APPARATUSES, SYSTEMS, AND METHODS FOR FORMING IN-SITU GEL PILLS TO LIFT LIQUIDS FROM HORIZONTAL WELLS

• US 20130312977A1
• Filed: 04/04/2013
• Published: 11/28/2013
• Est. Priority Date: 04/04/2012
• Status: Active Grant

• Current Assignee: Clearwater International, L.L.C (Weatherford International PLC)
• Original Assignee: Weatherford/Lamb Incorporated (Weatherford International PLC)
• Inventors: Lembcke, Jeffrey John, Lane, William Charles, Smith, Clayton S.
• Granted Patent: US 9,664,009 B2
• Time in Patent Office: Days
• US Class Current: 166/311
• CPC Class Codes: E21B 37/04 operated by fluid pressure, e.g. free-piston scrapers
• CPC Class Codes: E21B 43/121 Lifting well fluids monitoring of down-hole pump systems E21B47/008

Abstract

Methods include the injection of a gelled, gelling or gellable composition into a horizontal section of a well at a location, where produced well gases or a combination of well gases and injected gases are sufficient to move the pill through the horizontal section into heal section, sweeping the horizontal section of accumulated liquids. Once in the heal section, the pill and the accumulated liquids are uplifted to the surface resulting in a cleaned well.

Claims

1. A method for cleaning horizontal section of wells comprising the steps of:

injecting a gelled, gelling or gellable composition into a horizontal section of a well at a location a distance δ

from a toe end of the well, the toe section,

forming a gelled pill at the location, and

pushing the gelled pill and accumulated liquids through the horizontal section of the well into the heal section of the well using gas pressure on a toe end side of the gelled pill.

2. The method of claim 1, further comprising the step:

uplifting the gelled pill and the accumulated liquid to the surface leaving a cleaned well.

3. The method of claim 1, further comprising the step:

breaking the gelled pill to form a broken pill, and

uplifting the broken pill and the accumulated liquid to the surface leaving a cleaned well.

4. The method of claim 1, wherein the distance δ

is sufficient for gas pressure from produced gas to push the gelled pill and accumulated liquids into the heal section of the well.

5. The method of claim 1, further comprising:

injecting gas from the surface to assist in pushing the gelled pill and accumulated liquids into the heal section of the well.

6. The method of claim 5, wherein the distance δ

is sufficient for gas pressure from produced gas to push the gelled pill and accumulated liquids into the heal section of the well.

7. The method of claim 5, wherein the injected gas may include a small amount (less than 25%) of the total gas used to push the gelled pill or pig or it may represent a major portion (greater than 50%) of the total gas.

8. The method of claim 5, wherein the distance δ

will not be dependent on produced gas and is a smaller distance than the distance δ

would have to be if no gas is injected from the surface into the well.

9. The method of claim 5, wherein the distance δ

is zero or the composition is injected at the toe of the well.

10. The method of claim 5, wherein the injected gas is selected from the group consisting of production gas, natural gas, an inert gas (membrane nitrogen, argon, etc.) or other gases that would not adversely affect the well or production tubing.

11. The method of claim 2, further comprising:

injecting gas from the surface to assist in pushing the gelled pill and accumulated liquids into the heal section of the well and to assist in lifting the gelled pill and accumulated liquids to the surface.

12. The method of claim 1, wherein the composition is an aqueous composition, anon-aqueous composition, a water-in-oil emulsion or microemulsion, and an oil-in-water emulsion or microemulsion.

13. The method of claim 12, wherein the aqueous composition includes one or a plurality of hydratable polymers.

14. The method of claim 13, wherein the hydratable polymer is selected from the group consisting of polysaccharide polymers, high-molecular weight polysaccharides composed of mannose and galactose sugars, hydropropyl guar (HPG), hydroxypropylcellulose (HPC), carboxymethyl guar (CMG), carboxymethylhydropropyl guar (CMHPG), hydroxyethylcellulose (HEC) or hydroxypropylcellulose (HPC), carboxymethylhydroxyethylcellulose (CMHEC), Xanthan, scleroglucan, polyacrylamide, polyacrylate polymers and copolymers and mixtures thereof.

17. The method of claim 1, wherein the composition includes one or a plurality of gellable and/or crosslinkable polymers.

18. The method of claim 1, wherein the compositions includes one or a plurality of gelling or crosslinking agents for gellable or crosslinkable polymers in a concentration sufficient to form a gelled composition of a desired viscosity.

15. The method of claim , wherein the composition includes one or a plurality of metal ion formate salts of the formula (HCOO⁻

)_nMⁿ⁺ and mixtures thereof, where M is a metal ion and n is the valency of the metal ion and wherein the metal ion is selected from the group consisting of an alkali metal ion, an alkaline metal ion, a transition metal ion, a lanthanide metal ion, and mixtures thereof.

16. The method of claim 15, wherein:

(1) the alkali metal ion is selected from the group consisting of Li⁺, Na⁺, K⁺, Rd⁺, Cs⁺, and mixtures thereof;

(2) the alkaline metal ion is selected from the group consisting of Mg²⁺, Ca²⁺, Sr²⁺, Ba²⁺ and mixtures thereof;

(3) the transition metal ion is selected from the group consisting of Ti⁴⁺, Zr⁴⁺, Hf⁴⁺, Zn²⁺ and mixtures thereof; and

(4) the lanthanide metal ion is selected from the group consisting of La³⁺, Ce⁴⁺, Nd³⁺, Pr²⁺, Pr³⁺, Pr⁴⁺, Sm²⁺, Sm³⁺, Gd³⁺, Dy²⁺, Dy³⁺, and mixtures thereof.

19. A system for removing accumulated liquids from horizontal portions of a well comprising:

an injection system capable of injecting a gelled, gelling or gellable composition into a horizontal portion of a well a distance δ

from a toe end of the well, the toe section,

where the distance δ

from the toe end is sufficient for produced gas to push the gelled compositions from the toe section along a horizontal section to a heal section for uplift to the surface along with any accumulated liquids in the horizontal section.

20. The system of claim 19, further comprising:

a single tube capable of injecting a gelled, gelling or gellable composition into under controlled conditions.

21. The system of claim 19, further comprising:

a plurality of tubes, where one tube is used to inject a gellable composition and one tube is used to inject a crosslinking agent or a plurality of crosslinking agents.

22. The system of claim 21, wherein the plurality of tubes further includes a tube used to inject a gas into the toe section to assist in pushing the gelled pill or pig through the horizontal section into the heal section of the well for uplift.

23. The system of claim 21, wherein the plurality of tubes further includes a tube used to inject a breaking agent into the gelled compositions.

24. The system of claim 23, wherein the breaker line may be configured to inject breaking agents as the pill or pig traverses the horizontal section or the breaker line is configured to inject the breaker only as the pill enters or approaches the heal section of the well.

25. The system of claim 19, wherein the tubing include ports that are mechanically or electrically opened to permit material to be injected anywhere along the length of the tubing.

26. The system of claim 19, wherein the tubing is permanent.

27. The system of claim 19, wherein the permanent tubing is capillary tubing.

28. The system of claim 19, wherein, if the tubing in run into and tripped out of the well, the tubing is either capillary tubing or coiled tubing.

29. The system of claim 19, wherein the composition is an aqueous composition, a non-aqueous composition, a water-in-oil emulsion or microemulsion, and an oil-in-water emulsion or microemulsion.

30. The system of claim 29, wherein the aqueous composition includes one or a plurality of hydratable polymers.

31. The system of claim 30, wherein the hydratable polymer is selected from the group consisting of polysaccharide polymers, high-molecular weight polysaccharides composed of mannose and galactose sugars, hydropropyl guar (HPG), hydroxypropylcellulose (HPC), carboxymethyl guar (CMG), carboxymethylhydropropyl guar (CMHPG), hydroxyethylcellulose (HEC) or hydroxypropylcellulose (HPC), carboxymethylhydroxyethylcellulose (CMHEC), Xanthan, scleroglucan, polyacrylamide, polyacrylate polymers and copolymers and mixtures thereof.

32. The system of claim 29, wherein the composition includes one or a plurality of metal ion formate salts of the formula (HCOO⁻

)_nMⁿ⁺ and mixtures thereof, where M is a metal ion and n is the valency of the metal ion and wherein the metal ion is selected from the group consisting of an alkali metal ion, an alkaline metal ion, a transition metal ion, a lanthanide metal ion, and mixtures thereof.

33. The system of claim 32, wherein:

(1) the alkali metal ion is selected from the group consisting of Li⁺, Na⁺, K⁺, Rd⁺, Cs⁺, and mixtures thereof;

(2) the alkaline metal ion is selected from the group consisting of Mg²⁺, Ca²⁺, Sr²⁺, Ba²⁺and mixtures thereof;

(3) the transition metal ion is selected from the group consisting of Ti⁴⁺, Zr⁴⁺, Hf⁴⁺, Zn²⁺ and mixtures thereof; and

(4) the lanthanide metal ion is selected from the group consisting of La³⁺, Ce⁴⁺, Nd³⁺, Pr²⁺, Pr³⁺, Pr⁴⁺, Sm²⁺, Sm³⁺, Gd³⁺, Dy²⁺, Dy³⁺, and mixtures thereof.

34. The system of claim 19, wherein the composition includes one or a plurality of gellable and/or crosslinkable polymers.

35. The system of claim 34, wherein the compositions includes one or a plurality of gelling or crosslinking agents for gellable or crosslinkable polymers in a concentration sufficient to form a gelled composition of a desired viscosity.