US4701270A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Novel compositions suitable for treating deep wells
Assignee: Canadian Fracmaster Ltd
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Filing: 1986-02-18
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Granted: 1987-10-20
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Expires: 2006-02-18
Abstract
Abstract A viscosity-increased liquid carbon dioxide fracturing fluid is provided for the treatment of subterranean gas-bearing formations. The composition comprises liquid carbon dioxide which has been thickened by the addition of a small amount of a copolymer which is the reaction product of liquid carbon dioxide and an alkene oxide, preferably propylene oxide. The use of the copolymer thickener provides a CO 2 fracturing fluid which may be pumped at a high rate, will not readily boil or foam, will carry a propping agent and will completely degrade within the formation.
Inventors
- 👤 Ronald S. Bullen
- 👤 Joseph Mzik
- 👤 Jean P. Richard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:29
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/60; C09K8/62; Y; Y10; Y10S; Y10S507/00; Y10S507/922
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
57 words
An anhydrous deep well fracturing composition which comprises liquid carbon dioxide thickened with from 1.5% to 3.5% by weight of the total composition of the reaction product of an alkene oxide of 2-4 carbon atoms and liquid carbon dioxide the said reaction product being a viscosity-increasing liquid copolymer having a molecular weight of from 20,000 to 150,000.
Claim 2
Dependent Claim
57 words
An anhydrous deep well fracturing composition which comprises liquid carbon dioxide thickened with from 1.5% to 3.5% by weight of the total composition of the reaction product of an alkene oxide of 2-4 carbon atoms and liquid carbon dioxide the said reaction product being a viscosity-increasing liquid copolymer having a molecular weight of from 20,000 to 150,000.
Claim 3
Dependent Claim
47 words
A process for preparing a fracturing composition as claimed in claim 1 comprising reacting liquid carbon dioxide with an alkene oxide of 2-4 carbon atoms in the presence of a catalyst selected from the group consisting of diethylzinc and acetic acid anhydride dissolved in a carried liquid.
Claim 4
Dependent Claim
25 words
A process as claimed in claim 2 wherein the reacting mixture also contains a co-catalyst selected from one or more multi-valent salt of acetic acid.
Claim 5
Dependent Claim
17 words
A process as claimed in claim 3 where the weight ratio of catalyst to co-catalyst is 33:1.
Claim 6
Dependent Claim
22 words
A process as claimed in claim 2 wherein the carrier liquid is selected from the group consisting of benzene, 1,4-dioxane and hexane.
Claim 7
Dependent Claim
63 words
A fluid fracturing composition for a subterranean formation which composition comprises from 96.5% to 98.5% by weight of liquid carbon dioxide thickened with from 1.5% to 3.5% by weight of the reaction product of an alkene oxide of 2-4 carbon atoms and liquid carbon dioxide the said reaction product being a viscosity-increasing liquid copolymer having a molecular weight of from 20,000 to 150,000.
Claim 8
Dependent Claim
63 words
A fluid fracturing composition for a subterranean formation which composition comprises from 96.5% to 98.5% by weight of liquid carbon dioxide thickened with from 1.5% to 3.5% by weight of the reaction product of an alkene oxide of 2-4 carbon atoms and liquid carbon dioxide the said reaction product being a viscosity-increasing liquid copolymer having a molecular weight of from 20,000 to 150,000.
Claim 9
Dependent Claim
12 words
A fracturing composition as claimed in claim 6 also containing a proppant.
References Cited (Backward Citations)
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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) | 1990-10-19 | 1991-04-20 | 1991-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-10-19 | 1995-04-20 | 1995-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-10-19 | 1999-04-20 | 1999-10-20 | $7700.00 | Window Closed / Lapsed |