A device for monitoring the pressure balance and storage capacity of underground reservoirs converted from abandoned mines

Abstract

The present invention is a device for monitoring the pressure balance and storage capacity of underground reservoirs rebuilt from abandoned mines. The device includes a main pipeline and various primary branch pipelines and secondary branch pipes. The main pipeline is arranged at the ventilation lane or return air lane of the abandoned mine, and a primary branch pipeline is arranged at each lane entrance. All primary branch pipelines are connected to the main pipeline. A number of secondary branch pipes are arranged at different heights in the goaf and / or lanes through which the lane passes, and the secondary branch pipes are connected to the corresponding primary branch pipes. The upper port of each secondary branch pipe is located at the elevation position where the water level needs to be monitored in the goaf or lane. The upper port of the secondary branch pipe is equipped with a water immersion sensor and is fixed to the roof of the goaf or lane by connecting an anti-collision structure. A pumping unit is arranged at the junction of the secondary branch pipe and the primary branch pipe. The device can integrate the balance of air pressure and atmospheric pressure above the reservoir during the filling and discharge process with storage capacity monitoring.

Description

Technical Field

[0001] The invention relates to the field of development and utilization of abandoned mines, and in particular to a gas pressure balance and storage capacity monitoring device for underground reservoirs converted from abandoned mines. Background Art

[0002] Coal is my country's basic energy source, and most of it is mined underground. During the coal mining process, many tunnels and chambers will be dug, and huge goafs will be formed after the coal mining is completed. With the end of coal mining, the mines will be closed, and huge underground spaces will be created. At the same time, the state is also rectifying small and medium-sized coal mines, and some non-compliant mines with hidden dangers have also been closed one after another. In 2018, the number of coal mines in my country decreased from more than 14,000 in the early days to about 5,800. With the deepening of de-capacity, more mines will be closed. By 2030, the number of abandoned mines will reach 15,000, and the underground volume of goafs will reach 23.4 billion cubic meters. How to use these abandoned mines is an important issue related to environmental protection and resource utilization.

[0003] At present, a feasible solution for utilizing abandoned mines is to transform them into pumped storage power stations and use the goaf of abandoned mines to store water resources. Pumped storage power stations in coal mines mainly convert energy between water potential energy, electrical energy and mechanical energy. When electricity consumption is low, water is pumped from the lower reservoir to the upper reservoir with the help of excess power from the power grid, and water is released to generate electricity during peak electricity consumption. At present, the construction of pumped storage power stations with the help of abandoned mines is not only of great social significance in terms of environmental governance, coal mine transformation, and mining population resettlement, but also has strong feasibility at the technical and economic levels. It can be seen that pumped storage power stations in abandoned coal mines have good development prospects. However, due to the complexity of underground mine tunnels and goafs, the roof heights of various places are different. During the water filling process, the roofs of the higher-positioned tunnels and goafs will form high-pressure air columns due to the rise of the horizontal plane, so that the higher-positioned tunnels and goafs cannot be fully filled with water, resulting in a huge waste of underground space. Therefore, the influence of high pressure during water filling and negative pressure during drainage caused by the inconsistent height of the tunnel and goaf roof must be eliminated. At the same time, in order to monitor the reservoir capacity in real time and achieve the purpose of precise control, a reservoir capacity monitoring device must be installed. The existing technical solutions either do not consider how to eliminate the negative pressure generated in the goaf during drainage or do not have a device for reservoir capacity monitoring. Summary of the invention

[0004] In view of the deficiencies in the prior art, the technical problem that the present invention intends to solve is to provide an air pressure balance and storage capacity monitoring device for an underground reservoir converted from an abandoned mine, which integrates the balance of air pressure and atmospheric pressure above the reservoir during the filling and draining process with storage capacity monitoring.

[0005] The technical solution adopted by the present invention to solve the technical problem is: to provide an abandoned mine reconstruction underground reservoir air pressure balance and storage capacity monitoring device, which is used to balance the atmospheric pressure of each tunnel and goaf area with the external environment and monitor the storage capacity. The device includes a main pipeline and each first-level branch pipeline 0202 and a second-level branch pipe 004. The main pipeline is set at the ventilation tunnel or return air tunnel of the abandoned mine, and a first-level branch pipeline 0202 is set at each tunnel entrance. All first-level branch pipelines are connected to the main pipeline. The first-level branch pipeline is arranged along the tunnel. A number of second-level branch pipes 004 are set at different heights in the goaf and / or tunnel passed by the tunnel. The second-level branch pipes are all connected to the corresponding first-level branch pipelines. The installation height of the upper end of the secondary branch pipe in the same goaf or the same tunnel is different, which is used to monitor and balance the air pressure at different heights in the goaf or tunnel. The number of secondary branch pipes in each goaf is not necessarily the same, and they are arranged according to the storage capacity of the goaf. Secondary branch pipes must be set at the elevation position close to the roof of the goaf; the upper end of the main pipeline is connected to the external environment, and branch pipes are led out from the main pipeline at the tunnel position. The main pipeline goes deep into each tunnel entrance through the ventilation tunnel, and then each first-level branch pipe 0202 and second-level branch pipe are connected to each tunnel and goaf 001 that need to balance the air pressure, and the tunnel and each goaf are connected together with the first-level branch pipe 0202 and the second-level branch pipe;

[0006] The upper end of each secondary branch pipe is located at an elevation position in the goaf or tunnel where the water level needs to be monitored, and the upper end of each secondary branch pipe is fixed to the roof of the goaf or tunnel by connecting the anti-collision structure;

[0007] The lowest point where the secondary branch pipe meets the primary branch pipe is connected to the pumping unit 003 through a hose. At the same time, a water immersion sensor is installed at the upper port of each secondary branch pipe to monitor the water level at different heights of the goaf; the water immersion sensor 014 and the pumping unit 003 are electrically connected to the controller 017 in the control room.

[0008] The connecting anti-collision structure includes a hard conical shield 011, a connecting rod 010 and a connecting piece 014. One end of the connecting rod is detachably fixed to the top plate of the goaf or tunnel, and the other end is welded to the tip of the conical shield. The lower part of the conical shield is fixed to the upper port of the secondary branch pipe through the connecting piece, ensuring that the lower end surface of the conical shield can cover the upper port of the secondary branch pipe, and the upper port of the secondary branch pipe can communicate with the space in the goaf or tunnel.

[0009] There are multiple main pipelines, which are responsible for air pressure balance and storage capacity monitoring in the tunnels and goafs nearby. At the same time, a pumping unit is set at the intersection of the main pipeline and the first-level branch pipeline according to actual needs; a filter screen 012 is set at the port of the main pipeline and the second-level branch pipe to prevent the pipeline from being blocked. The filter screen 12 is made of fine iron wire material, and an anti-shielding structure is set above the main pipeline to ensure that when it is connected to the external environmental air pressure, it can prevent hard objects from damaging the pipeline.

[0010] The working principle of the device is as follows: first, the abandoned mine is surveyed, the elevation of each point to be monitored is determined, the number of the elevation point position in each goaf and tunnel is recorded, and the cross-sectional area at the elevation position of each point is recorded, and the relationship between different elevations and capacities is obtained so as to obtain the current volume of the mine from the elevation data;

[0011] Connect the secondary branch pipe through the tunnel to the goaf 001 where the gas pressure needs to be balanced or the highest point of the tunnel and the elevation position of the water level that needs to be monitored;

[0012] The entire pipeline system including the main pipeline, the first-level branch pipeline and the second-level branch pipeline has three functions: first, the goaf area where the air pressure needs to be balanced is connected to the outside air through the pipeline system, thereby eliminating the air column generated by the water filling in the goaf; second, after the abandoned mine is filled with water, the water will contact the water immersion sensor contacts from low to high through the upper port 004 of each second-level branch pipe, thereby activating the water immersion sensor, obtaining the actual water level line of the reservoir and thus obtaining the storage capacity of the reservoir; third, due to the existence of negative pressure, the flow of water out of the reservoir is slowed down. The setting of multiple second-level branch pipes of different heights in the goaf can eliminate the negative pressure caused by the drop in water level after pumping. Specifically: the upper port of the second-level branch pipe is set at the top plate of the goaf, which can be connected to the ventilation tunnel or the outside world to balance the negative pressure. At the same time, the second-level branch pipe that was not submerged by water before precipitation can also balance the negative pressure.

[0013] According to the storage capacity of the goaf and the elevation distribution in the goaf, set up secondary branch pipes with different elevations; or set up a secondary branch pipe every 3cm height change, and place a water immersion sensor at the top of the secondary branch pipe.

[0014] The present invention also protects a method for monitoring the pressure balance and storage capacity of an underground reservoir rebuilt from an abandoned mine. The monitoring method uses the above-mentioned monitoring device, and the specific steps of the method are:

[0015] Before installing the pipeline, it is necessary to detect the elevation of each tunnel and goaf, and mark all the elevations that need to be monitored. i And measure the area S of the cross section at each elevation i , which also includes the area of ​​the bottom of the tunnel and goaf; through the geological survey data completed in advance, the elevation that needs to be monitored in the goaf or tunnel is obtained, and the two adjacent elevation points are recorded as hi 、h i-1 , i represents the elevation point number in the current goaf or tunnel, the bottom of the goaf is numbered 0, h 0 is 0, and is numbered 1, 2, ..., i-1, i, ..., n from bottom to top according to the height, where n is the number of water immersion sensors in the goaf or tunnel;

[0016] The controller obtains the data and corresponding number of the water immersion sensor in real time. At the same time, the controller stores the area data of the cross section of the corresponding elevation of the corresponding goaf or tunnel. According to the formula It can calculate the current reservoir capacity of each goaf or tunnel to be monitored, and obtain the reservoir capacity of the current mine by summing the current reservoir capacities of all monitored goaf or tunnels, and display the current working water immersion sensors of each goaf or tunnel and the corresponding numbers, the current reservoir capacity of each goaf or tunnel, and the reservoir capacity of the current mine on the display screen connected to the controller;

[0017] Where V m is the current reservoir capacity in the goaf or tunnel, m is the number of the water sensor at the highest point triggered by the current water level, and m is not greater than n;

[0018] When water is injected, the water level gradually increases. During the process of water level increase, the water immersion sensor that is triggered first works to give the current elevation and corresponding number. The current reservoir capacity can be calculated through the above formula;

[0019] As the water surface gradually rises, the gas first passes through the upper ports of all the secondary branch pipes and connects to the outside world. The water surface continues to rise, submerging the upper port of the lowest secondary branch pipe, and connecting to the outside world through the upper ports of the remaining secondary branch pipes. When the water surface reaches the lower part of the upper port of the highest secondary branch pipe, only the highest secondary branch pipe is connected to the outside world, discharging the gas in the goaf and achieving the effect of balancing the gas pressure.

[0020] When water is released, since most of the water sensors are submerged, the submerged water sensors work, and the number of the water sensor at the highest point triggered is recorded. The current reservoir capacity is calculated according to the above formula. When the water level gradually decreases, the water sensor at the highest point currently triggered gradually stops working, and the reservoir capacity is calculated according to the number of the water sensor at the next highest point.

[0021] When the water surface line at the lower part of the upper port of the highest secondary branch pipe drops to the initial water surface line, outside air enters the tunnel and the goaf from the tunnel and the pipelines to balance the negative pressure caused by the drop in water level. The pumping unit 003 installed at the intersection of each primary branch pipe and the secondary branch pipe further removes the accumulated water inside the pipeline system after the mine is pumped out, so as not to affect the balance of air pressure in the goaf during the next water filling.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention provides an integrated device that integrates the functions of balancing air pressure, eliminating negative pressure generated during drainage, and monitoring reservoir capacity. Through the geological survey data completed in advance, the water level elevation monitored by the instrument is converted into the reservoir capacity so that the reservoir capacity can be monitored in real time. One end of each branch pipeline 0202 is connected to the lane or goaf 001 where the air pressure needs to be balanced and the elevation needs to be monitored, and the other end is connected to the main pipeline 0201 connected to the lane and goaf introduced through the lane or ventilation lane, thereby eliminating the influence of high pressure during water filling and negative pressure during drainage. The controller 017 controls the personnel indoors to monitor and control the reservoir capacity. It overcomes the disadvantages of the prior art that multiple sets of equipment need to be designed and repeatedly installed to achieve the above functions at the same time, and has the advantages of high degree of automation, high equipment integration, and convenient construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic cross-sectional structure diagram of an embodiment of a device for monitoring air pressure balance and storage capacity of an underground reservoir converted from an abandoned mine according to the present invention.

[0025] Figure 2 It is a schematic diagram of the fixing method of the pipeline in the present invention.

[0026] Figure 3 It is a schematic diagram of the fixed structure of the upper port of the secondary branch pipe.

[0027] Figure 4 This is an embodiment of the gas flow diagram of the underground reservoir and pipeline when the pipeline connection of the tunnel or goaf changes and the water level changes. (The wavy lines and arrows indicate the gas flow of the tunnel and each pipeline when the water level rises from 1 to 2, that is, the gas flow direction when the high pressure is balanced, and the straight lines and arrows indicate the gas flow of the tunnel and each pipeline when the water level drops from 2 to 1, that is, the gas flow direction when the negative pressure is eliminated.)

[0028] In the figure:

[0029] 001- goaf; 0201- main pipeline; 0202- primary branch pipeline; 003- pumping unit; 004- secondary branch pipe; 005- pad; 006- expansion bolt; 007- bolt; 010- connecting rod; 011- cone shield; 012- filter screen; 014- connecting piece. DETAILED DESCRIPTION

[0030] In order to make the objectives, technical solutions, methods and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0031] The high pressure and negative pressure in the present invention are compared with the atmospheric pressure, that is, higher than the atmospheric pressure is the high pressure and lower than the atmospheric pressure is the low pressure.

[0032] The invention discloses an air pressure balance and storage capacity monitoring device for underground reservoirs rebuilt from abandoned mines (see Figure 1 ) includes a main pipeline 0201 and various first-level branch pipelines 0202 and second-level branch pipes 004. The main pipeline is set in the ventilation lane or return air lane of the abandoned mine, and a first-level branch pipeline 0202 is set at each lane entrance. All first-level branch pipelines are connected to the main pipeline. The first-level branch pipelines are arranged along the lane. A number of second-level branch pipes 004 are set at different heights in the goafs passed by the lanes. The second-level branch pipes are connected to the corresponding first-level branch pipelines. The upper end pipe openings of the second-level branch pipes in the same goaf are installed at different heights to monitor and balance the air pressure at different heights in the goaf. The number of branch pipes is not necessarily the same, and they are arranged reasonably according to the storage capacity of the goaf. Secondary branch pipes must be set at the elevation position of the goaf near the roof; the number of main pipes can be multiple, which are responsible for the air pressure balance and storage capacity monitoring in the nearby tunnels and goafs; the upper end of the main pipe is connected to the external environment, and branch pipes are led out from the main pipe at the tunnel position. The main pipe 0201 goes deep into each tunnel entrance through the ventilation tunnel, and then each first-level branch pipe 0202 and second-level branch pipe are connected to each tunnel and goaf 001 that needs to balance the air pressure, and each goaf is connected together with the first-level branch pipe 0202 and the second-level branch pipe;

[0033] The upper port of each secondary branch pipe is located at an elevation where the water level needs to be monitored in the goaf, and the upper port of each secondary branch pipe is fixed to the roof of the goaf by connecting an anti-collision structure.

[0034] The connecting anti-collision structure includes a hard conical shield 011, a connecting rod 010 and a connecting piece 014. One end of the connecting rod is detachably fixed to the top plate of the goaf, and the other end is welded to the tip of the conical shield. The lower part of the conical shield is fixed to the upper port of the secondary branch pipe through the connecting piece, ensuring that the lower end surface of the conical shield can cover the upper port of the secondary branch pipe, and the upper port of the secondary branch pipe can communicate with the space in the goaf, ensuring that the secondary branch pipe will not be damaged by hard objects such as falling rocks, so as to play a role in regulating air pressure.

[0035] A filter 012 should be added to the ports of the main pipeline 0201 and the secondary branch pipe to filter out coarser impurities to prevent clogging of the pipeline. The filter 12 is made of fine iron wire. An anti-shielding structure is arranged above the main pipeline 0201 to ensure that when it is connected to the external environmental air pressure, it can prevent hard objects such as falling rocks from damaging the pipeline; the anti-shielding structure can also take the form of a conical shield and a connector. The connector connects the conical shield to the upper port of the main pipeline. The connector is a hollow frame that can ensure that the main pipeline is connected to the air.

[0036] The lowest point where the secondary branch pipe and the primary branch pipe meet is connected to the pumping unit 003 through a hose. At the same time, a pumping unit can be set at the intersection of the main pipe and the primary branch pipe according to actual needs, so that the accumulated water inside the pipe can be removed in time when needed. At the same time, a water immersion sensor is installed at the upper port of each secondary branch pipe to monitor the water level at different heights in the goaf. The water immersion sensor 014 and the pumping unit 003 are electrically connected to the controller 017 in the control room for data transmission control, and the staff can monitor and control the reservoir capacity in real time indoors. According to the storage capacity of the goaf and the elevation distribution in the goaf, secondary branch pipes with different elevations are set. It is also possible to set a secondary branch pipe for every 3cm height change, which is conducive to accurately monitoring the storage capacity change. A water immersion sensor is placed at the top of the secondary branch pipe to measure the elevation; the setting of secondary branch pipes at different heights can eliminate the negative pressure caused by the reduction of the water level.

[0037] The working principle is as follows: first, survey the abandoned mine, clarify the elevation of each point to be monitored and the number of air columns to be eliminated, record the number of the elevation point position in each goaf and tunnel that needs to balance the air pressure, and record the cross-sectional area at the elevation position of each point, and obtain the relationship between different elevations and the reservoir capacity of the monitored tunnel or goaf so as to obtain the current reservoir capacity of the mine from the elevation data. The main pipeline 0201 is connected to the outside atmosphere through the ventilation tunnel of the mine, and each first-level branch pipeline 0202 is connected to the main pipeline 0201 through a connecting component. The number of secondary branch pipes can be determined according to the number of air columns to be eliminated and the number of elevations of the monitored water level. The secondary branch pipes are connected to the highest point of the goaf 001 that needs to balance the air pressure and the elevation position of the water level that needs to be monitored through the tunnel. At the same time, in order to avoid the pipeline being too long, the branch pipes in the goaf and tunnel can be connected to the adjacent ventilation tunnel. The entire pipeline system (including the main pipeline, the primary branch pipeline, and the secondary branch pipe) has three functions: First, the goaf area that needs to balance the air pressure is connected to the outside air through the pipeline system to eliminate the air column generated by the water filling in the goaf. Second, after the abandoned mine is filled with water, the water will contact the water immersion sensor contacts from low to high through the upper port 004 of each secondary branch pipe, thereby activating the water immersion sensor, so that the actual water level of the reservoir can be understood and the storage capacity of the reservoir can be understood. Third, due to the existence of negative pressure, the flow of water out of the reservoir slows down. The setting of multiple secondary branch pipes of different heights in the goaf can eliminate the negative pressure caused by the drop in water level after pumping. Specifically: the upper port of the secondary branch pipe set at the top plate of the goaf can be connected to the ventilation tunnel or the outside world to balance the negative pressure. At the same time, the secondary branch pipe that was not submerged by water before precipitation can also balance the negative pressure.

[0038] like Figure 4As shown, the wavy lines and arrows indicate that when the water surface line rises from water surface line 1 to water surface line 2, the gas in the tunnel and goaf flows through the tunnel and various pipelines and is discharged to the outside, that is, the high pressure caused by the rising water level is balanced. Specifically, as the water surface line 1 gradually rises, the gas rises and first passes through the upper ports of all secondary branch pipes to connect with the outside world. The water surface line continues to rise, submerging the upper port of the lowest secondary branch pipe, and connecting with the outside world through the upper ports of the remaining secondary branch pipes. When the water surface line 2 below the upper port of the highest secondary branch pipe is reached, only the highest secondary branch pipe is connected to the outside world to discharge the gas in the goaf. The straight lines and arrows indicate that when the water surface line drops from water surface line 2 to water surface line 1, the outside air enters the tunnel and goaf from the tunnel and various pipelines to balance the negative pressure caused by the drop in water level. Since the water inside the pipeline is not completely removed after the mine is pumped, which affects the balance of air pressure in the goaf during the next water filling, a pumping unit 003 is installed at the intersection of each primary branch pipeline and the secondary branch pipe to further remove the accumulated water inside the pipeline system after the mine is pumped, thereby ensuring the smooth flow of the entire pipeline system and not affecting the use of the next water filling. Each water immersion sensor 014 and the pumping unit are connected to the controller 017 in the control room, and the technicians can observe and control the reservoir capacity in real time.

[0039] Example 1

[0040] Before installing the pipeline, it is necessary to detect the elevation of each tunnel and goaf, and mark all the elevations that need to be monitored. i And measure the area S of the cross section at each elevation i , which also includes the area of ​​the bottom of the tunnel and goaf. Through the geological survey data completed in advance, the elevation that needs to be monitored in the goaf or tunnel is obtained, and the two adjacent elevation points are recorded as h i 、h i-1 , i represents the elevation point number in the current goaf or tunnel, the bottom of the goaf is numbered 0, h 0 is 0, and is numbered 1, 2, ..., i-1, i, ..., n from bottom to top according to the height, where n is the number of water immersion sensors in the goaf or tunnel;

[0041] According to the formula Calculate the current reservoir capacity in the goaf or tunnel, m is the number of the highest water sensor triggered by the current water level, m is not greater than n; S i Refers to height h i The corresponding area, S i-1 Refers to height h i-1 The corresponding area is obtained through measurement in the early stage. During the survey, the approximate area is taken, that is, the irregular area of ​​each measuring point is approximated as a rectangle for calculation;

[0042] The tunnel refers to the passage excavated for ventilation and transportation during mining, and the goaf refers to the cavity left after mining. If the reservoir capacity of the tunnel is calculated, and the secondary branch pipes and corresponding water immersion sensors are arranged at different elevations in the tunnel, then S i is the current elevation of the roadway h i The cross-sectional area.

[0043] When water is injected, the water level gradually increases. During the process of water level increase, the water immersion sensor that is triggered first works to give the current elevation and corresponding number. The current reservoir capacity can be calculated through the above formula;

[0044] When water is released, since the water submerges most of the water immersion sensors, the submerged water immersion sensors work and the number of the water immersion sensor at the highest point triggered is recorded. The current reservoir capacity is calculated according to the above formula. When the water level gradually decreases, the water immersion sensor at the highest point currently triggered gradually stops working, and the reservoir capacity is calculated according to the number of the water immersion sensor at the next highest point.

[0045] The controller obtains the data and corresponding number of the water immersion sensor in real time. At the same time, the controller stores the area data of the cross section of the corresponding elevation of the corresponding goaf or tunnel. According to the formula It can calculate the current reservoir capacity of each goaf or tunnel to be monitored, and obtain the reservoir capacity of the current mine by summing up the current reservoir capacities of all monitored goafs or tunnels. It can also display the current working water immersion sensors of each goaf or tunnel and their corresponding numbers, the current reservoir capacity of each goaf or tunnel, and the reservoir capacity of the current mine on the display screen connected to the controller.

[0046] This embodiment is an air balance and storage capacity monitoring device for underground water reservoirs converted from abandoned mines. The main pipeline 0201 penetrates into each goaf or goaf that needs to balance air pressure through a tunnel or return air tunnel close to the primary branch pipeline and the secondary branch pipe, and then connects the primary branch pipeline 0202 at the intersection of the ventilation tunnel and the tunnel. If the tunnel needs to balance air pressure, the main pipeline leads multiple secondary branch pipes on the primary branch pipeline in the tunnel. The multiple secondary branch pipes are set at different heights to adjust the air pressure in the tunnel. If the goaf needs to balance air pressure, the secondary branch pipes are set at different heights in the goaf. The upper port of the secondary branch pipe must be set at the top elevation of the goaf. The main pipeline is connected to the secondary branch pipe through the primary branch pipe; the upper port of the secondary branch pipe connected to the goaf should be placed at the top of the goaf and at the elevation of each water level that needs to be monitored so that the air can be fully exhausted. When installing the secondary branch pipe for monitoring the mine storage capacity, the influence of the terrain should be fully considered to avoid the phenomenon of long pipes being suspended as much as possible to prevent the pipes from being damaged due to excessive dead weight.

[0047] like Figure 2When fixing the main pipeline and the first-level branch pipeline, use a double-hole pipe clamp (select a double-hole pipe clamp of corresponding size according to the diameter of the pipeline 008, clamp the pipeline 008 through the pad 005, and connect the double-hole pipe clamp to the mine floor through the expansion bolt 006). Fix it to the ground of the ventilation lane or tunnel with bolts 006 to prevent the pipeline from being displaced due to various disturbances. At the same time, fixing it to the ground can improve the bearing capacity of the pipeline and avoid the bolts from falling off due to the excessive mass of the pipeline and the water inside it, or the top plate is not solid and the bolts are not fixed firmly, which will cause the pipeline to be damaged. The second-level branch pipeline 004 is placed in the vertical direction, with one end connected to the first-level branch pipeline 0202 and the other end connected to the top plate. The pipe mouth of the first-level branch pipeline is along the direction of the tunnel, and the upper 005 does not need to be fixed.

[0048] like Figure 3 A filter 012 made of fine iron wire should be installed at the port of each branch pipe to prevent large impurities from entering and blocking the pipe. At the same time, a conical shield 011 is installed as a device to prevent rocks from falling from the roof, thereby preventing rocks from damaging the water pipe port. The conical shape can prevent the accumulation of heavy objects on the shield and reduce the bearing capacity of the roof. The conical shield is made of anti-corrosion metal plate. The conical shield is fixed to the secondary branch pipe through a metal connection 010. At the same time, the tip of the metal cone 011 is fixed to the roof through a connecting rod 010 and a bolt 006 to ensure that the bolts are firmly fixed to bear the weight of the pipe. The upper ports of all secondary branch pipes in the goaf are fixed to the roof of the goaf to keep the relative elevation position of the upper ports unchanged. The installation of different secondary branch pipes is adapted by changing the length of the connecting rod 010. The secondary branch pipe adopts a hose, which can adapt to the complex terrain in the goaf and has a low cost. The diameter and number of the secondary branch pipes can be selected according to the storage capacity of the goaf.

[0049] All metal parts, connecting rods, bolts and other metal products of double-hole pipe clamps in the mine must be treated with anti-corrosion to prevent water and air from corroding them and affecting their service life. The number of each first-level branch pipe 0202 and second-level branch pipe connected to the main pipeline 0201 should be determined according to the actual situation of the mine, the number of goafs 001 that need to balance the air pressure and the number of elevations to be monitored. The main pipeline and the first-level branch pipes with larger diameters can use PVC pipes, and the second-level branches with smaller flow and smaller diameter can use plastic hoses to reduce costs. The diameter of the main pipeline 0201 should be larger than that of the first-level branch pipe 0202. The specific pipe diameter should be determined by the actual volume of the goaf 001 that needs to balance the air pressure. To ensure that the connection between the main pipeline 0201 and the first-level branch pipe 0202 and the second-level branch pipe 0202 is firm and airtight, PVC pipes are often connected in the following two ways.

[0050] The first method: adhesive connection

[0051] Use a fine-tooth saw or cutter to cut the PVC drain pipe to the corresponding size. Use a hammer to remove the burrs and rough edges of the fracture, and chamfer them. Before applying the adhesive, use a dry cloth to wipe off the dust, water, and oil stains on the surface of the socket. Use a brush to evenly apply the adhesive on the surface of the socket. Find the center of the two pipes and the pipe, quickly insert the socket into the socket and turn it a quarter of a turn, and keep it still for at least 10 minutes to allow the adhesive to be evenly distributed and cured. Use a cloth to wipe off the excess adhesive on the outside of the coffin, and water can be passed 2 hours after the connection.

[0052] The second type: elastic rubber ring connection

[0053] Cut the pipe as required, and chamfer the socket end (15 to 20 degrees). The thickness of the groove end is one-third to one-half of the pipe wall. When cutting the pipe, ensure that the cut is flat and perpendicular to the pipe axis. After completing the cutting and beveling of the pipe end, clean the residue, make a trial connection, and mark the insertion length. The insertion length should leave about 5-10 mm for the socket of the pipe joint. Wipe the rubber ring in the socket and the working surface of the socket end with a rag, and put the cleaned rubber ring into the socket. Use a brush to evenly apply lubricant to the rubber ring at the socket and the outer surface of the socket end, lubricate V-type fatty acid salts (such as detergent), and do not use butter as a lubricant, because such substances often corrode the rubber ring. Align the socket of the connecting pipe with the socket, keep the insertion shutoff straight, and use a manual hoist or other pulling machine to insert the pipe to the mark at one time. If the insertion resistance is too large, do not force it in to prevent the rubber ring from twisting. Insert a feeler gauge along the socket gap and check along the circumference of the pipe to see if the rubber ring is installed normally.

[0054] After the abandoned mine is pumped, there will inevitably be water inside the pipeline system that cannot be completely drained. This water will hinder the air discharged through the pipeline during the next water filling. Therefore, a hose is installed at the lowest point of the pipeline system to connect the pumping unit. The function of the pumping unit is to discharge this water, so as to ensure that the air can be discharged freely during the next water filling process, and a water immersion sensor is installed at the port 004 of each pipe. Before construction, the elevations of the abandoned mine are measured and the elevations to be measured are marked, which is to monitor the water level. During construction, the corresponding pipeline port is installed at this height. When the monitoring water level is reached, the water will contact the contact of the water immersion sensor, thereby activating the water immersion sensor, and the storage capacity of the reservoir can be monitored. For example, when the water level reaches the water level to be monitored, such as 5 meters, the contact of the water immersion sensor placed at the pipeline port at this height encounters water to activate the sensor. After the controller obtains the corresponding activated water immersion sensor data, it can display the current water level and storage capacity in the control room after processing, so as to achieve the purpose of accurately controlling the filling and discharge volume. After the assembly of the various components of the system is completed, an air tightness check can be carried out to ensure that the entire pipeline system is firmly connected and airtight.

[0055] The present invention creatively integrates the functions of eliminating the high pressure of the underground reservoir when filling with water, eliminating the negative pressure generated during drainage, and monitoring the reservoir capacity, thereby simplifying the construction process and construction costs. At the same time, the cost of this application is mainly composed of pipelines, water pumps, and sensors. The specific number depends on the number of goaf areas that need to balance the air pressure, and pipes with smaller diameters use lower-cost plastic hoses. Therefore, the overall cost is more advantageous than other solutions.

[0056] The above is only an embodiment of the present invention, which is for the purpose of illustrating the purpose, technical solution and method of the present invention, but not to limit the scope of the present invention. Those skilled in the relevant field may improve the embodiments of the present invention according to the contents disclosed in the application documents without departing from the technical concept and scope of the present invention.

[0057] Any matters not described in the present invention are applicable to the prior art.

Claims

1. An abandoned mine converted underground reservoir pressure balance and storage capacity monitoring device, used to balance the atmospheric pressure of each tunnel and goaf with the external environment, and monitor the storage capacity. It is characterized in that The device comprises a main pipeline and various primary branch pipelines and secondary branch pipes. The main pipeline is arranged at the ventilation lane or return air lane of the abandoned mine, and a primary branch pipeline is arranged at each lane entrance. All primary branch pipelines are connected to the main pipeline. The primary branch pipeline is arranged along the lane. A number of secondary branch pipes are arranged at different heights in the goaf and / or lanes through which the lane passes. The secondary branch pipes are connected to the corresponding primary branch pipelines. The upper end pipe openings of the secondary branch pipes in the same goaf or the same lane are installed at different heights for monitoring and To balance the air pressure at different heights in goafs or tunnels, the number of secondary branch pipes in each goaf is not necessarily the same. They are arranged according to the storage capacity of the goaf. Secondary branch pipes must be set at the elevation of the goaf near the roof; the upper end of the main pipeline is connected to the external environment, and branch pipes are led out from the main pipeline at the tunnel position. The main pipeline goes deep into each tunnel entrance through the ventilation tunnel, and then each first-level branch pipe and second-level branch pipe are connected to each tunnel and goaf that needs to balance the air pressure. The tunnel and each goaf are connected together with the first-level branch pipe and the second-level branch pipe; The upper end of each secondary branch pipe is located at an elevation position in the goaf or tunnel where the water level needs to be monitored, and the upper end of each secondary branch pipe is fixed to the roof of the goaf or tunnel by connecting the anti-collision structure; The lowest point where the secondary branch pipe meets the primary branch pipe is connected to the pumping unit through a hose. At the same time, a water immersion sensor is installed at the upper port of each secondary branch pipe to monitor the water level at different heights in the goaf; the water immersion sensor and the pumping unit are electrically connected to the controller in the control room.

2. The device for monitoring the pressure balance and storage capacity of underground reservoirs converted from abandoned mines according to claim 1, It is characterized in that The connecting anti-collision structure includes a hard conical shield, a connecting rod and a connecting piece. One end of the connecting rod is detachably fixed to the top plate of the goaf or tunnel, and the other end is welded to the tip of the conical shield. The lower part of the conical shield is fixed to the upper port of the secondary branch pipe through the connecting piece to ensure that the lower end surface of the conical shield can cover the upper port of the secondary branch pipe, and the upper port of the secondary branch pipe can communicate with the space in the goaf or tunnel.

3. The device for monitoring the pressure balance and storage capacity of underground reservoirs converted from abandoned mines according to claim 1, It is characterized in that There are multiple main pipelines, which are responsible for air pressure balance and storage capacity monitoring in the tunnels and goafs nearby. At the same time, pumping units are set at the intersection of the main pipeline and the first-level branch pipeline according to actual needs; filters are set at the ports of the main pipeline and the second-level branch pipe to prevent pipe blockage. The filter is made of fine iron wire material, and an anti-shielding structure is set above the main pipeline to ensure that when it is connected to the external environmental air pressure, it can prevent hard objects from damaging the pipeline.

4. The device for monitoring the pressure balance and storage capacity of underground reservoirs converted from abandoned mines according to claim 1, It is characterized in that The working principle of the device is as follows: first, the abandoned mine is surveyed, the elevation of each point to be monitored is determined, the number of the elevation point position in each goaf and tunnel is recorded, and the cross-sectional area at the elevation position of each point is recorded, and the relationship between different elevations and capacities is obtained so as to obtain the current volume of the mine from the elevation data; Connect the secondary branch pipe through the tunnel to the highest point of the goaf or tunnel where the gas pressure needs to be balanced and the elevation position of the water level that needs to be monitored; The entire pipeline system including the main pipeline, the first-level branch pipeline and the second-level branch pipeline has three functions: first, the goaf where the air pressure needs to be balanced is connected to the outside air through the pipeline system, thereby eliminating the air column generated by the water filling in the goaf; second, after the abandoned mine is filled with water, the water will contact the water immersion sensor contacts from low to high through the upper ports of each second-level branch pipe, thereby activating the water immersion sensor, obtaining the actual water level line of the reservoir and thus the storage capacity of the reservoir; third, due to the existence of negative pressure, the flow of water out of the reservoir is slowed down. The setting of multiple second-level branch pipes of different heights in the goaf can eliminate the negative pressure caused by the drop in water level after pumping. Specifically: the upper port of the second-level branch pipe arranged at the top plate of the goaf can be connected to the ventilation tunnel or the outside world to balance the negative pressure. At the same time, the second-level branch pipe that was not submerged by water before precipitation can also balance the negative pressure.

5. The device for monitoring the pressure balance and storage capacity of underground reservoirs converted from abandoned mines according to claim 1, It is characterized in that According to the storage capacity of the goaf and the elevation distribution in the goaf, set up secondary branch pipes with different elevations; or set up a secondary branch pipe every 3cm height change, and place a water immersion sensor at the top of the secondary branch pipe.

6. A method for monitoring the pressure balance and storage capacity of underground reservoirs rebuilt from abandoned mines. It is characterized in that The monitoring method uses the monitoring device described in any one of claims 1 to 5, and the specific steps of the method are: Before installing the pipeline, it is necessary to detect the elevation of each tunnel and goaf, and mark all the elevations that need to be monitored. i And measure the area S of the cross section at each elevation i , which also includes the area of ​​the bottom of the tunnel and goaf; through the geological survey data completed in advance, the elevation that needs to be monitored in the goaf or tunnel is obtained, and the two adjacent elevation points are recorded as h i 、h i-1 , i represents the elevation point number in the current goaf or tunnel, the bottom of the goaf is numbered 0, h 0 is 0, and is numbered 1, 2, ..., i-1, i, ..., n from bottom to top according to the height, where n is the number of water immersion sensors in the goaf or tunnel; The controller obtains the data and corresponding number of the water immersion sensor in real time. At the same time, the controller stores the area data of the cross section of the corresponding elevation of the corresponding goaf or tunnel. According to the formula It can calculate the current reservoir capacity of each goaf or tunnel to be monitored, and obtain the reservoir capacity of the current mine by summing the current reservoir capacities of all monitored goaf or tunnels, and display the current working water immersion sensors of each goaf or tunnel and the corresponding numbers, the current reservoir capacity of each goaf or tunnel, and the reservoir capacity of the current mine on the display screen connected to the controller; Where V m is the current reservoir capacity in the goaf or tunnel, m is the number of the water sensor at the highest point triggered by the current water level, and m is not greater than n; When water is injected, the water level gradually increases. During the process of water level increase, the water immersion sensor that is triggered first works to give the current elevation and corresponding number. The current reservoir capacity can be calculated through the above formula; As the water surface gradually rises, the gas first passes through the upper ports of all the secondary branch pipes and connects to the outside world. The water surface continues to rise, submerging the upper port of the lowest secondary branch pipe, and connecting to the outside world through the upper ports of the remaining secondary branch pipes. When the water surface reaches the lower part of the upper port of the highest secondary branch pipe, only the highest secondary branch pipe is connected to the outside world, discharging the gas in the goaf and achieving the effect of balancing the gas pressure. When water is released, since most of the water sensors are submerged, the submerged water sensors work, and the number of the water sensor at the highest point triggered is recorded. The current reservoir capacity is calculated according to the above formula. When the water level gradually decreases, the water sensor at the highest point currently triggered gradually stops working, and the reservoir capacity is calculated according to the number of the water sensor at the next highest point. When the water surface line at the bottom of the upper port of the highest secondary branch pipe drops to the initial water surface line, outside air enters the tunnel and goaf from the tunnel and pipelines to balance the negative pressure caused by the drop in water level. The pumping units installed at the intersection of each primary branch pipe and the secondary branch pipe further remove the accumulated water inside the pipeline system after the mine is pumped out, so as not to affect the balance of air pressure in the goaf during the next water filling.

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