A hierarchical ventilation system and control method for ultra-deep vertical shafts during construction

Abstract

The present invention discloses a graded ventilation system and control method for an ultra-deep vertical shaft during the construction period, and belongs to the field of mining engineering and ventilation technology. Sealed doors are installed at the connection between the horse head doors and the shaft wall at different depths in the shaft, so that the horse head doors and the space inside the stone door form a temporary relay air silo; fans are arranged on the surface and in each temporary relay air silo, and the fans arranged on the surface are connected to the spaces inside the temporary relay air silos at different levels through air ducts in sequence to form a chain transmission structure, until the air duct connected to the fan in the temporary relay air silo at the bottom of the shaft is connected to the bottom of the shaft; the ground air is sent from the fans arranged on the surface into the temporary relay air silos connected in series, and finally sent to the working face at the bottom of the shaft through the temporary relay air silo closest to the working face. In this system, the transmission resistance is effectively reduced, the wind pressure of each fan is constant, and fresh air is ensured to be delivered to the working face quickly and stably, thereby improving the safety of mine operations.

Description

Technical Field

[0001] The present invention belongs to the field of mining engineering and ventilation technology. Specifically, it relates to a hierarchical ventilation system and control method for ultra-deep vertical shafts during construction.

[0002] During coal mine shaft excavation operations, ventilation is crucial for ensuring worker safety and improving operational efficiency. Existing technologies rely on fans to deliver fresh air to the working face. However, due to the great depths of some mines, reaching as high as 2,000 meters, this leads to significant pressure loss and insufficient air volume during ventilation, compromising the safety of the working environment. Furthermore, conventional ventilation system designs are unable to effectively address the challenges posed by such long-distance ventilation. Therefore, a new ventilation solution is urgently needed to improve the long-distance ventilation of ultra-deep vertical shafts in coal mines.

[0003] The prior art with publication number CN202020151211.6 discloses a segmented ventilation system for an ultra-long tunnel, whose structure is: including a right-hole exhaust horizontal tunnel, a right-hole air supply horizontal tunnel, a left-hole exhaust horizontal tunnel and a left-hole air supply horizontal tunnel; each ventilation horizontal tunnel is connected to the ground separately, and does not intersect with each other, and only has an intersection with the main tunnel. The horizontal air supply distance is short, thereby reducing the air supply resistance of the underground tunnel. When ventilating an ultra-deep vertical shaft, the longitudinal ventilation is still difficult. Summary of the Invention

[0004] To address the shortcomings of existing technologies, a method for graded ventilation and control of ultra-deep vertical shafts during construction is provided. The space at the shaft's nacelle can be used as a temporary relay air silo, enabling relay air supply. The system features a simple structure and is easy to use.

[0005] In order to achieve the above technical objectives, the present invention discloses a graded ventilation system for an ultra-deep vertical shaft during the construction period, in which sealed doors are installed at the connections between the horse head doors and the shaft wall at different depths in the shaft, so that temporary relay air bins are formed inside the horse head doors and the stone doors; fans are arranged on the ground surface and in each temporary relay air bin, and the fans arranged on the ground surface are connected to the spaces in the temporary relay air bins at different horizontal heights in sequence through air ducts to form a chain transmission structure, until the air duct connected to the fan in the temporary relay air bin at the bottom of the shaft is connected to the bottom of the shaft; the ground air is sent from the fans arranged on the ground surface into the temporary relay air bins connected in series, and finally sent to the working face at the bottom of the shaft through the temporary relay air bin closest to the working face.

[0006] Furthermore, the air duct is extended and connected via flanges and bolts, making it easy to disassemble and assemble.

[0007] Furthermore, each temporary relay air silo is provided with a static pressure box and an environmental monitoring and control device for introducing airflow and stabilizing wind pressure. The fan is connected to the environmental monitoring and control device and is controlled by the environmental monitoring and control device.

[0008] Furthermore, the static pressure box is hoisted in the temporary relay air silo. Multiple supports are provided on the top of the static pressure box. The supports are connected to the top plate of the temporary relay air silo through steel wire ropes. Each support is connected to the steel wire rope through a pulley set. The temporary relay air silo environment monitoring and control device includes an electronic pressure gauge and a computer. The electronic pressure gauge transmits a pressure signal to the computer. The computer judges the pressure signal and feeds it back to the automatic control fan to control the speed. The signal is transmitted by a signal line.

[0009] Furthermore, the fan is a variable frequency fan, and the environmental monitoring and control device is connected to the fan through a signal line. The internal circuit of the fan controls the speed according to the signal of the environmental monitoring and control device, and accelerates or slows down the discharge of air flow by increasing or decreasing the speed to maintain a constant pressure in the temporary relay air bin.

[0010] Furthermore, according to the air volume requirements and the shaft structure, the horse head doors built on the left and right sides of the shaft were transformed into temporary relay air silos to form two parallel chain structures for supplying air to the bottom of the shaft, realizing double duct air supply.

[0011] Furthermore, when there are multiple horse head doors at the same horizontal height in the vertical shaft, the multiple horse head doors at the same horizontal height are converted into temporary relay air silos. At the same time, the multiple temporary relay air silos at the same horizontal height are connected in series through horizontally arranged air ducts for longitudinal graded ventilation. The fans installed in the temporary relay air silos only need to overcome the flow resistance brought by the horizontally arranged short air ducts.

[0012] Furthermore, the sealed door is a rolling door that can be opened and closed by remote control, and the edges of the rolling door are sealed as needed.

[0013] A control method for a graded ventilation system in an ultra-deep vertical shaft during construction, comprising the following steps:

[0014] S1. As the shaft is constructed, after the horse head door and the inner space of the stone gate are constructed in the shaft, waterproof composite materials are used to provide secondary support for the horse head door and the inner space of the stone gate to form a temporary relay air silo. When ventilation of a deeper area is required, the shaft of the horse head door and the inner space of the stone gate is temporarily closed with a sealing device to form a temporary relay air silo space;

[0015] S2. Install fans on the surface, and arrange fans, static pressure boxes, and environmental monitoring and control devices in the constructed first-level temporary relay air silo. Lead air ducts from the first-level temporary relay air silo to the working face;

[0016] S3. Using a surface-mounted fan to pressurize fresh air from the ground into the first-stage temporary relay air silo for temporary storage; using an environmental monitoring and control device to monitor the pressure value of the first-stage temporary relay air silo and compare it with a preset value, and issuing a judgment signal when the pressure value exceeds the preset value;

[0017] S4. Based on the current judgment signal, the fan in the first-stage temporary relay air bin is controlled to start, and the fresh air in the first-stage temporary relay air bin is delivered to the working face;

[0018] S5. As the shaft is constructed, S3 and S4 are circulated, and fresh air is sent into temporary relay air bins at different heights through air ducts in turn, and finally sent to the working surface at the bottom of the shaft, realizing graded air supply during construction of ultra-deep shafts. The fresh air flow transmitted to the bottom of the shaft by temporary relay air bins linked at all levels dilutes the polluted air at the bottom, and the polluted air at the bottom is discharged to the ground along the shaft.

[0019] Furthermore, the environmental monitoring and control device is used to monitor the pressure value of the temporary relay air silo. If the pressure value exceeds the outdoor environmental pressure value, the fan is controlled to increase the speed to speed up the gas discharge. Otherwise, the speed is reduced to maintain the current temporary relay air silo pressure constant.

[0020] Compared with the existing related technologies, the present invention has the following beneficial effects:

[0021] 1. This system has a wide range of applications and can be used for deep shaft ventilation in different situations to ensure that the working face always has a stable and fresh air flow.

[0022] 2. This system delivers fresh air to the working face in a segmented relay process, effectively improving air quality within the mine and providing a fresher, healthier working environment. This helps protect the health of miners and resolves the difficulty in ventilation at the working face caused by the significant resistance losses of long-distance air supply.

[0023] 3. This system uses the space of the horse head door as a temporary wind silo, which can efficiently utilize the space, improve the mining working environment and enhance work safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the positions of the vertical shaft and the temporary relay air silo in a specific embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of the air duct connection method in a specific embodiment of the present invention;

[0026] Figure 3 This is a schematic diagram of the static pressure box hoisting in a specific embodiment of the present invention;

[0027] Figure 4 This is a schematic diagram of a waterproof material in a specific embodiment of the present invention;

[0028] Figure 5 This is a schematic diagram of a rolling shutter door in a specific embodiment of the present invention;

[0029] Figure 6It is a schematic diagram of the environmental monitoring and control device and its operation in a specific embodiment of the present invention.

[0030] In the figure: 1-shaft, 2-temporary relay air silo, 3-fan, 4-air duct, 5-static pressure box, 6-environmental monitoring and control device, 7-rolling door, 8-waterproof material; 401 flange, 402 bolt, 501-wire rope, 502-pulley block; 503-support, 601-electronic pressure gauge, 602-computer, 603-signal line. DETAILED DESCRIPTION

[0031] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0032] like Figure 1 As shown, a system for remote, graded ventilation of an ultra-deep vertical shaft under construction includes a shaft 1, a temporary relay air silo 2, a fan 3, an air duct 4, a static pressure box 5, an environmental monitoring and control device 6, a rolling door 7, and waterproofing material 8. If dual-duct ventilation is used, a temporary relay air silo can be arranged in a symmetrical position.

[0033] A method for graded ventilation and control during the construction period of an ultra-deep vertical shaft includes a temporary relay air silo established using the shaft's gantries. The temporary relay air silo houses a temporary relay air silo environmental monitoring and control device. The temporary relay air silo is supported by waterproof materials and has temporary enclosure material at its connection to the shaft. An air duct enters from above the temporary relay air silo and connects to a static pressure box and a fan, with the fan outlet connected to the air duct. The temporary relay air silos can be arranged symmetrically, and when air is supplied by two ducts, the corresponding temporary relay air silos can be used to relay air supply.

[0034] The air duct is made of several identical shorter fiberglass reinforced plastic air ducts connected by flanges. The diameter of the air duct is determined according to the required air flow of the work surface. The fiberglass reinforced plastic air duct for air inlet is connected to the temporary relay air silo through a 90° elbow.

[0035] The static pressure box 5 is made of galvanized steel plate and is hoisted above the temporary relay air silo 2 to reduce the dynamic pressure of the incoming air, increase the static pressure, stabilize the airflow and reduce vibration. The static pressure box 4 is hoisted on the upper part of the temporary relay air silo by a wire rope.

[0036] Fan 3 is a local ventilation fan for mines, which has a signal receiving function and a PLC automatic control system.

[0037] The FRP duct for air outlet is also made of several shorter FRP ducts connected by flanges, and a 90° elbow is used for temporary relay air bin connection.

[0038] The temporary relay wind silo constructed within the horse-head gate space requires support with waterproofing materials. A temporary rolling shutter door is installed at the entrance, and a pressure monitoring system is installed inside the temporary relay wind silo to monitor the indoor pressure. After the temporary relay wind silo space is completed, anchor spraying support will be implemented in this area. A flexible and water-resistant polyurethane-polyurea composite material will be sprayed as a waterproof layer to prevent water seepage. A temporary rolling shutter door will be installed near the shaft to temporarily seal the space.

[0039] The air duct 4 is attached to the cylinder wall through a bracket in the shaft 1. The temporary rolling shutter door is cut to reserve an air duct channel.

[0040] The temporary relay wind silo environment monitoring and control device consists of an electronic pressure gauge, a signal transmission line, and a computer. It has the function of transmitting pressure signals to measure the relative pressure in the room in real time and convert it into a signal to transmit to the computer. The computer program determines whether the front signal is greater than (or less than) the preset value, and transmits the judgment result signal to the fan, and the speed is controlled by the automatic system.

[0041] like Figure 2 As shown, the air duct 4 is composed of several short air tubes connected by flanges 401 to extend the length of the air duct, and the flanges 401 are connected and reinforced by bolts 402.

[0042] like Figure 3 As shown, the static pressure box 5 is made of stainless steel plate, is hoisted from the top by a steel wire rope 501 and a pulley block 502, and is fixed by a support 503.

[0043] like Figure 4 As shown, the main component of the waterproof material 8 is a polyurethane-polyurea composite material, which is sprayed on the supported foundation to waterproof the space.

[0044] like Figure 5 As shown, the rolling shutter door 7 is cut out from an ordinary rolling shutter door to reserve air duct space, and is electrically controlled to rise and fall.

[0045] like Figure 6 As shown, the temporary relay air silo environment monitoring and control device 6 is integrated with an electronic pressure gauge 601, a computer 602, and a signal line 603. The electronic pressure gauge measures the indoor pressure and transmits the pressure signal to the computer for program judgment. The computer feeds the judgment result signal back to the fan to control the speed and maintain the indoor pressure.

[0046] The temporary relay air bin space is provided with secondary waterproof support, and waterproof material 8 mainly composed of polyurethane and polyurea is sprayed. Then the rolling shutter door 7 is lowered to temporarily close the temporary relay air bin space. Fresh air flows from the ground through the air duct 4, through the rolling shutter door 7 and into the temporary relay air bin, and enters the static pressure box 5 for noise reduction and vibration reduction. The pressure detection device 6 is responsible for monitoring and transmitting the pressure signal, that is, the electronic pressure gauge 601 monitors the real-time pressure in the room and transmits the pressure signal to the computer through the signal line 603. The computer sets a judgment program and sends a signal to the computer at intervals. The feedback signal from fan 3 is adjusted according to the on-site conditions and can be 1-2 minutes. If the pressure value at this time is greater than the external ambient pressure, a control signal is transmitted to fan 3 to increase the speed of fan 3 to speed up gas discharge. The control logic is: for every 10% increase in the pressure value, the fan speed is controlled to increase by 3.5%. Similarly, if the pressure signal value fed back by the pressure gauge is less than the external ambient pressure, a control signal is transmitted to fan 3 to reduce the speed of fan 3 to slow down gas discharge. The control logic is: for a 10% decrease in the pressure value, the fan speed is controlled to decrease by 4%. In this way, the fresh air entering from above the ground flows into the temporary relay air silo 2 for temporary storage, and is then extracted to supply air to the working surface below. When using double ducts for air supply, it is only necessary to arrange another temporary relay air silo 2 at a symmetrical position, using the same support method and automatic control method. Through this method, the vertical shaft is divided into sections, and the built horse head door space is used as a temporary relay air silo to store and transfer the fresh air from the ground. In this graded ventilation mode, the fans only need to overcome the resistance of their relatively short wind ducts to transport the airflow to the working face, solving the problem of large pressure loss caused by the excessive length of the wind duct in long-distance air supply in the past.

[0047] During operation, the space of the shaft horse head door is used as a temporary relay air bin 2, and the ground fan 3 supplies air to the working face below. A forced-in ventilation method is adopted, and fresh air enters the first temporary relay air bin 2 under the action of the ground fan 3 and is stored. When the working face is excavated downward, the fan 3 in the temporary relay air bin 2 is turned on to supply air to the working face below. In shaft ventilation, taking single duct air supply as an example, several temporary relay air bins 2 can be built using secondary support and waterproofing materials in the horse head door space according to the current excavation situation. The rolling shutter door 7 is used to temporarily close the space to form a temporary relay air bin 2. Several temporary relay air bins are used for longitudinal graded ventilation. At this time, the ground fan 3 is turned on and continuously supplies air to the first temporary relay air bin 2. The electronic pressure gauge set in the temporary relay air bin 2 transmits the pressure signal to the computer via the signal line. The computer has a built-in judgment program that compares the front pressure signal with the external environment pressure to monitor the relative pressure value in the temporary relay air bin 2. When the fan input signal value is greater than 10% of the reference pressure, the computer outputs a signal and transmits a command via the signal line to control the fan 3 to increase the speed to increase the suction volume. When the input signal value is negative and the absolute value is less than 10% of the reference pressure, the signal line transmits a command to control the fan 3 to reduce the speed and reduce the suction volume to maintain a constant pressure in the temporary relay air bin 2, so that the temporary relay air bin 2 is always in a dynamic full air state. The wind flow that is replenished from the ground to the first temporary relay air bin 2 is transferred here and continues to be transmitted downward. When the wind flow reaches the second temporary relay air bin 2, the same automatic control method and principle are used to continue to convey the wind flow to the working face below. In this mode, the wind flow of each temporary relay air bin 2 is connected in series in stages to achieve relay air supply. The fans 3 between the temporary relay air bins 2 only need to overcome the resistance of the shorter air ducts between the temporary relay air bins, solving the problem of excessive ventilation resistance over long distances. When the mine is deep and a large amount of air is required, and double ducts are needed for air supply, the horse head door space can be symmetrically arranged as a temporary relay air bin 2, and the fans 3 on both sides can use the corresponding temporary relay air bins for relay air supply.

Claims

1. A hierarchical ventilation system for ultra-deep shafts during construction, characterized by: Sealing doors are installed at the connection points between the horse-head doors and the shaft wall at different depths in the shaft (1), so that the horse-head doors and the space inside the stone door form a temporary relay wind silo (2); fans (3) are arranged on the ground surface and in each temporary relay wind silo (2); the fans (3) arranged on the ground surface are sequentially connected to the spaces inside the temporary relay wind silos (2) at different levels through air ducts (4) to form a chain transmission structure, until the air duct (4) connected to the fan (3) in the temporary relay wind silo (2) at the bottom of the shaft (1) is connected to the shaft bottom; the ground air is sequentially sent from the fans (3) arranged on the ground surface into the temporary relay wind silos (2) connected in series, and finally sent to the working face at the bottom of the shaft through the temporary relay wind silo (2) closest to the working face; Each temporary relay wind silo (2) is provided with a static pressure box (5) for introducing wind flow into it and stabilizing wind pressure, and an environmental monitoring and control device (6). The fan (3) is connected to the environmental monitoring and control device (6), and the fan (3) is controlled by the environmental monitoring and control device (6). The static pressure box (5) is hoisted in the temporary relay air silo (2). A plurality of supports (503) are provided on the top of the static pressure box (5). The supports (503) are connected to the top plate of the temporary relay air silo (2) through steel wire ropes (501). Each support (503) is connected to the steel wire rope (501) through a pulley block (502). The temporary relay air silo environment monitoring and control device (6) includes an electronic pressure gauge (601) and a computer (602). The electronic pressure gauge (601) transmits a pressure signal to the computer (602). The computer (602) judges the pressure signal and feeds it back to the automatic control fan (3) to control the speed. The signal is transmitted via the signal line (603).

2. The ultra-deep vertical shaft graded ventilation system during construction according to claim 1 is characterized in that: The air duct (4) is extended and connected via a flange (401) and bolts (402) for easy disassembly and assembly.

3. The ultra-deep vertical shaft graded ventilation system during construction according to claim 1 is characterized in that: The fan (3) is a variable frequency fan. The environmental monitoring and control device (6) is connected to the fan (3) via a signal line (603). The internal circuit of the fan (3) controls the rotation speed according to the signal of the environmental monitoring and control device (6). The speed is increased or decreased to accelerate or slow down the discharge of the air flow, so as to maintain a constant pressure in the temporary relay air bin (2).

4. The ultra-deep vertical shaft graded ventilation system during construction according to claim 1 is characterized in that: According to the air volume requirement and the structure of the shaft (1), the existing horse head doors on the left and right sides of the shaft (1) are transformed into temporary relay air bins (2) to form two parallel chain structures for supplying air to the bottom of the shaft, thereby realizing double duct air supply.

5. The ultra-deep vertical shaft graded ventilation system during construction according to claim 1 is characterized in that: When there are multiple horse-head doors at the same level in the shaft (1), the multiple horse-head doors at the same level are transformed into temporary relay air bins (2), and the multiple temporary relay air bins (2) at the same level are connected in series through horizontally arranged air ducts (4) to perform longitudinal graded ventilation. The fan (3) arranged in the temporary relay air bin (2) only needs to overcome the flow resistance caused by the horizontally arranged short air duct.

6. The ultra-deep vertical shaft graded ventilation system during construction period according to claim 1 is characterized in that: The sealed door is a rolling shutter door (7) that can be opened and closed remotely, and the edges of the rolling shutter door (7) are sealed as needed.

7. A control method for the ultra-deep vertical shaft graded ventilation system during construction period using the method of claim 1, characterized in that: The specific steps are as follows: S1. With the construction of the vertical shaft (1), after the space inside the horse head door is constructed in the vertical shaft (1), the space inside the horse head door is secondary supported by a waterproof composite material (8) to form a temporary relay wind bunker (2). When a deeper area needs to be ventilated, the shaft inside the horse head door is temporarily closed by a closing device to form a temporary relay wind bunker (2); S2, a fan (3) is installed on the surface, and the fan (3), static pressure box (5) and environmental monitoring and control device (6) are arranged in the constructed first-level temporary relay air silo (2), and an air duct (4) is led out from the first-level temporary relay air silo (2) to the working face; S3, using a fan (3) installed on the ground surface to press the fresh air flow from the ground into the first-stage temporary relay air bin (2) for temporary storage; using an environmental monitoring and control device (6) to monitor the pressure value of the first-stage temporary relay air bin (2), and compare it with a preset value, and when the pressure value exceeds the preset value, a judgment signal is issued; S4, according to the current judgment signal, controlling the fan (3) in the first-stage temporary relay air bin (2) to start, and delivering the fresh air in the first-stage temporary relay air bin (2) into the working face; S5. As the shaft (1) is constructed, S3 and S4 are circulated, and fresh air is sequentially sent through the air duct (4) to the temporary relay air bins (2) at different heights, and finally sent to the working surface at the bottom of the shaft, realizing ultra-deep vertical construction while supplying air in stages. The fresh air flow transmitted to the bottom of the shaft by the temporary relay air bins (2) linked at all levels dilutes the polluted air at the bottom, and the polluted air at the bottom is discharged to the ground along the shaft (1).

8. The control method according to claim 7, wherein: The pressure value of the temporary relay air bin (2) is monitored by the environmental monitoring and control device (6). If the pressure value exceeds the outdoor environmental pressure value, the fan (3) is controlled to increase the speed to accelerate the gas discharge. Otherwise, the speed is reduced to maintain the current pressure of the temporary relay air bin (2) constant.

Images