Calculation of the Viscosity of Nuclear Waste Glass Systems

1989 ◽  
Vol 176 ◽  
Author(s):  
R. Shah ◽  
E.C. Behrman ◽  
D. Oksoy
Keyword(s):  
Nuclear Waste ◽  
Processing Parameters ◽  
Mechanical Perturbation ◽  
First Order ◽  
Nuclear Waste Glass ◽  
Important Processing ◽  
Key Variables ◽  
Statistical Mechanical ◽  
Semi Empirical ◽  
Theory Calculation

ABSTRACTViscosity is one of the most important processing parameters and one of the most difficult to calculate theoretically, particularly for multicomponent systems like nuclear waste glasses. Here, we propose a semi-empirical approach based on the Fulcher equation, involving identification of key variables, for which coefficients are then determined by regression analysis. Results are presented for two glass systems, and compared to results of previous workers and to experiment. We also sketch a first-order statistical mechanical perturbation theory calculation for the effects on viscosity of a change in composition of the melt.

Borosilicate Nuclear Waste Glass Alteration Kinetics: Chemical Inhibition and Affinity Control

1997 ◽  
Vol 506 ◽  
Author(s):  
T. Advocat ◽  
J. L. Chouchan ◽  
J. L. Crovisier ◽  
C. Guy ◽  
V. Daux ◽  
...  
Keyword(s):  
Nuclear Waste ◽  
Mathematical Formulation ◽  
Order Kinetic ◽  
Exact Role ◽  
Dissolved Silica ◽  
First Order ◽  
Nuclear Waste Glass ◽  
Chemical Inhibition ◽  
Kinetics Of

ABSTRACTThe objective of this work was to develop a more representative mathematical formulation of the alteration kinetics of the borosilicate SON68 glass by combining three approaches: (1) Compare extensive prior experimental static leaching results for SON68 glass with the first-order kinetic law in which silica is the predominant element, (2) Assess the exact role of dissolved silica on the alteration rate under conditions near and far from saturation, by means of dynamic leach tests and, (3) Compare the new data with the general kinetic law for silicates in which the reaction affinity, catalysis and inhibition are the three influencing factors.

Effects of α-Decay on Mechanical Properties of Simulated Nuclear Waste Glass

1992 ◽  
Vol 294 ◽  
Author(s):  
Y. Inagaki ◽  
H. Furuya ◽  
Y. Ono ◽  
K. Idemitsu ◽  
T. Banba ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Young’S Modulus ◽  
Nuclear Waste ◽  
Annealing Temperature ◽  
Volume Fraction ◽  
Young's Modulus ◽  
Waste Glass ◽  
Α Decay ◽  
First Order ◽  
Nuclear Waste Glass

ABSTRACTA simulated nuclear waste glass was self-irradiated by doping with short-lived actinides of 238Pu and 244Cm. Changes in the hardness, the Young's modulus and the fracture toughness, as a function of irradiation dose, were measured by use of indentation techniques. The irradiated glass was annealed at temperatures from 573K to 723K for periods of up to 48hours, and the recovery of these changes were measured as a function of annealing temperature and time.It was observed that the hardness and the Young's modulus decreased, while the fracture toughness increased exponentially with the cumulative dose. The maximum values of the relative changes in the hardness, the Young's modulus and the fracture toughness were about −25%, −30% and +45%, respectively. The results of the annealing show that the hardness and the Young's modulus were almost recovered to the original values at temperatures above 673K within 10 hours, while the recovery of the fracture toughness was minimal in this region of temperature and time. The changes in the hardness and the Young's modulus can be well explained by the model, in which the changes is proportional to the volume fraction of damaged zones, F, and the recovery of F is first order. On the other hand, the changes in the fracture toughness cannot be explained by the model, which suggests that the mechanism of the change in the fracture toughness is different from that in the hardness and the Young's modulus.

Dissolution of R7T7 Glass in Static and Flowing Conditions: Influence of Si Diffusion Mechanism in the Leached Layer

1992 ◽  
Vol 294 ◽  
Author(s):  
F. Delage ◽  
F. Larche ◽  
E. Vernaz
Keyword(s):  
Nuclear Waste ◽  
Mechanistic Model ◽  
Diffusion Mechanism ◽  
Interstitial Solution ◽  
First Order ◽  
Glass Dissolution ◽  
Nuclear Waste Glass ◽  
Empirical Law ◽  
Mass Transport Equation ◽  
Silicon Diffusion

ABSTRACTLeach tests with R7T7 nuclear waste glass in distilled water were conducted at 50 and 90°C under static and slow flowing conditions, with an SA/V ratio of 50 m−1. A computer model for glass dissolution (LIXIVER) Was used to interpret the experimental data. This mechanistic model is based on a combination of the first-order law governing surface reactions, the silicon mass transport equation for the interstitial solution in the alteration film, and an empirical law for partial silicon retention in the alteration layer. The LIXIVER model satisfactorily accounts for most of the experimental results. The importance of the silicon diffusion mechanism in the diffusion layer is stressed. Values are indicated for the apparent silicon diffusion coefficient, Dsi, which ranged from 10−16 to 10−14 m2·s−1 at 50°C, and from 10−15 to 10−13 m2·s−1 at 90°C.

Development of Ceramic Waste Forms for High-Level Nuclear Waste over the Last 30 years

2006 ◽  
Vol 985 ◽  
Author(s):  
Eric Vance
Keyword(s):  
Nuclear Waste ◽  
Nuclear Power ◽  
Waste Treatment ◽  
Processing Parameters ◽  
Point Of View ◽  
High Level Waste ◽  
Chemical Design ◽  
Important Processing ◽  
High Level Nuclear Waste ◽  
High Level

AbstractMany types of ceramics have been put forward for immobilisation of high-level waste (HLW) from reprocessing of nuclear power plant fuel or weapons production. After describing some historical aspects of waste form research, the essential features of the chemical design and processing of these different ceramic types will be discussed briefly. Given acceptable laboratory and long-term predicted performance based on appropriately rigorous chemical design, the important processing parameters are mostly waste loading, waste throughput, footprint, offgas control/minimisation, and the need for secondary waste treatment. It is concluded that the “problem of high-level nuclear waste” is largely solved from a technical point of view, within the current regulatory framework, and that the main remaining question is which technical disposition method is optimum for a given waste.

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.

scholarly journals Does Fully Radioactive Glass Behave Differently than Simulated Waste Glass?

1992 ◽  
Vol 294 ◽  
Author(s):  
X. Feng ◽  
J. K. Bates ◽  
C. R. Bradley ◽  
E. C. Buck
Keyword(s):  
Radiation Field ◽  
Nuclear Waste ◽  
Potassium Feldspar ◽  
Waste Glass ◽  
Solution Ph ◽  
Static Tests ◽  
Leach Rate ◽  
Nuclear Waste Glass ◽  
Surface Alteration ◽  
Leach Behavior

ABSTRACTStatic tests at SA/V (ratio of surface area of glass to solution volume) 20,000 m−1 on SRL 200 glass compositions show that, at long test periods, the simulated nuclear waste glass (nonradioactive) leaches faster than the corresponding radioactive glass by a factor of about 40, although comparative tests, done through 560 days, at lower SA/V, 2000 m−1, indicate little difference in the leach behavior of the two types of glasses. The similarity in leach behavior between radioactive and simulated glasses at SAN of 2000 m−1 or lower is also observed for SRL 165/42 and 131/11 compositions. The accelerated glass reaction with the simulated glass 200S is associated with the formation of crystalline phases such as clinoptilolite (or potassium feldspar), and a pH excursion. The radiation field generated by the fully radioactive glass reduces the solution pH. This lower pH, in turn, may retard the onset of increased reaction rate. The radiation field generated by the radioactive glasses does not directly affect the stability of the glass surface alteration layer under those conditions where the radioactive and simulated glasses react at the same rate. These results suggest that the fully radioactive nuclear waste glass 200R may maintain a much lower leach rate than the simulated 200S, if the lower pH in the 200R leachate can be sustained. Meaningful comparison tests between radioactive and simulated nuclear waste glasses should include long-term and high SA/V tests.

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