US3113839A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of phosphorus from sludge
Assignee: Tennessee Valley Authority
•
Filing: 1962-02-19
•
Granted: 1963-12-10
•
Expires: 1982-02-19
Abstract
No abstract record available.
Inventors
- 👤 James C Barber
- 👤 George H Megar
- 👤 Thomas S Sloan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:32
CPC Classifications
C; C01; C01B; C01B25/00; C01B25/003; B; B01; B01J; B01J2/00; B01J2/28; C01B25/01; C01B25/02; C01B25/12; C02; C02F; C02F1/00; C02F1/52
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
104 words
IN THE METHOD OF PRODUCING PHOSPHORUS BY SMELTING PHOSPHATE ROCK WITH A REDUCING AGENT IN THE PRESENCE OF SILICA AND THEREAFTER CONDENSING, COLLECTING, AND RECOVERING THE RESULTING PHOSPHORUS VAPOR UNDER WATER AND SEPARATING ACCUMULATED PHOSPHORUS-BEARING SLUDGE FROM THE RELATIVELY PURE ELEMENTAL PHOSPHORUS RESULTING FROM THE CONDENSATION OF THE PHOSPHORUS VAPOR, THE IMPROVEMENT WHICH COMPRISES ADDING SODIUM HYDROXIDE TO SAID SLUDGE AS A DISPERSING AGENT IN QUANTITY SUFFICIENT TO RAISE THE PH OF SAID SLUDGE FROM ABOUT 3.0 TO ABOUT 6.0 AGITATING THE RESULTING MIXTURE FOR A PERIOD OF ABOUT 2 TO 6 DAYS; THEREAFTER BURNING THE MIXTURE; AND RECOVERING THE RESULTING PHOSPHORUS OXIDE VAPOR.
Claim 2
Dependent Claim
104 words
IN THE METHOD OF PRODUCING PHOSPHORUS BY SMELTING PHOSPHATE ROCK WITH A REDUCING AGENT IN THE PRESENCE OF SILICA AND THEREAFTER CONDENSING, COLLECTING, AND RECOVERING THE RESULTING PHOSPHORUS VAPOR UNDER WATER AND SEPARATING ACCUMULATED PHOSPHORUS-BEARING SLUDGE FROM THE RELATIVELY PURE ELEMENTAL PHOSPHORUS RESULTING FROM THE CONDENSATION OF THE PHOSPHORUS VAPOR, THE IMPROVEMENT WHICH COMPRISES ADDING SODIUM HYDROXIDE TO SAID SLUDGE AS A DISPERSING AGENT IN QUANTITY SUFFICIENT TO RAISE THE PH OF SAID SLUDGE FROM ABOUT 3.0 TO ABOUT 6.0 AGITATING THE RESULTING MIXTURE FOR A PERIOD OF ABOUT 2 TO 6 DAYS; THEREAFTER BURNING THE MIXTURE; AND RECOVERING THE RESULTING PHOSPHORUS OXIDE VAPOR.
References Cited (Backward Citations)
US417943A
Cited
US452821A
Cited
US1334474A
Cited
US1788838A
Cited
US2039297A
Cited
US2135486A
Cited
US2267077A
Cited
US2302956A
Cited
US2744866A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1966-12-09 | 1967-06-10 | 1967-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-12-09 | 1971-06-10 | 1971-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-12-09 | 1975-06-10 | 1975-12-10 | $7700.00 | Window Closed / Lapsed |