Polyhedral oligomeric silsesquioxane as rheology booster for invert emulsion oil-based mud

Patent metadata

Field	Value
Publication number	US-12163092-B2
Application number	US-202117490294-A
Country	US
Kind code	B2
Filing date	Sep 30, 2021
Priority date	Sep 30, 2021
Publication date	Dec 10, 2024
Grant date	Dec 10, 2024

Abstract

A composition of an invert emulsion oil-based drilling fluid is provided. The composition may include an oil phase and an aqueous phase. The oil phase may include an oleaginous fluid, an organophilic clay-based solid viscosifier, and a liquid viscosifier including a POSS. Further provided is a method of introducing the composition including the POSS into a wellbore. After introduction of the composition into the wellbore, the method includes maintaining wellbore conditions to provide a stable rheological property for a period up to about 96 hours in an HPHT section of a wellbore.

First claim

What is claimed:

1. A method of introducing a drilling fluid into a wellbore, comprising:
introducing an invert emulsion oil-based drilling fluid formulation comprising an oil phase, an aqueous phase, a solid viscosifier that is an organophilic clay-based viscosifier, and a liquid viscosifier that is a polyhedral oligomeric silsesquioxane (POSS) downhole in the wellbore, and
maintaining wellbore conditions such that the invert emulsion oil-based drilling fluid formulation provides a stable rheological property including one or more of viscosity, yield point, plastic viscosity, gel strength, and electrical stability for a period up to about 96 hours,
wherein the wellbore comprises one or more high pressure, high temperature (HPHT) section including a pressure of greater than or equal to 10,000 psi, a temperature of greater than or equal to 150° C., or the pressure of greater than or equal to 10,000 psi and the temperature of greater than or equal to 150° C.

2. The method of claim 1 , where the invert emulsion oil-based drilling fluid formulation further comprises one or more selected from the group consisting of a weighting agent, a friction reducer, a filtration control agent, an emulsion activator, a primary emulsifier, and a secondary emulsifier.

3. The method of claim 2 , where the primary emulsifier comprises a fatty acid and a hydrocarbon.

4. The method of claim 2 , where the primary emulsifier is a basic emulsifier.

5. The method of claim 1 , where the viscosity relative to a shear rate is from 0.1 to 50 cP at 6 rpm.

6. The method of claim 1 , where the yield point is in a range from 1 to 100 lb/100 ft 2 .

7. The method of claim 1 , where the plastic viscosity is in a range from 20 to 150 cP.

8. The method of claim 1 , where the gel strength is in a range from 0.1 to 30 lb/100 ft 2 .

9. The method of claim 1 , where the electrical stability is in a range from 100 to 700 volts.

10. The method of claim 1 , where the POSS is a glycidyl POSS.

11. The method of claim 1 , where the oil phase includes an oleaginous fluid.

12. The method of claim 11 , where the oleaginous fluid oil includes a dearomatized mineral oil.

13. The method of claim 12 , where the dearomatized mineral oil is Safra oil.

14. The method of claim 1 , where the aqueous phase is a calcium chloride anhydride-based brine.

15. The method of claim 1 , where the solid viscosifier has a specific gravity of from 1 to 5.

16. The method of claim 1 , where the solid viscosifier includes silica in an amount of from about 1 to 20 wt % of the total weight of the solid viscosifier.

17. The method of claim 1 , where the solid viscosifier includes an amine.

18. The method of claim 17 , where the amine is a bis(hydrogenated tallow alkyl)methylamine.

19. The method of claim 17 , where a content of the amine in the solid viscosifier is a non-zero value up to about 1 wt % of the total weight of the solid viscosifier.

Assignees

• Saudi Arabian Oil Co

Inventors

• Ramasamy Jothibasu
• Wagle Vikrant

Classifications

• E21B43/12

  Methods or apparatus for controlling the flow of the obtained fluid to or in wells (E21B43/25 takes precedence; valve arrangements E21B34/00) · CPC title

• C09K2208/28

  Friction or drag reducing additives · CPC title

• E21B21/00

  Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor (freeing objects stuck in boreholes by flushing E21B31/03) · CPC title

• C09K8/36 Primary

  Water-in-oil emulsions · CPC title