Injection and production methods and equipment to improve reservoir gas storage rate

Abstract

This invention provides an injection-production method and apparatus for improving the gas storage rate in oil reservoirs, relating to the field of petroleum extraction technology. The oil reservoir is equipped with oil production wells for extracting oil and gas injection wells for injecting gas into the reservoir. The method includes: acquiring the oil layer distribution structure in the reservoir; determining multiple continuous target areas within the oil layer distribution structure and determining the theoretical gas storage capacity of each target area; determining the oil-gas interface location based on the oil layer distribution structure, the corresponding theoretical gas storage capacity of the target areas, and the actual gas injection volume within a preset time; and determining the plugging location of the oil production wells based on the oil-gas interface location. This injection-production method for improving the gas storage rate in oil reservoirs has the advantages of effectively preventing gas channeling, increasing the gas storage rate, and improving crude oil recovery.

Description

Technical Field

[0001] This invention relates to the field of petroleum extraction technology, specifically to an injection and production method for improving reservoir gas storage rate, an injection and production device for improving reservoir gas storage rate, a machine-readable storage medium, and a computer device. Background Technology

[0002] Carbon capture, utilization, storage, and enhanced oil recovery (EOR) are key carbon emission reduction technologies and a breakthrough for achieving a green and low-carbon transformation. While carbon dioxide flooding technology is currently mature, further research is needed on the optimized design technology for synergistic EOR enhancement through carbon dioxide and carbon storage in late-stage, near-abandoned oilfields.

[0003] Water-driven reservoirs in their late stages have undergone decades of water injection development, resulting in high water cut and low recovery rates. A new development model is urgently needed to achieve low-cost, green, and efficient development. Gas-driven development can improve the difficulty of stabilizing oil production and controlling water in reservoirs. However, due to reservoir heterogeneity and the influence of injection-production well networks, gas-driven development exhibits significant directionality. Switching to gas injection can easily lead to gas channeling, causing the gas-driven effect and gas retention rate to fall short of expectations. Summary of the Invention

[0004] The purpose of this invention is to provide an injection and production method and apparatus for improving the gas burial rate of oil reservoirs. This method and apparatus is used to solve the problem that due to the influence of reservoir heterogeneity and injection and production well network, the gas drive direction is obvious, and gas channeling is very likely to occur after switching to gas injection, so that the gas drive effect and gas burial rate cannot reach the expected effect.

[0005] To achieve the above objectives, embodiments of the present invention provide an injection-production method for improving the gas storage rate of an oil reservoir. The oil reservoir is equipped with oil production wells for extracting oil from the reservoir and gas injection wells for injecting gas into the reservoir. The method includes:

[0006] Obtain the distribution structure of oil layers in the reservoir;

[0007] In the oil reservoir, multiple continuous target regions are identified within the oil layer distribution structure, and the theoretical gas reserves in each target region are determined.

[0008] Based on the oil layer distribution structure in the reservoir, the theoretical gas reserves in the corresponding target area, and the actual gas injection volume within a preset time, the location of the oil-gas interface is determined.

[0009] Based on the location of the oil and gas interface, the plugging location of the oil well is determined.

[0010] Optionally, the method further includes:

[0011] Based on the oil layer distribution structure in the reservoir, the locations of gas injection wells and oil production wells are determined; the oil production wells include a plugging section and a production section, with the production section located below the plugging section.

[0012] Optionally, based on the oil layer distribution structure in the reservoir, the locations of gas injection wells and production wells are determined, including:

[0013] The highest point in the vertical direction of the oil layer in the reservoir is taken as the location of the gas injection well;

[0014] Based on the oil layer distribution structure in the reservoir, the location of the production well is determined with the location of the gas injection well as the origin and at a first preset distance.

[0015] Optionally, the gas injection section of the gas injection well is located above the oil production section of the oil production well, and the height difference satisfies the second preset distance.

[0016] Optionally, both the gas injection well and the oil production well are vertical wells; the gas injected into the gas injection well is carbon dioxide.

[0017] Optionally, obtain the oil layer distribution structure in the reservoir, including:

[0018] Obtain the geological structure of the reservoir's location;

[0019] The distribution structure of oil layers in an oil reservoir is determined based on geological structure.

[0020] Optionally, multiple consecutive target regions are determined within the oil layer distribution structure of the reservoir, including:

[0021] Taking the highest point of the oil layer in the reservoir as the origin, the reservoir is divided into multiple continuous segments from top to bottom according to a preset height in the longitudinal direction, which are used as the target area.

[0022] Optionally, determine the theoretical gas reserves for each target area, including:

[0023] Based on the oil-bearing area and corresponding oil layer thickness within each target area, the geological reserves corresponding to each target area are determined by volumetric method.

[0024] Based on the geological reserves and recovery rate of each target area, determine the recoverable reserves of each target area.

[0025] Based on the recoverable reserves and formation water content of each target area, the theoretical gas reserves of each target area are determined.

[0026] Optionally, the recoverable reserves corresponding to each target area can be determined using the following formula:

[0027]

[0028] The theoretical gas reserves for each target area are determined using the following formula:

[0029]

[0030] in, The geological reserves corresponding to each target area; For each target area, the recoverable reserves are defined. For recovery rate; The theoretical gas reserves corresponding to each target area; The density of the crude oil in the reservoir; The corresponding formation water volume for each target area; This represents the volume coefficient of the injected gas.

[0031] A second aspect of the present invention also provides an injection-production device for improving the gas storage rate of an oil reservoir, wherein the oil reservoir is provided with an oil production well for producing oil from the reservoir and a gas injection well for injecting gas into the reservoir, the device comprising:

[0032] The acquisition module is used to acquire the distribution structure of oil layers in the reservoir;

[0033] The first determining module is used to determine multiple consecutive target areas in the oil layer distribution structure of the reservoir and to determine the theoretical gas reserves of each target area.

[0034] The second determining module is used to determine the location of the oil-gas interface based on the oil layer distribution structure in the reservoir, the theoretical gas reserves in the corresponding target area, and the actual gas injection volume within a preset time.

[0035] The third determining module is used to determine the plugging location of the oil well based on the location of the oil and gas interface.

[0036] Optionally, the device further includes:

[0037] The fourth determining module is used to determine the location of the gas injection well and the location of the production well based on the oil layer distribution structure in the reservoir; the production well includes a plugging section and a production section, and the production section is located below the plugging section.

[0038] Optionally, the fourth determining module is specifically used for:

[0039] The highest point in the vertical direction of the oil layer in the reservoir is taken as the location of the gas injection well;

[0040] Based on the oil layer distribution structure in the reservoir, the location of the production well is determined with the location of the gas injection well as the origin and at a first preset distance.

[0041] Optionally, the gas injection section of the gas injection well is located above the oil production section of the oil production well, and the height difference satisfies the second preset distance.

[0042] Optionally, both the gas injection well and the oil production well are vertical wells; the gas injected into the gas injection well is carbon dioxide.

[0043] Optionally, the acquisition module is specifically used for:

[0044] Obtain the geological structure of the reservoir's location;

[0045] The distribution structure of oil layers in an oil reservoir is determined based on geological structure.

[0046] Optionally, the first determining module is specifically used for:

[0047] Taking the highest point of the oil layer in the reservoir as the origin, the reservoir is divided into multiple continuous segments from top to bottom according to a preset height in the longitudinal direction, which are used as the target area.

[0048] Optionally, the first determining module is further configured to:

[0049] Based on the oil-bearing area and corresponding oil layer thickness within each target area, the geological reserves corresponding to each target area are determined by volumetric method.

[0050] Based on the geological reserves and recovery rate of each target area, determine the recoverable reserves of each target area.

[0051] Based on the recoverable reserves and formation water content of each target area, the theoretical gas reserves of each target area are determined.

[0052] Optionally, the recoverable reserves corresponding to each target area can be determined using the following formula:

[0053]

[0054] The theoretical gas reserves for each target area are determined using the following formula:

[0055]

[0056] in, The geological reserves corresponding to each target area; For each target area, the recoverable reserves are defined. For recovery rate; The theoretical gas reserves corresponding to each target area; The density of the crude oil in the reservoir; The corresponding formation water volume for each target area; This represents the volume coefficient of the injected gas.

[0057] A third aspect of the present invention also provides a machine-readable storage medium storing instructions for causing a machine to perform the above-described injection and production method for improving reservoir gas burial rate.

[0058] A fourth aspect of the present invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the above-described injection and production method for improving reservoir gas burial rate.

[0059] This solution identifies multiple continuous target regions within the oil layer distribution structure of the reservoir and determines the theoretical gas reserves in each target region. Based on the oil layer distribution structure, the corresponding theoretical gas reserves in the target regions, and the actual gas injection volume within a preset time, the location of the oil-gas interface is determined. This allows for appropriate sealing operations on the production wells to prevent gas channeling and improve carbon dioxide retention. It also overcomes the drawbacks of water injection development, effectively suppressing water cut increases and removing the water seal effect on crude oil, achieving water control and oil enhancement. Furthermore, it simultaneously improves reservoir recovery and achieves carbon sequestration, resulting in a win-win situation and alleviating carbon emission reduction pressures.

[0060] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0061] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0062] Figure 1 This is a flowchart of the injection and production method for improving reservoir gas storage rate provided by the present invention;

[0063] Figure 2 This is a schematic diagram of the reservoir injection and production structure in the injection and production method provided by the present invention;

[0064] Figure 3 This invention describes the gas-oil interface migration pattern in the injection-production method provided by this invention.

[0065] Figure 4 This is a schematic diagram of the carbon dioxide storage comparison curve in the injection and extraction method provided by the present invention;

[0066] Figure 5 This is a schematic diagram of the injection and production device for improving reservoir gas storage rate provided by the present invention.

[0067] Explanation of reference numerals in the attached figures

[0068] 1-Oil reservoir; 2-Gas injection well; 3-Oil production well;

[0069] 4-Air cap; 5-Crack; 10-Acquisition module;

[0070] 20 - First determination module; 30 - Second determination module; 40 - Third determination module;

[0071] 21 - Gas injection well section; 31 - Oil production well section; 32 - Plugging well section;

[0072] 41-Gas-oil interface. Detailed Implementation

[0073] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0074] In the embodiments of the present invention, unless otherwise stated, directional terms such as "up," "down," "left," and "right" generally refer to the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use.

[0075] The terms “first,” “second,” “third,” etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0076] The terms "parallel" and "perpendicular" do not mean that the components must be absolutely parallel or perpendicular, but rather that they can be slightly tilted. For example, "parallel" simply means that its direction is more parallel than "perpendicular," not that the structure must be completely parallel, but that it can be slightly tilted.

[0077] The terms "horizontal," "vertical," and "sag" do not imply that a component must be absolutely horizontal, vertical, or sagging, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," not that the structure must be completely horizontal, but can be slightly tilted.

[0078] Furthermore, terms like "roughly" and "basically" are used to indicate that the content does not require absolute precision, but rather allows for a certain degree of deviation. For example, "roughly equal" does not simply mean absolute equality; in actual production and operation, achieving absolute "equality" is difficult, and a certain degree of deviation is generally present. Therefore, besides absolute equality, "roughly equal to" also includes the aforementioned situation where a certain degree of deviation exists. Using this as an example, in other cases, unless otherwise specified, terms like "roughly" and "basically" have similar meanings.

[0079] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0080] Figure 1 This is a flowchart of the injection and production method for improving reservoir gas storage rate provided by the present invention; Figure 2 This is a schematic diagram of the reservoir injection and production structure in the injection and production method provided by the present invention; Figure 3 This invention describes the gas-oil interface migration pattern in the injection-production method provided by this invention. Figure 4 This is a schematic diagram of the comparison curve of carbon dioxide storage in the injection and extraction method provided by the present invention.

[0081] like Figure 1-4 As shown, this embodiment provides an injection-production method to improve the gas storage rate of an oil reservoir. The oil reservoir is equipped with oil production wells for producing oil from the reservoir and gas injection wells for injecting gas into the reservoir. The method includes:

[0082] Step 101: Obtain the distribution structure of oil layers in the reservoir;

[0083] Step 102: Determine multiple consecutive target regions in the oil layer distribution structure of the reservoir and determine the theoretical gas reserves in each target region;

[0084] Step 103: Based on the oil layer distribution structure in the reservoir, the theoretical gas reserves in the corresponding target area, and the actual gas injection volume within a preset time, determine the location of the oil-gas interface;

[0085] Step 104: Determine the plugging location of the oil well based on the location of the oil and gas interface.

[0086] Specifically, the oil layer distribution structure includes the approximate location and boundary area of ​​the oil layer. The height of the oil layer distribution is obtained through the cross-sectional diagram of the oil layer distribution structure. Among them, the determination of multiple continuous target areas in the oil layer distribution structure of the reservoir can be based on the actual stratigraphic layer structure or on the same fixed preset depth. Each target area has a top layer and a bottom layer, and the bottom layer and top layer of adjacent target areas overlap. For a specific area, the theoretical gas reserves in that target area are calculated. After a preset time, the actual gas injection volume into the reservoir within that time period is obtained. Since the geological structure corresponding to the oil layer distribution structure does not change significantly, the volumetric method can be used to calculate the affected area corresponding to the current actual gas injection volume, and to determine the relative position of the oil-gas interface within the target area. If the calculated current oil-gas interface position is close to the bottom layer of the target area, the well section of the next adjacent target area is pre-sealed to prevent gas channeling during oil production, achieving a carbon dioxide storage rate of over 95%. If the actual gas injection volume exceeds the theoretical gas reserves in the target area, the excess is included in the next adjacent target area, and the affected area of ​​the excess gas injection volume in that next target area is determined. Figure 4 As shown, the injection and extraction method of the present invention has a higher carbon dioxide burial rate compared with the prior art.

[0087] In this embodiment, as Figure 3 As shown, the preset time is in annual units, and the gas injection volume is adjusted annually according to actual production to control the downward movement rate of the gas-oil interface at 10-50 m / year. The gas-oil interface is the contact surface between the gas cap formed after carbon dioxide is injected into the gas injection well and the formation crude oil. Based on the annual gas injection volume, the proportional relationship between the cumulative gas injection volume of the gas injection well and the burialable amount of carbon dioxide in the reservoir over a certain period can be obtained. This allows for the calculation of the downward movement ratio of the gas-oil interface in the vertical structure, i.e., the downward movement position of the gas-oil interface.

[0088] In another embodiment, the injection-production method for improving reservoir gas burial rate described in this embodiment can be applied to fractured buried hill reservoirs in the mid-to-late stages of waterflood development. First, the current well network structure of the reservoir is investigated, and the vertical depth of the production well sections is understood. Based on the existing well network, the locations of gas injection wells are designed to form a new injection-production well network. The reservoir is vertically segmented, and the geological reserves of the reservoir are also divided by segment. The recoverable reserves of each segment of the reservoir are calculated. Based on the recoverable reserves, the burialable amount of carbon dioxide in the reservoir is calculated. Based on the oil layer distribution structure, annual gas injection volume, and burialable amount of carbon dioxide, the downward displacement position of the gas-oil interface is calculated. Based on the gas-oil interface position, the production well sections are sealed year by year.

[0089] The carbon dioxide flooding method not only utilizes the percolation effect of gas in the matrix and the supercritical fluid properties of carbon dioxide to improve oil recovery, but also solves the drawbacks of water injection development, effectively inhibits the rise in water cut, removes the water seal effect on crude oil, and achieves the effect of controlling water and increasing oil production.

[0090] Furthermore, such as Figure 2 As shown, the method further includes:

[0091] Based on the oil layer distribution structure in the reservoir, the locations of gas injection wells and oil production wells are determined; the oil production wells include a plugging section and a production section, with the production section located below the plugging section.

[0092] Specifically, the plugging section is located above the production section. During the oil production process, as the oil production increases, the oil and gas interface will drop, and the current production section will become the plugging section. Therefore, the plugging section needs to be plugged in advance before the oil and gas interface drops to prevent gas leakage.

[0093] Furthermore, based on the oil layer distribution structure in the reservoir, the locations of gas injection wells and production wells are determined, including:

[0094] The highest point in the vertical direction of the oil layer in the reservoir is taken as the location of the gas injection well;

[0095] Based on the oil layer distribution structure in the reservoir, the location of the production well is determined with the location of the gas injection well as the origin and at a first preset distance.

[0096] Specifically, in this embodiment, since gas accumulates upwards relative to crude oil and water within the gas reservoir, top gas injection is employed, primarily using immiscible displacement. During the injection process, a gas cap is first formed at the highest point of the oil layer in the reservoir's vertical direction, fully utilizing gravity stabilization to displace crude oil through gas expansion, effectively increasing the swept volume. Therefore, the injection well needs to be positioned at the highest point of the oil layer's vertical direction to ensure stability during the injection process. Furthermore, to ensure oil production efficiency, production wells are located on the oil layer at predetermined intervals, with the injection well location as the origin. The number of production wells can be determined based on the actual oil layer distribution structure to improve oil production efficiency.

[0097] In this embodiment, the first preset distance is set to 240-350m, which is the distance in the horizontal direction.

[0098] Furthermore, the gas injection well section is located above the oil production well section of the oil production well, and the height difference satisfies the second preset distance.

[0099] Specifically, the vertical elevation difference between the gas injection well section and the oil production well section is set at 100-150m. By adjusting the spatial position, the rapid gas flow of the oil production well after gas injection is prevented, thereby protecting the gas cap and ensuring the smooth downward movement of the gas-oil interface.

[0100] Furthermore, both the gas injection well and the oil production well are vertical wells; the gas injected into the gas injection well is carbon dioxide.

[0101] Specifically, the gas injected into the reservoir is carbon dioxide. This not only utilizes the osmosis effect of gas in the matrix and the supercritical fluid properties of carbon dioxide to improve the recovery rate, but also solves the drawbacks of water injection development, effectively inhibits the rise in water cut, removes the water seal effect on crude oil, achieves the effect of water control and oil increase, and at the same time solves the pressure of carbon emission reduction.

[0102] Furthermore, obtaining the distribution structure of oil layers in the reservoir includes: obtaining the geological structure of the reservoir's location; and determining the distribution structure of oil layers in the reservoir based on the geological structure.

[0103] Specifically, the geological structure of the reservoir location can be determined by establishing a three-dimensional geological model using previous seismic and well logging data. This is a mature existing technology and will not be elaborated upon here. By identifying the geological structure, the boundaries of the oil-bearing layer can be determined, thereby determining the oil-bearing layer distribution structure.

[0104] Furthermore, multiple continuous target areas are determined in the oil layer distribution structure of the reservoir, including: taking the highest point of the oil layer in the reservoir as the origin, dividing multiple continuous segments in the longitudinal direction from top to bottom according to a preset height, as the target areas.

[0105] Specifically, in this embodiment, the highest point of the oil layer in the reservoir is taken as the origin, which is also the location of the gas injection well. The reservoir is divided vertically from top to bottom according to a preset height, resulting in multiple continuous segments that constitute the target area, each containing an oil layer. Based on gas characteristics, the gas cap is located at the very top, and as the amount of injected gas increases, the gas cap expands downwards from the top target area, sequentially filling the corresponding target area from top to bottom.

[0106] Furthermore, the theoretical gas reserves for each target area are determined, including: calculating the geological reserves for each target area using the volumetric method based on the oil-bearing area and corresponding oil layer thickness within each target area; determining the recoverable reserves for each target area based on the geological reserves and recovery rate; and determining the theoretical gas reserves for each target area based on the recoverable reserves and formation water content.

[0107] Specifically, by obtaining the oil-bearing area and corresponding oil layer thickness within each target region, and calculating using the volumetric method, the geological reserves corresponding to each target region can be determined. These geological reserves are the oil layer distribution structure in the reservoir containing crude oil, water, and other impurities. Based on previous mining data, the crude oil recovery rate can be determined, thereby identifying the recoverable reserves. These recoverable reserves include formation water content. Therefore, when determining the theoretical gas reserves corresponding to each target region, the volume of water needs to be removed to ensure that the theoretical gas reserves obtained for each target region are more accurate.

[0108] More specifically, the volumetric method for calculating oil reserves essentially involves determining the volume occupied by oil within the oil reservoir. Oil is stored in the pore spaces of the reservoir, which also contain a certain amount of water in addition to oil. Therefore, by obtaining geological parameters such as the geometric volume of the reservoir (i.e., the product of the oil-bearing area and the effective thickness), effective porosity, and oil saturation, the geological reserves of underground oil can be calculated.

[0109] Oil reservoirs are buried deep underground, and oil under high temperature and high pressure conditions often dissolves a large amount of natural gas. When crude oil is extracted to the surface, the pressure decreases, and the dissolved natural gas in the oil escapes, thus greatly reducing the volume of the oil.

[0110] To convert underground crude oil volume to surface crude oil volume, the underground crude oil volume must be divided by the petroleum volume factor (the ratio of underground crude oil volume to surface crude oil volume under standard conditions). Petroleum reserves are generally expressed by mass, therefore the surface crude oil volume should be multiplied by the density of petroleum. This yields the basic formula for calculating petroleum reserves using the volumetric method:

[0111]

[0112] N Petroleum geological reserves; A The oil-bearing area; h The average effective thickness; The average effective porosity; This represents the average initial water saturation of the oil reservoir. The average surface crude oil density; This is the average volume factor of the original crude oil;

[0113] The geological reserves of primary dissolved gas in the formation crude oil are calculated using the following formula:

[0114]

[0115] in, Geological reserves of dissolved gases; This represents the original dissolved gas-oil ratio.

[0116] The volumetric method is the primary method for calculating the geological reserves of oilfields. This method is applicable to reservoirs at different exploration and development stages, with varying trap types, reservoir types, and driving mechanisms. The reliability of the calculation results depends on the quantity and accuracy of the data. It yields higher accuracy for large and medium-sized structural reservoirs, but lower accuracy for complex reservoir types.

[0117] Furthermore, the recoverable reserves corresponding to each target area are determined using the following formula:

[0118]

[0119] The theoretical gas reserves for each target area are determined using the following formula:

[0120]

[0121] in, The geological reserves corresponding to each target area; For each target area, the recoverable reserves are defined. For recovery rate; The theoretical gas reserves corresponding to each target area; The density of the crude oil in the reservoir; The corresponding formation water volume for each target area; This represents the volume coefficient of the injected gas.

[0122] Figure 5 This is a schematic diagram of the injection and production device for improving the gas storage rate of oil reservoirs provided by the invention.

[0123] like Figure 5 As shown, a second aspect of the present invention also provides an injection-production device for improving the gas storage rate of an oil reservoir, wherein the oil reservoir is provided with an oil production well for producing oil from the reservoir and a gas injection well for injecting gas into the reservoir, the device comprising:

[0124] Module 10 is used to acquire the distribution structure of oil layers in the reservoir;

[0125] The first determining module 20 is used to determine multiple continuous target areas in the oil layer distribution structure of the reservoir and to determine the theoretical gas reserves of each target area.

[0126] The second determining module 30 is used to determine the location of the oil-gas interface based on the oil layer distribution structure in the reservoir, the theoretical gas burial volume of the corresponding target area, and the actual gas injection volume within a preset time.

[0127] The third determining module 40 is used to determine the plugging location of the oil well based on the location of the oil and gas interface.

[0128] Optionally, the device further includes: a fourth determining module, used to determine the location of the gas injection well and the location of the production well based on the oil layer distribution structure in the reservoir; the production well includes a plugging section and a production section, the production section being located below the plugging section.

[0129] Optionally, the fourth determining module is specifically used to: take the highest point of the oil layer in the reservoir as the location of the gas injection well; and determine the location of the production well based on the distribution structure of the oil layer in the reservoir, with the location of the gas injection well as the origin and at a first preset distance.

[0130] Optionally, the gas injection well section is located above the oil production well section of the oil production well, and the height difference satisfies the second preset distance.

[0131] Optionally, both the gas injection well and the oil production well are vertical wells; the gas injected into the gas injection well is carbon dioxide.

[0132] Optionally, the acquisition module is specifically used to: acquire the geological structure of the reservoir location; and determine the oil layer distribution structure in the reservoir based on the geological structure.

[0133] Optionally, the first determining module is specifically used to: take the highest point of the oil layer in the reservoir as the origin, and divide it into multiple continuous segments from top to bottom in the longitudinal direction according to a preset height, as the target area.

[0134] Optionally, the first determining module is further configured to: calculate and determine the geological reserves corresponding to each target area using the volumetric method based on the oil-bearing area and the corresponding oil layer thickness within each target area; determine the recoverable reserves corresponding to each target area based on the geological reserves and recovery rate of each target area; and determine the theoretical gas reserves corresponding to each target area based on the recoverable reserves and the formation water content of each target area.

[0135] Optionally, the recoverable reserves corresponding to each target area can be determined using the following formula:

[0136]

[0137] The theoretical gas reserves for each target area are determined using the following formula:

[0138]

[0139] in, The geological reserves corresponding to each target area; For each target area, the recoverable reserves are defined. For recovery rate; The theoretical gas reserves corresponding to each target area; The density of the crude oil in the reservoir; The corresponding formation water volume for each target area; This represents the volume coefficient of the injected gas.

[0140] A third aspect of the present invention also provides a machine-readable storage medium storing instructions for causing a machine to perform the above-described injection and production method for improving reservoir gas burial rate.

[0141] A fourth aspect of the present invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the above-described injection and production method for improving reservoir gas burial rate.

[0142] The optional embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above embodiments. Within the scope of the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all fall within the protection scope of the embodiments of the present invention.

[0143] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not describe the various possible combinations separately.

[0144] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a microcontroller, chip, or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0145] Furthermore, various different implementations of the present invention can be combined arbitrarily, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed in the present invention.

Claims

1. A method for improving the gas storage rate in an oil reservoir, wherein the reservoir is equipped with oil production wells for producing oil from the reservoir and gas injection wells for injecting gas into the reservoir, characterized in that, The method includes: Obtain the distribution structure of oil layers in the reservoir; In the oil reservoir, multiple continuous target regions are identified within the oil layer distribution structure, and the theoretical gas reserves in each target region are determined. Based on the oil layer distribution structure in the reservoir, the theoretical gas reserves in the corresponding target area, and the actual gas injection volume within a preset time, the location of the oil-gas interface is determined. Based on the location of the oil and gas interface, the plugging location of the oil well is determined; The method further includes: Based on the oil layer distribution structure in the reservoir, the locations of gas injection wells and oil production wells are determined; the oil production well includes a plugging section and an oil production section, with the oil production section located below the plugging section. Based on the oil layer distribution structure in the reservoir, the locations of gas injection wells and production wells are determined, including: The highest point in the vertical direction of the oil layer in the reservoir is taken as the location of the gas injection well; Based on the oil layer distribution structure in the reservoir, the location of the production well is determined with the location of the gas injection well as the origin and at a first preset distance. Determine the theoretical gas reserves for each target area, including: Based on the oil-bearing area and corresponding oil layer thickness within each target area, the geological reserves corresponding to each target area are determined by volumetric method. Based on the geological reserves and recovery rate of each target area, determine the recoverable reserves of each target area. Based on the recoverable reserves and formation water content of each target area, the theoretical gas reserves of each target area are determined.

2. The injection and production method for improving reservoir gas storage rate according to claim 1, characterized in that, The gas injection well section is located above the oil production well section of the oil production well, and the height difference meets the second preset distance.

3. The injection and production method for improving reservoir gas storage rate according to claim 1, characterized in that, Both the gas injection well and the oil production well are vertical wells; the gas injected into the gas injection well is carbon dioxide.

4. The injection and production method for improving reservoir gas storage rate according to claim 1, characterized in that, Obtain the distribution structure of oil layers in the reservoir, including: Obtain the geological structure of the reservoir's location; The distribution structure of oil layers in an oil reservoir is determined based on geological structure.

5. The injection and production method for improving reservoir gas storage rate according to claim 1, characterized in that, Multiple continuous target regions were identified within the oil layer distribution structure of the reservoir, including: Taking the highest point of the oil layer in the reservoir as the origin, the reservoir is divided into multiple continuous segments from top to bottom according to a preset height in the longitudinal direction, which are used as the target area.

6. The injection and production method for improving reservoir gas storage rate according to claim 1, characterized in that, The recoverable reserves corresponding to each target area are determined using the following formula: The theoretical gas reserves for each target area are determined using the following formula: in, The geological reserves corresponding to each target area; For each target area, the recoverable reserves are defined. For recovery rate; The theoretical gas reserves corresponding to each target area; The density of the crude oil in the reservoir; The corresponding formation water volume for each target area; This represents the volume coefficient of the injected gas.

7. A gas injection and production device for improving the gas storage rate of an oil reservoir, wherein the oil reservoir is provided with an oil production well for producing oil from the reservoir and a gas injection well for injecting gas into the reservoir, characterized in that, The device includes: The acquisition module is used to acquire the distribution structure of oil layers in the reservoir; The first determining module is used to determine multiple consecutive target areas in the oil layer distribution structure of the reservoir and to determine the theoretical gas reserves of each target area. The second determining module is used to determine the location of the oil-gas interface based on the oil layer distribution structure in the reservoir, the theoretical gas reserves in the corresponding target area, and the actual gas injection volume within a preset time. The third determining module is used to determine the plugging location of the oil well based on the location of the oil and gas interface; The device further includes: The fourth determining module is used to determine the location of the gas injection well and the location of the production well based on the oil layer distribution structure in the reservoir; the production well includes a plugging section and a production section, and the production section is located below the plugging section; The fourth determining module is specifically used for: The highest point in the vertical direction of the oil layer in the reservoir is taken as the location of the gas injection well; Based on the oil layer distribution structure in the reservoir, the location of the production well is determined with the location of the gas injection well as the origin and at a first preset distance. The first determining module is further used for: Based on the oil-bearing area and corresponding oil layer thickness within each target area, the geological reserves corresponding to each target area are determined by volumetric method. Based on the geological reserves and recovery rate of each target area, determine the recoverable reserves of each target area. Based on the recoverable reserves and formation water content of each target area, the theoretical gas reserves of each target area are determined.

8. The injection-production device for improving reservoir gas storage rate according to claim 7, characterized in that, The gas injection well section is located above the oil production well section of the oil production well, and the height difference meets the second preset distance.

9. The injection-production device for improving reservoir gas storage rate according to claim 7, characterized in that, Both the gas injection well and the oil production well are vertical wells; the gas injected into the gas injection well is carbon dioxide.

10. The injection-production device for improving reservoir gas storage rate according to claim 7, characterized in that, The acquisition module is specifically used for: Obtain the geological structure of the reservoir's location; The distribution structure of oil layers in an oil reservoir is determined based on geological structure.

11. The injection and production device for improving reservoir gas storage rate according to claim 7, characterized in that, The first determining module is specifically used for: Taking the highest point of the oil layer in the reservoir as the origin, the reservoir is divided into multiple continuous segments from top to bottom according to a preset height in the longitudinal direction, which are used as the target area.

12. The injection-production device for improving reservoir gas storage rate according to claim 7, characterized in that, The recoverable reserves corresponding to each target area are determined using the following formula: The theoretical gas reserves for each target area are determined using the following formula: in, The geological reserves corresponding to each target area; For each target area, the recoverable reserves are defined. For recovery rate; The theoretical gas reserves corresponding to each target area; The density of the crude oil in the reservoir; The corresponding formation water volume for each target area; This represents the volume coefficient of the injected gas.

13. A machine-readable storage medium storing instructions for causing a machine to perform the injection and production method for improving reservoir gas burial rate as described in any one of claims 1-6 of this application.

14. 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, it implements the injection and production method for improving reservoir gas storage rate as described in any one of claims 1-6 of this application.

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