Coal oxidation dynamic evolution multi-parameter real-time monitoring device under ultraviolet radiation

Abstract

The invention discloses a coal oxidation dynamic evolution multi-parameter real-time monitoring device under ultraviolet radiation, the device comprises a monitoring unit and a reaction unit, the monitoring unit comprises an ultraviolet radiation module, a gas monitoring module, a heat monitoring module, an active group monitoring module, a free radical monitoring module and a control unit, the reaction unit comprises a multi-channel in-situ reaction module and a coal sample reaction cavity, and a monitored coal sample is arranged in the coal sample reaction cavity; the ultraviolet radiation module is used for generating a controllable ultraviolet radiation field on the surface of the coal sample; the gas monitoring module is used for monitoring gas components released in the coal oxidation process in real time; the heat monitoring module is used for monitoring temperature distribution inside and on the surface of the coal sample; the active group monitoring module is used for tracking dynamic evolution of functional groups on the surface of the coal sample. Accurate and high-timeliness coal sample dynamic evolution monitoring is realized, and key data support is provided for revealing a coal oxidation chain reaction mechanism and a spontaneous combustion process.

Description

Technical Field

[0001] The invention relates to the technical field of coal mine safety monitoring, and in particular to a multi-parameter real-time monitoring device for the dynamic evolution of coal oxidation under ultraviolet radiation. Background Art

[0002] Spontaneous combustion of coal is a major hidden danger to coal mine safety production. Its essence is that coal undergoes oxidation reaction with oxygen under low temperature conditions, releasing heat and gradually heating up, eventually causing spontaneous combustion. At present, the monitoring technologies for the coal oxidation process mainly include: gas analysis method: evaluating the degree of oxidation by detecting changes in the concentration of characteristic gases such as CO, CO2, and CH4. However, this method has hysteresis and cannot reflect changes in the microstructure of coal; temperature monitoring method: using thermocouples or fiber optic sensors to measure the internal temperature of the coal pile, but traditional methods are difficult to achieve real-time monitoring of the three-dimensional temperature field; spectral analysis method: using infrared spectroscopy (FTIR) or electron paramagnetic resonance (EPR) technology to analyze changes in active groups and free radicals in coal, but existing equipment usually operates independently and cannot be synchronously associated with gas and temperature data.

[0003] At present, during the spontaneous combustion and low-temperature oxidation of coal, the macroscopic characteristics (gas products, heat) and microstructural characteristics (such as active groups and free radicals) of coal samples change dynamically. These changes are closely related to the spontaneous combustion mechanism of coal and the safety evaluation of coal quality. However, most of the existing detection methods use offline sampling or intermittent detection, which makes it difficult to achieve real-time monitoring of multi-dimensional signals of coal samples in a continuous time, especially under long-term ultraviolet radiation, the continuous evolution process of various parameters in coal is still difficult to fully capture.

[0004] Therefore, there is an urgent need for a comprehensive monitoring instrument that can simultaneously and continuously collect and analyze signals such as gas composition, temperature, infrared spectrum and free radicals of coal samples under ultraviolet radiation in real time, so as to reveal the inherent evolution laws of coal spontaneous combustion and low-temperature oxidation processes. Summary of the invention

[0005] The purpose of the present invention is to provide a multi-parameter real-time monitoring device for the dynamic evolution of coal oxidation under ultraviolet radiation, which realizes accurate and timely monitoring of the dynamic evolution of coal samples and provides key data support for revealing the chain reaction mechanism of coal oxidation and the spontaneous combustion process.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] A multi-parameter real-time monitoring device for the dynamic evolution of coal oxidation under ultraviolet radiation comprises a monitoring unit and a reaction unit. The monitoring unit comprises an ultraviolet radiation module, a gas monitoring module, a heat monitoring module, an active group monitoring module, a free radical monitoring module and a control unit. The reaction unit comprises a multi-channel in-situ reaction module and a coal sample reaction chamber arranged inside the multi-channel in-situ reaction module. The coal sample to be monitored is arranged in the coal sample reaction chamber.

[0008] An ultraviolet radiation module, used to generate a controllable ultraviolet radiation field on the surface of the coal sample;

[0009] Gas monitoring module, used to monitor the gas composition released during coal oxidation in real time;

[0010] Thermal monitoring module, used to monitor the temperature distribution inside and on the surface of the coal sample;

[0011] Active group monitoring module, used to track the dynamic evolution of functional groups on the surface of coal samples;

[0012] Free radical monitoring module, used to quantitatively analyze the concentration changes of free radicals during coal oxidation;

[0013] The control unit is used to synchronously regulate the operation of each module and integrate multimodal monitoring data and upload it to the cloud for fusion analysis.

[0014] Preferably, the ultraviolet radiation module is arranged directly above the coal sample reaction chamber, and includes an adjustable wavelength LED light source array, a collimating lens group, a light homogenizer, a filter switching mechanism, a cooling fan, a light intensity feedback sensor and a power controller;

[0015] The adjustable wavelength LED light source array is composed of deep ultraviolet LED, mid-ultraviolet LED and near-ultraviolet LED. The divergence angle is compressed by the collimating lens group, and the light intensity unevenness is reduced by the uniform light sheet. The wavelength is switched by the filter switching mechanism. The filter switching mechanism has multiple sets of narrow-band filters built in, and the wavelength switching is driven by a stepper motor. The light intensity feedback sensor monitors the radiation intensity in real time, and the power controller is closed-loop adjusted through the PID algorithm. The cooling fan is used to maintain stable operation of the light source.

[0016] Preferably, the gas monitoring module includes a gas sampling probe, an air pump, a gas analysis unit, a mass flow controller and an exhaust gas purification unit; wherein the gas outlet on the left side wall of the coal sample reaction chamber is connected in series with the gas sampling probe, the air pump, the mass flow controller, the gas analysis unit and the exhaust gas purification unit through a pipeline, forming a closed-loop gas circuit system protected by an inert gas; the gas analysis unit includes an NDIR sensor, an electrochemical sensor and a micro gas chromatograph arranged in parallel, and the pipeline between the air pump and the mass flow controller is a drying tube;

[0017] The air pump extracts the gas in the coal sample reaction chamber. After dehydration by the drying tube, it is distributed to the NDIR sensor, electrochemical sensor, and micro gas chromatograph by the mass flow controller; the NDIR sensor detects CO2 and CH4, the electrochemical sensor detects CO, and the micro gas chromatograph analyzes C2H4; the waste gas purification unit treats the waste gas through activated carbon adsorption and catalytic oxidation.

[0018] Preferably, the heat monitoring module includes a distributed optical fiber, a fiber Bragg grating demodulator, an infrared thermal imager, a temperature calibration blackbody furnace, and a thermal shield; among them, the fiber Bragg grating demodulator and the infrared thermal imager are both connected to the coal sample reaction chamber, the infrared thermal imager is also connected to the temperature calibration blackbody furnace, and the distributed optical fiber is laid at the bottom of the coal sample reaction chamber in a spiral structure; the fiber Bragg grating demodulator is connected to the distributed optical fiber, and the internal temperature data is collected through the fiber Bragg grating demodulator. The infrared thermal imager scans the surface temperature and generates a pseudo-color temperature field map after being corrected by the temperature calibration blackbody furnace; the coal sample reaction chamber is covered by a thermal shield to isolate the interference of environmental thermal radiation.

[0019] Preferably, the free radical monitoring module includes an electron paramagnetic resonance spectrometer, a microwave resonator, a magnetic field scanning coil, a microwave shield, and a second synchronous control unit; the microwave resonator is arranged inside the electron paramagnetic resonance spectrometer, and the microwave resonator is located in the magnetic field center area of the electron paramagnetic resonance spectrometer; the magnetic field scanning coil is wound around the outside of the microwave resonator, and the area of the microwave resonator and the magnetic field scanning coil is covered by the microwave shield; the coal sample reaction chamber is arranged inside the microwave resonator; the electron paramagnetic resonance spectrometer is connected to the second synchronous control unit for controlling the measurement process.

[0020] Preferably, the active group monitoring module includes a Fourier transform infrared spectrometer, an ultraviolet cut-off filter, a first synchronous control unit, and a temperature control module; among them, the diamond ATR probe of the Fourier transform infrared spectrometer extends into the chamber through a special interface on the right side wall of the coal sample reaction chamber and contacts the surface of the coal sample to collect the infrared spectrum of the coal sample surface; the ultraviolet cut-off filter is arranged in the infrared optical path of the diamond ATR probe returning to the internal detector of the Fourier transform infrared spectrometer to block the ultraviolet stray light entering the optical path; the Fourier transform infrared spectrometer is connected to the first synchronous control unit; the temperature control module is used to maintain the temperature of the probe to avoid temperature drift.

[0021] Preferably, the control unit includes a central controller, a data acquisition card, sensors, a 5G / WiFi communication module, the cloud, and a power management module; among them, the power management module, the central controller, the 5G / WiFi communication module, and the cloud are connected in sequence; the central controller is also connected to the data acquisition card and the sensors in sequence.

[0022] According to the specific embodiments provided by the present invention, the following technical effects of the present invention are disclosed:

[0023] The present invention discloses a multi-parameter real-time monitoring device for the dynamic evolution of coal oxidation under ultraviolet radiation. Through multi-modal collaborative monitoring technology, it can synchronously collect multi-dimensional data such as the release of oxidation gases, temperature field distribution, functional group evolution, and free radical concentration of coal samples under ultraviolet radiation conditions, effectively breaking through the problem of the prior art in real-time monitoring of coal oxidation reactions under ultraviolet radiation. The device combines an ultraviolet radiation module, a gas monitoring module, a heat monitoring module, an active group monitoring module, and a free radical monitoring module to achieve precise and highly time-effective monitoring of the dynamic evolution of coal samples, providing key data support for revealing the mechanism of coal oxidation chain reaction and the spontaneous combustion process. By obtaining various reaction information of coal samples under ultraviolet radiation conditions in real time, the present invention provides a new experimental platform for the research of coal spontaneous combustion prevention and control strategies, has broad application prospects, and is particularly suitable for coal mine safety monitoring and other fields involving coal oxidation and combustion reaction monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0025] Figure 1 It is a schematic structural diagram of a multi-parameter real-time monitoring device for the dynamic evolution of coal oxidation under ultraviolet radiation provided by the present invention;

[0026] Figure 2 It is a schematic structural diagram of the ultraviolet radiation module provided by the embodiment of the present invention;

[0027] Figure 3 It is a schematic diagram of the working principle of the gas monitoring module provided by the embodiment of the present invention;

[0028] Figure 4 It is a schematic diagram of the heat monitoring module provided by the embodiment of the present invention;

[0029] Figure 5 It is a schematic diagram of the working process of the active group monitoring module provided by the embodiment of the present invention;

[0030] Figure 6 It is a schematic structural diagram of the free radical monitoring module provided by the embodiment of the present invention;

[0031] Figure 7 It is a schematic structural diagram of the control unit provided by the embodiment of the present invention;

[0032] Among them, 1 - ultraviolet radiation module, 2 - gas monitoring module, 3 - heat monitoring module, 4 - active group monitoring module, 5 - free radical monitoring module, 6 - coal sample reaction chamber, 7 - control unit, 8 - multi-channel in-situ reaction module, 9 - tunable wavelength LED light source array, 10 - collimating lens group, 11 - light homogenizing plate, 12 - filter switching mechanism, 13 - cooling fan, 14 - light intensity feedback sensor, 15 - power controller, 16 - gas sampling probe, 17 - air pump, 18 - NDIR sensor, 19 - electrochemical sensor, 20 - micro gas chromatograph, 21 - mass flow controller, 22 - drying tube, 23 - waste gas purification unit, 24 - distributed optical fiber, 25 - fiber Bragg grating demodulator, 26 - infrared thermal imager, 27 - temperature calibration blackbody furnace, 28 - thermal shielding cover, 29 - Fourier transform infrared spectrometer, 30 - diamond ATR probe, 31 - ultraviolet cut-off filter, 32 - first synchronous control unit, 33 - temperature control module, 34 - electron paramagnetic resonance spectrometer, 35 - microwave resonator cavity, 36 - magnetic field scanning coil, 37 - microwave shielding cover, 38 - second synchronous control unit, 39 - central controller, 40 - data acquisition card, 41 - sensor, 42 - 5G / WiFi communication module, 43 - cloud, 44 - power management module. Specific embodiments

[0033] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0034] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

[0035] As Figure 1 shown, a multi-parameter real-time monitoring device for the dynamic evolution of coal oxidation under ultraviolet radiation provided by the present invention includes a monitoring unit and a reaction unit. The monitoring unit includes an ultraviolet radiation module 1, a gas monitoring module 2, a heat monitoring module 3, an active group monitoring module 4, a free radical monitoring module 5, and a control unit 7. The reaction unit includes a multi-channel in-situ reaction module 8 and a coal sample reaction chamber 6 provided inside the multi-channel in-situ reaction module 8. The coal sample to be monitored is arranged in the coal sample reaction chamber 6; among them:

[0036] The ultraviolet radiation module 1 is used to generate a controllable ultraviolet radiation field on the surface of the coal sample;

[0037] The gas monitoring module 2 is used to monitor the gas components released during the coal oxidation process in real time;

[0038] The heat monitoring module 3 is used to monitor the temperature distribution inside and on the surface of the coal sample;

[0039] The active group monitoring module 4 is used to track the dynamic evolution of the functional groups on the surface of the coal sample;

[0040] The free radical monitoring module 5 is used to quantitatively analyze the change in the concentration of free radicals during the coal oxidation process;

[0041] The control unit 7 is used to synchronously regulate the operation of each module and integrate multi-modal monitoring data for uploading to the cloud for fusion analysis.

[0042] Specifically, the multi-channel in-situ reaction module 8 serves as a physical container for the coal sample oxidation reaction. It uses special materials (such as quartz) to avoid interfering with the electron paramagnetic resonance (EPR) signal, and at the same time realizes the collaborative work of each module through a multi-channel interface.

[0043] Furthermore, as Figure 2 shown, the ultraviolet radiation module 1 includes an adjustable wavelength LED light source array 9, a collimating lens group 10, a light homogenizing plate 11, a filter switching mechanism 12, a cooling fan 13, a light intensity feedback sensor 14, and a power controller 15;

[0044] The adjustable wavelength LED light source array 9 is composed of deep ultraviolet LEDs (200 - 280 nm), medium ultraviolet LEDs (280 - 315 nm), and near ultraviolet LEDs (315 - 400 nm). The divergence angle is compressed to <5° by the collimating lens group 10, and the light intensity non-uniformity is <5% by the light homogenizing plate 11; the filter switching mechanism 12 has 6 groups of narrowband filters with a half-height width of ±5 nm and switches wavelengths driven by a stepper motor; the light intensity feedback sensor 14 monitors the radiation intensity in real time and adjusts the power controller 15 through a PID algorithm with a light intensity stability of ±2%; the cooling fan 13 dynamically adjusts the rotation speed according to the temperature sensor data to maintain the LED junction temperature ≤40°C;

[0045] Even further, as Figure 3 shown, the gas monitoring module 2 integrates a gas sampling probe 16, a gas pump 17, a non-dispersive infrared (NDIR) sensor 18, an electrochemical sensor 19, a micro gas chromatograph 20, a mass flow controller 21, and an exhaust gas purification unit 23; among them, the gas outlet on the left side wall of the coal sample reaction chamber is connected in series with a gas sampling probe 16, a gas pump 17, a mass flow controller 21, a gas analysis unit, and an exhaust gas purification unit 23 through a pipeline to form a closed gas circuit system with inert gas protection; the gas analysis unit includes an NDIR sensor 18, an electrochemical sensor 19, and a micro gas chromatograph 20 arranged in parallel, and the pipeline between the gas pump 17 and the mass flow controller 21 is a drying tube 22;

[0046] The air pump 17 extracts the gas in the coal sample reaction chamber 6. After dehydration by the drying tube 22, it is distributed to the NDIR sensor 18, the electrochemical sensor 19, and the micro gas chromatograph 20 by the mass flow controller 21. The NDIR sensor 18 detects CO2 and CH4. The electrochemical sensor 19 detects CO. The micro gas chromatograph 20 analyzes C2H4. The waste gas purification unit 23 treats the waste gas through activated carbon adsorption and catalytic oxidation.

[0047] Further, the heat monitoring module 3 includes a distributed optical fiber 24, an optical fiber grating demodulator 25, an infrared thermal imager 26, a temperature calibration blackbody furnace 27, and a thermal shielding cover 28 as Figure 4 shown. Among them, the optical fiber grating demodulator 25 and the infrared thermal imager 26 are both connected to the coal sample reaction chamber 6. The infrared thermal imager 26 is also connected to the temperature calibration blackbody furnace 27. The infrared thermal imager 26 monitors the coal sample reaction chamber 6 through the observation window. The temperature calibration blackbody furnace 27 is used to calibrate the infrared thermal imager 26. The optical fiber grating demodulator 25 is connected to the distributed optical fiber 24. The distributed optical fiber 24 is laid at the bottom of the coal sample reaction chamber 6 in a spiral shape. The temperature data (accuracy ±0.1 °C) is collected at a frequency of 1 Hz through the optical fiber grating demodulator 25. The infrared thermal imager 26 scans the surface temperature every 30 seconds and generates a pseudo-color temperature field map after being corrected by the temperature calibration blackbody furnace 27. The reflectivity of the thermal shielding cover 28 > 95%, isolating the interference of environmental thermal radiation.

[0048] Furthermore, the free radical monitoring module 5 includes an electron paramagnetic resonance spectrometer 34, a microwave resonator 35, a magnetic field scanning coil 36, a microwave shielding cover 37, and a second synchronous control unit 38 as Figure 6 shown. The microwave resonator is arranged inside the electron paramagnetic resonance spectrometer. The microwave resonator is located in the magnetic field center region of the electron paramagnetic resonance spectrometer. The magnetic field scanning coil is wound around the outside of the microwave resonator. The microwave resonator and the magnetic field scanning coil area are covered by the microwave shielding cover. The coal sample reaction chamber is arranged inside the microwave resonator. The electron paramagnetic resonance spectrometer is connected to the second synchronous control unit, which is used to control the measurement process of the electron paramagnetic resonance spectrometer.

[0049] Specifically, the microwave resonator 35 operates in the X band (9.8 GHz), and the Q value > 5000. The magnetic field scanning coil 36 generates a linear scanning magnetic field rate of 0 - 1 T (10 mT / s). The microwave shielding cover 37 suppresses external electromagnetic interference.

[0050] Further, the active group monitoring module includes a Fourier transform infrared spectrometer 29, an ultraviolet cut-off filter 31, a first synchronous control unit 32, and a temperature control module 33 as Figure 5As shown in the figure; among them, the diamond ATR probe 30 of the Fourier transform infrared spectrometer 29 extends into the coal sample reaction chamber 6 through a special interface on the right side wall of the chamber, and it is necessary to make the diamond crystal at the tip of the probe in close physical contact with the surface of the coal sample to collect the infrared spectrum of the coal sample surface (4000 - 600 cm-1, resolution 4 cm-1) at an incident angle of 45°; the ultraviolet cut-off filter 31 is arranged in the infrared light path where the diamond ATR probe 30 returns to the internal detector of the Fourier transform infrared spectrometer 29, and is used to block the ultraviolet stray light with a wavelength < 400 nm that may enter the light path and prevent it from interfering with the operation of the infrared detector; the Fourier transform infrared spectrometer 29 is connected to the first synchronous control unit 32; the temperature control module 33 is used to maintain the probe temperature at 25 ± 0.5 °C to avoid temperature drift.

[0051] Furthermore, as Figure 7 shown in the figure, the control unit includes a central controller 39, a data acquisition card 40, sensors 41, a 5G / WiFi communication module 42, a cloud 43 and a power management module 44; among them, the power management module 44, the central controller 39, the 5G / WiFi communication module 42, and the cloud 43 are connected in sequence; the central controller 39 is also connected to the data acquisition card 40 and the sensors 41 in sequence.

[0052] Specifically, the central controller 39 synchronously triggers each module through the RS485 bus and receives status feedback, with a timing error < 1 ms; the data acquisition card 40 acquires multi-sensor analog signals at a sampling rate of 1 kHz and 24-bit ADC and digitizes them; the sensors 41 integrate temperature, current, and voltage sensors for monitoring each module to monitor the working status of the module in real time; the 5G / WiFi communication module 42 uploads data to the cloud 43 in dual-mode switching, with a transmission delay < 100 ms; the cloud 43 deploys a machine learning platform to achieve data storage, trend prediction, and spontaneous combustion risk assessment; the power management module 44 provides isolated power supplies, including power supplies for the ultraviolet light source (36V / 5A), the EPR spectrometer (±12V / 3A), and the sensors (5V / 12V).

[0053] As Figures 1 - 7As shown, the device includes an ultraviolet radiation module 1, a gas monitoring module 2, a heat monitoring module 3, an active group monitoring module 4, a free radical monitoring module 5 and a control unit 7. The device takes the coal sample reaction chamber 6 as the core carrier, and its multi-channel in-situ reaction module 8 realizes the integration of each module through a three-dimensional orthogonal mechanical interface: structural coupling: the top Z-axis direction adopts a quick-release clamp to connect the uniform light component (10-12) of the ultraviolet radiation module 1, and the bottom is fixed with a distributed optical fiber array of the heat monitoring module 3 by a heat conduction glue; in the X-axis direction, a precision sealing interface provided with an ultraviolet cutoff filter 31 to protect the rear-end infrared spectrometer is used to realize the access detection of the diamond ATR probe 30 of the active group monitoring module 4 to the sample inside the reaction chamber 6; at the same time, the coal sample reaction chamber 6 is entirely accommodated in the microwave resonant cavity 35 of the free radical monitoring module 5, and the integrated structure of the resonant cavity and the reaction chamber can be regarded as being arranged and supported along the Y-axis direction; these together with the ultraviolet radiation module 1 in the Z-axis direction and the heat monitoring module 3 at the bottom constitute a pair of A three-dimensional, multi-parameter in-situ monitoring system for the core reaction area; fluid pathway: the gas outlet on the left wall of the coal sample reaction chamber 6 is connected in series through a PTFE pipeline to the gas pump 17, sensor group 18-20 and exhaust gas purification unit 23 of the gas monitoring module 2, forming a closed-loop gas path system protected by inert gas; electrical interconnection: the sensor signals of each module are fed into the data acquisition card 40 of the control unit 7 through an armored shielded cable, wherein the synchronization control unit realizes the μs-level timing synchronization of the adjustable wavelength LED light source array 9, the magnetic field scanning coil 36 and the Fourier transform infrared spectrometer 29 through hard-line triggering, and the temperature control module 33 shares the PID adjustment bus with the cooling system 13 / 28; communication architecture: the central controller 39 coordinates the subsystems through the CAN bus, and uploads the multimodal data to the cloud 43 via the 5G / WiFi module 42 for fusion analysis.

[0054] The ultraviolet radiation module 1 is located directly above the reaction chamber. Its adjustable wavelength LED light source array 9 is composed of deep ultraviolet (250nm), mid-ultraviolet (300nm) and near ultraviolet (365nm) LEDs. After being collimated by a collimating lens group 10), a uniform light spot (diameter 50mm, light intensity non-uniformity <5%) is formed through a light homogenizer 11. The filter switching mechanism 12 has 6 sets of narrow-band filters (half-height width ±5nm) built in, which are switched by a stepping motor. Figure 2As shown; the light intensity feedback sensor 14 adjusts the power controller 15 in a closed loop through the PID algorithm, with a light intensity stability of ±2%, and the cooling fan 13 dynamically maintains the LED junction temperature ≤ 40°C. In the gas monitoring module 2, the air pump 17 extracts the gas in the coal sample reaction chamber 6. After dehydration by the drying tube 22, it is distributed to the main gas path, the first bypass, and the second bypass by the mass flow controller 21: The main gas path is connected to the NDIR sensor 18 to detect CO2 (0 - 5%) and CH4 (0 - 1000 ppm) in real time. The first bypass is connected to the electrochemical sensor 19 to detect CO in real time. The second bypass is connected to the micro gas chromatograph 20 to analyze C2H4; the waste gas purification unit 23 treats the waste gas through activated carbon adsorption (hydrocarbon removal rate > 95%) and platinum catalytic oxidation (CO conversion rate > 99%), and the emission concentration is CO < 1 ppm and hydrocarbons < 0.1 ppm. The distributed optical fiber 24 of the heat monitoring module 3 is laid at the bottom of the reaction chamber 6 in a spiral structure (pitch 10 mm), and the internal temperature is collected at a frequency of 1 Hz through the fiber Bragg grating demodulator 25 (accuracy ±0.1°C). The infrared thermal imager 26 scans the surface temperature every 30 seconds and generates a pseudo-color temperature field map after calibration by the blackbody furnace 27. The Fourier transform infrared spectrometer 29 of the active group monitoring module 4 dynamically collects characteristic peaks of functional groups such as -OH and -COOH through the diamond ATR probe 30. The ultraviolet cut-off filter 31 blocks ultraviolet interference, and the temperature control module 33 maintains the probe temperature at 25 ± 0.5°C. The electron paramagnetic resonance spectrometer 34 of the free radical monitoring module 5 operates in the X-band (9.8 GHz). The coal sample reaction chamber 6 is arranged inside the microwave resonator 35, and this resonator is located at the magnetic field center of the electron paramagnetic resonance spectrometer 34. The magnetic field scanning coil 36 is arranged around the resonator 35 for superimposing a scanning magnetic field. The scanning range is 0 - 100 mT, the scanning rate is 10 mT / s, and the free radical concentration is scanned once every 5 minutes (sensitivity 1×10 15 spins / G). The microwave shielding cover 37 covers the areas of the microwave resonator 35 and the magnetic field scanning coil 36 to suppress external interference such as Figure 6 shown. The control unit 7 synchronously triggers each module through the central controller 39 (timing error < 1 ms). The data acquisition card 40 acquires signals at a sampling rate of 1 kHz and 24-bit ADC, and the 5G / WiFi module 42 uploads data to the cloud 43 in real time as Figure 7 shown.

[0055] In a specific embodiment 1, 150 - 200 mesh dry coal samples are filled into the coal sample reaction chamber 6. After ensuring good physical contact between the tip of the diamond ATR probe 30 and the coal sample surface, the ultraviolet light source (wavelength 300 nm, light intensity 5 W / m 2)。The air pump 17 of the gas monitoring module 2 extracts gas at a flow rate of 50 mL / min. After dehydration through the drying tube 22, the NDIR sensor 18 monitors the CO2 concentration in real time, the electrochemical sensor 19 detects CO in real time, and the micro gas chromatograph 20 analyzes CH4 and C2H4. When the distributed optical fiber 24 detects that the internal temperature gradient > 3 °C / cm, the infrared thermal imager 26 automatically increases the scanning frequency to 10 s / time. The Fourier transform infrared spectrometer 29 collects -OH peak data at the 0 s, 60 s, and 120 s after the start of ultraviolet radiation, and the electron paramagnetic resonance spectrometer 34 outputs the free radical concentration curve every 5 minutes. When the CO concentration exceeds 50 ppm and the rising rate of the free radical concentration > 8% / min, the central controller 39 triggers an audible and visual alarm and reduces the ultraviolet light intensity to 3 W / m 2 , and at the same time sends a warning signal to the monitoring terminal through the 5G module 42;

[0056] In the specific embodiment 2, the device calibration includes the following steps: Place the standard ultraviolet radiometer probe at the center of the coal sample reaction chamber 6, and adjust the power controller 15 of the ultraviolet radiation module 1 so that the reading error of the light intensity feedback sensor 14 from the standard value < ±1%. Verify the light intensity stability of ±2% in the deep ultraviolet 250 nm, medium ultraviolet 300 nm, and near ultraviolet 365 nm bands, and the wavelength deviation of the filter switching mechanism 12 < ±2 nm; Inject a standard gas containing 500 ppm of CO, 5% of CO2, and 1 ppm of C2H4 into the gas monitoring module 2, and calibrate the zero point and range of the NDIR sensor 18 and the electrochemical sensor 19 (linear error < ±1%), and the retention time repeatability of the micro gas chromatograph 20 is ±0.5%; Arrange a 16-point thermocouple array in the coal sample reaction chamber 6, compare the temperature data of the distributed optical fiber 24 and the infrared thermal imager 26 (spatial consistency error < 0.5%), and calibrate the infrared temperature measurement emissivity (ε = 0.92 ± 0.02) through the temperature calibration blackbody furnace 27; Use a polystyrene standard sheet to calibrate the wavelength accuracy of the Fourier transform infrared spectrometer 29 (deviation < ±2 cm-1), adjust the diamond ATR probe 30 to make it in contact with the sample, and apply appropriate pressure (for example, adjust to 5 N ± 0.5 N) to ensure good optical contact; Inject 1×10 into the microwave resonator 35 in the free radical detection module 5 16The DPPH standard solution of spins / G is used to verify the sensitivity of the electron paramagnetic resonance spectrometer 34 (signal-to-noise ratio > 50); the oscilloscope is used to verify that the timing error of the central controller 39 synchronously triggering each module is < 1 ms, and the transmission delay of the 5G / WiFi module 42 is < 100 ms; the daily maintenance includes replacing the activated carbon filter element of the waste gas purification unit 23 monthly, cleaning the optical elements (collimating lens group 10, homogenizing plate 11, diamond ATR probe 30) with absolute ethanol weekly, and detecting the output stability of the power management module 44 quarterly (ultraviolet light source 36V ± 0.1V, electron paramagnetic resonance spectrometer power supply 12V ± 0.05V).

[0057] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution, in essence, or the part that contributes to the prior art can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0058] In this article, specific examples are used to elaborate on the principles and implementation methods of the present invention. The descriptions of the above embodiments are only used to help understand the method of the present invention and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A multi-parameter real-time monitoring device for the dynamic evolution of coal oxidation under ultraviolet radiation, characterized in that, It comprises a monitoring unit and a reaction unit, wherein the monitoring unit comprises an ultraviolet radiation module, a gas monitoring module, a heat monitoring module, an active group monitoring module, a free radical monitoring module and a control unit, and the reaction unit comprises a multi-channel in-situ reaction module and a coal sample reaction chamber arranged inside the multi-channel in-situ reaction module, wherein the coal sample to be monitored is arranged in the coal sample reaction chamber; wherein: The ultraviolet radiation module is used to generate a controllable ultraviolet radiation field on the surface of the coal sample; The gas monitoring module is used to monitor the gas components released during the coal oxidation process in real time; The heat monitoring module is used to monitor the temperature distribution inside and on the surface of the coal sample; The active group monitoring module is used to track the dynamic evolution of functional groups on the surface of the coal sample; The free radical monitoring module is used to quantitatively analyze the concentration changes of free radicals during the coal oxidation process; The control unit is used to synchronously regulate the operation of each module and integrate multi-modal monitoring data and upload it to the cloud for fusion analysis.

2. The multi-parameter real-time monitoring device for the dynamic evolution of coal oxidation under ultraviolet radiation according to claim 1, characterized in that, The ultraviolet radiation module is arranged directly above the coal sample reaction chamber, and includes an adjustable wavelength LED light source array, a collimating lens group, a light homogenizer, a filter switching mechanism, a cooling fan, a light intensity feedback sensor and a power controller; The adjustable wavelength LED light source array is composed of deep ultraviolet LED, mid-ultraviolet LED and near ultraviolet LED, the divergence angle is compressed by the collimating lens group, and the light intensity non-uniformity is reduced by the light homogenizing sheet; The wavelength is switched through a filter switching mechanism, which has multiple sets of narrow-band filters built in. The wavelength is switched by a stepper motor. The light intensity feedback sensor monitors the radiation intensity in real time and adjusts the power controller in a closed loop through a PID algorithm. The cooling fan is used to maintain the stable operation of the light source.

3. The multi-parameter real-time monitoring device for the dynamic evolution of coal oxidation under ultraviolet radiation according to claim 1, characterized in that, The gas monitoring module includes a gas sampling probe, an air pump, a gas analysis unit, a mass flow controller and an exhaust gas purification unit; wherein the gas outlet on the left side wall of the coal sample reaction chamber is connected in series with the gas sampling probe, the air pump, the mass flow controller, the gas analysis unit and the exhaust gas purification unit in sequence through a pipeline to form a closed-loop gas circuit system protected by an inert gas; the gas analysis unit includes an NDIR sensor, an electrochemical sensor and a micro gas chromatograph arranged in parallel, and the pipeline between the air pump and the mass flow controller is a drying tube; The gas pump extracts gas from the coal sample reaction chamber, and after dehydration through a drying tube, it is distributed to the NDIR sensor, the electrochemical sensor and the micro gas chromatograph by the mass flow controller; the NDIR sensor detects CO2 and CH4, the electrochemical sensor detects CO, and the micro gas chromatograph analyzes C2H4; the exhaust gas purification unit treats the exhaust gas through activated carbon adsorption and catalytic oxidation.

4. The multi-parameter real-time monitoring device for the dynamic evolution of coal oxidation under ultraviolet radiation according to claim 1, characterized in that, The heat monitoring module includes a distributed optical fiber, a fiber Bragg grating demodulator, an infrared thermal imager, a temperature calibration blackbody furnace, and a thermal shielding cover. Among them, the fiber Bragg grating demodulator and the infrared thermal imager are both connected to the coal sample reaction chamber. The infrared thermal imager is also connected to the temperature calibration blackbody furnace. The distributed optical fiber is laid at the bottom of the coal sample reaction chamber in a spiral structure. The fiber Bragg grating demodulator is connected to the distributed optical fiber to collect internal temperature data. The infrared thermal imager scans the surface temperature and generates a pseudo-color temperature field map after being corrected by the temperature calibration blackbody furnace. The coal sample reaction chamber is covered by the thermal shielding cover to isolate environmental thermal radiation interference.

5. The multi-parameter real-time monitoring device for the dynamic evolution of coal oxidation under ultraviolet radiation according to claim 1, characterized in that, The free radical monitoring module includes an electron paramagnetic resonance spectrometer, a microwave resonator, a magnetic field scanning coil, a microwave shielding cover, and a second synchronous control unit. The microwave resonator is arranged inside the electron paramagnetic resonance spectrometer and is located in the magnetic field center region of the electron paramagnetic resonance spectrometer. The magnetic field scanning coil is wound around the outside of the microwave resonator. The area of the microwave resonator and the magnetic field scanning coil is covered by the microwave shielding cover. The coal sample reaction chamber is arranged inside the microwave resonator. The electron paramagnetic resonance spectrometer is connected to the second synchronous control unit to control the measurement process.

6. The multi-parameter real-time monitoring device for the dynamic evolution of coal oxidation under ultraviolet radiation according to claim 1, characterized in that, The active group monitoring module includes a Fourier transform infrared spectrometer, an ultraviolet cut-off filter, a first synchronous control unit, and a temperature control module. Among them, the diamond ATR probe of the Fourier transform infrared spectrometer extends into the chamber through a special interface on the right side wall of the coal sample reaction chamber and contacts the surface of the coal sample to collect the infrared spectrum of the coal sample surface. The ultraviolet cut-off filter is arranged in the infrared optical path when the diamond ATR probe returns to the internal detector of the Fourier transform infrared spectrometer to block the ultraviolet stray light entering the optical path. The Fourier transform infrared spectrometer is connected to the first synchronous control unit. The temperature control module is used to maintain the temperature of the probe to avoid temperature drift.

7. The multi-parameter real-time monitoring device for the dynamic evolution of coal oxidation under ultraviolet radiation according to claim 1, wherein The control unit includes a central controller, a data acquisition card, sensors, a 5G / WiFi communication module, the cloud, and a power management module. Among them, the power management module, the central controller, the 5G / WiFi communication module, and the cloud are connected in sequence. The central controller is also connected to the data acquisition card and the sensors in sequence.

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