A construction method of a return air passage of a coal mine tunneling roadway

Abstract

This invention relates to the field of coal mining, and particularly to the field of underground ventilation in coal mines, specifically a method for constructing return air channels in coal mine tunneling roadways. The method includes: constructing chambers within the tunneling roadway; sealing the working face using anchor bolts, mesh support, or pillar and mesh support; drilling holes in the roadway side near the return airway of the mining area to connect with the return airway, forming ventilation holes; injecting casing into the ventilation holes; and installing pneumatic fans to increase airflow, thus quickly constructing a return air system and facilitating mine connection. This invention involves minimal engineering work, is safe and efficient, easy to operate, and cost-effective. It also enables the rapid construction of a return air system. After a full-pressure ventilation system is established at the working face, the drill holes can be temporarily sealed or permanently sealed using materials such as mud or cement.

Description

Technical Field

[0001] This invention relates to the field of coal mining, and particularly to the field of underground ventilation in coal mines, specifically a construction method for a return air passage in a coal mine tunneling roadway. Background Technology

[0002] Currently, when constructing ventilation systems at the openings of existing coal mine tunneling roadways, the method of connecting the tunneling roadway with the return airway of the mining area is adopted. Since the mining area roadways are generally arranged with three roadways (one intake airway, one return airway, and one track roadway), the connection between the tunneling roadway and the return airway of the mining area needs to pass through the mining area roadway, which requires the construction of a ventilation bridge or passing above or below the roof and floor of the original mining area roadway.

[0003] Whether constructing a ventilation bridge or passing over or under the roof of a tunnel, both methods involve a large amount of construction work, a long construction period, and high construction costs. Furthermore, there is a risk of misconnection, which can affect the ventilation system, easily cause airflow short circuits leading to accidents, and introduce unsafe factors into safety management. Safety management is challenging, manifested in: large workload, high cost, and significant safety management difficulties. Summary of the Invention

[0004] To address the shortcomings of the existing technology, this invention proposes a construction method for return air passages in coal mine tunneling roadways, which achieves the effects of small workload, safety and efficiency, ease of operation, cost savings, and rapid construction of a return air system.

[0005] To achieve the above objectives, the present invention provides a method for constructing a return air passage in a coal mine tunneling roadway, comprising the following steps:

[0006] S003: Drilling holes in the sidewall of the roadway near the return air of the mining area to connect with the return air roadway of the mining area and form a ventilation hole;

[0007] S004: Injection sleeve operation is performed inside the ventilation hole.

[0008] Furthermore, prior to step S003, the following steps are included:

[0009] S001: Construction of a chamber approximately 8-25m deep within the tunneling roadway;

[0010] S002: Use anchor bolts, mesh support, or pillar and mesh support to seal the working face;

[0011] Furthermore, in step S003, a hole is drilled in the sidewall of the tunnel near the return air roadway of the mining area to connect with the return air roadway of the mining area, forming a ventilation hole.

[0012] Furthermore, after step S004, the following steps are also included:

[0013] S005: In cases where multiple ventilation holes are designed, seal the opening of each ventilation hole after construction is completed.

[0014] S006: After the construction of multiple ventilation holes is completed, the ventilation holes are sealed. After the airflow stabilizes, the air volume is measured on site. Once the air volume is sufficient, the system can be put into use.

[0015] Furthermore, if the measured air volume in step S006 does not meet the requirements, the following steps are performed:

[0016] S007: Perform hole filling operation. If the site does not have the conditions for hole filling, install a fan to increase the airflow to meet the ventilation requirements.

[0017] Furthermore, in step S001, the length of the chamber is 10m or 20m.

[0018] Furthermore, in step S003, the borehole diameter is not less than 550mm, and to prevent collapse during drilling, the spacing between multiple ventilation holes is not less than 1.0m.

[0019] Furthermore, in step S003, the borehole diameter is 550mm or 900mm, and the spacing between the multiple ventilation holes is 1.0m.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] This invention is simple and labor-saving to operate, safe and efficient, easy to operate, cost-saving, and can quickly form a return air system, which is beneficial for mine connection. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of Embodiment 1 of the present invention;

[0023] Figure 2 This is a schematic diagram of Embodiment 2 of the present invention;

[0024] Figure 3 This is a diagram of a ventilation system for existing tunnel excavation techniques.

[0025] Explanation of reference numerals in the attached figures:

[0026] 1-Excavation roadway, 2-Ventilation hole, 3-Transport roadway, 4-Track roadway, 5-Return airway, 6-Connecting roadway, 7-Cavity, 8-Return airway. Detailed Implementation

[0027] Preferred embodiments of the invention will now be described in more detail. While preferred embodiments of the invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0028] Example 1:

[0029] like Figure 1 As shown, the underground section includes a transport roadway 3, a track roadway 4, a return air roadway 5, and a connecting roadway 6. A construction method for the return air passage in a coal mine tunneling roadway is provided, including the following steps:

[0030] S001: Construction of a chamber 7 (semi-coal and rock) approximately 8-25m deep within the No. 1 roadway of the tunneling roadway;

[0031] S002: Use anchor bolts, mesh support, or pillar and mesh support to seal the working face;

[0032] S003: First, install the drilling rig at the designated drilling position. Surveying technicians will measure the elevation of the connection point between the excavation roadway and the return air roadway 5 in the mining area. If there is a roadway in the middle of the two roadways, the elevation of the top and bottom plates of the roadway should also be considered to prevent accidental connection. Then, determine the drilling position, azimuth, dip angle and length on the sidewall of the excavation roadway near the return air roadway in the mining area. Drill a hole on the sidewall of the chamber 7 near the return air roadway in the mining area to connect with the return air roadway 5 in the mining area, forming ventilation hole 2. The diameter of the hole should not be less than 550mm. To prevent collapse during drilling, the spacing between multiple ventilation holes 2 should not be less than 1.0m.

[0033] S004: Injection sleeve operation is performed inside ventilation hole 2;

[0034] S005: In cases where multiple ventilation holes are designed, seal the opening of each ventilation hole after construction is completed;

[0035] S006: After all ventilation holes 2 have been constructed, the through holes of ventilation holes 2 shall be sealed. After the airflow stabilizes, the air volume shall be measured on site. If the air volume meets the requirements, the device can be put into use. If the air volume does not meet the requirements, proceed to step S007.

[0036] S007: Perform hole filling operation. If the site does not have the conditions for hole filling, install a fan to increase the airflow to meet the ventilation requirements.

[0037] In a more specific operation, in step S001, a 20-meter-long chamber 7 is constructed in the tunnel; in step S003, the borehole construction is designed with a diameter of 0.55m and a depth of 65m, with a total of 4 boreholes, spaced 1m apart, for a total construction length of 260m.

[0038] Comparison of Example 1 with the prior art:

[0039] According to existing technologies, such as Figure 3 As shown, the 22061 return air connecting roadway is 145m long and adopts a rectangular cross section with a combined anchor mesh and cable strap support method; the construction period is 28 days and 1540 man-days are required.

[0040] In Example 1, a 20m deep chamber 7 was constructed using a combination of anchor, mesh, and cable support; the construction period was 6 days, requiring 300 workers. The borehole construction involved drilling 4 holes with a diameter of φ0.55m and a depth of 65m, totaling 260m; the construction period was 20 days, requiring 180 workers.

[0041] See the table below for a detailed comparison:

[0042]

[0043] Therefore, it can be seen that the construction according to Embodiment 1 of the present invention saves 2 days of construction time and nearly half the cost compared with the existing tunnel construction technology, achieving the characteristics of small project volume, low investment, and high safety by using drilling method.

[0044] Example 2:

[0045] like Figure 2 As shown, the underground section includes a transport roadway 3, a track roadway 4, a return air roadway 5, and a connecting roadway 6. A construction method for the return air passage in a coal mine tunneling roadway is provided, including the following steps:

[0046] S001: A borehole is drilled in the side of the return air roadway 8 to connect with the return air roadway 5 in the mining area, forming a ventilation hole 2. The diameter of the borehole is not less than 550mm. To prevent collapse during the drilling, the spacing between multiple ventilation holes 2 is not less than 1.0m.

[0047] S002: Perform the injection sleeve operation inside ventilation hole 2 and seal the opening of ventilation hole 2;

[0048] S003: If there are multiple ventilation holes 2, after all ventilation holes 2 have been constructed, the through holes of ventilation holes 2 shall be sealed. After the airflow stabilizes, the air volume shall be measured on site. If the air volume meets the requirements, it can be put into use. If the air volume does not meet the requirements, proceed to step S004.

[0049] S004: Perform hole filling operation. If the site does not have the conditions for hole filling, install a fan to increase the airflow to meet the ventilation requirements.

[0050] In a more specific operation, in step S001, the borehole diameter for the tunnel construction is 0.9m, the depth is 30m, there are a total of 2 boreholes with a spacing of 1m, and the total construction length is 60m.

[0051] Comparison of Example 2 with the prior art:

[0052] Based on existing technology, the 2201 return air connecting tunnel is 30m long, with a construction period of 5 days (involving opening and locking, turning, and connection work), and a total construction cost of Z.

[0053] In Example 2, based on an aperture of φ900mm (wind speed calculated at 8m / s), the air volume is 305m³ / s. 3 Drilling at a rate of 600 m³ / min, based on a return air volume of 600 m³ / min at the working face. 3 Based on the calculation, two holes need to be drilled, each 30m long; the construction period is 2 days, which can save 3 days of construction time compared with the existing technology; the total construction cost is 1.78Z.

[0054] According to Embodiment 2 of the present invention, the construction period is reduced by 3 days and the cost is 1.78 times that of the existing roadway construction technology. However, with the marketization of operations, the promotion and application of boreholes in mine ventilation systems, and even their use in cable holes, drainage holes, etc., the unit price per meter of drilling is bound to decrease.

[0055] This invention is not only simple and labor-saving to operate, safe and efficient, easy to operate, and cost-effective, but also quickly forms a return air system, which is beneficial for mine connection. The number and diameter of the boreholes need to be calculated based on the required air volume and velocity at the working face. Once a full-pressure ventilation system is formed at the working face, the boreholes can be temporarily sealed or permanently plugged using materials such as mud or cement.

[0056] Future prospects of this invention:

[0057] (i) When the working face encounters the ventilation system constructed by the above-mentioned 22061 return air connecting roadway, the tunneling roadway is long, the cost is high, the labor is large, and the construction period is long; while the construction hole roadway of the present invention has low cost, less labor, and short construction period.

[0058] (ii) When the working face encounters the ventilation system constructed by the 2201 return air connecting roadway, the tunneling roadway is the same length as the borehole roadway. However, two borehole roadways need to be constructed. The construction cost of the borehole roadway is high, the labor is less, and the construction period is short. However, with the marketization of operations, the promotion and application of borehole roadways in mine ventilation systems, and even their use in cable holes, drainage holes, etc., the unit price per meter of drilling is bound to decrease, the cost will also decrease, and it will be beneficial to mine connection.

[0059] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A coal mine tunneling roadway return air passage construction method, characterized in that, Includes the following steps: S001: Construction of an 8-25m chamber within the tunneling roadway; S002: Use anchor bolts, mesh support, or pillar and mesh support to seal the working face; S003: First, install the drilling rig at the designated drilling position. The surveying technicians will measure the elevation of the connection point between the tunnel and the return airway (5) of the mining area. If there is a tunnel in the middle of the two tunnels, the elevation of the top and bottom plates of the tunnel should also be considered to prevent accidental connection. Then, determine the drilling position, azimuth, inclination and length on the side of the tunnel near the return airway of the mining area. Drill a hole in the side of the tunnel near the return airway of the mining area in the chamber (7) to connect with the return airway (5) of the mining area and form a ventilation hole (2). The diameter of the hole should not be less than 550mm. To prevent collapse during drilling, the spacing between multiple ventilation holes (2) should not be less than 1.0m. S004: Injection sleeve operation is performed inside the ventilation hole; S005: In cases where multiple ventilation holes are designed, seal the opening of each ventilation hole after construction is completed; S006: After the construction of multiple ventilation holes is completed, the ventilation holes are sealed. After the airflow stabilizes, the air volume is measured on site. Once the air volume is sufficient, the system can be put into use.

2. The coal mine tunneling roadway return air passage construction method according to claim 1, characterized in that, If the measured air volume in step S006 does not meet the requirements, proceed with the following steps: S007: Perform hole filling operation. If the site does not have the conditions for hole filling, install a fan to increase the airflow to meet the ventilation requirements.

3. The coal mine tunneling roadway return air passage construction method of claim 1, wherein, In step S001, the length of the chamber is 10m or 20m.

4. The coal mine tunneling roadway return air passage construction method according to claim 1, characterized in that, In step S003, the borehole diameter is not less than 550mm, and to prevent collapse during drilling, the spacing between multiple ventilation holes is not less than 1.0m.

5. The coal mine tunneling roadway return air passage construction method of claim 1, wherein, In step S003, the borehole diameter is 550mm or 900mm, and the spacing between the multiple ventilation holes is 1.0m.

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