
Liquidus Temperature ◽  
Primary Crystallization ◽  
High Level Waste ◽  
Borosilicate Glasses ◽  
High Level

Liquidus Temperature of High-Level Waste Borosilicate Glasses With Spinel Primary Phase

1999 ◽  
Vol 608 ◽  
Author(s):  
Pavel Hrma ◽  
John Vienna ◽  
Jarrod Crum ◽  
Greg Piepel ◽  
Martin Mika
Keyword(s):  
Liquidus Temperature ◽  
Primary Phase ◽  
High Level Waste ◽  
Borosilicate Glasses ◽  
High Level

Liquidus Temperature of Spinel Precipitating High-Level Waste Glasses

1996 ◽  
Vol 465 ◽  
Author(s):  
M. Mika ◽  
M. J. Schweiger ◽  
J. D. Vienna ◽  
P. Hrma
Keyword(s):  
Mixture Models ◽  
Crystalline Phase ◽  
Liquidus Temperature ◽  
Glass Composition ◽  
High Level Waste ◽  
Hanford Site ◽  
High Iron ◽  
Negative Effect ◽  
High Level ◽  
Glass Viscosity

ABSTRACTThe liquidus temperature (TL) often limits the loading of high-level waste in glass through the constraint that TL must be at least 100°C below the temperature at which the glass viscosity is 5 Pa-s. In this study, values of TL for spinel primary crystalline phase were measured as a function of glass composition. The test glasses were based on high-iron Hanford Site tank wastes. All studied glasses precipitated spinel (Ni,Fe,Mn)(Cr,Fe)2O4 as the primary crystalline phase. TL was increased by additions of Cr2O3, NiO, Al2O3, Fe2O3, MgO, and MnO; while Li2O, Na2O, B2O3, and SiO2 had a negative effect. Empirical mixture models were fitted to data.

Spinel Settling in HLW Melters

2001 ◽  
Author(s):  
Josef Matyáš ◽  
Jaroslav Kloužek ◽  
Lubomír Němec ◽  
Miroslav Trochta
Keyword(s):  
Liquidus Temperature ◽  
Linear Growth ◽  
Critical Level ◽  
High Level Waste ◽  
Input Concentration ◽  
Average Temperature ◽  
Input Size ◽  
Waste Loading ◽  
High Level ◽  
The Impact

Abstract The efficiency of high-level waste (HLW) melters is limited by spinel settling and accumulation on the melter bottom if the waste loading is increased above a certain limit at which spinel crystallizes from the melt. Spinel accumulation interferes with melter operation and shortens melter lifetime. The mathematical modeling of spinel settling in a HLW melter was applied to define the critical level of spinel deposition during the lifetime of the melter and the corresponding increase in waste loading. In this study, spinel settled on the bottom, slant melter walls, and in the output pipe with a linear growth of spinel-sludge thickness after its concentration stabilized inside the melter. The calculations provided a higher concentration of spinel crystals in the melter regions where the temperature was lower then the liquidus temperature, i.e., T<TL. The effects of the following parameters on sludge-layer thickness were examined: 1) the impact of input concentration of spinel crystals of the same size, 2) the impact of different input size of spinel crystals of the same concentration entering from cold cap (melting batch on the melt surface), and 3) the influence of the average temperature (Tavg) inside of the melting space. The calculations showed that higher a concentration and bigger crystals caused thicker sludge layers in the melter, either because of a higher settling density of crystals or because of their higher settling rate. The nucleation of spinel crystals plays a more important role with decreasing of average temperature inside of the melter, and the thicker layer was formed at lower average temperatures.

Liquidus Temperature Model for Hanford High-Level Waste Glasses with High Concentrations of Zirconia

1996 ◽  
Vol 465 ◽  
Author(s):  
J. V. Crum ◽  
M. J. Schweiger ◽  
P. Hrma ◽  
J. D. Vienna
Keyword(s):  
Crystalline Phase ◽  
Liquidus Temperature ◽  
Heat Treating ◽  
Primary Phase ◽  
High Level Waste ◽  
Mass Fractions ◽  
High Concentrations ◽  
Phase Glass ◽  
High Level ◽  
Temperature Furnace

ABSTRACTA study was conducted on glasses based on a simulated transuranic waste with high concentrations of ZrO2and Bi2O3 to determine the compositional dependence of primary crystalline phases and liquidus temperature (TL). Starting from a baseline composition, glasses were formulated by changing mass fractions of Al2O3, B2O3, Bi2O3, CeO2, Li2O, Na2O, P2O5, SiO2, and ZrO2, one at a time, while keeping the remaining components in the same relative proportions as in the baseline glass. Liquidus temperature was measured by heat treating glass samples for 24 h in a uniform temperature furnace. The primary crystalline phase in the baseline glass and the majority of the glasses was zircon (ZrSiO4). A change in the concentration of certain components (Al2O3, ZrO2, Li2O, B2O3 and SiO2) changed the primary phase to baddeleyite (ZrO2), while cerium oxide (CeO2) precipitated from glasses with more than 3 wt% CeO2. Zircon TL was strongly increased by Al2O3, Zrb2 and CeO2, and slightly by P2O5 and SiO2; decreased strongly by Li2O and Na2O and moderately by B2O3. A first-order model was constructed for TL as a function of composition for zircon primary crystalline phase glass.

Static Leaching of Radioactive Glass Under Conditions Simulating a Granitic Repository for High-Level Waste: Phase 1.

1983 ◽  
Vol 26 ◽  
Author(s):  
Hans-Peter Hermansson ◽  
Hilbert Christensen ◽  
David E Clark ◽  
Inga-Kari Björner ◽  
Hayaichi Yokoyama ◽  
...  
Keyword(s):  
Phase 1 ◽  
High Level Waste ◽  
Borosilicate Glasses ◽  
Joint Research ◽  
Weight Losses ◽  
Infrared Reflection ◽  
Joint Research Project ◽  
Actinide Oxides ◽  
Leaching Experiments ◽  
High Level

ABSTRACTA joint research project with participation from Japan, Switzerland and Sweden is underway at Studsvik (The JSS-project). The project concerns investigations on the leaching of fully radioactive glass (containing 12 wt% fission product oxides and actinide oxides) manufactured by CEA/Marcoule.So far the glass has been leached in doubly distilled water and in silicate water at 90°C. Some leaching experiments involved the presence of crushed Stripa granite in the same containers as the glass.Due to strong radiation and the presence of plutonium the leaching was carried out in a specially designed lead cave using gilded stainless steel containers.Weight losses, pH and elemental mass losses were determined together with infrared reflection spectral changes. These data are compared to those obtained from a simulated nonradioactive glass of nearly the same composition and to similar alkali borosilicate glasses previously investigated at Studsvik.

The Long-Term Corrosion and Modelling of Two Simulated Belgian Reference High-Level Waste Glasses

1987 ◽  
Vol 112 ◽  
Author(s):  
P. Van Iseghem ◽  
B. Grambow
Keyword(s):  
Corrosion Behaviour ◽  
Stable Condition ◽  
High Level Waste ◽  
Forward Rate ◽  
Borosilicate Glasses ◽  
Al Content ◽  
Rate Of Dissolution ◽  
High Level ◽  
High Al Content

AbstractThe corrosion behaviour in distilled water of two simulated candidate high level waste borosilicate glasses (SAN602519L3C2 and SM58LW11) his been investigated at 90°C for different SA/V condition's 10, 100, 7800 m−1). The experimental data were modelled using the PHREEQE and GLASSOL computer codes. The model is quite successful for describing the corrosion behaviour, using experimentally derived values for the forward rate, silica saturation and the final rate. GWss SAN60 is more stable than glass SM58 at SA/V values of 10 and 100 m−1, but in the long term the relative performance is inverse. Indeed, the high Al content of SAN60 induces the creation of analcime crystals after SiO2 has reached its saturation concentration in solution, which cause an enhancement of the final rate of dissolution of the glass; for SM58 on the contrary the SiO2 solution is a stable condition.

Predicting Pu Concentrations in Solutions Contacting Geologic Materials

1981 ◽  
Vol 6 ◽  
Author(s):  
Richard G. Strickert ◽  
Dhanpat Rai
Keyword(s):  
Nuclear Waste ◽  
Safety Assessment ◽  
High Level Waste ◽  
Stable Phase ◽  
Borosilicate Glasses ◽  
Geologic Materials ◽  
Solid Phases ◽  
High Level ◽  
Waste Repositories

ABSTRACTKnowledge of Pu solid phases present in nuclear wastes is important for predicting the geochemical behavior of Pu. Thermodynamic data and experimental measurements using discrete Pu compounds, Pu-doped borosilicate glasses (simulating a high-level waste form), and Pu contaminated sediments suggest that PuO2(c) is very stable and is expected to be present in the repository. The solubility of the stable phase, such as PuO2(c), can be used to predict the maximum Pu concentration in solutions for long-term safety assessment of nuclear waste repositories.

scholarly journals The effect of high-level waste glass composition on spinel liquidus temperature

2014 ◽  
Vol 384 ◽  
pp. 32-40 ◽  
Author(s):  
Pavel Hrma ◽  
Brian J. Riley ◽  
Jarrod V. Crum ◽  
Josef Matyas
Keyword(s):  
Liquidus Temperature ◽  
Glass Composition ◽  
Waste Glass ◽  
High Level Waste ◽  
High Level
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