US3782539A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Beneficiation of phosphate ores
Assignee: Pm Holding Co
•
Filing: 1971-11-01
•
Granted: 1974-01-01
•
Expires: 1991-11-01
Abstract
Abstract A process for beneficiating phosphate ores in which the ore is scrubbed and deslimed prior to separation into a coarse fraction and a fine fraction, each of which is subjected to a plurality of anionic flotation steps and screening steps to obtain high recovery and high grade phosphate product whereby the acid cleaning and cationic flotation steps previously used are eliminated.
Inventors
- 👤 W Painter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:43
CPC Classifications
B; B03; B03D; B03D1/00; B03D1/02; B03D1/021; B03B; B03B7/00
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
67 words
A process as claimed in claim 1 and further comprising screening at about 20 mesh the scrubbed ore, grinding the oversized material from said screening step and recyling said ground oversized material to said screening step and further comprising a second scrubbing step of the deslimed ore material and a second desliming step, the slime from said second desliming step being recycled to the first desliming step.
Claim 2
Dependent Claim
65 words
A process as claimed in claim 1 and further comprising passing the tailings from the at least one rougher flotation machine for the coarse slurry to a screening step having an effective mesh of separation from about 28 to about 65 mesh, passing the undersized material to final tailings, grinding the oversized material and passing the ground material to the thickener for the fine fraction.
Claim 3
Dependent Claim
58 words
A process as claimed in claim 3 and further comprising passing the tailings from the at least one cleaner flotation machine for the coarse fraction to a screen having an effective mesh of separation from about 28 to about 65 mesh and recycling the undersized material to the at least one rougher flotation machine for the coarse fraction.
Claim 4
Dependent Claim
53 words
A process as claimed in claim 4 and further comprising passing the tailings from the at least one cleaner flotation machine for the coarse fraction to a screen having an effective mesh of separation from about 28 to about 65 mesh and passing the undersized material to the thickener for the fine fraction.
Claim 5
Dependent Claim
124 words
A process as claimed in claim 1 and further comprising passing the tailings from the at least one cleaner flotation machine for the coarse fraction to a screening step on a fixed flat inclined or curved screen of the Dutch State mines type and to which is attached on the rear side of the frame of said screen a knocking device to prevent screen blinding and having an effective mesh of separation from about 28 mesh to about 65 mesh, and passing the oversize material to the final coarse concentrate fraction and the undersize to final tailings, or recycling the undersize fraction to the head of the coarse rougher flotation circuit or to the thickener at the head of the fine rougher flotation circuit.
Claim 6
Dependent Claim
33 words
A process as claimed in claim 1 wherein the anionic rEagents comprise fatty acid tall oil and fuel oil in the ratio of from about 1.5 to 1 to about 2.5 to 1.0.
Claim 7
Dependent Claim
43 words
A process as claimed in claim 1 wherein the said flotation operations are performed at controlled alkalinities wherein the pH of the flotation feed pulps are held between about 7.5 and about 9.5 with the use of caustic soda, lime or sodium carbonate.
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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) | 1976-12-31 | 1977-07-02 | 1978-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-31 | 1981-07-02 | 1982-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-31 | 1985-07-02 | 1986-01-01 | $7700.00 | Window Closed / Lapsed |