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US3968840A Expired / Lapsed US ⏱️ 0.0 years remaining

Controlled rate acidization process

Assignee: Texaco Inc
•
Filing: 1973-05-25
•
Granted: 1976-07-13
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Expires: 1993-05-25
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Abstract

Abstract A process is provided whereby a subterranean formation may be treated uniformly with acid at a controlled rate to a considerable distance from an injection point. The process includes an introduction of an acid which is solid but will slowly solubilize in water or brine in a subterranean formation. The introduction of the solid acid may take place via fracture fissures in the formation and also if desired in conjunction with a propping agent.

Inventors

  • 👤 Jack F. Tate

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 21:00
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/60; C09K8/62; C09K8/72; E; E21; E21B; E21B43/00; E21B43/25; E21B43/26; E21B43/267

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 93 words
A process for increasing the productivity of a subterranean formation penetrated by a wellbore comprising forcing a fracturing fluid into the formation under sufficient pressure to fracture the formation wherein the fracturing fluid has suspended therein a solid acidic material of the formula: ##SPC3## wherein n is 1 or 2 and R is NH 2 , --Cl, --OH, --NO 2 , alkyl, carboxyl or ether which will slowly dissolve upon contact with sufficient aqueous medium and attack the formation and, displacing the fracturing fluid and suspended solid acidic material into the fractured formation.
Claim 2
Dependent Claim 93 words
A process for increasing the productivity of a subterranean formation penetrated by a wellbore comprising forcing a fracturing fluid into the formation under sufficient pressure to fracture the formation wherein the fracturing fluid has suspended therein a solid acidic material of the formula: ##SPC3## wherein n is 1 or 2 and R is NH 2 , --Cl, --OH, --NO 2 , alkyl, carboxyl or ether which will slowly dissolve upon contact with sufficient aqueous medium and attack the formation and, displacing the fracturing fluid and suspended solid acidic material into the fractured formation.
Claim 3
Dependent Claim 13 words
A process as in claim 1 wherein the fracturing fluid is an oil.
Claim 4
Dependent Claim 12 words
A process as in claim 1 wherein the fracturing fluid is aqueous.
Claim 5
Dependent Claim 22 words
A process as in claim 1 wherein the acid said solid acidic material is of the formula: ##SPC4## wherein R is --NH.
Claim 6
Dependent Claim 24 words
A process as in claim 1 wherein the solid acidic material is taken from the group consisting of sulfanilic, metanilic, orthanilic, o-salicyclic and p-hydroxybenzoic.
Claim 7
Dependent Claim 66 words
A process for increasing the productivity of a subterranean formation penetrated by a wellbore comprising forcing a fracturing fluid into the formation under sufficient pressure to fracture the formation wherein the fracturing fluid has suspended therein sulfanilic acid which will slowly dissolve upon contact with sufficient aqueous medium and attack the formation and, displacing the fracturing fluid and the suspended sulfanilic acid into the fractured formation.
Claim 8
Dependent Claim 66 words
A process for increasing the productivity of a subterranean formation penetrated by a wellbore comprising forcing a fracturing fluid into the formation under sufficient pressure to fracture the formation wherein the fracturing fluid has suspended therein sulfanilic acid which will slowly dissolve upon contact with sufficient aqueous medium and attack the formation and, displacing the fracturing fluid and the suspended sulfanilic acid into the fractured formation.

References Cited (Backward Citations)

US2766828A Cited
US2975834A Cited
US3634237A Cited
US3417817A Cited
US3441085A Cited
US3620305A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-07-13 1980-01-12 1980-07-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-07-13 1984-01-12 1984-07-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-07-13 1988-01-12 1988-07-13 $7700.00 Window Closed / Lapsed

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