Coal rock identification experiment system and method

Abstract

The invention relates to a coal rock identification experiment system and method.The coal rock identification experiment system comprises a working condition simulation box, a draught fan, a separating and drying module and a material bin, and the draught fan is used for supplying air into the working condition simulation box; the working condition simulation box is used for feeding pulverized coal, rock powder and water mist to form a mixed sample of dust and water mist so as to simulate the real working condition of the working face of the coal mining machine; the separating and drying module is used for carrying out gas-solid separation on the mixed sample in the working condition simulation box and carrying out drying treatment on separated dust particles; the system further comprises a detection pipe connected with the material bin, a pump unit and an LIBS detection device, the pump unit is used for mixing the dust particles in the material bin with the airflow to form gas-solid two-phase flow, and the LIBS detection device is used for detecting the dust particles in the gas-solid two-phase flow. The system not only can simulate a complex coal face environment, but also can provide stable dynamic dust flow for LIBS online detection, and provides a reliable experimental verification platform for practical application of an LIBS technology in the field of coal rock recognition and development of a field system.

Description

Technical Field

[0001] This invention relates to the field of coal and rock identification technology, and specifically to a coal and rock identification experimental system and method. Background Technology

[0002] Coal and rock identification is the process of distinguishing coal from rock through various technical means. Currently, the main technical means of coal and rock identification in coal mining include vibration method, infrared spectroscopy method, gamma-ray method and visual recognition method. However, these methods still have relatively low identification accuracy and are easily affected by harsh environments such as high dust, high humidity and light changes underground, resulting in a high misjudgment rate.

[0003] LIBS (Laser-Induced Breakdown Spectroscopy) technology has been introduced into coal and rock identification due to its high precision and rapid analysis characteristics. However, before applying LIBS technology to actual coal mining, it is necessary to conduct coal mining simulation experiments in the laboratory and verify the feasibility of LIBS detection or obtain standard spectra for LIBS detection.

[0004] However, most existing experimental systems are designed for dry, clean samples and cannot systematically simulate the mine environment or provide a stable dynamic dust flow for online LIBS detection, which limits the application potential of LIBS technology in underground coal and rock identification. Summary of the Invention

[0005] In view of this, the present invention provides a coal and rock identification experimental system, thereby solving or at least alleviating one or more of the above-mentioned problems and other problems existing in the prior art.

[0006] The second objective of this invention is to provide a coal and rock identification method using a coal and rock identification experimental system.

[0007] To achieve the aforementioned objectives, the technical solution adopted by the present invention is as follows:

[0008] A coal and rock identification experimental system includes a working condition simulation chamber, a fan, a separation and drying module, and a material silo.

[0009] The fan is used to supply air into the working condition simulation box;

[0010] The working condition simulation box is used to feed coal powder, rock powder and water mist to form a mixed sample of dust and water mist to simulate the real working conditions of the coal mining machine face;

[0011] The separation and drying module is used to perform gas-solid separation on the mixed sample in the working condition simulation chamber and to dry the separated dust particles.

[0012] The material silo is used to receive dried dust particles;

[0013] The coal and rock identification experimental system also includes a detection tube, a pump unit, and a LIBS detection device connected to the material silo. The detection tube has a transparent glass tube section.

[0014] The pump unit is used to deliver gas into the detection tube and mix the dust particles in the material bin with the airflow to form a gas-solid two-phase flow.

[0015] The LIBS detection device is used to detect dust particles in the gas-solid two-phase flow within the glass tube section.

[0016] In the aforementioned coal and rock identification experimental system, optionally, the light transmittance of the glass tube segment is greater than 90%.

[0017] In the aforementioned coal and rock identification experimental system, optionally, the detection tube includes a first tube segment with one end connected to the material bin, a glass tube segment with one end connected to the other end of the first tube segment, and a second tube segment with one end connected to the other end of the glass tube segment.

[0018] The pump unit includes a first jet pump installed in the first pipe section, a second jet pump installed in the second pipe section, and an air pump connected to the first jet pump and the second jet pump respectively. The air pump is used to provide airflow to the first jet pump and the second jet pump.

[0019] Optionally, the LIBS detection device includes a laser generator and a spectrometer. The laser emitted by the laser generator is focused onto dust particles in the gas-solid two-phase flow within the glass tube section. The spectrometer has a spectral signal receiving probe that receives spectral signals through the glass tube section.

[0020] Optionally, the first pipe segment and the second pipe segment are metal pipes;

[0021] The coal and rock identification experimental system also includes an air blowing pipe connected at one end to the air pump. The air blowing pipe extends into the first pipe section and the glass pipe section, and the other end of the air blowing pipe serves as an air outlet. The air outlet is located near the position where the laser passes through the glass pipe section, so as to blow air onto the inner wall of the glass pipe section at the laser incident point.

[0022] Optionally, the other end of the second pipe section is connected to the material silo.

[0023] In the aforementioned coal and rock identification experimental system, optionally, the separation and drying module adopts a cyclone separator with drying function.

[0024] In the aforementioned coal and rock identification experimental system, optionally, the separation and drying module includes a cyclone separator and a drying collection box located at the bottom of the cyclone separator. The inlet of the cyclone separator is connected to the working condition simulation box. The cyclone separator is used to draw in the mixed sample in the working condition simulation box for gas-solid separation. The separated dust particles are sent to the drying collection box for drying treatment, and the separated gas is discharged from the gas outlet of the cyclone separator. The drying collection box is connected to both the cyclone separator and the material silo.

[0025] Optionally, the gas outlet of the cyclone separator is connected to an exhaust pipe, and a filter is installed on the exhaust pipe.

[0026] Optionally, the drying collection box includes a box body, a heating plate rotatably disposed in the box body, and a drive unit for driving the heating plate to move. The dust particles in the cyclone separator fall onto the heating plate for heating and drying, and the dried dust particles are poured into the material hopper under the rotation of the heating plate.

[0027] The coal and rock identification experimental system also includes a weighing sensor for monitoring the weight of dust particles on the heating plate.

[0028] Optionally, in the aforementioned coal and rock identification experimental system, the coal and rock identification experimental system further includes a control processor, which has a built-in coal and rock identification algorithm, and the control processor is also connected to the LIBS detection device, the separation and drying module, the pump unit, and the fan signal.

[0029] In the aforementioned coal and rock identification experimental system, optionally, an exhaust vent is provided on the material silo, and a filter screen is installed at the exhaust vent.

[0030] In the aforementioned coal and rock identification experimental system, optionally, the fan and the working condition simulation box are connected by a connecting pipe, and a filter is installed on the connecting pipe.

[0031] The second technical solution adopted by this invention is: a coal and rock identification method, wherein the method employs the aforementioned coal and rock identification experimental system, and the method includes the following steps:

[0032] Coal powder, rock powder and water mist are introduced into the working condition simulation box, and the fan is started to blow air into the working condition simulation box so that the coal powder, rock powder and water mist form a mixed sample to simulate the real working conditions of the coal mining machine face.

[0033] The separation and drying module is activated to perform gas-solid separation on the mixed sample in the working condition simulation chamber and to dry the separated dust particles. The dried dust particles are then transported to the material silo, and the separated gas is discharged from the separation and drying module.

[0034] The pump unit is started to deliver gas into the detection tube and draw dust particles from the material bin into the detection tube, so that the gas and dust particles are mixed to form a gas-solid two-phase flow;

[0035] When the gas-solid two-phase flow passes the detection position of the LIBS detection device, the LIBS detection device is triggered to detect dust particles in the gas-solid two-phase flow, thereby achieving online dynamic identification.

[0036] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0037] The coal and rock identification experimental system of this invention can not only simulate the coal mine working face, but also separate mixed samples to obtain a stable gas-solid two-phase flow of dust particles and gas, provide a stable dynamic dust flow for LIBS online detection, realize online dynamic detection and analysis of coal and rock, provide a reliable experimental verification platform for the practical application of LIBS technology in the field of coal and rock identification and the development of field systems, and provide a solid experimental and data foundation for intelligent cutting of coal mining machines.

[0038] The detection tube in the coal and rock identification experimental system of this invention uses a glass tube segment. The laser of the LIBS detection device can directly penetrate the glass tube wall and focus on the dust particles flowing inside the tube, achieving laser-induced breakdown. The spectral signal generated by the breakdown can also penetrate the glass tube wall and be accurately captured by the LIBS detection device. By using a glass tube segment, there is no need to open the detection tube, and the glass tube segment acts as an optical window. The system is completely isolated from the external environment, completely eliminating dust leakage and avoiding the problem of the laser window being contaminated by the internal dust flow. Attached Figure Description

[0039] The disclosure of this invention will become more apparent from the accompanying drawings. It should be understood that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention.

[0040] Figure 1 This is a schematic diagram of the structure of the coal and rock identification experimental system provided in an embodiment of the present invention;

[0041] Figure 2 for Figure 1 A schematic diagram of the material silo, detection pipe, pump unit, and LIBS detection device of the coal and rock identification experimental system;

[0042] In the picture:

[0043] 1. Working condition simulation chamber; 2. Fan; 3. Cyclone separator; 4. Material silo; 5. Drying and collection box; 51. Box body; 52. Heating plate; 6. LIBS detection device; 7. First pipe section; 8. Glass pipe section; 9. Second pipe section; 10. Connecting pipe; 11. Filter; 12. First jet pump; 13. Second jet pump; 14. Air pump; 15. Exhaust pipe; 16. Air blowing pipe. Detailed Implementation

[0044] The actual working environment of a coal mine is extremely complex. The dust sampling material is a multiphase aerosol composed of dust, water mist, gas, etc. Moist dust is prone to agglomeration, and gas and water mist will seriously interfere with the laser breakdown and spectral acquisition process of LIBS, making it impossible to guarantee that the LIBS detection position receives a dry, stable, and representative dust stream.

[0045] Based on this, this application proposes an integrated and controllable coal and rock identification experimental system, which can systematically simulate the working environment of a coal mine face and verify the key technical parameters and reliability of the entire chain from collection → gas-solid separation → dust drying → dynamic conveying → LIBS detection. This solves the problems of existing technologies that lack simulation of complex working conditions and cannot provide a stable dynamic dust flow for online LIBS detection.

[0046] Referring to the accompanying drawings and specific embodiments, the structure, composition, features, and advantages of the coal and rock identification experimental system of the present invention will be described below by way of example; however, all descriptions should not be construed as limiting the present invention in any way.

[0047] For any single technical feature described or implied in the embodiments submitted herein, or any single technical feature shown or implied in the various drawings, the present invention still operates in any combination or deletion among these technical features or their equivalents without any technical obstacle, and thus these further embodiments according to the present invention should also be considered within the scope of the description herein.

[0048] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature.

[0049] Reference Figure 1 and Figure 2 The coal and rock identification experimental system based on dust sampling shown includes a working condition simulation box 1, a fan 2, a separation and drying module, a material silo 4, a detection tube, a pump unit, and a LIBS detection device 6.

[0050] Depend on Figure 1As can be seen, the blower 2 is connected to the working condition simulation box 1 through the connecting pipe 10, and the connecting pipe 10 is equipped with a filter 11. The blower 2 is used to supply air into the working condition simulation box 1 to provide a stable airflow. After being purified by the filter 11, the air enters the working condition simulation box 1. The working condition simulation box 1 is used to put coal powder, rock powder and water mist into it to form a mixed sample of dust and water mist to simulate the real working conditions of the coal mining machine face.

[0051] The separation and drying module is used to perform gas-solid separation on the mixed sample in the working condition simulation chamber 1 and to dry the separated dust particles.

[0052] Material bin 4 is used to receive dried dust particles.

[0053] In some optional embodiments, the separation and drying module includes a cyclone separator 3 and a drying collection box 5 disposed at the bottom of the cyclone separator 3. The inlet of the cyclone separator 3 is connected to the working condition simulation box 1. The cyclone separator 3 is used to draw in the mixed sample in the working condition simulation box 1 and perform gas-solid separation. The separated dust particles are sent to the drying collection box 5 for drying treatment. The separated gas is discharged from the gas outlet of the cyclone separator 3, and an exhaust pipe 15 is connected to the gas outlet. A filter 11 is disposed on the exhaust pipe 15, and the fine dust contained in the gas discharged from the cyclone separator 3 is intercepted by the filter 11.

[0054] The drying collection box 5 includes a box body 51, a heating plate 52 rotatably disposed inside the box body 51, and a drive unit for driving the movement of the heating plate 52. The drive unit can be driven by a motor. When receiving wet dust particles, the heating plate 52 is placed horizontally. The wet dust particles in the cyclone separator 3 fall onto the heating plate 52 for heating and drying. After the dust particles are heated and dried, the motor drives the heating plate to flip. The dried dust particles fall into the material bin 4 after the heating plate flips.

[0055] Optionally, the heating plate is rotatably mounted at the bottom of the drying collection box via a horizontally extending shaft, which is driven by a motor.

[0056] The coal and rock identification experimental system also includes a weighing sensor for monitoring the weight of dust particles on the heating plate 52. During the experiment, the weighing sensor can also be used to monitor the dryness of the dust particles.

[0057] Optionally, to facilitate the falling of dust, a vibrator can be installed on the heating plate 52. When the heating plate is flipped, the vibrator is turned on at the same time to shake the dust into the material hopper.

[0058] In some alternative embodiments, the separation and drying module can also use a cyclone separator with drying function to separate and dry dust particles. Drying is achieved simultaneously when dust particles are separated from gas. In this way, the dried dust particles separated by the cyclone separator can be directly transported to the material silo for temporary storage.

[0059] The detection tube is connected to the material silo and has a transparent glass tube section. The pump unit is used to deliver gas into the detection tube and mix the dust particles in the material silo with the gas to form a gas-solid two-phase flow. The LIBS detection device is used to detect the dust particles in the gas-solid two-phase flow in the glass tube section.

[0060] A complete, non-perforated transparent glass tube is used as the transport channel for the gas-solid two-phase flow of dust. The laser generator and the spectral signal receiving probe of the spectrometer in the LIBS detection device are both located on the outer sides of the glass tube. The laser from the LIBS detection device directly penetrates the glass tube wall and is focused onto the dust particles flowing inside, achieving laser-induced breakdown. The spectral signal generated by the breakdown also penetrates the glass tube wall and is accurately captured by the external spectral signal receiving probe. The focal point of the laser is typically set on the central axis of the glass tube.

[0061] If holes are drilled in the metal tube and a window is installed, or if holes are drilled directly for testing, dust may leak into the environment due to poor sealing or design flaws, increasing safety and pollution risks. Furthermore, with window plates, dust particles may impact at high speed or adhere to the plate, causing it to quickly become contaminated and dirty, affecting the quality of laser projection and spectral reception. Frequent cleaning is required, making long-term stable online monitoring difficult.

[0062] Since the glass tube has no openings and serves as the optical window, the system is completely isolated from the external environment, completely eliminating dust leakage and avoiding the problem of the laser window being contaminated by internal dust flow. It also achieves complete airtightness of the dust conveying system, completely eliminating the risk of dust leakage, improving the system's safety and environmental protection, and realizing stable, maintenance-free gas-solid two-phase flow LIBS identification.

[0063] Optionally, the glass tube segment 8 has a light transmittance of more than 90% for light with a wavelength of 1064nm. The glass tube segment 8 is made of glass products without internal stress, bubbles or inclusions to prevent wavefront distortion of the beam and affect the final focusing quality, and the wall thickness is uniform.

[0064] like Figure 2 As shown, the detection tube includes a first tube section 7 with one end connected to the material bin 4, a glass tube section 8 with one end connected to the first tube section 7, and a second tube section 9 with one end connected to the other end of the glass tube section 8.

[0065] The pump unit includes a first jet pump 12 installed in the first pipe section 7, a second jet pump 13 installed in the second pipe section 9, and an air pump 14 connected to the first jet pump 12 and the second jet pump 13 respectively. The air pump 14 is used to provide airflow to the first jet pump 12 and the second jet pump 13. Dust particles in the material bin 4 are drawn into the first pipe section 7 by the airflow under the action of the first jet pump 12, flow through the glass pipe section 8, and then enter the second pipe section 9 under the action of the second jet pump 13. The dust particles form a stable gas-solid two-phase flow with the airflow in the detection tube, and the LIBS detection device is used to detect the dust particles in the gas-solid two-phase flow flowing through the glass pipe section 8.

[0066] In some alternative embodiments, the first pipe section 7 and the second pipe section 9 may be made of metal pipes, such as stainless steel pipes.

[0067] When the gas-solid two-phase flow passes through glass tube section 8, the LIBS detection device performs laser breakdown spectroscopy detection on the dust particles in the flow, realizing online dynamic identification.

[0068] Optionally, the other end of the second pipe section 9 is connected to the material bin 4, allowing the gas-solid two-phase flow to return to the material bin 4 and circulate between the detection pipe and the material bin. The high-speed flow field ensures the continuous renewal of the detection particles. During the experiment, it ensures that dry, uniform, and rapidly renewed dust particles always flow through the glass pipe section, realizing online, dynamic, and stable coal and rock composition identification. This provides a solid experimental and data foundation for online detection of dynamic dust flow in coal and rock identification under actual working conditions. Furthermore, the dust particles can be reused for experiments, while also preventing dust leakage.

[0069] Optionally, an exhaust vent is provided on the material silo 4, and a filter screen is installed at the exhaust vent to prevent dust particles from leaking out.

[0070] The LIBS detection device includes a laser generator and a spectrometer. The laser emitted by the laser generator is focused onto the flowing dust particles inside the glass tube section 8 through the glass tube section. The spectrometer has a spectral signal receiving probe, which receives spectral signals through the glass tube section.

[0071] Optionally, see also Figure 2 The coal and rock identification experimental system also includes an air blowing pipe 16 connected at one end to an air pump 14. The air blowing pipe 16 extends into the first tube section 7 and the glass tube section 8, and the other end of the air blowing pipe 16 serves as an air outlet. The air outlet is close to the position where the laser passes through the glass tube section 8, so as to blow air onto the inner wall of the glass tube section at the laser incident point to avoid dust accumulation at the laser incident point (inner wall of the glass tube section) and affect the focusing efficiency of the light at the center of the glass tube.

[0072] During the testing process, the gas in the blowing tube 16 only blows air onto the inner wall of the laser incident point of the glass tube segment, which avoids the accumulation of dust at the laser incident point and does not affect the movement of particles in the center of the glass tube segment.

[0073] The coal and rock identification experimental system also includes a control processor, which has a built-in coal and rock identification algorithm. The control processor is also connected to the LIBS detection device, the separation and drying module, the fan, and the pump unit to control the start and stop of these devices.

[0074] The control processor can be an industrial computer, a PC, or similar device.

[0075] The coal and rock identification experimental system provided in this invention can not only simulate the real coal mining face environment, but also efficiently obtain dry, non-caking representative dust samples under complex working conditions, and stably transport the dust samples to the LIBS detection device to realize online dynamic detection and analysis of LIBS. It can be used to verify the accuracy, stability and real-time performance of LIBS technology in coal dust and rock dust identification, and provide a solid experimental and data foundation for intelligent dust removal, safety monitoring and intelligent cutting of coal mining machines.

[0076] The coal and rock identification experimental system provided in this embodiment of the invention also has the following advantages:

[0077] High airtightness testing: Using a glass tube section without openings as the LIBS testing channel, the complete airtightness of the dust conveying system is achieved, completely eliminating the risk of dust leakage and improving the safety and environmental protection of the system;

[0078] Avoid window contamination: The laser directly penetrates the glass tube wall to focus, avoiding the use or exposure of LIBS laser optical windows, thus solving the problems of dust contamination, reduced detection accuracy, and frequent cleaning required when using windows.

[0079] The coal and rock identification experimental system set up above can be divided into four closely connected functional stages:

[0080] Phase 1: Working Condition Simulation Phase

[0081] The stable airflow provided by the blower enters the working condition simulation chamber after passing through the filter. Inside the working condition simulation chamber, coal powder, rock powder and water mist are manually added in a quantitative amount to form a representative dust and water mist mixture sample to simulate the real working conditions of the coal mining machine face.

[0082] This stage achieved high-fidelity working condition simulation, successfully constructing a controllable mixed simulation environment of dust, water mist, and gas (airflow from the fan simulates gas), providing an experimental basis close to actual working conditions for the development of the coal and rock identification system.

[0083] Second stage: Gas-solid separation stage

[0084] The mixed sample in the working condition simulation chamber is drawn into the cyclone separator. In the cyclone separator, the centrifugal force generated by the high-speed rotating airflow throws the denser coal dust and rock dust particles out of the airflow and they fall along the wall into the drying collection box below, thus achieving effective separation of large dust particles and gas. The separated gas (containing fine dust) is discharged from the gas outlet of the cyclone separator.

[0085] Phase 3: Dust Collection and Drying Stage

[0086] The dust is heated by a heating plate in the drying and collection box, which evaporates the moisture in the damp dust and prevents the dust from clumping. After the dust is dried, the motor is started to drive the heating plate to flip, and the dried dust is poured into the material silo in a metered manner, realizing the drying and temporary storage of the dust, and providing clump-free dry powder for subsequent cyclic testing.

[0087] The second and third stages achieve efficient gas-solid separation and dehumidification. The innovative combination of a cyclone separator for initial separation and a drying collection box effectively separates and collects dust, water mist (dehumidification), and gas (safety), ensuring the sample quality of LIBS testing.

[0088] Phase 4: Delivery and LIBS Inspection Phase

[0089] An air pump drives a first jet pump and a second jet pump to form a stable airflow. The first jet pump uses the ejection effect of the high-speed airflow to uniformly and stably entrain dry powder particles in the material bin into the flow channel, forming a stable gas-solid two-phase flow. When the gas-solid two-phase flow passes through the glass tube section, the LIBS detection device performs laser breakdown spectroscopy detection on the dust flowing in the glass tube section, realizing online dynamic identification.

[0090] This stage achieves stable dynamic LIBS detection. By using an air pump, a first jet pump, and a second jet pump, dust particles and airflow are formed into a stable gas-solid two-phase flow within the detection tube. This ensures that the glass tube section always has a dry, uniform, and rapidly replenished flow of dust particles, enabling online, dynamic, stable, and maintenance-free identification of coal and rock composition.

[0091] Another embodiment of the present invention provides a coal and rock identification method, which employs, as follows: Figures 1 to 2 The coal and rock identification experimental system shown includes the following steps:

[0092] A certain amount of coal powder, rock powder and water mist are put into the working condition simulation box, and the fan is started to blow air into the working condition simulation box so that the coal powder, rock powder and water mist form a mixed sample to simulate the real working conditions of the coal mining machine face. The air blown by the fan is equivalent to simulating the gas in the coal mining machine face.

[0093] The cyclone separator is started to draw in the mixed sample in the working condition simulation chamber and perform gas-solid separation. The separated dust particles are dried and then transported to the material silo. The separated gas is discharged from the gas outlet of the cyclone separator.

[0094] Start the pump unit to deliver gas into the detection tube and draw dust particles from the material bin into the detection tube, so that the gas and dust particles are mixed to form a gas-solid two-phase flow;

[0095] When the gas-solid two-phase flow passes the detection position of the LIBS detection device on the side of the glass tube section, the LIBS detection device is triggered to detect dust particles in the gas-solid two-phase flow, realizing online dynamic identification.

[0096] This stage enables online dynamic identification of dust particles and obtains the standard spectrum for online dynamic identification of dust particles, providing a solid experimental and data foundation for downhole online dynamic identification.

[0097] This coal and rock identification experimental system can be used to verify the accuracy, stability, and real-time performance of LIBS technology in coal dust and rock dust identification, providing a solid experimental and data foundation for intelligent dust removal, safety monitoring, and intelligent cutting of coal mining machines underground.

[0098] The above embodiments are only used to illustrate the embodiments of the present invention, and are not intended to limit the embodiments of the present invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the embodiments of the present invention. Therefore, all equivalent technical solutions also fall within the scope of the embodiments of the present invention, and the patent protection scope of the embodiments of the present invention should be defined by the claims.

Claims

1. A coal and rock identification experimental system, characterized in that, The coal and rock identification experimental system includes a working condition simulation chamber, a fan, a separation and drying module, and a material silo. The fan is used to supply air into the working condition simulation box; The working condition simulation box is used to feed coal powder, rock powder and water mist to form a mixed sample of dust and water mist to simulate the real working conditions of the coal mining machine face; The separation and drying module is used to perform gas-solid separation on the mixed sample in the working condition simulation chamber and to dry the separated dust particles. The material silo is used to receive dried dust particles; The coal and rock identification experimental system also includes a detection tube, a pump unit, and a LIBS detection device connected to the material silo. The detection tube has a transparent glass tube section. The pump unit is used to deliver gas into the detection tube and mix the dust particles in the material bin with the airflow to form a gas-solid two-phase flow. The LIBS detection device is used to detect dust particles in the gas-solid two-phase flow within the glass tube section.

2. The coal and rock identification experimental system according to claim 1, characterized in that, The light transmittance of the glass tube section is greater than 90%.

3. The coal and rock identification experimental system according to claim 1, characterized in that, The detection tube includes a first tube segment with one end connected to the material bin, a glass tube segment with one end connected to the other end of the first tube segment, and a second tube segment with one end connected to the other end of the glass tube segment. The pump unit includes a first jet pump installed in the first pipe section, a second jet pump installed in the second pipe section, and an air pump connected to the first jet pump and the second jet pump respectively. The air pump is used to provide airflow to the first jet pump and the second jet pump.

4. The coal and rock identification experimental system according to claim 3, characterized in that, The LIBS detection device includes a laser generator and a spectrometer. The laser emitted by the laser generator is focused onto dust particles in the gas-solid two-phase flow inside the glass tube section. The spectrometer has a spectral signal receiving probe, which receives spectral signals through the glass tube section.

5. The coal and rock identification experimental system according to claim 4, characterized in that, The first and second pipe sections are metal pipes; The coal and rock identification experimental system also includes an air blowing pipe connected at one end to the air pump. The air blowing pipe extends into the first pipe section and the glass pipe section, and the other end of the air blowing pipe serves as an air outlet. The air outlet is located near the position where the laser passes through the glass pipe section, so as to blow air onto the inner wall of the glass pipe section at the laser incident point.

6. The coal and rock identification experimental system according to any one of claims 3 to 5, characterized in that, The other end of the second pipe section is connected to the material silo.

7. The coal and rock identification experimental system according to claim 1, characterized in that, The separation and drying module adopts a cyclone separator with drying function, or; The separation and drying module includes a cyclone separator and a drying collection box located at the bottom of the cyclone separator. The inlet of the cyclone separator is connected to the working condition simulation box. The cyclone separator is used to draw in the mixed sample in the working condition simulation box for gas-solid separation. The separated dust particles are sent to the drying collection box for drying treatment, and the separated gas is discharged from the gas outlet of the cyclone separator. The drying collection box is connected to both the cyclone separator and the material silo.

8. The coal and rock identification experimental system according to claim 7, characterized in that, The drying and collecting box includes a box body, a heating plate rotatably disposed in the box body, and a drive unit for driving the heating plate to move. Dust particles in the cyclone separator fall onto the heating plate for heating and drying. The dried dust particles are poured into the material hopper under the rotation of the heating plate. The coal and rock identification experimental system also includes a weighing sensor for monitoring the weight of dust particles on the heating plate.

9. The coal and rock identification experimental system according to claim 1, characterized in that, The coal and rock identification experimental system also includes a control processor, which has a built-in coal and rock identification algorithm. The control processor is also connected to the LIBS detection device, the separation and drying module, the pump unit, and the fan signal connection; and / or, The material silo has an exhaust vent, and a filter screen is installed at the exhaust vent; and / or, The fan and the operating condition simulation box are connected by a connecting pipe, and a filter is installed on the connecting pipe.

10. A method for coal and rock identification, characterized in that, The method employs the coal and rock identification experimental system as described in any one of claims 1 to 9, and the method includes the following steps: Coal powder, rock powder and water mist are introduced into the working condition simulation box, and the fan is started to blow air into the working condition simulation box so that the coal powder, rock powder and water mist form a mixed sample to simulate the real working conditions of the coal mining machine face. The separation and drying module is activated to perform gas-solid separation on the mixed sample in the working condition simulation chamber and to dry the separated dust particles. The dried dust particles are then transported to the material silo, and the separated gas is discharged from the separation and drying module. The pump unit is started to deliver gas into the detection tube and draw dust particles from the material bin into the detection tube, so that the gas and dust particles are mixed to form a gas-solid two-phase flow; When the gas-solid two-phase flow passes the detection position of the LIBS detection device, the LIBS detection device is triggered to detect dust particles in the gas-solid two-phase flow, thereby achieving online dynamic identification.

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