An underground water diversion barrel-shaped water-sealed oil storage cavern structure and construction method

Abstract

The application provides a kind of underground water diversion type barrel-shaped water seal oil storage structure and construction method, the oil storage structure is arranged in mountain with good hard integrity, no groundwater or unstable groundwater source and close to water source, including construction tunnel, oil storage group, barrel-shaped water seal system, water diversion system, drainage system, oil transportation system and monitoring system.The construction tunnel bottom plate is lower than the oil storage group bottom plate, the vertical impermeable curtain and horizontal impermeable curtain of barrel-shaped water seal system are barrel-shaped, which places the storage group in it, the water diversion system supplies water to the water curtain hole from the surface water source to the storage area by gravity, the drainage system drains the excess water in the water cushion layer to the surface by gravity, and the oil transportation system inputs oil from the surface to the storage and outputs oil from the storage to the surface by gravity.The application greatly reduces the amount of storage curtain, the water diversion type barrel-shaped water seal makes the water seepage of the storage controllable, the gravity drainage and oil transportation reduce the operation cost, and expand the use range of the underground water seal oil storage.

Description

Technical Field

[0001] This invention belongs to the field of petroleum storage engineering and relates to underground water-sealed oil cavern technology, specifically an underground water-diversion barrel-shaped water-sealed oil cavern structure and construction method. Background Technology

[0002] Currently, underground water-sealed oil and gas storage projects generally involve excavating caverns within well-preserved underground rock strata. Utilizing the non-mixing property of water and oil, the leakage of oil and gas is suppressed by ensuring that the infiltration pressure of groundwater into the storage cavern is greater than the outflow pressure of the oil and gas within the cavern, thereby achieving the storage purpose.

[0003] Water-sealed oil and gas caverns are typically built within deep, well-maintained rock formations with stable groundwater. Relying on natural groundwater and the permeability of the rock mass generally provides adequate hydraulic sealing. However, most rock masses have high permeability coefficients. To ensure the cavern's seepage rate meets design and specification requirements, seepage prevention treatment is usually required for the sidewalls and vaults of each cavern, resulting in a massive amount of seepage prevention curtain grouting work. In my country, the vast majority of existing oil and gas caverns have significantly excessive seepage rates, necessitating large-scale pumping from the cavern's water cushion layer to the surface after operation, thus substantially increasing operating costs. Summary of the Invention

[0004] To address the shortcomings of the above-mentioned problems, this invention provides an underground water-sealed barrel-shaped oil cavern structure and construction method. This invention eliminates the need for each cavern to install a seepage prevention curtain, which can significantly reduce the amount of seepage prevention curtain work and construction costs. Moreover, it is convenient to construct, can improve the construction progress, and makes the cavern seepage controllable and reduces the amount of sewage.

[0005] To achieve the above-mentioned technical objectives, this invention provides an underground water-diversion barrel-shaped water-sealed oil cavern structure. The oil cavern structure is located within a mountain near a stable water source, where there is no groundwater or the groundwater source is unstable. It includes a construction tunnel, an oil cavern group, a barrel-shaped water-sealed structure, a water diversion system, a drainage system, and an oil transportation system. The construction tunnel extends from the side of the mountain into the mountain and connects to the oil cavern group located within the mountain. The oil cavern group includes multiple oil caverns arranged side-by-side. Each oil cavern is constructed using a construction tunnel. Each oil cavern has a seepage-proof bottom slab. The bottom slab of the construction tunnel is lower than the seepage-proof bottom slab of each oil cavern. After the oil cavern construction is completed, the port connecting each oil cavern to the construction tunnel is sealed using a first sealing plug.

[0006] The barrel-shaped water seal structure includes a vertical grouting curtain and a horizontal grouting curtain. The vertical grouting curtain is installed around the oil cavern group, with its bottom surface lower than the bottom surface of the seepage-proof bottom plate of the oil cavern and its top surface higher than the highest part of the oil cavern. The horizontal grouting curtain is set between two adjacent oil caverns. The horizontal grouting curtain is connected to the seepage-proof bottom plate of each oil cavern to form an integral seepage-proof surface, and together with the vertical grouting curtain, it forms a cylindrical seepage-proof structure that covers the sides and bottom of the oil cavern group.

[0007] The water diversion system includes a water diversion tunnel connected to a stable water source, multiple water curtain tunnels and water curtain holes installed on the top surface of the oil cavern complex. The water curtain tunnels are horizontally arranged between the vertical grouting curtains and are interconnected with the water diversion tunnel. The water curtain holes are constructed from the water curtain tunnels along the extension direction of each oil cavern, and the layout range of the water curtain holes is within the enclosure of the vertical grouting curtain. The drainage system includes drainage pipes installed in the water cushion layer at the bottom of each oil cavern, and the drainage pipes are led out from the construction tunnel.

[0008] The oil transportation system includes an oil intake system and an oil outlet pipe installed in each oil cavern. The oil intake system includes an oil transportation shaft connecting the input oil station and the water diversion tunnel, an input oil pipeline installed in the water diversion tunnel and water curtain tunnel, and an oil transportation branch pipe connecting the input oil pipeline and each oil cavern. Oil from the input oil station is injected into each oil cavern through the input oil pipeline and the oil transportation branch pipe. The oil outlet pipe is led out through the construction tunnel and leads to a temporary oil depot installed outside the construction tunnel.

[0009] A further technical solution provided by the present invention: The oil cavern structure includes a monitoring system, which includes a water level and pressure monitoring device, a monitoring room located outside the mountain, a gate located at the inlet of the water diversion tunnel, a first solenoid valve installed on the drainage pipe, a second solenoid valve installed at the inlet of the input oil pipe, a third solenoid valve installed on the outlet oil pipe, and temperature sensors, oil pressure sensors, oil level sensors, gas pressure detectors, gas density detectors, and gas temperature detectors installed in each oil cavern. The water level and pressure monitoring device includes water level sensors and water pressure sensors installed at the bottom water cushion layer, water curtain tunnel, water diversion tunnel, and near the water source intake of the oil cavern. The signal output terminals of the water level sensors, water pressure sensors, temperature sensors, oil pressure sensors, oil level sensors, gas pressure detectors, gas density detectors, and gas temperature detectors are respectively connected to the signal input terminals of the controller in the monitoring room. The controller in the monitoring room is communicatively connected to the gate, the oil pump in the input oil station, and the first, second, and third solenoid valves.

[0010] The preferred technical solution provided by the present invention is as follows: the oil storage group is located in a mountain with intact rock mass, and the oil storage group includes multiple parallel gate-shaped tunnel-type oil storage tanks. The outer envelope of the oil storage group is square in plan. The construction tunnel is set horizontally and serves as a drainage corridor and an oil output corridor.

[0011] The preferred technical solution provided by this invention is as follows: The vertical grouting curtain is installed in the four directions of front, back, left, and right of the oil cavern group. Specifically, it is constructed from the gully above the highest position of the oil cavern towards the top surface of the oil cavern through the curtain construction tunnel and the grouting gallery. After the grouting chamber is constructed vertically through the curtain construction tunnel, and the anti-seepage grout is injected through the grouting gallery, a square barrel-shaped anti-seepage structure is formed. The horizontal grouting curtain is an anti-seepage curtain constructed diagonally downward at the bottom of the side wall of the cavern during the excavation of each oil cavern. The anti-seepage curtains on the sides of two adjacent oil caverns are connected as one unit and are connected as one unit with the anti-seepage bottom plate of the oil cavern.

[0012] The preferred technical solution provided by the present invention is as follows: the drainage system further includes a sewage treatment station, and the drainage pipe discharges excess collected water from the water cushion layer of the oil cavern by gravity flow to the sewage treatment station.

[0013] The preferred technical solution provided by the present invention is as follows: the construction tunnel is connected to each oil storage cavern through a transverse tunnel, and the construction of each oil storage cavern is carried out sequentially through the transverse tunnel. The distance between two adjacent oil storage caverns is 35-45m. After the construction of the oil storage cavern is completed and before oil injection, the connection between the construction tunnel and the transverse tunnel is sealed with a second sealing plug.

[0014] The preferred technical solution provided by the present invention is as follows: the oil distribution pipe is set between the water curtain tunnel and the top surface of each oil cavern, and a vertical oil pipe hole is provided between the water curtain tunnel and each oil cavern. The oil distribution pipe enters the oil cavern through the vertical oil pipe hole, and after the oil distribution pipe is buried, the gap between the vertical oil pipe hole and the oil distribution pipe is sealed. The oil outlet pipe is laid from the water cushion layer of each oil cavern to the temporary oil depot outside the construction tunnel entrance.

[0015] The preferred technical solution provided by the present invention is as follows: the gate is opened by a hoist, and the controller in the monitoring room is connected to the hoist via a control line; the inner wall of the water diversion tunnel is constructed with an anti-seepage layer, and the bottom elevation of the water diversion tunnel is higher than the elevation of the water curtain tunnel; the stable water source is a reservoir, lake or river with abundant and stable water flow, and its lowest water level is higher than the bottom of the water diversion tunnel, and the stable water source is supplied to the water curtain hole by natural flow.

[0016] To achieve the above-mentioned technical objectives, the present invention provides a method for constructing an underground water-sealed barrel-shaped oil storage structure, characterized by the following specific steps:

[0017] (1) Engineering survey: Through geological survey, select a mountain that is close to a stable water source and has no groundwater or an unstable groundwater source as the construction site for the water-diversion barrel-shaped water-sealed oil cavern. Preliminary plan of the mountain and water diversion line close to the water source is proposed. Engineering geological and hydrogeological surveys are carried out to select a suitable water diversion line. A mountain with intact rock mass is selected as the construction area of ​​the cavern group and the water diversion line.

[0018] (2) Oil storage cavern design: Construction design for the storage cavern and water diversion tunnel, construction tunnel, barrel-shaped water seal structure, water diversion system, drainage system and oil transportation system and monitoring system, and drawing design drawings;

[0019] (3) Excavation of construction tunnels and oil storage caverns: Construction tunnels are constructed from the side of the mountain near the road and extend horizontally to the construction area of ​​the cavern group. Oil storage caverns are excavated in sequence, with a distance of 35-45m between two adjacent oil storage caverns. The construction tunnels and caverns are excavated using the drill-and-blast method with smooth blasting. The construction tunnels are excavated with full-section excavation, and the caverns are constructed using the step method. The fractured zone and unstable rock mass in the construction tunnel and cavern group area are supported by shotcrete and anchor and consolidated by grouting. Local curtain grouting is carried out on concentrated leakage channels and areas. The construction tunnels are lined with reinforced concrete.

[0020] (4) Construction of the barrel-shaped water seal structure: During the excavation of the cave, a horizontal anti-seepage curtain is constructed diagonally downward from the bottom of the cave side wall, and the horizontal anti-seepage curtains on the sides of the adjacent cave and the anti-seepage bottom plate of the cave are connected to form a barrel-shaped water seal structure bottom anti-seepage curtain; the curtain construction tunnel is excavated from the side of the mountain at a position higher than the top of the cave, and the curtain construction tunnel extends from the outside of the mountain to the area above the cave arch. A ring-shaped horizontal grouting gallery is excavated along the area greater than the outer edge of the cave group through the curtain construction tunnel, and the vertical anti-seepage curtain of the barrel-shaped side wall is constructed vertically downward along the grouting gallery. The bottom end of the vertical anti-seepage curtain is lower than the bottom surface of the cave anti-seepage bottom plate, and the vertical anti-seepage curtain and the bottom anti-seepage curtain form a complete cylindrical water seal structure.

[0021] (5) Construction water diversion system: Multiple water curtain tunnels are excavated from the grouting gallery on one side to the grouting gallery on the other side. The grouting gallery also serves as a water curtain tunnel. Multiple water curtain holes are drilled horizontally between the water curtain tunnels and between the water curtain tunnels and the grouting gallery. Then, the connection between the curtain construction tunnel and the grouting gallery is sealed with a sealing plug. A horizontal or upward inclined water diversion tunnel is excavated from the grouting gallery near the water source to the water source slope. A gate and a hoist are installed at the inlet of the water diversion tunnel. The inner wall of the water diversion tunnel is treated with anti-seepage.

[0022] (6) Construction drainage system: During the construction of each tunnel, drainage pipes are buried in the water cushion layer of the tunnel and led out through the construction tunnel;

[0023] (7) Construction of the oil transportation system: Excavate oil transportation shafts downwards from the water source slope, and construct vertical oil pipe holes along the water curtain tunnel to the top of each cavern. Bury input oil pipes along the oil transportation shafts and water diversion tunnels. Install oil transportation branch pipes in each vertical oil pipe hole. The oil transportation branch pipes lead into the cavern. After the oil transportation branch pipes are installed and connected to the input oil pipes, seal the gap between the oil transportation branch pipes and the vertical oil pipe holes, and lead out the input oil pipes and connect them to the oil outlet pipes of the input oil station. The construction tunnel also serves as an oil discharge tunnel. During the construction of the cavern, an oil discharge pipe is buried at the bottom of the cavern. The oil discharge pipe is led out through the construction tunnel. Control valves are installed on both the input oil pipes and the oil discharge pipes.

[0024] (8) Sealing of underground storage and curtain wall construction tunnels, inclined tunnels and construction tunnels: According to the existing construction methods of oil underground storage, install other auxiliary structures and monitoring systems of oil underground storage, and after debugging, seal individual underground storage, underground storage construction tunnels and curtain wall construction tunnels;

[0025] (9) Test of water seal performance of barrel-shaped water seal structure under full water condition in grouting gallery and water curtain tunnel: Water is introduced into grouting gallery and water curtain tunnel through water diversion tunnel, and the water seal performance of barrel-shaped water seal structure is tested under full water condition in grouting gallery and water curtain tunnel, so that the rock mass in barrel-shaped water seal structure is saturated with water, to test the stability of rock mass in cave and verify the seepage volume of cave.

[0026] The preferred technical solution provided by the present invention is as follows: the monitoring system includes water level and water pressure monitoring, cavern surrounding rock deformation monitoring, gate control, oil level, oil pressure and oil temperature monitoring, cavern temperature, gas temperature monitoring, and installation and commissioning of pipeline gate valves and control devices.

[0027] The underground water-sealed barrel-shaped oil cavern of this invention is located within a mountain with hard, intact rock mass, no groundwater or unstable groundwater source, and situated near a stable water source. A barrel-shaped impermeable curtain is installed around the oil cavern complex. Water is diverted from the water source through a water diversion tunnel to a water curtain opening at the top of the cavern for hydraulic sealing. The horizontal construction tunnel, lower than the cavern floor, also serves as a drainage corridor. The barrel-shaped water seal system of this invention includes a vertical impermeable curtain around the cavern complex, a horizontal impermeable curtain between the cavern floor slabs, a water curtain tunnel, and water curtain openings. The water diversion system includes gates, tunnels, water pipelines, and control devices. The tunnel floor is slightly higher than the water curtain tunnel but lower than the lowest water level of the water source. The drainage system, located within the construction tunnel, discharges excess water from the cavern's water cushion layer to the surface by gravity. The oil transportation system gravity-flows oil from the surface into the cavern and from the cavern to the surface.

[0028] The barrel-shaped water seal method in this invention is also applicable to existing oil caverns; the monitoring system in this invention is the same as the existing monitoring system for oil caverns, including water level and pressure monitoring, cavern surrounding rock deformation monitoring, gate control, oil level monitoring, oil pressure monitoring, oil temperature monitoring, oil level detection, cavern temperature, gas monitoring (monitoring of volatile gases), air temperature monitoring, and installation and commissioning of pipeline gate valves and control devices.

[0029] The beneficial effects of this invention are:

[0030] 1. The present invention sets vertical and horizontal curtains on the sides and bottom of the cave complex, enclosing the entire cave complex in a barrel-shaped curtain, eliminating the need to set a seepage prevention curtain for each cave, thus greatly reducing the amount of seepage prevention curtain work and construction costs.

[0031] 2. The horizontal and near-horizontal construction tunnels and water diversion inclined tunnels of the present invention are more convenient than the existing inclined tunnel construction, and can significantly improve the construction progress.

[0032] 3. The barrel-shaped anti-seepage curtain and water diversion system of the present invention make the seepage of the cavern controllable and reduce the amount of sewage; the water diversion barrel-shaped water seal method expands the construction scope of underground oil caverns.

[0033] 4. The gravity-flow cavern drainage and oil transportation method of the present invention greatly reduces operating costs. Attached Figure Description

[0034] Figure 1 This is a cross-sectional layout diagram of the water-sealed barrel-shaped oil cavern in this invention.

[0035] Figure 2 yes Figure 1 Sectional view of AA;

[0036] Figure 3 This is a plan view of the cross-sectional layout of the water-sealed barrel-shaped oil cavern in this invention.

[0037] Figure 4 This is an enlarged vertical cross-sectional view of the barrel-shaped water seal curtain in this invention;

[0038] Figure 5 This is the control principle diagram of the present invention.

[0039] In the diagram: 1—mountain, 2—stable water source, 3—water diversion tunnel, 4—oil storage cavern, 5—seepage-proof bottom slab, 6—construction tunnel, 7—barrel-shaped water seal structure, 700—vertical grouting curtain, 701—horizontal grouting curtain, 8—first sealing plug, 9—transverse tunnel, 10—second sealing plug, 11—curtain construction tunnel, 12—grouting gallery, 13—water curtain tunnel, 14—water curtain hole, 15—gate, 16—gate hoist, 17—input oil station, 18—oil conveying shaft, 19—input oil pipeline, 20—oil conveying branch pipe, 21—vertical oil pipeline hole, 22—oil outlet pipe, 23—temporary oil depot, 24—monitoring room, 25—drainage pipe, 26—sewage treatment station, 27—first solenoid valve, 28—second solenoid valve, 29—third solenoid valve, 30—mountain gully. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] In the description of this invention, it should be understood that the terms "upper," "lower," "inner," "outer," "left," and "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0042] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, terms such as "set" and "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0043] The embodiment provides an underground water-sealed barrel-shaped oil cavern structure, such as... Figures 1 to 4As shown, the oil storage structure is located within a mountain 1 near a stable water source 2, where there is no groundwater or the groundwater source is unstable. It includes a construction tunnel 6, an oil storage group, a barrel-shaped water seal structure 7, a water diversion system, a drainage system, and an oil transportation system. The construction tunnel 6 extends from the side of the mountain 1 into the mountain 1 and connects with the oil storage group located within the mountain 1. The oil storage group is situated within the intact rock mass of the mountain 1 and includes multiple parallel, arch-shaped tunnel-type oil storage tanks 4. The outer envelope of the oil storage group is square in plan view. Each oil storage tank 4 is constructed through the construction tunnel 6. Each oil storage tank has a seepage-proof bottom plate 5, which is lower than the seepage-proof bottom plate 5 of each oil storage tank 4. After the construction of the oil storage tank 4 is completed, the connection between each oil storage tank 4 and the construction tunnel 6 is sealed using a first sealing plug 8. The construction tunnel 6 is horizontally positioned and serves as both a drainage corridor and an oil output corridor. The construction tunnel 6 is connected to each oil storage cavern 4 through a transverse tunnel 9, and the construction of each oil storage cavern 4 is carried out sequentially through the transverse tunnel 9. The distance between two adjacent oil storage caverns 4 is 35-45m. After the construction of the oil storage cavern 4 is completed and before oil injection, the connection between the construction tunnel 6 and the transverse tunnel 9 is sealed by the second sealing plug 10.

[0044] The embodiment provides an underground water-sealed barrel-shaped oil cavern structure, such as... Figures 1 to 4 As shown, the barrel-shaped water seal structure 7 includes a vertical grouting curtain 700 and a horizontal grouting curtain 701. The vertical grouting curtain 700 is installed in the four directions of front, back, left, and right of the oil cavern complex. Its bottom surface is lower than the bottom surface of the seepage-proof bottom plate of the oil cavern 4, and its top surface is higher than the highest point of the oil cavern 4. Specifically, the vertical grouting curtain 700 is constructed from the gully 13, which is higher than the highest point of the oil cavern 4, towards the top surface of the oil cavern 4 through the curtain construction tunnel 11 and the grouting gallery 12. After the vertical grouting chamber is constructed through the curtain construction tunnel 11, and the seepage-proof grout is injected through the grouting gallery 12, a square is formed. The structure is a cylindrical anti-seepage structure. The horizontal grouting curtain 701 is set between two adjacent oil caverns 4. The horizontal grouting curtain 701 is connected to the anti-seepage bottom plate 5 of each oil cavern 4 to form an integral anti-seepage surface, and together with the vertical grouting curtain 700, it forms a cylindrical anti-seepage structure that covers the sides and bottom of the oil cavern group. The horizontal grouting curtain 701 is an anti-seepage curtain that is constructed diagonally downward at the bottom of the side wall of the cavern during the excavation of each oil cavern 4. The anti-seepage curtains on the sides of two adjacent oil caverns 4 are connected as one unit, and are also connected to the anti-seepage bottom plate of the bottom of the oil cavern 4.

[0045] The embodiment provides an underground water-sealed barrel-shaped oil cavern structure, such as... Figures 1 to 4As shown, the water diversion system includes a water diversion tunnel 3 connected to a stable water source 2, multiple water curtain tunnels 13 and water curtain holes 14 arranged on the top surface of the oil cavern group. The water curtain tunnels 13 are arranged horizontally between the vertical grouting curtains 700 and are interconnected with the water diversion tunnel 3. The water curtain holes 14 are constructed from the water curtain tunnels 13 along the extension direction of each oil cavern 4, and the arrangement range of the water curtain holes 14 is within the enclosure of the vertical grouting curtains 700. The drainage system includes a drainage pipe 25 arranged in the water cushion layer at the bottom of each oil cavern 4. The drainage pipe 25 is led out from the construction tunnel 6. The drainage system also includes a sewage treatment station 24. The drainage pipe 25 discharges excess collected water from the water cushion layer of the oil cavern 4 by gravity flow to the sewage treatment station 24. The inner wall of the water diversion tunnel 3 is constructed with an anti-seepage layer, and the bottom elevation of the water diversion tunnel 3 is higher than the elevation of the water curtain tunnel 13; the stable water source 2 is a reservoir, lake or river with abundant and stable water flow, and its lowest water level is higher than the bottom of the water diversion tunnel 3. The stable water source 2 supplies water to the water curtain hole 14 by gravity.

[0046] The embodiment provides an underground water-sealed barrel-shaped oil cavern structure, such as... Figures 1 to 4 As shown, the oil transportation system includes an oil intake system and an oil outlet pipe 22 installed in each oil storage cavern 4. The oil intake system includes an oil transportation shaft 18 connecting the input oil station 17 and the water diversion tunnel 3, an input oil pipe 19 installed in the water diversion tunnel 3 and the water curtain tunnel 13, and an oil transportation branch pipe 20 connecting the input oil pipe 19 and each oil storage cavern 4. Oil from the input oil station 17 is injected into each oil storage cavern 4 through the input oil pipe 19 and the oil transportation branch pipe 20. The oil outlet pipe 22 is led out through the construction tunnel 6 and leads to a temporary oil depot 23 installed outside the construction tunnel 6. The oil distribution pipe 20 is installed between the water curtain tunnel 13 and the top surface of each oil cavern 4. A vertical oil pipe hole 21 is provided between the water curtain tunnel 13 and each oil cavern 4. The oil distribution pipe 20 enters the oil cavern 4 through the vertical oil pipe hole 21. After the oil distribution pipe 20 is installed, the gap between the vertical oil pipe hole 21 and the oil distribution pipe 20 is sealed. The oil outlet pipe 22 is laid from the water cushion layer of each oil cavern 4 to the temporary oil depot 23 outside the entrance of the construction tunnel 6.

[0047] The embodiment provides an underground water-sealed barrel-shaped oil cavern structure, such as... Figure 5As shown, the oil storage structure also includes a monitoring system, which includes a water level and pressure monitoring device, a monitoring room 24 located outside the mountain, a gate 15 located at the inlet of the water diversion tunnel 3, a first solenoid valve 27 installed on the drainage pipe 25, a second solenoid valve 28 installed at the inlet of the input oil pipe 19, a third solenoid valve 29 installed on the outlet oil pipe 22, and temperature sensors, oil pressure sensors, oil level sensors, gas pressure detectors, gas density detectors, and gas temperature detectors installed in each oil storage 4. The system includes water level sensors and water pressure sensors installed at the bottom water cushion layer of the oil cavern, in the water curtain tunnel, in the water diversion tunnel, and near the water source intake. The signal output terminals of the water level sensors, water pressure sensors, temperature sensors, oil pressure sensors, oil level sensors, gas pressure detectors, gas density detectors, and gas temperature detectors are respectively connected to the signal input terminals of the controller in the monitoring room 24. The controller in the monitoring room 24 is communicatively connected to the gate 15, the oil pump in the input oil station 17, the first solenoid valve 27, the second solenoid valve 28, and the third solenoid valve 29. The gate 15 is controlled to open by the hoist 16, and the controller in the monitoring room 24 is connected to the hoist 16 via a control line.

[0048] The following describes the detection method for the underground water-sealed barrel-shaped oil cavern structure of the present invention in conjunction with specific embodiments. Specifically, for a particular construction idea, the construction method includes engineering survey, cavern design, construction of the construction tunnel, cavern, water diversion tunnel and water curtain system, installation of oil and water pipelines, gate valves and monitoring systems, etc., and the specific steps are as follows:

[0049] (1) Engineering Survey: The topography of the mountain and reservoir area in a certain area meets the construction conditions of a water-diversion barrel-shaped water-sealed cavern. The mountain is about 500m high, 1000m wide, and more than 2000m deep. It is 2000m away from the reservoir. The rock of the mountain strata is granite. The arch elevation of the proposed cavern is 80m. The granite engineering rock mass in the area is grade II to III. The lowest elevation of the bottom of the ditch is 30m. The groundwater level is 10m. The groundwater is mainly replenished by rainfall and has a short retention time. The dead water level of the reservoir is 110m. The elevation of the mountain road is 20m.

[0050] (2) The design of the water-sealed oil cavern structure specifically includes:

[0051] a. The cavern design consists of 5 cavern groups, with a spacing of 40m between the caverns, arranged in parallel. The caverns are shaped like city gates, with a width of 20m, a height of 30m, an arch radius of 10m, a length of 1000m, a thickness of 40m between the caverns, and a reinforced concrete base slab thickness of 20cm.

[0052] b. Design of the underground construction tunnel: The entrance of the underground construction tunnel is located beside the mountain road. The construction tunnel is in the shape of a city gate, with a height of 12m, a width of 8m, an arch radius of 4m, a reinforced concrete secondary lining thickness of 15cm, a length of 500m, and a longitudinal slope of 0.3%. A drainage ditch is set on one side of the tunnel and an oil drainage ditch is set on the other side.

[0053] c. Design of the curtain construction tunnel: The bottom slab of the curtain construction tunnel is at an elevation of 100m, which is flush with the bottom slab of the curtain grouting gallery and water curtain tunnel. The entrance of the tunnel is located in a gully on one side of the mountain. The tunnel is shaped like a city gate, with a height of 12m, a width of 8m, an arch radius of 4m, a length of 300m, and a longitudinal slope of 0.3%. A drainage ditch is set on one side of the tunnel.

[0054] d. Design of the barrel-shaped water seal system: The grouting gallery connects to the curtain wall construction tunnel. The grouting gallery is square in plan, 1030m long and 280m wide. The grouting gallery is arched, 7.5m high and 5m wide, with an arch radius of 2.5m. The vertical curtain of the barrel-shaped curtain extends 5m below the tunnel floor slab from the grouting gallery, with a curtain thickness of 5m and three rows of curtain holes, each 55m deep. The horizontal curtain is located in the partition walls between the tunnel floor slabs, with three rows of curtain holes. These curtain holes are downward-sloping holes with an inclination angle of 15 degrees and a diameter of 75cm. The grouting gallery also serves as a water curtain tunnel on the outer edge of the tunnel complex. Three water curtain tunnels are arranged at equal intervals parallel to the short side of the grouting gallery along its long side. The cross-sectional dimensions of the water curtain tunnels are the same as those of the grouting gallery. Curtain holes are drilled into the cavern complex within the grouting gallery. The curtain holes are parallel to the long side of the grouting gallery, with a single hole length of 130m, a diameter of 110mm, a spacing of 10m, and a height of 1.2m above the bottom plate of the water curtain tunnel.

[0055] e. Design of the water diversion system: The water diversion tunnel is connected to the grouting gallery, which is 1500m long. The grouting gallery is in the shape of a city gate, with a height of 3m, a width of 2m, and a crown radius of 1m. It is supported by anchor spraying. The secondary lining of the fractured section and the water inlet is 15cm thick reinforced concrete. The water inlet is equipped with a gate and a hoist.

[0056] d. Drainage system design: From the water cushion layer of the floor of a single tunnel to the tunnel sealing block, a pit is excavated and a drainage steel pipe is pre-buried to the drainage ditch of the tunnel construction. The steel pipe has a diameter of 50cm and a wall thickness of 5cm. Gate valves and opening and closing devices are installed on the steel pipes. The drainage channel leads to the sewage collection and treatment pool at the entrance of the tunnel construction.

[0057] e. The design of the oil transportation system involves excavating an oil input shaft down the reservoir bank slope to the water diversion tunnel. The shaft has a diameter of 300cm and a depth of 100m, with a reinforced concrete secondary lining thickness of 15cm. The oil pipeline has a diameter of 80cm and is laid from the water diversion tunnel to the water curtain tunnel. The oil pipeline passes through the bottom plate of the water curtain tunnel and is excavated downwards to the upper part of the water cushion layer of the tunnel. The oil discharge pipeline is pre-buried outside the construction tunnel seal and then laid to the oil intake station at the entrance of the construction tunnel, where oil transportation equipment, instruments, and pipelines are installed.

[0058] f. The monitoring system design is the same as the existing cave monitoring system.

[0059] (3) Excavation of construction tunnels and oil storage caverns: Construction tunnels are constructed from the side of the mountain near the road and extend horizontally to the construction area of ​​the cavern group, and oil storage caverns are excavated in sequence; the construction tunnels and caverns are excavated using the drill and blast method and smooth blasting, the construction tunnels are excavated with full-section excavation, and the caverns are constructed using the step method; the fractured zone and unstable rock mass in the construction tunnel and cavern group area are supported by shotcrete and anchor and consolidated grouting, the concentrated leakage channels and areas are locally grouted with curtain grouting, and the construction tunnels are lined with reinforced concrete.

[0060] (4) Construction of the barrel-shaped water seal structure: During the excavation of the cave, a horizontal anti-seepage curtain is constructed diagonally downward from the bottom of the cave sidewall, and the horizontal anti-seepage curtains on the sides of the adjacent cave and the anti-seepage bottom plate of the cave are connected to form a barrel-shaped water seal structure bottom anti-seepage curtain; the curtain construction tunnel is excavated from the side of the mountain at a position higher than the top of the cave, and the curtain construction tunnel extends from the outside of the mountain to the area above the cave arch. A ring-shaped horizontal grouting gallery is excavated along the area greater than the outer edge of the cave group through the curtain construction tunnel, and the vertical anti-seepage curtain of the barrel-shaped sidewall is constructed vertically downward along the grouting gallery. The bottom end of the vertical anti-seepage curtain is lower than the bottom surface of the horizontal anti-seepage bottom plate of the cave, and the vertical anti-seepage curtain and the bottom anti-seepage curtain form a complete cylindrical water seal structure.

[0061] (5) Construction water diversion system: Multiple water curtain tunnels are excavated from the grouting gallery on one side to the grouting gallery on the other side. The grouting gallery also serves as a water curtain tunnel. Multiple water curtain holes are drilled horizontally between the water curtain tunnels and between the water curtain tunnels and the grouting gallery. Then, the connection between the curtain construction tunnel and the grouting gallery is sealed with a sealing plug. A horizontal or upward inclined water diversion tunnel is excavated from the grouting gallery near the water source to the water source slope. A gate and a hoist are installed at the inlet of the water diversion tunnel. The inner wall of the water diversion tunnel is treated with anti-seepage.

[0062] (6) Construction drainage system: During the construction of each tunnel, drainage pipes are buried in the water cushion layer of the tunnel and led out through the construction tunnel.

[0063] (7) Construction of the oil transportation system: Excavate oil transportation shafts downwards from the water source slope, and construct vertical oil pipe holes along the water curtain tunnel to the top of each cavern. Bury input oil pipes along the oil transportation shafts and water diversion tunnels. Install oil transportation branch pipes in each vertical oil pipe hole. The oil transportation branch pipes lead into the cavern. After the oil transportation branch pipes are installed and connected to the input oil pipes, seal the gap between the oil transportation branch pipes and the vertical oil pipe holes, and lead out the input oil pipes and connect them to the oil outlet pipes of the input oil station. The construction tunnel also serves as an oil discharge tunnel. During the construction of the cavern, an oil discharge pipe is buried at the bottom of the cavern. The oil discharge pipe is led out through the construction tunnel. Control valves are installed on both the input oil pipes and the oil discharge pipes.

[0064] (8) Sealing of underground storage and curtain wall construction tunnels, inclined tunnels and construction tunnels: According to the existing construction methods of oil underground storage, install other auxiliary structures and monitoring systems of oil underground storage, and after debugging, seal individual underground storage, underground storage construction tunnels and curtain wall construction tunnels; the monitoring system includes water level and water pressure hydrological monitoring, underground storage surrounding rock deformation monitoring, gate control, oil level, oil pressure and oil temperature monitoring, underground storage temperature, gas temperature monitoring and pipeline gate valves and control devices installation and debugging.

[0065] (8) Sealing of underground storage and curtain wall construction tunnels, inclined tunnels and construction tunnels: According to the existing construction methods of oil underground storage, install other auxiliary structures and monitoring systems of oil underground storage, and after debugging, seal individual underground storage, underground storage construction tunnels and curtain wall construction tunnels;

[0066] (9) Test of water seal performance of barrel-shaped water seal structure under full water condition in grouting gallery and water curtain tunnel: Water is introduced into grouting gallery and water curtain tunnel through water diversion tunnel, and the water seal performance of barrel-shaped water seal structure is tested under full water condition in grouting gallery and water curtain tunnel. The rock mass inside barrel-shaped water seal structure is saturated with water to test the stability of rock mass in cave, verify the seepage of cave, ensure the smooth flow of pipelines and the effectiveness of monitoring system, and provide a basis for cave sealing and project acceptance.

[0067] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An underground water-conducted barrel-shaped water-sealed oil reservoir structure, characterized in that: The petroleum cave structure is arranged in the mountain (1) with stable water source (2) and no underground water or unstable underground water source, and comprises a construction tunnel (6), a petroleum cave group, a barrel-shaped water sealing structure (7), a water diversion system, a drainage system and an oil delivery system, the construction tunnel (6) extends from the side of the mountain (1) to the inside of the mountain (1) and communicates with the petroleum cave group in the mountain (1), the petroleum cave group comprises a plurality of petroleum caves (4) arranged side by side, each petroleum cave (4) is formed by construction of the construction tunnel (6), and a seepage-proof bottom plate (5) is arranged at the bottom of each petroleum cave (4), the bottom plate of the construction tunnel (6) is lower than the seepage-proof bottom plate (5) of each petroleum cave (4), and the port for connecting each petroleum cave (4) and the construction tunnel (6) is blocked by the first blocking plug (8) after the construction of the petroleum cave (4) is completed. The barrel-shaped water sealing structure (7) comprises a vertical grouting curtain (700) and a horizontal grouting curtain (701), the vertical grouting curtain (700) is arranged around the petroleum cave group, the bottom of the vertical grouting curtain (700) is lower than the bottom of the seepage-proof bottom plate of the petroleum cave (4), and the top of the vertical grouting curtain (700) is higher than the highest part of the petroleum cave (4), the horizontal grouting curtain (701) is arranged between two adjacent petroleum caves (4), the horizontal grouting curtain (701) is integrated with the seepage-proof bottom plate (5) of each petroleum cave (4) to form a whole seepage-proof surface, and the horizontal grouting curtain (701) and the vertical grouting curtain (700) form a cylindrical seepage-proof structure for covering the side and bottom of the petroleum cave group. The water diversion system comprises a water diversion tunnel (3) connected with the stable water source (2), a plurality of water curtain tunnels (13) and water curtain holes (14) arranged on the top of the petroleum cave group, the water curtain tunnels (13) are transversely arranged between the vertical grouting curtains (700) and communicate with the water diversion tunnel (3), the water curtain holes (14) are formed by construction along the extension direction of each petroleum cave (4) from the water curtain tunnels (13), and the arrangement range of the water curtain holes (14) is located in the arrangement range of the vertical grouting curtains (700); the drainage system comprises a drainage pipe (25) arranged in the water cushion layer at the bottom of each petroleum cave (4), and the drainage pipe (25) is led out from the construction tunnel (6). The oil delivery system comprises an oil inlet system and an oil outlet pipe (22) arranged in each petroleum cave (4), the oil inlet system comprises an oil delivery shaft (18) connected with an input oil station (17) and the water diversion tunnel (3), an input oil pipe (19) arranged in the water diversion tunnel (3) and the water curtain tunnels (13), and an oil delivery branch pipe (20) connected with the input oil pipe (19) and each petroleum cave (4), and the petroleum in the input oil station (17) is injected into each petroleum cave (4) through the input oil pipe (19) and the oil delivery branch pipe (20); the oil outlet pipe (22) is led out from the construction tunnel (6) and leads to a temporary oil depot (23) arranged outside the construction tunnel (6).

2. A water-sealed underground barrel-shaped oil storage structure according to claim 1, characterized in that: The oil storage structure comprises a monitoring system, the monitoring system comprises a water level and water pressure monitoring device, a monitoring room (24) arranged outside the mountain, a gate (15) arranged at the inlet end of the water diversion tunnel (3), a first electromagnetic valve (27) arranged on the drain pipe (25), a second electromagnetic valve (28) arranged at the inlet end of the input oil pipe (19), a third electromagnetic valve (29) arranged on the oil outlet pipe (22), and a temperature sensor, an oil pressure sensor, an oil level sensor, a gas pressure detector, a gas density detector and a gas temperature detector arranged in each oil storage (4), the water level and water pressure monitoring device comprises a water level sensor and a water pressure sensor arranged beside the water cushion layer at the bottom of the oil storage, the water curtain tunnel, the water diversion tunnel and the water source water inlet; the signal output ends of the water level sensor, the water pressure sensor, the temperature sensor, the oil pressure sensor, the oil level sensor, the gas pressure detector, the gas density detector and the gas temperature detector are connected with the signal input ends of the controller in the monitoring room (24), and the controller in the monitoring room (24) is in communication connection with the gate (15), the oil pump in the input oil station (17), the first electromagnetic valve (27), the second electromagnetic valve (28) and the third electromagnetic valve (29).

3. A water-filled barrel-shaped underground oil storage structure according to claim 1 or 2, characterized in that: The oil storage group is arranged in a mountain (1) with complete rock mass, and comprises a plurality of parallelly arranged city gate-shaped tunnel type oil storages (4), and the outer envelope line of the oil storage group in the plane is square.

4. A water-filled barrel-shaped underground oil storage structure according to claim 1 or 2, characterized in that: The vertical grouting curtain (700) is arranged around the oil storage group in four directions, specifically, after the curtain construction tunnel (11) and the grouting gallery (12) are constructed from the mountain ditch (30) higher than the highest position of the oil storage (4) to the top surface of the oil storage (4), the vertical grouting cavity is constructed through the curtain construction tunnel (11), and the square barrel-shaped anti-seepage structure is formed after the anti-seepage grout is injected through the grouting gallery (12); the horizontal grouting curtain (701) is an anti-seepage curtain constructed obliquely downward at the bottom of the side wall of the oil storage (4) during the excavation of each oil storage (4), and the anti-seepage curtains on the sides of two adjacent oil storages (4) are integrated, and the anti-seepage bottom plate of the oil storage (4) is integrated.

5. A water-sealed underground barrel-shaped oil storage structure according to claim 1 or 2, characterized in that: The drainage system further comprises a sewage treatment station (26), and the drain pipe (25) is connected to the sewage treatment station (26) after the excess water in the water cushion layer of the oil storage (4) is drained by gravity.

6. A water-sealed underground barrel-shaped oil storage structure according to claim 1 or 2, characterized in that: The construction tunnel (6) is communicated with each oil storage (4) through the transverse tunnel (9), and each oil storage (4) is constructed in sequence through the transverse tunnel (9), the spacing between two adjacent oil storages (4) is 35-45 m, and after the construction of the oil storage (4) is completed, the second sealing plug (10) is used to seal the communication part between the construction tunnel (6) and the transverse tunnel (9) before oil injection.

7. A water-filled barrel-shaped underground oil storage structure according to claim 1 or 2, characterized in that: The oil delivery branch pipe (20) is arranged between the water curtain tunnel (13) and the top surface of each oil cavern (4), a vertical oil pipe hole (21) is arranged between the water curtain tunnel (13) and each oil cavern (4), the oil delivery branch pipe (20) enters the oil cavern (4) through the vertical oil pipe hole (21), and after the oil delivery branch pipe (20) is buried, the gap between the vertical oil pipe hole (21) and the oil delivery branch pipe (20) is sealed; the oil outlet pipe (22) is arranged from the water cushion layer in each oil cavern (4) to the temporary oil storage (23) outside the construction tunnel (6) opening.

8. A water-sealed underground barrel-shaped oil storage structure according to claim 2, characterized in that: The gate (15) is controlled to be opened by the opening and closing machine (16), the controller in the monitoring room (24) is connected with the opening and closing machine (16) through a control line; the inner wall of the water diversion tunnel (3) is constructed with a seepage prevention layer, and the bottom plate elevation of the water diversion tunnel (3) is higher than the elevation of the water curtain tunnel (13); the stable water source (2) is a reservoir, a lake or a river with abundant and stable water inflow, and the lowest water level is higher than the bottom plate of the water diversion tunnel (3); the stable water source (2) is self-flowing water supply to the water curtain hole (14).

9. A method of constructing a subterranean, water-filled, barrel-shaped, water- sealed, oil reservoir structure according to any one of claims 1 to 8, characterized in that The specific steps are as follows: (1) Engineering survey: through geological survey, a mountain body near the stable water source and without underground water or unstable underground water source is selected as the construction site of the water diversion type barrel-shaped water sealed oil cavern, and the mountain body near the water source and the water diversion line are initially selected for engineering geological and hydrogeological survey, and the appropriate water diversion line is selected, and the mountain body with complete rock mass is selected as the cavern group construction area and the water diversion line; (2) Oil cavern design: the construction design is carried out for the cavern, water diversion tunnel, construction tunnel, barrel-shaped water sealed structure, water diversion system, drainage system, oil delivery system and monitoring system, and design drawings are drawn; (3) Excavation of construction tunnel and oil cavern: the construction tunnel is constructed from the side of the mountain body near the road, and is horizontally extended to the cavern group construction area, and the oil caverns are excavated in sequence, and the distance between two adjacent oil caverns is 35-45m; the construction tunnel and the cavern are excavated by drilling and blasting method, smooth blasting, the construction tunnel is excavated by full-face method, and the cavern is constructed by bench method; the construction tunnel and the cavern group area are supported by anchor and grouting, and the concentrated leakage channel and the area are locally curtain grouting, and the construction tunnel is reinforced concrete lining; (4) Construction of barrel-shaped water sealed structure: during the excavation of the cavern, the horizontal seepage prevention curtain is constructed from the bottom of the side wall of the cavern, the horizontal seepage prevention curtain of the side of the adjacent cavern and the seepage prevention bottom plate of the bottom of the cavern are connected to form the bottom seepage prevention curtain of the barrel-shaped water sealed structure; the curtain construction tunnel is excavated from the side of the mountain body higher than the top surface of the cavern, the curtain construction tunnel extends from the outside of the mountain body to the area above the cavern vault, the ring-shaped horizontal grouting gallery is excavated along the area larger than the outer edge of the cavern group through the curtain construction tunnel, and the vertical seepage prevention curtain of the barrel-shaped side wall is vertically constructed along the grouting gallery, the bottom end of the vertical seepage prevention curtain is lower than the bottom surface of the seepage prevention bottom plate, and the vertical seepage prevention curtain and the bottom seepage prevention curtain form a complete cylindrical water sealed structure. (5) Construction water diversion system: a plurality of water curtain tunnels are excavated from the grouting gallery on one side to the grouting gallery on the opposite side, the grouting gallery also serves as the water curtain tunnel, and a plurality of water curtain holes are drilled horizontally between the water curtain tunnels and between the water curtain tunnels and the grouting gallery, then the curtain construction tunnel is sealed with a sealing plug at the connection part between the grouting gallery; a horizontal or upwardly inclined water diversion tunnel is excavated from the grouting gallery close to the water source to the water source slope, and a gate and a hoist are installed at the inlet of the water diversion tunnel, and the inner wall of the water diversion tunnel is treated for anti-seepage; (6) Construction drainage system: during the construction of each cavern, a drainage pipe is buried in the water cushion layer of the cavern, and the drainage pipe is led out through the construction tunnel; (7) Oil delivery system construction: an oil delivery shaft is excavated downward on the water source slope, and a vertical oil pipe hole is constructed to the top of each cavern along the water curtain tunnel, an input oil pipe is buried along the oil delivery shaft and the water diversion tunnel, an oil delivery sub-pipe is installed in each vertical oil pipe hole, the oil delivery sub-pipe leads to the cavern, after the oil delivery sub-pipe is installed and connected with the input oil pipe, the oil delivery sub-pipe is sealed between the vertical oil pipe hole, the input oil pipe is led out and connected with the oil outlet pipeline of the input oil station; the construction tunnel also serves as an oil discharge hole, an oil discharge pipe is buried at the bottom of the cavern during the construction of the cavern, the oil discharge pipe is led out through the construction tunnel, and control valves are arranged on the input oil pipe and the oil discharge pipe; (8) Cavern and curtain construction hole, inclined hole and construction tunnel hole sealing: according to the existing petroleum cavern construction method, other auxiliary structures and monitoring systems of the petroleum cavern are installed, debugged, and then a single cavern, cavern construction tunnel and curtain construction tunnel are sealed; (9) Bucket-shaped water sealing test under the full water state of the grouting gallery and the water curtain tunnel: water is led to the grouting gallery and the water curtain tunnel through the water diversion tunnel, and the water sealing property of the bucket-shaped water sealing structure is tested under the full water state of the grouting gallery and the water curtain tunnel, so that the rock mass in the bucket-shaped water sealing structure is saturated, the stability of the cavern rock mass is tested, and the water seepage amount of the cavern is verified.

10. A method of constructing a subterranean, water-filled, barrel-shaped, water- sealed, petroleum reservoir structure according to claim 9, characterized in that The monitoring system in step (8) includes water level and water pressure monitoring, cavern surrounding rock deformation monitoring, gate control, oil level, oil pressure and oil temperature monitoring, cavern temperature and gas temperature monitoring, and installation and debugging of pipeline gate valves and control devices.

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