Rockbreaking device and method combining liquid nitrogen jet and particle impact

Abstract

A rock-breaking device and method combining a liquid nitrogen jet and particle impact. [Solution] The rock breaking device includes a liquid nitrogen jetting system and a particle impact system. The liquid nitrogen jetting system includes at least a liquid supply assembly and a hollow drill rod, the liquid supply assembly supplies pressurized liquid nitrogen to the hollow drill rod, and a plurality of liquid nitrogen nozzles are provided around the hollow drill rod, the hollow drill rod injects liquid nitrogen into the rock body through the liquid nitrogen nozzles in a drill hole in the rock wall. The particle impact system includes a particle acceleration assembly and a particle nozzle, the particle acceleration assembly accelerates particles and injects the particles through the particle nozzles into the rock wall near the drill hole.

Description

Technical Field

[0001] The present invention relates to the technical field of rock stratum excavation, and specifically, to a rock breaking device and a rock breaking method that combine liquid nitrogen jet and particle impact.

Background Art

[0002] In the process of coal seam mining and underground excavation operations, it is inevitable to face hard rock. Common rock breaking methods include the drilling method of pre-drilling blast holes, filling explosives in the holes, and detonating the explosives, and the mechanical rock breaking method. The mechanical rock breaking method refers to a method of using a mechanical rock breaking device to apply a concentrated load from the outside to the rock mass to crush the rock mass. The mechanical rock breaking method has advantages such as being safer and more efficient, and is currently the mainstream method for underground construction.

[0003] However, when crushing hard rock by the traditional mechanical rock breaking method, the wear of the cutting tool is accelerated, which not only directly affects the construction efficiency, but also easily causes construction accidents such as destabilization of the excavation surface and collapse of the coal rock layer when replacing the cutting tool. How to reduce the wear of the cutting tool and at the same time achieve a relatively good rock breaking effect is a bottleneck problem for realizing high-efficiency rock stratum excavation.

[0004] Therefore, it is necessary to provide a technical solution to improve the deficiencies of the above-mentioned prior art.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The object of the present invention is to overcome the deficiencies in the above-mentioned prior art, and the present invention provides a rock breaking device and a rock breaking method that combine liquid nitrogen jet and particle impact.

Means for Solving the Problems

[0006] To achieve the above object, the present invention provides the following technical solution.

[0007] A rock-breaking device that combines a liquid nitrogen jet and particle impact, including a liquid nitrogen jet fracturing system and a particle impact system, The liquid nitrogen injection fracturing system includes at least a liquid supply assembly and a hollow drill rod (hollow drilling rod, hollow boring rod), the liquid supply assembly supplies pressurized liquid nitrogen (pressurized liquid nitrogen) to the hollow drill rod, a plurality of liquid nitrogen nozzles are provided around the circumferential direction of the hollow drill rod, and the hollow drill rod injects liquid nitrogen into the interior of the rock body through the liquid nitrogen nozzles in a drill hole (borehole) in the rock wall. The particle impact system includes a particle acceleration assembly and a particle nozzle, the particle acceleration assembly accelerating particles and injecting them through the particle nozzle into the rock wall near the drill hole, a drill connected to the tip of the hollow drill rod, a bridge plug and a packer spaced apart on the hollow drill rod behind the drill, the liquid nitrogen nozzle located on the hollow drill rod between the bridge plug and the packer, the liquid supply assembly includes at least an autoboosting calibre liquid nitrogen container and a liquid nitrogen buffer tank, the autoboosting calibre liquid nitrogen container and the liquid nitrogen buffer tank are connected by a first pipeline, the autoboosting calibre liquid nitrogen container fills the hydraulic buffer tank with liquid nitrogen, the first pipeline is provided with a first solenoid valve, the liquid supply assembly further includes a liquid pump, the liquid pump is located downstream of the buffer tank and pressurizes the liquid nitrogen in the liquid nitrogen buffer tank into a liquid nitrogen jet, A second pipeline connects the liquid inlet (liquid inlet) of the liquid pump to the liquid nitrogen buffer tank, and a second solenoid valve is provided in the second pipeline. The particle acceleration assembly includes a particle acceleration tube, an impact rod, a pneumatic pump, and a gas cylinder, wherein the impact rod is guided and moved within the particle acceleration tube. The gas cylinder is connected to the pneumatic machine via a pipe and supplies gas to the pneumatic machine, and a gas cylinder valve is provided in the pipe between the gas cylinder and the pneumatic machine. The aforementioned pneumatic fan is connected to the particle accelerating tube via a pipe and supplies compressed gas to the particle accelerating tube. The particle acceleration assembly further includes a particle filling mechanism, the particle filling mechanism includes at least a sleeve and an inner tube, the inner tube being located inside the sleeve and communicating with one side of a particle acceleration tube, and supplying particles to the particle acceleration tube. A particle chamber is connected to one side of the inner tube via a pipe, and the particle chamber is for replenishing particles in the inner tube. A base is provided at the lower part of the sleeve, the inner tube fits into the base, a base plate is provided at the lower part of the inner tube, a gasket is guided and sealed into the inner tube, a spring is provided between the gasket and the base plate, and a plurality of particles are supported on the upper part of the gasket. The particle filling mechanism further includes a vacuum pump, a fourth conduit is provided between the vacuum pump and the particle accelerating tube, and a fourth solenoid valve for controlling the reset of the impact rod is provided in the fourth conduit. A fifth conduit is provided between the vacuum pump and the base plate, the fifth conduit penetrates the base plate and enters the inner tube, and a fifth solenoid valve for compressing the spring is provided in the fifth conduit. The particles in the particle chamber are iron or steel particles; this is a rockbreaking device that combines a liquid nitrogen jet with particle impact.

[0008] This invention further provides a rock-breaking method combining a liquid nitrogen jet and particle impact, using a rock-breaking apparatus that combines the above-mentioned liquid nitrogen jet and particle impact, and the rock-breaking method is Step 1 involves first drilling multiple holes in the rock face, and then inserting multiple hollow drill rods, each connected to a liquid supply assembly, into one of the drill holes. Step 2 involves opening the first solenoid valve to transport a quantitative amount of liquid nitrogen from the self-pressurizing liquid nitrogen storage tank to the liquid nitrogen buffer tank, and then closing the first solenoid valve. Step 3 involves opening the second and third solenoid valves and opening the liquid pump, which pressurizes the liquid nitrogen in the liquid nitrogen buffer tank into a liquid nitrogen jet and then sends it to a hollow drill rod, injecting the liquid nitrogen jet into the rock body through the liquid nitrogen nozzle on the hollow drill rod, and setting the time for which the liquid nitrogen continues to be injected into the interior of the rock body at a set pressure. Step 4 involves opening the gas cylinder valve, starting the pneumatic machine to compress the gas, sending it to the particle accelerating tube, moving the impact rod at high speed along the particle accelerating tube under the action of high-pressure air, impacting the particles, ejecting them at high speed from the particle nozzle, and forcing the particles onto the rock wall between the four drills, thus fracturing the rock. Step 4 involves opening the fourth solenoid valve and starting the vacuum pump to reset the impact rod, repeating the above process, and repeatedly impacting the rock wall with particles. Step 5 involves opening the fifth solenoid valve and particle valve, starting the vacuum pump, causing the gasket to press down on the spring, and replenishing the particles in the particle chamber into the inner tube when the particles in the inner tube are depleted. This includes repeating steps 1-5 until the set rock drilling operation is completed, and step 6. Beneficial effects

[0009] In this rockbreaking device, high-pressure liquid nitrogen is first injected into the rock face through a hollow drill rod, and the liquid nitrogen diffuses around the drill hole. Under the action of the liquid nitrogen, freeze-breaking fracture occurs in the rock body, gradually weakening it and causing internal cracks. Subsequently, particles are accelerated to high speed through a particle acceleration assembly and ejected through a particle nozzle into the rock face around the drill hole, fracturing the rock body with the impact of the particles. The weakening effect of the liquid nitrogen increases the brittleness of the rock body, causing internal cracks, and the high-speed particles have sufficient impact energy to fracture the weakened hard rock. This rockbreaking device not only overcomes the wear problem of traditional mechanical rockbreaking tools but also significantly improves drilling efficiency. Moreover, this rockbreaking device enables waterless operation throughout the entire process, and since almost no liquid nitrogen remains after vaporization, it can make the rockbreaking process safer and more environmentally friendly.

[0010] After opening the gas cylinder valve and starting the pneumatic machine to compress the gas, it is sent to the particle accelerating tube. The impact rod moves at high speed along the particle accelerating tube under the action of high-pressure air, colliding with the particles and ejecting them at high speed from the particle nozzle, causing the particles to be ejected into the rock wall between the four drills, thus fracturing the rock. The particles collide with the rock wall between the four drills, and the particle impact action is combined as much as possible with the liquid nitrogen jets released from multiple hollow drill rods to obtain a better rock fracturing effect.

[0011] A vacuum pump can be used to generate negative pressure inside the particle loading tube, facilitating the resetting of the impact rod, and also to create negative pressure inside the inner tube, which is convenient for compressing the spring with a gasket and replenishing particles in the inner tube. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic diagram of the rock-breaking device structure. [Figure 2] This is a schematic diagram of the structure of a hollow drill rod. [Figure 3] This is a schematic diagram of the particle packing apparatus. [Figure 4] This is a schematic diagram of the excavation work surface. [Modes for carrying out the invention]

[0013] According to a specific embodiment of the present invention, as shown in Figures 1-4, the present invention provides a rock-breaking device that combines a liquid nitrogen jet and a particle impact system, including a liquid nitrogen jet fracturing system and a particle impact system. The liquid nitrogen injection fracturing system includes at least a liquid supply assembly and a hollow drill rod 17, the liquid supply assembly supplying pressurized liquid nitrogen to the hollow drill rod 17, and a plurality of liquid nitrogen nozzles 20 are provided circumferentially on the hollow drill rod 17, the hollow drill rod 17 injecting liquid nitrogen into the interior of the rock body through the liquid nitrogen nozzles 20 in a drill hole in the rock wall. The particle impact system includes a particle acceleration assembly and a particle nozzle 39, the particle acceleration assembly which accelerates the particles and ejects them through the particle nozzle 39 into the rock wall near the drill hole.

[0014] In this rockbreaking device, high-pressure liquid nitrogen is first injected into the rock face through a hollow drill rod 17, and the liquid nitrogen diffuses around the drill hole. Under the action of the liquid nitrogen, freeze-breaking occurs in the rock body, gradually weakening the rock and causing internal cracks. Subsequently, particles are accelerated to high speed through a particle acceleration assembly and ejected through a particle nozzle 39 into the rock face around the drill hole, fracturing the rock body with the impact of the particles. The weakening effect of the liquid nitrogen increases the brittleness of the rock body, causing internal cracks, and the high-speed particles have sufficient impact energy to fracture the weakened hard rock. This rockbreaking device not only overcomes the wear problem of traditional mechanical rockbreaking tools but also significantly improves drilling efficiency. Moreover, this rockbreaking device enables waterless operation throughout the entire process, and since almost no liquid nitrogen remains after vaporization, it can make the rockbreaking process safer and more environmentally friendly.

[0015] A drill 18 is connected to the tip of the hollow drill rod 17. A bridge plug 21 and a packer 19 are provided at intervals on the hollow drill rod 17 behind the drill 18. The liquid nitrogen nozzle 20 is located on the hollow drill rod 17 between the bridge plug 21 and the packer 19.

[0016] In one embodiment of the present application, the hollow drill rod 17 is attached to the drilling rig 16. The drill rod and the drill 18 are rotated through the drilling rig 16 to drill a drill hole in the rock wall. After clearing the hole, the hollow drill rod 17 having the liquid nitrogen nozzle 20 is inserted into the drill hole. Then, high-pressure liquid nitrogen is input into the hollow drill rod 17 through the liquid supply assembly. The bridge plug 21 and the packer 19 can play a role in sealing the gap between the hollow drill rod 17 and the drill hole, thereby preventing the liquid nitrogen from escaping from the drill hole and avoiding the liquid nitrogen from penetrating into the rock mass around the drill hole, so as to expand the weakening range of the rock mass as much as possible.

[0017] The liquid supply assembly includes at least a self-pressurized liquid nitrogen storage tank 1 and a liquid nitrogen buffer tank 8. A first pipeline is provided for communicating between the self-pressurized liquid nitrogen storage tank 1 and the liquid nitrogen buffer tank 8. The self-pressurized liquid nitrogen storage tank 1 fills the hydraulic buffer tank with liquid nitrogen, and a first solenoid valve 7 is provided in the first pipeline. In one embodiment of the present application, the on / off of the first pipeline is controlled through the first solenoid valve 7. The self-pressurized liquid nitrogen storage tank 1 fills the liquid nitrogen buffer tank 8 with liquid nitrogen through the first pipeline, and the liquid nitrogen in the liquid nitrogen buffer tank 8 is transported to the hollow drill rod 17 after being pressurized.

[0018] In this embodiment, a liquid nitrogen buffer tank 8 is provided downstream of the self-pressurized liquid nitrogen storage tank 1. The required amount of liquid nitrogen for each use is first transferred to the liquid nitrogen buffer tank 8, and after the liquid nitrogen is released from the liquid nitrogen buffer tank 8 and pressurized, it is input into each hollow drill rod 17. By arranging like this, the safety of the use process of the rock-breaking device can be further enhanced.

[0019] In this embodiment, the self-pressurized liquid nitrogen storage tank 1 includes a liner 2 and a casing 3, and a pressure increasing valve 4, a safety valve 5, and a vent valve 6 are provided thereon.

[0020] The liquid supply assembly further includes a liquid pump 10. The liquid pump 10 is provided downstream of the buffer tank. The liquid pump 10 pressurizes the liquid nitrogen in the liquid nitrogen buffer tank 8 into a liquid nitrogen jet. A second pipeline is connected between the liquid inlet of the liquid pump 10 and the liquid nitrogen buffer tank 8, and a second solenoid valve 9 is provided on the second pipeline.

[0021] In one embodiment of the present application, the on / off of the second chain (the second pipeline) is controlled via the second solenoid valve 9. The liquid pump 10 is a reciprocating cryogenic liquid pump 10. After pressurizing the liquid nitrogen in the liquid nitrogen buffer tank 8 via the liquid pump 10 and converting the liquid nitrogen into a liquid nitrogen jet, it is input into the hollow drill rod 17 and injected into the rock mass, thereby increasing the penetration energy of the liquid nitrogen and the weakening effect on the rock mass.

[0022] The drive source of the liquid pump 10 includes a frequency conversion control box 13, a motor 12, and a transmission box 11. The output end of the motor 12 is transmission-connected to the input end of the transmission box 11, and the output end of the transmission box 11 is transmission-connected to the input shaft of the liquid pump 10. The frequency conversion control box 13 is connected to the motor 12 and controls the rotational speed of the motor 12. In one embodiment of the present application, a transmission box 11 is provided between the liquid pump 10 and the motor 12 for transmission. The transmission box 11 plays a role in reducing speed and increasing torque. By controlling the rotational speed of the motor 12 via the frequency conversion control box 13, accurate adjustment of the operating pressure and injection frequency of the reciprocating cryogenic liquid pump 10 is realized, and furthermore, liquid nitrogen can be injected into the rock mass at the required pressure and injection frequency according to different rock conditions.

[0023] A third conduit is connected to the liquid outlet of the liquid pump 10, and a third solenoid valve 15 and a pressure gauge 14 are provided in the third conduit. The third conduit is connected to each of the multiple hollow drill rods 17 via a branch pipe so that the liquid pump 10 can simultaneously transport pressurized liquid nitrogen jets to the multiple hollow drill rods 17. In one embodiment of the present invention, the third solenoid valve 15 is used to control the on / off state of the third conduit, and the pressure gauge 14 is used to measure the pressure of the liquid nitrogen in the third conduit to determine whether the liquid nitrogen being transported to the hollow drill rods 17 has reached a set pressure. Simultaneously, multiple sets of drilling rigs 16 and drill rods are provided, and each hollow drill rod 17 is connected to a third pipeline via a single branch pipe, allowing the liquid pump 10 to simultaneously transport pressurized liquid nitrogen jets to multiple hollow drill rods 17. This enables multiple hollow drill rods 17 to simultaneously inject liquid nitrogen jets into a wider area of ​​the rock mass, maximizing the area of ​​rock mass weakened by liquid nitrogen and achieving a better weakening effect on the rock mass.

[0024] The particle acceleration assembly includes a particle acceleration tube 27, an impact rod 28, a pneumatic fan 24, and a gas cylinder 22, the impact rod 28 being guided and moved within the particle acceleration tube 27. The gas cylinder 22 is connected to the pneumatic fan 24 via a pipe and supplies gas to the pneumatic fan 24, and a gas cylinder valve 23 is provided in the pipe between the gas cylinder 22 and the pneumatic fan 24. The pneumatic fan 24 is connected to the particle acceleration tube 27 via a pipe and supplies compressed gas to the particle acceleration tube 27.

[0025] In one embodiment of the present invention, a gas cylinder valve 23 is used to control the supply of gas from a gas cylinder 22 to an air pump, wherein there may be multiple gas cylinders 22, and the multiple gas cylinders 22 are connected in parallel to a pipe connected to the air pump, and one gas cylinder valve 23 is provided at the gas outlet position of each gas cylinder 22.

[0026] A ball valve 25 for controlling the on / off state of the pipe between the pneumatic fan 24 and the particle accelerating tube 27 is provided, along with a pressure gauge 26 for monitoring whether the gas pressure after pressurization by the pneumatic fan has reached a standard. The gas in the gas cylinder 22 is compressed via the pneumatic fan 24 and then input into the particle accelerating tube 27, where the high-pressure gas presses against the impact rod 28, causing it to move at high speed within the particle accelerating tube 27. The impact rod 28 collides with particles at high speed, giving the particles large kinetic energy, which is then ejected from the particle nozzle 39 and impacts the weakened rock mass with liquid nitrogen, causing the rock mass to break.

[0027] The particle acceleration assembly further includes a particle filling mechanism, which includes at least a sleeve 33 and an inner tube 36, the inner tube 36 being located inside the sleeve 33 and communicating with one end of the particle acceleration tube 27, supplying particles to the particle acceleration tube 27. A particle storage chamber 31 is connected to one end of the inner tube 36 via a pipe, and the particle storage chamber 31 replenishes the inner tube 36 with particles.

[0028] In one embodiment of the present invention, the particles contained in the particle storage 31 may be particles of a hard material such as iron particles or steel particles, and a particle valve 32 is provided in the pipe between the particle storage 31 and the inner pipe 36, and the particle valve 32 is used to control the on / off state of the pipe so that the particle storage 31 controls the replenishment transport of particles to the inner pipe 36.

[0029] A base 37 is provided at the bottom of the sleeve 33, the inner tube 36 fits into the base 37, a base plate is provided at the bottom of the inner tube 36, a gasket 34 is guided and sealed into the inner tube 36, a spring 35 is provided between the gasket 34 and the base plate, and multiple particles are supported on the top of the gasket 34. The particle filling mechanism further includes a vacuum pump 30, a fourth conduit is provided between the vacuum pump 30 and the particle accelerating tube 27, and a fourth solenoid valve 29 for controlling the reset of the impact rod 28 is provided in the fourth conduit. A fifth conduit is provided between the vacuum pump 30 and the base plate. This fifth conduit penetrates the base plate and enters the inner tube 36. A fifth solenoid valve 38 for compressing the spring 35 is provided in the fifth conduit.

[0030] In one embodiment of the present invention, the gasket 34 is pressed by the spring 35, which presses the particles inside the inner tube 36 so that the impact rod 28 impacts and accelerates the particles, pushing the particles into the particle accelerating tube 27.

[0031] The fourth solenoid valve 29 is used to control the on / off state of the fourth pipeline. After the fourth solenoid valve 29 opens, the particle accelerating tube 27 is evacuated via the vacuum pump 30, generating negative pressure inside the particle accelerating tube 27, which resets the impact rod 28 to its original position and facilitates the subsequent impact process.

[0032] The fifth solenoid valve 38 is used to control the on / off state of the fifth pipeline. After the fifth solenoid valve 38 opens, a vacuum is created in the inner pipe 36 between the gasket 34 and the base plate via the vacuum pump 30 to generate negative pressure, which compresses the spring 35 in the gasket 34. At this time, the particle valve 32 opens, and particles from the particle storage 31 are replenished into the inner pipe 36.

[0033] This invention further provides a rock-breaking method combining a liquid nitrogen jet and particle impact, using a rock-breaking apparatus that combines a liquid nitrogen jet and particle impact as described above, and the rock-breaking method is Step 1 involves first drilling multiple holes in the rock face, and then inserting multiple hollow drill rods 17, to which liquid supply assemblies are connected, into each of the drill holes. Step 2 involves opening the first solenoid valve 7 to transport a quantitative amount of liquid nitrogen from the self-pressurizing liquid nitrogen storage tank 1 to the liquid nitrogen buffer tank 8, and then closing the first solenoid valve 7. Step 3 involves opening the second solenoid valve 9 and the third solenoid valve 15, and opening the liquid pump 10, which pressurizes the liquid nitrogen in the liquid nitrogen buffer tank 8 into a liquid nitrogen jet, then sends it to the hollow drill rod 17, injects the liquid nitrogen jet into the rock body through the liquid nitrogen nozzle 20 on the hollow drill rod 17, and setting the time for which the liquid nitrogen continues to be injected into the interior of the rock body at a set pressure. Step 4 involves opening the gas cylinder valve 23, starting the pneumatic pump 24 to compress the gas and then sending it to the particle accelerating tube 27, where the impact rod 28 moves at high speed along the particle accelerating tube 27 under the action of high-pressure air, impacting the particles and ejecting them at high speed from the particle nozzle 39, causing the particles to be ejected into the rock wall between the four drills, thus fracturing the rock. Step 4 involves opening the fourth solenoid valve 29 and starting the vacuum pump 30 to reset the impact rod 28, and repeating the above process to repeatedly impact the rock wall with particles, thereby fracturing the rock. In this embodiment, the particles impact the rock wall between the four drills, and step 4 aims to combine the particle impact action with the liquid nitrogen jets released from the multiple hollow drill rods 17 as much as possible to obtain a better rock fracturing effect. Step 5, when the particles in the inner tube 36 are depleted, opens the fifth solenoid valve 38 and particle valve 32, and activates the vacuum pump 30, causing the gasket 34 to compress the spring 35, thereby replenishing the particles in the particle storage 31 into the inner tube 36. In this embodiment, the vacuum pump 30 can be used to generate negative pressure inside the particle mounting tube, facilitating the reset of the impact rod 28, and also to generate negative pressure inside the inner tube 36, which is convenient for replenishing the particles in the inner tube 36 by compressing the spring 35 with the gasket 34. Step 6 includes repeating steps 1 through 5 until the set rock drilling operation is completed. [Explanation of Symbols]

[0034] 1. Self-pressurizing liquid nitrogen storage tank 2 Rainer 3. Casing 4. Pressure boosting valve 5. Safety valve 6. Ventilation valve 7. First solenoid valve 8. Liquid nitrogen buffer tank 9. Second solenoid valve 10 liquid pumps 11 Transmission box 12 motors 13 Frequency conversion control box 14. Pressure Gauge 15. Third solenoid valve 16 Drilling rig 17 Hollow Drill Rod 18 Drills 19 Packers 20 Liquid nitrogen nozzles 21 Bridge Plug 22 gas cylinders 23 Gas cylinder valve 24 Pneumatic machines 25 Ball valve 26 Pressure gauge 27 Particle Accelerator Tube 28 Collision rod 29. Fourth solenoid valve 30 Vacuum pumps 31 Particle Warehouse 32 Particle valve 33 sleeves 34 Gasket 35 Spring 36 Inner tube 37 Pedestal 38. Fifth Solenoid Valve 39 Particle Nozzle

Claims

1. A rock-breaking device that combines a liquid nitrogen jet and particle impact, including a liquid nitrogen jet fracturing system and a particle impact system, The liquid nitrogen injection fracturing system includes at least a liquid supply assembly and a hollow drill rod, the liquid supply assembly supplies pressurized liquid nitrogen to the hollow drill rod, a plurality of liquid nitrogen nozzles are provided circumferentially on the hollow drill rod, and the hollow drill rod injects liquid nitrogen into the interior of the rock body through the liquid nitrogen nozzles in a drill hole in the rock wall. The particle impact system includes a particle acceleration assembly and a particle nozzle, the particle acceleration assembly accelerating particles and injecting them through the particle nozzle into the rock wall near the drill hole, a drill connected to the tip of the hollow drill rod, a bridge plug and a packer spaced apart on the hollow drill rod behind the drill, the liquid nitrogen nozzle located on the hollow drill rod between the bridge plug and the packer, the liquid supply assembly includes at least a self-pressurizing liquid nitrogen storage tank and a liquid nitrogen buffer tank, the self-pressurizing liquid nitrogen storage tank and the liquid nitrogen buffer tank are connected by a first pipeline, the self-pressurizing liquid nitrogen storage tank fills the hydraulic buffer tank with liquid nitrogen, the first pipeline is provided with a first solenoid valve, the liquid supply assembly further includes a liquid pump, the liquid pump is located downstream of the buffer tank, and the liquid pump pressurizes the liquid nitrogen in the liquid nitrogen buffer tank into the liquid nitrogen jet. A second pipeline connects the liquid inlet of the liquid pump to the liquid nitrogen buffer tank, and a second solenoid valve is provided in the second pipeline. The particle acceleration assembly includes a particle acceleration tube, an impact rod, a pneumatic fan, and a gas cylinder, wherein the impact rod is guided and moved within the particle acceleration tube. The gas cylinder is connected to the pneumatic machine via a pipe and supplies gas to the pneumatic machine, and a gas cylinder valve is provided in the pipe between the gas cylinder and the pneumatic machine. The aforementioned pneumatic fan is connected to the particle accelerating tube via a pipe and supplies compressed gas to the particle accelerating tube. The particle acceleration assembly further includes a particle filling mechanism, the particle filling mechanism includes at least a sleeve and an inner tube, the inner tube being located inside the sleeve and communicating with one side of a particle acceleration tube, and supplying particles to the particle acceleration tube. A particle chamber is connected to one side of the inner tube via a pipe, and the particle chamber is for replenishing particles in the inner tube. A base is provided at the lower part of the sleeve, the inner tube fits into the base, a base plate is provided at the lower part of the inner tube, a gasket is guided and sealed into the inner tube, a spring is provided between the gasket and the base plate, and a plurality of particles are supported on the upper part of the gasket. The particle filling mechanism further includes a vacuum pump, a fourth conduit is provided between the vacuum pump and the particle accelerating tube, and a fourth solenoid valve for controlling the reset of the impact rod is provided in the fourth conduit. A fifth conduit is provided between the vacuum pump and the base plate, the fifth conduit penetrates the base plate and enters the inner tube, and a fifth solenoid valve for compressing the spring is provided in the fifth conduit. A rock-breaking device that combines a liquid nitrogen jet with particle impact, characterized in that the particles in the particle chamber are iron particles or steel particles.

2. The rock-breaking device combining a liquid nitrogen jet and particle impact according to claim 1, characterized in that the drive source of the liquid pump includes a frequency conversion control box, a motor, and a transmission box, the output terminal of the motor is transmitted to the input terminal of the transmission box, the output terminal of the transmission box is transmitted to the input shaft of the liquid pump, and the frequency conversion control box is connected to the motor and controls the rotational speed of the motor.

3. A rock-breaking device combining a liquid nitrogen jet and particle impact, as described in claim 1, wherein a third pipeline is connected to the liquid outlet of the liquid pump, a third solenoid valve and a pressure gauge are provided in the third pipeline, and the third pipeline is connected to each of the multiple hollow drill rods via a single branch pipe so that the liquid pump transports a pressurized liquid nitrogen jet to each of the multiple hollow drill rods simultaneously.

4. A rock-breaking method combining a liquid nitrogen jet and particle impact, using a rock-breaking apparatus that combines a liquid nitrogen jet and particle impact as described in claim 3, Step 1 involves first drilling multiple holes in the rock face, and then inserting multiple hollow drill rods, each connected to a liquid supply assembly, into one of the drill holes. Step 2 involves opening the first solenoid valve, transporting a quantitative amount of liquid nitrogen from a self-pressurizing liquid nitrogen storage tank to a liquid nitrogen buffer tank, and then closing the first solenoid valve. Step 3 involves opening the second and third solenoid valves, and opening the liquid pump, which pressurizes the liquid nitrogen in the liquid nitrogen buffer tank into a liquid nitrogen jet, then sends it to a hollow drill rod, injects the liquid nitrogen jet into the rock body through the liquid nitrogen nozzle on the hollow drill rod, and setting the time for which the liquid nitrogen continues to be injected into the interior of the rock body at a set pressure. Step 4 involves opening the gas cylinder valve, starting the pneumatic machine to compress the gas, sending it to the particle accelerating tube, moving the impact rod at high speed along the particle accelerating tube under the action of high-pressure air, impacting the particles, ejecting them at high speed from the particle nozzle, and forcing the particles onto the rock wall between the four drills, thereby fracturing the rock. Step 4 involves opening the fourth solenoid valve and starting the vacuum pump to reset the impact rod, repeating the above process, and repeatedly impacting the rock wall with particles to fracture it. Step 5 involves opening the fifth solenoid valve and particle valve, starting the vacuum pump, causing the gasket to press down on the spring, and replenishing the particles in the particle chamber into the inner tube when the particles in the inner tube are depleted. A rock-breaking method combining liquid nitrogen jetting and particle impact, including step 6, which involves repeating steps 1 to 5 until the set rock drilling operation is completed.

Images