717results about How to "Improve salt resistance" patented technology

The invention discloses a temperature resistant salt tolerant high efficiency gel and a preparation method and application thereof. The preparation method is characterized in that the preparation method comprises the following steps: preparing a comb-shaped associated copolymer PAH containing macromonomers and functional hydrophobic monomers into an aqueous solution having the concentration of 0.1 to 4g/L, the crosslinking agent concentration of 0.01 to 1.0g/L, the surfactant concentration of 0.01 to 8mmol/L and the sodium sulfite thermal stabilizer concentration of 0.005 to 1.0g/L; adding the aqueous solution into a mixing container with a stirring device; stirring the aqueous solution evenly at the room temperature; regulating the pH value of the solution to be equal to between 4 and 11, and obtaining a temperature resistant salt tolerant high efficiency gel polymer solution system used for tertiary oil recovery and scavenge, displacement modification, profile modification or water shutoff. The polymer solution system has micro-crosslinking to form the gel during the flowage inside the oil reservoir. The gel has good elasticity, not easy dehydration, stable gelling performance, and excellent tackification, temperature resistance, salt tolerance, shearing resistance and ageing resistance.

The invention discloses an acrylamide modified graft copolymer and a preparation method and usage thereof. The invention is characterized in that 20 parts of acrylamide, 1-20 anionic monomer and/or cationic monomer, 0.1-15 macromonomer, 0.05-10 ionic lyophobic monomer and 50-1000 deionized water are added into a three-necked reaction bottle, the pH value is adjusted to be 3-9, N2 is introduced for 30min, then 0.002-0.5 part of initiator persulfate is added at 30-75 DEG C, the reaction lasts 8-36h, then copolymer PAB is obtained, and finally water is used for dilution to obtain strong PAB solution. During polymerization, no surfactant is used, and the macromonomer with a long chain and the ionic lyophobic monomer with intermolecular association function are introduced into the copolymer PAB, so the capabilities of cooperative tackification and salt-resistance between the rigid conformation of a molecular chain and the intermolecular association can be played optimally, the PAB exhibits unique solution property and has higher colloidal viscosity in high saline solution than in fresh water, and the PAB obtains the capabilities of tackification, salt resistance, low surface tension and strong molecular association and can be used for the oil-displacing acrylamide modified graft copolymer. The copolymer is prepared into water solution with mass concentration of 0.2-3.0g/L and surfactant concentration of 0.01-2 mmol/L, then the water solution is added into a mixing vessel by a stirring device, and then a polymer oil-displacing agent with tackification, salt resistance and cutting resistance is obtained. The PAB has the functions of both a tackifier and a macromolecule surfactant. The copolymer PAB is prepared into water solution which has mass concentration of 0.05-7%, so the macromolecule surfactant with excellent surface activeness can be obtained and then applicable to an emulsifier, an emulsion splitter, a solubilizer and a wetting agent.

The invention provides association-type non-crosslinking fracturing fluid and a preparation method thereof. The association-type non-crosslinking fracturing fluid is prepared from hydrophobic modified partial hydrolytic polyacrylamide and derivatives of the hydrophobic modified partial hydrolytic polyacrylamide serving as active ingredients, a gel breaker, potassium chloride, an optional surface active agent and water, wherein each of the molecular structures of the hydrophobic modified partial hydrolytic polyacrylamide and the derivatives of the hydrophobic modified partial hydrolytic polyacrylamide contains acrylamide monomer unit, at least one biparental unsaturated monomer unit and at least one an anion alkene unsaturated monomer unit. As the molecular structure of a thickening agent contains a biparental monomer unit, a reversible super-molecule network can be formed in an aqueous solution through intermolecular hydrophobic association, and the high viscosity and the suspending power required by the fracturing fluid can be obtained without needing chemical crosslinking. The association-type non-crosslinking fracturing fluid based on the thickening agent has the characteristics of simple composition, low residue content, low damage, low friction, shear resistance, temperature resistance and salt resistance and can turn into a new generation of fracturing fluid system for replacing guanidine gum and fracturing fluid thereof.

The invention discloses a water soluble copolymer with high viscosity and salt resistance, and a preparation method and an application thereof. The preparation method comprises the steps of: adding acrylamide 20 weight parts, an anionic monomer or/and a cationic monomer 0.1-15 weight parts,, a vinyl polycyclic aromatic hydrocarbon 0.05-4 weight parts,, a surfactant 0.5-90 weight parts,, and deionized water 70-900 weight parts, into a three-neck reaction bottle, adjusting the solution pH to 2.5-9, introducing N2 for 30min, adding an initiator persulfate 0.001-0.2 weight parts, at 20-70DEG C, and reacting for 6-36 hours to obtain a low-molecular weight water soluble copolymer with molecular association ability, high viscosity and salt resistance, which can be used in intermediate-permeability oil reservoir and low-permeability oil reservoir development. An associated water soluble polymer oil displacement agent is obtained by preparing the copolymer into an aqueous solution with copolymer concentration of 0.3-3 g/L and surfactant concentration of 0.01-4 mmol/L, adding into a mixer with a stirring device, and stirring uniformly at room temperature; and the obtained oil displacement agent has high viscosity, salt resistance, temperature resistance and shear resistance, and can be used in intermediate-permeability oil reservoir and the low-permeability oil reservoir development.

The invention discloses a non-linear associated water soluble quadripolymer as well as a preparation method and use thereof, comprising: adding 20 parts of acrylamide, 1-20 parts of nionic monomer or/and cationic monomer, 0.1-15 parts of macromonomer, 0.05-10 parts of hydrophobic monomer, 0.1-50 parts of surfactant and 60-1000 parts of deionized water to a three-necked reaction flask, adjusting the pH to be 3-9, adding 0.002-1 part of initiator (persulphate) at 30-75 DEG C after introducing N2 for 30min, reacting for 8-36h to obtain the quadripolymer PACH, diluting with water, and obtaining concentrated PACH solution. The macromonomer with a long chain and the hydrophobic monomer with a molecular association function are simultaneously introduced in a copolymer PACH, which can obtain the best synergistic viscosifying between rigid conformation of a molecular chain and molecular association and salt resistance. The non-linear associated water soluble quadripolymer is obtained. The copolymer is prepared into aqueous solution with the mass concentration of 0.2-3g/l and the surfactant concentration of 0.01-2mmol/l, added to a mixing vessel with a stirring device and evenly stirred at the room temperature to obtain a viscosified, salt-resistant and shear-resistant polymer oil displacement agent. The PACH has dual functions of a viscosifier and a high molecular surfactant; minute amount of a low molecular surfactant is added to the PACH solution, thus improving the apparent viscosity of the solution, reducing the surface tension of solution and the water-oil interfacial tension, and being beneficial to improving the crude oil recovery ratio. A copolymer PABE is prepared into the aqueous solution with the mass concentration of 0.05-7% to obtain high molecular surfactant with excellent surface activity, and the high molecular surfactant is used as an emulsifier, a demulsifier, a solubilizer and a wetting agent.

The invention belongs to the technical field of development of oil fields, and particularly relates to a seawater-based fracturing fluid which is suitable for preparing sweater and can be used for realizing continuous blending and a preparation method thereof. The seawater-based fracturing fluid is prepared from the following raw materials in part by weight: 0.5-1.5 parts of thickening agent, 0.3-1.0 parts of crosslinking agent, 0.2-0.6 parts of surfactant, 0.01-0.2 parts of pH value regulating agent, 0.01-0.2 parts of viscosity breaker, 46.5-64 parts of seawater and 35-50 parts of desalted seawater. The seawater-based fracturing fluid has the advantages of suitability for preparing seawater, capability of realizing continuous blending, high temperature resistance, high salt resistance, high shear resistance and quick dissolvability.

The invention discloses a fluid loss additive for drilling fluid and a preparation method thereof, belonging to the technical field of chemical drilling fluid treating agents for oilfields. The method comprises the following steps of: carrying out one-step reaction on phenol, formaldehyde, humate, pyrosulfite and anhydrous sulfite so as to obtain a sulfonated phenolic humic acid resin; in the presence of an initiator, carrying out graft copolymerization on the sulfonated phenolic humic acid resin and a mixture of sodium hydroxide, 2-acrylamide-2-methyl-propyl sulfonate, acrylamide and dodecylacrylamide; and carrying out drying and crushing on the obtained product so as to obtain sulfonated phenolic humic acid resin-alkenyl monomer graft copolymer. The fluid loss additive disclosed by the invention has the functions of controlling the rheological property of drilling fluid and reducing the high-temperature and high-pressure filter loss of drilling fluid, not only enhances the thermal stability of side chains of a chain polymer, but also improves the salt tolerance of a sulfonated phenolic resin, and guarantees that products have good properties under high temperature and high salt conditions.

The invention discloses a copolymer with temperature resistance and water solubility and the preparation method and application thereof, which is characterized in that: 20 portions of acrylic amide, 0.1 to 10 portions of anion monomer or/and cation monomer, 0.05 to 3 portions of fluorine-containing styrene or/and perfluoroalkyl styrene hydrophobic monomer, 0.5 to 60 portions of surface active agent and 50 to 700 portions of deionized water are put into a three-necked reaction bulb; after the solution pH is regulated to be equal to 2.5 to 9 and N2 is connected for 30 minutes, 0.001 to 0.2 portion of an evocating agent of persulfate is added under temperature of 20 to 70 DEG C, reacting for 6 to 36 hours, and PATF is prepared. Then water is used for diluting so as to prepare PATF concentrated solution, thus obtaining a copolymer that has medium molecular weight and water solubility, is high-temperature resistant, has an ability of molecular association and can be used in high temperature and high salinity reservoir. The copolymer is prepared into aqueous solution with a mass concentration of 0.3 to 3g/L and a surface-active-agent concentration of 0.01 to 4mmol/L, which is put in a blending container with a dasher and is stirred even at room temperature to prepare a polymer oil-displacing agent which is high-temperature resistant, high tackifying and anti-sharing and has excellent aging resistance under high salinity and the temperature of 110 DEG C. The prepared oil-displacing polymer has excellent solution properties owing to the supermolecular structure formed by the association between molecules of fluorine-containing cinnamene or/and alkylbenzene hydrophobic groups, thus having favorable application prospects in high temperature and high salinity reservoir exploitation.

The invention relates to an oil field fluid loss additive for drilling liquid and its producing method and the application of the treating agent in the process of producing drilling liquid system. The treating agent utilizes the cation monomer dimethyl diallyl ammonium chloride can make the sodium lignin sulfonate and the sulfonated-methyl brown coal graft induced by FeCl3 so as to produce a new fluid loss agent with the resistance to salt and collapse at high temperature. The composed product integrates the brown coal and lignin. The cation introduction improves the resistance to collapse. The weak crosslinking function of the Fe3+ makes the heat resistance improved further based on the brown coal. Therefore, the product can be widely applied in different complicated conditions such as high temperature deep well, gypsum/slat bed, stratum with a bad water sensitivity, fragility stratum and etc. and has a good prospect.

The invention relates to a production method of low-rack coal degradation liquid. Low-rack coal used as a raw material is added with 2-10% of mixed oxidizing agent, 0.1-0.6% of negative catalyst and 0.2-0.5% of stabilizer to oxidize and degrade the low-rank coal, and the mixture is subjected to oxidation reaction, centrifugalization, filtering and vacuum rotating evaporation to obtain colourless low-rack coal degradation liquid. The colourless low-rack coal degradation liquid used as a new product has good effects in promoting growth and development of crops, increasing crop output, improving the crop quality, improving the seed germination rate, improving the plant salt resistance and the like, and is a multi-functional crop conditioner (plant conditioner); the process is simple, energy-saving and environment-friendly, and high in efficiency; one set of equipment can produce the low-rack coal degradation liquid and fulvic acid simultaneously, and the low-rack coal degradation liquid is safe and non-toxic, has strong appetency to plants, can take effect rapidly and is convenient for use.

The invention discloses a high-temperature colloid protecting anticaving fluid loss additive for a drilling fluid. A preparation method of the high-temperature colloid protecting anticaving fluid loss additive comprises the following steps of: dissolving acrylamide and 2-acrylamido-2-methylpropanesulfonic acid into 10-25 percent mixed aqueous solution; adding acrylic acid, fully stirring and dissolving and then adding a potassium hydroxide aqueous solution; adjusting the pH value to be 7-8; introducing nitrogen gas for protecting for 20-30 minutes; heating to be 50-60DEG C; adding dimethyldiallyl-ammonium chloride, ammonium persulfate and thiol and keeping the contant temperature for 2-5 hours to obtain a colloidal product; washing the colloidal product with acetone; removing an unreacted substance, keeping the constant temperature of about 105DEG C and drying for 2-4 hours; and crushing and sieving the crushed substance by a sieve with 60 meshes to obtain a white powdery product, namely the high-temperature colloid protecting anticaving fluid loss additive for the drilling fluid. According to the high-temperature colloid protecting anticaving fluid loss additive, the stability of high-temperature colloid in a waste-based drilling fluid system can be effectively improved.

A water-soluble zwitterionic copolymer contains two structure units: 2-methyl-2- acrylamido propanesulfonic acid and methyl acrylyloxyethyl trimethyl ammonium chloride. Its preparing process includes such steps as proportionally adding the anhydrate sorbitol monooleate and the anhydrated sorbitol monostearate to kerosene, proportionally dissolving two monomers in water and regulating its pH=7, proportionally mixing oil phase with water phase, filling N2, adding redox trigger, and redox reaction in constant-temp water bath.

The invention provides a temperature-resistant and salt-resistant polymer clean fracturing fluid thickening agent and a preparation method thereof. The temperature-resistant and salt-resistant polymer clean fracturing fluid thickening agent has the advantages of cleanliness, low damage, environmentally friendly characteristics, good viscosity increasing effects, very strong suspension properties,good thermal adaptability allowing a super-wide temperature range of 25 to 240 DEG C, good salt resistance, excellent shear stability, small frictional resistance, obvious fracture effects, long lasting time spent on production after compression, and good cost performance.

This invention relates to a preparation method for poly-asparagic acid resin, which takes poly-pyrrolidine dione as the raw material to make crosslink poly-pyrrolidine dione with method of non-even phase suspended emulsion crosslink or non-even phase suspension crosslink and processes poly-asparagic acid resin by hydrolyzation characterizing that the crosslink poly-pyrrolidine dione is prepared by multi-section crosslink reaction, in which, the crosslinker is fed in for 2-4 times in equal volume and equal time interval, the crosslink poly-pyrrolidine dione and the resin are aged and crystallized and quickly dried, A ageing and crystallization process for 1-10 days under room temperature, B, quick drying process is carried out under -54-40deg.C.

The invention discloses a preparation method of an organic and inorganic composite flushing liquid, and belongs to the technique of oil well cement well cementation. The flushing liquid comprises the following components: polysorbate-80, alkyl phenol polyethylene glycol ether, dodecyl benzene sulfonic acid sodium, sodium silicate, sodium pyrophosphate and water, wherein the mass ratio of each component is as follows: 20%-30% of polysorbate-80, 10%-15% of alkyl phenol polyethylene glycol ether, 5%-10% of dodecyl benzene sulfonic acid sodium, 10%-20% of sodium silicate, 5%-10% of sodium pyrophosphate and the balance of water. The flushing liquid is suitable for both the oil-based mud and water-based mud, has high flushing efficiency, improves the replacement efficiency of a well drilling liquid and cement sheath interfacial cementation quality, and can be used under the condition of 50 DEG C-200 DEG C.

The invention discloses a method for preparing a high-stability heat-resistance and salt-tolerance air foam oil displacing agent. According to the method, a nanometer and nanometer modification technology is adopted, and nanometer hectorite is used as a foam stabilizer and a high-temperature stabilizer to prepare the high-stability heat-resistance and salt-tolerance air foam oil displacing agent. The technology includes the following steps that the hectorite is added into deionized water at the temperature of 50-90 DEG C, stirred and dispersed evenly, cooled to the room temperature and stewed and aged for a period of time to obtain hectorite aqueous dispersion, quantitative cationic surface active agents are added, evenly stirred, stewed and aged, finally, foaming agents are added, high-speed stirring is conducted on a high-speed emulsification machine, and the high-stability heat-resistance and salt-tolerance air foam oil displacing agent is obtained. The foam half-life period reaches up to 768 hours, the high foam stability is achieved, the foam half-life period reaches up to 70 hours under the condition that the degree of mineralization is 30000 mg/L, the good salt tolerance is achieved, the apparent viscosity reaches up to 2000 mPa.s, the heat resistance performance reaches 90 DEG C, the high foam strength and the heat resistance are achieved, the shearing rate is 170 per second, the foam apparent viscosity reaches 800 mPa.s after shearing is conducted for 60 minutes, the good shearing performance is achieved, and the method is suitable for exploration and development of conventional and unconventional oil fields.

The invention discloses a high-temperature-resistance low-friction weighted clean fracturing fluid which is suitable for high-temperature and high-pressure reservoir reconstruction at 170 DEG C and a preparation method thereof.The fracturing fluid is prepared from, by weight, 0.2%-0.8% of high-temperature-resistance thickening agent, 0.1%-0.8% of system synergist, 0.1%-0.3% of high temperature stabilizer, 0%-42% of weighting agent and the balance fresh water.The high-temperature-resistance low-friction weighted clean fracturing fluid has the following functions and advantages that the weighting agent can be adopted for weighting, and the density is adjustable between 0 and 1.32 g/cm<3>; good temperature-resistance and anti-shearing properties are achieved, and the requirement of high-temperature deep well fracturing construction at 170 DEG C can be met by adjusting a formula; a good resistance reduction property is achieved, pipeline friction resistance can be effectively reduced, and the resistance reduction rate can reach 70%; the fracturing fluid is a fluid with a reversible structure, and the structure damage after high shearing is small; the residue content of the fracturing fluid is decreased to below 10 mg/L, damage to a reservoir and supporting cracks is reduced, the fracturing effect is improved, and the reservoir productivity is increased.

The invention discloses a profile-control and water-plugging agent and a profile-control and water-plugging method used for profile control and water plugging of high-temperature and high-salinity oil reservoir. The profile-control and water-plugging agent comprises the following raw materials, by weight, 0.3-0.6% of hydrolyzed polyacrylamide, 0.1-0.2% of a crosslinking agent, 0.1-0.2% of a stabilizer, 3.2-4.0% of an inorganic particle inducer, and 95-96.3% of water containing calcium ion. In the raw materials of the profile-control and water-plugging agent, the hydrolyzed polyacrylamide can be subjected to a crosslinking reaction under the effects of the crosslinking agent and the stabilizer to form a polymer gel which has excellent anti-salt performance; the inorganic particle inducer and the calcium ion are reacted to each other to form inorganic particles which have high temperature resistance. The profile-control and water-plugging agent composed of the polymer gel and the inorganic particles belongs to an inorganic/organic composite gel and has high plugging strength and long-period stability under a high-temperature and high-salinity condition.

The invention relates to high-temperature-resistant high-density formate polysulfonate drilling fluid and a preparation method thereof. The high-temperature-resistant high-density formate polysulfonate drilling fluid comprises, by weight, 100 parts of water, 2-5 parts of bentonite, 0.1-10 parts of high-temperature-resistant sulphate polymer, 20-100 parts of formate, 0.6-2.0 parts of potassium hydroxide, 8-20 parts of sulfonating agent, 2-6 parts of blocking agent, 0.5-3.0 parts of emulsifier, 0.2-3.0 parts of pH regulator, and 120-270 parts of barite powder. The invention further provides the preparation method of the high-temperature-resistant high-density formate polysulfonate drilling fluid. The high-temperature-resistant high-density formate polysulfonate drilling fluid is applicable to petroleum drilling of deep wells and extra-deep wells, especially wells in high-thickness salt bed, is capable of resisting the temperature up to 180 DEG C under the density of 1.8-2.5g/cm<3>, tolerating salt to saturation and resisting calcium at 800-1000ppm, and is drilling fluid which is fine in performance and resistant to high temperature, high pressure and hypersalinity.

The invention discloses a liquid thickening agent system including an organic solvent, a plant gum thickener, an organic thickener, an emulsifier and water. According to the thickening agent system disclosed by the invention, the thickening agent system is easy to prepare and has a certain salt resistance; the thickening agent system is fast to swell when used for being mixed with water to prepare a fracturing fluid, the requirement on preparing water is low, and even if sea water (containing salt) is used, the swelling effect of the thickening agent is also not affected.