Abstract: A salt-tolerant polymer microsphere plugging agent and a preparation method thereof, the agent being made of white oil, fumed silica, acrylamide monomer, acrylic acid, sorbitan fatty acid ester, N,N?-methylene bisacrylamide, ammonium persulfate, sodium bisulfite, hydrophilic surfactant and water. The present general inventive concept synthesizes salt-tolerant polymer microspheres with ultra-low interfacial tension by adopting inverse phase emulsion polymerization. The prepared polymer microsphere plugging agent is a new type of polymer microspheres with ultra-low interfacial tension, such that the tension can reach 4.3×10?3 mN/m, and the salt tolerance can reach 50000 mg/L salinity, which improves the problem of low interfacial tension and poor salt tolerance in existing polymer microspheres.

Abstract: The subject invention provides multi-functional biochemical compositions, as well as their use in enhancing oil recovery from an oil-bearing subterranean formation. Advantageously, the compositions and methods of the subject invention are operationally-friendly, cost-effective, and environmentally-friendly. More specifically, in preferred embodiments, the subject invention provides a multi-functional composition for enhanced oil recovery (EOR) comprising one or more surfactants, one or more chelating agents, and one or more solvents.

Abstract: A scale inhibitor includes an amount of hydroxyethylidene diphosphonic acid (HEDP), and an amount of hydroxyapatite. The amounts are combined to form a composition that is long lasting, high activity and completely dissolvable. The composition has a preferred particle size of less than 200 nm. Dicalcium phosphate, tricalcium phosphate, bone and/or bone ash may be used in place of hydroxyapatite.

Abstract: Methods of reducing drag in a flowing hydrocarbon include introducing to the flowing hydrocarbon an amount of a solid drag reducing additive effective to improve the flow, the solid drag reducing additive including a polymer particle prepared from at least one polar monomer and a percent by weight (wt %) of liquid of 50 wt % or less. Methods also include producing a solid drag reducing additive that includes forming a polymer from at least one polar monomer by emulsion polymerization; and disrupting the emulsion by adding at least one demulsifier and at least one anti-blocking agent to form the solid drag reducing additive. Compositions include a solid drag reducing additive comprising a polymer prepared from at least one polar monomer and having an average particle size in a range of about 100 ?m to about 500 ?m, wherein the solid drag reducing additive comprises less than 50 wt % of liquid.

Abstract: Provided is a method making it possible to ensure a gradual release of polymer chains within a liquid medium, the method comprising bringing the liquid medium into contact with specific solid objects formed by polymer chains soluble in the medium and carrying hydrophobic side groups ensuring physical crosslinking between the polymer chains within the solid objects. The released chains may in particular be used as inhibitors of the formation of inorganic or organic deposits (scale inhibitors) within a liquid medium, typically in the field of oil extraction.

Abstract: A drilling fluid and method for drilling in a coal containing formation. The method includes: providing a mixed metal-viscosified drilling fluid including at least 1% potassium salt; circulating the drilling fluid through the well; and drilling into a coal seam.

Abstract: Expandable tube members that are fabricated from a composite material that includes a structural plastic, which structural plastic includes phase change materials that undergo a permanent expansion upon exposure to wellbore conditions. This permanent expansion of the structural plastic causes the expandable tube member to expand radially and/or longitudinally without the use of an expansion tool. The expandable tube member can be used to control fluid loss, patch wells, stabilize a formation in a wellbore, enhance flow, provide sand screening, and repair damaged pipes, casings, or liners.

Abstract: A method of drilling in a subterranean formation. A method may include providing a direct emulsion drilling fluid comprising an aqueous fluid, an oil, and a polysorbate emulsifier; circulating the direct emulsion drilling fluid from a surface, through a wellbore, and back to the surface; and extending the wellbore in the subterranean formation while circulating the direct emulsion drilling fluid.

Abstract: 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 utilization in forming the barrier is provided.

Abstract: Well treatment operation comprises introducing nanosized particulates into a formation. The nanosized particulates are synthesized by combining PMIDA, a calcium source, a pH adjusting agent, and an aqueous medium. This combination results in a degradable (i.e., dissolvable) solid that can be used in heterogeneous formations like shale type rock reservoirs, as well as sedimentary rock formations like clastic, siliclastic, sandstone, limestone, calcite, dolomite, and chalk formations, and formations where there is large fluid leak-off due to stimulation treatments. The disclosed particulates may also be used for acidizing treatments in mature fields and deep water formations commonly characterized by high permeability matrices. The solubility of the particulates advantageously allows the material to act as a temporary agent having a lifespan that is a function of temperature, water flux, and pH, making it adaptable to various reservoir conditions with minimal to no risk of adverse effects on the reservoir.

Abstract: Quaternary ammonium compounds and methods of using such compounds to, for example, break oil-in-water emulsion treatment fluids are provided. In some embodiments, such methods include introducing a quaternary ammonium compound into an oil-in-water emulsion treatment fluid that comprises an oleaginous phase and an aqueous phase; and centrifuging at least the portion of the oil-in-water emulsion treatment fluid to separate at least a portion of the oil-in-water emulsion treatment fluid into an oleaginous fluid and an aqueous fluid.

Abstract: Amidoamine-based gemini surfactants having dual chains connected via an alkenylene or alkynylene linker. Each chain contains a quaternary ammonium head group and an ethoxylated alkyl tail. A water-based drilling fluid containing the gemini surfactant is also provided. As examined by linear swelling and free swelling tests, the gemini surfactant is effective in reducing clay swelling.

Abstract: A method of removing calcium-containing water-based filter cake from a wellbore involving contacting the calcium-containing filter cake with a biodegradable acid solution of water, hydrochloric acid, formic acid, citric acid, and a surfactant. The method is performed at a pressure of 200 to 400 psi and a temperature of 50 to 125° C. The method removes calcium-containing filter cake made of water, calcium carbonate, a polymer or starch and a clay. The method meets industry standard steel corrosion rates of less than 0.049 lb/ft2 per day. Also disclosed is a biodegradable acid solution of water, hydrochloric acid, formic acid, citric acid, and a surfactant that meets OECD 301B thresholds for ready biodegradability.

Abstract: The subject invention relates to methods for post-primary oil recovery that utilize multiple mechanisms of action, wherein biochemical-producing microbes are injected into an oil well in a certain predetermined order, based on, for example, the metabolites and by-products they are capable of producing. Preferably, gas-, acid- and/or solvent-producing microbe such as a Clostridium bacterium, is injected into the well first, followed by a biosurfactant and/or biopolymer-producing microbe, such as Bacillus subtilis, Bacillus licheniformis and/or a combination thereof.

Abstract: A surfactant of formula (I) wherein each of R1 and R2 are independently a hydrogen, an optionally substituted alkyl, an optionally substituted cycloalkyl, or an optionally substituted arylalkyl, R3 and R4 are independently an optionally substituted alkyl, an optionally substituted cycloalkyl, or an optionally substituted arylalkyl, x is an integer in a range of 2-8, y is an integer in a range of 1-15, z is an integer in a range of 4-10, n is an integer in a range of 2-5, and A is one of a carboxybetaine group, a sulfobetaine group, or a hydroxy sulfobetaine group. An oil and gas well servicing fluid containing the surfactant and methods of servicing an oil and gas well are also described.

Abstract: The present invention relates to the field of oil extraction. More specifically, it relates to a particular polymerization process, which provides access to formulations of polymers that may be used in particular for modifying rheology and fluid loss control during extraction operations and that have a better heat stability.

Abstract: A composition for inhibiting corrosion in hydrocarbon wells includes a pyranopyrazole derivative. The pyranopyrazole derivative includes a pyrazole moiety, a dihydropyran moiety, and a phenyl moiety. The dihydropyran moiety is bound to the pyrazole moiety. The phenyl moiety is bound to the dihydropyran moiety. The composition can be flowed into a wellbore formed in a subterranean formation, thereby inhibiting corrosion in the wellbore.

Abstract: Compounds are identified that act as crystallization suppressants when added to clear brine fluids, significantly lowering the true crystallization temperatures of the brines, and allowing for higher salt content in clear brine fluids. The crystallization suppressants of the invention also allow for the preparation of higher density zinc free brines. Crystallization suppressant blends are also identified that allow for the preparation of high density clear brine fluids with lower viscosities.

Abstract: A method of dissolving a gas hydrate in a pipeline includes introducing a gas hydrate dissolving solution into the pipeline and allowing the gas hydrate dissolving solution to at least partially dissolve the gas hydrate in the pipeline. The gas hydrate dissolving solution includes cesium formate, potassium formate, or both, and has a flash point of greater than 50° C.

Abstract: Proppant particles formed from slurry droplets and methods of use are disclosed herein. The proppant particles can include a sintered ceramic material and can have a size of about 80 mesh to about 10 mesh and an average largest pore size of less than about 20 microns. The methods of use can include injecting a hydraulic fluid into a subterranean formation at a rate and pressure sufficient to open a fracture therein and injecting a fluid containing a proppant particle into the fracture, the proppant particle including a sintered ceramic material, a size of about 80 mesh to about 10 mesh, and an average largest pore size of less than about 20 microns.