Simulation measurement device and method for methane lateral sealing and storage capacity of shale formation

Abstract

The invention is suitable for the technical field of shale gas exploration and development, and provides a shale formation methane lateral sealing capacity simulation measurement device and method.The device comprises a methane gas tank, a pressurization gas injection device, a high-pressure displacement device, a gas collection device and a measurement device; the methane gas tank is connected with the pressurizing gas injection device through a gas conveying pipeline; the high-pressure displacement device comprises a constant-temperature box, a metal core holder and a second metal piston are arranged in the constant-temperature box, and a first hydraulic pump communicated with a hydraulic medium is further arranged on one side of the constant-temperature box; the gas collecting device is connected with one end, far away from the pressurizing gas injection device, of the rock core sample; the measuring device is connected with the gas collecting device. The device can simulate the temperature and pressure conditions of formation conditions, can measure the lateral sealing capacity of shale to methane gas, and is wide in measurement range and high in monitoring precision.

Description

Technical Field

[0001] The present invention belongs to the technical field of shale gas exploration and development, and in particular relates to a device and method for simulating and measuring the lateral methane storage capacity of a shale formation. Background Art

[0002] Shale gas is an unconventional natural gas that exists in organic-rich shale formations in adsorbed and free states. Its main component is methane, and it has the characteristics of clean, low-carbon, and great resource potential. China's recoverable shale gas resources amount to 20 trillion cubic meters, mainly distributed in the Sichuan Basin, Ordos Basin and other regions. Its development is of great significance to optimizing the energy structure and ensuring energy security. Globally, shale gas has become a key transition resource for energy transformation. The preservation conditions of shale gas directly determine the economic value of the gas reservoir. Its sealing evaluation requires comprehensive geological factors (such as roof and floor conditions, structural stability) and microscopic mechanisms (such as pore structure and capillary force). For example, the Wufeng Formation-Longmaxi Formation shale in the Sichuan Basin has a pore structure dominated by nanothroats due to its high organic matter content and low permeability. Combined with the low-speed diffusion effect caused by the presence of bound water and capillary force sealing, an effective self-sealing system has been constructed.

[0003] Existing studies on shale gas sealing capacity mostly focus on vertical sealing capacity, mainly through nuclear magnetic resonance, nitrogen adsorption and other experiments to simulate pore structure and adsorption characteristics, or to evaluate fault stability based on ground stress and rock mechanics parameters. However, existing technologies have significant shortcomings: most experiments do not integrate real formation conditions, and lack dynamic evaluation of lateral sealing mechanisms. For example, the test pressure of traditional isothermal adsorption experiments is mostly lower than 15MPa, and the temperature is also lower than the formation temperature, while methane in shale reservoirs is usually in a supercritical state, resulting in deviations in the adsorption capacity assessment based on the Langmuir equation. In addition, existing models do not fully consider the long-term impact of fracturing, gas production and other operations on lateral sealing during the development process, especially the interaction between bedding fractures and horizontal permeability.

[0004] In view of the above problems, it is urgent to develop a device and method for simulating and measuring the lateral storage capacity of methane in shale formations. Summary of the invention

[0005] The purpose of the embodiments of the present invention is to provide a device and method for simulating and measuring the lateral storage capacity of methane in a shale formation, aiming to solve the problems raised in the above-mentioned background technology.

[0006] The embodiment of the present invention is implemented as follows: a shale formation methane lateral storage capacity simulation measurement device, including a methane gas tank, a pressurized gas injection device, a high-pressure displacement device, a gas collection device and a measurement device;

[0007] The methane gas tank is connected to the pressurized gas injection device through a gas pipeline, and the gas pipeline between the methane gas tank and the pressurized gas injection device is also provided with a first vent valve, and the pressurized gas injection device is used to pressurize the gas delivered by the methane gas tank and deliver it to the high-pressure displacement device;

[0008] The high-pressure displacement device comprises a thermostatic box, in which a metal core clamp for clamping the core sample along the axial direction of the core sample and a second metal piston for clamping the two ends of the core sample are arranged, the metal core clamp is in contact with the core sample through a rubber sleeve, and a hydraulic medium is arranged between the metal core clamp and the rubber sleeve, and a first hydraulic pump connected to the hydraulic medium is also arranged on one side of the thermostatic box;

[0009] The gas collecting device is connected to one end of the core sample away from the pressurized gas injection device, and is used to receive the methane gas overflowed from the pressurized gas injection device, and convert the amount of the overflowed methane gas into liquid weight by a water displacement method;

[0010] The measuring device is connected to the gas collecting device and is used to measure the weight of the liquid discharged by the gas collecting device.

[0011] A further technical solution is that the pressurized gas injection device includes a gas collecting metal tank, the top of which is connected to the methane gas tank, the top of which is also connected to one side of the core sample through a gas pipeline, and a third ventilation valve is also provided on the gas pipeline between the gas collecting metal tank and the high-pressure displacement device, the top of the gas collecting metal tank is also connected to a vacuum pump through a gas pipeline, and a second ventilation valve is also provided on the gas pipeline between the gas collecting metal tank and the vacuum pump, a first metal piston is provided in the gas collecting metal tank, hydraulic oil is provided in the area below the first metal piston in the gas collecting metal tank, and a second hydraulic pump connected to the hydraulic oil is also provided on one side of the gas collecting metal tank.

[0012] In a further technical solution, the gas collecting device comprises a gas collecting bottle, the gas collecting bottle contains measuring water, the side of the core sample away from the pressurized gas injection device is connected to the top of the gas collecting bottle through a gas transmission pipeline, the top of the gas collecting bottle is also connected to the measuring device through a drainage pipeline, and one end of the drainage pipeline is inserted into the measuring water;

[0013] An air pump is also provided on one side of the gas collecting bottle. The air pump is connected to the gas collecting bottle through a gas supply pipeline, and a fourth ventilation valve is also provided on the gas supply pipeline.

[0014] According to a further technical solution, the measuring device comprises a high-precision balance, on which a container containing measuring water is placed, and a silicone oil layer is also provided in the container to prevent the external environment from affecting the weight of the measuring water.

[0015] A further technical solution also includes a pressure control module, which is connected to the first hydraulic pump and the second hydraulic pump at the same time, and is used for electronically controlling the pressure setting, pressurization and pressure relief of the first hydraulic pump and the second hydraulic pump.

[0016] A further technical solution also includes a flow monitoring module, which is connected to the high-precision balance and is used for electronically controlling operations such as zeroing, detection, stopping and data export of the high-precision balance.

[0017] Another object of an embodiment of the present invention is to provide a method for simulating and measuring the methane lateral storage capacity of a shale formation, based on the above-mentioned device for simulating and measuring the methane lateral storage capacity of a shale formation, comprising the following steps:

[0018] Step 1: Collect natural shale rock from the borehole and drill a cylindrical core sample along the horizontal lamina direction. The shale lamina direction is consistent with the long axis direction of the cylinder;

[0019] Step 2: Load the cylindrical core sample into the high-pressure displacement device and close all ventilation valves;

[0020] Step 3: Setting the pressure of the first hydraulic pump to the formation pressure condition through the pressure control module, starting the first hydraulic pump to increase the confining pressure of the metal core holder to the formation pressure condition, and setting the temperature of the thermostatic box to the formation temperature;

[0021] Step 4: Open the second vent valve and the third vent valve, turn on the vacuum pump to evacuate the gas collecting metal tank and the upstream pipeline, stop the vacuum when the pressure reaches -0.1MPa, and close all vent valves;

[0022] Step 5: Put a proper amount of water into the measuring device, and drip silicone oil to ensure that the water does not evaporate; open the fourth ventilation valve, turn on the air pump, let a proper amount of water flow back from the measuring device into the gas collecting device, close the fourth ventilation valve and the air pump, wait for the high-precision balance value to stabilize, and control the high-precision balance value to return to zero in the flow monitoring module;

[0023] Step 6: Open the first vent valve to allow the gas in the methane gas tank to fill the pressurized gas injection device, and then close the first vent valve;

[0024] Step 7: Open the third ventilation valve, set the pressure program of the second hydraulic pump through the pressure control module, turn on the second hydraulic pump, and gradually increase the internal pressure of the boosting and gas injection device according to the set program;

[0025] Step 8: The flow monitoring module is used to record the changes of the high-precision balance to analyze the gas sealing ability of the core sample under a certain temperature and confining pressure.

[0026] The embodiment of the present invention provides a device and method for simulating and measuring the methane lateral storage capacity of a shale formation, and its beneficial effects are as follows:

[0027] (1) It can simulate the temperature and pressure conditions of the formation and measure the lateral storage capacity of shale for methane gas;

[0028] (2) The methane injection pressure is increased by the booster gas injection device to break through the maximum pressure of the methane gas tank, up to 60 MPa, corresponding to the formation fluid pressure at a depth of about 6,000 meters;

[0029] (3) The mass of the gas-discharged water (taking advantage of the fact that methane is insoluble in water) is weighed using a high-precision balance to achieve the effect of calculating the amount of methane passing through a small volume with high precision;

[0030] (4) Through the pressure control module and the flow monitoring module, the time-pressure-flow relationship can be recorded in real time to accurately evaluate the lateral methane gas storage capacity of shale. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A schematic diagram of the structure of a device for simulating and measuring the lateral storage capacity of methane in a shale formation provided by an embodiment of the present invention;

[0032] Figure 2 The time-pressure-absolute flow rate curve of the shale sample with Sw = 100%;

[0033] Figure 3 The time-pressure-relative flow rate curve of the shale sample with Sw = 100%;

[0034] Figure 4 Time-pressure-flow curves for several different shale samples.

[0035] In the attached figure: methane gas tank 1; pressurized gas injection device 2; gas collecting metal tank 21; first metal piston 22; hydraulic oil 23; high-pressure displacement device 3; metal core clamp 31; second metal piston 32; core sample 33; hydraulic medium 34; rubber sleeve 35; constant temperature box 36; gas collecting device 4; gas collecting bottle 41; measuring water 42; measuring device 5; silicone oil layer 51; measuring water 52; high-precision balance 53; first hydraulic pump 6; second hydraulic pump 7; vacuum pump 8; air pump 9; pressure control module 10; flow monitoring module 11; gas transmission pipeline 12; first ventilation valve F1; second ventilation valve F2; third ventilation valve F3; fourth ventilation valve F4. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0037] The specific implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0038] like Figure 1 As shown, a shale formation methane lateral storage capacity simulation measurement device provided by an embodiment of the present invention comprises a methane gas tank 1, a pressurized gas injection device 2, a high-pressure displacement device 3, a gas collection device 4 and a measurement device 5;

[0039] The methane gas tank 1 is connected to the pressurized gas injection device 2 through a gas pipeline 12, and the gas pipeline 12 between the methane gas tank 1 and the pressurized gas injection device 2 is also provided with a first ventilation valve F1, and the pressurized gas injection device 2 is used to pressurize the gas delivered by the methane gas tank 1 and deliver it to the high-pressure displacement device 3;

[0040] The high-pressure displacement device 3 includes a thermostatic box 36, in which a metal core clamp 31 for clamping the core sample 33 along the axial direction of the core sample 33 and a second metal piston 32 for clamping the two ends of the core sample 33 are arranged. The metal core clamp 31 is in contact with the core sample 33 through a rubber sleeve 35, and a hydraulic medium 34 is arranged between the metal core clamp 31 and the rubber sleeve 35. A first hydraulic pump 6 connected to the hydraulic medium 34 is also arranged on one side of the thermostatic box 36;

[0041] The gas collecting device 4 is connected to one end of the core sample 33 away from the pressurized gas injection device 2, and is used to receive the methane gas overflowed from the pressurized gas injection device 2, and convert the amount of the overflowed methane gas into liquid weight by the water displacement method;

[0042] The measuring device 5 is connected to the gas collecting device 4 and is used to measure the weight of the liquid discharged by the gas collecting device 4 .

[0043] In the embodiment of the present invention, the gas pipeline 12 is made of metal material.

[0044] like Figure 1As shown, as a preferred embodiment of the present invention, the pressurized gas injection device 2 includes a gas collecting metal tank 21, the top of the gas collecting metal tank 21 is connected to the methane gas tank 1, the top of the gas collecting metal tank 21 is also connected to one side of the core sample 33 through the gas pipeline 12, and a third ventilation valve F3 is also provided on the gas pipeline 12 between the gas collecting metal tank 21 and the high-pressure displacement device 3, the top of the gas collecting metal tank 21 is also connected to a vacuum pump 8 through the gas pipeline 12, and a second ventilation valve F2 is also provided on the gas pipeline 12 between the gas collecting metal tank 21 and the vacuum pump 8, a first metal piston 22 is provided in the gas collecting metal tank 21, hydraulic oil 23 is provided in the area below the first metal piston 22 in the gas collecting metal tank 21, and a second hydraulic pump 7 connected to the hydraulic oil 23 is also provided on one side of the gas collecting metal tank 21.

[0045] In the embodiment of the present invention, when in use, the second hydraulic pump 7 is pressure-set, pressurized, and depressurized, and the hydraulic oil is transmitted to the first metal piston 22, so that the air pressure in the gas collecting metal tank 21 can be adjusted. At the same time, the upper space of the gas collecting metal tank 21 can be evacuated by the vacuum pump 8.

[0046] like Figure 1 As shown, as a preferred embodiment of the present invention, the gas collecting device 4 includes a gas collecting bottle 41, and the gas collecting bottle 41 contains measuring water 42. The side of the core sample 33 away from the pressurized gas injection device 2 is connected to the top of the gas collecting bottle 41 through the gas transmission pipeline 12. The top of the gas collecting bottle 41 is also connected to the measuring device 5 through a drainage pipeline, and one end of the drainage pipeline is inserted into the measuring water 42.

[0047] An air pump 9 is also provided on one side of the gas collecting bottle 41 . The air pump 9 is connected to the gas collecting bottle 41 through a gas supply pipeline 12 , and a fourth ventilation valve F4 is also provided on the gas supply pipeline 12 .

[0048] In the embodiment of the present invention, the gas overflowing from the core sample 33 is transported to the gas collecting bottle 41 through the corresponding gas supply pipeline 12, so that the measuring water 42 is discharged to the measuring device 5 through the drainage pipeline. By measuring the weight of the discharged water, the corresponding volume can be calculated, and the volume of the overflowing gas can be measured.

[0049] like Figure 1 As shown, as a preferred embodiment of the present invention, the measuring device 5 includes a high-precision balance 53, a container containing measuring water 52 is placed on the high-precision balance 53, and the end of the drainage pipe away from the gas collecting device 4 is inserted into the measuring water 52, and a silicone oil layer 51 is also provided in the container to prevent the external environment from affecting the weight of the measuring water 52.

[0050] like Figure 1As shown, as a preferred embodiment of the present invention, it also includes a pressure control module 10, which is connected to the first hydraulic pump 6 and the second hydraulic pump 7 at the same time, and is used for electronic control of the first hydraulic pump 6 and the second hydraulic pump 7, such as pressure setting, pressurization and pressure relief.

[0051] like Figure 1 As shown, as a preferred embodiment of the present invention, it also includes a flow monitoring module 11, which is connected to the high-precision balance 53 and is used for electronic control of operations such as zeroing, detection, stopping and data export of the high-precision balance 53.

[0052] Another embodiment of the present invention provides a method for simulating and measuring the methane lateral storage capacity of a shale formation, based on the above-mentioned device for simulating and measuring the methane lateral storage capacity of a shale formation, comprising the following steps:

[0053] Step 1: Collect natural shale rock from the borehole and drill a cylindrical core sample 33 with a diameter of 2.5 cm along the horizontal lamina direction. The shale lamina direction is consistent with the long axis direction of the cylinder;

[0054] Step 2: Load the cylindrical core sample 33 into the high-pressure displacement device 3 and close all ventilation valves.

[0055] Step 3: Set the pressure of the first hydraulic pump 6 to the formation pressure condition (e.g. 50 MPa) through the pressure control module 10, start the first hydraulic pump 6, increase the confining pressure of the metal core clamp 31 to reach the formation pressure condition, and set the temperature of the thermostatic box 36 to the formation temperature (e.g. 80°C).

[0056] Step 4: Open the second vent valve F2 and the third vent valve F3, turn on the vacuum pump 8 to evacuate the gas collecting metal tank 21 and the upstream pipeline, stop the vacuum when the pressure reaches -0.1 MPa, and close all vent valves;

[0057] Step 5: Put a proper amount of water into the measuring device 5, and drip silicone oil to ensure that the water does not evaporate; open the fourth ventilation valve F4, turn on the air pump 9, let a proper amount of water flow back from the measuring device 5 into the gas collecting device 4, close the fourth ventilation valve F4 and the air pump 9, wait for the value of the high-precision balance 53 to stabilize, and control the value of the high-precision balance 53 to return to zero in the flow monitoring module 11;

[0058] Step 6: Open the first ventilation valve F1 to allow the gas in the methane gas tank 1 to fill the pressurized gas injection device 2, and then close the first ventilation valve F1;

[0059] Step 7: Open the third ventilation valve F3, set the pressure program of the second hydraulic pump 7 through the pressure control module 10 (for example, set 5MPa to maintain for 8h, 10MPa to maintain for 8h, and so on, until 30MPa), turn on the second hydraulic pump 7, and gradually increase the internal pressure of the boosting gas injection device 2 according to the set program;

[0060] Step 8: The flow monitoring module 11 records the changes of the high-precision balance 53 to analyze the gas sealing ability of the core sample 33 under a certain temperature and confining pressure.

[0061] As a preferred embodiment of the present invention, based on the above-mentioned device and method, a cylindrical core sample 33 with a diameter of 2.5 cm and a length of 3 cm is used, and saturated water treatment (water saturation Sw=100%) is performed. The specific operation steps are as follows:

[0062] 1) Put the cylindrical core sample 33 into the rubber sleeve 35, and put the rubber sleeve 35 containing the core sample 33 into the metal core holder 31, fix the core sample 33 by the second metal pistons 32 at both ends of the core sample 33, and close all ventilation valves at the same time.

[0063] 2) The pressure is set in the pressure control module 10, and the pressure of the first hydraulic pump 6 is set to the formation pressure condition of 50 MPa, and then the first hydraulic pump 6 is started to increase the confining pressure inside the metal core clamp 31 to reach the formation pressure condition. At the same time, the temperature of the thermostat 36 is set to the formation temperature of 60°C, and the temperature is waited for stabilization.

[0064] 3) Open the second ventilation valve F2 and the third ventilation valve F3, turn on the vacuum pump 8 to evacuate the upstream system of the core sample 33, stop the vacuum when the pressure reaches -0.1 MPa, and close all ventilation valves.

[0065] 4) 100 ml of water is placed in the measuring device 5, and silicone oil is dripped in to prevent the water from evaporating during the experiment. The fourth ventilation valve F4 is opened, and the air pump 9 is turned on. Due to the pressure reduction in the gas collecting bottle 41, 50 ml of water flows back from the measuring device 5 into the gas collecting device 4, and the amount of water is ensured to cover the drainage pipe. The fourth ventilation valve F4 and the air pump 9 are closed, and the value of the high-precision balance 53 is controlled to be stable in the flow detection module 11, indicating that the pressure in the gas collecting bottle 41 is balanced. The value of the high-precision balance 53 is controlled to return to zero.

[0066] 5) Open the first ventilation valve F1 to allow the methane in the methane gas tank 1 to enter the gas collecting metal tank 21, naturally pushing the first metal piston 22 to the bottom, and after the pressure is balanced, close the first ventilation valve F1.

[0067] 7) Open the third ventilation valve F3, and set the pressure program of the second hydraulic pump 7 through the pressure control module 10, specifically: set 5MPa for 12h, 8MPa for 12h, 11MPa for 12h, and so on with 3MPa as intervals until 29MPa, and then start the second hydraulic pump 7 to gradually increase the internal pressure of the boosting gas injection device 2 according to the set program;

[0068] 8) Start the flow monitoring module 11, which will record the value of the high-precision balance 53 and the pressure value of the second pressure pump 7 every 5 seconds.

[0069] 9) After waiting for the experiment process to end, the pressure control module 10 controls the components to stop, and then exports the time-pressure-flow data. The results are as follows: Figure 2 As shown, it is used to analyze the gas sealing ability of the core under a certain temperature and confining pressure.

[0070] 10) The flow rate under different methane injection pressures can be used to determine the pressure at which gas passes through shale (e.g. Figure 3 ), when the pressure reaches 14MPa, the flow rate is significantly increased. It can be considered that for the shale sample with Sw=100%, the sealing pressure is 14MPa. In addition, the flow rate can be calculated according to the time-flow relationship under different pressures to determine the seepage capacity of the sample.

[0071] 11) Replace samples with different water saturation (Sw = 75%, 50%, 25%, 0%) and repeat the above steps to compare the lateral sealing capacity of different samples for methane. Figure 4 As shown, when Sw=75%, the sealing ability is the strongest and methane never passes through the shale. When Sw=0% and 25%, the sealing ability is weak and methane passes through the sample at a faster speed at 5MPa.

[0072] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for simulating and measuring the lateral storage capacity of methane in a shale formation, characterized in that: It includes a methane gas tank, a pressurized gas injection device, a high-pressure displacement device, a gas collection device and a measuring device; The methane gas tank is connected to the pressurized gas injection device through a gas pipeline, and the gas pipeline between the methane gas tank and the pressurized gas injection device is also provided with a first vent valve, and the pressurized gas injection device is used to pressurize the gas delivered by the methane gas tank and deliver it to the high-pressure displacement device; The high-pressure displacement device comprises a thermostatic box, in which a metal core clamp for clamping the core sample along the axial direction of the core sample and a second metal piston for clamping the two ends of the core sample are arranged, the metal core clamp is in contact with the core sample through a rubber sleeve, and a hydraulic medium is arranged between the metal core clamp and the rubber sleeve, and a first hydraulic pump connected to the hydraulic medium is also arranged on one side of the thermostatic box; The gas collecting device is connected to one end of the core sample away from the pressurized gas injection device, and is used to receive the methane gas overflowed from the pressurized gas injection device, and convert the amount of the overflowed methane gas into liquid weight by a water displacement method; The measuring device is connected to the gas collecting device and is used to measure the weight of the liquid discharged by the gas collecting device.

2. The shale formation methane lateral storage capacity simulation measurement device according to claim 1, characterized in that: The pressurized gas injection device includes a gas collecting metal tank, the top of which is connected to a methane gas tank, the top of which is also connected to one side of a core sample via a gas pipeline, and a third ventilation valve is provided on the gas pipeline between the gas collecting metal tank and the high-pressure displacement device, the top of the gas collecting metal tank is also connected to a vacuum pump via a gas pipeline, and a second ventilation valve is provided on the gas pipeline between the gas collecting metal tank and the vacuum pump, a first metal piston is provided in the gas collecting metal tank, hydraulic oil is provided in an area below the first metal piston in the gas collecting metal tank, and a second hydraulic pump connected to the hydraulic oil is provided on one side of the gas collecting metal tank.

3. The device for simulating and measuring the methane lateral storage capacity of shale formations according to claim 2, characterized in that: The gas collecting device comprises a gas collecting bottle, in which measuring water is contained, a side of the core sample away from the pressurized gas injection device is connected to the top of the gas collecting bottle through a gas transmission pipeline, and the top of the gas collecting bottle is also connected to the measuring device through a drainage pipeline, and one end of the drainage pipeline is inserted into the measuring water; An air pump is also provided on one side of the gas collecting bottle. The air pump is connected to the gas collecting bottle through a gas supply pipeline, and a fourth ventilation valve is also provided on the gas supply pipeline.

4. The shale formation methane lateral storage capacity simulation measurement device according to claim 3, characterized in that: The measuring device comprises a high-precision balance, on which a container containing measuring water is placed, and one end of the drainage pipeline away from the gas collecting device is inserted into the measuring water, and a silicone oil layer is also arranged in the container.

5. The device for simulating and measuring the methane lateral storage capacity of shale formations according to claim 4, characterized in that: It also includes a pressure control module, which is connected to the first hydraulic pump and the second hydraulic pump at the same time and is used for electronically controlling the pressure setting, pressurization and pressure relief of the first hydraulic pump and the second hydraulic pump.

6. The shale formation methane lateral storage capacity simulation measurement device according to claim 5, characterized in that: It also includes a flow monitoring module, which is connected to the high-precision balance and is used for electronically controlling zeroing, detection, stopping and data export of the high-precision balance.

7. A method for simulating and measuring the methane lateral storage capacity of a shale formation, based on the device for simulating and measuring the methane lateral storage capacity of a shale formation according to claim 6, characterized in that: The following steps are involved: Step 1: Collect natural shale rock from the borehole and drill a cylindrical core sample along the horizontal lamina direction. The shale lamina direction is consistent with the long axis direction of the cylinder; Step 2: Load the cylindrical core sample into the high-pressure displacement device and close all ventilation valves; Step 3: Setting the pressure of the first hydraulic pump to the formation pressure condition through the pressure control module, starting the first hydraulic pump to increase the confining pressure of the metal core holder to the formation pressure condition, and setting the temperature of the thermostatic box to the formation temperature; Step 4: Open the second vent valve and the third vent valve, turn on the vacuum pump to evacuate the gas collecting metal tank and the upstream pipeline, stop the vacuum when the pressure reaches -0.1MPa, and close all vent valves; Step 5: Put a proper amount of water into the measuring device, and drip silicone oil to ensure that the water does not evaporate; open the fourth ventilation valve, turn on the air pump, let a proper amount of water flow back from the measuring device into the gas collecting device, close the fourth ventilation valve and the air pump, wait for the high-precision balance value to stabilize, and control the high-precision balance value to return to zero in the flow monitoring module; Step 6: Open the first vent valve to allow the gas in the methane gas tank to fill the pressurized gas injection device, and then close the first vent valve; Step 7: Open the third ventilation valve, set the pressure program of the second hydraulic pump through the pressure control module, turn on the second hydraulic pump, and gradually increase the internal pressure of the boosting and gas injection device according to the set program; Step 8: The flow monitoring module is used to record the changes of the high-precision balance to analyze the gas sealing ability of the core sample under a certain temperature and confining pressure.

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