Polymer-based drilling fluids containing non-biodegradable materials and methods for use thereof

Patent metadata

Field	Value
Publication number	US-10233374-B2
Application number	US-201415311993-A
Country	US
Kind code	B2
Filing date	Aug 5, 2014
Priority date	Aug 5, 2014
Publication date	Mar 19, 2019
Grant date	Mar 19, 2019

Abstract

Polymer-based drilling fluids may be used as an alternative to drilling fluids containing bentonite or other clay materials, although filter cake formation with polymer-based drilling fluids can often be inadequate. Drilling methods can comprise: providing a drilling fluid comprising a carrier fluid, a non-crosslinked hydroxyalkylcellulose polymer, and a plurality of non-biodegradable particulates; drilling a borehole in the presence of the drilling fluid; and forming a filter cake within the borehole, the filter cake comprising the non-crosslinked hydroxyalkylcellulose polymer and the non-biodegradable particulates.

First claim

The invention claimed is:

1. A drilling method comprising:
providing a drilling fluid comprising a carrier fluid, a non-crosslinked hydroxyethylcellulose polymer, and a plurality of silica particulates;
drilling a borehole in the presence of the drilling fluid; and
forming a filter cake within the borehole, the filter cake comprising the non-crosslinked hydroxyethylcellulose polymer and the silica particulates,
wherein the silica particulates have a particle size greater than 1 micron and less than 20 microns,
wherein a mass ratio of the non-crosslinked hydroxyethylcellulose polymer to the silica particulates is within a range from 0.5:1 to about 1.5:1.

2. The drilling method of claim 1 , wherein the drilling fluid is substantially free of bentonite.

3. The drilling method of claim 1 , wherein the borehole defines a water well or is within a mineral deposit.

4. The drilling method of claim 1 , wherein the drilling fluid further comprises a viscosity-enhancing polymer.

5. The drilling method of claim 4 , wherein the viscosity-enhancing polymer comprises a partially hydrolyzed polyacrylamide.

6. The drilling method of claim 4 , wherein a viscosity of the drilling fluid ranges between about 5 cP and about 35 cP.

7. A drilling fluid comprising:
a carrier fluid;
a non-crosslinked hydroxyethylcellulose polymer; and
a plurality of silica particulates,
wherein the non-biodegradable silica particulates have a particle size greater than 1 micron and less than 20 microns,
wherein a mass ratio of the non-crosslinked hydroxyethylcellulose polymer to the silica particulates is within a range from 0.5:1 to about 1.5:1.

8. The drilling fluid of claim 7 , further comprising:
a viscosity-enhancing polymer.

9. The drilling fluid of claim 8 , wherein the viscosity-enhancing polymer comprises a partially hydrolyzed polyacrylamide.

Assignees

• Halliburton Energy Services Inc

Inventors

• May Preston Andrew
• Collins Ryan Patrick

Classifications

• C09K8/516

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

• C09K8/03

  Specific additives for general use in well-drilling compositions · CPC title

• C09K8/514

  of natural origin, e.g. polysaccharides, cellulose (C09K8/512 takes precedence) · CPC title

• C09K8/12

  containing synthetic organic macromolecular compounds or their precursors · CPC title

• E21B33/138

  Plastering the borehole wall; Injecting into the formation · CPC title