US4652404A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for conditioning contaminated waste through cementing
Assignee: Forschungszentrum Jülich
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Filing: 1984-11-30
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Granted: 1987-03-24
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Expires: 2004-11-30
Abstract
Abstract A process for the conditioning of contaminated waste through cementing. Dry waste is cemented, especially waste which is recovered as ashes subsequent to the combustion of burnable waste, or as a dry residue during the treatment of sludge. In the process there is added to the dry waste a cement component not less than about 50% by weight of the weight of the waste, wherein subsequent to the admixing of the waste with the cement, there is mixed in water to the cement in a slightly excess stoichiometric ratio of effecting the setting, and the mixture is compacted under pressure and then encased.
Inventors
- 👤 Heinz Mallek
- 👤 Egon Zange
- 👤 Wolfgang Schlenter
- 👤 Karl Trumper
- 👤 Siegfried Meininger
- 👤 Dietmar Bege
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:34
CPC Classifications
G; G21; G21F; G21F9/00; G21F9/28; G21F9/30; G21F9/301; G21F9/302; G21F9/304
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
142 words
In a process for the conditioning of contaminated waste through cementing, especially waste in the form of ashes obtained after the combustion of burnable waste or which is recovered as a dry residue during the treatment of sludge; the improvement comprising: adding a cement component to the dry waste which cement component is at least 50% by weight of the total weight of the waste, such that the quantity of dry waste relative to the quantity of cement is present in a ratio of about 2:1 by weight; adding water to the cement after the admixing of the waste with the cement for the setting of the cement, said water being in a slightly excess stoichiometric ratio to the cement to form a generally crumbly consistency; and compacting the mixture under pressure of at least about 7 MPa, and encasing the mixture.
Claim 2
Dependent Claim
142 words
In a process for the conditioning of contaminated waste through cementing, especially waste in the form of ashes obtained after the combustion of burnable waste or which is recovered as a dry residue during the treatment of sludge; the improvement comprising: adding a cement component to the dry waste which cement component is at least 50% by weight of the total weight of the waste, such that the quantity of dry waste relative to the quantity of cement is present in a ratio of about 2:1 by weight; adding water to the cement after the admixing of the waste with the cement for the setting of the cement, said water being in a slightly excess stoichiometric ratio to the cement to form a generally crumbly consistency; and compacting the mixture under pressure of at least about 7 MPa, and encasing the mixture.
Claim 3
Dependent Claim
27 words
A process as claimed in claim 1, wherein said water is added in the ratio of the mass of water:cement in the range of 0.29 to 0.35:1.
Claim 4
Dependent Claim
17 words
A process as claimed in claim 2, wherein the ratio of the mass of water:cement comprises 0.3:1.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-03-23 | 1990-09-22 | 1991-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-03-23 | 1994-09-22 | 1995-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-03-23 | 1998-09-22 | 1999-03-24 | $7700.00 | Window Closed / Lapsed |