US4756369A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of viscous oil recovery
Assignee: Mobil Oil AS
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Filing: 1986-11-26
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Granted: 1988-07-12
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Expires: 2006-11-26
Abstract
Abstract A process for recovering viscous heavy oil from a substantially shallow reservoir having a low temperature and pressure. Following a steam flood, liquid carbon dioxide is injected into the reservoir where said carbon dioxide remains in its liquid state. Afterwards, a spacer volume of a vaporizable drive fluid is injected into the reservoir behind said carbon dioxide. Subsequently, steam injection is commenced which causes the drive fluid to vaporize and the liquid carbon dioxide to gasify. Vaporization of the drive fluid along with gasification of the carbon dioxide causes a pressure increase in the formation allowing the thinned oil to be removed therefrom.
Inventors
- 👤 Alfred R. Jennings, Jr.
- 👤 Edwin T. Strom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:48
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/16; E21B43/164; E21B43/24
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
125 words
A process for recovering viscous oil from a substantially shallow reservoir comprising: (a) injecting steam into at least one wellbore which steam is sufficient for making the oil less viscous so that it flows to at least one production well; (b) injecting thereafter liquid carbon dioxide into said formation where a substantial portion of said carbon dioxide remains in its liquid state; (c) injecting a spacer volume of a vaporizable drive fluid into said reservoir; and (d) injecting steam behind said drive fluid which causes said drive fluid to vaporize and the liquid carbon dioxide to flash to a gaseous phase thereby increasing the pressure in said reservoir and thinning the oil to facilitate its removal from said reservoir by at least one production well.
Claim 2
Dependent Claim
125 words
A process for recovering viscous oil from a substantially shallow reservoir comprising: (a) injecting steam into at least one wellbore which steam is sufficient for making the oil less viscous so that it flows to at least one production well; (b) injecting thereafter liquid carbon dioxide into said formation where a substantial portion of said carbon dioxide remains in its liquid state; (c) injecting a spacer volume of a vaporizable drive fluid into said reservoir; and (d) injecting steam behind said drive fluid which causes said drive fluid to vaporize and the liquid carbon dioxide to flash to a gaseous phase thereby increasing the pressure in said reservoir and thinning the oil to facilitate its removal from said reservoir by at least one production well.
Claim 3
Dependent Claim
24 words
The process as recited in claim 1 where in step (c) said drive fluid comprises water, liquefied petroleum gas, or butane/butene and mixtures thereof.
Claim 4
Dependent Claim
16 words
The process as recited in claim 1 where the reservoir pressure is increased at least twice.
Claim 5
Dependent Claim
19 words
The process as recited in claim 1 where the reservoir temperature is from about 60° to about 90° F.
Claim 6
Dependent Claim
26 words
The process as recited in claim 1 where the wells are placed into the formation to a depth of from about 500 to about 8000 feet.
Claim 7
Dependent Claim
14 words
The process as recited in claim 1 where steps (a) through (d) are repeated.
Claim 8
Dependent Claim
113 words
A process for recovering viscous oil from a substantially shallow reservoir where following a steam flood oil is produced from said reservoir, the improvement comprising: (a) injecting after the steam flood liquid carbon dioxide into said formation where a substantial portion of said carbon dioxide remains in its liquid state; (b) injecting thereafter a spacer volume of a vaporizable drive fluid into said reservoir; and (c) injecting steam behind said drive fluid which causes said drive fluid to vaporize thereby flashing the liquid carbon dioxide to a gaseous phase which causes the reservoir pressure to increase while thinning the oil, thereby facilitating its removal from said reservoir by at least one production well.
Claim 9
Dependent Claim
113 words
A process for recovering viscous oil from a substantially shallow reservoir where following a steam flood oil is produced from said reservoir, the improvement comprising: (a) injecting after the steam flood liquid carbon dioxide into said formation where a substantial portion of said carbon dioxide remains in its liquid state; (b) injecting thereafter a spacer volume of a vaporizable drive fluid into said reservoir; and (c) injecting steam behind said drive fluid which causes said drive fluid to vaporize thereby flashing the liquid carbon dioxide to a gaseous phase which causes the reservoir pressure to increase while thinning the oil, thereby facilitating its removal from said reservoir by at least one production well.
Claim 10
Dependent Claim
24 words
The process as recited in claim 7 where in step (b) said drive fluid comprises water, liquefied petroleum gas, or butane/butene and mixtures thereof.
Claim 11
Dependent Claim
16 words
The process as recited in claim 7 where the reservoir pressure is increased at least twice.
Claim 12
Dependent Claim
19 words
The process as recited in claim 7 where the reservoir temperature is from about 60° to about 90° F.
Claim 13
Dependent Claim
26 words
The process as recited in claim 7 where the wells are placed into the formation to a depth of from about 500 to about 8000 feet.
Claim 14
Dependent Claim
14 words
The process as recited in claim 7 where steps (a) through (c) are repeated.
Claim 15
Dependent Claim
26 words
The process as recited in claim 7 where at least one injection and one production well are utilized to remove the thinned oil from said reservoir.
Claim 16
Dependent Claim
29 words
The process as recited in claim 7 where one well alone is used for both the injection and the production well to remove the thinned oil from said reservoir.
Claim 17
Dependent Claim
147 words
A process for recovering viscous oil from a substantially shallow reservoir having a substantially low reservoir temperature and pressure comprising: (a) injecting steam into said reservoir which reservoir has a temperature of about 50° to about 150° F. via at least one wellbore which steam is sufficient to make the oil less viscous and flow to at least one production well; (b) injecting liquid carbon dioxide into the formation until substantially all of said carbon dioxide within said reservoir is in its liquid state; (c) injecting a spacer volume of a vaporizable drive fluid into said reservoir; and (d) injecting steam behind said drive fluid which causes said drive fluid to vaporize and the liquid carbon dioxide to flash to a gaseous phase thereby increasing the pressure in said reservoir and thinning the oil to facilitate its removal from said reservoir by at least one production well.
Claim 18
Dependent Claim
147 words
A process for recovering viscous oil from a substantially shallow reservoir having a substantially low reservoir temperature and pressure comprising: (a) injecting steam into said reservoir which reservoir has a temperature of about 50° to about 150° F. via at least one wellbore which steam is sufficient to make the oil less viscous and flow to at least one production well; (b) injecting liquid carbon dioxide into the formation until substantially all of said carbon dioxide within said reservoir is in its liquid state; (c) injecting a spacer volume of a vaporizable drive fluid into said reservoir; and (d) injecting steam behind said drive fluid which causes said drive fluid to vaporize and the liquid carbon dioxide to flash to a gaseous phase thereby increasing the pressure in said reservoir and thinning the oil to facilitate its removal from said reservoir by at least one production well.
Claim 19
Dependent Claim
16 words
The process as recited in claim 15 where the reservoir pressure is increased at least twice.
Claim 20
Dependent Claim
19 words
The process as recited in claim 15 where the reservoir temperature is from about 60° to about 90° F.
Claim 21
Dependent Claim
26 words
The process as recited in claim 15 where the wells are placed into the formation to a depth of from about 500 to about 8000 feet.
Claim 22
Dependent Claim
14 words
The process as recited in claim 15 where steps (a) through (d) are repeated.
References Cited (Backward Citations)
US3262498A
Cited
US3459265A
Cited
US3838738A
Cited
US3927716A
Cited
US4004636A
Cited
US4224992A
Cited
US4441555A
Cited
US4565249A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-07-12 | 1992-01-11 | 1992-07-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-12 | 1996-01-11 | 1996-07-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-12 | 2000-01-11 | 2000-07-12 | $7700.00 | Window Closed / Lapsed |