Mine parallel boosting fire extinguishing method

Abstract

The present application relates to the technical field of mine safety, in particular to a mine parallel boosting fire extinguishing method. It comprises parallel boosting, nitrogen injection inerting, physical plugging and intelligent monitoring. In the present application, fan-wind window combined pressure regulation is used to realize equivalent boosting of the working face, actively inhibit the spread of harmful gases in the fire area, and provide strong pneumatic power for nitrogen injection, improving the inerting efficiency; synchronous ground plugging and corner plugging, which is effectively complementary to the parallel boosting and nitrogen injection measures, is strong in system and stable and reliable in effect; and through real-time monitoring of atmospheric environmental parameters, dynamic calculation and automatic adjustment of the boosting value, taking the CO concentration at the key position as the final constraint condition for linkage regulation and control, an intelligent closed-loop control is formed, which significantly improves the predictability and response speed of fire hazards, and fundamentally solves the outstanding problems of the existing methods, such as response lag, and inability to meet the high-efficiency and safe production requirements of modern mines.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mine safety, in particular to a mine parallel boosting fire extinguishing method. BACKGROUND

[0002] Mine fire prevention and extinguishing is a technical system for preventing and treating mine fires such as fires in various places underground and ground fires near the wellhead, covering the prevention and disposal of internal and external causes of fire, including direct fire extinguishing method, isolation fire extinguishing method and combined fire extinguishing method.

[0003] At present, the fire prevention and control of the goaf in the mine mainly relies on traditional means such as ventilation system adjustment, water injection or grouting. However, during the operation of the coal mining face, due to the dynamic changes of the mine ventilation network, the development of surface fissures in shallow buried coal seams and the complexity of the air leakage channels in the goaf, the traditional methods are difficult to continuously and stably inhibit the spread of the fire area or the gas seepage. Ventilation adjustment often operates through a single fan or air window, which easily leads to fluctuations in the total air volume of the mine, thereby exacerbating the risk of air leakage or fire spread; water injection and grouting measures are limited by uneven fluid diffusion and cannot effectively inert the entire fire area. Therefore, it is crucial to build an integrated and self-adaptive strong fire prevention and extinguishing system to improve the reliability of mine fire prevention and control, especially under high-risk conditions such as shallow depth.

[0004] In the prior art, the methods for preventing and controlling mine fires mainly include local ventilation pressure regulation, inert gas injection and fissure plugging. These methods have limitations: ventilation pressure regulation relies on manual experience to adjust the fan or air window, which makes it difficult to achieve precise balance of the working face pressure and energy, and easily interferes with the overall stability of the mine ventilation; nitrogen injection and other inerting technologies can reduce oxygen concentration, but lack effective aerodynamic support, and nitrogen dispersion is insufficient, resulting in low inerting efficiency of the fire area; surface fissures and corner plugging often use passive material filling, and the plugging effect is greatly affected by the construction quality, and cannot dynamically adapt to the changes in the air leakage path caused by mining. In addition, the existing monitoring system mainly relies on single sensors (such as CO detection) for threshold alarm, and cannot integrate multi-parameter real-time calculation and linkage control, which makes the fire prevention and control process response lag and the control precision low, and cannot meet the needs of fire prevention and control under complex conditions. SUMMARY

[0005] The purpose of the present application is to solve the problem of response lag in the fire extinguishing process caused by the single prevention and control method of the existing mine fire prevention and extinguishing, which cannot meet the needs of fire prevention and control.

[0006] The purpose of the present application is to provide a mine parallel boosting fire extinguishing method, which integrates parallel boosting, nitrogen injection inerting, physical plugging and intelligent monitoring to become a comprehensive fire prevention and extinguishing system with synergistic effect, thereby improving the reliability of mine fire prevention and control.

[0007] In order to achieve the above-mentioned purpose, the present application aims to provide a mine parallel boosting fire extinguishing method, comprising the following steps:

[0008] Step S1: installing a pressure regulating fan in the air inlet gallery of the coal mining face, and installing an automatically adjustable air window in the air return gallery to form a fan-air window combined pressure regulating system;

[0009] Synchronously blocking the air inlet corner and the air return corner of the coal mining face, and blocking the surface fissure above the goaf;

[0010] Step S2: obtaining the absolute pressure, temperature, humidity and elevation parameters of the two places near the surface fissure and the outside of the underground air return roadway in real time, and then dynamically calculating the target boosting value based on the above-mentioned parameters;

[0011] Then, the fan-air window combined pressure regulating system adjusts the opening area of the air window to form a stable equivalent boosting field in the coal mining face area;

[0012] Step S3: after the stable establishment of the equivalent boosting field, injecting nitrogen into the goaf, so that the nitrogen is dispersed to the deep part of the goaf, the connected old roadway and the surface fissure under the driving of the aerodynamic force generated by the equivalent boosting field, and the fire area is inerted;

[0013] Step S4: monitoring the CO concentration of the key positions of the air return corner and / or the air return roadway in real time;

[0014] The target boosting value calculated in step S2 is used as the control reference, and the monitored CO concentration is used as the linkage control constraint condition, and when the CO concentration is abnormal, the operation parameters of the fan-air window combined pressure regulating system are automatically fine-tuned.

[0015] As a further improvement of the technical solution, in step S1, two pressure regulating fans are installed in parallel in the air inlet gallery, and the fan air outlet direction is ensured to be consistent with the air flow direction of the roadway.

[0016] As a further improvement of the technical solution, in step S1, the automatically adjustable air window is a louvered air window controlled by an electric push rod.

[0017] As a further improvement of the technical solution, in step S1, the air inlet corner and the air return corner are blocked by a high molecular material or a sandbag isolation wall.

[0018] As a further improvement of the technical solution, in step S2, the pressure difference between the surface and the underground monitoring points is calculated, and the temperature, humidity and elevation parameters are introduced for compensation to determine the pressure value required to make the pressure difference between the surface and the underground monitoring points tend to zero as the target boosting value.

[0019] As a further improvement of the technical solution, in step S2, a multi-parameter sensor for monitoring absolute pressure, temperature and humidity is arranged near the surface fissure and at the outer opening of the downhole return air roadway.

[0020] As a further improvement of the technical solution, the target boost value calculation formula is as follows:

[0021]

[0022] In the formula, is the target boost value, is the absolute atmospheric pressure at the surface fissure, is the absolute atmospheric pressure at the outer opening of the downhole return air roadway, is the acceleration of gravity, is the specific gas constant of dry air, is the absolute pressure at the surface fissure, is the absolute pressure at the outer opening of the downhole return air roadway, is the elevation of the surface fissure, is the elevation of the outer opening of the downhole return air roadway, is the temperature at the surface fissure, is the temperature at the outer opening of the downhole return air roadway, is the specific humidity at the surface fissure, is the specific humidity at the outer opening of the downhole return air roadway.

[0023] As a further improvement of the technical solution, in step S4, a sensor for monitoring CO concentration is arranged at the return air corner and the return air roadway.

[0024] As a further improvement of the technical solution, in step S4, a CO concentration early warning threshold is preset.

[0025] When the monitored CO concentration exceeds the above-mentioned early warning threshold, an additional boost increment is added to the target boost value based on the linkage control, and the boost increment is 10-30 Pa.

[0026] In the present application, a fan-wind window combined pressure regulating system is constructed and the corner is plugged and the surface is plugged; then, the target boost value is dynamically calculated based on the real-time monitored atmospheric environmental parameters, the parallel boost of the working face is realized through intelligent adjustment of the wind window, the spread of harmful gas is inhibited and the pneumatic force for nitrogen injection is provided under the premise of not affecting the total air volume; then, nitrogen is injected into the goaf under the assistance of the boost field, efficient inertization is realized; finally, CO concentration is introduced as a feedback signal to linkingly fine-tune the boost value, forming an intelligent closed-loop control. The present application has strong system, solves the problems of response lag and poor synergy of the traditional method, and is especially suitable for fire prevention and control under complex conditions such as shallow depth coal seam, and the effect is stable and reliable.

[0027] Compared with the prior art, the present application has the following beneficial effects:

[0028] In the mine parallel pressure boosting fire prevention and extinguishing method, the fan and the air window are combined to realize equivalent pressure boosting of the working face, the spread of harmful gas in the fire area is actively inhibited without disturbing the normal ventilation of the mine, and strong pneumatic power is provided for nitrogen injection, which significantly improves the inerting efficiency; the surface plugging and the corner plugging are simultaneously performed, which physically cuts off the key air leakage channel, and effectively complements the parallel pressure boosting and nitrogen injection measures, and the system is strong, the effect is stable and reliable, and it is especially suitable for complex conditions such as shallow depth coal seams;

[0029] Furthermore, by dynamically calculating and automatically adjusting the pressure boosting value in real time according to the atmospheric environment parameters, the lag of the traditional method depending on fixed parameters and being unable to respond to environmental changes is overcome; further, the CO concentration at the key position is taken as the final constraint condition of the linkage regulation and control, an intelligent closed-loop control is formed, the predictability and response speed of the fire hazard are significantly improved, and the outstanding problems that the existing method has response lag and cannot meet the efficient and safe production demand of modern mines are fundamentally solved. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 The method steps of the present application are described. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0032] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0033] Please refer to Figure 1 The present embodiment aims to provide a mine parallel pressure boosting fire prevention and extinguishing method, which comprises the following steps:

[0034] Step S1: two pressure regulating fans are installed in parallel in the intake airway of the coal mining face, and the fan air outlet direction is ensured to be consistent with the air flow direction of the roadway, an automatically adjustable air window is installed in the return airway, and a fan-air window combined pressure regulating system is formed.

[0035] It is worth noting that the automatically adjustable air window is a louvered air window controlled by an electric push rod.

[0036] The above-mentioned intake corner and return corner of the coal mining face are blocked by synchronously using a polymer material or sandbags to build a partition wall, and the surface fissures above the goaf are blocked to preliminarily block the air leakage channels.

[0037] Through the accurate installation of the fan-air window combination in step S1, a reliable hardware foundation is provided for the implementation of accurate "parallel pressure boosting"; through the physical blocking of the intake and return corners, which are the main air leakage sources, and the timely backfilling of the surface fissures, the oxygen supply of the goaf is significantly reduced, and the conditions for spontaneous combustion of residual coal are inhibited from the source, creating favorable boundary conditions for subsequent technical measures. That is, through the cooperation of the basic air leakage blocking and the subsequent parallel pressure boosting and nitrogen injection measures, the effect of parallel pressure boosting is avoided due to too many air leakage channels and the weakening of the effect of parallel pressure boosting or the large loss of injected nitrogen gas.

[0038] Step S2: multi-parameter sensors for monitoring absolute pressure, temperature and humidity are arranged near the surface fissures and at the outer opening of the underground return airway to obtain the absolute pressure, temperature, humidity and elevation parameters of the two places in real time, and then the target pressure boost value is calculated dynamically online based on the above parameters. Specifically, the pressure difference between the surface and underground monitoring points is calculated, and the temperature, humidity and elevation parameters are introduced for compensation to determine the pressure value required to make the pressure difference between the surface and underground monitoring points tend to zero as the target pressure boost value.

[0039] The significance of the target pressure boost value is to balance the pressure between the surface fissures (point A) and the outer opening of the underground return airway (point B), thereby eliminating the driving force of the air leakage channel. Therefore, the calculation formula of the target pressure boost value can be expressed as follows:

[0040]

[0041]

[0042] In the formula, is the target pressure boost value (unit: Pascal, Pa) that needs to be calculated online, is the absolute atmospheric pressure at the surface fissures, is the absolute atmospheric pressure at the outer opening of the underground return airway, is the pressure difference between the surface fissures and the outer opening of the underground return airway, is the air density (unit: kg / m3) at the surface fissure, is the air density (unit: kg / m3) at the return airway outside mouth, is the gravity acceleration, is the altitude (unit: m) at the surface fissure, is the altitude (unit: m) at the return airway outside mouth;

[0043] The above , is not a direct measurement value, but is calculated in real time, (The formula is , is the absolute atmospheric pressure (unit: Pa) at the measurement point, is the specific gas constant of dry air (about 287 J / (kg·K)), is the virtual temperature (unit: K), which is the humidity-corrected value of the actual temperature, and the formula for calculating the virtual temperature is , is the actual measured temperature (K), is the specific humidity (the mass of water vapor contained in unit mass of air). The virtual temperature is introduced to more accurately calculate the density of wet air)

[0044] Therefore, by substituting, we get

[0045]

[0046] That is

[0047] In the formula, is the temperature at the surface fissure, is the temperature at the return airway outside mouth, is the specific humidity at the surface fissure, is the specific humidity at the return airway outside mouth.

[0048] Subsequently, the fan-ventilator combined pressure regulating system intelligently adjusts the opening and closing area of the ventilator to form a stable equivalent pressure field in the coal mining face area, realizing parallel pressure increase in the operation section without changing the total air volume of the mine.

[0049] Through the setting of step S2, the shortcomings of fixed setting value in traditional pressure equalization technology, unable to respond to environmental disturbances such as changes in atmospheric pressure, are overcome, realizing real-time online calculation and dynamic tracking adjustment of the pressure increase value, ensuring the long-term stability of the parallel pressure increase effect. And through multi-parameter sensing and precise algorithm, precise compensation against the influence of natural wind pressure is realized, making the parallel pressure increase control more scientific and accurate.

[0050] In addition, the "parallel pressure increase" feature ensures that while increasing the working face pressure energy, the total mine air volume and the air volume of each branch are not changed, thus avoiding secondary risks such as air volume disturbances or gas accumulation in other areas caused by pressure regulation.

[0051] Step S3: After the equivalent pressure field is established stably, nitrogen is injected into the goaf. Driven by the aerodynamic force generated by the equivalent pressure field, the nitrogen diffuses into the depth of the goaf, the connected old roadways, and the surface fissures, thus inerting the fire zone.

[0052] Compared with the traditional nitrogen injection method that relies solely on diffusion, step S3 uses pneumatically assisted nitrogen injection, which greatly increases the nitrogen delivery distance and diffusion speed, enabling the inerting gas to effectively reach the source of the air leakage channel and significantly shorten the fire extinguishing cycle. At the same time, under the effect of the "pressure barrier" formed by parallel pressurization, the injected nitrogen and harmful gases (such as CO) generated in the goaf are effectively "sealed" deep in the goaf, making it difficult to leak into the working face space and ensuring operational safety.

[0053] Step S3, which involves plugging leaks in step S1, and step S2, which involves parallel pressurization, are closely integrated to form a highly efficient fire prevention and extinguishing mechanism that combines plugging, pressurization, and injection, thereby making the most effective use of nitrogen resources.

[0054] Step S4: Similarly, sensors for monitoring CO concentration are installed in the return air corner and return air alley to monitor the CO concentration at key locations in the return air corner and / or return air alley in real time.

[0055] The target boost value calculated in step S2 is used as the basic control benchmark, and the monitored CO concentration is used as the linkage control constraint condition, specifically: preset CO concentration early warning threshold;

[0056] When the monitored CO concentration exceeds the aforementioned warning threshold, the linkage control adds an additional pressure increment to the target pressure increase value. This pressure increment can be slightly modified based on historical data or more complex models (such as those considering airflow resistance characteristics) to further improve control accuracy. In this invention, the pressure increment is preferably 10-30 Pa, so that when the CO concentration is abnormal, the operating parameters of the fan-ventilation combined pressure regulation system are automatically fine-tuned to achieve dynamic optimization of fire prevention and extinguishing effects.

[0057] Step S4 introduces a closed-loop control mechanism with the key gas concentration as the feedback signal, providing important safety redundancy for dynamic pressure rise calculation. When theoretical calculations deviate due to extreme weather or sudden geological conditions, the gas concentration feedback can serve as the final safety line, ensuring foolproof prevention and control. Furthermore, by responding early to changes in CO concentration, potential fire hazards can be eliminated in their infancy, achieving "early detection and early response" in fire prevention and extinguishing work, and improving the predictability and accuracy of mine safety.

[0058] In summary, the system reads sensor data in real time: absolute pressure, temperature, humidity, and known elevation at points A (at the surface fissure) and B (outside the return airway). The central monitoring system uses the above-mentioned target pressure increase formula to calculate the target pressure increase required. The system uses this target pressure increase as a set value to automatically adjust the opening of the air window in the return airway through a PID control algorithm, so that the measured value of the differential pressure sensor installed on both sides of the pressure regulating facility stabilizes around the target pressure increase;

[0059] At the same time, the system continuously monitors the CO concentration at key points such as the return air corner and return air flow. If the CO concentration abnormally increases, it indicates that the current target pressure increase is not sufficient to completely suppress the outflow of harmful gases, and the system will automatically increase the target pressure increase by an increment, forming a closed-loop control until the environment is safe.

[0060] The specific implementation steps of the embodiment of the present application are as follows:

[0061] Step one, in the intake airway of the coal mining face, a stable roadway section is installed with two mine explosion-proof extraction type counter-rotating local fans as pressure regulating fans at a certain distance from the working face (usually near the roadway outside). The fan outlet is connected to the roadway through a rigid air duct to ensure that the air flow direction is consistent with the main air flow. At a suitable position in the return airway, a louver type adjustable air window controlled by an electric push rod is installed, and the area of the air window can be remotely adjusted steplessly. The fan and the air window are connected to the central monitoring system through a mine explosion-proof and intrinsic safety type control box.

[0062] At the intake air corner and the return air corner, a high-molecular expansion sealing material (such as polyurethane foam) is used in combination with woven bags filled with crushed coal or sandbags to build a sealing wall that is in close contact with the roof, floor and two sides of the roadway. The sealing body should have a certain shrinkability to adapt to the roof subsidence and ensure the sealing effect.

[0063] As the working face advances, the geological survey personnel regularly mark the location of the newly formed surface fissures. Using excavators, bulldozers and other equipment, the fissures are rammed and compacted with loess, fly ash or special composite materials, and the areas directly above the intake and return airways with large fissure width that may form the main air leakage channel are focused on.

[0064] Step two, a weather station is set up near the representative fissure group on the surface above the goaf (avoiding direct tread areas) to monitor the absolute pressure, temperature and humidity at the surface fissure. In the return airway outside the coal mining face where the pressure increase is to be implemented (near the connection with the return airway of the mining area), a stable roadway section is installed with the same type of mine intrinsic safety type pressure, temperature and humidity sensors to monitor the absolute pressure, temperature and humidity at the return airway outside the mine. At the same time, the elevation of the surface monitoring point is obtained through geological surveying or GPS positioning.

[0065] A central monitoring system with a built-in algorithm module dynamically calculates the target pressure boost value based on real-time data collected. The calculation principle is to bring the pressure difference between the surface fissure and the outer entrance of the underground return airway to near zero, thus eliminating air leakage. The core algorithm calculates the weight difference of the air column between the two monitoring points and performs temperature and humidity compensation, as shown in the following formula:

[0066]

[0067] In the formula, For the target boost pressure value, This represents the absolute atmospheric pressure at the surface fissure. This refers to the absolute atmospheric pressure at the outer entrance of the underground return airway. It is the acceleration due to gravity. Let be the specific gas constant of dry air. This refers to the absolute pressure at the surface fissure. The absolute pressure at the entrance of the underground return airway. This is the elevation at the surface fissure. This is the elevation of the outer entrance of the underground return airway. Temperature at the surface fissure. The temperature at the outside of the underground return airway. The specific humidity at the surface fissures. The humidity level is measured at the outer entrance of the underground return airway.

[0068] The system refreshes automatically at a preset frequency (e.g., every 3 hours). The target value. The system will The target value is sent to the window controller. The controller compares the measured values ​​from the differential pressure sensors installed on both sides of the damper. Actual measurement and The goal is to use a PID algorithm to drive an electric actuator to adjust the angle of the windshield blades, thereby changing the ventilation resistance until... Actual test results showed stability at Within the acceptable error range. This process achieves "parallel pressure increase" of the working face area relative to the surface environment, meaning that the pressure energy at all points within the working face increases by the same value while the airflow remains unchanged.

[0069] Step 3: After the parallel pressurization system is running stably, high-purity nitrogen (concentration ≥97%) is injected through the nitrogen injection pipeline pre-buried in the goaf (usually laid on one side of the intake air roadway, with the pipeline outlet extending a certain distance into the goaf).

[0070] At this time, due to the parallel booster system establishing a high pressure area in the working face area relative to the deep goaf and the ground, the pressure difference provides strong pneumatic power for the nitrogen transport. Under the dual action of external pressure difference driving and self diffusion effect, the nitrogen is no longer blindly spread, but is actively and directionally "pushed" to the deep goaf, the upper connected old roadway and the ground fissure direction, so as to realize the accurate coverage of the target area.

[0071] Step four, at the key positions such as the side of the return air corner isolation wall close to the working face, the return air roadway of the working face 10-20 meters away from the corner, etc., install the mine intrinsic safety type CO sensor and O2 sensor for 24 hours uninterrupted monitoring.

[0072] The central monitoring system sets double regulation thresholds. Under normal circumstances, the system regulates and controls based on the target calculated in step two. Once the CO concentration of the return air corner is monitored to exceed the primary warning value (such as 24 ppm), the system will automatically start the linkage regulation program, slightly increase the target pressure value (for example, increase by 10-30 Pa) based on the target, and further strengthen the gas pressure barrier effect. If the CO concentration continues to rise and approaches the critical warning value, the system will issue an alarm and can increase the nitrogen injection flow according to the preset scheme or notify personnel to intervene.

[0073] In summary, the present application builds a set of comprehensive fire prevention and extinguishing system with complete system, rapid response and accurate regulation and control through the organic connection and synergistic effect of the four steps, effectively solves the problem of mine fire prevention and control under complex conditions such as shallow depth.

[0074] The above shows and describes the basic principles, main features and advantages of the present application. It should be understood by those skilled in the art that the present application is not limited by the above examples, and the above examples and descriptions in the specification are only preferred examples of the present application and do not limit the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the present application. The scope of protection of the present application is defined by the appended claims and their equivalents.​​

Claims

1. A method for preventing and extinguishing fires in mines by parallel pressurization, characterized in that, Includes the following steps: Step S1: Install a pressure regulating fan in the intake airway of the coal mining face and install an automatically adjustable air window in the return airway to form a fan-air window combined pressure regulating system; Simultaneously, the intake and return air corners of the aforementioned coal mining face were sealed, and the surface fissures above the goaf were also sealed. Step S2: Real-time acquisition of absolute pressure, temperature, humidity and elevation parameters at two locations: near the surface fissure and at the entrance of the underground return airway. Then, based on the above parameters, the target pressure increase value is dynamically calculated online. Subsequently, the aforementioned fan-window combined pressure regulating system is controlled to adjust the opening and closing area of ​​the window in order to form a stable equivalent pressure boosting field in the coal mining face area; Step S3: After the equivalent pressure field is established stably, nitrogen is injected into the goaf. Driven by the aerodynamic force generated by the equivalent pressure field, the nitrogen diffuses into the depth of the goaf, the connected old roadways and the surface fissures to inert the fire zone. Step S4: Monitor the CO concentration in real time at key locations in the return air corner and / or return airway; The target pressure rise value calculated in step S2 is used as the basic control benchmark, and the monitored CO concentration is used as the linkage control constraint. When the CO concentration is abnormal, the operating parameters of the fan-window joint pressure regulation system are automatically fine-tuned. In step S2, the pressure difference between the two monitoring points on the surface and downhole is calculated, and temperature, humidity and elevation parameters are introduced for compensation, so as to determine the pressure value required to make the pressure difference between the surface and downhole monitoring points approach zero as the target pressure increase value. The formula for calculating the target boost value is as follows: ； In the formula, For the target boost pressure value, This represents the absolute atmospheric pressure at the surface fissure. This refers to the absolute atmospheric pressure at the outer entrance of the underground return airway. It is the acceleration due to gravity. Let be the specific gas constant of dry air. This refers to the absolute pressure at the surface fissure. The absolute pressure at the entrance of the underground return airway. This is the elevation at the surface fissure. This is the elevation of the outer entrance of the underground return airway. Temperature at the surface fissure. The temperature at the outside of the underground return airway. The specific humidity at the surface fissures. The humidity level is measured at the outer entrance of the underground return airway.

2. The mine parallel pressurization fire prevention and extinguishing method according to claim 1, characterized in that: In step S1, two pressure regulating fans are installed in parallel in the air intake roadway, and it is ensured that the air outlet direction of the fans is consistent with the airflow direction of the roadway.

3. The mine parallel pressurization fire prevention and extinguishing method according to claim 1, characterized in that: In step S1, the automatically adjustable window is a louvered window controlled by an electric push rod.

4. The mine parallel pressurization fire prevention and extinguishing method according to claim 1, characterized in that: In step S1, a barrier wall is constructed using polymer materials or sandbags to seal the air inlet corner and the air return corner.

5. The mine parallel pressurization fire prevention and extinguishing method according to claim 1, characterized in that: In step S2, multi-parameter sensors for monitoring absolute pressure, temperature, and humidity are installed near surface fissures and at the entrance of underground return airway.

6. The mine parallel pressurization fire prevention and extinguishing method according to claim 1, characterized in that: In step S4, sensors for monitoring CO concentration are installed in the return air corner and return air alley.

7. The mine parallel pressurization fire prevention and extinguishing method according to claim 1, characterized in that: In step S4, a preset CO concentration warning threshold is established. When the monitored CO concentration exceeds the above-mentioned warning threshold, the linkage control will increase the pressure increment based on the target pressure increase value; The pressure increase is 10-30 Pa.

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