US3149964A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Removal of zinc from lead-containing flue dust
Assignee: GEA Group AG
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Filing: 1961-11-27
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Granted: 1964-09-22
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Expires: 1981-11-27
Abstract
No abstract record available.
Inventors
- 👤 Schwartz Werner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 05:49
CPC Classifications
C; C22; C22B; C22B7/00; C22B7/02; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
97 words
METHOD OF EXTRACTING LEAD FROM SULFIDIC LEAD ORES CONTAINING ZINC WHICH COMPRISES SIMULTANEOUSLY ROASTING AND SINTERING THE ORE IN AN OXYGEN ATMOSPHERE, SUBSEQUENTLY MELTING DOWN THIS SINTERED PRODUCT IN A MELTING FURNACE WHEREBY THE SINTERED PRODUCT IS CONVERTED INTO METALLIC LEAD, A SLAG, VOLATILE SO2 AND A FLUE DUCT CONTAINING ZINC AND LEAD, WASHING THE FLUE DUST WITH A SOLUTION OF SULFUROUS ACID WHICH DISSOLVES THE ZINC COMPONENT OF THE FLUE DUST BUT DOES NOT DISSOLVE THE LEAD COMPONENT, AND RECYCLING HTE UNDISSOLVED FLUE DUCT FROM WHICH THE ZINC HAS BEEN WASHED OUT INTO THE SINTERING PROCESS.
Claim 2
Dependent Claim
97 words
METHOD OF EXTRACTING LEAD FROM SULFIDIC LEAD ORES CONTAINING ZINC WHICH COMPRISES SIMULTANEOUSLY ROASTING AND SINTERING THE ORE IN AN OXYGEN ATMOSPHERE, SUBSEQUENTLY MELTING DOWN THIS SINTERED PRODUCT IN A MELTING FURNACE WHEREBY THE SINTERED PRODUCT IS CONVERTED INTO METALLIC LEAD, A SLAG, VOLATILE SO2 AND A FLUE DUCT CONTAINING ZINC AND LEAD, WASHING THE FLUE DUST WITH A SOLUTION OF SULFUROUS ACID WHICH DISSOLVES THE ZINC COMPONENT OF THE FLUE DUST BUT DOES NOT DISSOLVE THE LEAD COMPONENT, AND RECYCLING HTE UNDISSOLVED FLUE DUCT FROM WHICH THE ZINC HAS BEEN WASHED OUT INTO THE SINTERING PROCESS.
References Cited (Backward Citations)
US715024A
Cited
US2797158A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-09-22 | 1968-03-23 | 1968-09-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-09-22 | 1972-03-23 | 1972-09-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-09-22 | 1976-03-23 | 1976-09-22 | $7700.00 | Window Closed / Lapsed |