In-situ test system suitable for research on ventilation effect of compressed air energy storage cavern

Abstract

The utility model provides an in-situ test system suitable for compressed air energy storage cavern ventilation effect research, which comprises a compressed air energy storage ventilation simulation system, a test system and a monitoring system, and is characterized in that the compressed air energy storage ventilation simulation system is an air blowing device and is arranged in a construction cavern, and the air blowing device comprises a compressor, a dryer and a liquid sprayer; the monitoring system is provided with a plurality of monitoring sections along the in-situ test hole, and the monitoring sections are used for monitoring water pressure, water quantity, surrounding rock displacement and surrounding rock resistivity. The system is provided with a water pressure monitoring section, a water volume monitoring section, a surrounding rock displacement monitoring section and a surrounding rock resistivity monitoring section, monitoring of key parameters such as surrounding rock water content, pore water pressure, surrounding rock displacement and resistivity under the ventilation effect is achieved, and new possibility is provided for researching potential influences of a ventilation system on surrounding rock and an excavation damage area.

Description

Technical Field

[0001] The utility model relates to the technical fields of compressed air energy storage and geotechnical engineering, and in particular to an in-situ test system suitable for studying ventilation effects of compressed air energy storage caverns. Background Art

[0002] During the construction and maintenance phase of compressed air energy storage caverns, full use of the already connected construction branch tunnels, inlet and outlet tunnels, and connecting tunnels to set up ventilation systems can ensure the orderly flow of air in the entire underground gas storage cavern group. However, the ventilation system will cause the water saturation of the surrounding rock and the excavation damage zone to decrease, thereby changing the thermal-hydraulic-mechanical coupling characteristics of the surrounding rock. Moreover, the sealing (air leakage) and stability issues of compressed air energy storage caverns are complex multi-field coupling problems involving the thermodynamics, seepage, and mechanics of the cavern. Therefore, studying the potential impact of the surrounding rock and excavation damage zone caused by the ventilation system is crucial to the bearing mechanism and economical and reasonable design of the compressed air energy storage cavern structure, especially the surrounding rock-lining-sealing layer system.

[0003] The existing technology lacks an in-situ test system suitable for studying the ventilation effects of compressed air energy storage caverns. This system can analyze the changes in key parameters such as surrounding rock moisture content, pore water pressure, surrounding rock displacement, and resistivity under ventilation, and clarify the potential impact of the ventilation system on the surrounding rock and excavation damage areas. Utility Model Content

[0004] The main purpose of the utility model is to provide an in-situ test system suitable for studying the ventilation effect of compressed air energy storage caverns, hoping to effectively solve the problems in the background technology.

[0005] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0006] An in-situ test system suitable for studying the ventilation effect of compressed air energy storage caverns, comprising a compressed air energy storage ventilation simulation system, a test system, and a monitoring system;

[0007] The compressed air energy storage ventilation simulation system is an air blowing device and is arranged in the construction tunnel. The air blowing device includes a compressor, a dryer and a liquid sprayer;

[0008] The test system includes an in-situ test hole air inlet pipe and an air outlet pipe, one end of the air inlet pipe and the air outlet pipe are connected to the construction hole, and the other end is connected to the in-situ test hole, the air inlet pipe and the air outlet pipe are respectively provided with at least two thermometers and hygrometers and flow meters, the top of the in-situ test hole is provided with at least two thermometers and hygrometers, the bottom of the in-situ test hole is provided with at least two water basin devices, and a weighing sensor is provided under the water basin device. The in-situ test hole is provided with closed doors at both ends;

[0009] The monitoring system is provided with a plurality of monitoring sections along the in-situ test hole, and the monitoring sections are used for monitoring water pressure, water volume, surrounding rock displacement and surrounding rock resistivity.

[0010] While adopting the above technical solutions, the present invention may also adopt or combine the following technical solutions:

[0011] As a preferred technical solution of the present utility model: there are four water pressure monitoring sections, and each water pressure monitoring section is provided with a number of micro pressure gauges.

[0012] As a preferred technical solution of the present invention: the measuring interval length of the micro pressure gauge is 30 cm. In a borehole with a total length of 40 cm, the measuring interval length is reduced to 15 cm.

[0013] As an optimal technical solution of the present utility model: there are two water volume monitoring sections, and each water volume monitoring section is provided with a plurality of capacitive hygrometers and dry-wet hygrometers.

[0014] As a preferred technical solution of the present invention: the capacitive hygrometer is installed in a groove 2 cm deep from the rock surface and is isolated from the atmosphere by a partition.

[0015] As a preferred technical solution of the present invention: there are two surrounding rock displacement monitoring sections, and each surrounding rock displacement monitoring section is provided with a number of micro extensometers.

[0016] As a preferred technical solution of the present invention: the surrounding rock resistivity monitoring section is monitored using a geoelectric array.

[0017] As a preferred technical solution of the present invention: the geoelectric array consists of 4 electrode chains, which are installed in a 1m deep borehole on a plane perpendicular to the axis of the in-situ test hole. Each electrode chain consists of a bundle of single-electrode cables, and each bundle of single-electrode cables is welded to a 5mm electrode fixed on the wall of a plastic half-pipe. The single-electrode cables are sealed in the half-pipe with silicone.

[0018] The utility model provides an in-situ test system suitable for studying the ventilation effect of compressed air energy storage caverns, which has the following beneficial effects: the system is equipped with a water pressure monitoring section, a water volume monitoring section, a surrounding rock displacement monitoring section and a surrounding rock resistivity monitoring section, so as to realize the monitoring of key parameters such as surrounding rock water content, pore water pressure, surrounding rock displacement and resistivity under ventilation, and provide new possibilities for studying the potential impact of the ventilation system on the surrounding rock and excavation damage area. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of an in-situ test system for studying the ventilation effect of a compressed air energy storage cavern provided by the present invention;

[0020] Figure 2 This is the distribution diagram of micro pressure gauges in the first and second water pressure monitoring sections;

[0021] Figure 3 This is the distribution diagram of micro pressure gauges in the third and fourth water pressure monitoring sections;

[0022] Figure 4 This is the layout diagram of the capacitance hygrometer and the dry-wet hygrometer for the first water monitoring section;

[0023] Figure 5 This is the layout diagram of the capacitance hygrometer and the wet-dry hygrometer for the second water volume monitoring section;

[0024] Figure 6 Layout diagram of the micro-extensometers for the first and second surrounding rock displacement monitoring sections;

[0025] Figure 7 This is a schematic diagram of the geoelectric array for monitoring the surrounding rock resistivity section;

[0026] Figure 8 Cross-section of drilling holes for electrodes;

[0027] In the figure: 1-construction hole; 2-in-situ test hole; 3-closed door; 4-air blowing device; 5-air inlet pipe; 6-air outlet pipe; 7-first water pressure monitoring section; 8-second water pressure monitoring section; 9-third water pressure monitoring section; 10-fourth water pressure monitoring section; 11-first water volume monitoring section; 12-second water volume monitoring section; 13-first surrounding rock displacement monitoring section; 14-second surrounding rock displacement monitoring section; 15-surrounding rock resistivity monitoring section; 21-water basin device; 22-thermohygrometer; 41-compressor; 42-dryer; 43-liquid sprayer; 51-inlet flowmeter; 52-inlet temperature and humidity meter; 61-outlet flowmeter; 62-outlet temperature and humidity meter; 151-electrode; 152-single electrode cable; 153-silica gel; 154-rock powder. DETAILED DESCRIPTION

[0028] The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

[0029] like Figure 1-8 As shown, an in-situ test system suitable for studying the ventilation effect of compressed air energy storage caverns includes a compressed air energy storage ventilation simulation system, a test system, and a monitoring system;

[0030] The compressed air energy storage ventilation simulation system is a blowing device 4 installed in the construction cave 1. The blowing device 4 includes a compressor 41, a dryer 42 and a liquid sprayer 43. During the test, an automatic valve is used to mix a portion of completely dry air with another portion of completely steam-saturated air to generate air with a specific temperature and humidity.

[0031] The test system includes an in-situ test hole 2, an air inlet pipe 5, and an air outlet pipe 6. One end of the air inlet pipe 5 and the air outlet pipe 6 is connected to the construction hole 1, and the other end is connected to the in-situ test hole 2. The air inlet pipe 5 and the air outlet pipe 6 are respectively provided with at least two thermometers and hygrometers and flow meters to measure the air flow, temperature and humidity of the air inlet pipe 5 and the air outlet pipe 6 during the test. The measurement results can be used to calculate the water balance during the test; at least two thermometers and hygrometers 22 are provided on the top of the in-situ test hole 2 to measure the temperature and humidity changes of the air in the hole during the test; at least two water basin devices 21 are provided at the bottom of the in-situ test hole 2 to measure the evaporation of free water during the test. A weighing sensor is provided under the water basin device 21 to continuously measure its weight loss and automatically replenish water. Closed doors 3 are provided at both ends of the in-situ test hole 2;

[0032] The monitoring system is equipped with multiple monitoring sections (9 in this embodiment) along the in-situ test hole 2. The monitoring sections are used to monitor water pressure, water volume, surrounding rock displacement, and surrounding rock resistivity. The depth of the monitoring section is set to 2m, which enables the monitoring of key parameters such as surrounding rock water content, pore water pressure, surrounding rock displacement and resistivity under ventilation, providing new possibilities for studying the potential impact of the ventilation system on the surrounding rock and excavation damage areas.

[0033] There are 4 water pressure monitoring sections, and each water pressure monitoring section is provided with a number of micro pressure gauges (24 in this embodiment).

[0034] The micro-pressure gauge consists of a mechanical packer and a filtered measuring interval. The measuring section is isolated by the packer and a resin section between the packer and the wellhead. In the vertically upward wellbore, resin is injected into the interface between the packer and the rock wall through another pipeline. A second packer is placed near the wellhead to keep the resin in the wellbore. The measuring interval length of the micro-pressure gauge is 30 cm. In a borehole with a total length of 40 cm, the measuring interval length is reduced to 15 cm.

[0035] There are two water volume monitoring sections, and each water volume monitoring section is provided with a number of capacitive hygrometers (14 in this embodiment) and dry-wet hygrometers (16 in this embodiment).

[0036] After installing the sensor, the borehole was filled with isolation grout, and the capacitive moisture meter was installed in a groove 2 cm deep from the rock surface and isolated from the atmosphere by a partition.

[0037] There are two surrounding rock displacement monitoring sections, each of which is equipped with several micro-extensometers (eight in this embodiment). The micro-extensometers are fixed to the end of the wellbore using an extension rod connected to a mechanical anchor and fixed to the rock surface through a bolt plate. The free space between the sucker rod and the rock in the well is filled with polyurethane foam to allow the sucker rod to move. Due to the expected small displacement, in order to minimize the error that may be caused by temperature changes, a temperature sensor is provided on the head of the extensometer for temperature compensation.

[0038] The surrounding rock resistivity monitoring section 15 is monitored using a geoelectric array.

[0039] The geoelectric array consists of four electrode chains installed in a 1-m-deep borehole on a plane perpendicular to the axis of the in-situ test hole, with the borehole arranged in a quarter-section.

[0040] Each electrode chain consists of a bundle of single-electrode cables 152, each of which is welded to a 5mm electrode 151 fixed to the wall of a plastic half-pipe. The single-electrode cables 152 are sealed in the half-pipe with silicone 153 and guided out of the drill hole to connect to a plug fixed to the cave wall. To ensure that the electrode 151 is pressed against the rock, the remaining space in the drill hole is filled with rock powder 154 and compacted with a stick.

[0041] Specifically, the in-situ test system for the study of ventilation effects of compressed air energy storage caverns is implemented in the following manner:

[0042] A compressed air energy storage power station has an installed capacity of 300MW, an operating pressure range of 7MPa-10MPa, 5.7 hours of energy storage hours, and 4 hours of power generation hours. The compressed air energy storage station is located in an area with inactive neotectonic activity, hard rock, minimal structural transformation, and good integrity. There are no regional faults, and fault formations are undeveloped. The surrounding rock mass is primarily Class II-III. The gas storage cavern has a typical circular cross-section and is lined with steel plate concrete. The excavation diameter is 12m, and the backfill concrete is 100cm thick.

[0043] S1: Excavation of the in-situ test hole: Based on the structural design of the compressed air energy storage power station gas storage hole, the axis of the in-situ test hole 2 is designed to be perpendicular to the construction hole 1. The typical cross-section is circular, and steel plate concrete lining is used. The excavation diameter is 12m, the excavation length is 10m, and the backfill concrete thickness is 100cm. Closed doors 3 are used to seal the two ends of the in-situ test hole 2. Two water basin devices 21 are placed at the bottom of the in-situ test hole 2 to measure the evaporation of free water during the test. The water basin device 21 is placed on a weighing sensor, which can continuously measure its weight loss and automatically replenish water.

[0044] S2: Compressed air energy storage ventilation simulation system layout: The air blowing device 4 is placed in the construction hole 1 and connected to the in-situ test hole 2 via an air inlet pipe 5 and an air outlet pipe 6. The device consists of a compressor 41, a dryer 42, and a liquid sprayer 43. During the test, an automatic valve is used to mix a portion of completely dry air with another portion of fully saturated steam air to produce air with a specific temperature and humidity.

[0045] S3: Monitoring system layout: The inlet duct 5 and the outlet duct 6 are respectively provided with an inlet flow meter 51 and an outlet flow meter 61, and an inlet temperature and humidity meter 52 and an outlet temperature and humidity meter 62 to measure the air flow, temperature and humidity of the inlet duct 5 and the outlet duct 6 during the test. At the same time, the measurement results can be used to calculate the water balance during the test. Two temperature and humidity meters 22 are arranged on the top of the in-situ test hole 2 to measure the temperature and humidity changes of the air in the hole during the test;

[0046] Nine sections were set up along the in-situ test tunnel 2, including four water pressure monitoring sections, two water volume monitoring sections, two surrounding rock displacement monitoring sections, and one surrounding rock resistivity monitoring section 15. The depth of the monitoring section was set to 2m, and 4, 8, 4, and 8 micro pressure gauges (such as 7 / 8 / 9 / 10) were installed at the first, second, third, and fourth water pressure monitoring sections, respectively. Figure 2-3 ); 7 capacitance hygrometers and 8 wet and dry hygrometers were installed at the first and second water monitoring sections 11 / 12 respectively (such as Figure 4-5 ), a capacitive sensor was installed in a groove 2 cm deep from the rock surface at the first and second water volume monitoring sections 11 / 12; four micro extensometers (such as Figure 6 ); The surrounding rock resistivity monitoring section 15 is monitored using a geoelectric array, which consists of four electrode chains installed in a borehole about 1m deep on a plane perpendicular to the axis of the in-situ test hole 2 (such as Figure 7-8 );

[0047] S4: Test preparation: In order to monitor the various hazardous sources during the compressed air test, four surveillance cameras were deployed to monitor the dynamics of the air inlet, air outlet, and closed door 3. Centralized monitoring was achieved in the central control room. Before the formal test, a trial run of the ventilation simulation system was conducted to monitor the gas flow in the air inlet duct 5 and the air outlet duct 6. The test was conducted after the test was qualified.

[0048] S5: Test process: Set the air flow rate to 20m 3 / h, humidity 80%, and ventilation time for 60 days for field tests.

[0049] The above-mentioned specific implementation methods are used to explain the present invention and are only preferred embodiments of the present invention, rather than limiting the present invention. Within the spirit of the present invention and the scope of protection of the claims, any modifications, equivalent replacements, improvements, etc. made to the present invention shall fall within the scope of protection of the present invention.

Claims

1. An in-situ test system suitable for studying the ventilation effect of compressed air energy storage caverns, characterized by: Including compressed air energy storage ventilation simulation system, test system and monitoring system; The compressed air energy storage ventilation simulation system is an air blowing device (4) and is arranged in the construction cave (1). The air blowing device (4) includes a compressor (41), a dryer (42) and a liquid sprayer (43); The test system comprises an in-situ test hole (2), an air inlet pipe (5), and an air outlet pipe (6); one end of the air inlet pipe (5) and the air outlet pipe (6) are connected to the construction hole (1), and the other end is connected to the in-situ test hole (2); the air inlet pipe (5) and the air outlet pipe (6) are respectively provided with at least two thermometers and hygrometers and flow meters; at least two thermometers and hygrometers (22) are provided on the top of the in-situ test hole (2); at least two water basin devices (21) are provided at the bottom of the in-situ test hole (2); a weighing sensor is provided under the water basin device (21); and closed doors (3) are provided at both ends of the in-situ test hole (2); The monitoring system is provided with a plurality of monitoring sections along the in-situ test hole (2), and the monitoring sections are used for monitoring water pressure, water volume, surrounding rock displacement, and surrounding rock resistivity.

2. The in-situ test system for studying the ventilation effect of compressed air energy storage caverns according to claim 1 is characterized in that: There are four water pressure monitoring sections, and each water pressure monitoring section is provided with a number of micro pressure gauges.

3. The in-situ test system for studying the ventilation effect of compressed air energy storage caverns according to claim 2 is characterized in that: The measuring interval length of the micro pressure gauge is 30 cm. In a borehole with a total length of 40 cm, the measuring interval length is reduced to 15 cm.

4. The in-situ test system for studying the ventilation effect of compressed air energy storage caverns according to claim 1 is characterized in that: There are two water volume monitoring sections, and each water volume monitoring section is provided with a plurality of capacitance hygrometers and dry-wet hygrometers.

5. The in-situ test system for studying the ventilation effect of compressed air energy storage caverns according to claim 4 is characterized in that: The capacitive hygrometer was installed in a groove 2 cm deep from the rock surface and isolated from the atmosphere by a partition.

6. The in-situ test system for studying the ventilation effect of compressed air energy storage caverns according to claim 1 is characterized by: There are two surrounding rock displacement monitoring sections, and each surrounding rock displacement monitoring section is provided with a number of micro extensometers.

7. The in-situ test system for studying the ventilation effect of compressed air energy storage caverns according to claim 1 is characterized by: The surrounding rock resistivity monitoring section (15) is monitored using a geoelectric array.

8. The in-situ test system for studying the ventilation effect of compressed air energy storage caverns according to claim 7 is characterized in that: The geoelectric array consists of four electrode chains installed in a 1m deep borehole on a plane perpendicular to the axis of the in-situ test hole. Each electrode chain consists of a bundle of single electrode cables (152). Each bundle of single electrode cables (152) is welded to a 5mm electrode (151) fixed on the wall of a plastic half-pipe. The single electrode cables (152) are sealed in the half-pipe with silicone rubber (153).

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