Shale spontaneous imbibition evaluation device and method

Abstract

The present invention provides a shale spontaneous imbibition evaluation device and method, belonging to the technical field of shale development. The evaluation device of the present invention comprises a cutting area, a drying area, a saturation area, a glue coating area, an imbibition area and a computer control system; according to the experimental requirements, the computer control system controls the cutting, drying, saturation and gluing of samples in the cutting area, the drying area, the saturation area, the glue coating area and the imbibition area, and the entire experimental process can be completed on one device, reducing the errors in the sample transfer and processing process, increasing the sample utilization rate, and improving the accuracy and comparability of the experiment.

Description

Technical Field

[0001] The present invention relates to the technical field of shale development, and in particular to a shale spontaneous imbibition evaluation device and method. Background Art

[0002] Shale oil and gas mainly exist in the micro-nanoscale pores in organic matter and inorganic minerals in an adsorbed state. Therefore, the connectivity of the pore structure of shale reservoirs plays a vital role in the effective production of shale oil and gas. Spontaneous imbibition can evaluate the permeability of shale reservoirs and analyze the pore structure and pore connectivity of reservoirs. In addition, spontaneous imbibition can optimize the development plan of shale oil and gas, including the layout of horizontal wells, optimization of fracturing processes, and adjustment of production operations, thereby improving development efficiency and production benefits.

[0003] At present, there have been many research and developments on spontaneous imbibition equipment, but it often requires multiple instruments to work together to complete spontaneous imbibition experiments, including sample cutting, glue coating, imbibition, and mechanical property testing, which is not only time-consuming and labor-intensive, but also difficult to ensure the timeliness of each link. In addition, the current spontaneous imbibition analysis of pore connectivity requires multiple samples to complete, but due to the difficulty in sampling shale samples and their strong heterogeneity, the cost of spontaneous imbibition experiments is increased and the comparability of the experiments is reduced. In addition, spontaneous imbibition is of great significance to the evaluation and development of shale oil and gas reservoirs, such as the impact of imbibition water on reservoir strength during the well sealing process. However, the current spontaneous imbibition device has a relatively single function, which limits the in-depth understanding and application of complex imbibition phenomena. As recorded in the "Spontaneous Imbibition Experiment and Wettability Study of Shale Reservoirs", when conducting spontaneous imbibition experiments, the samples are locked on the spontaneous imbibition experiment instrument, and the samples are heated by a heating device to make their temperature reach the preset value. Solutions of different concentrations are added according to the experimental plan, and the time, concentration and temperature after the start of the experiment are measured. The shale reservoir is pressure tested using a high-pressure measurement system to observe its osmotic pressure and wettability performance. The crude oil adsorption experiment is carried out through an oil saturation device to observe the effects of various solutions on the shale reservoir. In the experiment, suitable samples need to be prepared, and the samples need to be cut, dried, saturated, and coated with glue. It can be seen that the spontaneous imbibition experiment process requires multiple independent steps and multiple devices to complete sample preparation and testing. At the same time, multiple samples are required to complete the spontaneous imbibition experiment. The samples need to be transferred and processed multiple times, which is not only time-consuming but also prone to errors. Summary of the invention

[0004] In response to the problems of the prior art, the present invention provides a shale spontaneous imbibition evaluation device, which integrates multiple experimental devices such as cutting, drying, saturation, gluing, and imbibition, and can carry out multifunctional spontaneous imbibition experiments on the same sample, thereby reducing errors in sample transfer and processing, increasing sample utilization, and improving the accuracy and comparability of the experiment.

[0005] The present invention provides a shale spontaneous imbibition evaluation device, comprising a cutting area, a drying area, a saturation area, a glue coating area, an imbibition area and a computer control system; the cutting area, the drying area, the glue coating area and the imbibition area are arranged in sequence, and the saturation area is adjacent to the drying area;

[0006] The cutting area is provided with a first opening and closing door and a second opening and closing door, a cutting assembly and a transport assembly; the transport assembly is capable of moving the sample; the computer control system is connected to both the transport assembly and the cutting assembly;

[0007] The drying area is connected to the cutting area via a second opening and closing door; the drying area is provided with a first transport channel, a drying component and a fourth opening and closing door; the drying component is provided below the first transport channel, and the drying component and the first transport channel are both connected to the computer control system;

[0008] The gluing area is provided with a second transport channel, a positioning device, a three-axis moving assembly, a gluing assembly, a third opening and closing door, and a sixth opening and closing door. The positioning device is connected to the three-axis moving assembly, and the positioning device is arranged on the gluing assembly; the positioning device and the three-axis moving assembly are both connected to the computer control system; the drying area is connected to the gluing area through the third opening and closing door, the second transport channel can move the sample from the third opening and closing door to the gluing assembly, and the sixth opening and closing door is arranged below the second transport channel;

[0009] The infiltration zone is provided with a fifth opening and closing door and an infiltration experimental device, and the transport component can move the sample from the glue coating zone to the infiltration zone through the fifth opening and closing door;

[0010] The saturation zone is provided with a seventh opening and closing door, and the saturation zone is provided with a container, and the container is used to contain water.

[0011] Preferably, the transport assembly comprises a telescopic arm and an automatic control clamp, and both the telescopic arm and the automatic control clamp are connected to the computer control system.

[0012] Preferably, a weight sensor is provided on the telescopic arm.

[0013] Preferably, the cutting area is further provided with a solenoid valve, one end of which is connected to a gas supply source, and the other end of which is connected to the cutting assembly, for controlling the cutting accuracy and speed.

[0014] Preferably, the cutting assembly comprises a laser cutting machine and a loading platform, and the laser cutting machine is connected to the computer control system.

[0015] Preferably, a waste collection area is arranged below the loading platform, and a waste collector is also arranged on the side of the loading platform.

[0016] Preferably, the drying component includes a heater, a first temperature sensor, a humidity controller and an air pump, the heater, the humidity controller and the air pump are all connected to the computer control system, the heater is arranged below the first transport channel, the first temperature sensor is connected to the first transport channel, and the heater is connected to the humidity controller.

[0017] Preferably, the glue coating component includes a glue coating mold, a mobile operating platform and a glue transfer component, the glue transfer component includes a glue tank, a glue pump, a glue storage tank, a glue guide hose, a glue cylinder, a pressing sheet and a glue hose connected in sequence, a piston is arranged in the glue storage tank, the mobile operating platform is arranged below the glue hose, and the glue coating mold is arranged on the mobile operating platform.

[0018] Preferably, a first liquid level sensor and a pressure detector are also provided on the glue storage tank.

[0019] Preferably, a safety valve is also provided above the glue storage tank.

[0020] Preferably, the glue storage tank is also connected to a first solution feeder.

[0021] Preferably, there are two glue tanks, the glue pump is connected to one of the glue tanks, a mixing mixer is arranged between the two glue tanks, both glue tanks are connected to the inlet of the mixing mixer, one end of the first solution feeder is connected to the outlet of the mixing mixer, and the other end of the first solution feeder is connected to the glue storage tank.

[0022] Preferably, the positioning device comprises a position sensor and a directional control valve, and the directional control valve is connected to the three-axis moving assembly.

[0023] Preferably, the three-axis moving assembly comprises an X-axis moving axis, a Y-axis moving axis and a Z-axis moving axis, the X-axis moving axis, the Y-axis moving axis and the Z-axis moving axis are perpendicular to each other, and the glue coating mold can move along the three-axis moving assembly.

[0024] Preferably, the glue coating mold is a hexahedron, and the interior of each face is filled with a heating plate. The interior of the glue coating mold is a cavity, and a first glue injection port, a second glue injection port, a third glue injection port and a fourth glue injection port are provided on the upper wall, the bottom wall and two opposite side walls. The first glue injection port, the second glue injection port, the third glue injection port and the fourth glue injection port are respectively connected to a glue hose, and a first control axis, a second control axis, a third control axis and a fourth control axis are respectively provided at the first glue injection port, the second glue injection port, the third glue injection port and the fourth glue injection port.

[0025] Preferably, the imbibition experimental device comprises a spontaneous imbibition heat preservation and moisture sealed system, which comprises a shell and a flexible connecting rod, a sample rotating clamp, a thermostat, a humidifier, a first analytical balance, a second analytical balance, an imbibition dish, a second liquid level sensor, an acoustic energy converter, a sample cabinet, a second temperature sensor and a humidity sensor arranged inside the shell; the humidity sensor and the second temperature sensor are arranged on the side wall of the shell, and the flexible connecting rod, the sample rotating clamp, the thermostat, the humidifier, the first analytical balance, the second analytical balance, the imbibition dish, the second liquid level sensor, the acoustic energy converter and the sample cabinet are all arranged inside the shell;

[0026] The first analytical balance is connected to the sample cabinet via a flexible connecting rod, the sample rotating clamp and the acoustic energy converter are arranged inside the sample cabinet, a sample clamp is also arranged inside the sample cabinet, the humidifier and the thermostat are arranged at the bottom or side wall of the housing, the second analytical balance is arranged at the bottom of the housing, the filtration dish is arranged above the second analytical balance, and a second liquid level sensor is arranged inside the filtration dish;

[0027] The infiltration and absorption dish is also connected to a water replenishment tank and an oil replenishment tank. The water replenishment tank is connected to the infiltration and absorption dish through a second solution feeder, and the oil replenishment tank is connected to the infiltration and absorption dish through a third solution feeder.

[0028] The present invention also provides a shale spontaneous imbibition evaluation method, using the shale spontaneous imbibition evaluation device, comprising the following steps:

[0029] Prepare samples by imbibition along the bedding;

[0030] Carry out layer-by-layer imbibition;

[0031] Preparation of translaminar imbibition samples;

[0032] Conduct translayer infiltration;

[0033] Preparation of samples with different saturation levels;

[0034] The samples with different saturations were subjected to bedding imbibition and trans-bedding imbibition. The data after bedding imbibition and trans-bedding imbibition were processed to obtain the imbibition index and mechanical parameters under different imbibition paths.

[0035] Preferably, the process of preparing the sample by layer imbibition includes:

[0036] Measure sample weight and dimensions;

[0037] The samples are dried in the drying area and glued in the glue coating area in turn;

[0038] Ultrasonic velocity measurement was performed on the samples after glue coating to obtain the initial mechanical parameters of the samples before the in-layer imbibition experiment was carried out.

[0039] Preferably, the layer imbibition process includes:

[0040] Measure the parameters of the bedding imbibition samples;

[0041] Conduct bedding imbibition on bedding imbibition samples in the imbibition zone;

[0042] Measure transverse and longitudinal wave velocities as well as weight changes before and after imbibition.

[0043] Preferably, the translaminar imbibition sample preparation process comprises:

[0044] The samples are dried in the drying area and glued in the glue coating area in turn;

[0045] Laser cutting is performed on the glue-coated samples according to the set layer penetration sample index;

[0046] Ultrasonic velocity measurement was performed on the cut samples to obtain the initial mechanical parameters of the samples before the penetration experiment was carried out.

[0047] Preferably, the layer penetration process includes:

[0048] Carry out parameter measurement of the through-layer imbibition samples;

[0049] Conducting trans-layer imbibition on the trans-layer imbibition samples in the imbibition area;

[0050] Measure transverse and longitudinal wave velocities as well as weight changes before and after imbibition.

[0051] Preferably, the process of preparing samples with different saturations includes:

[0052] Different samples are dried in the drying area and glued in the glue coating area in turn;

[0053] Laser cutting is performed on different samples after glue coating according to the set different saturation sample indicators;

[0054] Soaking the cut different samples in the saturation zone according to the set different saturation sample indexes to obtain samples with different saturations;

[0055] Ultrasonic velocity measurements were performed on samples with different saturations to obtain the mechanical parameters of samples with different saturations before conducting the in-bedding imbibition and through-bedding imbibition experiments.

[0056] Preferably, samples with different saturations are subjected to layer-wise imbibition and layer-through imbibition, and data processing after layer-wise imbibition and layer-through imbibition is performed to obtain imbibition indexes and mechanical parameters under different imbibition paths, specifically including:

[0057] The samples with different saturation were imbibed along the layer in the imbibition zone, and the transverse and longitudinal wave velocities as well as the weight changes before and after the imbibition were measured.

[0058] The samples with different saturation were imbibed through the layers in the imbibition zone, and the transverse and longitudinal wave velocities as well as the weight changes before and after the imbibition were measured.

[0059] After data processing of in-beam imbibition and through-beam imbibition, the imbibition index and mechanical parameters under different imbibition paths were obtained.

[0060] Compared with the prior art, the present invention has at least the following beneficial effects:

[0061] (1) Samples with known shale components can be precisely cut by a laser cutting machine. The samples can be transferred between different areas inside the device by opening and closing doors, telescopic suspension arms, and a mobile stage. The cut samples are transferred to the drying area by the telescopic suspension arm. After drying, they are moved to the glue coating area by the mobile stage to complete the glue coating process. The glue-coated samples can be used to complete the measurement of the imbibition parameters and mechanical parameters in the imbibition area.

[0062] (2) The glue coating mold is controlled by a computer, the glue coating thickness is controllable, and the glue coating surface is uniform, avoiding under-coating or over-coating caused by manual glue coating, and reducing the error caused by the pretreatment process to the spontaneous infiltration experiment.

[0063] (3) The samples used in the experiment are the same, which avoids the influence of factors such as sample density, porosity, and size on the spontaneous imbibition experiment. In addition, the difference in fluid migration in different directions can be evaluated by the anisotropic imbibition index, saving a certain amount of cost for shale oil extraction.

[0064] (4) The same sample can be used to evaluate the effect of water infiltration along and through the layers on the compressive strength of the sample, and then analyze the mechanical weakening effect of water on the sample in different directions, providing technical guidance for the design of horizontal wells.

[0065] (5) The water content of the sample is automatically controlled by a computer, which avoids the influence of human factors on the experiment. Moreover, through the imbibition index under different initial water content conditions, the effect of the initial water content on the spontaneous imbibition of the reservoir can be clearly observed, providing certain guidance for reservoir exploitation and development. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 A schematic diagram of a shale spontaneous imbibition evaluation experimental device according to an embodiment of the present invention.

[0067] Figure 2 It is a three-dimensional schematic diagram of the imbibition zone of an embodiment of the present invention.

[0068] Figure 3 It is a schematic front view of the imbibition zone of one embodiment of the present invention.

[0069] Figure 4 It is a left schematic view of the imbibition zone of one embodiment of the present invention.

[0070] Figure 5 It is a schematic top view of the imbibition zone of one embodiment of the present invention.

[0071] Figure 6 The figure is a longitudinal cross-sectional view of a glue coating mold according to an embodiment of the present invention.

[0072] Figure 7 This is a technical roadmap of a shale spontaneous imbibition evaluation method according to an embodiment of the present invention. In the same experiment, some steps can be considered to be completed in one process, so no arrows are drawn in the figure, for example: parameter measurements include transverse and longitudinal wave velocities and weight changes.

[0073] In the figure, 1-first opening and closing door, 2-second opening and closing door, 3-third opening and closing door, 4-fourth opening and closing door, 5-fifth opening and closing door, 6-sixth opening and closing door, 7-seventh opening and closing door, 8-laser cutting machine, 9-carrying platform, 10-telescopic arm, 11-automatic control clamp, 12-first transportation channel, 13-second transportation channel, 14-heater, 15-first temperature sensor, 16-computer control system, 17-directional control valve, 18-rubber guide hose, 19-pressure detector, 20-safety valve, 21-glue storage tank, 22-first liquid level sensor, 23-piston, 24-glue pump, 25-first solution feeder, 26-glue cylinder, 27-glue tank, 28-mixing mixer, 29-tablet press, 30-hose, 31-mobile operating platform, 32-Z direction motion axis, 33-Y direction motion axis, 34 -positioning device, 35-thermostat, 36-humidifier, 37-second solution feeder, 38-third solution feeder, 39-humidity sensor, 40-second temperature sensor, 41-water supply tank, 42-oil supply tank, 43-infiltration dish, 44-second liquid level sensor; 45-solenoid valve, 46-weight sensor, 47-first analytical balance, 48-second analytical balance, 49-acoustic energy converter, 50-flexible connecting rod, 51-sample cabinet, 52-sample rotating clamp, 53-shell, 54-heating plate, 55-first glue injection port, 56-second glue injection port, 57-third glue injection port, 58-fourth glue injection port, 59-first control axis, 60-second control axis, 61-third control axis, 62-fourth control axis, 63-waste collector, 64-gas supply source, 65-sample, 66-support rod. DETAILED DESCRIPTION

[0074] The specific implementation modes of the present invention are described in detail below.

[0075] The present invention provides a shale spontaneous imbibition evaluation device, comprising a cutting area, a drying area, a saturation area, a glue coating area, an imbibition area and a computer control system 16; the cutting area, the drying area, the glue coating area and the imbibition area are arranged in sequence, and the saturation area is adjacent to the drying area;

[0076] The cutting area is provided with a first opening and closing door 1 and a second opening and closing door 2, a cutting assembly and a transport assembly; the transport assembly is capable of moving the sample 65; the computer control system 16 is connected to both the transport assembly and the cutting assembly;

[0077] The drying area is connected to the cutting area through a second opening and closing door 2; the drying area is provided with a first transport channel 12, a drying component and a fourth opening and closing door 4; the drying component is arranged below the first transport channel 12, and the drying component and the first transport channel 12 are both connected to the computer control system 16;

[0078] The gluing area is provided with a second transport channel 13, a positioning device 34, a three-axis moving assembly, a gluing assembly, a third opening and closing door 3 and a sixth opening and closing door 6, the positioning device 34 is connected to the three-axis moving assembly, and the positioning device 34 is arranged on the gluing assembly; the positioning device 34 and the three-axis moving assembly are both connected to the computer control system 16; the drying area is connected to the gluing area through the third opening and closing door 3, the second transport channel 13 can move the sample 65 from the third opening and closing door 3 to the gluing assembly, and the sixth opening and closing door 6 is arranged below the second transport channel 13;

[0079] The infiltration zone is provided with a fifth opening and closing door 5 and an infiltration experiment device, and the transport component can move the sample 65 from the glue coating zone to the infiltration zone through the fifth opening and closing door 5;

[0080] The saturation zone is provided with a seventh opening and closing door 7, and the saturation zone is provided with a container, and the container is used to contain water.

[0081] According to a specific embodiment of the present invention, the transport assembly includes a telescopic arm 10 and an automatic control clamp 11 , and both the telescopic arm 10 and the automatic control clamp 11 are connected to the computer control system 16 .

[0082] According to a specific embodiment of the present invention, a weight sensor 46 is provided on the telescopic arm 10 .

[0083] According to a specific embodiment of the present invention, the cutting area is further provided with a solenoid valve 45, one end of which is connected to the gas supply source 64, and the other end of which is connected to the cutting assembly, for controlling the cutting accuracy and speed. The solenoid valve 45 is used to control the flow of the fluid, and the precise control of the flow of the fluid is achieved by quickly opening or closing. When cutting the glue on the surface of the shale sample 65, it is very important to ensure the cutting quality. The solenoid valve 45 is used to accurately control the supply of the auxiliary gas, and the cutting quality and cutting speed may be improved by purging the auxiliary gas.

[0084] According to a specific embodiment of the present invention, the cutting assembly includes a laser cutting machine 8 and a loading platform 9 , and the laser cutting machine 8 is connected to the computer control system 16 .

[0085] According to a specific embodiment of the present invention, a waste collection area is arranged below the loading platform 9 , and a waste collector 63 is also arranged on the side of the loading platform 9 .

[0086] According to a specific embodiment of the present invention, the drying component includes a heater 14, a first temperature sensor 15, a humidity controller and an air pump, the heater 14, the humidity controller (not shown in the figure) and the air pump (not shown in the figure) are all connected to the computer control system 16, the heater 14 is arranged below the first transport channel 12, the first temperature sensor 15 is connected to the first transport channel 12, and the heater 14 is connected to the humidity controller. The function of the air pump is to extract moisture from the air to ensure that the sample 65 can be dried in a dry environment. When the sample 65 needs to be dried, the air pump will start to remove moisture from the air to ensure that the air in the drying area is dry.

[0087] According to a specific embodiment of the present invention, the glue coating component includes a glue coating mold, a mobile operating platform 31 and a glue transmission component, and the glue transmission component includes a glue tank 27, a glue pump 24, a glue storage tank 21, a glue guide tube 18, a glue cylinder 26, a pressing sheet 29 and a rubber hose 30 connected in sequence, a piston 23 is arranged in the glue storage tank 21, the mobile operating platform 31 is arranged below the rubber hose 30, and the glue coating mold is arranged on the mobile operating platform 31.

[0088] According to a specific embodiment of the present invention, a first liquid level sensor 22 and a pressure detector 19 are further provided on the glue storage tank 21 .

[0089] According to a specific embodiment of the present invention, a safety valve 20 is further provided above the glue storage tank 21. When the pressure detected by the pressure detector 19 exceeds the preset safety threshold, the safety valve 20 automatically opens to release the excess pressure and reduce the pressure in the glue coating area; when the pressure in the system drops to a safe range, the safety valve 20 automatically closes and the system returns to normal working state.

[0090] According to a specific embodiment of the present invention, the glue storage tank 21 is further connected to a first solution replenisher 25. The first liquid level sensor 22 is used to monitor the amount of glue in the glue storage tank 21. When the amount of glue is lower than the set minimum liquid level, the first liquid level sensor 22 sends a signal to the computer control system 16; after receiving the signal, the computer control system 16 starts the first solution replenisher 25 to replenish glue in the glue storage tank 21 until the preset liquid level is reached; when the amount of glue in the glue storage tank 21 reaches the set maximum liquid level, the first liquid level sensor 22 sends a signal to the computer control system 16 again, and the computer control system 16 controls the first solution replenisher 25 to stop working.

[0091] According to a specific embodiment of the present invention, there are two glue tanks 27, the glue pump 24 is connected to one of the glue tanks 27, a mixer 28 is arranged between the two glue tanks 27, both glue tanks 27 are connected to the inlet of the mixer 28, one end of the first solution replenisher 25 is connected to the outlet of the mixer 28, and the other end of the first solution replenisher 25 is connected to the glue storage tank 21. The first solution replenisher 25 is connected to the mixer 28 to replenish glue from the glue tank 27.

[0092] To improve the performance of the glue, the two glue tanks 27 can contain different glues (such as A glue and B glue), and the glue mixed in the two glue tanks 27 by the mixing mixer 28 can be used; the mixed glue is injected into the glue storage tank 21 through the first solution feeder 25 to ensure that there is enough glue for the subsequent gluing process.

[0093] According to a specific embodiment of the present invention, the positioning device 34 includes a position sensor (not shown in the figure) and a directional control valve 17, and the directional control valve 17 is connected to the three-axis moving assembly.

[0094] According to a specific embodiment of the present invention, the three-axis moving assembly includes an X-direction moving axis (not shown in the figure), a Y-direction moving axis 33 and a Z-direction moving axis 32, and the X-direction moving axis, the Y-direction moving axis 33 and the Z-direction moving axis 32 are perpendicular to each other.

[0095] According to a specific embodiment of the present invention, the glue coating mold is a hexahedron, and the interior of each face is filled with a heating plate 54. The interior of the glue coating mold is a cavity, and a first glue injection port 55, a second glue injection port 56, a third glue injection port 57 and a fourth glue injection port 58 are provided on the upper wall, the bottom wall and the two opposite side walls. The first glue injection port 55, the second glue injection port 56, the third glue injection port 57 and the fourth glue injection port 58 are respectively connected to a glue hose 30, and a first control axis 59, a second control axis 60, a third control axis 61 and a fourth control axis 62 are respectively provided at the first glue injection port 55, the second glue injection port 56, the third glue injection port 57 and the fourth glue injection port 58, so that the thickness of the glue coating can be controlled, that is, the thickness and uniformity of the glue coating are controllable.

[0096] According to a specific embodiment of the present invention, the glue-coating mold is made of a transparent material (such as PP plastic) that is not easily adhered by glues such as epoxy resin.

[0097] According to a specific embodiment of the present invention, the first glue injection port 55, the second glue injection port 56, the third glue injection port 57 and the fourth glue injection port 58 can be opened simultaneously or separately.

[0098] According to a specific embodiment of the present invention, the infiltration experimental device includes a spontaneous infiltration heat preservation and moisture closed system, which includes a shell and a soft connecting rod 50, a sample rotating clamp 52, a thermostat 35, a humidifier 36, a first analytical balance 47, a second analytical balance 48, an infiltration dish 43, a second liquid level sensor 44, an acoustic energy converter 49, a sample cabinet 51, a second temperature sensor 40 and a humidity sensor 39 arranged inside the shell; the humidity sensor 39 and the second temperature sensor 40 are arranged on the side wall of the shell, and the soft connecting rod 50, the sample rotating clamp 52, the thermostat 35, the humidifier 36, the first analytical balance 47, the second analytical balance 48, the infiltration dish 43, the second liquid level sensor 44, the acoustic energy converter 49 and the sample cabinet 51 are all arranged inside the shell;

[0099] The first analytical balance 47 is connected to the sample cabinet 51 through a flexible connecting rod 50, the sample rotating clamp 52 and the acoustic energy converter 49 are arranged inside the sample cabinet 51, and a sample clamp (not shown in the figure) is also arranged inside the sample cabinet 51, the humidifier 36 and the thermostat 35 are arranged at the bottom or side wall of the housing, the second analytical balance 48 is arranged at the bottom of the housing, the filtration dish 43 is arranged above the second analytical balance 48, and a second liquid level sensor 44 is arranged in the filtration dish 43;

[0100] The infiltration dish 43 is also connected to a water replenishment tank 41 and an oil replenishment tank 42 . The water replenishment tank 41 is connected to the infiltration dish 43 via a second solution feeder 37 , and the oil replenishment tank 42 is connected to the infiltration dish 43 via a third solution feeder 38 .

[0101] According to a specific embodiment of the present invention, a support rod 66 is further disposed below the first analytical balance 47 .

[0102] The present invention also provides a shale spontaneous imbibition evaluation method, using the shale spontaneous imbibition evaluation device, comprising the following steps:

[0103] Prepare samples by imbibition along the bedding;

[0104] Carry out layer-by-layer imbibition;

[0105] Preparation of translaminar imbibition samples;

[0106] Conduct translayer infiltration;

[0107] Preparation of samples with different saturation levels;

[0108] The samples with different saturations were subjected to bedding imbibition and trans-bedding imbibition. The data after bedding imbibition and trans-bedding imbibition were processed to obtain the imbibition index and mechanical parameters under different imbibition paths.

[0109] According to a specific embodiment of the present invention, the process of preparing the layer imbibition sample includes:

[0110] Measure sample weight and dimensions;

[0111] The samples are dried in the drying area and glued in the glue coating area in turn;

[0112] Ultrasonic velocity measurement was performed on the samples after glue coating to obtain the mechanical parameters of the samples before the layer imbibition experiment was carried out.

[0113] According to a specific embodiment of the present invention, the layer imbibition process comprises:

[0114] Measure the parameters of the bedding imbibition samples;

[0115] Conduct bedding imbibition on bedding imbibition samples in the imbibition zone;

[0116] Measure transverse and longitudinal wave velocities as well as weight changes before and after imbibition.

[0117] According to a specific embodiment of the present invention, the process of preparing the translaminar imbibition sample comprises:

[0118] The samples are dried in the drying area and glued in the glue coating area in turn;

[0119] Laser cutting is performed on the glue-coated samples according to the set layer penetration sample index;

[0120] Ultrasonic velocity measurement was performed on the cut samples to obtain the mechanical parameters of the samples before the penetration experiment was carried out.

[0121] According to a specific embodiment of the present invention, the layer penetration process includes:

[0122] Carry out parameter measurement of the through-layer imbibition samples;

[0123] Conducting trans-layer imbibition on the trans-layer imbibition samples in the imbibition area;

[0124] Measure transverse and longitudinal wave velocities as well as weight changes before and after imbibition.

[0125] According to a specific embodiment of the present invention, the process of preparing samples with different saturations includes:

[0126] Different samples are dried in the drying area and glued in the glue coating area in turn;

[0127] Laser cutting is performed on different samples after glue coating according to the set sample indexes of different saturation levels;

[0128] Soaking the cut different samples in the saturation zone according to the set different saturation sample indexes to obtain samples with different saturations;

[0129] Ultrasonic velocity measurements were performed on samples with different saturations to obtain the mechanical parameters of samples with different saturations before conducting the in-bedding imbibition and through-bedding imbibition experiments.

[0130] According to a specific embodiment of the present invention, samples with different saturations are subjected to layer-wise imbibition and layer-through imbibition, and data processing after layer-wise imbibition and layer-through imbibition is performed to obtain imbibition indexes and mechanical parameters under different imbibition paths, specifically including:

[0131] The samples with different saturation were imbibed along the layer in the imbibition zone, and the transverse and longitudinal wave velocities as well as the weight changes before and after the imbibition were measured.

[0132] The samples with different saturation were imbibed through the layers in the imbibition zone, and the transverse and longitudinal wave velocities as well as the weight changes before and after the imbibition were measured.

[0133] After data processing of in-beam imbibition and through-beam imbibition, the imbibition index and mechanical parameters under different imbibition paths were obtained.

[0134] Ultrasonic velocity measurement was performed on samples with different saturations after preparation, including drying, gluing, laser cutting, and preparation. Then, in-layer and through-layer imbibition experiments were carried out.

[0135] The process of performing the imbibition experiment is described in detail below according to an embodiment of the present invention:

[0136] (1) Experimental setup for different imbibition directions of the same sample

[0137] First, carry out the spontaneous water absorption experiment along the layer:

[0138] Cutting: open the first opening and closing door, place the sample 65 of known shale composition on the loading platform 9, close the first opening and closing door 1, control the movement of the telescopic arm 10 through the computer control system 16, and control the automatic control clamp 11 at the front end of the telescopic arm 10 to clamp the sample 65, move it to the laser cutting machine 8, set the cutting position and size (3cm×3cm×3cm), and after the cutting is completed, clamp it out with the telescopic arm 10.

[0139] Drying: Open the second door 2, open the fourth door 4, and let the automatic control clamp 11 at the front end of the telescopic arm 10 clamp the sample 65 through the first transport channel 12 to enter the drying area. Close the second door 2 and the fourth door 4, adjust the temperature to 60°C, and continue drying for more than 48 hours. The fourth door 4 is used to connect the cutting area and the drying area. After the cutting of the sample 65 is completed, the second door 2 is opened, and the telescopic arm 10 carries the sample 65 into the first transport channel 12; after closing the second door 2, open the fourth door 4 until the sample 65 completely enters the drying and saturation area, and then close the fourth door 4 to maintain the environmental conditions of the drying and saturation area.

[0140] Gluing: The third opening and closing door 3 is opened by the computer control system 16, and the sixth opening and closing door 6 is opened. The sample 65 is clamped by the automatic control clamp 11 at the front end of the telescopic arm 10 through the second transport channel 13 to enter the glue coating area, and the sample 65 is placed on the mobile operating platform 31, and then the third opening and closing door 3 and the sixth opening and closing door 6 are closed. The sixth opening and closing door 6 is used to connect the drying area and the glue coating area. When the sample 65 is dried, the third opening and closing door 3 is opened by the computer control system 16, and the telescopic arm 10 carries the sample 65 into the second transport channel 13; after closing the third opening and closing door 3, the sixth opening and closing door 6 is opened until the sample 65 completely enters the glue coating area, and then the sixth opening and closing door 6 is closed to maintain the environmental conditions of the glue coating area.

[0141] The computer control system 16 controls the direction control valve 17 according to the feedback of the automatic positioning device 34, and then controls the X-direction motion axis, the Y-direction motion axis 33, and the Z-direction motion axis 32 to lower the glue coating mold to the mobile operating platform 31, adjust the relative position of the sample 65 and the glue coating mold, so that the sample 65 is in the center of the glue coating mold, and ensure that the glue coating thickness of the four surfaces of the sample 65 is consistent during the glue coating. After adjusting the position, put down the pressing plate 29 to ensure that the sample 65 will not move during the glue coating process. The first control axis 59, the second control axis 60, the third control axis 61 and the fourth control axis 62 are adjusted by the computer control system 16 to determine the glue coating thickness, and the glue pump 24 starts to inject glue. At the same time as the glue injection, the heating plate 54 is turned on to accelerate the curing speed of the glue. It is also possible to control a certain glue injection port separately for glue injection. After waiting for a few minutes for curing, the glue coating mold is raised, and then the pressing plate 29 is raised. The telescopic arm 10 and the automatic control clamp 11 pass the sample 65 through the first transportation channel 12 and the second transportation channel 13, and dry it again in the drying area, and continue to dry for more than 48 hours.

[0142] The two glue tanks 27 can fully mix the AB glue through a stirring mixer, and then inject the mixture into the glue storage tank 21 through the first solution feeder 25 .

[0143] Imbibition and data measurement and analysis: The fifth opening and closing door 5 is opened by the computer control system 16, and the sample 65 is placed in the sample holder by the telescopic arm 10. At this time, the initial mass m0 of the sample 65 is recorded by the second analytical balance 48. The transverse and longitudinal wave velocities v of the sample 65 in the dry state are measured by using the acoustic energy converter 49 installed on the surface of the sample 65. 10s and v 10p Based on this, the initial elastic modulus of the sample 65 is obtained by averaging the transverse and longitudinal wave velocities measured by each acoustic energy converter 49:

[0144]

[0145] In the formula, E 10 is the elastic modulus before water absorption along the layer, MPa; ρ is the rock density, g / cm 3 ; is the shear wave velocity before water absorption along the layer, m / s; It is the longitudinal wave velocity before water absorption along the layer, m / s.

[0146] The thermostat 35 and the humidifier 36 are adjusted to keep the temperature and humidity of the infiltration zone constant. The height of the flexible connecting rod 50 is adjusted to lower the sample 65 into the second solution feeder 37. The acoustic energy converter 49 can record the transverse and longitudinal wave velocities v of the sample 65 in real time. 1s and v 1p In addition, the dynamic elastic modulus of the water absorption process along the layer is expressed as:

[0147]

[0148] In the formula, E 顺 is the dynamic elastic modulus during the water absorption process along the layer, MPa; is the shear wave velocity during the layer-wise water absorption process, m / s; is the longitudinal wave velocity during the layer-wise water absorption process, m / s.

[0149] The elastic modulus of sample 65 affected by water absorption along the layer can be expressed as:

[0150]

[0151] In the formula, E 顺s is the elastic modulus of the weakening of sample 65 due to water absorption along the layer, MPa.

[0152] Then, the weakening index D of sample 65 due to water absorption along the layer is 顺 for:

[0153]

[0154] The time of the layer imbibition experiment is t1, and the first analytical balance 47 and the second analytical balance 48 are combined to record the real-time mass m1 of the sample 65.

[0155] Then conduct translayer infiltration:

[0156] 1) First prepare the sample for trans-layer imbibition:

[0157] Drying: The telescopic arm 10 is controlled by the computer control system 16 to move the sample 65 to the drying area, the fifth opening and closing door 5 is closed, the temperature is adjusted to 60°C, and the drying is continued for more than 48 hours. The computer control system 16 records the mass of the sample 65 as m2 through the gravity sensor.

[0158] Gluing: Open the fourth door 4, the third door 3 and the sixth door 6 to move the sample 65 to the glue coating area, and then close the fourth door 4, the third door 3 and the sixth door 6. Adjust the first control axis 59, the second control axis 60, the fourth control axis 62 and the third control axis 61 to inject glue to the other two surfaces of the sample 65 according to the determined glue coating thickness.

[0159] Cutting: After the glue is solidified, open the sixth opening and closing door 6, the third opening and closing door 3 and the second opening and closing door 2, place the sample 65 into the laser cutting machine 8 to cut off the glue on both sides of the sample 65 for cross-layer absorption, and then close the corresponding opening and closing door.

[0160] 2) Carry out layer penetration:

[0161] The second opening and closing door 2, the fourth opening and closing door 4 and the fifth opening and closing door 5 are opened, and the sample 65 is placed in the sample holder through the telescopic arm 10. Then, the second opening and closing door 2, the fourth opening and closing door 4 and the fifth opening and closing door 5 are closed, and the thermostat 35 and the humidifier 36 are adjusted to keep the temperature and humidity of the infiltration zone constant. The flexible connecting rod 50 is controlled to lower the sample 65 to the water phase infiltration zone. The acoustic energy converter 49 records the transverse and longitudinal waves v during the transverse layer infiltration in real time. 20s and v 20p Similarly, the weakening index D of sample 65 due to water absorption through the layer can be obtained: 穿 :

[0162]

[0163] Based on this, we can judge the influence of water absorption along the layer and water absorption through the layer on the reservoir stability S, which can be specifically expressed as:

[0164]

[0165] When S is greater than 1, the weakening degree of the bedding caused by the infiltration water is higher, and the cross-layer has a higher stability; when S is equal to 1, the effects of the infiltration water on the bedding and the cross-layer are the same, so the stability of the bedding and the cross-layer is the same; when S is less than 1, the weakening degree of the cross-layer caused by the infiltration water is higher, and the bedding has a higher stability.

[0166] At the same time, the time of the interlayer imbibition experiment is t2, and the mass of sample 65 is recorded in real time as m3. Through the real-time change of the mass during the imbibition process, the imbibition index C reflecting the difference between spontaneous imbibition along the layer and through the layer can be obtained:

[0167]

[0168] When C is greater than 1, fluid migration in the layering direction is advantageous; when C is equal to 1, there is no difference in fluid migration in different directions; when C is less than 1, fluid migration in the cross-layer direction is advantageous.

[0169] Similarly, according to the above steps, the sample 65 is dropped into the third solution feeder 38 to measure the oil absorption index.

[0170] (2) Experimental study on the effect of initial water content of the same sample 65 on spontaneous imbibition of shale reservoirs

[0171] Cutting: First open the first opening and closing door, place the sample 65 on the loading platform 9, close the first opening and closing door 1, control the automatic control clamp 11 at the front end of the telescopic arm 10 through the computer control system 16 to clamp the sample 65, move it to the laser cutting machine 8, set the cutting position and size, and after the cutting is completed, clamp it out with the telescopic arm 10.

[0172] Drying: Open the second door 2, open the fourth door 4, and clamp the sample 65 through the first transport channel 12 into the drying area by the automatic control clamp 11 at the front end of the telescopic arm 10. Close the second door 2 and the fourth door 4, adjust the temperature to 60°C, and continue drying for more than 48 hours. At this time, record the mass of the sample 65 as m4.

[0173] Saturation: Open the seventh opening and closing door 7, and let the automatic control clamp 11 at the front end of the telescopic arm 10 clamp the sample 65 into the saturation zone. Close the seventh opening and closing door 7, and record the mass m5 of the saturated sample 65. At this time, the moisture content w1 of the sample 65 is:

[0174]

[0175] The seventh opening and closing door 7 is used as a channel for the sample 65 to enter the saturated zone. The function of the seventh opening and closing door 7 is not only to provide a channel for the sample 65 to enter the saturated zone, but also to ensure that the environment of the saturated zone is not disturbed by external environmental factors, thereby improving the accuracy of the experiment.

[0176] Gluing: Glue the sample in the same manner as in step (1) to conduct a layer-wise imbibition test of the sample at a moisture content of w1.

[0177] Water absorption: open the fifth opening and closing door 5, the automatic control clamp 11 at the front end of the telescopic arm 10 descends to above the second solution feeder 37 of the water phase absorption zone, adjust the thermostat 35 and the humidifier 36 to keep the temperature and humidity of the absorption zone constant, extend the telescopic arm 10 to make the sample 65 completely immersed in the water phase solution, and close the fifth opening and closing door 5.

[0178] Parameter measurement: The gravity sensor on the controllable telescopic arm 10 records the weight reading in real time. The experimental time is t3, and the mass of the sample imbibition along the layer under the condition of water content w1 is measured as m6. The interlayer imbibition experiment under the condition of water content w1 is carried out in accordance with the operation of (1), and the mass of the interlayer imbibition under the condition of water content w1 is measured as m8. Based on this, the imbibition index C reflecting the difference between the spontaneous imbibition along the layer and the interlayer under the condition of water content w1 can be obtained. w1 :

[0179]

[0180] Wherein, m7 is the mass after drying by infiltration along the layer, g; t4 is the infiltration time through the layer, h.

[0181] Similarly, the imbibition index at different water contents can be measured through the above steps.

[0182] Under the conditions of in-beam and through-beam imbibition, the effect of moisture content on the weakening index D of sample 65 w顺 , D w穿 The influences are expressed as:

[0183]

[0184] In the formula, is the shear wave velocity before water absorption along the layer at a water content of w, m / s; is the longitudinal wave velocity before water absorption along the layer at water content w, m / s; is the shear wave velocity during the water absorption process along the layer with a water content of w, m / s; is the longitudinal wave velocity during the water absorption process along the layer at a water content w, m / s; is the shear wave velocity before the water absorption of the layer with a water content of w, m / s; is the longitudinal wave velocity before water absorption under the water content w, m / s; is the shear wave velocity during water absorption in the layer with a water content of w, m / s; is the longitudinal wave velocity during the water absorption process under the moisture content w, m / s.

[0185] Similarly, the above steps can be used to measure the effects of different water content conditions on the imbibition of oil phase solution.

[0186] It should be noted that the shale spontaneous imbibition evaluation device of the present invention can complete tests under various experimental paths, including in-layer imbibition and through-layer imbibition experiments of the same sample, as well as in-layer imbibition and through-layer imbibition experiments under different saturation conditions.

[0187] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A shale spontaneous imbibition evaluation device, characterized in that: It includes a cutting area, a drying area, a saturation area, a gluing area, an infiltration area and a computer control system; the cutting area, the drying area, the gluing area and the infiltration area are arranged in sequence, and the saturation area is adjacent to the drying area; The cutting area is provided with a first opening and closing door and a second opening and closing door, a cutting assembly and a transport assembly; the transport assembly is capable of moving the sample; the computer control system is connected to both the transport assembly and the cutting assembly; The drying area is connected to the cutting area via a second opening and closing door; the drying area is provided with a first transport channel, a drying component and a fourth opening and closing door; the drying component is provided below the first transport channel, and the drying component and the first transport channel are both connected to the computer control system; The gluing area is provided with a second transport channel, a positioning device, a three-axis moving assembly, a gluing assembly, a third opening and closing door, and a sixth opening and closing door. The positioning device is connected to the three-axis moving assembly, and the positioning device is arranged on the gluing assembly; the positioning device and the three-axis moving assembly are both connected to the computer control system; the drying area is connected to the gluing area through the third opening and closing door, the second transport channel can move the sample from the third opening and closing door to the gluing assembly, and the sixth opening and closing door is arranged below the second transport channel; The infiltration zone is provided with a fifth opening and closing door and an infiltration experimental device, and the transport component can move the sample from the glue coating zone to the infiltration zone through the fifth opening and closing door; The saturation zone is provided with a seventh opening and closing door, and the saturation zone is provided with a container, the container is used to contain water; The glue coating component includes a glue coating mold, a mobile operating platform and a glue transmission component. The glue transmission component includes a glue tank, a glue pump, a glue storage tank, a glue guide hose, a glue cylinder, a pressing sheet and a glue hose connected in sequence. A piston is arranged in the glue storage tank. The mobile operating platform is arranged below the glue hose, and the glue coating mold is arranged on the mobile operating platform; the positioning device includes a position sensor and a directional control valve. The directional control valve is connected to the three-axis moving component, and the position sensor and the directional control valve are both connected to the computer control system.

2. The shale spontaneous imbibition evaluation device according to claim 1, characterized in that: The transport assembly comprises a telescopic arm and an automatic control clamp, and both the telescopic arm and the automatic control clamp are connected to the computer control system.

3. The shale spontaneous imbibition evaluation device according to claim 2, characterized in that: A weight sensor is arranged on the telescopic arm.

4. The shale spontaneous imbibition evaluation device according to claim 1, characterized in that: The cutting area is also provided with a solenoid valve, one end of which is connected to a gas supply source, and the other end of which is connected to the cutting assembly.

5. The shale spontaneous imbibition evaluation device according to claim 1, characterized in that: The cutting assembly comprises a laser cutting machine and a loading platform, and the laser cutting machine is connected to the computer control system.

6. The shale spontaneous imbibition evaluation device according to claim 5, characterized in that: A waste collection area is arranged below the loading platform, and a waste collector is also arranged on the side of the loading platform.

7. The shale spontaneous imbibition evaluation device according to claim 1, characterized in that: The drying component includes a heater, a first temperature sensor, a humidity controller and an air pump. The heater, the humidity controller and the air pump are all connected to the computer control system. The heater is arranged below the first transport channel, the first temperature sensor is connected to the first transport channel, and the heater is connected to the humidity controller.

8. The shale spontaneous imbibition evaluation device according to claim 1, characterized in that: A first liquid level sensor and a pressure detector are also arranged on the glue storage tank.

9. The shale spontaneous imbibition evaluation device according to claim 8, characterized in that: A safety valve is also arranged above the glue storage tank.

10. The shale spontaneous imbibition evaluation device according to claim 8, characterized in that: The glue storage tank is also connected to a first solution feeder.

11. The shale spontaneous imbibition evaluation device according to claim 10, characterized in that: There are two glue tanks, the glue pump is connected to one of the glue tanks, a mixing mixer is arranged between the two glue tanks, both glue tanks are connected to the inlet of the mixing mixer, one end of the first solution feeder is connected to the outlet of the mixing mixer, and the other end of the first solution feeder is connected to the glue storage tank.

12. The shale spontaneous imbibition evaluation device according to claim 1, characterized in that: The three-axis moving assembly includes an X-axis moving axis, a Y-axis moving axis and a Z-axis moving axis. The X-axis moving axis, the Y-axis moving axis and the Z-axis moving axis are perpendicular to each other, and the glue coating mold can move along the three-axis moving assembly.

13. The shale spontaneous imbibition evaluation device according to claim 1, characterized in that: The glue coating mold is a hexahedron, and the interior of each face is filled with a heating plate. The interior of the glue coating mold is a cavity, and a first glue injection port, a second glue injection port, a third glue injection port and a fourth glue injection port are provided on the upper wall, the bottom wall and two opposite side walls. The first glue injection port, the second glue injection port, the third glue injection port and the fourth glue injection port are respectively connected to a glue hose, and a first control axis, a second control axis, a third control axis and a fourth control axis are respectively provided at the first glue injection port, the second glue injection port, the third glue injection port and the fourth glue injection port.

14. The shale spontaneous imbibition evaluation device according to claim 1, characterized in that: The imbibition experimental device comprises a spontaneous imbibition heat preservation and moisture sealed system, which comprises a shell and a flexible connecting rod, a sample rotating clamp, a thermostat, a humidifier, a first analytical balance, a second analytical balance, an imbibition dish, a second liquid level sensor, an acoustic energy converter, a sample cabinet, a second temperature sensor and a humidity sensor arranged inside the shell; the humidity sensor and the second temperature sensor are arranged on the side wall of the shell, and the flexible connecting rod, the sample rotating clamp, the thermostat, the humidifier, the first analytical balance, the second analytical balance, the imbibition dish, the second liquid level sensor, the acoustic energy converter and the sample cabinet are all arranged inside the shell; The first analytical balance is connected to the sample cabinet via a flexible connecting rod, the sample rotating clamp and the acoustic energy converter are arranged inside the sample cabinet, a sample clamp is also arranged inside the sample cabinet, the humidifier and the thermostat are arranged at the bottom or side wall of the housing, the second analytical balance is arranged at the bottom of the housing, the filtration dish is arranged above the second analytical balance, and a second liquid level sensor is arranged inside the filtration dish; The infiltration and absorption dish is also connected to a water replenishment tank and an oil replenishment tank. The water replenishment tank is connected to the infiltration and absorption dish through a second solution feeder, and the oil replenishment tank is connected to the infiltration and absorption dish through a third solution feeder.

15. A method for evaluating spontaneous imbibition of shale, characterized in that: Using the shale spontaneous imbibition evaluation device according to any one of claims 1 to 14 comprises the following steps: Prepare samples by imbibition along the bedding; Carry out layer-by-layer imbibition; Preparation of translaminar imbibition samples; Conduct translayer infiltration; Preparation of samples with different saturation levels; The samples with different saturations were subjected to bedding imbibition and trans-bedding imbibition. The data after bedding imbibition and trans-bedding imbibition were processed to obtain the imbibition index and mechanical parameters under different imbibition paths.

16. The shale spontaneous imbibition evaluation method according to claim 15, characterized in that: The process of preparing the bedding imbibition sample includes: Measure sample weight and dimensions; The samples are dried in the drying area and glued in the glue coating area in turn; Ultrasonic velocity measurement was performed on the samples after glue coating to obtain the initial mechanical parameters of the samples before the layer imbibition experiment was carried out.

17. The shale spontaneous imbibition evaluation method according to claim 16, characterized in that: The bedding imbibition process includes: Measure the parameters of the bedding imbibition samples; Conduct bedding imbibition on bedding imbibition samples in the imbibition zone; Measure transverse and longitudinal wave velocities as well as weight changes before and after imbibition.

18. The shale spontaneous imbibition evaluation method according to claim 15, characterized in that: The process of preparing the translaminar imbibition sample includes: The samples are dried in the drying area and glued in the glue coating area in turn; Laser cutting is performed on the glue-coated samples according to the set layer penetration sample index; Ultrasonic velocity measurement was performed on the cut samples to obtain the mechanical parameters of the samples before the penetration experiment was carried out.

19. The shale spontaneous imbibition evaluation method according to claim 18, characterized in that: The translaminar imbibition process includes: Carry out parameter measurement of the through-layer imbibition samples; Conducting trans-layer imbibition on the trans-layer imbibition samples in the imbibition area; Measure transverse and longitudinal wave velocities as well as weight changes before and after imbibition.

20. The shale spontaneous imbibition evaluation method according to claim 15, characterized in that: The sample preparation process for different saturation levels includes: Different samples are dried in the drying area and glued in the glue coating area in turn; Laser cutting is performed on different samples after glue coating according to the set sample indexes of different saturation levels; Soaking the cut different samples in the saturation zone according to the set different saturation sample indexes to obtain samples with different saturations; Ultrasonic velocity measurements were performed on samples with different saturations to obtain the mechanical parameters of samples with different saturations before conducting the in-bedding imbibition and through-bedding imbibition experiments.

21. The shale spontaneous imbibition evaluation method according to claim 20, characterized in that: Samples with different saturations were subjected to bedding imbibition and trans-bedding imbibition, and the data after bedding imbibition and trans-bedding imbibition were processed to obtain the imbibition index and mechanical parameters under different imbibition paths, including: The samples with different saturation were imbibed along the layer in the imbibition zone, and the transverse and longitudinal wave velocities as well as the weight changes before and after the imbibition were measured. The samples with different saturation were imbibed through the layers in the imbibition zone, and the transverse and longitudinal wave velocities as well as the weight changes before and after the imbibition were measured. After data processing of in-beam imbibition and through-beam imbibition, the imbibition index and mechanical parameters under different imbibition paths were obtained.

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