Oil-Swellable, Desolvated Polymer Gels and Methods of Using the Same for Preventing Loss of Non-Aqueous Wellbore Fluids to the Subterranean Formation

Patent metadata

Field	Value
Publication number	US-2018334608-A1
Application number	US-201815963266-A
Country	US
Kind code	A1
Filing date	Apr 26, 2018
Priority date	May 17, 2017
Publication date	Nov 22, 2018
Grant date	—

Abstract

An oil-swellable gel lost circulation material (LCM) formed from an elastomeric polymer and a crosslinker amine is provided. The LCM may include gel pieces cut from gel strands formed from an elastomeric polymer and a crosslinker amine. The oil-swellable gel LCM composition may be formed by mixing an elastomeric polymer solution with a crosslinker amine and heating the mixture to form a crosslinked gel. The gel may be extruded through a die having orifices into a non-solvent and allowed to desolvate in the presence of the non-solvent. The gel strands may be dried and cut into gel pieces to form an LCM. The resulting LCM may swell when introduced to a loss circulation zone in the presence of a non-aqueous fluid such as a drilling mud or component of a drilling mud.

First claim

1 . A method to control lost circulation in a well, comprising:
introducing a lost circulation material (LCM) into a wellbore such that the LCM contacts a lost circulation zone and reduces a rate of lost circulation into the lost circulation zone as compared to a period before introducing the LCM, the LCM comprising a plurality of desolvated particulate gel pieces comprising an elastomeric polymer crosslinked using a crosslinker, the crosslinker comprising an amine, wherein the elastomeric polymer includes a first monomer comprising an olefinically unsaturated hydrocarbon monomer and a second monomer comprising an epoxy pendant group, wherein introducing the LCM into the wellbore comprises:
mixing the LCM with a non-swellable non-aqueous solvent such that the LCM is in an unswollen form;
pumping the non-swellable non-aqueous solvent and LCM into the lost circulation zone; and
displacing the non-swellable non-aqueous solvent with a swelling non-aqueous fluid, such that the plurality of desolvated particulate gel pieces swell within the loss circulation zone.

2 . The method of claim 1 , wherein the non-swellable non-aqueous solvent comprises an alcohol, a ketone, or an alcohol ether.

3 . The method of claim 1 , wherein the second monomer comprises a glycidyl acrylate.

4 . The method of claim 3 , wherein the elastomeric polymer comprises ethylene/methyl acrylate/glycidyl methacrylate terpolymer.

5 . The method of claim 1 , wherein the amine comprises a polyamine comprising at least two primary amine groups.

6 . The method of claim 5 , wherein the amine comprises at least one of: tetraethylene pentaamine (TEPA), triethylene glycol diamine (TEGDA), polyoxypropylene triamine (POPTA), and diethyltoluenediamine (DETDA).

7 . The method of claim 1 , wherein a diameter of each of the plurality of gel pieces is in a range of 1 millimeter (mm) to 5 mm.

8 . The method of claim 1 , wherein a length of each of the plurality of gel pieces is in a range of 2 millimeter (mm) to 15 mm.

9 . The method of claim 1 , wherein the swelling non-aqueous fluid comprises a synthetic-based mud (SBM) or an oil-based mud (OBM).

10 . The method of claim 1 , wherein the swelling non-aqueous fluid comprises a non-aqueous solvent comprising an aromatic hydrocarbon or an aliphatic hydrocarbon.

Assignees

• Saudi Arabian Oil Co

Inventors

• Reddy B Raghava
• Hilfiger Matthew

Classifications

• C08F8/32

  by reaction with amines · CPC title

• E21B21/003

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

• C08J2323/36

  by reaction with nitrogen-containing compounds, e.g. by nitration · CPC title

• C09K8/502 Primary

  Oil-based compositions · CPC title

• C09K8/487

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