Patent US4113184A successfully refreshed from Google Patents.
US4113184A
Expired / Lapsed
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Wet grinding method for crude phosphate rock
Assignee: CF Industries Inc
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Filing: 1977-09-19
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Granted: 1978-09-12
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Expires: 1997-09-19
Abstract
Abstract This application discloses a method of wet grinding crude phosphate rock containing clay minerals and the like impurities. The procedures of the invention produce a rock slurry of enhanced fluidity and a desired degree of economy; and the principles of the invention may be applied to rock slurries after size-reduction. The method of the invention contemplates introducing coarsely sized, crude phosphate rock with component clay minerals or the like into a grinding mill together with a suitable quantity of water and with an amount of a calcium-free alkaline amendment or additive material which is adequate to establish and maintain a pH of at least about 8.5 in the mixture.
Inventors
- 👤 Gregory D. Loughrie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:33
CPC Classifications
B; B02; B02C; B02C23/00; B02C23/06; C; C01; C01B; C01B25/00; C01B25/01
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
91 words
The method of wet grinding crude phosphate rock containing clay minerals or like siliceous impurities, which comprises the steps of: introducing coarsely sized, crude phosphate rock containing clay minerals or the like into a grinding mill with at least about 20% by weight of water; introducing a substantially calcium-free alkaline additive material into the mixture of crude rock and water to establish and maintain a pH of at least about 8.5 in the mixture; and wet grinding said mixture to a selected particle size whereby to produce a conveniently processable slurry.
Claim 2
Independent Claim
91 words
The method of wet grinding crude phosphate rock containing clay minerals or like siliceous impurities, which comprises the steps of: introducing coarsely sized, crude phosphate rock containing clay minerals or the like into a grinding mill with at least about 20% by weight of water; introducing a substantially calcium-free alkaline additive material into the mixture of crude rock and water to establish and maintain a pH of at least about 8.5 in the mixture; and wet grinding said mixture to a selected particle size whereby to produce a conveniently processable slurry.
Claim 3
Dependent Claim
15 words
The method according to claim 1 which further comprises the step of pumping said slurry.
Claim 4
Dependent Claim
20 words
The method according to claim 1 wherein the pH of said mixture is established between about 9.5 and about 10.0.
Claim 5
Dependent Claim
20 words
The method according to claim 1 wherein said slurry is maintained at a viscosity of less than about 1800 centipoises.
Claim 6
Dependent Claim
14 words
The method according to claim 1 wherein said alkaline additive material is caustic soda.
Claim 7
Dependent Claim
14 words
The method according to claim 1 wherein said alkaline additive material is caustic potash.
Claim 8
Dependent Claim
14 words
The method according to claim 1 wherein said alkaline additive material is ammonium hydroxide.
Claim 9
Dependent Claim
14 words
The method according to claim 1 wherein said alkaline additive material is sodium carbonate.
Claim 10
Independent Claim
47 words
The method of treating a mineral rock slurry to enhance the fluidity thereof which comprises the step of introducing a substantially calcium-free alkaline additive material into a slurry of mineral rock and water to establish and maintain a pH of at least about 8.5 in the mixture.
Claim 11
Independent Claim
47 words
The method of treating a mineral rock slurry to enhance the fluidity thereof which comprises the step of introducing a substantially calcium-free alkaline additive material into a slurry of mineral rock and water to establish and maintain a pH of at least about 8.5 in the mixture.
Claim 12
Dependent Claim
20 words
The method according to claim 9 wherein the pH of the mixture is established between about 9.5 and about 10.0.
References Cited (Backward Citations)
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US2843456A
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US3113838A
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US3204877A
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US4044107A
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US4042666A
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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) | 1981-09-11 | 1982-03-13 | 1982-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-11 | 1986-03-13 | 1986-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-11 | 1990-03-13 | 1990-09-12 | $7700.00 | Window Closed / Lapsed |