A method and device for evaluating energy storage fracturing effect

Abstract

This paper provides a method and device for evaluating the effect of energy storage fracturing, wherein the method includes: selecting an oil production well with an inner pressure lower than a set pressure in a well group as a test well, and using other oil production wells in the well group except the test well as monitoring wells; a fill well is opened between two adjacent oil production wells in the well group; performing energy storage fracturing and well shut-in on the test well according to the selected energy storage fracturing method; in the process of performing energy storage fracturing and well shut-in on the test well, the pressure values ​​of the test well, monitoring well and fill well in the well group are recorded in real time, and the first time when the fill well first generates a pressure response is recorded; determining the formation pressure evaluation factor, fracture state evaluation factor and oil production evaluation factor of the well group; according to the formation pressure evaluation factor, fracture state evaluation factor and oil production evaluation factor of the well group, the energy storage fracturing effect of the well group is obtained. This paper can guide the selection of suitable energy storage fracturing methods on the oil field with different geological conditions and engineering factors.

Description

Technical Field

[0001] The invention relates to the field of petroleum, and in particular to a method and a device for evaluating energy storage fracturing effect. Background Art

[0002] Nearly two-thirds of my country's oil is stored in low-permeability oil fields. Low-permeability oil fields have poor reservoir properties and low formation pressure coefficients, and water injection is generally used for development. However, it is difficult to establish an injection-production relationship and adjust the well group. Moreover, as the monitoring wells are developed over a long period of time, the formation pressure continues to decline, and the fracturing effect is difficult to maintain, resulting in poor fluid supply capacity, low production and low efficiency in most monitoring wells. The depletion development of tight oil reservoirs also has the problem of insufficient formation energy and rapid production decline in the later period. How to improve formation energy and maintain a reasonable formation pressure has become the main factor restricting the efficient development of low-permeability and tight oil fields. In recent years, energy storage fracturing of oil fields has gradually become a major research direction, which is of great significance to the development of monitoring wells in low-permeability oil fields.

[0003] Existing technologies for evaluating energy storage effects mainly use indoor imbibition experiments to study post-fracturing energy storage and flowback, and numerical simulations to study the impact of energy storage fracturing parameters on development effects, which are often quite different from the actual situation and cannot be applied to actual mines; field-based technologies mostly develop equipment and processes, and lack effective evaluation methods for energy storage fracturing effects based on field tests, especially for ultra-low permeability and tight oil and gas well groups. There is a lack of guidance for energy storage fracturing.

[0004] Therefore, there is an urgent need for an evaluation method for the effect of energy storage fracturing that can be applied on site to guide the selection of appropriate energy storage fracturing methods on site in oil fields with different geological conditions and engineering factors. Summary of the invention

[0005] The purpose of the embodiments of this article is to provide a method and device for evaluating the effect of energy storage fracturing, so as to guide the optimization of suitable energy storage fracturing methods at oil fields with different geological conditions and engineering factors.

[0006] To achieve the above objectives, on the one hand, the embodiments of this invention provide a method for evaluating the effect of energy storage fracturing, comprising:

[0007] An oil production well with an internal pressure lower than a set pressure is selected from the well group as a test well, and other oil production wells except the test well are selected from the well group as monitoring wells; an infill well is opened between two adjacent oil production wells in the well group;

[0008] Performing energy storage fracturing and well shut-in on the test well according to the selected energy storage fracturing method;

[0009] During the process of energy storage fracturing and well soaking of the test well, the pressure values ​​of the test well, monitoring well and infill well in the well group are recorded in real time, and the first time when the infill well first generates pressure response is recorded;

[0010] Determine the formation pressure evaluation factor of the well group according to the pressure values ​​of the test well, the monitoring well and the infill well in the well group, and the volume of the energy storage fracturing fluid when performing energy storage fracturing on the test well;

[0011] Performing fracturing and soaking on the monitoring well;

[0012] During the process of fracturing and soaking the monitoring well, recording the second time when the infill well first generates a pressure response;

[0013] Determine the fracture state evaluation factor of the well group according to the first time when the infill well generates a pressure response for the first time, the position of the infill well, and the pumping speed of the energy storage fracturing fluid when the test well is subjected to energy storage fracturing; the second time when the infill well generates a pressure response for the first time, the position of the infill well, and the pumping speed of the fracturing fluid when the monitoring well is subjected to fracturing;

[0014] Determine the oil production evaluation factor of the well group according to the pressure values ​​of the test wells, monitoring wells and infill wells in the well group, and the oil production after fracturing of the test wells and monitoring wells;

[0015] The energy storage fracturing effect of the well group is obtained according to the formation pressure evaluation factor, the fracture state evaluation factor, and the oil production evaluation factor of the well group.

[0016] Preferably, there are one or more test wells, and the pressure inside the test wells is lower than the pressure inside the monitoring wells;

[0017] If there are multiple test wells, performing energy storage fracturing and well soaking on the test wells according to the selected energy storage fracturing method further includes:

[0018] Arrange the plurality of test wells in order from small to large according to the pressure inside the wells;

[0019] The test well is subjected to energy storage fracturing and well soaking in the sorted order according to the selected energy storage fracturing method.

[0020] Preferably, the selected energy storage fracturing method includes:

[0021] An energy storage fracturing method in which a selected energy storage fluid is used to store energy in a small displacement, and then a selected fracturing fluid is used to perform fracturing in a set displacement, and an energy storage fracturing method in which a selected energy storage fracturing fluid is used to perform direct fracturing in a large displacement; wherein the small displacement is smaller than the set displacement, and the large displacement is larger than the set displacement.

[0022] Preferably, determining the formation pressure evaluation factor of the well group according to the pressure values ​​of the test well, the monitoring well and the infill well in the well group, and the volume of the energy storage fracturing fluid when performing energy storage fracturing on the test well further includes:

[0023] According to the pressure values ​​of the test well, the monitoring well and the infill well in the well group, a stable pressure value of the test well, a stable pressure value of the monitoring well and a stable pressure value of the infill well are obtained;

[0024] According to the stable pressure value of the test well, the stable pressure value of the monitoring well and the stable pressure value of the infill well, an average pressure value of the well group is obtained;

[0025] Obtaining a formation pressure increase amplitude according to a difference between an average pressure value of the well group and an initial formation pressure value of the well group;

[0026] Obtaining an energy storage coefficient according to the formation pressure increase amplitude and the volume of energy storage fracturing fluid when performing energy storage fracturing on the test well;

[0027] The formation pressure increase amplitude and the energy storage coefficient are determined as the formation pressure evaluation factors of the well group.

[0028] Preferably, the determining of the fracture state evaluation factor of the well group according to the first time when the infill well generates a pressure response for the first time, the position of the infill well, and the pumping speed of the energy storage fracturing fluid when the test well is subjected to energy storage fracturing; the second time when the infill well generates a pressure response for the first time, the position of the infill well, and the pumping speed of the fracturing fluid when the monitoring well is subjected to fracturing further comprises:

[0029] According to the first time when the infill well first generates a pressure response and the pumping speed of the energy storage fracturing fluid when performing energy storage fracturing on the test well, a first response amount of the first pressure response generated by the infill well is calculated;

[0030] According to the first time when the infill well first generates a pressure response and the position of the infill well, a fracture diffusion coefficient of the corresponding test well is obtained;

[0031] According to the second time when the infill well first generates a pressure response and the pumping speed of the fracturing fluid when the monitoring well is fracturing, a second response amount of the infill well first generating a pressure response is calculated;

[0032] According to the second time when the infill well first generates a pressure response and the position of the infill well, a fracture diffusion coefficient of the corresponding monitoring well is obtained;

[0033] The first response amount of the first pressure response generated by the infill well and the fracture diffusion coefficient of the corresponding test well, the second response amount of the first pressure response generated by the infill well and the fracture diffusion coefficient of the corresponding monitoring well are determined as the fracture state evaluation factors of the well group.

[0034] Preferably, the first response amount or the second response amount of the first pressure response generated by the infill well is calculated by the following formula:

[0035] Q = qt;

[0036] Among them, Q is the first response amount or the second response amount of the first pressure response generated by the infill well, q is the pumping speed of the energy storage fracturing fluid when the test well is subjected to energy storage fracturing or the pumping speed of the fracturing fluid when the monitoring well is subjected to fracturing, and t is the first time or the second time when the infill well first generates a pressure response.

[0037] Preferably, the crack diffusion coefficient is calculated by the following formula:

[0038]

[0039] Among them, D k is the fracture diffusion coefficient of the test well or monitoring well, L is the distance between the location of the infill well and the location of the corresponding test well or monitoring well, and t is the first time or the second time when the infill well first generates a pressure response.

[0040] Preferably, determining the oil production evaluation factor of the well group according to the pressure values ​​of the test wells, monitoring wells and infill wells in the well group, and the post-fracture oil production of the test wells and monitoring wells further comprises:

[0041] According to the pressure values ​​of the test well, the monitoring well and the infill well in the well group, a stable pressure value of the test well, a stable pressure value of the monitoring well and a stable pressure value of the infill well are obtained;

[0042] According to the stable pressure value of the test well, the stable pressure value of the monitoring well and the stable pressure value of the infill well, an average pressure value of the well group is obtained;

[0043] Obtaining a formation pressure increase amplitude according to a difference between an average pressure value of the well group and an initial formation pressure value of the well group;

[0044] Obtaining a production increase coefficient according to the formation pressure increase amplitude and the oil production of the test well and the monitoring well after fracturing;

[0045] The production increase coefficient is determined as the oil production evaluation factor of the well group.

[0046] Preferably, it also includes:

[0047] Selecting another monitoring well from outside the well group, wherein the distance between the other monitoring well and the test well is less than the set distance;

[0048] Opening other infill wells between the other monitoring wells and the adjacent oil production wells;

[0049] Performing fracturing and soaking on the other monitoring wells;

[0050] During the fracturing and soaking process of the other monitoring wells, recording the time when the other infill wells first generate pressure response;

[0051] The fracture state of the other monitoring wells under the influence of the test well is determined according to the time when the other infill wells first generate pressure response, the location of the other infill wells, and the pumping speed of the fracturing fluid when fracturing the other monitoring wells.

[0052] On the other hand, the embodiments of this invention also provide an energy storage fracturing evaluation device, the device comprising:

[0053] A selection module is used to select a well with an internal pressure lower than a set pressure in the well group as a test well, and to select other wells in the well group except the test well as monitoring wells; an infill well is opened between two adjacent wells in the well group;

[0054] An energy storage fracturing module, used for performing energy storage fracturing and well soaking on the test well according to a selected energy storage fracturing method;

[0055] A first recording module is used to record the pressure values ​​of the test well, the monitoring well and the infill well in the well group in real time during the process of energy storage fracturing and well soaking of the test well, and to record the first time when the infill well first generates a pressure response;

[0056] A first determination module is used to determine the formation pressure evaluation factor of the well group according to the pressure values ​​of the test well, the monitoring well and the infill well in the well group, and the volume of the energy storage fracturing fluid when the test well is subjected to energy storage fracturing;

[0057] A fracturing module, used for fracturing and soaking the monitoring well;

[0058] A second recording module is used to record the second time when the infill well first generates a pressure response during the process of fracturing and soaking the monitoring well;

[0059] A second determination module is used to determine the fracture state evaluation factor of the well group according to the first time when the infill well first generates a pressure response, the position of the infill well, and the pumping speed of the energy storage fracturing fluid when the test well is subjected to energy storage fracturing; the second time when the infill well first generates a pressure response, the position of the infill well, and the pumping speed of the fracturing fluid when the monitoring well is subjected to fracturing;

[0060] A third determination module is used to determine the oil production evaluation factor of the well group according to the pressure values ​​of the test wells, monitoring wells and infill wells in the well group, and the oil production after fracturing of the test wells and monitoring wells;

[0061] The effect determination module is used to obtain the energy storage fracturing effect of the well group according to the formation pressure evaluation factor, the fracture state evaluation factor, and the oil production evaluation factor of the well group.

[0062] It can be seen from the technical solution provided in the above embodiments of the present invention that, after performing energy storage fracturing and shut-in on the test well according to the selected energy storage fracturing method, the embodiments of the present invention can obtain the formation pressure evaluation factor, fracture state evaluation factor and oil production evaluation factor of the well group, and evaluate the energy storage fracturing effect of the well group after performing energy storage fracturing and shut-in on the test well from the above three aspects, and the energy storage fracturing effect is for the selected energy storage fracturing method. The energy storage fracturing effects of the well group corresponding to the energy storage fracturing and shut-in of the test well by different energy storage fracturing methods are different, which can further guide the oil field to select a suitable energy storage fracturing method.

[0063] In order to make the above and other purposes, features and advantages of this article more obvious and easy to understand, the following specifically cites preferred embodiments and describes them in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] In order to more clearly illustrate the technical solutions in the embodiments of this article or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of this article. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0065] Figure 1 A schematic flow chart of a method for evaluating the effect of energy storage fracturing provided in an embodiment of this invention is shown;

[0066] Figure 2 A schematic diagram of a well group provided in an embodiment of this invention is shown;

[0067] Figure 3 A schematic diagram of a process of performing energy storage fracturing and well soaking on a test well according to a selected energy storage fracturing method provided in an embodiment of the present invention is shown;

[0068] Figure 4 A schematic diagram of a process for determining a formation pressure evaluation factor of a well group provided in an embodiment of the present invention is shown;

[0069] Figure 5 A schematic diagram of a process for determining a fracture state evaluation factor of a well group provided in an embodiment of this invention is shown;

[0070] Figure 6 A schematic diagram of a process for determining an oil production evaluation factor of a well group provided in an embodiment of the present invention is shown;

[0071] Figure 7 A schematic diagram of a process for evaluating the influence of a test well on the energy storage fracturing effect of other monitoring wells outside the well group under a selected energy storage fracturing mode provided in an embodiment of the present invention is shown;

[0072] Figure 8 A schematic diagram of the module structure of an energy storage fracturing effect evaluation device provided in an embodiment of this invention is shown;

[0073] Fig. 9 A schematic diagram of the structure of a computer device provided in an embodiment of this invention is shown.

[0074] Description of the accompanying symbols:

[0075] 1. Oil wells;

[0076] 2. Infill wells;

[0077] 100. Select module;

[0078] 200. Energy storage fracturing module;

[0079] 300, first recording module;

[0080] 400, first determination module;

[0081] 500, fracturing module;

[0082] 600, second recording module;

[0083] 700, second determination module;

[0084] 800, third determination module;

[0085] 900, effect determination module;

[0086] 902. Computer equipment;

[0087] 904, processor;

[0088] 906. Memory;

[0089] 908, driving mechanism;

[0090] 910, input / output module;

[0091] 912. Input device;

[0092] 914. Output device;

[0093] 916. Presentation equipment;

[0094] 918. Graphical user interface;

[0095] 920, network interface;

[0096] 922, communication link;

[0097] 924. Communication bus. DETAILED DESCRIPTION

[0098] The following will be combined with the drawings in the embodiments of this article to clearly and completely describe the technical solutions in the embodiments of this article. Obviously, the described embodiments are only part of the embodiments of this article, not all of the embodiments. Based on the embodiments of this article, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this article.

[0099] In recent years, the injection of different energy storage media through fracturing has gradually become a major research direction, which is of great significance to the development of monitoring wells in low permeability oil fields.

[0100] At present, various energy storage media that can be injected are proposed, such as clean water, sewage, natural gas, CO 2 、N 2 etc., and due to differences in geological conditions and engineering factors, the energy storage effects of the same energy storage medium are different. Existing technologies for evaluating energy storage effects mainly use indoor imbibition experiments to study energy storage and flowback after fracturing, and numerical simulations to study the impact of energy storage fracturing parameters on development effects, which are often quite different from the actual situation and cannot be applied to actual mines; field-based technologies mostly develop equipment and processes, and lack effective evaluation methods for energy storage fracturing effects based on field tests, especially for ultra-low permeability and tight oil and gas well groups. There is a lack of guidance for energy storage fracturing.

[0101] In order to solve the above problems, the embodiments of this article provide a method for evaluating the effect of energy storage fracturing. Figure 1 This is a flow chart of a method for evaluating the effect of energy storage fracturing provided in the embodiments of this article. This specification provides the method operation steps described in the embodiments or flow charts, but more or fewer operation steps may be included based on conventional or non-creative labor. The order of steps listed in the embodiments is only one way of executing the order of many steps and does not represent the only execution order. When the system or device product is executed in practice, it can be executed in the order of the method shown in the embodiments or the drawings or in parallel.

[0102] It should be noted that the terms "first", "second", etc. in the specification and claims of this article and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of this article described here can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, device, product or equipment that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0103] Reference Figure 1 , which is a method for evaluating the effect of energy storage fracturing shown in this article, comprising:

[0104] S101: selecting an oil production well whose internal pressure is lower than a set pressure in the well group as a test well, and selecting other oil production wells in the well group except the test well as monitoring wells; an infill well is opened between two adjacent oil production wells in the well group;

[0105] S102: performing energy storage fracturing and well soaking on the test well according to the selected energy storage fracturing method;

[0106] S103: During the process of energy storage fracturing and well soaking of the test well, the pressure values ​​of the test well, the monitoring well and the infill well in the well group are recorded in real time, and the first time when the infill well first generates a pressure response is recorded;

[0107] S104: determining a formation pressure evaluation factor of the well group according to the pressure values ​​of the test well, the monitoring well and the infill well in the well group, and the volume of the energy storage fracturing fluid when performing energy storage fracturing on the test well;

[0108] S105: fracturing and soaking the monitoring well;

[0109] S106: During the process of fracturing and soaking the monitoring well, recording the second time when the infill well first generates a pressure response;

[0110] S107: Determine a fracture state evaluation factor of the well group according to the first time when the infill well generates a pressure response for the first time, the position of the infill well, and the pumping speed of the energy storage fracturing fluid when the test well is subjected to energy storage fracturing; the second time when the infill well generates a pressure response for the first time, the position of the infill well, and the pumping speed of the fracturing fluid when the monitoring well is subjected to fracturing;

[0111] S108: determining an oil production evaluation factor of the well group according to the pressure values ​​of the test wells, monitoring wells and infill wells in the well group, and the oil production of the test wells and monitoring wells after fracturing;

[0112] S109: Obtaining the energy storage fracturing effect of the well group according to the formation pressure evaluation factor, the fracture state evaluation factor, and the oil production evaluation factor of the well group.

[0113] Reference Figure 2 is a schematic diagram of a well group. The well group is a real well group under field conditions. The well group includes oil production wells 1 and infill wells 2. The distribution of infill wells 2 has a certain regularity: infill wells 2 are located between two adjacent oil production wells 1, and the distance between infill wells 2 and the two adjacent oil production wells 1 is equal. Generally speaking, Figure 2 A water injection well can be opened at the center of the well group shown. Water injection development is generally used for low permeability reservoirs and is an early development method. In recent years, with the popularization of energy storage fracturing technology, it is not necessary to target water injection development well groups. For unconventional oil reservoirs (tight oil and gas, shale oil and gas), water injection development is not used, but natural depletion development is used.

[0114] For infill wells, a low-compressibility fluid (such as completion brine) needs to be injected into the wellbore of the infill well before the wellhead is sealed, wherein the compressibility of the low-compressibility fluid needs to be lower than the set compressibility, and a wellbore pressure monitoring device is installed for the infill well, wherein the wellbore pressure monitoring device can be a pressure sensor to monitor the pressure in the wellbore. For oil production wells, a pressure sensor is installed at the wellhead or the bottom of the well. Regardless of whether the pressure sensor is installed at the wellhead or the bottom of the well, the purpose is to monitor the bottomhole pressure. Even if it is installed at the wellhead, the bottomhole pressure can be calculated.

[0115] It should be noted that the purpose of monitoring by the wellbore pressure monitoring device and the pressure sensor in this article is to monitor the formation pressure, but the wellbore structures of the infill well and the oil production well are different. For the infill well, since the wellbore in the infill well is a wellbore with a sealed bottom, the formation pressure cannot be measured directly. It is necessary to use the wellbore pressure monitoring device to monitor the pressure changes caused by the deformation of the low-compressibility fluid in the wellbore to convert the formation pressure; but for the oil production well, the bottom of the wellbore of the oil production well is not sealed, and the formation pressure can be obtained by monitoring the wellhead pressure or bottom hole pressure through a pressure sensor.

[0116] Among them, oil wells with well pressure lower than the set pressure are identified as having too low well pressure. The reason for the too low well pressure may be that the reservoir itself is a low-pressure reservoir, or it may be due to formation pressure deficit after the initial production.

[0117] In the well group, an oil-producing well with an internal pressure lower than the set pressure is selected as a test well. The test well is subjected to energy storage fracturing and well soaking according to the selected energy storage fracturing method. During the energy storage fracturing and well soaking process of the test well, the pressure values ​​of the test well, monitoring well and infill well in the well group are recorded in real time. The pressure value here refers to the formation pressure value. As mentioned above, the test well and the monitoring well are both oil-producing wells, so the pressure value is directly monitored by the pressure sensor. For the infill well, the deformation of the low-compressibility fluid needs to be monitored by the wellbore pressure monitoring device, and then the pressure value is converted.

[0118] The specific conversion method is:

[0119] 1. The wellbore of the infill well is completely sealed by a low-compressibility fluid. The wellbore is filled with a low-compressibility fluid. When the low-compressibility fluid is compressed and the volume changes, it will cause a small but recognizable pressure change. The pressure value of the infill well is:

[0120]

[0121] 2. The wellbore of the infill well is not filled with low-compressibility fluid. In the wellbore of the infill well where the liquid level of the low-compressibility fluid is lower than the ground, the wellbore pressure monitoring device is located below the liquid level of the low-compressibility fluid to monitor the change in hydrostatic pressure caused by the rise in the liquid level of the low-compressibility fluid. It is 1 to 2 orders of magnitude smaller than the pressure change when the wellbore is completely sealed by the low-compressibility fluid. The pressure value of the infill well is:

[0122]

[0123] Among them, dP out is the pressure value of the infill well, dP in is the change in wellbore pressure measured by the wellbore pressure monitoring device (caused by the compression of the low-compressibility fluid in the wellbore or the rise of the liquid level), α out is the inner diameter of the wellbore of the infill well, β out is the outer diameter of the wellbore of the infill well, c is the compressibility of the low-compressibility fluid, D H The depth of the wellbore, E is the Young's modulus of the wellbore material of the infill well, L c The length of casing required to apply a given external pressure to produce a specific internal pressure change may be the length of the production casing, which is the casing in contact with the reservoir, and p is the density of the low-compressibility fluid.

[0124] During the process of energy storage fracturing and well soaking in the test well, in addition to real-time recording of the pressure values ​​of the test well, monitoring well and infill well in the well group, it is also necessary to record the first time when the infill well generates pressure response for the first time. Generally speaking, whether it is a test well, a monitoring well or an infill well, its pressure value first rises and then decreases until it stabilizes to a stable value. Taking a monitoring well A as an example, the process of the pressure value of monitoring well A rising is that the cracks generated by the energy storage fracturing and well soaking of the test well are extending, and the pressure wave is transmitted to monitoring well A. After the well soaking starts, the pressure drops, and the pressure value of monitoring well A will stabilize to a stable value. For the infill well, the first time when the pressure response is generated for the first time refers to the time from the beginning of the cracks in the test well to the time when the cracks reach the infill well.

[0125] According to the pressure values ​​of the test wells, monitoring wells and infill wells in the well group, the formation pressure evaluation factor of the well group is determined. Then, the monitoring wells need to be fractured and well-simmered. There may be one or more monitoring wells. When fracturing and well-simmering the monitoring wells, they can be sorted from small to large according to the pressure values ​​in the monitoring wells. Fracturing and well-simmering can be performed one by one. For monitoring wells with pressure response in the test wells, according to the amplitude of the pressure response, monitoring wells with amplitudes greater than the amplitude threshold do not need to be stored, and can be directly fractured and well-simmered. Monitoring wells with amplitudes less than or equal to the amplitude threshold or monitoring wells without pressure response can be used as alternative test wells, and alternative test wells can be subjected to energy storage fracturing. In addition, the energy storage fracturing can be carried out separately. For some test wells or monitoring wells, if the initial transformation volume meets the demand, but the formation pressure drops due to long-term production, only energy storage can be performed according to the actual situation without repeated fracturing.

[0126] During the fracturing and soaking process of the monitoring well, the second time when the infill well first generates pressure response is recorded. The second time when the first pressure response is generated refers to the time from the beginning of the crack in the monitoring well to the time when the crack reaches the infill well, thereby determining the fracture status evaluation factor of the well group.

[0127] The oil production evaluation factor of the well group can be determined based on the pressure values ​​of the test well, monitoring well and infill well, as well as the oil production of the test well and monitoring well after fracturing. The energy storage fracturing effect of the well group can be further obtained based on the formation pressure evaluation factor, fracture state evaluation factor and oil production evaluation factor of the well group.

[0128] Through the method of this paper, after the test well is subjected to energy storage fracturing and well shut-in according to the selected energy storage fracturing method, the formation pressure evaluation factor, fracture state evaluation factor and oil production evaluation factor of the well group can be obtained. The energy storage fracturing effect of the well group after the test well is subjected to energy storage fracturing and well shut-in is evaluated from the above three aspects. The energy storage fracturing effect is for the selected energy storage fracturing method. The energy storage fracturing effects of the well group corresponding to the energy storage fracturing and well shut-in of the test well subjected to energy storage fracturing and well shut-in of the test well by different energy storage fracturing methods are different, which can further guide the oil field to select the appropriate energy storage fracturing method.

[0129] In the embodiment of this article, there are one or more test wells, and the pressure inside the test wells is lower than the pressure inside the monitoring wells;

[0130] Reference Figure 3 If there are multiple test wells, performing energy storage fracturing and well soaking on the test wells according to the selected energy storage fracturing method further includes:

[0131] S201: sorting the plurality of test wells in ascending order according to the pressure inside the wells;

[0132] S202: performing energy storage fracturing and well soaking on the test well in the sorted order according to the selected energy storage fracturing method.

[0133] Assuming that the well pressures of any two or more test wells among multiple test wells are approximately the same, the test wells with approximately the same well pressures can be subjected to energy storage fracturing and well soaking at the same time. Although performing energy storage fracturing and well soaking at the same time can improve work efficiency, it is necessary to further determine which test well specifically generates the pressure response when the encrypted well first generates the pressure response. Therefore, it is preferred to perform energy storage fracturing and well soaking on the test wells one by one in sorted order.

[0134] In the embodiment of this article, the selected energy storage fracturing method includes:

[0135] An energy storage fracturing method in which a selected energy storage fluid is used to store energy in a small displacement, and then a selected fracturing fluid is used to perform fracturing in a set displacement, and an energy storage fracturing method in which a selected energy storage fracturing fluid is used to perform direct fracturing in a large displacement; wherein the small displacement is smaller than the set displacement, and the large displacement is larger than the set displacement.

[0136] The energy storage fracturing method of small-displacement energy storage followed by set-displacement fracturing is specifically as follows: first inject the selected energy storage fluid into the test well at a small displacement, and then inject the selected fracturing fluid into the test well at a set displacement after the pressure or storage amount of the test well reaches the expected value. During the small-displacement energy storage period, no obvious cracks will be generated in the test well, and injecting the selected fracturing fluid at a set displacement will cause cracks in the test well. It should be noted that the selected energy storage fluid and the selected fracturing fluid may be the same or different.

[0137] The specific method of large-volume direct fracturing is to directly inject the selected energy-storage fracturing fluid into the test well at a large displacement. The large-volume injection of the selected energy-storage fracturing fluid will cause cracks in the core.

[0138] Furthermore, the two energy storage fracturing methods can correspond to multiple displacements. For example, the energy storage fracturing method of small-displacement energy storage followed by set-displacement fracturing may include: A-displacement energy storage followed by set-displacement fracturing, B-displacement energy storage followed by set-displacement fracturing...where A and B both belong to small displacements; the energy storage fracturing method of large-displacement direct fracturing may include: M-displacement direct fracturing, N-displacement direct fracturing...where M and N both belong to large displacements.

[0139] Furthermore, the selected energy storage fluid, the selected fracturing fluid and the selected energy storage fracturing fluid all include multiple types and can be liquids or gases, such as produced water, carbon dioxide, and the like.

[0140] Specifically, when using the selected energy storage fluid for small-displacement energy storage, the injection volume of the selected energy storage fluid needs to be reversed by the formation fracture pressure, and the injection pressure is controlled to be less than the formation fracture pressure to ensure that the selected energy storage fluid is injected without creating fractures and only storing energy.

[0141] The injection amount of the selected accumulator fluid is calculated by the following method:

[0142] 1. If the energy storage fluid is selected as liquid:

[0143] According to the material balance equation method:

[0144] N p B o +W p B w -W i B w =NC e B oi ΔP (3)

[0145] B o =B oi ·e co(Pi-P) (4)

[0146] B w =B wi ·e cw(Pi-P) (5)

[0147] For N in formula (3), p Find the derivative of P, let The solution is P, which is recorded as P 0 .

[0148] When P 0 Greater than or equal to the formation fracture pressure P f When the lower limit of the formation fracture pressure is taken as Pfdown is the reasonable formation pressure level P 1 When P 0 When it is less than the formation fracture pressure, P 0 is the reasonable formation pressure level P1. That is:

[0149]

[0150] The reasonable formation pressure level P is obtained 1 and the current actual formation pressure P 2 The formation pressure that needs to be increased by energy storage can be obtained by the following formula:

[0151] ΔP=P 1 -P 2 (7)

[0152] Substituting formula (7) into formula (3) yields:

[0153] W i =[N p B o +W p B w -NC e B oi (P 1 -P 2 )] / Bw (8)

[0154] Prediction of cumulative oil production using numerical simulation p and the cumulative water production W p After that, the required liquid volume W can be calculated by formula (8) i When using numerical simulation prediction, reservoir numerical simulation software can be used to establish a reservoir model. According to the historical data obtained from existing field instrument measurements, historical fitting (fitting oil production and water production) can be performed to verify the accuracy of the model, and then the oil production and water production in a certain number of years in the future can be predicted.

[0155] Among them, W i is the volume of liquid required, W p is the cumulative water production, N p is the cumulative oil production, N is the initial crude oil formation reserves before the test well energy storage fracturing, B o is the crude oil volume coefficient, B oi is the initial crude oil volume coefficient before energy storage fracturing in the test well, B w is the water volume coefficient, B wi is the initial water volume coefficient of the test well before energy storage fracturing, Co is the crude oil compressibility coefficient, Cw is the water compressibility coefficient, Ce is the combined compressibility coefficient of crude oil and water, Pi is the initial formation pressure before energy storage fracturing of the test well, P 1is the reasonable formation pressure level, P 2 is the current actual formation pressure, ΔP is the preset formation pressure amplitude, which is the formation pressure amplitude that you want to increase through energy storage.

[0156] 2. If the selected energy storage fluid is gas:

[0157] Regardless of whether the selected storage fluid is gas or liquid, assuming that the reasonable formation pressure level remains unchanged, the gas volume is calculated based on the known reasonable formation pressure level.

[0158] According to the material balance equation method, assuming that there is no gas cap in the formation after mining, and considering the elastic expansion volume of rock and bound water:

[0159] V 1 =N p B o +W p B w +[N p R p +(NN p )R s -NR si ] / B g- NC e B oi ΔP (9)

[0160] Prediction of cumulative oil production using numerical simulation p , the required gas volume V at a reasonable formation pressure level can be obtained 1 . Using numerical simulation to predict cumulative oil production N p The method is the same as above and will not be repeated here.

[0161] Among them, V 1 is the required gas volume at a reasonable formation pressure level, R p is the gas-oil ratio in the cumulative oil production, R s is the gas-oil ratio of the test well at the end of the soaking period, R si is the initial gas-oil ratio of the test well before energy storage fracturing, N p is the cumulative oil production, N is the initial crude oil formation reserves before the test well energy storage fracturing, B o is the crude oil volume coefficient, B w is the water volume coefficient, Ce is the combined compressibility coefficient of crude oil and water, B oi is the initial crude oil volume coefficient before energy storage fracturing in the test well, B g is the volume coefficient of natural gas.

[0162] According to the ideal gas state equation, the gas compression factor at a reasonable formation pressure level is derived:

[0163]

[0164] Among them, Z 1 is the gas compressibility factor at a reasonable formation pressure level, P 3 is the gas pressure at a reasonable formation pressure level, V 1 is the gas volume required at a reasonable formation pressure level, n 1 is the amount of gas at a reasonable formation pressure level, T 1 is the formation temperature, and R is the gas constant.

[0165] The calculation formula for converting the gas volume under the reasonable formation pressure level to the required gas volume under the current environmental conditions is:

[0166]

[0167] Among them, V 2 is the required gas volume under current environmental conditions, P 4 is the gas pressure under current environmental conditions, T 2 is the temperature under current environmental conditions, Z 2 is the compressibility factor of the gas under current environmental conditions.

[0168] In the examples herein, reference Figure 4 The step of determining the formation pressure evaluation factor of the well group according to the pressure values ​​of the test well, the monitoring well and the infill well in the well group, and the volume of the energy storage fracturing fluid when the test well is subjected to energy storage fracturing, further comprises:

[0169] S301: Obtaining a stable pressure value of the test well, a stable pressure value of the monitoring well, and a stable pressure value of the infill well according to the pressure values ​​of the test well, the monitoring well, and the infill well in the well group;

[0170] S302: Obtaining an average pressure value of the well group according to the stable pressure value of the test well, the stable pressure value of the monitoring well and the stable pressure value of the infill well;

[0171] S303: Obtaining a formation pressure increase amplitude according to a difference between the average pressure value of the well group and the initial pressure value of the formation of the well group;

[0172] S304: Obtaining an energy storage coefficient according to the formation pressure increase amplitude and the volume of energy storage fracturing fluid when performing energy storage fracturing on the test well;

[0173] S305: Determine the formation pressure increase amplitude and the energy storage coefficient as the formation pressure evaluation factor of the well group.

[0174] During the process of energy storage fracturing and well soaking of the test well, the pressure values ​​of the test well, monitoring well and infill well all rise first and then fall until they stabilize to a stable value. The average pressure value of the well group is obtained by taking the average value of all the test wells, monitoring wells and infill wells in the well group. The initial formation pressure value of the well group is the formation pressure before energy storage fracturing of the test well. The difference between the average pressure value of the well group and the initial formation pressure value of the well group can be used to obtain the increase in formation pressure.

[0175] Furthermore, the energy storage coefficient can be calculated by the following formula:

[0176]

[0177] Among them, E V is the energy storage coefficient, V R is the volume of the selected energy storage fluid. If the energy storage fracturing method of small-displacement energy storage followed by set-displacement fracturing is adopted, V R V is the sum of the volume of the selected energy storage fluid during the energy storage process and the volume of the selected fracturing fluid during fracturing. If the energy storage fracturing method of large-volume direct fracturing is adopted, V R The volume of energy storage fracturing fluid selected in large-volume fracturing, P n is the increase in formation pressure.

[0178] The formation pressure increase amplitude and the energy storage coefficient are determined as the formation pressure evaluation factor of the well group. The closer the energy storage coefficient is to the standard energy storage coefficient, the better the energy storage fracturing effect of the well group is. The standard energy storage coefficient is determined according to the actual working conditions. The larger the formation pressure increase amplitude is, the better the energy storage fracturing effect of the well group is. Therefore, the energy storage fracturing effect of the well group is evaluated by the formation pressure evaluation factor of the well group.

[0179] In the examples herein, reference Figure 5 The determining of the fracture state evaluation factor of the well group according to the first time when the infill well generates a pressure response for the first time, the position of the infill well, and the pumping speed of the energy storage fracturing fluid when the test well is subjected to energy storage fracturing; the second time when the infill well generates a pressure response for the first time, the position of the infill well, and the pumping speed of the fracturing fluid when the monitoring well is subjected to fracturing further includes:

[0180] S401: Calculate a first response amount of the first pressure response generated by the infill well according to the first time when the infill well generates a pressure response for the first time and the pumping speed of the energy storage fracturing fluid when performing energy storage fracturing on the test well;

[0181] S402: Obtaining a fracture diffusion coefficient of a corresponding test well according to the first time when the infill well first generates a pressure response and the position of the infill well;

[0182] S403: Calculate a second response amount of the first pressure response generated by the infill well according to the second time when the infill well first generates a pressure response and the pumping speed of the fracturing fluid when fracturing the monitoring well;

[0183] S404: Obtaining a fracture diffusion coefficient of a corresponding monitoring well according to the second time when the infill well first generates a pressure response and the position of the infill well;

[0184] S405: Determine the first response amount of the first pressure response generated by the infill well and the fracture diffusion coefficient of the corresponding test well, the second response amount of the first pressure response generated by the infill well and the fracture diffusion coefficient of the corresponding monitoring well as the fracture state evaluation factors of the well group.

[0185] In S401 and S403, specifically, the first response amount or the second response amount of the first pressure response generated by the infill well is calculated by the following formula:

[0186] Q=qt (13)

[0187] Among them, Q is the first response amount or the second response amount of the first pressure response generated by the infill well, q is the pumping speed of the energy storage fracturing fluid when the test well is subjected to energy storage fracturing or the pumping speed of the fracturing fluid when the monitoring well is subjected to fracturing, and t is the first time or the second time when the infill well first generates a pressure response.

[0188] In S402 and S404, specifically, the crack diffusion coefficient is calculated by the following formula:

[0189]

[0190] Among them, D k is the fracture diffusion coefficient of the test well or monitoring well, L is the distance between the location of the infill well and the location of the corresponding test well or monitoring well, and t is the first time or the second time when the infill well first generates a pressure response.

[0191] In S405, for the test well, the smaller the fracture diffusion coefficient, the larger the first response, which means that new fractures may be generated and the fractures are more complex, and the energy storage fracturing effect of the well group is better. The larger the fracture diffusion coefficient, the smaller the first response, which means that new fractures may not be generated and the fractures are relatively simple, and the energy storage fracturing effect of the well group is worse. The same is true for the monitoring wells. Therefore, the energy storage fracturing effect of the well group can be evaluated by the fracture state evaluation factor of the well group.

[0192] In the examples herein, reference Figure 6The step of determining the oil production evaluation factor of the well group according to the pressure values ​​of the test wells, monitoring wells and infill wells in the well group, and the oil production of the test wells and monitoring wells after fracturing, further comprises:

[0193] S501: according to the pressure values ​​of the test well, the monitoring well and the infill well in the well group, obtain the stable pressure value of the test well, the stable pressure value of the monitoring well and the stable pressure value of the infill well;

[0194] S502: Obtaining an average pressure value of the well group according to the stable pressure value of the test well, the stable pressure value of the monitoring well and the stable pressure value of the infill well;

[0195] S503: Obtaining a formation pressure increase amplitude according to a difference between the average pressure value of the well group and the initial pressure value of the formation of the well group;

[0196] S504: Obtaining a production increase coefficient according to the formation pressure increase amplitude and the oil production of the test well and the monitoring well after fracturing;

[0197] S505: Determine the production increase coefficient as the oil production evaluation factor of the well group.

[0198] According to the above, when determining the formation pressure evaluation factor of the well group, the formation pressure increase amplitude can be obtained. This article will not repeat it here. Further, the production increase coefficient can be calculated by the following formula:

[0199]

[0200] Among them, Ez is the production increase coefficient, M is the oil production after fracturing of the test well and monitoring well, P n is the increase in formation pressure.

[0201] The test wells and monitoring wells are opened for oil production to obtain the daily oil production of the test wells and monitoring wells. The daily oil production for 365 days is accumulated to obtain the annual oil production of the test wells and monitoring wells. Of course, the quarterly oil production and monthly oil production of the test wells and monitoring wells can also be calculated, which will not be described in detail in this article. The daily oil production, annual oil production or quarterly oil production of the test wells and monitoring wells can be used as the oil production of the test wells and monitoring wells after fracturing, and the production increase coefficient can be calculated. The larger the production increase coefficient, the better the energy storage fracturing effect of the well group, and the oil production evaluation factor of the well group is used to evaluate the energy storage fracturing effect of the well group.

[0202] In summary, the energy storage fracturing effect of the well group can be comprehensively evaluated through the formation pressure evaluation factor, fracture state evaluation factor, and oil production evaluation factor of the well group, and the energy storage fracturing effect of the well group after the test well is subjected to energy storage fracturing by the selected energy storage fracturing method can be obtained.

[0203] Of course, the method described in this article can be used to select two groups of wells with the same environmental conditions for a control test. Test wells with the same pressure conditions are selected from the two groups of wells for energy storage fracturing. The test wells of the first group of wells are subjected to energy storage fracturing using type A energy storage fracturing method, and the test wells of the second group of wells are subjected to energy storage fracturing using type B energy storage fracturing method. The energy storage fracturing effects of the first and second groups of wells are compared to determine the more suitable energy storage fracturing method for the well group under the current environmental conditions.

[0204] The method described in this article can also be used to evaluate the energy storage fracturing effect of the test well itself under the selected energy storage fracturing method after the test well is subjected to energy storage fracturing and well shut-in using the selected energy storage fracturing method, through the first response amount of the first pressure response generated by the infill well, the corresponding fracture diffusion coefficient of the test well, and the daily oil production and annual oil production of the test well.

[0205] The method described in this article can also be used to evaluate the impact of the test well's energy storage fracturing effect on the monitoring well under the selected energy storage fracturing method after the test well is subjected to energy storage fracturing and well shut-in by measuring the second response of the first pressure response generated by the infill well, the corresponding fracture diffusion coefficient of the monitoring well, and the daily oil production and annual oil production of the monitoring well.

[0206] In addition, refer to Figure 7 The method in this paper is also applicable to the evaluation of the influence of the test wells on the energy storage fracturing effect of other monitoring wells outside the well group under the selected energy storage fracturing mode by performing energy storage fracturing and well soaking on the test wells in the well group. This influence is mainly reflected by the fracture state, as follows:

[0207] S601: selecting another monitoring well from outside the well group, where the distance between the other monitoring well and the test well is less than a set distance;

[0208] S602: Opening other infill wells between the other monitoring wells and the adjacent production wells;

[0209] S603: Fracturing and soaking the other monitoring wells;

[0210] S604: During the process of fracturing and soaking the other monitoring wells, record the time when the other infill wells first generate pressure response;

[0211] S605: Determine the fracture state of the other monitoring wells under the influence of the test well according to the time when the other infill wells generate a pressure response for the first time, the location of the other infill wells, and the pumping speed of the fracturing fluid when fracturing the other monitoring wells.

[0212] Because other monitoring wells are selected outside the well group, and other monitoring wells should not be too far away from the test well, the distance between the two is less than the set distance. In order to determine the fracture status of other monitoring wells, other infill wells need to be opened between other monitoring wells and the adjacent production wells. Other monitoring wells are the same as the monitoring wells in the well group, and pressure sensors need to be installed. Other infill wells are the same as the infill wells in the well group, and wellbore pressure monitoring devices need to be installed.

[0213] After the energy storage fracturing and soaking of the test well are completed (i.e., after S101 and S103 are executed), the above S603 to S605 are executed. In S605, the response amount and the fracture diffusion coefficient can be calculated by the time when other infill wells generate the first pressure response and the position of the other infill wells. Specifically, they can be calculated using formulas (13) and (14).

[0214] Then, the fracture status of other monitoring wells under the influence of the test well is determined by the response amount and the fracture diffusion coefficient: the smaller the fracture diffusion coefficient, the larger the response amount, which means that new fractures may be generated and the fractures are more complex, and the fracture status of other monitoring wells is better; while the larger the fracture diffusion coefficient, the smaller the response amount, which means that new fractures may not be generated and the fractures are relatively simple, and the fracture status of other monitoring wells is worse.

[0215] In this article, other monitoring wells refer to a well selected outside the well group. For other monitoring wells, through the above S601 to S605, the fracture state of other monitoring wells under the influence of the test well can be obtained. For other monitoring wells, the evaluation method described in S101 to S109 is different, because S101 to S109 evaluate the well group as a whole, while other monitoring wells only evaluate a well outside the well group. For the well group as a whole, it is necessary to obtain the energy storage fracturing effect of the well group based on the formation pressure evaluation factor, fracture state evaluation factor, and oil production evaluation factor of the well group; but since the increase in formation pressure cannot be measured by the pressure value of a well, there is no need to conduct formation pressure evaluation for other monitoring wells, nor is there any need to conduct oil production evaluation according to the oil production evaluation method of the well group in this article.

[0216] Of course, other monitoring wells can also be evaluated for pressure, and the bottom hole pressure of other monitoring wells before fracturing and the bottom hole pressure of the test well can be obtained after the energy storage fracturing of the test well. If the bottom hole pressure of other monitoring wells increases after the energy storage fracturing of the test well, and the increase exceeds the threshold, the energy storage fracturing of the test well is effective for other monitoring wells. Otherwise, the energy storage fracturing of the test well has no effect on other monitoring wells. Other monitoring wells can also be evaluated for oil production, and the daily oil production of other monitoring wells before fracturing can be obtained, and the daily oil production after fracturing can be obtained. If the daily oil production after fracturing is greater than the daily oil production of other monitoring wells without energy storage fracturing, the energy storage fracturing of the test well is effective for other monitoring wells. Otherwise, the energy storage fracturing of the test well has no effect on other monitoring wells. In this way, the bottom hole pressure, fracture state and oil production of other monitoring wells under the influence of the test well can be further integrated to obtain the energy storage fracturing effect of other monitoring wells outside the well group.

[0217] Based on the above-mentioned method for evaluating the effect of energy storage fracturing, the embodiments of this article also provide an evaluation device for the effect of energy storage fracturing. The device may include a system (including a distributed system), software (application), module, component, server, client, etc. using the method described in the embodiments of this article and a device combined with necessary implementation hardware. Based on the same innovative concept, the device in one or more embodiments provided in the embodiments of this article is as described in the following embodiments. Since the implementation scheme and method of the device to solve the problem are similar, the implementation of the specific device in the embodiments of this article can refer to the implementation of the aforementioned method, and the repetitions will not be repeated. As used below, the term "unit" or "module" can be a combination of software and / or hardware that implements a predetermined function. Although the device described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceived.

[0218] Specifically, Figure 8 This is a schematic diagram of the module structure of an embodiment of an energy storage fracturing effect evaluation device provided in the embodiments of this article, referring to Figure 8 As shown, an evaluation device for energy storage fracturing effect provided in an embodiment of the present invention includes: a selection module 100, an energy storage fracturing module 200, a first recording module 300, a first determination module 400, a fracturing module 500, a second recording module 600, a second determination module 700, a third determination module 800, and an effect determination module 900.

[0219] The selection module 100 is used to select a well whose internal pressure is lower than a set pressure in the well group as a test well, and select other wells in the well group except the test well as monitoring wells; an infill well is opened between two adjacent wells in the well group;

[0220] The energy storage fracturing module 200 is used to perform energy storage fracturing and well soaking on the test well according to the selected energy storage fracturing method;

[0221] The first recording module 300 is used to record the pressure values ​​of the test well, the monitoring well and the infill well in the well group in real time during the process of energy storage fracturing and well soaking of the test well, and record the first time when the infill well first generates a pressure response;

[0222] A first determination module 400 is used to determine a formation pressure evaluation factor of the well group according to the pressure values ​​of the test well, the monitoring well and the infill well in the well group, and the volume of the energy storage fracturing fluid when the test well is subjected to energy storage fracturing;

[0223] A fracturing module 500, used for fracturing and soaking the monitoring well;

[0224] The second recording module 600 is used to record the second time when the infill well first generates a pressure response during the fracturing and soaking process of the monitoring well;

[0225] The second determination module 700 is used to determine the fracture state evaluation factor of the well group according to the first time when the infill well first generates a pressure response, the position of the infill well, and the pumping speed of the energy storage fracturing fluid when the test well is subjected to energy storage fracturing; the second time when the infill well first generates a pressure response, the position of the infill well, and the pumping speed of the fracturing fluid when the monitoring well is subjected to fracturing;

[0226] The third determination module 800 is used to determine the oil production evaluation factor of the well group according to the pressure values ​​of the test wells, monitoring wells and infill wells in the well group, and the oil production after fracturing of the test wells and monitoring wells;

[0227] The effect determination module 900 is used to obtain the energy storage fracturing effect of the well group according to the formation pressure evaluation factor, the fracture state evaluation factor, and the oil production evaluation factor of the well group.

[0228] Reference Fig. 9As shown, based on the above-mentioned method for evaluating the effect of energy storage fracturing, a computer device 902 is also provided in one embodiment of this invention, wherein the above-mentioned method is run on the computer device 902. The computer device 902 may include one or more processors 904, such as one or more central processing units (CPUs) or graphics processing units (GPUs), and each processing unit may implement one or more hardware threads. The computer device 902 may also include any memory 906, which is used to store any kind of information such as code, settings, data, etc. In a specific embodiment, the computer program on the memory 906 and which can be run on the processor 904, when the computer program is run by the processor 904, can execute instructions according to the above-mentioned method. Non-limitingly, for example, the memory 906 may include any one or more combinations of the following: any type of RAM, any type of ROM, flash memory device, hard disk, optical disk, etc. More generally, any memory may use any technology to store information. Further, any memory may provide volatile or non-volatile retention of information. Further, any memory may represent a fixed or removable component of the computer device 902. In one embodiment, when the processor 904 executes the associated instructions stored in any memory or combination of memories, the computer device 902 can perform any operation of the associated instructions. The computer device 902 also includes one or more drive mechanisms 908 for interacting with any memory, such as a hard disk drive mechanism, an optical disk drive mechanism, etc.

[0229] The computer device 902 may also include an input / output module 910 (I / O) for receiving various inputs (via input devices 912) and for providing various outputs (via output devices 914). A specific output mechanism may include a presentation device 916 and an associated graphical user interface 918 (GUI). In other embodiments, the input / output module 910 (I / O), input device 912, and output device 914 may not be included, and the computer device 902 may be used as a computer device in a network. The computer device 902 may also include one or more network interfaces 920 for exchanging data with other devices via one or more communication links 922. One or more communication buses 924 couple the components described above together.

[0230] The communication link 922 may be implemented in any manner, for example, through a local area network, a wide area network (e.g., the Internet), a point-to-point connection, etc., or any combination thereof. The communication link 922 may include any combination of hardwired links, wireless links, routers, gateway functions, name servers, etc. governed by any protocol or combination of protocols.

[0231] Corresponds to Figure 1 , Figure 3-Figure 7The method in this article also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above method are executed.

[0232] The embodiment of the present invention also provides a computer readable instruction, wherein when the processor executes the instruction, the program therein causes the processor to execute the following Figure 1 , Figures 3 to 7 The method shown.

[0233] It should be understood that in the various embodiments of this document, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this document.

[0234] It should also be understood that in the embodiments of this article, the term "and / or" is only a description of the association relationship of the associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0235] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this article.

[0236] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0237] In the several embodiments provided herein, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of the units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, or can be electrical, mechanical or other forms of connection.

[0238] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments of this article.

[0239] In addition, each functional unit in each embodiment of this invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit may be implemented in the form of hardware or in the form of software functional unit.

[0240] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this article is essentially or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of this article. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0241] Specific embodiments are used in this article to illustrate the principles and implementation methods of this article. The description of the above embodiments is only used to help understand the methods and core ideas of this article. At the same time, for general technicians in this field, according to the ideas of this article, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on this article.

Claims

1. A method for evaluating the effect of energy storage fracturing, characterized in that: include: Select test wells, monitoring wells and infill wells from the well group; Carry out energy storage fracturing and well soaking on the test well, record the pressure values ​​of the test well, monitoring well and infill well in real time, and record the time when the infill well first produces pressure response as the first time; According to the pressure values ​​of the test well, monitoring well and infill well, as well as the initial formation pressure value of the well group, the formation pressure increase amplitude is obtained, and the energy storage coefficient is obtained by combining the volume of energy storage fracturing fluid during energy storage fracturing of the test well; The formation pressure increase amplitude and energy storage coefficient are determined as the formation pressure evaluation factors of the well group; Perform fracturing and well soaking on the monitoring well, and record the time when the infill well first produces pressure response as the second time; According to the first time and the pumping speed of the energy storage fracturing fluid during energy storage fracturing of the test well, the pressure response generated by the infill well for the first time is calculated as the first response amount; According to the first time and the position of the infill well, the fracture diffusion coefficient of the corresponding test well is obtained; According to the second time and the pumping speed of the fracturing fluid when the monitoring well is fracturing, the pressure response generated by the infill well for the first time is calculated as the second response amount; According to the second time and the position of the infill well, a fracture diffusion coefficient of the corresponding monitoring well is obtained; The first response amount and the fracture diffusion coefficient of the corresponding test well, and the second response amount and the fracture diffusion coefficient of the corresponding monitoring well are determined as fracture state evaluation factors of the well group; According to the pressure values ​​of the test well, monitoring well and infill well, as well as the initial formation pressure value of the well group, the formation pressure increase amplitude is obtained, and the production increase coefficient is obtained by combining the oil production after fracturing of the test well and monitoring well, which is determined as the oil production evaluation factor of the well group; The closer the energy storage coefficient is to the standard energy storage coefficient, the smaller the fracture diffusion coefficient of the test well, the smaller the fracture diffusion coefficient of the monitoring well, the larger the production increase coefficient, and the better the energy storage fracturing effect of the well group.

2. The method for evaluating the effect of energy storage fracturing according to claim 1, characterized in that: There are one or more test wells, and the pressure inside the test wells is lower than the pressure inside the monitoring wells; If there are multiple test wells, performing energy storage fracturing and well soaking on the test wells according to the selected energy storage fracturing method further includes: Arrange the plurality of test wells in order from small to large according to the pressure inside the wells; The test well is subjected to energy storage fracturing and well soaking in the sorted order according to the selected energy storage fracturing method.

3. The method for evaluating the effect of energy storage fracturing according to claim 2, characterized in that: The selected energy storage fracturing method includes: An energy storage fracturing method in which a selected energy storage fluid is used to store energy in a small displacement, and then a selected fracturing fluid is used to perform fracturing in a set displacement, and an energy storage fracturing method in which a selected energy storage fracturing fluid is used to perform direct fracturing in a large displacement; wherein the small displacement is smaller than the set displacement, and the large displacement is larger than the set displacement.

4. The method for evaluating the effect of energy storage fracturing according to claim 1, characterized in that: The first response amount or the second response amount is calculated by the following formula: ； Among them, Q is the first response amount or the second response amount, q is the pumping speed of the energy storage fracturing fluid when the test well is subjected to energy storage fracturing or the pumping speed of the fracturing fluid when the monitoring well is subjected to fracturing, and t is the first time or the second time.

5. The method for evaluating the effect of energy storage fracturing according to claim 1, characterized in that: The crack diffusion coefficient is calculated by the following formula: ； Among them, D k is the fracture diffusion coefficient of the test well or monitoring well, L is the distance between the location of the infill well and the location of the corresponding test well or monitoring well, and t is the first time or the second time.

6. The method for evaluating the effect of energy storage fracturing according to claim 1, characterized in that: Also includes: Selecting another monitoring well from outside the well group, wherein the distance between the other monitoring well and the test well is less than the set distance; Opening other infill wells between the other monitoring wells and the adjacent oil production wells; Performing fracturing and soaking on the other monitoring wells; During the fracturing and soaking process of the other monitoring wells, recording the time when the other infill wells first generate pressure response; The fracture state of the other monitoring wells under the influence of the test well is determined according to the time when the other infill wells first generate pressure response, the location of the other infill wells, and the pumping speed of the fracturing fluid when fracturing the other monitoring wells.

7. An evaluation device for energy storage fracturing effect, characterized in that: include: Select the module, and select the test well, monitoring well and infill well in the well group; Carry out energy storage fracturing and well soaking on the test well; The recording module records the pressure values ​​of the test well, monitoring well and infill well in real time. The time when the infill well first generates pressure response is the first time; The first determination module obtains the formation pressure increase amplitude according to the pressure values ​​of the test well, the monitoring well and the infill well and the initial formation pressure value of the well group, and obtains the energy storage coefficient in combination with the volume of the energy storage fracturing fluid during the energy storage fracturing of the test well; the formation pressure increase amplitude and the energy storage coefficient are determined as the formation pressure evaluation factor of the well group; The fracturing module performs fracturing and well shut-in of the monitoring well, and records the time when the infill well first generates pressure response as the second time; The second determination module calculates the first pressure response generated by the infill well as a first response amount according to the first time and the pumping speed of the energy storage fracturing fluid during the energy storage fracturing of the test well; and obtains the fracture diffusion coefficient of the test well according to the first time and the position of the infill well; According to the second time and the pumping speed of the fracturing fluid during the fracturing of the monitoring well, the pressure response generated by the infill well for the first time is calculated as the second response amount; according to the second time and the position of the infill well, the fracture diffusion coefficient of the monitoring well is obtained; The first response quantity and the fracture diffusion coefficient of the test well, the second response quantity and the fracture diffusion coefficient of the monitoring well are determined as the fracture state evaluation factors of the well group; According to the pressure values ​​of the test well, monitoring well and infill well and the initial formation pressure value of the well group, the formation pressure increase amplitude is obtained. Combined with the oil production after fracturing of the test well and monitoring well, the production increase coefficient is obtained and determined as the oil production evaluation factor of the well group; In the effect determination module, the closer the energy storage coefficient is to the standard energy storage coefficient, the smaller the fracture diffusion coefficient of the test well is, the smaller the fracture diffusion coefficient of the monitoring well is, the larger the production increase coefficient is, and the better the energy storage fracturing effect of the well group is.

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