Coal and rock water absorption experimental device and experimental method

Abstract

The present invention discloses a coal rock water absorption experimental device and an experimental method, the coal rock water absorption experimental device comprises a frame, an air bag, a water injector and a liquid reservoir, the air bag is arranged on the frame, the air bag is annular and is sleeved on the coal rock sample and fits with the side of the coal rock sample, and the air bag has an air nozzle; the water injector is arranged on the frame, the water injector has a water injection surface, a liquid storage cavity, and a liquid inlet, an exhaust port and a water permeable hole connected with the liquid storage cavity, the water injection surface is used to fit with the end surface of the coal rock sample, and the water permeable hole is arranged on the water injection surface; the liquid reservoir is used to contain the water injection reagent, the liquid reservoir has a container port, and the container port is connected with the liquid inlet through a water inlet pipe. The coal rock water absorption experimental device and the experimental method can simulate the forward and reverse seepage water absorption process of coal rock in coal seam water injection, characterize the seepage water absorption law of coal rock samples under different head pressures and water injection reagents, and provide a basis for determining the water injection process parameters of coal seam water injection.

Description

Technical Field

[0001] The invention relates to the technical field of mining, and in particular to a coal rock water absorption experimental device and an experimental method. Background Art

[0002] Coal seam water injection refers to the use of drilling holes to inject pressurized water into coal seams before mining. Pre-wetting the coal body has the effects of reducing the amount of coal dust, displacing gas, and preventing rock bursts. At present, coal seam water injection is a common way to prevent rock bursts. During the coal seam water injection process, it is necessary to determine parameters such as water injection reagents, water injection pressure, and water injection time, so that the coal rock can be infiltrated with water to reduce its rock burst risk.

[0003] At present, for the water absorption experimental devices for coal and rock samples, most of them adopt the method of bonding the coal and rock samples to the experimental devices to provide a water absorption environment for the coal and rock samples, which may cause water leakage and lead to large experimental measurement errors. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, an embodiment of the present invention proposes a coal rock water absorption experimental device and an experimental method to improve the experimental accuracy of the coal rock water absorption experiment.

[0006] The coal rock water absorption experimental device of the embodiment of the present invention includes a frame, an air bag, a water injector and a liquid reservoir, wherein the air bag is arranged on the frame, the air bag is annular and is sleeved on the coal rock sample and fits with the side of the coal rock sample, and the air bag has an air nozzle; the water injector is arranged on the frame, the water injector has a water injection surface, a liquid storage cavity, and a liquid inlet, an exhaust port and a water permeable hole connected to the liquid storage cavity, the water injection surface is used to fit with the end face of the coal rock sample, and the water permeable hole is arranged on the water injection surface; the liquid reservoir is used to hold water injection reagent, the liquid reservoir has a container mouth, and the container mouth is connected to the liquid inlet through a water inlet pipe.

[0007] The coal rock water absorption test device of the embodiment of the present invention inflates the airbag on the frame with gas medium so that the airbag fits the side of the coal rock sample, which not only fixes the coal rock sample but also seals the end side of the coal rock sample. Compared with the water absorption test device in the related art that cannot seal the side of the coal rock sample, it can reduce and avoid the water injection reagent from being exposed from the side of the coal rock sample, thereby improving the experimental accuracy and more effectively simulating the actual coal rock water absorption process. The coal rock water absorption sample device of the embodiment of the present invention has the advantages of high experimental accuracy.

[0008] In some embodiments, the water injector also has a clamping cavity and a first avoidance port and a second avoidance port connected to the clamping cavity, the clamping cavity and the liquid storage cavity are arranged in the up and down directions, the air bag is arranged in the clamping cavity, the first avoidance port is used to avoid the air nozzle, and the second avoidance port is used to avoid the coal rock sample.

[0009] In some embodiments, the coal rock water absorption experimental device also includes a sealing cover, which has a sealing cavity and a third avoidance port connected to the sealing cavity, the third avoidance port is used to avoid the coal rock sample, and the sealing cover is used to cover the coal rock sample.

[0010] In some embodiments, the frame includes a supporting platform having a supporting surface; the supporting surface is used to support the sealing cover, and the water injector is placed on the sealing cover, or the supporting surface is used to support the water injector, and the sealing cover is placed on the water injector.

[0011] In some embodiments, the liquid storage cavity is arranged below the liquid reservoir so that the water injection reagent in the liquid reservoir automatically flows into the liquid storage cavity.

[0012] In some embodiments, the frame also includes a support rod extending in the up-down direction, the support platform is adjustably arranged on the support rod in the up-down direction, and a scale is provided on the support rod to adjust the height difference between the liquid storage cavity and the liquid reservoir.

[0013] In some embodiments, the coal rock water absorption experimental device includes a forward experimental component and a reverse experimental component, each of the forward experimental component and the reverse experimental component includes the frame, the water injector, the airbag, the liquid reservoir and the sealing cover, the liquid storage chamber in the forward experimental component is arranged on the upper side of the clamping chamber, and the liquid storage chamber in the reverse experimental component is arranged on the lower side of the clamping chamber.

[0014] In some embodiments, the reverse experiment component also includes a supporting frame, the supporting frame having a accommodating cavity and a bypass channel and a fourth bypass port connected to the accommodating cavity, the bypass channel and the fourth bypass port are both used to bypass the water inlet pipe in the reverse experiment component, the supporting frame in the reverse experiment component is placed on the supporting surface, the liquid inlet is arranged corresponding to the fourth bypass port, the water injector is placed on the supporting frame, and the sealing cover is placed on the water injector.

[0015] In some embodiments, the coal rock water absorption experimental device also includes a data acquisition device, which includes an electronic balance and a computer. The electronic balance is connected to the computer signal, and the liquid reservoir is placed on the electronic balance to obtain the weight of the liquid reservoir.

[0016] The coal rock water absorption experimental method of the embodiment of the present invention is implemented using the coal rock water absorption experimental device described in any of the above embodiments, and the coal rock water absorption experimental method includes the following steps: the air bag is set on the coal rock sample and one end face of the coal rock sample is fitted with the water injection surface, and the gas medium is filled into the air bag through the air nozzle to expand the air bag and fit the side of the coal rock sample; the water injection reagent is injected into the liquid reservoir; the liquid inlet is connected with the container mouth, and the liquid storage cavity is filled with the water injection reagent; the end face of the coal rock sample that fits the water injection surface absorbs water, and the water injection reagent is injected into the liquid storage cavity so that the liquid storage cavity is always filled with the water injection reagent, and the weight of the liquid reservoir at any time is obtained.

[0017] The coal rock water absorption experimental method according to the embodiment of the present invention has the advantages of high experimental accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of a coal rock water absorption experimental device according to an embodiment of the present invention.

[0019] Figure 2 yes Figure 1 Schematic diagram of the structure at the forward experimental component.

[0020] Figure 3 yes Figure 2 Schematic diagram of the structure of the liquid storage chamber in the middle water injector.

[0021] Figure 4 yes Figure 2 Schematic diagram of the structure of the clamping cavity in the middle water injector.

[0022] Figure 5 yes Figure 1 Schematic diagram of the structure of the reverse experimental component.

[0023] Reference numerals:

[0024] Coal rock water absorption experimental device 100;

[0025] Frame 1; support base 101; support rod 102; bearing platform 103; bearing surface 1031;

[0026] Water injector 2; liquid storage chamber 201; exhaust port 2011; liquid inlet 2012; water permeable hole 2013; clamping chamber 202; first avoidance port 2021; second avoidance port 2022; side plate 203; first end plate 204; second end plate 205; water injection plate 206; water injection surface 2061;

[0027] Air bag 3; air nozzle 301; nut 302;

[0028] Liquid reservoir 4; container mouth 401;

[0029] Sealing cover 5; Sealing cavity 501; Third avoidance opening 502;

[0030] Carrying frame 6; avoidance passage 601; fourth avoidance opening 602;

[0031] Electronic balance 7;

[0032] Computer 8;

[0033] Coal rock sample 9; water absorption surface 901;

[0034] Water inlet pipe 1001; first control valve 1011; exhaust pipe 1002; second control valve 1021;

[0035] Forward experiment component 10;

[0036] Reverse Experiment Kit 20. DETAILED DESCRIPTION

[0037] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0038] like Figures 1 to 5 As shown, the coal rock water absorption experimental device 100 of the embodiment of the present invention includes a frame 1, an air bag 3, a water injector 2 and a liquid reservoir 4. The air bag 3 is arranged on the frame 1, and the air bag 3 has an air nozzle 301. The air bag 3 is annular and is sleeved on the coal rock sample 9 and fits with the side of the coal rock sample. The water injector 2 is arranged on the frame 1, and the water injector 2 has a water injection surface 2061, a liquid storage cavity 201, and a liquid inlet 2012, an exhaust port 2011 and a water permeable hole 2013 connected to the liquid storage cavity 201. The water injection surface 2061 is used to fit with one end surface of the coal rock sample 9, and the water permeable hole 2013 is arranged on the water injection surface 2061. The liquid reservoir 4 is used to contain water injection reagents, and the liquid reservoir 4 has a container port 401, and the container port 401 is connected to the liquid inlet 2012 through the water inlet pipe 1001.

[0039] When the coal rock water absorption experimental device 100 of the embodiment of the present invention conducts a water absorption experiment on a coal rock sample 9, the airbag 3 is placed on the coal rock sample 9 when the airbag 3 is not filled with gas medium, and one end face of the coal rock sample 9 is made to fit with the water injection surface 2061 of the water injector 2; then, air is filled into the airbag 3 through the air nozzle 301, so that the coal rock sample 9 is clamped and fixed on the frame 1 by the airbag 3, and the side of the coal rock sample 9 is sealed by fitting the airbag 3 with the side of the coal rock sample 9; thereafter, the container mouth 401 is connected to the liquid inlet 2012 through the water inlet pipe 1001, and the water injection reagent in the liquid storage device 4 is injected into the liquid storage chamber 201, and the end face of the coal rock sample 9 that fits with the water injection surface 2061 forms a water absorption surface 901, and the water absorption surface 901 contacts the water injection reagent in the liquid storage chamber 201 through the water permeable hole 2013, thereby achieving single-sided water absorption of the water absorption surface 901 of the coal rock sample 9.

[0040] The coal rock water absorption experimental device 100 of the embodiment of the present invention, by inflating the airbag 3 provided on the frame 1 with gas medium, makes the airbag 3 fit with the side of the coal rock sample 9, not only fixes the coal rock sample 9, but also seals the end side of the coal rock sample 9, thereby achieving single-sided water absorption of the water absorption surface 901 of the coal rock sample 9. Compared with the water absorption experimental device in the related art that cannot seal the side of the coal rock sample, it can reduce and avoid the water injection reagent from being exposed from the side of the coal rock sample, thereby improving the experimental accuracy and more effectively simulating the actual coal rock water absorption process.

[0041] The coal rock water absorption sample device according to the embodiment of the present invention has the advantages of high experimental accuracy.

[0042] Optionally, the airbag 3 is an elastic silicone airbag.

[0043] Optionally, the gas medium filled into the airbag 3 may be air or nitrogen.

[0044] Optionally, a first control valve 1011 is provided on the water inlet pipe 1001 , and the first control valve 1011 is used to control the on-off of the water inlet pipe 1001 , thereby controlling the on-off between the liquid inlet 2012 and the container port 401 .

[0045] In some embodiments, the coal rock water absorption experimental device 100 further includes an electronic balance 7 and a computer 8 , the electronic balance 7 is signal-connected to the computer 8 , and the liquid reservoir 4 is placed on the electronic balance 7 to obtain the weight of the liquid reservoir 4 .

[0046] For example, the electronic balance 7 is connected to the computer 8 via a serial port to dynamically collect the weight change data of the liquid storage container 4 in real time.

[0047] When the coal rock water absorption test device 100 of the embodiment of the present invention performs a water absorption test on a coal rock sample 9, the liquid reservoir 4 storing the water injection reagent is placed on the electronic balance 7; then the liquid reservoir 4 is connected to the liquid storage chamber 201 through the water inlet pipe 1001, and the water injection reagent is filled into the liquid storage chamber 201, and the weight W of the liquid reservoir 4 at this time is weighed by the electronic balance 7. t0 ; Then the water absorption surface 901 of the coal rock sample 9 absorbs water. During the water absorption process of the coal rock sample 9, the water injection reagent is injected into the liquid storage chamber 201 so that the liquid storage chamber 201 is always filled with the water injection reagent. The weight W of the liquid storage chamber 4 at any time can be weighed using an electronic balance ti By calculating, the water absorption of the coal rock sample 9 at any time can be obtained. ti :

[0048] Q ti =W t0 -W ti .

[0049] In addition, the water absorption rate W of the coal rock sample 9 at any time can also be obtained. ti and water absorption rate V ti :

[0050] Wherein, M is the initial mass of the coal rock sample 9, that is, the mass of the coal rock sample 9 in a natural or dry state, and the mass is obtained by weighing the coal rock sample 9 before the experiment.

[0051] Among them, ti is the water absorption time.

[0052] During the water absorption process of the coal-rock sample 9 , the weight data measured by the electronic balance 7 can be transmitted to the computer 8 , and the water absorption curve of the coal-rock sample 9 can be obtained by using the computer 8 .

[0053] By setting up an electronic balance 7 and a computer 8, it is convenient to observe and obtain the water absorption curve of the coal rock sample 9.

[0054] It should be noted that the water injection reagent stored in the liquid reservoir 4 should be greater than a preset amount, which is equal to the capacity of the liquid storage chamber 201 plus the water absorption amount of the coal rock sample 9 when it reaches water absorption saturation, thereby ensuring that the liquid reservoir 4 can continuously provide water injection reagent to the liquid storage chamber 201 before the coal rock sample 9 reaches water absorption saturation.

[0055] In some embodiments, the water injector 2 further has a clamping cavity 202 and a first avoidance port 2021 and a second avoidance port 2022 connected to the clamping cavity 202. The clamping cavity 202 and the liquid storage cavity 201 are arranged in the up-down direction, the air bag 3 is arranged in the clamping cavity 202, the first avoidance port 2021 is used to avoid the air nozzle 301, and the second avoidance port 2022 is used to avoid the coal-rock sample 9.

[0056] For example, Figure 1 , Figure 2 and Figure 5 As shown, the clamping cavity 202 and the liquid storage cavity 201 are arranged in the up-down direction, and the airbag 3 is entirely located in the clamping cavity 202. The air nozzle 301 extends out of the clamping cavity 202 from the first avoidance port 2021 so that the air nozzle 301 is connected to the air pump. The coal rock sample 9 can enter and exit the clamping cavity 202 through the second avoidance port 2022. Specifically, when the coal rock sample 9 needs to be fixed on the frame 1, at least a portion of the coal rock sample 9 is extended into the clamping cavity 202 through the second avoidance port 2022; when the coal rock sample 9 needs to be removed from the frame 1, a portion of the air in the airbag 3 is first released, and then the coal rock sample 9 is taken out of the clamping cavity 202 through the second avoidance port 2022.

[0057] By placing the airbag 3 in the clamping cavity 202, the cavity wall of the clamping cavity 202 can be used to limit the airbag 3 filled with gas medium, and the airbag 3 can be stably fixed on the frame 1, thereby facilitating the fixing of the airbag 3 on the frame 1 and facilitating the assembly of the coal rock water absorption experimental device 100 of the embodiment of the present invention.

[0058] It should be noted that the airbag 3 can enter the clamping cavity 202 through the second avoidance opening 2022 when there is no gas medium or only a part of the gas medium inside, and the air nozzle 301 of the airbag 3 extends out of the clamping cavity 202 through the first avoidance opening 2021.

[0059] Optionally, the coal rock water absorption experimental device 100 includes a nut 302, an air nozzle 301 is provided with an external thread, a part of the air nozzle 301 is located in the second avoidance opening 2022, and another part of the air nozzle 301 extends out of the second avoidance opening 2022. The part of the air nozzle 301 extending out of the second avoidance opening 2022 is threadedly connected to the nut 302, such as Figure 2 and Figure 5 As shown, the portion of the air nozzle 301 located in the avoidance opening is clamped between the air bag 3 and the nut 302 .

[0060] By clamping the portion of the air nozzle 301 located in the avoidance opening between the airbag 3 and the nut 302, the airbag 3 can be prevented from moving relative to the clamping cavity 202 when the gas medium is filled or discharged, thereby achieving stable fixation of the airbag 3 on the water injector 2, which is beneficial to improving the experimental efficiency.

[0061] Optionally, after the airbag 3 is filled with gas medium, the outer peripheral surface of the airbag 3 fits against the side wall of the clamping cavity 202, the upper end surface of the airbag 3 fits against the upper side wall of the clamping cavity 202, and the lower end surface of the airbag 3 fits against the lower side wall of the clamping cavity 202.

[0062] Optionally, the coal rock water absorption experimental device 100 of an embodiment of the present invention includes a forward experimental component 10 and a reverse experimental component 20, each of the forward experimental component 10 and the reverse experimental component 20 includes a frame 1, a water injector 2, an airbag 3 and a liquid reservoir 4, the liquid storage chamber 201 in the forward experimental component 10 is arranged on the upper side of the clamping chamber 202, and the liquid storage chamber 201 in the reverse experimental component 20 is arranged on the lower side of the clamping chamber 202.

[0063] For example, Figure 1 As shown, the forward experiment assembly 10 and the reverse experiment assembly 20 are arranged along the left-right direction, and the forward experiment assembly 10 is arranged on the left side of the reverse experiment assembly 20 .

[0064] It can be understood that positive water absorption means that the water absorption direction of the coal rock sample 9 is consistent with the gravity direction of the water injection reagent, for example, Figure 2 As shown, the liquid storage chamber 201 is located above the coal rock sample 9, and the water absorption direction of the coal rock sample 9 is from top to bottom. Reverse water absorption means that the water absorption direction of the coal rock sample 9 is opposite to the gravity direction of the water injection reagent, for example, Figure 5 As shown, the liquid storage chamber 201 is located below the coal rock sample 9, and the water absorption direction of the coal rock sample 9 is from bottom to top.

[0065] By configuring the coal rock water absorption experimental device 100 to include a forward experimental component 10 and a reverse experimental component 20, the coal rock water absorption experimental device 100 can be used to conduct a forward water absorption experiment on the coal rock sample 9, and the coal rock water absorption experimental device 100 can also be used to conduct a reverse water absorption experiment on the coal rock sample 9.

[0066] Optionally, the water injector 2 includes a side plate 203, a first end plate 204, a second end plate 205 and a water injection plate 206, the side plate 203 is an annular side plate 203, the first end plate 204 and the second end plate 205 are respectively arranged at the two ends of the side plate 203, and the water injection plate 206 is arranged between the first end plate 204 and the second end plate 205. The side plate 203, the first end plate 204 and the water injection plate 206 enclose a liquid storage chamber 201, the liquid inlet 2012 is arranged on the first end plate 204, the water permeable hole 2013 is arranged on the water injection plate 206, and the surface of the water injection plate 206 adjacent to the second end plate 205 forms a water injection surface 2061. The side plate 203, the second end plate 205 and the water injection plate 206 enclose a clamping chamber 202, the first avoidance port 2021 is arranged on the side plate 203, and the second avoidance port 2022 is arranged on the second end plate 205.

[0067] For example, Figure 1 and Figure 2As shown, in the water injector 2 of the forward test assembly 10, the first end plate 204 is arranged above the second end plate 205, the water injection plate is located between the first end plate 204 and the second end plate 205 in the up-down direction, and the water injection plate and the first end plate 204 and the second end plate 205 are arranged at intervals in the up-down direction. The first end plate 204, the water injection plate 206, and the part of the side plate 203 located between the first end plate 204 and the water injection plate 206 form a liquid storage cavity 201, and the lower surface of the water injection plate 206 forms a water injection surface 2061. The second end plate 205, the water injection plate 206, and the part of the side plate 203 located between the second end plate 205 and the water injection plate 206 form a clamping cavity 202.

[0068] For example, Figure 1 and Figure 5 As shown, in the water injector 2 of the reverse test assembly 20, the second end plate 205 is arranged above the first end plate 204, and the water injection plate is located between the first end plate 204 and the second end plate 205 in the up-down direction, and the water injection plate and the first end plate 204 and the second end plate 205 are arranged at intervals in the up-down direction. The first end plate 204, the water injection plate 206, and the part of the side plate 203 located between the first end plate 204 and the water injection plate 206 form a clamping cavity 202. The second end plate 205, the water injection plate 206, and the part of the side plate 203 located between the second end plate 205 and the water injection plate 206 form a liquid storage cavity 201, and the upper surface of the water injection plate 206 forms a water injection surface 2061.

[0069] The water injector 2 has a simple structure and is easy to manufacture.

[0070] Optionally, the side plate 203 , the first end plate 204 , the second end plate 205 and the water injection plate 206 are connected by welding.

[0071] Optionally, a plurality of water permeable holes 2013 are provided.

[0072] For example, Figure 3 As shown, there are five water permeable holes 2013 , one of which is located at the center of the water injection plate, and the other four water permeable holes 2013 are evenly spaced along the circumference of the water injection plate 206 .

[0073] Optionally, the water injection plate 206 has a water injection area and an annular sealing area arranged around the water injection area, the water permeable hole 2013 is arranged in the water injection area, the coal rock sample 9 is arranged corresponding to the water injection area, and the air bag 3 is arranged corresponding to the annular sealing area.

[0074] When the airbag 3 is filled with gas medium, the end surface of the airbag 3 adjacent to the water injection plate 206 is in contact with the annular sealing area, thereby preventing water from seeping out from the side of the coal rock sample 9 closer to the water absorption surface 901, and more effectively providing a single-sided water absorption environment for the coal rock sample 9.

[0075] Optionally, the liquid storage chamber 201 is a sealed chamber 501 , and the exhaust port 2011 is disposed on the first end plate 204 .

[0076] When the water injection reagent is injected into the liquid storage chamber 201, the exhaust port 2011 is opened to discharge the gas in the liquid storage chamber 201, and the liquid storage chamber 201 is filled with the water injection reagent. After the liquid storage chamber 201 is filled with the water injection reagent, the exhaust port 2011 is closed. It should be noted that when the water injection reagent is injected into the liquid storage chamber 201 of the reverse experiment component 20, the water injector 2 can be placed forward first, that is, the water injector 2 is placed in a manner that the liquid storage chamber 201 is located on the upper side of the clamping chamber 202, and the exhaust port 2011 is opened so that the gas in the liquid storage chamber 201 is discharged through the exhaust port 2011.

[0077] Optionally, when conducting a water absorption test on the coal rock sample 9, a portion of the coal rock sample 9 is located in the clamping cavity 202, and another portion of the coal rock sample 9 is located outside the clamping cavity 202, and the airbag 3 is in contact with the side of the portion of the coal rock sample 9 located in the clamping cavity 202.

[0078] For example, the coal rock sample 9 includes a first part and a second part. Figure 1 and 2 As shown, the first part is located on the upper side of the second part, the first part is located in the clamping cavity 202, the second part is located outside the clamping cavity 202, and the airbag 3 is in contact with the side of the first part; or, as shown Figure 1 and 5 As shown, the first part is located at the lower side of the second part, the first part is located outside the clamping cavity 202, the second part is located inside the clamping cavity 202, and the airbag 3 is in contact with the side surface of the first part.

[0079] When conducting a water absorption experiment on the coal rock sample 9, the position of the coal rock sample 9 can be adjusted by holding the second part of the coal rock sample 9, thereby facilitating fixing the coal rock sample 9 on the water injector 2 and removing the coal rock sample 9 from the water injector 2.

[0080] Of course, in other embodiments, the coal rock sample 9 may also be located entirely in the clamping cavity 202 .

[0081] In some embodiments, the coal rock water absorption experimental device 100 also includes a sealing cover 5, which has a sealing cavity 501 and a third avoidance port 502 connected to the sealing cavity 501, the third avoidance port 502 is used to avoid the coal rock sample 9, and the sealing cover 5 is used to cover the coal rock sample 9.

[0082] For example, Figure 1 , Figure 2 and Figure 5 As shown, the second part of the coal rock sample 9 is located outside the clamping cavity 202 , and the sealing cover 5 is provided on the second part of the coal rock sample 9 .

[0083] By placing the sealing cover 5 on the coal rock sample 9, the surface of the coal rock sample 9 that can contact the external environment (excluding the water absorption surface 901 and the side that is in contact with the airbag 3) is located in the sealing cavity 501 of the sealing cover 5, which can effectively reduce the contact between the surface of the coal rock sample 9 and the external environment, thereby reducing the evaporation of the water injection reagent on the coal rock sample 9, and further reducing the experimental error and improving the experimental accuracy.

[0084] In some embodiments, the frame 1 includes a support platform 103, and the support platform 103 has a support surface 1031. In the forward experimental assembly 10, the support surface 1031 is used to support the sealing cover 5, and the water injector 2 is placed on the sealing cover 5. In the reverse experimental assembly 20, the support surface 1031 is used to support the water injector 2, and the sealing cover 5 is placed on the water injector 2.

[0085] For example, Figure 1 and Figure 2 As shown, the sealing cover 5 is placed on the bearing surface 1031, and the water injector 2 is placed on the sealing cover 5, and the bearing surface 1031 is used to support the sealing cover 5 and the water injector 2. Figure 1 and Figure 5 As shown, the sealing cover 5 is placed on the water injector 2 , and the water injector 2 is supported by the bearing surface 1031 .

[0086] By setting a bearing surface 1031 on the frame 1, the bearing surface 1031 is used to support the sealing cover 5 or the water injector 2, and the sealing cover 5 is used to support the water injector 2, or the water injector 2 is used to support the sealing cover 5. When conducting a coal-rock water absorption experiment, it is only necessary to place the sealing cover 5 and the water injector 2 on the bearing platform 103 in an upper and lower order, and there is no need to connect the water injector 2 with the frame 1 and the sealing cover 5 with the frame 1, thereby further facilitating the assembly of the coal-rock water absorption experiment device 100.

[0087] Optionally, in the forward test assembly 10 , the sealing cover 5 is connected to the supporting platform 103 via a first fastener.

[0088] For example, in the forward test assembly 10, the sealing cover 5 is provided with a first connection hole, the support platform 103 is provided with a second connection hole, and the first fastener is inserted into the first connection hole and the second connection hole to achieve the connection between the sealing cover 5 and the support platform 103. The first fastener can be a latch, a screw, etc.

[0089] The sealing cover 5 is connected to the bearing platform 103 by a first fastener, which can improve the connection stability between the sealing cover 5 and the frame 1. Optionally, the reverse experiment assembly 20 also includes a bearing frame 6, the bearing frame 6 has a receiving cavity and an avoidance channel 601 and a fourth avoidance port 602 connected to the receiving cavity, and the avoidance channel 601 and the fourth avoidance port 602 are both used to avoid the water inlet pipe 1001 in the reverse experiment assembly 20. In the reverse experiment assembly 20, the bearing frame 6 is placed on the bearing surface 1031, the liquid inlet 2012 is arranged corresponding to the fourth avoidance port 602, the water injector 2 is placed on the bearing frame 6, and the sealing cover 5 is placed on the water injector 2.

[0090] For example, Figure 1 and Figure 5 As shown, the sealing cover 5 is placed on the water injector 2, the water injector 2 is placed on the support frame 6, and the support frame 6 is placed on the support surface 1031, so that the support frame 6, the water injector 2 and the sealing cover 5 are supported by the support platform 103. The support frame 6 is provided with an avoidance channel 601 and a fourth avoidance port 602 connected to the accommodating cavity, so that the water inlet pipe 1001 of the reverse experiment assembly 20 can pass through the avoidance channel 601 and the fourth avoidance port 602, and a part of the water inlet pipe 1001 is located in the accommodating cavity of the support frame 6.

[0091] By setting up a supporting frame 6, and setting an avoidance channel 601 and a fourth avoidance port 602 for avoiding the water inlet pipe 1001 on the supporting frame 6, when conducting a coal rock water absorption experiment, it is only necessary to place the sealing cover 5, the water injector 2 and the supporting frame 6 in an upper and lower order on the supporting platform 103, thereby further facilitating the assembly of the coal rock water absorption experiment device 100.

[0092] Optionally, the exhaust port 2011 of the reverse experiment component 20 is connected to an exhaust pipe 1002 , the fourth avoidance port 602 is also used to avoid the exhaust pipe 1002 of the reverse experiment component 20 , and a portion of the exhaust pipe 1002 is located in the accommodating cavity of the carrier 6 .

[0093] Optionally, the support frame 6 is a support tube with one end open, the tube wall of the support tube is open, the open end of the support tube forms a fourth avoidance opening 602, and the opening on the tube wall forms an avoidance channel 601.

[0094] Optionally, in the reverse test assembly 20 , the support frame 6 is connected to the support platform 103 via a second fastener.

[0095] For example, in the reverse experiment assembly 20, the support frame 6 is provided with a third connection hole, the support platform 103 is provided with a fourth connection hole, and the second fastener is inserted into the third connection hole and the fourth connection hole to achieve the connection between the support frame 6 and the support platform 103. The second fastener can be a latch, a screw, etc.

[0096] The supporting frame 6 is connected to the supporting platform 103 via a second fastener, which can improve the connection stability between the supporting frame 6 and the frame body 1 .

[0097] Optionally, a second control valve 1021 is provided on the exhaust pipe 1002 , and the second control valve 1021 is used to control the on-off of the exhaust pipe 1002 , thereby controlling the on-off of the exhaust port 2011 .

[0098] Optionally, the liquid storage chamber 201 is arranged below the liquid reservoir 4 so that the water injection reagent in the liquid reservoir 4 automatically flows into the liquid storage chamber 201 .

[0099] For example, Figure 1 , Figure 2 and Figure 5 As shown, the liquid reservoir 4 is located above the liquid storage cavity 201, and the water injection reagent in the liquid reservoir 4 can automatically flow into the liquid storage cavity 201 under the action of gravity.

[0100] By setting the positions of the liquid storage chamber 201 and the liquid storage device 4, the water injection reagent in the liquid storage device 4 can automatically flow into the liquid storage chamber 201, avoiding the need to set a driving pump for pumping the water injection reagent between the liquid storage chamber 4 and the liquid storage chamber 201. This can simplify the structure of the coal rock water absorption experimental device 100 and save experimental costs.

[0101] Optionally, the frame 1 further includes a support rod 102 extending in the up-down direction, and the support platform 103 is arranged on the support rod 102 in an adjustable manner in the up-down direction so as to adjust the height difference between the liquid storage cavity 201 and the liquid reservoir 4 .

[0102] By moving the supporting platform 103 in the up and down directions, the height difference between the liquid storage chamber 201 and the liquid storage container 4 can be adjusted, thereby adjusting the pressure difference between the liquid inlet 2012 and the container mouth 401, providing different head pressures for the coal rock sample 9 to absorb water, thereby realizing the water absorption experiment of the coal rock sample under different head pressures.

[0103] Optionally, a clamp is provided on the supporting platform 103 , and the position of the clamp is adjustable along the up-down direction and connected to the supporting rod 102 .

[0104] Optionally, the clamp includes a fixed arm and a movable arm, the support rod 102 is clamped and fixed between the fixed arm and the movable arm, and the fixed arm and the movable arm are tightened by a screw and a nut 302 .

[0105] Optionally, the moving range of the carrying platform 103 is 0 to 1 m.

[0106] Optionally, the support rod 102 is provided with a scale.

[0107] By setting a scale on the support rod 102, the position of the support platform 103 can be intuitively observed according to the scale on the support rod 102, so as to conveniently obtain the height difference between the liquid storage cavity 201 and the liquid reservoir 4, and then obtain the pressure difference between the liquid inlet 2012 and the container mouth 401.

[0108] Optionally, the frame 1 further includes a support base 101 , and a support rod 102 is disposed on the support base 101 .

[0109] Optionally, the support base 101 is a support plate.

[0110] Optionally, the sealing cover 5 is a transparent sealing cover.

[0111] When the forward water absorption test of the coal rock sample 9 is carried out using the forward experimental assembly 10, observe through the sealing cover 5 whether there is water injection reagent flowing out of the bottom surface of the coal rock sample 9. When water injection reagent flows out of the bottom surface of the coal rock sample 9, the coal rock experiment reaches water absorption saturation and the experiment can be stopped.

[0112] By setting the sealing cover 5 as a transparent sealing cover, it is convenient to observe whether the coal rock sample 9 has reached water absorption saturation, which is beneficial to improving the experimental efficiency.

[0113] Optionally, the sealing cover 5 is made of transparent materials such as acrylic and glass.

[0114] It can be understood that when the reverse water absorption test of the coal rock sample 9 is performed using the reverse test assembly 20, by observing the water absorption curve displayed in the calculation, when the water absorption curve trend is flat (the water absorption quality remains unchanged), the coal rock test reaches water absorption saturation and the test can be stopped. Figures 1 to 5 The coal rock water absorption test method according to the embodiment of the present invention is described. The coal rock water absorption test method according to the embodiment of the present invention is implemented by using the coal rock water absorption test device 100 described in any of the above embodiments. The coal rock water absorption test method according to the embodiment of the present invention includes the following steps:

[0115] The airbag 3 is sleeved on the coal rock sample 9 and one end surface of the coal rock sample 9 is made to fit with the water injection surface 2061. The air medium is filled into the airbag 3 through the air nozzle 301 to expand the airbag 3 and fit with the side of the coal rock sample 9, so as to fix the coal rock sample 9 on the frame 1 and seal the side of the coal rock sample 9.

[0116] Injecting water injection reagent into the reservoir 4;

[0117] Connect the liquid inlet 2012 to the container port 401 and fill the liquid storage chamber 201 with the water injection reagent;

[0118] The end face of the coal rock sample 9 that is in contact with the water injection surface 2061 absorbs water, and the water injection reagent is injected into the liquid storage chamber 201 so that the liquid storage chamber 201 is always filled with the water injection reagent, and the weight of the liquid storage container 4 at any time is obtained.

[0119] For example, Figure 1 and Figure 2 As shown, when the forward water absorption experiment is carried out on the coal rock sample: the airbag 3 is installed in the clamping cavity 202, the air nozzle 301 of the airbag 3 passes through the first avoidance port 2021, and a nut 302 is installed on the air nozzle 301 to fix the airbag 3; the coal rock sample 9 is inserted into the airbag 3, and the airbag 3 is inflated with a gas medium (such as nitrogen) through an air pump. After the airbag 3 is inflated, the coal rock sample 9 is clamped to achieve the fixation of the coal rock sample 9 and the sealing of the side of the coal rock sample 9, so as to prevent water from seeping out from the side of the coal rock sample 9 closer to the water injection surface 2061, and provide a single-sided water absorption environment for the coal rock sample 9; after the coal rock sample 9 is installed, the water injector 2 with the coal rock sample 9 fixed is placed on the sealing cover 5 to reduce the water vaporization. Experimental errors caused by the occurrence of the problem; the sealing cover 5 together with the water injector 2 are placed on a supporting platform 103 with a preset height for fixing; the liquid storage chamber 201 is connected to the liquid storage device 4 through the water inlet pipe 1001, and the liquid storage chamber 201 is filled with water injection reagent, and the second control valve 1021 is opened. After water enters the liquid storage chamber 201 through the liquid inlet 2012, it contacts the coal rock sample 9 through the water permeable hole 2013 between the liquid storage chamber 201 and the clamping chamber 202. After the liquid storage chamber 201 is filled, the exhaust port 2011 is closed, and the data acquisition device is immediately turned on for data acquisition; during the experiment, observe whether there is water droplets overflowing from the lower end surface of the coal rock sample 9. If so, the experiment should be stopped immediately, and the coal rock sample 9 is saturated with water.

[0120] like Figure 1 and Figure 5As shown, when the reverse water absorption experiment is carried out on the coal rock sample: the airbag 3 is installed in the clamping cavity 202, the air nozzle 301 of the airbag 3 passes through the first avoidance port 2021, and a nut 302 is installed on the air nozzle 301 to fix the airbag 3; the coal rock sample 9 is inserted into the airbag 3, and the airbag 3 is inflated with a gas medium (such as nitrogen) through an air pump. After the airbag 3 is inflated, the coal rock sample 9 is clamped to fix the coal rock sample 9 and seal the side of the coal rock sample, thereby preventing water from seeping out from the side of the coal rock sample 9 closer to the water injection surface 2061, and providing a single-sided water absorption environment for the coal rock sample 9; the liquid storage cavity 201 is connected to the liquid reservoir 4 through the water inlet pipe 1001, and the liquid storage cavity 201 is filled with water injection reagent, and the second control is opened. Valve 1021 is controlled. After water enters the liquid storage chamber 201 through the liquid inlet 2012, it contacts the coal rock sample 9 through the water permeable hole 2013 between the liquid storage chamber 201 and the clamping chamber 202. After the liquid storage chamber 201 is filled, the exhaust port 2011 is closed; the first control valve 1011 is closed, and the water injector 2 is placed upside down on the support frame 6, and the sealing cover 5 is covered on the water injector 2 to reduce the experimental error caused by water evaporation; the sealing cover 5, the water injector 2 and the support frame 6 are placed together on the support platform 103 with a preset height for fixation, and the data acquisition device is immediately turned on for data acquisition. During the experiment, the water absorption curve displayed on the computer 8 is observed. After the curve trends smoothly, the experiment is stopped and the sample is saturated with water.

[0121] The coal rock water absorption experimental device 100 of the embodiment of the present invention adopts the air bag 3 to clamp and fix the coal rock sample 9, and realizes the watertight sealing of the coal rock sample 9, provides a single-sided water absorption environment for the coal rock sample 9, and has good air tightness, and the clamping and loading and unloading operations of the coal rock sample 9 are relatively convenient; and after the air bag 3 clamps and seals the coal rock sample 9, no matter it is a forward water absorption experiment or a reverse water absorption experiment, the liquid storage chamber 201 can be kept full of water, thereby ensuring that during the water absorption process of the coal rock sample 9, the contact area between the coal rock sample 9 and water remains unchanged, reducing the experimental error.

[0122] The coal rock water absorption experimental device and experimental method of the embodiment of the present invention can similarly simulate the forward and reverse seepage water absorption process of coal rock during coal seam water injection, characterize the seepage water absorption law of coal rock samples under different head pressures and water injection reagents, and provide a basis for determining the injection process parameters of coal seam water injection.

[0123] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0124] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0125] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0126] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0127] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0128] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments by those of ordinary skill in the art are all within the scope of protection of the present invention.

Claims

1. A coal rock water absorption experimental device, characterized in that: include: Frame; An airbag, the airbag is arranged on the frame, the airbag is annular and is sleeved on the coal rock sample and fits the side of the coal rock sample, and the airbag has an air nozzle; A water injector, the water injector is arranged on the frame, the water injector has a water injection surface, a liquid storage cavity, and a liquid inlet, an exhaust port and a water permeable hole connected to the liquid storage cavity, the water injection surface is used to fit with the end surface of the coal rock sample, and the water permeable hole is arranged on the water injection surface; as well as A liquid reservoir, the liquid reservoir is used to contain the water injection reagent, the liquid reservoir has a container port, and the container port is connected to the liquid inlet through a water inlet pipe; The water injector also has a clamping cavity and a first avoidance port and a second avoidance port connected to the clamping cavity, the clamping cavity and the liquid storage cavity are arranged in the up-down direction, the air bag is arranged in the clamping cavity, the first avoidance port is used to avoid the air nozzle, and the second avoidance port is used to avoid the coal-rock sample; The coal-rock water absorption experimental device comprises a forward experimental component and a reverse experimental component, each of which comprises the frame, the water injector, the air bag, the liquid reservoir and a sealing cover, the liquid storage chamber in the forward experimental component is arranged on the upper side of the clamping chamber, and the liquid storage chamber in the reverse experimental component is arranged on the lower side of the clamping chamber; The coal rock water absorption experimental device also includes a data acquisition device, which includes an electronic balance and a computer. The electronic balance is connected to the computer signal, and the liquid reservoir is placed on the electronic balance to obtain the weight of the liquid reservoir.

2. The coal rock water absorption experimental device according to claim 1 is characterized in that: The coal rock water absorption experimental device also includes a sealing cover, which has a sealing cavity and a third avoidance port connected to the sealing cavity, the third avoidance port is used to avoid the coal rock sample, and the sealing cover is used to cover the coal rock sample.

3. The coal rock water absorption experimental device according to claim 2 is characterized in that: The frame includes a bearing platform, and the bearing platform has a bearing surface; The bearing surface is used to support the sealing cover, and the water injector is placed on the sealing cover, or The bearing surface is used to support the water injector, and the sealing cover is placed on the water injector.

4. The coal rock water absorption experimental device according to claim 3 is characterized in that: The liquid storage cavity is arranged below the liquid reservoir so that the water injection reagent in the liquid reservoir automatically flows into the liquid storage cavity.

5. The coal rock water absorption experimental device according to claim 4 is characterized in that: The frame also includes a support rod extending in the up-down direction, the support rod is provided with a scale, and the support platform is adjustably arranged on the support rod in the up-down direction so as to adjust the height difference between the liquid storage cavity and the liquid reservoir.

6. The coal rock water absorption experimental device according to claim 5, characterized in that: The reverse experiment component also includes a supporting frame, which has a accommodating cavity and an avoidance channel and a fourth avoidance port connected to the accommodating cavity. The avoidance channel and the fourth avoidance port are both used to avoid the water inlet pipe in the reverse experiment component. The supporting frame in the reverse experiment component is placed on the supporting surface, the liquid inlet is arranged corresponding to the fourth avoidance port, the water injector is placed on the supporting frame, and the sealing cover is placed on the water injector.

7. A coal rock water absorption test method, characterized in that: The coal rock water absorption experimental method is implemented using the coal rock water absorption experimental device described in any one of claims 1 to 6, and the coal rock water absorption experimental method comprises the following steps: The air bag is placed on the coal rock sample so that one end surface of the coal rock sample is in contact with the water injection surface, and a gas medium is filled into the air bag through the air nozzle to expand the air bag and make it in contact with the side surface of the coal rock sample; injecting a water injection reagent into the reservoir; Connect the liquid inlet to the container port, and fill the liquid storage cavity with water injection reagent; The end face of the coal rock sample in contact with the water injection surface absorbs water, and the water injection reagent is injected into the liquid storage cavity so that the liquid storage cavity is always filled with the water injection reagent, and the weight of the liquid storage device at any time is obtained.

Images