A method of forming a barrier to overcome lost circulation in a subterranean formation. The method includes injecting a polymer-sand nanocomposite into one or more lost circulation zones in the subterranean formation where the polymer-sand nanocomposite is formed from sand mixed with a polymer hydrogel. Further, the polymer hydrogel includes a hydrogel polymer, an organic cross-linker, and a salt. The sand additionally comprises a surface modification. The associated method of preparing a polymer-sand nanocomposite lost circulation material for utilisation in forming the barrier is provided.

Methods of capturing carbon dioxide in a wellbore can include installing a sealing element in the wellbore. The sealing element swells in the presence of carbon dioxide and can be used for capturing the carbon. The sealing element can include a carbon-swelling material, such as a carbon-swelling polymers, metal-based materials, or combinations of elastomeric polymers and metal-based materials. The sealing element can also include combinations of different carbon-swelling materials, fillers or other compounds, and materials that are not carbon swellable. The sealing element can create a seal, form an anchor, or create a seal and form an anchor in the wellbore after swelling.

The embodiments described herein generally relate to methods and chemical compositions for use with wellbore treatment processes. In one embodiment, a composition is provided comprising a cementitious material, a drilling fluid, or combinations thereof, and an additive composition comprising one or more components selected from the group of an aqueous insoluble lignin, a coke fine, a random tetracopolymer having the formula styrene-butadiene-acrylic-fumaric acid, a polyvinyl acetate, a surfactant composition, and combinations thereof.

Methods and compositions for using shale inhibitor additives in subterranean formations, and specifically, to dried shale inhibitor additives and methods for use are provided. In one embodiment, the methods include providing a dried shale inhibitor additive that includes a precipitate of at least one liquid amine shale inhibitor; allowing at least a portion of the dried shale inhibitor additive to dissolve in a treatment fluid including an aqueous base fluid; and introducing the treatment fluid into a wellbore penetrating at least a portion of a subterranean formation.

Methods and compositions for using shale inhibitor additives in subterranean formations, and specifically, to dried shale inhibitor additives and methods for use are provided. In one embodiment, the methods include providing a dried shale inhibitor additive that includes a precipitate of at least one liquid amine shale inhibitor; allowing at least a portion of the dried shale inhibitor additive to dissolve in a treatment fluid including an aqueous base fluid; and introducing the treatment fluid into a wellbore penetrating at least a portion of a subterranean formation.

A mud loss treatment drilling tool includes the tool having an upper tooljoint to a lower end of an above drill pipe string, one or more tanks with a through channel for a drilling fluid flow, a lower tooljoint connected to a BHA assembly at least comprising a drill bit; the tank arranged for holding a swellable sealant agent; the swellable sealant agent arranged for mixing with water to swell; the tank provided with an outlet to the through channel for the swellable sealant agent, so as for, when an undesired mud loss is detected, for flushing all or part of the swellable sealant agent into the through channel, so as for a mixture of the swellable agent and the water to start reacting to swell during the time it takes the mixture to reach a fracture extending from a well under drilling by said BHA, so as for continuing to swell and block the fracture to stop the undesired mud loss.

A method for reducing lost circulation in a subterranean formation. The method includes providing a treatment fluid comprising a base fluid and a lost circulation material comprising cane ash. The treatment fluid is introduced into a wellbore within the subterranean formation such that at least a portion of the cane ash bridges openings in the subterranean formation to reduce loss of fluid circulation into the subterranean formation.

A method for reducing lost circulation in a subterranean formation. The method includes providing a treatment fluid comprising a base fluid and a lost circulation material comprising brown mud. The treatment fluid is introduced into a wellbore within the subterranean formation such that at least a portion of the brown mud bridges openings in the subterranean formation to reduce loss of fluid circulation into the subterranean formation.

A method comprising introducing a treatment fluid into a subterranean formation, wherein the treatment fluid comprises a base fluid and a crosslinked polymer, the crosslinked polymer comprising reactants of a first repeating unit, a second repeating unit, and a crosslinker that react to form the crosslinked polymer, wherein the first repeating unit is a sulfonic acid-containing monomer present from 50% to 99% by weight of the reactants, wherein the second repeating unit selected from the group consisting of an N-vinyl amide-containing monomer, a terminal double bond-containing monomer, and any combination thereof, and is present from 1% to 50% by weight of the reactants, and wherein the crosslinker comprises at least two olefinic bonds.

Certain invert emulsion treatment fluids for use in subterranean formations are provided. In certain embodiments, the methods comprise: providing an invert emulsion treatment fluid that comprises an oleaginous external phase, and an internal phase that comprises one or more alcohols and one or more polar organic compounds that are soluble in the internal phase; and introducing the treatment fluid into at least a portion of a subterranean formation.