Nano-dispersion well servicing fluid containing a pH adjuster

Patent metadata

Field	Value
Publication number	US-9518213-B2
Application number	US-201514795504-A
Country	US
Kind code	B2
Filing date	Jul 9, 2015
Priority date	May 28, 2010
Publication date	Dec 13, 2016
Grant date	Dec 13, 2016

Abstract

A nano-dispersion well servicing fluid is disclosed. The well servicing fluid is formulated with components comprising: nanoparticles comprising at least one material chosen from aluminum oxides, aluminum hydroxides, aluminum hydroxyoxides, zirconium oxides, zirconium hydroxides, zirconium hydroxyoxides, wherein the concentration of nanoparticles is greater than 0.5% by weight based on the total weight of the nano-dispersion well servicing fluid. The well servicing fluid also comprises an aqueous base continuous phase. Methods of employing the nano-dispersion to service a wellbore are also disclosed.

First claim

What is claimed is:

1. A nano-dispersion well servicing fluid in a wellbore, the fluid being formulated with components comprising:
nanoparticles comprising at least one material chosen from aluminum oxides, aluminum hydroxides, aluminum hydroxyoxides, zirconium oxides, zirconium hydroxides, zirconium hydroxyoxides, the concentration of nanoparticles being greater than 0.5% by weight based on the total weight of the nano-dispersion well servicing fluid;
an aqueous base continuous phase, the nanoparticles forming a dispersion in the aqueous base continuous phase, the nanoparticles having a crystallized size of 100 nm or less in diameter prior to being dispersed, and the nanoparticles carrying a charge resulting in a Zeta potential in the nano-dispersion well servicing fluid; and
a pH adjuster configured to decrease the Zeta potential of the nano-dispersion well servicing fluid in the wellbore closer to zero and thereby to increase viscosity, the nano-dispersion well servicing fluid exhibiting a viscosity greater than would be exhibited without the pH adjuster.

2. The fluid of claim 1 , wherein the concentration of nanoparticles ranges from about 2% to about 20% by weight based on the total weight of the nano-dispersion well servicing fluid.

3. The fluid of claim 1 , wherein the fluid does not comprise a viscoelastic surfactant gelling agent in an amount effective to significantly increase the viscosity of the fluid.

4. The fluid of claim 1 , wherein the nanoparticles comprise more than 50 wt. % boehmite.

5. The fluid of claim 1 , wherein the pH adjuster decreases Zeta potential by increasing pH.

6. The fluid of claim 1 , having a Zeta potential ranging from about 0 to about 50.

7. The fluid of claim 1 , having a pH ranging from about 2 to about 14.

8. The fluid of claim 1 , further comprising at least one delayed compound chosen from pH adjusters, surfactants, and esters configured to increase Zeta potential after a delay and thereby to decrease viscosity.

9. The fluid of claim 1 , wherein the pH adjuster is chosen from NaOH, KOH, Ca(OH) 2 , sodium bicarbonate, potassium carbonate, and sodium carbonate.

10. The fluid of claim 8 , wherein the at least one delayed compound is an ester of polycarboxylic acid.

11. The fluid of claim 1 , further comprising proppant or gravel.

12. The fluid of claim 1 , wherein the continuous phase is a liquid chosen from fresh water, brine, and produced water.

13. The fluid of claim 12 , wherein the concentration of salt in the brine is 0.5% by weight or more, based on the total weight of the brine.

14. The fluid of claim 1 , wherein the fluid is formulated with at least one breaker.

15. The fluid of claim 1 , wherein the fluid is formulated with at least one additional compound chosen from water wetting surfactants, non-emulsifiers, additional viscosifying agents, surfactants, clay stabilization additives, scale dissolvers, biopolymer degradation additives, fluid loss control additives and high temperature stabilizers.

16. A nano-dispersion well servicing fluid in a wellbore, the fluid being formulated with components comprising:
nanoparticles comprising at least one material chosen from aluminum oxides, aluminum hydroxides, aluminum hydroxyoxides, zirconium oxides, zirconium hydroxides, zirconium hydroxyoxides, the concentration of nanoparticles being greater than 0.5% by weight based on the total weight of the nano-dispersion well servicing fluid;
an aqueous base continuous phase, the nanoparticles forming a dispersion in the aqueous base continuous phase, the nanoparticles having a crystallized size of 100 nm or less in diameter prior to being dispersed, and the nanoparticles carrying a charge resulting in a Zeta potential ranging from about 0 to about 50 in the nano-dispersion well servicing fluid; and
a pH adjuster configured to decrease the Zeta potential of the nano-dispersion well servicing fluid in the wellbore closer to zero by increasing pH and thereby to increase viscosity, the nano-dispersion well servicing fluid exhibiting a viscosity greater than would be exhibited without the pH adjuster; and
an ester configured to increase Zeta potential after a delay and thereby to decrease viscosity.

17. The fluid of claim 16 , wherein the pH adjuster is chosen from NaOH, KOH, Ca(OH) 2 , sodium bicarbonate, potassium carbonate, and sodium carbonate and the at least one delayed compound is an ester of polycarboxylic acid.

18. The fluid of claim 17 , further comprising proppant or gravel.

Assignees

• Baker Hughes Inc

Inventors

• Gupta D V Satyanarayana
• Cawiezel Kay Elaine

Classifications

• C09K8/665 Primary

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

• C09K2208/10

  Nanoparticle-containing well treatment fluids · CPC title

• C09K8/845

  containing inorganic compounds · CPC title

• C09K8/80

  Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open · CPC title

• C09K8/685

  containing cross-linking agents · CPC title