HYBRID SWELL PACKER FOR HIGH TEMPERATURE OIL/GAS APPLICATIONS

Abstract

A work string includes a mandrel and a swellable packer disposed on the mandrel. The swellable packer includes an elastomer material, a first set of first particles disposed within the elastomer material, wherein the first particles are composed of a water-swell compound configured to swell when placed in contact with water, and a second set of second particles disposed within the elastomer material, wherein the second particles are composed of an oil-swell compound configured to swell when placed in contact with oil.

Description

BACKGROUND

In the resource recovery industry and fluid sequestration industry, swellable packers are used to provide a seal in a borehole in order to isolate hydrocarbon subsurface formation. A swellable packer expands radially when it comes into contact with a swelling medium such as oil or water. Any swellable packer is susceptible to de-swelling if the swelling medium (e.g., oil, water) is no longer present. For example, a presence of a gas can cause the swelling medium to exit the swellable packer, causing the swellable packer to decrease in volume, thereby weakening or destroying the seal. Therefore, there is a need for a swellable packer that can maintain its seal in the borehole in the presence of a gas in the borehole.

SUMMARY

Disclosed herein is a swellable packer. The swellable packer includes an elastomer material, a first set of first particles disposed within the elastomer material, wherein the first particles are composed of a water-swell compound configured to swell when placed in contact with water, and a second set of second particles disposed within the elastomer material, wherein the second particles are composed of an oil-swell compound configured to swell when placed in contact with oil.

Also disclosed herein is a work string for use in a borehole. The work string includes a mandrel and a swellable packer disposed on the mandrel. The swellable packer includes an elastomer material, a first set of first particles disposed within the elastomer material, wherein the first particles are composed of a water-swell compound configured to swell when placed in contact with water, and a second set of second particles disposed within the elastomer material, wherein the second particles are composed of an oil-swell compound configured to swell when placed in contact with oil.

BRIEF DESCRIPTION OF THE DRAWINGS

The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:

FIG. 1 shows and illustrative borehole system in an exemplary embodiment;

FIG. 2 illustrates a section of the work string with a hybrid packer in a non-deployed state;

FIG. 3 illustrates the section of the work string with a hybrid packer in a deployed state; and

FIG. 4 shows a packer material of the swellable packer, in an illustrative embodiment.

DETAILED DESCRIPTION

A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.

Referring to FIG. 1, a borehole system 100 is illustrated. The borehole system 100 includes a borehole 102 in a subsurface formation 104. A work string 106 extends into the borchole 102 from a platform 108 at the earth's surface. The work string 106 is shown as a production string in FIG. 1, can be a drill string, sequestration string, etc., in alternative embodiments. A packer 110 is disposed on the work string 106 and is lowered into the borehole 102 along with the work string 106. The packer 110 can be a swellable packer that can swell when it comes into contact with a swelling medium, such as a water-based fluid or an oil-based fluid. Upon swelling, the packer 110 contacts an inner wall 112 of the borehole 102 to create a seal. The work string 106 can include a plurality of packers 110 axially spaced from each other. The packers 110 are spaced so as to isolate production zones (Z1, Z2) once deployed, allowing a production fluid 114 to flow from the production zones into an interior bore 116 of the work string 106. The production fluid 114 flows uphole through the interior bore 116 toa surface location, such as a storage tank 118, for example. The production fluid can include a water-based fluid, oil-based fluid and/or gas condensates.

FIG. 2 illustrates a section 200 of the work string 106 with a hybrid packer in a non-deployed state. The hybrid packer 202 is supported by a mandrel 204 of the work string 106. The hybrid packer 202 is swellable packer that includes a selectively deployed sealing element including a swellable elastomer. The hybrid packer 202 has a first volume when in the non-deployed state. The radial extent of the hybrid packer 202 when in the non-deployed state is such that the work string 106 can be run into the borehole 102.

FIG. 3 illustrates the section 200 of the work string 106 with a hybrid packer 202 in a deployed state. When the hybrid packer 202 contacts a water-based fluid or an oil-based fluid, the hybrid packer 202 expands or swells to a second volume. The second volume is greater than the first volume shown in FIG. 2. In the second volume, the shape of the hybrid packer 202 conforms to the inner wall 112 of the borehole 102.

FIG. 4 shows a swellable material 400 of the hybrid packer 202, in an illustrative embodiment. The swellable material 400 includes an elastomer material 402. The elastomer material 402 can be rubber, for example. The rubber can be resistant to acids, such as hydrochloric acid (HCl) and hydrogen sulfide (H₂S). In an embodiment, the elastomer material 402 is ethylene propylene diene monomer (EPDM). A first set of first particles (i.e., water-swell particles 404) and a second set of second particles (i.e., oil-swell particles 406) are dispersed within the elastomer material 402. The water-swell particles are made of a water-swell material that swells when in contact with water or a water-based fluid. The oil-swell particles are made of an oil-swell compound that swells when in contact with oil or an oil-based fluid. The oil-swell compound and/or the water-swell compound can be a super-absorbent polymer (SAP). Some examples of SAPs include sodium polyacrylate, potassium polyacrylate, etc.

Each of the water-swell particles 404 and oil-swell particles 406 are present in non-zero quantities in the elastomer material 402. Due to its composition, the hybrid packer 202 can absorb both water-based fluids and oil-based fluids and can maintain its sealing capabilities (i.e., does not dehydrate) in the presence of gas condensates. In various embodiments, the ratio of water-swell particles 404 to oil-swell particles 406 is 1:1 (50 % water-swell particles, 50% oil-swell particles). In other embodiments, the ratio is anywhere between 3:7 to 7:3 (such as 30% to 70%, 40% to 60%, 60% to 40% and 70% to 30%). An amount of oil-based fluid and water-based fluid in the borehole 102 can be determined the an appropriate swellable packer. The selected hybrid pack can have a ratio or percentage of water-swell particles 404 and oil-swell particles 406 that matches or substantially matches a ratio of the water-based fluid to oil-based fluid in the borehole 102.

The water-swell particles 404 and oil-swell particles 406 can be interspersed in the elastomer material 402 to allow transfer of fluids from one like swell particle to another, to enable uniform swelling of the hybrid elastomer. The water-swell particles 404 and the oil-swell particles 406 can be evenly distributed throughout the elastomer material 402. In other embodiments, the water-swell particles 404 and the oil-swell particles 406 can be distributed with a radially dependent density.

Set forth below are some embodiments of the foregoing disclosure:

• • Embodiment 1. A swellable packer including an elastomer material, a first set of first particles disposed within the elastomer material, wherein the first particles are composed of a water-swell compound configured to swell when placed in contact with water, and a second set of second particles disposed within the elastomer material, wherein the second particles are composed of an oil-swell compound configured to swell when placed in contact with oil.
  • Embodiment 2. The swellable packer of any prior embodiment, wherein at least one of the water-swell compound and the oil-swell compound is a super-absorbent polymer (SAP).
  • Embodiment 3. The swellable packer of any prior embodiment, wherein the SAP is at least one of: (i) sodium polyacrylate; and (ii) potassium polyacrylate.
  • Embodiment 4. The swellable packer of any prior embodiment, wherein a percentage of first particles to second particles is selected based on a ratio of water-based fluid to oil-based fluid in a borehole, respectively.
  • Embodiment 5. The swellable packer of any prior embodiment, wherein the percentage of first particles to second particles is one of: (i) 70%/30%; (ii) 60%/40%; (iii) 50%/50% (iv) 40%/60%; and (v) 30%/70%.
  • Embodiment 6. The swellable packer of any prior embodiment, wherein the swellable packer is disposed on a mandrel of a work string.
  • Embodiment 7. The swellable packer of any prior embodiment, wherein the work string is one of: (i) a drill string; (ii) a production string; and (iii) a sequestration string.
  • Embodiment 8. The swellable packer of any prior embodiment, wherein the oil-swell particles and the water-swell particles are one of: (i) evenly distributed throughout the elastomer material; and (ii) distributed through the elastomer material with a radially dependent density.
  • Embodiment 9. A work string for use in a borehole, including a mandrel and a swellable packer disposed on the mandrel. The swellable packer includes an elastomer material, a first set of first particles disposed within the elastomer material, wherein the first particles are composed of a water-swell compound configured to swell when placed in contact with water, and a second set of second particles disposed within the elastomer material, wherein the second particles are composed of an oil-swell compound configured to swell when placed in contact with oil.
  • Embodiment 10. The work string of any prior embodiment, wherein at least one of the water-swell compound and the oil-swell compound is a super-absorbent polymer (SAP).
  • Embodiment 11. The work string of any prior embodiment, wherein the SAP is at least one of: (i) sodium polyacrylate; and (ii) potassium polyacrylate.
  • Embodiment 12. The work string of any prior embodiment, wherein a percentage of first particles to second particles is selected based on a ratio of water-based fluid to oil-based fluid, respectively.
  • Embodiment 13. The work string of any prior embodiment, wherein the percentage of first particles to second particles is one of: (i) 70%/30%; (ii) 60%/40%; (iii) 50%/50% (iv) 40%/60%; and (v) 30%/70%.
  • Embodiment 14. The work string of any prior embodiment, wherein the work string is one of: (i) a drill string; (ii) a production string; and (iii) a sequestration string.
  • Embodiment 15. The work string of any prior embodiment, wherein the oil-swell particles and the water-swell particles are one of: (i) evenly distributed throughout the elastomer material; and (ii) distributed through the elastomer material with a radially dependent density.

The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Further, it should be noted that the terms “first,” “second,” and the like herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The terms “about”, “substantially” and “generally” are intended to include the degree of error associated with measurement of the particular quantity based upon the equipment available at the time of filing the application. For example, “about” and/or “substantially” and/or “generally” can include a range of ±8% a given value.

The teachings of the present disclosure may be used in a variety of well operations. These operations may involve using one or more treatment agents to treat a formation, the fluids resident in a formation, a borehole, and/or equipment in the borehole, such as production tubing. The treatment agents may be in the form of liquids, gases, solids, semi-solids, and mixtures thereof. Illustrative treatment agents include, but are not limited to, fracturing fluids, acids, steam, water, brine, anti-corrosion agents, cement, permeability modifiers, drilling muds, emulsifiers, demulsifiers, tracers, flow improvers etc. Illustrative well operations include, but are not limited to, hydraulic fracturing, stimulation, tracer injection, cleaning, acidizing, steam injection, water flooding, cementing, etc.

While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited.

Claims

1. A swellable packer, comprising:

an elastomer material;

a first set of first particles disposed within the elastomer material, wherein the first particles are composed of a first compound that is a water-swell compound configured to swell when placed in contact with water; and

a second set of second particles disposed within the elastomer material, wherein the second particles are composed of a second compound, diferent than the first compound that is an oil-swell compound configured to swell when placed in contact with oil.

2. The swellable packer of claim 1, wherein at least one of the water-swell compound and the oil-swell compound is a super-absorbent polymer (SAP).

3. The swellable packer of claim 2, wherein the SAP is at least one of: (i) sodium polyacrylate; and (ii) potassium polyacrylate.

4. The swellable packer of claim 1, wherein a percentage of first particles to second particles is selected based on a ratio of water-based fluid to oil-based fluid in a borehole, respectively.

5. The swellable packer of claim 1, wherein the percentage of first particles to second particles is one of: (i) 70%/30%; (ii) 60%/40%; (iii) 50%/50% (iv) 40%/60%; and (v) 30%/70%.

6. The swellable packer of claim 1, wherein the swellable packer is disposed on a mandrel of a work string.

7. The swellable packer of claim 6, wherein the work string is one of: (i) a drill string; (ii) a production string; and (iii) a sequestration string.

8. The swellable packer of claim 1, wherein the oil-swell particles and the water-swell particles are one of: (i) evenly distributed throughout the elastomer material; and (ii) distributed through the elastomer material with a radially dependent density.

9. A work string for use in a borehole, comprising:

a mandrel;

a swellable packer disposed on the mandrel, the swellable packer including: an elastomer material; a first set of first particles disposed within the elastomer material, wherein the first particles are composed of a first compound that is a water-swell compound configured to swell when placed in contact with water; and a second set of second particles disposed within the elastomer material, wherein the second particles are composed of a second compound, different than the first compound, that is an oil-swell compound configured to swell when placed in contact with oil.

10. The work string of claim 9, wherein at least one of the water-swell compound and the oil-swell compound is a super-absorbent polymer (SAP).

11. The work string of claim 10, wherein the SAP is at least one of: (i) sodium polyacrylate; and (ii) potassium polyacrylate.

12. The work string of claim 9, wherein a percentage of first particles to second particles is selected based on a ratio of water-based fluid to oil-based fluid, respectively.

13. The work string of claim 9, wherein the percentage of first particles to second particles is one of: (i) 70%/30%; (ii) 60%/40%; (iii) 50%/50% (iv) 40%/60%; and (v) 30%/70%.

14. The work string of claim 9, wherein the work string is one of: (i) a drill string; (ii) a production string; and (iii) a sequestration string.

15. The work string of claim 9, wherein the oil-swell particles and the water-swell particles are one of: (i) evenly distributed throughout the elastomer material; and (ii) distributed through the elastomer material with a radially dependent density.