Invert emulsion drilling fluid containing a hygroscopic liquid and a polymeric suspending agent
AssigneeHalliburton Energy Services, Inc.
InventorsVikrant WAGLE, Shadaab MAGHRABI
Life of this patent
Estimating the term…
Abstract
An invert emulsion drilling fluid comprises: an external phase, wherein the external phase of the drilling fluid comprises a hydrocarbon liquid; an internal phase, wherein the internal phase of the drilling fluid comprises a hygroscopic liquid; and a suspending agent, wherein the suspending agent is a polymer comprising urea linkages or urea and urethane linkages. The hygroscopic liquid comprises a salt and a suitable solvent or comprises an alcohol. The drilling fluid can exclude an organophilic clay or organophilic lignite. A method of using the invert emulsion drilling fluid comprises: introducing the drilling fluid into at least a portion of a subterranean formation.
Claims21
An invert emulsion drilling fluid comprising:
- an external phase,
- wherein the external phase of the drilling fluid comprises a hydrocarbon liquid;
- an internal phase,
- wherein the internal phase of the drilling fluid comprises a hygroscopic liquid;
- and
- a suspending agent,
- wherein the suspending agent is a polymer, wherein the polymer comprises urea linkages.
An invert emulsion drilling fluid comprising:
- an external phase,
- wherein the external phase of the drilling fluid comprises a hydrocarbon liquid;
- an internal phase,
- wherein the internal phase of the drilling fluid comprises a hygroscopic liquid,
- wherein the hygroscopic liquid is selected such that the drilling fluid has an activity less than or equal to the amount needed to obtain a shale retention value of greater than 90%, when tested on a shale formation sample, and
- wherein the drilling fluid does not contain an organophilic clay or organophilic lignite.
Dependencies are inferred from the claim text.