Leach Models for a Commercial Nuclear Waste Glass

1982 ◽  
Vol 15 ◽  
Author(s):  
William L. Kuhn ◽  
Richard D. Peters
Keyword(s):  
Nuclear Waste ◽  
Protective Layer ◽  
Volume Ratio ◽  
Surface Processes ◽  
Reaction Products ◽  
Leaching Behavior ◽  
Rate Laws ◽  
Nuclear Waste Glass ◽  
Soluble Species ◽  
Effect Of Surface

ABSTRACTA review of the leaching behavior of 76–68 glass shows that it cannot be explained in terms of diffusion in the glass, which has been the basis for several leach models. Instead, we present two models based on a dissolution rate impeded by surface processes: the accumulation of a protective layer of insoluble reaction products, and adsorption of reaction products on the surface. The resulting predicted time dependences are identical and predict a change from linear to parabolic rate laws for soluble species, which is found to agree with the data over a range of temperatures. Incongruent release is attributed primarily to solubility effects. The relative merits of the models are discussed on the basis of the effect of surface area-to-volume ratio in static leach tests. Their relevance to modeling repository behavior is discussed.

Effects of Flow Parameters on the Leaching of Nuclear Waste Glass

1984 ◽  
Vol 44 ◽  
Author(s):  
R. B. Adiga ◽  
E. P. Akomer ◽  
D. E. Clark
Keyword(s):  
Nuclear Waste ◽  
Flow Rate ◽  
Volume Ratio ◽  
Water Volume ◽  
Leaching Rate ◽  
Leaching Behavior ◽  
Waste Package ◽  
Flow Parameters ◽  
Nuclear Waste Glass ◽  
Independent Effects

Environmental conditions in a repository are expected to be significantly different from those encountered by a glass tested under MCC-1 specifications. In addition to variations in flow rate and glass surface area to water volume ratio (SA/V), the water chemistry and presence of waste package components in the repository will most certainly affect the leaching behavior of the glass. The independent effects of each of these variables have been studied by numerous investigators. For example, it is well known that the leaching rate increases as the flow rate increases (1). Also, the rate of approach to saturation is increased as SA/V is increased under MCC-1 type testing (2). The use of silicate water generally decreases the rate of leaching while waste package components such as iron enhances the leaching rate of glass under MCC-1 type testing (3–4).

Leaching behavior of nuclear waste glass heterogeneities

1986 ◽  
Vol 80 (1-3) ◽  
pp. 324-334 ◽  
Author(s):  
Zhu Bing-Fu ◽  
D.E. Clark ◽  
L.L. Hench ◽  
G.G. Wicks
Keyword(s):  
Nuclear Waste ◽  
Waste Glass ◽  
Leaching Behavior ◽  
Nuclear Waste Glass

237Np aND 239Pu Solution Behavior During Hydrothermal Testing of Simulated Nuclear Waste Glass with Basalt and Steel

1984 ◽  
Vol 44 ◽  
Author(s):  
Janet A. Schramke ◽  
Scott A. Simonson ◽  
David G. Coles
Keyword(s):  
Nuclear Waste ◽  
Cast Steel ◽  
Size Fraction ◽  
Weight Ratio ◽  
Reaction Products ◽  
Solid Materials ◽  
Solution Behavior ◽  
Waste Package ◽  
Hydrothermal Experiments ◽  
Nuclear Waste Glass

AbstractA series of hydrothermal experiments were carried out on 237Np- and 239Pu-doped PNL 76–68 glass, synthetic basalt groundwater, basalt, and cast steel. These hydrothermal experiments are part of the Basalt Waste Isolation Project investigation of the interactions of waste package components in a basalt repository. Experiments of three months duration were conducted in Dickson-type rocking autoclaves at 200°C and 30 MPa, with an initial fluid to solid weight ratio of 10:1. All solid materials were ground and sieved to a narrow size fraction. The experiments carried out were: glass and groundwater; glass, basalt, and groundwater; glass, steel, and groundwater; and glass, steel, basalt, and groundwater. Unfiltered, 4000 Â filtered, and 18 Å filtered solutions were analyzed to determine the concentrations of radionuclides in solution and those associated with colloids.The quantities of 237Np and 239Pu in solution were very small. Worstcase calculations indicate that 0.01% or less of the total radionuclide inventories were present in solution. The highest solution concentrations of the actinide dopants were observed in the experiments with basalt, even though smaller amounts of glass were dissolved than in the experiments without basalt. The observed differences in the solution concentrations of 237Np and 239Pu were probably controlled by differences in the reaction products, which were clinoptilolite in the experiments with basalt, and an Fe-Zn smectite clay in the experiments without basalt.

Role of Surface Layers in the Leaching Behavior of Glass

1988 ◽  
Vol 125 ◽  
Author(s):  
B.K. Zoitos ◽  
D.E. Clark
Keyword(s):  
Surface Layer ◽  
Nuclear Waste ◽  
Surface Composition ◽  
Analytical Techniques ◽  
Surface Layers ◽  
Leaching Behavior ◽  
Leach Rate ◽  
Layer Analysis ◽  
Nuclear Waste Glass

ABSTRACTResults are presented from a two-year dynamic leach test of nuclear waste glass under conditions designed to simulate those of the Stripa granite repository. Solution and surface analytical techniques were used to assess the glass leach rate as well as surface composition and morphology. Glass leach rates were observed to decrease by a factor of two during the first six months. This effect is attributed to the formation of a protective surface layer. Analysis of this layer shows it to be rich in silicon and iron and depleted in lithium, sodium and boron. It was also found that the layer is subject to dissolution.

Effect of Fe2O3/ZnO on Two Glass Compositions for Solidification of Swedish Nuclear Wastes

1981 ◽  
Vol 11 ◽  
Author(s):  
J. L. Nogues ◽  
L. L. Hench
Keyword(s):  
Nuclear Waste ◽  
Glass Surface ◽  
Fission Products ◽  
Waste Glass ◽  
Nuclear Wastes ◽  
Leaching Behavior ◽  
Waste Products ◽  
Simulated Waste ◽  
Nuclear Waste Glass ◽  
Glass Compositions

A recent study concluded that addition of Fe203 to a soda borosilicate nuclear waste glass may significantly reduce damage by water attack due to formation of a Fe-rich film on the glass surface. However, differences in SiO2, B203, CaO, and concentration of fission products in previous glass compositions make it impossible to ascribe the improved leach resistance solely to Fe203 content. In the present work, leaching behavior of two glasses are compared which differ only by the substitution of Fe203 for some of the ZnO in the glass. Both glass compositions, Table 1, are compatible with the French AVM process and contain 9% (by weight) of simulated waste products characteristic of the Swedish nulcear waste program.

Infrared Spectroscopy Structural Analysis of Corroded Nuclear Waste Glass K-26

2008 ◽  
Author(s):  
Sergey Stefanovsky ◽  
Alexander Barinov ◽  
Galina Varlakova ◽  
Irene Startseva ◽  
Michael I. Ojovan
Keyword(s):  
Infrared Spectroscopy ◽  
Structural Analysis ◽  
Nuclear Waste ◽  
Waste Glass ◽  
Nuclear Waste Glass

scholarly journals History of Nuclear Waste Glass in France

2014 ◽  
Vol 7 ◽  
pp. 3-9 ◽  
Author(s):  
Étienne Vernaz ◽  
Jérôme Bruezière
Keyword(s):  
Nuclear Waste ◽  
Waste Glass ◽  
Nuclear Waste Glass ◽  
History Of

Hydrotalcite Formed by Alteration of R7T7 Nuclear Waste Glass and Basaltic Glass in Salt Brine at 190°C

1993 ◽  
Vol 333 ◽  
Author(s):  
A. Abdelouas ◽  
J. L. Crovisier ◽  
W. Lutze ◽  
R. Müller ◽  
W. Bernotat
Keyword(s):  
Nuclear Waste ◽  
Waste Glass ◽  
Aluminium Content ◽  
Basaltic Glass ◽  
Alteration Product ◽  
Nuclear Waste Glass ◽  
Salt Brine ◽  
High Aluminium ◽  
Early Alteration

ABSTRACTThe R7T7 and synthetic basaltic glasses were submitted to corrosion in a saline MgCl2dominated solution at 190°C. For both glasses, the early alteration product is a hydrotalcite-like compound in which HPO42-, SO4-2and Cl-substitutes to CO32. The measured d003spacing is 7.68 Å for the hydrotalcite formed from R7T7 glass and 7.62 Å for the hydrotalcite formed from basaltic glass which reflect the high aluminium content. Chemical microanalyses show that the hydrotalcite is subsequently covered by a silica-rich gel which evolves into saponite after few months.

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