Patent US4256705A successfully refreshed from Google Patents.
US4256705A
Expired / Lapsed
US
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Leaching agglomerated gold - silver ores
Assignee: United States Department of the Interior
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Filing: 1980-04-17
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Granted: 1981-03-17
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Expires: 2000-04-17
Abstract
Abstract Percolation leaching of gold or silver ores, tailings or wastes is accomplished by a process comprising initial agglomeration of fines in the feed by means of a binding agent and water, followed by aging and, subsequently, leaching to recover gold or silver values.
Inventors
- 👤 Harold J. Heinen
- 👤 Gene E. McClelland
- 👤 Roald E. Lindstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:59
CPC Classifications
C; C22; C22B; C22B11/00; C22B11/08; C22B11/04; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
109 words
A process for percolation leaching of gold or silver values from a feed material consisting of ores, tailings or wastes comprising: (1) admixing the feed with about 0.25 to 0.75 weight percent of a binding agent consisting of lime, portland cement, or mixtures thereof, and about 8 to 16 weight percent of water, (2) mechanically manipulating the admixture to effect agglomeration of fines in the feed, (3) aging the admixture at ambient conditions for a time sufficient to provide the resulting agglomerates with green strength sufficient to withstand further wetting without disintegration, and (4) subjecting the aged admixture to percolation leaching with a leach solution for gold or silver.
Claim 2
Dependent Claim
109 words
A process for percolation leaching of gold or silver values from a feed material consisting of ores, tailings or wastes comprising: (1) admixing the feed with about 0.25 to 0.75 weight percent of a binding agent consisting of lime, portland cement, or mixtures thereof, and about 8 to 16 weight percent of water, (2) mechanically manipulating the admixture to effect agglomeration of fines in the feed, (3) aging the admixture at ambient conditions for a time sufficient to provide the resulting agglomerates with green strength sufficient to withstand further wetting without disintegration, and (4) subjecting the aged admixture to percolation leaching with a leach solution for gold or silver.
Claim 3
Dependent Claim
21 words
The process of claim 1 in which the feed material is a low-grade clayey gold or silver ore, tailing or waste.
Claim 4
Dependent Claim
13 words
The process of claim 2 in which the binding agent is portland cement.
Claim 5
Dependent Claim
16 words
The process of claim 1 in which the aging time is about 5 to 72 hours.
Claim 6
Dependent Claim
14 words
The process of claim 1 in which the leach solution is a cyanide solution.
Claim 7
Dependent Claim
14 words
The process of claim 1 in which the percolation leaching consists of heap leaching.
Claim 8
Dependent Claim
16 words
The process of claim 1 in which the percolation leaching consists of vat of flood leaching.
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) | 1984-03-16 | 1984-09-15 | 1985-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-16 | 1988-09-15 | 1989-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-16 | 1992-09-15 | 1993-03-17 | $7700.00 | Window Closed / Lapsed |