Reversible mechanically triggered nanosilica gels

Patent metadata

Field	Value
Publication number	US-12173228-B2
Application number	US-202218066546-A
Country	US
Kind code	B2
Filing date	Dec 15, 2022
Priority date	Nov 18, 2020
Publication date	Dec 24, 2024
Grant date	Dec 24, 2024

Abstract

A reversible gel composition including nanosilica and polyethylene oxide, the nanosilica and polyethylene oxide present at concentrations operable to allow for the reversible gel composition to be a flowable liquid at pH greater than about 8 and operable to allow for the reversible gel composition to be a substantially solid gel at pH less than about 8.

First claim

That claimed is:

1. A reversible gel composition consisting of:
nanosilica, polyethylene oxide, and homopolymer poly(acrylic acid), the nanosilica and polyethylene oxide present at concentrations operable to allow for the reversible gel composition to be a flowable liquid at pH greater than about 8 and operable to allow for the reversible gel composition to be a substantially solid gel at pH less than about 8 in a hydrocarbon-bearing reservoir environment proximate a wellbore, wherein the substantially solid gel at pH less than about 8 does not return to the flowable liquid based on the properties of the hydrocarbon-bearing reservoir and wellbore over time,
where the nanosilica comprises a nanosilica colloidal liquid and polyethylene oxide between about 20,000 and about 1,000,000 viscosity average molecular weight (M v ), where the polyethylene oxide is present at between about 0.025% by weight and about 0.50% by weight of the nanosilica colloidal liquid.

2. The composition of claim 1 , where a change in the pH of the reversible gel composition or the addition of a chemical component affects the capacity of the reversible gel composition to gel in response to shear.

3. The composition according to claim 1 , where the polyethylene oxide is between about 200,000 and about 400,000 viscosity average molecular weight (M v ).

4. The composition according to claim 1 , where a pH between about 8.5 and 9 allows the reversible gel composition to gel in response to shear.

5. The composition according to claim 1 , where the homopolymer poly(acrylic acid) is present at between about 0.025% by weight and about 0.10% by weight of the reversible gel composition.

6. A reversible gel composition consisting of:
nanosilica, where the nanosilica comprises a nanosilica colloidal liquid;
polyethylene oxide, the polyethylene oxide between about 200,000 and about 400,000 viscosity average molecular weight (M v ), where the polyethylene oxide is present at between about 0.025% by weight and about 0.50% by weight of the nanosilica colloidal liquid;
an acid; and
homopolymer poly(acrylic acid);
where the nanosilica and polyethylene oxide present at concentrations operable to allow for the reversible gel composition to be a flowable liquid at pH greater than about 8 and operable to allow for the reversible gel composition to be a substantially solid gel at pH less than about 8 in a hydrocarbon-bearing reservoir environment proximate a wellbore, wherein the substantially solid gel at pH less than about 8 does not return to the flowable liquid based on the properties of the hydrocarbon-bearing reservoir and wellbore over time.

7. The composition according to claim 6 , where the acid comprises hydrochloric acid.

8. The composition according to claim 6 , where a change in the pH of the reversible gel composition or the addition of a chemical component affects the capacity of the reversible gel composition to gel in response to shear.

9. The composition according to claim 6 , where a pH between about 8.5 and 9 allows the reversible gel composition to gel in response to shear.

10. A reversible gel composition consisting of:
nanosilica, where the nanosilica comprises a nanosilica colloidal liquid;
polyethylene oxide, the polyethylene oxide between about 200,000 and about 400,000 viscosity average molecular weight (M v ), where the polyethylene oxide is present at between about 0.025% by weight and about 0.50% by weight of the nanosilica colloidal liquid;
a base; and
homopolymer poly(acrylic acid);
where the nanosilica and polyethylene oxide present at concentrations operable to allow for the reversible gel composition to be a flowable liquid at pH greater than about 8 and operable to allow for the reversible gel composition to be a substantially solid gel at pH less than about 8 in a hydrocarbon-bearing reservoir environment proximate a wellbore, wherein the substantially solid gel at pH less than about 8 does not return to the flowable liquid based on the properties of the hydrocarbon-bearing reservoir and wellbore over time.

11. The composition according to claim 10 , where the base comprises potassium hydroxide.

12. The composition according to claim 10 , where a change in the pH of the reversible gel composition or the addition of a chemical component affects the capacity of the reversible gel composition to gel in response to shear.

13. The composition according to claim 10 , where a pH between about 8.5 and 9 allows the reversible gel composition to gel in response to shear.

Assignees

• Saudi Arabian Oil Co

Inventors

• Boul Peter
• Al-Olayan Abeer Mohammad
• Rasner Diana

Classifications

• E21B21/003

  Means for stopping loss of drilling fluid (plastering the borehole wall E21B33/138) · CPC title

• C09K2208/10

  Nanoparticle-containing well treatment fluids · CPC title

• C09K8/5086

  obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• C09K8/5083

  obtained by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• C09K8/5045

  containing inorganic compounds · CPC title