US3980240A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Brightening of natural calcitic ores
Assignee: ECC America Inc
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Filing: 1975-04-11
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Granted: 1976-09-14
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Expires: 1995-04-11
Abstract
Abstract A method for brightening a natural calcitic ore by removal of discoloring contaminants. The ore is crushed and formed into an aqueous slurry, which slurry is then coarse-milled to produce a product wherein no more than 1 percent of the particulate matter is +325 mesh. This coarse-milled product is then subjected to a further, wet-milling step, to alter the particulate such that at least 70 percent of the particles are less than 2 microns, thereby liberating substantial quantities of the discoloring contaminants. The liberated impurities are thereupon separated from the slurry by flotation and/or by subjecting the slurry to a high intensity magnetic field.
Inventors
- 👤 Alan J. Nott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 08:08
CPC Classifications
C; C01; C01F; C01F11/00; C01F11/18; C01F11/185; C09; C09C; C09C1/00; C09C1/02; C09C1/021; C01P; C01P2004/00; C01P2004/30; C01P2004/60; C01P2004/61; C01P2004/62; C01P2006/00; C01P2006/60; C01P2006/80
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
106 words
A method for brightening and purifying a natural calcitic ore by removing discoloring contaminants therefrom, comprising the steps of: crushing said ore; forming said crushed ore into an aqueous slurry, and coarse-milling said slurry to produce a course-milled product; liberating substantial quantities of said discoloring contaminants by subjecting said coarse-milled product to a further wet-milling step to alter the particulate such that at least 70 percent of the particles are less than 2 microns; and separating the liberated contaminants from said further milled slurry, said separation being at least partially effected by subjecting said slurry to a wet magnetic separation in a high intensity magnetic field.
Claim 2
Independent Claim
106 words
A method for brightening and purifying a natural calcitic ore by removing discoloring contaminants therefrom, comprising the steps of: crushing said ore; forming said crushed ore into an aqueous slurry, and coarse-milling said slurry to produce a course-milled product; liberating substantial quantities of said discoloring contaminants by subjecting said coarse-milled product to a further wet-milling step to alter the particulate such that at least 70 percent of the particles are less than 2 microns; and separating the liberated contaminants from said further milled slurry, said separation being at least partially effected by subjecting said slurry to a wet magnetic separation in a high intensity magnetic field.
Claim 3
Dependent Claim
32 words
A method in accordance with claim 1, wherein said coarse-milling step effects comminution such that in the coarse-milled product no more than 1 percent of the particulate matter is plus 325 mesh.
Claim 4
Dependent Claim
28 words
A method in accordance with claim 1, wherein said wet-milling step alters the particulate such that at least 90 percent of the particles are less than 2 microns.
Claim 5
Dependent Claim
25 words
A method in accordance with claim 3, wherein said further milling step is effected by sand grinding of the product yielded by said coarse-milling step.
Claim 6
Dependent Claim
31 words
A method in accordance with claim 4, wherein said coarse-milling step is effected by ball-milling said slurry until no more than 1 percent of the particulate matter is plus 325 mesh.
Claim 7
Dependent Claim
21 words
A method in accordance with claim 1, further including the step of de-watering the purified slurry to yield a dry particulate.
Claim 8
Dependent Claim
23 words
A method in accordance with claim 1, wherein said separation step is at least partially effected by floating said impurities from said slurry.
Claim 9
Dependent Claim
14 words
A method in accordance with claim 7, wherein said magnetic separation follows said flotation.
Claim 10
Dependent Claim
30 words
A method in accordance with claim 1, wherein said magnetic separation is conducted by subjecting said slurry to a magnetic field having an average intensity of at least 15 kilogauss.
Claim 11
Dependent Claim
22 words
A method in accordance with claim 9, wherein said slurry is retained in the magnetic field from between 1/2 to 2 minutes.
Claim 12
Independent Claim
110 words
A method for beneficiating natural calcitic ores by removing discoloring contaminants therefrom, comprising in sequence the steps of: crushing said natural ore; forming said crushed ore into an aqueous slurry, and coarse-milling said slurry to produce a product wherein no more than 1 percent of the particulate matter is plus 325 mesh; liberating substantial quantities of said contaminants by subjecting said coarse-milled product to a further wet-milling step to alter the particulate such that at least 90 percent of the particles are less than 2 microns; and separating said liberated impurities by subjecting said slurry sequentially to a flotation step and to magnetic separation in a high intensity magnetic field.
Claim 13
Independent Claim
110 words
A method for beneficiating natural calcitic ores by removing discoloring contaminants therefrom, comprising in sequence the steps of: crushing said natural ore; forming said crushed ore into an aqueous slurry, and coarse-milling said slurry to produce a product wherein no more than 1 percent of the particulate matter is plus 325 mesh; liberating substantial quantities of said contaminants by subjecting said coarse-milled product to a further wet-milling step to alter the particulate such that at least 90 percent of the particles are less than 2 microns; and separating said liberated impurities by subjecting said slurry sequentially to a flotation step and to magnetic separation in a high intensity magnetic field.
Claim 14
Dependent Claim
25 words
A method in accordance with claim 11, wherein said magnetic separation is effected in a field having an average intensity of at least 15 kilogauss.
Claim 15
Dependent Claim
22 words
A method in accordance with claim 12, wherein said slurry is retained in said magnetic field from between 1/2 to 2 minutes.
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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) | 1979-09-14 | 1980-03-15 | 1980-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-14 | 1984-03-15 | 1984-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-14 | 1988-03-15 | 1988-09-14 | $7700.00 | Window Closed / Lapsed |