US3878892A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vertical downward gas-driven miscible blanket flooding oil recovery process
Assignee: Texaco Inc
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Filing: 1973-05-04
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Granted: 1975-04-22
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Expires: 1993-05-04
Abstract
Abstract A vertical downward gas-driven miscible blanket oil recovery process wherein the spreading rate of the solvent blanket on top of the oil column is increased by adding to or using with the conventional solvent a high density solvent such as carbon disulfide, carbon tetrachloride or certain halogenated hydrocarbons. Sufficient dense solvent is injected along with the conventional hydrocarbon solvent to increase the density of the resulting solvent mixture to a value only slightly less than the density of the formation petroleum being displaced, so that a stable blanket will be maintained with substantially increased rate and extent of spreading of the solvent blanket on top of the oil column. The miscible blanket is displaced downward by injecting gas such as natural gas, methane, or carbon dioxide into the upper portion of the reservoir. The dense solvent may be injected before or after the conventional solvent, or the dense and conventional solvent may be injected simultaneously using dual injection strings.
Inventors
- 👤 Joseph C Allen
- 👤 Jack F Tate
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:08
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/16; E21B43/166; E21B43/168
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
149 words
A VERTICALLY DOWNWARD, MISCIBLE BLANKET FLOODING TECHNIQUE FOR RECOVERING PETROLEUM FROM A SUBTERRANEAN PETROLEUM CONTAINING FORMATION PENETRATED BY AT LEAST TWO INJECTION WELLS IN FLUID COMMUNICATION WITH THE UPPER PORTION OF THE FORMATION AND BY AT LEAST ONE PRODUCTION WELL IN FLUID COMMUNICATION WITH THE LOWER PORTION OF THE FORMATION COMPRISING: A. INJECTING A CONVENTIONAL SOLVENT FOR PETROLEUM; B. INJECTING A DENSE SOLVENT FOR PETROLEUM, SAID DENSE SOLVENT BEING DENSER THAN THE FORMATION PETROLEUNM, SAID CONVENTIONAL SOLVENT AND SAID DENSE SOLVENT BEING INJECTED ESSENTIALLY SIMULTANEOUSLY IN SEPARATE INJECTION WELLS, THE CONVENTIONAL SOLVENT AND DENSE SOLVENT FORMING A MIXTURE HAVING A DENSITY GREATER THAN THE CONVENTIONAL SOLVENT AND LESS THAN THE FORMATION PETROLEUM; C. INJECTING A GASEOUS DRIVE FLUID INTO THE UPPER PORTION OF THE FORMATION TO DISPLACE THE SOLVENTS AND PETROLEUM DOWNWARD THROUGH THE FORMATION; AND D. RECOVERING FORMATION PETROLEUM AND SOLVENTS FROM THE LOWER PORTION OF THE FORMATION.
Claim 2
Dependent Claim
149 words
A VERTICALLY DOWNWARD, MISCIBLE BLANKET FLOODING TECHNIQUE FOR RECOVERING PETROLEUM FROM A SUBTERRANEAN PETROLEUM CONTAINING FORMATION PENETRATED BY AT LEAST TWO INJECTION WELLS IN FLUID COMMUNICATION WITH THE UPPER PORTION OF THE FORMATION AND BY AT LEAST ONE PRODUCTION WELL IN FLUID COMMUNICATION WITH THE LOWER PORTION OF THE FORMATION COMPRISING: A. INJECTING A CONVENTIONAL SOLVENT FOR PETROLEUM; B. INJECTING A DENSE SOLVENT FOR PETROLEUM, SAID DENSE SOLVENT BEING DENSER THAN THE FORMATION PETROLEUNM, SAID CONVENTIONAL SOLVENT AND SAID DENSE SOLVENT BEING INJECTED ESSENTIALLY SIMULTANEOUSLY IN SEPARATE INJECTION WELLS, THE CONVENTIONAL SOLVENT AND DENSE SOLVENT FORMING A MIXTURE HAVING A DENSITY GREATER THAN THE CONVENTIONAL SOLVENT AND LESS THAN THE FORMATION PETROLEUM; C. INJECTING A GASEOUS DRIVE FLUID INTO THE UPPER PORTION OF THE FORMATION TO DISPLACE THE SOLVENTS AND PETROLEUM DOWNWARD THROUGH THE FORMATION; AND D. RECOVERING FORMATION PETROLEUM AND SOLVENTS FROM THE LOWER PORTION OF THE FORMATION.
Claim 3
Dependent Claim
149 words
A vertically downward, miscible blanket flooding technique for recovering petroleum from a subterranean petroleum containing formation penetrated by at least two injection wells in fluid communication with the upper portion of the formation and by at least one production well in fluid communication with the lower portion of the formation comprising: a. injecting a conventional solvent for petroleum; b. injecting a dense solvent for petroleum, said dense solvent being denser than the formation petroleum, said conventional solvent and said dense solvent being injected essentially simultaneously in separate injection wells, the conventional solvent and dense solvent forming a mixture having a density greater than the conventional solvent and less than the formation petroleum; c. injecting a gaseous drive fluid into the upper portion of the formation to displace the solvents and petroleum downward through the formation; and d. recovering formation petroleum and solvents from the lower portion of the formation.
Claim 4
Dependent Claim
149 words
A vertically downward, miscible blanket flooding technique for recovering petroleum from a subterranean petroleum containing formation penetrated by at least two injection wells in fluid communication with the upper portion of the formation and by at least one production well in fluid communication with the lower portion of the formation comprising: a. injecting a conventional solvent for petroleum; b. injecting a dense solvent for petroleum, said dense solvent being denser than the formation petroleum, said conventional solvent and said dense solvent being injected essentially simultaneously in separate injection wells, the conventional solvent and dense solvent forming a mixture having a density greater than the conventional solvent and less than the formation petroleum; c. injecting a gaseous drive fluid into the upper portion of the formation to displace the solvents and petroleum downward through the formation; and d. recovering formation petroleum and solvents from the lower portion of the formation.
Claim 5
Dependent Claim
31 words
A method as recited in claim 1 wherein the petroleum containing formation is tar sand and the dense solvent is carbon disulfide or a mixture of carbon disulfide and carbon tetrachloride.
Claim 6
Dependent Claim
34 words
A method as recited in claim 1 wherein the dense solvent is selected from the group consisting of carbon disulfide, carbon tetrachloride, and halogenated hydrocarbons which are essentially insoluble in and unreactive with water.
Claim 7
Dependent Claim
14 words
A method as recited in claim 3 wherein the dense solvent is carbon disulfide.
Claim 8
Dependent Claim
14 words
A method as recited in claim 3 wherein the dense solvent is carbon tetrachloride.
Claim 9
Dependent Claim
30 words
A method as recited in claim 3 wherein the halogenated hydrocarbon which is essentially insoluble in and unreactive with water is selected from the group consisting of trichloromethane and chlorobenzene.
Claim 10
Dependent Claim
13 words
A method as recited in claim 6 wherein the halogenated hydrocarbon is trichloromethane.
Claim 11
Dependent Claim
13 words
A method as recited in claim 6 wherein the halogenated hydrocarbon is chlorobenzene.
Claim 12
Dependent Claim
20 words
A method as recited in claim 1 wherein the dense solvent is a mixture of carbon disulfide and carbon tetrachloride.
Claim 13
Dependent Claim
17 words
A method as recited in claim 1 wherein the conventional solvent also contains an aromatic hydrocarbon solvent.
Claim 14
Dependent Claim
13 words
A method as recited in claim 10 wherein the aromatic hydrocarbon is benzene.
Claim 15
Dependent Claim
13 words
A method as recited in claim 10 wherein the aromatic hydrocarbon is toluene.
Claim 16
Dependent Claim
41 words
A method as recited in claim 1 wherein sufficient dense solvent is injected along with the conventional solvent to produce a mixture having a density equal to from about 80 to about 95 percent of the density of the formation petroleum.
Claim 17
Dependent Claim
15 words
A method as recited in claim 1 wherein the drive fluid is predominantly natural gas.
Claim 18
Dependent Claim
14 words
A method as recited in claim 1 wherein the drive fluid is predominantly methane.
Claim 19
Dependent Claim
14 words
A method as recited in claim 1 wherein the drive fluid is carbon dioxide.
Claim 20
Dependent Claim
60 words
A method as recited in claim 1 wherein a mixture of solvent and formation petroleum is produced near the conclusion of the vertically downward miscible flood and this mixture is subjected on the surface to the additional steps of, a. separating the solvent from the produced mixture of petroleum and solvent by distillation, and b. compressing and reliquefying the solvent.
Claim 21
Dependent Claim
195 words
A vertically downward, miscible blanket flooding method for recovering petroleum from a subterranean, petroleum containing formation penetrated by at least one injection well in fluid communication with the upper portion of the formation and by at least one production well in fluid communication with the lower portion of the formation comprising: a. injecting a hydrocarbon solvent for petroleum into the formation; b. injecting a dense solvent for petroleum into the formation, said dense solvent being denser than the formation petroleum, wherein repetitive cycles in which first said hydrocarbon solvent and then said dense solvent are injected into the injection well so that said solvents mix in the injection string and enter the formation as a mixture, the ratio of the volume of said dense solvent to volume of said hydrocarbon solvent being selected to form a mixture having a density less than the density of the formation petroleum; and c. injecting a gaseous drive fluid into the upper portion of the formation to displace the solvent and petroleum downward through the petroleum formation; and d. producing the formation petroleum and solvents from the production well in fluid communication with the lower portion of the formation.
Claim 22
Dependent Claim
195 words
A vertically downward, miscible blanket flooding method for recovering petroleum from a subterranean, petroleum containing formation penetrated by at least one injection well in fluid communication with the upper portion of the formation and by at least one production well in fluid communication with the lower portion of the formation comprising: a. injecting a hydrocarbon solvent for petroleum into the formation; b. injecting a dense solvent for petroleum into the formation, said dense solvent being denser than the formation petroleum, wherein repetitive cycles in which first said hydrocarbon solvent and then said dense solvent are injected into the injection well so that said solvents mix in the injection string and enter the formation as a mixture, the ratio of the volume of said dense solvent to volume of said hydrocarbon solvent being selected to form a mixture having a density less than the density of the formation petroleum; and c. injecting a gaseous drive fluid into the upper portion of the formation to displace the solvent and petroleum downward through the petroleum formation; and d. producing the formation petroleum and solvents from the production well in fluid communication with the lower portion of the formation.
Claim 23
Dependent Claim
36 words
A method as recited in claim 18 wherein said dense solvent is selected from the group consisting of carbon disulfide, halogenated hydrocarbons which are essentially insoluble in and unreactive with water, carbon tetrachloride, and mixtures thereof.
Claim 24
Dependent Claim
14 words
A method as recited in claim 18 wherein the dense solvent is carbon disulfide.
Claim 25
Dependent Claim
173 words
A vertically downward, miscible blanket flooding method for recovering petroleum from a subterranean, petroleum containing formation penetrated by at least one injection well completed with tubing inside casing with an annular space between tubing and casing to define two separate injection means, both means being in fluid communication with the upper portion of the formation, the formation being penetrated by at least one production well in fluid communication with the lower portion of the formation, comprising: a. injecting a hydrocarbon solvent for petroleum into one of the injection means; b. injecting a dense solvent for petroleum which is denser than the formation petroleum into the other injection means, the ratio of said hydrocarbon solvent volume to said dense solvent volume being chosen to form a mixture having a density less than the density of the formation petroleum; c. injecting a gaseous drive fluid into the upper portion of the formation to displace the solvent and petroleum downward throUgh the formation; and d. producing the formation petroleum and said solvents from the production well.
Claim 26
Dependent Claim
173 words
A vertically downward, miscible blanket flooding method for recovering petroleum from a subterranean, petroleum containing formation penetrated by at least one injection well completed with tubing inside casing with an annular space between tubing and casing to define two separate injection means, both means being in fluid communication with the upper portion of the formation, the formation being penetrated by at least one production well in fluid communication with the lower portion of the formation, comprising: a. injecting a hydrocarbon solvent for petroleum into one of the injection means; b. injecting a dense solvent for petroleum which is denser than the formation petroleum into the other injection means, the ratio of said hydrocarbon solvent volume to said dense solvent volume being chosen to form a mixture having a density less than the density of the formation petroleum; c. injecting a gaseous drive fluid into the upper portion of the formation to displace the solvent and petroleum downward throUgh the formation; and d. producing the formation petroleum and said solvents from the production well.
Claim 27
Dependent Claim
36 words
A method as recited in claim 21 wherein the dense solvent is selected from the group consisting of carbon disulfide, halogenated hydrocarbons which are essentially insoluble in and unreactive with water, carbon tetrachloride, and mixtures thereof.
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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) | 1978-04-21 | 1978-10-21 | 1979-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-21 | 1982-10-21 | 1983-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-21 | 1986-10-21 | 1987-04-22 | $7700.00 | Window Closed / Lapsed |