US4466893A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of preparing and using and composition for acidizing subterranean formations
Assignee: Halliburton Co
•
Filing: 1982-04-19
•
Granted: 1984-08-21
•
Expires: 2002-04-19
Abstract
Abstract A composition and method of acidizing or fracturing a subterranean formation comprising contacting the formation with a composition comprising an acid, urea, and a selected gelling agent. The urea is present in an amount sufficient to extend the viscous stability of the gelled acid composition in comparison to the acid and gelling agent alone.
Inventors
- 👤 Walter R. Dill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:11
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/60; C09K8/62; C09K8/72; C09K8/74; Y; Y10; Y10S; Y10S507/00; Y10S507/922; Y10S507/923; Y10S507/933
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
113 words
A gelled acidizing composition comprising: a. an acid selected from the group consisting of hydrochloric acid, hydrofluoric acid, acetic acid and formic acid and mixtures thereof; b. a gelling agent selected from the group consisting of gum karaya, gum tragacanth, gum ghatti, gum acacia, gum konjak, shariz, locus, psyllium, tamarind, gum tara, carrageenin, gum kauri, hydroxypropyl guar, hydroxyethyl guar, carboxymethyl hydroxypropyl guar and carboxymethyl hydroxyethyl guar, said gelling agent present in an amount sufficient to gel said acid; and c. urea in an amount sufficient to extend the viscous stability of said composition in comparison to the viscous stability of a gelled acid comprising said selected acid and said selected gelling agent alone.
Claim 2
Dependent Claim
113 words
A gelled acidizing composition comprising: a. an acid selected from the group consisting of hydrochloric acid, hydrofluoric acid, acetic acid and formic acid and mixtures thereof; b. a gelling agent selected from the group consisting of gum karaya, gum tragacanth, gum ghatti, gum acacia, gum konjak, shariz, locus, psyllium, tamarind, gum tara, carrageenin, gum kauri, hydroxypropyl guar, hydroxyethyl guar, carboxymethyl hydroxypropyl guar and carboxymethyl hydroxyethyl guar, said gelling agent present in an amount sufficient to gel said acid; and c. urea in an amount sufficient to extend the viscous stability of said composition in comparison to the viscous stability of a gelled acid comprising said selected acid and said selected gelling agent alone.
Claim 3
Dependent Claim
13 words
The composition recited in claim 1 wherein said gelling agent is guar gum.
Claim 4
Dependent Claim
12 words
The composition recited in claim 2 wherein said acid is hydrochloric acid.
Claim 5
Dependent Claim
46 words
The acidizing composition as recited in claim 3 wherein said urea and said hydrochloric acid are present in said composition in an amount sufficient to produce a molar ratio of said urea to said hydrochloric acid in the range of from about 1 to about 1.
Claim 6
Dependent Claim
31 words
The acidizing composition as recited in claim 4 wherein said hydrochloric acid is present in the range of from about 10 percent to about 34 percent by weight of said composition.
Claim 7
Dependent Claim
12 words
The acidizing composition recited in claim 5 further comprising a propping agent.
Claim 8
Independent Claim
121 words
A method of preparing a gelled acid composition comprising: a. adding urea to an acid selected from the group consisting of hydrochloric, hydrofluoric, acetic, and formic to form a mixture in an amount sufficient to extend the viscous stability of said gelled acid composition in comparison to the viscous stability of a gelled acid comprising said acid and a selected gelling agent; and b. adding a gelling agent in said mixture in an amount sufficient to form said gelled acid composition, said gelling agent being selected from the group consisting of gum karaya, gum tragacanth, gum ghatti, gum acacia, gum konjak, shariz, locus, psyllium, tamarind, gum tara, carrageenin, gum kauri, hydroxypropyl guar, hydroxyethyl guar, carboxymethyl hydroxypropyl guar and carboxymethyl hydroxyethyl guar.
Claim 9
Independent Claim
121 words
A method of preparing a gelled acid composition comprising: a. adding urea to an acid selected from the group consisting of hydrochloric, hydrofluoric, acetic, and formic to form a mixture in an amount sufficient to extend the viscous stability of said gelled acid composition in comparison to the viscous stability of a gelled acid comprising said acid and a selected gelling agent; and b. adding a gelling agent in said mixture in an amount sufficient to form said gelled acid composition, said gelling agent being selected from the group consisting of gum karaya, gum tragacanth, gum ghatti, gum acacia, gum konjak, shariz, locus, psyllium, tamarind, gum tara, carrageenin, gum kauri, hydroxypropyl guar, hydroxyethyl guar, carboxymethyl hydroxypropyl guar and carboxymethyl hydroxyethyl guar.
Claim 10
Dependent Claim
13 words
The method recited in claim 7 wherein said gelling agent is guar gum.
Claim 11
Dependent Claim
12 words
The method recited in claim 8 wherein said acid is hydrochloric acid.
Claim 12
Dependent Claim
46 words
The acidizing method as recited in claim 9 wherein said urea and said hydrochloric acid are present in said composition in an amount sufficient to produce a molar ratio of said urea to said hydrochloric acid in the range of from about 1 to about 1.
Claim 13
Dependent Claim
31 words
The acidizing method as recited in claim 10 wherein said hydrochloric acid is present in the range of from about 10 percent to about 34 percent by weight of said composition.
Claim 14
Dependent Claim
20 words
The method recited in claim 7 further comprising the step of adding a propping agent to said gelled acid composition.
Claim 15
Independent Claim
135 words
A method of acid treating a subterranean formation comprising: a. contacting said formation with a gelled acid composition comprising: (i) an acid selected from the group consisting of hydrochloric acid, hydrofluoric acid, acetic acid, and formic acid and mixtures thereof; (ii) a gelling agent selected from the group consisting of gum karaya, gum tragacanth, gum ghatti, gum acacia, gum konjak, shariz, locus, psyllium, tamarind, gum tara, carrageenin, gum kauri, hydroxypropyl guar, hydroxyethyl guar, carboxymethyl hydroxypropyl guar and carboxymethyl hydroxyethyl guar, said gelling agent present in an amount sufficient to gel said acid; and (iii) urea in an amount sufficient to extend the viscous stability of said composition in comparison to the viscous stability of a gelled acid comprising said selected acid and said selected gelling agent alone; and b. withdrawing said composition from said formation.
Claim 16
Independent Claim
135 words
A method of acid treating a subterranean formation comprising: a. contacting said formation with a gelled acid composition comprising: (i) an acid selected from the group consisting of hydrochloric acid, hydrofluoric acid, acetic acid, and formic acid and mixtures thereof; (ii) a gelling agent selected from the group consisting of gum karaya, gum tragacanth, gum ghatti, gum acacia, gum konjak, shariz, locus, psyllium, tamarind, gum tara, carrageenin, gum kauri, hydroxypropyl guar, hydroxyethyl guar, carboxymethyl hydroxypropyl guar and carboxymethyl hydroxyethyl guar, said gelling agent present in an amount sufficient to gel said acid; and (iii) urea in an amount sufficient to extend the viscous stability of said composition in comparison to the viscous stability of a gelled acid comprising said selected acid and said selected gelling agent alone; and b. withdrawing said composition from said formation.
Claim 17
Dependent Claim
13 words
The method recited in claim 13 wherein said gelling agent is guar gum.
Claim 18
Dependent Claim
12 words
The method recited in claim 14 wherein said acid is hydrochloric acid.
Claim 19
Dependent Claim
46 words
The acidizing method as recited in claim 15 wherein said urea and said hydrochloric acid are present in said composition in an amount sufficient to produce a molar ratio of said urea to said hydrochloric acid in the range of from about 1 to about 1.
Claim 20
Dependent Claim
31 words
The acidizing method as recited in claim 16 wherein said hydrochloric acid is present in the range of from about 10 percent to about 34 percent by weight of said composition.
Claim 21
Dependent Claim
21 words
The method recited in claim 13 wherein said acid composition contacts said formation at a pressure sufficient to fracture said formation.
Claim 22
Dependent Claim
19 words
The method recited in claim 18 further comprising the step of incorporating a propping agent in said acid composition.
References Cited (Backward Citations)
US2596137A
Cited
US2689230A
Cited
US2778427A
Cited
US2824833A
Cited
US3233672A
Cited
US3634237A
Cited
US3826312A
Cited
US3920566A
Cited
US3824834A
Cited
CA1052557A
Cited
US4061580A
Cited
DE2901222A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-08-21 | 1988-02-20 | 1988-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-08-21 | 1992-02-20 | 1992-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-08-21 | 1996-02-20 | 1996-08-21 | $7700.00 | Window Closed / Lapsed |