A mine tunneling machine anti-condensation adaptive dust control method and system

Abstract

The present application belongs to the field of mine environmental protection and purification control technology, and discloses a mine tunneling machine anti-condensation self-adaptive dust control method and system. The critical condensation point temperature of the roadway environment is solved in real time; before the compressed air back flushing, the waste heat air discharged by the tunneling machine main heat dissipation air cooler is recycled and injected into the air heat exchange jacket outside the gas storage tank by using non-contact heat exchange, the compressed gas in the heat storage tank is pre-heated and the safety superheat margin is dynamically maintained, so as to compensate the transient temperature drop effect generated in the rapid expansion process of high-pressure gas; at the same time, combined with the filter cartridge operating pressure difference and the dynamic load energy level of the source end cutting motor, the back flushing interval and the back flushing pressure are self-adaptively solved. The present application deeply couples "waste heat gas phase thermodynamic temperature control anti-condensation" and "source end dust production energy level prediction", does not need to rely on external thermal management system, reduces the local condensation probability in the pulse back flushing process, and improves the operation stability of the dry dust removal system in the high-hygroscopic salt dust environment.

Description

Technical Field

[0001] This invention relates to the field of environmental protection and purification control technology in mines, and in particular to an adaptive dust control method and system for preventing condensation on mine tunneling machines. Background Technology

[0002] In modern underground mining (such as potash mines and high-temperature, high-humidity deep mines), tunneling and cutting generate massive amounts of high-concentration, ultrafine dust. Because potash dust (mainly composed of potassium chloride and carnallite) has extremely strong water-soluble, hygroscopic, and electrochemically corrosive properties, it releases high concentrations of chloride ions (Cl-) upon contact with moisture. - This leads to severe electrochemical pitting, crevice corrosion, and stress corrosion cracking on the surface of the tunneling machine body, especially high-strength stainless steel and other metal components, significantly shortening the overall lifespan of the machine. Therefore, traditional external spraying for dust control is not feasible in these special mines, necessitating a purely dry tunneling operation process with "zero external spraying" (i.e., no spraying of water mist onto the outside of the machine). Under the rigid constraint of "zero external spraying" and the limitations of the dry operation process, a fully dry vehicle-mounted dust removal system has become one of the important technical solutions to ensure working face safety, visibility, and inhibit electrochemical corrosion of equipment.

[0003] However, when traditional dry dust removal technology is applied to special mines with high temperature and high humidity (such as temperatures greater than 40℃ and relative humidity greater than 85%), it faces the following technical bottlenecks because the physical cooling during cutting provided by external water spray is lost. A large amount of cutting heat is directly injected into the dust removal system along with the high concentration of dust: Localized condensation and bag clogging caused by adiabatic expansion: Dry dust collectors rely on high-pressure compressed air for pulse backflushing cleaning. At the instant the backflushing valve opens, the high-pressure gas is ejected from the nozzle and undergoes violent adiabatic expansion, doing work while simultaneously causing a rapid drop in airflow temperature (i.e., the Joule-Thomson effect). This transient cold airflow directly impacts the already saturated or near-saturated, humid, dust-laden air, easily causing the filter cartridge's inner wall and local microenvironment to rapidly fall below the dew point temperature, resulting in the precipitation of condensate droplets.

[0004] Rapid bag clogging and accelerated corrosion caused by highly hygroscopic dust: Highly hygroscopic fine dust, such as potassium salts, will rapidly deliquesce, physically adhere, and calcify upon contact with condensed water droplets on the filter cartridge surface and inside the housing structure. This forms hardened salt scale that cannot be shaken off by ordinary backflushing, causing the system's air resistance to spike rapidly and the dust removal to fail completely. At the same time, the high concentration of chloride ions released after deliquescence will quickly strip away the passivation layer on the surface of the dust collector housing and stainless steel components, leading to severe corrosion, perforation, and structural failure.

[0005] Traditional methods to prevent bag clogging are energy-intensive and pose safety hazards: To prevent condensation, existing technologies include wrapping the outside of the dust collector housing with an electric heating blanket or adding a high-power onboard electric heater to increase the temperature of the compressed air and the inside of the housing; another method is to use the built-in coil in the dust collector cavity to instantly preheat the back-blowing compressed air. After implementing "zero external water spraying" dry operation for the tunneling machine, the overall heat dissipation load is already extremely high. Using external electric heating would significantly increase the machine's power consumption and heat dissipation pressure. Furthermore, the electric heating elements in the underground gas environment pose a risk of ignition and explosion. On the other hand, the solution of using a dust collector with built-in coils for instantaneous heat exchange has inherent engineering flaws. High-pressure airflow passing through the multi-bend coil piping results in severe pressure loss, weakening the impact energy of pulse cleaning. Moreover, the compressed air can only be heated instantaneously within the coil for a very short time. Significantly increasing the gas temperature requires extremely high heat exchange power. Limited by the dust collector's heat source supply and the coil's heat exchange area, it is difficult to stably reach a temperature that completely avoids condensation under actual operating conditions. Therefore, the dust control and anti-condensation effects of both traditional solutions are not ideal. After eliminating external water spraying, the high-temperature, dust-laden airflow generated during cutting directly enters the dust collection system, placing new demands on the system's thermal and humidity conditions. Summary of the Invention

[0006] To overcome the above-mentioned defects, the present invention provides an adaptive dust control method and system for preventing condensation in mine tunneling machines, which does not rely on any external large-scale special linkages and organically combines waste heat utilization, thermodynamic state conditioning and multi-field collaborative calculation.

[0007] The technical solution of the present invention is as follows: A method for adaptive dust control to prevent condensation in mine tunneling machines, comprising the following steps: Step 1: Obtain the ambient temperature of the tunnel. relative humidity and absolute pressure The critical dew point temperature of the dust-laden air in the current working roadway is dynamically calculated. ; Step 2: Obtain the instantaneous temperature of the compressed air in the air storage tank, and perform non-contact heat exchange conditioning on the compressed air in the air storage tank by recovering the waste heat air discharged from the main cooling air cooler of the tunneling machine, so that the compressed air meets the preset safe overheat margin before injection; use the overheat energy stored before compressed air injection to compensate for the temperature drop generated during the pulse backflushing of compressed air, so that the temperature of the backflushing airflow to the core cleaning area of ​​the filter cartridge group in the dust removal filter box is kept above the critical dew point temperature, and the backflushing airflow is kept in an unsaturated state; Step 3: Online acquisition of instantaneous differential pressure values ​​during the operation of the filter cartridge group in the dust collector filter box. It synchronously receives the operating load power characteristics of the cutting motor from the tunneling machine bus feedback and dynamically calculates the dust generation energy level index at the source. ; Step 4: Based on the collected instantaneous differential pressure values and the source-end dust generation energy level index The pulse backflush time interval is calculated online using a feedforward collaborative adaptive formula. and optimal backflush pressure ; Step 5: When the pulse backflush interval is reached When the electronically controlled pulse valve is activated, compressed air that meets the preset safety overheat margin is injected into the filter cartridge instantaneously. In the state of unsaturated high-pressure hot air flow, high-pressure vibration is performed to suppress the transient moisture absorption and deliquescence of dust on the surface of the filter cartridge, thereby achieving synergistic anti-clogging and dust removal.

[0008] The critical dew point temperature The dynamic solution process is as follows: based on the ambient temperature of the roadway relative humidity and absolute pressure Calculate the actual water vapor partial pressure considering pressure disturbances. : In the formula, The standard atmospheric pressure constant, This is the pressure disturbance correction factor; Substituting the actual water vapor partial pressure into the inverse function equation based on the mapping relationship between saturated vapor pressure and temperature, the critical dew point temperature after considering the pressure correction is calculated. : .

[0009] Instantaneous temperature of compressed air prepared for injection in the air storage tank Before the injection, the preset safe overheat margin is reached as follows: In the formula, To preset a safe overheat margin; The preset safety overheat margin The method for determining it is: combining the backflush pressure. With absolute pressure The theoretical expansion temperature drop during compressed gas injection is obtained based on the adiabatic expansion thermodynamic equation of state. : In the formula, The adiabatic index of the gas. The absolute temperature of the compressed air inside the air tank; This represents the safety margin term for wind speed and transient fluctuations in the tunnel. This indicates the gain from physical moisture absorption compensation.

[0010] The operating load power characteristics of the cutting motor include the instantaneous power of the cutting motor. and the slope of instantaneous temperature rise of the cutting motor Source-end dust generation energy level index The calculation formula is: In the formula, To cut off the rated power of the motor; The weighting coefficient for dust generation under load is set at 1.2 to 1.8. This is the weighting coefficient for dust generation due to frictional heat accumulation, with a value ranging from 0.8 to 1.5.

[0011] The time interval of the pulse backflush The calculation formula is: In the formula, Use the baseline backflush cycle; The preset maximum permissible safe operating pressure differential for the filter cartridge group; This is the differential pressure feedback penalty gain coefficient; The gain coefficient for feedforward adjustment of the dust source's strong heat accumulation; Optimal backflush pressure The calculation formula is: In the formula, As the reference static backflush pressure, This is the differential pressure gain coefficient, with a value ranging from 0.06 MPa to 0.12 MPa. The pressure feedforward gain coefficient for the dust-generating energy level ranges from 0.04 MPa to 0.09 MPa.

[0012] The tunneling machine operates in special high-temperature and high-humidity mines, such as underground potash mines with high static pressure or high wind speed. The anti-clogging dust removal process utilizes a back-blowing airflow maintained above the critical dew point temperature to provide transient unsaturated gas phase heat compensation and airflow disturbance to the potash dust on the filter cartridge surface, breaking the physical critical conditions for salt dust crust formation.

[0013] An adaptive dust control system for preventing condensation in mine tunneling machines, implementing the aforementioned method, is characterized by comprising: A general-purpose dry dust collector actuator includes a dust collector filter housing, an air tank, an electrically controlled pulse valve, and a filter cartridge group blowpipe. The filter cartridge group is arranged inside the dust collector filter housing. The outlet of the air tank is connected to one end of the dust collector filter housing through the filter cartridge group blowpipe, which connects to the built-in filter cartridge group. The other end of the dust collector filter housing is connected to a variable frequency induced draft fan. The electrically controlled pulse valve is installed on the filter cartridge group blowpipe. The sensor and signal acquisition module includes a differential pressure sensor, an ambient temperature and humidity sensor, an absolute pressure sensor, a pressure sensor, a motor status sensor located at the cutting motor, and a cutting motor operating condition monitoring module. The differential pressure sensor is located at both ends of the filter cartridge group to acquire the filter cartridge differential pressure signal. The ambient temperature and humidity sensor and the absolute pressure sensor are located inside the tunnel. The pressure sensor is located inside the air storage tank to detect the instantaneous pressure of the compressed air to be injected. The cutting motor operating condition monitoring module is integrated in the main control cabinet and communicates with the motor status sensor through a CAN bus interface. It reads the motor operating parameters transmitted by the motor status sensor through the CAN bus in real time and analyzes and calculates the instantaneous power and instantaneous temperature rise slope of the cutting motor. The logic control architecture includes a roadway dew point dynamic calculation module, a gas phase superheated state waste heat exchange conditioning module, a source-end dust generation energy level prediction module, and a multi-field coupling parameter adaptive calculation module. The roadway dew point dynamic calculation module calculates the critical dew point temperature based on the collected ambient temperature, relative humidity, and absolute pressure, and sends the critical dew point temperature to the multi-field coupling parameter adaptive calculation module. The source-end dust generation energy level prediction module determines the source-end dust generation energy level index based on the instantaneous output power and instantaneous temperature rise slope of the cutting motor, and sends the source-end dust generation energy level index to the multi-field coupling parameter adaptive calculation module. The multi-field coupling parameter adaptive calculation module generates waste heat conditioning control parameters and backflushing control parameters based on the critical dew point temperature, the source-end dust generation energy level index, and the filter cartridge pressure difference signal, and adjusts the operating status of the gas phase superheated state waste heat exchange conditioning module and the electrically controlled pulse valve.

[0014] The waste heat exchange conditioning module for the superheated gas phase is communicatively connected to the electronically controlled proportional regulating air valve; the hot air collection guide shroud is installed at the exhaust port of the main heat dissipation air cooler of the tunneling machine, and is connected to the air heat exchange jacket covering the outside of the air storage tank through a hot air pipeline equipped with an electronically controlled proportional regulating air valve; a waste heat air flow chamber is formed inside the air heat exchange jacket, and the electronically controlled proportional regulating air valve is used to regulate the flow rate of waste heat air entering the waste heat air flow chamber, so that the waste heat air discharged from the main heat dissipation air cooler exchanges heat with the outer wall of the air storage tank, thereby regulating the thermal state of the compressed air to be injected in the air storage tank; The sensor and signal acquisition module also includes a temperature sensor arranged inside the gas storage tank. The waste heat exchange conditioning module for gas phase superheating receives waste heat conditioning control parameters from the multi-field coupling parameter adaptive calculation module. Combined with the instantaneous temperature of compressed air inside the gas storage tank collected in real time by the temperature sensor, the module adjusts the opening of the electronically controlled proportional regulating air valve to introduce the waste heat air discharged from the main heat dissipation air cooler into the air heat exchange jacket, maintaining... The state of overheating and heat storage.

[0015] The source-end dust generation level prediction module continuously reads and Dynamically calculate the dust generation energy level index at the source end. ; The multi-field coupling parameter adaptive calculation module receives the instantaneous differential pressure value fed back by the differential pressure sensor. and the source-end dust generation energy level index The time interval of pulse backflush is dynamically calculated. With optimal backflush pressure The opening timing and blowing pressure of the electronically controlled pulse valve are controlled.

[0016] The beneficial effects of this invention: Traditional pulse cleaning technology often only focuses on the impact kinetic energy of the airflow, neglecting the transient thermodynamic behavior at the moment of gas release. According to the Joule-Thomson effect, the gas temporarily stored in the gas tank undergoes a violent adiabatic expansion process from high pressure to normal pressure within milliseconds of the pulse valve opening. The gas rapidly does work on the surroundings, causing a significant and extremely difficult-to-predict transient cooling effect in the backflushing airflow at the nozzle outlet and inside the filter cartridge.

[0017] Existing anti-condensation methods (such as external electric heating or instantaneous heat exchange with in-cavity coils) attempt to mitigate this risk, but they often only provide fixed, static heat replenishment and cannot cope with the transient thermodynamic fluctuations caused by the sudden and drastic release of high-pressure gas phase. Especially under "zero external injection" pure dry high-load operation, due to the lack of dynamic feedforward sensing of the dust generation energy level at the source, the static heating not only has extremely high energy consumption, but also easily leads to localized penetrating condensation when faced with the aforementioned transient and drastic expansion and temperature drop due to untimely heat replenishment or insufficient superheat.

[0018] In the high-humidity, high-wind-velocity environment of underground mines, the air in the tunnels has an extremely high moisture content, and the margin between its critical dew point temperature and the current ambient temperature is very small. If unconditioned compressed air is directly sprayed, the sudden drop in temperature caused by adiabatic expansion will instantly and forcibly lower the local micro-environment temperature of the filter cartridge below the dew point temperature, forcing water vapor in the air to condense and form micro-condensates on the surface of the filter cartridge. This is the underlying physical reason why highly hygroscopic salt dust (such as potassium salts) deliquesces, adheres, calcifies, and ultimately leads to filter cartridge failure due to clogging.

[0019] Therefore, this invention takes a different approach, utilizing the high-temperature waste heat air discharged from the main cooling air cooler of the tunneling machine as a natural energy compensation source. Through continuous non-contact heat exchange of hot air in the air heat exchange jacket outside the gas storage tank, the compressed gas inside the tank achieves advanced superheat. This ensures that even after the compressed gas undergoes pulse release, adiabatic expansion, and a necessary rapid temperature drop, its landing temperature (residual heat energy level) remains above the critical dew point temperature of the roadway. Thus, this invention mitigates the risk of localized condensation caused by temperature drop during high-pressure gas release, achieving gas-phase moisture-proof disturbance and efficient vibration removal of highly hygroscopic dust with extremely low engineering energy consumption. Attached Figure Description

[0020] Figure 1 A schematic diagram of the main components of a tunneling machine for installing an anti-condensation adaptive dust control system; Figure 2 This is a schematic diagram of an adaptive dust control system for preventing condensation in mine tunneling machines. Figure 3 The control flowchart is for the adaptive dust control method to prevent condensation on mine tunneling machines.

[0021] In the diagram: 1-Main body; 2-Cutting component; 3-Crawler walking mechanism; 4-Main heat dissipation air cooler; 5-Hot air collection guide shroud; 6-Dust removal filter box; 7-Ambient temperature and humidity sensor and absolute air pressure sensor; 8-Roadway dew point dynamic calculation module; 9-Electrically controlled proportional regulating air valve; 10-Air heat exchange jacket; 11-Air storage tank; 12-Electrically controlled pulse valve; 13-Filter cartridge group blowpipe; 14-Differential pressure sensor; 15-Cutting motor operating condition monitoring module; 16-Source-end dust generation energy level prediction module; 17-Multi-field coupling parameter adaptive calculation module; 18-Air pressure sensor; 19-Temperature sensor; 20-Gas phase superheated state waste heat exchange conditioning module. Detailed Implementation

[0022] like Figure 1 As shown, the tunneling machine includes a body 1, a cutting component 2, a tracked walking mechanism 3, a main heat dissipation air cooler 4, a hot air collection guide shroud 5, and a dust removal and filter box 6; the tracked walking mechanism 3 is installed below the body 1; the cutting component 2 is installed at the front end of the body 1; the main heat dissipation air cooler 4, the hot air collection guide shroud 5, and the dust removal and filter box 6 are assembled on the body 1.

[0023] like Figure 2 As shown, the adaptive dust control system for preventing condensation in mine tunneling machines includes: The general-purpose dry dust removal actuator includes a dust collector filter housing 6, an air tank 11, an electrically controlled pulse valve 12, and a filter cartridge group blowpipe 13; the filter cartridge group is arranged inside the dust collector filter housing; the outlet of the air tank 11 is connected to one end of the dust collector filter housing through the filter cartridge group blowpipe 13, and is connected to the built-in filter cartridge group; the other end of the dust collector filter housing is connected to a variable frequency induced draft fan; the electrically controlled pulse valve 12 is installed on the filter cartridge group blowpipe 13; The sensor and signal acquisition module includes a differential pressure sensor 14, an ambient temperature and humidity sensor, an absolute pressure sensor 7, a pressure sensor 18, a motor status sensor located at the cutting motor, and a cutting motor operating condition monitoring module 15. The differential pressure sensor 14 is located at both ends of the filter cartridge group to acquire the filter cartridge differential pressure signal. The ambient temperature and humidity sensor and the absolute pressure sensor 7 are located inside the roadway. The pressure sensor 18 is located inside the air storage tank 11 to detect the instantaneous pressure of the compressed air to be injected. The cutting motor operating condition monitoring module 15 is integrated into the main control cabinet of the mine tunneling machine anti-condensation adaptive dust removal system. It communicates with the motor status sensor through a CAN bus interface, reads the motor operating parameters transmitted by the motor status sensor through the CAN bus in real time, and analyzes and calculates the instantaneous power and instantaneous temperature rise slope of the cutting motor. The logic control architecture includes a roadway dew point dynamic calculation module 8, a gas phase superheated state waste heat exchange conditioning module 20, a source-end dust generation energy level prediction module 16, and a multi-field coupling parameter adaptive calculation module 17. The roadway dew point dynamic calculation module 8 calculates the critical dew point temperature based on the collected ambient temperature, relative humidity, and absolute pressure, and sends the critical dew point temperature to the multi-field coupling parameter adaptive calculation module 17. The source-end dust generation energy level prediction module 16 determines the source-end dust generation energy level index based on the instantaneous output power of the cutting motor and the instantaneous temperature rise slope of the cutting motor, and sends the source-end dust generation energy level index to the multi-field coupling parameter adaptive calculation module 17. The multi-field coupling parameter adaptive calculation module 17 generates waste heat conditioning control parameters and backflushing control parameters based on the critical dew point temperature, the source-end dust generation energy level index, and the filter cartridge pressure difference signal, and adjusts the operating status of the gas phase superheated state waste heat exchange conditioning module 20 and the electrically controlled pulse valve 12.

[0024] The waste heat exchange conditioning module 20 for the superheated state of the gas phase is communicatively connected to the electronically controlled proportional regulating air valve 9; the hot air collection guide shroud 5 is set at the exhaust port of the main heat dissipation air cooler 4 of the tunneling machine, and is connected to the air heat exchange jacket 10 covering the outside of the air storage tank 11 through the hot air pipeline equipped with the electronically controlled proportional regulating air valve 9; a waste heat air circulation cavity is formed inside the air heat exchange jacket 10, and the electronically controlled proportional regulating air valve 9 is used to regulate the flow rate of waste heat air entering the waste heat air circulation cavity, so that the waste heat air discharged from the main heat dissipation air cooler 4 exchanges heat with the outer wall of the air storage tank 11, thereby regulating the thermal state of the compressed air to be sprayed in the air storage tank 11; The sensor and signal acquisition module also includes a temperature sensor 19 arranged inside the gas storage tank 11; the waste heat exchange conditioning module 20 for gas phase superheated state receives waste heat conditioning control parameters issued by the multi-field coupling parameter adaptive calculation module 17, and combines them with the instantaneous temperature of compressed air inside the gas storage tank 11 collected in real time by the temperature sensor 19, and by adjusting the opening of the electronically controlled proportional regulating air valve 9, introduces the waste heat air discharged from the main heat dissipation air cooler 4 into the air heat exchange jacket 10 to maintain The state of overheating and heat storage.

[0025] The source-end dust generation energy level prediction module 16 continuously reads and Dynamically calculate the dust generation energy level index at the source end. ; The multi-field coupling parameter adaptive calculation module receives the instantaneous micro differential pressure value fed back by the differential pressure sensor 14. and the source-end dust generation energy level index The time interval of pulse backflush is dynamically calculated. With optimal backflush pressure The opening timing and blowing pressure of the electronically controlled pulse valve 12 are controlled.

[0026] like Figure 3 As shown, an adaptive dust control method for preventing condensation in a mine tunneling machine includes the following core steps: Step 1: Obtain the ambient temperature of the tunnel. relative humidity and absolute pressure The critical dew point temperature of the dust-laden air in the current working roadway is dynamically calculated. ; Step 2: Obtain the instantaneous temperature of the compressed air in the air storage tank 11, and perform non-contact heat exchange conditioning on the compressed air by recovering the waste heat air discharged from the main heat dissipation air cooler 4 of the tunneling machine, so that the compressed air meets the preset safe overheat margin before injection; use the overheat energy stored before compressed air injection to compensate for the temperature drop generated during the pulse backflushing of compressed air, so that the temperature of the backflushing airflow to the core area of ​​the dust removal filter box is kept above the critical dew point temperature, and the backflushing airflow is kept in an unsaturated state; Step 3: Online acquisition of instantaneous differential pressure values ​​during the operation of the filter cartridge group in the dust collector filter box. It synchronously receives the operating load power characteristics of the cutting motor from the tunneling machine bus feedback and dynamically calculates the dust generation energy level index at the source. ; Step 4: Based on the collected instantaneous differential pressure values and the source-end dust generation energy level index The pulse backflush time interval is calculated online using a feedforward collaborative adaptive formula. and optimal backflush pressure ; Step 5: When the pulse backflush interval is reached When the filter cartridge is opened, the electronically controlled pulse valve 12 is opened, and compressed air with a preset safety overheat margin is injected into the filter cartridge instantly. In the state of unsaturated high-pressure hot air flow, high-pressure vibration is performed to suppress the transient moisture absorption and deliquescence of dust on the surface of the filter cartridge, thereby achieving synergistic anti-clogging and dust removal.

[0027] As a preferred embodiment, the critical dew point temperature in step one... The dynamic solution process is as follows: based on the ambient temperature of the roadway relative humidity and absolute pressure Calculate the actual water vapor partial pressure considering pressure disturbances. : In the formula, The standard atmospheric pressure constant, This is the pressure disturbance correction coefficient, which is an empirical compensation gain coefficient established for deep, high-wind-speed mine environments, and its value range is limited to 0.015~0.045. As a comprehensive pressure state correction factor, it is used to dynamically eliminate the deviation of basic high static pressure caused by mining depth in deep mines, as well as the drift in dew point calculation caused by transient pressure fluctuations caused by local airflow disturbances.

[0028] Substituting the actual water vapor partial pressure into the inverse function equation based on the mapping relationship between saturated vapor pressure and temperature, the critical dew point temperature after considering the pressure correction is calculated. : .

[0029] As an example, the instantaneous temperature of the compressed air prepared for injection in the air storage tank 11 is... Before the injection, the preset safe overheat margin is reached as follows: In the formula, To pre-set a safe overheat margin, it is preferably limited to 15℃~25℃. This is not only used to compensate for the transient temperature drop caused by the expansion of high-pressure gas, but also to take into account the physical adsorption effect of fine dust as micro-condensation nuclei on water vapor under high dust generation conditions, as well as the premature deliquescence mechanism of highly hygroscopic salt dust in the unsaturated gas phase. By providing a large-scale heat pre-compensation, it ensures dust removal safety in high dust content environments.

[0030] The preset safety overheat margin The method for determining it is: combining the backflush pressure. With absolute pressure The theoretical expansion temperature drop during compressed gas injection is obtained based on the adiabatic expansion thermodynamic equation of state. : In the formula, The adiabatic index of the gas. The absolute temperature of the compressed air inside the air storage tank 11; This represents the safety margin term for wind speed and transient fluctuations in the tunnel. This indicates the gain from physical moisture absorption compensation.

[0031] Preset safe overheat margin The specific method for determining this is: combining the backflush pressure. air pressure in the tunnel environment The theoretical expansion temperature drop during high-pressure gas injection is obtained based on the adiabatic expansion thermodynamic equation of state. : In the formula, The adiabatic index of the gas is taken as 1.4 for dry air. The absolute temperature of the high-pressure compressed air inside the air storage tank 11.

[0032] Superimposed gain from the physical moisture absorption of dust microstructure ; In highly hygroscopic mines such as potash mines, salt dust particles exhibit strong physical hygroscopicity. Even if the macroscopic air temperature is exactly equal to the dew point temperature, the surface of the salt dust will absorb moisture and deliquesce prematurely due to capillary condensation before reaching 100% relative humidity.

[0033] To overcome the critical condition of premature deliquescence of salt dust, it is necessary to introduce physical moisture absorption compensation gain. : For ordinary non-hygroscopic dust: ; For highly hygroscopic salt dust (such as potassium salts and carnallite): based on the critical relative humidity of the salt dust, The temperature is set to 3℃~5℃ to ensure that the surface of the microscopic salt dust particles is always in an absolutely dry gaseous environment.

[0034] Superimposed safety margin terms for roadway wind speed and transient fluctuations ; Considering the high wind speed disturbances in deep mines and the pressure fluctuations at the moment the pulse valve opens, an engineering safety factor is introduced. The value is usually taken as 2℃~5℃.

[0035] Final formula determined: Summing the above three items, the result is calculated under actual tunneling machine operating conditions. It falls exactly within the range of 15℃ to 25℃.

[0036] In one specific embodiment, the operating load power characteristics of the cutting motor include the instantaneous power of the cutting motor. and the slope of instantaneous temperature rise of the cutting motor Source-end dust generation energy level index The calculation formula is: In the formula, To cut off the rated power of the motor; The weighting coefficient for dust generation under load is set at 1.2 to 1.8. This is the weighting coefficient for dust generation due to frictional heat accumulation, with a value ranging from 0.8 to 1.5.

[0037] The physical meaning of this mapping relationship is that when the tunneling machine cuts through high-hardness interbedded rock or salt rock, the motor output power... The temperature rises sharply, and the intense friction between the cutter head and the hard rock causes the motor temperature to rise at a steeper rate. The increase in the combined effect of these two factors can be used to characterize the load enhancement trend and dust generation risk during the cutting process.

[0038] The calculation method for the instantaneous temperature rise slope of the cut motor is as follows: ; express The instantaneous temperature of the cutting motor at any given moment; express The instantaneous temperature of the cutting motor at any given moment; Indicates time difference; In one specific embodiment, the time interval of the pulse backflush The calculation formula is: In the formula, The baseline backflush cycle is set to 60s~90s; The preset maximum permissible safe operating pressure differential for the filter cartridge group; This is the differential pressure feedback penalty gain coefficient, with a value ranging from 15s to 35s; The gain coefficient for strong thermal accumulation of dust source is adjusted by feedforward, and the value range is 5s~15s; Optimal backflush pressure The calculation formula is: In the formula, As the reference static backflush pressure, This is the differential pressure gain coefficient, with a value ranging from 0.06 MPa to 0.12 MPa. The pressure feedforward gain coefficient for the dust-generating energy level ranges from 0.04 MPa to 0.09 MPa.

[0039] When the adaptive backflush time interval is satisfied At that time, the electronically controlled pulse valve 12 is triggered to achieve the optimal backflush pressure. The conditioned, dry hot airflow with a safe overheat margin is instantly injected into the filter cartridge to perform dual-effect dust removal, which combines high-pressure vibration and dynamic anti-condensation and deliquescence inhibition on the surface.

[0040] Taking the underground high-humidity, high-wind-speed potash mine tunneling face as an example, the specific implementation and hardware connection of this method and system are as follows: The waste heat exchange conditioning module 20 for the superheated gas phase is communicatively connected to the electronically controlled proportional regulating air valve 9; the hot air collection guide shroud 5 is connected to the air heat exchange jacket 10 via a hot air circulation pipeline; the electronically controlled proportional regulating air valve 9 is connected in series on the hot air circulation pipeline. Utilizing the exhaust pressure of the tunneling machine's own cooling fan, the high-temperature waste heat air (50℃~70℃) discharged from the main cooling air cooler 4 is introduced into the air heat exchange jacket 10 to perform non-contact waste heat enhancement of the compressed air in the air storage tank 11.

[0041] Status calculation: After power-on, the sensors and signal acquisition module start working, among which the ambient temperature and humidity sensor and absolute pressure sensor 7 collect the current roadway ambient temperature. relative humidity The current real-time absolute air pressure in the deep tunnels Pa. The tunnel dew point dynamic calculation module 8 inputs the above real-time data and sets the standard atmospheric pressure constant. Pa, pressure disturbance correction factor First, calculate the actual water vapor partial pressure considering pressure disturbances. Pa; then, using the mapping equation between the water vapor partial pressure and the saturation temperature, the precise critical dew point temperature under the current operating conditions is automatically calculated. (The calculation result, through the comprehensive pressure state correction factor, fully compensates for the high static pressure reference deviation and transient airflow disturbance in deep roadways. Compared with the traditional calculation dew point of 39.2℃ without pressure correction, it is 0.3℃ higher, thus significantly improving the accuracy of anti-condensation early warning under all wind speed conditions.)

[0042] Waste heat regulation: Initial gas temperature in storage tank 11 (Below dew point temperature). In the case of a superheated gas phase, the waste heat exchange conditioning module 20 determines that the safe overheat margin is insufficient and immediately issues a temperature control command to increase the opening of the electrically controlled proportional regulating valve 9 on the hot air circulation pipeline. A large amount of waste hot air discharged from the main cooling air cooler 4 is introduced into the air heat exchange jacket 10 outside the air storage tank 11, forcibly increasing and maintaining the backflushing compressed air without significantly increasing additional heating energy consumption. At this point, the safe overheat margin Reaching the preset safe zone ( ).

[0043] Operating Condition Sensing and Adjustment: During high-intensity cutting of hard rock by the tunneling machine, the dust generation energy level prediction module 16 at the source detected the cutting motor power. Continuous full load, cutting motor instantaneous temperature rise slope Significantly increased. Simultaneously, differential pressure sensor 14 detected... The Pa rapidly increases from 350 Pa to 1050 Pa. The multi-field coupling parameter adaptive calculation module 17 automatically adjusts the pulse backflush time interval according to the formula. The depth was shortened from the baseline 60s to 18s, and the backflush pressure was increased from 0.4MPa to 0.55MPa.

[0044] Pulse Response: The electrically controlled pulse valve 12 opens efficiently at 18-second intervals, instantly injecting compressed air at 58°C with a safe overheat margin into the filter cartridge. The gas release causes high-pressure adiabatic expansion, performing work and resulting in a transient temperature drop of approximately 16°C. However, due to the pre-existing overheat energy reserve of 18.5°C, the instantaneous temperature (residual heat level) of the backflushing core area remains firmly at 42°C after offsetting this cooling effect. Since this temperature is higher than the roadway critical dew point of 39.5°C, the water vapor in the backflushing airflow and the mixed dust-laden air in the roadway are both in an unsaturated gas phase state, reducing the possibility of condensation on the filter cartridge surface. Highly hygroscopic potassium salt particles are instantly stripped off and peeled off in sheets during the hot air disturbance, helping to reduce the risk of bag clogging caused by salt dust deliquescence and adhesion.

Claims

1. A method for adaptive dust control to prevent condensation in mine tunneling machines, characterized in that, Includes the following steps: Step 1: Obtain the ambient temperature of the tunnel. relative humidity and absolute pressure The critical dew point temperature of the dust-laden air in the current working roadway is dynamically calculated. ; Step 2: Obtain the instantaneous temperature of the compressed air in the air storage tank, and perform non-contact heat exchange conditioning on the compressed air in the air storage tank by recovering the waste heat air discharged from the main cooling air cooler of the tunneling machine, so that the compressed air meets the preset safe overheat margin before injection; use the overheat energy stored before compressed air injection to compensate for the temperature drop generated during the pulse backflushing of compressed air, so that the temperature of the backflushing airflow to the core cleaning area of ​​the filter cartridge group in the dust removal filter box is kept above the critical dew point temperature, and the backflushing airflow is kept in an unsaturated state; Step 3: Online acquisition of instantaneous differential pressure values ​​during the operation of the filter cartridge group in the dust collector filter box. It synchronously receives the operating load power characteristics of the cutting motor from the tunneling machine bus feedback and dynamically calculates the dust generation energy level index at the source. ; Step 4: Based on the collected instantaneous differential pressure values and the source-end dust generation energy level index The pulse backflush time interval is calculated online using a feedforward collaborative adaptive formula. and optimal backflush pressure ; Step 5: When the pulse backflush interval is reached When the electronically controlled pulse valve is activated, compressed air that meets the preset safety overheat margin is injected into the filter cartridge instantaneously. In the state of unsaturated high-pressure hot air flow, high-pressure vibration is performed to suppress the transient moisture absorption and deliquescence of dust on the surface of the filter cartridge, thereby achieving synergistic anti-clogging and dust removal.

2. The adaptive dust control method for preventing condensation in a mine tunneling machine according to claim 1, characterized in that, The critical dew point temperature The dynamic solution process is as follows: based on the ambient temperature of the roadway relative humidity and absolute pressure Calculate the actual water vapor partial pressure considering pressure disturbances. : In the formula, The standard atmospheric pressure constant, This is the pressure disturbance correction factor; Substituting the actual water vapor partial pressure into the inverse function equation based on the mapping relationship between saturated vapor pressure and temperature, the critical dew point temperature after considering the pressure correction is calculated. : 。 3. The adaptive dust control method for preventing condensation in a mine tunneling machine according to claim 1, characterized in that, Instantaneous temperature of compressed air prepared for injection in the air storage tank Before the injection, the preset safe overheat margin is reached as follows: In the formula, To preset a safe overheat margin; The preset safety overheat margin The method for determining it is: combining the backflush pressure. With absolute pressure The theoretical expansion temperature drop during compressed gas injection is obtained based on the adiabatic expansion thermodynamic equation of state. : In the formula, The adiabatic index of the gas. The absolute temperature of the compressed air inside the air tank; This represents the safety margin term for wind speed and transient fluctuations in the tunnel. This indicates the gain from physical moisture absorption compensation.

4. The adaptive dust control method for preventing condensation in a mine tunneling machine according to claim 1, characterized in that, The operating load power characteristics of the cutting motor include the instantaneous power of the cutting motor. and the slope of instantaneous temperature rise of the cutting motor Source-end dust generation energy level index The calculation formula is: In the formula, To cut off the rated power of the motor; The weighting coefficient for dust generation under load is set at 1.2 to 1.

8. This is the weighting coefficient for dust generation due to frictional heat accumulation, with a value ranging from 0.8 to 1.

5.

5. A method for adaptive dust control to prevent condensation in a mine tunneling machine according to claim 1 or 4, characterized in that, The time interval of the pulse backflush The calculation formula is: In the formula, Use the baseline backflush cycle; The preset maximum permissible safe operating pressure differential for the filter cartridge group; This is the differential pressure feedback penalty gain coefficient; The gain coefficient for feedforward adjustment of the dust source's strong heat accumulation; Optimal backflush pressure The calculation formula is: In the formula, As the reference static backflush pressure, This is the differential pressure gain coefficient, with a value ranging from 0.06 MPa to 0.12 MPa. The pressure feedforward gain coefficient for the dust-generating energy level ranges from 0.04 MPa to 0.09 MPa.

6. The adaptive dust control method for preventing condensation in a mine tunneling machine according to claim 1, characterized in that, The tunneling machine operates in special high-temperature and high-humidity mines, such as underground potash mines with high static pressure or high wind speed. The anti-clogging dust removal process utilizes a back-blowing airflow maintained above the critical dew point temperature to provide transient unsaturated gas phase heat compensation and airflow disturbance to the potash dust on the filter cartridge surface, breaking the physical critical conditions for salt dust crust formation.

7. An adaptive dust control system for preventing condensation in a mine tunneling machine, implementing the method of any one of claims 1-6, characterized in that, include: The general-purpose dry dust removal actuator includes a dust removal filter box (6), an air tank (11), an electrically controlled pulse valve (12), and a filter cartridge group blow pipe (13); the filter cartridge group is arranged inside the dust removal filter box (6); the outlet of the air tank (11) is connected to one end of the dust removal filter box (6) through the filter cartridge group blow pipe (13), and is connected to the built-in filter cartridge group; the other end of the dust removal filter box (6) is connected to a variable frequency induced draft fan; the electrically controlled pulse valve (12) is installed on the filter cartridge group blow pipe (13); The sensor and signal acquisition module includes a differential pressure sensor (14), an ambient temperature and humidity sensor and an absolute air pressure sensor (7), an air pressure sensor (18), a motor status sensor arranged at the cutting motor, and a cutting motor operating condition monitoring module (15). The differential pressure sensor (14) is set at both ends of the filter cartridge group to acquire the filter cartridge differential pressure signal. The ambient temperature and humidity sensor and the absolute air pressure sensor (7) are set in the roadway. The air pressure sensor (18) is set in the inner cavity of the air storage tank (11) to detect the instantaneous pressure of the compressed air to be sprayed. The cutting motor operating condition monitoring module (15) is integrated in the main control cabinet and communicates with the motor status sensor through the CAN bus interface. It reads the motor operating parameters transmitted by the motor status sensor through the CAN bus in real time and analyzes and calculates the instantaneous power and instantaneous temperature rise slope of the cutting motor. The logic control architecture includes a roadway dew point dynamic calculation module (8), a gas phase superheated state waste heat exchange conditioning module, a source-end dust generation energy level prediction module (16), and a multi-field coupling parameter adaptive calculation module (17). The roadway dew point dynamic calculation module (8) calculates the critical dew point temperature based on the collected ambient temperature, relative humidity, and absolute pressure; and sends the critical dew point temperature to the multi-field coupling parameter adaptive calculation module (17). The source-end dust generation energy level prediction module (16) calculates the critical dew point temperature based on the collected ambient temperature, relative humidity, and absolute pressure. The instantaneous output power of the cutting motor and the instantaneous temperature rise slope of the cutting motor determine the source-end dust generation energy level index, and send the source-end dust generation energy level index to the multi-field coupling parameter adaptive calculation module (17); the multi-field coupling parameter adaptive calculation module (17) generates waste heat conditioning control parameters and backflushing control parameters according to the critical dew point temperature, the source-end dust generation energy level index and the filter cartridge pressure difference signal, and adjusts the operating status of the gas phase superheated state waste heat exchange conditioning module (20) and the electric control pulse valve (12).

8. The adaptive dust control system for preventing condensation in mine tunneling machines according to claim 7, characterized in that, The waste heat exchange conditioning module (20) for superheated gas phase is connected to the electronically controlled proportional regulating air valve (9) in communication. The hot air collection guide hood (5) is set at the exhaust port of the main heat dissipation air cooler (4) of the tunneling machine and is connected to the air heat exchange jacket (10) covering the outside of the air storage tank (11) through the hot air pipeline equipped with the electronically controlled proportional regulating air valve (9). The air heat exchange jacket (10) forms a waste heat air flow chamber inside. The electronically controlled proportional regulating air valve (9) is used to regulate the flow rate of waste heat air entering the waste heat air flow chamber so that the waste heat air discharged from the main heat dissipation air cooler (4) exchanges heat with the outer wall of the air storage tank (11) to regulate the thermal state of the compressed air to be sprayed in the air storage tank (11). The sensor and signal acquisition module also includes a temperature sensor (19) arranged inside the gas storage tank (11); the gas phase superheated state waste heat exchange conditioning module (20) receives the waste heat conditioning control parameters issued by the multi-field coupling parameter adaptive calculation module (17), and combines the instantaneous temperature of the compressed air in the gas storage tank (11) collected in real time by the temperature sensor (19), and by adjusting the opening of the electronically controlled proportional regulating air valve (9), introduces the waste heat air discharged from the main heat dissipation air cooler (4) into the air heat exchange jacket (10) to maintain The state of overheating and heat storage.

9. The adaptive dust control system for preventing condensation in mine tunneling machines according to claim 7, characterized in that, The source-end dust generation energy level prediction module (16) continuously reads and Dynamically calculate the dust generation energy level index at the source end. ; The multi-field coupling parameter adaptive calculation module (17) receives the instantaneous differential pressure value fed back by the differential pressure sensor (14). and the source-end dust generation energy level index The time interval of pulse backflush is dynamically calculated. With optimal backflush pressure The opening timing and blowing pressure of the electronically controlled pulse valve (12) are controlled.

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