Quantitative calculation method for air leakage

Abstract

The invention provides an air leakage quantitative calculation method. The air leakage quantitative calculation method comprises the following steps: determining an air leakage calculation formula according to an air leakage scene; if air leakage occurs on the earth surface, the tracer gas is released into the to-be-measured laneway firstly, and the release amount of the tracer gas is q; then the earth surface air leakage rate QD is determined according to the formula QD = Qc + QJ-QM-QP-QW-QN; qc is the total gas extraction flow of the goaf of the working face, QJ is the difference between the air inlet volume and the air return volume of the working face, QM is the air leakage amount from the peripheral working face or the goaf to the working face, QP is the air leakage amount from the peripheral roadway to the working face, QW is the absolute gas and carbon dioxide emission amount of the working face, and QN is the fireproof nitrogen injection flow of the working face to the goaf; if air leakage occurs underground, the closed air leakage quantity QDFQ is determined according to the formula # imgabs0 #; kDFQ is the air leakage coefficient of the wind-shield wall, delta h is the pressure difference between the two sides of the wind-shield wall, b is the thickness of the wind-shield wall, and mu is the perimeter of the contact surface between the wind-shield wall and the roadway wall. The problem that in the prior art, the earth surface air leakage amount and the underground airtight air leakage amount cannot be measured and calculated is solved.

Description

Technical Field

[0001] The invention relates to the technical field of coal mine production safety, and in particular to a method for quantitatively calculating air leakage. Background Art

[0002] At present, spontaneous combustion of coal mines is one of the main disasters in the coal mine production process. The occurrence and expansion of coal mine fires are related to air leakage and oxygen supply. If the air leakage is lower than the first set value, the oxygen supply conditions required for oxidation and spontaneous combustion cannot be supplied, and the coal body will be extinguished due to lack of oxygen and will not spontaneously combust; if the air leakage is greater than the second set value, the air leakage will take away a large amount of heat generated by coal oxidation, so that the heat generated by coal oxidation is lower than the heat dissipation caused by leakage. The coal body cannot store heat and heat up, so it will not spontaneously combust. That is, the air leakage at this time will destroy the heat storage environment required for coal spontaneous combustion; when the air leakage is between the above two values, the coal body has both sufficient oxygen supply conditions and a good heat storage environment, reaching the natural ignition period of the coal body, and there is a possibility of spontaneous combustion.

[0003] In the prior art, air leakage that can cause spontaneous combustion of coal mainly includes the following:

[0004] ① After the mine is mined, the mining fracture zone is connected to the surface and causes surface air leakage;

[0005] ② The sealed goaf in the mine is ruptured due to pressure, and the fresh air flow from the mine leaks into the sealed goaf, resulting in air leakage;

[0006] ③ During the mining process of the fully mechanized caving face in the mine, fresh air from the working face flows through the goaf, causing air leakage;

[0007] ④ The coal pillars in the underground tunnels are compressed and broken, and the depth of the broken coal pillars is large, resulting in air leakage in the tunnels;

[0008] ⑤ Air leakage caused by the rupture of the coal pillars isolating the goaf.

[0009] For air leakage of types ③ to ⑤, the MTT 845-1999 SF for coal mine tunnels can be used. 6 The corresponding measurement is carried out in accordance with the Technical Specifications for Tracer Gas Leakage Detection, but there is currently no clear measurement method for Class ① and Class ② leakage. Summary of the invention

[0010] The main purpose of the present invention is to provide a quantitative calculation method for air leakage, so as to solve the problem that the surface air leakage and the underground air leakage cannot be measured in the prior art.

[0011] In order to achieve the above-mentioned object, the present invention provides a quantitative calculation method for air leakage, comprising: determining a calculation formula for air leakage according to the scene where air leakage occurs; if air leakage occurs on the surface, first releasing tracer gas into the well to be measured, and the release amount of tracer gas is q; then according to the formula: QD =Q c +Q J -Q M -Q P -Q W -Q N Determine the surface air leakage Q D ;Q c is the total gas extraction flow rate of the goaf of the working face, Q J Q is the difference between the inlet and return air volume of the working face, M Q is the air leakage from the surrounding working face or goaf to the working face, P is the air leakage from the surrounding tunnels to the working face, Q W is the absolute outflow of gas and carbon dioxide at the working face, Q N The nitrogen injection flow rate for fire prevention from the working face to the goaf; if air leakage occurs underground, according to the formula: Determine the air leakage volume Q DFQ ; K DFQ is the air leakage coefficient of the windbreak wall, Δh is the pressure difference on both sides of the windbreak wall, b is the thickness of the windbreak wall, and μ is the circumference of the contact surface between the windbreak wall and the tunnel wall.

[0012] Furthermore, the method for determining the release amount q of the tracer gas includes: determining the release amount q according to the formula: q=KCQ; wherein K is a coefficient and takes a value of 4 to 5, C is the minimum concentration of the tracer gas in the predetermined airflow, and Q is the air volume passing through the measured well tunnel.

[0013] Furthermore, the method of releasing the tracer gas into the well to be tested includes: according to the formula Determine the distance L between the release point of the tracer gas and the sampling point; where S is the cross-sectional area of ​​the well and U is the perimeter length of the well.

[0014] Furthermore, the air leakage from the surrounding tunnels to the working face Q P The determination method includes: according to the formula: It is concluded that: i is the concentration of the tracer gas in the i-th section of the well to be tested, C i+1 is the concentration of the tracer gas in the i+1th section of the well to be tested.

[0015] Furthermore, the air leakage from the surrounding working face or goaf to the working face Q M The determination method comprises: step S1: determining the pressure energy balance area of ​​the working surface; step S2: according to the formula: Determine the air leakage Q from the surrounding working face or goaf to the working face M Among them, C i 'For S i The concentration of the tracer gas measured at the point, C h1 For Sh The concentration of the tracer gas measured for the first time at point h2 For S i The point R is used as the release point of the tracer gas. 2 , the release amount of tracer gas is q, and at S h Sampling is performed at the point to determine the concentration of tracer gas.

[0016] Furthermore, the method for determining the pressure energy balance area of ​​the working face includes: selecting a zone in the air intake tunnel of the working face that is greater than or equal to L from the coal wall. S The point where the airflow is stable is used as the release point of the tracer gas R 1 , set the sampling and detection point S of tracer gas at the same distance from the coal wall in the return air lane h , set the sampling and detection point S of tracer gas at the same distance from the coal wall in the working face i ; in R 1 The tracer gas is released continuously and stably at the point S h The concentration of tracer gas is C h1 ; Then use the tracer gas detector to detect the gas flow along the working surface from S 1 The concentration of the tracer gas is measured point by point. When S i At this point, the concentration of the tracer gas will remain constant and be C i ', S i The position after the point is the pressure energy balance area of ​​the working surface.

[0017] Furthermore, the difference in the air volume between the working face and the return air volume Q J The determination method includes: selecting a stable airflow point with a distance greater than or equal to (L+10m) from the coal wall as the release point R of the tracer gas 1 , set the tracer gas detection point S at the position 10m away from the coal wall in the air intake tunnel and at the stable air flow position (L+10m) away from the coal wall in the return air tunnel. 1 , S 2 , and release the tracer gas continuously and stably at the release point with a release amount of q; according to the formula: Determine the difference Q between the inlet and return air volume of the working face J Among them, C 1 is the detection point S 1 The concentration of tracer gas at 2 is the detection point S 2 The concentration of tracer gas at the

[0018] Furthermore, the tracer gas is SF 6 .

[0019] Furthermore, the air leakage coefficient K of the windbreak wall is DFQ Determined by the construction material of the windbreak wall.

[0020] Furthermore, the method of releasing the tracer gas into the well to be tested includes: releasing the tracer gas through a gas release device, the gas release device includes a high-pressure gas storage cylinder, and a control valve is arranged at the outlet of the high-pressure gas storage cylinder.

[0021] By applying the technical solution of the present invention, the calculation formula of the air leakage amount is first determined according to the scene where the air leakage occurs; if air leakage occurs on the surface, the tracer gas is first released into the well to be measured, and the release amount of the tracer gas is q; then according to the formula: Q D =Q c +Q J -Q M -Q P -Q W -Q N Determine the surface air leakage Q D ;Q c is the total gas extraction flow rate of the goaf of the working face, Q J Q is the difference between the inlet and return air volume of the working face, M Q is the air leakage from the surrounding working face or goaf to the working face, P is the air leakage from the surrounding tunnels to the working face, Q W is the absolute outflow of gas and carbon dioxide at the working face, Q N The nitrogen injection flow rate for fire prevention from the working face to the goaf; if air leakage occurs underground, according to the formula: Determine the air leakage volume Q DFQ ; K DFQ is the air leakage coefficient of the windbreak wall, Δh is the pressure difference on both sides of the windbreak wall, b is the thickness of the windbreak wall, and μ is the circumference of the contact surface between the windbreak wall and the tunnel wall. In this way, the quantitative calculation method of air leakage in this application can measure the surface air leakage and the underground airtight air leakage, so as to accurately evaluate the impact of surface air leakage on the ventilation system of coal mines, especially in mining areas, which helps to timely discover and repair air leakage points and ensure the safe operation of mines, thereby solving the problem that the surface air leakage and the underground airtight air leakage cannot be measured in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0023] Figure 1 A flow chart of an embodiment of a method for quantitatively calculating air leakage according to the present invention is shown. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0026] In the present invention, unless otherwise specified, the directional words used, such as "up" and "down", usually refer to the directions shown in the drawings, or to the vertical, perpendicular or gravity directions; similarly, for ease of understanding and description, "left" and "right" usually refer to the left and right shown in the drawings; "inside" and "outside" refer to the inside and outside relative to the outline of each component itself, but the above directional words are not used to limit the present invention.

[0027] In order to solve the problem in the prior art that surface air leakage and underground air leakage cannot be measured, the present application provides a method for quantitatively calculating air leakage.

[0028] like Figure 1 As shown in the figure, the quantitative calculation method of air leakage includes:

[0029] Determine the calculation formula for air leakage based on the scenario where air leakage occurs;

[0030] If air leakage occurs on the surface, first release tracer gas into the well to be tested, and the release amount of tracer gas is q; then according to the formula:

[0031] Q D =Q c +Q J -Q M -Q P -Q W -Q N Determine the surface air leakage Q D ;Q c is the total gas extraction flow rate of the goaf of the working face, Q J Q is the difference between the inlet and return air volume of the working face, M Q is the air leakage from the surrounding working face or goaf to the working face, P is the air leakage from the surrounding tunnels to the working face, Q W is the absolute outflow of gas and carbon dioxide at the working face, Q N The nitrogen injection flow rate for fire prevention of the working surface towards the goaf;

[0032] If air leakage occurs underground, according to the formula: Determine the air leakage volume Q DFQ ; K DFQis the air leakage coefficient of the windbreak wall, Δh is the pressure difference on both sides of the windbreak wall, b is the thickness of the windbreak wall, and μ is the circumference of the contact surface between the windbreak wall and the tunnel wall.

[0033] By applying the technical solution of this embodiment, the quantitative calculation method of air leakage in this embodiment can measure the surface air leakage and the underground enclosed air leakage, so as to accurately evaluate the impact of surface air leakage on the coal mine ventilation system, especially in the mining area, which helps to timely discover and repair air leakage points and ensure the safe operation of the mine, thereby solving the problem that the surface air leakage and the underground enclosed air leakage cannot be measured in the prior art.

[0034] In this embodiment, the method for determining the release amount q of the tracer gas includes:

[0035] The release amount q is determined according to the formula: q=KCQ; wherein K is a coefficient and takes a value of 4 to 5, C is the minimum concentration of the tracer gas in the predetermined air flow, and Q is the air volume passing through the measured well tunnel.

[0036] Specifically, K is 4, C is 8-10, and the measured tunnel air volume Q is 600m 3 / min. The above method ensures that the concentration of the tracer gas is within the detection range and is applicable to tunnels with different air volumes and wind speeds, which improves the accuracy and applicability of the detection. In practical applications, this method can not only quickly adapt to the detection needs under various wind speed conditions, but also ensure the uniform distribution of the tracer gas concentration, avoiding the influence of local excessive or low concentration on the detection results. Especially in an environment with unstable wind speed, the stability advantage of this method is more obvious, providing reliable technical support for ventilation detection in coal mines.

[0037] In this embodiment, the method of releasing the tracer gas into the well to be tested includes:

[0038] According to the formula Determine the distance L between the release point of the tracer gas and the sampling point; where S is the cross-sectional area of ​​the well and U is the perimeter length of the well.

[0039] Specifically, by scientifically calculating the distance between the release point and the sampling point, the local concentration of the tracer gas in the initial stage of release can be effectively avoided to be too high or too low, thus ensuring the reliability of the detection data. The application of this method can ensure that the changes in the tracer gas concentration can be accurately recorded and analyzed during the gas release and sampling process, avoiding detection errors caused by too high or too low concentration. In a complex environment where multiple tunnels intersect, this method can more accurately locate and calculate the air leakage, which helps to optimize the layout of the ventilation network, reduce energy waste, and improve the economic benefits of coal mines.

[0040] In this embodiment, the air leakage from the surrounding tunnel to the working face is Q P The determination methods include:

[0041] According to the formula: It is concluded that: i is the concentration of the tracer gas in the i-th section of the well to be tested, C i+1 is the concentration of the tracer gas in the i+1th section of the well to be tested.

[0042] Specifically, the above method can accurately calculate the air leakage between each tunnel, providing a scientific basis for optimizing the ventilation path and improving ventilation efficiency.

[0043] In this embodiment, the air leakage from the surrounding working face or the goaf to the working face Q M The determination methods include:

[0044] Step S1: determining the pressure energy balance area of ​​the working surface;

[0045] Step S2: According to the formula: Determine the air leakage Q from the surrounding working face or goaf to the working face M ;

[0046] Among them, C i 'For S i The concentration of the tracer gas measured at the point, C h1 For S h The concentration of the tracer gas measured for the first time at point h2 For S i The point R is used as the release point of the tracer gas. 2 , the release amount of tracer gas is q, and at S h Sampling is performed at the point to determine the concentration of tracer gas.

[0047] Specifically, by accurately measuring the changes in gas concentration in the pressure-energy balance area, the air leakage between the goaf and the working face can be effectively evaluated. In the coal mining process, this method can help enterprises promptly discover the air leakage points between the goaf and the working face, and adjust the ventilation strategy and take sealing measures.

[0048] In this embodiment, the method for determining the pressure energy balance area of ​​the working surface includes:

[0049] In the air inlet tunnel of the working face, select a distance greater than or equal to L from the coal wall. S The point where the airflow is stable is used as the release point of the tracer gas R 1 , set the sampling and detection point S of tracer gas at the same distance from the coal wall in the return air lane h , set the sampling and detection point S of tracer gas at the same distance from the coal wall in the working face i ; in R 1 The tracer gas is released continuously and stably at the point S hThe concentration of tracer gas is C h1 ; Then use the tracer gas detector to detect the gas flow along the working surface from S 1 The concentration of the tracer gas is measured point by point. When S i At this point, the concentration of the tracer gas will remain constant and be C i ', S i The position after the point is the pressure energy balance area of ​​the working surface.

[0050] Specifically, the above method can accurately identify the pressure-energy balance area, provide key data for subsequent air leakage calculations, and is applicable to various complex working face environments. The application of this method can not only improve the accuracy of coal mine ventilation system detection, but also help companies better understand the ventilation characteristics of the working face, and provide scientific guidance for improving ventilation conditions and improving the working environment of miners. Especially in the coal mining process, accurate identification of the pressure-energy balance area plays an important role in preventing gas accumulation and controlling dust concentration, and helps create safer and healthier working conditions.

[0051] In this embodiment, the difference between the inlet and return air volume of the working face Q J The determination methods include:

[0052] Select a stable airflow point with a distance greater than or equal to (L+10m) from the coal wall as the release point R of the tracer gas. 1 , set the tracer gas detection point S at the position 10m away from the coal wall in the air intake tunnel and at the stable air flow position (L+10m) away from the coal wall in the return air tunnel. 1 , S 2 , and release the tracer gas continuously and stably at the release point with a release amount of q;

[0053] According to the formula: Determine the difference Q between the inlet and return air volume of the working face J Among them, C 1 is the detection point S 1 The concentration of tracer gas at 2 is the detection point S 2 The concentration of tracer gas at the

[0054] Specifically, the above method can accurately measure the difference in the amount of incoming and outgoing air, which plays an important role in adjusting the ventilation system and ensuring the air quality of the working face. In practical applications, this method helps to promptly detect imbalance problems in the ventilation system, and ensure the air quality of the working face by adjusting the operating parameters of the ventilation equipment or optimizing the layout of the ventilation network, reducing the concentration of dust and harmful gases, and providing miners with a healthier and safer working environment. Especially in working faces with high dust and gas concentrations, the application effect of this method is more significant, which can effectively reduce the occurrence of occupational diseases and safety accidents and improve the safety production level of coal mines.

[0055] In this embodiment, the tracer gas is SF 6 .

[0056] Specifically, SF 6 Gas has stable chemical properties, is not easy to react with other substances, and has extremely low content in the atmosphere. Therefore, it has high accuracy and reliability as a tracer gas. It is suitable for air leakage detection in coal mine ventilation systems and can effectively avoid the potential safety hazards caused by the use of other gases. 6 As a tracer gas, it not only ensures the accuracy of the test results, but also avoids the risk of gas explosion caused by the use of other gases in high-gas mines.

[0057] In this embodiment, the air leakage coefficient K of the windbreak wall is DFQ Determined by the construction material of the windbreak wall.

[0058] Specifically, the material of the windbreak wall directly affects its air leakage coefficient K DFQ , personalized evaluation of windbreaks of different materials is carried out, providing a scientific basis for the design and maintenance of windbreaks, and is suitable for the detection and optimization of various underground ventilation facilities. In practical applications, the above method can help enterprises reasonably select the material and structure of windbreaks, reduce ventilation resistance, and improve ventilation efficiency, which plays an important role in optimizing the ventilation network of coal mines and reducing ventilation costs.

[0059] In this embodiment, the method of releasing the tracer gas into the well to be tested includes:

[0060] The tracer gas is released through a gas release device, which includes a high-pressure gas storage cylinder, and a control valve is arranged at the outlet of the high-pressure gas storage cylinder.

[0061] Specifically, the gas release device is easy to operate and has strong controllability, which is suitable for rapid detection at coal mine sites and improves work efficiency. The gas release device using a high-pressure gas storage bottle and a control valve can not only ensure the accurate release of the tracer gas, but also adjust the release amount and release time as needed, which is suitable for flexible detection needs at coal mine sites. In practical applications, this method can significantly shorten the detection cycle and improve detection efficiency, which is of great value to the daily management and maintenance of coal mines.

[0062] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0063] First, determine the calculation formula for the amount of air leakage according to the scene where air leakage occurs; if air leakage occurs on the surface, first release tracer gas into the well to be measured, and the amount of tracer gas released is q; then according to the formula: Q D =Q c +QJ -Q M -Q P -Q W -Q N Determine the surface air leakage Q D ;Q c is the total gas extraction flow rate of the goaf of the working face, Q J Q is the difference between the inlet and return air volume of the working face, M Q is the air leakage from the surrounding working face or goaf to the working face, P is the air leakage from the surrounding tunnels to the working face, Q W is the absolute outflow of gas and carbon dioxide at the working face, Q N The nitrogen injection flow rate for fire prevention from the working face to the goaf; if air leakage occurs underground, according to the formula: Determine the air leakage volume Q DFQ ; K DFQ is the air leakage coefficient of the windbreak wall, Δh is the pressure difference on both sides of the windbreak wall, b is the thickness of the windbreak wall, and μ is the circumference of the contact surface between the windbreak wall and the tunnel wall. In this way, the quantitative calculation method of air leakage in this application can measure the surface air leakage and the underground airtight air leakage, so as to accurately evaluate the impact of surface air leakage on the ventilation system of coal mines, especially in mining areas, which helps to timely discover and repair air leakage points and ensure the safe operation of mines, thereby solving the problem that the surface air leakage and the underground airtight air leakage cannot be measured in the prior art.

[0064] Obviously, the above-described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0065] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0066] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0067] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A quantitative calculation method for air leakage, characterized in that: include: Determine the calculation formula for air leakage based on the scenario where air leakage occurs; If air leakage occurs on the ground, first release tracer gas into the well to be tested, and the release amount of the tracer gas is q; then according to the formula: Q D =Q c +Q J -Q M -Q P -Q W -Q N Determine the surface air leakage Q D ;Q c is the total gas extraction flow rate of the goaf of the working face, Q J Q is the difference between the inlet and return air volume of the working face, M Q is the air leakage from the surrounding working face or goaf to the working face, P is the air leakage from the surrounding tunnels to the working face, Q W is the absolute outflow of gas and carbon dioxide at the working face, Q N The nitrogen injection flow rate for fire prevention of the working surface towards the goaf; If air leakage occurs underground, according to the formula: Determine the air leakage volume Q DFQ ; K DFQ is the air leakage coefficient of the windbreak wall, Δh is the pressure difference on both sides of the windbreak wall, b is the thickness of the windbreak wall, and μ is the circumference of the contact surface between the windbreak wall and the tunnel wall.

2. The method for quantitatively calculating air leakage according to claim 1, characterized in that: The method for determining the release amount q of the tracer gas comprises: Determine the release amount q according to the formula: q=KCQ; Among them, K is a coefficient and its value is 4 to 5, C is the minimum concentration of tracer gas in the predetermined wind flow, and Q is the air volume passing through the measured well tunnel.

3. The method for quantitatively calculating air leakage according to claim 1, characterized in that: Methods for releasing tracer gas into the well to be tested include: According to the formula Determine the distance L between the release point of the tracer gas and the sampling point; Among them, S is the cross-sectional area of ​​the shaft and U is the perimeter length of the shaft.

4. The method for quantitatively calculating air leakage according to claim 1, characterized in that: Air leakage from surrounding tunnels to the working face Q P The determination methods include: According to the formula: It turns out that: Among them, C i is the concentration of the tracer gas in the i-th section of the well to be tested, C i+1 is the concentration of the tracer gas in the i+1th section of the well to be tested.

5. The method for quantitatively calculating air leakage according to claim 1, characterized in that: Air leakage from surrounding working faces or goaf to working faces Q M The determination methods include: Step S1: determining the pressure energy balance area of ​​the working surface; Step S2: According to the formula: Determine the air leakage Q from the surrounding working face or goaf to the working face M ; Among them, C i 'For S i The concentration of the tracer gas measured at the point, C h1 For S h The concentration of the tracer gas measured for the first time at point h2 For S i The point R2 is taken as the release point of the tracer gas, the release amount of the tracer gas is q, and at S h Sampling is performed at the point to determine the concentration of tracer gas.

6. The method for quantitatively calculating air leakage according to claim 1, characterized in that: Methods for determining the pressure energy balance area of ​​the working surface include: In the air inlet tunnel of the working face, select a distance greater than or equal to L from the coal wall. S The stable airflow point is taken as the release point R1 of the tracer gas, and the sampling and detection point S of the tracer gas is set at the same distance from the coal wall in the return air lane. h , set the sampling and detection point S of tracer gas at the same distance from the coal wall in the working face i ; The tracer gas is continuously and stably released at point R1 with a release amount of q. h The concentration of tracer gas is C h1 ; Then use the tracer gas detector to measure the concentration of the tracer gas point by point along the working surface starting from point S1. i At this point, the concentration of the tracer gas will remain constant and be C i ', S i The position after the point is the pressure energy balance area of ​​the working surface.

7. The method for quantitatively calculating air leakage according to claim 1, characterized in that: Difference of air volume inlet and return at working surface Q J The determination methods include: Select a stable airflow point with a distance greater than or equal to (L+10m) from the coal wall as the release point R1 of the tracer gas, set the detection points S1 and S2 of the tracer gas at a distance of 10m from the coal wall in the air intake tunnel and at a stable airflow point (L+10m) from the coal wall in the return air tunnel, and release the tracer gas continuously and stably at the release point with a release amount of q; According to the formula: Determine the difference Q between the inlet and return air volume of the working face J ; Wherein, C1 is the concentration of the tracer gas at the detection point S1, and C2 is the concentration of the tracer gas at the detection point S2.

8. The method for quantitatively calculating air leakage according to claim 1, characterized in that: The tracer gas is SF6.

9. The method for quantitatively calculating air leakage according to claim 1, characterized in that: Air leakage coefficient K of windbreak wall DFQ Determined by the construction material of the windbreak wall.

10. The method for quantitatively calculating air leakage according to claim 1, characterized in that: Methods for releasing tracer gas into the well to be tested include: The tracer gas is released through a gas release device, which includes a high-pressure gas storage bottle, and a control valve is arranged at the outlet of the high-pressure gas storage bottle.

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