Integrated system for monitoring discharge of fissure water in surrounding rock of underground gas storage and leakage of compressed air

Abstract

The application discloses an integrated system for discharging surrounding rock fissure water and monitoring compressed air leakage of an underground gas storage. The system comprises a surrounding rock fissure water discharge system and a compressed air leakage monitoring system. The surrounding rock fissure water discharge system comprises a circumferential drainage pipe and a longitudinal drainage pipe attached to the surface of the surrounding rock wall of the gas storage. The circumferential drainage pipe is a plurality of flower pipes arranged axially and laid along the periphery of the gas storage. The longitudinal drainage pipe is two flower pipes laid along the two sides of the bottom of the gas storage and extending axially to the outside of the gas storage. A valve and a drainage pump are connected to the outside of the longitudinal drainage pipe. The compressed air leakage monitoring system comprises an optical fiber sensor laid in the circumferential drainage pipe and the longitudinal drainage pipe. The optical fiber sensor is connected to an information access collecting unit on the ground. The system can not only monitor the compressed air in the gas storage in real time and locate the leakage, but also discharge the surrounding rock fissure water outside the gas storage in time.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of artificial hard rock underground gas storage, in particular to an integrated system for monitoring leakage of compressed air and discharge of fissure water in surrounding rock of an underground gas storage. BACKGROUND

[0002] Compressed air energy storage is a technology that uses compressed air as a medium to store excess electricity. During the off-peak period, it uses excess electricity from wind power and the power grid to drive the air compressor to convert electricity into the internal energy of compressed air and store it in the underground chamber. During the peak period, the high-pressure air is released to convert the potential energy of compressed air into mechanical work of the expander to drive the generator to generate electricity.

[0003] The compressed air energy storage power station is currently mainly divided into ground structures and underground structures. Due to economic and safety considerations, underground gas storage facilities have become the mainstream. Artificially excavated underground sealed caverns are one of the underground gas storage facilities, which have the advantages of flexible site selection, low cost, safety and reliability. The structural type of such underground sealed caverns mainly includes silo type and tunnel type. The tunnel type has become the current main technical scheme due to its low construction difficulty and safety and reliability.

[0004] The tunnel wall structure of the underground gas storage includes, from inside to outside, a steel lining sealing layer, a concrete lining layer and surrounding rock. The main function of the steel lining sealing layer is to seal the compressed air, the concrete lining layer is used to smooth the excavated rock surface to provide a smooth foundation for the steel lining, and the surrounding rock bears the internal high pressure generated by the compressed air.

[0005] During the operation of the power station, under the long-term action of the cyclically changing internal high pressure, the concrete lining layer will inevitably produce through cracks, the surrounding rock may produce plastic shear failure, and the steel lining sealing layer may also have local damage. These conditions are likely to cause gas leakage in the gas storage, which will affect the operation efficiency of the power station and need to be repaired in time.

[0006] During the maintenance of the power station, the internal air pressure will be released. If the fissure water in the surrounding rock is not emptied, the underground fissure water in the surrounding rock will pass through the concrete cracks, and the concrete lining layer and the sealing steel lining layer will bear high water pressure, thereby causing instability of the concrete lining and buckling damage of the steel lining.

[0007] Therefore, real-time monitoring of compressed air leakage in the underground gas storage, real-time positioning of the leakage position, and how to ensure the safety of the sealing layer during maintenance are of great significance to the safe and efficient operation of the gas storage. However, there is no mature and reliable technical solution at home and abroad at present. SUMMARY

[0008] In view of the shortcomings of the prior art, the underground gas storage surrounding rock fissure water discharge and compressed air leakage monitoring integrated system can not only monitor the compressed air in the gas storage in real time and locate the leakage position in real time during normal operation of the gas storage, but also can discharge the surrounding rock fissure water outside the gas storage in time before the gas storage is overhauled, so as to avoid the damage of water pressure to the concrete lining layer and the sealing layer during the overhaul.

[0009] To achieve the above-mentioned purpose, the underground gas storage surrounding rock fissure water discharge and compressed air leakage monitoring integrated system is designed for discharging the surrounding rock fissure water outside the tunnel type underground gas storage and monitoring the leakage of the compressed air in the tunnel type underground gas storage, and has the following special features: the system comprises a surrounding rock fissure water discharge system and a compressed air leakage monitoring system.

[0010] The surrounding rock fissure water discharge system comprises a perforated drainage pipe attached to the surface of the surrounding rock wall of the gas storage, the perforated drainage pipe comprises a circumferential drainage pipe and a longitudinal drainage pipe which are in communication with each other, the circumferential drainage pipe is a plurality of flower pipes which are arranged in an axial direction and laid along the periphery of the gas storage, and the longitudinal drainage pipe is two flower pipes which are laid along the two sides of the bottom of the gas storage and extend to the outside of the gas storage in an axial direction, so that the surrounding rock fissure water seeps into the circumferential drainage pipe and then flows into the longitudinal drainage pipe.

[0011] The longitudinal drainage pipe located outside the gas storage is connected with a valve, and the outlet of the valve is connected with a drainage pump; before the gas storage is overhauled, the valve and the drainage pump are opened, the surrounding rock fissure water collected is discharged to the outside of the gas storage by the drainage pump, and the water level of the surrounding rock fissure water is lowered to the bottom of the gas storage, so that the concrete lining layer and the sealing layer of the gas storage are not damaged; when the gas storage is normally used for storing gas, the valve and the drainage pump are closed, the surrounding rock fissure water enters the circumferential drainage pipe and the longitudinal drainage pipe through the openings in the flower pipes, the circumferential drainage pipe and the longitudinal drainage pipe are full of water, and the periphery of the gas storage is soaked in the surrounding rock fissure water.

[0012] The compressed air leakage monitoring system comprises an optical fiber sensor laid in the circumferential drainage pipe and the longitudinal drainage pipe, the optical fiber sensor is used for monitoring the change of water pressure at the corresponding position in the pipe, the optical fiber sensor is connected with an information access acquisition unit located on the ground, the information access acquisition unit is used for receiving, processing and judging the pressure signal, when gas leakage occurs at a certain position of the gas storage, the high-pressure leakage gas will cause the water pressure in the circumferential drainage pipe or the longitudinal drainage pipe at the corresponding position to change dramatically, the information access acquisition unit can timely judge the leakage position of the high-pressure gas and issue a compressed gas leakage warning.

[0013] Further, the installation steps of the surrounding rock fissure water discharge system and the compressed air leakage monitoring system are as follows:

[0014] S1) tunnel type underground gas storage surrounding rock excavation;

[0015] S2) in the surrounding rock surface shotcrete permeable concrete;

[0016] S3) in the permeable concrete surface laid annular drain pipe and longitudinal drain pipe, and with the valve and drainage pump outside the gas storage connected;In the annular drain pipe and longitudinal drain pipe pipe laid optical fiber sensor, the optical fiber sensor is connected to the information access acquisition unit on the ground;

[0017] S4) in the perforated drain pipe surface concrete lining layer construction;

[0018] S5) in the concrete lining layer surface sealing layer construction.

[0019] Further, in S3), the annular drain pipe and longitudinal drain pipe need to pass through the horizontal or vertical cracks in the surrounding rock of the gas storage.

[0020] Further, in S3), the spacing between adjacent annular drain pipes is determined according to the surrounding rock crack, which is 2-3m.

[0021] Further, in S3), the optical fiber sensor is a passive optical fiber, which uses the reflection or refraction change of the optical signal itself in the transmission process to identify the pressure, resist electromagnetic interference, and resist high temperature and corrosion.

[0022] Further, the inner diameter of the tunnel type underground gas storage is 10-18m, and the surrounding rock of the gas storage can bear 6-30Mpa high pressure cyclic load.

[0023] The advantages of the present application are:

[0024] 1, the design scheme of the present application considers the operation and maintenance of the gas storage, so that in the operation stage, the compressed air in the gas storage can be monitored in real time, and the leakage position can be located in real time;In the maintenance stage, the surrounding rock fissure water outside the gas storage can be discharged in time, so as to avoid the damage of water pressure to the concrete lining layer and the sealing layer;Thus, the operation and maintenance of the gas storage are guaranteed;

[0025] 2, the present application is arranged on the surface of the surrounding rock wall of the gas storage, and the valve and drainage pump are arranged at the longitudinal drain pipe outside the gas storage, before the maintenance of the gas storage, the collected surrounding rock fissure water is discharged to the outside of the gas storage by the drainage pump, until the surrounding rock fissure water is reduced to the bottom of the gas storage, which will not cause harm to the concrete lining layer and the sealing layer of the gas storage, so as to ensure the structural safety of the gas storage, improve the safety and stability of the gas storage operation, and improve the long-term operation ability;

[0026] 3、The application arranges the optical fiber sensor inside the perforated drainage pipe laid on the periphery of the gas storage, and the optical fiber sensor is connected with the information access collecting unit on the ground; during the normal operation of the gas storage, when the gas leakage phenomenon occurs at a certain position of the gas storage, the high-pressure leakage gas will cause the water pressure in the perforated drainage pipe at the corresponding position to change dramatically, the optical fiber sensor monitors the water pressure change at the corresponding position in the pipe, the information access collecting unit receives, processes and judges the pressure signal, judges the leakage position of the high-pressure gas in time, and sends the compressed gas leakage warning, which helps to repair in time and effectively, reduces the loss caused by leakage, and greatly improves the operation safety and efficiency of the power station;

[0027] The surrounding rock fissure water discharge and compressed air leakage monitoring integrated system of the underground gas storage of the application can not only monitor the compressed air in the gas storage in real time and locate the leakage position in real time during the normal operation of the gas storage, but also can discharge the surrounding rock fissure water outside the gas storage in time before the maintenance of the gas storage, so as to avoid the damage of water pressure to the concrete lining layer and the sealing layer during the maintenance. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The structure composition diagram of the application;

[0029] Figure 2 The three-dimensional schematic view of the application;

[0030] Figure 3 The transverse sectional view of the perforated drainage pipe in the application;

[0031] In the figure: surrounding rock fissure water discharge system 1, compressed air leakage monitoring system 2;

[0032] The surrounding rock fissure water discharge system 1 comprises: a perforated drainage pipe 1-1, a valve 1-2 and a drainage pump 1-3.

[0033] The perforated drainage pipe 1-1 comprises: a ring-shaped drainage pipe 1-11 and a longitudinal drainage pipe 1-12.

[0034] The compressed air leakage monitoring system 2 comprises: an optical fiber sensor 2-1 and an information access collecting unit 2-2. DETAILED DESCRIPTION

[0035] The application will be further described in detail in combination with the drawings and specific embodiments.

[0036] In the description of the present application, it should be understood that the terms "length", "width", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application.

[0037] As shown in Figure 1 The integrated system for monitoring the fissure water discharge of surrounding rock and the leakage of compressed air of the underground gas storage of the present application, for discharging the fissure water of the surrounding rock outside the tunnel-type underground gas storage and monitoring the leakage of compressed air inside the tunnel-type underground gas storage, comprises a fissure water discharge system 1 of surrounding rock and a compressed air leakage monitoring system 2.

[0038] Specifically, the inner diameter of the tunnel-type underground gas storage is 10-18 m, and the surrounding rock of the gas storage can bear a high-pressure cyclic load of 6-30 MPa.

[0039] The fissure water discharge system 1 of surrounding rock comprises a perforated drainage pipe 1-1 attached to the surface of the rock wall of the surrounding rock of the gas storage, which comprises a circumferential drainage pipe 1-11 and a longitudinal drainage pipe 1-12 that are in communication with each other, the circumferential drainage pipe 1-11 is a plurality of flower pipes arranged axially and laid along the outer periphery of the gas storage, and the longitudinal drainage pipe 1-12 is two flower pipes laid along the two sides of the bottom of the gas storage and extending axially to the outside of the gas storage, so that the fissure water of the surrounding rock seeps into the circumferential drainage pipe 1-11 and then flows into the longitudinal drainage pipe 1-12.

[0040] The longitudinal drainage pipe 1-12 located outside the gas storage is connected with a valve 1-2, and the outlet of the valve 1-2 is connected with a drainage pump 1-3; before the maintenance of the gas storage, the valve 1-2 and the drainage pump 1-3 are opened, the accumulated fissure water of the surrounding rock is discharged to the outside of the gas storage by the drainage pump 1-3, until the water level of the fissure water of the surrounding rock is lowered to the bottom of the gas storage, which will not cause harm to the concrete lining layer and the sealing layer of the gas storage; when the gas storage is normally storing gas, the valve 1-2 and the drainage pump 1-3 are closed, the fissure water of the surrounding rock enters the circumferential drainage pipe 1-11 and the longitudinal drainage pipe 1-12 through the openings on the flower pipes, and the circumferential drainage pipe 1-11 and the longitudinal drainage pipe 1-12 are full of water, and the outer periphery of the gas storage is soaked in the fissure water of the surrounding rock, as shown in Figure 2 .

[0041] Under normal gas storage conditions, the valve 1-2 and the drainage pump 1-3 are closed to ensure the isolation of the fissure water of the surrounding rock from the external environment, so as to ensure that the perforated drainage pipe 1-1 is full of water. From the perspective of corrosion prevention, maintaining a full water state can avoid introducing oxygen near the sealed steel lining, which is beneficial to the corrosion prevention of the steel lining.

[0042] Specifically, the annular drainage pipe 1-11 and the longitudinal drainage pipe 1-12 can be perforated steel pipes or perforated PVC pipes, etc. The annular drainage pipe 1-11 is arranged annularly along the tunnel type gas storage, and then flows into the longitudinal drainage pipe 1-12 arranged at the bottom of the gas storage, and the longitudinal drainage pipe 1-12 is connected with the drainage pump 1-3 arranged outside the gas storage.

[0043] The present application can ensure the structural safety of the gas storage, and improve the safety and stability and long-term operation capacity of the gas storage in operation by laying the perforated drainage pipe 1-1 on the surface of the surrounding rock wall of the gas storage, arranging the valve 1-2 and the drainage pump 1-3 at the longitudinal drainage pipe 1-12 outside the gas storage, and discharging the collected fissure water of the surrounding rock to the outside of the gas storage by the drainage pump 1-3 before the maintenance of the gas storage, so that the concrete lining layer and the sealing layer of the gas storage are not damaged.

[0044] The compressed air leakage monitoring system 2 comprises an optical fiber sensor 2-1 laid in the annular drainage pipe 1-11 and the longitudinal drainage pipe 1-12, the optical fiber sensor 2-1 is used for monitoring the water pressure change at the corresponding position in the pipe, and the optical fiber sensor 2-1 is connected with an information access collection unit 2-2 on the ground, the information access collection unit 2-2 is used for receiving, processing and judging the pressure signal, when the gas leakage phenomenon occurs at a certain position of the gas storage, the high-pressure leakage gas will cause the water pressure in the annular drainage pipe 1-11 or the longitudinal drainage pipe 1-12 at the corresponding position to change sharply, the information access collection unit 2-2 can timely judge the leakage position of the high-pressure gas, and issue a compressed gas leakage warning, such as Figure 3 .

[0045] The compressed air leakage monitoring system 2 can timely judge the leakage position of the high-pressure gas, and issue a compressed gas leakage warning, which is helpful for timely and effective maintenance, reduces the loss caused by leakage, and greatly improves the operation safety and efficiency of the power station.

[0046] Specifically, the installation steps of the surrounding rock fissure water drainage system 1 and the compressed air leakage monitoring system 2 are as follows:

[0047] S1) excavate the surrounding rock of the tunnel type underground gas storage.

[0048] S2) spray the permeable concrete on the surface of the surrounding rock.

[0049] S3) laying the circumferential drainage pipe 1-11 and the longitudinal drainage pipe 1-12 on the surface of the pervious concrete, and connecting the circumferential drainage pipe 1-11 and the longitudinal drainage pipe 1-12 with the valve 1-2 and the drainage pump 1-3 outside the gas storage, and laying the optical fiber sensor 2-1 in the circumferential drainage pipe 1-11 and the longitudinal drainage pipe 1-12, and connecting the optical fiber sensor 2-1 with the information access and collection unit 2-2 on the ground.

[0050] Preferably, the circumferential drainage pipe 1-11 and the longitudinal drainage pipe 1-12 need to pass through the horizontal or vertical cracks in the surrounding rock of the gas storage.

[0051] Specifically, the spacing between adjacent circumferential drainage pipes 1-11 is determined according to the crack condition of the surrounding rock, and is generally 2-3 m.

[0052] Specifically, the optical fiber sensor 2-1 is a passive optical fiber, which uses the reflection or refraction change of the optical signal itself to identify the pressure in the transmission process, and is resistant to electromagnetic interference, high temperature and corrosion. The passive optical fiber is an optical fiber that does not need to be equipped with electronic devices to amplify the signal, and does not contain any electronic devices and electronic power supply.

[0053] S4) performing concrete lining layer construction on the surface of the perforated drainage pipe 1-1.

[0054] S5) performing sealing layer construction on the surface of the concrete lining layer.

[0055] The design scheme of the present application considers the operation and maintenance stages of the gas storage, so that in the operation stage, the compressed air in the gas storage can be monitored in real time, and the leakage position can be located in real time; in the maintenance stage, the fissure water of the surrounding rock outside the gas storage can be discharged in time to avoid damage to the concrete lining layer and the sealing layer caused by water pressure; thereby ensuring the operation and maintenance work of the gas storage.

[0056] The surrounding rock fissure water discharge and compressed air leakage monitoring integrated system of the underground gas storage of the present application not only can monitor the compressed air in the gas storage in real time and locate the leakage position in real time during the normal operation of the gas storage, but also can discharge the fissure water of the surrounding rock outside the gas storage in time before the maintenance of the gas storage to avoid damage to the concrete lining layer and the sealing layer caused by water pressure during the maintenance.

[0057] The above embodiments are the preferred embodiments of the present application, but the embodiments of the present application are not limited by the above embodiments, and any changes, modifications, substitutions, combinations and simplifications made without departing from the spirit and principles of the present application should be equivalent replacement methods, and are all included in the protection scope of the present application.

Claims

1. An integrated system for monitoring and discharging fissure water in the surrounding rock and monitoring compressed air leakage in an underground gas storage facility, used for discharging fissure water in the surrounding rock around a tunnel-type underground gas storage facility and monitoring compressed air leakage inside the tunnel-type underground gas storage facility, characterized in that: Includes a surrounding rock fissure water drainage system (1) and a compressed air leakage monitoring system (2); The surrounding rock fissure water drainage system (1) includes a perforated drainage pipe (1-1) attached to the surface of the surrounding rock wall of the gas storage tank. The perforated drainage pipe (1-1) includes a circumferential drainage pipe (1-11) and a longitudinal drainage pipe (1-12) that are interconnected. The circumferential drainage pipe (1-11) is a number of perforated pipes laid along the outer periphery of the gas storage tank and arranged at axial intervals. The longitudinal drainage pipe (1-12) is two perforated pipes laid along both sides of the bottom of the gas storage tank and extending axially to the outside of the gas storage tank. This allows the surrounding rock fissure water to seep into the circumferential drainage pipe (1-11) and then flow into the longitudinal drainage pipe (1-12). The longitudinal drainage pipe (1-12) located outside the gas storage is connected to a valve (1-2), and the outlet of the valve (1-2) is connected to a drainage pump (1-3). Before the gas storage is overhauled, the valve (1-2) and the drainage pump (1-3) are opened, and the collected rock fissure water is discharged outside the gas storage through the drainage pump (1-3) until the water level in the rock fissures drops to the bottom of the gas storage, which will not cause damage to the concrete lining and sealing layer of the gas storage. When the gas storage is storing gas normally, the valve (1-2) and the drainage pump (1-3) are closed, and the rock fissure water enters the circumferential drainage pipe (1-11) and the longitudinal drainage pipe (1-12) through the opening on the perforated pipe. The circumferential drainage pipe (1-11) and the longitudinal drainage pipe (1-12) are full of water, and the outer periphery of the gas storage is immersed in the rock fissure water. The compressed air leakage monitoring system (2) includes an optical fiber sensor (2-1) installed in the circumferential drain pipe (1-11) and the longitudinal drain pipe (1-12). The optical fiber sensor (2-1) is used to monitor the water pressure change at the corresponding location in the pipe. The optical fiber sensor (2-1) is connected to an information access acquisition unit (2-2) located on the ground. The information access acquisition unit (2-2) is used to receive, process, and judge the pressure signal. When a gas leak occurs at a certain location in the gas storage tank, the high-pressure leaked gas will cause a drastic change in the water pressure in the circumferential drain pipe (1-11) or the longitudinal drain pipe (1-12) at the corresponding location. The information access acquisition unit (2-2) promptly judges the location of the high-pressure gas leak and issues a compressed gas leak warning.

2. The integrated system for monitoring surrounding rock fissure water discharge and compressed air leakage in underground gas storage facilities according to claim 1, characterized in that: The installation steps for the surrounding rock fissure water drainage system (1) and the compressed air leakage monitoring system (2) are as follows: S1) Excavation of the surrounding rock for a tunnel-type underground gas storage facility; S2) Spraying permeable concrete onto the surface of the surrounding rock; S3) Lay circumferential drainage pipes (1-11) and longitudinal drainage pipes (1-12) on the permeable concrete surface and connect them to valves (1-2) and drainage pumps (1-3) outside the gas storage facility; lay fiber optic sensors (2-1) inside the circumferential drainage pipes (1-11) and longitudinal drainage pipes (1-12) and connect the fiber optic sensors (2-1) to the information access and acquisition unit (2-2) on the ground; S4) Concrete lining layer construction is carried out on the surface of the perforated drainage pipe (1-1); S5) Apply a sealing layer to the surface of the concrete lining layer.

3. The integrated system for monitoring surrounding rock fissure water discharge and compressed air leakage in underground gas storage facilities according to claim 2, characterized in that: In S3), the circumferential drainage pipe (1-11) and the longitudinal drainage pipe (1-12) need to pass through horizontal or vertical cracks in the surrounding rock of the gas storage tank.

4. The integrated system for monitoring surrounding rock fissure water discharge and compressed air leakage in underground gas storage facilities according to claim 3, characterized in that: In S3), the spacing between adjacent circumferential drainage pipes (1-11) is determined according to the surrounding rock fissures and is 2-3m.

5. The integrated system for monitoring surrounding rock fissure water discharge and compressed air leakage in an underground gas storage facility according to claim 4, characterized in that: In S3), the fiber optic sensor (2-1) is a passive fiber optic cable. During transmission, it uses the reflection or refraction of the light signal itself to identify pressure. It is resistant to electromagnetic interference, high temperature, and corrosion.

6. The integrated system for monitoring surrounding rock fissure water discharge and compressed air leakage in an underground gas storage facility according to claim 1, characterized in that: The inner diameter of the tunnel-type underground gas storage facility is 10-18m, and the surrounding rock of the gas storage facility can withstand a high-pressure cyclic load of 6-30MPa.

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