Patent US3731801A successfully refreshed from Google Patents.
US3731801A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water purification
Assignee: Texaco Inc
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Filing: 1971-03-15
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Granted: 1973-05-08
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Expires: 1991-03-15
Abstract
Abstract Method of separating from hard water dissolved mineral hardness constituents whose solubility varies inversely with temperature, in which the water temperature is raised by direct, preferably cocurrent contact with a preheated stream of liquid hydrocarbon oil, to a temperature sufficient to precipitate hardness constituents but below the temperature at which the hot oil will extract water, and at a pressure sufficient to maintain the oil and water in liquid phase.
Inventors
- 👤 H Hess
- 👤 F Guptill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:19
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/02; C02F1/04; C02F1/10; C02F1/042; Y; Y10; Y10S; Y10S159/00; Y10S159/17; Y10S159/33; Y10S203/00; Y10S203/11
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
14 words
The method of claim 1 wherein said second temperature is not substantially above 700*F.
References Cited (Backward Citations)
US3305456A
Cited
US3392089A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-07 | 1976-11-06 | 1977-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-07 | 1980-11-06 | 1981-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-07 | 1984-11-06 | 1985-05-08 | $7700.00 | Window Closed / Lapsed |