Drilling fluids and methods of use

Patent metadata

Field	Value
Publication number	US-11124686-B2
Application number	US-201615177808-A
Country	US
Kind code	B2
Filing date	Jun 9, 2016
Priority date	Jun 11, 2015
Publication date	Sep 21, 2021
Grant date	Sep 21, 2021

Abstract

Drilling fluid compositions and methods of using them are described. The drilling fluid compositions comprise nanocomposites comprising core-shell morphology, wherein the core material comprises a nanoparticle having an average particle size of about 5 nm to 100 nm, and the shell material comprises a crosslinked polymer comprising acrylamide repeat units. The nanocomposites are effective fluid loss control agents when the drilling fluids are employed in mud drilling operations.

First claim

We claim:

1. A drilling fluid comprising:
a water source;
a bridging agent; and
a fluid loss additive comprising a nanocomposite, the nanocomposite comprising a core-shell wherein the core-shell comprises a core and a shell, wherein the core comprises an inorganic nanoparticle having an average particle size of about 5 nm to 500 nm and wherein the inorganic nanoparticle is selected from silica, treated or partially treated fumed silica, colloidal silica, or silica-alumina composite particles, or titania and the shell comprises a crosslinked polymer comprising acrylamide repeat units, acrylic acid repeat units or a salt thereof, 2-acryloylamino-2-methylpropane-1-sulfonic acid repeat units or a salt thereof, or a combination thereof, wherein the crosslinking polymer is from about 0.1 wt % to 1 wt %,
wherein fluid loss of the drilling fluid is less than the fluid loss with only the shell.

2. The drilling fluid of claim 1 wherein the bridging agent is calcium carbonate.

3. The drilling fluid of claim 1 wherein the nanoparticle comprises silica or titania.

4. The drilling fluid of claim 3 wherein the nanoparticle is hydrophobically modified.

5. The drilling fluid of claim 1 wherein the crosslinked polymer comprises an N,N′-methylenebisacrylamide crosslinker.

6. The drilling fluid of claim 1 wherein the weight ratio of nanoparticle to polymer is about 1:100 to 50:50.

7. The drilling fluid of claim 1 wherein the nanocomposite is present at about 0.5 wt % to 5 wt % of the fluid weight.

8. The drilling fluid of claim 1 wherein the nanocomposite comprises two or more nanocomposite sources.

9. The drilling fluid of claim 1 wherein the nanocomposite comprises two or more nanoparticle sources.

10. The drilling fluid of claim 1 wherein the nanocomposite is thermally stable up to 250° C.

11. The drilling fluid of claim 1 wherein the nanocomposite does not gel.

12. The drilling fluid of claim 1 wherein the fluid loss of the drilling fluid is less than about 10 mL at 149° C.

13. The drilling fluid of claim 1 wherein the nanocomposite is in a water in oil latex form.

Assignees

• Championx Usa Inc

Inventors

• Rojas Mario Roberto
• Balsamo De Hernandez Vittoria

Classifications

• C09K2208/18

  Bridging agents, i.e. particles for temporarily filling the pores of a formation; Graded salts · CPC title

• C09K8/467

  containing additives for specific purposes · CPC title

• C04B28/00

  Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements · CPC title

• C09K2208/10

  Nanoparticle-containing well treatment fluids · CPC title

• C09K8/487

  Fluid loss control additives; Additives for reducing or preventing circulation loss · CPC title