Method, device and equipment for determining minimum miscible pressure of crude oil and gas

Abstract

The invention relates to the technical field of oil and gas field development, in particular to a method, device and equipment for determining the minimum miscible pressure of crude oil and gas. The method for determining the minimum miscible pressure of the crude oil and the gas comprises the following steps: acquiring mass transfer images of different pressure points in a constant-temperature pressurization process after the crude oil and the gas are mixed; according to the mass transfer images of the different pressure points, using a preset mass transfer ring image recognition model to judge state parameters of crude oil and gas of the different pressure points; the state parameters comprise mass transfer ring range parameters; the mass transfer ring represents a circular ring shown in a mass transfer image when the crude oil transfers mass to the gas due to density difference and concentration difference between the crude oil and the gas; and determining the minimum miscible pressure of the crude oil and the gas according to the state parameters of the crude oil and the gas at different pressure points. According to the embodiment of the invention, the minimum miscible pressure of the crude oil and the gas can be efficiently, accurately and quickly determined according to the mass transfer ring range parameters of the crude oil and the gas at different pressure points.

Description

Technical Field

[0001] The embodiments of this specification relate to the technical field of oil and gas field development, and specifically to a method, device, and equipment for determining the minimum miscibility pressure of crude oil and gas. Background Art

[0002] According to the coexistence forms of gas (such as CO 2 , nitrogen, etc.) and crude oil during the displacement process, gas flooding can be divided into miscible flooding and immiscible flooding. Among them, during miscible flooding, the gas and oil will achieve miscibility, the interface between the gas and oil will disappear and dissolve into one phase, and at the same time, the viscosity of the oil will be greatly reduced, which is beneficial to the flow and exploitation of the oil. Theoretically, the oil displacement efficiency tends to 100%. Therefore, gas miscible flooding is an important method for gas to improve oil recovery. However, the gas and crude oil need to reach a certain relatively high pressure to achieve miscibility, and the minimum miscibility pressures of different crude oils and gases are also different. Therefore, how to efficiently and accurately determine the miscibility pressure of gas and crude oil is of great significance for experimental research and practical engineering applications.

[0003] Currently, the common methods for determining the minimum miscibility pressure of gas and crude oil mainly include the slim tube experiment method, the interfacial tension measurement method, and the empirical formula prediction method, etc. These existing methods have provided valuable experience for the determination of the minimum miscibility pressure and the research of gas flooding, but they also have their own limitations. The advantage of the slim tube experiment method is that the operation difficulty of indoor experiments is relatively small and the method is mature; the disadvantage is that the measurement time is long and the accuracy is average. The advantage of the interfacial tension method is high accuracy, but the operation difficulty is large, and it is difficult for conventional laboratories to measure the interfacial tension in high-temperature and high-pressure environments. The advantage of the empirical formula prediction method is that no specific experiments need to be measured, and the disadvantage is low accuracy, and it is necessary to measure oil components, physical property data at different temperatures and pressures, etc.

[0004] Therefore, how to overcome the problems of long test time, low test accuracy, and complex operation existing in the existing methods for determining the minimum miscibility pressure of gas and crude oil, and to propose a method for determining the minimum miscibility pressure of crude oil and gas with short test time, simple and efficient, and high accuracy is a key problem to be solved urgently. Summary of the Invention

[0005] The purpose of the embodiments of this specification is to provide a method, device, and equipment for determining the minimum miscibility pressure of crude oil and gas, so as to overcome the problems of long test time, low accuracy, and complex operation existing in the existing methods for determining the minimum miscibility pressure of gas and crude oil.

[0006] On the one hand, an embodiment of the present specification provides a method for determining the minimum miscibility pressure of crude oil and gas. The method for determining the minimum miscibility pressure of crude oil and gas includes: obtaining mass transfer images at different pressure points during the constant-temperature pressurization process after mixing crude oil and gas; according to the mass transfer images at different pressure points, using a preset mass transfer ring image recognition model to determine the state parameters of crude oil and gas at different pressure points; the state parameters include mass transfer ring range parameters; the mass transfer ring represents a circular ring presented in the mass transfer image when crude oil mass transfers to gas due to the density difference and concentration difference between crude oil and gas; determining the minimum miscibility pressure of crude oil and gas according to the state parameters of crude oil and gas at different pressure points.

[0007] On the other hand, an embodiment of the present specification provides a device for determining the minimum miscibility pressure of crude oil and gas. The device for determining the minimum miscibility pressure of crude oil and gas includes: an obtaining module, configured to obtain mass transfer images at different pressure points during the constant-temperature pressurization process after mixing crude oil and gas; a determining module, configured to use a preset mass transfer ring image recognition model to determine the state parameters of crude oil and gas at different pressure points according to the mass transfer images at different pressure points; the state parameters include mass transfer ring range parameters; the mass transfer ring represents a circular ring presented in the mass transfer image when crude oil mass transfers to gas due to the density difference and concentration difference between crude oil and gas; a determining module, configured to determine the minimum miscibility pressure of crude oil and gas according to the state parameters of crude oil and gas at different pressure points.

[0008] On yet another aspect, a computer device is provided, including a memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor executes the above method for determining the minimum miscibility pressure of crude oil and gas.

[0009] As can be seen from the technical solutions provided by the embodiments of the present specification above, the embodiments of the present specification can obtain mass transfer images at different pressure points during the constant-temperature pressurization process after mixing crude oil and gas; according to the mass transfer images at different pressure points, use a preset mass transfer ring image recognition model to determine the state parameters of crude oil and gas at different pressure points; the state parameters include mass transfer ring range parameters; the mass transfer ring represents a circular ring presented in the mass transfer image when crude oil mass transfers to gas due to the density difference and concentration difference between crude oil and gas; determine the minimum miscibility pressure of crude oil and gas according to the state parameters of crude oil and gas at different pressure points. Compared with the existing methods, the embodiments of the present specification can efficiently, accurately, and quickly determine the minimum miscibility pressure of crude oil and gas according to the mass transfer ring range parameters of crude oil and gas at different pressure points. Description of the Drawings

[0010] To more clearly illustrate the technical solutions in the embodiments of this specification or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art.

[0011] Figure 1 It is a flowchart of a method for determining the minimum miscibility pressure of crude oil and gas provided by an embodiment of this specification;

[0012] Figure 2 It is a schematic diagram of the initial image of Offshore Oil A at 40°C without adding CO 2 at that time;

[0013] Figure 3 It is a schematic diagram of the measurement result of the minimum miscibility pressure of CO 2 and Offshore Oil A at 40°C;

[0014] Figure 4 It is a schematic diagram of the mass transfer image corresponding to the first mass transfer state of CO 2 and Offshore Oil A at 40°C;

[0015] Figure 5 It is a schematic diagram of the mass transfer image corresponding to the second mass transfer state of CO 2 and Offshore Oil A at 40°C;

[0016] Figure 6 It is a schematic diagram of the mass transfer image corresponding to the third mass transfer state of CO 2 and Offshore Oil A at 40°C;

[0017] Figure 7 It is a schematic diagram of the mass transfer image corresponding to the fourth mass transfer state of CO 2 and Offshore Oil A at 40°C;

[0018] Figure 8 It is a schematic diagram of the mass transfer image corresponding to the fifth mass transfer state of CO 2 and Offshore Oil A at 40°C;

[0019] Figure 9 It is a schematic diagram of the structural composition of a device for determining the minimum miscibility pressure of crude oil and gas provided by an embodiment of this specification;

[0020] Figure 10 It is a schematic diagram of the structural composition of a computer device provided by an embodiment of this specification. Detailed implementation manners

[0021] Next, the technical solutions in the embodiments of this specification will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of this specification. Obviously, the described embodiments are only a part of the embodiments of this specification, rather than all the embodiments. Based on the embodiments in this specification, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this specification.

[0022] Figure 1 It is a flowchart of a method for determining the minimum miscibility pressure of crude oil and gas provided by an embodiment of this specification. Specifically in implementation, this method includes the following steps:

[0023] S101: Obtain the mass transfer images at different pressure points during the constant-temperature pressurization process after mixing crude oil and gas.

[0024] In some embodiments, two intermediate containers respectively containing crude oil and gas and a preset constant-temperature visible container can be raised to a preset experimental temperature; after the temperatures of the two intermediate containers respectively containing crude oil and gas and the preset constant-temperature visible container are stabilized at the preset experimental temperature, the oil and gas can be transferred into the constant-temperature visible container.

[0025] By stabilizing the temperatures of the two intermediate containers respectively containing crude oil and gas and the preset constant-temperature visible container at the preset experimental temperature, it can be ensured that relevant equipment and experimental substances reach a thermal equilibrium state, avoiding the influence on the states of crude oil and gas due to temperature changes, and further ensuring the accuracy of experimental data in the subsequent determination process of the minimum miscibility pressure of crude oil and gas.

[0026] The two intermediate containers respectively containing crude oil and gas and the preset constant-temperature visible container can be pre-checked to ensure that these containers are all in good working condition. The sealing performance of the constant-temperature visible container can be checked to ensure that there will be no leakage during the subsequent experiment. The two intermediate containers and the constant-temperature visible container meet the requirements of heat resistance ≥ 40 °C, pressure resistance ≥ 30 Mpa, visibility, having fluid inlets and outlets, and also having a pressure sensor or pressure detection function. The two intermediate containers respectively containing crude oil and gas and the preset constant-temperature visible container can be raised to the preset experimental temperature. For example, for the gas being CO 2 in terms of, the preset experimental temperature needs to enable CO 2Reach the supercritical state, that is, the range of the preset experimental temperature needs to satisfy ≥ 31.06 °C. Considering the experimental difficulty and economy, the preset experimental temperature can be within the range of 35 °C to 50 °C. After raising the temperatures of the two intermediate containers and the constant-temperature visible container to the preset experimental temperature, this state can be maintained for N hours to ensure that these containers and the experimental substances (crude oil and gas) all reach the thermal equilibrium state. N can be a preset positive number. After the temperature stabilizes, the crude oil and gas can be transferred from the intermediate container to the constant-temperature visible container. It is necessary to ensure that the equipment such as pipelines and valves used in the transfer process are cleaned and dried to avoid contaminating the experimental substances.

[0027] In some embodiments, the crude oil and gas are placed in a preset constant-temperature visible container; the constant-temperature visible container can be pressurized at a preset pressurization rate; at every preset fixed pressure interval, a preset image sensor can be used to obtain the mass transfer image of the mixture of the crude oil and gas.

[0028] By obtaining the mass transfer image of the mixture of the crude oil and gas using a preset image sensor at every fixed pressure interval, the mass transfer images of the mixture state of the crude oil and gas at different pressure points can be uniformly obtained, which helps to comprehensively and accurately determine the minimum miscibility pressure of the crude oil and gas based on the mass transfer images at different pressure points.

[0029] For the crude oil and gas placed in the constant-temperature visible container, pressurization can be carried out at a preset pressurization rate. The pressurization method can be continuously injecting gas into the constant-temperature visible container, or keeping the mass of the crude oil and gas in the constant-temperature visible container unchanged and using a piston to reduce the volume. By both of these methods, pressurization of the crude oil and gas in the constant-temperature visible container at a preset pressurization rate can be achieved, which will not be elaborated here. For example, for the gas being CO 2 in this case, the initial pressure in the constant-temperature visible container can be vacuum or atmospheric pressure, and the pressure at the end of the experiment needs to satisfy ≥ 20 Mpa. Considering the experimental difficulty and economy, the pressure at the end of the experiment can be within the range of 20 Mpa to 35 Mpa. The method of continuously injecting CO2 can be used to pressurize the crude oil and CO 2 in the constant-temperature visible container. The pressurization rate can be set to ≤ 2 Mpa / min. During the pressurization process of the crude oil and gas in the constant-temperature visible container, at every preset fixed pressure interval, a preset image sensor can be used to obtain the mass transfer image of the mixture of the crude oil and gas. By obtaining the mass transfer image at every fixed pressure interval, the mass transfer process of the mixture of the crude oil and gas under different pressure conditions can be captured. This helps to understand the mass transfer rate, mass transfer mechanism, and the influence of pressure on the mass transfer process.

[0030] S102: According to the mass transfer images of the different pressure points, use a preset mass transfer loop image recognition model to determine the state parameters of the crude oil and gas at different pressure points; the state parameters include mass transfer loop range parameters; the mass transfer loop represents a circular ring presented in the mass transfer image during the mass transfer of crude oil to gas due to the density difference and concentration difference between the crude oil and gas.

[0031] In some embodiments, the state parameters of the crude oil and gas at different pressure points further include the crude oil volume parameters at different pressure points; the crude oil volume parameters at different pressure points during the constant temperature and pressurization process of the mixture of crude oil and gas can be obtained; according to the mass transfer images of the different pressure points, a preset mass transfer loop image recognition model can be used to generate the mass transfer loop range parameters corresponding to different pressure points.

[0032] By obtaining the crude oil volume parameters at different pressure points, the change trend of the crude oil volume with pressure can be clearly understood. In addition, using a preset mass transfer loop image recognition model to obtain the mass transfer loop range parameters can intuitively understand the mass transfer state of the crude oil and gas with pressure change. Based on the change trend of the crude oil volume with pressure and the mass transfer state of the crude oil and gas with pressure change, the mass transfer situations of the crude oil and gas at different pressures can be accurately classified, which helps to quickly and accurately determine the minimum miscibility pressure between the crude oil and gas.

[0033] The state parameters of crude oil and gas at different pressure points include crude oil volume parameters at different pressure points and mass transfer range parameters of crude oil and gas at different pressure points. The crude oil volume parameters at different pressure points can represent the compressibility and phase change behavior of crude oil under different pressures. A trend curve of crude oil volume parameters changing with pressure can be constructed, and the characteristics related to the minimum miscible pressure of crude oil and gas can be obtained from the trend curve through trend analysis and calculation. The constant temperature visual container can have a built-in volume sensor, and the outer wall of the constant temperature visual container can also be engraved with scale lines. For example, the constant temperature visual container has a built-in volume sensor, and the volume sensor can be used directly to obtain the crude oil volume parameters at different pressure points. For example, the outer wall of the constant temperature visual container is engraved with scale lines, and a scale line recognition model based on a deep learning network can be preset. In the process of pressurizing the crude oil and gas in the constant temperature visual container, the preset scale line recognition model can be used at fixed time intervals to detect the volume value of the crude oil at the current pressure point, and the detected volume value is used as the crude oil volume parameter at the current pressure point. The mass transfer range parameters of crude oil and gas at different pressure points can represent the range size of the area where the visible mass transfer ring is located in the mass transfer image under different pressures. The mass transfer ring can indicate that during the pressurization process, crude oil quickly transfers mass to gas under the action of gas extraction and extraction. When the mass transfer reaches a certain intensity, it becomes visible, and under the action of concentration difference and density difference, it presents a ring shape. The range of the mass transfer ring is a reflection of the intensity of the mass transfer. Several mass transfer rings can be arranged to form a mass transfer belt. The disappearance of the mass transfer ring of crude oil and gas can indicate that the interface between the extracted crude oil and gas disappears, so it becomes invisible. The mass transfer effect always exists, but it is no longer visible. The disappearance of the interface between crude oil and gas means that the crude oil and gas are mixed. According to the mass transfer images at different pressure points, the preset mass transfer ring image recognition model can be used to generate the mass transfer ring range parameters corresponding to different pressure points.

[0034] In some embodiments, a mass transfer loop image recognition model may be constructed based on historical mass transfer images under different mass transfer states of crude oil and gas mixtures.

[0035] By using historical mass transfer images to construct a mass transfer ring image recognition model, the range of the mass transfer ring under different pressures can be quickly and accurately obtained, and then the mass transfer state of crude oil and gas under different pressures can be accurately determined in combination with the crude oil volume parameters under different pressures.

[0036] Historical mass transfer images in different mass transfer states of the crude oil and gas mixture can be obtained. Based on a preset image segmentation model, such as SAM. SAM can recognize various input prompts, determine the content to be segmented in the image, and achieve excellent image segmentation effects for unseen or relatively blurred scenarios, so there is no need to retrain or fine-tune it again. SAM can be used to perform image segmentation on the historical mass transfer images in different mass transfer states of the obtained crude oil and gas mixture, obtain the mass transfer rings in each historical mass transfer image, and calculate the number of pixels occupied by the segmented mass transfer rings as the historical mass transfer ring range parameter label. A mass transfer ring image recognition model can be constructed based on a deep learning network. The deep learning network can be, for example, CNN, ResNet, and GNN, etc. The historical mass transfer images in different mass transfer states of the crude oil and gas mixture can be used as the input of the mass transfer ring image recognition model, and the mass transfer ring image recognition model can predict and output the corresponding historical mass transfer ring range parameters. Minimize the predicted historical mass transfer ring range parameters and the historical mass transfer ring range parameter labels until the mass transfer ring image recognition model converges.

[0037] When any deep learning training or optimization in the above scale line recognition model and mass transfer ring image recognition model is carried out, the update process of the learning rate is as follows:

[0038] During the training process, gradient descent is adopted, and the deep learning model parameters are updated according to the gradient descent algorithm of Newton-Leibniz formula. The calculation formula is:

[0039]

[0040] In the formula, ωj represents the jth parameter of the deep learning / machine learning model, and ωj' is the corresponding updated parameter; λ represents the learning rate of the deep learning / machine learning model, which is used to determine the convergence rate of the deep learning / machine learning model; represents the partial derivative of the loss function F(ωj) with respect to ωj when the deviation between the predicted result and the actual result of the deep learning / machine learning model is known. The deviation between the predicted result and the actual result can be calculated through the loss function; the loss function is usually defined based on methods such as the sum of squared errors, absolute value of errors, or logarithmic loss between the predicted result and the actual result. The deep learning / machine learning model adjusts the values of each parameter in the model through the deviation between the predicted result and the actual result, so that the deviation becomes smaller and smaller.

[0041] In some embodiments, the learning rate can be set to a fixed value, or strategies such as learning rate decay, adaptive learning rate, polynomial learning rate, etc. can be adopted. The idea of learning rate decay is to gradually decrease the learning rate as the training progresses, so as to improve the stability and generalization ability of model training. Adaptive learning rate is a class of strategies that can automatically adjust the learning rate, and can dynamically adjust the learning rate according to the gradient information of the parameters, thereby improving the training speed and performance of the model. The idea of polynomial decay is to decay the learning rate through a polynomial function, so as to gradually reduce the learning rate during training. It can help the model converge better in the later stage of training and improve the generalization ability of the model.

[0042] S103: Determine the minimum miscibility pressure of the crude oil and gas according to the state parameters of the crude oil and gas at the different pressure points.

[0043] In some embodiments, starting from the minimum pressure point, all the pressure points can be traversed; the pressure point being traversed can be used as the current pressure point; according to the state parameters of the crude oil and gas at the current pressure point, the mass transfer state of the crude oil and gas at the current pressure point can be determined.

[0044] By determining the mass transfer state of the crude oil and gas at the current pressure point according to the state parameters of the crude oil and gas at the current pressure point, a data basis is laid for determining the minimum miscibility pressure of the crude oil and gas based on the mass transfer state.

[0045] For all relevant pressure points during the pressurization process, starting from the minimum pressure point, all pressure points can be traversed. The pressure point being traversed can be regarded as the current pressure point. According to the state parameters of the crude oil and gas at the current pressure point, the mass transfer state of the crude oil and gas at the current pressure point can be determined. The mass transfer state can include the first mass transfer state, the second mass transfer state, the third mass transfer state, the fourth mass transfer state, and the fifth mass transfer state. The first mass transfer state indicates that the volume of the crude oil at the current pressure point increases compared to the volume of the crude oil at the previous pressure point, and there is no mass transfer ring in the corresponding mass transfer image at the current pressure point. The first mass transfer state can occur after injecting gas. At this time, the gas dissolves and diffuses into the crude oil, approximately a single mass transfer of gas to the crude oil, and only a small expansion of the crude oil volume occurs. The second mass transfer state indicates that the volume of the crude oil at the current pressure point increases compared to the volume of the crude oil at the previous pressure point, and the mass transfer image corresponding to the current pressure point shows a mass transfer ring compared to the mass transfer image corresponding to the previous pressure point. The second mass transfer state can occur when both the dissolution and diffusion of gas into the crude oil and the dissolution of crude oil into gas and the extraction of crude oil by gas exist simultaneously. At this time, the gas and the crude oil transfer mass to each other, but the mass transfer of gas to the crude oil is the dominant effect, the volume of the crude oil expands, and the color of the upper space in the mass transfer image turns to light gray, and visible mass transfer zones and mass transfer rings are generated. The third mass transfer state indicates that the volume of the crude oil at the current pressure point decreases compared to the volume of the crude oil at the previous pressure point, and the range of the mass transfer ring in the mass transfer image corresponding to the current pressure point increases compared to the range of the mass transfer ring in the mass transfer image corresponding to the previous pressure point. The third mass transfer state can occur when the gas and the crude oil transfer mass to each other, and the mass transfer of crude oil to the gas is the dominant effect and the miscibility is not reached. At this time, the volume of the crude oil stops expanding and starts to decrease after reaching the peak, and the color of the upper space in the mass transfer image turns to dark gray, and the range of the visible mass transfer zones and mass transfer rings increases. The fourth mass transfer state indicates that the volume of the crude oil at the current pressure point decreases compared to the volume of the crude oil at the previous pressure point, and there is no mass transfer ring in the mass transfer image corresponding to the current pressure point compared to the mass transfer image corresponding to the previous pressure point. The fourth mass transfer state can occur when the gas and the crude oil transfer mass to each other, and the mass transfer of crude oil to the gas is the dominant effect and the miscibility is reached. At this time, the volume of the crude oil decreases, and the color of the upper space in the mass transfer image becomes light bright yellow, and the visible mass transfer zones and mass transfer rings disappear. At this time, it represents that the oil-gas interface in the oil-gas contact area disappears, and the mass transfer phenomenon is no longer visible. The corresponding pressure point at this time is the minimum miscibility pressure of the crude oil and gas. The fifth mass transfer state indicates that the volume of the crude oil at the current pressure point decreases compared to the volume of the crude oil at the previous pressure point, and there are no mass transfer rings in both the mass transfer image corresponding to the current pressure point and the mass transfer image corresponding to the previous pressure point. The fifth mass transfer state can occur when the gas and the crude oil transfer mass to each other, and the mass transfer of crude oil to the gas is the dominant effect and for pressures greater than the minimum miscibility pressure. At this time, the volume of the crude oil continues to decrease but the rate of decrease slows down, and the color of the upper space in the mass transfer image becomes dark deep yellow.

[0046] According to the state parameters of crude oil and gas at different pressure points, the mass transfer state of crude oil and gas at different pressure points can be determined; according to the mass transfer state of crude oil and gas at different pressure points, the minimum miscibility pressure of crude oil and gas can be determined.

[0047] In some embodiments, according to the state parameters of crude oil and gas at the current pressure point, the corresponding mass transfer state at the current pressure point can be determined; if the mass transfer state corresponding to the current pressure point is the first mass transfer state, according to the mass transfer states of crude oil and gas at multiple different pressure points after the current pressure point, the minimum miscibility pressure of crude oil and gas can be determined; the first mass transfer state means that the volume of crude oil at the current pressure point increases compared with the volume of crude oil at the previous pressure point, and there is no mass transfer loop in the corresponding mass transfer image at the current pressure point.

[0048] If the mass transfer state corresponding to the current pressure point is the first mass transfer state, it indicates that the current pressure point is far from reaching the minimum miscibility pressure point, and the minimum miscibility pressure of crude oil and gas can be quickly and accurately determined according to the mass transfer states of crude oil and gas at multiple different pressure points after the current pressure point.

[0049] According to the state parameters of crude oil and gas at the current pressure point, it is determined that the current pressure point corresponds to the first mass transfer state. The first mass transfer state means that the volume of crude oil at the current pressure point increases compared with the volume of crude oil at the previous pressure point, and there is no mass transfer loop in the corresponding mass transfer image at the current pressure point. The first mass transfer state can occur after injecting gas. At this time, the gas dissolves and diffuses in the crude oil, approximately a single mass transfer of gas to the crude oil, and only a small expansion of the crude oil volume occurs. Therefore, the current pressure point is far from reaching the minimum miscibility pressure point, and it can continue to traverse to the next pressure point, that is, determine the minimum miscibility pressure of crude oil and gas according to the mass transfer states corresponding to multiple different pressure points after the current pressure point.

[0050] In some embodiments, according to the state parameters of crude oil and gas at the current pressure point, the corresponding mass transfer state at the current pressure point can be determined; if the mass transfer state corresponding to the current pressure point is the second mass transfer state, according to the mass transfer states of crude oil and gas at multiple different pressure points after the current pressure point, the minimum miscibility pressure of crude oil and gas can be determined; the second mass transfer state means that the volume of crude oil at the current pressure point increases compared with the volume of crude oil at the previous pressure point, and the corresponding mass transfer image at the current pressure point shows a mass transfer loop compared with the corresponding mass transfer image at the previous pressure point.

[0051] If the mass transfer state corresponding to the current pressure point is the second mass transfer state, it indicates that the current pressure point still has not reached the minimum miscibility pressure point, and the minimum miscibility pressure of crude oil and gas can be quickly and accurately determined according to the mass transfer states of crude oil and gas at multiple different pressure points after the current pressure point.

[0052] Based on the state parameters of the crude oil and gas at the current pressure point, it is determined that the current pressure point corresponds to the second mass transfer state. The second mass transfer state indicates that the volume of the crude oil at the current pressure point increases compared to the volume of the crude oil at the previous pressure point, and a mass transfer ring appears in the mass transfer image corresponding to the current pressure point compared to the mass transfer image corresponding to the previous pressure point. The second mass transfer state can occur when gas dissolves and diffuses in the crude oil, the crude oil dissolves in the gas, and the crude oil is extracted by the gas simultaneously. At this time, mass transfer occurs between the gas and the crude oil, but the mass transfer from the gas to the crude oil is the dominant effect, the volume of the crude oil expands, and the color of the upper space in the mass transfer image turns light gray, with a visible mass transfer zone and a mass transfer ring generated. Therefore, the current pressure point has not yet reached the minimum miscibility pressure point, and it is possible to continue traversing to the next pressure point, that is, to determine the minimum miscibility pressure of the crude oil and gas based on the mass transfer states corresponding to multiple different pressure points after the current pressure point.

[0053] In some embodiments, based on the state parameters of the crude oil and gas at the current pressure point, the mass transfer state corresponding to the current pressure point can be determined; if the mass transfer state of the crude oil and gas at the current pressure point is the third mass transfer state, based on the mass transfer states of the crude oil and gas at multiple different pressure points after the current pressure point, the minimum miscibility pressure of the crude oil and gas can be determined; the third mass transfer state indicates that the volume of the crude oil at the current pressure point decreases compared to the volume of the crude oil at the previous pressure point, and the range of the mass transfer ring in the mass transfer image corresponding to the current pressure point increases compared to the range of the mass transfer ring in the mass transfer image corresponding to the previous pressure point.

[0054] If the mass transfer state corresponding to the current pressure point is the third mass transfer state, it indicates that the current pressure point is already close to the minimum miscibility pressure point, and the minimum miscibility pressure of the crude oil and gas can be determined quickly and accurately based on the mass transfer states of the crude oil and gas at multiple different pressure points after the current pressure point.

[0055] Based on the state parameters of the crude oil and gas at the current pressure point, it is determined that the current pressure point corresponds to the third mass transfer state. The third mass transfer state indicates that the volume of the crude oil at the current pressure point decreases compared to the volume of the crude oil at the previous pressure point, and the range of the mass transfer ring in the mass transfer image corresponding to the current pressure point increases compared to the range of the mass transfer ring in the mass transfer image corresponding to the previous pressure point. The third mass transfer state can occur when mass transfer occurs between the gas and the crude oil, the mass transfer from the crude oil to the gas is the dominant effect, and miscibility has not been reached. At this time, the volume of the crude oil reaches its peak and then stops expanding and begins to decrease, the color of the upper space in the mass transfer image turns dark gray, and the range of the visible mass transfer zone and the mass transfer ring increases. Therefore, the current pressure point is already close to the minimum miscibility pressure point, and it is possible to continue traversing to the next pressure point, that is, to determine the minimum miscibility pressure of the crude oil and gas based on the mass transfer states corresponding to multiple different pressure points after the current pressure point.

[0056] In some embodiments, according to the state parameters of the crude oil and gas at the current pressure point, the mass transfer state corresponding to the current pressure point can be determined; if the mass transfer state of the crude oil and gas at the current pressure point is the fourth mass transfer state, it can be determined that the pressure value corresponding to the current pressure point is the minimum miscibility pressure of the crude oil and gas; the fourth mass transfer state means that the volume of the crude oil at the current pressure point is smaller than that at the previous pressure point, and there is no mass transfer loop in the mass transfer image corresponding to the current pressure point compared with the mass transfer image corresponding to the previous pressure point.

[0057] If the mass transfer state corresponding to the current pressure point is the fourth mass transfer state, it indicates that the current pressure point is the minimum miscibility pressure point, and the minimum miscibility pressure of the crude oil and gas can be quickly and accurately determined according to the pressure value corresponding to the current pressure point.

[0058] According to the state parameters of the crude oil and gas at the current pressure point, it is determined that the current pressure point corresponds to the fourth mass transfer state. The fourth mass transfer state means that the volume of the crude oil at the current pressure point is smaller than that at the previous pressure point, and there is no mass transfer loop in the mass transfer image corresponding to the current pressure point compared with the mass transfer image corresponding to the previous pressure point. The fourth mass transfer state can occur when the gas and the crude oil are mass-transferring with each other, the mass transfer from the crude oil to the gas is the dominant effect, and miscibility is reached. At this time, the volume of the crude oil decreases, the color of the upper space in the mass transfer image becomes light bright yellow, and the visible mass transfer zone and mass transfer loop disappear. At this time, it represents that the oil-gas interface in the oil-gas contact area disappears and the mass transfer phenomenon is no longer visible. The corresponding pressure point at this time is the minimum miscibility pressure of the crude oil and gas. Therefore, the current pressure point is the minimum miscibility pressure point. The pressure value corresponding to the current pressure point can be used as the minimum miscibility pressure of the crude oil and gas.

[0059] After determining that the pressure value corresponding to the current pressure point is the minimum miscibility pressure of the crude oil and gas, the mass transfer states corresponding to multiple pressure points after the current pressure point are the fifth mass transfer state. The fifth mass transfer state means that the volume of the crude oil at the current pressure point is smaller than that at the previous pressure point, and there is no mass transfer loop in both the mass transfer image corresponding to the current pressure point and the mass transfer image corresponding to the previous pressure point. The fifth mass transfer state can occur when the gas and the crude oil are mass-transferring with each other, the mass transfer from the crude oil to the gas is the dominant effect, and for pressures greater than the minimum miscibility pressure. At this time, the volume of the crude oil continues to decrease but the rate of decrease decreases, and the color of the upper space in the mass transfer image becomes dark deep yellow.

[0060] The following provides a specific embodiment of this specification:

[0061] 1. Select CO at 40 °C 2 and A offshore crude oil as an example. Clean the visible experimental device and pipeline. Place the intermediate container filled with A offshore crude oil and CO 2 in the constant-temperature visible container and raise the temperature to the experimental temperature (40 °C) and stabilize for 5 h. After the temperature is stable, transfer A offshore crude oil and CO2 Transfer to a constant-temperature visible container to obtain the initial crude oil volume parameter and the initial image of Offshore A crude oil without adding CO 2 , and ensure that the temperature remains unchanged. The initial image of Offshore A crude oil without adding CO 2 is as shown in Figure 2 .

[0062] 2. Keep the volume of the constant-temperature visible container constant and continuously inject CO 2 to increase the driving pressure. To ensure the measurement accuracy and safety, the pressurization speed is 0.5 Mpa / min. The mass transfer image is recorded by an industrial camera. The pressure interval for obtaining the mass transfer image and the crude oil volume parameter is 0.1 Mpa. Use the preset scale line recognition model to obtain the crude oil volume parameter. Use the preset mass transfer ring recognition model to obtain the mass transfer ring range parameter from the mass transfer image. The pressure at the end of the experiment is selected as 20 Mpa.

[0063] 3. As shown in Figure 3 the schematic diagram of the minimum miscibility pressure measurement result of CO 2 and Offshore A crude oil. According to the determination methods of the first mass transfer state, the second mass transfer state, the third mass transfer state, the fourth mass transfer state, and the fifth mass transfer state of CO 2 and Offshore A crude oil, determine that the minimum miscibility pressure of CO 2 and Offshore A crude oil is 15.2 Mpa. Figure 4 shows the mass transfer image corresponding to the first mass transfer state of CO 2 and Offshore A crude oil. Figure 5 shows the mass transfer image corresponding to the second mass transfer state of CO 2 and Offshore A crude oil. Figure 6 shows the mass transfer image corresponding to the third mass transfer state of CO 2 and Offshore A crude oil. Figure 7 shows the mass transfer image corresponding to the fourth mass transfer state of CO 2 and Offshore A crude oil. Figure 8 shows the mass transfer image corresponding to the fifth mass transfer state of CO 2 and Offshore A crude oil.

[0064] The method for determining the minimum miscibility pressure of crude oil and gas provided by the embodiments of this specification can obtain the mass transfer images at different pressure points during the isothermal pressurization process after the crude oil and gas are mixed; according to the mass transfer images at different pressure points, use a preset mass transfer ring image recognition model to determine the state parameters of the crude oil and gas at different pressure points; the state parameters include the mass transfer ring range parameter; the mass transfer ring represents a circular ring presented in the mass transfer image when the crude oil mass transfers to the gas due to the density difference and concentration difference between the crude oil and the gas; according to the state parameters of the crude oil and gas at different pressure points, determine the minimum miscibility pressure of the crude oil and gas. Compared with the existing methods, the embodiments of this specification can efficiently, accurately and quickly determine the minimum miscibility pressure of the crude oil and gas according to the mass transfer ring range parameters of the crude oil and gas at different pressure points.

[0065] Based on the above method for determining the minimum miscibility pressure of crude oil and gas, the embodiments of a device for determining the minimum miscibility pressure of crude oil and gas are also proposed in this specification. As Figure 9 shown, the device 900 for determining the minimum miscibility pressure of crude oil and gas may specifically include the following modules:

[0066] An acquisition module 901, which can be used to acquire the mass transfer images at different pressure points during the isothermal pressurization process after the crude oil and gas are mixed.

[0067] A determination module 902, which can be used to determine the state parameters of the crude oil and gas at different pressure points according to the mass transfer images at different pressure points by using a preset mass transfer ring image recognition model; the state parameters include the mass transfer ring range parameter; the mass transfer ring represents a circular ring presented in the mass transfer image when the crude oil mass transfers to the gas due to the density difference and concentration difference between the crude oil and the gas.

[0068] A determination module 903, which can be used to determine the minimum miscibility pressure of the crude oil and gas according to the state parameters of the crude oil and gas at different pressure points.

[0069] In some embodiments, the crude oil and gas are placed in a preset isothermal visible container; the above acquisition module 901 can specifically be used to pressurize the isothermal visible container at a preset pressurization speed; at every preset fixed pressure interval, use a preset image sensor to acquire the mass transfer image of the mixed crude oil and gas.

[0070] In some embodiments, the state parameters of the crude oil and gas at different pressure points further include the crude oil volume parameters at different pressure points; the above determination module 902 can specifically be used to acquire the crude oil volume parameters at different pressure points during the isothermal pressurization process after the crude oil and gas are mixed; according to the mass transfer images at different pressure points, use a preset mass transfer ring image recognition model to generate the mass transfer ring range parameters corresponding to different pressure points.

[0071] In some embodiments, the above determination module 902 may specifically be further configured to construct a mass transfer loop image recognition model based on historical mass transfer images in different mass transfer states of the mixture of crude oil and gas.

[0072] In some embodiments, the above determination module 903 may specifically be configured to determine the mass transfer state corresponding to the current pressure point according to the state parameters of the crude oil and gas at the current pressure point; if the mass transfer state corresponding to the current pressure point is the first mass transfer state, determine the minimum miscibility pressure of the crude oil and gas according to the mass transfer states of the crude oil and gas at multiple different pressure points after the current pressure point; the first mass transfer state means that the volume of the crude oil at the current pressure point increases compared with the volume of the crude oil at the previous pressure point, and there is no mass transfer loop in the corresponding mass transfer image at the current pressure point.

[0073] In some embodiments, the above determination module 903 may specifically be further configured to determine the mass transfer state corresponding to the current pressure point according to the state parameters of the crude oil and gas at the current pressure point; if the mass transfer state corresponding to the current pressure point is the second mass transfer state, determine the minimum miscibility pressure of the crude oil and gas according to the mass transfer states of the crude oil and gas at multiple different pressure points after the current pressure point; the second mass transfer state means that the volume of the crude oil at the current pressure point increases compared with the volume of the crude oil at the previous pressure point, and a mass transfer loop appears in the corresponding mass transfer image at the current pressure point compared with the corresponding mass transfer image at the previous pressure point.

[0074] In some embodiments, the above determination module 903 may specifically be further configured to determine the mass transfer state corresponding to the current pressure point according to the state parameters of the crude oil and gas at the current pressure point; if the mass transfer state of the crude oil and gas at the current pressure point is the third mass transfer state, determine the minimum miscibility pressure of the crude oil and gas according to the mass transfer states of the crude oil and gas at multiple different pressure points after the current pressure point; the third mass transfer state means that the volume of the crude oil at the current pressure point decreases compared with the volume of the crude oil at the previous pressure point, and the range of the mass transfer loop in the corresponding mass transfer image at the current pressure point increases compared with the range of the mass transfer loop in the corresponding mass transfer image at the previous pressure point.

[0075] In some embodiments, the above determination module 903 may specifically be further configured to determine the mass transfer state corresponding to the current pressure point according to the state parameters of the crude oil and gas at the current pressure point; if the mass transfer state of the crude oil and gas at the current pressure point is the fourth mass transfer state, determine the pressure value corresponding to the current pressure point as the minimum miscibility pressure of the crude oil and gas; the fourth mass transfer state means that the volume of the crude oil at the current pressure point decreases compared with the volume of the crude oil at the previous pressure point, and there is no mass transfer loop in the corresponding mass transfer image at the current pressure point compared with the corresponding mass transfer image at the previous pressure point.

[0076] As can be seen from the above, based on the minimum miscibility pressure determination device for crude oil and gas provided in the embodiments of this specification, it is possible to obtain the mass transfer images at different pressure points during the isothermal pressurization process after mixing crude oil and gas; according to the mass transfer images at different pressure points, use a preset mass transfer ring image recognition model to determine the state parameters of crude oil and gas at different pressure points; the state parameters include the mass transfer ring range parameter; the mass transfer ring refers to the ring presented in the mass transfer image when crude oil mass transfers to gas due to the density difference and concentration difference between crude oil and gas; according to the state parameters of crude oil and gas at different pressure points, determine the minimum miscibility pressure of crude oil and gas. Compared with the existing methods, the embodiments of this specification can efficiently, accurately and quickly determine the minimum miscibility pressure of crude oil and gas according to the mass transfer ring range parameters of crude oil and gas at different pressure points.

[0077] It should be noted that the units, devices or modules etc. described in the above embodiments can be specifically implemented by computer chips or entities, or by products with certain functions. For the convenience of description, when describing the above devices, they are divided into various modules according to functions and described separately. Of course, when implementing this specification, the functions of each module can be implemented in the same or multiple software and / or hardware, or the modules implementing the same function can be realized by the combination of multiple sub-modules or sub-units etc. The device embodiments described above are only illustrative. For example, the division of the units is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces, and the indirect couplings or communication connections of the devices or units can be in electrical, mechanical or other forms.

[0078] The embodiments of this specification also provide a computer device for a method of determining the lower limit of permeability contrast, including a processor and a memory for storing processor-executable instructions. When specifically implemented, the processor can execute the following steps according to the instructions: obtain the mass transfer images at different pressure points during the isothermal pressurization process after mixing crude oil and gas; according to the mass transfer images at different pressure points, use a preset mass transfer ring image recognition model to determine the state parameters of crude oil and gas at different pressure points; the state parameters include the mass transfer ring range parameter; the mass transfer ring refers to the ring presented in the mass transfer image when crude oil mass transfers to gas due to the density difference and concentration difference between crude oil and gas; according to the mass transfer ring range parameters of crude oil and gas at different pressure points, determine the minimum miscibility pressure of crude oil and gas.

[0079] In order to be able to complete the above instructions more accurately, refer to Figure 10As shown in the figure, the embodiment of the present specification also provides another specific computer device 1000. Among them, the computer device 1000 includes a network communication port 1001, a processor 1002, and a memory 1003. The above structures are connected by internal cables so that each structure can perform specific data interactions.

[0080] The processor 1002 can specifically be used to obtain the mass transfer images at different pressure points during the constant temperature and pressurization process of the mixture of crude oil and gas; according to the mass transfer images at different pressure points, use a preset mass transfer loop image recognition model to determine the state parameters of the crude oil and gas at different pressure points; the state parameters include the mass transfer loop range parameter; the mass transfer loop refers to a circular ring presented in the mass transfer image when crude oil mass transfers to gas due to the density difference and concentration difference between crude oil and gas; according to the mass transfer loop range parameters of the crude oil and gas at different pressure points, determine the minimum miscibility pressure of the crude oil and gas.

[0081] The memory 1003 can specifically be used to store corresponding instruction programs.

[0082] In this embodiment, the network communication port 1001 can be bound to different communication protocols, so as to send or receive different data virtual ports. For example, the network communication port can be a port responsible for web data communication, or a port responsible for FTP data communication, or a port responsible for mail data communication. In addition, the network communication port can also be a physical communication interface or communication chip. For example, it can be a wireless mobile network communication chip, such as GSM, CDMA, etc.; it can also be a Wifi chip; it can also be a Bluetooth chip.

[0083] In this embodiment, the processor 1002 can be implemented in any suitable manner. For example, the processor can take the form of, for example, a microprocessor or a processor and a computer-readable medium storing computer-readable program code (such as software or firmware) executable by the (micro)processor, logic gates, switches, application specific integrated circuit (ASIC), programmable logic controller, and embedded microcontroller, etc. The present specification does not make any limitations.

[0084] In this embodiment, the memory 1003 includes volatile memory and non-volatile memory. The memory 1003 can include multiple levels. In a digital system, as long as it can store binary data, it can be a memory; in an integrated circuit, a circuit without a physical form but with a storage function is also called a memory, such as RAM, FIFO, etc.; in a system, a storage device with a physical form is also called a memory, such as a memory stick, TF card, etc.

[0085] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0086] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to the embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in one Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0087] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including instruction means that implement the functions specified in one Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0088] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0089] The specific embodiments described above further elaborate on the objectives, technical solutions, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for determining the minimum miscible pressure of crude oil and gas, characterized in that: The method comprises: Obtain mass transfer images of crude oil and gas at different pressure points during constant temperature and pressurization; According to the mass transfer images at different pressure points, the state parameters of the crude oil and gas at different pressure points are determined using a preset mass transfer ring image recognition model; the state parameters include mass transfer ring range parameters; the mass transfer ring represents a circular ring in the mass transfer image when the crude oil transfers mass to the gas due to the density difference and concentration difference between the crude oil and the gas; The minimum miscible pressure of the crude oil and the gas is determined according to the state parameters of the crude oil and the gas at the different pressure points.

2. The method according to claim 1, characterized in that: The crude oil and gas are placed in a preset constant temperature visible container; The method of obtaining mass transfer images at different pressure points during constant temperature pressurization after the crude oil and gas are mixed includes: Pressurizing the constant temperature visual container at a preset pressurization speed; At every preset fixed pressure interval, a preset image sensor is used to acquire a mass transfer image of the crude oil and gas mixture.

3. The method according to claim 1, characterized in that: The state parameters of crude oil and gas at different pressure points also include crude oil volume parameters at different pressure points; The method of determining the state parameters of crude oil and gas at different pressure points using a preset mass transfer ring image recognition model according to the mass transfer images at different pressure points includes: Obtaining crude oil volume parameters at different pressure points during constant temperature pressurization after crude oil and gas are mixed; According to the mass transfer images at different pressure points, a preset mass transfer ring image recognition model is used to generate mass transfer ring range parameters corresponding to different pressure points.

4. The method according to claim 1, characterized in that: The method further comprises: According to the historical mass transfer images under different mass transfer states of crude oil and gas mixture, a mass transfer loop image recognition model is constructed.

5. The method according to claim 1, characterized in that: The step of determining the minimum miscible pressure of crude oil and gas according to the state parameters of crude oil and gas at different pressure points comprises: According to the state parameters of crude oil and gas at the current pressure point, the mass transfer state corresponding to the current pressure point is determined; If the mass transfer state corresponding to the current pressure point is the first mass transfer state, the minimum miscibility pressure of the crude oil and the gas is determined according to the mass transfer states of the crude oil and the gas at multiple different pressure points after the current pressure point; the first mass transfer state indicates that the volume of the crude oil at the current pressure point is increased compared to the volume of the crude oil at the previous pressure point, and there is no mass transfer ring in the mass transfer image corresponding to the current pressure point.

6. The method according to claim 1, characterized in that: The step of determining the minimum miscible pressure of crude oil and gas according to the state parameters of crude oil and gas at different pressure points further comprises: According to the state parameters of crude oil and gas at the current pressure point, the mass transfer state corresponding to the current pressure point is determined; If the mass transfer state corresponding to the current pressure point is the second mass transfer state, the minimum miscible pressure of the crude oil and the gas is determined according to the mass transfer states of the crude oil and the gas at multiple different pressure points after the current pressure point; the second mass transfer state indicates that the volume of the crude oil at the current pressure point is increased compared with the volume of the crude oil at the previous pressure point, and a mass transfer ring appears in the mass transfer image corresponding to the current pressure point compared with the mass transfer image corresponding to the previous pressure point.

7. The method according to claim 1, characterized in that: The step of determining the minimum miscible pressure of crude oil and gas according to the state parameters of crude oil and gas at different pressure points further comprises: According to the state parameters of crude oil and gas at the current pressure point, the mass transfer state corresponding to the current pressure point is determined; If the mass transfer state of the crude oil and gas at the current pressure point is the third mass transfer state, the minimum miscible pressure of the crude oil and gas is determined according to the mass transfer states of the crude oil and gas at multiple different pressure points after the current pressure point; the third mass transfer state indicates that the volume of crude oil at the current pressure point is smaller than that at the previous pressure point, and the range of the mass transfer ring in the mass transfer image corresponding to the current pressure point is larger than that in the mass transfer image corresponding to the previous pressure point.

8. The method according to claim 1, characterized in that: The step of determining the minimum miscible pressure of crude oil and gas according to the state parameters of crude oil and gas at different pressure points further comprises: According to the state parameters of crude oil and gas at the current pressure point, the mass transfer state corresponding to the current pressure point is determined; If the mass transfer state of crude oil and gas at the current pressure point is the fourth mass transfer state, the pressure value corresponding to the current pressure point is determined to be the minimum miscible pressure of crude oil and gas; the fourth mass transfer state indicates that the volume of crude oil at the current pressure point is smaller than that at the previous pressure point, and the mass transfer image corresponding to the current pressure point does not have a mass transfer loop compared to the mass transfer image corresponding to the previous pressure point.

9. A device for determining the minimum miscible pressure of crude oil and gas, characterized in that: The device comprises: An acquisition module, used to acquire mass transfer images at different pressure points during constant temperature and pressurization after crude oil and gas are mixed; A determination module, for determining the state parameters of crude oil and gas at different pressure points according to the mass transfer images at different pressure points by using a preset mass transfer ring image recognition model; the state parameters include mass transfer ring range parameters; the mass transfer ring represents a circular ring presented in the mass transfer image when crude oil transfers mass to gas due to density differences and concentration differences between crude oil and gas; The determination module is used to determine the minimum miscible pressure of the crude oil and the gas according to the state parameters of the crude oil and the gas at different pressure points.

10. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 8 is implemented.

Images