US4512878A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Used oil re-refining
Assignee: ExxonMobil Technology and Engineering Co
•
Filing: 1983-02-16
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Granted: 1985-04-23
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Expires: 2003-02-16
Abstract
Abstract Used oils, especially used lubricating oils which are normally considered waste and are discarded or burned, are reclaimed for reuse by a re-refining procedure involving the steps of: (a) heat soaking the used oil; (b) distilling the heat soaked oil; (c) passing the distillate through a guard bed of activated material; (d) hydrotreating the guard bed treated distillate under standard hydrotreating conditions. If the used oil to be re-refined contains a quantity of water and/or fuel fraction which the practioner considers sufficiently large to be detrimental, the used oil may be subjected to a dewatering/defueling step prior to being heat soaked.
Inventors
- 👤 Lloyd E. Reid
- 👤 Keith C. Yao
- 👤 Douglas G. Ryan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:31
CPC Classifications
C; C10; C10M; C10M175/00; C10M175/02
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
158 words
A process for re-refining used oils so as to produce a basestock oil essentially equivalent in quality to basestock produced from virgin crude oil which process comprises the steps of: (A) heat soaking the used oil at from 250° C.-340° C. for a time sufficient to maximize halide, phosphorus and sludge precursors removal by conversion of these materials into materials which go with the residue during the distillation step; (B) passing the entire contents of the heat soaker directly to coke resistant distillation means; (C) distilling the contents from the heat soaker under conditions of residence time, temperature and pressure selected to produce a distillate whose end point is essentially that of the target stock product and a residue; (D) passing the distillate through a guard bed of activated material capable of removing residual phosphorus, halides and sludge from the distillate; (E) hydrotreating the guard bed treated distillate under standard hydrotreating conditions, thereby producing a re-refined base stock.
Claim 2
Dependent Claim
158 words
A process for re-refining used oils so as to produce a basestock oil essentially equivalent in quality to basestock produced from virgin crude oil which process comprises the steps of: (A) heat soaking the used oil at from 250° C.-340° C. for a time sufficient to maximize halide, phosphorus and sludge precursors removal by conversion of these materials into materials which go with the residue during the distillation step; (B) passing the entire contents of the heat soaker directly to coke resistant distillation means; (C) distilling the contents from the heat soaker under conditions of residence time, temperature and pressure selected to produce a distillate whose end point is essentially that of the target stock product and a residue; (D) passing the distillate through a guard bed of activated material capable of removing residual phosphorus, halides and sludge from the distillate; (E) hydrotreating the guard bed treated distillate under standard hydrotreating conditions, thereby producing a re-refined base stock.
Claim 3
Dependent Claim
19 words
The process of claim 1 wherein the used oil subjected to the re-refining process is a used lube oil.
Claim 4
Dependent Claim
18 words
The process of claim 1, wherein the heat soaking step is preceded by a dewatering and defueling step.
Claim 5
Dependent Claim
15 words
The process of claim 1 wherein the dewatering and defueling step is practiced using distillation.
Claim 6
Dependent Claim
26 words
The process of claim 1 wherein the heat soaking step is conducted at a temperature of about 280° to 320° C. for from about 15-120 minutes.
Claim 7
Dependent Claim
21 words
The process of claim 1, 3 or 5 wherein the heat soaking is conducted for from about 30 to 120 minutes.
Claim 8
Dependent Claim
24 words
The process of claim 6 wherein the distillation is conducted in a thin film evaporator, a wiped film evaporator or a cyclonic distillation tower.
Claim 9
Dependent Claim
20 words
The process of claim 1 wherein the guard bed is a bed of Fuller's Earth, charcoal, lime or activated alumina.
Claim 10
Dependent Claim
15 words
The process of claim 7 wherein the guard bed is a bed of activated alumina.
Claim 11
Dependent Claim
36 words
The process of claim 7 wherein the guard bed is run at a temperature of about 180° to 340° C., a pressure of about atmospheric to 5 MPa, a LSHV of about 0.5 to 2 v/v/hr.
Claim 12
Dependent Claim
40 words
The process of claim 10 wherein the hydrotreating is conducted at a temperature of from about 260°-400° C., a hydrogen pressure of about 3-11 MPa, a LSHV of about 0.5-4, and a gas rate of about 1.5-15 kmol/m 3 .
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-04-22 | 1988-10-22 | 1989-04-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-22 | 1992-10-22 | 1993-04-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-22 | 1996-10-22 | 1997-04-23 | $7700.00 | Window Closed / Lapsed |