US4919207A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for drawing up special crude oil
Assignee: Mitsubishi Heavy Industries Ltd
•
Filing: 1989-05-22
•
Granted: 1990-04-24
•
Expires: 2009-05-22
Abstract
Abstract The present invention is directed to a method for drawing up a special crude oil which is characterized by comprising the steps of extracting and separating a gas oil from a crude oil containing a great deal of wax or a high-viscosity crude oil which has been drawn up through an oil well, and drawing up the crude oil containing a great deal of wax or the high-viscosity crude oil, while injecting a part of the thus separated gas oil into the oil well. For the extraction and separation of the gas oil, a recycle oil is employed.
Inventors
- 👤 Yoshiaki Ikuta
- 👤 Masayuki Moriwaki
- 👤 Masato Kaneko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:12
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/34; E21B43/40; E21B43/12; E21B43/121
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
127 words
A method for drawing up a special crude oil comprising the steps of: (1) mixing an extractant oil with a crude oil selected from the group consisting of crude oils containing a great deal of wax and high viscosity crude oils which have been drawn up from an oil well to extract a gas oil therefrom; (2) separating the mixture from step (1) into: (a) a mixture of gas oil and an extractant oil; and (b) a heavy oil; (3) separating mixture (a) obtained in step (2) into an extractant oil fraction and a gas oil fraction and injecting a part of the separated gas oil into the oil well; and (4) recycling the extractant oil obtained from step (3) into the extractant oil of step (1).
Claim 2
Independent Claim
127 words
A method for drawing up a special crude oil comprising the steps of: (1) mixing an extractant oil with a crude oil selected from the group consisting of crude oils containing a great deal of wax and high viscosity crude oils which have been drawn up from an oil well to extract a gas oil therefrom; (2) separating the mixture from step (1) into: (a) a mixture of gas oil and an extractant oil; and (b) a heavy oil; (3) separating mixture (a) obtained in step (2) into an extractant oil fraction and a gas oil fraction and injecting a part of the separated gas oil into the oil well; and (4) recycling the extractant oil obtained from step (3) into the extractant oil of step (1).
Claim 3
Dependent Claim
32 words
The method of claim 1 wherein the amount of extractant oil mixed with the crude is 0.05 to 12 times as much as the amount of a special crude oil drawn up.
Claim 4
Dependent Claim
30 words
The method of claim 1 wherein the pressure is maintained between 0 and 200 kg/cm 2 G and the temperature is kept between 0° and 450° C. in step 2).
Claim 5
Dependent Claim
20 words
The method of claim 1 wherein the temperature in step (3) is maintained higher than the temperature in step (2).
Claim 6
Dependent Claim
43 words
The method of claim 1 wherein said extractant is selected from the group consisting of aromatic hydrocarbons whose normal boiling point is 150° C. or less, straight-chain hydrocarbons with 3 to 9 carbon atoms, and monoolefin hydrocarbons with 4 to 8 carbon atoms.
References Cited (Backward Citations)
US4501445A
Cited
US4697426A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-04-23 | 1993-10-23 | 1994-04-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-04-23 | 1997-10-23 | 1998-04-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-04-23 | 2001-10-23 | 2002-04-24 | $7700.00 | Window Closed / Lapsed |