阅读说明：本技术 聚合物微球乳液及其制备方法和应用 (Polymer microsphere emulsion and preparation method and application thereof ) 是由 许汇 苏智青 夏燕敏 王兰 朱益兴 于 2019-10-24 设计创作，主要内容包括：本发明提供了一种聚合物微球乳液,包括聚合物微球、油溶性溶剂和水,其中所述聚合物微球含有荧光性结构单元。本发明提供的聚合物微球乳液的制备方法操作简单方便,并且采用不同粒径微球乳液复配,可以达到深度调剖的同时对注入液流度示踪的目的。(The invention provides a polymer microsphere emulsion which comprises polymer microspheres, an oil-soluble solvent and water, wherein the polymer microspheres contain fluorescent structural units. The preparation method of the polymer microsphere emulsion provided by the invention is simple and convenient to operate, and the microsphere emulsions with different particle sizes are compounded, so that the purposes of deep profile control and injection liquid fluidity tracing can be achieved.)

1. A polymer microsphere emulsion comprises polymer microspheres, an oil-soluble solvent and water, wherein the polymer microspheres contain fluorescent structural units.

2. The polymer microsphere emulsion according to claim 1, wherein the fluorescent structural unit is derived from a functional monomer having a fluorescent structure, preferably at least one selected from the group consisting of 4, 4-dihydroxytetraphenylethylene, vinylcarbazole, 1, 8-naphthalimide, potassium 2-allyloxynaphthalene-6, 8-disulfonate, styryl fluorescein derivatives and styryl coumarin derivatives, and/or the oil-soluble solvent is selected from at least one selected from the group consisting of petroleum fractions, carboxylic acid esters, diesters and vegetable oils, preferably the petroleum fractions are white oils and/or mineral spirits.

3. The polymeric microsphere emulsion according to claim 1 or 2, comprising in parts by weight: 15-35 parts of polymer microspheres, 10-60 parts of oil-soluble solvent and 25-55 parts of water, wherein the water is preferably deionized water.

4. The polymer microsphere emulsion according to any one of claims 1 to3, wherein the polymer microspheres are polymerized from a nonionic monomer, an anionic monomer, a cationic monomer and a functional monomer with a fluorescent structure under the action of a crosslinking agent; and/or

The initial particle size of the polymer microsphere is in the range of 100nm-2 mu m.

5. A method of preparing a polymeric microsphere emulsion comprising:

step A: mixing a nonionic monomer, an anionic monomer, a functional monomer with a fluorescent structure, a first initiator, a cross-linking agent and an optional cationic monomer with water to obtain a water phase;

and B: mixing an emulsifier and an oil-soluble solvent to obtain an oil phase;

and C: mixing the water phase with the oil phase, and emulsifying to obtain an inverse emulsion;

step D: and mixing the inverse emulsion with a second initiator to carry out polymerization reaction to obtain the polymer microsphere emulsion.

6. The process according to claim 5, wherein in step A, the total monomer concentration of the aqueous phase is 40% to 60%, and/or

In the step C, the emulsifying time is 3-10min, preferably 4-8 min; and/or

In the step D, during the polymerization reaction, the temperature of the reaction liquid is monitored, the reaction starting temperature is 8-20 ℃, more preferably 8-12 ℃, the temperature rising speed is controlled to be 1-2 ℃/min, the temperature rising process of the reaction is controlled within 1 hour, and the temperature is kept for 0.5-1.5 hours after the temperature does not rise any more.

7. The production method according to claim 5 or 6, wherein the nonionic monomer is 5 to 99.8 parts by weight, the anionic monomer is 0 to 24 parts by weight, the cationic monomer is 0 to 24 parts by weight, and the functional monomer having a fluorescent structure is 0.1 to 10 parts by weight; 0.1-2 parts of cross-linking agent, 0.5-5 parts of emulsifier, 0.01-0.1 part of initiator, 10-60 parts of oil-soluble solvent and 25-55 parts of water.

8. The polymeric microsphere emulsion according to any one of claims 5 to 7, wherein said non-ions are selected from vinyl group containing amide monomers, preferably from at least one of acrylamide, methacrylamide, N-isopropylacrylamide, N-dipropylacrylamide, N-diethylacrylamide, N-methylolacrylamide, N-vinylformamide and N-vinylacetamide; and/or

The cationic monomer is selected from a vinyl-containing quaternary ammonium salt monomer, preferably at least one of dimethyl diallyl quaternary ammonium salt, dimethylamino ethyl methacrylate quaternary ammonium salt and dimethylamino ethyl acrylate quaternary ammonium salt; and/or

The anionic monomer is selected from carboxylic acid or sulfonic acid monomers containing vinyl, preferably at least one of acrylic acid, methacrylic acid, 2-acrylamido-2-methylpropanesulfonic acid, vinylbenzenesulfonic acid, vinylsulfonic acid or salts thereof; and/or

The functional monomer with the fluorescent structure is selected from at least one of 4, 4-dihydroxy tetraphenyl ethylene, vinyl carbazole, 1, 8-naphthalimide, 2-allyloxynaphthalene-6, 8-potassium disulfonate, styrene fluorescein derivative and styrene coumarin derivative; and/or

The water is deionized water, and/or

The cross-linking agent is selected from polyvinyl organic matters, preferably at least one selected from divinylbenzene, divinyl bisacyloxyamide, triethylene diamine, diethylenetriamine, divinyl biphenyl and butylene acrylate; and/or

The oil-soluble solvent is at least one selected from petroleum fractions, carboxylic acid esters, diester and vegetable oil, and is preferably white oil and/or solvent oil; and/or

The emulsifier is at least one selected from the group consisting of a sorbitan fatty acid ester, an alkylphenol ethoxylate, a sorbitan polyoxyethylene fatty acid ester and a fatty alcohol polyoxyethylene ether; and/or

The first initiator is at least 1 selected from sulfite, bisulfite, azobisisobutyronitrile, azobisisobutyramidine hydrochloride and azobisisobutyrimidazoline hydrochloride; and/or

The second initiator is selected from at least one of peroxides and persulfates.

9. Use of the polymer microsphere emulsion according to any one of claims 1 to 4 or obtained by the preparation method according to any one of claims 5 to 8 in oilfield exploitation, in particular in profile control plugging and underground tracing.

10. A method for profile plugging and subsurface tracking for oilfield production, comprising:

step S1: mixing different functional monomers with fluorescent structures, the polymer microsphere emulsion with different particle sizes according to any one of claims 1 to 4 or the polymer microsphere emulsion obtained by the preparation method according to any one of claims 5 to 8 with water to obtain solutions containing different functional monomers with fluorescent structures and polymer microsphere emulsions with different particle sizes respectively;

step S2: mixing the solutions containing different functional monomers with fluorescent structures and polymer microsphere emulsions with different particle sizes to obtain a mixed solution;

step S3: performing an injection experiment or a field profile control experiment on the mixed solution, and collecting produced liquid;

step S4: performing fluorescence and particle size tests on the produced liquid, and analyzing the particle size and the content of the polymer microspheres in the produced liquid;

step S5: calculating the radius of pore throat according to the results of the particle size and the content of the polymer microspheres in the produced liquid,

preferably, the concentration of the solution containing the polymer microsphere emulsion with different particle sizes is 0.1-1%, and preferably 0.1-0.5%.

Technical Field

The invention relates to the field of profile control and plugging of oil fields, in particular to a polymer microsphere emulsion and a preparation method and application thereof.

Background

At present, the heterogeneity of oil fields in China is severe, and because of long-term water injection and washing, underground rock strata generate a large number of dominant pore canals and coexist with small pore canals which can not be reached by water, so that the efficiency of enhanced oil recovery is reduced, and the cost is increased.

The deep profile control technology is a good technology for controlling displacement water and underground water. At present, the main deep profile control technology at home and abroad is the use of pre-crosslinked polymer microspheres.

Due to the serious heterogeneity, the radius distribution of underground pore throats is wide, small, several nanometers and several micrometers, which causes great influence on the application of the polymer microspheres. According to a general pore throat matching theory, the diameter of the microsphere needs to be distributed in the range of 1/3-1.2 times of the diameter of the pore throat to effectively plug an underground passage, the too large radius of the microsphere easily causes near-well plugging and cannot play a role in deep profile control, and the too small radius of the microsphere easily forms channeling and cannot effectively plug, so that the underground pore throat size is required to be tested or estimated before profile control is carried out by using the microsphere, but the deviation of the prior art is large, and even if relevant data is obtained, the problem that the microsphere-pore throat is not matched can still be encountered during profile control experiments.

Disclosure of Invention

One of the main technical problems to be solved by the invention is to provide a polymer microsphere emulsion with a specific fluorescence function aiming at the problem that the size of an oil field underground pore passage in the prior art cannot be correctly tested, wherein the polymer microsphere has a characteristic fluorescence spectrum, quantitative analysis can be carried out in produced liquid, and the calculation of the underground pore throat radius is realized through the analysis of the produced liquid.

The second technical problem to be solved by the invention is to provide a preparation method of polymer microspheres corresponding to the first technical problem, the method obtains a series of polymer microsphere emulsions with different polymer microsphere particle sizes by reverse emulsion polymerization and controlling the polymerization reaction process, the polymer microsphere emulsions can be directly prepared in high-salt water, and the obtained polymer microsphere system can effectively block underground pore throats in a certain range through controllable water absorption expansion and aging degradation processes, so that the purpose of deep profile control can be achieved.

The invention aims to solve the technical problem and provides an application method of polymer microspheres in oil extraction in an oil field, which corresponds to the solution of one of the technical problems.

On the basis of the theory of profile control plugging and pore throat matching of polymer microspheres, the invention adds fluorescent monomers into the microspheres, utilizes the characteristic color development function of the fluorescent monomers and adds polymer microsphere solution with multiple particle sizes to detect the size of an underground pore passage while performing profile control plugging on a stratum, thereby obtaining the tracing/profile control plugging composite polymer microsphere emulsion.

In a first aspect, the present invention provides a polymeric microsphere emulsion comprising polymeric microspheres, an oil-soluble solvent, and water, wherein the polymeric microspheres contain fluorescent structural units.

According to some embodiments of the invention, the fluorescent building block is derived from a functional monomer having a fluorescent structure.

According to some embodiments of the present invention, the functional monomer having a fluorescent structure is at least one selected from the group consisting of 4, 4-dihydroxytetraphenylethylene, vinylcarbazole, 1, 8-naphthalimide, potassium 2-allyloxynaphthalene-6, 8-disulfonate, a styryl fluorescein derivative, and a styryl coumarin derivative.

According to some embodiments of the invention, the oil-soluble solvent is selected from at least one of petroleum fractions, carboxylic acid esters, diesters, and vegetable oils.

According to a preferred embodiment of the invention, the petroleum fraction is a white oil and/or a solvent oil.

According to some embodiments of the invention, the polymeric microsphere emulsion comprises, in parts by weight: 15-35 parts of polymer microspheres and 10-60 parts of oil-soluble solvent; 25-55 parts of water.

According to some embodiments of the invention, the water is deionized water.

According to some embodiments of the present invention, the polymeric microspheres are polymerized from a nonionic monomer, an anionic monomer, a cationic monomer, and a functional monomer having a fluorescent structure by using a crosslinking agent.

The polymer microsphere emulsion provided by the invention is an inverse emulsion containing water, white oil and monodisperse polymer microspheres obtained by inverse emulsion polymerization.

The initial particle size of the polymer microsphere is controllable. According to some embodiments of the invention, the initial particle size of the polymeric microspheres is controllable in the range of 100nm to 2 μm.

In a second aspect, the present invention provides a method of preparing a polymeric microsphere emulsion, comprising:

step A: mixing a nonionic monomer, an anionic monomer, a functional monomer with a fluorescent structure, a first initiator, a cross-linking agent and an optional cationic monomer with water to obtain a water phase;

and B: mixing an emulsifier and an oil-soluble solvent to obtain an oil phase;

and C: mixing the water phase with the oil phase, and emulsifying to obtain an inverse emulsion;

step D: and mixing the inverse emulsion with a second initiator to carry out polymerization reaction to obtain the polymer microsphere emulsion.

According to some embodiments of the present invention, polymer microsphere emulsions containing different functional monomers with fluorescent structures can be obtained by adding different functional monomers with fluorescent structures into the aqueous phase.

According to some embodiments of the present invention, the stirring speed of the polymerization vessel can be designed according to the particle size of the microspheres, so as to obtain an emulsion containing polymer microspheres with different particle sizes.

The polymer microsphere emulsion provided by the invention is an inverse emulsion containing water, white oil and monodisperse polymer microspheres obtained by inverse emulsion polymerization.

The initial particle size of the polymer microsphere is controllable. According to some embodiments of the invention, the polymeric microspheres have a primary particle size in the range of 100nm to 2 μm.

According to some embodiments of the invention, in step a, the total monomer concentration of the aqueous phase is between 40% and 60%.

According to some embodiments of the invention, in step C, the time of emulsification is 3-10 min.

According to a preferred embodiment of the invention, in step C, the time of emulsification is 4-8 min.

According to some embodiments of the present invention, in step D, the polymerization reaction is performed by monitoring the temperature of the reaction solution, wherein the reaction starting temperature is 8-20 ℃, the temperature rising rate is controlled to be 1-2 ℃/min, the temperature rising process of the reaction is controlled within 1 hour, and the temperature is kept for 0.5-1.5 hours after the temperature does not rise any more, so as to complete the monomer conversion.

According to a preferred embodiment of the present invention, in the step D, the polymerization reaction is carried out while monitoring the temperature of the reaction solution, the reaction starting temperature being 8 to 12 ℃.

According to some embodiments of the present invention, the amount of the nonionic monomer is 5 to 99.8 parts, the amount of the anionic monomer is 0 to 24 parts, the amount of the cationic monomer is 0 to 24 parts, the amount of the functional monomer having a fluorescent structure is 0.1 to 10 parts, the amount of the crosslinking agent is 0.1 to 2 parts, the amount of the emulsifier is 0.5 to 5 parts, the amount of the initiator is 0.01 to 0.1 part, the amount of the oil-soluble solvent is 10 to 60 parts, and the amount of the water is 25 to 55 parts by weight.

According to some embodiments of the invention, the nonionic is selected from vinyl group-containing amide monomers.

According to a preferred embodiment of the present invention, the nonionic monomer is selected from at least one of acrylamide, methacrylamide, N-isopropylacrylamide, N-dipropylacrylamide, N-diethylacrylamide, N-methylolacrylamide, N-vinylformamide and N-vinylacetamide.

According to some embodiments of the invention, the cationic monomer is selected from a vinyl-containing quaternary ammonium salt monomer.

According to a preferred embodiment of the present invention, the cationic monomer is selected from at least one of dimethyl diallyl quaternary ammonium salt, dimethylamino ethyl methacrylate quaternary ammonium salt and dimethylamino ethyl acrylate quaternary ammonium salt.

According to some embodiments of the invention, the anionic monomer is selected from vinyl-containing carboxylic or sulfonic monomers.

According to a preferred embodiment of the present invention, the anionic monomer is selected from at least one of acrylic acid, methacrylic acid, 2-acrylamido-2-methylpropanesulfonic acid, vinylbenzenesulfonic acid, vinylsulfonic acid, or salts thereof.

According to some embodiments of the present invention, the functional monomer having a fluorescent structure is at least one selected from the group consisting of 4, 4-dihydroxytetraphenylethylene, vinylcarbazole, 1, 8-naphthalimide, potassium 2-allyloxynaphthalene-6, 8-disulfonate, a styryl fluorescein derivative, and a styryl coumarin derivative.

According to some embodiments of the invention, the water is deionized water.

According to some embodiments of the invention, the cross-linking agent is selected from polyvinyl type organics.

According to a preferred embodiment of the present invention, the crosslinking agent is selected from at least one of divinylbenzene, bisvinylbisacyloxyamide, triethylenediamine, diethylenetriamine, divinylbiphenyl and crotyl acrylate.

According to some embodiments of the invention, the oil-soluble solvent is selected from at least one of petroleum fractions, carboxylic acid esters, diesters, and vegetable oils.

According to a preferred embodiment of the invention, the oil-soluble solvent is selected from white oil and/or mineral spirits.

According TO some embodiments of the invention, the emulsifier is selected from at least one of a sorbitan fatty acid ester (span), an alkylphenol ethoxylate (OP/NP), a sorbitan polyoxyethylene ether fatty acid ester (tween) and a fatty alcohol polyoxyethylene ether (AEO/TO).

According TO a preferred embodiment of the invention, the emulsifier is a span/TO blend emulsifier.

According to some embodiments of the invention, the first initiator is selected from at least one of sulfite, bisulfite, Azobisisobutyronitrile (AIBN), azobisisobutyramidine hydrochloride (AIBA), and azobisisobutyrimidazoline hydrochloride (AIBI).

According to a preferred embodiment of the present invention, the first initiator is selected from at least two of sulfite, Azobisisobutyronitrile (AIBN), azobisisobutyramidine hydrochloride (AIBA) and azobisisobutyrimidazoline hydrochloride (AIBI).

According to some embodiments of the invention, the second initiator is selected from at least one of a peroxide and a persulfate.

According to some embodiments of the invention, the polymeric microsphere emulsion comprises, in parts by weight: 15-35 parts of polymer microspheres and 10-60 parts of oil-soluble solvent; 25-55 parts of water.

In the above technical solution, the polymer microsphere may be a crosslinked polymer microsphere containing an acrylamide structural unit, a polyvinyl crosslinking agent, and other functional monomers, and is not limited to binary copolymerization, and may also be a ternary or multicomponent copolymer, such as but not limited to a polymer microsphere obtained by copolymerization of 2-acrylamido-2-methylpropanesulfonic acid, acrylamide, vinylcarbazole, and crosslinking of crotyl acrylate.

In a third aspect, the present invention provides the use of a polymeric microsphere emulsion according to the first aspect or a polymeric microsphere emulsion obtained by the method of preparation according to the second aspect in oilfield exploitation.

According to some embodiments of the invention, the application is in profile plugging and subsurface tracing.

In a fourth aspect, the present invention provides a method of profile control plugging and subsurface tracing in oilfield production, comprising:

step S1: mixing different functional monomers with fluorescent structures, the polymer microsphere emulsion with different particle sizes obtained by the first aspect or the polymer microsphere emulsion obtained by the preparation method according to the second aspect with water to respectively obtain solutions containing different functional monomers with fluorescent structures and polymer microsphere emulsions with different particle sizes;

step S2: mixing the solutions containing different functional monomers with fluorescent structures and polymer microsphere emulsions with different particle sizes to obtain a mixed solution;

step S3: performing an injection experiment or a field profile control experiment on the mixed solution, and collecting produced liquid;

step S4: performing fluorescence and particle size tests on the produced liquid, and analyzing the particle size and the content of the polymer microspheres in the produced liquid;

step S5: and calculating the radius of the pore throat according to the results of the particle size and the content of the polymer microspheres in the produced liquid.

According to some embodiments of the present invention, polymer microsphere emulsions containing different functional monomers with fluorescent structures can be obtained by adding different functional monomers with fluorescent structures into the aqueous phase.

According to some embodiments of the present invention, the stirring speed of the polymerization vessel can be designed according to the particle size of the microspheres, so as to obtain an emulsion containing polymer microspheres with different particle sizes.

According to some embodiments of the invention, the concentration of the solution containing the emulsion of polymeric microspheres of different particle size is between 0.1% and 1%.

According to a preferred embodiment of the present invention, the concentration of the solution containing the polymer microsphere emulsion with different particle sizes is 0.1% -0.5%.

In the invention, the microspheres with different particle sizes are compounded, and the microspheres with different particle sizes can be quantitatively tested through specific fluorescence reaction, so that the underground pore diameter is tested while profile control and plugging are realized, and the size of the underground pore diameter is analyzed by measuring the microspheres in the produced water, so that the aim of tracing the fluidity of the injected liquid while deep profile control can be achieved.

By adopting the polymer microsphere emulsion provided by the invention, the produced water of the oil field with high mineralization can be directly used for preparation; the polymer microsphere emulsion is pretreated, and the operation is simple and convenient; the produced liquid can be directly analyzed for the particle size and the concentration of the microspheres, so that the underground aperture is calculated, the test process is simple and quick, and a better technical effect is achieved.

Detailed Description

The invention is further illustrated by the following specific examples. The following illustrative examples are provided to further illustrate the present invention and are not intended to limit the scope of the invention.

For the test of the produced liquid, a Nano ZS nanometer particle size meter which is produced by Marwin company is used for testing the particle size, an F-4600 fluorescence spectrometer which is produced by Hitachi company is used for measuring the fluorescence performance and the concentration analysis, and a TOC-TN which is produced by Shimadzu company is used for ordering.

Example 1

Preparing an aqueous solution with a total monomer concentration of 60% by using 85% of acrylamide, 14.9% of 2-acrylamido-2-methylpropanesulfonic Acid (AMPS) and 0.1% of vinylcarbazole, and adding 0.01% of sodium bisulfite, 0.05% of azobisisobutyronitrile and 0.1% of bisvinylbisacyloxyamide to the aqueous solution to obtain an aqueous phase; SPAN5 was mixed with TO30 at a ratio of 1: 1, preparing the mixture into 110# solvent oil with the total concentration of 2% to obtain an oil phase, and mixing the water phase and the oil phase in a ratio of 1: 1, dripping 0.1 percent potassium peroxide solution at the rotating speed of 500rpm for polymerization reaction after emulsification to obtain the polymer microsphere emulsion with the microsphere initial particle size of 100 nm.

Preparing a 60% aqueous solution from 85% acrylamide, 14.8% 2-acrylamido-2-methylpropanesulfonic Acid (AMPS) and 0.2% potassium 2-allyloxynaphthalene-6, 8-disulfonate to obtain a water phase; SPAN5 was mixed with TO30 at a ratio of 1: 1, preparing the mixture in 110# solvent oil, wherein the total concentration is 2% in proportion, obtaining an oil phase, and the proportion of the water phase to the oil phase is 1: 1, after emulsification, dripping 0.1 percent potassium peroxide solution at the rotating speed of 200rpm for polymerization to obtain the polymer microsphere emulsion with the microsphere initial particle size of 800 nm.

A 60% aqueous solution was prepared using 85% acrylamide, 14.5% 2-acrylamido-2-methylpropanesulfonic Acid (AMPS), and 0.5% 4- [4- (3, 5-dimethyl-4-styryl) benzoylamino ] fluorescein, at a ratio of aqueous to oil phase of 1: 1, after emulsification, dripping 0.1 percent potassium peroxide solution at the rotating speed of 100rpm for polymerization to obtain polymer microsphere emulsion with the microsphere initial particle size of 2000 nm.

The three emulsions were formulated as 0.2% solutions, in a 1: 1: 1, mixing to obtain a mixed solution, and testing the fluorescence spectrum and the particle size of the injected liquid.

Filling a sand filling pipe with the porosity of 3000mD and the length of 30cm, injecting by using the mixed solution, and collecting the produced liquid.

The produced liquid is subjected to fluorescence spectrum measurement, no 4- [4- (3, 5-dimethyl-4-styryl) benzoylamino ] fluorescein signal exists, the vinylcarbazole signal is the same as that of the injected liquid, and the 2-allyloxynaphthalene-6, 8-disulfonic acid potassium signal is about 60% of that of the injected liquid.

The produced liquid is tested for particle size, and the average value of the particle size is reduced compared with the average value of the particle size of the injected liquid.

And calculating according to the pore matching principle on the basis of the particle size of the microspheres in the effluent, thereby judging that the pore diameter of the sand-packed pipe with the permeability is between 300nm and 670 nm.

The permeability of the sand filling pipe subjected to microsphere profile control obtained by injecting the microspheres into subsequent water drive is about 500mD, and the microspheres play a role in effective profile control and plugging.

Example 2

Preparing a 60% aqueous solution from 80% acrylamide, 19.9% 2-acrylamido-2-methylpropanesulfonic Acid (AMPS) and 0.1% vinylcarbazole, and adding 0.01% sodium bisulfite, 0.05% azobisisobutyramidine sodium hydrochloride and 0.1% bisvinylbisacyloxyamide to the aqueous solution to obtain an aqueous phase; SPAN5 was mixed with TO30 at a ratio of 1: 1, preparing the total concentration of 2% in 5# white oil to obtain an oil phase, wherein the proportion of the water phase to the oil phase is 1: 1, dripping 0.1 percent potassium peroxide solution at the rotating speed of 500rpm for polymerization after emulsification to obtain polymer microsphere emulsion with the microsphere initial particle size of 100 nm.

Preparing 60% aqueous solution by using 80% of acrylamide, 19.8% of 2-acrylamido-2-methylpropanesulfonic Acid (AMPS) and 0.2% of potassium 2-allyloxynaphthalene-6, 8-disulfonate, and adding 0.01% of sodium bisulfite, 0.05% of azobisisobutyronitrile and 0.1% of bisvinylbisacyloxyamide to the aqueous solution to obtain an aqueous phase; SPAN5 was mixed with TO30 at a ratio of 1: 1, preparing the total concentration of 2% in 5# white oil to obtain an oil phase, wherein the proportion of the water phase to the oil phase is 1: 1, dripping 0.1 percent potassium peroxide solution at the rotating speed of 400rpm for polymerization after emulsification to obtain polymer microsphere emulsion with the microsphere initial particle size of 300 nm.

Preparing a 60% aqueous solution from 80% acrylamide, 19.5% 2-acrylamido-2-methylpropanesulfonic Acid (AMPS) and 0.5% 4- [4- (3, 5-dimethyl-4-styryl) benzoylamino ] fluorescein, and adding 0.01% sodium bisulfite, 0.05% azobisisobutyronitrile and 0.1% bisvinylbisacyloxyamide to the aqueous solution to obtain an aqueous phase; SPAN5 was mixed with TO30 at a ratio of 1: 1, preparing the total concentration of 2% in 5# white oil to obtain an oil phase, wherein the proportion of the water phase to the oil phase is 1: 1, dripping 0.1 percent potassium peroxide solution at the rotating speed of 300rpm for polymerization after emulsification to obtain the polymer microsphere emulsion with the microsphere initial particle size of 500 nm.

The three emulsions were formulated as 0.2% solutions, in a 1: 1: 1, mixing to obtain a mixed solution, and testing the fluorescence spectrum and the particle size of the injected liquid.

Filling a sand filling pipe with the porosity of 1000mD and the length of 30cm, injecting by using the mixed solution, and collecting the produced liquid.

The produced liquid is subjected to fluorescence spectrum measurement, no 4- [4- (3, 5-dimethyl-4-styryl) benzoylamino ] fluorescein signal exists, the vinylcarbazole signal is the same as that of the injected liquid, and the 2-allyloxynaphthalene-6, 8-disulfonic acid potassium signal is about 20% of that of the injected liquid.

The produced liquid is tested for particle size, and the average value of the particle size is reduced compared with the average value of the particle size of the injected liquid.

The pore diameter of the sand pack pipe with the permeability is judged to be about 250 nm.

The permeability of the sand filling pipe subjected to microsphere profile control obtained by injecting the microspheres into subsequent water drive is about 300mD, and the microspheres play a role in effective profile control and plugging.

Example 3

The only difference from example 1 is that three different emulsions with different primary particle sizes were formulated as 0.05% solutions, in a 1: 1: 1, mixing to obtain a mixed solution, and testing the fluorescence spectrum and the particle size of the injected liquid.

Filling a sand filling pipe with the porosity of 3000mD and the length of 30cm, injecting by using the mixed solution, and collecting the produced liquid.

The produced liquid is measured by fluorescence spectrum, no 4- [4- (3, 5-dimethyl-4-styryl) benzoylamino ] fluorescein signal exists, and the signals of vinylcarbazole and 2-allyloxynaphthalene-6, 8-potassium disulfonate are the same as those of the injection liquid.

The produced liquid is tested for particle size, and the average value of the particle size is reduced compared with the average value of the particle size of the injected liquid.

And calculating according to the pore matching principle on the basis of the particle size of the microspheres in the effluent, thereby judging that the pore diameter of the sand-packed pipe with the permeability is between 300nm and 1600 nm.

The permeability of the sand-filled pipe subjected to microsphere profile control obtained by injecting the microspheres into subsequent water drive is about 800mD, and the microspheres play a role in effective profile control and plugging.

Example 4

The only difference from example 1 is that three different emulsions with different primary particle sizes were formulated as 0.5% solutions, in a ratio of 1: 1: 1, mixing to obtain a mixed solution, and testing the fluorescence spectrum and the particle size of the injected liquid.

Filling a sand filling pipe with the porosity of 3000mD and the length of 30cm, injecting by using the mixed solution, and collecting the produced liquid.

The produced liquid is subjected to fluorescence spectrum measurement, no 4- [4- (3, 5-dimethyl-4-styryl) benzoylamino ] fluorescein signal exists, the vinylcarbazole signal is the same as that of the injected liquid, and the 2-allyloxynaphthalene-6, 8-disulfonic acid potassium signal is about 25% of that of the injected liquid.

The produced liquid is tested for particle size, and the average value of the particle size is reduced compared with the average value of the particle size of the injected liquid.

And calculating according to the pore matching principle on the basis of the particle size of the microspheres in the effluent, thereby judging that the pore diameter of the sand-packed pipe with the permeability is between 300nm and 670 nm.

The permeability of the sand filling pipe subjected to microsphere profile control obtained by injecting the microspheres into subsequent water drive is about 400mD, and the microspheres play a role in effective profile control and plugging.

Comparative example 1

Preparing a 60% aqueous solution from 80% acrylamide, 19.9% 2-acrylamido-2-methylpropanesulfonic Acid (AMPS) and 0.1% vinylcarbazole, and adding 0.01% sodium bisulfite, 0.05% azobisisobutyronitrile and 0.1% bisvinylbisacyloxyamide to the aqueous solution to obtain an aqueous phase; SPAN5 was mixed with TO30 at a ratio of 1: 1, preparing the total concentration of 2% in 5# white oil to obtain an oil phase, wherein the proportion of the water phase to the oil phase is 1: 1, dripping 0.1 percent potassium peroxide solution at the rotating speed of 300rpm for polymerization after emulsification to obtain the polymer microsphere emulsion with the microsphere initial particle size of 500 nm.

The emulsion was prepared into a 0.2% solution as an injection solution, and the fluorescence spectrum and particle size of the injection solution were measured.

And (3) performing fluorescence spectrum measurement on the produced liquid, wherein no vinylcarbazole signal exists.

The produced liquid is subjected to particle size test, and no result can be obtained.

The sand packed pipe thus judged to have such a permeability has a pore diameter of 300nm or less, and no more specific pore diameter information can be obtained.

Comparative example 2

Preparing solution with 0.1 percent of ammonium peroxide concentration as initiator solution

Preparing a 60% aqueous solution from 80% acrylamide and 20% 2-acrylamido-2-methylpropanesulfonic Acid (AMPS), and adding 0.01% sodium bisulfite, 0.05% azobisisobutyronitrile and 0.1% bisvinylbisacyloxyamide to the aqueous solution to obtain an aqueous phase; SPAN5 was mixed with TO30 at a ratio of 1: 1, preparing the total concentration of 2% in 5# white oil to obtain an oil phase, wherein the proportion of the water phase to the oil phase is 1: 1, dripping 0.1 percent potassium peroxide solution at the rotating speed of 300rpm for polymerization after emulsification to obtain the polymer microsphere emulsion with the microsphere initial particle size of 500 nm.

The emulsion is prepared into 0.2 percent solution as injection liquid, and the fluorescence spectrum, TN and particle size of the injection liquid are tested, and the injection liquid has no fluorescence signal.

The produced liquid is subjected to fluorescence spectrum measurement, and a trace amount of fluorescence signals exist, so that the generation of chemicals cannot be judged.

The produced liquid is subjected to particle size test, and no result can be obtained.

And (4) carrying out TOC-TN test on the produced liquid, wherein TN does not exist in the produced liquid.

And thus specific aperture information cannot be obtained.

It should be noted that the above-mentioned embodiments are only for explaining the present invention, and do not constitute any limitation to the present invention. The present invention has been described with reference to exemplary embodiments, but the words which have been used herein are words of description and illustration, rather than words of limitation. The invention can be modified, as prescribed, within the scope of the claims and without departing from the scope and spirit of the invention. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein, but rather extends to all other methods and applications having the same functionality.