Safety type damaged state rock hydrogen permeation simulation device and method

Abstract

The invention discloses a safety type damaged state rock hydrogen permeation simulation device and method.The simulation device comprises a box body, a simulation mechanism, a hydrogen injection mechanism and an explosion-proof mechanism, and the simulation mechanism comprises a pressure box, a lower cushion block, a thermal shrinkage sleeve, an upper pressing block, an axial pressure assembly and a confining pressure assembly; and the hydrogen injection mechanism is communicated with the gas inlet hole and the gas outlet hole and is used for injecting gas with preset gas pressure and preset hydrogen concentration into the thermal shrinkable sleeve. The device has the beneficial effects that gas with preset pressure and preset hydrogen concentration is continuously injected into the rock sample in the thermal shrinkable sleeve through the hydrogen injection mechanism, the influence of different hydrogen environments on rock mechanical properties can be simulated, meanwhile, the first hydrogen concentration detection piece continuously monitors the hydrogen concentration in the box body, and if the concentration exceeds a preset safety threshold value, the hydrogen concentration is detected. And the fan is immediately started, and hydrogen in the box body is discharged to an outdoor safe area, so that explosion accidents caused by hydrogen leakage can be avoided, and the safety of an experiment process is improved.

Description

Technical Field

[0001] The invention relates to the technical field of geotechnical engineering experimental devices, and in particular to a safe type damaged state rock hydrogen permeation simulation device and method. Background Art

[0002] In the research process of materials science and geotechnical engineering, triaxial compression test is an important testing method, which is widely used to simulate the mechanical properties of rock samples under complex stress states. By applying axial pressure and lateral confining pressure to rock samples, triaxial compression test can reproduce the multi-directional stress environment faced by rock samples in actual engineering applications, thereby providing key data support for evaluating the strength, deformation characteristics and failure mechanism of rock samples. With the continuous and in-depth development of scientific research, exploring the changes in the characteristics of rock samples under the action of hydrogen environment has become a hot topic. In the field of materials science, the interaction between hydrogen and various materials may cause changes in the microstructure of the material, thereby affecting its macroscopic mechanical properties.

[0003] In the field of underground hydrogen storage, long-term high-pressure environments cause the rocks around the hydrogen storage reservoir to gradually accumulate damage. There is a continuous interaction between these damaged rocks and hydrogen, in which hydrogen significantly affects the mechanical properties of the rocks. This interaction may further cause safety hazards in the gas storage reservoir and pose a potential threat to the stability and safety of the hydrogen storage system.

[0004] However, as a special gas, hydrogen has a flammable and explosive nature, which brings huge safety hazards to related experimental research. The explosion limit range of hydrogen is relatively wide (4.0%-75.6%), and it is very easy to form an explosive mixed gas in the air. In the experimental environment, even a small leak of hydrogen, once mixed with air to reach the explosion limit, encountering a fire source (such as electric sparks generated by electrical equipment, static sparks generated by friction, etc.), may cause a violent explosion reaction. Although traditional triaxial compression instruments have been widely used in the study of rock mechanical properties, they are often not specially designed for hydrogen environments and cannot effectively guarantee the safety of hydrogen during the experiment. Since hydrogen is flammable and explosive, and the electrical system of the device is not explosion-proof, during the experiment, if hydrogen leaks or the pressure is out of control, it is very easy to cause an explosion accident. This will not only cause irreparable damage to the experimental equipment, but also directly threaten the life safety of the experimenters. Once an explosion occurs, the personnel in the laboratory may suffer serious injuries or even lose their lives. At the same time, the impact and destructive force generated by the explosion may spread to the surrounding areas, causing a larger range of safety accidents. In addition, when studying the effect of hydrogen on the mechanical properties of rock samples, precise hydrogen regulation is the key. However, the traditional triaxial compression experimental device lacks effective hydrogen regulation means, making it difficult to accurately control parameters such as hydrogen pressure and concentration, and unable to simulate the actual stress state of rocks under different hydrogen environments.

[0005] Therefore, developing a triaxial compression experimental device with hydrogen explosion-proof function and capable of precisely controlling hydrogen is of great significance for promoting the study of the property changes of rock samples under the action of hydrogen environment and ensuring the integrity of experimental equipment and personnel safety. Summary of the invention

[0006] The purpose of the present invention is to overcome the above-mentioned technical deficiencies and propose a device and method for simulating the influence of hydrogen on the mechanical properties of rocks in a damaged state, so as to solve the technical problems that the rock mechanical properties testing device in the prior art cannot simulate the influence of different hydrogen environments on the mechanical properties of rocks and does not have a hydrogen explosion-proof function.

[0007] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0008] The present invention provides a safe damaged rock hydrogen permeation simulation device, comprising:

[0009] Box;

[0010] A simulation mechanism, the simulation mechanism comprising a pressure box, a lower pad, a heat shrink sleeve, an upper pressure block, an axial pressure assembly and a confining pressure assembly, the pressure box is fixed in the box body, the lower pad is fixed in the pressure box, the heat shrink sleeve is used to be sleeved on the rock sample, one end of the heat shrink sleeve is provided with an air inlet hole, the other end of the heat shrink sleeve is provided with an air outlet hole, one end of the heat shrink sleeve is in contact with the lower pad, the upper pressure block is pressed on the other end of the heat shrink sleeve, the axial pressure assembly is used to apply pressure to the upper pressure block, and the confining pressure assembly is used to fill the pressure box with liquid and keep the pressure of the liquid at a preset confining pressure;

[0011] a hydrogen injection mechanism, the hydrogen injection mechanism being connected to the air inlet and the air outlet and used for injecting gas of a preset air pressure and a preset hydrogen concentration into the heat shrink sleeve; and

[0012] The explosion-proof mechanism comprises a first hydrogen concentration detector and a fan. The first hydrogen concentration detector is arranged in the box body and is used to detect the hydrogen concentration in the box body. The fan is used to exhaust the air in the box body.

[0013] In some embodiments, the pressure box includes a bottom plate, a cylinder and a top plate, the lower end of the cylinder is fixed to the bottom plate, a clearance hole coaxial with the air inlet is provided on the bottom plate, the top plate is fixed to the upper end of the cylinder, a socket is provided on the top plate, the upper pressure block is sealingly slidably arranged in the socket, the upper end of the upper pressure block is located at the upper end of the top plate, an air outlet channel is formed in the upper pressure block, the lower end of the air outlet channel is connected to the air outlet, and the upper end of the upper pressure block is provided with an air outlet interface connected to the upper end of the air outlet channel.

[0014] In some embodiments, the hydrogen injection mechanism includes an air intake component and an exhaust component; the air intake component includes a hydrogen bottle, a nitrogen bottle, a first regulating valve, a second regulating valve, a mixer, an air intake pump and an air intake manifold, one end of the first regulating valve is connected to the outlet of the hydrogen bottle, the other end of the first regulating valve is connected to the first inlet of the mixer, one end of the second regulating valve is connected to the outlet of the nitrogen bottle, the other end of the second regulating valve is connected to the second inlet of the mixer, the outlet of the mixer is connected to the inlet of the air intake pump, the outlet of the air intake pump is connected to one end of the air intake manifold, and the other end of the air intake manifold is connected to the air intake hole after passing through the give way hole; the exhaust component includes an exhaust pipe and a recovery bottle, one end of the exhaust pipe is connected to the air outlet interface, and the other end of the exhaust pipe is connected to the inlet of the recovery bottle.

[0015] In some embodiments, the air intake assembly further includes a first air intake pipe, one end of the first air intake pipe is in communication with the other end of the first regulating valve, and the other end of the first air intake pipe is in communication with the first inlet of the mixer.

[0016] In some embodiments, the air intake assembly further includes a second air intake pipe, one end of the second air intake pipe is connected to the other end of the second regulating valve, and the other end of the second air intake pipe is connected to the second inlet of the mixer.

[0017] In some embodiments, a pressure gauge and a flow meter are provided on the intake manifold, and a second hydrogen concentration detector is provided on the exhaust pipe.

[0018] In some embodiments, the axial pressure assembly includes a bracket, a fixed plate and a cylinder, one end of the bracket is fixed to the top plate, the fixed plate is fixed to the other end of the bracket, the cylinder body of the cylinder is fixed to the fixed plate, and the output shaft of the cylinder is connected to the upper pressure block.

[0019] In some embodiments, an oil filling hole is opened on the base plate; the confining pressure assembly includes an oil tank, an oil pump and an oil filling pipe, the inlet of the oil pump is connected to the outlet of the oil tank, one end of the oil filling pipe is connected to the outlet of the oil pump, and the other end of the oil filling pipe is connected to the oil filling hole.

[0020] In some embodiments, the safety-type damaged state rock hydrogen permeation simulation device also includes a computer control system, and the computer control system is electrically connected to the oil cylinder and the oil pump.

[0021] The present invention also provides a method for simulating hydrogen permeation of rocks in a safe damaged state, which is applicable to the device for simulating hydrogen permeation of rocks in a safe damaged state and comprises the following steps:

[0022] S1. Prepare multiple rock samples of the same lithology and equal volume, put one of the rock samples into a heat shrink sleeve, then place the heat shrink sleeve on the lower pad, press the heat shrink sleeve with the upper pressing block, and connect the air inlet and outlet of the heat shrink sleeve to the hydrogen injection mechanism;

[0023] S2. Use the confining pressure assembly to inject pressure liquid into the pressure box until the pressure box is completely filled, and then adjust the confining pressure assembly to keep the pressure of the pressure liquid at a preset confining pressure level;

[0024] S3, applying pressure to the upper pressing block through the axial pressure assembly, thereby transmitting the pressure to the rock sample;

[0025] S4. The hydrogen injection mechanism continuously injects gas with a preset pressure and a preset hydrogen concentration into the rock sample in the heat shrink sleeve to observe changes in the mechanical properties of the rock sample;

[0026] S5. During the experiment, the first hydrogen concentration detection component continuously monitors the hydrogen concentration in the box. If the concentration exceeds the preset safety threshold, the fan is immediately started to discharge the hydrogen in the box to the outdoor safe area;

[0027] S6. Carry out the same test process on other rock samples one by one. During the test of different rock samples, the gas pressure and hydrogen concentration of the gas injected into the heat shrink sleeve by the hydrogen injection mechanism are different. Compare the differences in the changes in the mechanical properties of the rock samples in each experiment, and obtain the influence of hydrogen concentration and gas pressure on the mechanical properties of rock.

[0028] Compared with the prior art, the beneficial effects of the safe damaged state rock hydrogen permeation simulation device and method provided by the present invention are: gas with a preset pressure and a preset hydrogen concentration is continuously injected into the rock sample in the heat shrink sleeve by the hydrogen injection mechanism, so as to simulate the influence of different hydrogen environments on the mechanical properties of the rock. At the same time, the first hydrogen concentration detection component continuously monitors the hydrogen concentration in the box. If the concentration exceeds the preset safety threshold, the fan is immediately started to discharge the hydrogen in the box to the outdoor safe area, thereby avoiding explosion accidents due to hydrogen leakage and improving the safety of the experimental process. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1It is a schematic structural diagram of a safety-type damaged state rock hydrogen permeation simulation device provided by an embodiment of the present invention;

[0030] Figure 2 yes Figure 1 Structural schematic diagram of the simulation mechanism and the gas injection mechanism;

[0031] Figure 3 yes Figure 1 A partial enlarged view of the middle area A;

[0032] Figure 4 yes Figure 1 A schematic diagram of the top view of the upper pressing block in FIG.

[0033] Figure 5 yes Figure 1 Schematic diagram of the three-dimensional structure of the box;

[0034] Description of the accompanying drawings: 1-box, 11-cabinet door, 111-explosion-proof glass, 12-partition, 2-simulation mechanism, 21-pressure box, 211-bottom plate, 212-cylinder, 213-top plate, 22-lower pad, 23-heat shrink sleeve, 24-upper pressure block, 241-air outlet channel, 242-air outlet interface, 25-axial pressure assembly, 251-bracket, 252-fixing plate, 253-oil cylinder, 26-confining pressure assembly, 261-oil tank, 262-oil pump, 263-oil injection pipe, 3-hydrogen injection mechanism, 31-air intake group Parts, 311-hydrogen cylinder, 312-nitrogen cylinder, 313-first regulating valve, 314-second regulating valve, 315-mixer, 316-intake pump, 317-intake main pipe, 3171-pressure gauge, 3172-flow meter, 318-first intake pipe, 319-second intake pipe, 32-exhaust assembly, 321-exhaust pipe, 3211-second hydrogen concentration detection part, 322-recovery bottle, 4-explosion-proof mechanism, 41-first hydrogen concentration detection part, 42-fan, 5-rock sample, 6-computer control system. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0036] In order to solve the technical problems that the rock mechanical properties testing device in the prior art cannot simulate the influence of different hydrogen environments on the rock mechanical properties and does not have a hydrogen explosion-proof function, the present invention provides a safe hydrogen penetration simulation device and method for rocks in a damaged state.

[0037] See also Figure 1-Figure 5 , Figure 1It is a structural schematic diagram of a safety-type damaged state rock hydrogen permeation simulation device in one embodiment of the present invention. The safety-type damaged state rock hydrogen permeation simulation device includes a box 1, a simulation mechanism 2, a hydrogen injection mechanism 3 and an explosion-proof mechanism 4.

[0038] The cabinet 1 is provided with a cabinet door 11, so that it is convenient to open the cabinet door 11 and operate the equipment in the cabinet 1. The cabinet 1 is also provided with a plurality of air holes, and a one-way valve is provided on the air holes. The one-way valve only allows external gas to enter the cabinet 1, and does not allow the gas in the cabinet 1 to escape. The cabinet door 11 is inlaid with explosion-proof glass 111, so that it is convenient to observe the operation of the equipment in the cabinet 1.

[0039] The simulation mechanism 2 includes a pressure box 21, a lower pad 22, a heat shrink sleeve 23, an upper pressure block 24, an axial pressure assembly 25 and a confining pressure assembly 26. The pressure box 21 is fixed in the box body 1, the lower pad 22 is fixed in the pressure box 21, the heat shrink sleeve 23 is used to be sleeved on the rock sample 5, one end of the heat shrink sleeve 23 is provided with an air inlet hole, the other end of the heat shrink sleeve 23 is provided with an air outlet hole, one end of the heat shrink sleeve 23 is in contact with the lower pad 22, the upper pressure block 24 is pressed on the other end of the heat shrink sleeve 23, the axial pressure assembly 25 is used to apply pressure to the upper pressure block 24, and the confining pressure assembly 26 is used to fill the pressure box 21 with liquid and keep the pressure of the liquid at a preset confining pressure.

[0040] The specific method of using the heat shrink sleeve 23 is as follows: use a hot drying gun to allow the heat shrink sleeve to shrink after heating and tightly wrap the cylindrical rock sample, then place the rock sample wrapped with the heat shrink sleeve between the upper and lower pressure heads, and use an elastic wire ring to tightly clamp the heat shrink sleeve on the upper and lower pressure heads to prevent the oil in the cavity from entering the heat shrink sleeve and contaminating the rock sample.

[0041] The hydrogen injection mechanism 3 is connected to both the air inlet and the air outlet, and is used to inject gas with a preset air pressure and a preset hydrogen concentration into the heat shrink sleeve 23 .

[0042] The explosion-proof mechanism 4 includes a first hydrogen concentration detector 41 and a fan 42 . The first hydrogen concentration detector 41 is disposed in the box 1 and is used to detect the hydrogen concentration in the box 1 . The fan 42 is used to exhaust the air in the box 1 .

[0043] The simulation method includes the following steps:

[0044] S1. Prepare multiple rock samples 5 of the same lithology and equal volume, put one of the rock samples 5 into the heat shrink sleeve 23, then put the heat shrink sleeve 23 on the lower pad 22, press the heat shrink sleeve 23 with the upper pressing block 24, and connect the air inlet and air outlet of the heat shrink sleeve 23 to the hydrogen injection mechanism 3;

[0045] S2, using the confining pressure assembly 26 to inject pressure liquid into the pressure box 21 until the pressure box 21 is completely filled, and then adjusting the confining pressure assembly 26 to keep the pressure of the pressure liquid at a preset confining pressure level, wherein the setting of the confining pressure is intended to simulate the pressure environment of underground rocks;

[0046] S3. Apply pressure to the upper pressing block 24 through the axial pressure assembly 25, thereby transferring the pressure to the rock sample 5. This step simulates the vertical stress of the overlying rock strata on the underground rock.

[0047] S4, the hydrogen injection mechanism 3 continuously injects gas with a preset pressure and a preset hydrogen concentration into the heat shrink sleeve 23 to observe changes in the mechanical properties of the rock sample 5, such as whether the rock sample 5 is deformed or cracked;

[0048] S5. During the experiment, the first hydrogen concentration detection element 41 continuously monitors the hydrogen concentration in the box 1. If the concentration exceeds the preset safety threshold, the fan 42 is immediately started to discharge the hydrogen in the box 1 to the outdoor safe area;

[0049] S6. Perform the same test process on other rock samples 5 one by one. During the test process of different rock samples 5, the gas pressure and hydrogen concentration of the gas injected into the heat shrink sleeve 23 by the hydrogen injection mechanism 3 are different. The differences in the changes in the mechanical properties of the rock samples 5 in each experiment are compared to obtain the influence of hydrogen concentration and gas pressure on the mechanical properties of rock.

[0050] The technical solution provided by the present invention can simulate the influence of different hydrogen environments on the mechanical properties of rocks by continuously injecting gas of preset pressure and preset hydrogen concentration into the heat shrink sleeve 23 through the hydrogen injection mechanism 3. At the same time, the first hydrogen concentration detection component 41 continuously monitors the hydrogen concentration in the box 1. If the concentration exceeds the preset safety threshold, the fan 42 is immediately started to discharge the hydrogen in the box 1 to the outdoor safe area, thereby avoiding explosion accidents due to hydrogen leakage and improving the safety of the experimental process.

[0051] In one embodiment, see Figure 1-Figure 3 The pressure box 21 includes a bottom plate 211, a cylinder 212 and a top plate 213. The lower end of the cylinder 212 is fixed to the bottom plate 211. The bottom plate 211 is provided with a clearance hole coaxial with the air inlet. The top plate 213 is fixed to the upper end of the cylinder 212. The top plate 213 is provided with a plug hole. The upper pressing block 24 is sealingly and slidably arranged in the plug hole. The upper end of the upper pressing block 24 is located at the upper end of the top plate 213. An air outlet channel 241 is formed in the upper pressing block 24. The lower end of the air outlet channel 241 is communicated with the air outlet. The upper end of the upper pressing block 24 is provided with an air outlet interface 242 communicated with the upper end of the air outlet channel 241.

[0052] In one embodiment, see Figure 1-Figure 3 The hydrogen injection mechanism 3 includes an air intake component 31 and an exhaust component 32; the air intake component 31 includes a hydrogen bottle 311, a nitrogen bottle 312, a first regulating valve 313, a second regulating valve 314, a mixer 315, an air intake pump 316 and an air intake manifold 317, one end of the first regulating valve 313 is connected to the outlet of the hydrogen bottle 311, the other end of the first regulating valve 313 is connected to the first inlet of the mixer 315, one end of the second regulating valve 314 is connected to the outlet of the nitrogen bottle 312, and the second regulating valve The other end of 314 is connected to the second inlet of the mixer 315, the outlet of the mixer 315 is connected to the inlet of the air intake pump 316, the outlet of the air intake pump 316 is connected to one end of the air intake manifold 317, and the other end of the air intake manifold 317 is connected to the air intake hole after passing through the clearance hole; the exhaust assembly 32 includes an exhaust pipe 321 and a recovery bottle 322, one end of the exhaust pipe 321 is connected to the air outlet interface 242, and the other end of the exhaust pipe 321 is connected to the inlet of the recovery bottle 322. It should be understood that the volume of the recovery bottle 322 should be much larger than the sum of the volumes of the hydrogen bottle 311 and the nitrogen bottle 312, so that the gas can be discharged into the recovery bottle 322 smoothly.

[0053] In this embodiment, the nitrogen bottle 312 serves as a supply source for hydrogen and nitrogen respectively. The first regulating valve 313 controls the flow rate of hydrogen flowing out of the hydrogen bottle 311. By adjusting the opening of the first regulating valve 313, the amount of hydrogen entering the mixer 315 can be accurately controlled. The second regulating valve 314 controls the flow rate of nitrogen flowing out of the nitrogen bottle 312. Similarly, by adjusting the opening of the second regulating valve 314, the amount of nitrogen entering the mixer 315 can be accurately controlled. Hydrogen and nitrogen are mixed in a certain proportion in the mixer 315. The mixing ratio is jointly determined by the opening of the first regulating valve 313 and the second regulating valve 314. The mixed gas is pressurized by the air intake pump 316. The air intake pump 316 provides the necessary power to transport the mixed gas to the air intake manifold 317. The air intake manifold 317 transports the mixed gas into the heat shrink sleeve 23 to complete the gas injection process. After the gas reacts with the rock sample 5 in the heat shrink sleeve 23, it is discharged through the gas outlet interface 242. The discharged waste gas is guided to the recovery bottle 322 through the exhaust pipe 321. The recovery bottle 322 is used to collect and process the waste gas to prevent it from being directly discharged into the environment and causing pollution. In this embodiment, the mixing ratio of hydrogen and nitrogen can be controlled by the opening of the first regulating valve 313 and the second regulating valve 314, thereby controlling the hydrogen concentration in the gas in the heat shrink sleeve 23, and the pressure in the heat shrink sleeve 23 can be controlled by the air intake pump 316.

[0054] It should be pointed out that the second regulating valve 314 may also be kept in a closed state, so as to simulate and study only the influence of hydrogen pressure on the mechanical properties of rock under the pure hydrogen permeation state.

[0055] In one embodiment, see Figure 1-Figure 3 The air intake assembly 31 further includes a first air intake pipe 318 , one end of which is connected to the other end of the first regulating valve 313 , and the other end of the first air intake pipe 318 is connected to the first inlet of the mixer 315 .

[0056] In one embodiment, see Figure 1-Figure 3 The air intake assembly 31 further includes a second air intake pipe 319 , one end of the second air intake pipe 319 is connected to the other end of the second regulating valve 314 , and the other end of the second air intake pipe 319 is connected to the second inlet of the mixer 315 .

[0057] In one embodiment, see Figure 1-Figure 3 The intake manifold 317 is provided with a pressure gauge 3171 and a flow meter 3172, and the exhaust pipe 321 is provided with a second hydrogen concentration detection element 3211. The second hydrogen concentration detection element 3211 can detect the hydrogen concentration in the gas in the exhaust pipe 321, so as to calculate the hydrogen concentration in the heat shrink sleeve 23.

[0058] In one embodiment, see Figure 1-Figure 3 The axial pressure assembly 25 includes a bracket 251, a fixed plate 252 and a cylinder 253. One end of the bracket 251 is fixed to the top plate 213, the fixed plate 252 is fixed to the other end of the bracket 251, the cylinder body of the cylinder 253 is fixed to the fixed plate 252, and the output shaft of the cylinder 253 is connected to the upper pressure block 24.

[0059] In one embodiment, see Figure 1-Figure 3 An oil filling hole is provided on the bottom plate 211; the confining pressure assembly 26 includes an oil tank 261, an oil pump 262 and an oil filling pipe 263, the inlet of the oil pump 262 is connected to the outlet of the oil tank 261, one end of the oil filling pipe 263 is connected to the outlet of the oil pump 262, and the other end of the oil filling pipe 263 is connected to the oil filling hole, and a pressure detection device is provided on the oil filling pipe 263 for detecting the pressure of the output liquid, so as to ensure that the confining pressure of the rock sample 5 is maintained at a preset pressure.

[0060] In one embodiment, see Figure 1-Figure 3 The safety-type damaged state rock hydrogen permeation simulation device also includes a computer control system 6, and the computer control system 6 is electrically connected to the oil cylinder 253 and the oil pump 262.

[0061] In one embodiment, see Figure 1-Figure 3 A partition 12 is provided in the box body 1, and the partition 12 is used to isolate the hydrogen injection mechanism 3 from other structures, thereby improving safety.

[0062] The present invention also provides a method for simulating hydrogen permeation of rocks in a safe damaged state, which is applicable to the device for simulating hydrogen permeation of rocks in a safe damaged state and comprises the following steps:

[0063] S1. Prepare multiple rock samples 5 of the same lithology and equal volume, put one of the rock samples 5 into the heat shrink sleeve 23, then put the heat shrink sleeve 23 on the lower pad 22, press the heat shrink sleeve 23 with the upper pressing block 24, and connect the air inlet and air outlet of the heat shrink sleeve 23 to the hydrogen injection mechanism 3;

[0064] S2, using the confining pressure assembly 26 to inject pressure liquid into the pressure box 21 until the pressure box 21 is completely filled, and then adjusting the confining pressure assembly 26 to keep the pressure of the pressure liquid at a preset confining pressure level, wherein the setting of the confining pressure is intended to simulate the pressure environment of underground rocks;

[0065] S3. Apply pressure to the upper pressing block 24 through the axial pressure assembly 25, thereby transferring the pressure to the rock sample 5. This step simulates the vertical stress of the overlying rock strata on the underground rock.

[0066] S4, the hydrogen injection mechanism 3 continuously injects gas with a preset pressure and a preset hydrogen concentration into the heat shrink sleeve 23 to observe changes in the mechanical properties of the rock sample 5, such as whether the rock sample 5 is deformed or cracked;

[0067] S5. During the experiment, the first hydrogen concentration detection element 41 continuously monitors the hydrogen concentration in the box 1. If the concentration exceeds the preset safety threshold, the fan 42 is immediately started to discharge the hydrogen in the box 1 to the outdoor safe area;

[0068] S6. Perform the same test process on other rock samples 5 one by one. During the test process of different rock samples 5, the gas pressure and hydrogen concentration of the gas injected into the heat shrink sleeve 23 by the hydrogen injection mechanism 3 are different. The differences in the changes in the mechanical properties of the rock samples 5 in each experiment are compared to obtain the influence of hydrogen concentration and gas pressure on the mechanical properties of rock.

[0069] The technical solution provided by the present invention can simulate the influence of different hydrogen environments on the mechanical properties of rocks by continuously injecting gas of preset pressure and preset hydrogen concentration into the heat shrink sleeve 23 through the hydrogen injection mechanism 3. At the same time, the first hydrogen concentration detection component 41 continuously monitors the hydrogen concentration in the box 1. If the concentration exceeds the preset safety threshold, the fan 42 is immediately started to discharge the hydrogen in the box 1 to the outdoor safe area, thereby avoiding explosion accidents due to hydrogen leakage and improving the safety of the experimental process.

[0070] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A safe damaged rock hydrogen permeation simulation device, characterized in that: include: Box; A simulation mechanism, the simulation mechanism comprising a pressure box, a lower pad, a heat shrink sleeve, an upper pressure block, an axial pressure assembly and a confining pressure assembly, the pressure box is fixed in the box body, the lower pad is fixed in the pressure box, the heat shrink sleeve is used to be sleeved on the rock sample, one end of the heat shrink sleeve is provided with an air inlet hole, the other end of the heat shrink sleeve is provided with an air outlet hole, one end of the heat shrink sleeve is in contact with the lower pad, the upper pressure block is pressed on the other end of the heat shrink sleeve, the axial pressure assembly is used to apply pressure to the upper pressure block, and the confining pressure assembly is used to fill the pressure box with liquid and keep the pressure of the liquid at a preset confining pressure; a hydrogen injection mechanism, the hydrogen injection mechanism being connected to the air inlet and the air outlet and used for injecting gas of a preset air pressure and a preset hydrogen concentration into the rock sample wrapped by the heat shrink sleeve; and The explosion-proof mechanism comprises a first hydrogen concentration detector and a fan. The first hydrogen concentration detector is arranged in the box body and is used to detect the hydrogen concentration in the box body. The fan is used to exhaust the air in the box body.

2. The safe damaged rock hydrogen permeation simulation device according to claim 1 is characterized in that: The pressure box includes a bottom plate, a cylinder and a top plate, the lower end of the cylinder is fixed to the bottom plate, a clearance hole coaxial with the air inlet is provided on the bottom plate, the top plate is fixed to the upper end of the cylinder, a socket is provided on the top plate, the upper pressure block is sealingly and slidably arranged in the socket, the upper end of the upper pressure block is located at the upper end of the top plate, an air outlet channel is formed in the upper pressure block, the lower end of the air outlet channel is connected with the air outlet, and the upper end of the upper pressure block is provided with an air outlet interface connected with the upper end of the air outlet channel.

3. The safe damaged rock hydrogen permeation simulation device according to claim 2 is characterized in that: The hydrogen injection mechanism includes an air intake component and an exhaust component; The air intake assembly includes a hydrogen bottle, a nitrogen bottle, a first regulating valve, a second regulating valve, a mixer, an air intake pump and an air intake manifold, one end of the first regulating valve is communicated with the outlet of the hydrogen bottle, the other end of the first regulating valve is communicated with the first inlet of the mixer, one end of the second regulating valve is communicated with the outlet of the nitrogen bottle, the other end of the second regulating valve is communicated with the second inlet of the mixer, the outlet of the mixer is communicated with the inlet of the air intake pump, the outlet of the air intake pump is communicated with one end of the air intake manifold, and the other end of the air intake manifold is communicated with the air intake hole after passing through the give way hole; The exhaust assembly includes an exhaust pipe and a recovery bottle, one end of the exhaust pipe is connected to the air outlet interface, and the other end of the exhaust pipe is connected to the inlet of the recovery bottle.

4. The safe damaged rock hydrogen permeation simulation device according to claim 3 is characterized in that: The air intake assembly further includes a first air intake pipe, one end of which is communicated with the other end of the first regulating valve, and the other end of the first air intake pipe is communicated with the first inlet of the mixer.

5. The safe damaged rock hydrogen permeation simulation device according to claim 3 is characterized in that: The air intake assembly further includes a second air intake pipe, one end of which is communicated with the other end of the second regulating valve, and the other end of the second air intake pipe is communicated with the second inlet of the mixer.

6. The safe damaged rock hydrogen permeation simulation device according to claim 3 is characterized in that: The intake manifold is provided with a pressure gauge and a flow meter, and the exhaust pipe is provided with a second hydrogen concentration detection component.

7. The safe damaged rock hydrogen permeation simulation device according to claim 2 is characterized in that: The axial pressure assembly includes a bracket, a fixing plate and a cylinder, one end of the bracket is fixed to the top plate, the fixing plate is fixed to the other end of the bracket, the cylinder body of the cylinder is fixed to the fixing plate, and the output shaft of the cylinder is connected to the upper pressure block.

8. The safe damaged rock hydrogen permeation simulation device according to claim 7 is characterized in that: The bottom plate is provided with an oil filling hole; The confining pressure assembly includes an oil tank, an oil pump and an oil filling pipe, the inlet of the oil pump is connected to the outlet of the oil tank, one end of the oil filling pipe is connected to the outlet of the oil pump, and the other end of the oil filling pipe is connected to the oil filling hole.

9. The safe damaged rock hydrogen permeation simulation device according to claim 8 is characterized in that: It also includes a computer control system, which is electrically connected to the oil cylinder and the oil pump.

10. A method for simulating hydrogen permeation in rocks in a safe damaged state, characterized in that: The invention is applicable to the safe damaged state rock hydrogen permeation simulation device as claimed in any one of claims 1 to 9, and comprises the following steps: S1. Prepare multiple rock samples of the same lithology and equal volume, put one of the rock samples into a heat shrink sleeve, then place the heat shrink sleeve on the lower pad, press the heat shrink sleeve with the upper pressing block, and connect the air inlet and outlet of the heat shrink sleeve to the hydrogen injection mechanism; S2. Use the confining pressure assembly to inject pressure liquid into the pressure box until the pressure box is completely filled, and then adjust the confining pressure assembly to keep the pressure of the pressure liquid at a preset confining pressure level; S3, applying pressure to the upper pressing block through the axial pressure assembly, thereby transmitting the pressure to the rock sample; S4. The hydrogen injection mechanism continuously injects gas with a preset pressure and a preset hydrogen concentration into the rock sample in the heat shrink sleeve to observe changes in the mechanical properties of the rock sample; S5. During the experiment, the first hydrogen concentration detection component continuously monitors the hydrogen concentration in the box. If the concentration exceeds the preset safety threshold, the fan is immediately started to discharge the hydrogen in the box to the outdoor safe area; S6. Carry out the same test process on other rock samples one by one. During the test of different rock samples, the gas pressure and hydrogen concentration of the gas injected into the heat shrink sleeve by the hydrogen injection mechanism are different. Compare the differences in the changes in the mechanical properties of the rock samples in each experiment, and obtain the influence of hydrogen concentration and gas pressure on the mechanical properties of rock.

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