CA1043091A
Expired / Lapsed
CA
⏱️ 0.0 years remaining
Well treatment composition with carbon dioxide and method
Assignee: Dow Chemical Co
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Filing: 1974-09-18
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Granted: 1978-11-28
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Expires: 1994-09-18
Abstract
Abstract A B S T R A C T Novel compositions comprising homogeneous mix-tures of liquid carbon dioxide and an anhydrous lower alkanol gelled to a viscosity of at least 10 centipoises with a hydroxypropyl methylcellulose having a methoxyl degree of substitution of form 0.2 to 1.0 and a molar substitution of hydroxypropoxyl of at least 1.2. The compositions are employed in a method of treating a sub-terranean formation penetrated by a wellbore by injecting them under pressure down the wellbore and into the forma-tion to sti,ulate production of natural gas or petroleum. Liquefied petroleum gas is normally added to the carbon dioxide, especially at higher bottom hole temperatures. Propping agents can also be mixed with these compositions prior to their injection.
Inventors
- 👤 George K. Greminger (Jr.)
- 👤 Samuel A. Pence (Jr.)
- 👤 Carl P. Strange
Bibliographic Details
Application Number
—
Jurisdiction
CA
Data Source
google_patents
Last Synchronized
2026-11-06 08:08
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/60; C09K8/62; C09K8/64; E; E21; E21B; E21B43/00; E21B43/25; E21B43/26; E21B43/2605; Y; Y10; Y10S; Y10S507/00; Y10S507/922
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
115 words
In a method for treating a subterranean formation penetrated by a wellbore which comprises injecting down the wellbore and subjecting to above-atmospheric pressure an essentially anhydrous mixture comprising liquid carbon dioxide and an anhydrous alcohol of 1 to 3 carbon atoms gelled to a viscosity of at least 10 centipoises with a cellulose ether compound, the improvement which comprises employing as gelling agent a hydroxypropyl methylcellulose having a methoxyl D.S. of from 0.2 to 1.0 and a hydroxypropoxyl M.S. of at least 1.2 and wherein the sum of said D.S. and M.S. is at least 1.8, said methylcellulose being employed in the proportion of 40 to 200 pounds per 1000 U.S. gallons of said alcohol.
Claim 2
Dependent Claim
115 words
In a method for treating a subterranean formation penetrated by a wellbore which comprises injecting down the wellbore and subjecting to above-atmospheric pressure an essentially anhydrous mixture comprising liquid carbon dioxide and an anhydrous alcohol of 1 to 3 carbon atoms gelled to a viscosity of at least 10 centipoises with a cellulose ether compound, the improvement which comprises employing as gelling agent a hydroxypropyl methylcellulose having a methoxyl D.S. of from 0.2 to 1.0 and a hydroxypropoxyl M.S. of at least 1.2 and wherein the sum of said D.S. and M.S. is at least 1.8, said methylcellulose being employed in the proportion of 40 to 200 pounds per 1000 U.S. gallons of said alcohol.
Claim 3
Dependent Claim
28 words
The method of Claim 1 wherein the amount of hydroxypropyl methylcellulose is adjusted to produce a gelled alcohol having an apparent viscosity of from 120 to 300 centipoises.
Claim 4
Dependent Claim
18 words
The method of Claim 1 wherein the hydroxypropyl methylcellulose has a hydroxypropoxyl M.S. of from 1.2 to 2.2.
Claim 5
Dependent Claim
18 words
The method of Claim 3 wherein the hydroxypropyl methylcellulose has a methoxyl D.S. of from 0.5 to 0.95.
Claim 6
Independent Claim
11 words
The method of Claim i wherein the alcohol is anhydrous methanol.
Claim 7
Dependent Claim
16 words
The method of Claim 1 wherein the liquid carbon dioxide is combined with liquid petroleum gas.
Claim 8
Dependent Claim
13 words
The method of Claim 1 wherein the gelled alcohol carries a propping agent.
Claim 9
Dependent Claim
11 words
The method of Claim 7 wherein the propping agent is sand.
Claim 10
Dependent Claim
23 words
The method of Claim 7 wherein the mixture is injected down the wellbore under a formation-fracturing pressure and such pressure is subsequently released.
Claim 11
Dependent Claim
80 words
A composition which comprises liquid carbon dioxide and an essentially anhydrous alcohol containing 1 to 3 carbon atoms and gelled to a viscosity of at least 10 centipoises with a hydroxypropyl methylcellulose have a methoxyl D.S. of from 0.2 to 1.0 and a hydropropoxyl M.S. of at least 1.2 and wherein the sum of said D.S. and M.S. is at least 1.8, said methylcellulose being employed in the proportion of 40 to 200 pounds per 1000 gallons of said alcohol.
Claim 12
Dependent Claim
80 words
A composition which comprises liquid carbon dioxide and an essentially anhydrous alcohol containing 1 to 3 carbon atoms and gelled to a viscosity of at least 10 centipoises with a hydroxypropyl methylcellulose have a methoxyl D.S. of from 0.2 to 1.0 and a hydropropoxyl M.S. of at least 1.2 and wherein the sum of said D.S. and M.S. is at least 1.8, said methylcellulose being employed in the proportion of 40 to 200 pounds per 1000 gallons of said alcohol.
Claim 13
Dependent Claim
18 words
The composition of Claim 10 wherein the hydroxypropyl methylcellulose has a hydroxypropoxyl M.S. of from 1.2 to 2.2.
Claim 14
Dependent Claim
18 words
The composition of Claim 11 wherein the hydroxypropyl methylcellulose has a methoxyl D.S. of from 0.5 to 0.95.
Claim 15
Dependent Claim
27 words
The composition of Claim 10 wherein the hydroxypropyl methylcellulose is employed in the amount of from 40 to 200 pounds per 1000 U.S. gallons of the alcohol.
Claim 16
Dependent Claim
15 words
The composition of Claim 13 which contains as a third component liquid petroleum gas (LPG).
Claim 17
Dependent Claim
35 words
A composition according to Claim 14 wherein the proportions of liquid carbon dioxide to LPG to gelled alcohol by volume range, respectively, from 3 to 1 to 1 to 1 to 9 to 5. 10
References Cited (Backward Citations)
No citation records indexed.
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