The present technology relates to a process for enhancing hydrocarbon production from a shale formation. In particular, the present technology relates to a process wherein a treatment fluid comprising a water soluble delayed release carbonate-dissolving agent is introduced into the shale formation after or as part of a hydraulic fracturing process. The present technology also relates to a treatment fluid that can be used in such a process.

The present invention relates to a process fluid comprising an environmentally friendly biostabiliser, for industrial scale use in the Earth's crust, preferably for use in oil and natural gas extraction, in particular in hydraulic fracturing. The biostabiliser is characterised in that it comprises at least one organic acid, or a salt, alcohol or aldehyde thereof, wherein the at least one organic acid is selected from the group consisting of hop acids, resin acids, fatty acids and mixtures thereof. The biostabiliser is preferably a mixture of hop extract, rosin and myristic acid. The invention further relates to corresponding application and production methods.

Certain particulates of encapsulated treatment chemicals, and methods of and systems for their use in subterranean formations, are provided. In one embodiment, the methods comprise: providing a plurality of treatment particulates, at least one of which comprising a polymer matrix that comprises and/or encages at least one treatment chemical and a coating disposed around an outer surface of the polymer matrix; and introducing the treatment particulates into a well bore penetrating at least a portion of a subterranean formation.

The invention relates to synthetic nanocompounds in the form of microparticles that allow major deformations before breaking and are especially useful for preparing low-density synthetic propping agents to be used in non-conventional oil and gas extraction processes (fracking). The invention also describes the process for obtaining said nanocompounds, propping agents and fracturing fluids for oil and gas extraction processes.

Particulates, such as proppants, that are coated with a coating agent selected from the group consisting of: organosilanes, organosiloxanes, polysiloxanes, long carbon chain hydrocarbon amines containing no silicon or fluoro-based groups in the molecule, amine functionalized polyolefins and polymerizable natural oils; and a chemical additive selected from the group consisting of: a scale inhibitor, a biocide, and an H.sub.2S scavenger. The coating agent controls the release of the additive from the particulate surface into surrounding fluid, providing a slow release that promotes the long lasting effect of the additive. The coated particulates have use in oilfield applications such as hydraulic fracturing operations, gravel pack operations, and in water treatment processes.

A system for slowly releasing an oil-soluble well treatment agent into a well or a subterranean formation includes a composite of the oil-soluble well treatment agent associated with a second component. The amount of the oil-soluble well treatment agent in the composite is from 20 to 35 weight percent and the average particle size of the oil-soluble well treatment agent in the composite is less than or equal to 1 micrometer. The composite may further contain a water-soluble well treatment agent.

A method of treating a well or a subterranean formation with an aqueous treatment fluid containing one or more oil-soluble, water-insoluble well treatment agents. The fluid includes an aqueous dispersion containing the well treatment agent in an amount from 25 to 60 weight percent. The volume average particle diameter of the oil-soluble well treatment agent in the fluid may be less than or equal to 2.5 microns. The fluid may further contain a water-soluble well treatment agent.

A treatment fluid comprises: a liquid fluorinated compound; and at least one additive, wherein the additive: (A) comprises carbon and at least one fluorine functional group; and (B) is soluble or dispersible in the liquid fluorinated compound. A method of treating a portion of a well comprises: forming the treatment fluid; and introducing the treatment fluid into the well.

Disclosed are compositions derived of mixtures of choline ion salts (typically choline chloride) in aqueous solution with suspended particulates of sparingly soluble borate minerals or with alkali or alkaline earth borate salts, boric acid and its ester derivatives and salts, or other aqueous soluble borate forms. These compositions are useful as cross-linkers for polysaccharides and other biopolymers and particularly as used in subterranean treatment fluids for completion and stimulation of oil and gas wells. Advantages of the compositions are the combination into a single package of the properties of clay stabilizing actives (choline ion) and crosslinking actives (borates, etc.), in relatively high concentrations, and these compositions are easy to handle, being stable and pumpable at low temperatures, and with attractive environmental profiles. Also disclosed are the analogous choline solutions mixed with metallic cross-linking ions know in the art such as Zr.sup.+, Ti.sup.4+, Al.sup.3+, & Fe.sup.3+.

A well treatment material for introduction into a subterranean formation is provided. The well treatment material can include a biocide collected onto a sorbent. The biocide can be capable of being desorbed at a generally constant rate over an extended period of time into the subterranean formation. The biocide can be an oxidizing biocide or a non-oxidizing biocide. The sorbent material can include one or more of an absorbent material and an adsorbent material. The biocide can be chlorine dioxide. The sorbent can be one or more of silica gel and graphite.