Well treatment

Patent metadata

Field	Value
Publication number	US-10030471-B2
Application number	US-201514790256-A
Country	US
Kind code	B2
Filing date	Jul 2, 2015
Priority date	Jul 2, 2015
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

Methods of treating a subterranean formation penetrated by a well bore, by providing a first acidic treatment fluid comprising fibers to fracture the formation and providing a non-acidic treatment fluid comprising multiple particle size acid precursors having a first average particle size between about 3 mm and 2 cm and a second amount of acid precursors having a second average size between about 1.6 and 20 times smaller than the first average particle size or a second amount of flakes having a second average size up to 10 times smaller than the first average particle size.

First claim

What is claimed is:

1. A method of treating a subterranean formation penetrated by a well bore, the method comprising:
providing a first treatment fluid comprising fibers in an acidic carrier fluid having a viscoelastic diverting acid (VDA);
pumping the first treatment fluid in the wellbore above the fracturing pressure of the formation;
providing a second treatment fluid comprising a non-acidic carrier fluid and blend including a first amount of acid precursor having a first average particle size between about 3 mm and 2 cm and a second amount of acid precursor having a second average size between about 1.6 and 20 times smaller than the first average particle size or a second amount of flakes having a second average size up to 10 times smaller than the first average particle size; and
creating a plug with the second treatment fluid.

2. The method of claim 1 , wherein the carrier fluid of the second treatment fluid is a treatment fluid selected from the group consisting of slickwater, spacer, mutual solvent, flush, fracturing fluid, scale dissolution fluid, paraffin dissolution fluid, asphaltene dissolution fluid, diverter fluid, water control agent, chelating agent, and mixtures thereof.

3. The method according to claim 1 , further comprising removing the plug.

4. The method of claim 1 , wherein the acid precursor is a polylactic acid material or a polyglycolic acid.

5. The method according to claim 1 , wherein the first treatment fluid further comprises degradable particulates.

6. The method according to claim 1 , wherein the second treatment fluid further comprises fibers.

7. The method according to claim 1 , wherein the second treatment fluid further comprises a third amount of acid precursors having a third average size smaller than the second average size.

8. The method of claim 7 , wherein the second treatment fluid further comprises a fourth and a fifth amount of acid precursors having a fourth average size smaller than the third average size, and a fifth average size smaller than the fourth average size.

9. The method according to claim 1 , wherein the second treatment fluid is such that a packed volume fraction of the blend exceeds 0.7.

10. The method of claim 1 , wherein the method further comprises subjecting the subterranean formation to a further fracturing treatment after the creating of the plug.

11. A system for wellbore treatment in a wellbore, the system comprising:
a first treatment fluid comprising fibers in an acidic carrier fluid having a viscoelastic diverting acid (VDA); and
a second treatment fluid comprising a non-acidic carrier fluid and blend including a first amount of acid precursor having a first average particle size between about 3 mm and 2 cm and a second amount of acid precursor having a second average size between about 1.6 and 20 times smaller than the first average particle size or a second amount of flakes having a second average size up to 10 times smaller than the first average particle size.

12. The system of claim 11 , wherein the carrier fluid of the second treatment fluid is a treatment fluid selected from the group consisting of slickwater, spacer, mutual solvent, flush, fracturing fluid, scale dissolution fluid, paraffin dissolution fluid, asphaltene dissolution fluid, diverter fluid, water control agent, chelating agent, and mixtures thereof.

13. The system of claim 11 , wherein the acid precursors is a polylactic acid material or a polyglycolic acid.

14. The system according to claim 11 , wherein the second treatment fluid further comprises fibers.

15. The system according to claim 11 , wherein the second treatment fluid further comprises a third amount of acid precursor having a third average size smaller than the second average size.

16. The system of claim 11 , wherein the second treatment fluid further comprises a fourth and a fifth amount of acid precursors having a fourth average size smaller than the third average size, and a fifth average size smaller than the fourth average size.

17. The system according to claim 11 , wherein the second treatment fluid is such that a packed volume fraction of the blend exceeds 0.7.

18. A method of acidizing a subterranean formation penetrated by a well bore, comprising:
providing a first treatment fluid comprising an acidic carrier fluid, solid acid precursors and fibers,
wherein the acidic carrier fluid comprises a viscoelastic diverting acid (VDA);
pumping the first treatment fluid in the wellbore above the fracturing pressure of the formation;
providing a second treatment fluid comprising a non-acidic carrier fluid, fibers, and blend including a first amount of solid acid precursor having a first average particle size between about 3 mm and 2 cm and a second amount of solid acid precursor having a second average size between about 1.6 and 20 times smaller than the first average particle size or a second amount of flakes having a second average size up to 10 times smaller than the first average particle size; and
creating a plug with the second treatment fluid.

Assignees

• Schlumberger Technology Corp

Inventors

• Lecerf Bruno
• Mayo John
• Kariampally Jacob M

Classifications

• E21B33/138 Primary

  Plastering the borehole wall; Injecting into the formation · CPC title

• C09K8/74

  combined with additives added for specific purposes · CPC title

• C09K8/52

  Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning · CPC title

• C09K2208/08

  Fiber-containing well treatment fluids · CPC title

• C09K8/76

  for preventing or reducing fluid loss · CPC title