Method, device and equipment for determining surface wettability of single mineral and storage medium

Abstract

The embodiment of the invention provides a method, device and equipment for determining surface wettability of a single mineral and a storage medium. The method comprises the following steps: respectively establishing a water molecule model, a crude oil component model and a pore-containing mineral model; respectively loading water molecules formed by the water molecule model and crude oil components formed by the crude oil component model into pores of the mineral model; optimizing the system model; performing molecular dynamics simulation on the optimized system model to obtain a mineral model with pores containing water molecules and crude oil components; respectively calculating the interaction energy of the mineral and water and the interaction energy of the mineral and crude oil components; and determining the oil-water wettability of the surface of the mineral according to the interaction energy of the mineral and the water and the interaction energy of the mineral and the crude oil component. In the embodiment of the invention, a measurement environment close to geological conditions can be created, corresponding experimental models are established for crude oil components and mineral components, and the characterization of the heterogeneity of the wettability of the reservoir is facilitated.

Description

Technical Field

[0001] The present application relates to the technical field of oil and gas exploration, and in particular to a method, device, equipment and storage medium for determining the wettability of a single mineral surface. Background Art

[0002] Wettability is the tendency of a phase of a mixed fluid to expand or adhere to a solid surface. The contact angle method commonly used to determine wettability mainly characterizes wettability by analyzing the three-phase contact angles of the solid surface in a water or air environment, and oil and water or air. Its advantages are simple measurement technology and a test range from strong water wetting to strong oil wetting, but sometimes the measurement results are not unique. The same rock sample has different mineral components at different locations, and will present different wettability results. It can be seen that the heterogeneity of minerals will lead to changes in the wettability of rocks, and the wettability of a single mineral is the determining factor in the wettability of rocks. In addition, the wettability measurements of the prior art are often carried out at room temperature, which makes it difficult to reflect the effect of temperature on the wettability of minerals.

[0003] Hydrocarbons are generated, migrated and gathered in an environment saturated with formation water. Formation water and hydrocarbons are two important fluids in rock pores. The contact angle of underground hydrocarbon fluid on the mineral surface is jointly determined by the properties of the three-phase material of mineral-hydrocarbon-formation water. A method for determining the surface wettability of reservoir rock minerals in the prior art is to determine the wettability of the three phases of mineral-oil droplet-air by scanning with an atomic force microscope. The measurement results of this method are highly accurate, but it is difficult to determine the wettability of minerals when there are two phases of oil and water on the mineral surface, and this method cannot create a temperature environment under formation conditions. Another method for determining the surface wettability of minerals in the prior art is to determine the surface wettability of a single mineral by measuring the contact angle of an oil droplet in water on the mineral surface. This method can clarify the wettability of minerals when there are two phases of oil and water on the mineral surface, but this method is limited to room temperature conditions and cannot determine the wettability of minerals under formation temperature conditions. In addition, the experimental operation requirements are high and the experimental process is time-consuming. Summary of the invention

[0004] In view of this, the present application provides a method, device, equipment and storage medium for determining the wettability of a single mineral surface, so as to solve the problems existing in the prior art.

[0005] In a first aspect, the present application provides a method for determining the wettability of a single mineral surface, comprising:

[0006] Establish water molecule model, crude oil component model and mineral model containing pores respectively;

[0007] loading water molecules composed of the water molecule model and crude oil components composed of the crude oil component model into the pores of the mineral model respectively, wherein the water molecules and the crude oil components have the same volume;

[0008] Optimizing the mineral model loaded with the water molecules and the crude oil components to obtain an optimized system model;

[0009] Performing molecular dynamics simulation on the optimized system model to obtain a mineral model containing water molecules and crude oil components in the pores;

[0010] Determining the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component according to the mineral model containing water molecules and crude oil components in the pores;

[0011] The oil-water wettability of the mineral surface is determined based on the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component.

[0012] In a possible implementation, establishing a crude oil component model includes:

[0013] Conduct group component analysis on the oil produced from rock reservoirs to obtain information on the crude oil components contained in the rock samples;

[0014] The component type with the highest content and typical hydrocarbon molecules therein are selected from the crude oil component information to establish a crude oil component model.

[0015] In a possible implementation, a mineral model containing pores is established, including:

[0016] A single mineral contained in a rock reservoir is selected to establish a mineral model containing pores, wherein the mineral model is a single-molecular-layer structure model or a multi-molecular-layer structure model.

[0017] In a possible implementation, the three-dimensional spatial dimensions of the pores of the mineral model are x, y, and z, respectively, wherein x and y are integer multiples of the length and width of a mineral unit cell, respectively, and x is twice y, and z≥y.

[0018] In a possible implementation, the water molecules composed of the water molecule model and the crude oil components composed of the crude oil component model are loaded into the pores of the mineral model respectively, including:

[0019] Establish water molecule models and crude oil component models of the same volume respectively;

[0020] Along the direction parallel to the surface of the mineral model, the water molecule model and the crude oil component model of the same volume are loaded into the pores of the mineral model respectively, so that the surface of the mineral model is occupied by water molecules and crude oil components respectively, and the surface areas occupied by the water molecules and the crude oil components are equal.

[0021] In a possible implementation, the optimizing the mineral model loaded with the water molecules and the crude oil components to obtain the optimized system model includes:

[0022] Performing geometric optimization on the mineral model loaded with the water molecules and the crude oil components;

[0023] The geometrically optimized mineral model is subjected to annealing simulation to obtain an optimized system model.

[0024] In a possible implementation, molecular dynamics simulation is performed on the optimized system model to obtain a mineral model containing water molecules and crude oil components in the pores, including:

[0025] The force field type is set for the optimized system model, and a simulated temperature condition is applied to perform molecular dynamics simulation to obtain a mineral model containing water molecules and crude oil components in the pores.

[0026] In a possible implementation, the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component are determined according to the mineral model containing water molecules and crude oil components in the pores, including:

[0027] According to the formula: ΔE m&w =(E m+o+w -E m&o -E w&o -E m -E w +E o +E m&w ) / 2Calculate the interaction energy between minerals and water;

[0028] According to the formula: ΔE m&o =(E m+o+w -E m&w -E w&o -E m -E o +E w +E m&o ) / 2Calculate the interaction energy between minerals and crude oil components;

[0029] Where, ΔE m&w , ΔE m&o They represent the interaction energy between minerals and water, and the interaction energy between minerals and crude oil components, respectively, in kcal / mol; E m+o+w Represents the total energy of the system, in kcal / mol; E m&w 、E m&o 、E w&o Respectively represent the energy of mineral and water, mineral and oil, water and oil, and the unit is kcal / mol; E m 、E w、E o They represent the energy of minerals, water and oil respectively, and the unit is kcal / mol.

[0030] In a possible implementation, determining the oil-water wettability of the mineral surface according to the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component includes:

[0031] The oil-water wettability of the mineral surface is determined based on the ratio of the interaction energy between the mineral and water to the interaction energy between the mineral and the crude oil component.

[0032] In a possible implementation, determining the oil-water wettability of the mineral surface according to the ratio of the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component includes:

[0033] ΔE m&w / ΔE m&o The larger the ratio, the more hydrophilic the mineral surface is;

[0034] ΔE m&w / ΔE m&o The smaller the ratio, the more oleophilic the mineral surface is;

[0035] ΔE m&w / ΔE m&o When the ratio is close to 1, it indicates that the mineral surface is neutrally wettable;

[0036] Where, ΔE m&w , ΔE m&o They represent the interaction energy between minerals and water, and the interaction energy between minerals and crude oil components, respectively.

[0037] In a second aspect, an embodiment of the present application provides a device for determining the wettability of a single mineral surface, comprising:

[0038] Model building module, used to build water molecule model, crude oil component model and porous mineral model respectively;

[0039] A loading module, used to load water molecules composed of the water molecule model and crude oil components composed of the crude oil component model into the pores of the mineral model respectively, wherein the water molecules and the crude oil components have the same volume;

[0040] An optimization module, used for optimizing the mineral model loaded with the water molecules and the crude oil components to obtain an optimized system model;

[0041] A dynamics simulation module, used to perform molecular dynamics simulation on the optimized system model to obtain a mineral model containing water molecules and crude oil components in the pores;

[0042] An interaction energy determination module, for determining the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component according to the mineral model containing water molecules and crude oil components in the pores;

[0043] The oil-water wettability determination module is used to determine the oil-water wettability of the mineral surface according to the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component.

[0044] In a third aspect, an embodiment of the present application provides an electronic device, including:

[0045] processor;

[0046] Memory;

[0047] And a computer program, wherein the computer program is stored in the memory, and the computer program includes instructions, and when the instructions are executed by the processor, the electronic device executes any one of the methods described in the first aspect.

[0048] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium includes a stored program, wherein when the program is running, the device where the computer-readable storage medium is located is controlled to execute any one of the methods described in the first aspect.

[0049] By adopting the technical solution provided in the embodiment of the present application, the wettability of different single mineral surfaces can be determined, which improves the previous wettability measurement method of placing minerals and oil droplets in the air. Different temperature conditions can be created to provide parameters for accurately identifying the oil-water wettability of reservoir rock mineral surfaces. The wettability of reservoir rock minerals under geological conditions can also be determined, which is beneficial to characterize the heterogeneity of reservoir wettability. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0051] Figure 1 A schematic flow chart of a method for determining the wettability of a single mineral surface provided in an embodiment of the present application;

[0052] Figure 2 The present application also provides a structural block diagram of a device for determining the wettability of a single mineral surface;

[0053] Figure 3 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0054] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0055] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0056] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0057] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0058] In view of the problems existing in the prior art, the embodiment of the present application provides a method for determining the wettability of a single mineral surface, which can determine the mineral wettability of a single mineral-oil-water three-phase system, can create a temperature environment under formation conditions, and the determination result is closer to the actual underground situation; no experimental samples are required, and the scope of application is wide, and the wettability of any single mineral surface can be determined. The method is described in detail below in conjunction with a specific implementation method.

[0059] See also Figure 1 , is a schematic flow chart of a method for determining the wettability of a single mineral surface provided in an embodiment of the present application. Figure 1 As shown, it mainly includes the following steps.

[0060] Step S101: Establish a water molecule model, a crude oil component model, and a pore-containing mineral model respectively.

[0061] In a specific implementation, the method for establishing a crude oil component model includes: performing group component analysis on the oil produced from the rock reservoir to obtain the crude oil component information contained in the rock sample; selecting the component type with the highest content and its typical hydrocarbon molecules from the crude oil component information to establish a crude oil component model.

[0062] In a specific implementation, establishing a mineral model containing pores includes: selecting a single mineral contained in a rock reservoir, establishing a mineral model containing pores, and the mineral model is a single-layer structure model or a multi-layer structure model. In a possible implementation, the three-dimensional spatial dimensions of the pores of the mineral model are x, y, and z, respectively, where x and y are integer multiples of the length and width of the mineral unit cell, respectively, and x is twice y, and z≥y.

[0063] Step S102: loading water molecules composed of a water molecule model and crude oil components composed of a crude oil component model into the pores of the mineral model respectively, wherein the volumes of the water molecules and the crude oil components are the same.

[0064] Specifically, a water molecule model and a crude oil component model of the same volume are established respectively; along the direction parallel to the surface of the mineral model, the water molecule model and the crude oil component model of the same volume are loaded into the pores of the mineral model respectively, so that the surface of the mineral model is occupied by water molecules and crude oil components respectively, and the surface areas occupied by water molecules and crude oil components are equal. In other words, about 50% of the surface area of ​​the mineral model is occupied by water molecules, and the remaining about 50% of the surface area is occupied by crude oil components. It should be pointed out that the "same" and "equal" involved in the embodiments of the present application are not strictly and absolutely the same and equal. In other words, the "same" and "equal" involved in the embodiments of the present application can be understood as "approximately the same" and "approximately equal".

[0065] Step S103: Optimizing the mineral model loaded with water molecules and crude oil components to obtain an optimized system model.

[0066] Specifically, the mineral model loaded with water molecules and crude oil components is first geometrically optimized. This step can be repeated multiple times (for example, the maximum number of iterations is set to 50,000) until the convergence curve indicates convergence. Secondly, the mineral model after geometry optimization is annealed. In a possible implementation, the annealing cycle is set to 10, the initial temperature is set to 300K, the maximum temperature is set to 1000K, and the NVT ensemble is used to simulate a lower energy system model, that is, to obtain an optimized system model.

[0067] Step S104: performing molecular dynamics simulation on the optimized system model to obtain a mineral model containing water molecules and crude oil components in the pores.

[0068] Specifically, the force field type is set for the optimized system model, and the NVT system is used to apply simulated temperature conditions to perform molecular dynamics simulation to obtain a mineral model containing water molecules and crude oil components in the pores.

[0069] Step S105: According to the mineral model containing water molecules and crude oil components in the pores, the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil components are determined.

[0070] Specifically, according to the formula: ΔE m&w =(E m+o+w -E m&o -E w&o -E m -E w +E o +E m&w ) / 2 calculates the interaction energy between minerals and water; according to the formula: ΔE m&o =(E m+o+w -E m&w -E w&o -E m -E o +E w +E m&o ) / 2 to calculate the interaction energy between minerals and crude oil components; where ΔE m&w , ΔE m&o They represent the interaction energy between minerals and water, and the interaction energy between minerals and crude oil components, respectively, in kcal / mol; E m+o+w Represents the total energy of the system, in kcal / mol; E m&w 、E m&o 、E w&o Respectively represent the energy of mineral and water, mineral and oil, water and oil, and the unit is kcal / mol; E m 、E w 、E o They represent the energy of minerals, water and oil respectively, and the unit is kcal / mol.

[0071] Step S106: Determine the oil-water wettability of the mineral surface according to the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component.

[0072] Specifically, after obtaining the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component, the ratio of the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component ΔE can be calculated. m&w / ΔE m&o , according to ΔE m&w / ΔE m&o The size of determines the oil-water wettability of the mineral surface.

[0073] In one possible implementation, ΔE m&w / ΔE m&o The larger the ratio, the more hydrophilic the mineral surface is; ΔE m&w / ΔE m&oThe smaller the ratio, the more lipophilic the mineral surface is; ΔE m&w / ΔE m&o When the ratio is close to 1, it indicates that the mineral surface is neutrally wettable.

[0074] By adopting the technical solution provided in the embodiment of the present application, the wettability of different single mineral surfaces can be determined, which improves the previous wettability determination method of placing minerals and oil droplets in the air, can create different temperature conditions, provide parameters for accurately identifying the oil-water wettability of reservoir rock mineral surfaces, and can also determine the wettability of reservoir rock minerals under geological conditions. Since this method can create a measurement environment close to geological conditions and can establish corresponding experimental models for crude oil components and mineral components, it is conducive to characterizing the heterogeneity of reservoir wettability.

[0075] For ease of understanding, the method for determining the surface wettability of a single mineral provided in the embodiment of the present application is exemplarily described below using the illite-crude oil-water three-phase system as an example, which mainly includes the following steps.

[0076] Step S201: Establish a water molecule model, a crude oil component model, and a pore-containing mineral model respectively.

[0077] Specifically, the mineral is illite, and the crude oil component is C 19 H 40 , using Materials Studio software to establish illite, C 19 H 40 and water molecule model, in which illite is constructed as a single-molecule layer structure model with pores, and the three-dimensional spatial dimensions of the pores are x=5.22nm, y=2.67nm, z=5.00nm, respectively. Its characteristics are that x and y are integer multiples of the length and width of the illite unit cell, respectively, and x is approximately twice of y.

[0078] Step S202: loading water molecules composed of the water molecule model and crude oil components composed of the crude oil component model into the pores of the mineral model respectively, wherein the volumes of the water molecules and the crude oil components are the same.

[0079] Specifically, we establish C with y as the side length. 19 H 40 Cube model and water molecule cube model, and put the same volume of water and C in the direction parallel to the mineral surface. 19 H 40 into the mineral pores, so that 50% of the surface area of ​​illite is occupied by water molecules and the remaining 50% is occupied by C 19 H 40 occupy.

[0080] Step S203: Optimizing the mineral model loaded with water molecules and crude oil components to obtain an optimized system model.

[0081] Specifically, for filling C 19 H 40 The geometry optimization of the illite pore model with water molecules was performed, and the maximum number of iterations was set to 50000. The convergence curve indicated convergence, and the optimization was ended. Then, the model obtained by geometry optimization was annealed, with the annealing cycle set to 10, the initial temperature set to 300K, the maximum temperature set to 1000K, and the NVT ensemble used to simulate a lower energy system model.

[0082] Step S204: performing molecular dynamics simulation on the optimized system model to obtain a mineral model containing water molecules and crude oil components in the pores.

[0083] Specifically, the force field type was set for the optimized system model, the NVT ensemble was used, the temperature was set to 27 °C, and the molecular dynamics simulation was performed with a simulation time of 1000 ps. 19 H 40 Illite pore model with water molecules.

[0084] Step S205: According to the mineral model containing water molecules and crude oil components in the pores, the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil components are determined.

[0085] Specifically, in order to ensure the reliability of the simulation results, the C 19 H 40 and the distribution model of water molecules, respectively, using the formula: ΔE m&w =(E m+o+w -E m&o -E w&o -E m -E w +E o +E m&w ) / 2 and formula: ΔE m&o =(E m+o+w -E m&w -E w&o -E m -E o +E w +E m&o ) / 2Calculate the ratio of illite to water, illite to C 19 H 40 interaction energy.

[0086] Step S206: Determine the oil-water wettability of the mineral surface according to the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component.

[0087] Specifically, in obtaining illite and water, illite and C 19 H 40 After the interaction energy is calculated, the ratio of the interaction energy between minerals and water to the interaction energy between minerals and crude oil components, ΔE m&w / ΔE m&o , as shown in Table 1.

[0088] Table 1:

[0089]

[0090] According to the results in Table 1, at a temperature of 27°C, the average value of the interaction energy between illite and water is -5451.78 kcal / mol. 19 H 40 The average interaction energy is -37.65 kcal / mol. The interaction energy between illite and water and the interaction energy between illite and C 19 H 40 The ratio of interaction energy ΔE m&w / ΔE m&o The average value is 145.60, indicating hydrophilicity.

[0091] It can be understood that in the embodiments of the present application, the wettability of different single minerals can be determined by changing the temperature, pore size, mineral type, and crude oil component.

[0092] Corresponding to the above-mentioned embodiments, the present application also provides a device for determining the wettability of a single mineral surface.

[0093] See also Figure 2 , which is a structural block diagram of a device for determining the wettability of a single mineral surface provided in this application. Figure 2 As shown, it mainly includes the following modules.

[0094] The model building module 201 is used to respectively build a water molecule model, a crude oil component model and a porous mineral model;

[0095] A loading module 202, for loading water molecules composed of the water molecule model and crude oil components composed of the crude oil component model into the pores of the mineral model respectively, wherein the water molecules and the crude oil components have the same volume;

[0096] The optimization module 203 is used to optimize the mineral model loaded with water molecules and crude oil components to obtain an optimized system model;

[0097] The dynamics simulation module 204 is used to perform molecular dynamics simulation on the optimized system model to obtain a mineral model containing water molecules and crude oil components in the pores;

[0098] The interaction energy determination module 205 is used to determine the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component according to the mineral model containing water molecules and crude oil components in the pores;

[0099] The oil-water wettability determination module 206 is used to determine the oil-water wettability of the mineral surface according to the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component.

[0100] By adopting the technical solution provided in the embodiment of the present application, the wettability of different single mineral surfaces can be determined, which improves the previous wettability determination method of placing minerals and oil droplets in the air, can create different temperature conditions, provide parameters for accurately identifying the surface wettability of oil-water reservoir rock minerals, and can also determine the wettability of reservoir rock minerals under geological conditions. Since this method can create a measurement environment close to geological conditions and can establish corresponding experimental models for crude oil components and mineral components, it is conducive to characterizing the heterogeneity of reservoir wettability.

[0101] It should be pointed out that the specific contents involved in the embodiments of the present application can be found in the description of the above method embodiments, and for the sake of brevity, they will not be repeated here.

[0102] Corresponding to the above embodiment, an embodiment of the present application further provides an electronic device.

[0103] See also Figure 3 , is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Figure 3 As shown, the electronic device 300 may include: a processor 301, a memory 302 and a communication unit 303. These components communicate through one or more buses. Those skilled in the art can understand that the electronic device structure shown in the figure does not constitute a limitation on the embodiments of the present application. It can be a bus structure or a star structure, and can also include more or fewer components than shown in the figure, or combine certain components, or arrange the components differently.

[0104] The communication unit 303 is used to establish a communication channel so that the electronic device can communicate with other devices.

[0105] The processor 301 is the control center of the electronic device. It uses various interfaces and lines to connect various parts of the entire electronic device. It runs or executes software programs and / or modules stored in the memory 302, and calls data stored in the memory to perform various functions of the electronic device and / or process data. The processor can be composed of an integrated circuit (IC), for example, it can be composed of a single packaged IC, or it can be composed of multiple packaged ICs with the same or different functions. For example, the processor 301 can include only a central processing unit (CPU). In the embodiment of the present application, the CPU can be a single computing core or multiple computing cores.

[0106] The memory 302 is used to store the execution instructions of the processor 301. The memory 302 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk.

[0107] When the execution instructions in the memory 302 are executed by the processor 301 , the electronic device 300 is enabled to execute part or all of the steps in the above method embodiment.

[0108] Corresponding to the above embodiment, the embodiment of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium may store a program, wherein when the program is running, the device where the computer-readable storage medium is located may be controlled to perform some or all of the steps in the above method embodiment. In a specific implementation, the computer-readable storage medium may be a disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM).

[0109] Corresponding to the above-mentioned embodiment, the embodiment of the present application further provides a computer program product, which includes executable instructions. When the executable instructions are executed on a computer, the computer executes some or all of the steps in the above-mentioned method embodiment.

[0110] In the embodiments of the present application, "at least one" refers to one or more, and "plurality" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and subsequent associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0111] Those of ordinary skill in the art will appreciate that the various units and algorithm steps described in the embodiments disclosed herein can be implemented in a combination of electronic hardware, computer software, and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0112] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0113] In several embodiments provided in the present application, any function can be stored in a computer-readable storage medium if it is implemented in the form of a software functional unit and sold or used as an independent product. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., and other media that can store program codes.

[0114] The above is only a specific implementation of the present application. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. The protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for determining the wettability of a single mineral surface, characterized in that: include: Establish water molecule model, crude oil component model and porous mineral model respectively; loading water molecules composed of the water molecule model and crude oil components composed of the crude oil component model into the pores of the mineral model respectively, wherein the water molecules and the crude oil components have the same volume; Optimizing the mineral model loaded with the water molecules and the crude oil components to obtain an optimized system model; Performing molecular dynamics simulation on the optimized system model to obtain a mineral model containing water molecules and crude oil components in the pores; Determining the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component according to the mineral model containing water molecules and crude oil components in the pores; The oil-water wettability of the mineral surface is determined based on the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component.

2. The method according to claim 1, characterized in that: Build a crude oil composition model, including: Conduct group component analysis on the oil produced from rock reservoirs to obtain information on the crude oil components contained in the rock samples; The component type with the highest content and typical hydrocarbon molecules therein are selected from the crude oil component information to establish a crude oil component model.

3. The method according to claim 1, characterized in that Establishment of mineral models with pores, including: A single mineral contained in a rock reservoir is selected to establish a mineral model containing pores, wherein the mineral model is a single-molecular-layer structure model or a multi-molecular-layer structure model.

4. The method according to claim 3, characterized in that The three-dimensional spatial dimensions of the pores of the mineral model are x, y, and z, respectively, wherein x and y are integer multiples of the length and width of the mineral unit cell, respectively, and x is twice y, and z≥y.

5. The method according to claim 1, characterized in that The water molecules composed of the water molecule model and the crude oil components composed of the crude oil component model are loaded into the pores of the mineral model respectively, comprising: Establish water molecule models and crude oil component models of the same volume respectively; Along the direction parallel to the surface of the mineral model, the water molecule model and the crude oil component model of the same volume are loaded into the pores of the mineral model respectively, so that the surface of the mineral model is occupied by water molecules and crude oil components respectively, and the surface areas occupied by the water molecules and the crude oil components are equal.

6. The method according to claim 1, characterized in that The step of optimizing the mineral model loaded with the water molecules and the crude oil components to obtain an optimized system model comprises: Performing geometric optimization on the mineral model loaded with the water molecules and the crude oil components; The geometrically optimized mineral model is subjected to annealing simulation to obtain an optimized system model.

7. The method according to claim 1, characterized in that The optimized system model is subjected to molecular dynamics simulation to obtain a mineral model containing water molecules and crude oil components in the pores, including: The force field type is set for the optimized system model, and a simulated temperature condition is applied to perform molecular dynamics simulation to obtain a mineral model containing water molecules and crude oil components in the pores.

8. The method according to claim 1, characterized in that According to the mineral model containing water molecules and crude oil components in the pores, the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil components are determined, including: According to the formula: ΔE m&w =(E m+o+w -E m&o -E w&o -E m -E w +E o +E m&w ) / 2Calculate the interaction energy between minerals and water; According to the formula: ΔE m&o =(E m+o+w -E m&w -E w&o -E m -E o +E w +E m&o ) / 2Calculate the interaction energy between minerals and crude oil components: Where, ΔE m&w , ΔE m&o They represent the interaction energy between minerals and water, and the interaction energy between minerals and crude oil components, respectively, in kcal / mol; E m+o+w Represents the total energy of the system, in kcal / mol; E m&w 、E m&o 、E w&o Respectively represent the energy of mineral and water, mineral and oil, water and oil, and the unit is kcal / mol; E m 、E w 、E o Represents the energy of minerals, water, and oil respectively. The unit is kcal / mol.

9. The method according to claim 1, characterized in that: Determining the oil-water wettability of the mineral surface according to the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component comprises: The oil-water wettability of the mineral surface is determined based on the ratio of the interaction energy between the mineral and water to the interaction energy between the mineral and the crude oil component.

10. The method according to claim 9, characterized in that Determining the oil-water wettability of the mineral surface according to the ratio of the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component comprises: ΔE m&w / ΔE m&o The larger the ratio, the more hydrophilic the mineral surface is; ΔE m&w / ΔE m&o The smaller the ratio, the more oleophilic the mineral surface is; ΔE m&w / ΔE m&o When the ratio is close to 1, it indicates that the mineral surface is neutrally wettable; Where, ΔE m&w , ΔE m&o They represent the interaction energy between minerals and water, and the interaction energy between minerals and crude oil components, respectively.

11. A device for determining the wettability of a single mineral surface, characterized in that include: Model building module, used to build water molecule model, crude oil component model and porous mineral model respectively; A loading module, used to load water molecules composed of the water molecule model and crude oil components composed of the crude oil component model into the pores of the mineral model respectively, wherein the water molecules and the crude oil components have the same volume; An optimization module, used for optimizing the mineral model loaded with the water molecules and the crude oil components to obtain an optimized system model; A dynamics simulation module, used to perform molecular dynamics simulation on the optimized system model to obtain a mineral model containing water molecules and crude oil components in the pores; An interaction energy determination module, for determining the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component according to the mineral model containing water molecules and crude oil components in the pores; The oil-water wettability determination module is used to determine the oil-water wettability of the mineral surface according to the interaction energy between the mineral and water and the interaction energy between the mineral and the crude oil component.

12. An electronic device, characterized in that: include: processor; Memory; And a computer program, wherein the computer program is stored in the memory, and the computer program includes instructions, and when the instructions are executed by the processor, the electronic device executes the method according to any one of claims 1 to 10.

13. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the method according to any one of claims 1 to 10.

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