Delivery of particulate material below ground

Patent metadata

Field	Value
Publication number	US-9234415-B2
Application number	US-86817710-A
Country	US
Kind code	B2
Filing date	Aug 25, 2010
Priority date	Aug 25, 2010
Publication date	Jan 12, 2016
Grant date	Jan 12, 2016

Abstract

A wellbore fluid comprises an aqueous carrier liquid, hydrophobic particulate material suspended therein and a gas to wet the surface of the particles and bind them together as agglomerates. The hydrophobic particulate material has a specified maximum volume median particle size d 50 of not more than 200 micron, and/or a minimum surface area of at least 30 m 2 per liter. Agglomerates of the particles contain gas and so have a bulk density lower than the density of the particles. This reduces the rate of settling. The fluid is particularly envisaged as a slickwater fracturing fluid in which the suspended particles are proppant. The small particle size and/or substantial surface area increases the amount of gas which can be retained within agglomerates and so enhances the buoyancy of the agglomerates. The end result is that a greater proportion of a hydraulic fracture is propped open.

First claim

The invention claimed is:

1. A method of delivering particulate material below ground, comprising supplying, underground, a fluid composition comprising an aqueous carrier liquid with a hydrophobic particulate material suspended therein, the hydrophobic particulate material having a volume median particle size d 50 of not more than 125 micron, determined as median diameter of spheres of equivalent volume, the fluid also comprising a gas wetting the surface of the particles and binding the particles together such that agglomerates of the particulate material held together by the gas are present below ground, wherein the agglomerates of the particulate material have a density equal to or less than 1.4 g/ml.

2. The method according to claim 1 including delivering the composition via a well bore to a subterranean location.

3. The method according to claim 2 which is a method of hydraulic fracturing, the composition being a fracturing fluid pumped under pressure down the wellbore to create a fracture in a subterranean formation and the hydrophobic particulate material being a proppant to keep open a porous flow path within the fracture.

4. The method according to claim 2 wherein the gas and the particulate materials are delivered via the wellbore in such a manner as to prevent agglomeration within the wellbore but allow agglomeration to take place at the subterranean location.

5. The method according to claim 2 wherein the gas is transported down the wellbore separately from the particulate materials so that they contact each other downhole.

6. The method according to claim 2 which is a method of fracturing a subterranean reservoir formation penetrated by a wellbore, wherein the permeability of the reservoir formation does not exceed 10 millidarcies.

7. The method according to claim 1 wherein the gas is air or nitrogen.

8. The method according to claim 1 wherein at least 90 percent of the hydrophobic particulate material has a particle size below 200 micron.

9. The method according to claim 1 wherein at least 90 percent of the hydrophobic particulate material has a particle size below 150 micron.

10. The method according to claim 1 wherein at least 90 percent of the hydrophobic particulate material has a particle size below 210 micron and at least 90 percent of the hydrophobic particulate material has a particle size above 100 micron.

11. The method according to claim 1 wherein the hydrophobic particulate material is hydrophobically modified silica, and wherein the agglomerates of the particulate material have a density equal to or less than 1.1 g/ml.

12. A method of delivering particulate material below ground, comprising supplying, underground, a fluid composition comprising an aqueous carrier liquid with a hydrophobic particulate material suspended therein, the hydrophobic particulate material having a surface area of at least 70 m 2 per liter, determined as surface area of smooth spheres of equivalent volume, the fluid also comprising a gas wetting the surface of the particles and binding the particles together such that agglomerates of the particulate material held together by the gas are present below ground, wherein the agglomerates of the particulate material have a density equal to or less than 1.4 g/ml.

13. The method according to claim 12 including delivering the composition via a well bore to a subterranean location.

14. The method according to claim 13 which is a method of hydraulic fracturing, the composition being a fracturing fluid pumped under pressure down the wellbore to create a fracture in a subterranean formation and the hydrophobic particulate material being a proppant to keep open a porous flow path within the fracture.

15. The method according to claim 13 wherein the gas and the particulate materials are delivered via the wellbore in such a manner as to prevent agglomeration within the wellbore but allow agglomeration to take place at the subterranean location.

16. The method according to claim 13 wherein the gas is transported down the wellbore separately from the particulate materials so that they contact each other downhole.

17. The method according to claim 13 which is a method of fracturing a subterranean reservoir formation penetrated by a wellbore, wherein the permeability of the reservoir formation does not exceed 10 millidarcies.

18. The method according to claim 12 wherein the hydrophobic particulate material is hydrophobically modified silica, and wherein the agglomerates of the particulate material have a density equal to or less than 1.1 g/ml.

19. A method of delivering particulate material below ground, comprising supplying, underground, a fluid composition comprising an aqueous carrier liquid with a hydrophobic particulate material suspended therein, the hydrophobic particulate material having a volume median particle size d 50 of not more than 125 micron, determined as median diameter of spheres of equivalent volume, transporting a gas down the wellbore separately from the hydrophobic particulate material, wetting the surface of the particles with the gas downhole and binding the particles together such that agglomerates of the particulate material held together by the gas are present below ground, and placing the agglomerates of the particulate material in a fracture.

20. The method according to claim 19 wherein the hydrophobic particulate material is hydrophobically modified silica, and wherein the agglomerates of the particulate material have a density equal to or less than 1.4 g/ml.

Assignees

• Hughes Trevor
• Barmatov Evgeny
• Geddes Jill
• Fuller Michael
• Drochon Bruno
• Makarychev-Mikhailov Sergey
• Schlumberger Technology Corp

Inventors

• Hughes Trevor
• Barmatov Evgeny
• Geddes Jill
• Fuller Michael
• Drochon Bruno
• Makarychev-Mikhailov Sergey

Classifications

• E21B43/267 Primary

  reinforcing fractures by propping · CPC title

• C09K8/805 Primary

  Coated proppants · CPC title

• C09K8/665

  containing inorganic compounds (proppants C09K8/80) · CPC title

• C09K2208/28

  Friction or drag reducing additives · CPC title

• C09K8/70

  characterised by their form or by the form of their components, e.g. foams · CPC title