An experimental analysis method for interwell permeability of unconventional reservoir pressure-channeling gas wells

Abstract

The invention relates to an inter-well permeability experimental analysis method for an unconventional reservoir pressure-channeling gas well, and belongs to the field of oil and gas field development. The method establishes a scientific inter-well permeability experimental analysis method for an unconventional reservoir pressure-channeling gas well, and the technical scheme is: based on an inter-well permeability experimental system for an unconventional reservoir pressure-channeling gas well, oil and gas field production data and standard experimental core geometric parameters are collected; equivalent experimental pressure difference and equivalent core sand addition amount are calculated; core fracture making experiment is carried out and permeability is tested after sand filling; inter-well permeability experiment of an unconventional reservoir pressure-channeling gas well is carried out to obtain experimental data; experimental data and mine pressure data are processed to draw a pressure response characteristic curve plate of the pressure-channeled well; an experimental pressure curve with the greatest correlation with an actual pressure curve of the pressure-channeled well is found, and the reservoir permeability between the fractured well and the pressure-channeled well is quickly obtained based on the experimental pressure curve; the invention has good practical application effect, reliable calculation results and strong scalability.

Description

Technical Field

[0001] The invention relates to an inter-well permeability experimental analysis method for an unconventional reservoir pressure-channeling gas well, and belongs to the field of oil and gas field development. Background Art

[0002] With the continuous development of oil and gas field development technology, hydraulic fracturing is used more and more widely. Large-scale hydraulic fracturing will form a large and complex fracture network, but excessive expansion of fractures may cause crosstalk between wells. When fracturing infill wells or wells with a small well spacing, it is easy to cause crosstalk with adjacent wells. Crosstalk refers to the connection between a well and an adjacent well during the fracturing process, which causes a sudden and substantial increase in the liquid production of the adjacent well, an increase in casing pressure, and a substantial decrease in gas production, which is harmful to the performance of the well. However, in order to increase the ultimate recoverable reserves, the well spacing will continue to shrink, and the crosstalk phenomenon will become more and more serious, directly affecting the production of old and new wells that are crosstalked. Therefore, convenient and quick evaluation of the interwell permeability of crosstalked gas wells in unconventional reservoirs is conducive to conducting relevant research on crosstalk between wells and verifying it with numerical simulation results. In field applications, it can quickly determine the type of communication medium between two crosstalked wells.

[0003] After extensive research, the patent number CN201410355691.7, "Experimental method for testing the permeability of reservoir cores before and after hydraulic fracturing under triaxial conditions", is based on a thermal-fluid-solid coupled multiphase fluid fracturing-seepage experimental system for reservoir permeability media, and can perform in-situ measurement of the permeability of reservoir permeability media before and after hydraulic fracturing under triaxial stress conditions; the patent number CN201310147687.7, "An experimental device and method for transforming shale gas reservoirs by pulse hydraulic fracturing", is based on an experimental device for transforming shale gas reservoirs by pulse hydraulic fracturing, and can simulate the operating environment of shale samples under certain confining pressure conditions under the hydraulic action of different main working parameters such as pulse pressure and pulse frequency, and test the changes in permeability before and after fracturing.

[0004] In general, there are many methods for evaluating reservoir core permeability at present, but all of them involve testing the reservoir core permeability before and after fracturing. There are few methods involving testing the reservoir permeability between two wells under the effect of inter-well pressure channeling. A reservoir core permeability testing method that takes into account the effect of pressure channeling, obtains the reservoir permeability between two wells, is needed, is easy to use, and has high accuracy. Summary of the invention

[0005] The purpose of the present invention is to establish a scientific inter-well permeability experimental analysis method for pressure-channeled gas wells in unconventional reservoirs. The present invention is based on an inter-well permeability experimental system for pressure-channeled gas wells in unconventional reservoirs, collects oil and gas field production data and standard experimental core geometric parameters; calculates equivalent experimental pressure difference and equivalent core sand addition amount; conducts core fracture experiment and tests permeability after sand filling; conducts inter-well permeability experiment for pressure-channeled gas wells in unconventional reservoirs to obtain experimental data; processes experimental data and mine pressure data, and draws a pressure response characteristic curve plate of the pressure-channeled well; finds out the experimental pressure curve with the greatest correlation with the actual pressure curve of the pressure-channeled well, and quickly obtains the reservoir permeability between the fracturing well and the pressure-channeled well based on this; the present invention has good practical application effect, reliable calculation results, and strong extensibility.

[0006] To achieve the above object, the present invention provides an interwell permeability test device for unconventional reservoir pressure-crossing gas wells, comprising:

[0007] The core simulation system comprises a core holder I, a core holder II, a core holder III and a confining pressure pump, wherein the core holder I, the core holder II and the core holder III have a cavity for placing the core, and the confining pressure pump is connected to the core holder I, the core holder II and the core holder III and is used to apply pressure to the periphery of the core holder I, the core holder II and the core holder III;

[0008] A fluid system, comprising an air injection pipeline I, an air injection pipeline II, an air injection pipeline III, a liquid injection pipeline and a discharge assembly, wherein the air injection pipeline I, the air injection pipeline II and the air injection pipeline III are respectively connected to the inlet ends of the core holder I, the core holder II and the core holder III through pressure regulating valves I, II and III, and the liquid injection pipeline is connected to the inlet end of the core holder I through a pressure regulating valve IV, and the air injection pipeline I, the air injection pipeline II, the air injection pipeline III and the liquid injection pipeline are used to sequentially inject air and fracturing fluid into the core, and when the pressure inside the core holder I, the core holder II and the core holder III is stable after the air is injected and the pressure is stable after the fracturing fluid is injected, the discharge assembly is used to discharge the air and fracturing fluid in the core;

[0009] A discharge component includes a pressure regulating valve V, a gas-liquid separator, a drying pipe and a mass flow controller. The pressure regulating valve V in the discharge component is used to control the outlet pressure of the core holder III to be constant. The gas-liquid separator in the discharge component is used to separate gas and fracturing fluid. The drying pipe in the discharge component is used to control the outlet gas to be dry. The mass flow controller in the discharge component is used to control the outlet flow to be constant. The pressure regulating valve V, the gas-liquid separator, the drying pipe and the mass flow controller in the discharge component are connected in sequence.

[0010] A data acquisition system is connected to the gas injection pipeline I, gas injection pipeline II, gas injection pipeline III, liquid injection pipeline and discharge assembly, and the data acquisition system is used to collect experimental data for drawing pressure response characteristic curve charts under different permeabilities.

[0011] To achieve the above object, the present invention also provides an experimental analysis method for the interwell permeability of an unconventional reservoir pressure-crossing gas well, the method comprising the following steps:

[0012] First, collect oil and gas field production data and standard experimental core geometry parameters, including reservoir pressure, bottom hole pressure, bottom hole construction pressure gradient, average fracture half length, average fracture height, average fracture width, bottom hole distance between two wells, density of added sand, total experimental core length, experimental core diameter and experimental core length;

[0013] Second, the experimental conditions for the interwell permeability experiment of the unconventional reservoir pressure-channeling gas well were designed based on the collected oil and gas field production data and standard experimental core geometry parameters;

[0014] Third, the experimental cores were fractured and then filled with sand and their permeability was measured;

[0015] Fourth, conduct interwell permeability experiments on unconventional reservoir pressure-induced gas wells;

[0016] Fifth, process the experimental data and mine pressure data and draw the pressure response characteristic curve of the pressurized well;

[0017] Sixth, by comparing the pressure response characteristic curve plates of the pressurized well, find the experimental pressure response characteristic curve with the greatest correlation with the actual pressure response characteristic curve of the pressurized well, and quickly obtain the reservoir permeability between the two wells.

[0018] In the above-mentioned unconventional reservoir pressure-channeling gas well interwell permeability experimental analysis method, the step of designing experimental conditions based on the collected oil and gas field production data and standard experimental core geometric parameters is:

[0019] First, according to the oil and gas field production data and experimental core data, the equivalent experimental pressure difference is calculated. The calculation formula is:

[0020] ;

[0021] In the formula, It is the pressure difference before the converted test pressure channeling, in MPa; is the length of the experimental core, in m; is the reservoir pressure, in MPa; is the bottom hole pressure, in MPa; is the distance from the bottom of the well, in m;

[0022] Second, according to the fracturing construction parameters, calculate the equivalent core sand addition amount, the calculation formula is:

[0023] ;

[0024] In the formula, For the i The equivalent amount of core sand added to the block core, in g; For the i Block experimental core, the unit is block; is the total number of experimental cores, in blocks; is the average crack height, in m; is the average crack width, in m; For the i The experimental core diameter of the block core, in m; For the i The experimental core length of the block core, in m; is the density of the added sand, in kg / m 3 ; is the average crack half-length, in m; is the distance between the bottoms of the two wells, in meters.

[0025] The above-mentioned unconventional reservoir pressure channeling gas well interwell permeability experimental analysis method, the said core fracture experiment is carried out on the experimental core, and then sand is filled and its permeability is measured. The specific steps are:

[0026] First, a core fracture experiment was conducted, sand was filled according to the equivalent core sand addition amount, and the permeability was measured. n Reservoir cores with different permeabilities;

[0027] Second, conduct core fracture experiment. i Pick n The maximum equivalent core sand addition amount is obtained, and sand is filled according to the maximum equivalent core sand addition amount of the core and the permeability is measured to obtain two fractured fracture cores with permeabilities equal to the average permeabilities of the fracture networks of the fracturing well and the fractured well.

[0028] The above-mentioned method for analyzing the interwell permeability of an unconventional reservoir pressure-channeled gas well comprises the following specific steps:

[0029] First, core holder I and core holder III simulate the fractured well and the well being fractured, and place the fractured core. Core holder II simulates the communication channel between the two wells. Place the cores in the order of the experiment. n Reservoir cores with different permeabilities;

[0030] Second, close valve V, open valves II, III, and IV, set the experimental temperature of core holders I, II, and III to the reservoir temperature according to the production data of the oil and gas field, set the confining pressure of core holders I, II, and III to the overlying formation pressure, and set the pressure regulating valve V so that the outlet pressure of core holder III is the bottom hole pressure of the well being pressurized;

[0031] Third, according to the reduced experimental pressure difference, the outlet pressure of the pressure regulating valve I is set so that the difference between the inlet pressure of the core holder I and the outlet pressure of the core holder III is equal to the reduced experimental pressure difference;

[0032] Fourth, close valve II, set the injection pressure of the fracturing fluid at the inlet of core holder I according to the bottom hole construction pressure gradient, so that the difference between the injection pressure of the fracturing fluid at the inlet of core holder I and the outlet pressure of core holder III is equal to the product of the bottom hole construction pressure gradient and the total experimental core length, open valve V after the pressure is stable, and measure the data of the outlet pressure of core holder III changing with time;

[0033] Fifth, the core in the core holder II is replaced with other reservoir cores with different permeabilities, and the experimental steps return to S401, and the experiment is repeated until all reservoir core experiments are completed.

[0034] The above-mentioned method for analyzing the interwell permeability of a gas well under pressure in an unconventional reservoir, wherein the experimental data and the field pressure data are processed and a pressure response characteristic curve of the gas well under pressure is drawn, has the following specific steps:

[0035] First, the bottom hole pressure of the experimental mine field is obtained by back-calculating the pressure response characteristic curve of the pressure-channeled well according to the experimental pressure difference. The calculation formula is:

[0036] ;

[0037] In the formula, is the bottom hole pressure of the experimental mine, in MPa; is the pressure of pressure sensor IV, in MPa; is the pressure of pressure sensor Ⅰ, in MPa; is the total experimental core length, in m; is the distance between the bottoms of the two wells, in meters;

[0038] Second, the experimental residence time is obtained by dividing the time series of experimental data by the total experimental core length, and the actual residence time is obtained by dividing the time series of the actual bottom hole pressure of the oil and gas field by the distance between the bottom holes of the two wells;

[0039] Third, draw a pressure response characteristic curve of the pressurized well.

[0040] Compared with the prior art, the present invention has the following beneficial effects: (1) combining theory with practice, the experimental pressure response characteristic curve of the pressure-converted well is more convenient and quick; (2) the test process is simple and easy to use; (3) it has strong scalability. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In the attached picture:

[0042] Figure 1 It is a method technology roadmap.

[0043] Figure 2 This is a diagram of the experimental setup.

[0044] Figure 3 It is a characteristic curve chart of the pressure response of the pressure-corrupted well.

[0045] Figure 2 Among them, 1-core simulation system, 11-core clamp Ⅰ, 12-core clamp Ⅱ, 13-core clamp Ⅲ, 14-confining pressure pump, 15-valve Ⅰ; 21-nitrogen bottle Ⅰ, 22-nitrogen bottle Ⅱ, 23-fracturing fluid tank, 24-pressure regulating valve Ⅰ, 25-pressure regulating valve Ⅱ, 26-pressure regulating valve Ⅲ, 27-pressure regulating valve Ⅳ, 28-valve Ⅱ, 29-valve Ⅲ, 210-valve Ⅳ, 211-valve Ⅴ , 212-gas injection pipeline I, 213-gas injection pipeline II, 214-gas injection pipeline III, 215-liquid injection pipeline; 3-discharge assembly, 31-pressure regulating valve V, 32-gas-liquid separator, 33-drying tube, 34-mass flow control meter; 4-data acquisition system, 41-pressure sensor I, 42-pressure sensor II, 43-pressure sensor III, 44-pressure sensor IV, 45-data processing terminal. DETAILED DESCRIPTION

[0046] The present invention is further described below in conjunction with the embodiments and drawings.

[0047] To achieve the above object, the present invention provides an interwell permeability test device for unconventional reservoir pressure-crossing gas wells, comprising:

[0048] The core simulation system comprises a core holder I, a core holder II, a core holder III and a confining pressure pump, wherein the core holder I, the core holder II and the core holder III have a cavity for placing the core, and the confining pressure pump is connected to the core holder I, the core holder II and the core holder III and is used to apply pressure to the periphery of the core holder I, the core holder II and the core holder III;

[0049] A fluid system, comprising an air injection pipeline I, an air injection pipeline II, an air injection pipeline III, a liquid injection pipeline and a discharge assembly, wherein the air injection pipeline I, the air injection pipeline II and the air injection pipeline III are respectively connected to the inlet ends of the core holder I, the core holder II and the core holder III through pressure regulating valves I, II and III, and the liquid injection pipeline is connected to the inlet end of the core holder I through a pressure regulating valve IV, and the air injection pipeline I, the air injection pipeline II, the air injection pipeline III and the liquid injection pipeline are used to sequentially inject air and fracturing fluid into the core, and when the pressure inside the core holder I, the core holder II and the core holder III is stable after the air is injected and the pressure is stable after the fracturing fluid is injected, the discharge assembly is used to discharge the air and fracturing fluid in the core;

[0050] A discharge component includes a pressure regulating valve V, a gas-liquid separator, a drying pipe and a mass flow controller. The pressure regulating valve V in the discharge component is used to control the outlet pressure of the core holder III to be constant. The gas-liquid separator in the discharge component is used to separate gas and fracturing fluid. The drying pipe in the discharge component is used to control the outlet gas to be dry. The mass flow controller in the discharge component is used to control the outlet flow to be constant. The pressure regulating valve V, the gas-liquid separator, the drying pipe and the mass flow controller in the discharge component are connected in sequence.

[0051] A data acquisition system is connected to the gas injection pipeline I, gas injection pipeline II, gas injection pipeline III, liquid injection pipeline and discharge assembly, and the data acquisition system is used to collect experimental data for drawing pressure response characteristic curve charts under different permeabilities.

[0052] The present invention also provides an experimental analysis method for the interwell permeability of an unconventional reservoir pressure-channeling gas well. Figure 1 The technical roadmap of this method includes the following steps:

[0053] First, collect oil and gas field production data and standard experimental core geometry parameters, including reservoir pressure, bottom hole pressure, bottom hole construction pressure gradient, average fracture half length, average fracture height, average fracture width, bottom hole distance between two wells, density of added sand, total experimental core length, experimental core diameter and experimental core length;

[0054] Second, the experimental conditions for the interwell permeability experiment of the unconventional reservoir pressure-channeling gas well were designed based on the collected oil and gas field production data and standard experimental core geometry parameters;

[0055] Third, the experimental cores were fractured and then filled with sand and their permeability was measured;

[0056] Fourth, conduct interwell permeability experiments on unconventional reservoir pressure-induced gas wells;

[0057] Fifth, process the experimental data and mine pressure data and draw the pressure response characteristic curve of the pressurized well;

[0058] Sixth, by comparing the pressure response characteristic curve plates of the pressurized well, find the experimental pressure response characteristic curve with the greatest correlation with the actual pressure response characteristic curve of the pressurized well, and quickly obtain the reservoir permeability between the two wells.

[0059] Furthermore, the steps of designing experimental conditions based on the collected oil and gas field production data and standard experimental core geometric parameters are:

[0060] First, according to the oil and gas field production data and experimental core data, the equivalent experimental pressure difference is calculated. The calculation formula is:

[0061] ;

[0062] In the formula, It is the converted experimental pressure difference, in MPa; is the total experimental core length, in m; is the reservoir pressure, in MPa; is the bottom hole pressure, in MPa; is the distance between the bottoms of the two wells, in meters;

[0063] Second, according to the fracturing construction parameters, calculate the equivalent core sand addition amount, the calculation formula is:

[0064] ;

[0065] In the formula, For the i The equivalent amount of core sand added to the block core, in g; For the i Block experimental core, the unit is block; is the total number of experimental cores, in blocks; is the average crack height, in m; is the average crack width, in m; For the i The experimental core diameter of the block core, in m; For the i The experimental core length of the block core, in m; is the density of the added sand, in kg / m 3 ; is the average crack half-length, in m; is the distance between the bottoms of the two wells, in meters.

[0066] Furthermore, the specific steps of performing the core fracture experiment on the experimental core, filling with sand and measuring its permeability are as follows:

[0067] First, a core fracture experiment was conducted, sand was filled according to the equivalent core sand addition amount, and the permeability was measured. n Reservoir cores with different permeabilities;

[0068] Second, conduct core fracture experiment. i Pick n The maximum equivalent core sand addition amount is obtained, and sand is filled according to the maximum equivalent core sand addition amount of the core and the permeability is measured to obtain two fractured fracture cores with permeabilities equal to the average permeabilities of the fracture networks of the fracturing well and the fractured well.

[0069] Furthermore, the interwell permeability experiment of the unconventional reservoir pressure-crossing gas wells is carried out in the following specific steps:

[0070] First, core holder I and core holder III simulate the fractured well and the well being fractured, and place the fractured core. Core holder II simulates the communication channel between the two wells. Place the cores in the order of the experiment. n Reservoir cores with different permeabilities;

[0071] Second, close valve V, open valves II, III, and IV, set the experimental temperature of core holders I, II, and III to the reservoir temperature according to the production data of the oil and gas field, set the confining pressure of core holders I, II, and III to the overlying formation pressure, and set the pressure regulating valve V so that the outlet pressure of core holder III is the bottom hole pressure of the well being pressurized;

[0072] Third, according to the reduced experimental pressure difference, the outlet pressure of the pressure regulating valve I is set so that the difference between the inlet pressure of the core holder I and the outlet pressure of the core holder III is equal to the reduced experimental pressure difference;

[0073] Fourth, close valve II, set the injection pressure of the fracturing fluid at the inlet of core holder I according to the bottom hole construction pressure gradient, so that the difference between the injection pressure of the fracturing fluid at the inlet of core holder I and the outlet pressure of core holder III is equal to the product of the bottom hole construction pressure gradient and the total experimental core length, open valve V after the pressure is stable, and measure the data of the outlet pressure of core holder III changing with time;

[0074] Fifth, the core in the core holder II is replaced with other reservoir cores with different permeabilities, and the experimental steps return to S401, and the experiment is repeated until all reservoir core experiments are completed.

[0075] Furthermore, the specific steps of processing the experimental data and the mine pressure data and drawing the pressure response characteristic curve of the pressure-channeled well are as follows:

[0076] First, the bottom hole pressure of the experimental mine field is obtained by back-calculating the pressure response characteristic curve of the pressure-channeled well according to the experimental pressure difference. The calculation formula is:

[0077] ;

[0078] In the formula, is the bottom hole pressure of the experimental mine, in MPa; is the pressure of real-time pressure sensor IV, in MPa; is the pressure of real-time pressure sensor I, in MPa; is the total experimental core length, in m; is the distance between the bottoms of the two wells, in meters;

[0079] Second, the experimental residence time is obtained by dividing the time series of experimental data by the total experimental core length, and the actual residence time is obtained by dividing the time series of the actual bottom hole pressure of the oil and gas field by the distance between the bottom holes of the two wells;

[0080] Third, draw a pressure response characteristic curve of the pressurized well.

[0081] Taking Well L220 as an example, this series of rock samples were used to conduct an experimental analysis of the interwell permeability of unconventional reservoir pressure-channeling gas wells. The reservoir pressure of the oil field is 80MPa, the bottom hole pressure is 10MPa, the distance between the bottom holes of the two wells is 300m, the total experimental core length is 0.15m, the average fracture height is 16m, the average fracture width is 0.01m, the average fracture half length is 120m, and the added sand density is 2.5kg / m 3 ,The experimental conditions design of the interwell permeability experiment of the unconventional reservoir pressure channeling gas well is shown in Table 1;

[0082] Table 1 Experimental conditions design for interwell permeability experiment of unconventional reservoir gas wells

[0083] ;

[0084] The core fracture experiment was conducted and the permeability was tested after sand filling, and 6 reservoir cores with different permeabilities and 2 fracture cores with permeabilities equal to the average permeability of the fracture network of the fractured well and the channeled well were obtained. The core permeabilities are shown in Table 2;

[0085] Table 2 Permeability of fracture cores and reservoir cores after fracturing

[0086]

[0087] Then the experiment was carried out, and standard experimental cores A-1, B-1 and C-1 were installed in the cavities of core holder I, core holder II and core holder III respectively. Valve V was closed, valves II, III and IV were opened, the experimental temperature was set to 85°C according to the reservoir temperature, the confining pressure was set to 80MPa according to the overlying formation pressure, the outlet pressure of core holder III was set to 20MPa according to the bottom hole pressure, the inlet pressure of core holder I was set to 20.035MPa according to the pressure difference before the equivalent experimental pressure channeling of 0.035MPa, valve II was closed, and the injection pressure of the fracturing fluid at the inlet of core holder I was set to 20.555MPa according to the bottom hole construction pressure gradient. After the pressure was stable, valve V was opened, and the data of the outlet pressure of core holder III changing with time were measured. Replace the core in the core holder II with the B-2 core, and repeat the above steps until the core in the core holder II is replaced with the B-6 core.

[0088] The experimental bottom hole pressure of the pressure-corrupted well is obtained by back-calculating the experimental pressure difference. The experimental retention time is obtained by dividing the time series of the experimental data by the total experimental core length. The actual retention time is obtained by dividing the time series of the actual bottom hole pressure of the oil and gas field by the distance between the bottom holes of the two wells. The pressure response characteristic curve of the pressure-corrupted well is drawn as shown in the figure. Figure 3 .

[0089] By comparing the pressure response characteristic curve of the well being pressurized, the experimental pressure response characteristic curve with the greatest correlation with the actual pressure response characteristic curve of the well being pressurized was found, and the reservoir permeability between the two wells was quickly obtained as: 32.8622mD.

[0090] Compared with the prior art, the present invention has the following beneficial effects: (1) combining theory with practice, the pressure response characteristic curve chart is more convenient and quick; (2) the test process is simple and easy to use; (3) it has strong scalability.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate rather than limit the technical solutions of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the present invention can still be modified or replaced by equivalents. Any modification or partial replacement that does not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. An experimental analysis method for interwell permeability of unconventional reservoir pressure-channeling gas wells, characterized in that: The experiment is conducted based on the interwell permeability experimental system of unconventional reservoir pressure-crossing gas wells, and the experimental system includes: A core simulation system (1) comprises a core holder I (11), a core holder II (12), a core holder III (13) and a confining pressure pump (14), wherein the core holder I (11), the core holder II (12) and the core holder III (13) have cavities for placing cores, and the confining pressure pump (14) is connected to the core holder I (11), the core holder II (12) and the core holder III (13) and is used to apply pressure to the peripheries of the core holder I (11), the core holder II (12) and the core holder III (13); A fluid system (2) comprises an air injection pipeline I (212), an air injection pipeline II (213), an air injection pipeline III (214), a liquid injection pipeline (215) and a discharge assembly (3), wherein the air injection pipeline I (212), the air injection pipeline II (213) and the air injection pipeline III (214) are respectively connected to the inlet ends of the core holder I (11), the core holder II (12) and the core holder III (13) through pressure regulating valves I (24), II (25) and III (26), and the liquid injection pipeline (21 5) connected to the inlet end of the core holder I (11) through a pressure regulating valve IV (27), the gas injection pipeline I (212), the gas injection pipeline II (213), the gas injection pipeline III (214) and the liquid injection pipeline (215) are used to sequentially inject gas and fracturing fluid into the core, and when the pressure inside the core holder I (11), the core holder II (12) and the core holder III (13) is stable after gas injection and after the pressure is stable after the fracturing fluid is injected, the discharge assembly (3) is used to discharge the gas and fracturing fluid in the core; A discharge assembly (3), comprising a pressure regulating valve V (31), a gas-liquid separator (32), a drying pipe (33) and a mass flow controller (34); the pressure regulating valve V (31) in the discharge assembly (3) is used to control the outlet pressure of the core holder III (13) to be constant; the gas-liquid separator (32) in the discharge assembly (3) is used to separate gas and fracturing fluid; the drying pipe (33) in the discharge assembly (3) is used to control the outlet gas to be dry; the mass flow controller (34) in the discharge assembly (3) is used to control the outlet flow to be constant; the pressure regulating valve V (31), the gas-liquid separator (32), the drying pipe (33) and the mass flow controller (34) in the discharge assembly (3) are connected in sequence; A data acquisition system (4) connected to the gas injection pipeline I (212), the gas injection pipeline II (213), the gas injection pipeline III (214), the liquid injection pipeline (215) and the discharge assembly (3), the data acquisition system being used to collect experimental data for drawing pressure response characteristic curves at different permeabilities; The method comprises the following steps: S100, collects oil and gas field production data and standard experimental core geometry parameters, including reservoir pressure, bottom hole pressure, bottom hole construction pressure gradient, average fracture half length, average fracture height, average fracture width, distance between two well bottom holes, density of added sand, total experimental core length, experimental core diameter and experimental core length; S200, based on the collected oil and gas field production data and standard experimental core geometry parameters, the experimental conditions for the interwell permeability experiment of the unconventional reservoir pressure channeling gas well are designed. The specific steps are as follows: S201, based on the oil and gas field production data and experimental core data, calculate the equivalent experimental pressure difference, the calculation formula is: ； In the formula, It is the converted experimental pressure difference, in MPa; is the total experimental core length, in m; is the reservoir pressure, in MPa; is the bottom hole pressure, in MPa; is the distance between the bottoms of the two wells, in meters; S202, according to the fracturing construction parameters, calculate the equivalent core sand addition amount, the calculation formula is: ； In the formula, For the i The equivalent amount of core sand added to the block core, in g; For the i Block experimental core, the unit is block; is the total number of experimental cores, in blocks; is the average crack height, in m; is the average crack width, in m; For the i The experimental core diameter of the block core, in m; For the i The experimental core length of the block core, in m; is the density of the added sand, in kg / m 3 ; is the average crack half-length, in m; is the distance between the bottoms of the two wells, in meters; S300, the core is fractured and then filled with sand and its permeability is measured. The specific steps are as follows: S301, conduct core fracture experiment, fill sand according to the equivalent core sand addition amount and measure the permeability, and obtain n Reservoir cores with different permeabilities; S302, conduct core fracture experiment, i Pick n The maximum equivalent core sand addition amount is obtained, and sand is filled according to the maximum equivalent core sand addition amount of the core and the permeability is measured to obtain two fractured fracture cores whose permeabilities are equal to the average permeabilities of the fracture networks of the fractured well and the channeled well; S400, conduct interwell permeability test of unconventional reservoir pressure-crossing gas wells, the specific steps are: S401, core holder I and core holder III simulate the fractured well and the well under pressure, and place the fractured core for fracturing. Core holder II simulates the communication channel between the two wells. Place them according to the experimental order. n Reservoir cores with different permeabilities; S402, close valve V, open valves II, III, and IV, set the experimental temperature of core holders I, II, and III to the reservoir temperature according to the production data of the oil and gas field, set the confining pressure of core holders I, II, and III to the overlying formation pressure, and set the pressure regulating valve V so that the outlet pressure of core holder III is the bottom hole pressure of the well being pressurized; S403, according to the reduced experimental pressure difference, setting the outlet pressure of the pressure regulating valve I so that the difference between the inlet pressure of the core holder I and the outlet pressure of the core holder III is equal to the reduced experimental pressure difference; S404, close valve II, set the injection pressure of the fracturing fluid at the inlet of the core holder I according to the bottom hole construction pressure gradient, so that the difference between the injection pressure of the fracturing fluid at the inlet of the core holder I and the outlet pressure of the core holder III is equal to the product of the bottom hole construction pressure gradient and the total experimental core length, open valve V after the pressure is stable, and measure the data of the outlet pressure of the core holder III changing with time; S405, replacing the core in the core holder II with other reservoir cores with different permeabilities, and the experimental steps return to S401, repeating the experiment until all the reservoir cores are tested; S500, processes the experimental data and the mine pressure data and draws a pressure response characteristic curve of the pressure-channeled well. The specific experimental steps are as follows: S501, the bottom hole pressure of the experimental mine field of the pressure response characteristic curve of the pressure-channeled well is obtained by back-calculation according to the experimental pressure difference, and the calculation formula is: ； In the formula, is the bottom hole pressure of the experimental mine, in MPa; is the pressure of pressure sensor IV, in MPa; is the pressure of pressure sensor Ⅰ, in MPa; is the total experimental core length, in m; is the distance between the bottoms of the two wells, in meters; S502, dividing the time series of experimental data by the total experimental core length to obtain the experimental residence time, and dividing the time series of the actual bottom hole pressure of the oil and gas field by the distance between the bottom holes of the two wells to obtain the actual residence time; S503, drawing a pressure response characteristic curve of the pressure-channeled well; S600, by comparing the pressure response characteristic curve of the well being pressurized, finds the experimental pressure response characteristic curve with the greatest correlation with the actual pressure response characteristic curve of the well being pressurized, and quickly obtains the reservoir permeability between the two wells.

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