Patent US4741834A successfully refreshed from Google Patents.
US4741834A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for underground support and removal of hazardous ions in ground waters
Assignee: Dow Chemical Co
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Filing: 1986-05-08
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Granted: 1988-05-03
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Expires: 2006-05-08
Abstract
Abstract Rectifying the compressive strength and toxic waste levels of ground water passages is achieved through the formation of a type C fly ash screen reinforcement of the passage.
Inventors
- 👤 Lloyd B. Spangle
- 👤 S. Ebow Coleman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:35
CPC Classifications
A; A62; A62D; A62D3/00; A62D3/30; A62D3/33; C; C02; C02F; C02F1/00; C02F1/28; C02F1/281; C04; C04B; C04B28/00; C04B28/02; C04B28/021; C04B28/18; A62D2101/00; A62D2101/20; A62D2101/24; A62D2101/40; A62D2101/43; A62D2101/45; A62D2101/47; A62D2101/49; C04B2111/00; C04B2111/00034; C04B2111/00146; C04B2111/00241; C04B2111/00284; C04B2111/00474; C04B2111/00767; C04B2111/00775; C04B2111/00793; Y; Y10; Y10S; Y10S106/00; Y10S106/01; Y10S210/00; Y10S210/901
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
108 words
A method for rectifying ground water passages comprising, (a) forming a pumpable slurry of Type C fly ash containing at least about 8% by weight CaO and at least about 5% by weight tricalcium aluminate and water comprising from about 40 to about 300% water by weight of the ash; (b) grouting the pumpable slurry into the passage; (c) permitting the pumpable slurry to cure until it sets into a water permeable screen; and (d) contacting said screen with ground water contaminated with hazardous waste; whereby hazardous wastes are removed from the ground water and retentatively fixed, while simultaneously reinforcing the compressive strength of the ground water passage.
Claim 2
Independent Claim
108 words
A method for rectifying ground water passages comprising, (a) forming a pumpable slurry of Type C fly ash containing at least about 8% by weight CaO and at least about 5% by weight tricalcium aluminate and water comprising from about 40 to about 300% water by weight of the ash; (b) grouting the pumpable slurry into the passage; (c) permitting the pumpable slurry to cure until it sets into a water permeable screen; and (d) contacting said screen with ground water contaminated with hazardous waste; whereby hazardous wastes are removed from the ground water and retentatively fixed, while simultaneously reinforcing the compressive strength of the ground water passage.
Claim 3
Dependent Claim
20 words
The method of claim 1 wherein the amount of tricalcium aluminate is between about 7% and about 9% by weight.
Claim 4
Dependent Claim
27 words
The method of claim 1 wherein the pumpable slurry is cured to at least 20 psi within 24 hours under from about 40° to about 150° F.
Claim 5
Dependent Claim
15 words
The method of claim 3 wherein the temperature is no more than 120 degrees F.
Claim 6
Dependent Claim
15 words
The method of claim 1 wherein the Type C fly ash is slurried with cement.
Claim 7
Dependent Claim
18 words
The method of claim 5 wherein the weight ratio of Type C fly ash to cement is 1:1.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-05-03 | 1991-11-02 | 1992-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-03 | 1995-11-02 | 1996-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-03 | 1999-11-02 | 2000-05-03 | $7700.00 | Window Closed / Lapsed |