US3773658A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for regenerating used lubricating oils
Assignee: IFP Energies nouvelles
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Filing: 1971-06-04
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Granted: 1973-11-20
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Expires: 1991-06-04
Abstract
Abstract A process for regenerating used oils comprising contacting the same with a light paraffinic hydrocarbon as solvent, separating from the resulting mixture a solution of clarified oil and a residue, separating a substantial portion of the solvent from the clarified oil in a first flash zone, separating substantially the rest of the solvent from the clarified oil in a second flash zone, admixing with the residue a viscosity lowering agent, separating a substantial portion of the solvent vapors from the resulting mixture in a third flash zone and further separating substantially the rest of the solvent vapors from said residue in a fourth flash zone, condensing the solvent vapors from the first, second and fourth zones and admixing the resulting condensate with the solvent vapors from the third zone.
Inventors
- 👤 Q Vu
- 👤 F Audibert
- 👤 J Boucher
- 👤 H Deville
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 04:18
CPC Classifications
C; C10; C10M; C10M175/00; C10M175/005
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
21 words
A process as defined by claim 1 wherein the volumetric ratio of viscosity lowering agent to residue is 0.2:1 to 5:1.
Claim 2
Dependent Claim
21 words
A process as defined by claim 1 wherein the volumetric ratio of viscosity lowering agent to residue is 0.5:1 to 3:1.
Claim 3
Dependent Claim
142 words
In a process for regenerating a used lubricating oil comprising the steps of: a. contacting said oil with a liquid solvent selected from the group consisting of propane, butane, pentane and mixtures thereof; b. separating resultant contacted oil and solvent into: i. a mixture of clarified oil and solvent, and ii. a viscous residue containing solvent c. fractionating said mixture of clarified oil and solvent to form separated solvent vapor, and d. fractionating said viscous residue containing solvent to form separated solvent vapor containing entrained impurities, the improvement which comprises condensing said solvent vapor separated from said clarified oil in indirect heat exchange relationship with a coolant in a condenser, and employing resultant condensed solvent to condense by direct heat exchange contact said solvent vapor containing condensed impurities, whereby said entrained impurities are not deposited on heat exchange surfaces of a condenser.
Claim 4
Dependent Claim
46 words
A process as defined by claim 4, further comprising admixing to said viscous residue prior to said fractionating a viscosity lowering agent, said agent being a hydrocarbon cut having a viscosity of 0.5-50 centistokes at 100*C, whereby foaming and clogging of downstream fractionating equipment is reduced.
Claim 5
Dependent Claim
172 words
A process for regenerating used lubricating oils comprising contacting the used oils with a light liquid paraffinic hydrocarbon solvent; separating resulting contact mixture into a mixture of (a) clarified oil and solvent and (b) a viscous residue carrying along part of the solvent therewith, subjecting said mixture of (a) clarified oil and solvent to a first pressure release and a first step of distillation of the solvent contained therein under a first pressure of 5-25 kg/cm2, then to a second pressure release and a second step of distillation of the solvent contained therein under a second pressure of 0.9-3 kg/cm2; and admixing to said (b) viscous residue carrying along a part of the solvent, with a hydrocarbon cut having a viscosity of 0.5-50 centistokes at 100*C, and subjecting the resulting mixture of residue and hydrocarbon cut to a pressure release and a distillation of the solvent carried along therewith, wherein the latter distillation is conducted in two successive stages, a first stage at 5-25 kg/cm2 and a second stage at 0.9-3 kg/cm2.
Claim 6
Dependent Claim
96 words
A process according to claim 6, wherein both streams of solvent vapors obtained from the two pressure release and distillation of the mixture clarified oil-solvent and the stream of solvent vapors issued from the second pressure release of the residue are admixed with each other and condensed by indirect heat exchange with a coolant before being, at least partly, contacted directly with the stream of the solvent vapors issued from the first pressUre release of the residue, this direct contact resulting in the condensation of the vapors issuing from said first pressure release of the residue.
Claim 7
Dependent Claim
68 words
A process according to claim 6, wherein the stream of vapors from the second pressure release of the mixture (a) of clarified oil and solvent is preliminarily admixed to the stream of vapors from the second pressure release of the residue and the whole mixture is compressed before being admixed with the stream of vapors from the first pressure release of the mixture of clarified oil and solvent.
Claim 8
Dependent Claim
30 words
A process according to claim 6, wherein the hydrocarbon cut is used in a proportion of 0.2 to 5 parts by volume per part by volume of the viscous residue.
Claim 9
Dependent Claim
48 words
A process according to claim 6, wherein the first step of distillation of the mixture (a) of clarified oil and solvent and the first step of distillation of the solvent from the mixture of residue and hydrocarbon cut are conducted under a pressure between 10 and 20 kg/cm2.
Claim 10
Dependent Claim
15 words
A process according to claim 6, wherein the hydrocarbon cut is a fuel oil cut.
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) | 1976-11-19 | 1977-05-21 | 1977-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-19 | 1981-05-21 | 1981-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-19 | 1985-05-21 | 1985-11-20 | $7700.00 | Window Closed / Lapsed |