Particle oil-displacing agent based on cross-linking of amino acid polymer and preparation method and application of particle oil-displacing agent

Abstract

The invention discloses a particle oil-displacing agent based on amino acid polymer crosslinking as well as a preparation method and application of the particle oil-displacing agent. The preparation method comprises the following steps: (1) preparing an amino acid polymer cross-linking agent solution; and (2) in the presence of an initiator, an accelerant and water serving as a solvent, carrying out polymerization reaction on the amino acid polymer cross-linking agent solution obtained in the step (1) and acrylamide, and after the reaction is finished, carrying out post-treatment to obtain the particle oil displacement agent based on amino acid polymer cross-linking. The invention discloses application of a particle oil displacement agent based on amino acid polymer crosslinking as an oil displacement agent or a plugging agent in tertiary oil recovery. The invention has the following beneficial effects: 1, the toxicity is small, the triple advantages of oil displacement, water plugging and environmental protection are integrated, and green oil displacement is realized; 2, the mechanical property is very good; and 3, the oil displacement efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the field of petroleum exploitation, and in particular relates to a particle oil displacement agent based on amino acid polymer cross-linking, and a preparation method and application thereof. Background Art

[0002] Oil is the "blood" of modern industry, a valuable non-renewable resource, and an indispensable strategic resource for national survival and development. It plays an immeasurable role in ensuring national economic and social development and national defense security.

[0003] At present, the production of major oil fields in China has entered the stage of medium-to-high water content development. In order to improve the recovery rate of oil, injecting specific chemical reagents, namely chemical oil-displacing agents, into oil wells to achieve plugging or profile adjustment of the water-producing layer of the oil reservoir, thereby controlling the water output of the oil field, is a method that is currently widely used and effective. For example, Chinese invention patent application CN101798503A discloses the preparation and application of a new polymer oil-displacing agent for improving oil recovery. The polymer oil-displacing agent uses acrylamide (AM)-acrylic acid (AA)-hydrophobic monomers as reaction monomers, and the hydrophobic monomer is dimethylallyl p-alkylbenzyl ammonium chloride, etc., and synthesizes a new type of associative polymer with different hydrophobic monomers and contents by free radical polymerization. For another example, Chinese invention patent application CN104861950A discloses a supramolecular linear polyacrylamide oil-displacing agent, which is composed of the following components: adamantane-terminated polyacrylamide, β-cyclodextrin dimer, additives, deoxidizer, and water; a method for preparing a supramolecular linear polyacrylamide oil-displacing agent, which is composed of the following steps: a. preparing adamantane-terminated polyacrylamide; b. adding additives and deoxidizer to water, stirring evenly, adding adamantane-terminated polyacrylamide, stirring and letting stand to react, adding β-cyclodextrin dimer, stirring and letting stand to react, and the resulting solution is the supramolecular linear polyacrylamide oil-displacing agent.

[0004] However, in the above-mentioned technical scheme, the underground environment is complex, and the long-term injection of water and high-intensity scouring of produced fluids cause the destruction of the reservoir rock structure, forming ultra-high permeability strips or dominant channels between the injection and production wells, further aggravating the reservoir heterogeneity, causing the oil displacement agent solution to advance along the dominant channel, seriously affecting the water drive and polymer drive development effects.

[0005] Chinese invention patent CN104327821B discloses an amphiphilic modified chitosan degradable oil-displacing agent and a preparation method thereof. The oil-displacing agent uses chitosan as a macromolecular monomer, acrylamide and acrylic acid as water-soluble monomers, 2-alkyl acrylamide alkyl sulfonate sodium as a hydrophobic monomer, and azobisisobutylamidine hydrochloride as an initiator. In the absence of an emulsifier, hydrophilic groups and hydrophobic units are introduced in a one-step method to copolymerize to form a "worm"-shaped polymer. However, the above technical solution has the following shortcomings: 1) The biomass macromolecular cross-linking agent selected for the oil-displacing agent requires specific biological enzymes to be degraded, and the underground high-temperature and high-salt environment is complex, and the biological enzymes may not be active, so degradation cannot be ensured to meet environmental protection requirements; 2) The oil-displacing agent has a special worm-like structure, which is self-assembled by hydrophilic and hydrophobic units under static water conditions, relying on intermolecular hydrophobic or hydrophilic association forces. This intermolecular interaction force is relatively small, and the oil-displacing agent is subjected to external pressure or pore shear force when it migrates underground, and whether it can maintain this self-assembled structure cannot be verified. Summary of the invention

[0006] Purpose of the invention: In view of the fact that the oil-displacing agent in the above-mentioned prior art advances along the dominant channel, seriously affecting the development effect of water flooding and polymer flooding, the present invention discloses a granular oil-displacing agent based on amino acid polymer cross-linking, and its preparation method and application.

[0007] The present invention selects amino acid polymer as a matrix and a cross-linking agent to prepare a dual network with both chemical and physical cross-linking. When in use, the particle oil displacement agent enters the ultra-high permeability strip or the dominant channel, and then blocks the ultra-high permeability strip or the dominant channel, so that the oil displacement agent enters the low permeability channel, improving the oil displacement efficiency. When unblocking is required, the amino acid polymer cross-linking agent itself can be converted from a cross-linked state insoluble in water to a linear water-soluble state by increasing the injection pressure, thereby achieving degradation.

[0008] Technical solution: A particle oil-displacing agent based on amino acid polymer cross-linking, wherein the particle oil-displacing agent based on amino acid polymer cross-linking contains structural unit A, structural unit B and structural unit C, wherein:

[0009] The structural unit A is derived from an amino acid polymer;

[0010] The structural unit B is derived from allyl glycidyl ether or glycidyl methacrylate;

[0011] The structural unit C is derived from acrylamide;

[0012] Based on the weight of the amino acid polymer cross-linked particulate oil-displacing agent, the content of the structural unit A is 0.0014 wt %-0.0225 wt %, the content of the structural unit B is 0.0173 wt %-0.0675 wt %, and the content of the structural unit C is 99.3073 wt %-99.9813 wt %.

[0013] Furthermore, the amino acid polymer is one of polylysine, polyaspartic acid, polysarcosine, polyglutamic acid, and polyleucine.

[0014] Furthermore, the particle size of the amino acid polymer cross-linked granular oil-displacing agent is between 20 mesh and 200 mesh, preferably between 100 mesh and 140 mesh.

[0015] The preparation method of the above-mentioned amino acid polymer cross-linked particle oil displacement agent comprises the following specific steps:

[0016] (1) preparing an amino acid polymer cross-linking agent solution;

[0017] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0018] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0019] One part of amino acid polymer and 3-12 parts of allyl glycidyl ether or glycidyl methacrylate are dissolved in 87-96 parts of water to obtain a mixed solution, the pH value of the mixed solution is adjusted to 9-10 by alkaline substances, and a polymerization reaction is carried out at 60-80° C. for at least 4 hours to obtain an amino acid polymer crosslinker solution.

[0020] Furthermore, the alkaline substance is one of sodium hydroxide, potassium hydroxide and sodium bicarbonate.

[0021] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0022] The amino acid polymer cross-linking agent solution obtained in step (1) is poured into a dialysis bag with a molecular weight of no more than 3000, and dialyzed in deionized water or distilled water for at least 7 days.

[0023] Furthermore, the initiator in step (2) is one of potassium persulfate, ammonium persulfate and sodium persulfate.

[0024] Furthermore, the promoter in step (2) is tetramethylethylenediamine or pentamethyldiethylenetriamine.

[0025] Furthermore, the specific steps of step (2) are as follows:

[0026] Dissolve acrylamide in water, add the amino acid polymer crosslinker solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 8.5-9, then introduce nitrogen or inert gas to remove dissolved oxygen in the mixed solution, add an initiator at 12-18°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0027] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0028] Furthermore, the drying process control conditions of the block gel after cutting are: 70-80° C., forced air drying for 4-5 hours.

[0029] Furthermore, the process control conditions of crushing are: crushing with a high-speed crusher at a speed of not less than 10000RPM for at least 15s.

[0030] Furthermore, the process control conditions of screening are: screening with a 20-mesh screen and a 200-mesh screen to obtain a particle oil displacement agent with a particle size between 20 mesh and 200 mesh, preferably

[0031] The granular oil displacement agent with a particle size between 0.1 and 0.15 mm was obtained by sieving with a 100-mesh sieve and a 140-mesh sieve.

[0032] Furthermore, in step (2):

[0033] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is (0.5-3): (0.02-0.04): (0.02-0.04): (40-80): (140-280).

[0034] Furthermore, the water is one of deionized water and distilled water.

[0035] The amino acid polymer cross-linked granular oil-displacing agent is prepared by any one of the above preparation methods.

[0036] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as an oil displacement agent in tertiary oil recovery.

[0037] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as a plugging agent in tertiary oil recovery.

[0038] In the process of preparing gel by acrylamide polymerization, the amino acid polymer cross-linking agent is used as the cross-linking center, and the polymerization of acrylamide is carried out in deionized water, under the protection of inert gas, and in the presence of a redox initiation system (where the initiator is an oxidant and the promoter is a reducing agent).

[0039] The inert gas used in the present invention can be helium, argon, neon, etc., without particular limitation. The introduction of the inert gas can not only remove the oxygen in the reactor, but also has a stirring effect, so the inert gas needs to be introduced before the reaction system starts polymerization.

[0040] The particle oil-displacing agent based on amino acid polymer cross-linking of the present invention is a dual network structure in which chemical cross-linking and physical cross-linking structures coexist. Since the particle oil-displacing agent based on amino acid polymer cross-linking is not only a multifunctional cross-linking agent, but also has a macromolecule with a linear structure, it is further controlled by the termination mode and reaction kinetics of polyacrylamide free radical polymerization, and the double bonds thereon do not completely play a chemical cross-linking role, but will form a large number of branched chain structures, and these branched chains will be entangled with each other to form a physical entanglement network. In the process of force, the physical entanglement network will be preferentially broken to dissipate energy, and the linear macromolecular cross-linking agent will also continuously adjust its own conformation in this process, so that the hydrogel network tends to be homogenized, avoiding stress concentration, so such a structure gives this macromolecular cross-linked gel excellent mechanical properties.

[0041] The present invention prepares a granular oil-displacing agent with degradable cross-linking sites, prepares a suspension and injects it into the ground. The granular oil-displacing agent that absorbs water and swells preferentially enters the ultra-high permeability strip or the dominant channel for plugging, so that the subsequent displacement fluid enters the low permeability channel that has not been displaced for oil displacement. The blocked granular oil-displacing agent then degrades into linear components soluble in water at high temperature and further increases the viscosity of the displacement fluid, thereby improving the oil displacement effect. Therefore, the granular oil-displacing agent can achieve the effect of first plugging and then displacing.

[0042] Compared with the prior art, the present invention has the following advantages:

[0043] 1. With amino acid polymer cross-linking agent as the core, the particle oil displacement agent product is obtained through the free radical polymerization reaction of acrylamide; due to the inherent chemical properties of amino acid polymer, its toxicity is relatively low, so the prepared particle oil displacement agent gel has good environmental performance, and it combines the triple advantages of oil displacement, water plugging and environmental protection at the molecular structure design level, realizing green oil displacement;

[0044] 2. The novel particle oil-displacing agent of the present invention has good mechanical properties because it has a dual network of chemical and physical cross-linking, and the cross-linking agent gives the hydrogel a uniform network structure;

[0045] 3. When in use, the granular oil displacement agent enters the ultra-high permeability strip or dominant channel, and then blocks the ultra-high permeability strip or dominant channel, allowing the oil displacement agent to enter the low permeability channel, thereby improving the oil displacement efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 The present invention is a flow chart of a method for preparing an amino acid polymer cross-linked particle oil-displacing agent disclosed in the present invention.

[0047] Figure 2 This is the infrared absorption spectrum of the amino acid polymer cross-linking agent solution prepared in Example 2 after post-treatment and sample preparation.

[0048] Figure 3 Schematic diagram of the storage modulus in the rheological properties of the hydrogels prepared in Examples 1-4.

[0049] Figure 4 Schematic diagram of the loss modulus in the rheological properties of the hydrogels prepared in Examples 1-4.

[0050] Figure 5 The tensile stress-strain curves of the macromolecular cross-linking agent prepared in Examples 1-4 are shown.

[0051] Figure 6 Schematic diagram of the loss modulus of the macromolecular cross-linking agents prepared in Examples 5-8.

[0052] Figure 7 This is a test curve of the oil displacement performance of the amino acid polymer cross-linked particle oil displacement agent prepared in Example 3. DETAILED DESCRIPTION

[0053] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0054] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and "including" are used in this specification, they indicate the presence of features, steps, operations and combinations thereof.

[0055] In order to enable those skilled in the art to more clearly understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in conjunction with specific embodiments.

[0056] Taking the reaction of polylysine and allyl glycidyl ether (AGE) as an example, the reaction principle of the amino acid polymer crosslinker is as follows:

[0057]

[0058] The number average molecular weight of the amino acid polymer cross-linking agent is 4100-7400.

[0059] Example 1

[0060] The preparation method of the particle oil displacement agent based on amino acid polymer cross-linking is as follows:

[0061] (1) preparing an amino acid polymer cross-linking agent solution;

[0062] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0063] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0064] One part of amino acid polymer and 3 parts of allyl glycidyl ether were dissolved in 96 parts of water to obtain a mixed solution, the pH value of the mixed solution was adjusted to 9 by an alkaline substance, and a polymerization reaction was carried out at 60° C. for 6 hours to obtain an amino acid polymer crosslinker solution.

[0065] Furthermore, the alkaline substance is sodium hydroxide.

[0066] Furthermore, the amino acid polymer is polylysine.

[0067] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0068] The amino acid polymer cross-linking agent solution obtained in step (1) was poured into a dialysis bag with a molecular weight of 3000 and dialyzed in deionized water for 7 days.

[0069] Furthermore, the initiator in step (2) is potassium persulfate.

[0070] Furthermore, the promoter in step (2) is tetramethylethylenediamine.

[0071] Furthermore, the specific steps of step (2) are as follows:

[0072] Dissolve acrylamide in water, add the amino acid polymer crosslinker solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 9, then introduce nitrogen to remove dissolved oxygen in the mixed solution, add an initiator at 12°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0073] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0074] Furthermore, the drying process control conditions of the block gel after cutting are: 70° C., forced air drying for 5 hours.

[0075] Furthermore, the process control conditions of crushing are: crushing with a high-speed crusher at a rotation speed of 10000RPM for 15s.

[0076] Furthermore, the process control conditions of screening are: using a 100-mesh sieve and a 140-mesh sieve for screening to obtain a granular oil displacement agent with a particle size between 0.1 and 0.15 mm.

[0077] In another embodiment, the process control conditions of screening are: screening with a 20-mesh sieve and a 200-mesh sieve to obtain a granular oil-displacing agent with a particle size ranging from 20 mesh to 200 mesh.

[0078] Furthermore, in step (2):

[0079] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is 0.5:0.03:0.02:60:200.

[0080] Furthermore, the water is deionized water.

[0081] The amino acid polymer cross-linked particle oil-displacing agent is prepared by the above preparation method.

[0082] The above-mentioned amino acid polymer cross-linked granular oil displacement agent is used as an oil displacement agent in tertiary oil recovery.

[0083] The above-mentioned amino acid polymer cross-linked particle oil displacement agent is used as a plugging agent in tertiary oil recovery.

[0084] Example 2

[0085] The preparation method of the particle oil displacement agent based on amino acid polymer cross-linking is as follows:

[0086] (1) preparing an amino acid polymer cross-linking agent solution;

[0087] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0088] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0089] One part of amino acid polymer and 6 parts of allyl glycidyl ether were dissolved in 93 parts of water to obtain a mixed solution, the pH value of the mixed solution was adjusted to 9 by an alkaline substance, and a polymerization reaction was carried out at 60° C. for 7 hours to obtain an amino acid polymer crosslinker solution.

[0090] Furthermore, the alkaline substance is potassium hydroxide.

[0091] Furthermore, the amino acid polymer is polylysine.

[0092] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0093] The amino acid polymer cross-linking agent solution obtained in step (1) was poured into a dialysis bag with a molecular weight of 2500 and dialyzed in deionized water for 7 days.

[0094] Furthermore, the initiator in step (2) is potassium persulfate.

[0095] Furthermore, the promoter in step (2) is tetramethylethylenediamine.

[0096] Furthermore, the specific steps of step (2) are as follows:

[0097] Dissolve acrylamide in water, add the amino acid polymer crosslinker solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 9, then introduce nitrogen to remove dissolved oxygen in the mixed solution, add an initiator at 12°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0098] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0099] Furthermore, the drying process control conditions of the block gel after cutting are 80° C. and forced air drying for 4 hours.

[0100] Furthermore, the process control conditions of crushing are: crushing with a high-speed crusher at a rotation speed of 12000RPM for 15s.

[0101] Furthermore, the granular oil displacement agent with a particle size between 0.1 and 0.15 mm is obtained by sieving with a 100-mesh sieve and a 140-mesh sieve.

[0102] In another embodiment, the process control conditions of screening are: screening with a 20-mesh sieve and a 200-mesh sieve to obtain a granular oil-displacing agent with a particle size ranging from 20 mesh to 200 mesh.

[0103] Furthermore, in step (2):

[0104] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is 1:0.03:0.02:60:200.

[0105] Furthermore, the water is deionized water.

[0106] The amino acid polymer cross-linked particle oil-displacing agent is prepared by the above preparation method.

[0107] The above-mentioned amino acid polymer cross-linked granular oil displacement agent is used as an oil displacement agent in tertiary oil recovery.

[0108] The above-mentioned amino acid polymer cross-linked particle oil displacement agent is used as a plugging agent in tertiary oil recovery.

[0109] Example 3

[0110] The preparation method of the particle oil displacement agent based on amino acid polymer cross-linking is as follows:

[0111] (1) preparing an amino acid polymer cross-linking agent solution;

[0112] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0113] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0114] One part of amino acid polymer and 9 parts of allyl glycidyl ether were dissolved in 90 parts of water to obtain a mixed solution, the pH value of the mixed solution was adjusted to 9 by an alkaline substance, and a polymerization reaction was carried out at 70° C. for 7 hours to obtain an amino acid polymer crosslinker solution.

[0115] Furthermore, the alkaline substance is sodium bicarbonate.

[0116] Furthermore, the amino acid polymer is polylysine.

[0117] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0118] The amino acid polymer cross-linking agent solution obtained in step (1) was poured into a dialysis bag with a molecular weight of 2000 and dialyzed in deionized water for 8 days.

[0119] Furthermore, the initiator in step (2) is potassium persulfate.

[0120] Furthermore, the promoter in step (2) is tetramethylethylenediamine.

[0121] Furthermore, the specific steps of step (2) are as follows:

[0122] Dissolve acrylamide in water, add the amino acid polymer crosslinker solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 9, then introduce nitrogen to remove dissolved oxygen in the mixed solution, add an initiator at 12°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0123] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0124] Furthermore, the drying process control conditions of the block gel after cutting are: 75° C., forced air drying for 4.5 hours.

[0125] Furthermore, the process control conditions of crushing are: crushing with a high-speed crusher at a rotation speed of 10000RPM for 30s.

[0126] Furthermore, the granular oil displacement agent with a particle size between 0.1 and 0.15 mm is obtained by sieving with a 100-mesh sieve and a 140-mesh sieve.

[0127] In another embodiment, the process control conditions of screening are: screening with a 20-mesh sieve and a 200-mesh sieve to obtain a granular oil-displacing agent with a particle size ranging from 20 mesh to 200 mesh.

[0128] Furthermore, in step (2):

[0129] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is 1.5:0.03:0.02:60:200.

[0130] Furthermore, the water is deionized water.

[0131] The amino acid polymer cross-linked particle oil-displacing agent is prepared by the above preparation method.

[0132] The above-mentioned amino acid polymer cross-linked granular oil displacement agent is used as an oil displacement agent in tertiary oil recovery.

[0133] The above-mentioned amino acid polymer cross-linked particle oil displacement agent is used as a plugging agent in tertiary oil recovery.

[0134] Example 4

[0135] The preparation method of the particle oil displacement agent based on amino acid polymer cross-linking is as follows:

[0136] (1) preparing an amino acid polymer cross-linking agent solution;

[0137] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0138] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0139] One part of amino acid polymer and 9 parts of glycidyl methacrylate were dissolved in 90 parts of water to obtain a mixed solution, the pH value of the mixed solution was adjusted to 9 by an alkaline substance, and a polymerization reaction was carried out at 70° C. for 7 hours to obtain an amino acid polymer crosslinker solution.

[0140] Furthermore, the alkaline substance is sodium hydroxide.

[0141] Furthermore, the amino acid polymer is polylysine.

[0142] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0143] The amino acid polymer cross-linking agent solution obtained in step (1) was poured into a dialysis bag with a molecular weight of 2800 and dialyzed in deionized water for 7 days.

[0144] Furthermore, the initiator in step (2) is potassium persulfate.

[0145] Furthermore, the promoter in step (2) is tetramethylethylenediamine.

[0146] Furthermore, the specific steps of step (2) are as follows:

[0147] Dissolve acrylamide in water, add the amino acid polymer crosslinker solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 9, then introduce nitrogen to remove dissolved oxygen in the mixed solution, add an initiator at 12°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0148] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0149] Furthermore, the drying process control conditions of the block gel after cutting are: 70° C., forced air drying for 5 hours.

[0150] Furthermore, the process control conditions of crushing are: crushing with a high-speed crusher at a rotation speed of 10000RPM for 40s.

[0151] Furthermore, the process control conditions of screening are: using a 100-mesh sieve and a 140-mesh sieve for screening to obtain a granular oil displacement agent with a particle size between 0.1 and 0.15 mm.

[0152] Furthermore, in step (2):

[0153] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is 2:0.03:0.02:60:200.

[0154] Furthermore, the water is deionized water.

[0155] The amino acid polymer cross-linked particle oil-displacing agent is prepared by the above preparation method.

[0156] The above-mentioned amino acid polymer cross-linked granular oil displacement agent is used as an oil displacement agent in tertiary oil recovery.

[0157] The above-mentioned amino acid polymer cross-linked particle oil displacement agent is used as a plugging agent in tertiary oil recovery.

[0158] Example 5

[0159] The preparation method of the particle oil displacement agent based on amino acid polymer cross-linking is as follows:

[0160] (1) preparing an amino acid polymer cross-linking agent solution;

[0161] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0162] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0163] One part of amino acid polymer and 3 parts of glycidyl methacrylate were dissolved in 96 parts of water to obtain a mixed solution, the pH value of the mixed solution was adjusted to 10 by using an alkaline substance, and a polymerization reaction was carried out at 60° C. for 6 hours to obtain an amino acid polymer crosslinker solution.

[0164] Furthermore, the alkaline substance is potassium hydroxide.

[0165] Furthermore, the amino acid polymer is polyaspartic acid.

[0166] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0167] The amino acid polymer cross-linking agent solution obtained in step (1) was poured into a dialysis bag with a molecular weight of 3000 and dialyzed in deionized water for 7 days.

[0168] Furthermore, the initiator in step (2) is potassium persulfate.

[0169] Furthermore, the promoter in step (2) is pentamethyldiethylenetriamine.

[0170] Furthermore, the specific steps of step (2) are as follows:

[0171] Dissolve acrylamide in water, add the amino acid polymer crosslinker solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 9, then introduce helium to remove dissolved oxygen in the mixed solution, add an initiator at 12°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0172] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0173] Furthermore, the drying process control conditions of the block gel after cutting are: 80° C., forced air drying for 4 hours.

[0174] Furthermore, the process control conditions of crushing are: crushing with a high-speed crusher at a rotation speed of 26000RPM for 15s.

[0175] Furthermore, the process control conditions of screening are: using a 100-mesh sieve and a 140-mesh sieve for screening to obtain a granular oil displacement agent with a particle size between 0.1 and 0.15 mm.

[0176] Furthermore, in step (2):

[0177] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is 2.5:0.03:0.02:60:140.

[0178] Furthermore, the water is deionized water.

[0179] The amino acid polymer cross-linked granular oil-displacing agent is prepared by any one of the above preparation methods.

[0180] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as an oil displacement agent in tertiary oil recovery.

[0181] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as a plugging agent in tertiary oil recovery.

[0182] Example 6

[0183] The preparation method of the particle oil displacement agent based on amino acid polymer cross-linking is as follows:

[0184] (1) preparing an amino acid polymer cross-linking agent solution;

[0185] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0186] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0187] One part of amino acid polymer and 6 parts of allyl glycidyl ether were dissolved in 93 parts of water to obtain a mixed solution, the pH value of the mixed solution was adjusted to 9.5 by using an alkaline substance, and a polymerization reaction was carried out at 60° C. for 6 hours to obtain an amino acid polymer crosslinker solution.

[0188] Furthermore, the alkaline substance is potassium hydroxide.

[0189] Furthermore, the amino acid polymer is polyaspartic acid.

[0190] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0191] The amino acid polymer cross-linking agent solution obtained in step (1) was poured into a dialysis bag with a molecular weight of 3000 and dialyzed in deionized water for 7 days.

[0192] Furthermore, the initiator in step (2) is potassium persulfate.

[0193] Furthermore, the promoter in step (2) is pentamethyldiethylenetriamine.

[0194] Furthermore, the specific steps of step (2) are as follows:

[0195] Dissolve acrylamide in water, add the amino acid polymer crosslinker solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 9, then introduce argon gas to remove dissolved oxygen in the mixed solution, add an initiator at 12°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0196] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0197] Furthermore, the drying process control conditions of the block gel after cutting are: 70° C., forced air drying for 5 hours.

[0198] Furthermore, the process control conditions of crushing are: crushing with a high-speed crusher at a rotation speed of 20000RPM for 25s.

[0199] Furthermore, the process control conditions of screening are: using a 100-mesh sieve and a 140-mesh sieve for screening to obtain a granular oil displacement agent with a particle size between 0.1 and 0.15 mm.

[0200] Furthermore, in step (2):

[0201] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is 3:0.03:0.02:60:280.

[0202] Furthermore, the water is deionized water.

[0203] The amino acid polymer cross-linked granular oil-displacing agent is prepared by any one of the above preparation methods.

[0204] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as an oil displacement agent in tertiary oil recovery.

[0205] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as a plugging agent in tertiary oil recovery.

[0206] Example 7

[0207] The preparation method of the particle oil displacement agent based on amino acid polymer cross-linking is as follows:

[0208] (1) preparing an amino acid polymer cross-linking agent solution;

[0209] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0210] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0211] 1 part of amino acid polymer and 12 parts of allyl glycidyl ether were dissolved in 87 parts of water to obtain a mixed solution, the pH value of the mixed solution was adjusted to 9 by alkaline substances, and a polymerization reaction was carried out at 80° C. for 4 hours to obtain an amino acid polymer crosslinker solution.

[0212] Furthermore, the alkaline substance is sodium hydroxide.

[0213] Furthermore, the amino acid polymer is polyaspartic acid.

[0214] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0215] The amino acid polymer cross-linking agent solution obtained in step (1) was poured into a dialysis bag with a molecular weight of 2000 and dialyzed in deionized water for 14 days.

[0216] Furthermore, the initiator in step (2) is potassium persulfate.

[0217] Furthermore, the promoter in step (2) is tetramethylethylenediamine.

[0218] Furthermore, the specific steps of step (2) are as follows:

[0219] Dissolve acrylamide in water, add the amino acid polymer cross-linking agent solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 9, then introduce neon gas to remove dissolved oxygen in the mixed solution, add an initiator at 12° C., and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0220] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0221] Furthermore, the drying process control conditions of the block gel after cutting are: 80° C., forced air drying for 4 hours.

[0222] Furthermore, the process control conditions of crushing are: crushing with a high-speed crusher at a speed of not less than 10000RPM for at least 15s.

[0223] Furthermore, the process control conditions of screening are: using a 100-mesh sieve and a 140-mesh sieve for screening to obtain a granular oil displacement agent with a particle size between 0.1 and 0.15 mm.

[0224] Furthermore, in step (2):

[0225] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is (0.5-3): (0.02-0.04): (0.02-0.04): (40-80): (140-280).

[0226] Furthermore, the water is deionized water.

[0227] The amino acid polymer cross-linked granular oil-displacing agent is prepared by any one of the above preparation methods.

[0228] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as an oil displacement agent in tertiary oil recovery.

[0229] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as a plugging agent in tertiary oil recovery.

[0230] Example 8

[0231] The preparation method of the particle oil displacement agent based on amino acid polymer cross-linking is as follows:

[0232] (1) preparing an amino acid polymer cross-linking agent solution;

[0233] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0234] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0235] One part of amino acid polymer and 3 parts of allyl glycidyl ether were dissolved in 96 parts of water to obtain a mixed solution, the pH value of the mixed solution was adjusted to 9 by an alkaline substance, and a polymerization reaction was carried out at 60° C. for 8 hours to obtain an amino acid polymer crosslinker solution.

[0236] Furthermore, the alkaline substance is potassium hydroxide.

[0237] Furthermore, the amino acid polymer is polysarcosine.

[0238] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0239] The amino acid polymer cross-linking agent solution obtained in step (1) was poured into a dialysis bag with a molecular weight of 3000 and dialyzed in deionized water for 7 days.

[0240] Furthermore, the initiator in step (2) is potassium persulfate.

[0241] Furthermore, the promoter in step (2) is tetramethylethylenediamine.

[0242] Furthermore, the specific steps of step (2) are as follows:

[0243] Dissolve acrylamide in water, add the amino acid polymer crosslinker solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 9, then introduce nitrogen to remove dissolved oxygen in the mixed solution, add an initiator at 12°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0244] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0245] Furthermore, the drying process control conditions of the block gel after cutting are: 80° C., forced air drying for 4 hours.

[0246] Furthermore, the process control conditions of crushing are: crushing with a high-speed crusher at a rotation speed of 10000RPM for 30s.

[0247] Furthermore, the process control conditions of screening are: using a 100-mesh sieve and a 140-mesh sieve for screening to obtain a granular oil displacement agent with a particle size between 0.1 and 0.15 mm.

[0248] Furthermore, in step (2):

[0249] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is 2.5:0.03:0.02:60:200.

[0250] Furthermore, the water is deionized water.

[0251] The amino acid polymer cross-linked granular oil-displacing agent is prepared by any one of the above preparation methods.

[0252] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as an oil displacement agent in tertiary oil recovery.

[0253] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as a plugging agent in tertiary oil recovery.

[0254] Example 9

[0255] The preparation method of the particle oil displacement agent based on amino acid polymer cross-linking is as follows:

[0256] (1) preparing an amino acid polymer cross-linking agent solution;

[0257] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0258] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0259] 1 part of amino acid polymer and 12 parts of allyl glycidyl ether were dissolved in 87 parts of water to obtain a mixed solution, the pH value of the mixed solution was adjusted to 9.5 by alkaline substances, and a polymerization reaction was carried out at 70° C. for 6 hours to obtain an amino acid polymer crosslinker solution.

[0260] Furthermore, the alkaline substance is sodium bicarbonate.

[0261] Furthermore, the amino acid polymer is polyglutamic acid.

[0262] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0263] The amino acid polymer cross-linking agent solution obtained in step (1) was poured into a dialysis bag with a molecular weight of 2000 and dialyzed in deionized water for 14 days.

[0264] Furthermore, the initiator in step (2) is ammonium persulfate.

[0265] Furthermore, the promoter in step (2) is tetramethylethylenediamine.

[0266] Furthermore, the specific steps of step (2) are as follows:

[0267] Dissolve acrylamide in water, add the amino acid polymer cross-linking agent solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 8.5, then introduce nitrogen to remove dissolved oxygen in the mixed solution, add an initiator at 12°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0268] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0269] Furthermore, the drying process control conditions of the block gel after cutting are: 80° C., forced air drying for 4 hours.

[0270] Furthermore, the process control conditions of crushing are: crushing with a high-speed crusher at a rotation speed of 20000RPM for 15s.

[0271] Furthermore, the process control conditions of screening are: using a 100-mesh sieve and a 140-mesh sieve for screening to obtain a granular oil displacement agent with a particle size between 0.1 and 0.15 mm.

[0272] Furthermore, in step (2):

[0273] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is 2.5:0.04:0.04:40:260.

[0274] Furthermore, the water is deionized water.

[0275] The amino acid polymer cross-linked granular oil-displacing agent is prepared by any one of the above preparation methods.

[0276] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as an oil displacement agent in tertiary oil recovery.

[0277] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as a plugging agent in tertiary oil recovery.

[0278] Example 10

[0279] The preparation method of the particle oil displacement agent based on amino acid polymer cross-linking is as follows:

[0280] (1) preparing an amino acid polymer cross-linking agent solution;

[0281] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0282] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0283] One part of amino acid polymer and 5 parts of allyl glycidyl ether were dissolved in 94 parts of water to obtain a mixed solution, the pH value of the mixed solution was adjusted to 10 by using an alkaline substance, and a polymerization reaction was carried out at 75° C. for 5 hours to obtain an amino acid polymer crosslinker solution.

[0284] Furthermore, the alkaline substance is sodium hydroxide.

[0285] Furthermore, the amino acid polymer is polyleucine.

[0286] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0287] The amino acid polymer cross-linking agent solution obtained in step (1) was poured into a dialysis bag with a molecular weight of 2500 and dialyzed in deionized water for 10 days.

[0288] Furthermore, the initiator in step (2) is sodium persulfate.

[0289] Furthermore, the promoter in step (2) is tetramethylethylenediamine.

[0290] Furthermore, the specific steps of step (2) are as follows:

[0291] Dissolve acrylamide in water, add the amino acid polymer crosslinker solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 8.5, then introduce nitrogen to remove dissolved oxygen in the mixed solution, add an initiator at 15°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0292] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0293] Furthermore, the drying process control conditions of the block gel after cutting are: 75° C., forced air drying for 4.5 hours.

[0294] Furthermore, the process control conditions of crushing are: crushing with a high-speed crusher at a rotation speed of 10000RPM for 15s.

[0295] Furthermore, the process control conditions of screening are: using a 100-mesh sieve and a 140-mesh sieve for screening to obtain a granular oil displacement agent with a particle size between 0.1 and 0.15 mm.

[0296] Furthermore, in step (2):

[0297] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is 2.5:0.03:0.04:40:140.

[0298] Furthermore, the water is deionized water.

[0299] The amino acid polymer cross-linked granular oil-displacing agent is prepared by any one of the above preparation methods.

[0300] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as an oil displacement agent in tertiary oil recovery.

[0301] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as a plugging agent in tertiary oil recovery.

[0302] Embodiment 11

[0303] The preparation method of the particle oil displacement agent based on amino acid polymer cross-linking is as follows:

[0304] (1) preparing an amino acid polymer cross-linking agent solution;

[0305] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0306] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0307] One part of amino acid polymer and 4 parts of allyl glycidyl ether were dissolved in 95 parts of water to obtain a mixed solution, the pH value of the mixed solution was adjusted to 9.5 by using an alkaline substance, and a polymerization reaction was carried out at 70° C. for 6 hours to obtain an amino acid polymer crosslinker solution.

[0308] Furthermore, the alkaline substance is sodium hydroxide.

[0309] Furthermore, the amino acid polymer is polyglutamic acid.

[0310] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0311] The amino acid polymer cross-linking agent solution obtained in step (1) was poured into a dialysis bag with a molecular weight of 2500 and dialyzed in deionized water for 10 days.

[0312] Furthermore, the initiator in step (2) is potassium persulfate.

[0313] Furthermore, the promoter in step (2) is tetramethylethylenediamine.

[0314] Furthermore, the specific steps of step (2) are as follows:

[0315] Dissolve acrylamide in water, add the amino acid polymer crosslinker solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 9, then introduce nitrogen to remove dissolved oxygen in the mixed solution, add an initiator at 18°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0316] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0317] Furthermore, the drying process control conditions of the block gel after cutting are: 70° C., forced air drying for 5 hours.

[0318] Furthermore, the process control conditions of crushing are: crushing with a high-speed crusher at a rotation speed of 10000RPM for 15s.

[0319] Furthermore, the process control conditions of screening are: using a 100-mesh sieve and a 140-mesh sieve for screening to obtain a granular oil displacement agent with a particle size between 0.1 and 0.15 mm.

[0320] Furthermore, in step (2):

[0321] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is 2.5:0.04:0.03:40:200.

[0322] Furthermore, the water is deionized water.

[0323] The amino acid polymer cross-linked granular oil-displacing agent is prepared by any one of the above preparation methods.

[0324] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as an oil displacement agent in tertiary oil recovery.

[0325] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as a plugging agent in tertiary oil recovery.

[0326] Example 12

[0327] The preparation method of the particle oil displacement agent based on amino acid polymer cross-linking is as follows:

[0328] (1) preparing an amino acid polymer cross-linking agent solution;

[0329] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0330] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0331] One part of amino acid polymer and 6 parts of allyl glycidyl ether were dissolved in 93 parts of water to obtain a mixed solution, the pH value of the mixed solution was adjusted to 10 by using an alkaline substance, and a polymerization reaction was carried out at 80° C. for 4 hours to obtain an amino acid polymer crosslinker solution.

[0332] Furthermore, the alkaline substance is sodium bicarbonate.

[0333] Furthermore, the amino acid polymer is polysarcosine.

[0334] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0335] The amino acid polymer cross-linking agent solution obtained in step (1) was poured into a dialysis bag with a molecular weight of 2500 and dialyzed in deionized water for 10 days.

[0336] Furthermore, the initiator in step (2) is ammonium persulfate.

[0337] Furthermore, the promoter in step (2) is tetramethylethylenediamine.

[0338] Furthermore, the specific steps of step (2) are as follows:

[0339] Dissolve acrylamide in water, add the amino acid polymer cross-linking agent solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 8.5, then introduce nitrogen to remove dissolved oxygen in the mixed solution, add an initiator at 12°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0340] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0341] Furthermore, the drying process control conditions of the block gel after cutting are: 80° C., forced air drying for 4 hours.

[0342] Furthermore, the process control condition of crushing is: crushing with a high-speed crusher at a rotation speed of 10000RPM for at least 15s.

[0343] Furthermore, the process control conditions of screening are: using a 100-mesh sieve and a 140-mesh sieve for screening to obtain a granular oil displacement agent with a particle size between 0.1 and 0.15 mm.

[0344] Furthermore, in step (2):

[0345] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is 2.5:0.03:0.04:80:160.

[0346] Furthermore, the water is deionized water.

[0347] The amino acid polymer cross-linked granular oil-displacing agent is prepared by any one of the above preparation methods.

[0348] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as an oil displacement agent in tertiary oil recovery.

[0349] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as a plugging agent in tertiary oil recovery.

[0350] Example 13

[0351] The preparation method of the particle oil displacement agent based on amino acid polymer cross-linking is as follows:

[0352] (1) preparing an amino acid polymer cross-linking agent solution;

[0353] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0354] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0355] 1 part of amino acid polymer and 12 parts of allyl glycidyl ether were dissolved in 87 parts of water to obtain a mixed solution, the pH value of the mixed solution was adjusted to 9 by alkaline substances, and a polymerization reaction was carried out at 60° C. for 10 hours to obtain an amino acid polymer crosslinker solution.

[0356] Furthermore, the alkaline substance is sodium hydroxide.

[0357] Furthermore, the amino acid polymer is polyglutamic acid.

[0358] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0359] The amino acid polymer cross-linking agent solution obtained in step (1) was poured into a dialysis bag with a molecular weight of 2500 and dialyzed in deionized water for 10 days.

[0360] Furthermore, the initiator in step (2) is ammonium persulfate.

[0361] Furthermore, the promoter in step (2) is tetramethylethylenediamine.

[0362] Furthermore, the specific steps of step (2) are as follows:

[0363] Dissolve acrylamide in water, add the amino acid polymer cross-linking agent solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 8.5, then introduce nitrogen to remove dissolved oxygen in the mixed solution, add an initiator at 12°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0364] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0365] Furthermore, the drying process control conditions of the block gel after cutting are: 70° C., forced air drying for 5 hours.

[0366] Furthermore, the process control conditions of crushing are: crushing with a high-speed crusher at a rotation speed of 10000RPM for 15s.

[0367] Furthermore, the process control conditions of screening are: using a 100-mesh sieve and a 140-mesh sieve for screening to obtain a granular oil displacement agent with a particle size between 0.1 and 0.15 mm.

[0368] Furthermore, in step (2):

[0369] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is 0.5:0.02:0.02:40:140.

[0370] Furthermore, the water is deionized water.

[0371] The amino acid polymer cross-linked granular oil-displacing agent is prepared by any one of the above preparation methods.

[0372] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as an oil displacement agent in tertiary oil recovery.

[0373] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as a plugging agent in tertiary oil recovery.

[0374] Embodiment 14

[0375] The preparation method of the particle oil displacement agent based on amino acid polymer cross-linking is as follows:

[0376] (1) preparing an amino acid polymer cross-linking agent solution;

[0377] (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

[0378] Furthermore, in parts by mass, the specific steps of step (1) are as follows:

[0379] 1 part of amino acid polymer and 10 parts of allyl glycidyl ether were dissolved in 89 parts of water to obtain a mixed solution, the pH value of the mixed solution was adjusted to 10 by alkaline substances, and a polymerization reaction was carried out at 65° C. for 5 hours to obtain an amino acid polymer crosslinker solution.

[0380] Furthermore, the alkaline substance is sodium hydroxide.

[0381] Furthermore, the amino acid polymer is polysarcosine.

[0382] Furthermore, the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated before entering step (2). The specific steps of the pretreatment are as follows:

[0383] The amino acid polymer cross-linking agent solution obtained in step (1) was poured into a dialysis bag with a molecular weight of 2500 and dialyzed in dedistilled water for 10 days.

[0384] Furthermore, the initiator in step (2) is sodium persulfate.

[0385] Furthermore, the promoter in step (2) is tetramethylethylenediamine.

[0386] Furthermore, the specific steps of step (2) are as follows:

[0387] Dissolve acrylamide in water, add the amino acid polymer crosslinker solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 9, then introduce nitrogen to remove dissolved oxygen in the mixed solution, add an initiator at 18°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

[0388] Furthermore, the specific steps of the post-processing are: chopping, drying, crushing and screening the block gel.

[0389] Furthermore, the drying process control conditions of the block gel after cutting are: 80° C., forced air drying for 4 hours.

[0390] Furthermore, the process control conditions of crushing are: crushing with a high-speed crusher at a rotation speed of 26000RPM for 15s.

[0391] Furthermore, the process control conditions of screening are: using a 100-mesh sieve and a 140-mesh sieve for screening to obtain a granular oil displacement agent with a particle size between 0.1 and 0.15 mm.

[0392] Furthermore, in step (2):

[0393] The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is 3:0.04:0.04:80:280.

[0394] Furthermore, the water is distilled water.

[0395] The amino acid polymer cross-linked granular oil-displacing agent is prepared by any one of the above preparation methods.

[0396] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as an oil displacement agent in tertiary oil recovery.

[0397] The use of any of the above amino acid polymer cross-linked particulate oil displacement agents as a plugging agent in tertiary oil recovery.

[0398] Embodiment 15

[0399] The amino acid polymer cross-linked particle oil-displacing agent comprises a structural unit A, a structural unit B and a structural unit C, wherein:

[0400] The structural unit A is derived from an amino acid polymer;

[0401] The structural unit B is derived from allyl glycidyl ether;

[0402] The structural unit C is derived from acrylamide;

[0403] Based on the weight of the amino acid polymer cross-linked particulate oil-displacing agent, the content of the structural unit A is 0.0014% by weight, the content of the structural unit B is 0.0675% by weight, and the balance is the structural unit C.

[0404] Furthermore, the amino acid polymer is polylysine.

[0405] Furthermore, the particle size of the amino acid polymer cross-linked granular oil displacement agent is between 20 meshes and 200 meshes.

[0406] In another embodiment, the particle size of the amino acid polymer cross-linked particulate oil displacing agent is preferably between 100 mesh and 140 mesh.

[0407] Example 16

[0408] The amino acid polymer cross-linked particle oil-displacing agent comprises a structural unit A, a structural unit B and a structural unit C, wherein:

[0409] The structural unit A is derived from an amino acid polymer;

[0410] The structural unit B is derived from glycidyl methacrylate;

[0411] The structural unit C is derived from acrylamide;

[0412] Based on the weight of the amino acid polymer cross-linked particulate oil-displacing agent, the content of the structural unit A is 0.0225% by weight, the content of the structural unit B is 0.0173% by weight, and the balance is the structural unit C.

[0413] Furthermore, the amino acid polymer is polyaspartic acid.

[0414] Furthermore, the particle size of the amino acid polymer cross-linked granular oil displacement agent is between 20 meshes and 200 meshes.

[0415] In another embodiment, the particle size of the amino acid polymer cross-linked particulate oil displacing agent is preferably between 100 mesh and 140 mesh.

[0416] Embodiment 17

[0417] The amino acid polymer cross-linked particle oil-displacing agent comprises a structural unit A, a structural unit B and a structural unit C, wherein:

[0418] The structural unit A is derived from an amino acid polymer;

[0419] The structural unit B is derived from allyl glycidyl ether;

[0420] The structural unit C is derived from acrylamide;

[0421] Based on the weight of the amino acid polymer cross-linked particulate oil-displacing agent, the content of the structural unit A is 0.0016% by weight, the content of the structural unit B is 0.020% by weight, and the balance is the structural unit C.

[0422] Furthermore, the amino acid polymer is polysarcosine.

[0423] Furthermore, the particle size of the amino acid polymer cross-linked granular oil displacement agent is between 20 meshes and 200 meshes.

[0424] In another embodiment, the particle size of the amino acid polymer cross-linked particulate oil displacing agent is preferably between 100 mesh and 140 mesh.

[0425] Embodiment 18

[0426] The amino acid polymer cross-linked particle oil-displacing agent comprises a structural unit A, a structural unit B and a structural unit C, wherein:

[0427] The structural unit A is derived from an amino acid polymer;

[0428] The structural unit B is derived from glycidyl methacrylate;

[0429] The structural unit C is derived from acrylamide;

[0430] Based on the weight of the amino acid polymer cross-linked particle oil-displacing agent, the content of the structural unit A is 0.0015% by weight, the content of the structural unit B is 0.05% by weight, and the balance is the structural unit C.

[0431] Furthermore, the amino acid polymer is polyglutamic acid.

[0432] In another embodiment, the amino acid polymer is polyleucine.

[0433] Furthermore, the particle size of the amino acid polymer cross-linked granular oil displacement agent is between 20 meshes and 200 meshes.

[0434] In another embodiment, the particle size of the amino acid polymer cross-linked particulate oil displacing agent is preferably between 100 mesh and 140 mesh.

[0435] Figure 2 This is the infrared absorption spectrum of the amino acid polymer crosslinker solution prepared in Example 2 after post-treatment and sample preparation. Figure 2 It can be seen that the amino acid polymer crosslinker has an obvious vinyl absorption peak in the infrared spectrum: the crosslinker is at 3080.0cm -1 The absorption peak appears at 1647.0 cm, which is consistent with the stretching vibration of =CH. The stretching vibration peak of the C=C double bond is at 1647.0 cm -1 In addition, the amino acid polymer crosslinker is observed at 1001.3 cm -1 and 926.5cm-1 The absorption peak at corresponds to the =CH bending vibration. Based on the above analysis, it can be concluded that there are double bonds in the crosslinker, which shows that the modification is successful and the allyl glycidyl ether molecules are indeed grafted onto the polylysine molecular chain. Combining the above information, it is proved that double bonds are successfully introduced into polylysine. The successful preparation of the crosslinker can be seen from the position change of the absorption peak of the infrared spectrum and the characteristic peak absorption of important functional groups.

[0436] The particle oil displacement agent samples prepared in Examples 1-14 were tested for the following related properties according to the following methods:

[0437] 1. Rheological properties test

[0438] The rheological properties were tested using TA's AR2000 EX torque rheometer. The test included time scanning and steady-state shear experiments. First, the particle oil displacement agent sample to be tested was evenly dispersed in salt water to prepare a sample concentration of 5000 mg / L and a mineralization of 30000 mg / L (Ca 2+ ,Mg 2+ ≥2000mg / L) of the test solution. The time scan was performed at a single frequency, with a frequency of f = 1Hz, and the average value of the five test results at a stress of τ = 0.1Pa was the modulus G' of the solution. The test temperature was 25°C. The steady-state shear experiment used a time scan at a single shear rate, and the average value of the five tests was also taken as the viscosity of the solution. The shear rate v = 7.34s -1 , the test temperature is 85°C. The brine used in the experiment is simulated water prepared according to the mineralization degree and salt ion concentration of different oil reservoirs in Shengli Oilfield. The specific brine formula is shown in Table 1.

[0439] Table 1. Formulas of brine with different mineralization degrees

[0440] Mineralization <![CDATA[H2O]]> NaCl <![CDATA[CaCl2]]> <![CDATA[MgCl2·6H2O]]> <![CDATA[Na2SO4]]> 30000mg / L 1000mL 27.3067g 1.11g 3.833g 0

[0441] The rheological properties test data are shown in Table 2.

[0442] Table 2 Rheological properties test results

[0443]

[0444]

[0445] As can be seen from Table 2, the amino acid polymer cross-linked particle oil displacement agents prepared in Examples 1-14 have both elasticity and viscosity, and the modulus and viscosity are adjustable in a wide range, which can well meet the needs of different oil reservoirs.

[0446] Figure 3 and Figure 4The frequency scanning diagram of the prepared hydrogel is given, and the test conditions are in the frequency scanning mode, the frequency sweep range is 0.01-100 Hz, and the amplitude γ0 = 0.05. It can be seen from the figure that the amino acid polymer cross-linked particle oil displacement agent prepared in Examples 1-4 has a strong frequency dependence and a high loss angle, indicating that it has a strong viscoelasticity.

[0447] 2. Mechanical properties test

[0448] The mechanical properties of the block gel samples prepared in Examples 1-8 were characterized using a universal tensile machine (Instron 5567), and the prepared block gel samples were directly tested.

[0449] Stress-strain curve test: In tensile mode, the block sample was cut into a dumbbell shape (length 20 mm, width 4 mm, thickness 1 mm). The edge of the gel was clamped with a pneumatic clamp and stretched until the sample broke. The stretching rate was controlled to 100 mm / min. Similarly, each sample was repeated 5 times.

[0450] Test results such as Figure 5 , Figure 6 As shown in the figure, it can be seen that the fracture strain of the block gel prepared in Example 1 is as high as 3300%, and the fracture strength of the block gel prepared in Example 4 is as high as 0.65 MPa.

[0451] 3. Plugging performance test

[0452] The plugging performance test of the amino acid polymer cross-linked granular oil-displacing agent prepared in Example 3 was performed. Weigh 0.4 g of the amino acid polymer cross-linked granular oil-displacing agent prepared in Example 3 and add it to a beaker of salt water with a salinity of 30000 mg / L. After uniform dispersion for 2 hours under magnetic stirring, an oil-displacing agent suspension was obtained. Before the experiment, quartz sand of a certain mesh size was selected and mixed evenly and loaded into a sand-filled tube to test the water permeability before and after the sand-filled tube was plugged. After the quartz sand of different mesh sizes was mixed evenly and filled into a steel pipe and sealed, a sand-filled tube with a certain permeability was made. The pressure of water passing through the sand-filled tube before and after the injection of the oil-displacing agent was recorded respectively. The water permeability of the sand-filled tube before and after plugging was calculated by the permeability formula, which was recorded as K1 and K2. After that, the water phase plugging rate η of the material can be obtained according to the formula η=(K1-K2) / K1, thereby quantitatively evaluating the plugging performance of G-PPG. The results are shown in Table 3.

[0453] Table 3 Effect of oil displacement agent concentration on plugging rate

[0454] 5％ 7.5％ 10％ <![CDATA[K1]]> 0.353571 0.353571 0.353571 <![CDATA[K2]]> 0.044444 0.032776 0.018138 η 87.43％ 90.73％ 94.87％

[0455] As shown in Table 3, different concentrations of amino acid polymer cross-linked particle oil displacement agents all showed good plugging effects, which were derived from the good water absorption and expansion ability of the gel particles, and their plugging rates were all above 87%. With the increase of gel particle concentration, the reduction in the water phase permeability of the sand-filled pipe after the plugging agent was injected increased significantly, and the plugging effect of the oil displacement agent on water was also better.

[0456] 4. Oil displacement performance test

[0457] The double-tube model with sand filling (low permeability tube permeability k1 = 1000 × 10 -3 μm 2 , high permeability tube permeability k2=3000×10 -3 μm 2 ) The oil displacement performance of the amino acid polymer cross-linked granular oil displacement agent prepared in Example 3 was tested.

[0458] The test temperature is 85℃ and the injection water mineralization is 30000mg / L. On the basis of saturated water, saturated simulated oil (crude oil viscosity 100mPa.s) was used for aging for 24h, and the oil displacement test was carried out. First, water was driven to 98% water content in the produced fluid, and then the oil displacement agent suspension was injected. 70mL of the suspension was injected, and then water was driven to more than 98% to end the test. The test results are as follows Figure 7 As shown in the figure, it can be seen that the final recovery rate of the oil flooding experiment is 71.7%, and the recovery rate is further increased by 28.2% after water flooding.

[0459] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A particle oil displacement agent based on amino acid polymer cross-linking, characterized in that: The amino acid polymer cross-linked particle oil displacement agent comprises a structural unit A, a structural unit B and a structural unit C, wherein: The structural unit A is derived from an amino acid polymer; The structural unit B is derived from allyl glycidyl ether or glycidyl methacrylate; The structural unit C is derived from acrylamide; Based on the weight of the amino acid polymer cross-linked particulate oil-displacing agent, the content of the structural unit A is 0.0014 wt %-0.0225 wt %, the content of the structural unit B is 0.0173 wt %-0.0675 wt %, and the content of the structural unit C is 99.3073 wt %-99.9813 wt %.

2. The amino acid polymer cross-linked particle oil-displacing agent according to claim 1, characterized in that: The amino acid polymer is one of polylysine, polyaspartic acid, polysarcosine, polyglutamic acid and polyleucine.

3. The amino acid polymer cross-linked particle oil displacing agent according to claim 1, characterized in that: The particle size of the amino acid polymer cross-linked particulate oil displacing agent is between 20 meshes and 200 meshes, preferably between 100 meshes and 140 meshes.

4. The method for preparing the amino acid polymer cross-linked particle oil displacement agent according to any one of claims 1 to 3, characterized in that: The specific steps are as follows: (1) preparing an amino acid polymer cross-linking agent solution; (2) In the presence of an initiator, a promoter and water as a solvent, the amino acid polymer crosslinking agent solution obtained in step (1) and acrylamide are polymerized, and after the reaction is completed, a particulate oil displacement agent based on amino acid polymer crosslinking is obtained by post-treatment.

5. The method for preparing the amino acid polymer cross-linked particle oil-displacing agent according to claim 4, characterized in that: In parts by mass, the specific steps of step (1) are as follows: One part of amino acid polymer and 3-12 parts of allyl glycidyl ether or glycidyl methacrylate are dissolved in 87-96 parts of water to obtain a mixed solution, the pH value of the mixed solution is adjusted to 9-10 by alkaline substances, and a polymerization reaction is carried out at 60-80° C. for at least 4 hours to obtain an amino acid polymer crosslinker solution.

6. The method for preparing the amino acid polymer cross-linked particle oil-displacing agent according to claim 5, characterized in that: The alkaline substance is one of sodium hydroxide, potassium hydroxide and sodium bicarbonate.

7. The method for preparing the amino acid polymer cross-linked particle oil-displacing agent according to claim 5, characterized in that: After the amino acid polymer cross-linking agent solution obtained in step (1) is pretreated, the step (2) is then performed. The specific steps of the pretreatment are as follows: The amino acid polymer cross-linking agent solution obtained in step (1) is poured into a dialysis bag with a molecular weight of no more than 3000, and dialyzed in deionized water or distilled water for at least 7 days.

8. The method for preparing the amino acid polymer cross-linked particle oil-displacing agent according to claim 4, characterized in that: The initiator in step (2) is one of potassium persulfate, ammonium persulfate and sodium persulfate.

9. The method for preparing the amino acid polymer cross-linked particle oil-displacing agent according to claim 4, characterized in that: The accelerator in step (2) is tetramethylethylenediamine or pentamethyldiethylenetriamine.

10. The method for preparing the amino acid polymer cross-linked particle oil displacement agent according to claim 4, characterized in that: The specific steps of step (2) are as follows: Dissolve acrylamide in water, add the amino acid polymer crosslinker solution prepared in step (1) and the accelerator thereto to obtain a mixed solution, adjust the pH value of the mixed solution to 8.5-9, then introduce nitrogen or inert gas to remove dissolved oxygen in the mixed solution, add an initiator at 12-18°C, and perform an adiabatic polymerization reaction. After the reaction is completed, a block gel is obtained, which is then post-treated to obtain a granular oil displacement agent.

11. The method for preparing the amino acid polymer cross-linked particle oil displacement agent according to claim 8, characterized in that: The specific steps of the post-treatment are: chopping, drying, crushing and screening the block gel.

12. The method for preparing the amino acid polymer cross-linked particle oil displacement agent according to claim 11, characterized in that: The drying process control conditions of the block gel after cutting are: 70-80° C., forced air drying for 4-5 hours.

13. The method for preparing the amino acid polymer cross-linked particle oil displacement agent according to claim 11, characterized in that: The process control conditions for crushing are: crushing with a high-speed crusher at a speed of not less than 10000RPM for at least 15s.

14. The method for preparing the amino acid polymer cross-linked particle oil displacement agent according to claim 11, characterized in that: The process control conditions for screening are: using a 20-mesh screen and a 200-mesh screen to screen to obtain a particle oil displacement agent with a particle size between 20 and 200 meshes, preferably The granular oil displacement agent with a particle size between 0.1 and 0.15 mm was obtained by sieving with a 100-mesh sieve and a 140-mesh sieve.

15. The method for preparing the amino acid polymer cross-linked particle oil displacement agent according to claim 4, characterized in that: In step (2): The mass ratio of the amino acid polymer cross-linking agent solution, initiator, accelerator, acrylamide and water obtained in step (1) is (0.5-3): (0.02-0.04): (0.02-0.04): (40-80): (140-280).

16. The method for preparing the amino acid polymer cross-linked particle oil displacement agent according to claim 4, characterized in that: The water is one of deionized water and distilled water.

17. A particle oil displacement agent based on amino acid polymer cross-linking, characterized in that: It is prepared by the preparation method described in any one of claims 4 to 16.

18. Use of the amino acid polymer cross-linked granular oil displacement agent according to any one of claims 1 to 3 and 17 as an oil displacement agent in tertiary oil recovery.

19. Use of the amino acid polymer cross-linked particle oil displacement agent according to any one of claims 1 to 3 and 17 as a plugging agent in tertiary oil recovery.

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