Claims
- 1. A process for simultaneously solvent-deasphalting and extracting a mineral oil feedstock containing asphaltic and aromatic components which comprises the steps of:
- (1) contacting said feedstock in a combination deasphalting-extracting zone with a solvent comprising a mixture of (a) NMP containing from 0-5 LV% water and (b) one or more liquid, low molecular weight C.sub.2 -C.sub.10 carbon atom hydrocarbons to form two layers or phases, an upper raffinate phase containing the desired oil, most of the hydrocarbon solvent and some NMP and a lower, extract layer or phase containing asphalt and most of the NMP;
- (2) removing the raffinate from said combination zone and heating same to a temperature ranging from between 180.degree. to 450.degree. F.;
- (3) passing said hot raffinate from step (2) to a flash zone to remove most of the hydrocarbon solvent therefrom as vapor to produce a hydrocarbon solvent-reduced raffinate;
- (4) chilling said hydrocarbon solvent-reduced raffinate to a temperature sufficiently low to produce bulk liquid-liquid immiscibility between the raffinate oil and the NMP, thereby forming two phases or layers, an oil-rich light phase and an NMP-rich heavy phase containing some oil and most of the NMP present in the raffinate formed in step (1) above;
- (5) separating the oil-rich phase from the NMP-rich phase; and
- (6) passing said NMP-rich phase back into said combination zone.
- 2. The process of claim 1 wherein said contacting step is conducted at a temperature ranging from about 70.degree. to about 350.degree. F., at a pressure ranging from about 10 to about 600 psig.
- 3. The process of claim 2 wherein said contacting step is conducted at a solvent-to-oil ratio ranging from about 50 to 800 LV% for the hydrocarbon and from about 50 to 400 LV% for the NMP.
- 4. The process of claim 3 wherein the mineral oil is a petroleum oil having an initial boiling point ranging from about 500.degree. to about 1050.degree. F. at atmospheric pressure.
- 5. The process of claim 4 wherein said raffinate is heated to a temperature ranging between about 180.degree. to 450.degree. F. before being passed to said flash zone.
- 6. The process of claim 5 wherein said flash zone operates at a temperature and pressure ranging from about 180.degree. to 450.degree. F. and 40 to 500 psig, respectively.
- 7. The process of claim 6 wherein said hydrocarbon-solvent reduced raffinate produced in said flash zone is cooled to a temperature below about 250.degree. F. before being passed to said settling zone.
- 8. The process of claim 7 wherein said oil is a resid having an initial boiling point ranging from about 700.degree. F.+ to about 1100.degree. F.+ at atmospheric pressure.
- 9. The process of claim 8 wherein said hydrocarbon solvent is propane.
- 10. The process of claim 9 wherein said NMP contains from about 0-2 LV% water.
- 11. A simultaneous solvent-deasphalting-extracting process for a heavy petroleum oil feed selected from the group consisting essentially of crude oils, atmospheric resids and vacuum resids containing both asphaltic and aromatic components, which comprises the steps of:
- (1) contacting said feed in a combination deasphalting-extracting zone, at a temperature and pressure ranging from about 120.degree.-190.degree. F. and 180-500 psig, respectively, with a solvent comprising a mixture of (a) NMP containing from 0-5 LV% water, (b) one or more liquid, low molecular weight C.sub.2 -C.sub.10 carbon atom hydrocarbons to form two layers or phases, an upper raffinate phase containing the desired oil, most of the hydrocarbon solvent and some NMP and a lower, extract layer or phase containing most of the NMP and water along with the asphaltenes and most of the aromatic and polar components of the feed;
- (2) removing the raffinate from said combination zone and heating same to a temperature ranging from between 180.degree. to 450.degree. F.;
- (3) passing said hot raffinate from step (2) to a flash zone to remove most of the hydrocarbon solvent therefrom as vapor and produce a hydrocarbon solvent-reduced raffinate;
- (4) chilling said hydrocarbon solvent-reduced raffinate to a temperature sufficiently low to produce bulk liquid-liquid immiscibility between the raffinate oil and the NMP, thereby forming two phases or layers, an oil-rich light phase and an NMP-rich heavy phase containing some oil and most of the NMP present in the raffinate formed in step (1) above;
- (5) separating the oil-rich phase from the NMP-rich phase; and
- (6) passing said NMP-rich phase back into said combination zone.
CROSS REFERENCE TO RELATED APPLICATIONS
This is a continuation-in-part of copending U.S. Ser. No. 847,014, filed on Oct. 31, 1977, which was a continuation of U.S. Ser. No. 683,376, filed on May 5, 1976, both now abandoned.
US Referenced Citations (4)
Number |
Name |
Date |
Kind |
3291718 |
Biribauer et al. |
Dec 1966 |
|
3779895 |
Wilson et al. |
Dec 1973 |
|
3779896 |
Woodle |
Dec 1973 |
|
3816295 |
Coleman et al. |
Jun 1974 |
|
Foreign Referenced Citations (1)
Number |
Date |
Country |
613,224 |
Jan 1961 |
CAX |
Continuations (1)
|
Number |
Date |
Country |
Parent |
683376 |
May 1976 |
|
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
847014 |
Oct 1977 |
|