Drilling fluid composition containing treated date pit particles and methods of use thereof

Patent metadata

Field	Value
Publication number	US-10442972-B2
Application number	US-201815882318-A
Country	US
Kind code	B2
Filing date	Jan 29, 2018
Priority date	Jan 29, 2018
Publication date	Oct 15, 2019
Grant date	Oct 15, 2019

Abstract

A drilling fluid composition including a viscosifier, treated date pit particles which are i) de-oiled and ii) treated with a base or both a base and an acid, and an aqueous base fluid, wherein the treated date pit particles are present in an amount of 0.01-5 wt %, relative to a total weight of the drilling fluid composition. A method of making the drilling fluid composition by de-oiling date pit particles, treating with a base or a base and an acid in a freeze/thaw process, and adding the freeze/thaw mixture to the viscosifier and the aqueous base fluid. A process for drilling a subterranean geological formation with the drilling fluid composition.

First claim

The invention claimed is:

1. A drilling fluid composition, comprising:
a viscosifier;
treated date pit particles, which are
i) de-oiled and
ii) treated with a base or both a base and an acid; and

an aqueous base fluid;
wherein the treated date pit particles are present in an amount of 0.01-5 wt %, relative to a total weight of the drilling fluid composition.

2. The drilling fluid composition of claim 1 , wherein the viscosifier is bentonite.

3. The drilling fluid composition of claim 1 , wherein the viscosifier is present in an amount of 1-10 wt %, relative to a total weight of the drilling fluid composition.

4. The drilling fluid composition of claim 1 , wherein the treated date pit particles are ii) treated with a base.

5. The drilling fluid composition of claim 4 , wherein the base is sodium hydroxide.

6. The drilling fluid composition of claim 4 , which has a filtration water loss volume of 15-28 mL after 30 min under a pressure of 100 psi.

7. The drilling fluid composition of claim 1 , wherein the treated date pit particles are ii) treated with both a base and an acid.

8. The drilling fluid composition of claim 7 , wherein the base is sodium hydroxide and the acid is acetic acid or sulfuric acid.

9. The drilling fluid composition of claim 7 , which has a filtration water loss volume of 30-40 mL after 30 min under a pressure of 100 psi.

10. The drilling fluid composition of claim 1 , which has a density of 6.5-8.5 lb/gal.

11. The drilling fluid composition of claim 1 , which has a plastic viscosity of 3.0-3.5 cP.

12. The drilling fluid composition of claim 1 , further comprising at least one additive selected from the group consisting of an antiscalant, a thickener, a deflocculant, a lubricant, a buffer, a biocide, and a weighting agent.

13. The drilling fluid composition of claim 1 , which is substantially free of a fluid loss additive, a density reducing agent, and a rheology modifying agent, other than the treated date pit particles and the viscosifier.

14. A method of making the drilling fluid composition of claim 1 , comprising:
contacting dried date pit particles with an organic solvent to remove oils and form de-oiled date pit particles;
mixing the de-oiled date pit particles with a base and water to form an alkaline mixture;
subjecting the alkaline mixture to a freeze/thaw process and optionally adding an acid to form a freeze/thaw mixture comprising the treated date pit particles in water; and
adding the freeze/thaw mixture to the viscosifier and the aqueous base fluid to form the drilling fluid composition.

15. The method of claim 14 , wherein the organic solvent is at least one selected from the group consisting of pentane, hexane, methanol, and ethanol.

16. The method of claim 14 , wherein the base is sodium hydroxide and the acid, when added, is acetic acid or sulfuric acid.

17. The method of claim 14 , wherein the freeze/thaw process comprises
subjecting the alkaline mixture to a temperature of −20° C. or below for at least 4 hours to form a frozen mixture,
thawing the frozen mixture at a temperature of 20-50° C.; and
agitating for at least 15 minutes to form the freeze/thaw mixture.

18. A process for drilling a subterranean geological formation, comprising:
drilling the subterranean geological formation with a drill bit to form a wellbore; and
injecting the drilling fluid composition of claim 1 into the subterranean geological formation through the wellbore.

19. The process of claim 18 , wherein the treated date pit particles are ii) treated with a base, and the drilling fluid composition is injected into the subterranean geological formation through the wellbore to maintain a pressure in the wellbore that is higher than a static pressure of the subterranean geological formation.

20. The process of claim 18 , wherein the treated date pit particles are ii) treated with both a base and an acid, and the drilling fluid composition is injected into the subterranean geological formation through the wellbore to maintain a pressure in the wellbore that is lower than a static pressure of the subterranean geological formation.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Adewole Jimoh K
• Najimu Musa O

Classifications

• C09K8/08 Primary

  containing natural organic compounds, e.g. polysaccharides, or derivatives thereof · CPC title

• C09K8/145 Primary

  characterised by the composition of the clay · CPC title

• C09K2208/04

  Hulls, shells or bark containing well drilling or treatment fluids · CPC title

• C09K8/18

  characterised by the organic compounds · CPC title

• E21B21/003

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