Nano imbibition oil-displacing agent as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of oilfield chemistry, and provides a nano imbibition oil-displacing agent as well as a preparation method and application thereof. The nano imbibition oil displacement agent is obtained by carrying out polymerization reaction on an acrylamide monomer and a surfactant; the acrylamide monomer is prepared from at least one of acrylamide, 2-acrylamido-2-methylpropanesulfonic acid, N-dodecyl acrylamide and 4-acryloyl morpholine, and the acrylamide monomer is prepared from at least one of acrylamide, 2-acrylamido-2-methylpropanesulfonic acid, N-dodecyl acrylamide and 4-acryloyl morpholine; the surfactant comprises at least one of alpha-alkenyl sulfonate, alkylphenol polyoxyethylene ether and lauryl sodium sulfate. The nanometer imbibition oil-displacing agent solution can strengthen the spontaneous imbibition effect in the fracturing process, improve the shale oil reservoir imbibition recovery ratio and guarantee stable production and yield increase of shale oil development.

Description

Technical Field

[0001] The invention belongs to the technical field of oilfield chemistry and relates to a nano-imbibition oil-displacing agent and a preparation method and application thereof. Background Art

[0002] The shale oil reservoir structure is complex, with strong rock matrix heterogeneity, low porosity (4.5%-11%), ultra-low permeability ((0.001-0.1)×10 -3 μm 2 ) and multiple micron-nano pore throats, horizontal well hydraulic fracturing is often used for development. During the fracturing and well soaking stage, spontaneous imbibition is an important mechanism for shale oil development. In view of the complex pore structure of shale oil reservoirs, how to strengthen the spontaneous imbibition of shale reservoirs and improve the effective utilization of shale oil has important guiding significance for the high and stable production of shale oil.

[0003] The imbibition of shale reservoirs is affected by many factors such as reservoir wettability, permeability, pore characteristics, and crude oil fluidity. In order to effectively enhance the imbibition of reservoirs, it is necessary to develop suitable imbibition agents to change the oil wettability caused by the self-generation and self-storage of shale reservoirs, provide a moderately small interfacial tension, increase capillary force, and improve the power of imbibition oil displacement. At the same time, the porosity and permeability of shale oil reservoirs are poor, and it is also necessary to consider whether the injected fluid can pass through the micro-nano pores of the reservoir.

[0004] Currently, the commonly used fracturing imbibition aids are single or compound surfactants, which can significantly reduce interfacial tension, easily lead to oil-water emulsification, affect the size of capillary force, and will be adsorbed in large quantities on the rock surface, but have little effect on the change of oil-water mobility ratio, resulting in low modifier sweep efficiency.

[0005] Chinese invention patent application CN113717709A discloses a nanofluid imbibing agent, which is mainly composed of amphiphilic grafted modified nano silica particles, betaine type surfactant and nonionic surfactant, and has good salt resistance and compatibility with fracturing fluid.

[0006] Chinese invention patent application CN113943411A discloses an imbibition oil displacement agent, which is mainly obtained by compounding a double-bond modified nanomaterial, acrylamide monomers, a nanomaterial synthesized from sodium tetradecene α-olefin sulfonate, and a polyoxyethylene ether nonionic surfactant.

[0007] In the above two nano-imbibition oil displacement agents, there is no chemical bond between the nano-materials and the surfactants, and the interaction is weak. During the formation migration process, the interaction is easily destroyed, resulting in the agglomeration of the nano-materials, which affects the imbibition recovery rate.

[0008] Chinese invention patent CN113265022B discloses an imbibition oil displacement agent and a preparation method thereof, wherein the imbibition oil displacement agent is prepared from a polymer emulsion and a surfactant solution at a mass ratio of 1.5-9:1, wherein a surface-active water-soluble polymer emulsion is mixed with a surfactant solution, and the nonionic surfactant component in the surfactant solution is loaded on a water-soluble polymer skeleton to ensure that the entire system functions in a high-salt environment, and the mixing ratio of the two is appropriate, so that the oil displacement efficiency of the entire oil displacement agent system reaches more than 10%. The imbibition oil displacement agent requires an emulsifier to improve the compatibility of the polymerization system during its preparation, and is not suitable for shale oil reservoirs with complex structures and ultra-low permeability.

[0009] Therefore, targeting the complex pore structure of shale oil reservoirs, comprehensively considering many factors such as reservoir wettability, permeability, pore characteristics, crude oil fluidity, etc., to develop suitable imbibition agents to effectively enhance the spontaneous imbibition of shale reservoirs is the key to the current high and stable production of shale oil. Summary of the invention

[0010] In view of the problems that the prior art lacks an imbibition oil-displacing agent suitable for shale oil reservoir fracturing, and that the interaction ability between nanomaterials and surfactants in the existing shale oil reservoir fracturing imbibition oil-displacing agents is weak and agglomeration is easy to occur, the present invention provides a nano imbibition oil-displacing agent and a preparation method and application thereof. Acrylamide is used as a skeleton structure (which may also be supplemented with other acrylamide monomers) and polymerized with a surfactant to obtain the nano imbibition oil-displacing agent. Under the compounding action of the acrylamide monomer and the surfactant, the imbibition oil-displacing agent has an excellent spontaneous imbibition effect, can be injected into the micro-nano pore throats of the shale oil reservoir, and effectively improves the imbibition recovery rate of the shale oil reservoir.

[0011] One of the technical solutions of the present invention is:

[0012] Provided is a nano-infiltration oil-displacing agent, which is obtained by polymerization reaction of acrylamide monomers and surfactants; the acrylamide monomers include at least one of acrylamide, 2-acrylamido-2-methylpropanesulfonic acid, N-dodecyl acrylamide and 4-acryloylmorpholine; the surfactant includes at least one of α-olefin sulfonate, alkylphenol polyoxyethylene ether and sodium dodecyl sulfate.

[0013] Preferably, the acrylamide monomer includes at least acrylamide, and the surfactant is α-olefin sulfonate.

[0014] In some embodiments of the present invention, when there is only one acrylamide monomer, acrylamide is selected, that is, acrylamide is used as the skeleton structure.

[0015] In some embodiments of the present invention, the acrylamide monomers are acrylamide and 2-acrylamido-2-methylpropanesulfonic acid.

[0016] In some embodiments of the present invention, the acrylamide monomers are acrylamide and N-dodecyl acrylamide.

[0017] In some embodiments of the present invention, the acrylamide monomers are acrylamide and 4-acryloylmorpholine.

[0018] More preferably, the amount of the acrylamide monomers is: 10-30 wt % of acrylamide, 0-15 wt % of 2-acrylamido-2-methylpropanesulfonic acid, 0-10 wt % of N-dodecyl acrylamide and 0-10 wt % of 4-acryloylmorpholine.

[0019] Preferably, the surfactant is used in an amount of 5-20 wt%.

[0020] More preferably, the α-olefin sulfonate is sodium α-olefin sulfonate.

[0021] In some embodiments of the present invention, the general structural formula of the nano-infiltration oil displacement agent is as follows:

[0022]

[0023] Wherein, R is a C11-13 alkyl group; M is any one of Na and K; x:y:z:m:n=2-8:0-5:1-5:0-5:0-5.

[0024] Furthermore, the particle size of the nano-imbibition oil-displacing agent is 1-100 nm.

[0025] The second technical solution of the present invention is:

[0026] A method for preparing the nano-imbibition oil-displacing agent is provided, comprising the following steps:

[0027] (1) adding acrylamide monomers and surfactants into a reaction device;

[0028] (2) Under nitrogen protection, add water to fully dissolve and adjust the pH;

[0029] (3) Raise the temperature, add an initiator, and carry out a polymerization reaction to obtain the product.

[0030] Furthermore, the amount of the initiator used accounts for 0.08-1.0 wt % of the total amount of the acrylamide monomer and the surfactant.

[0031] Furthermore, the initiator includes an oxidant and a reductant; the mass ratio of the oxidant to the reductant is 1:0.7-0.8.

[0032] Furthermore, the oxidant is selected from at least one of ammonium persulfate, sodium persulfate and potassium persulfate; and the reducing agent is selected from sodium sulfite or sodium bisulfite.

[0033] Furthermore, in step (2), the pH value is 6.0-8.0.

[0034] Furthermore, in step (3), the polymerization reaction temperature is 50-70°C; and the polymerization time is 3-5h.

[0035] The third technical solution of the present invention is:

[0036] Provided is a nano-imbibition oil-displacing agent solution, which comprises the nano-imbibition oil-displacing agent or the nano-imbibition oil-displacing agent prepared by the above-mentioned preparation method.

[0037] Furthermore, the solvent of the solution is deionized water or formation water.

[0038] Furthermore, the concentration of the nano-imbibition oil-displacing agent in the nano-imbibition oil-displacing agent solution is 0.1-2.0 wt %.

[0039] The fourth technical solution of the present invention is:

[0040] Provided is the use of the nano-imbibition oil-displacing agent or the nano-imbibition oil-displacing agent solution in shale oil reservoir fracturing displacement.

[0041] Furthermore, the shale oil reservoir has a formation temperature of ≤100°C, a formation water salinity of 0-10000 mg / L, and a permeability of (0.01-1.0)×10 -3 μm 2 .

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

[0043] (1) The nano-infiltration oil-displacing agent of the present invention is a combination of acrylamide monomer as a skeleton structure and a surfactant to obtain a nano-infiltration oil-displacing agent with a low concentration. When it is combined with a water phase with a salinity of 0-10000 mg / L, it can effectively reduce the interfacial tension of the nano-infiltration oil-displacing agent solution (interfacial tension ≤ 0.07 mN·m -1) and contact angle (≤33.66°), can reduce the starting pressure capacity of oil-water interfacial tension, can increase capillary force, improve spreading coefficient, improve the power of imbibition oil displacement and the degree of stripping of crude oil on the core surface; the nano-imbibition oil displacement agent can also improve the adhesion work reduction rate and spontaneous imbibition recovery rate, and its adhesion work reduction rate is ≥98%, and the imbibition efficiency is ≥30.34%; it can also effectively avoid the adsorption and chromatographic separation problems of the imbibition oil displacement agent on the rock surface during the migration of the formation; the bimolecular adsorption of the nano-imbibition oil displacement agent on the rock surface can change the oil wettability caused by the self-generation and self-storage of the shale reservoir, thereby reducing the adhesion work of shale oil and mobilizing the large, medium and small pore residual oil in the shale reservoir, and strengthening the spontaneous imbibition oil displacement effect;

[0044] (2) When other acrylamide monomers are further combined with the acrylamide backbone structure, and the dosage ratio of the acrylamide monomers and the surfactant is further optimized, a polymer having a specific structural unit and polymerization degree ratio is obtained, thereby further improving its comprehensive oil recovery performance;

[0045] (3) The nano-imbibition oil displacement agent of the present invention can be dispersed to form a nano-scale solution with a particle size of only 1-10 nm, which can penetrate into the small and complex pore throats of the shale reservoir to displace crude oil, increase the sweep degree, and enhance the spontaneous imbibition effect;

[0046] (4) The nano-imbibition oil displacement agent solution of the present invention is used for energy-enhanced fracturing. The artificial fractures formed by fracturing enter the micro-fractures of the reservoir matrix, and the spontaneous imbibition effect is strengthened in the later well soaking process, thereby improving the imbibition recovery rate of the shale oil reservoir and ensuring the stable production and increased production of shale oil development;

[0047] (5) The method for preparing the nano-absorption oil displacement agent provided by the present invention has a high monomer conversion rate and a simple preparation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 The particle size distribution of nano-imbibition oil-displacing agent solutions SXY-1, SXY-7 and SXY-8 of the nano-imbibition oil-displacing agent prepared in Example 1, Comparative Example 3 and Comparative Example 4 with a concentration of 0.3wt.%;

[0049] Figure 2 The interfacial tension diagrams of 0.3wt.% nano-imbibition oil displacement agent solutions SXY-1, SXY-7 and SXY-8 of Example 1, Comparative Example 3 and Comparative Example 4;

[0050] Figure 3 The spontaneous imbibition recovery results of the nano-imbibition oil displacement agent solutions SXY-1 to SXY-4, surfactant AOS and water in shale oil reservoirs prepared in Examples 5-8 of the present invention;

[0051] Figure 4The spontaneous imbibition recovery results of the nano-imbibition oil-displacing agent solutions SXY-7 and SXY-8 prepared in Comparative Examples 3 and 4 of the present invention in shale oil reservoirs. DETAILED DESCRIPTION

[0052] The following non-limiting examples can enable those skilled in the art to more fully understand the present invention, but do not limit the present invention in any way. The following content is merely an exemplary description of the scope of the present invention, and those skilled in the art can make various changes and modifications to the present invention based on the disclosed content, which should also fall within the scope of the present invention.

[0053] The chemical formula of the main component of surfactant AOS: C 14 H 27 SO3Na, the structural formula is as follows:

[0054]

[0055] Example 1

[0056] Preparation of Nano-absorption Oil Displacement Agent SX-1:

[0057] (1) 15 g acrylamide, 10 g 2-acrylamido-2-methylpropanesulfonic acid and 5 g surfactant AOS were placed in a 250 mL round-bottom flask with a mechanical stirrer, and nitrogen was continuously passed to maintain an inert environment;

[0058] (2) adding 70 g of deionized water to the flask to maintain the total monomer (including acrylamide monomer and surfactant) concentration of the solution at 30 wt %, and setting the stirring speed to 500 rpm; after the monomer is completely stirred and dissolved, adjusting the pH of the system to neutral with an aqueous sodium hydroxide solution;

[0059] (3) After the system was heated to 50°C, 0.011 g of Na2SO3 and 0.013 g of Na2S2O8 (accounting for 0.08 wt% of the total mass fraction of the monomer) were added as initiators; after reacting at 50°C for 5 h, the mixture was cooled to 25°C to obtain a light yellow, oily and thick liquid;

[0060] (4) 10 mL of NaOH / Na2CO3 solution (NaOH / Na2CO3 mass ratio = 1:1) was added to the liquid, washed with ethanol, dried, and crushed to obtain the final product, nano-infiltration oil displacement agent SX-1.

[0061] Example 2

[0062] The preparation method is the same as that of Example 1, except that in step (1), 15 g acrylamide monomer, 10 g 4-acryloylmorpholine and 5 g surfactant AOS are added to prepare nano-absorption oil displacement agent SX-2.

[0063] Example 3

[0064] The preparation method is the same as that of Example 1, except that in step (1), 15 g acrylamide monomer, 10 g N-dodecyl acrylamide and 5 g surfactant AOS are added to prepare nano-absorption oil displacement agent SX-3.

[0065] Example 4

[0066] The preparation method is the same as that of Example 1, except that in step (1), 15 g acrylamide, 5 g 2-acrylamido-2-methylpropanesulfonic acid and 10 g surfactant AOS are added to prepare nano-absorption oil displacement agent SX-4.

[0067] Embodiment 5-8

[0068] Preparation of nano-absorption oil displacement agent solutions SXY-1 to SXY4:

[0069] 0.3 g of the nano-imbibition oil-displacing agent in Examples 1-4 was weighed respectively, placed in a 200 mL beaker, and 99.7 g of deionized water was added to prepare nano-imbibition oil-displacing agent solutions SXY-1 to SXY-4 with a mass concentration of 0.3 wt %.

[0070] Comparative Example 1

[0071] The preparation method is the same as that of Example 1, except that in step (1), the monomers added are 15 g acrylamide, 10 g N-dodecyl acrylamide and 20 g sodium tetradecene α-ene sulfonate, respectively, to prepare nano-absorption oil displacement agent SX-5.

[0072] Comparative Example 2

[0073] The preparation method is the same as that of Example 1, except that in step (1), 25 g of acrylamide and 5 g of surfactant AOS are added to prepare nano-absorption oil displacement agent SX-6.

[0074] Comparative Example 3

[0075] The preparation method is the same as that of Example 1, except that in step (1), 25 g of 2-acrylamide-2-methylpropanesulfonic acid and 5 g of surfactant AOS are added to prepare nano-absorption oil displacement agent SX-7.

[0076] Comparative Example 4

[0077] The preparation method is the same as that of Example 1, except that in step (1), the surfactant used is dodecylphenol polyoxyethylene ether OP-10, and the nano-infiltration oil-displacing agent SX-8 is prepared.

[0078] Comparative Examples 5-8

[0079] Preparation of nano-absorption oil displacement agent solution SXY-5~SXY-8:

[0080] 0.3 g of the nano-imbibition oil-displacing agent in Comparative Examples 1-4 was weighed respectively, placed in a 200 mL beaker, and 99.7 g of deionized water was added to prepare nano-imbibition oil-displacing agent solutions SXY-5 to SXY-8 with a mass concentration of 0.3 wt %.

[0081] Test example: Performance evaluation of nano-absorption oil displacement agent solution:

[0082] (1) Particle size distribution of nano-imbibition oil displacement agent solution

[0083] The nano-absorption oil displacement agent can be dispersed in deionized water to form a nano-scale solution, and its particle size distribution is tested using a Malvern laser particle size analyzer.

[0084] (2) Interfacial tension of nano-infiltration oil displacement agent solution

[0085] The interfacial tension between the nano-imbibition oil displacement agent solution, the conventional surfactant solution (0.3wt% AOS), deionized water and Jimusar shale oil was measured by an interfacial tension meter.

[0086] (3) Wettability improvement ability of nano-infiltration oil displacement agent solution

[0087] (a) The Jimusar core was cut into 5 mm thick slices and the wetting angle of the core slices was measured;

[0088] (b) immersing the core pieces in a nano-infiltration oil displacement agent solution and a conventional surfactant solution (0.3 wt % AOS) respectively at room temperature for 24 h, and then taking them out and drying them;

[0089] (c) The contact angle of deionized water was tested using a JY-82C-N2 contact angle meter, and the contact angles of the core pieces after being soaked in different solutions were compared with those of the core pieces not treated with the sample solution.

[0090] (4) Adhesion work reduction capability of nano-infiltration oil displacement agent solution

[0091] The adhesion work of the nano-absorption oil displacement agent solution was calculated according to the following formula, and its adhesion work reduction rate was calculated based on this to evaluate its adhesion work reduction ability:

[0092] W=σ ow (1-cosθ)

[0093] Among them, σ ow is the interfacial tension between Jimusar shale oil and different solutions; θ is the contact angle between the core and different solutions.

[0094] (5) Spontaneous imbibition recovery rate of nanoimbibition oil displacement agent solution

[0095] The prepared nano-infiltration oil displacement agent solution, conventional surfactant solution (0.3 wt% AOS) and deionized water were mixed in a 0.1×10 -3 μm 2 Spontaneous imbibition experiments were carried out in the core at room temperature and the oil used in the experiments was Jimusar shale oil.

[0096] The above Examples 5-8, Comparative Examples 5-8, conventional surfactant solution (0.3 wt % AOS) solution and deionized water were tested for interfacial tension, contact angle, adhesion work and spontaneous imbibition recovery rate according to the above method. The test results are shown in Table 1;

[0097] Table 1 Performance test results of different solution systems

[0098]

[0099] Test results:

[0100] The particle size distribution of 0.3wt% nano-infiltration oil displacement agent solution SXY-1, SXY-7, and SXY-8 is as follows Figure 1 As shown, the particle size of the nano-imbibition oil-displacing agent SX-1 prepared in Example 1 of the present invention is 2-6nm, which can penetrate into the small and complex pore throats of the shale reservoir to displace crude oil, improve the degree of sweep, and enhance the spontaneous imbibition effect; while the particle sizes of the nano-imbibition oil-displacing agents XS-7 and XS-8 prepared in the comparative example are both greater than 5nm, with the maximum reaching 30nm, and the spontaneous imbibition effect will be greatly reduced.

[0101] The interfacial tension diagram of 0.3wt% nano-infiltration oil displacement agent solution A is shown in Figure 2 As shown in the figure, the nano-imbibition oil displacement agent solution SXY-1 prepared in the embodiment of the present invention and Jimusar shale oil reach an equilibrium interfacial tension value of 0.07 mN·m in a short time. -1 , which has the ability to moderately reduce the starting pressure of oil-water interfacial tension, can increase capillary force, improve spreading coefficient, increase the power of imbibition oil displacement and the degree of crude oil stripping on the core surface; while the equilibrium interfacial tension values ​​of nano-imbibition oil displacement agent solutions XSY-7 and XSY-8 prepared in the comparative example are higher than 0.1 mN·m -1 ; The equilibrium interfacial tension value of conventional surfactant solution is 0.1837mN·m -1 .

[0102] The spontaneous imbibition recovery results of the nano-imbibition oil displacement agent solution, surfactant AOS and water prepared in Examples 5-8 of the present invention in shale oil reservoirs are as follows: Figure 3 As shown, the spontaneous imbibition recovery results of the nano-imbibition oil displacement agent solutions prepared in Comparative Examples 7 and 8 in shale oil reservoirs are as follows Figure 4 As shown; the spontaneous imbibition recovery rate of the nano-imbibition agent oil-displacing agent solution (0.3wt%) prepared in Examples 5-8 is as high as over 30%, which is higher than that of Comparative Examples 7 and 8; and is much higher than the spontaneous imbibition recovery rate of a conventional surfactant (0.3wt% AOS) solution (25%) and the spontaneous imbibition recovery rate of deionized water (13%).

[0103] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions of the technical solution of the present invention by ordinary technicians in this field do not deviate from the essence and scope of the technical solution of the present invention.

Claims

1. A nano-infiltration oil displacement agent, characterized in that: The nano-infiltration oil-displacing agent is obtained by polymerization reaction of acrylamide monomers and surfactants; the acrylamide monomers include at least one of acrylamide, 2-acrylamido-2-methylpropane sulfonic acid, N-dodecyl acrylamide and 4-acryloylmorpholine; the surfactant includes at least one of α-olefin sulfonate, alkylphenol polyoxyethylene ether and sodium dodecyl sulfate.

2. The nano-infiltration oil-displacing agent according to claim 1, characterized in that The acrylamide monomers at least include acrylamide, and the surfactant is α-olefin sulfonate.

3. The nano-infiltration oil-displacing agent according to claim 2, characterized in that, The amount of the acrylamide monomers is: 10-30wt% of acrylamide, 0-15wt% of 2-acrylamido-2-methylpropanesulfonic acid, 0-10wt% of N-dodecylacrylamide and 0-10wt% of 4-acryloylmorpholine; the amount of the surfactant is 5-20wt%.

4. The nano-infiltration oil displacement agent according to any one of claims 1 to 3, characterized in that: The particle size of the nano-infiltration oil-displacing agent is 1-10 nm.

5. according to the preparation method of the arbitrary described nano-infiltration oil displacement agent of claim 1-4, it is characterized in that, The following steps are involved: (1) adding acrylamide monomers and surfactants into a reaction device; (2) Under the protection of an inert atmosphere, add water to fully dissolve and adjust the pH; (3) Raise the temperature, add an initiator, and carry out a polymerization reaction to obtain the product.

6. The preparation method according to claim 5, characterized in that: The amount of the initiator used accounts for 0.08-1.0 wt % of the total amount of the acrylamide monomer and the surfactant.

7. The preparation method according to claim 5, characterized in that: The initiator comprises an oxidant and a reductant; the mass ratio of the oxidant to the reductant is 1:0.7-0.8; the oxidant is selected from at least one of ammonium persulfate, sodium persulfate and potassium persulfate; and the reductant is selected from sodium sulfite or sodium bisulfite.

8. The preparation method according to claim 5, characterized in that: In step (2), the pH value is 6.0-8.0; in step (3), the polymerization reaction temperature is 50-70° C.; and the polymerization time is 3-5 hours.

9. A nano-absorption oil displacement agent solution, characterized in that: The invention comprises the nano-infiltration oil-displacing agent according to any one of claims 1 to 4 or the nano-infiltration oil-displacing agent prepared by the preparation method according to any one of claims 5 to 8.

10. The nano-infiltration oil displacement agent solution according to claim 9, characterized in that: The solvent of the solution is deionized water or formation water; the concentration of the nano-infiltration oil-displacing agent in the nano-infiltration oil-displacing agent solution is 0.1-2.0wt%.

11. Application of a nano-imbibition oil displacement agent or a nano-imbibition oil displacement agent solution in shale oil reservoir fracturing displacement, characterized in that: The nano-infiltration oil-displacing agent is the nano-infiltration oil-displacing agent described in any one of claims 1-4 or the nano-infiltration oil-displacing agent prepared by the preparation method described in any one of claims 5-8; the nano-infiltration oil-displacing agent solution is the nano-infiltration oil-displacing agent solution described in claim 9 or 10.

12. The use according to claim 11, characterized in that: The shale oil reservoir has a formation temperature of ≤100°C, a formation water mineralization of 0-10000 mg / L, and a permeability of (0.01-1.0)×10 -3 μm 2 .

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