An object of the present invention is to provide a salt water thickener that uniformly (favorably) disperses ultrafine cellulose fibers even in a liquid containing a salt (electrolyte). The salt water thickener comprises ultrafine cellulose fibers and a water-soluble polymer and can thereby uniformly disperse the ultrafine cellulose fibers even in a liquid containing a salt. The salt water thickener of the present invention is uniformly dispersed even in a liquid containing a salt and therefore exerts a high viscosity. The salt water thickener of the present invention can also be used as an additive for a fluid. The salt water thickener of the present invention can be used for purposes, for example, subterranean formation processing.

A treatment fluid includes a carrier fluid having a pH less than 6.5, a polysaccharide gelling agent, and a pH modifier which decomposes and/or releases a pH increasing agent under downhole formation conditions to increase the pH of the fluid within the formation, Methods of using the treatment fluid include introducing the treatment fluid in a well bore and allowing the pH modifier to decompose and/or release the pH increasing agent to increase the pH of the wellbore treatment fluid above 7.

The present invention relates to a foam containing water, between 5 and 30 wt % on total weight of the foam of a chelating agent selected from the group of glutamic aid N,N-diacetic acid or a salt thereof (GLDA), aspartic acid N,N-diacetic acid or a salt thereof (ASDA), methylglycine N,N-diacetic acid or a salt thereof (MGDA), N-hydroxyethyl ethylenediamine-N,N′,N′-triacetic acid or a salt thereof (HEDTA), a foaming agent, and at least 25 vol % on total volume of the foam of a gas, and having a pH of between 2 and 5, to a viscosified composition containing water, between 5 and 30 wt % on total volume of the composition of a chelating agent selected from the group of glutamic aid N,N-diacetic acid or a salt thereof (GLDA), aspartic acid N,N-diacetic acid or a salt thereof (ASDA), methylglycine N,N-diacetic acid or a salt thereof (MGDA), N-hydroxyethyl ethylenediamine-N,N′,N′-triacetic acid or a salt thereof (HEDTA), and at least 0.01 wt % on total weight of the composition of a viscosifying agent, and having a pH of between 2 and 5, and to a process for treating a subterranean formation comprising introducing the above foam or viscosified composition into the formation.

A fines-fixing agent that has improved compatibility with organic complexed borate fracturing fluids is disclosed. Existing fines fixing agents have a high concentration of unreacted caustic that results in a product pH of approximately 12. This high pH affects the crosslinker and the overall fracturing fluid system stability, promoting precipitation of the organic crosslinker. These effects can be mitigated by neutralizing the fines fixing agents with an acid such as hydrochloric or acetic acid to a pH of 6 or lower.

Shale inhibiting additives for subterranean drilling and/or treatment fluids that include polyvinyl alcohol (PVA) are provided. In some embodiments, the methods include: providing a treatment fluid including an aqueous base fluid and a shale inhibiting additive including polyvinyl alcohol; introducing the treatment fluid into at least a portion of a subterranean formation to contact at least a portion of the subterranean formation that comprises shale; and allowing the shale inhibiting additive to interact with the shale in the subterranean formation to at least partially inhibit the shale.

Fracturing fluid compositions including a base fluid including a high TDS produced and/or flow back water, brackish water, RO reject water, clear brine, and mixtures thereof with or without added fresh water and systems, and methods for making and using same, where the method includes: (a) adding a first buffer to adjust the pH of a base fluid to an acidic pH, (b) adding a hydratable polymer or polymer slurry to the base fluid to form a hydratable polymer fracturing fluid, (c) adding a cross-linking composition to the hydratable polymer fracturing fluid to form a pre-cross-linked fracturing fluid, and (d) if needed, adding a second buffer to the pre-cross-linked fracturing fluid to adjust the pH of the pre-cross-linked fracturing fluid to form a viscosified fracturing fluid having a crosslinked structure.

A method of spearheading an acid into a wellbore is adapted to avoid the gelation of a friction reducer polymer. The method comprises injecting a synthetic or modified acid composition down a wellbore, the composition comprising: a synthetic or modified acid; a solvent; and a chelating agent. Optionally the composition may comprise a corrosion inhibitor package. The method further includes allowing sufficient time for the synthetic or modified acid composition to react with material which require acidic treatment and injecting a fracturing composition comprising a liquid and a friction reducing polymer down the wellbore.

Various embodiments disclosed related to compositions and methods of using the same for treating subterranean formations. In various embodiments, the present invention provides a method of treating a subterranean formation. The method includes placing in a subterranean formation a composition that includes a viscosifier and that also includes a hydrophobically-modified polymer including at least one nitrogen-containing repeating unit.

A method for wellbore treatment. The method including preparing an encapsulated treatment agent via polymerization, feeding the encapsulated treatment agent into the wellbore, delivering the encapsulated treatment agent to a desired depth within a formation in the wellbore, activating an acoustic or an electromagnetic source at the desired depth within the formation, and generating an acoustic field or an electromagnetic field. The acoustic field or electromagnetic field activates the encapsulant thereby releasing the treatment agent into the wellbore and a desired depth.

Degradable material for treatment fluids for use in fluid loss control, diversion, and plugging operations, methods of preparing the degradable material, and methods of using the degradable material in treatment fluids are disclosed. The degradable materials are polymer-based solid acid precursor particles that have been partially or fully coated with an anti-caking agent to prevent agglomeration of the polymer-based solid acid precursor particles during storage and transport. These coated polymer-based solid acid precursor particles can then be added to a variety of treatment fluids to temporarily create a physical barrier to fluid flow before degrading and generating acids that can be used in other treatment operations. This degradable coated polymer-based solid acid precursor additive can be combined with other traditional downhole additives such surfactants, viscosifiers, and biocides, allowing for a wide variety of applications in hydrocarbon reservoirs.