Three-dimensional plasma pulse all-around solid cutting coal seam method

Abstract

The application discloses a three-dimensional plasma pulse all-around stereoscopic cutting coal seam method, which comprises the following steps: drilling a bottom lane full section, putting a gas, cooperating with a plasma jet device, exciting a plasma guide electrode, accelerating CO2 gas jetting, until multi-stage pulse cooperates with gas impact to realize coal seam fracturing cutting, and meanwhile, drilling positions are arranged in cross arrangement on the same dimensional surface, so that multi-section cluster fracturing coal seams are realized in different drilling, all-around stereoscopic cutting coal seam is realized, and stereoscopic cracks are penetrated, the application has the characteristics of environmental protection, high efficiency, high energy and multifunction, can fully utilize CO2 waste gas, does not cause environmental pollution, is more environmentally friendly, and can generate high-speed and high-energy-density gas flow by utilizing CO2 waste gas and cooperating with a plasma jet device to realize all-around cutting of the coal seam.

Description

Technical Field

[0001] This invention relates to a three-dimensional coal seam development method, specifically a three-dimensional plasma pulse omnidirectional three-dimensional cutting method for coal seams, belonging to the field of coal seam development technology. Background Technology

[0002] Coal mine gas refers to the large amount of gas generated during coal formation and stored in the pores and fractures of the coal seam. For coal seams with high gas content and low permeability, gas dynamics are severe during coal seam fracturing, geological conditions are complex, and the coal seam permeability is poor.

[0003] Existing technologies, particularly conventional fracturing techniques, suffer from drawbacks such as high water consumption, significant fracturing fluid pollution, and limited fracturing network morphology. Furthermore, during coal mining, the underground ore seams contain high concentrations of CO2, which is released when the ore is extracted and comes into contact with air. Additionally, coal mines contain large amounts of methane gas, which reacts during blasting and other mining methods, generating substantial amounts of CO2 waste gas. Therefore, efficiently utilizing the CO2 waste gas emitted during coal seam mining is a crucial issue in current coal seam development. Summary of the Invention

[0004] The purpose of this invention is to provide a three-dimensional plasma pulse all-round three-dimensional cutting method for coal seams, which can make full use of CO2 waste gas and will not cause environmental pollution. At the same time, it utilizes CO2 gas in conjunction with plasma jet cutting technology to perform multi-stage cluster fracturing of coal seams in different wells, which has a strong impact fracturing force on the target coal seam, and achieves all-round three-dimensional cutting of coal seams with three-dimensional fracture penetration.

[0005] To achieve the above objectives, the present invention provides a method for three-dimensional plasma pulse omnidirectional stereoscopic cutting of coal seams, comprising the following steps: Step 1: Drill a hole from the bottom roadway into the coal seam, place the gas-coordinated plasma jet into the hole, and use a crane to move the gas-coordinated plasma jet upward into the coal seam to the deepest position of the coal seam borehole. Step 2: Stop the moving gas-coordinated plasma jet generator, and then use the exhaust gas treatment system to treat the CO2 exhaust gas to remove impurities and dust. At the same time, adjust the gas composition to provide suitable gas conditions for plasma jet generation. Then, start the release of the CO2 exhaust gas collected in the compression tank, and supply the CO2 exhaust gas to the gas-coordinated plasma jet generator through the gas pipeline. Step 3: Turn on the energy storage power device to discharge the energy storage power device, and at the same time turn on the electric field control system on the gas-coordinated plasma jet handle to transfer energy along the cable through the jet focusing and accelerator to multiple electric terminals in the gas-coordinated plasma jet. Step 4: The discharge effect is generated in the jet focusing and accelerator in Step 3. The plasma impacts the coal body on one hand and interacts with the CO2 gas flow output from the high-speed gas pipeline on the other. The CO2 gas is accelerated and ejected towards the jet nozzle to form a high-speed gas flow. The two-way cooperation repeatedly fracturing the coal seam at the current position and towards the surrounding coal seam to form multiple clusters of fracture channels. Each fracture channel gradually extends into the interior of the coal reservoir, making the coal reservoir fracture network between the boreholes connected. This process is repeated to complete the one-dimensional three-dimensional cutting of the coal seam. Step 5: Extract the gas-coordinated plasma jet and then perform gas extraction on the one-dimensional coal seam. After extraction, place the gas-coordinated plasma jet into the current extraction stage, turn on multiple plasma guiding electrodes, and make the gas-coordinated plasma jet repeatedly fracture the coal seam between the top and bottom roadways at the current position, so that multiple fractures in each full-hole section can further develop and expand, realizing the two-dimensional cutting and fracturing process. Step Six: After completing the two-dimensional cutting and fracturing, the gas in the coal reservoir will enter the top roadway horizontal well in large quantities through the fractures formed by fracturing and permeability enhancement. At this time, the gas-coordinated plasma jet generator is removed to extract the gas, thus completing the three-dimensional horizontal fracturing.

[0006] Furthermore, the present invention installs a positioning sensor at the front end of the gas-coordinated plasma jet injector. This positioning sensor can determine the position of the gas-coordinated plasma jet injector in the borehole in real time, thereby enabling the gas-coordinated plasma jet injector to reach the deepest position of the well within the coal reservoir.

[0007] The present invention provides an electric field control system and a gas pipeline controller on the handle of a gas-coordinated plasma jet generator. The electric field control system is connected to an energy storage power device via a cable. The high-voltage wire and the ground wire of the cable are respectively connected to the plasma electrode and the ground electrode. The gas pipeline controller is connected to the jet focusing and accelerator and is surrounded by an insulating dielectric sleeve.

[0008] The gas-coordinated plasma jet generator of this invention has a generation frequency of 10-80Hz and a voltage range of 20-500Kv.

[0009] In this invention, each row of drill holes consists of 5-8 holes with a horizontal spacing of 30-50m and a vertical spacing of 15-35m.

[0010] The number of plasma impact clusters in this invention is 8.

[0011] The distance between wells in this invention is 150-500m.

[0012] Compared with existing technologies, this invention utilizes CO2 gas-coordinated plasma jet cutting technology for coal seams. CO2 waste gas is stored in a compression tank through compression or liquefaction and supplied to a gas-coordinated plasma jet injector via a gas pipeline. Simultaneously, the plasma in the injector utilizes high-frequency discharge, interacting synergistically with the CO2 gas flow. This generates dual high-pressure shock waves, high-speed airflow, and thermal expansion force through the jet nozzle to impact and fracture the coal reservoir, creating a three-dimensional fracture network and providing an efficient migration channel for gas. Based on this concept, the invention proposes a multi-stage pulsed gas impact method for coal seam fracturing and cutting. This involves drilling the entire bottom roadway, deploying the gas-coordinated plasma jet injector, activating the plasma guiding electrode, and accelerating the injection of CO2 gas until multi-stage pulsed gas impact is achieved. Simultaneously, the drilling positions are arranged crosswise on the same dimension, allowing for multi-stage cluster fracturing of the coal seam in different boreholes, achieving all-round three-dimensional cutting of the coal seam and penetrating three-dimensional fractures. This invention is environmentally friendly, highly efficient, high-energy, and multifunctional. It fully utilizes CO2 waste gas without causing environmental pollution, making it more environmentally friendly. By using CO2 waste gas and other gas-coordinated plasma jet generators, high-speed and high-energy-density airflow can be generated to achieve all-round cutting of coal seams. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 A schematic diagram of a gas-coordinated plasma jet generator; Figure 3 This is a schematic diagram of the structure of a gas-coordinated plasma electrode jet nozzle.

[0014] In the diagram: 1. Coal seam, 2. Waste gas treatment system, 3. Bottom roadway, 4. Energy storage power supply device, 5. Cable, 6. Gas-coordinated plasma jet injector, 7. Gas pipeline, 8. Compression tank, 9. Handle, 10. Electric field control system, 11. Gas pipeline controller, 12. Cable, 13. Jet focusing and accelerator, 14. Insulating medium sleeve, 15. High-speed gas pipeline, 16. Fixing device, 17. Compressible slide, 18. Electrode, 19. Gas-coordinated plasma electrode jet nozzle, 20. Drilling well. Detailed Implementation

[0015] The invention will now be further described with reference to the accompanying drawings.

[0016] like Figures 1-3 As shown, a three-dimensional plasma pulse omnidirectional stereoscopic cutting method for coal seams includes the following steps: Step 1: Drill a hole from bottom roadway 3 to coal seam 1, place the gas-coordinated plasma jet 6 into the hole, and use a crane to move the gas-coordinated plasma jet 6 to the deepest position of the coal seam hole. Step 2: Stop the moving gas-coordinated plasma jet generator 6, and then use the exhaust gas treatment system 2 to treat the CO2 exhaust gas to remove impurities and dust, while adjusting the gas composition to provide suitable gas conditions for plasma jet generation. Then, open the release compression tank 8 to release the CO2 exhaust gas collected in the release tank 8, so that the CO2 exhaust gas is supplied to the gas-coordinated plasma jet generator 6 through the gas pipeline 7. Step 3: Turn on the energy storage power device 4 to discharge the energy storage power device 4, and at the same time turn on the electric field control system 10 on the handle 9 of the gas-coordinated plasma jet 6 to transfer energy along the cable 12 through the jet focusing and accelerator 13 to the multiple electrodes 18 in the gas-coordinated plasma jet 6. Step 4: In Step 3, a discharge effect is generated in the jet focusing and accelerator. The plasma impacts the coal body on one hand and interacts with the CO2 gas flow output from the high-speed gas pipeline 15 on the other. The CO2 gas is accelerated and ejected towards the jet nozzle to form a high-speed gas flow. The two-way synergy repeatedly fracturing the coal seam at the current position and towards the surrounding coal seam to form multiple clusters of fracture channels. Each fracture channel gradually extends into the interior of the coal reservoir, making the coal reservoir fracture network between the boreholes connected. This process is repeated to complete the one-dimensional three-dimensional cutting of the coal seam. Step 5: Extract the gas-coordinated plasma jet 6, and then perform gas extraction on the one-dimensional coal seam. After the extraction is completed, put the gas-coordinated plasma jet into the current extraction stage, turn on multiple plasma guiding electrodes, and make the gas-coordinated plasma jet 6 repeatedly fracturing the coal seam between the top roadway at the current position, so that multiple fractures in each full-hole section can be further developed and expanded, realizing the two-dimensional cutting fracturing process. Step Six: After completing the two-dimensional cutting and fracturing, the gas in the coal reservoir will enter the top roadway horizontal well in large quantities through the fractures formed by fracturing and permeability enhancement. At this time, the gas-coordinated plasma jet 6 is removed to carry out gas extraction, thereby completing the three-dimensional horizontal fracturing.

[0017] A positioning sensor is installed at the front end of the gas-coordinated plasma jet 6. The positioning sensor can determine the position of the gas-coordinated plasma jet in the borehole in real time, so that the gas-coordinated plasma jet can reach the deepest position in the coal reservoir.

[0018] An electric field control system 10 and a gas pipeline controller 11 are provided on the handle 9 of the gas-coordinated plasma jet generator 6. The electric field control system 10 is connected to the energy storage power supply device 4 via a cable 5. The high-voltage wire and the ground wire of the cable are connected to the plasma electrode and the ground electrode respectively via a fixing device 16. The fixing device 16 is installed on a compressible slide rail 17. One end of the compressible slide rail 17 is connected to the electrode 18, thereby adjusting the electrode emission distance.

[0019] The gas pipeline controller 11 is connected to the jet focusing and accelerator 13, and the outer layer of the gas pipeline controller 11 is surrounded by an insulating dielectric sleeve 14.

[0020] The gas-coordinated plasma jet generator 6 has a generation frequency of 10-80Hz and a voltage range of 20-500Kv.

[0021] Each row of drill holes consists of 5-8 holes, with a horizontal spacing of 30-50m and a vertical spacing of 15-35m.

[0022] The number of plasma impact clusters is 8.

[0023] This invention enables efficient cutting. The plasma jet of this invention has high energy and high velocity, which can quickly cut coal seams and improve mining efficiency.

[0024] This invention requires no water resources. Compared with traditional water jet or mechanical cutting methods, this device does not require additional water resources, thus reducing water consumption and environmental pollution.

[0025] This invention has the advantages of low vibration and noise, generating less vibration and noise during plasma jet cutting, thus reducing interference and impact on the surrounding environment and workers.

[0026] This invention can reduce dust generation. The plasma jet cutting process of this invention produces less coal dust, which helps to reduce dust pollution and protect the health of workers.

[0027] After being converted by plasma jet, a portion of the CO2 waste gas of this invention can be transformed into useful chemicals or fuels, thus realizing resource utilization. Example

[0028] A specific embodiment of the present invention is provided. The gas-coordinated plasma jet generator 6 used in the present invention has a generation frequency of 50Hz and a voltage of 300KV; the distance between the boreholes 20 in the present invention is 350m, with 6 boreholes in each row, a horizontal spacing of 40m, and a vertical spacing of 25m; the number of plasma impact clusters in the present invention is 8. Step 1: Drill a borehole from bottom roadway 3 into coal seam 1, and place the gas-coordinated plasma jet 6 into the borehole. Use a crane to transport the gas-coordinated plasma jet 6 to the deepest position of the coal seam borehole. This invention installs a positioning sensor at the front end of the gas-coordinated plasma jet 6. The positioning sensor can determine the position of the gas-coordinated plasma jet in the borehole in real time, so that the gas-coordinated plasma jet reaches the deepest position in the coal reservoir.

[0029] Step 2: Stop the moving gas-coordinated plasma jet generator 6, and then use the exhaust gas treatment system 2 to treat the CO2 exhaust gas to remove impurities and dust. At the same time, adjust the gas composition to provide suitable gas conditions for plasma jet generation. This invention can use a single gas, which is also the simplest way. For example, when using the purest CO2 gas, it is only necessary to filter out other impurity gases in the CO2 exhaust gas. Different gases produce plasmas with different properties and jet characteristics. Therefore, the appropriate gas should be selected according to the specific needs. Gas ionization: Exposing CO2 waste gas to an electric field causes it to ionize. The ionization process will cause some molecules in the CO2 waste gas to dissociate into positive ions and free electrons, forming plasma. Plasma formation: Ionized gas becomes plasma, which contains a large number of positive ions and free electrons. The high energy and high temperature characteristics of plasma make it a powerful tool. Plasma jet acceleration: By applying an external electric field or other acceleration methods, charged particles in plasma can be accelerated and formed into a high-speed jet; Then, the CO2 waste gas collected in the release compression tank 8 is turned on, so that the CO2 waste gas is supplied to the gas-coordinated plasma jet 6 through the gas pipeline 7. Step 3: Turn on the energy storage power device 4 to discharge the energy storage power device 4, and at the same time turn on the electric field control system 10 on the handle 9 of the gas-coordinated plasma jet 6 to transfer energy along the cable 12 through the jet focusing and accelerator 13 to the multiple electrodes 18 in the gas-coordinated plasma jet 6. Step 4: In Step 3, a discharge effect is generated in the jet focusing and accelerator. The plasma impacts the coal body on one hand and interacts with the CO2 gas flow output from the high-speed gas pipeline 15 on the other. The CO2 gas is accelerated and ejected towards the jet nozzle to form a high-speed gas flow. The two-way synergy repeatedly fracturing the coal seam at the current position and towards the surrounding coal seam to form multiple clusters of fracture channels. Each fracture channel gradually extends into the interior of the coal reservoir, making the coal reservoir fracture network between the boreholes connected. This process is repeated to complete the one-dimensional three-dimensional cutting of the coal seam. Step 5: Extract the gas-coordinated plasma jet 6, and then perform gas extraction on the one-dimensional coal seam. After the extraction is completed, put the gas-coordinated plasma jet into the current extraction stage, turn on multiple plasma guiding electrodes, and make the gas-coordinated plasma jet 6 repeatedly fracturing the coal seam between the top roadway at the current position, so that multiple fractures in each full-hole section can be further developed and expanded, realizing the two-dimensional cutting fracturing process. Step Six: After completing the two-dimensional cutting and fracturing, the gas in the coal reservoir will enter the top roadway horizontal well in large quantities through the fractures formed by fracturing and permeability enhancement. At this time, the gas-coordinated plasma jet 6 is removed to carry out gas extraction, thereby completing the three-dimensional horizontal fracturing.

[0030] The present invention provides an electric field control system 10 and a gas pipeline controller 11 on the handle 9 of the gas-coordinated plasma jet generator 6. The electric field control system 10 is connected to the energy storage power supply device 4 via a cable 5. The high-voltage wire and the ground wire of the cable are connected to the plasma electrode and the ground electrode respectively via a fixing device 16. The fixing device 16 is installed on a compressible slide rail 17. One end of the compressible slide rail 17 is connected to an electrode 18, thereby adjusting the electrode emission distance.

[0031] The gas pipeline controller 11 of the present invention is connected to the jet focusing and accelerator 13, and the outer layer of the gas pipeline controller 11 is surrounded by an insulating dielectric sleeve 14.

[0032] This invention enables efficient cutting. The plasma jet of this invention has high energy and high velocity, which can quickly cut coal seams and improve mining efficiency.

[0033] This invention requires no water resources. Compared with traditional water jet or mechanical cutting methods, this device does not require additional water resources, thus reducing water consumption and environmental pollution.

[0034] This invention has the advantages of low vibration and noise, generating less vibration and noise during plasma jet cutting, thus reducing interference and impact on the surrounding environment and workers.

[0035] This invention can reduce dust generation. The plasma jet cutting process of this invention produces less coal dust, which helps to reduce dust pollution and protect the health of workers.

[0036] After being converted by plasma jet, a portion of the CO2 waste gas of this invention can be transformed into useful chemicals or fuels, thus realizing resource utilization.

Claims

1. A method for three-dimensional plasma pulse omnidirectional stereoscopic cutting of coal seams, characterized in that, Includes the following steps: Step 1: Drill a hole from the bottom roadway into the coal seam, place the gas-coordinated plasma jet into the hole, and use a crane to move the gas-coordinated plasma jet upward into the coal seam to the deepest position of the coal seam borehole. Step 2: Stop the moving gas-coordinated plasma jet generator, and then use the exhaust gas treatment system to treat the CO2 exhaust gas to remove impurities and dust. At the same time, adjust the gas composition to provide suitable gas conditions for plasma jet generation. Then, start the release of the CO2 exhaust gas collected in the compression tank, and supply the CO2 exhaust gas to the gas-coordinated plasma jet generator through the gas pipeline. Step 3: Turn on the energy storage power device to discharge the energy storage power device, and at the same time turn on the electric field control system on the gas-coordinated plasma jet handle to transfer energy along the cable through the jet focusing and accelerator to multiple electric terminals in the gas-coordinated plasma jet. Step 4: The discharge effect is generated in the jet focusing and accelerator in Step 3. The plasma impacts the coal body on one hand and interacts with the CO2 gas flow output from the high-speed gas pipeline on the other. The CO2 gas is accelerated and ejected towards the jet nozzle to form a high-speed gas flow. The two-way cooperation repeatedly fracturing the coal seam at the current position and towards the surrounding coal seam to form multiple clusters of fracture channels. Each fracture channel gradually extends into the interior of the coal reservoir, making the coal reservoir fracture network between the boreholes connected. This process is repeated to complete the one-dimensional three-dimensional cutting of the coal seam. Step 5: Extract the gas-coordinated plasma jet and then perform gas extraction on the one-dimensional coal seam. After extraction, place the gas-coordinated plasma jet into the current extraction stage, turn on multiple plasma guiding electrodes, and make the gas-coordinated plasma jet repeatedly fracture the coal seam between the top and bottom roadways at the current position, so that multiple fractures in each full-hole section can further develop and expand, realizing the two-dimensional cutting and fracturing process. Step Six: After completing the two-dimensional fracturing, the gas in the coal reservoir will enter the top roadway horizontal shaft in large quantities through the fractures formed by fracturing and permeability enhancement. At this time, the gas-coordinated plasma jet generator is removed to extract the gas, thereby completing the three-dimensional horizontal fracturing. The high-voltage conductor and ground conductor of the cable are connected to the plasma electrode and ground electrode respectively through a fixing device. The fixing device is installed on a compressible slide, and one end of the compressible slide is connected to the plasma electrode, thereby adjusting the plasma electrode emission distance.

2. The method according to claim 1, wherein, By installing a positioning sensor at the front end of the gas-coordinated plasma jet, the position of the gas-coordinated plasma jet inside the borehole can be determined in real time.

3. The method of claim 1, wherein the method further comprises: An electric field control system and a gas pipeline controller are installed on the handle of the gas-coordinated plasma jet generator. The electric field control system is connected to the energy storage power device via a cable, and the gas pipeline controller is connected to the jet focusing and accelerator, and is surrounded by an insulating dielectric sleeve.

4. The method of claim 1, wherein the method further comprises: The gas-coordinated plasma jet generator has a generation frequency of 10-80Hz and a voltage range of 20-500KV.

5. The method according to claim 4, wherein, Each row of drill holes consists of 5-8 holes, with a horizontal spacing of 30-50m and a vertical spacing of 15-35m.

6. The method of claim 4, wherein the method further comprises: The number of plasma impact clusters is 8.

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