A physical simulation device for mechanical deslagging extraction drilling hole grouting sealing process

Abstract

The utility model belongs to the technical field of analog gas extraction, specifically relates to a kind of mechanical deslagging extraction drilling grouting hole sealing process physical simulation device.The device includes box, filler, support tube, first bag seal hole device, second bag seal hole device, first grouting pipe, grouting pump and extraction pipe.The device can realize the laboratory simulation of the whole process of underground gas extraction drilling sealing process, and different drilling aperture, different drilling inclination, different hole sealing process drilling grouting hole sealing test can be carried out in detail.In the test process, the pressure-bearing capacity and sealing effect of the bag seal hole device can be effectively evaluated, and the stability and optimized blasting pressure of the blasting valve can be tested.In addition, the device simulates the cutting face observation of coal seam after a certain time of grouting hole sealing, realizes the visual representation of slurry diffusion and penetration capacity, and further provides data support for the optimization of drilling sealing material.

Description

Technical Field

[0001] This utility model belongs to the field of simulated gas extraction technology, specifically relating to a physical simulation device for the mechanical slag removal, extraction, drilling, grouting, and sealing process. Background Technology

[0002] Borehole gas drainage is a key measure for effectively reducing coal seam gas content and preventing coal and gas outburst accidents in high-gas and outburst-prone mines in my country. Continuously optimizing borehole sealing technology and materials based on the actual conditions and needs of underground gas drainage in coal mines is a crucial step in effectively improving borehole sealing quality, increasing gas drainage concentration, and ensuring that coal seam gas drainage meets standards. Currently, many mines use a "two-plug-one-injection" sealing process, where a bag-type sealing device is used as the plug and grout is injected in the middle. During sealing, grout needs to be injected into the bag and maintained at a certain pressure to expand and adhere to the borehole wall, thus sealing the borehole and ensuring effective pressurized grouting in the middle section. Therefore, the tightness of the fit between the bag-type sealing device and the borehole wall is one of the keys to ensuring effective radial penetration and diffusion of grout into the surrounding rock fissures during pressurized grouting, guaranteeing a high-quality seal. Simultaneously, the range of radial penetration and diffusion of grout along the borehole is also crucial for effectively sealing gas leakage channels such as surrounding rock fissures.

[0003] Currently, coal mines primarily employ two methods for drilling gas extraction boreholes: hydraulic and mechanical cuttings removal. Both methods efficiently remove drill cuttings. However, because the borehole wall of mechanically removed boreholes is not perfectly smooth, it is more prone to leaving fine drill cuttings on the borehole wall compared to hydraulic cuttings removal, increasing the specific surface area of ​​the borehole wall interface. The drill cuttings remaining on the borehole wall surface form an "isolation layer" between the bag sealer and the coal wall, causing a false fit between the bag sealer and the coal wall. The gaps between drill cutting particles connect with micro-fractures in the coal body, forming hidden and tiny gas leakage channels. As the extraction time increases, the leakage effect caused by these tiny channels gradually amplifies, thus affecting the final extraction effect. Furthermore, during grouting, the mixing of coal powder reduces the wettability of the grout at the coal interface, leading to decreased grout fluidity after the addition of coal powder particles. This results in a smaller grout penetration radius, weakening the sealing depth of the borehole surrounding rock fractures during pressurized grouting and reducing the sealing quality.

[0004] To improve the quality of grouting and sealing in mechanically discharged boreholes, it is necessary to optimize the grouting materials and processes, and verify the sealing effect through experiments. Currently, most tests on gas drainage boreholes and grouting sealing are conducted in the underground field, with few preliminary simulations and verifications performed in surface laboratories. Considering the high manpower and material costs of underground tests and the inability to guarantee the achievement of target test results; furthermore, the high cost of underground pre-drainage borehole construction, coupled with poor test results, wastes the underground borehole and affects the actual overall pre-drainage effect. Therefore, it is necessary to design a physical simulation device for the grouting and sealing process in mechanically discharged boreholes to clarify the specific influence characteristics of coal powder on bag sealing and grout diffusion characteristics, providing reliable data support and experimental basis for continuous improvement and optimization of borehole sealing technology. Utility Model Content

[0005] The purpose of this invention is to provide a physical simulation device for the grouting and sealing process of mechanical slag removal drilling, so as to simulate the grouting and sealing process of underground gas extraction drilling and realize the visual characterization of slurry diffusion and permeability.

[0006] To achieve the above objectives, this utility model provides the following technical solution: A physical simulation device for the mechanical slag removal, extraction, drilling, grouting, and sealing process includes: Box; The filling material, placed inside the box, is used to simulate a coal seam; The support tube, made of transparent material, is placed inside the filler. The support tube is used to simulate drilling, and multiple permeation slits are provided on the tube wall. In particular, multiple sets of simulated fractures are provided in the filler along the axial direction of the support tube. The first bag sealing device is located at the inner end of the support tube; The second bag sealing device is located at the outer end of the support tube; The first grouting pipe is connected in sequence to the first bag sealer and the second bag sealer, and a burst valve is provided on the first grouting pipe at the position between the first bag sealer and the second bag sealer. The grouting pump has a grout output pipeline that can be connected to the first grouting pipe; The extraction tube is installed inside the support tube and passes through the second bag sealer and the first bag sealer in sequence.

[0007] Furthermore, the enclosure includes an enclosure body and an end cap, which are connected by bolts.

[0008] Furthermore, lifting frames are provided at both ends of the bottom of the box, with the telescopic ends of the lifting frames connected to the box and the fixed ends of the lifting frames located on the ground.

[0009] Furthermore, the filler is made from granular coal, cement, water, and kerosene in a set ratio.

[0010] Furthermore, the support tube is made of plexiglass.

[0011] Furthermore, each permeation slit on the wall of the support pipe is elongated and extends along the axial direction of the support pipe.

[0012] Furthermore, each set of simulated cracks includes multiple simulated cracks, which are arranged to extend radially along the support tube.

[0013] Furthermore, the slurry output pipeline is connected to the first grouting pipe via a quick connector.

[0014] Furthermore, a pressure gauge is installed on the slurry output pipeline.

[0015] Furthermore, it also includes a second grouting pipe; One end of the second grouting pipe is located between the first bag sealer and the second bag sealer, and a one-way valve is provided at one end of the second grouting pipe. The other end of the second grouting pipe leads to the outside of the box body, and the grout output pipeline can be connected to the other end of the second grouting pipe.

[0016] Compared with the prior art, this utility model has the following advantages: (1) This device can realize laboratory simulation of the entire process of borehole sealing technology for underground gas extraction. Specifically, it can carry out borehole grouting and sealing tests with different borehole diameters, different borehole inclinations, and different sealing technologies. During the test, the pressure-bearing capacity and sealing effect of the bag sealer can be effectively evaluated, and the stability of the rupture valve can be tested and the rupture pressure optimized.

[0017] (2) This device can realize the process of grouting with pressure for sealing boreholes. By observing the cutting surface of the simulated coal seam after grouting and sealing the borehole for a certain period of time, it can intuitively characterize the consolidation state, penetration radius, and bonding state with the fracture wall of different borehole sealing materials. This enables laboratory evaluation of the specific performance of borehole sealing materials, such as actual permeability, bonding strength, durability and self-adaptability, and provides data support for the optimization of borehole sealing materials.

[0018] (3) The device can carry out pressurized secondary grouting or secondary grouting in the laboratory through the second grouting pipe, obtain the sealing effect of the grout on the surrounding rock fissures of the borehole after secondary grouting or secondary grouting, realize the feasibility test of improving the sealing effect of secondary grouting or secondary grouting, and provide strong support for the optimization of borehole sealing technology. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0020] Figure 1 This is a schematic diagram of a physical simulation device for the mechanical slag removal, extraction, drilling, grouting, and sealing process of this utility model. Figure 2 This is a schematic diagram of the support pipe in a physical simulation device for the mechanical slag removal, extraction, drilling, grouting, and sealing process of this utility model. Figure 3 This is a schematic diagram of a simulated fracture in a physical simulation device for the mechanical slag removal, extraction, drilling, grouting, and sealing process of this utility model.

[0021] Explanation of reference numerals in the attached drawings: 1-box body, 11-bolt, 12-lifting frame, 2-filler, 21-simulated fracture, 3-support pipe, 31-permeable fissure, 4-first bag sealer, 5-second bag sealer, 6-first grouting pipe, 61-bursting valve, 62-quick connector, 7-grouting pump, 71-pressure gauge, 8-extraction pipe, 9-second grouting pipe, 91-check valve. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0023] like Figure 1 As shown, a physical simulation device for the mechanical slag removal, extraction, drilling, grouting, and sealing process includes a box 1, a filler 2, a support pipe 3, a first bag sealer 4, a second bag sealer 5, a first grouting pipe 6, a grouting pump 7, and an extraction pipe 8.

[0024] The housing 1 is made of high-strength plexiglass and forms a cavity for creating a simulated coal seam. The housing 1 includes a main body and end caps, which are connected by bolts 11. Lifting frames 12 are installed at both ends of the bottom of the housing 1. The telescopic ends of the lifting frames 12 are connected to the housing 1, and the fixed ends are connected to the ground. The height of the lifting frames 12 allows for changes in the inclination angle of the simulated coal seam and simulated borehole.

[0025] The filler 2 is placed inside the housing 1. The filler 2 is used to simulate a coal seam and is made of granular coal, cement, water and kerosene in a set ratio. In this embodiment, the filler 2 is made of granular coal, cement, water and kerosene in a ratio of 4:2:1:1, which can maximize the reproduction of the coal seam and solve the shortcomings of loose coal powder raw materials, difficulty in consolidation and weak strength.

[0026] like Figure 2 As shown, the support tube 3 is disposed inside the filler 2. The support tube 3 is used to simulate drilling and is made of high-strength plexiglass. Both ends of the support tube 3 are open. Multiple permeation slits 31 are arranged circumferentially at the same position on the middle wall of the support tube 3. Each permeation slit 31 is elongated and extends along the axial direction of the support tube 3. Furthermore, as... Figure 1 and Figure 3 As shown, multiple sets of simulated cracks 21 are arranged along the axial direction of the support tube 3 in the filler 2. Each set of simulated cracks 21 contains multiple simulated cracks 21; in this embodiment, each set of simulated cracks 21 contains eight simulated cracks 21. The multiple simulated cracks 21 are arranged radially along the support tube 3, i.e., the multiple simulated cracks 21 are arranged radially. One end of each simulated crack 21 extends to the support tube 3, and the other end of each simulated crack 21 extends to the housing 1.

[0027] The first grouting bag sealer 4 is located at the inner end of the support pipe 3, and the second grouting bag sealer 5 is located at the outer end of the support pipe 3. The first grouting pipe 6 connects the first grouting bag sealer 4 and the second grouting bag sealer 5 in sequence. A burst valve 61 is installed on the section of the first grouting pipe 6 between the first grouting bag sealer 4 and the second grouting bag sealer 5. Two burst valves 61 are installed, one close to the first grouting bag sealer 4 and the other close to the second grouting bag sealer 5. This arrangement takes into account the inclined design of the simulated coal seam and the simulated borehole, ensuring that at least one burst valve 61 will be destroyed first during grouting. The slurry output pipeline of the grouting pump 7 is connected to the first grouting pipe 6 via a quick connector 62. A pressure gauge 71 is installed on the slurry output pipeline to monitor the pressure of the slurry output by the grouting pump 7 and the pressure when the burst valve 61 bursts in real time. The extraction pipe 8 is located inside the support pipe 3, and the extraction pipe 8 passes through the second grouting bag sealer 5 and the first grouting bag sealer 4 in sequence. The extraction tube 8 can be sealed to the first bag sealer 4 and the second bag sealer 5 respectively.

[0028] This physical simulation device also includes a second grouting pipe 9, which serves as a backup grouting pipe. One end of the second grouting pipe 9 is positioned between the first bag sealer 4 and the second bag sealer 5, and a one-way valve 91 is installed at one end of the second grouting pipe 9. The other end of the second grouting pipe 9 passes through the second bag sealer 5 and leads to the outside of the housing 1, and the grout output pipeline of the grouting pump 7 can be connected to the other end of the second grouting pipe 9 via a quick connector 62.

[0029] The physical simulation device in this embodiment operates as follows: The physical simulation device is constructed as follows: First, before creating the simulated coal seam, the support pipe 3 used for creating the simulated borehole is inserted into the box 1. Then, a filler 2 made of granular coal, cement, water, and kerosene is injected into the box 1. The gaps 31 on the support pipe 3 are very small, preventing the filler 2 from flowing into the support pipe 3 through the gaps 31. Finally, after the filler 2 has completely solidified to form the simulated coal seam, multiple sets of simulated fractures 21 are drilled from the simulated coal seam along the axial direction of the support pipe 3 using a drilling tool. The number of sets of simulated fractures 21 depends on the actual situation, such as the length of the support pipe 3. During the drilling process, irregular multi-scale fractures will also be generated in the simulated coal seam due to mechanical disturbance, thus forming a complete fracture network with the simulated fractures 21, maximizing the reproduction of the fracture network state of the underground coal seam.

[0030] The borehole sealing process test is divided into a sealing stage and a grouting stage. In the sealing stage, the first grouting pipe 6 is sequentially connected to the second bag sealer 5 and the first bag sealer 4, and inserted into the support pipe 3, so that multiple simulated fractures 21 are located between the first bag sealer 4 and the second bag sealer 5. The grouting pump 7 is connected to the first grouting pipe 6. In the grouting stage, the borehole sealing material is first mixed with water in a certain proportion to form a grout. The grout is then injected into the first bag sealer 4 and the second bag sealer 5 through the grouting pump 7 and the first grouting pipe 6. When the grout fills the first bag sealer 4 and the second bag sealer 5, both the first bag sealer 4 and the second bag sealer 5 are tightly fitted against the inner wall of the support pipe 3. As grouting continues, pressure gauge 71 is monitored. When pressure gauge 71 suddenly drops to zero, it indicates that at least one burst valve 61 has ruptured. The maximum pressure at this point is the burst pressure of the burst valve 61. Grout then begins to be injected from the rupture point of the burst valve 61 into the area between the first and second bag sealers 4 and 5 within the support pipe 3. Grout permeation gaps 31 are provided on the wall of the support pipe 3, allowing grout to enter the simulated fracture 21. As the grout gradually fills the area between the first and second bag sealers 4 and 5 within the support pipe 3, and the simulated fracture 21 in the simulated coal seam, the grout pressure gradually increases, achieving pressurized grouting.

[0031] The performance of the bag sealer can be effectively monitored and tested during the grouting process, such as its pressure-bearing capacity and sealing effect. Furthermore, the stability of the rupture valve 61 can be verified, and the rupture pressure optimized. After the grout has completely solidified in the physical simulation device, the box 1 can be removed by unscrewing the bolts 11 used to fix it. The simulated coal seam block is cut along an arbitrary cross-section using a cutting machine, and the penetration radius and fracture filling effect of the grout under a certain grouting pressure are observed. Based on the experimental results, reasonable grouting parameters can be determined. The actual permeability, bonding strength, durability, and self-adaptive ability of the borehole sealing material can also be evaluated based on the test samples after cutting. In addition, the second grouting pipe 9 can continue pressurized grouting when the first grouting pipe 6 fails, and can also be connected to the grout output pipeline of the grouting pump 7 via a quick connector 62 after a period of time following borehole sealing for supplementary grouting, achieving secondary grouting.

[0032] The present embodiment has now been described in detail with reference to the accompanying drawings. Based on the above description, those skilled in the art should have a clear understanding of the present invention. Of course, the above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the content of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention and should be protected by the present invention.

Claims

1. A physical simulation device for the mechanical slag removal, extraction, drilling, grouting, and sealing process, characterized in that, include: Box; The filling material, placed inside the box, is used to simulate a coal seam; The support tube, made of transparent material, is placed inside the filler. The support tube is used to simulate drilling, and multiple permeation slits are provided on the tube wall. In particular, multiple sets of simulated fractures are provided in the filler along the axial direction of the support tube. The first bag sealing device is located at the inner end of the support tube; The second bag sealing device is located at the outer end of the support tube; The first grouting pipe is connected in sequence to the first bag sealer and the second bag sealer, and a burst valve is provided on the first grouting pipe at the position between the first bag sealer and the second bag sealer. The grouting pump has a grout output pipeline that can be connected to the first grouting pipe; The extraction tube is installed inside the support tube and passes through the second bag sealer and the first bag sealer in sequence.

2. The physical simulation device for mechanical slag removal, extraction, drilling, grouting, and sealing process according to claim 1, characterized in that, The enclosure includes a main body and end caps, which are connected by bolts.

3. The physical simulation device for mechanical slag removal, extraction, drilling, grouting, and sealing process according to claim 1, characterized in that, Both ends of the bottom of the box are equipped with lifting frames. The telescopic ends of the lifting frames are connected to the box, and the fixed ends of the lifting frames are set on the ground.

4. The physical simulation device for mechanical slag removal, extraction, drilling, grouting, and sealing process according to claim 1, characterized in that, The filler is made from granular coal, cement, water, and kerosene in a set ratio.

5. The physical simulation device for mechanical slag removal, extraction, drilling, grouting, and sealing process according to claim 1, characterized in that, The support tube is made of plexiglass.

6. The physical simulation device for mechanical slag removal, extraction, drilling, grouting, and sealing process according to claim 1, characterized in that, Each permeation slit on the wall of the support pipe is elongated and extends along the axial direction of the support pipe.

7. The physical simulation device for mechanical slag removal, extraction, drilling, grouting, and sealing process according to claim 1, characterized in that, Each set of simulated cracks includes multiple simulated cracks, which are arranged to extend radially along the support tube.

8. The physical simulation device for mechanical slag removal, extraction, drilling, grouting, and sealing process according to claim 1, characterized in that, The slurry output pipeline is connected to the first grouting pipe via a quick connector.

9. The physical simulation device for mechanical slag removal, extraction, drilling, grouting, and sealing process according to claim 1, characterized in that, A pressure gauge is installed on the slurry output pipeline.

10. The physical simulation device for mechanical slag removal, extraction, drilling, grouting, and sealing process according to claim 1, characterized in that, It also includes a second grouting pipe; One end of the second grouting pipe is located between the first bag sealer and the second bag sealer, and a one-way valve is provided at one end of the second grouting pipe. The other end of the second grouting pipe leads to the outside of the box body, and the grout output pipeline can be connected to the other end of the second grouting pipe.

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