An electric pulse fracturing and gas displacement integrated experimental system and method

Abstract

The application provides an electric pulse fracturing and gas displacement integrated experiment system and method, which comprises a running chamber, a water injection system, a gas injection system, a water outlet detection system, a gas extraction detection system and an electric pulse system, wherein all the inner wall surfaces of the running chamber are provided with the electric pulse system, the water outlet of the water injection system is communicated with the water inlet at the upper part of the running chamber, the water outlet at the lower part of the running chamber is communicated with the water inlet of the water outlet detection system, the gas outlet of the gas injection system is communicated with the gas inlet at the lower part of the running chamber, and the gas outlet at the upper part of the running chamber is communicated with the gas inlet of the gas extraction detection system; the application analyzes the gas extraction effect during the process of electric pulse fracturing and gas displacement by using laboratory means, simultaneously considers the influence of the actual formation pressure and hydrogeological conditions on the experiment process, makes the experiment simulation closer to the real geological conditions, and provides reliable experimental basis for the exploration and development of coalbed gas and gas treatment.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of coal measures gas resource exploration and development, and particularly relates to an electric pulse fracturing and gas displacement integrated experimental system and method. BACKGROUND

[0002] Coal measures gas is mainly composed of natural gas, and China is rich in coal measures gas resources and has great development potential. Coal measures gas reservoirs include coal reservoirs, sandstone reservoirs, carbonate rock reservoirs and shale reservoirs. Due to the characteristics of low porosity and low permeability, the exploration and development of coal measures gas is seriously restricted. At present, about 40% of coal measures gas in China needs to be imported from abroad. How to develop natural gas in such reservoirs is the focus and difficulty of current research.

[0003] China has a series of methods for the development of coal measures gas in low permeability reservoirs. According to the principle, it mainly includes fracturing and displacement. Reservoir fracturing methods include hydraulic permeability enhancement, reservoir acidification and resonance permeability enhancement. Displacement is mainly through the injection of nitrogen, carbon dioxide or flue gas to replace coal measures gas in the reservoir. At present, some teams have invented a laboratory device for a certain permeability enhancement method, but an experimental system integrating reservoir resonance and gas displacement has not been developed. SUMMARY

[0004] In order to solve the problems in the prior art, the present application provides an electric pulse fracturing and gas displacement integrated experimental system and method, which can provide experimental basis for coal bed gas exploration and development.

[0005] To achieve the above purpose, the present application provides the following technical scheme: an electric pulse fracturing and gas displacement integrated experimental system, comprising a running chamber, a water injection system, a gas injection system, a water outlet detection system, a gas extraction detection system and an electric pulse system, wherein all the inner walls of the running chamber are provided with the electric pulse system, the water outlet of the water injection system is communicated with the water inlet at the upper part of the running chamber, the water outlet at the lower part of the running chamber is communicated with the water inlet of the water outlet detection system, the gas outlet of the gas injection system is communicated with the gas inlet at the lower part of the running chamber, and the gas outlet at the upper part of the running chamber is communicated with the gas inlet of the gas extraction detection system.

[0006] Further, the running chamber comprises a rock sample chamber, an explosion chamber and a protection chamber which are sleeved together from inside to outside, the top of the rock sample chamber, the explosion chamber and the protection chamber is provided with an opening, the rock sample chamber is hollow inside for filling rock samples, a screw cap is arranged at the top opening of the rock sample chamber, a pressure sensor and a gas concentration sensor are arranged on the screw cap, and a check valve is arranged on the outer wall of the rock sample chamber; a detachable explosion chamber top is arranged at the top opening of the explosion chamber, a detachable protection chamber top is arranged at the top opening of the protection chamber, and the explosion chamber top and the protection chamber top are fixedly connected together, a pressure monitor and a gas concentration monitor are arranged on the protection chamber top; the inner wall of the explosion chamber is provided with the electric pulse system.

[0007] Further, the rock sample chamber wall is non-conductive and ultrasonic wave penetrable, and is made of organic glass containing silicate; the explosion cavity wall is non-conductive and explosion-proof, and is made of cement material with plastic insulation coating; the protection cavity wall can shield electromagnetic wave and is non-conductive, and uses high magnetic permeability material as a shielding layer.

[0008] Further, the electric pulse system comprises a metal wire, a carbon rod, a rubber rod, a capacitor and a field effect tube switch, the carbon rod is wound with the metal wire, the rubber rod is arranged through the center of the carbon rod, and the fixed end of the rubber rod is sequentially led out from the wall surfaces of the explosion cavity and the protection cavity and connected with the capacitor and the field effect tube switch to form a closed loop.

[0009] Further, the water injection system comprises a formation water storage tank, a high-pressure water pump and a flow meter, the water outlet of the formation water storage tank is connected with the water inlet of the high-pressure water pump through a water conveying pipe, and the water outlet of the high-pressure water pump is communicated with the water inlet at the upper part of the operation chamber through the flow meter.

[0010] Further, the water outlet detection system comprises a high-pressure water pump, a flow meter, a water storage tank and a water sample analyzer, the water outlet at the lower part of the operation chamber is communicated with the water inlet of the high-pressure water pump through a water conveying pipe, the water outlet of the high-pressure water pump is communicated with the water inlet of the water storage tank, and the water outlet of the water storage tank is connected with a drain valve and the water sample analyzer.

[0011] Further, the gas injection system comprises a gas storage tank and a gas suction pump, the gas outlet of the gas storage tank is communicated with the gas inlet at the lower part of the operation chamber through the gas suction pump, and the gas storage tank comprises a CO2 gas storage tank, an N2 gas storage tank and a CH4 gas storage tank.

[0012] Further, the gas suction system comprises a gas suction pump, a gas collection tank and a gas analyzer, the gas outlet at the upper part of the operation chamber is communicated with the inlet of the gas suction pump through a gas conveying pipe, the outlet of the gas suction pump is communicated with the inlet of the gas collection tank, a gas flow meter is arranged between the gas suction pump and the gas collection tank, and the gas outlet of the gas collection tank is connected with a gas outlet valve and the gas analyzer.

[0013] The application also provides an electric pulse induced cracking and gas displacement integrated experiment method, which is carried out by using the experiment system and comprises the following specific steps.

[0014] Step 1: placing a rock sample in the operation chamber, sealing the operation chamber and adding formation water prepared according to the ion content of a field measured formation water sample into the water injection system;

[0015] Step 2: opening the gas suction detection system, sucking out the gas in the operation chamber to keep the operation chamber in a vacuum state, and analyzing the components and content proportion of the sucked out gas;

[0016] Step 3, open the gas injection system, run the chamber into the same gas composition and content ratio as the gas obtained in step, close the gas injection system;

[0017] Step 4, open the water injection system to inject the formation water in the running chamber until the pressure in the running chamber is the measured formation pressure, and close the water injection system;

[0018] Step 5, open the electric pulse system, the electric pulse system radiates electric pulse shock wave, at this time, open the gas injection system to inject gas into the running chamber, open the gas extraction detection system to extract the gas in the running chamber, and obtain the variation curve of the gas extraction amount with time;

[0019] Step 6, perform a control experiment, adjust the intensity and radiation direction of the electric pulse shock wave of the electric pulse system, and the injection rate of the gas injection system, and obtain the optimal method of electric pulse fracturing and gas displacement.

[0020] Further, the size of the rock sample is 20cm-50cm in diameter and 10cm-50cm in height.

[0021] Compared with the prior art, the present application has at least the following beneficial effects:

[0022] The present application provides an electric pulse fracturing and gas displacement integrated experimental system, which realizes the analysis of the gas extraction effect during the process of electric pulse fracturing and gas displacement by means of laboratory means through reasonable layout of the running chamber, the water injection system, the gas injection system, the water detection system, the gas extraction detection system and the electric pulse system, and the experimental system of the present application is used for experimental simulation of solid rock samples, and the influence of the actual formation pressure and the hydrogeological condition on the experimental process is considered, so that the experimental simulation is closer to the real geological condition, and reliable experimental basis is provided for the exploration and development of coal measures gas and gas control; the experimental system of the present application is installed in modules, and each part is relatively independent, so that the operation is simpler in terms of updating and maintenance. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is the front view (including internal structure) of the electric pulse fracturing and gas displacement integrated experimental device.

[0024] Figure 2 is the left view (including internal structure) of the electric pulse fracturing and gas displacement integrated experimental device.

[0025] Figure 3 is the top view (including internal structure) of the electric pulse fracturing and gas displacement integrated experimental device.

[0026] Figure 4 is the flowchart of the present application.

[0027] In the attached diagram: 1. Operating chamber; 2. Water injection system; 3. Air injection system; 4. Water outlet detection system; 5. Air extraction detection system; 30. Electrical pulse system; 6. Operating chamber base; 7. Rock sample chamber; 8. Explosion chamber; 9. Protective chamber; 10. Rock sample; 11. Check valve; 12. Top screw cap; 13. Pressure sensor; 14. Buckle; 15. Metal wire; 16. Carbon rod; 17. Rubber rod; 18. Positioning pin; 19. Capacitor; 20. Field-effect transistor switch; 21. Nut; 22. Pressure monitor. 2; Gas concentration monitor; 23; Formation water storage tank; 24; Water supply pipe; 25; High-pressure water pump; 26; Flow meter; 27; Air pump; 28; Gas supply pipe; 29; CO2 storage tank; 31; N2 storage tank; 32; CH4 storage tank; 33; Gas flow meter; 34; Water storage tank; 35; Drain valve; 36; Water sample analyzer; 37; Gas collection box; 38; Gas outlet valve; 39; Gas analyzer; 40; Airbag; 41; Gas concentration sensor; 42; Fixing plate; 43. Detailed Implementation

[0028] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0029] like Figures 1-3 As shown, this invention provides an integrated experimental system for electro-pulse fracturing and gas displacement, comprising an operating chamber 1 for fracturing and gas displacement, an electro-pulse system 30 for generating electro-pulse stimulation, a water injection system 2 for simulating real formation water, a gas injection system 3 for inducing gas displacement, a water discharge detection system 4 for detecting changes in formation water after the experiment, and a gas extraction detection system 5 for detecting changes in gas after the experiment. The electro-pulse system 30 is installed on all walls of the operating chamber 1. The outlet of the water injection system 2 is connected to the inlet at the top of the operating chamber 1, the outlet at the bottom of the operating chamber 1 is connected to the inlet of the water discharge detection system 4, the outlet of the gas injection system 3 is connected to the inlet at the bottom of the operating chamber 1, and the outlet at the top of the operating chamber 1 is connected to the inlet of the gas extraction detection system 5, preventing water and gas from overflowing.

[0030] The operating chamber 1 consists of a rock sample chamber 7, an explosion chamber 8, and a protective chamber 9, arranged from the inside out. The rock sample chamber 7, the explosion chamber 8, and the protective chamber 9 are fixed together by a fixing plate 43.

[0031] The rock sample chamber 7 has an opening at the top and is hollow inside for filling with rock samples. A screw cap 12 is installed at the top opening, and a pressure sensor 13 and a gas concentration sensor 42 are installed on the screw cap 12. The pressure sensor 13 is used to provide real-time feedback on the rock sample pressure, and the gas concentration sensor 42 is used to monitor the carbon dioxide and methane concentrations, making the pressure and gas concentration in the rock sample chamber 7 visible and ensuring that the pressure and gas concentration in the rock sample chamber 7 reach the target values. Four check valves 11 are evenly installed on the outer wall of the rock sample chamber 7. When the pressure in the rock sample chamber 7 reaches the maximum pressure of the coal reservoir, the check valves automatically open to ensure that the pressure in the rock sample chamber 7 is maintained within the range of reservoir pressure fluctuations in the actual formation.

[0032] The top of the explosion chamber 8 is open and the interior is hollow for placing the rock sample chamber 7. A detachable explosion chamber top is provided at the top opening of the explosion chamber 8, and the explosion chamber top is connected to the body of the explosion chamber 8 by a buckle 14.

[0033] The electrical pulse system 30 is connected to the inner wall of the explosion chamber 8. The electrical pulse system 30 includes a carbon rod 16 wound with metal wire 15. A rubber rod 17 is provided through the center of the carbon rod 16. The fixed end of the rubber rod 17 passes through the wall of the explosion chamber 8 and is fixed to the wall of the protective chamber 9 by a positioning pin 18. The metal wire 15 forms a closed loop with the outside through the hollow rubber rod 17. The closed loop includes a capacitor 19 and a field-effect transistor switch 20.

[0034] The top of the protective chamber 9 is open and hollow inside to house the explosion chamber 8. The top of the protective chamber 9 is detachably connected to the top of the protective chamber via a buckle 14. A pressure monitor 22 and a gas concentration monitor 23 are installed on the top of the protective chamber to monitor the pressure and gas concentration in the protective chamber 9, preventing excessive pressure caused by gas / carbon dioxide leakage and resulting in danger. An air outlet is provided on the side wall of the top of the protective chamber, which is connected to the air bag 41 via an air outlet valve 39. When the gas / carbon dioxide concentration in the protective chamber is too high, the gas is released into the air bag 41. The air bag 41 can measure the volume of the released gas and ensure the safety of equipment, environment and personnel. The top of the explosion chamber and the top of the protective chamber are connected and fixed by four nuts 21.

[0035] The water injection system 2 includes a formation water storage tank 24, a high-pressure water pump 26, and a flow meter 27. The outlet of the formation water storage tank 24 is connected to the inlet of the high-pressure water pump 26 through a water supply pipe 25, and the outlet of the high-pressure water pump 26 is connected to the inlet of the rock sample chamber 7 through the flow meter 27.

[0036] The water effluent detection system 4 includes a high-pressure water pump 26, a flow meter 27, a water storage tank 35, and a water sample analyzer 37. The outlet of the rock sample chamber 7 is connected to the inlet of the high-pressure water pump 26 through a water supply pipe 25. The outlet of the high-pressure water pump 26 is connected to the inlet of the water storage tank 35. A drain valve 36 is installed on the outlet of the water storage tank 35. The outlet of the water storage tank 35 is also connected to the water sample analyzer 37.

[0037] The gas injection system 3 includes a gas storage tank and a vacuum pump 28. The gas outlet of the gas storage tank is connected to the gas inlet of the rock sample chamber 7 through the vacuum pump 28. The gas storage tank includes a CO2 gas storage tank 31, an N2 gas storage tank 32 and a CH4 gas storage tank 33.

[0038] The gas extraction system 5 includes a gas extraction pump 28, a gas collection box 38, and a gas analyzer 40. The gas outlet of the rock sample chamber 7 is connected to the inlet of the gas extraction pump 28 through a gas extraction pipe. The outlet of the gas extraction pump 28 is connected to the inlet of the gas collection box 38. A gas flow meter 34 is installed between the gas extraction pump 28 and the gas collection box 38. An outlet valve 39 and a gas analyzer 40 are connected to the gas outlet of the gas collection box 38.

[0039] Sealing adhesive is installed at the connection points between the rock sample chamber 7 and the water injection system 2, the gas injection system 3, the water effluent detection system 4, and the air extraction system 5 to prevent water and gas from overflowing.

[0040] Preferably, the walls of the rock sample chamber 7 are non-conductive and can be penetrated by ultrasonic waves, and are made of silicate-containing plexiglass;

[0041] Preferably, the walls of the explosion chamber 8 are non-conductive and explosion-proof, and are made of cement material with a plastic insulating coating;

[0042] Preferably, the wall of the protective cavity 9 can shield electromagnetic waves and is non-conductive, and a high magnetic permeability material is used as the shielding layer;

[0043] Preferably, the check valve 11 can withstand a pressure range between 1.6-16MPa, and the valve opening pressure is set according to the measured formation pressure.

[0044] Preferably, the pressure sensor 13 has a measurement range of 0-10 MPa, is explosion-proof, and is resistant to high temperatures;

[0045] Preferably, the diameter of the metal wire 15 is between 0.1-0.4mm, with 0.2mm recommended. Copper, aluminum wire, or any other material with high resistance can be selected.

[0046] Preferably, the diameter of carbon rod 16 is between 1 and 5 cm, and its length is basically the same as the height of rock sample 10;

[0047] Preferably, the pressure of the high-pressure water pump 26 is between 2-11 kg, and the flow rate is between 4-20 L / min;

[0048] Preferably, the rated pumping capacity of the air pump 28 is between 20-100m³. 3 Between / h, the ultimate vacuum is -0.098MPa (-735mmHg);

[0049] Preferably, the CO2 storage tank 31, N2 storage tank 32, and CH4 storage tank 33 have a capacity between 10-15L.

[0050] Preferably, the airbag 41 can hold a gas volume between 5-20L and is made of latex material;

[0051] Preferably, the fixing plate 43 is made of cement fiberboard.

[0052] Preferably, the water pipe 25 and the gas pipe 29 are sealed with sealant at the contact points with the rock sample chamber to prevent water and gas from overflowing.

[0053] Reference Figure 4 The operation of the integrated experimental device for electrical pulse fracturing and gas displacement can be further divided into the following steps:

[0054] Step 1: Prepare and place rock samples and formation water.

[0055] A sample group is defined as a set of strata within a range of 2-10 square meters, with 4 or more samples per group. The collected rock samples are processed into cylindrical shapes and placed in sample chamber 7. Rock sample 10 has the same specifications as the sample chamber, with a diameter between 20-50 cm and a height between 10-50 cm. The screw cap on the top of sample chamber 7 is tightened. Simultaneously, formation water is prepared based on the ion content of the field-measured formation water samples and poured into formation water storage tank 24.

[0056] Step 2: Perform scanning electron microscopy on the samples before the experiment.

[0057] From the remaining fragments during the rock sample processing, rock samples with fresh and relatively flat cross sections were selected for scanning electron microscopy experiments to observe and photograph the pore and fracture morphology and distribution characteristics of the rock samples before the electrical pulse fracturing and gas displacement experiments.

[0058] Step 3: Vacuum the rock sample chamber 7 and analyze the gas component content.

[0059] The gas flow meter 34, gas collection box 38, gas analyzer 40, and high-pressure pump 28 in the gas extraction and detection system 5 are turned on in sequence, while the exhaust valve 39 remains closed. Gas from the rock sample chamber 7 is drawn into the gas collection box 38, maintaining a vacuum in the rock sample chamber. Simultaneously, the gas analyzer 40 analyzes the gas components and content to obtain results. Finally, the gas flow meter 34, gas collection box 38, and gas analyzer 40 are turned off in sequence, and the exhaust valve 39 is opened to release the waste gas, restoring the gas collection box to a gas-free vacuum state.

[0060] Step 4: Inject relevant gases and formation water to simulate real conditions.

[0061] Based on the gas composition and content detected in step 3, firstly, turn on the gas flow meter 34, CO2 storage tank 32, N2 storage tank 33, CH4 storage tank 34, and vacuum pump 28 in the gas injection system 3 in sequence to introduce gas with a proportion equivalent to the actual gas content, and then turn off all instruments in the gas injection system 3. Then, turn on the flow meter, formation water storage tank 24, and high-pressure water pump 26 in the water injection system 2 in sequence to inject formation water into the rock sample chamber 7. After the pressure sensor 13 is monitored in real time until the actual formation pressure is reached, turn off all switches in the water injection system 2.

[0062] Step 5: Run the fracturing and displacement experiments;

[0063] The field-effect transistor switch 20 can adjust the current magnitude and emit an electric pulse shock wave through the metal wire 15 wound on the carbon rod 16. At the same time, the gas flow meter 34, CO2 storage tank 31, N2 storage tank 32, CH4 storage tank 33 and the extraction pump 28 in the gas injection system 3 are turned on in sequence to stably inject carbon dioxide / nitrogen into the rock sample chamber 7. At the same time, the extraction detection system 5 is turned on to extract the gas in the rock sample chamber according to the empirical extraction rate, and obtain the curve of gas extraction amount changing with time. This helps to determine the optimal time range for gas extraction and the time range with the maximum gas extraction rate, which helps to guide on-site gas extraction.

[0064] A comparative experiment was conducted, setting different electrical pulse intensities, radiation directions, and carbon dioxide / nitrogen injection rates to simulate the gas extraction process. The replacement efficiency under different parameter combinations was analyzed, and the optimal combination method of electrical pulse fracturing and carbon dioxide / nitrogen displacement was determined, so as to maximize the gas extraction volume at a lower cost.

[0065] Step 6, treat residual gas and water

[0066] Once the gas content stops changing, shut down all devices in the gas injection system 3. Then, sequentially open the gas flow meter 34, the extraction pump 28, and the gas collection box 38 in the extraction detection system 5. When the methane and carbon dioxide concentrations measured by the gas concentration sensor 42 meet the standards, shut down all devices in the extraction detection system 5. Simultaneously, sequentially open the flow meter 27, the water storage tank 35, the water sample analyzer 37, and the high-pressure water pump 26 in the water extraction detection system 4. After the water sample analyzer 37 analyzes the ionic composition and content in the water, the remaining wastewater is discharged through the drain valve 36. Finally, shut down all devices in the water extraction detection system 4.

[0067] Step 7: Perform scanning electron microscopy on the samples after the experiment.

[0068] Open the top buckle 14 of the protective chamber 9, disassemble the top of the protective chamber and the top of the explosion chamber, unscrew the screw cap 12 on the top of the rock sample chamber 7, take out the broken rock sample for scanning electron microscopy, observe and photograph the pore and fracture morphology and distribution characteristics of the rock sample after the electrical pulse fracturing and gas displacement experiments; the pore and fracture morphology, quantity and distribution characteristics essentially reflect the fracturing and displacement effects, further confirming the accuracy of the optimal combination method in step 5, and helping to further improve the theoretical research on the degree of influence of fracturing and displacement on reservoir stimulation.

[0069] Step 8: Inspect and clean the experimental setup.

[0070] Check the apparatus for damage and clean and organize the experimental equipment.

[0071] This invention overcomes the current inability to simulate the integrated effect of electrical pulse fracturing and gas displacement in the laboratory. It allows for the analysis of gas extraction efficiency during the simultaneous occurrence of electrical pulse fracturing and gas displacement using laboratory methods. The invention simulates experiments using solid rock samples rather than fractured rock samples, while also considering the influence of actual formation pressure and hydrogeological conditions on the experimental process. This makes the simulation closer to real geological conditions, providing reliable experimental data for coalbed methane exploration, development, and gas control. Furthermore, the experimental system of this invention is modularly installed, with each part relatively independent, making upgrades, replacements, and maintenance simpler.

[0072] The above description is merely a specific embodiment of the present invention and should not be construed as limiting the scope of the invention. Therefore, any substitution of equivalent components or equivalent changes and modifications made within the scope of protection of the present invention should still fall within the scope of the present invention.

Claims

1. An integrated experimental system for electrical pulse fracturing and gas displacement, characterized in that, It includes an operating chamber (1), a water injection system (2), an air injection system (3), a water outlet detection system (4), an air extraction detection system (5), and an electric pulse system (30). The operating chamber (1) is equipped with an electric pulse system (30) on all the walls inside. The water outlet of the water injection system (2) is connected to the water inlet at the top of the operating chamber (1). The water outlet at the bottom of the operating chamber (1) is connected to the water inlet of the water outlet detection system (4). The air outlet of the air injection system (3) is connected to the air inlet at the bottom of the operating chamber (1). The air outlet at the top of the operating chamber (1) is connected to the air inlet of the air extraction detection system (5). The operating chamber (1) includes a rock sample chamber (7), an explosion chamber (8), and a protective chamber (9) that are fixed together from the inside to the outside. The top of the rock sample chamber (7), the explosion chamber (8), and the protective chamber (9) are all provided with openings. The interior of the rock sample chamber (7) is hollow and used to fill rock samples. A screw cap (12) is provided at the top opening. A pressure sensor (13) and a gas concentration sensor (42) are provided on the screw cap (12). Check valves (11) are provided on the side walls of the rock sample chamber (7). A detachable explosion chamber top is provided at the top opening of the explosion chamber (8). A detachable protective chamber top is provided at the top opening of the protective chamber (9). The explosion chamber top and the protective chamber top are fixedly connected together. A pressure monitor (22) and a gas concentration monitor (23) are provided on the protective chamber top. An electrical pulse system (30) is provided on the inner wall of the explosion chamber (8).

2. The integrated experimental system for electrical pulse fracturing and gas displacement according to claim 1, characterized in that, The rock sample chamber (7) has a non-conductive wall that allows ultrasonic waves to penetrate it, and is made of plexiglass containing silicates; the explosion chamber (8) has a non-conductive wall that is explosion-proof, and is made of cement material with a plastic insulating coating; the protective chamber (9) has a wall that can shield electromagnetic waves and is non-conductive, and is made of a high magnetic permeability material as a shielding layer.

3. The integrated experimental system for electrical pulse fracturing and gas displacement according to claim 1, characterized in that, The electrical pulse system (30) includes a metal wire (15), a carbon rod (16), a rubber rod (17), a capacitor (19), and a field-effect transistor switch (20). The carbon rod (16) is wrapped with a metal wire (15), and a rubber rod (17) is provided through the center of the carbon rod (16). The fixed end of the rubber rod (17) passes through the walls of the explosion cavity (8) and the protection cavity (9) in sequence and is connected to the capacitor (19) and the field-effect transistor switch (20) to form a closed loop.

4. The integrated experimental system for electrical pulse fracturing and gas displacement according to claim 1, characterized in that, The water injection system (2) includes a formation water storage tank (24), a high-pressure water pump (26), and a flow meter (27). The outlet of the formation water storage tank (24) is connected to the inlet of the high-pressure water pump (26) through a water supply pipe (25), and the outlet of the high-pressure water pump (26) is connected to the inlet of the upper part of the operating room (1) through the flow meter (27).

5. The integrated experimental system for electrical pulse fracturing and gas displacement according to claim 1, characterized in that, The water outlet detection system (4) includes a high-pressure water pump (26), a flow meter (27), a water storage tank (35), and a water sample analyzer (37). The outlet of the lower part of the operating room (1) is connected to the inlet of the high-pressure water pump (26) through a water supply pipe (25). The outlet of the high-pressure water pump (26) is connected to the inlet of the water storage tank (35). The outlet of the water storage tank (35) is connected to a drain valve (36) and a water sample analyzer (37).

6. The integrated experimental system for electrical pulse fracturing and gas displacement according to claim 1, characterized in that, The gas injection system (3) includes a gas storage tank and a vacuum pump (28). The gas outlet of the gas storage tank is connected to the air inlet at the bottom of the operating room (1) through the vacuum pump (28). The gas storage tank includes a CO2 gas storage tank (31), an N2 gas storage tank (32), and a CH4 gas storage tank (33).

7. The integrated experimental system for electrical pulse fracturing and gas displacement according to claim 1, characterized in that, The air extraction detection system (5) includes an air extraction pump (28), a gas collection box (38), and a gas analyzer (40). The air outlet at the top of the operating room (1) is connected to the inlet of the air extraction pump (28) through a gas supply pipe (29). The outlet of the air extraction pump (28) is connected to the inlet of the gas collection box (38). A gas flow meter (34) is installed between the air extraction pump (28) and the gas collection box (38). An air outlet valve (39) and a gas analyzer (40) are connected to the air outlet of the gas collection box (38).

8. An integrated experimental method for electrical pulse fracturing and gas displacement, characterized in that, The experimental system according to any one of claims 1-7 is used, and the specific steps are as follows: Step 1: Place the rock sample in the operating chamber (1), seal the operating chamber (1), and add formation water prepared according to the ion content of the field measured formation water sample into the water injection system (2); Step 2: Turn on the gas extraction detection system (5) to extract the gas in the operating chamber (1) to keep the operating chamber (1) in a vacuum state, and analyze the composition and content ratio of the extracted gas. Step 3: Open the gas injection system (3), introduce gas with the same gas composition and content ratio as obtained in Step 2 into the operating chamber (1), and close the gas injection system (3). Step 4: Open the water injection system (2) and inject the formation water into the operating room (1) until the pressure in the operating room (1) is the measured formation pressure, then close the water injection system (2). Step 5, turn on the electric pulse system (30), the electric pulse system (30) emits electric pulse shock wave, at this time turn on the gas injection system (3) to inject gas into the operating room (1), turn on the gas extraction detection system (5) to extract the gas in the operating room (1), and obtain the curve of gas extraction amount changing with time; Step 6: Conduct a control experiment, adjust the intensity and radiation direction of the electric pulse wave of the electric pulse system (30), and the gas injection rate of the gas injection system (3), and obtain the optimal method of electric pulse fracturing and gas displacement.

9. The integrated experimental method for electrical pulse fracturing and gas displacement according to claim 8, characterized in that, The rock sample (10) has a diameter of 20cm-50cm and a height of 10cm-50cm.

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