Coal rock identification system and method based on spectral detection

Abstract

This invention relates to a coal and rock identification system and method based on spectral detection, comprising a collection chamber and a detection device. The detection device includes a detection chamber, a detection tube, a spectral detection mechanism, and a first suction mechanism. One end of the detection tube is connected to or disconnected from the collection chamber, and the other end extends into the detection chamber. During detection, the collection chamber is first disconnected from the detection tube, and the first suction mechanism suctions the detection chamber to create a pressure difference, resulting in a lower air pressure in the detection chamber than in the collection chamber. After suction, the detection tube is reconnected to the collection chamber, and dust particles in the collection chamber form a particle flow within the detection tube under the pressure difference. The spectral detection mechanism detects the particle flow within the detection tube. This invention utilizes static pressure difference to achieve rapid and stable dust settling to form a particle flow, improving the stability of spectral detection and accelerating the overall detection speed, enabling real-time and accurate identification of coal and rock during coal mining.

Description

Technical Field

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

[0002] As my country's primary energy source, coal identification is crucial during its mining process. The underground working environment is extremely complex and unique.

[0003] Laser-induced breakdown spectroscopy (LIBS), Raman spectroscopy, near-infrared spectroscopy (NIRS), and X-ray fluorescence (XRF) can all be used for coal quality testing. However, single-spectral techniques are generally limited by matrix effects, particle size and morphology variations, weak signals, or strong model dependencies, making it difficult to simultaneously achieve accuracy, stability, and generalization ability under complex downhole particle flow conditions. Furthermore, the prediction accuracy of most spectroscopic detection techniques tends to decrease under unstable particle flow conditions.

[0004] Furthermore, the air in coal mines often contains flammable and explosive gases such as methane (gas). This necessitates that all underground electronic equipment and systems possess extremely high explosion-proof ratings (such as intrinsically safe or flameproof). Traditional dust sampling devices often involve complex mechanical structures or electrical controls. When operating in non-vacuum environments, if the equipment is not properly sealed or malfunctions, it can easily ignite surrounding gas through electrical sparks or mechanical friction. Simultaneously, the laser used in the spectral measurement process has a high energy density, often exhibiting a brief but significant photothermal effect when exciting substances, posing a risk of ignition to any flammable gases present. These stringent explosion-proof requirements not only increase the R&D costs and size of the equipment but also limit the underground application of high-precision detection instruments, making it difficult to meet the needs for real-time, in-situ analysis of dust composition. Summary of the Invention

[0005] In view of this, the present invention provides a coal and rock identification system based on spectral detection, 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 system.

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

[0008] A coal and rock identification system based on spectral detection, the coal and rock identification system including a collection chamber for collecting coal and rock dust particles and a detection device;

[0009] The detection device includes a detection chamber, a detection tube, a spectral detection mechanism, and a first suction mechanism. One end of the detection tube is connected to or disconnected from the collection chamber, and the other end extends into the detection chamber and is connected to the detection chamber.

[0010] During detection, the collection chamber is first disconnected from the detection tube. The first suction mechanism then suctions the detection chamber to create a pressure difference, making the air pressure in the detection chamber lower than that in the collection chamber. After suction, the detection tube is reconnected to the collection chamber. The dust particles in the collection chamber form a particle flow in the detection tube under the action of the pressure difference. The spectral detection mechanism is used to detect the particle flow in the detection tube.

[0011] According to some embodiments of the present invention, the spectral detection mechanism includes a first detection unit and a second detection unit respectively disposed outside the detection chamber; the detection chamber has a first observation window corresponding to the position of the first detection unit, and the detection tube has a first detection hole corresponding to the position of the first detection unit; the detection chamber has a second observation window corresponding to the position of the second detection unit, and the detection tube has a second detection hole corresponding to the position of the second detection unit.

[0012] The first detection aperture is located above the second detection aperture, and the first observation window is located above the second observation window.

[0013] Optionally, an isolation plate is provided in the detection chamber between the first observation window and the second observation window. The isolation plate is also sleeved on the detection tube and located between the first detection hole and the second detection hole. Multiple through holes are provided on the isolation plate around the circumference of the detection tube.

[0014] The first detection unit and the second detection unit are independently selected from the LIBS detection unit, the Raman detection unit, the NIRS detection unit, and the XRF detection unit, respectively.

[0015] Further optionally, the first detection unit is a Raman detection unit or an NIRS detection unit, and the second detection unit is a LIBS detection unit or an XRF detection unit; or,

[0016] The first detection unit is a LIBS detection unit or an XRF detection unit, and the second detection unit is a Raman detection unit or an NIRS detection unit.

[0017] According to some embodiments of the present invention, a discharge pipe is connected to the bottom of the detection chamber, and a solenoid valve is provided on the discharge pipe;

[0018] The first suction mechanism is connected to the detection chamber via a first connecting pipe. A first filter screen is provided between the first suction mechanism and the detection chamber. A solenoid valve is provided on the first connecting pipe.

[0019] Optionally, the detection device further includes a detection cleaning mechanism and a temperature control plate. The detection cleaning mechanism includes a detection water inlet pipe connected to the detection chamber, and a solenoid valve is installed on the detection water inlet pipe.

[0020] The temperature control plate is located outside the detection chamber and is used to heat the inside of the detection chamber.

[0021] According to some embodiments of the present invention, the coal and rock identification system further includes a sampling device for collecting dust generated during the cutting process of a coal mining machine and pre-treating the dust to obtain coal and rock dust particles. The pre-treatment includes gas extraction and drying of the collected dust.

[0022] Optionally, the sampling device includes a collection and drying chamber and a second suction mechanism. The collection and drying chamber is used to collect and dry the dust generated during the cutting process of the coal mining machine. The second suction mechanism is used to suction the collection and drying chamber so that the air pressure inside the collection and drying chamber is lower than the outside atmospheric pressure. The collection chamber is connected to or disconnected from the collection and drying chamber.

[0023] Optionally, a first electronic valve is provided between the collection chamber and the collection drying chamber, and a second electronic valve is provided between the collection chamber and the detection tube, wherein the first electronic valve and the second electronic valve constitute two opposite sidewalls of the collection chamber.

[0024] Optionally, the second suction mechanism is connected to the collection and drying chamber via a second connecting pipe, and a second filter screen is provided between the second suction mechanism and the collection and drying chamber, and a solenoid valve is provided on the second connecting pipe.

[0025] Optionally, the sampling device further includes a sampling cleaning mechanism, which includes a sampling inlet pipe connected to the sampling and drying chamber and a drain pipe connected to the bottom of the sampling and drying chamber. Solenoid valves are respectively installed on the sampling inlet pipe and the drain pipe.

[0026] Optionally, the collection and drying chamber is equipped with a blowing and drying mechanism.

[0027] Optionally, the sampling device further includes a sampling tube connected to the collection and drying chamber, and a solenoid valve is provided on the sampling tube.

[0028] Optionally, the coal and rock identification system further includes a temperature and humidity sensor for detecting the temperature and humidity inside the collection and drying chamber.

[0029] Optionally, the first suction mechanism and the second suction mechanism are air pumps.

[0030] Optionally, the coal and rock identification system further includes a control processor, which has a built-in coal and rock identification algorithm. The control processor is also connected to the spectral detection mechanism, the first suction mechanism, the second suction mechanism, and all solenoid valves.

[0031] The second technical solution adopted by the present invention is a coal and rock identification method. The coal and rock identification method adopts the coal and rock identification system described above. The method includes, when detecting coal and rock dust particles, firstly disconnecting the collection chamber from the detection tube, then having a first suction mechanism suction the detection chamber to create a pressure difference between the collection chamber and the detection chamber. After suction ends, the detection tube is then connected to the collection chamber, and a spectral detection mechanism is activated simultaneously. The dust particles in the collection chamber form a particle flow in the detection tube under the action of the pressure difference. The spectral detection mechanism detects the particle flow in the detection tube to obtain characteristic spectral data.

[0032] According to some embodiments of the present invention, the coal and rock identification system further includes a sampling device, the sampling device including a collection and drying chamber and a second suction mechanism, the collection and drying chamber being used to collect and dry dust generated during the cutting process of the coal mining machine, the second suction mechanism being used to suction the collection and drying chamber to make the air pressure inside the collection and drying chamber lower than the outside atmospheric pressure, and the collection chamber being connected to or disconnected from the collection and drying chamber;

[0033] The method further includes a sampling step, which specifically includes: disconnecting the collection drying chamber from the collection chamber; the first suction mechanism suctions the collection drying chamber to draw the dust generated during the coal cutting process into the collection drying chamber; then disconnecting the dust inlet of the collection drying chamber; the first suction mechanism continues to suction the collection drying chamber to reduce the air pressure inside the collection drying chamber, and the suction ends.

[0034] The dust particles are connected to the collection and drying chamber and then fall into the collection chamber. The connection between the collection and drying chamber and the collection chamber is then disconnected.

[0035] Optionally, the coal and rock identification method further includes a step of cleaning the collection and drying chamber and the detection chamber. The cleaning includes rinsing the collection and drying chamber with water after each batch of dust particles is collected, and cleaning the detection chamber after each batch of dust particles is detected.

[0036] The coal and rock identification method also includes a step of drying the detection chamber after cleaning.

[0037] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0038] This invention utilizes static pressure difference to achieve rapid and stable dust drop to form a particle flow, thereby improving the stability of spectral detection and accelerating the overall detection speed, enabling real-time and accurate identification of coal and rock during the coal mining process.

[0039] Furthermore, the present invention pre-treats the collected dust using a sampling device, effectively reducing the concentration of combustible gas in the detection chamber, fundamentally blocking the necessary conditions for an explosion, and effectively avoiding the risk of underground gas explosion. Attached Figure Description

[0040] 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.

[0041] Figure 1 This is a schematic diagram of the structure of the coal and rock identification system based on spectral detection provided in an embodiment of the present invention;

[0042] Figure 2 for Figure 1 A schematic diagram of the collection chamber of a coal and rock identification system;

[0043] Figure 3 for Figure 1 A schematic diagram of the isolation plate of the coal and rock identification system;

[0044] In the picture:

[0045] 1. Sampling tube; 2. Collection chamber; 3. First suction mechanism; 4. Detection tube; 6. Air drying mechanism; 7. Second suction mechanism; 9. First connecting pipe; 10. Second connecting pipe; 11. First filter screen; 12. Second filter screen; 13. Collection water inlet pipe; 14. Drain pipe; 15. Detection water inlet pipe; 16. Temperature control board; 17. Temperature and humidity sensor; 18. Discharge pipe; 19. First detection unit; 20. Second detection unit; 21. Isolation plate; 22. Through hole; 23. Synchronous observation unit;

[0046] L1, First electronic gate valve; L2, Second electronic gate valve; A1, First solenoid valve; A2, Second solenoid valve; A3, Third solenoid valve; A4, Fourth solenoid valve; A5, Fifth solenoid valve; A6, Sixth solenoid valve; A7, Seventh solenoid valve; E1, Acquisition and drying chamber; E2, Detection chamber; E3, Collection chamber. Detailed Implementation

[0047] Laser-induced breakdown spectroscopy (LIBS) is an ideal method for online coal quality detection due to its advantages such as in-situ operation, speed, and no need for sample pretreatment. However, due to matrix effects and the complex interaction between the laser and the material, LIBS systems require a certain level of stability from the sample being tested. In current downhole applications, controlling the sample particle flow presents significant technical bottlenecks. The free fall of coal particles exhibits randomness and divergence, leading to large fluctuations in the spectral signal and a low signal-to-noise ratio, which restricts the accuracy and repeatability of the detection data and reduces detection precision.

[0048] Raman spectroscopy, based on the inelastic scattering effect caused by molecular vibration and rotation, can directly reflect the molecular structure and chemical bond information of substances, and has unique advantages in characterizing the organic matter structure and identifying mineral composition in coal. Its greatest advantage lies in its insensitivity to moisture and strong chemical specificity, enabling precise analysis of functional groups and carbon structures in coal, making it suitable for analyzing coal structure and metamorphic degree. However, Raman signals are relatively weak and susceptible to fluorescence background interference, requiring high sample surface homogeneity and stability under laser conditions. Its application in particle flow and complex downhole environments still faces challenges in signal stability.

[0049] Near-infrared spectroscopy (NIRS) technology enables rapid quantitative analysis of parameters such as moisture, volatile matter, and ash content in coal by detecting the overtone and combination frequency absorption characteristics of C–H, O–H, and N–H groups in molecules. Its key advantages include fast detection speed, suitability for large-scale online continuous monitoring, and strong adaptability to sample morphology, giving it a solid foundation for engineering applications in the coal industry. However, NIRS is inherently an indirect analytical method, easily affected by changes in particle size, density, and surface condition. It exhibits strong model dependence, and its prediction accuracy and model generalization ability tend to decrease under conditions of unstable particle flow or large compositional fluctuations.

[0050] X-ray fluorescence (XRF) technology, based on the physical process of elements generating characteristic X-rays upon stimulation, enables rapid and non-destructive detection of the inorganic elemental composition and content in coal. Its core advantages lie in its high elemental selectivity, good quantitative stability, and insensitivity to sample surface morphology and optical properties, making it particularly suitable for online monitoring of coal ash composition and harmful elements. However, XRF primarily reflects information at the elemental level, with limited ability to characterize light elements and organic matter. Furthermore, radiation safety and equipment protection must be carefully considered in downhole applications.

[0051] In summary, LIBS, Raman, NIRS, and XRF each possess irreplaceable advantages in coal quality detection, but their information dimensions and applicable boundaries differ significantly. LIBS and XRF offer rapid, multi-element response capabilities at the elemental level, with the former suitable for in-situ excitation and the latter exhibiting superior quantitative stability. Raman and NIRS, on the other hand, focus on molecular structure and functional group information, excelling in organic matter structure analysis and rapid prediction of macroscopic parameters, respectively. However, single-spectral techniques are generally limited by matrix effects, particle size and morphology variations, weak signals, or strong model dependencies, making it difficult to simultaneously achieve accuracy, stability, and generalization ability under complex downhole particle flow conditions. Multispectral fusion can achieve complementarity between elemental and molecular structure information at the information level, and at the methodological level, the uncertainty of single techniques can be reduced through cross-constraint of multi-source data, thereby improving the robustness and reliability of coal quality parameter prediction. However, multispectral fusion also faces challenges such as complex system integration, inconsistent spatial and temporal resolutions of different spectra, high data dimensionality and increased feature redundancy, and increased difficulty in multi-source calibration and model co-construction. Nevertheless, with the development of multi-source feature construction, data fusion and intelligent modeling methods, multispectral fusion detection still has significant technical advantages and application potential for achieving high-precision and stable online coal quality characterization under complex working conditions.

[0052] The air in coal mines often contains flammable and explosive gases such as methane (gas). This necessitates that all underground electronic equipment and systems possess extremely high explosion-proof ratings. These stringent explosion-proof requirements not only increase the development costs and size of equipment but also limit the application of high-precision detection instruments underground, making it difficult to meet the needs for real-time, in-situ analysis of dust composition.

[0053] Based on this, this application proposes an underground coal and rock identification system that can form a stable particle flow to adapt to high-precision spectral detection and effectively avoid the risk of underground gas explosion, so as to realize real-time and accurate identification of coal and rock in the coal mining process.

[0054] Furthermore, the main concept of this invention lies in the design of a collection chamber and a detection chamber, with a detection tube placed between the two chambers. During detection, the collection chamber is disconnected from the detection tube, and the air pressure in the detection chamber is lower than that in the collection chamber. Then, the detection tube is reconnected to the collection chamber. Utilizing the significant pressure difference between the collection and detection chambers as a driving force, the necessary gas driving force can be provided for the formation of a high-speed, collimated, and morphologically stable particle flow of coal and rock dust particles, overcoming the defects of particle trajectory divergence and uneven velocity in traditional free settling methods. This stable flow field ensures that particles can continuously and accurately pass through the focal position of the spectral detection mechanism, significantly improving the probability of effective excitation and the signal-to-noise ratio of the spectral signal, thereby ensuring the real-time performance and high accuracy of the detection data.

[0055] In addition, during the test, the suction mechanism evacuates the test chamber until the air pressure in the test chamber is lower than that in the collection chamber. After the suction ends, a static pressure difference is formed between the collection chamber and the test chamber. The particle flow formed by the dust particles under the static pressure difference is more stable, and the test results are more accurate.

[0056] A further aspect of this invention lies in the use of multi-source spectral detection in the spectral detection mechanism. By simultaneously observing different spectra of a stable particle stream falling within the detection tube in the same chamber, information at different levels of the substance (elements, molecules, etc.) can be acquired collaboratively. Simultaneous observation ensures a high degree of consistency between the two types of spectral data in terms of time and sample state, effectively avoiding data misalignment caused by particle stream fluctuations. This provides a unified and reliable data foundation for the fusion analysis of multi-source spectral information, significantly improving the physical interpretability and overall accuracy of the detection results.

[0057] A further aspect of this invention lies in the design of a sampling device. This device includes a collection and drying chamber and a suction mechanism. The collection and drying chamber is used to collect and dry the dust generated during the coal cutting process. The suction mechanism evacuates the collection and drying chamber, effectively reducing the oxygen and gas concentrations within the detection chamber, fundamentally preventing the necessary conditions for an explosion. Even when using high-energy lasers (such as LIBS) to excite coal powder to generate high-temperature plasma, the low-pressure, oxygen-deficient state within the chamber makes it difficult to ignite the surrounding environment. This achieves intrinsically safe detection in flammable and explosive scenarios such as high-gas underground mines, significantly reducing the difficulty and cost of explosion-proof design.

[0058] Referring to the accompanying drawings and specific embodiments, the structure, composition, features, and advantages of the coal and rock identification 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.

[0059] 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.

[0060] Furthermore, the terms "first," "second," "third," "fourth," "fifth," "sixth," and "seventh" 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. Therefore, a feature defined with "first," "second," "third," "fourth," "fifth," "sixth," or "seventh" may explicitly or implicitly include at least one of those features.

[0061] Figure 1A coal and rock identification system based on spectral detection is shown, which includes a collection chamber E3 for collecting coal and rock dust particles and a detection device.

[0062] The detection device includes a detection chamber E2, a detection tube 4, a spectral detection mechanism, and a first suction mechanism 3. One end of the detection tube 4 is connected to or disconnected from the collection chamber E3, and the other end extends into the detection chamber E2 and is connected to the detection chamber E2. The first suction mechanism 3 is used to suction the detection chamber E2 so that the air pressure in the detection chamber E2 is lower than the air pressure in the collection chamber E3 to form a pressure difference.

[0063] During the detection process, the collection chamber E3 is first disconnected from the detection tube 4. The first suction mechanism 3 then suctions the detection chamber E2 to create a pressure difference, making the air pressure in the detection chamber E2 lower than that in the collection chamber E3. After the suction is completed, the detection tube 4 is then connected to the collection chamber E3. The dust particles in the collection chamber E3 form a particle flow in the detection tube 4 under the action of the pressure difference. The spectral detection mechanism is used to detect the particle flow in the detection tube 4.

[0064] After the first suction mechanism is used to suction the detection chamber to make the air pressure in the detection chamber lower than that in the collection chamber, the suction ends and a static pressure difference is formed between the collection chamber and the detection chamber. The particle flow formed by the dust particles under the static pressure difference is more stable, and the detection results are more accurate.

[0065] As can be seen from the figure, the spectral detection mechanism includes a first detection unit 19 and a second detection unit 20 respectively disposed outside the detection chamber E2. A first observation window is opened in the detection chamber E2 corresponding to the position of the first detection unit 19, and a first detection hole is opened on the detection tube 4 corresponding to the position of the first detection unit 19. A second observation window is opened in the detection chamber corresponding to the position of the second detection unit, and a second observation window is opened on the detection tube 4 corresponding to the position of the second detection unit 20. The first detection hole is located above the second detection hole, and the first observation window is located above the second observation window.

[0066] In some optional embodiments, the first detection unit 19 and the second detection unit 20 are independently selected from the LIBS detection unit, the Raman detection unit, the NIRS detection unit, and the XRF detection unit, respectively. The first detection unit 19 and the second detection unit 20 preferentially select different detection units, such as the first detection unit 19 selecting the Raman detection unit or the NIRS detection unit, and the second detection unit 20 selecting the LIBS detection unit or the XRF detection unit.

[0067] To avoid interference between the two spectra during detection, an isolation plate 21 is installed inside the detection chamber E2 between the first and second observation windows. The isolation plate 21 is also fitted onto the detection tube 4 and located between the first and second detection holes. Figure 3As shown, multiple through holes 22 are arranged around the detection tube 4 on the isolation plate 21. The isolation plate 21 effectively isolates different optical observation conditions, reducing interference from near-infrared external light sources, plasma radiation, and stray light to other detection units. The through holes on the isolation plate 21 also allow clean water to pass through during subsequent cleaning.

[0068] The coal and rock identification system also includes a sampling device, which is used to collect dust generated during the coal mining process and pre-treat the dust to obtain coal and rock dust particles. The pre-treatment includes gas extraction and drying of the collected dust to reduce the gas content and water mist in the dust.

[0069] Then by Figure 1 As can be seen, the sampling device includes a sampling tube 1, a sampling and drying chamber E1 connected to the sampling tube 1, and a second suction mechanism 7. The sampling tube 1 is used to collect dust generated during the cutting process of the coal mining machine. For example, the sampling tube 1 can be set on the cutter head of the coal mining machine, and the opening of the sampling tube 1 faces the cutting face. The sampling and drying chamber E1 is used to collect and dry the dust generated during the cutting process of the coal mining machine. The second suction mechanism 7 is used to suction the sampling and drying chamber E1 so that the air pressure inside the sampling and drying chamber E1 is lower than the outside atmospheric pressure.

[0070] The collection chamber E3 is connected to or disconnected from the collection and drying chamber E1. For example... Figure 1 A first electronic valve L1 is installed between the collection chamber E3 and the collection and drying chamber E1, and a second electronic valve L2 is installed between the collection chamber E3 and the detection tube 4. The first electronic valve L1 and the second electronic valve L2 constitute two opposite side walls of the collection chamber E3.

[0071] In some alternative embodiments, the sampling device includes a collection chamber 2 with an inner cavity, the side of the collection chamber 2 is connected to the sampling tube 1, a first solenoid valve A1 is provided on the sampling tube 1, the top of the collection chamber 2 is connected to the second suction mechanism 7 through a second connecting tube 10, a second filter screen 12 is provided on the collection chamber 2 at the connection of the second connecting tube 10, and a second solenoid valve A2 is provided on the second connecting tube 10.

[0072] The first electronic gate valve L1 and the second electronic gate valve L2 are sequentially spaced at the bottom of the collection chamber 2, dividing the inner cavity of the collection chamber 2 into two independent collection and drying chambers E1 and E3. The collection and drying chamber E1 is located above the first electronic gate valve L1, and the first electronic gate valve L1 forms the side wall of the collection and drying chamber E1. Figure 2As shown, the collection chamber E3 is formed between the first electronic gate valve L1 and the second electronic gate valve L2; the second filter screen 12 is set between the collection and drying chamber E1 and the second suction mechanism 7. During the process of the second suction mechanism 7 suctioning the dust in the collection and drying chamber E1, the dust particles are intercepted by the second filter screen 12, and the gas and water mist in the dust are extracted from the collection and drying chamber E1 to reduce the gas content in the dust and fundamentally block the necessary conditions for the explosion.

[0073] The collection and drying chamber E1 is also equipped with a blowing drying mechanism 6. The blowing drying mechanism 6 has heating and air supply functions, and since it is located inside the collection and drying chamber E1, it does not introduce external gas into the collection and drying chamber E1, but instead utilizes the gas inside the collection and drying chamber E1 to form convection. Furthermore, the blowing drying mechanism 6 is located at the upper part of the collection and drying chamber E1.

[0074] Then by Figure 1 As can be seen, the sampling device also includes a sampling cleaning mechanism, which includes a sampling inlet pipe 13 connected to the sampling drying chamber E1 and a drain pipe 14 connected to the bottom of the sampling drying chamber E1. A third solenoid valve A3 is installed on the sampling inlet pipe 13 and a seventh solenoid valve A7 is installed on the drain pipe 14.

[0075] Optionally, the water inlet pipe 13 is connected to the sampling pipe 1.

[0076] The coal and rock identification system also includes a temperature and humidity sensor 17 for detecting and collecting temperature and humidity inside the drying chamber E1.

[0077] In some alternative embodiments, the upper end of the detection tube 4 is connected to the bottom of the collection chamber 2, the detection chamber E2 is located below the collection chamber E3, the lower end of the detection tube 4 extends into the detection chamber E2, and the first detection unit 19 and the second detection unit 20 are located outside the detection chamber E2.

[0078] During sampling, the collection drying chamber E1 is first disconnected from the collection chamber E3. The second suction mechanism 7 then suctions the collection drying chamber E1. After suction is complete, the collection drying chamber E1 is reconnected to the collection chamber E3, and dust particles fall into the collection chamber. Furthermore, after the system is running, the air pressure in the collection chamber E3 is lower than the air pressure in the collection drying chamber E1.

[0079] The bottom of the detection chamber E2 is connected to a discharge pipe 18, and a fifth solenoid valve A5 is installed on the discharge pipe 18. The first suction mechanism 3 is connected to the detection chamber E2 through a first connecting pipe 9, and a first filter screen 11 is installed between the first suction mechanism 3 and the detection chamber E2. A sixth solenoid valve A6 is installed on the first connecting pipe 9.

[0080] As can be seen from the figure, the detection device also includes a detection cleaning mechanism and a temperature control plate 16. The detection cleaning mechanism includes a detection water inlet pipe 15 connected to the detection chamber E2. A fourth solenoid valve A4 is installed on the detection water inlet pipe 15. The connection between the detection water inlet pipe 15 and the detection chamber E2 is located on opposite sides of the first observation window and the second observation window, respectively. This is so that when water enters the detection water inlet pipe 15, clean water can rinse the first and second observation windows, avoiding the influence of dust particles from the previous batch on light irradiation and spectral acquisition, thereby affecting real-time performance.

[0081] Furthermore, the connection between the detection inlet pipe 15 and the detection chamber E2 is located above the isolation plate 21.

[0082] The temperature control plate 16 is located around the detection chamber E2 and is used to heat and dry the inside of the detection chamber E2. For example, the temperature control plate 16 can be a PTC temperature control plate.

[0083] The coal and rock identification system also includes a control processor (not shown in the figure). The control processor has a built-in coal and rock identification algorithm and is also connected to the first detection unit 19, the second detection unit 20, the first suction mechanism 3, the second suction mechanism 7, all solenoid valves, and the temperature control board. The control processor may be a central control unit, and the first suction mechanism 3 and the second suction mechanism 7 may be air pumps.

[0084] Optionally, the spectral detection mechanism of the coal and rock identification system further includes a synchronous observation unit 23 that is signal-connected to the first detection unit 19 and the second detection unit 20 respectively, observing the signals of the first detection unit 19 and the second detection unit 20 simultaneously to achieve coordinated acquisition of information at different levels of matter (such as elements, molecules, etc.). This synchronous observation unit is signal-connected to the control processor. In other optional embodiments, a synchronous observation module can also be built into the control processor.

[0085] In an optional embodiment, the coal and rock identification system further includes a pressure sensor or pressure gauge for detecting the air pressure in the drying chamber E1, the collection chamber E3, and the detection chamber E2, respectively, and the pressure sensor or pressure gauge is also connected to the control processor.

[0086] Another embodiment of the present invention provides a coal and rock identification method, which is based on the above-mentioned method. Figure 1 The coal and rock identification system shown includes the following method:

[0087] S1, Sampling Phase

[0088] The dust generated during the coal mining machine's cutting process is drawn into the collecting and drying chamber by disconnecting the collecting and drying chamber from the collecting and drying chamber. Then, the dust inlet of the collecting and drying chamber is disconnected, and the second suction mechanism continues to suction the collecting and drying chamber, causing the air pressure inside the collecting and drying chamber to drop, at which point the suction ends.

[0089] Connect the collection and drying chamber to the collection chamber, allowing dust particles to fall into the collection chamber, and then disconnect the collection and drying chamber from the collection chamber.

[0090] S2, Detection Phase

[0091] First, disconnect the collection chamber from the detection tube. The first suction mechanism then suctions the detection chamber to create a pressure difference between the collection chamber and the detection chamber. Once suction is complete, connect the detection tube back to the collection chamber and simultaneously activate the spectral detection mechanism. Under the pressure difference, the dust particles in the collection chamber form a particle flow in the detection tube. The spectral detection mechanism detects the particle flow in the detection tube to obtain characteristic spectral data.

[0092] S3, Data Processing Stage

[0093] The characteristic spectral data is transmitted to the control processor for processing and discrimination to obtain the identification result of coal or rock;

[0094] The coal mining machine adjusts the cutting height based on the identification results.

[0095] Specifically, the implementation of step S1 includes the following steps:

[0096] Step S11, Dust Collection

[0097] The second suction mechanism 7 is turned on and the sampling tube 1 is turned on to draw the dust generated during the coal cutting process into the collection and drying chamber E1. Then the sampling tube 1 is turned off and the second suction mechanism 7 continues to draw the dust into the collection and drying chamber E1, causing the air pressure in the collection and drying chamber E1 to drop. Then the second suction mechanism 7 is turned off.

[0098] The specific operation in this step is as follows: The first solenoid valve A1, the second solenoid valve A2, and the second suction mechanism 7 are opened. The remaining solenoid valves in the sampling device, the first electronic gate valve L1, and the second electronic gate valve L2 are closed to extract and enrich the dust generated during the coal cutting process. After extraction continues for a certain period, the first solenoid valve A1 is closed, and the second solenoid valve A2 is opened to continue extraction, creating a semi-vacuum state in the collection and drying chamber E1 (the collection and drying chamber E1 contains a certain amount of gas in the semi-vacuum state to facilitate convection). Then, the second solenoid valve A2 and the second suction mechanism 7 are closed.

[0099] The dust collected at the coal cutting site contains water mist. When the water mist mixes with the coal dust in the collection and drying chamber E1, it may accumulate and adhere to the second filter screen 12 or the inner wall of the collection and drying chamber E1. Therefore, while suctioning, the blowing and drying mechanism 6 in the collection and drying chamber E1 is turned on to dry the dust. The dried particles fall and accumulate on the first electronic gate valve L1.

[0100] In this step, the extraction duration can optionally be from a few seconds to tens of seconds, such as 5-15 seconds, specifically 10 seconds. After closing the first solenoid valve A1, the extraction time can be a few seconds (such as about 5 seconds) to achieve a semi-vacuum state in the drying chamber E1, which is lower than the external atmospheric pressure, such as lower than 1 / 2 of the external atmospheric pressure.

[0101] Step S12, temporary dust storage

[0102] In this step, the first electronic gate valve L1 is opened to open the collection chamber E3, allowing dust particles in the collection drying chamber E1 to fall into the collection chamber E3. Then, the first electronic gate valve L1 is closed to close the collection chamber E3.

[0103] Step S13: Clean the collection and drying chamber

[0104] Keep the first solenoid valve A1 and the first electronic gate valve L1 closed, open the second suction mechanism 7, the second solenoid valve A2, the third solenoid valve A3 and the seventh solenoid valve A7, clean water enters the collection and drying chamber E1 from the collection inlet pipe 13 to rinse the inner wall of the collection and drying chamber E1, and the second suction mechanism 7 is used to draw out the water vapor, while the wastewater is discharged from the collection and drying chamber E1 from the drain pipe 14.

[0105] In this step, the collection and drying chamber E1 is rinsed to avoid residual dust particles in the collection and drying chamber E1, which would cause the test results to lag and affect the real-time performance of the spectral detection mechanism.

[0106] Specifically, step S2 includes the following steps:

[0107] S21. Open the first suction mechanism 3 and the sixth solenoid valve A6, close the other solenoid valves in the detection device, use the first suction mechanism 3 to suction the detection chamber E2, so that the air pressure in the detection chamber E2 is lower than the air pressure in the collection chamber E3, and then close the first suction mechanism 3 and the sixth solenoid valve A6.

[0108] In this step, the first suction mechanism 3 suctions the detection chamber E2 to create a certain degree of vacuum inside the detection chamber E2.

[0109] S22. Close the fourth solenoid valve A4, the fifth solenoid valve A5, and the sixth solenoid valve A6, and open the second electronic gate valve L2. At the same time, the first detection unit 19 and the second detection unit 20 are opened simultaneously. At this time, since the air pressure in the detection chamber E2 is lower than the air pressure in the collection chamber E3, the dust particles in the collection chamber E3 fall into the detection chamber E2 through the detection tube 4 under the action of the pressure difference. The dust particles form a particle flow in the detection tube 4 under the action of the pressure difference. The first detection unit 19 and the second detection unit 20 detect the particle flow in the detection tube 4 and obtain characteristic spectral data.

[0110] In this step, since a certain degree of vacuum is formed in the detection chamber E2, on the one hand, the gas content can be greatly reduced to prevent gas explosion (the explosion logic changes from traditional isolation explosion protection to environmental condition explosion protection). On the other hand, a pressure difference can be formed between the collection chamber E3 and the detection chamber E2 to assist in the formation of particle flow and improve the effect of spectral detection. Moreover, the pressure difference between the two is a static pressure difference, making the formation of particle flow more stable.

[0111] S23. Close the first detection unit 19 and the second detection unit 20, close the second electronic gate valve L2, and open the fourth solenoid valve A4, the fifth solenoid valve A5, the sixth solenoid valve A6 and the first suction mechanism 3. Clean water enters the detection chamber E2 through the detection inlet pipe 15 and rinses the detection chamber E2. The clean water also rinses the first observation window and the second observation window of the detection chamber E2 to prevent residual dust particles from affecting the light irradiation and spectral acquisition of the next batch of dust particles.

[0112] During the rinsing process, water vapor is also drawn out by the first suction mechanism 3, while wastewater is discharged from the detection chamber E2 through the discharge pipe 18. After rinsing, the temperature control plate 16 is turned on to heat and dry the detection chamber E2 to maintain a dry environment inside the detection chamber E2.

[0113] In the above method, by utilizing the collection chamber setup, sampling and testing of dust particles from the same batch are performed sequentially; for adjacent batches of dust particles, sampling and testing can be performed simultaneously, ensuring the real-time nature of coal and rock detection. That is, after the coal and rock identification system is activated, while detecting the Nth batch (current batch) of dust particles, the sampling device can collect dust particles from the N+1th batch (next batch).

[0114] In the above method, after the coal and rock identification system is activated, during the first data acquisition process, the air pressure in the collection chamber E3 will be higher than that in the collection and drying chamber E1. However, after cyclical data acquisition, due to the vacuuming of the detection chamber E2, the air pressure in the collection chamber E3 will eventually be lower than that in the collection and drying chamber E1, but higher than that in the detection chamber E2, and this pressure will remain constant throughout the subsequent data acquisition and detection processes. Therefore, from the start of the second detection process, the pressure difference always exists between the three chambers, allowing the entire device to form a "collection-detection-emission" cycle.

[0115] Compared with traditional coal and rock identification technologies, this coal and rock identification system has at least the following advantages:

[0116] (1) The vacuum environment significantly reduces the risk of explosion.

[0117] This coal and rock identification system effectively reduces the oxygen and gas concentration in the detection chamber by creating a negative pressure environment inside the system's components through vacuum suction, fundamentally preventing the necessary conditions for an explosion. Even when using high-energy lasers (such as LIBS) to excite coal powder to generate high-temperature plasma, the low-pressure, oxygen-deficient state within the chamber makes it difficult to ignite the surrounding environment. This achieves intrinsically safe detection in flammable and explosive scenarios such as high-gas underground mines, significantly reducing the difficulty and cost of explosion-proof design.

[0118] (2) Pressure difference drives stable particle flow to improve detection accuracy

[0119] This coal and rock identification system utilizes a collection chamber E3 designed for temporary storage of dust particles. The significant pressure difference between this chamber and the external chamber acts as a driving force, providing the necessary gas propulsion for a high-speed, collimated, and morphologically stable flow of coal and rock dust particles. This overcomes the shortcomings of traditional free settling methods, such as particle trajectory divergence and uneven velocity. Furthermore, this pressure difference is static, resulting in a more stable particle flow compared to dynamic pressure differences. This stable flow field ensures that particles continuously and accurately pass through the focal point of the optical detection mechanism, significantly improving the probability of effective excitation and the signal-to-noise ratio of the spectral signal, thereby guaranteeing the real-time performance and high accuracy of the detection data.

[0120] (3) The coal and rock identification system can reduce the risk of explosion of combustible gas by using the vacuum environment, and can also realize the rapid and stable falling of coal powder particles by using the pressure difference circulation flow, thereby improving the stability of spectral detection and speeding up the overall detection speed.

[0121] (4) Synchronous acquisition of multi-source spectral information and enhanced physical consistency

[0122] This device achieves the coordinated acquisition of information at different levels of matter (elements, molecules, etc.) by simultaneously detecting different spectral detection units in the upper and lower sections of a tubular, stably falling particle stream within the same chamber. Simultaneous observation ensures a high degree of consistency between the two types of spectral data in terms of time and sample state, effectively avoiding data misalignment caused by particle stream fluctuations. This provides a unified and reliable data foundation for the fusion analysis of multi-source spectral information, significantly improving the physical interpretability and overall accuracy of the detection results.

[0123] (5) Decoupling of observation conditions and improvement of system anti-interference capability

[0124] By placing a perforated isolation plate between the two spectral detection regions, effective isolation of different optical observation conditions is achieved while ensuring continuous particle passage, reducing interference from near-infrared external light sources, plasma radiation, and stray light to the other detection unit. This structural design improves the signal-to-noise ratio and repeatability of each spectral signal while also considering system integration compactness and engineering feasibility, enhancing the stability and long-term operational reliability of the multispectral detection system under complex operating conditions.

[0125] (6) Applicable to rapid detection applications in various high-risk environments

[0126] The proposed particle flow circulation sampling and detection device based on vacuum pressure difference conditions proposed in this coal and rock identification system has broad applicability, not limited to the coal mining field, but also applicable to any industrial scenario with both explosion risks and rapid component detection requirements, such as petrochemicals and powder processing. This coal and rock identification system provides a universal safety platform for various high-energy laser or precision optical detection technologies, which can both physically isolate explosive gases and stably transport samples, greatly expanding the application range of high-precision detection equipment in hazardous industrial environments.

[0127] 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 system based on spectral detection, characterized in that, The coal and rock identification system includes a collection chamber and a detection device for collecting coal and rock dust particles; The detection device includes a detection chamber, a detection tube, a spectral detection mechanism, and a first suction mechanism. One end of the detection tube is connected to or disconnected from the collection chamber, and the other end extends into the detection chamber and is connected to the detection chamber. During testing, the collection chamber is first disconnected from the detection tube. The first suction mechanism then suctions the detection chamber to create a pressure difference, making the air pressure in the detection chamber lower than that in the collection chamber. After suctioning, the detection tube is then connected to the collection chamber. The dust particles in the collection chamber form a particle flow in the detection tube under the action of the pressure difference. The spectral detection mechanism is used to detect the particle flow inside the detection tube.

2. The coal and rock identification system according to claim 1, characterized in that, The spectral detection mechanism includes a first detection unit and a second detection unit respectively disposed outside the detection chamber. The detection chamber has a first observation window corresponding to the position of the first detection unit, and the detection tube has a first detection hole corresponding to the position of the first detection unit. The detection chamber has a second observation window corresponding to the position of the second detection unit, and the detection tube has a second detection hole corresponding to the position of the second detection unit. The first detection aperture is located above the second detection aperture, and the first observation window is located above the second observation window.

3. The coal and rock identification system according to claim 2, characterized in that, An isolation plate is provided in the detection chamber between the first observation window and the second observation window. The isolation plate is also sleeved on the detection tube and located between the first detection hole and the second detection hole. Multiple through holes are provided on the isolation plate around the circumference of the detection tube. The first detection unit and the second detection unit are independently selected from the LIBS detection unit, the Raman detection unit, the NIRS detection unit, and the XRF detection unit, respectively.

4. The coal and rock identification system according to claim 3, characterized in that, The first detection unit is a Raman detection unit or an NIRS detection unit, and the second detection unit is a LIBS detection unit or an XRF detection unit; or, The first detection unit is a LIBS detection unit or an XRF detection unit, and the second detection unit is a Raman detection unit or an NIRS detection unit.

5. The coal and rock identification system according to claim 1, characterized in that, The bottom of the detection chamber is connected to a discharge pipe, and a solenoid valve is installed on the discharge pipe; The first suction mechanism is connected to the detection chamber via a first connecting pipe. A first filter screen is provided between the first suction mechanism and the detection chamber. A solenoid valve is provided on the first connecting pipe.

6. The coal and rock identification system according to claim 5, characterized in that, The detection device also includes a detection cleaning mechanism and a temperature control plate. The detection cleaning mechanism includes a detection water inlet pipe connected to the detection chamber, and a solenoid valve is installed on the detection water inlet pipe. The temperature control plate is located outside the detection chamber and is used to heat the inside of the detection chamber.

7. The coal and rock identification system according to any one of claims 1 to 6, characterized in that, The coal and rock identification system also includes a sampling device, which is used to collect dust generated during the coal mining machine cutting process and pre-treat the dust to obtain coal and rock dust particles. The pre-treatment includes gas extraction and drying of the collected dust.

8. The coal and rock identification system according to claim 7, characterized in that, The sampling device includes a collection and drying chamber and a second suction mechanism. The collection and drying chamber is used to collect and dry the dust generated during the cutting process of the coal mining machine. The second suction mechanism is used to suction the collection and drying chamber so that the air pressure inside the collection and drying chamber is lower than the outside atmospheric pressure. The collection chamber is connected to or disconnected from the collection and drying chamber.

9. The coal and rock identification system according to claim 8, characterized in that, A first electronic valve is provided between the collection chamber and the collection-drying chamber, and a second electronic valve is provided between the collection chamber and the detection tube, wherein the first and second electronic valves constitute two opposing sidewalls of the collection chamber; and / or, The second suction mechanism is connected to the collection and drying chamber via a second connecting pipe, and a second filter screen is provided between the second suction mechanism and the collection and drying chamber. A solenoid valve is provided on the second connecting pipe.

10. The coal and rock identification system according to claim 8, characterized in that, The sampling device further includes a sampling cleaning mechanism, which includes a sampling inlet pipe connected to the sampling and drying chamber and a drain pipe connected to the bottom of the sampling and drying chamber. Solenoid valves are respectively installed on the sampling inlet pipe and the drain pipe.

11. The coal and rock identification system according to claim 8, characterized in that, The collection and drying chamber is equipped with a blowing and drying mechanism; and / or, The sampling device further includes a sampling tube connected to the collection and drying chamber, and a solenoid valve is installed on the sampling tube; and / or, The coal and rock identification system also includes a temperature and humidity sensor for detecting the temperature and humidity inside the collection and drying chamber; and / or, The first suction mechanism and the second suction mechanism are air pumps.

12. The coal and rock identification system according to claim 8, characterized in that, The coal and rock identification system also includes a control processor, which has a built-in coal and rock identification algorithm. The control processor is also connected to the spectral detection mechanism, the first suction mechanism, the second suction mechanism, and all solenoid valves.

13. A method for coal and rock identification, characterized in that, The coal and rock identification method employs the coal and rock identification system according to any one of claims 1 to 12, and the method includes the following steps: When detecting coal and rock dust particles, the collection chamber is first disconnected from the detection tube. The first suction mechanism then suctions the detection chamber to create a pressure difference between the collection chamber and the detection chamber. After suction is completed, the detection tube is then connected to the collection chamber, and the spectral detection mechanism is activated. The dust particles in the collection chamber form a particle flow in the detection tube under the action of the pressure difference. The spectral detection mechanism detects the particle flow in the detection tube to obtain characteristic spectral data. The characteristic spectral data is transmitted to the control processor for processing and discrimination to obtain the identification result of coal or rock; and the coal mining machine adjusts the cutting height according to the identification result.

14. The coal and rock identification method according to claim 13, characterized in that, The coal and rock identification system also includes a sampling device, which includes a collection and drying chamber and a second suction mechanism. The collection and drying chamber is used to collect and dry the dust generated during the cutting process of the coal mining machine. The second suction mechanism is used to suction the collection and drying chamber so that the air pressure inside the collection and drying chamber is lower than the outside atmospheric pressure. The collection chamber is connected to or disconnected from the collection and drying chamber. The method further includes a sampling step, which specifically includes: disconnecting the collection and drying chamber from the collection chamber; the first suction mechanism suctions the collection and drying chamber to draw the dust generated during the coal cutting process into the collection and drying chamber; then disconnecting the dust inlet of the collection and drying chamber; the first suction mechanism continues to suction the collection and drying chamber to reduce the air pressure inside the collection and drying chamber; and the suction ends. The dust particles are connected to the collection and drying chamber and then fall into the collection chamber. The connection between the collection and drying chamber and the collection chamber is then disconnected.

15. The coal and rock identification method according to claim 14, characterized in that, The coal and rock identification method further includes a step of cleaning the collection and drying chamber and the detection chamber. The cleaning includes rinsing the collection and drying chamber with water after each batch of dust particles is collected, and cleaning the detection chamber after each batch of dust particles is detected. The coal and rock identification method also includes a step of drying the detection chamber after cleaning.

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