US4726916A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for embedding and storing dangerous materials, such as radioactive materials in a monolithic container
Assignee: Societe Generale pour les Techniques Nouvelles SA SGN
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Filing: 1985-04-30
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Granted: 1988-02-23
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Expires: 2005-04-30
Abstract
Abstract The present invention relates to a method for immobilizing and packing radioactive "ashes" in a mineral matrix, said method consisting in adjusting the coefficient of expansion of said ashes, molding around said ashes a porcelain in the raw state and taking the whole in one operation to form a hermetically sealed block.
Inventors
- 👤 Bruno Aubert
- 👤 Serge Carpentier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:37
CPC Classifications
B; B30; B30B; B30B11/00; B30B11/34; G; G21; G21F; G21F9/00; G21F9/28; G21F9/34
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
136 words
A method of containing and immobilizing radioactive waste material comprising the steps of: (a) forming by molding under pressure a containment vessel having a bottom and side walls, said containment vessel being formed from a porcelain slip; (b) mixing the radioactive waste with a ceramic-forming composition in proportions such that the coefficient of expansion of said mixture is substantially equal to the coefficient of expansion of said porcelain containment vessel; (c) depositing the radioactive waste/ceramic-forming composition mixture into said containment vessel; (d) compacting said mixture under pressure; (e) placing a cover over said containment vessel, said cover comprising a layer of the porcelain slip; and (f) heating the covered vessel at atmospheric pressure so as to allow any gases formed during heating to escape from the vessel and to solidify said vessel and the mixture therein.
Claim 2
Independent Claim
136 words
A method of containing and immobilizing radioactive waste material comprising the steps of: (a) forming by molding under pressure a containment vessel having a bottom and side walls, said containment vessel being formed from a porcelain slip; (b) mixing the radioactive waste with a ceramic-forming composition in proportions such that the coefficient of expansion of said mixture is substantially equal to the coefficient of expansion of said porcelain containment vessel; (c) depositing the radioactive waste/ceramic-forming composition mixture into said containment vessel; (d) compacting said mixture under pressure; (e) placing a cover over said containment vessel, said cover comprising a layer of the porcelain slip; and (f) heating the covered vessel at atmospheric pressure so as to allow any gases formed during heating to escape from the vessel and to solidify said vessel and the mixture therein.
Claim 3
Dependent Claim
22 words
A method as claimed in claim 1, wherein the used porcelain slip is a pulverized slip containing preferably 4 to 7% water.
Claim 4
Dependent Claim
24 words
Method as claimd in claim 1, wherein the ceramic-forming composition is composed of silicates or alumino silicates of alkaline, alkaline-earth metals, or of magnesium.
Claim 5
Dependent Claim
13 words
Method as claimed in claim 1, wherein said ceramic-forming composition is a porcelain.
Claim 6
Dependent Claim
20 words
Method as claimed in claim 4, wherein the porcelain is composed of a mixture of feldspar, clay, sand and kaolin.
Claim 7
Dependent Claim
27 words
Method as claimed in claim 1, wherein the radioactive waste is ashes from incineration or from a calcinate of solution of fission products or of lead iodide.
Claim 8
Dependent Claim
13 words
A method according to claim 5, wherein the porcelain is enriched with alumina.
References Cited (Backward Citations)
US3170578A
Cited
US3249551A
Cited
US3358590A
Cited
US4172807A
Cited
US4297304A
Cited
US4224177A
Cited
US4362659A
Cited
US4354954A
Cited
US4312774A
Cited
US4303412A
Cited
US4333847A
Cited
US4534893A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-02-22 | 1991-08-24 | 1992-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-22 | 1995-08-24 | 1996-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-22 | 1999-08-24 | 2000-02-23 | $7700.00 | Window Closed / Lapsed |