EP0037699A2
Expired / Lapsed
EP
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Polymer microemulsion complexes and their use for the enhanced recovery of oil
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1981-03-31
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Granted: —
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Expires: 2001-03-31
Abstract
Abstract A polymer-microemulsion complex useful for the enhanced recovery of crude oil is disclosed. The polymer is polyethylene oxide of polyvinyl pyrrolidone and interacts with the surfactant of the microemulsion to form a physical association. The resulting complex is characterized by the complexation energy of at least 2 Kcal/mole. The polymer microemulsion complexes are stable at high salinity, reduce adsorption and retention by the formation, lower interfacial tension, achieve retentions as low as 0.1 mg surfactant/gm sand at high salinity and provide for early banking, as well as high recovery of oil. Enhanced oil recovery fluids using the polymer microemulsion complexes exhibit similar properties.
Inventors
- 👤 Nathan Harvey Canter
- 👤 Max Leo Robbins
- 👤 Edward George Baker
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 07:02
CPC Classifications
C; C09; C09K; C09K23/00; C09K23/08; C08; C08J; C08J3/00; C08J3/02; C08J3/09; C09K8/00; C09K8/58; C09K8/588
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
90 words
A stabilized microemulsion system containing a polymer-microemulsion complex which comprises: (a) a microemulsion, said microemulsion including as components: (1) an oil (2) water having up to 25% by weight of dissolved inorganic salts; and (3) an amount greater than the critical micelle concentration of at least one surfactant balanced to form the microemulsion complex; and (b) from 0.1 to 10% by weight, based on the microemulsion of a polar polymer capable of forming a polymer-microemulsion complex, the polymer-microemulsion complex being characterized by a complexation energy of at least 2 Kcal/mole.
Claim 2
Dependent Claim
90 words
A stabilized microemulsion system containing a polymer-microemulsion complex which comprises: (a) a microemulsion, said microemulsion including as components: (1) an oil (2) water having up to 25% by weight of dissolved inorganic salts; and (3) an amount greater than the critical micelle concentration of at least one surfactant balanced to form the microemulsion complex; and (b) from 0.1 to 10% by weight, based on the microemulsion of a polar polymer capable of forming a polymer-microemulsion complex, the polymer-microemulsion complex being characterized by a complexation energy of at least 2 Kcal/mole.
Claim 3
Dependent Claim
20 words
A microemulsion system according to claim 1 wherein the polar polymer is polyethylene oxide, polyvinyl pyrrolidone or a copolymer thereof.
Claim 4
Dependent Claim
23 words
A microemulsion system according to claim 2 wherein the polyethylene oxide is a branched condensation product of polyethylene oxide, bisphenol A and/or epichlorohydrin.
Claim 5
Dependent Claim
38 words
A microemulsion system according to any one of the preceding claims wherein the microemulsion contains from 0.3 to 98 wt. % component (1), 1 to 99 wt. % component (2), and 0.2 to 15 wt. % component (3).
Claim 6
Dependent Claim
27 words
A microemulsion system according to claim 4 wherein the microemulsion contains from L to 14 wt. % based on water of dissolved inorganic salts of component (2).
Claim 7
Dependent Claim
22 words
A microemulsion system according to any one of the preceding claims wherein the complexation energy is from about 5 to 15 Kcal/mole.
Claim 8
Dependent Claim
31 words
A microemulsion system according to any one of the preceding claims wherein component (3) is a mixture of an anionic surfactant with at least one other anionic, nonionic or cationic surfactant.
Claim 9
Dependent Claim
41 words
A microemulsion system according to claim 7 wherein the anionic surfactant is a sulphonate or sulphate, the non-ionic surfactant is an ethoxylated alkanol or an ethoxylated phenol and the cationic surfactant is an alkylamine, ethoxylated alkylamine or quaternary ammonium salt thereof.
Claim 10
Dependent Claim
95 words
A microemulsion system according to claim 8 wherein the sulphonate has the formula: where R 1 is C 8 to C 25 aliphatic, C 14 to C 36 alkaryl or R 2 - (OCH 2 CH 2 ) n where R has the same definition as R 1 and n is an integer of from 1 to 60 and Y is hydrogen, an alkali metal cation or N(R 3 ) ⊕ 4 where each R 3 is independently hydrogen, alkyl of 1 to 4 carbon atoms or hydroxy alkyl of 1 to 4 carbon atoms.
Claim 11
Dependent Claim
92 words
A microemulsion system according to claim 8 wherein the sulphate has the formula: where R 4 is C8 to C 25 aliphatic, C 14 to C38 alkaryl or R J - (OCH 2 CH 2 ) n where R 5 has the same definition as R 4 and n is an integer of from 1 to 60 and Y is hydrogen, alkali metal cation or N(R 3 ) ⊕ 4 where each R 3 is independently hydrogen, alkyl of 1 to 4 carbon atoms or hydroxyalkyl of 1 to 4 carbon atoms.
Claim 12
Dependent Claim
74 words
A microemulsion system according to claim 8 wherein nonionic consurfac t an t is an ethoxylated C 8 to C 25 alkanol or an ethoxylated phenol of the formula: where R 6 is C 1 to C 24 alkyl, A is benzene, P is 2 to 60, q is 1 or 2 and r is 1 to 5 with the proviso that when R is 1, R 6 is at least C 8 .
Claim 13
Dependent Claim
33 words
A microemulsion system according to claim 8 wherein the cationic cosurfactant has the formula: where m is from 8 to 25 and the sum of u + v is from 2 to 20.
Claim 14
Dependent Claim
108 words
A micellar formulation suitable for recovering crude oil by chemically enhanced recovery techniques which comprises: (a) 0.3 to 98 wt. % of oil; (b) 1 to 99 wt. % of water containing up to 25% dissolved inorganic salts; (c) 0.2 to 15 wt. % of at least one surfactant; (d) 0.1 to 10 wt. % of a polar polymer capable of forming a polymer-surfactant complex, said polar polymer being polyethylene oxide, polyvinyl pyrrolidone or a copolymer thereof; and (e) 0 to 15 wt. % of a co surfactant, wherein the polar polymer and surfactant form a polymer-surfactant complex characterized by a complexation energy of at least 2 Kcal/mole.
Claim 15
Dependent Claim
108 words
A micellar formulation suitable for recovering crude oil by chemically enhanced recovery techniques which comprises: (a) 0.3 to 98 wt. % of oil; (b) 1 to 99 wt. % of water containing up to 25% dissolved inorganic salts; (c) 0.2 to 15 wt. % of at least one surfactant; (d) 0.1 to 10 wt. % of a polar polymer capable of forming a polymer-surfactant complex, said polar polymer being polyethylene oxide, polyvinyl pyrrolidone or a copolymer thereof; and (e) 0 to 15 wt. % of a co surfactant, wherein the polar polymer and surfactant form a polymer-surfactant complex characterized by a complexation energy of at least 2 Kcal/mole.
Claim 16
Dependent Claim
58 words
A process for recovering crude oil from a subterranean formation which comprises injecting into the formation a stabilized microemulsion system according to any one of claims 1 to 12 and which contains a polymer-microemulsion complex in an amount effective to displace oil, driving the microemulsion system through the formation to displace oil, and recovering the resultant crude oil.
Claim 17
Dependent Claim
20 words
A process according to claim 14 wherein the microemulsion sytem is injected as a 0.01 to 1.0 pore volume slug.
Claim 18
Dependent Claim
22 words
A process according to either of claims 14 and 15 emulsion is driven through the formation with a thickened water or brine.
References Cited (Backward Citations)
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