Patent US3589920A successfully refreshed from Google Patents.
US3589920A
Expired / Lapsed
US
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Process for manufacturing low alkali cements
Assignee: Dundee Cement Co
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Filing: 1969-11-17
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Granted: 1971-06-29
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Expires: 1989-11-17
Abstract
Abstract THIS APPLICATION RELATES TO PRODUCING LOW ALKALI PORTLAND CEMENTS BY ADDING DRY, PULVERIZED LIME TO THE BURNING ZONE OF THE CEMENT CLINKER FORMING KILN, TO REACT WITH THE CEMENT RAW MATERIALS AND THEREBY CONVERT THE ALKALI CONTENTS THEREOF INTO NON-CORROSIVE, ALKALI VAPORS, WHICH ARE REMOVED AS A GAS, THEREBY REDUCING THE ALKALI CONTENT OF THE CEMENT CLINKER.
Inventors
- 👤 Werner Ostberg
- 👤 Terry Patzias
- 👤 Ann Arbor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 10:37
CPC Classifications
C; C04; C04B; C04B7/00; C04B7/36; C04B7/60
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-28 | 1974-12-28 | 1975-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-28 | 1978-12-28 | 1979-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-28 | 1982-12-28 | 1983-06-29 | $7700.00 | Window Closed / Lapsed |