Telescopic deflation rod and shallow gas micro-disturbance in-situ controlled release system and method

Abstract

The present invention discloses a telescopic deflation rod and a shallow gas micro-disturbance in-situ controlled release system and method, including a gas detection system, a telescopic rod deflation system, a hydraulic loading system, a micro-disturbance gas release system, etc. The hydraulic loading system is used to press the gas detection system and the telescopic rod deflation system into a shallow gas reservoir formation, the gas detection system is used to detect the methane gas concentration in the soil layer, the telescopic rod deflation system is used to release the shallow gas in-situ, the water gas mud in the shallow gas reservoir enters the micro-disturbance gas release system through the telescopic rod deflation system, the micro-disturbance gas release system is used to separate gas from water and mud, and perform micro-disturbance deflation of gas by adjusting the shallow gas pressure. The device can realize the in-situ identification of shallow gas reservoirs in coastal areas containing catastrophic shallow gas and the micro-disturbance in-situ release of shallow gas reservoirs.

Description

Technical Field

[0001] The invention relates to a telescopic deflation rod and a shallow gas micro-disturbance in-situ controlled release system and method, which can realize in-situ identification of shallow gas and in-situ controlled release of shallow gas micro-disturbance. Background Art

[0002] The global temperature changes with time and has a certain periodicity, leading to periodic changes in sea level. Especially since the last glacial period, due to the temperature drop and subsequent rise, the coastal areas of the world have seen a transgression-regression sequence of strata. A large number of animal and plant remains were buried underground before they could decompose. In a long-term closed environment, organic matter was converted into methane and buried underground. Shallow gas is widely distributed in the coastal soft soils of the five continents around the world. During underground construction in coastal areas, the eruption of shallow gas can easily lead to disasters, seriously threatening the underground construction of coastal cities.

[0003] At present, there is no unified response measure for the geological disaster of shallow gas in the world. Disasters induced by shallow gas occur from time to time, such as the shallow gas eruption accident during the construction of Hangzhou Bay Bridge, the shallow gas eruption during the construction of Hangzhou Metro, and the splitting and sudden surge of a foundation pit in Canada due to shallow gas. At present, Hangzhou generally adopts the method of early gas release for shallow gas disasters, but the in-situ exploration of shallow gas and the controlled release technology of shallow gas are still blank. Therefore, the in-situ exploration of shallow gas and the controlled release equipment of surrounding disturbance need to be further developed.

[0004] Shallow gas mainly exists underground in the form of air pockets, and its main component is methane. Therefore, the detection of underground methane gas can be used to identify shallow gas reservoirs. At the same time, the deflation technology of shallow gas can be realized with the help of telescopic rod deflation technology, and the micro-disturbance deflation of shallow gas can be achieved with the help of gas-cement separation technology and pressure regulation technology. Summary of the invention

[0005] The object of the present invention is to provide a telescopic deflation rod and a shallow gas micro-disturbance in-situ controlled release system and method in view of the deficiencies in the prior art.

[0006] The present invention adopts the following technical scheme: a telescopic air-release rod, comprising a first hollow probe rod, a second hollow probe rod and a third hollow probe rod; the diameter of the first hollow probe rod is equal to the diameter of the third hollow probe rod, and the outer diameter of the second hollow probe rod is smaller than the inner diameter of the first hollow probe rod; both ends of the second hollow probe rod are provided with circumferential outward protrusions; both ends of the first hollow probe rod and the bottom end of the third hollow probe rod are provided with circumferential inward protrusions; the upper end of the second hollow probe rod is sleeved on the bottom end of the third hollow probe rod, and the lower end of the second hollow probe rod is sleeved on the top end of the first hollow probe rod; the sum of the lengths of the first hollow probe rod and the third hollow probe rod is greater than or equal to that of the second hollow probe rod; a air-release hole is provided in the middle of the second hollow probe rod; during the downward pressing process of the telescopic air-release rod, the first hollow probe rod and the third hollow probe rod are connected together, and the second hollow probe rod is enclosed therein; during the upward pulling process, the first hollow probe rod and the third hollow probe rod are separated, the second hollow probe rod is exposed in the soil layer, and the shallow gas is released through the air-release hole.

[0007] Furthermore, the vent holes are waist holes arranged vertically.

[0008] A shallow gas micro-disturbance controlled release system containing the telescopic deflation rod described above, further comprising:

[0009] a hydraulic loading system for pressing in the telescopic deflation rod,

[0010] a methane concentration detection probe placed at the bottom of the telescopic deflation rod for collecting the in-situ methane concentration at the insertion point of the telescopic deflation rod, and

[0011] A micro-perturbation deflation system for separating the gas-cement mixture released by a telescopic deflation rod and controlling the release of gas.

[0012] Furthermore, the hydraulic loading system is a crawler type static penetration vehicle

[0013] Furthermore, the micro-disturbance venting system includes a venting pipe, a separation box, an exhaust pipe, a drain outlet, and a pressure regulating valve; one end of the venting pipe is directly connected to the top of the third hollow probe rod, and the other end is connected to the bottom of the separation box; a drain outlet is set on the other side of the bottom of the separation box; the exhaust pipe is vertically installed at the top of the separation box, and the pressure regulating valve is installed on the exhaust pipe.

[0014] A shallow gas micro-disturbance in-situ release method using the telescopic test gas release rod comprises the following steps:

[0015] (1) The telescopic deflation rod is pressed into the soil layer to a certain depth, and the depth of the pressing is determined according to the actual project needs; then it is pulled up, and the methane concentration at different depths is monitored in real time during the pulling process.

[0016] (2) When the methane concentration in the soil layer begins to increase and exceeds 10%, it can be determined that there is shallow gas at this depth, and the telescopic gas release rod is pressed down again so that the gas release hole is located at the shallow gas storage depth;

[0017] (4) Pull up the telescopic bleed rod, and the mixture of gas, water and mud will be released from the bleed hole into the central channel of the third hollow probe rod. After the mud and water are separated by the separation box, the gas is directly discharged through the exhaust pipe and burned.

[0018] The beneficial effects of the present invention are:

[0019] The use of a telescopic deflation rod solves the problem of rod blockage during the deflation of shallow gas and the problem that the probe of the traditional deflation method cannot be recovered. The bottom end of the telescopic deflation rod is connected to a methane detection probe, and the in-situ identification of shallow gas is achieved by using the gas detection principle. The shallow gas release system based on the telescopic deflation rod of the present invention can achieve micro-disturbance controlled release of shallow gas, thereby effectively controlling surface subsidence. The invention can effectively achieve in-situ identification of shallow gas and micro-disturbance controlled deflation, avoiding shallow gas eruption accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the system structure of the present invention (front view);

[0021] Figure 2 It is a structural diagram of the telescopic rod (structural diagram of the open state);

[0022] Figure 3 It is a structural diagram of the telescopic rod (structural diagram of the closed state);

[0023] Figure 4 is a schematic diagram of the probe structure (front view);

[0024] Figure 5 It is a schematic diagram of the local structure of the wireless signal output port;

[0025] Among them, 1. shallow gas reservoir, 2. methane concentration detection probe, 3. first hollow probe rod, 4. third hollow probe rod, 5. hollow probe rod, 6. crawler, 7. table, 8. laptop computer, 9. hydraulic loading system, 10. wireless signal output port, 11. venting pipe, 12. console, 13. reaction frame, 14. reaction column, 15 hydraulic cylinder, 16. separation box, 17. micro-disturbance venting system, 18. drain port, 19. reaction plate, 20. valve, 21. pressure regulating valve, 22. Exhaust pipe, 23. Pressure regulating valve, 24. Membrane separation system, 25. Waterproof gasket, 26. Outward protrusion along the circumference, 27. Cable, 28. Inward protrusion along the circumference, 29. Waterproof membrane, 30. Second hollow probe rod, 31. Fixing screw, 32. Mud-water separation layer, 33. Water-gas separation layer, 34. Permeable stone, 35. Water-proof breathable membrane, 36. Filter, 37. Vent hole, 38. Vent section, 39. Infrared methane concentration sensor, 40. Wireless signal receiving end, 41. Wireless signal transmitter. DETAILED DESCRIPTION

[0026] The present invention provides a telescopic deflation rod, such as Figure 2As shown, it includes a first hollow probe rod 3, a second hollow probe rod 30 and a third hollow probe rod 4. The inner diameter and outer diameter of the first hollow probe rod 3 are equal to those of the third hollow probe rod 4, and the outer diameter of the second hollow probe rod 30 is smaller than the inner diameter of the first hollow probe rod 3; both ends of the second hollow probe rod 30 are provided with circumferential outward protrusions 26. The upper end of the second hollow probe rod 30 is sleeved on the bottom end of the third hollow probe rod 4, and the lower end of the second hollow probe rod 30 is sleeved on the top end of the first hollow probe rod 3; both ends of the third hollow probe rod 4 and both ends of the first hollow probe rod 3 are provided with circumferential inward protrusions 28 for limiting the position to prevent the second hollow probe rod 30 from sliding out of the first hollow probe rod 3 and the third hollow probe rod 4; the sum of the lengths of the first hollow probe rod 3 and the third hollow probe rod 4 is greater than or equal to that of the second hollow probe rod 30, ensuring that the first hollow probe rod 3 and the third hollow probe rod 4 can completely cover the vent hole 37 when they are closed and connected; A vent hole 37 is provided in the middle of the second hollow probe rod 30; during the downward pressing process of the telescopic vent rod, the third hollow probe rod 5 slides down, and the first hollow probe rod 3 slides up due to the resistance of the soil layer until the inner limit protrusion at the bottom contacts the bottom end of the second hollow probe rod 30, and the top end of the first hollow probe rod 3 contacts the bottom end of the third hollow probe rod 4 to achieve connection, and the second hollow probe rod 30 is enclosed therein; during the upward pulling process, the first hollow probe rod 3 and the third hollow probe rod 4 are separated, and the second hollow probe rod 30 is exposed in the soil layer, and the shallow gas is released through the vent hole 37. In practical applications, a plurality of hollow probe rods 5 of equal diameter can be connected to the top end of the third hollow probe rod 4 according to the actual depth of the soil layer. The telescopic vent rod of the present invention can prevent the rod from being blocked by silt during the downward pressing process on the one hand, and on the other hand, the detection probe is fixedly connected to the bottom end of the telescopic vent rod, which perfectly solves the problem that the probe of the traditional separate probe cannot be recovered. The telescopic vent rod can also be used in the field of exploration (in-situ collection of groundwater) and oil production, etc.

[0027] Preferably, the vent holes 37 are waist holes arranged vertically.

[0028] Based on the above telescopic deflation rod, the present invention provides a system that can simultaneously realize shallow gas reservoir identification and shallow gas micro-disturbance deflation. Figure 1 , including the above-mentioned telescopic deflation rod, a hydraulic loading system 9 for pressing the telescopic deflation rod, a methane concentration detection probe 2 for collecting the in-situ methane concentration, and a micro-disturbance deflation system 17 for separating the gas-cement mixture released by the telescopic deflation rod and controlling the gas release.

[0029] In this embodiment, a crawler static probe vehicle is used as the hydraulic loading system 17 to control the pressing of the telescopic deflation rod. The crawler static probe vehicle is first shifted to the intended deflation position, and the center of the crawler static probe vehicle is aligned with the deflation position. The deflation rod is driven downward one by one through the fixing hole of the static pressure equipment. There is a groove on the deflation rod, and the vertical insertion of the probe rod can be achieved through the combination of the clamping plate and the groove.

[0030] Methane concentration detection probe 2 Figure 4 As shown, it includes a cylindrical shell, a cone tip fixedly connected to the bottom of the cylindrical shell, a mud-water separation box 32, an air-water separation layer 33, an infrared methane concentration sensor 39 and a waterproof membrane 29 fixed to the top of the cylindrical shell; a hole is opened on the side wall of the cylindrical shell, and the mud-water separation box 32 is embedded and installed in the hole, and the inner side of the mud-water separation box 32 is covered with an air-water separation layer 33; the infrared methane concentration sensor 39 is installed on the inner wall of the cylindrical shell; when the methane concentration detection probe 2 is inserted into the soil layer, the methane gas in the soil enters the inside of the methane concentration detection probe 2 after the mud-water separation in the mud-water separation box 32 and the air-water separation in the air-water separation layer 33, and then the infrared methane concentration sensor 39 detects the concentration in real time, and sends it to the computer through a cable 27 and wireless transmission to realize real-time monitoring of the methane concentration. The top of the cylindrical shell of the methane concentration detection probe 2 is screwed with the bottom of the first hollow probe 3 by a thread.

[0031] The micro-disturbance deflation system 17 includes a deflation pipe 11, a separation box 16, an exhaust pipe 22, a drain port 18, and a pressure regulating valve 21; one end of the deflation pipe 11 is directly connected to the top of the third hollow probe rod 4 of the telescopic deflation rod, and the other end is connected to the bottom of the separation box 16; the separation box 16 is a common box, and a drain port 18 is arranged on the other side of the bottom of the separation box 16; an exhaust pipe 22 is vertically installed at the top of the separation box 16, and a pressure regulating valve 21 is installed on the exhaust pipe 22. When the shallow gas is released through the telescopic deflation rod, a mixture of gas, water, and mud is ejected into the separation box 16 through the exhaust pipe 11, and the water and mud are discharged through the drain port 18 after sedimentation; the gas is discharged and ignited through the exhaust pipe 22 at the top of the separation box 16. The micro-disturbance controlled release of the shallow gas can be achieved by adjusting the release pressure of the gas through the pressure regulating valve 21 on the exhaust pipe 22.

[0032] The signal of the methane concentration detection probe 2 is fed back upward through the cable 27. A wireless signal output port 10 is provided on the top side of the vent pipe 11 for installing a wireless signal transmitter 41. The wireless signal transmitter 41 is used to convert the electrical signal of the methane concentration detection probe 2 into a wireless signal for transmission, receive the signal through the wireless signal receiving end 40, and transmit the signal to the laptop computer 8 for real-time reception of the detection data of the methane concentration detection probe 2. In this embodiment, the wireless signal transmitter adopts Zhejiang Yuehe Technology LAU11, and the wireless signal receiving end adopts Zhejiang Yuehe Technology YH0104.

[0033] The following briefly describes the test process using the device of the present invention:

[0034] ① The bottom end of the first hollow probe rod 3 of the telescopic deflation rod and the top end of the methane concentration detection probe 2 are connected by threaded connection. The cable 27 connected to the infrared methane concentration sensor 39 in the methane concentration detection probe 2 passes through the first hollow probe rod 3, the second hollow probe rod 30, and the third hollow probe rod 4 of the telescopic deflation rod, and is connected to the wireless signal transmitter 41 fixed on the wireless signal output port 10 of the deflation pipe 11. The methane concentrations at different depths are received by the computer terminal.

[0035] ② The telescopic deflation rod is controlled by the hydraulic loading system 17 to be pressed into the soil layer to a certain depth. Since each hollow probe rod 5 is 1 meter long, it is pressed down 1 meter each time until it reaches a depth of 35 meters (the maximum burial depth of Hangzhou Metro is 35 meters). Then the upward pulling begins. During the upward pulling process, the methane concentration detection probe 2 detects the in-situ methane gas concentration at different depths in real time and sends it to the computer for real-time monitoring through the cable 27 and wireless transmission. When it is monitored that the methane concentration shows an increasing trend as the probe rod is pulled up, when the methane concentration exceeds 10%, it can be judged that there is shallow gas at this depth. The probe rod is pressed down again to a certain depth, and then the probe rod is pulled up. At this time, the deflation hole 37 is exposed in the soil layer; in general, the depth of the re-pressing should be greater than the sum of the lengths of the first hollow probe rod 3 and the methane concentration detection probe 2. In this example, the length of the first hollow probe rod 3 is 0.3 meters, the length of the second hollow probe rod 30 is 0.8 meters, the length of the third hollow probe rod 4 is 0.7 meters, the length of the methane concentration detection probe is 0.8 meters, and each hollow probe rod 5 is 1 meter long. Therefore, each time it is pressed down 1 meter, when the methane concentration is monitored to exceed 10%, continue to press down to a depth greater than 1.5 meters.

[0036] ③ After pulling out the probe rod, observe whether there is gas, water or mud eruption at the rod end. When eruption occurs, directly ignite the tail end of the vent pipe 22, and use the pressure regulating valve 21 to adjust to the required pressure to control the micro-disturbance release of the gas.

[0037] ④When the air pressure drops to 0, continue to pull up the probe rod until shallow gas appears again. Repeat steps ②③ until the probe rod is completely pulled up.

[0038] ⑤Disassemble the equipment and prepare for micro-disturbance deflation of the next hole.

[0039] After the test, separate the systems and prepare for the next set of tests.

Claims

1. A telescopic deflation rod, characterized in that: The invention comprises a first hollow probe rod (3), a second hollow probe rod (30) and a third hollow probe rod (4); the first hollow probe rod (3) and the third hollow probe rod (4) have the same inner diameter and outer diameter, and the outer diameter of the second hollow probe rod (30) is smaller than the inner diameter of the first hollow probe rod (3); both ends of the second hollow probe rod (30) are provided with circumferential outward protrusions (26); both ends of the first hollow probe rod (3) and the bottom end of the third hollow probe rod (4) are provided with circumferential inward protrusions (28); the second hollow probe rod (30) The upper end is sleeved on the bottom end of the third hollow probe rod (4), and the lower end of the second hollow probe rod (30) is sleeved on the top end of the first hollow probe rod (3); the sum of the lengths of the first hollow probe rod (3) and the third hollow probe rod (4) is greater than or equal to the length of the second hollow probe rod (30); a venting hole (37) is provided in the middle of the second hollow probe rod (30); when the telescopic venting rod is pressed downward, the first hollow probe rod (3) and the third hollow probe rod (4) are connected together, and the second hollow probe rod (30) is enclosed therein; During the pulling-up process, the first hollow probe rod (3) and the third hollow probe rod (4) are separated, the second hollow probe rod (30) is exposed in the soil layer, and the shallow gas is released through the venting hole (37).

2. The telescopic deflation rod according to claim 1, characterized in that: The air release hole (37) is a waist hole arranged vertically.

3. A shallow gas micro-disturbance controlled release system of the telescopic deflation rod according to claim 1, characterized in that: Also includes: a hydraulic loading system for pressing in the telescopic deflation rod, a methane concentration detection probe (2) disposed at the bottom of the telescopic deflation rod and used to collect the in-situ methane concentration at the insertion point of the telescopic deflation rod, and A micro-perturbation deflation system (17) is provided for separating the gas-cement mixture released by the telescopic deflation rod and controlling the gas release.

4. The shallow gas micro-disturbance controlled release system according to claim 3 is characterized in that: The hydraulic loading system is a tracked static penetration vehicle.

5. The shallow gas micro-disturbance controlled release system according to claim 3 is characterized in that: The micro-disturbance deflation system (17) comprises a deflation pipe (11), a separation box (16), an exhaust pipe (22), a drain port (18), and a pressure regulating valve (21); one end of the deflation pipe (11) is directly connected to the top end of the third hollow probe (4), and the other end is connected to the bottom end of the separation box (16); the drain port (18) is arranged on the other side of the bottom end of the separation box (16); the exhaust pipe (22) is vertically installed at the top end of the separation box (16), and the pressure regulating valve (21) is installed on the exhaust pipe (22).

6. A shallow gas micro-disturbance in-situ release method according to the shallow gas micro-disturbance controlled release system of claim 5, characterized in that: The steps include: (1) Press the telescopic deflation rod into the soil layer to a certain depth, the depth of which is determined according to the actual project needs; then pull it up, and monitor the methane concentration at different depths in real time during the pulling process; (2) When the methane concentration in the soil layer begins to increase and exceeds 10%, it can be determined that there is shallow gas at this depth, and the telescopic deflation rod is pressed down again so that the deflation hole (37) is located at the shallow gas storage depth; (3) Pull the telescopic deflation rod upwards, and the mixture of gas, water and mud enters the central channel of the third hollow probe rod (4) from the deflation hole (37) and is discharged. After the mud and water are separated by the separation box (16), the gas is directly discharged through the exhaust pipe (22) and burned.

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