US4033859A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermal treatment of used petroleum oils
Assignee: GOLDEN BEAR ACQUISITION CORP
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Filing: 1975-04-24
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Granted: 1977-07-05
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Expires: 1995-04-24
Abstract
Abstract Used oil, such as automotive crankcase oil drainings from internal combustion engines, are pretreated by heating to above about 400°-800° F, and preferably between 600°-750° F, while an essentially liquid phase system is maintained at a pressure of between 500-3500 p.s.i.g., preferably between 2000-3500 p.s.i.g., for between 15-60 minutes, the contact time being even shorter at higher temperatures. A sludge which contains contaminants, such as insoluble degradation products, metallic compounds, and water, is separated preferably by centrifugation, leaving a substantially ashless oil ready for additional refinement to a high quality lubricating oil, or it may be used, per se, as a fuel oil.
Inventors
- 👤 Donald Douglas Davidson
- 👤 Bjorn I. Engesvik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:27
CPC Classifications
C; C10; C10M; C10M175/00; C10M175/0025
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
47 words
An improved process in the recycling of used automotive crankcase oil comprising heating said oil in an essentially liquid state at a temperature of between about 400°-800° F. under a pressure of about 500-3500 p.s.i.g. and thereafter separating the formed sludge from the substantially ashless oil product.
Claim 2
Dependent Claim
47 words
An improved process in the recycling of used automotive crankcase oil comprising heating said oil in an essentially liquid state at a temperature of between about 400°-800° F. under a pressure of about 500-3500 p.s.i.g. and thereafter separating the formed sludge from the substantially ashless oil product.
Claim 3
Dependent Claim
19 words
A process as in claim 1 wherein the temperature is about 600°-750° F. and the pressure, about 2000-3500 p.s.i.g.
Claim 4
Dependent Claim
13 words
A process as in claim 1, wherein the sludge is separated by centrifuging.
Claim 5
Dependent Claim
16 words
A process as in claim 1, wherin the reaction is continued for less than two hours.
Claim 6
Dependent Claim
18 words
A process as in claim 2, wherein the reaction is continued for between about 15 to 60 minutes.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-04 | 1981-01-03 | 1981-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-04 | 1985-01-03 | 1985-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-04 | 1989-01-03 | 1989-07-05 | $7700.00 | Window Closed / Lapsed |