Fluid mixture containing compressible particles

Patent metadata

Field	Value
Publication number	US-11401459-B2
Application number	US-201916681735-A
Country	US
Kind code	B2
Filing date	Nov 12, 2019
Priority date	Nov 12, 2018
Publication date	Aug 2, 2022
Grant date	Aug 2, 2022

Abstract

A fluid mixture for attenuating pressure within a confined volume. The fluid mixture comprises an aqueous carrier fluid. The fluid mixture further comprises a plurality of compressible particles dispersed in the carrier fluid. Each of the compressible particles is fabricated to collapse in response to fluid pressure within a confined volume. Each of the compressible particles has a density that is less than a density of the carrier fluid and has a compressibility of between 10% and 30%, up to 10,000 psi. A column of fluid within a trapped annulus of a wellbore is also presented, wherein the column of fluid has a plurality of compressible particles dispersed in a carrier fluid.

First claim

What is claimed is:

1. A column of fluid within a trapped annulus of a wellbore, comprising:
an aqueous carrier fluid;
a plurality of compressible particles dispersed in the carrier fluid, the carrier fluid comprising weighting agent particles from a drilling mud, wherein each of the compressible particles is fabricated to collapse in response to fluid pressure within a confined volume; and wherein:
each of the compressible particles is buoyant when placed within the aqueous carrier fluid comprising the weighting agent particles, wherein the buoyancy of the compressible particles is achieved by providing each compressible particle with a porosity in a range between 5% and 40%, an irregular particle shape, an outer diameter in a range between 10 μm and 700 μm (in dry state), and a specific gravity in a range of plus/minus 0.5 of the specific gravity of the carrier fluid comprising the weighting agent particles, and wherein the buoyancy is provided such that the compressible particles are capable of being suspended more densely at a desired location within the confined volume;
each of the compressible particles has a compressibility of between 10% and 30%, up to 10,000 psi; and
the compressible particles are provided with a variety of irregular particle shapes, a variety of outer diameters that are in the range between 10 μm and 700 μm (in dry state), and a variety of specific gravities that are in the range of plus/minus 0.5, inclusive, of the specific gravity of the carrier fluid.

2. The column of fluid of claim 1 , wherein each of the compressible particles comprises carbon.

3. The column of fluid of claim 1 , wherein each of the compressible particles has an outer diameter that is between 40 μm and 700 μm (in dry state).

4. The column of fluid of claim 1 , wherein at least 50% of the compressible particles have a range of outer diameter that is between 50 μm and 600 μm.

5. The column of fluid of claim 1 , wherein the compressible particles have an average porosity of between 10% and 25%.

6. The column of fluid of claim 1 , wherein each of the particles has a resiliency of between 80% and 120%.

7. The column of fluid of claim 1 , wherein:
each of the compressible particles has a compressibility of between 14% and 27%, up to 10,000 psi;
an average size of each of the compressible particles is 200 μm to 400 μm (in dry state);
each of the particles has a density that is between 12.0 ppg and 12.8 ppg, inclusive; and
each of the particles has a resiliency of between 87% and 117%, inclusive.

8. The column of fluid of claim 7 , wherein:
each of the compressible particles comprises a porous graphite carbon (PGC) material wherein an inner core is composed of amorphous carbon, while an outer shell is composed of graphitic carbon; and
both the inner core and the outer shell are porous.

9. The column of fluid of claim 7 , wherein the compressible particles comprise:
first compressible particles having a first degree of compressibility; and
second compressible particles having a second degree of compressibility;
and wherein the first degree of compressibility is higher than the second degree of compressibility.

10. The column of fluid of claim 9 , wherein the first compressible particles generally reside at a location along the trapped annulus that is higher than the second compressible particles.

11. The column of fluid of claim 1 , wherein the desired location at which the compressible particles are more densely suspended comprises a central portion of the confined volume.

12. The column of fluid of claim 9 , wherein the compressible particles have a density that is less than a specific gravity of the carrier medium and wherein a majority of the first compressible particles reside in an upper one-third of a height of the fluid column.

13. The column of fluid of claim 1 , wherein the compressible particles comprise:
first compressible particles having a first density; and
second compressible particles having a second density; and
wherein the first density is greater than the second density.

14. The column of fluid of claim 13 , wherein:
the first compressible particles have a density that is less than a specific gravity of the aqueous carrier medium, and wherein a majority of the first compressible particles reside in an upper one-third of a height of the fluid column; and
the second compressible particles have a density that is greater than a specific gravity of the aqueous carrier medium, and wherein a majority of the second compressible particles reside in a lower one-third of a height of the fluid column.

15. The column of fluid of claim 1 , wherein each of the particles comprises an elastomeric coating.

16. The column of fluid of claim 1 , where each of the particles carries a negative electrical charge.

Assignees

• Exxonmobil Upstream Res Co

Inventors

• Narhi Ward E
• Kibey Sandeep A

Classifications

• E21B43/08

  Screens or liners {(expandable screens or liners E21B43/108)} · CPC title

• C09K8/805 Primary

  Coated proppants · CPC title

• E21B41/00

  Equipment or details not covered by groups E21B15/00 - E21B40/00 · CPC title

• C09K8/03 Primary

  Specific additives for general use in well-drilling compositions · CPC title