US4091070A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of copper
Assignee: Inspiration Consolidated Copper Co
•
Filing: 1976-08-25
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Granted: 1978-05-23
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Expires: 1996-08-25
Abstract
Abstract Copper is recovered from ores containing sulfidic copper minerals by forming the ore into a dump leach heap, and substantially saturating (i.e. thoroughly wetting) the ore in the heap with an aqueous strong acid solution containing 100 to 400 g/l H 2 SO 4 and 5 to 50 g/l ferric ion. The ore thus saturated is cured in contact with the strong acid solution for a curing period of at least 2 days, and generally from 5 days to 6 months or even longer, depending on the character of the ore and its permeability by the acid solution. The ore in the heap may be run of mine size, or may be coarsely crushed, again depending on permeability to the strong acid solution. After the curing period, the ore in the heap is washed by percolating through it a weak acid solution containing up to 50 g/l H 2 SO 4 and 5 to 50 g/l ferric ion. The wash solutions are collected and treated for copper recovery. Washing is continued until the copper content of the heap has been largely extracted.
Inventors
- 👤 William F. Riggs
- 👤 Jaime Veloz
- 👤 Harry R. Dahlberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 23:55
CPC Classifications
C; C22; C22B; C22B15/00; C22B15/0063; C22B15/0065; C22B15/0067; C22B15/0071; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
129 words
A method of treating a copper ore containing sulfidic copper minerals which comprises forming the ore into a dump leach heap of a depth of at least about ten feet, substantially saturating the ore in such heap with an aqueous strong acid solution containing 100 to 400 g/l H 2 SO 4 and 5 to 50 g/l ferric ion, maintaining the ore in the heap thus saturated in contact with such strong acid solution for a curing period of at least 2 days, thereafter washing the cured heap by percolating therethrough a weak acid wash solution containing up to 50 g/l H 2 SO 4 and 5 to 50 g/l ferric ion, and collecting such wash solution pregnant with dissolved copper after it has passed through the cured heap.
Claim 2
Independent Claim
129 words
A method of treating a copper ore containing sulfidic copper minerals which comprises forming the ore into a dump leach heap of a depth of at least about ten feet, substantially saturating the ore in such heap with an aqueous strong acid solution containing 100 to 400 g/l H 2 SO 4 and 5 to 50 g/l ferric ion, maintaining the ore in the heap thus saturated in contact with such strong acid solution for a curing period of at least 2 days, thereafter washing the cured heap by percolating therethrough a weak acid wash solution containing up to 50 g/l H 2 SO 4 and 5 to 50 g/l ferric ion, and collecting such wash solution pregnant with dissolved copper after it has passed through the cured heap.
Claim 3
Dependent Claim
17 words
The method according to claim 1 wherein the ore contains oxidized as well as sulfidic copper minerals.
Claim 4
Dependent Claim
17 words
The method according to claim 1 wherein the ore is crushed to minus four inch particle size.
Claim 5
Dependent Claim
21 words
The method according to claim 1 wherein the strong acid solution contains 150 to 300 g/l H 2 SO 4 .
Claim 6
Dependent Claim
18 words
The method according to claim 1 wherein the strong acid solution contains 10 to 25 g/l ferric ion.
Claim 7
Dependent Claim
30 words
The method according to claim 1 wherein the amount of strong acid used to saturate the ore in the heap is from 5% to 15% by weight of the ore.
Claim 8
Dependent Claim
28 words
The method according to claim 1 wherein the ore is held in contact with the strong acid solution for a curing period of 5 days to 6 months.
Claim 9
Dependent Claim
37 words
The method according to claim 1 wherein the sulfidic minerals comprise a substantial proportion of chalcocite and the ore is held in contact with the strong acid solution for a curing period of 5 to 50 days.
Claim 10
Dependent Claim
27 words
The method according to claim 8 wherein the ore is held in contact with the strong acid solution for a curing period of 10 to 25 days.
Claim 11
Dependent Claim
37 words
The method according to claim 1 wherein the sulfide minerals comprise a substantial proportion of chalcopyrite and the ore is held in contact with the strong acid solution for a curing period of 1 to 6 months.
Claim 12
Dependent Claim
22 words
The method according to claim 1 wherein the weak acid wash solution contains 2 to 25 g/l H 2 SO 4 .
Claim 13
Dependent Claim
19 words
The method according to claim 1 wherein the weak acid wash solution contains 10 to 25 g/l ferric ion.
Claim 14
Dependent Claim
23 words
The method according to claim 1 wherein the ferric ion is supplied in the form of Fe 2 (SO 4 ) 3 .
Claim 15
Independent Claim
172 words
A method of treating a mixed copper ore containing both oxidic and sulfidic copper minerals including a substantial proportion of chalcocite which comprises coarsely crushing such ore, forming the crushed ore into a dump leach heap of a depth of at least about ten feet, substantially saturating the ore in such heap with an aqueous strong acid solution containing 150 to 300 g/l H 2 SO 4 and sufficient ferric sulfate to supply 10 to 25 g/l ferric ion, maintining the ore in the heap thus saturated for a curing period of 10 to 25 days, thereafter washing the cured heap by percolating therethrough a weak acid wash solution containing 2 to 25 g/l H 2 SO 4 and sufficient ferric sulfate to supply 10 to 25 g/l ferric ion, collecting the wash solution pregnant with dissolved copper after it has passed through the cured heap and recovering such dissolved copper from the wash solution, and continuing such washing of the cured heap until the copper content thereof has been largely extracted.
Claim 16
Independent Claim
172 words
A method of treating a mixed copper ore containing both oxidic and sulfidic copper minerals including a substantial proportion of chalcocite which comprises coarsely crushing such ore, forming the crushed ore into a dump leach heap of a depth of at least about ten feet, substantially saturating the ore in such heap with an aqueous strong acid solution containing 150 to 300 g/l H 2 SO 4 and sufficient ferric sulfate to supply 10 to 25 g/l ferric ion, maintining the ore in the heap thus saturated for a curing period of 10 to 25 days, thereafter washing the cured heap by percolating therethrough a weak acid wash solution containing 2 to 25 g/l H 2 SO 4 and sufficient ferric sulfate to supply 10 to 25 g/l ferric ion, collecting the wash solution pregnant with dissolved copper after it has passed through the cured heap and recovering such dissolved copper from the wash solution, and continuing such washing of the cured heap until the copper content thereof has been largely extracted.
Claim 17
Dependent Claim
25 words
The method according to claim 14 wherein the strong acid solution contains substantially 200 g/l H 2 SO 4 and substantially 15 g/l ferric ion.
Claim 18
Dependent Claim
32 words
The method according to claim 14 wherein the amount of strong acid solution employed to saturate the ore in the heap is substantially 7% by weight of the ore in the heap.
Claim 19
Dependent Claim
28 words
The method according to claim 14 wherein the ore in the heap is cured by maintaining it in contact with the strong acid solution for substantially 15 days.
Claim 20
Dependent Claim
25 words
The method according to claim 14 wherein the weak acid wash solution contains substantially 15 g/l each of H 2 SO 4 and ferric ion.
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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) | 1981-05-22 | 1981-11-21 | 1982-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-22 | 1985-11-21 | 1986-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-22 | 1989-11-21 | 1990-05-23 | $7700.00 | Window Closed / Lapsed |