Claims
- 1. 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).
- 2. 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.
- 3. The method of claim 1 wherein the pressure is maintained between 0 and 200 kg/cm.sup.2 G and the temperature is kept between 0.degree. and 450.degree. C. in step 2).
- 4. The method of claim 1 wherein the temperature in step (3) is maintained higher than the temperature in step (2).
- 5. The method of claim 1 wherein said extractant is selected from the group consisting of aromatic hydrocarbons whose normal boiling point is 150.degree. C. or less, straight-chain hydrocarbons with 3 to 9 carbon atoms, and monoolefin hydrocarbons with 4 to 8 carbon atoms.
Priority Claims (1)
Number |
Date |
Country |
Kind |
61-146835 |
Jun 1986 |
JPX |
|
Parent Case Info
This is a continuation of application Ser. No. 065,786, filed June 24, 1987, now abandoned.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
4501445 |
Gregoli |
Feb 1985 |
|
4697426 |
Knowles, Jr. |
Oct 1987 |
|
Continuations (1)
|
Number |
Date |
Country |
Parent |
65786 |
Jun 1987 |
|