Blocking method for underground vertical shaft of coal mine

Abstract

The invention provides a coal mine underground vertical shaft blocking method which comprises the steps that a blocking mode is selected according to reuse attributes of an underground vertical shaft, and the blocking mode comprises permanent blocking and temporary blocking; if the plugging is permanent plugging, a continuous and irreversible sealing structure is constructed in the hidden vertical shaft to block an air flow channel of the hidden vertical shaft, and if the plugging is temporary plugging, a reversible sealing structure is constructed in the hidden vertical shaft, and an environment monitoring interface is arranged to monitor gas in the hidden vertical shaft. The problem of blocking of abandoned or stopped underground vertical shafts in a coal mine is effectively solved, and the risk that a local ventilation system of the mine is disordered due to air leakage is eliminated for a permanent stopping scene; and for a temporary shutdown scene, real-time monitoring of gas in the well is achieved while sealing reliability is guaranteed, the safety requirements for air leakage prevention and spontaneous combustion prevention in the temporary shutdown period are met, convenient breaking conditions are provided for follow-up reuse, and the hidden danger of ventilation system unbalance and spontaneous combustion caused by mixed use of modes in a traditional plugging technology is eradicated fundamentally.

Description

Technical Field

[0001] This invention relates to the technical field of sealing underground vertical shafts in coal mines, and specifically to a method for sealing underground vertical shafts in coal mines. Background Technology

[0002] In coal mine safety production practices, underground shafts, as key roadway facilities, are directly affected by the sealing operations after their decommissioning, impacting the stability of the mine's ventilation system and fire prevention and extinguishing safety. Currently, the industry commonly suffers from inadequate sealing processes when dealing with abandoned or temporarily decommissioned underground shafts. This leads to abnormal airflow through weak points in the seal, severely disrupting the balance of the local ventilation system. More seriously, such air leakage provides a continuous oxygen supply to the residual coal within the shaft, inducing coal-oxygen interaction and potentially triggering spontaneous combustion accidents.

[0003] Specifically, existing sealing methods suffer from three major drawbacks. First, the sealing schemes lack targeted design based on the intended use of the tunnel. Whether permanently abandoned or temporarily shut down, the same masonry sealing method is used, failing to consider the differentiated requirements for sealing reliability and ease of removal under different scenarios. This crude approach leads to the permanent sealing structure being prone to developing through-cracks, creating air leakage channels, while temporary sealing bodies are difficult to safely remove during reuse due to structural hardening. Therefore, existing technologies lack a systematic solution to these shortcomings in underground shaft sealing.

[0004] Therefore, existing technologies still need further development. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned technical deficiencies and provide a method for sealing underground vertical shafts in coal mines, so as to solve the problems existing in the prior art.

[0006] To achieve the above-mentioned technical objectives, according to a first aspect of the present invention, the present invention provides a method for sealing a coal mine underground shaft, comprising: The sealing method is selected based on the reuse properties of the underground vertical shaft, and the sealing method includes permanent sealing and temporary sealing; If it is to be a permanent seal, a continuous and irreversible sealing structure is constructed inside the concealed shaft to block the airflow passage of the concealed shaft; If it is a temporary sealing, a reversible sealing structure is constructed inside the underground shaft, and an environmental monitoring interface is installed to monitor the gas inside the underground shaft.

[0007] Specifically, the selection of the sealing method based on the reuse attributes of the underground shaft includes: If the reuse attribute of the underground shaft is permanent disuse or abandonment, then the sealing method adopted is permanent sealing. If the reuse attribute of the underground shaft is temporarily suspended, then the sealing method adopted is temporary sealing.

[0008] Specifically, if the sealing is permanent, a continuous and irreversible sealing structure is constructed within the concealed shaft to block the airflow passage of the shaft, including: A protective steel plate is installed at the bottom of the concealed vertical shaft. A pressure-bearing sealing layer, an intermediate isolation layer, and an end-face sealing layer are sequentially installed above the protective steel plate to block the airflow channel of the concealed vertical shaft.

[0009] Specifically, the method for setting the pressure-bearing sealing layer includes: injecting concrete over the protective steel plate to fill it; The method for setting an intermediate isolation layer includes: filling a solidified material over the concrete up to the top of the underground shaft; The method for setting the end face sealing layer includes: laying I-beams at the top of the dark vertical shaft and covering it with a cement layer for sealing.

[0010] Specifically, the thickness of the concrete poured above the protective steel plate is determined based on the depth of the shaft, including: When the depth of the underground shaft is less than the first preset depth, the thickness of the injected concrete is greater than or equal to the product of the first preset depth and the first preset ratio. When the depth of the underground shaft is greater than or equal to the first preset depth, the thickness of the injected concrete is greater than or equal to the second preset depth.

[0011] Specifically, if the sealing is temporary, a reversible sealing structure is constructed within the underground shaft, including: A protective steel plate is installed at the bottom of the underground shaft, and an elastic sealing layer and an end face sealing layer are sequentially installed above the protective steel plate.

[0012] Specifically, the method for setting the elastic pressure layer includes: injecting silica gel above the protective steel plate, wherein the thickness of the injected silica gel is determined according to the depth of the dark vertical well; The method for setting the end face sealing layer includes: laying I-beams at the top of the dark vertical shaft and covering it with a cement layer for sealing.

[0013] Specifically, the thickness of the injected silica gel is determined according to the depth of the dark vertical well, including: When the depth of the dark well is less than the first preset depth, the thickness of the injected silica gel is greater than or equal to the product of the first preset depth and the first preset ratio; When the depth of the dark well is greater than or equal to the first preset depth, the thickness of the injected silica gel is greater than or equal to the second preset depth.

[0014] Specifically, the method for controlling the thickness of the injected silica gel layer includes: An intrinsically safe ultrasonic depth sensor for mining is used to monitor the filling height of silica gel in real time. The intrinsically safe ultrasonic depth sensor is vertically installed on the side wall of the dark shaft, and the monitoring data is transmitted to the control terminal above ground in real time. When the thickness of the injected silica gel reaches the required thickness, the command to stop the injection of silica gel is automatically triggered.

[0015] Specifically, the setting of an environmental monitoring interface to monitor the gas inside the dark vertical shaft includes: A gas monitoring bundle extending into the interior of the underground shaft is laid at the bottom of the shaft. The opening of the gas monitoring bundle is sealed, and the gas inside the gas monitoring bundle is periodically collected and its composition is analyzed to monitor the gas inside the underground shaft.

[0016] Beneficial effects: This invention provides a method for sealing underground vertical shafts in coal mines. By selecting sealing modes based on the different reuse attributes of underground vertical shafts, it effectively solves the problem of sealing abandoned or decommissioned underground vertical shafts in coal mines. For permanent decommissioning scenarios, a continuous and irreversible sealing structure is constructed to completely block the airflow channel, eliminating the risk of local ventilation system disorder caused by air leakage. For temporary decommissioning scenarios, a reversible sealing structure is adopted and an environmental monitoring interface is set up to achieve real-time monitoring of gas in the shaft while ensuring the reliability of the seal. This not only meets the safety requirements of preventing air leakage and spontaneous combustion during temporary decommissioning, but also provides convenient removal conditions for subsequent reuse. It fundamentally eliminates the ventilation system imbalance and spontaneous combustion hazards caused by the mixed use of modes in traditional sealing processes. Attached Figure Description

[0017] Figure 1 This is a flowchart of the coal mine underground shaft sealing method provided in a specific embodiment of the present invention; Figure 2 This is a cross-sectional view of the permanent sealing of the underground vertical well provided in a specific embodiment of the present invention; Figure 3 This is a cross-sectional view of the temporary sealing of the underground vertical shaft provided in a specific embodiment of the present invention; The reference numerals in the above figures are as follows: 1. Concealed vertical shaft; 2. Protective steel plate; 3. Concrete; 4. Curing material; 5. I-beam; 6. Silicate gel. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Based on the embodiments in this application, other similar embodiments obtained by those skilled in the art without creative effort should all fall within the scope of protection of this application. Furthermore, directional terms mentioned in the following embodiments, such as "up," "down," "left," and "right," are only for reference to the directions in the accompanying drawings; therefore, the directional terms used are for illustrative purposes and not for limiting the invention.

[0019] The present invention will be further described below with reference to the accompanying drawings and preferred embodiments.

[0020] Please see Figure 1 This embodiment provides a method for sealing a coal mine underground shaft, including: The sealing method is selected based on the reuse attributes of the underground shaft 1. The sealing methods include permanent sealing and temporary sealing. For permanent sealing, a continuous and irreversible sealing structure is constructed within the underground shaft 1 to block the airflow channel. For temporary sealing, a reversible sealing structure is constructed within the underground shaft 1, and an environmental monitoring interface is installed to monitor the gas inside the shaft 1. This effectively solves the sealing problem of abandoned or decommissioned underground shafts 1 in coal mines. The strategy of selecting sealing methods based on different reuse attributes has brought significant technical benefits. From a safety perspective, the continuous and irreversible sealing structure formed by permanent sealing fundamentally eliminates airflow channels, effectively preventing harmful gases from accumulating in abandoned underground shafts 1 and spreading to other work areas, greatly protecting the lives of underground coal mine workers. The environmental monitoring interface installed in temporary sealing allows for real-time monitoring of the gas conditions inside the underground shaft 1. Any abnormal data can trigger timely warnings, facilitating appropriate measures by staff to eliminate safety hazards in advance, further improving the safety of coal mine production. Meanwhile, temporary sealing is adopted for the underground shaft 1 that has the potential for reuse, avoiding unnecessary permanent construction investment. Moreover, the reversible sealing structure makes the reuse process more convenient, reducing the time and cost of reopening the underground shaft 1, and providing an efficient and safe underground shaft sealing solution for the entire coal mining industry.

[0021] Specifically, in this embodiment, the sealing method is selected based on the reuse attribute of the concealed vertical shaft 1. Specifically, if the reuse attribute of the concealed vertical shaft 1 is permanent disuse or abandonment, then permanent sealing is used; if the reuse attribute of the concealed vertical shaft 1 is temporary disuse, then temporary sealing is used. By precisely matching the sealing method with the usage status of the concealed vertical shaft 1, an irreversible and complete seal is implemented for permanently disused shafts, eliminating the risk of ventilation disturbances caused by air leakage. For temporarily disused shafts, a reversible seal combined with real-time monitoring is used, preserving convenient removal conditions for reuse while ensuring safety, thus preventing spontaneous combustion hazards and system imbalances from the source.

[0022] See Figure 2 In this embodiment, if it is a permanent seal, a continuous and irreversible sealing structure is constructed within the concealed vertical shaft 1 to block the airflow passage of the concealed vertical shaft 1, including: A protective steel plate 2 is installed at the lower opening of the concealed vertical shaft 1. A pressure-bearing sealing layer, an intermediate isolation layer, and an end-face sealing layer are sequentially installed above the protective steel plate 2 to block the airflow channel of the concealed vertical shaft 1.

[0023] Understandably, according to the above technical solution, intrinsic safety protection is achieved through a three-layer synergistic sealing structure. The basic pressure-bearing sealing layer resists the shaft pressure of the dark shaft, the intermediate isolation layer eliminates coal-oxygen contact, and the end-face sealing layer blocks external disturbances, forming a continuous and irreversible seal that completely cuts off the airflow channel, further avoiding the risk of ventilation system disorder and spontaneous combustion in the dark shaft.

[0024] Further, see Figure 2 The method for setting a pressure-bearing sealing layer includes: filling the protective steel plate 2 with concrete 3; It should be noted that before installing the protective steel plate 2 at the bottom of the underground shaft 1, if the underground shaft 1 has been shut down or abandoned for a long period of time due to production, geological, or other reasons after its use is completed, the coal, gangue, and other debris in the underground shaft 1 must be emptied, and the coal (gangue) discharge equipment must be dismantled. Then, the protective steel plate 2 is installed at the bottom of the underground shaft 1 to construct an initial foundation pressure barrier to withstand the vertical pressure of the solidified material 4 above, thereby preventing structural settlement and deformation. The concrete 3 injected above the protective steel plate 2 forms a rigid pressure-bearing matrix, eliminates air leakage channels at the bottom, and further reduces the air leakage rate.

[0025] Furthermore, in this embodiment, the thickness of the concrete 3 injected above the protective steel plate 2 is determined based on the depth of the underground shaft 1, specifically including: When the depth of the underground shaft 1 is less than the first preset depth, the thickness of the injection concrete 3 is greater than or equal to the product of the first preset depth and the first preset ratio. When the depth of the underground shaft 1 is greater than or equal to the first preset depth, the thickness of the injection concrete 3 is greater than or equal to the second preset depth.

[0026] Preferably, in this embodiment, the first preset depth is set to 5 meters, the first preset ratio is set to 50%, and the second preset depth is set to 2 meters. That is, when the depth of the underground shaft 1 is less than 5 meters, the thickness of the injected concrete 3 is greater than or equal to 2.5 meters; when the depth of the underground shaft 1 is greater than or equal to 5 meters, the thickness of the injected concrete 3 is greater than or equal to 2 meters. The above parameters have been experimentally verified by those skilled in the art, and can further improve the pressure resistance and sealing performance of the underground shaft 1. Furthermore, this thickness setting employs a proportional thickening design (≥50% depth) for shallow shafts (<5m) to ensure sufficient resistance to lateral pressure; and implements a minimum safe thickness (≥2m) for deep shafts (≥5m), ensuring compressive strength while avoiding material waste. This allows the three concrete layers to possess both structural safety and economy, greatly improving the foundation's pressure resistance.

[0027] Further, see Figure 2 The method of setting an intermediate isolation layer includes: filling the concrete 3 with curing material 4 up to the top of the dark vertical well 1; It should be noted that the curing material 4 in this embodiment can be an inorganic-based filling material or other curing material 4. By filling the curing material 4, a continuous inert barrier is formed, achieving a dual protective effect of physical isolation and chemical inertization. The dense filling completely occupies the wellbore space, blocking the airflow infiltration path and reducing the air leakage rate. The hydration reaction of inorganic-based materials (such as fly ash slurry) can consume free oxygen and release flame-retardant ions, further reducing the tendency of residual coal to oxidize and spontaneously combust. The intermediate isolation layer and the concrete 3 pressure-bearing layer form a rigid-flexible composite structure, which not only has good compressive strength but also good sealing effect.

[0028] The method for setting up an end-face sealing layer includes: laying an I-beam 5 at the top of the underground vertical shaft 1 and covering it with a cement layer for sealing. Through the above technical solution, the I-beam 5 skeleton forms a pressure-resistant support network, effectively dispersing the stress at the wellhead and preventing ground pressure deformation from damaging the sealing performance. Furthermore, the cement layer continuously covers and fills the gaps between the I-beam 5, completely blocking the infiltration channel of surface gas and further reducing the air leakage rate.

[0029] Preferably, in this embodiment, the protective steel plate 2 can be a Q235 steel plate with a thickness of not less than 20mm, and is fixed to the well wall rock mass by expansion bolts to ensure that its load-bearing capacity meets the weight requirements of the filling material above the well. The H-beam 5 of the end face sealing layer can be a 20# hot-rolled H-beam 5, welded into a grid frame according to the well diameter, with a frame spacing of not more than 300mm, and covered with 3 layers of 100mm thick C25 fine stone concrete. Expansion joints are set on the surface and filled with elastic sealing material to ensure the sealing integrity and structural stability of the end face.

[0030] In some specific embodiments, when the underground shaft 1 has a drainage requirement, a water guide pipe is pre-embedded at the protective steel plate 2 and a valve is installed for control. The water guide pipe can be a seamless steel pipe with a diameter of not less than 100mm. A filter screen must be installed at its inlet end to prevent impurities such as coal slag from clogging the pipe, and the outlet end extends to a water collection device outside the shaft. The valve should be a corrosion-resistant gate valve or ball valve with good sealing performance and ease of operation, so that the drainage volume can be adjusted at any time during daily maintenance. At the same time, the connection between the water guide pipe and the protective steel plate 2 must be sealed by full welding, and a waterproof concrete 3 reinforcement layer with a thickness of not less than 50mm should be poured around it to ensure that there is no leakage under water pressure, which satisfies the drainage function requirement without affecting the overall sealing performance of the end face sealing layer.

[0031] See Figure 3 In this embodiment, if temporary sealing is required, a reversible sealing structure is constructed within the concealed vertical shaft 1. Specifically, this involves installing a protective steel plate 2 at the lower opening of the shaft 1, and sequentially placing an elastic sealing layer and an end-face sealing layer above the protective steel plate 2. This temporary sealing scheme employs a three-layer progressive structure: the bottom protective steel plate 2 forms the initial sealing base, the middle elastic sealing layer provides a breakable dynamic barrier, and the top end-face sealing layer ensures airtight integrity. This satisfies the safety requirements for preventing air leakage during downtime while preserving efficient breaking conditions for subsequent reuse.

[0032] See Figure 3 The method for setting up an elastic pressure layer includes: injecting silica gel 6 above the protective steel plate 2, wherein the thickness of the injected silica gel 6 is determined according to the depth of the underground well 1, and the specific method includes: When the depth of the dark well 1 is less than the first preset depth, the thickness of the injected silica gel 6 is greater than or equal to the product of the first preset depth and the first preset ratio; When the depth of the dark well 1 is greater than or equal to the first preset depth, the thickness of the injected silica gel 6 is greater than or equal to the second preset depth.

[0033] It is understandable that injecting silica gel 6 above the protective steel plate 2 can construct an adaptive seal. After the silica gel 6 solidifies, it forms an elastic barrier that can adaptively compensate for the micro-deformation of the well barrel and completely seal the bottom air leakage channel. At the same time, during the reuse stage, it can be quickly dissolved and broken by water flushing without damaging the well barrel structure.

[0034] Preferably, in this embodiment, the first preset depth is set to 5 meters, the first preset ratio is set to 50%, and the second preset depth is set to 2 meters. That is, when the depth of the underground shaft 1 is less than 5 meters, the thickness of the injected silica gel 6 is greater than or equal to 2.5 meters; when the depth of the underground shaft 1 is greater than or equal to 5 meters, the thickness of the injected silica gel 6 is greater than or equal to 2 meters. The above parameters have been experimentally verified by those skilled in the art, and these settings can further improve the pressure resistance and sealing performance of the underground shaft 1, ensuring the sealing performance of the underground shaft 1 while guaranteeing that the material can be removed.

[0035] See Figure 3 The method for setting the end face sealing layer includes: laying I-beams 5 at the top of the dark vertical shaft 1 and covering it with a cement layer for sealing.

[0036] Preferably, the method for controlling the thickness of the injected silica gel layer 6 includes: using an intrinsically safe ultrasonic depth sensor for mining to monitor the filling height of the silica gel 6 in real time. The intrinsically safe ultrasonic depth sensor is vertically installed on the sidewall of the dark vertical shaft 1, and the monitoring data is transmitted to the surface control terminal in real time. When the thickness of the injected silica gel 6 reaches the required thickness, an automatic command to stop the injection of silica gel 6 is triggered. This technical solution, through a closed-loop intelligent control mechanism, utilizes the ultrasonic depth sensor to provide real-time feedback of the filling height data and automatically triggers the grouting termination command, ensuring that the thickness of the silica gel layer 6 accurately matches the well depth requirements. This significantly improves operational safety while eliminating errors from manual measurement, achieving a balance between sealing reliability, material economy, and construction efficiency.

[0037] Furthermore, the provision of an environmental monitoring interface for monitoring the gas inside the dark vertical shaft 1 includes: A gas monitoring bundle extending into the interior of the underground shaft 1 is laid at the lower opening of the shaft 1. The opening of the gas monitoring bundle is sealed, and the gas inside the gas monitoring bundle is periodically collected and its composition is analyzed to monitor the gas inside the underground shaft 1.

[0038] Understandably, the gas monitoring tube is extended into the interior of the dark vertical shaft 1, and gas samples are periodically collected and analyzed, for example... By monitoring changes in gas concentration, it can accurately capture early signs of spontaneous combustion. The pipe opening sealing design maintains the integrity of the sealing body, avoiding air leakage channels caused by traditional open-hole monitoring. In addition, corrosion-resistant bundled tube materials (such as polyethylene) can be used to withstand the humid environment of the wellbore, ensuring continuous monitoring capabilities during shutdown.

[0039] See Figure 2 and Figure 3 The working principle of this invention will be illustrated below with specific examples: In this example, when the underground shaft used in the coal mine is abandoned or shut down, it is effectively sealed and reused. Based on the shutdown and reuse time of underground shaft 1, it is managed by injecting non-combustible inorganic-based filling material into underground shaft 1 in layers. According to the reuse attributes of underground shaft 1, it is divided into permanent shutdown and temporary shutdown. For permanently shut-down underground shaft 1, a permanent sealing method is implemented; for temporarily shut-down underground shaft 1, a temporary sealing method is implemented. The specific implementation steps are as follows: (1) Permanently discontinue the use of underground vertical shafts Step 1: After the coal mine underground shaft 1 is used up, it will be stopped for a long time (scrapped) due to production, geology and other reasons. The coal, gangue and debris in the underground shaft 1 need to be emptied, the coal (gangue) discharge equipment needs to be dismantled, and a protective steel plate 2 needs to be installed at the bottom of the underground shaft 1. Step 2: Fill the bottom of the underground shaft 1 with concrete 3. If the depth of the underground shaft 1 is less than 5 meters, the filling thickness shall not be less than 50% of the depth of the underground shaft 1; if the depth of the underground shaft 1 is greater than or equal to 5 meters, the filling thickness shall not be less than 2 meters. Step 3: Fill the top of the concrete 3 in the underground shaft 1 with inorganic base filling material or other curing material 4; Step 4: I-beams 5 must be placed at the top of the underground shaft 1 and cement must be applied for sealing. If coal (gangue) or debris is present in the underground shaft 1 due to the influence of the site environment, cement must be injected to solidify the loose coal (gangue) or debris.

[0040] Step 5: For underground vertical wells that require drainage, a water guide pipe should be installed.

[0041] (2) Temporarily suspend the use of the underground shaft Step 1: For underground shaft 1 that has been out of service for more than one month, the coal, gangue and debris in underground shaft 1 must be emptied, the coal (gangue) discharge equipment must be dismantled, and a protective steel plate 2 must be installed at the bottom of underground shaft 1. Step 2: Inject silica gel 6 into the bottom of the underground shaft 1 for sealing. If the depth of the underground shaft 1 is less than 5 meters, the filling thickness shall not be less than 50% of the depth of the underground shaft 1; if the depth of the underground shaft 1 is greater than or equal to 5 meters, the filling thickness shall not be less than 2 meters. Step 3: I-beams 5 must be placed at the top of the underground shaft 1 and sealed with cement. Step 4: Lay a monitoring tube from the bottom of the underground shaft 1 into the shaft 1 and seal it with a plug. Take gas samples from the underground shaft 1 for analysis periodically.

[0042] It should be noted that this embodiment provides a method for sealing underground vertical shafts in coal mines. By selecting sealing modes based on the different reuse attributes of underground vertical shafts, this method effectively solves the sealing problem of abandoned or decommissioned underground vertical shafts in coal mines. For permanent decommissioning scenarios, a continuous and irreversible sealing structure is constructed to completely block the airflow channel, eliminating the risk of local ventilation system disorder caused by air leakage. For temporary decommissioning scenarios, a reversible sealing structure is adopted and an environmental monitoring interface is set up to achieve real-time monitoring of gas in the shaft while ensuring the reliability of the seal. This not only meets the safety requirements of preventing air leakage and spontaneous combustion during temporary decommissioning, but also provides convenient removal conditions for subsequent reuse, fundamentally eliminating the ventilation system imbalance and spontaneous combustion hazards caused by the mixed use of modes in traditional sealing processes.

[0043] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0044] The technical features described above can be combined arbitrarily. Although not all possible combinations of these technical features are described, any combination of these technical features should be considered to be covered by this specification, provided that such combination does not contain contradictions.

[0045] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for sealing a coal mine underground shaft, characterized in that, include: The sealing method is selected according to the reuse attribute of the dark vertical shaft (1), and the sealing method includes permanent sealing and temporary sealing; If it is to be permanently sealed, a continuous and irreversible sealing structure is constructed in the underground shaft (1) to block the airflow channel of the underground shaft (1); If it is a temporary sealing, a reversible sealing structure is constructed in the dark vertical shaft (1), and an environmental monitoring interface is set up to monitor the gas inside the dark vertical shaft (1).

2. The method for sealing underground vertical shafts in coal mines according to claim 1, characterized in that, The method of selecting the plugging method based on the reuse attribute of the dark vertical shaft (1) includes: If the reuse attribute of the underground shaft (1) is permanent disuse or abandonment, then the sealing method adopted is permanent sealing; If the reuse attribute of the dark vertical shaft (1) is temporary shutdown, then the sealing method adopted is temporary sealing.

3. The method for sealing a coal mine underground shaft according to claim 1, characterized in that, If the sealing is permanent, a continuous and irreversible sealing structure is constructed within the concealed vertical shaft (1) to block the airflow passage of the concealed vertical shaft (1), including: A protective steel plate (2) is installed at the lower opening of the underground shaft (1). A pressure-bearing sealing layer, an intermediate isolation layer and an end-face sealing layer are sequentially installed above the protective steel plate (2) to block the airflow channel of the underground shaft (1).

4. The method for sealing underground vertical shafts in coal mines according to claim 3, characterized in that, The method for setting the pressure-bearing sealing layer includes: filling the protective steel plate (2) with concrete (3); The method of setting the intermediate isolation layer includes: filling the concrete (3) with curing material (4) to the top of the dark vertical well (1); The method for setting the end face sealing layer includes: laying I-beams (5) at the top of the dark vertical shaft (1) and covering it with a cement layer for sealing.

5. The method for sealing underground vertical shafts in coal mines according to claim 4, characterized in that, The thickness of the concrete (3) injected above the protective steel plate (2) is determined based on the depth of the underground shaft (1), specifically including: When the depth of the underground shaft (1) is less than the first preset depth, the thickness of the injection concrete (3) is greater than or equal to the product of the first preset depth and the first preset ratio; When the depth of the underground shaft (1) is greater than or equal to the first preset depth, the thickness of the injection concrete (3) is greater than or equal to the second preset depth.

6. The method for sealing underground vertical shafts in coal mines according to claim 1, characterized in that, If the sealing is temporary, a reversible sealing structure is constructed within the underground shaft (1), including: A protective steel plate (2) is installed at the lower opening of the underground shaft (1), and an elastic sealing layer and an end face sealing layer are sequentially installed above the protective steel plate (2).

7. The method for sealing underground vertical shafts in coal mines according to claim 6, characterized in that, The method of setting the elastic pressure layer includes: injecting silica gel (6) above the protective steel plate (2), wherein the thickness of the injected silica gel (6) is determined according to the depth of the dark well (1); The method for setting the end face sealing layer includes: laying I-beams (5) at the top of the dark vertical shaft (1) and covering it with a cement layer for sealing.

8. The method for sealing underground vertical shafts in coal mines according to claim 7, characterized in that, The thickness of the injected silica gel (6) is determined according to the depth of the dark well (1), including: When the depth of the dark well (1) is less than the first preset depth, the thickness of the injected silica gel (6) is greater than or equal to the product of the first preset depth and the first preset ratio; When the depth of the dark well (1) is greater than or equal to the first preset depth, the thickness of the injected silica gel (6) is greater than or equal to the second preset depth.

9. The method for sealing a coal mine underground shaft according to claim 8, characterized in that, The method for controlling the thickness of the injected silica gel (6) layer includes: An intrinsically safe ultrasonic depth sensor for mining is used to monitor the filling height of silica gel (6) in real time. The intrinsically safe ultrasonic depth sensor for mining is vertically installed on the side wall of the dark shaft (1). The monitoring data is transmitted to the control terminal above ground in real time. When the thickness of the injected silica gel (6) reaches the required thickness, the command to stop injecting silica gel (6) is automatically triggered.

10. The method for sealing a coal mine underground shaft according to claim 1, characterized in that, The installation of an environmental monitoring interface to monitor the gas inside the dark vertical shaft (1) includes: A gas monitoring tube extending into the interior of the dark vertical shaft (1) is laid at the lower opening of the dark vertical shaft (1). The opening of the gas monitoring tube is sealed, and the gas inside the gas monitoring tube is periodically collected and the composition of the collected gas is analyzed in order to monitor the gas inside the dark vertical shaft (1).

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