US3773473A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Beneficiation and hot briquetting of phosphate ores by removing -400 mesh fines
Assignee: FMC Corp
•
Filing: 1969-10-02
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Granted: 1973-11-20
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Expires: 1989-10-02
Abstract
Abstract A beneficiated, calcined, phosphate agglomerate, useful as a phosphorus furnace feed is produced by crushing phosphate shale to substantially - 1/2 inch, heating and calcining the crushed shale in a fluidized bed, removing a relatively phosphorus-poor fine fraction overhead from a relatively phosphorus-rich coarse fraction remaining in the fluidized bed, withdrawing a portion of the heated, coarse fraction from the fluidized bed and hot briquetting it under pressure to form strong, calcined phosphate agglomerates.
Inventors
- 👤 R Howard
- 👤 J Sullivan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:06
CPC Classifications
C; C01; C01B; C01B25/00; C01B25/01; C22; C22B; C22B1/00; C22B1/14; C22B1/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
20 words
Process of claim 1 wherein the fluidized bed is maintained at a temperature of from about 1500*F. to about 2200*F.
Claim 2
Dependent Claim
19 words
Process of claim 1 wherein substantially all of the phosphate ore is crushed to - 1/4 inch in diameter.
References Cited (Backward Citations)
CA481706A
Cited
CA676711A
Cited
US2562718A
Cited
US2971832A
Cited
US3076248A
Cited
US3364008A
Cited
US3522338A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-19 | 1977-05-21 | 1977-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-19 | 1981-05-21 | 1981-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-19 | 1985-05-21 | 1985-11-20 | $7700.00 | Window Closed / Lapsed |