Long-distance blind roadway tunneling ventilation method

Abstract

A long-distance blind roadway tunneling ventilation method comprises the steps that zoning is conducted according to the design range of tunneling, and a dirty air purification chamber is built in each zone; a concrete wall is tamped at the junction of the riverway and the dirty air purification chamber, and an air inlet and an air outlet are formed in the concrete wall; an extraction air duct and a relay fan are arranged in each partition, and iron air ducts with corresponding sizes and directions are pre-buried in the concrete wall according to the models and the mounting directions of the fans; a centrifugal relay fan is connected in series with an air outlet of the concrete wall; the air inlet of the concrete wall is connected with the extraction air duct of the working face and other air consumption equipment, the other end of the extraction air duct is connected with the relay fan of the other subarea, all dirty air is collected in time and discharged in a centralized mode, and it is guaranteed that the dirty air generated in the working area does not pollute fresh air of air consumption in the next step. The dirty air purification chamber is designed, dirty air is decelerated in the dirty air purification chamber, dirty air in a plurality of subareas of the whole single-end tunneling area is discharged in parallel, and the area ventilation effect that ventilation subareas in the single-end tunneling area are not independent is achieved.

Description

Technical Field

[0001] The invention relates to the field of ventilation in underground mining, and in particular to a ventilation method for long-distance dead-end tunnel excavation. Background Art

[0002] Underground mining is an important method for obtaining mineral resources, and underground mining is inseparable from single-headed tunneling. As shallow ore bodies are mined, exploration of deep ore bodies requires single-headed tunneling for several thousand meters. Long-distance single-headed tunneling is an important guarantee for deep mining. Currently, most mines use a combination of hybrid local mechanical ventilation and deep-hole ventilation for ventilation in long-distance single-headed tunneling. This has achieved certain results in different mines. However, when deep-hole ventilation cannot be used on the ground, hybrid local ventilation can only be used. The existing hybrid local ventilation does not meet the ventilation requirements of long-distance single-headed tunneling. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the defect of the prior art that it cannot meet the ventilation requirements of long-distance dead-end tunnel excavation, and to provide a long-distance dead-end tunnel excavation ventilation method.

[0004] The technical solution adopted by the present invention to solve its technical problem is a long-distance dead-end tunnel excavation ventilation method, the length of the long-distance dead-end tunnel is greater than 1 km, the excavation of the dead-end tunnel has a vein, a vein-through, and a dirty air purification chamber, the vein-through is vertically connected to the vein and has a gentle rounded corner at the connection point, the dirty air purification chamber is arranged on one side of the vein and is connected to the vein, and a wind tube and a fan are arranged in the vein. The ventilation method includes the following steps: S1. Divide the tunnel into sections according to the designed scope, and build a dirty air purification chamber in each section; S2. Concrete wall is built at the junction of the vein and the polluted air purification chamber, and air inlet and outlet are opened on the concrete wall; S3. An exhaust fan and a relay fan are installed in each partition, and iron fan tubes of corresponding size and direction are embedded in the concrete wall according to the model and installation direction of the fan; S4. Connect a centrifugal relay fan in series at the air outlet of the concrete wall to overcome the ventilation resistance of this section; S5. The air inlet of the concrete wall partitioned by the excavation working surface along the vein (or through the vein) is connected to the exhaust fan along the vein; the air outlet of the concrete wall is connected to the relay fan, and then connected to the exhaust duct to the next purification chamber. The air inlet of the concrete wall in the middle partition is connected to the exhaust duct and the exhaust duct of other air-using facilities; the air outlet of the concrete wall is connected to the relay fan, and then connected to the exhaust duct to the next polluted air purification chamber. The air inlet of the concrete wall partitioned by the underground exhaust port is connected to the exhaust duct and the exhaust duct of other air-using facilities; the air outlet of the concrete wall is connected to the relay fan, and then connected to the exhaust duct to the lower exhaust port; all polluted air in the single-headed excavation area is collected and discharged in a timely and centralized manner through each partition, so as to ensure that the polluted air generated in the working area does not pollute the fresh air used in the next step.

[0005] Furthermore, in step S1 , the length of the partition is determined according to the size of the ventilation resistance in the air duct.

[0006] Furthermore, in step S2, two air inlets are provided, one of which is connected to the exhaust duct of the previous partition, and the other is connected to the dirty air duct of other working surfaces or areas.

[0007] Furthermore, in step S2, the height of the air outlet on the concrete wall is higher than the height of the air inlet.

[0008] Furthermore, in step S5, one end of the exhaust fan in a partition is connected to the air inlet of the concrete wall on the same partition, and the other end is connected to the relay fan of the previous partition (or the exhaust fan along the vein working surface).

[0009] Furthermore, the method further includes step S6, installing a sewage air duct trap at the lowest point where the wind duct crosses the river or other lowest point in the lane, and installing a drain valve at the lower part of the trap to discharge the accumulated water in the wind duct in time.

[0010] Furthermore, in step S5, an exhaust fan (6) and a pressure fan (7) are set at the working surface along the vein (1), and the power of the exhaust fan (6) is greater than the power of the pressure fan (7), so as to deliver fresh air to the working surface along the vein (1) through the excavated vein.

[0011] In summary, the present invention has the following beneficial technical effects: The ventilation method for long-distance dead-end tunnel excavation of the present invention is not only suitable for ventilation of long-distance dead-end tunnel excavation, but also can be applied to the operation mode of opening multiple excavation working faces in long-distance dead-end tunnel excavation; the ventilation line of the present invention is simple, and a polluted air purification chamber is designed to slow down the polluted air inside it, and multiple partitioned polluted air in the entire dead-end tunneling area is connected in parallel in the exhaust duct and discharged together, and fresh air is sent to the vein working face through the excavated vein level tunnel, and the fresh air and polluted air do not interfere with each other, thereby realizing the regional ventilation effect of independent ventilation zones in the dead-end tunneling area; ventilation management is more convenient, and the polluted air is collected in zones and steps in long-distance dead-end tunnel excavation, thereby ensuring the full-area ventilation safety of long-distance dead-end tunnel excavation, bringing substantial increase to mine production efficiency, and bringing essential improvement to mine production safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram of the partitioning and structure of an embodiment of a long-distance dead-end tunnel excavation ventilation method of the present invention; Figure 2 This is a schematic diagram of pre-buried air ducts in a polluted air purification chamber according to an embodiment of a ventilation method for long-distance dead-end tunnel excavation of the present invention; Figure 3 It is a schematic diagram of a submerged bend in a sewage air duct in an embodiment of a ventilation method for long-distance dead-end tunnel excavation according to the present invention.

[0013] Description of reference numerals: 1. Along the vein; 2. Through the vein; 3. Dirty air purification chamber; 4. Through the vein working surface; 5. Along the vein working surface; 6. Exhaust fan; 7. Pressure fan; 8. Pressure air duct; 9. Exhaust air duct; 10. Relay fan; 11. Underground exhaust outlet; 12. Along the vein bottom plate; 13. Air inlet; 14. Along the vein top plate; 15. Air outlet; 16. Water trap of the dirty air duct; 17. Drain valve. DETAILED DESCRIPTION

[0014] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0015] Reference Figure 1 The underground structure in this embodiment is a dead-end tunnel excavation starting in the fourth middle section (elevation 480 meters) of a mining and processing plant compound, passing through a 22-degree inclined shaft (480 meters in length) to the tenth middle section (elevation 300 meters). Within the tenth middle section, there is over 1,200 meters of straight horizontal tunnel excavation. The excavation involves a vein 1 along the vein 1 and multiple vein-crossing sections 2. The excavation along the vein 1 has a vein 1 working surface, while the excavation through the vein 2 has a vein 2 working surface. Furthermore, there is a dirty air purification chamber 3, located on one side of the vein 1 along the vein 1.

[0016] The specific ventilation method includes the following steps: S1. Divide the 1st horizontal lane along the vein in the middle section of the tenth section into three zones: A, B, and C. Zone A is located next to the bottom station yard of the tenth middle section of the north inclined shaft, Zone B is near the temporary air compressor room underground, and Zone C is close to the design destination. Each zone is about 400 meters long. S2, such as Figure 2 As shown, according to the zoning, each of the three zones A, B, and C has a dirty air purification chamber 3, and the dirty air purification chambers 3 in the three zones are all abandoned drilling chambers. First, a 200mm thick concrete wall is rammed along the edge of the vein 1 in the empty area near the vein 1, that is, the intersection of the vein 1 and the dirty air purification chamber 3. The concrete wall is 2.6m high from the vein bottom plate 12 to the vein top plate 14, and its length is the length of the drilling chamber (about 4.5m). S3, such as Figure 2 As shown, one iron air duct is pre-buried in the concrete wall along the outlet direction of the air inlet 13 and two iron air ducts are pre-buried along the outlet direction of the air outlet 15 ; in addition, the height of the air outlet 15 is higher than that of the air inlet 13 .

[0017] S4. The air outlet 15 of the dirty air purification chamber 3 in area A is connected to an 11Kw centrifugal relay fan 10, the air outlet 15 of the dirty air purification chamber 3 in area B is connected to a 5.5Kw centrifugal relay fan 10, and the air outlet 15 of the dirty air purification chamber 3 in area C is connected to a 5.5Kw centrifugal relay fan 10. The relay fans 10 are used to overcome the ventilation resistance of each partition.

[0018] S5. The air inlet 13 of the dirty air purification chamber 3 in area A is connected to the dirty air duct of the water pump room and transformer station in the middle section 10 and the exhaust air duct 9 in area B. The air inlet 13 of the dirty air purification chamber 3 in area B is connected to the dirty air duct of the temporary air compressor room and the exhaust air duct 9 in area C. The air inlet 13 of the dirty air purification chamber 3 in area C is connected to the exhaust air duct 9 of the working surface along the vein 1 and the working surface through the vein 2.

[0019] Through S4 and S5, the polluted air from each sub-area within the dead-end excavation area is collected in stages. A closed polluted air return system, consisting of an exhaust duct 9, a polluted air purification chamber 3, and a relay fan 10, centrally discharges the polluted air from the dead-end excavation area to the surface through the mine's return air system via the underground exhaust outlet. Simultaneously, an 11 kW exhaust fan 6 and a 5.5 kW pressure fan 7 are installed at the working face along vein 1. The pressure differential generated by these two fans directs fresh air from the air intake lane in the fourth middle section through the inclined shaft to various air-using points along veins 1 through 10 (such as the pump room and power distribution room, and the working face along vein 1). Furthermore, relay fans 10 in each sub-area overcome ventilation resistance within each sub-area, ensuring sufficient return air power within the closed polluted air return system. The exhaust fan 6 also serves as the power source for pumping polluted air generated during operations along vein 1 into the exhaust duct 9.

[0020] S6, such as Figure 3As shown, the wind duct is at the lowest point of the river crossing or other lowest point in the tunnel. The dirty air generated by the working surface along the vein 1 is cooled by the exhaust duct 9 and the generated water flows into the water trap 16 of the dirty air duct when it reaches the lowest point. The operating personnel open the drain valve 17 every day to discharge the accumulated water in the water trap 16 of the dirty air duct to prevent the wind duct from being blocked by the accumulated water, thereby reducing the wind resistance of the wind duct and ensuring ventilation safety.

[0021] The ventilation of the working face along the vein during excavation operations is as follows: the polluted air generated by the operation at the working face along the vein 1 is sucked into the exhaust duct 9 by the exhaust fan 6, and then enters the polluted air purification chamber 3 through the air inlet 13 along the exhaust duct 9. The large cross-section of the polluted air purification chamber and the cross-section difference between the inlet and outlet ducts are used to slow down the polluted air, thereby purifying the polluted air; the polluted air is then discharged into the next partition by the centrifugal relay fan 10 at the air outlet 15, and circulates in sequence until it is discharged from the underground exhaust port 11 connected to the ground; and the fresh air is led to the middle section of the working face along the vein 1 through the inclined shaft.

[0022] In this embodiment, the positions of the air ducts are essentially the same, with the air duct entering the dirty air purification chamber 3 positioned higher than the air duct exiting the dirty air purification chamber 3. The opening of the pre-buried iron air duct is aligned with the direction of the air inlet and outlet ducts, reducing ventilation resistance. At the same time, a water trap structure is provided in the ventilation duct to reduce repeated equipment startup and ventilation costs. Two tunneling operations can be carried out in parallel within this area, reducing the time required for the two operations to be staggered. Furthermore, when not working underground, the middle relay fan 10 can be left unactivated, utilizing only the mixed ventilation pressure differential at the front tunneling working face to ensure that the temperature in this area does not rise.

[0023] At this point, the long-distance dead-end tunnel excavation ventilation of the mining and dressing plant has achieved the ventilation effect of non-independent zones through the regulation of the polluted air purification chamber 3; its polluted air is connected in parallel to the polluted air system (i.e., collected in steps) and concentrated, realizing timely collection in steps, and is concentrated and discharged from the underground exhaust port 11 connected to the ground (all polluted air in the tenth section is collected by the exhaust duct 9 of area A, and discharged to the upper mountain of the fourth section through the polluted air duct of the north inclined shaft, and discharged to the surface through the north wind shaft of the mining and dressing plant); its fresh air reaches various air-using points from the fourth section horizontal lane through the north inclined shaft and the tenth section horizontal lane, effectively solving the long-distance dead-end tunnel excavation ventilation of the tenth section of the north inclined shaft of the mining and dressing plant.

[0024] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Among them, the same parts are represented by the same figure numerals. It should be noted that the words "front", "rear", "left", "right", "up" and "down" used in the following description refer to directions in the accompanying drawings, and the words "inside" and "outside" refer to directions toward or away from the geometric center of a specific component, respectively. Therefore, all equivalent changes made according to the structure, shape, and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A ventilation method for long-distance dead-end tunnel excavation, wherein the length of the long-distance dead-end tunnel is greater than 1 km, and the excavation of the dead-end tunnel includes a vein (1), a through-vein (2), and a dirty air purification chamber (3), wherein the through-vein (2) is vertically connected to the vein (1) and has a gentle rounded corner at the connection point, and the dirty air purification chamber (3) is arranged on one side of the vein (1) and is connected to the vein (1), and a wind tube and a fan are arranged in the vein (1), characterized in that: The ventilation method includes the following steps: S1. Divide the area into zones according to the designed scope of excavation, and construct a polluted air purification chamber (3) in each zone; S2. Concrete walls are constructed at the junction of the vein (1) and the dirty air purification chamber (3), and air inlets (13) and air outlets (15) are provided on the concrete walls; S3. An exhaust fan (9) and a relay fan (10) are set in each partition, and iron fan tubes of corresponding size and direction are embedded in the concrete wall according to the model and installation direction of the fan; S4. A centrifugal relay fan (10) is connected in series at the air outlet (15) of the concrete wall to overcome the ventilation resistance of this section; S5. Connect the exhaust duct (9) of the working surface and other air-using equipment to the air inlet (13) of the concrete wall. At the same time, the other end of the exhaust duct (9) is connected to the relay fan (10) of another partition. All polluted air is collected and discharged in a timely manner, thereby ensuring that the polluted air generated in the working area does not pollute the fresh air used in the next step.

2. A long distance dead end tunnel excavation ventilation method according to claim 1, characterized in that: In step S1 , the length of the partition is determined according to the size of the ventilation resistance in the air duct.

3. A long distance dead end tunnel excavation ventilation method according to claim 1, characterized in that: In step S2, two air inlets (13) are provided, one of which is connected to the exhaust duct (9) of the previous partition, and the other is connected to the dirty air duct of other working surfaces or areas.

4. A long distance dead end tunnel excavation ventilation method according to claim 1, characterized in that: In step S2, the height of the air outlet (15) on the concrete wall is higher than the height of the air inlet (13).

5. A long distance dead end tunnel excavation ventilation method according to claim 1, characterized in that: In step S5, one end of the exhaust duct (9) in a partition is connected to the air inlet (13) of the concrete wall of the same partition, and the other end is connected to the relay fan (10) of the previous partition.

6. A long distance dead end tunnel excavation ventilation method according to claim 1, characterized in that: The method further comprises step S6, installing a sewage air pipe trap (16) at the lowest point where the wind duct crosses the river or at other lowest points in the laneway, and installing a drainage valve (17) at the lower part of the trap to timely discharge the accumulated water in the wind duct.

7. A long distance dead end tunnel excavation ventilation method according to claim 1, characterized in that: In step S5, an exhaust fan (6) and a pressure fan (7) are set on the working surface along the vein (1), and the power of the exhaust fan (6) is greater than the power of the pressure fan (7) to deliver fresh air to the working surface along the vein (1).

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