56 results about "Water-in-water emulsion" patented technology

This invention relates to compositions and methods for treating subterranean formations, in particular, oilfield stimulation compositions and methods using water-in-water polymer emulsions to uniformly dissolve a rheologically active polymer, such as a thickener or friction reducer, in the treatment fluid. The emulsions have a low viscosity and are easily pumped for mixing into a treatment fluid, where upon dilution with an aqueous medium, the polymer is easily hydrated without forming fish-eyes. The partitioning agent in the water-in-water emulsion does not generally affect the rheology of the treatment fluid. The invention also relates to further processing of the emulsion by wet grinding, high shear mixing and/or heating to enhance the hydration rate in the preparation of the well treatment fluid.

Methods and apparatus for forming a fluid for use within in a subterranean formation including crosslinking a polymer along the surface of microspheres in a water-in-water emulsion and introducing the microspheres into the subterranean formation. Methods and apparatus for forming a fluid for use within in a subterranean formation including crosslinking a polymer along the surface of microspheres in a water in water emulsion, isolating the microspheres from the emulsion, and introducing the microspheres into the subterranean formation. Methods and apparatus for forming a fluid to treat a subterranean formation including introducing a crosslinkable polymer, partitioning agent, and crosslinker into a solvent, crosslinking the crosslinkable polymer, isolating beads of the crosslinkable polymer from the partitioning agent, introducing the beads into a fluid for treating a subterranean formation.

The invention discloses a synthesizing method of cationic polyacrylamide 'water-in-water' emulsion, which is characterized by the following: adopting inorganic solution as dielectric with specific viscosity number is 30-90ml/g low-molecular cationic polymer solution as stabilizer; copolymerizing free radical of cationic monomer with double bond and non-ion monomer to form the product with grain size less than 1um; fitting for disposing urban effluent, oil-field effluent and paper-making domain.

The invention relates to a cationic acrylamide copolymer aqueous emulsion-water and the method for preparing the same. The compound comprises 5-25 wt% of cationic polymer, 1.0-15 wt% of polymer stabilizer and 15-32 wt% inorganic salt. Said active cationic polymer comprises 72.8-90 mol% of at least one water-soluble monomer (A), 10-26 mol% of at least one cationic monomer (B), and 0.2-1.0 mol% of at least one hydrophobic monomer (C), and said polymer is prepared through free radical polymerization with pH being 3-8. The monomer (A) (B) possesses general formula respectively, monomer (c) is C1-C8 dialkyl ester of itaconic acid or C1-C32 alkyl ester of acroleic acid or C1-C32 alkyl ester or diene monomer of methacrylic acid. The method is multi-stage, and it can reduce polymerization system viscosity, increase active material content and stability of aqueous emulsion-in-water, which is characterized by high concentration, low cost, good fluidity and easiness for treatment.

The present invention relates to a non-amphiphile-based water-in-water emulsion composition. The non-amphiphile-based water-in-water emulsion composition includes a water-soluble polymer, a non-amphiphilic lyotropic mesogen encapsulated by the water-soluble polymer; and water. In one embodiment, the non-amphiphilic lyotropic mesogen includes, without limitation, a lyotropic chromonic liquid crystal, and more specifically disodium cromoglycate (DSCG). In another embodiment, the water-soluble polymer can include, without limitation, a polyacrylamide, a polyol, a polyvinylpyrrolidone, a polysaccharide, or a water-soluble fluoride-bearing polymer. The present invention also relates to a porous hydrogel made with the use of the non-amphiphile-based water-in-water emulsion. The present invention further relates to using the emulsion and hydrogel for various applications.

This invention relates to compositions and methods of treating a subterranean formation penetrated by a well bore including providing a treatment composition comprising a rheological polymer, a partitioning agent, a charged polyelectrolyte, and a first liquid medium, forming a stabilized heterogeneous mixture comprising a dispersed rheological polymer-rich phase and a partitioning agent-rich phase, and injecting the treatment fluid into the well bore. The invention relates to methods and compositions for preparing a well treatment fluid, including mixing polyethylene glycol partitioning agent, a charged polyelectrolyte, a first aqueous medium, and one or more rheological polymers selected from the group consisting of guar, modified guar, cellulose, modified cellulose, heteropolysaccharide, heteropolysaccharide derivative, or polyacrylamide, to hydrate the one or more polymers and form a water-in-water emulsion, and mixing the water-in-water emulsion with a second aqueous medium to form a well treatment fluid.

A method of plugging a fracture in a subterranean formation which includes placing into the fracture a composition comprising microspheres or microbeads, wherein the microspheres are created by surface crosslinking of droplets in a water-in-water emulsion. Such microspheres may form a filter cake in the formation. The microspheres may include a chemical agent to be released when the microspheres dissolve.

The invention discloses a hydrophobic associated anionic polyacrylamide water-in-water emulsion and a preparation method thereof. The hydrophobic associated anionic polyacrylamide water-in-water emulsion is prepared by initiating and polymerizing a water solution system which comprises inorganic salt, nonionic monomers, anionic monomers, hydrophobic monomers, a stabilizer, a chelating agent and deionized water through an initiating agent. The hydrophobic associated anionic polyacrylamide water-in-water emulsion can be quickly dispersed and dissolved in water, has a high viscosity-enhancing capability and a high salt-resistant capability, and has a wide application prospect in the oil and gas exploitation field.

The invention discloses an anionic polyacrylamide water-in-water emulsion water shutoff profile control agent, and a preparation method and a using method thereof. The anionic polyacrylamide water-in-water emulsion water shutoff profile control agent consists of an anionic polyacrylamide water-in-water emulsion and a cross-linking agent. The preparation method comprises the following steps: adding deionized water, a stabilizing agent, part inorganic salts, nonionic monomers, anionic monomers, a chelating agent and (a chain transfer agent) into a reaction container, stirring uniformly, adjusting the pH value to a suitable range, introducing nitrogen to remove oxygen, adding an initiator to initiate a reaction, adding the remaining part inorganic salts in a reaction process, preserving heat, and discharging materials to obtain the anionic polyacrylamide water-in-water emulsion. The using method of the anionic polyacrylamide water-in-water emulsion serving as a water shutoff profile control agent comprises the following steps: diluting the water-in-water emulsion on situ or on line to prepare a uniform aqueous solution with a certain concentration, adding a certain amount of the cross-linking agent under the condition of stirring, stirring uniformly and injecting the aqueous solution into a stratum to realize the purpose of improving crude oil recovery rate.

A low viscosity wellbore polymer fluid gelling system comprising an aqueous medium and a water-in-water emulsion comprising a plurality of polymers or oligomers, including at least one removable polymer or oligomer, and at least one gelling polymer or oligomer, wherein said fluid has a low viscosity when injected, and the gelling polymer forms a gel downhole which has a storage modulus of at least about 60 Pa after the removable polymer is removed from the fluid. The invention also provides a method of isolating at least one zone of a subterranean formation penetrated by a wellbore, including the steps of preparing a water-in-water emulsion comprising a plurality of polymers or oligomers including at least one removable polymer or oligomer, and at least one gellable polymer or oligomer; combining the water-in-water emulsion with an aqueous medium to prepare a low viscosity polymer fluid; introducing the fluid into a zone in the formation, removing the at least one removable polymer or oligomer, and allowing a remaining gellable oligomer, polymer or polymers to form a gel, isolating the zone from at least one other zone in the formation.

The invention discloses a drag reducer for a slickwater fracturing fluid and a synthesis method for the drag reducer. The synthesis method comprises the following steps: adding 5 to 30 weight percent of an acrylamide monomer A, 5 to 30 weight percent of an anionic monomer B, 50 to 75 weight percent of a dispersion medium C and 0.5 to 5.0 weight percent of a dispersion stabilizer D into a reaction kettle to form a mixture according to preset using amounts, performing uniform stirring, controlling reaction temperature within a range of 40 to 60 DEG C under the protection of nitrogen in the reaction kettle, dropwise adding an initiator E into the mixture, and performing polymerization reaction for 6 to 10 hours to obtain a W/W emulsion drag reducer, with a molecular weight of 4 to 6 millions, for the slickwater fracturing fluid. According to the method, the problems of high difficulty in post-treatment of an organic solvent and pollution caused by high probability of the organic solvent in entering the stratum and groundwater during inverse emulsion polymerization synthesis of a drag reducer, and the problems of smaller molecular weight, large addition, poor drag resistance effects, high post-treatment energy consumption and the like of the drag reducer obtained by solution polymerization are effectively solved; the product is high in water solubility and dissolution speed, and the drag reduction rate is higher than or equal to 70 percent.

The invention discloses a water dispersible profile control agent for oil extraction and a preparation method thereof. The water dispersible profile control agent comprises the following components in parts by weight: 70-150 parts of acrylamide, 5-10 parts of anionic monomer, 5-10 parts of cationic monomer, 1-5 parts of hydrophobic monomer, 15-55 parts of dispersant, 30-85 parts of inorganic salt and 230-500 parts of deionized water. By virtue of water in water dispersion polymerization, the product is instant, so that the liquid preparation time and the curing time of a conventional polyacrylamide solution are shortened. A cationic chain link is introduced based on a conventional gel, so that gel molecules and rocks with negative electricity firmly adsorb so as to increase the flow resistance of water and improve the scouring resistance of the gel. The water dispersible profile control agent is low in initial viscosity, good in pumping property, simple in construction process and small in environmental damage. The water dispersible profile control agent is good in biological stability, and the profile control period of validity is over half a year. The product is obtained by virtue of water in water dispersion polymerization and is instant in the using process.

A stabilizer-free system for transporting active substances in a biological system of one or more active substances and magnetic particles is characterized in that the particles are provided with active substance(s) on at least part of their surface. Modification of the magnetic particles is not absolutely required in this system. It can be incorporated both into aqueous and oily suspensions and into microemulsions, oil-in-water emulsions, water-in-oil emulsions and also water-in-oil-in-water emulsions.

The invention discloses a preparation method of a cationic polyacrylamide water-in-water emulsion. According to the preparation method, a monomer, an inorganic salt C and a dispersing agent D are subjected to addition polymerization reaction under the effect of an initiator I and then prepared into the target product, wherein the dispersing agent is the comb-like graft copolymer which is relatively small in molecular weight, low in positive charge density and high in side chain steric hindrance; the dispersing agent has the advantages of being low in viscosity, fast in dispersing and absorbing speed, stable in dispersing, and good in effect; furthermore, the dispersing agent is given an adjustable molecular structure, so that different structures can be designed for different polymerization systems, the pertinence is high, the viscosity of the polymerization systems can be effectively reduced, the solid content of the product is increased, and the stability of the water-in-water emulsion is improved; and furthermore, the cationic polyacrylamide water-in-water emulsion prepared by the preparation method disclosed by the invention has the advantages of being fast in dissolving speed, high in molecular weight, excellent in liquidity and convenient to use.

The invention relates to a plugging agent for postponing colloid foam and a method thereof for oilfield high-water-content aquifer profile modification water plugging. The plugging agent is composed of a foaming agent system solution and gas, wherein the foaming agent system solution is formed by uniformly dispersing 0.05-0.30% of foaming agent, 0.4-0.6% of water-drum aqueous emulsion polymer and 0.2-0.4% of multiplex emulsion crosslinking agent; and the volume ratio of the foaming agent system solution to the gas under reservoir pressure is 1:(1-3). The plugging agent for postponing colloid foam is used for oilfield high-water-content aquifer profile modification water plugging, and can enhance the oil recovery rate. The invention also provides a method for oilfield high-water-content aquifer profile modification water plugging. The plugging agent has the advantages of high dissolution rate, easy preparation, low initial viscosity and the like, can satisfy on-line injection, enhances the site operability, and saves the construction time and input cost.

Compositions of a water in water emulsion having a first phase of gelled particles with specific aspect ratio and width, are suitable for application in products. Said compositions impart a creamy impression to the final product.