A method and system for powerfully reducing adhesion work and flooding oil

Abstract

The present invention relates to a method and system for strong adhesion work reduction oil displacement, belonging to the technical field of oil and gas field development, and includes: (1) determining the viscosity and density of high-viscosity crude oil in the target oil reservoir; (2) optimizing the carbon chain length and injection concentration of the tension-reducing and adhesion-reducing oil displacement agent; (3) testing the oil washing ability of the tension-reducing and adhesion-reducing oil displacement agent; (4) testing the effect of improving the recovery rate of the tension-reducing and adhesion-reducing oil displacement agent; (5) determining the adaptability of the adhesion work reduction oil displacement method. The present invention aims at the difficulty that the adhesion work between high-viscosity crude oil and rock is high, and the high-viscosity crude oil cannot be started and migrated by reducing the oil-water interface tension alone, and changes from the traditional "focusing on the oil-water interface" to "giving equal importance to the oil-water and solid-liquid interfaces", and proposes a strong adhesion work reduction oil displacement method, which is of great significance for greatly improving the recovery rate of chemical flooding in high-viscosity oil reservoirs.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas field development, and in particular relates to a method and system for powerfully reducing adhesion work to drive oil. Background Art

[0002] Chemical flooding is the most powerful measure to improve oil recovery, and its application scale and oil-increasing effect in mines rank first in the world. However, with the promotion of chemical flooding, reservoir conditions are becoming more and more demanding. In high-viscosity reservoirs, crude oil has high viscosity and high adhesion work, and the oil displacement agent has poor efficiency in washing the remaining oil.

[0003] Traditionally, it is believed that surfactants form an adsorption layer at the oil-water interface, significantly reducing the interfacial tension between oil and water, increasing the number of capillaries, and thus weakening the capillary force, making it easier for crude oil to be displaced by water in the pores. Therefore, the research and development and application of traditional oil displacement agents mainly focus on the oil-water interfacial tension. However, the long-term development of old oil fields has led to scattered distribution of residual oil, especially high adhesion work between high-viscosity crude oil and rock. The residual oil adhering to the rock surface in the affected area has a large starting pressure gradient. Reducing the oil-water interfacial tension alone cannot start and migrate high-viscosity crude oil. Reducing the adhesion work is the key to efficiently starting the residual oil.

[0004] For high-viscosity oil reservoirs, how to adjust the design ideas of oil displacement agents and propose a method of strong adhesion work reduction to greatly reduce the adhesion work between crude oil and rocks while ensuring the reduction of interfacial tension, and enhance the ability of crude oil to start migration, is the bottleneck problem faced by chemical flooding to enhance crude oil recovery in high-viscosity oil reservoirs. Summary of the invention

[0005] In view of the high adhesion work of crude oil in high-viscosity reservoirs and the shortcomings of the existing technology, the present invention changes the traditional chemical flooding method of "focusing on the oil-water interface" to "giving equal importance to the oil-water and solid-liquid interfaces", and proposes a method of flooding with strong adhesion work reduction. Through the reasonable optimization and testing of the oil-displacing agent, the oil-displacing agent is encouraged to enrich and penetrate at the oil-water interface, reduce the oil-water interfacial tension and disperse the oil droplets; enrich and adsorb at the rock solid-liquid interface, reduce the adhesion work and strip the crude oil, and realize the wall crude oil startup, which can provide important guidance for chemical flooding of high-viscosity reservoirs to significantly improve the recovery rate.

[0006] The invention also proposes a powerful adhesion reduction work oil displacement system.

[0007] Terminology explanation:

[0008] 1. Interfacial tension: the contraction force acting on the oil-water interface per unit length.

[0009] 2. Carbon chain length: the length of the continuous chain formed by carbon atoms in the oil displacement agent molecule.

[0010] 3. Adhesion work: the work required to separate two adjacent phases.

[0011] 4. Contact angle: The angle between the tangent line of the oil-water interface at the intersection of oil, water and solid and the oil-solid boundary line.

[0012] 5. The petroleum densitometer method is a method based on Archimedes' principle that uses a glass petroleum densitometer to measure the density of liquid petroleum and other fluid liquid products.

[0013] The technical solution adopted by the present invention is:

[0014] A method for flooding oil by strongly reducing adhesion work comprises the following steps:

[0015] (1) Determine the viscosity and density of high-viscosity crude oil in the target reservoir;

[0016] (2) Optimizing the carbon chain length and injection concentration of the tension-reducing and adhesion-reducing oil displacement agent;

[0017] (3) Testing the oil washing ability of tension and adhesion reducing oil displacement agents;

[0018] (4) Testing the effect of tension-reducing and adhesion-reducing oil displacement agents on improving oil recovery;

[0019] (5) Determine the adaptability of the oil recovery method by reducing adhesion work.

[0020] According to the preferred embodiment of the present invention, in step (1), the viscosity of the high-viscosity crude oil in the target reservoir is measured using a rheometer, and the shear rate is set to 7.34 s -1 ; The density of high-viscosity crude oil in the target reservoir is determined using the petroleum densitometer method.

[0021] According to the preferred embodiment of the present invention, in step (2), according to the type of oil displacement agent and injection conditions actually available in the mine, the carbon chain length value range of the tension-reducing and adhesion-reducing oil displacement agent is set to C 12 ~C 20 The injection concentration range is set to 1000 mg / L to 3000 mg / L. The oil displacement agent solutions with different carbon chain lengths and different injection concentrations were mixed with crude oil uniformly, and the oil-water interfacial tension and solid-liquid interfacial adhesion work were measured. -2 mN / m and the solid-liquid interface adhesion work is less than 8×10 -4 mJ / m 2 Among all the oil displacement agent solutions, the minimum injection concentration value and the minimum carbon chain length under the minimum injection concentration value are taken as the preliminary optimization results.

[0022] Further preferably, in step (2), the specific method for measuring the oil-water interfacial tension is:

[0023] Prepare oil displacement agent solutions with different carbon chain lengths and different injection concentrations and inject them into test tubes; then drop oil drops into the test tubes to suspend the oil drops in the oil displacement agent solution; seal the test tubes and install them in an interfacial tension tester, adjust the speed, and measure the interfacial tension after the system is balanced; oil-water interfacial tension The calculation formula is:

[0024] ;

[0025] In the formula, is the density of the oil displacement agent solution, is the density of crude oil, is the maximum diameter of the dimensionless oil droplet, It is the time required for the interfacial tension meter to make one rotation.

[0026] Further preferably, in step (2), the specific method for measuring the solid-liquid interface adhesion work is:

[0027] Use a microsyringe to drop crude oil on the surface of a rock slice, and then place it in a container containing oil displacement agent solutions of different carbon chain lengths and different injection concentrations to ensure that the rock slice and the oil drop are covered. Use a microscope and image processing software to measure the contact angle between the oil drop and the surface of the rock slice. Calculate the adhesion work between the oil drop and the surface of the rock slice based on the interfacial tension and contact angle. The calculation formula is:

[0028] ;

[0029] In the formula, is the adhesion work between crude oil and rock slice surface in oil displacement agent solution, is the oil-water interfacial tension between the oil displacement agent solution and the crude oil, is the contact angle between the oil droplet and the rock slice surface in the oil displacement agent solution, is the cosine function.

[0030] According to a preferred embodiment of the present invention, in step (3), the test method for the oil washing ability of the tension and adhesion reducing oil displacement agent is:

[0031] The volume is The target reservoir high viscosity crude oil is mixed with quartz sand and then added to a beaker for aging; then the oil displacement agent solution is added and allowed to stand until the oil and water separate, and the volume of the heavy oil separated from the quartz sand in the beaker is measured. ; Calculate oil washing rate , the specific formula is:

[0032] ;

[0033] In the formula, is the oil washing rate of the oil displacement agent solution, is the volume of crude oil mixed with quartz sand, is the volume of crude oil separated from the quartz sand in the beaker.

[0034] According to a preferred embodiment of the present invention, in step (4), the test method for the enhanced oil recovery effect of the tension-reducing and adhesion-reducing oil displacement agent is:

[0035] Two groups of sand-filled tube models with a permeability difference of less than 5% were prepared by filling quartz sand, and saturated with water and high-viscosity crude oil in turn. The first group of sand-filled tube models were injected with water to displace oil until no oil was produced from the outlet of the sand-filled tube; the second group of sand-filled tube models were injected with water to displace oil until the water content reached 95%, and then 0.2PV-0.6PV of the preferred oil-displacing agent solution in step (2) was injected. After the injection was completed, water was continued to displace oil until no oil was produced from the outlet of the sand-filled tube. The improvement in crude oil recovery factor of the two groups of sand-filled tube models was calculated, and the calculation formula was:

[0036] ;

[0037] In the formula, is the enhanced oil recovery value of the oil displacement agent solution, is the saturated crude oil volume of the second group of sand-filled tube models, is the cumulative crude oil volume produced by the second group of sand-filled pipe models, is the saturated crude oil volume of the first group of sand-filled tube models, Cumulative crude oil volume produced for the first set of sand-filled pipe models.

[0038] Further preferably, 0.4 PV of the preferred oil displacement agent solution in step (2) is injected.

[0039] According to a preferred embodiment of the present invention, in step (5), the adaptability determination method of the adhesion reduction work displacement method is:

[0040] If the oil washing rate measured in step (3) is greater than 15%, and the enhanced oil recovery value measured in step (4) is greater than 3%, it means that the preferred tension-reducing and adhesion-reducing oil-displacing agent in step (2) has good adaptability to the high-viscosity crude oil in the target oil reservoir in step (1); otherwise, the preferred minimum injection concentration in step (2) is kept unchanged, an oil-displacing agent with a larger carbon chain length is selected, and the tests in steps (3) and (4) are repeated until an oil-displacing agent with good adaptability to the high-viscosity crude oil in the target oil reservoir is selected.

[0041] A powerful adhesion reduction work displacement system, comprising:

[0042] The module for determining the viscosity and density of the high-viscosity crude oil in the target oil reservoir is configured to: determine the viscosity and density of the high-viscosity crude oil in the target oil reservoir;

[0043] The oil displacement agent optimization module is configured to: optimize the carbon chain length and injection concentration of the tension-reducing and adhesion-reducing oil displacement agent;

[0044] The oil washing ability test module is configured to: test the oil washing ability of the tension-reducing and adhesion-reducing oil displacement agent;

[0045] The enhanced oil recovery effect test module is configured to: test the enhanced oil recovery effect of the tension-reducing and adhesion-reducing oil displacement agent;

[0046] The adaptability determination module is configured to determine the adaptability of the adhesion reduction work displacement method.

[0047] The beneficial effects of the present invention are:

[0048] 1. Aiming at the difficulty that the adhesion work between high-viscosity crude oil and rock is high and the starting pressure gradient is large, and the high-viscosity crude oil cannot be started and migrated by reducing the oil-water interfacial tension alone, the present invention changes the traditional "focusing on the oil-water interface" to "giving equal importance to the oil-water and solid-liquid interfaces", and proposes a method for oil displacement with strong adhesion work reduction. While ensuring the reduction of interfacial tension, the adhesion work between crude oil and rock is greatly reduced, and the wall crude oil is started, which can provide guidance for chemical flooding of high-viscosity reservoirs to greatly improve the recovery rate.

[0049] 2. A method for selecting oil displacement agents for target oil reservoirs is provided. By comparing the interfacial tension and adhesion work of oil displacement agent solutions with different carbon chain lengths and different concentrations and high-viscosity crude oil, an oil displacement agent with better matching with the target crude oil is determined. The oil washing capacity and enhanced oil recovery tests are also conducted to ensure the adaptability of the oil displacement agent selected for the target oil reservoir, thus avoiding the problem of economic losses in the mine due to improper selection of oil displacement agents that affect the effect of enhanced oil recovery. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 Schematic diagram of the mechanism of starting the residual oil by the strong adhesion reduction work displacement method;

[0051] Figure 2 Schematic diagram of interfacial tension between different oil displacement agent solutions and crude oil;

[0052] Figure 3 Schematic diagram of adhesion work between different oil displacement agent solutions and rocks;

[0053] Figure 4 Schematic diagram of the oil washing effect of oil displacement agent solution. DETAILED DESCRIPTION

[0054] In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, further detailed description will be given below in conjunction with specific embodiments.

[0055] Example 1

[0056] A method for flooding oil by strongly reducing adhesion work comprises the following steps:

[0057] (1) Determine the viscosity and density of high-viscosity crude oil in the target reservoir;

[0058] (2) Optimizing the carbon chain length and injection concentration of the tension-reducing and adhesion-reducing oil displacement agent;

[0059] (3) Testing the oil washing ability of tension and adhesion reducing oil displacement agents;

[0060] (4) Testing the effect of tension-reducing and adhesion-reducing oil displacement agents on improving oil recovery;

[0061] (5) Determine the adaptability of the oil recovery method by reducing adhesion work.

[0062] Example 2

[0063] The difference between the method for flooding oil with strong adhesion reduction work power according to Example 1 is that:

[0064] In step (1), the viscosity of the high-viscosity crude oil in the target reservoir was measured using a rheometer, and the shear rate was set to 7.34 s -1 When using a rheometer to test viscosity, the fixed shear rate is determined according to the material properties, viscosity range and test purpose, usually 1s -1 -100 s -1 , 7.34 s is generally used to measure crude oil viscosity. -1 The density of the target high-viscosity crude oil in the reservoir was measured by the petroleum densimeter method. In this embodiment, the high-viscosity crude oil was taken from a high-viscosity reservoir in Shengli Oilfield. The viscosity of the target high-viscosity crude oil was measured to be 658 mPa·s. The density of the target high-viscosity crude oil was measured by the petroleum densimeter method to be 913 kg / m 3 .

[0065] In step (2), due to the high adhesion work between high-viscosity crude oil and rock, the starting pressure gradient of the residual oil adhering to the rock surface in the affected area is large, and it is impossible to start and migrate high-viscosity crude oil by simply reducing the oil-water interfacial tension. Therefore, the traditional "focus on the oil-water interface" is changed to "give equal attention to the oil-water and solid-liquid interfaces". The oil displacement agent is enriched and penetrated at the oil-water interface, and the oil droplets are dispersed by reducing the oil-water interfacial tension; the oil is enriched and adsorbed at the rock solid-liquid interface, and the adhesion work is reduced to strip the crude oil, so as to achieve the wall crude oil startup, such as Figure 1 shown.

[0066] The carbon chain length and injection concentration are the key factors affecting the tension and adhesion reduction work of the oil displacement agent. According to the actual types of oil displacement agents and injection conditions in the mine, the carbon chain length value range of the tension and adhesion reduction work of the oil displacement agent is set to C 12 ~C 20 , specifically C 12 , C 14 , C 16 , C 18 , C 20The injection concentration range is set to 1000 mg / L to 3000 mg / L, specifically 1000 mg / L, 1500 mg / L, 2000 mg / L, 2500 mg / L, and 3000 mg / L; the optimization is carried out through the interfacial tension and adhesion work between the oil displacement agent solution and the crude oil and rock.

[0067] First, prepare oil-displacing agent solutions with different carbon chain lengths and different injection concentrations and inject them into a test tube; then drop oil drops into the test tube to suspend the oil drops in the oil-displacing agent solution; seal the test tube and install it in an interfacial tension measuring instrument, adjust the speed, and measure the interfacial tension after the system is balanced; the oil-water interfacial tension The calculation formula is:

[0068] ;

[0069] In the formula, is the density of the oil displacement agent solution, is the density of crude oil, is the maximum diameter of the dimensionless oil droplet, It is the time required for the interfacial tension meter to make one rotation.

[0070] Use a microsyringe to drop crude oil on the surface of a rock slice, and put it into a container containing oil displacement agent solutions of different carbon chain lengths and different injection concentrations to ensure that the rock slice and the oil drop are covered. Use a microscope and image processing software to measure the contact angle between the oil drop and the surface of the rock slice. Specifically, use a microscope and a camera to take a photo of the contact between the oil drop and the surface of the rock slice, use image processing software to determine the contact point between the oil drop and the slice in the photo, and use this as the starting point to draw a tangent to the oil drop. The angle between the tangent and the surface of the rock slice is the contact angle. Calculate the adhesion work between the oil drop and the surface of the rock slice based on the interfacial tension and the contact angle. The adhesion work at the solid-liquid interface The calculation formula is:

[0071] ;

[0072] In the formula, is the adhesion work between crude oil and the surface of rock slice in the oil displacement agent solution, is the oil-water interfacial tension between the oil displacement agent solution and the crude oil, is the contact angle between the oil droplet and the rock slice surface in the oil displacement agent solution, is the cosine function.

[0073] In this embodiment, the concentration and carbon chain length of the oil displacement agent solution configuration 1 are 1000 mg / L and C 12 The concentration and carbon chain length of configuration 2 are 1000 mg / L and C 14The concentration and carbon chain length of configuration 3 were 1000 mg / L and C 16 The concentration and carbon chain length of configuration 4 are 1000 mg / L and C 18 The concentration and carbon chain length of configuration 5 were 1000 mg / L and C 20 The concentration and carbon chain length of configuration 6 were 1500 mg / L and C 12 The concentration and carbon chain length of configuration 7 were 1500 mg / L and C 14 The concentration and carbon chain length of configuration 8 were 1500 mg / L and C 16 The concentration and carbon chain length of configuration 9 were 1500 mg / L and C 18 The concentration and carbon chain length of configuration 10 were 1500 mg / L and C 20 The concentration and carbon chain length of configuration 11 were 2000 mg / L and C 12 The concentration and carbon chain length of configuration 12 were 2000 mg / L and C 14 The concentration and carbon chain length of configuration 13 were 2000 mg / L and C 16 The concentration and carbon chain length of configuration 14 were 2000 mg / L and C 18 The concentration and carbon chain length of configuration 15 were 2000 mg / L and C 20 The concentration and carbon chain length of configuration 16 were 2500 mg / L and C 12 The concentration and carbon chain length of configuration 17 were 2500 mg / L and C 14 The concentration and carbon chain length of configuration 18 were 2500 mg / L and C 16 The concentration and carbon chain length of configuration 19 were 2500 mg / L and C 18 The concentration and carbon chain length of configuration 20 are 2500 mg / L and C 20 The concentration and carbon chain length of configuration 21 were 3000 mg / L and C 12 The concentration and carbon chain length of configuration 22 were 3000 mg / L and C 14 The concentration and carbon chain length of configuration 23 were 3000 mg / L and C 16 The concentration and carbon chain length of configuration 24 were 3000 mg / L and C 18 The concentration and carbon chain length of configuration 25 were 3000 mg / L and C 20 .

[0074] The interfacial tension test results between oil displacement agent solutions with different carbon chain lengths and different concentrations and crude oil are shown in Figure 2. Figure 2 The test results of adhesion work between the rock and the Figure 3 As shown. -2 mN / m and the adhesion work is less than 8×10 -4 mJ / m 2 The smallest carbon chain length and concentration value used in all oil displacement agent solutions is taken as the preferred result. In this embodiment, the preferred oil displacement agent carbon chain length is C 14 , concentration is 1500 mg / L.

[0075] In step (3), the test method for the oil washing ability of the tension and adhesion reducing oil displacement agent is:

[0076] Mix 10 mL of high-viscosity crude oil from the target reservoir with quartz sand and add it to a beaker for aging for 7 days. Then add the oil displacement agent solution and wait for 48 hours. Figure 4 As shown in the figure, after oil-water separation, the volume of heavy oil separated from the quartz sand in the measuring beaker is 3.4 mL, and the oil washing rate is calculated to be 34%. The specific calculation formula is:

[0077] ;

[0078] In the formula, is the oil washing rate of the oil displacement agent solution, is the volume of crude oil mixed with quartz sand, is the volume of crude oil separated from the quartz sand in the beaker.

[0079] In step (4), the test method for improving the recovery efficiency of the tension-reducing and adhesion-reducing oil displacement agent is as follows:

[0080] Two groups of sand-filled tube models with a permeability difference of less than 5% were prepared by filling quartz sand, and saturated with water and high-viscosity crude oil in turn. The first group of sand-filled tube models was injected with water to displace oil until no oil was produced at the outlet of the sand-filled tube; the second group of sand-filled tube models was injected with water to displace oil until the water content reached 95%, and then 0.4 PV of the preferred oil-displacing agent solution in step (2) was injected. After the injection was completed, water was continued to displace oil until no oil was produced at the outlet of the sand-filled tube. The improvement in crude oil recovery factor of the two groups of sand-filled tube models was calculated, and the calculation formula was:

[0081] ;

[0082] In the formula, is the enhanced oil recovery value of the oil displacement agent solution, is the saturated crude oil volume of the second group of sand-filled tube models, is the cumulative crude oil volume produced by the second group of sand-filled pipe models, is the saturated crude oil volume of the first group of sand-filled tube models, Cumulative crude oil volume produced for the first set of sand-filled pipe models.

[0083] Two sets of sand-filled tube models with similar permeability were made by using quartz sand; specifically, the quartz sand was washed with deionized water, dried, and then added to the sand-filled tube in small amounts and multiple times, compacted using a semi-automatic sand-filling compaction device, and the surroundings of the sand-filled tube were knocked to prevent the core from having a cross section, and the filling-compacting-knocking operation was repeated in sequence until the entire sand-filled tube was filled with quartz sand. As a comparative experiment, the permeability difference between the two sets of sand-filled tube models was required to be less than 5%.

[0084] In this embodiment, the permeability of the first group of sand-filled pipe models is 98510 -3 μm 2 The saturated crude oil volume is 29 mL, and the cumulative crude oil volume produced is 8 mL; the permeability of the second group of sand-filled pipe models is 101310 -3 μm 2 The saturated crude oil volume is 30 mL, the cumulative crude oil volume produced is 11 mL, and the calculated enhanced oil recovery value is 9%.

[0085] In step (5), the adaptability judgment method of the oil displacement method by reducing adhesion work is:

[0086] The oil washing efficiency measured in step (3) is 34%, which is greater than 15%; the enhanced oil recovery value measured in step (4) is 9%, which is greater than 3%. Therefore, the preferred tension-reducing and adhesion-reducing oil displacement agent in step (2) has good adaptability to the high-viscosity crude oil in the target reservoir in step (1).

[0087] Example 3

[0088] A powerful adhesion reduction work displacement system, comprising:

[0089] The module for determining the viscosity and density of the high-viscosity crude oil in the target oil reservoir is configured to: determine the viscosity and density of the high-viscosity crude oil in the target oil reservoir;

[0090] The oil displacement agent optimization module is configured to: optimize the carbon chain length and injection concentration of the tension-reducing and adhesion-reducing oil displacement agent;

[0091] The oil washing ability test module is configured to: test the oil washing ability of the tension-reducing and adhesion-reducing oil displacement agent;

[0092] The enhanced oil recovery effect test module is configured to: test the enhanced oil recovery effect of the tension-reducing and adhesion-reducing oil displacement agent;

[0093] The adaptability determination module is configured to determine the adaptability of the adhesion reduction work displacement method.

Claims

1. A method for flooding oil by strongly reducing adhesion work, characterized in that: The steps include: (1) Determine the viscosity and density of high-viscosity crude oil in the target reservoir; (2) Optimizing the carbon chain length and injection concentration of the tension-reducing and adhesion-reducing oil displacement agent; (3) Testing the oil washing ability of tension and adhesion reducing oil displacement agents; (4) Testing the effect of tension-reducing and adhesion-reducing oil displacement agents on improving oil recovery; (5) Determine the adaptability of the oil recovery method by reducing the adhesion work; In step (2), according to the type of oil displacement agent and injection conditions actually available in the mine, the carbon chain length range of the tension-reducing and adhesion-reducing oil displacement agent is set to C 12 ~C 20 The injection concentration range is set to 1000 mg / L to 3000 mg / L. The oil displacement agent solutions with different carbon chain lengths and different injection concentrations were mixed with crude oil uniformly, and the oil-water interfacial tension and solid-liquid interfacial adhesion work were measured. -2 mN / m and the solid-liquid interface adhesion work is less than 8×10 -4 mJ / m 2 Among all the oil displacement agent solutions, the minimum injection concentration value and the minimum carbon chain length under the minimum injection concentration value are taken as the preliminary optimization results.

2. A method for flooding oil by reducing adhesion power according to claim 1, characterized in that: In step (1), the viscosity of the high-viscosity crude oil in the target reservoir was measured using a rheometer, and the shear rate was set to 7.34 s -1 ; The density of high-viscosity crude oil in the target reservoir is determined using the petroleum densitometer method.

3. A method for flooding oil by reducing adhesion power according to claim 1, characterized in that: In step (2), the specific method for measuring the oil-water interfacial tension is: Prepare oil displacement agent solutions with different carbon chain lengths and different injection concentrations and inject them into test tubes; then drop oil drops into the test tubes to suspend the oil drops in the oil displacement agent solution; seal the test tubes and install them in an interfacial tension tester, adjust the speed, and measure the interfacial tension after the system is balanced; oil-water interfacial tension The calculation formula is: ; In the formula, is the density of the oil displacement agent solution, is the density of crude oil, is the maximum diameter of the dimensionless oil droplet, It is the time required for the interfacial tension meter to make one rotation.

4. A method for flooding oil by reducing adhesion power according to claim 3, characterized in that: In step (2), the specific method for measuring the solid-liquid interface adhesion work is: Use a microsyringe to drop crude oil on the surface of a rock slice, and then place it in a container containing oil displacement agent solutions of different carbon chain lengths and different injection concentrations to ensure that the rock slice and the oil drop are covered. Use a microscope and image processing software to measure the contact angle between the oil drop and the surface of the rock slice. Calculate the adhesion work between the oil drop and the surface of the rock slice based on the interfacial tension and contact angle. The calculation formula is: ; In the formula, is the adhesion work between crude oil and rock slice surface in oil displacement agent solution, is the oil-water interfacial tension between the oil displacement agent solution and the crude oil, is the contact angle between the oil droplet and the rock slice surface in the oil displacement agent solution, is the cosine function.

5. A method for flooding oil by reducing adhesion power according to claim 1, characterized in that: In step (3), the test method for the oil washing ability of the tension and adhesion reducing oil displacement agent is: The volume is The target reservoir high viscosity crude oil is mixed with quartz sand and then added to a beaker for aging; then the oil displacement agent solution is added and allowed to stand until the oil and water separate, and the volume of the heavy oil separated from the quartz sand in the beaker is measured. ; Calculate oil washing rate , the specific formula is: ; In the formula, is the oil washing rate of the oil displacement agent solution, is the volume of crude oil mixed with quartz sand, is the volume of crude oil separated from the quartz sand in the beaker.

6. A method for flooding oil by reducing adhesion power according to claim 5, characterized in that: In step (4), the test method for improving the recovery efficiency of the tension-reducing and adhesion-reducing oil displacement agent is as follows: Two groups of sand-filled tube models with a permeability difference of less than 5% were prepared by filling quartz sand, and saturated with water and high-viscosity crude oil in turn. The first group of sand-filled tube models were injected with water to displace oil until no oil was produced from the outlet of the sand-filled tube; the second group of sand-filled tube models were injected with water to displace oil until the water content reached 95%, and then 0.2PV-0.6PV of the preferred oil-displacing agent solution in step (2) was injected. After the injection was completed, water was continued to displace oil until no oil was produced from the outlet of the sand-filled tube. The improvement in crude oil recovery factor of the two groups of sand-filled tube models was calculated, and the calculation formula was: ; In the formula, is the enhanced oil recovery value of the oil displacement agent solution, is the saturated crude oil volume of the second group of sand-filled tube models, is the cumulative crude oil volume produced by the second group of sand-filled pipe models, is the saturated crude oil volume of the first group of sand-filled tube models, Cumulative crude oil volume produced for the first set of sand-filled pipe models.

7. A method for flooding oil by reducing adhesion power according to claim 5, characterized in that: Inject 0.4 PV of the preferred oil displacement agent solution of step (2).

8. A method for flooding oil by reducing adhesion power according to claim 1, characterized in that: In step (5), the adaptability judgment method of the oil displacement method by reducing adhesion work is: If the oil washing rate measured in step (3) is greater than 15%, and the enhanced oil recovery value measured in step (4) is greater than 3%, it means that the preferred tension-reducing and adhesion-reducing oil-displacing agent in step (2) has good adaptability to the high-viscosity crude oil in the target oil reservoir in step (1); otherwise, the preferred minimum injection concentration in step (2) is kept unchanged, an oil-displacing agent with a larger carbon chain length is selected, and the tests in steps (3) and (4) are repeated until an oil-displacing agent with good adaptability to the high-viscosity crude oil in the target oil reservoir is selected.

9. A strong adhesion reduction work displacement system, used to implement a strong adhesion reduction work displacement method according to any one of claims 1 to 8, characterized in that: include: The module for determining the viscosity and density of the high-viscosity crude oil in the target oil reservoir is configured to: determine the viscosity and density of the high-viscosity crude oil in the target oil reservoir; The oil displacement agent optimization module is configured to: optimize the carbon chain length and injection concentration of the tension-reducing and adhesion-reducing oil displacement agent; according to the actual oil displacement agent type and injection conditions available in the mine, the carbon chain length value range of the tension-reducing and adhesion-reducing oil displacement agent is set to C 12 ~C 20 The injection concentration range is set to 1000 mg / L to 3000 mg / L. The oil displacement agent solutions with different carbon chain lengths and different injection concentrations were mixed with crude oil uniformly, and the oil-water interfacial tension and solid-liquid interfacial adhesion work were measured. -2 mN / m and the solid-liquid interface adhesion work is less than 8×10 -4 mJ / m 2 Among all the oil displacement agent solutions, the minimum injection concentration value and the minimum carbon chain length under the minimum injection concentration value are taken as the preliminary optimization results; The oil washing ability test module is configured to: test the oil washing ability of the tension-reducing and adhesion-reducing oil displacement agent; The enhanced oil recovery effect test module is configured to: test the enhanced oil recovery effect of the tension-reducing and adhesion-reducing oil displacement agent; The adaptability determination module is configured to determine the adaptability of the adhesion reduction work displacement method.

Images