248 results about "Polymer flood" patented technology

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 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 a flooding system used for improving the recovery factor after polymer flooding and a preparation method thereof, which belongs to the technical field of enhanced recovery of oil fields. A surfactant with unlike charges and a polymer react with each other to produce a high-activity compound; and the high-activity compound is mixed with a non-ionic surfactant to produce the novel flooding system. The novel flooding system solves the problems of the poor temperature resistance and the inorganic high valence cation resistance of the prior flooding system. The novel flooding system has the advantages of high viscocity, ultra-low interfacial tension, low feeding quantity and so on. The system has wide application prospects in oil fields to apply the technology for improving the oil recovery factor.

The invention relates to a novel polymeric oil-displacing agent for improving recovery ratio and application thereof. The polymeric oil-displacing agent is a novel association polymer which has different hydrophobic monomers in different contents and is synthesized through free radical polymerization method by taking acrylic amide (AM)-acrylic acid (AA)-hydrophobic monomers as the reactant monomers, wherein the hydrophobic monomers include dimethyl-allyl-p-alkyl-benzyl ammonium chloride. The polymeric oil-displacing agent presents high viscidity under high temperature and high hypersalinity, so the polymeric oil-displacing agent is suitable for high-temperature and high-hypersalinity oil deposits. The polymeric oil-displacing agent has good temperature tolerance, salt tolerance and resistance to shear, and good injectivity and transmissibility as well as the abilities to build up good resistance coefficient and residual resistance coefficient, and can effectively improve the recovery ratio of crude oil. The oil-displacing agent is widely applicable in tertiary oil extraction field and has good market prospect.

The present disclosure relates to enhanced oil recovery methods including the injection of solvent and polymer floods to increase hydrocarbon production from oil bearing underground rock formations. One method includes injecting a solvent slug into the underground formation for a first time period from a first well. The solvent slug solubilizes the oil and generates a mixture of mobilized oil and solvent. An aqueous polymer slug may then be injected into the underground formation for a second time from the first well. The polymer slug may have a viscosity greater than the solvent slug and thereby generates an interface between the solvent slug and the polymer slug. The solvent slug and the mobilized oil are then forced towards a second well using a buoyant hydrodynamic force generated by the aqueous polymer slug. Oil and / or gas may then be produced from the second well.

The invention discloses a Brevibacillus borstelensis Po CGMCC No. of 2441 and the application thereof. A microbial inoculum that contains the brevibacillus borstelensis Po CGMCC No. of 2441 also belongs to the extent of protection of the invention. Model oil displacing experiment results indicate that after the oil displacement with polymers, the brevibacillus borstelensis oil displacement can be used for raising the recovery factor by 3 to 5 percent (OOIP), the brevibacillus borstelensis oil displacement combined with a polymer protecting slug can be used for raising the recovery factor by about 7 percent (OOIP), and a brevibacillus borstelensis oil displacing method that is combined with chemical oil displacement can be used for raising the recovery factor by 6 to 13 percent (OOIP). The experiment results indicate that the strain can be widely applied into the field of oil exploiting industries and particularly into the field of enhanced microorganism oil exploiting, and is applicable to large-area popularization and application.

The invention relates to a hydrophobically associating water-soluble polymer (HAWSP) oil displacement agent and a preparation method thereof. The technical scheme is that: the HAWSP oil displacement agent comprises the following monomers and monomers in percentage by mass: 53.5 to 59.9 percent of acrylamide (AM), 40 to 45 percent of sodium acrylate (NaAA) and 0.1 to 1.5 percent of N-allyl oleylamine (NAO); and the preparation method comprises the following steps of: adding the NAO into a reactor; adding OP-10 and water; adding the AM, AA and NaOH after emulsification is performed completely to prepare a solution with the monomer total mass percentage concentration of 10 to 25 percent; adjusting the pH value to 7.5 to 11; introducing N2 for 20 minutes; adding an initiator; continuously introducing N2 for 20 minutes; reacting at the temperature of between 30 and 70 DEG C for 4 to 12 hours; washing by using absolute ethanol; and crushing and drying to prepare AM / NaAA / NAO terpolymer. The polymer has water solubility and high temperature tolerance, salt tolerance and shearing resistance, and can increase a crude oil recovery rate by over 10 percent simulatively.

The invention relates to a composite oil flooding experimental method of alternately injecting gel and a polymer solution after water flooding and polymer flooding. The method specifically includes the following steps of firstly, manufacturing large flat plate cores, and marking the large flat plate cores as the first large flat plate core and the second large flat plate core; secondly, conducting water flooding, and calculating the water flooding recovery ratio; thirdly, conducting polymer flooding, and calculating the polymer flooding limited recovery ratio; fourthly, alternately injecting the gel and the polymer solution to conduct oil flooding; fifthly, conducting subsequent water flooding, and calculating the final recovery ratio. The method has the technical advantages that the gel has the gradually-gluing characteristic, temporary blocking is conducted on a high-permeability layer, and the swept volume is expanded through fluid which subsequently flows in; the instant negative pressure can be formed through the viscosity of the gel, and therefore the recovery ratio is greatly increased on the basis of polymer flooding; due to the fact that the price of the polymer is relatively low, the gel and polymer alternate injection technology is simple, and the method has the great application prospects on site.

The invention relates to a temperature and salt resistant hydrophobic association polymer oil displacement agent and its preparation method. The preparation scheme of the oil displacement agent is characterized in that the oil displacement agent comprises 57.0-59.8% (g / g) of acrylamide (AM), 39.3-40.0% (g / g) of sodium acrylate (NaAA), 0.1-0.2% (g / g) of N-allylphenylacetamide (NAPA), and 0.1-3.5% (g / g) of N,N-dimethyl-N-allylhexadecyl ammonium chloride (AHAC); and the preparation method comprises the following steps: adding the NAPA, the AHAC and an emulsifier into a reactor, adding water, and completely emulsifying; adding the NaAA and the AM, adjusting the pH value to 7, adding an initiator, reacting, washing, crushing, and drying to obtain a polymer product. The polymer has the characteristics of water solubility, high tackifying capability and high water and shear resistances. The viscosity reservation rate of the polymer solution having a concentration of 0.1wt% at 100DEG C reaches 91.3%, and the polymer can improve the simulation crude oil recovery efficiency by 16.6%.

This invention relates to enhanced oil recovery methods to improve hydrocarbon reservoir production. An enhanced oil recovery screening model has been developed which consists of a set of correlations to estimate the oil recovery from miscible and immiscible gas / solvent injection (CO2, N2, and hydrocarbons), polymer flood, surfactant polymer flood, alkaline-polymer flood and alkaline surfactant-polymer flood.

The invention relates to an oil-displacement agent used in an oil field for improving the recovery efficiency, and a synthesizing method thereof. The synthesizing method comprises the technical schemes that: the agent is prepared from raw materials and monomers of, by mass: 53.5-59.5% of acrylamide AM, 40-45% of sodium acrylate NaAA, and 0.5-1.5% of N-allylcaprolactam NAC; 0.153g of NAC is first added into a flask; 8.53g of AM, 4.23g of AA, and 2.4g of NaOH are added into the flask, such that an aqueous solution with a monomer mass percentage concentration of 10-20%; nitrogen is delivered into the mixture for 20min; (NH4)2S2O8 and NaHSO3 solutions are added; nitrogen is then delivered in for 10-20min; the mixture is subject to a reaction for 4-12h under a temperature of 30-70 DEG C; the product is washed by using absolute ethanol, and is crushed and dried, such that the AM / NaAA / NAC ternary polymer is obtained. The polymer provided by the invention is water-soluble, and shows good temperature resistance, salt resistance, and shearing resistance. As a result of indoor simulation, crude oil recovery efficiency can be improved by 10%.

The invention relates to an AM(acrylamide) / AA(acrylic acid) / NVP(N-vinyl pyrrolidinone) / YEML quadripolymer oil-displacing agent and a synthetic method thereof. According to the quadripolymer oil-displacing agent, the oil recovery can be enhanced by polymer flooding. According to the technical scheme, the oil-displacing agent is a quadripolymer consisting of AM, AA, (NVP), a functional monomer (YEML) prepared from ethanediamine and maleic anhydride; the oil-displacing agent is prepared from the following raw materials: 63.5%-70% of AM, 28.7%-36% of AA, 0.1%-0.2% of NVP and 0.1%-0.2% of YEML. The synthetic method comprises the following steps: adding the prepared YEML monomer into a flask firstly; then adding the AM, NVP, acrylic acid and NaOH to prepare a solution with total monomer mass concentration of 10-20%; introducing nitrogen for 30 minutes, then adding an initiator; continuing to introduce N2 for 10-20 minutes, and reacting for 4-12 hours at 30-60 DEG C; washing with absolute ethyl alcohol, crushing, and drying to prepare the AM / AA / NVP / YEML quadripolymer. The viscosity, temperature resistance and salt tolerance and shearing resistance of the quadripolymer are improved greatly, the oil recovery can be better enhanced, and the quadripolymer can be used for oil extraction in an oil field.

The invention provides a cleaning method of an ultra-filtration membrane used in membrane-process polymer-flooding oilfield wastewater treatment. The cleaning method comprises the steps of (1) physical cleaning and chemical cleaning, wherein chemical cleaning comprises the following steps: (2) cleaning with a pickling solution; (3) cleaning with a sodium hydrogenfluoride and alkaline mixed solution, a sodium hydrogenfluoride and acid mixed solution or a sodium hydrogenfluoride and sodium fluoride mixed solution; (4) cleaning with an oxidizing agent lotion; (5) cleaning with a membrane cleaning additive; (6) cleaning with a surfactant or an organic solvent cleaning agent.

The invention relates to an alkyl betaine surfactant composition for tertiary oil recovery, and a preparation method thereof. The problems of bad oil displacement efficiency, high use concentration, and corrosion and incrustation damages of alkalis in alkaline-surfactant-polymer flooding to stratums and oil wells of an oil displacement composition containing routine surfactants in high-temperature and high-salinity oil reservoirs, especially stratum water containing HCO3<-> in the prior art are mainly solved. The oil displacement composition for tertiary oil recovery comprises 1 part by weight of a betaine surfactant and 0.01-10 parts by weight of a polymer, wherein the molecular general formula of the betaine surfactant is shown in the specification; in the formula, R is a C8-C30 alkyl group, R' is a C1-C6 alkylidene group, and a value of n+m is 2-100; and the polymer is one selected from ultrahigh molecular weight polyacrylamide, a temperature and salt resistant polymer A and xanthan gum. The composition well solves the problems, and can be used in the tertiary oil recovery of oilfields.

The invention provides a functional polymer with surface activity as well as a preparation method and application thereof. The functional polymer with surface activity contains a structural unit A, a structural unit B and a structural unit C, wherein the structural unit A has a structure as shown in a formula (1) in the specification; the structural unit B has a structure as shown in a formula (2) in the specification; the structural unit C has a structure as shown in a formula (3) in the specification; based on the weight of the polymer, the content of the structural unit A is 50-88wt%; the content of the structural unit B is 10-40wt%; the content of the structural unit C is 2-10wt%; the viscosity-average molecular weight of the polymer is 6-12 million. The functional polymer with surface activity has good temperature and salt resistance and a capability of thickening water media. The polymer oil displacement agent is applicable to oil reservoirs with low to medium permeability and high-temperature and high-salinity oil reservoirs and can conduce to further enhancing the oil recovery in tertiary oil recovery.

The invention discloses water-solubility micro-crosslinking copolymer, a method for making the same and an application of the same. The method is characterized in that: 20 portions of acrylamide, 0.5 to 15 portions of anion monomer, 0.1 to 6 portions of divinyl benzene, 0.5 to 50 portions of sodium laurylsulfate and 50 to 800 portions of deionized water are added in a three-necked reaction bottle, and the pH value of the solution is adjusted to between 4 and 9; after N2 is injected for 30 minutes, 0.001 to 0.2 portions of initiator persulphate is added in at a temperature of between 30 and 70 DEG C so as to carry out reaction for 6 to 36 hours, thereby obtaining PADM; then, the PADM is diluted by water to obtain a PADM solution, thereby obtaining the water-solubility micro-crosslinking copolymer which has ideal water solubility, copolymerization micro-crosslinking structure, difficult intramolecular crimp and molecular association capacity and can be used in oil expulsion. The copolymer is made into an aqueous solution with the mass concentration of between 0.3 and 3 g / L and the surfactant concentration of between 0.01 and 4 mmol / L, and then is added in a mixing vessel provided with a stirring device so as to be stirred evenly at room temperature, thereby obtaining a polymer oil displacement agent which is tackifying, salt resistant, thermotolerant and shear resistant and has excellent age resistance under the conditions of high salt and 110 DEG C. Moreover, the raw materials of PADM are easy to obtain; therefore, the water-solubility micro-crosslinking copolymer and the method have enormous application prospect in increasing crude oil recovery ratio.

The invention discloses Bacillus licheniformis U1-3CGMCC No.2437 and application thereof. The microbial inoculum which contains the Bacillus licheniformis U1-3CGMCC No.2437 is also protected by the invention. Model oil displacement test results show that the Bacillus licheniformis after polymer flooding for oil displacement can improve the recovery ratio by 3 to 5 percent (OOIP), the Bacillus licheniformis after polymer flooding for polymer protecting plug oil displacement can improve the recovery ratio by about 7 percent (OOIP), and the Bacillus licheniformis after polymer flooding for oil displacement combined with the chemical flooding can improve the recovery ratio by 6 to 13 percent (OOIP). The test results prove that the Bacillus licheniformis U1-3CGMCC No.2437 can be widely applied in the oil production engineering field, in particular the microorganism intensified oil production field, and is suitable for wide promotion and application.

The invention discloses a dendritic polymer, dendritic polymer monomer, and preparation methods and application of the two. The dendritic polymer monomer has the structure of Z'-(Q)n-Y, wherein the Z' has the structure shown as a formula (a) and / or a formula (b), Q represents the dendritic repeated structure unit of the dendritric polymer monomer, n represents the generation quantity of the dendritric polymer monomer and is an integer of 2-6, Y represents a group containing SO3- and COO-, and R2-R4 are same or different and independently represent H or an alkyl with the carbon atom number of 1-5. The monomer can be used as a copolymerization monomer for preparing a hyperbranched polymer for oil fields, the obtained hyperbranched polymer can be used as a drilling-fluid inhibitive filtrate reducer, a flocculating agent, an encapsulating agent, a temperature-resistant salt-resistant polymer oil displacement agent, a fracturing-fluid thickening agent and the like, and the monomer also can be used to prepare other-purpose water-soluble polymers and inner surfactant for emulsion polymerization.

The invention provides a hyperbranched polymer oil-displacing agent and a preparation method thereof. The hyperbranched polymer oil-displacing agent is formed by a spherical parent nucleus and a polyacrylamide chain segment, a sodium polyacrylate chain segment and a poly amphoteric multi-claw dewatering functional chain segment which are connected in sequence, wherein, one end of the polyacrylamide chain segment is connected to the spherical parent nucleus, and the other end of the polyacrylamide chain segment is connected to the sodium polyacrylate chain segment. The poly amphoteric multi-claw dewatering functional chain segment is formed by polymerization of acrylic betaine monomer or acrylic bromine quaternary ammonium salt monomer. The viscosity average molecular weight of the hyperbranched polymer oil-displacing agent is 3.5 to 10 millions, and mass ratio of the spherical parent nucleus to the polyacrylamide chain segment to the sodium polyacrylate chain segment to the poly amphoteric multi-claw dewatering functional chain segment is 1:200-350:60-85:6-14 in sequence. The hyperbranched polymer oil-displacing agent is obtained by polymerization of a water phase radical solution, and a preparation process has mild conditions, simple steps, environment friendliness without pollutant and can obtain products of a series of molecular weights. The obtained hyperbranched polymer oil-displacing agent has higher anti-shear capability, higher tackifying capability, well solubility and anti-salt capability and has an oil gas field application prospect.

The invention belongs to the technical field of nanometer materials, and mainly relates to a preparation method and application of a hydrophilic magnetic nanometer material. The preparation method andapplication of the hydrophilic magnetic nanometer material comprise preparation of a ferroferric oxide nanometer fluid, synthesis of polyethylene glycol (PEG) modified gamma-(2,3-epoxypropoxy)propyltrimethoxysilane (KH560), modification of the PEG-modified silane on the surface of the ferroferric oxide nanoparticles and application examples. The preparation process is simple, the production costis low, no by-products are produced, and the prepared nanoparticles are about 16 nm, and have the advantages of uniform particle size, good magnetic response, good hydrophilicity, non-toxicity and environmental friendliness. The nanofluid obtained through uniform dispersion of the nanoparticles can significantly reduce oil-water interfacial tension, and can improve solid mineral surface wettability, indicating a good application prospect of the nanofluid in the fields of oil-solid separation, tertiary oil recovery, drug carrier, polymer flooding, etc.

The invention relates to a fluorescent monomer, a fluorescent tracing polymer and its preparation method. Its synthetic method comprises the following steps of: dissolving 7-diethylamino-4-methylcoumarin in a solvent, adding dropwisely bromopropylene, heating, cooling to obtain the fluorescent monomer allyl-7-diethylamino-4-methylcoumarin-ammonium bromide, and copolymerizing the fluorescent monomer with acrylamide and acrylic acid. The fluorescent polymer can be used as an oil field tracer to be applied in oilfield water-flooding and polymer flooding processes, and has good fluorescent tracer ability and chemical stability.

A low-temperature demulsifier for dehydration of produced liquid by polymer flooding in the oil field is characterized in that the demulsifier comprises the following components according to the weight percentage: 15.0-25% of demulsifier SAP 1187; 17-25% of demulsifier PFA311; 12-16% of demulsifier 101; 0.04-0.1% of alkyl amidopropyl betaine; 0.05-0.08% of iron dichloride; 0.06-0.09% of Vitamin C; 0.08-0.15% of fluorocarbon surfactant FN-3 and the balance of water. The invention has the following effects: when the temperature of produced liquid by polymer flooding is 40 DEG C and the dosage is 50-70mg / l, the water content of the dehydrated crude oil is less than 0.2% and the oil content of the separated sewage is less than 500mg / l.

The invention relates to a preparation method of ultra high molecular weight anionic polyacrylamide, especially to a preparation method of acrylamide homopolymers. The invention belongs to a macromolecular compound obtained only by a carbon-carbon unsaturated bond reaction. The preparation method is characterized by comprising the following steps of: a, using the same kind of water-soluble azo initiator; b, pouring raw materials of an acrylamide monomer aqueous solution, a hydrolytic agent, an additional auxiliary agent and the initiator at a time; c, initiating at low temperature, performing adiabatic polymerization, hydrolyzing, granulating, drying and crushing; and d, preparing the ultra high molecular weight anionic polyacrylamide product with its molecular weight being greater than or equal to 30 million. The preparation method of the ultra high molecular weight anionic polyacrylamide has advantages of single initiator component, simple operation technology and high molecular weight of the product (greater than or equal to 30 million). The prepared product is suitable for polymer flooding of tertiary oil recovery in the oil field, flocculating agent for sewage treatment and papermaking, weaving, printing and dyeing industries.

The invention relates to a method for obtaining well test interpretation parameters of a polymer flooding three-layer channeling reservoir. The method for obtaining the well test interpretation parameter of a polymer flooding three-layer channeling reservoir comprises the following steps that (1) according to rheological properties of a polymer solution, modifier formulas of a polymer solution viscosity model are determined, and according to characteristics of the polymer flooding three-layer channeling reservoir, a physical model of the polymer flooding three-layer channeling reservoir is established; (2) according to the modifier formulas of the polymer solution viscosity model and the physical model of the polymer flooding three-layer channeling reservoir, a mathematical model of the polymer flooding three layers channeling reservoir is determined; (3) the mathematical model of the polymer flooding three-layer channeling reservoir is solved through a finite difference method, and the numerical solution of the bottom hole pressure is obtained; (4) wellbore storage coefficients, formation coefficients, storage capacity ratios, time and the bottom hole pressure are nondimensionalized, and typical curve theoretical map of the polymer flooding three-layer channeling reservoir is drawn; and (5) the reservoir permeability, the skin factor and the wellbore reservoir coefficients of the polymer flooding three-layer channeling reservoir are obtained by fitting the typical curve theoretical map of the three-layer polymer flooding reservoir with measured data curves of oilfields.

The invention relates to a numerical simulation method for performing oil displacing after polymer flooding by alternatively injecting gel and chemical agent through CMG software. The method comprises the following steps of step one, determining a simulation block; step two, designing a numerical simulation prediction scheme; step three, obtaining results of the numerical simulation prediction scheme and analyzing. According to the method, the CMG numerical simulation software is used, by fitting the displacement process of alternatively injecting the gel and the chemical agent in a test block, and the oil displacing effect of alternatively injecting the gel and the chemical agent in a slug mode after polymer flooding is simulated; influences of different gel slugs, different chemical agent slugs, alternative injecting modes and alternative injecting rounds on recovery efficiency are studied to seek a good method for further extracting remaining oil after polymer flooding and improving the recovery efficiency of crude oil, and certain technical reference is provided for further exploitation of a polymer flooding oil field.

The invention discloses an efficient emulsion breaker containing polymer for processing crude oil and a preparation method thereof. Phenol-amine resin is used as an initiator, block polymerization is conducted between the phenol-amine resin and epoxybutane, epoxypropane and ethylene oxide under the action of a potassium hydroxide catalyst, and thus the efficient emulsion breaker containing the polymer for processing crude oil is obtained. The preparation method comprises the steps of synthesis of the phenol-amine resin for the initiator, synthesis of the phenol-amine resin initiator and synthesis of the efficient emulsion breaker containing the polymer for processing crude oil. The prepared emulsion breaker can increase the demulsification dehydration rate of crude oil emulsion driven by polymer and has great practical significance in production of oil fields.

The invention relates to the oil field oil extraction field and particularly relates to a low-concentration and efficient composite oil displacement composition. The composition contains the followingcomponents: sodium lauryl sulfate, N-dodecyl N methylpyrrolidinium bromide and partially hydrolyzed polyacrylamide. The composition contains simple components, and a surfactant oil replacement groupis formed by an anionic surfactant, a cationic surfactant or an additional nonionic surfactant and a cosurfactant, so that the taboo that the anionic surfactant and the cationic surfactant are hardlysimultaneously used is broken through; and the surfactant oil replacement group is further combined with oil replacement components of the composition, and the advantages of surfactant oil replacementand polymer oil replacement are adequately utilized, so that the oil extraction efficiency is comprehensively improved. Compared with common oil displacement composition products, the low-concentration and efficient composite oil displacement composition has the advantages that the use amount is fewer when an oil replacement solution is formed, the oil extraction can be remarkably lowered, the huge economic benefit can be created, and the composition has a potential market value.

The invention relates to a water-soluble tracing polymer oil displacement agent for increasing the crude oil recovery rate in oil fields and a preparation method thereof. In the technical scheme, the used materials and the weight percentage of each monomer are as follows: 70 to 79.9 percent of acrylamide AM, 20 to 28 percent of sodium acrylate NaAA and 0.1 to 2 percent of allyl-7-hydroxy-4-methylcoumarin AMCO; and the preparation method for the water-soluble tracing polymer oil displacement agent includes the following steps: the AMCO, OP-10 emulsifier and water are added into a reaction bottle, the AM, crylic acid and NaOH are added after emulsification, so that aqueous solution with 15 to 25 percent of monomer concentration is prepared, pH is regulated to 7 to 11, and N2 is filled for 20 minutes; initiator is then added, N2 continues to be filled for 20 minutes, and reaction is carried out under 30 DEG C to 70 DEG C for 4 to 12 hours; and finally, after absolute ethyl alcohol washing, grinding and drying, AM / NaAA / AMCO polymer is prepared. The product is water-soluble and fluorescent, and shows good temperature tolerance, salt tolerance and shear resistance, and the result of an indoor simulated oil displacement experiment indicates that the polymer can effectively increase the crude oil recovery rate.

The invention provides a betaine type amphiphilic polymer supramolecular oil displacement system which is prepared from the following components in mass percent: 0.05-1.50% of betaine type amphiphilicpolymer, 0.01-0.15% of organic polyprotic acid and 99.94-98.40% of mineralized water. The betaine type amphiphilic polymer supramolecular oil displacement system can effectively improve the viscosityof the amphiphilic polymer oil displacement system, reduce the dosage of the polymer, effectively reduce the water-oil mobility ratio as well as increase the swept volume and the oil displacement efficiency of the polymer under the conditions of high temperature, high salt content and oil deposition, and has good application prospects and economic values in the field of tertiary oil recovery of an oil field. The system provided by the invention is simple in construction step, convenient in operation and high in practicability.

Belonging to the technologies of oil reservoir reserve and yield increase and oil recovery improvement, the invention provides a preparation method of a nano-oil recovery displacement agent NDA for construction of nano-apertures. The nano-oil displacement agent is characterized in that: the nano-oil displacement agent is prepared according to the underground rock components, oil-water components, permeability contrast, stratum temperature and pressure, and is used for dissolving polymer and removing polymer flooding formed blocking; air foams reduce the flow rate of mid-high permeability apertures to displace remaining oil; an imbibition agent enters nano-apertures rapidly; the solvent dissolving rocks and stratum generated latent acid construct and enlarge nano-apertures and micrometer apertures in dense base rock to enhance the adsorbed oil desorption speed; a neutral wetting agent enables the adsorbed oil to break away from the rock wall surface so as to form oil flow; through combined action, the diffusion speed and seepage velocity are enhanced, and the reserve and yield are increased. The nano-oil displacement agent can displace mid-high permeability, dense low permeation remaining oil, and also can output the adsorbed oil in base rock nano-apertures.