Systems and methods for breaking friction reducers in-situ

Patent metadata

Field	Value
Publication number	US-10344205-B2
Application number	US-201515763411-A
Country	US
Kind code	B2
Filing date	Oct 27, 2015
Priority date	Oct 27, 2015
Publication date	Jul 9, 2019
Grant date	Jul 9, 2019

Abstract

A system and methods for breaking friction reducers in subterranean formations in-situ during hydraulic fracturing operations are disclosed. A method of fracturing a subterranean formation is disclosed, including providing a well treating fluid, adding a friction reducer into a water phase of an emulsion, adding a breaker into the water phase, and injecting the well treating fluid into the subterranean formation at a pressure sufficient to fracture the subterranean formation and invert the emulsion and double emulsion, thereby allowing the breaker to break the friction reducer. A friction reducer-breaker system for breaking a friction reducer polymer in-situ is also disclosed, including an oil phase, a water phase including friction reducer polymers and breakers in double emulsion dispersed throughout the water phase, wherein the emulsion and double emulsion are configured to invert under shear, thereby providing for mixing between the friction reducer polymers and the breakers.

First claim

We claim:

1. A method of breaking a friction reducer polymer comprising:
providing a treatment fluid comprising an aqueous base fluid and a friction reducer-breaker system, wherein the friction-reducer breaker system comprises an emulsion comprising:
(a) a first oil phase,
(b) a first water phase within the first oil phase,
(c) a second oil phase within the first water phase, and
(d) a second water phase within the second oil phase, wherein the friction reducer polymer is in the first water phase and a breaker is in the second water phase; and

pumping the treatment fluid under pressure via a pump into a wellbore to increase shear above a threshold value to invert the emulsion so that the breaker interacts with the friction reducer polymer to break the friction reducer polymer.

2. The method of claim 1 , further comprising pumping the broken friction reducer polymer out of the wellbore.

3. The method of claim 1 , wherein the friction reducer polymer comprises a polyacrylamide-based polymer.

4. The method of claim 1 , wherein the breaker comprises at least one of an instant breaker and a delayed breaker.

5. The method of claim 1 , wherein the breaker comprises at least one of an oxidizer, an acid, and an enzyme.

6. A method of fracturing a subterranean formation comprising:
providing a well treating fluid comprising water and a friction reducer-breaker system, wherein the friction-reducer breaker system comprises an emulsion comprising:
(a) a first oil phase in the water,
(b) a first water phase within the first oil phase,
(c) a second oil phase within the first water phase, and
(d) a second water phase within the second oil phase;

adding a friction reducer in the first water phase;
adding a breaker in the second water phase; and
injecting the well treating fluid into the subterranean formation at a pressure sufficient to fracture the subterranean formation and to produce a shear force above a threshold value to invert the emulsion, thereby allowing the breaker to break the friction reducer.

7. The method of claim 6 , wherein adding the friction reducer further comprises adding the friction reducer in an amount from about 0.25 to about 10 gal/1000 gal of water.

8. The method of claim 6 , wherein the breaker is added in an amount from about 0.1 to about 10 lb/1000 gal of water.

9. The method of claim 6 , wherein the friction reducer polymer comprises a polyacrylamide-based polymer.

10. The method of claim 6 , wherein the breaker comprises at least one of an instant breaker and a delayed breaker.

11. The method of claim 6 , wherein the breaker comprises at least one of an oxidizer, an acid, and an enzyme.

12. The method of claim 6 , wherein the water is fresh water.

13. The method of claim 6 , wherein the water comprises salt in a concentration of at least 0.01 gal per 1000 gallons of the water.

14. The method of claim 6 further comprising adding to the well treating fluid at least one or mixtures of a biocide, a corrosion inhibitor, a scale inhibitor, an acid, a crosslinking agent, and a surfactant.

15. A friction reducer-breaker system for breaking a friction reducer polymer in-situ in a subterranean formation including an emulsion within an aqueous phase base fluid, the emulsion comprising:
a first oil phase within the aqueous phase base fluid;
a first water phase within the first oil phase and including friction reducer polymers;
a second oil phase within the first water phase;
a second water phase within the second oil phase as a double emulsion and including breakers; and
wherein the emulsion and double emulsion are configured to invert under a threshold amount of shear, thereby providing for mixing between the friction reducer polymers and the breakers.

16. The system of claim 15 , wherein the shear is achievable by pumping the friction reducer-breaker system under pressure via a pump into a wellbore penetrating a subterranean formation.

17. The system of claim 15 , wherein the friction reducer polymers comprise a polyacrylamide-based polymer.

18. The system of claim 15 , wherein the breakers comprise at least one of an instant breaker and a delayed breaker.

19. The system of claim 15 , wherein the breakers comprise at least one of an oxidizer, an acid, and an enzyme.

20. The system of claim 15 , wherein the breakers comprise at least one of an hemicellulase enzyme, sodium persulfate, sodium perborate, ammonium persulfate, sodium chlorite, citric acid, citrate, fumaric acid, perborates, peroxides, or any mixture thereof.

Assignees

• Halliburton Energy Services Inc

Inventors

• Chung Hsinchen
• Chopade Prashant Dinkar

Classifications

• C09K2208/32

  Anticorrosion additives · CPC title

• C09K2208/28

  Friction or drag reducing additives · CPC title

• C09K2208/26

  Gel breakers other than bacteria or enzymes · CPC title

• C09K2208/24

  Bacteria or enzyme containing gel breakers · CPC title

• C09K2208/14

  Double emulsions, i.e. oil-in-water-in-oil emulsions or water-in-oil-in-water emulsions · CPC title