Hostname: page-component-84b7d79bbc-5lx2p Total loading time: 0 Render date: 2024-07-28T20:16:56.329Z Has data issue: false hasContentIssue false
  • English
  • Français

Powder Technological Vitrification of High Level Nuclear Waste by In-Can Hot Pressing Including a Sol-Gel Route

Published online by Cambridge University Press:  26 February 2011

A. Caneiro ,
G. Ondracek  and
Toscano E.H.
A. Caneiro
Affiliation:
On leave from Comisión Nacional de Energia Atómica, Argentina for scientific-technical cooperation KfK/CNEA.
G. Ondracek
Affiliation:
Kernforschungszentrum Karlsruhe, Institut für Material- und Festkörperforschung, Postfach 3640, D-7500 Karlsruhe, Federal Republic of Germany
Toscano E.H.
Affiliation:
Kernforschungszentrum Karlsruhe, Institut für Material- und Festkörperforschung, Postfach 3640, D-7500 Karlsruhe, Federal Republic of Germany
Get access

Abstract

Powder technology is used to immobilize high level nuclear waste (HLW) in sintered borosilicate glass. By uniaxial in-can hot pressing(temperature 950 K; pressure 1 MPa; heating rate ∼100 K/h; cooling rate 5 K/h), glass products containing simulated HLW(15 wt.%) have been produced in stackable steel cans (≤ 200 mm diameter). High densities, bulk integrities and homogeneities for the waste element distribution are realized. The advantages of powder technology are for example: (i) no segregation due to solid state vitrification, (ii) low evaporation losses and no compatibility problems due to low densification temperatures (sinter temperature ∼0.6 softening temperature of glass), (iii) production in easily arrangeable and interchangeable stacking units at modest pressures adequate especially for the use in hot cells under remote handling conditions, (iv) choosing units with alternatively HLWo r MLWin prescribed sequences to control the heat production of the package. As demonstrated now, the process is appropriate for high level waste (HLW), medium level waste (MLW) and mixed (HLW/ MLW vitrification, and is insensitive to waste modifications.

As the next step the effect of glass modifications was studied. In order to improve the glass leaching resistance and maintain low viscosity, silicon dioxide was doped with titanium dioxide. The mixture (referring to eutectic composition) was produced by a sol gel route and combined finally with 15 w/o HLW-oxides. Hot pressing of the obtained gels at 1273 K and 20 MPa provided highly homogeneous products with high densities.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 44: Symposium N – Scientific Basis for Nuclear Waste Management VIII , 1984 , 817
Copyright
Copyright © Materials Research Society 1985

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

[1] Ondracek, G., Toscano, E.H.; J. Nucl. Mat. 24 (1984) 75 Google Scholar
[2] Bauer, C., Ondracek, G.; Atomkernenergie - Kerntechnik 43–1 (1983) 55; KfK 3649 (1983)Google Scholar
[3] Ondracek, G.; European Patent EP 0028 670B1 (1983)Google Scholar
[4] Ondracek, G.; KfK 2940 (1980) 278 Google Scholar
[5] Roy, R.; J. Amer. Ceram. Soc. 52 (1956) 344 Google Scholar
[6] Decottignies, M., Phalippou, J., J. Zarzycki; J. Mater. Sci. 13 (1978) 2605 Google Scholar
[7] Zarzycki, J.; J. Non-Cryst. Sol. 48 (1982) 105 Google Scholar
[8] Bauer, C.; Ph D Thesis, University of Karlsruhe, Fakultät Maschinenbau (1982)Google Scholar
[9] Bauer, C., Ondracek, G.; Mat. Res. Soc. Symp. Proc. 15 (1982) 72 Google Scholar
[10] Ondracek, G., Toscano, E.H.; Mat. Res. Soc. Symp. Proc., 26 (1982) 591 CrossRefGoogle Scholar
[11] Schultz, P.; J. Amer. Ceram. Soc. 59 (1976) 214 Google Scholar
[12] Yoldas, B.E.; J. Mater. Sci. 12 (1977) 1203 Google Scholar
[13] Simmons, J.H., Macedo, P.B., Barkatt, A., Litovitz, T.A.; Nature 278 (1978) 729 Google Scholar