METHODS FOR TREATMENT OF A SUBTERRANEAN FORMATION

• US 20140262231A1
• Filed: 03/13/2013
• Published: 09/18/2014
• Est. Priority Date: 03/13/2013
• Status: Abandoned Application

• Current Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Original Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Inventors: Alam, MD Monsur, Fulton, Dwight, Choudhary, Yogesh Kumar
• Application Number:
  US13/799,421
• Publication Number:
  US 20140262231A1
• Time in Patent Office: Days
• US Class Current: 166/250.01
• CPC Class Codes: C09K 8/72 Eroding chemicals, e.g. acids
• CPC Class Codes: E21B 43/28 Dissolving minerals other than hydrocarbons, e.g. by an alkaline or acid leaching agent E21B43/241 takes precedence

Abstract

The present disclosure relates the methods of treating a subterranean formation. In various embodiments, an acidic treatment fluid can be injected through tubing while a non-acidic fluid is pumped through an annulus. In various embodiments, acidic treatment fluid can be pumped through coiled tubing while at least one of acidic treatment fluid and non-acidic fluid are pumped through a second tube surrounding the coiled tubing and an annulus disposed the second tube and a borehole. Various embodiments also include methods for stimulating a well and acidization of the subterranean formation.

Claims

1. A method of treating a subterranean formation, the method comprising:

injecting a treatment fluid comprising at least one of acid and solvent through a first passage while at least partially simultaneously injecting a non-acidic fluid through a second passage; and

contacting a mixture of at least the treatment fluid and the non-acidic fluid with a subterranean material downhole,

wherein the first passage comprises tubing disposed in a borehole, wherein the second passage comprises a space between the tubing and the borehole.

2. The method of claim 1, further comprising:

circulating the non-acidic fluid through the first passage toward the subterranean material downhole;

allowing the non-acidic fluid to flow up from the subterranean material downhole, prior to injecting the treatment fluid;

measuring a temperature of the circulating non-acidic fluid at a surface; and

stopping the circulation of the non-acidic fluid.

3. The method of claim 1, wherein the treatment fluid is injected through the first passage at flow rate about equal to a flow rate of the non-acidic fluid through the second passage.

4. The method of claim 1, further comprising monitoring a downhole pressure of the mixture.

5. The method of claim 4, further comprising increasing an injection rate of at least one of the treatment fluid and the non-acidic fluid when the monitored pressure is below a threshold value.

6. The method of claim 1, further comprising regulating an injection rate of at least one of the treatment fluid and the non-acidic fluid to cause a predetermined concentration of the treatment fluid in the mixture downhole.

7. The method of claim 1, wherein the treatment fluid comprises hydrochloric (HCl) acid, acetic acid, citric acid, hydrofluoric acid, formic acid, or combinations thereof.

8. The method of claim 1, wherein the treatment fluid is at least about 15% HCl.

9. The method of claim 1, wherein the non-acidic fluid comprises water, brine, diesel, solvent, base oil, emulsifiers, foaming agents, gas internal phase foams, or combinations thereof.

10. The method of claim 1, wherein the tubing comprises coiled tubing, wherein the second passage comprises a space between the coiled tubing and the borehole.

11. The method of claim 10, wherein the coiled tubing is disposed in non-coiled tubing, wherein the second passage comprises a space between the non-coiled tubing and the borehole.

12. A method of stimulating a well, the method comprising:

injecting a first non-acidic fluid through a first passage comprising tubing disposed in a borehole;

reducing the injecting of the first non-acidic fluid through the first passage;

injecting a second non-acidic fluid through a second passage comprising a space between the tubing and a borehole;

stopping the injecting of the first non-acidic fluid through the first passage, while at least partially simultaneously injecting an acidic treatment fluid through the first passage;

comingling the second non-acidic fluid of the second passage and the acidic treatment fluid of the first passage at a downhole location in the borehole;

contacting the comingled fluid with a subterranean material of the well; and

varying a concentration of the acidic treatment fluid in the comingled fluids.

13. The method of claim 12, wherein varying the concentration comprises varying a concentration of the acidic treatment fluid injected through the first passage.

14. The method of claim 12, wherein varying the concentration comprises adjusting a flow rate of at least one of the second non-acidic fluid and the acidic treatment fluid.

15. The method of claim 12, wherein the first non-acidic fluid and the second non-acidic fluid are substantially the same composition.

16. The method of claim 12, further comprising reducing a downhole temperature of at least the first passage by increasing at least one of a flow rate of the acidic treatment fluid and a flow rate of the second non-acidic fluid.

17. The method of claim 16, further comprising adjusting a flow rate of at least one of the second non-acidic fluid or the acidic treatment fluid to reduce the downhole temperature.

18. A method of acidization of a subterranean formation, the method comprising:

injecting a first non-acidic fluid through first passage comprising a tube disposed in a borehole;

reducing the injecting of the first non-acidic fluid through the tube, while at least partially simultaneously injecting a second non-acidic fluid through a second passage disposed between the tube and the borehole;

stopping the injecting of the first non-acidic fluid through the tube while at least partially simultaneously injecting acidic treatment fluid through the tube;

comingling the second non-acidic fluid and the acidic treatment fluid at a first downhole location;

contacting the comingled fluid with the subterranean formation downhole;

increasing at least one of an acidic concentration or an injection rate of the acidic treatment fluid upon detecting acidization, increased fluid leak off, or both; and

pumping at least a portion of the comingled fluids from a second downhole location to a surface.

19. The method of claim 18, wherein the tube comprises a coiled tube, wherein the second passage comprises a space between the coiled tubing and the borehole.

20. The method of claim 19, wherein the coiled tubing is disposed in a non-coiled tube, wherein the first passage comprises a space within the coiled tubing, and wherein the second passage comprises at least one of a space between the coiled tubing and the non-coiled tube and a space between the non-coiled tube and the borehole.