Disclosed are compositions and methods for use in oil and gas operations.

Disclosed are compositions and methods for use in oil and gas operations.

A method includes providing an injection well extending from a surface into a formation and alternatingly pumping a foam injectant and a gel injectant into the injection well, wherein the foam injectant includes a liquid phase with a surfactant and water and a gas phase and the gel injectant includes a water-soluble polymer and a crosslinker. The foam injectant and the gel injectant are injected at separate times and sequentially.

A method of reducing shear recovery time of a viscosifying surfactant fluid system that includes introducing a viscosifying surfactant fluid system into a subterranean formation, wherein the fluid includes a major portion of a surfactant and a hydrophobically-modified associative polymer in a concentration sufficient to shorten the shear recovery time of the fluid system compared to the shear recovery time of the fluid system without the polymer.

There is provided synthetic proppants, and in particular polysilocarb derived ceramic proppants. There is further provided hydraulic fracturing treatments utilizing these proppants, and methods of enhance hydrocarbon recovery.

There is provided synthetic proppants, and in particular polysilocarb derived ceramic proppants. There is further provided hydraulic fracturing treatments utilizing these proppants, and methods of enhance hydrocarbon recovery.

The present disclosure is directed to polyanionic surfactants, surfactant mixtures, compositions derived thereof, and uses thereof in hydrocarbon recovery. Methods of making polyanionic surfactants are also described.

Provided herein are liquid polymer (LP) compositions comprising a synthetic (co)polymer (e.g., an acrylamide (co)polymer), as well as methods for preparing aqueous polymer solutions by combining these LP compositions with an aqueous fluid. The resulting aqueous polymer solutions can have a concentration of a synthetic (co)polymer (e.g., an acrylamide (co)polymer) of from 50 to 15,000 ppm, and a filter ratio of 1.5 or less at 15 psi using a 1.2 μm filter. Also provided are methods of using these aqueous polymer solutions in oil and gas operations, including enhanced oil recovery.

Provided herein are liquid polymer (LP) compositions comprising a synthetic (co)polymer (e.g., an acrylamide (co)polymer), as well as methods for preparing aqueous polymer solutions by combining these LP compositions with an aqueous fluid. The resulting aqueous polymer solutions can have a concentration of a synthetic (co)polymer (e.g., an acrylamide (co)polymer) of from 50 to 15,000 ppm, and a filter ratio of 1.5 or less at 15 psi using a 1.2 μm filter. Also provided are methods of using these aqueous polymer solutions in oil and gas operations, including enhanced oil recovery.

The invention is directed to stable and labile crosslinked water swellable polymeric microparticles that can be further gelled by covalent crosslinking in a transamidation reaction, methods for making same, and their various uses in the hygiene and medical arts, gel electrophoresis, packaging, agriculture, the cable industry, information technology, in the food industry, papermaking, use as flocculation aids, and the like. More particularly, the invention relates to a composition comprising expandable polymeric microparticles having labile crosslinkers and stable crosslinkers, said microparticle mixed with a fluid and an unreacted tertiary crosslinker comprising PEI or other polyamine based tertiary crosslinker that is capable of further crosslinking the microparticle on degradation of the labile crosslinker and swelling of the particle, so as to form a stable gel. A particularly important use is as an injection fluid in petroleum production, where the expandable polymeric microparticles are injected into a well and when the heat and/or pH of the well cause degradation of the labile crosslinker and when the microparticle expands, the tertiary crosslinker crosslinks the polymer to form a stable gel, thus diverting water to lower permeability regions and improving oil recovery.