Dense rock breakthrough pressure measurement system, method and apparatus, and computer device

Abstract

A dense rock breakthrough pressure measurement system, method and apparatus, and a computer device, relating to the field of oil and gas field exploration and development. The system comprises: a rock sample (100), a gas injector (101), a gas receiver (102), a gas component detector (108), at least one acoustic sensor, and a control assembly (104); the gas injector (101) is connected to one end of the rock sample (100) in the width direction and is configured to inject gas into the rock sample (100) at an initial gas injection pressure and a preset temperature; the gas receiver (102) is configured to collect gas discharged from the tail end of the rock sample (100); the gas component detector (108) is configured to measure the component and content of the injection gas outputted from the tail end of the rock sample (100); and the control assembly (104) is configured to determine an average breakthrough pressure of the rock sample (100) on the basis of acoustic signals passing through the rock sample (100) and collected by acoustic receivers (1032), and on the basis of the breakthrough pressures of the positions of the different acoustic receivers (1032) and the overall breakthrough pressure.

Description

Dense rock breakthrough pressure measurement system, method, device and computer equipment

[0001] Related applications

[0002] This application claims priority to Chinese patent application No. 202311228149.0 filed on September 21, 2023, and cites the contents disclosed in the above patent application as part of this application. Technical Field

[0003] The present application relates to the field of oil and gas field exploration and development, and in particular to a system, method, device and computer equipment for measuring breakthrough pressure of dense rock. Background Art

[0004] Breakthrough pressure is the minimum pressure required for a non-wetting fluid to overcome the capillary pressure of a wetting fluid in a porous medium, forming a continuous mobile phase. Breakthrough pressure can be used to calculate the sealing capacity of a caprock or barrier layer. It is one of the most direct and important parameters for evaluating caprocks in conventional oil and gas reservoirs, a key parameter for developing heating strategies for in-situ development of unconventional shale oil, and a crucial indicator for evaluating the blocking conditions of underground gas storage reservoirs. During in-situ shale oil development, it is necessary to evaluate the breakthrough pressure of the sealing layer of the heated geological body under different temperature conditions, thereby formulating a reasonable heating program based on this pressure.

[0005] Existing methods for measuring breakthrough pressure include mercury intrusion, displacement, centrifugation, porous plate, and gas desorption, with mercury intrusion and displacement being the most commonly used. The mercury intrusion method records the amount of mercury injected at different pressure points to generate a capillary force curve plotting mercury saturation versus pressure, from which the pore radius and breakthrough pressure are calculated. However, this method has drawbacks: mercury vapor forms when heated, polluting the environment. Furthermore, its assumed wetting contact angle deviates significantly from the actual value, significantly impacting the accuracy of the test results. The gas displacement method, adopted by the industry standard (SY / T 5748-2020), uses a flowmeter to monitor the sample outlet. It assumes that when bubbles escape uniformly and continuously, the pressure difference between the inlet and outlet of the sample is the gas breakthrough pressure of the sample. A drawback of this method is that the liquid saturated in the sample boils and evaporates at high temperatures, forming bubbles, which affects the accuracy of the test results.

[0006] When testing the breakthrough pressure of rock samples, the method used to observe or detect the motion of the non-wetting phase significantly impacts the test time and accuracy of the results. Common methods include visual observation, weighing, nuclear magnetic resonance (NMR), resistivity, CT, and induction logging. The drawbacks of these observation methods are that they are time-consuming and have low accuracy. This limitation is exacerbated in dense rock, where the non-wetting phase's breakthrough within the sample is very slow.

[0007] It can be seen that for the detection of breakthrough pressure of dense rocks, the existing mainstream methods and the corresponding non-wetting phase observation methods have significant defects. They can neither produce high-precision detection results nor perform detection under high temperature conditions. They cannot well meet the needs of oil and gas exploration and development and underground gas storage construction.

[0008] Summary of the Invention

[0009] In order to solve the problem that the detection results of the above-mentioned prior art are not accurate and cannot be detected under high temperature conditions, the embodiments of the present application provide a dense rock breakthrough pressure measurement system, method, device and computer equipment.

[0010] The embodiment of the present application provides a dense rock breakthrough pressure measurement system, the system includes: a rock sample, a gas injector, a gas receiver, a gas composition detector, at least one group of acoustic sensors and a control component; the gas injector is connected to one end of the rock sample in the width direction, and is used to inject gas into the rock sample at an initial gas injection pressure and a preset temperature; the gas receiver is connected to the other end of the rock sample in the width direction, and is used to collect gas discharged from the end of the rock sample, and the gas injector and the gas receiver are symmetrically arranged along the long axis of the rock sample; the gas composition detector is used to detect the composition and content of the injected gas output from the end of the rock sample; at least one group of acoustic sensors includes: an acoustic generator and an acoustic receiver, and the line formed by the acoustic generator and the acoustic receiver in each group of acoustic sensors intersects with the line formed by the gas injector and the gas receiver, wherein the acoustic generator is used to emit gas into the rock sample. The acoustic receiver is used to collect the acoustic signals after propagation in the rock sample; the control component is used to determine the average speed of the acoustic signal passing through the rock sample and the breakthrough position of the injected gas in the rock sample based on the acoustic signal passing through the rock sample collected by the acoustic receiver; determine whether to increase the gas injection pressure according to the breakthrough position; if so, increase the gas injection pressure and calculate the average speed of the sound wave passing through the rock sample, and repeatedly determine the breakthrough position of the injected gas in the rock sample until the injected gas breaks through and reaches the end of the rock sample; determine the breakthrough pressure of different acoustic receiver positions of the dense rock sample according to the gas injection pressure corresponding to each acoustic receiver position; determine the overall breakthrough pressure of the rock sample according to the changes in the composition and content of the injected gas recorded by the gas composition detector; determine the average breakthrough pressure of the rock sample according to the breakthrough pressures at different acoustic receiver positions and the overall breakthrough pressure.

[0011] According to one aspect of an embodiment of the present application, the system also includes: a rock sample holder for fixing the rock sample; a rock sample sealing sleeve for sealing the space between the rock sample and the rock sample holder; and a heating assembly for heating the rock sample to a preset temperature and controlling the heating rate of the rock sample.

[0012] According to one aspect of the embodiment of the present application, the rock sample sealing sleeve is made of a high temperature and high pressure resistant material.

[0013] An embodiment of the present application provides a method for measuring the breakthrough pressure of tight rock, including: injecting gas into a rock sample through a gas injector under the action of an initial gas injection pressure and a preset temperature; determining the average velocity of sound waves passing through the rock sample and the breakthrough position of the injected gas in the rock sample according to the sound signals passing through the rock sample collected by each acoustic receiver; determining whether to increase the gas injection pressure according to the average velocity and the breakthrough position; if so, increasing the gas injection pressure and calculating the average velocity of sound waves passing through the rock sample, and repeating to determine the breakthrough position of the injected gas in the rock sample until the injected gas breaks through to reach the end of the rock sample; determining the breakthrough pressure at different acoustic receiver positions of the rock sample according to the gas injection pressure corresponding to each acoustic receiver position; determining the overall breakthrough pressure of the rock sample according to the change results of the composition and content of the injected gas output from the end of the rock sample recorded by the gas composition detector; and determining the average breakthrough pressure of the rock sample according to the breakthrough pressure at different acoustic wave receiver positions and the overall breakthrough pressure.

[0014] According to an aspect of an embodiment of the present application, determining the average velocity of sound waves passing through the rock sample and the breakthrough position of the injected gas in the rock sample includes: determining the number n of the average velocities of sound waves passing through the rock sample recorded by each acoustic receiver within a preset period that are less than a preset velocity; if n = 0, determining that the injected gas has not broken through to reach the acoustic receiver closest to the gas injector; if n = 1, determining the position of the first acoustic receiver as the breakthrough position of the injected gas in the rock sample; if n > 1 and n < N, where N represents the total number of acoustic receivers, taking the position of the acoustic receiver closest to the gas receiver among the acoustic receivers recording the average velocity of sound waves passing through the rock sample less than the preset velocity as the breakthrough position of the injected gas in the rock sample; if n = N, determining the breakthrough position of the injected gas in the rock sample according to the composition and content of the injected gas output from the end of the rock sample detected by the gas composition detector.

[0015] According to an aspect of an embodiment of the present application, determining the breakthrough position of the injected gas in the rock sample according to the composition and content of the injected gas output from the end of the rock sample detected by the gas composition detector includes: judging whether the increase amplitude of the content of the injected gas output from the end of the rock sample exceeds a preset threshold; if not exceeding the preset threshold, determining the position of the last acoustic receiver as the breakthrough position of the injected gas in the rock sample; if exceeding the preset threshold, judging whether the gas injection pressure when the increase amplitude of the output injected gas content exceeds the preset threshold is the initial gas injection pressure; if the gas injection pressure is the initial gas injection pressure, terminating the experiment; if the gas injection pressure is the increased pressure, determining that the injected gas breaks through to reach the end in the rock sample.

[0016] According to one aspect of an embodiment of the present application, the breakthrough pressure of different acoustic receiver positions of the dense rock sample is determined based on the gas injection pressure recorded at each acoustic receiver position: when the injected gas breaks through and reaches each acoustic receiver position, the gas injection pressure is recorded; the gas injection pressure at which the injected gas breaks through and reaches each acoustic receiver position is recorded as the breakthrough pressure at that position.

[0017] According to one aspect of an embodiment of the present application, determining whether to increase the gas injection pressure based on the average speed and breakthrough position includes: when the average speed of the sound waves passing through the rock sample recorded by all acoustic receivers is not lower than the preset speed, increasing the gas injection pressure; when the average speed of the sound waves passing through the rock sample recorded by some acoustic receivers is lower than the preset speed, and the breakthrough position of the injected gas in the rock sample does not change within a preset period, increasing the gas injection pressure; when the average speed of the sound waves passing through the rock sample recorded by all acoustic receivers is lower than the preset speed, if the gas injection pressure is the initial gas injection pressure, terminating the test; if the gas injection pressure is the increased pressure, there is no need to adjust the gas injection pressure.

[0018] According to one aspect of an embodiment of the present application, the overall breakthrough pressure of the rock sample is determined by using the change results of the composition and content of the injected gas output from the end of the rock sample recorded by the gas composition detector, including: when the increase in the composition and content of the injected gas discharged from the end of the rock sample exceeds a preset threshold, and the gas injection pressure at this time is higher than the initial gas injection pressure, it is determined that the injected gas has broken through to reach the end of the sample, and the gas injection pressure at this time is recorded as the overall breakthrough pressure of the rock sample; when the increase in the composition and content of the injected gas discharged from the end of the rock sample is lower than the preset threshold, continue to detect and record the changes in the gas composition and gas content output from the end of the rock sample.

[0019] According to one aspect of an embodiment of the present application, the average breakthrough pressure of the rock sample is determined using the determined breakthrough pressures at different acoustic receiver positions of the rock sample and the overall breakthrough pressure. The average breakthrough pressure is determined using the following formula:

[0020] Among them, P ave represents the average breakthrough pressure, n represents the number of times the average speed of the sound wave passing through the rock sample recorded by each acoustic receiver within the preset period is less than the preset speed, P1 is the breakthrough pressure of the rock sample section at the connection position of the first group of sound transmitters and sound receivers, P2 is the breakthrough pressure of the rock sample section at the connection position of the second group of sound transmitters and sound receivers, P n is the breakthrough pressure of the rock sample section at the connection line between the nth group of sound transmitters and sound receivers, P e The breakthrough pressure of the entire rock sample is measured at the end of the rock sample.

[0021] The present application also provides a device for measuring breakthrough pressure of dense rock, comprising: a gas injection unit for injecting gas into a rock sample through a gas injector under the action of an initial gas injection pressure and a preset temperature; a breakthrough position determination unit for determining, based on acoustic signals passing through the rock sample collected by each acoustic receiver, an average velocity of the acoustic wave through the rock sample and a breakthrough position of the injected gas within the rock sample; a gas injection pressure increase determination unit for determining, based on the average velocity and breakthrough position, whether to increase the gas injection pressure; if so, increasing the gas injection pressure and calculating the average velocity of the acoustic wave through the rock sample, and repeatedly determining the breakthrough position of the injected gas within the rock sample until the injected gas reaches the end of the rock sample; a breakthrough pressure determination unit for determining, based on the gas injection pressure corresponding to each acoustic receiver position, the breakthrough pressure at different acoustic receiver positions of the rock sample; an overall breakthrough pressure determination unit for determining the overall breakthrough pressure of the rock sample based on changes in the composition and content of the injected gas output from the end of the rock sample recorded by a gas composition detector; and an average breakthrough pressure determination unit for determining the average breakthrough pressure of the rock sample based on the breakthrough pressures at different acoustic receiver positions and the overall breakthrough pressure.

[0022] An embodiment of the present application provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, a method for measuring breakthrough pressure of dense rock is implemented.

[0023] An embodiment of the present application also provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, a method for measuring the breakthrough pressure of dense rock is implemented.

[0024] Based on the characteristics of sound waves that propagate quickly and with large differences in speed in solids, liquids and gases, this application uses the change in the average speed of sound waves passing through rock samples to detect changes in the content of non-wetting phases in rock samples, thereby achieving high-precision and rapid detection of the breakthrough pressure of dense rocks, overcoming the defects of the existing technology and overcoming the shortcomings of the existing technology of single detection results and low accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0026] FIG1 is a schematic diagram of a dense rock breakthrough pressure measurement system according to an embodiment of the present application;

[0027] FIG2 is a flow chart of a method for measuring breakthrough pressure of dense rock according to an embodiment of the present application;

[0028] FIG3 is a flow chart of a method for determining a breakthrough arrival position of injected gas in a rock sample according to an embodiment of the present application;

[0029] FIG4 is a flow chart of another method for determining a breakthrough arrival position according to an embodiment of the present application;

[0030] FIG5 is a flow chart of a method for determining the increased gas injection pressure according to an embodiment of the present application;

[0031] FIG6 is a flow chart showing a method for determining the breakthrough pressure of a dense rock sample at different acoustic receiver positions according to an embodiment of the present application;

[0032] FIG7 is a flow chart of a method for determining the overall breakthrough pressure of a dense rock sample according to an embodiment of the present application;

[0033] FIG8 is a schematic structural diagram of a dense rock breakthrough pressure measurement device according to an embodiment of the present application;

[0034] FIG9 is a schematic diagram showing the specific structure of a dense rock breakthrough pressure measuring device according to an embodiment of the present application;

[0035] FIG10 is a schematic diagram showing the relationship between applied pressure and the average velocity of sound waves passing through a rock sample according to an embodiment of the present application;

[0036] FIG11 is a schematic diagram showing the relationship between temperature and average breakthrough pressure of a rock sample according to an embodiment of the present application;

[0037] FIG12 is a schematic structural diagram of a computer device according to an embodiment of the present application.

[0038] DESCRIPTION OF SYMBOLS IN THE DRAWINGS: 100, cylindrical rock sample; 101, gas injector; 102, gas receiver; 1031, acoustic generator; 1032, acoustic receiver; 104, control assembly; 105, rock sample holder; 106, rock sample sealing sleeve; 107, heating assembly; 108, gas composition detector; 801, gas injection unit; 802, breakthrough position determination unit; 8021, quantity determination module; 803, gas injection pressure increase determination unit; 804, breakthrough pressure determination unit; 8041, recording module; 805, overall breakthrough pressure determination unit; 8051, continued detection module; 806, average breakthrough pressure determination unit; 1002, computer device; 1004, processor; 1006, memory; 1008, drive mechanism; 1010, input / output module; 1012, input device; 1014. Output device; 1016. Presentation device; 1018. Graphical user interface; 1020. Network interface; 1022. Communication link; 1024. Communication bus. DETAILED DESCRIPTION

[0039] In order to enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of this application.

[0040] It should be noted that the terms "first", "second", etc. in this application, the claims, and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the application described herein can be implemented in an order other than those illustrated or described herein. 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.

[0041] This application provides method operation steps as described in the embodiments or flowcharts, but may include more or fewer operation steps based on routine or non-creative work. The order of steps listed in the embodiments is only one way of executing the steps among many steps and does not represent the only execution order. When the actual system or device product is executed, it can be executed in the order or in parallel according to the method shown in the embodiments or the drawings.

[0042] It should be noted that the dense rock breakthrough pressure measurement system and method of the present application can be used in the field of oil and gas field exploration and development, and can also be used in the field of underground gas storage construction.

[0043] Figure 1 is a schematic diagram of a system for measuring breakthrough pressure of dense rock according to an embodiment of the present invention. The system includes a columnar rock sample 100, a gas injector 101, a gas receiver 102, at least one set of acoustic sensors, a control assembly 104, and a gas composition detector 108.

[0044] The gas injector 101 is connected to one end of the columnar rock sample 100 in the width direction and is used to inject gas into the rock sample at an initial gas injection pressure and a preset temperature. In the embodiment of the present application, the injected gas is a gas that does not chemically react with the rock sample under high temperature conditions, including at least one of stable gases such as nitrogen, helium, and argon.

[0045] The gas receiver 102 is connected to the other end of the columnar rock sample 100 in the width direction and is used to collect gas discharged from the end of the columnar rock sample 100. The gas injector 101 and the gas receiver 102 are arranged symmetrically along the long axis of the columnar rock sample 100. The present embodiment does not limit the arrangement type of the gas injector 101 and the gas receiver 102, but it is recommended that they be arranged symmetrically along the long axis of the columnar rock sample 100.

[0046] At least one set of acoustic sensors, each set of acoustic sensors includes an acoustic generator 1031 and an acoustic receiver 1032. In each set of acoustic sensors, the line connecting the acoustic generator 1031 and the acoustic receiver 1032 is perpendicular to the line connecting the gas injector 101 and the gas receiver 102. For example, if the gas injector 101 is connected to one end of the columnar rock sample 100 in the width direction, and the gas receiver 102 is connected to the other end of the columnar rock sample 100 in the width direction, then the acoustic generator 1031 and the acoustic receiver 1032 are respectively arranged on the sideline symmetrically about the long axis of the columnar rock sample 100, and the at least one set of acoustic sensors is arranged at equal intervals along the length direction.

[0047] In the embodiments of the present application, the line connecting the acoustic generator 1031 and the acoustic receiver 1032 may be orthogonal to, that is, perpendicular to, the connection formed by the gas injector 101 and the gas receiver 102. Alternatively, the line connecting the acoustic generator 1031 and the acoustic receiver 1032 may be oblique to the connection formed by the gas injector 101 and the gas receiver 102. The embodiments of the present application do not limit the angle at which the acoustic sensor intersects with the gas receiver or the gas injector.

[0048] In the embodiment of the present application, acoustic generator 1031 is used to transmit acoustic signals of different preset frequencies into columnar rock sample 100. After the acoustic signals propagate through the rock sample, acoustic receiver 1032 collects the acoustic signals and determines the average velocity of the acoustic signals through the rock sample. Because the propagation speed of sound waves in different media varies, with the propagation speed of sound waves in gas significantly slower than in rock, water, and oil, the average velocity of the sound waves through the rock sample as detected by the acoustic receiver will vary if the acoustic signal emitted by the acoustic generator passes through different media within the rock sample.

[0049] In an embodiment of the present application, a control component is used to determine the average velocity of the acoustic signal passing through the rock sample and the breakthrough position of the injected gas within the rock sample based on the acoustic signal passing through the rock sample collected by the acoustic receiver; determine whether to increase the gas injection pressure based on the breakthrough position; if so, increase the gas injection pressure and calculate the average velocity of the acoustic wave passing through the rock sample, repeatedly determining the breakthrough position of the injected gas within the rock sample until the injected gas reaches the end of the rock sample; determine the breakthrough pressure at different acoustic receiver positions of the dense rock sample based on the gas injection pressure corresponding to each acoustic receiver position; determine the overall breakthrough pressure of the rock sample based on the changes in the composition and content of the injected gas recorded by the gas composition detector; and determine the average breakthrough pressure of the rock sample based on the breakthrough pressures at different acoustic receiver positions and the overall breakthrough pressure. The processing flow of the control component in the embodiment of the present application is described in Figure 2 and the corresponding embodiments.

[0050] In an embodiment of the present application, the gas composition detector 108 is used to detect the gas composition and gas content output from the end of the rock sample, with a detection sensitivity higher than 0.01%, and to determine the breakthrough pressure of the entire rock sample based on whether the composition and content of the gas have changed significantly; if so, it is determined that the injected gas has broken through and reached the end of the sample, and the gas injection pressure at this time is determined to be the breakthrough pressure of the entire rock sample; if not, the changes in the gas composition and gas content output from the end of the rock sample are continued to be detected and recorded.

[0051] In other embodiments of the present application, the dense rock breakthrough pressure measurement system further includes: a rock sample holder 105, a rock sample sealing sleeve 106, and a heating assembly 107. The rock sample holder 105 is used to secure the columnar rock sample 100 and apply a certain pressure. The rock sample holder 105 can be expanded and contracted inward by applying lateral pressure and confining pressure, thereby tightly contacting the columnar rock sample 100 with the rock sample sealing sleeve 106 to prevent any gaps. The rock sample sealing sleeve 106 is used to seal the space between the columnar rock sample 100 and the rock sample holder 105. The rock sample sealing sleeve 106 can be made of a plastic, high-temperature, and high-pressure resistant rubber that can withstand temperatures of 1000°C without deformation or decomposition.

[0052] In the embodiment of the present application, a columnar rock sample 100 saturated with oil is placed in a rock sample sealing sleeve 106 and then placed together in a rock sample holder 105. The rock sample holder 105 is applied with lateral pressure and confining pressure to expand and contract inward, and the applied pressure is kept below the rock sample fracture pressure. Gas is injected into the columnar rock sample 100 through the gas injector 101 to test and ensure the sealing of the columnar rock sample 100.

[0053] The heating assembly 107 is used to heat the columnar rock sample 100 to a preset temperature and control the heating rate of the columnar rock sample 100. The gas composition detector 108 is used to detect the composition and content of the injected gas output from the end of the columnar rock sample 100.

[0054] FIG2 is a flow chart of a method for measuring breakthrough pressure of dense rock according to an embodiment of the present application, which specifically includes the following steps:

[0055] Step 201, injecting gas into the rock sample through a gas injector under the action of an initial gas injection pressure and a preset temperature. In an embodiment of the present application, gas is injected into the rock sample through a pressure gauge connected to the gas injector. The pressure gauge provides the gas injection pressure, and under the initial gas injection pressure, the gas is slowly injected into the rock sample and breaks through the rock sample. In other examples of the present application, a heating system provides the required temperature for the measuring system. Specifically, the heating system heats the rock sample to the temperature required for the test and can control the heating rate. The temperature can be adjusted from room temperature to 800°C. In an embodiment of the present application, gas is injected into the rock sample by pre-setting the initial gas injection pressure and the preset temperature.

[0056] Step 202: Based on the acoustic signals collected by each acoustic receiver passing through the rock sample, the average velocity of the acoustic wave through the rock sample and the breakthrough point of the injected gas within the rock sample are determined. In this embodiment of the present application, the acoustic sensor can be controlled to be activated, i.e., enter an operating state, before the gas is injected into the rock sample. Before the gas is injected into the rock sample, the acoustic generator emits a sound wave. After the sound wave passes through the rock sample without gas injection, the acoustic receiver receives the sound wave signal, and the computer or control component calculates the average velocity of the sound wave through the rock sample. This allows the velocity of the sound wave propagating within the rock sample to be determined when no gas is injected.

[0057] After or while gas is injected into the rock sample, the acoustic transmitter emits an acoustic signal into the rock sample. After the acoustic signal passes through the rock sample, the acoustic receiver receives it. When the injected gas reaches the first set of acoustic sensors (the ones closest to the gas injector), the acoustic signal received by the first set of acoustic sensors is the signal that has propagated through the rock sample, oil, and gas. Before the injected gas reaches the first set of acoustic sensors, the acoustic signal received by the acoustic receiver is the signal that has propagated through the solid rock sample and oil. When the injected gas reaches the first set of acoustic sensors but has not yet reached the second set of acoustic sensors, the acoustic signal received by the first acoustic receiver is the signal that has propagated through the rock sample, oil, and gas, while the acoustic signal received by the second acoustic receiver is the signal that has propagated through the rock sample and oil.

[0058] Because the propagation speed of sound waves in gas is significantly slower than that in solid rock, liquid water, or oil, the location of gas in a rock sample can be accurately determined based on the differences in sound wave propagation speeds in different media. Specifically, if the average speed of the sound wave signal passing through the rock sample as received by the acoustic receiver suddenly decreases over a continuous period of time, it indicates that the sound wave has reached the gas and entered the gas at that moment. Therefore, the average speed of the sound wave passing through the rock sample can be used to determine the breakthrough point of the injected gas within the rock sample.

[0059] Step 203 determines whether to increase the gas injection pressure based on the average velocity and the breakthrough position. In this step, if the rock sample is dense, then at a constant gas injection pressure no lower than the overall breakthrough pressure, gas injected from one end of the rock sample can slowly break through to the other end. If the gas injection pressure is lower than the breakthrough pressure, then at the initial gas injection pressure, gas injected from one end of the rock sample will not be able to successfully break through to the other end for a long time. In some cases, gas injected from one end of the rock sample may not be able to break through from the gas injector to the first set of acoustic sensors closest to the gas injector.

[0060] Therefore, it is determined whether the gas injection pressure needs to be increased based on the breakthrough position of the injected gas in the rock sample within the preset time. Among them, the preset time is the normal time required for the gas to break through a certain distance in the rock sample. For example, it is assumed that the time required for nitrogen to break through 5 cm in a dense rock sample (the distance between multiple acoustic receivers can be set to 5 cm) is 2 hours. Then set the preset time to 2 hours, and observe whether the average speed of the sound wave through the rock sample collected and calculated by the acoustic receiver closest to the gas injector within 2 hours changes. Specifically, observe and calculate whether the average speed of the sound wave through the rock sample within 2 hours is significantly reduced. If so, it means that gas has broken through to the position of the acoustic receiver closest to the gas injector within 2 hours.

[0061] Furthermore, it is observed whether the average velocity of the sound waves passing through the rock sample collected and calculated by the second acoustic receiver within the next 2 hours changes significantly. If so, it means that gas has broken through and reached the position of the second acoustic receiver within the 2 hours.

[0062] If yes, step 204 , increase the gas injection pressure and calculate the average velocity of the sound wave passing through the rock sample, and repeatedly determine the breakthrough position of the injected gas in the rock sample until it is determined that the injected gas has reached the end of the rock sample.

[0063] In this step, the pressure is increased at preset boost intervals, essentially increasing the gas injection pressure. This increased pressure changes the motion of the gas within the rock sample, accelerating its breakthrough velocity. The acoustic receivers in each set of acoustic sensors further capture the acoustic signals under these conditions, and a computer or control unit calculates the average velocity of the sound waves through the rock sample.

[0064] Step 205: Determine the breakthrough pressure of the dense rock sample at different acoustic receiver locations based on the gas injection pressure recorded at each acoustic receiver location. In this step, when the average velocity of the acoustic wave passing through the rock sample, collected and calculated over a period of time, decreases significantly, it is determined that gas has broken through and reached the location of that acoustic receiver. The gas injection pressure injected from the gas injector at this time is recorded, and this gas injection pressure is considered the breakthrough pressure of the rock sample at that acoustic receiver location.

[0065] Step 206 determines the overall breakthrough pressure of the rock sample based on the changes in the composition and content of the injected gas recorded by the gas composition detector. In this step, the gas composition detector records the presence of a determination of whether the injected gas has penetrated the entire rock sample, thereby determining the overall breakthrough pressure of the rock sample. If the injected gas has not penetrated the entire rock sample, the overall breakthrough pressure of the rock sample cannot be determined. See Figure 7 for a detailed description of this step.

[0066] Step 207: Determine the average breakthrough pressure of the rock sample based on the breakthrough pressures at different acoustic receiver locations and the overall breakthrough pressure. In this embodiment, after determining the breakthrough pressures at each acoustic receiver location and the overall breakthrough pressure of the rock sample, these two types of breakthrough pressures are combined to determine the average breakthrough pressure of the rock sample.

[0067] This application introduces multiple sets of acoustic emission and acoustic receiving devices, and then obtains the breakthrough pressure of multiple different positions of the same rock sample in one test, and finally takes the average value to obtain a more accurate test result. For example, determine the breakthrough pressure of the rock sample at all acoustic receiver positions as P1, P2, P3...P n , P e is the breakthrough pressure measured at the end of the sample, where n represents the number of acoustic receivers. The average breakthrough pressure of the sample is obtained by summing and averaging the breakthrough pressures at different acoustic receiver locations and the breakthrough pressures measured at the end of the sample.

[0068] FIG3 is a flow chart of a method for determining the breakthrough arrival position of injected gas in a rock sample according to an embodiment of the present application, which specifically includes the following steps:

[0069] Step 301: Determine the number n by which the average velocity of the sound waves passing through the rock sample recorded by each acoustic receiver within a preset period is less than a preset velocity.

[0070] Further determine which acoustic receiver recorded the decrease in the average speed of the sound waves passing through the rock sample. In this step, if the average speed of the sound waves passing through the rock sample collected and calculated within the preset period remains unchanged, changes very little, or fluctuates briefly within a small range, it can be determined that the gas has not broken through to the position of the acoustic receiver within the preset period. In this embodiment of the present application, the preset speed is an average speed that is 5% less than the average speed of the sound waves passing through the rock sample before the gas pressure is added. In some embodiments of the present application, the preset speed can be an average speed that is less than 5% of the average speed of the sound waves passing through the rock sample before the gas pressure is added. The specific size and range of the preset speed are not limited in this embodiment of the present application.

[0071] For example, the acoustic receivers counted from one end of the gas injector are numbered 1, 2, 3, 4, 5, and 6, which are acoustic receivers with increasing distances from the gas injector.

[0072] As shown in Table 1: Before the gas pressure was added, the acoustic receiver numbered 1 recorded an average speed of 1946 m / s for the propagation of sound waves in the oil-saturated rock sample. At a certain moment, it was detected and calculated that the average speed of the sound waves passing through the rock sample decreased by 5% to 1847 m / s.

[0073] Table 1 Relationship between the average velocity of acoustic waves passing through rock samples and breakthrough pressure

[0074] Step 302: If n = 0, it is determined that the injected gas has not broken through to reach the acoustic receiver closest to the gas injector, indicating that the gas has not broken through within the preset cycle time in the rock sample, or the breakthrough is very slow and has not reached the position of the first acoustic receiver closest to the gas injector.

[0075] Step 303: If n = 1, the position of the first acoustic receiver is determined as the position where the injected gas breaks through in the rock sample, indicating that the gas has only passed through the first acoustic receiver within the preset cycle time.

[0076] Step 304: If n > 1 and n < N, where N represents the total number of acoustic receivers, the position of the acoustic receiver closest to the gas receiver is determined as the position where the injected gas breaks through in the rock sample. In this step, the average speed of the sound waves collected by multiple acoustic receivers passing through the rock sample is lower than the preset speed, indicating that within a certain period of time, the gas breaks through in the rock sample and passes through multiple acoustic sensors. It is determined that the current breakthrough position of the gas in the rock sample is the position of the acoustic receiver that is farthest from the gas injector and closest to the gas receiver. For example, if the number of acoustic receivers recording a decrease in the average speed of the sound waves passing through the rock sample is 2, it means that the gas has passed through the second acoustic sensor, and the position where the gas breaks through in the rock sample is the position of the second acoustic receiver.

[0077] Step 305: If n = N, based on the composition and content of the injected gas output from the end of the rock sample detected by the gas composition detector, the position where the injected gas breaks through in the rock sample is determined.

[0078] Figure 4 shows a flowchart of another method for determining the breakthrough arrival position according to an embodiment of the present application, which specifically includes the following steps:

[0079] Step 401: Determine whether the increase rate of the content of the injected gas output from the end of the rock sample exceeds a preset threshold.

[0080] Among them, the preset threshold is used to determine whether the injected gas output from the end of the rock sample has increased significantly.

[0081] Step 402: When it does not exceed the preset threshold, the position of the last acoustic receiver is determined as the position where the injected gas breaks through in the rock sample. In this step, the increase rate of the content of the injected gas does not exceed the preset threshold, indicating that the content of the injected gas has not increased significantly or has hardly changed.

[0082] In the embodiment of the present application, it is set that the last acoustic receiver is located on the left side of the end of the sample, that is, the gas first breaks through the Nth acoustic receiver and then breaks through to the end of the rock sample. N represents the total number of acoustic receivers. When the content of the injected gas output from the end of the rock sample does not increase significantly, the gas breakthrough position should be between the position of the last acoustic receiver and the end of the rock sample, and the breakthrough position can be regarded as the position of the last acoustic receiver.

[0083] Step 403, if it exceeds the preset threshold, determine whether the gas injection pressure when the content increase rate of the output injected gas exceeds the preset threshold is the initial gas injection pressure.

[0084] In this step, if the content of the injected gas output from the end of the rock sample increases significantly, then determine the magnitude of the gas injection pressure when the content increases significantly.

[0085] Step 404, if it exceeds the preset threshold, if the gas injection pressure at this time is the initial gas injection pressure, terminate the test. In the case of this step, the content increase rate of the injected gas output from the end of the rock sample exceeds the preset threshold, indicating that the content of the injected gas increases significantly. But at this time, the gas injection pressure is the initial gas injection pressure, indicating that the sample has cracks, and the experiment is terminated.

[0086] Step 405, if the gas injection pressure is the pressure after adjustment, determine that the injected gas breaks through to the end in the rock sample. The content of the injected gas output from the end of the rock sample increases significantly, and the gas injection pressure is the pressure after adjustment, determine that the injected gas breaks through to the end in the rock sample, and the experiment is successfully completed.

[0087] Figure 5 shows a flowchart of a method for determining whether to increase the gas injection pressure in an embodiment of the present application, which specifically includes the following steps:

[0088] Step 501, when the average speed of the sound waves recorded by all acoustic receivers passing through the rock sample is not lower than the preset speed, increase the gas injection pressure. In the embodiment of the present application, when the average speed of the sound waves detected by all acoustic receivers passing through the rock sample is not lower than the preset speed, the injected gas does not break through to the position of any acoustic receiver. That is to say, after the gas is injected into the rock sample, the breakthrough is extremely slow, and even does not reach the position of the first acoustic receiver.

[0089] Step 502, when the average speed of the sound waves recorded by some acoustic receivers passing through the rock sample is partially lower than the preset speed, and the breakthrough position of the injected gas in the rock sample does not change within the preset period, increase the gas injection pressure. In this step, when the number of the average speeds of the recorded sound waves passing through the rock sample that are partially lower than the preset speed, that is, the number n of acoustic receivers with an average speed lower than the preset speed satisfies n≥1 and n<N (N is the total number of all acoustic receivers).

[0090] In this step, if the injected gas breakthrough point within the rock sample remains unchanged within the preset period, it can be interpreted as indicating that the injected gas breakthrough rate is lower than normal. For example, assume that nitrogen typically takes two hours to break through 5 centimeters of rock in a dense rock sample. However, data collected by the acoustic receiver reveals that nitrogen has barely broken through within two hours, indicating that the rock throat at this location is narrowing. Therefore, it is necessary to increase the gas injection pressure to accelerate the breakthrough rate within the rock sample and restore the breakthrough rate to normal.

[0091] Step 503: When the average velocity of the sound waves passing through the rock sample recorded by the acoustic receivers is all lower than the preset velocity, if the gas injection pressure is the initial gas injection pressure, the experiment is terminated; if the gas injection pressure is the increased pressure, there is no need to adjust the gas injection pressure. In some embodiments of the present application, if the gas injection pressure is the initial gas injection pressure, it indicates that the sample has developed fractures and poor sealing properties, making it unsuitable for this experimental test, and the experiment can be terminated immediately. If it is determined that the injected gas has broken through to the last acoustic receiver position, there is no need to adjust the injected gas pressure, and the experiment can be completed by appropriately extending the experimental time.

[0092] FIG6 is a flow chart of a method for determining the breakthrough pressure of a dense rock sample at different acoustic receiver positions according to an embodiment of the present application, which specifically includes the following steps:

[0093] Step 601: When the injected gas breaks through and reaches each acoustic receiver, the gas injection pressure is recorded. According to the aforementioned steps, when each acoustic receiver detects that the average velocity of the sound wave passing through the rock sample begins to decrease and falls below a predetermined velocity range, the injected gas is determined to have broken through and reached the acoustic receiver location. The control component records the gas injection pressure in this state.

[0094] Step 602: The gas injection pressure at which the injected gas breaks through and reaches each acoustic receiver position is determined as the breakthrough pressure of the rock sample at different acoustic receiver positions.

[0095] FIG7 is a flow chart of a method for determining the overall breakthrough pressure of a dense rock sample according to an embodiment of the present application, which specifically includes the following steps:

[0096] In step 701, when the increase in the composition and content of the injected gas discharged from the end of the rock sample exceeds a preset threshold and the gas injection pressure at this time is higher than the initial gas injection pressure, it is determined that the injected gas has reached the end of the rock sample. The gas injection pressure at this time is recorded as the breakthrough pressure of the entire rock sample. In this step, once the injected gas has reached the end of the rock sample, there is no need to adjust the injected gas pressure, and the experiment can be completed by appropriately extending the experiment time.

[0097] In step 702, if the increase in the composition and content of the injected gas discharged from the end of the sample does not exceed a preset threshold, the changes in the composition and content of the gas discharged from the end of the sample are continuously detected and recorded. If the gas detector does not detect a significant change in the gas discharged from the end of the sample, it indicates that the injected gas has not penetrated the intact sample, and the changes in the composition and content of the injected gas discharged from the end of the sample are continuously detected.

[0098] In the embodiment of the present application, determining the average breakthrough pressure of the rock sample using the determined breakthrough pressures at different acoustic receiver positions and the overall breakthrough pressure of the rock sample includes: recording the breakthrough pressures at different acoustic receiver positions and the overall breakthrough pressure; specifically, determining the average breakthrough pressure using the following formula:

[0099] Among them, P ave represents the average breakthrough pressure, n represents the number of times the average speed of the sound wave passing through the rock sample recorded by each acoustic receiver within the preset period is less than the preset speed, P1 is the breakthrough pressure of the rock sample section at the connection position of the first group of sound transmitters and sound receivers, P2 is the breakthrough pressure of the rock sample section at the connection position of the second group of sound transmitters and sound receivers, P n is the breakthrough pressure of the rock sample section at the connection line between the nth group of sound transmitters and sound receivers, P e The breakthrough pressure is measured at the end of the rock sample. This application introduces multiple sets of acoustic emission and acoustic reception devices to obtain the breakthrough pressure at multiple locations on the same rock sample and the breakthrough pressure of the entire rock sample in a single test. Taking the average of these values ​​can obtain a more accurate breakthrough pressure test result.

[0100] FIG8 is a schematic diagram of the structure of a dense rock breakthrough pressure measurement device according to an embodiment of the present application. This figure illustrates the basic structure of the dense rock breakthrough pressure measurement device. The functional units and modules therein can be implemented using software, or a general-purpose chip or a specific chip can be used to implement dense rock breakthrough pressure measurement. The device specifically includes:

[0101] The gas injection unit 801 is used to inject gas into the rock sample through a gas injector under the action of an initial gas injection pressure and a preset temperature;

[0102] A breakthrough position determination unit 802 is used to determine the average speed of the sound wave passing through the rock sample and the breakthrough position of the injected gas in the rock sample based on the acoustic signals passing through the rock sample collected by each acoustic receiver;

[0103] The gas injection pressure increase determination unit 803 is used to determine whether to increase the gas injection pressure based on the average velocity and the breakthrough position; if so, the gas injection pressure is increased and the average velocity of the sound wave passing through the rock sample is calculated, and the breakthrough position of the injected gas in the rock sample is repeatedly determined until the injected gas breaks through and reaches the end of the rock sample;

[0104] a breakthrough pressure determination unit 804 for determining the breakthrough pressure at different acoustic receiver positions of the rock sample based on the gas injection pressure corresponding to each acoustic receiver position;

[0105] The overall breakthrough pressure determination unit 805 is used to determine the overall breakthrough pressure of the rock sample based on the change results of the composition and content of the injected gas output from the end of the rock sample recorded by the gas composition detector;

[0106] Average breakthrough pressure determination unit 806 is used to determine the average breakthrough pressure of the rock sample based on the breakthrough pressures at different acoustic receiver locations and the overall breakthrough pressure. This application enables measurement of the breakthrough pressures at different locations and the overall breakthrough pressure when gas breaks through a dense rock sample under different temperature conditions. Furthermore, by calculating the average breakthrough pressure, the measurement accuracy of the dense rock breakthrough pressure is improved. This provides an effective means for evaluating caprocks for conventional oil and gas, assessing the sealing properties of interlayers for in-situ conversion and development of unconventional shale oil, and evaluating the effectiveness of barrier layers in underground gas storage.

[0107] As an embodiment of the present application, reference may also be made to FIG9 , which is a schematic diagram of the specific structure of the dense rock breakthrough pressure measurement device of this embodiment. As an embodiment of the present application, the breakthrough position determination unit 802 further includes:

[0108] The quantity determination module 8021 is used to determine the number of times that the average speed of the sound waves passing through the rock sample recorded by each acoustic receiver within a preset period is less than a preset speed;

[0109] As an embodiment of the present application, the breakthrough pressure determination unit 804 further includes:

[0110] The recording module 8041 is used to record the gas injection pressure when the injected gas breaks through and reaches each acoustic receiver position;

[0111] As an embodiment of the present application, the overall breakthrough pressure determination unit 805 further includes:

[0112] The continued detection module 8051 is used to continue detecting and recording changes in the composition and content of the gas output from the end of the rock sample when the composition and content of the injected gas discharged from the end of the rock sample do not change significantly.

[0113] FIG10 is a schematic diagram showing the relationship between applied pressure and the average velocity of sound waves passing through a rock sample according to an embodiment of the present application.

[0114] A 10cm long dense sandstone plunger was heated to 350°C and held at that temperature for 24 hours. The relationship between the inlet pressure corresponding to the first set of acoustic transmitters and receivers and the average velocity of the sound waves passing through the rock sample was obtained after continuous pressure application. Figure 10 shows that the average velocity of the sound waves passing through the rock sample, as detected by the receivers, initially decreases slowly. When the pressure reaches 4.31 MPa, the average velocity decreases rapidly, and then slowly decreases as the applied pressure increases.

[0115] FIG11 is a schematic diagram showing the relationship between temperature and average breakthrough pressure of a rock sample according to an embodiment of the present application.

[0116] In the examples of the present application, a piece of dense sandstone was measured at temperatures of 25°C, 50°C, 100°C, 150°C, 200°C, 250°C, 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, and 600°C, respectively, to obtain a graph showing the relationship between the average breakthrough pressure and temperature of the entire rock sample. As can be seen from the figure, as the temperature increases, the average breakthrough pressure of the dense sandstone shows a trend of first increasing and then decreasing, with the turning point at a temperature of approximately 200°C. In other words, when the temperature is around 200°C, the average breakthrough pressure of the rock sample reaches its maximum. The examples of the present application achieve the measurement of the breakthrough pressure of dense rock at different temperature conditions and at different positions, and the measurement of the overall breakthrough pressure when gas breaks through the rock sample. By obtaining the average breakthrough pressure, the measurement accuracy of the breakthrough pressure of dense rock is greatly improved. It provides a technical means for measuring the breakthrough pressure at different positions and the overall breakthrough pressure of the rock sample under different temperature conditions, as well as for obtaining the high-precision average breakthrough pressure.

[0117] As shown in FIG12 , a computer device is provided in an embodiment of the present application. The present application's dense rock breakthrough pressure measurement can be performed by the computer device. Computer device 1202 may include one or more processors 1204, such as one or more central processing units (CPUs), each of which may implement one or more hardware threads. Computer device 1202 may also include any memory 1206 for storing any type of information, such as code, settings, data, and the like. For example, and without limitation, memory 1206 may include any one or more combinations of the following: any type of RAM, any type of ROM, a flash memory device, a hard disk, an optical disk, and the like. More generally, any memory may use any technology to store information. Furthermore, any memory may provide volatile or non-volatile retention of information. Furthermore, any memory may represent a fixed or removable component of computer device 1202. In one embodiment, when processor 1204 executes associated instructions stored in any memory or combination of memories, computer device 1202 may perform any operation of the associated instructions. The computer device 1202 also includes one or more drive mechanisms 1208 for interacting with any storage, such as a hard disk drive mechanism, an optical disk drive mechanism, and the like.

[0118] The computer device 1202 may also include an input / output module 1210 (I / O) for receiving various inputs (via input devices 1212) and for providing various outputs (via output devices 1214). A specific output mechanism may include a presentation device 1216 and an associated graphical user interface (GUI) 1218. In other embodiments, the input / output module 1210 (I / O), input devices 1212, and output devices 1214 may not be included, and the computer device 1202 may simply be a computer device in a network. The computer device 1202 may also include one or more network interfaces 1220 for exchanging data with other devices via one or more communication links 1222. One or more communication buses 1224 couple the components described above together.

[0119] The communication link 1222 may be implemented in any manner, for example, via 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 1222 may include any combination of hardwired links, wireless links, routers, gateway functions, name servers, etc., governed by any protocol or combination of protocols.

[0120] Corresponding to the methods in Figures 2 to 7, an embodiment of the present application further 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.

[0121] An embodiment of the present application also provides a computer-readable instruction, wherein when a processor executes the instruction, the program therein causes the processor to execute the method shown in Figures 2 to 7.

[0122] It should be understood that in the various embodiments of the present application, 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 the present application.

[0123] It should also be understood that in the embodiments of this application, the term "and / or" is merely a description of the relationship between associated objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, or B exists alone. Furthermore, the character " / " in this application generally indicates that the associated objects are in an "or" relationship.

[0124] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed in this application 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 to be beyond the scope of this application.

[0125] Those skilled in the art will 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.

[0126] In the several embodiments provided in this application, 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 merely schematic. For example, the division of units is merely a logical function division. In actual implementation, there may be other division methods, 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.

[0127] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments of the present application.

[0128] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0129] 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 the present application 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 for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0130] Specific embodiments are used in this application to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this application should not be understood as limiting this application.

Claims

1. A dense rock breakthrough pressure measurement system, characterized in that: The system includes: a rock sample, a gas injector, a gas receiver, a gas composition detector, at least one set of acoustic sensors and a control component; The gas injector is connected to one end of the rock sample in the width direction and is used to inject gas into the rock sample at an initial gas injection pressure and a preset temperature; The gas receiver is connected to the other end of the rock sample in the width direction and is used to collect the gas discharged from the end of the rock sample. The gas injector and the gas receiver are symmetrically arranged along the long axis direction of the rock sample. Gas composition detector, used to detect the composition and content of the injected gas output from the end of the rock sample; The at least one group of acoustic sensors includes: an acoustic generator and an acoustic receiver, wherein a line formed by the acoustic generator and the acoustic receiver in each group of acoustic sensors intersects a line formed by the gas injector and the gas receiver, wherein the acoustic generator is used to send acoustic signals of different preset frequencies into the rock sample, and the acoustic receiver is used to collect the acoustic signals after propagation in the rock sample; A control component is used to determine the average speed of the acoustic signal passing through the rock sample and the breakthrough position of the injected gas in the rock sample based on the acoustic signal collected by the acoustic receiver passing through the rock sample; determine whether to increase the initial gas injection pressure based on the breakthrough position; if so, increase the initial gas injection pressure and calculate the average speed of the acoustic wave passing through the rock sample, and repeatedly determine the breakthrough position of the injected gas in the rock sample until the injected gas breaks through and reaches the end of the rock sample; determine the breakthrough pressure of different acoustic receiver positions of the dense rock sample based on the gas injection pressure corresponding to each acoustic receiver position; determine the overall breakthrough pressure of the rock sample based on the change results of the composition and content of the injected gas recorded by the gas composition detector; determine the average breakthrough pressure of the rock sample based on the breakthrough pressures at different acoustic receiver positions and the overall breakthrough pressure.

2. The dense rock breakthrough pressure measurement system according to claim 1, characterized in that: The system further comprises: A rock sample holder, used for fixing the rock sample; A rock sample sealing sleeve, used for sealing the space between the rock sample and the rock sample holder; The heating component is used to heat the rock sample to a preset temperature and control the heating rate of the rock sample.

3. The dense rock breakthrough pressure measurement system according to claim 2, characterized in that: The rock sample sealing sleeve is made of high temperature and high pressure resistant material.

4. A method for measuring breakthrough pressure of dense rock, characterized in that: The method is applied to the dense rock breakthrough pressure measurement system according to any one of claims 1 to 3, comprising: Injecting gas into the rock sample through a gas injector under the action of an initial gas injection pressure and a preset temperature; According to the acoustic signals passing through the rock sample collected by each acoustic receiver, the average speed of the sound wave passing through the rock sample and the breakthrough position of the injected gas in the rock sample are determined; determining whether to increase the gas injection pressure according to the average speed and the breakthrough position; If yes, increase the gas injection pressure and calculate the average speed of the sound wave passing through the rock sample, and repeatedly determine the breakthrough position of the injected gas in the rock sample until the injected gas breaks through and reaches the end of the rock sample; Determine the breakthrough pressure of different acoustic receiver positions of the rock sample according to the gas injection pressure corresponding to each acoustic receiver position; Determine the overall breakthrough pressure of the rock sample based on the changes in the composition and content of the injected gas output from the end of the rock sample recorded by the gas composition detector; Determine the average breakthrough pressure of the rock sample based on the breakthrough pressures at different positions of the acoustic receivers and the overall breakthrough pressure.

5. The method for measuring breakthrough pressure of dense rock according to claim 4, characterized in that: Determine the average velocity of the sound wave passing through the rock sample and the breakthrough position of the injected gas in the rock sample, including: Determine the number n of the average velocities of the sound waves passing through the rock sample recorded by each acoustic receiver within a preset period that are less than the preset velocity; if n = 0, determine that the injected gas has not broken through to the acoustic receiver closest to the gas injector in terms of distance; If n = 1, determine the position of the first acoustic receiver as the breakthrough position of the injected gas in the rock sample; If n > 1 and n < N, where N represents the total number of acoustic receivers, take the position of the acoustic receiver closest to the gas receiver among the acoustic receivers that record the average velocity of the sound wave passing through the rock sample to be less than the preset velocity as the breakthrough position of the injected gas in the rock sample; If n = N, determine the breakthrough position of the injected gas in the rock sample according to the composition and content of the injected gas output from the end of the rock sample detected by the gas composition detector.

6. The method for measuring breakthrough pressure of dense rock according to claim 5, characterized in that: Determine the breakthrough position of the injected gas in the rock sample according to the composition and content of the injected gas output from the end of the rock sample detected by the gas composition detector, including: Judge whether the increase in the content of the injected gas output from the end of the rock sample exceeds a preset threshold; If it does not exceed the preset threshold, determine the position of the last acoustic receiver as the breakthrough position of the injected gas in the rock sample; If it exceeds the preset threshold, judge whether the gas injection pressure when the increase in the content of the output injected gas exceeds the preset threshold is the initial gas injection pressure; If the gas injection pressure is the initial gas injection pressure, terminate the experiment; If the gas injection pressure is the adjusted pressure, determine that the injected gas breaks through to the end in the rock sample.

7. The method for measuring breakthrough pressure of dense rock according to claim 4, characterized in that: Determine the breakthrough pressures at different positions of the acoustic receivers of the tight rock sample according to the gas injection pressures recorded at each acoustic receiver position: When the injected gas breaks through to each acoustic receiver position, record the gas injection pressure; Record the gas injection pressures at which the injected gas breaks through to the positions of each acoustic receiver as the breakthrough pressures at these positions.

8. The method for measuring breakthrough pressure of dense rock according to claim 4, characterized in that: Determine whether to adjust the gas injection pressure according to the average velocity and the breakthrough position, including: When the average velocities of the sound waves passing through the rock sample recorded by all acoustic receivers are not lower than the preset velocity, increase the gas injection pressure; When the average velocities of the sound waves passing through the rock sample recorded by some acoustic receivers are lower than the preset velocity and the breakthrough position of the injected gas in the rock sample does not change within a preset period, increase the gas injection pressure; When the average velocities of the sound waves passing through the rock sample recorded by all acoustic receivers are lower than the preset velocity, if the gas injection pressure is the initial gas injection pressure, terminate the test; if the gas injection pressure is the adjusted pressure, there is no need to adjust the gas injection pressure anymore.

9. The method for measuring breakthrough pressure of dense rock according to claim 4, characterized in that: Determine the overall breakthrough pressure of the rock sample by using the change results of the composition and content of the injected gas output from the end of the rock sample recorded by the gas composition detector, including: When the increase in the composition and content of the injected gas discharged from the end of the rock sample exceeds the preset threshold, and the gas injection pressure at this time is higher than the initial gas injection pressure, it is determined that the injected gas has broken through and reached the end of the sample, and the gas injection pressure at this time is recorded as the breakthrough pressure of the entire rock sample; When the increase in the composition and content of the injected gas discharged from the end of the rock sample does not exceed the preset threshold, the changes in the composition and content of the gas output from the end of the rock sample continue to be detected and recorded.

10. The method for measuring breakthrough pressure of dense rock according to claim 4, characterized in that: Using the determined breakthrough pressures at different acoustic receiver locations of the rock sample and the overall breakthrough pressure, the average breakthrough pressure of the rock sample is determined to include: Record the breakthrough pressure at different acoustic receiver positions and the overall breakthrough pressure; The average breakthrough pressure is determined using the following formula: Among them, P ave represents the average breakthrough pressure, and n represents the sound waves passing through the rock recorded by each acoustic receiver within a preset period. The number of samples with an average velocity less than the preset velocity, P1 is the breakthrough pressure of the cross section of the rock sample at the connection position of the first group of sound transmitters and sound receivers, P2 is the breakthrough pressure of the cross section of the rock sample at the connection position of the second group of sound transmitters and sound receivers, P n is the breakthrough pressure of the rock sample section at the connection line between the nth group of sound transmitters and sound receivers, P e The breakthrough pressure of the entire rock sample is measured at the end of the rock sample.

11. A dense rock breakthrough pressure measuring device, characterized in that: The device comprises: A gas injection unit, used to inject gas into the rock sample through a gas injector under the action of an initial gas injection pressure and a preset temperature; A breakthrough position determination unit, used to determine the average speed of the sound wave passing through the rock sample and the breakthrough position of the injected gas in the rock sample according to the sound signals passing through the rock sample collected by each acoustic receiver; a gas injection pressure increase determination unit, used to determine whether to increase the gas injection pressure according to the average speed and the breakthrough position; if so, increase the gas injection pressure and calculate the average speed of the sound wave passing through the rock sample, and repeatedly determine the breakthrough position of the injected gas in the rock sample until the injected gas breaks through and reaches the end of the rock sample; a breakthrough pressure determination unit, for determining the breakthrough pressures at different acoustic receiver positions of the rock sample according to the gas injection pressure corresponding to each acoustic receiver position; The overall breakthrough pressure determination unit is used to determine the overall breakthrough pressure of the rock sample according to the change results of the composition and content of the injected gas output from the end of the rock sample recorded by the gas composition detector; The average breakthrough pressure determination unit is used to determine the average breakthrough pressure of the rock sample according to the breakthrough pressures at different acoustic receiver positions and the overall breakthrough pressure.

12. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 4 to 10 is implemented.

13. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 4 to 10 is implemented.

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