Device for measuring interlayer seepage diameter of horizontal ellipsoid reservoir, its use and leakage calculation method

Abstract

The present invention discloses a device for measuring the seepage diameter of the interlayer of a horizontal ellipsoid reservoir, a method for using the device and calculating the leakage amount, including a gas tracer input port and an output rod, the output rod including a retractable pipe, a storage platform and a gas tracer output pipe; the retractable pipe can meet the different positions of the interlayer of the gas storage reservoir, and ensure that the output rod can rotate along the mud interlayer of the horizontal ellipsoid reservoir, the purpose is to make the gas tracer evenly spread around the mud interlayer of the horizontal ellipsoid reservoir, and ensure that the gas tracer can be evenly distributed around the mud interlayer of the horizontal ellipsoid reservoir. Gas seepage causes the gas tracer to move, so we can read the position information of the gas tracer through a computer and obtain the gas seepage distance of the natural gas at the mud interlayer position of the horizontal ellipsoid reservoir through simple calculation. The present invention innovatively measures the seepage distance of the interlayer of the horizontal ellipsoid salt cavern underground gas storage reservoir, and the device is simple in structure and easy to implement.

Description

Technical Field

[0001] The invention belongs to the technical field of geotechnical engineering, and in particular relates to a device for measuring the seepage diameter of an interlayer of a horizontal ellipsoid reservoir, a use thereof and a method for calculating the leakage amount. Background Art

[0002] As a storage place for natural gas and oil, underground salt rock reservoirs are bound to seep out along the surrounding rock of the cavity wall under the action of ultra-high operating pressure (osmotic pressure) and ground stress. The seepage distance and leakage of the storage medium in the surrounding rock are currently the main indicator parameters for evaluating the tightness of salt rock reservoirs during operation. Therefore, it is of great significance to study the seepage distance and leakage of interlayers in horizontal ellipsoidal salt cavern gas storage. The ideal gas tracer flows in the porous medium of the reservoir synchronously with the traced fluid, so that the injected gas source can be accurately identified, and the movement state of the injected gas source in the reservoir, such as the scope of influence, displacement effect, and breakthrough speed, can be monitored. Based on these data, the trend of directional flow of the fluid can be obtained, and relevant reservoir information such as the presence of flow barriers or diversion channels can be determined.

[0003] At present, the research on the seepage distance and leakage of deep layered salt cavern underground gas storage during operation is mainly carried out through theoretical deduction and numerical simulation, and relatively few technical means are used. Engineering experts mainly use technical means such as gas tracer micro-leakage monitoring technology to monitor whether the salt cavern gas storage is leaking, but do not directly measure the gas seepage distance and leakage of the salt cavern gas storage. Among them, the gas tracer micro-leakage monitoring technology mainly determines whether the container has micro-leakage by detecting the tracer content outside the closed container. However, since the important indicators for evaluating the tightness of the salt cavern gas storage are the seepage distance and leakage of the gas in the interlayer, simply monitoring whether there is leakage cannot meet the requirements for evaluating the tightness of the salt cavern gas storage. In order to make up for these shortcomings, many experts and scholars began to use theoretical deduction methods and finite element software to simulate the changes in the seepage distance and leakage of gas in the interlayer during the operation of the salt cavern gas storage. However, using theoretical deduction and numerical simulation methods to study these problems is definitely different from the actual situation. Summary of the invention

[0004] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a device for measuring the seepage diameter of the interlayer of a horizontal ellipsoid storage tank, a method for using it and calculating the leakage amount, so as to solve the problem that the prior art mainly uses technical means to monitor whether the salt cavern gas storage tank is leaking, but lacks direct measurement of the seepage distance and leakage amount of the gas in the interlayer of the salt cavern gas storage tank, and there is a gap between the theoretical derivation and numerical simulation methods and the actual situation.

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

[0006] A device for measuring the seepage diameter of a horizontal ellipsoid reservoir interlayer comprises: a gas tracer input port and an output rod, wherein the output rod comprises a telescopic pipe, a storage platform and a gas tracer output pipe;

[0007] The lower end of the gas tracer input port is connected to the upper end of the telescopic pipe fitting, the lower end of the telescopic pipe fitting is connected to the storage platform, a gas tracer output pipe is arranged below the storage platform, and the gas tracer output port on the gas tracer output pipe is inserted into the mud interlayer of the horizontal ellipsoid reservoir.

[0008] Preferably, the gas tracer input port is funnel-shaped, and the lower end of the funnel is connected to a retractable pipe.

[0009] Preferably, uniform holes are provided at the gas tracer output port.

[0010] Preferably, the telescopic pipe comprises: an external pipe, a positioning plate, an internal pipe and a buckle, one side of the positioning plate is the external pipe, the other side is the internal pipe, and the buckle is arranged at the end of the external pipe.

[0011] Preferably, a switch button is provided on the storage platform, and the switch button is arranged at the lower part of the storage platform, and is controlled to be opened and closed by a retractable pipe.

[0012] Preferably, the diameter of the gas tracer output pipe is equal to the thickness of the mud interlayer of the horizontal ellipsoid reservoir.

[0013] The present invention also discloses a method for using a device for measuring the seepage diameter of a horizontal ellipsoid reservoir interlayer, comprising:

[0014] The output rod is inserted into the mud interlayer of the horizontal ellipsoid reservoir, and a gas tracer input port is installed at the port of the output rod;

[0015] The gas tracer is input from the gas tracer input port, and the retractable pipe opens the storage platform by retracting, so that the gas tracer enters the gas tracer output pipe and is input into the horizontal ellipsoid storage tank through the gas tracer output port.

[0016] Preferably, the retractable pipe comprises: an external pipe, a positioning plate, an internal pipe and a buckle; the buckle is pulled to extend and retract the retractable pipe, and the elongation of the external pipe and the internal pipe generates an axial force, which generates pressure on the storage platform to open the storage platform, allowing the gas tracer to enter the gas tracer output pipe.

[0017] The present invention also discloses a method for calculating the leakage of a horizontal ellipsoid reservoir interlayer, comprising:

[0018] S1: Outputting gas tracer into the horizontal ellipsoid reservoir using a device for measuring the seepage diameter of the interlayer of the horizontal ellipsoid reservoir;

[0019] S2: Read the position information of the gas tracer to calculate the gas seepage distance of the natural gas in the interlayer of the gas storage reservoir;

[0020] S3: Substitute the calculated gas seepage distance into formula (III) to calculate the leakage amount;

[0021]

[0022] Where: a, b are the lengths of the major and minor axes of the gas storage section; r i is the seepage distance of the i-th interlayer; i - the thickness of the i-th interlayer; P r - pore pressure at seepage distance; L max -The maximum seepage distance of the i-th interlayer; φ i -Porosity of the ith interlayer.

[0023] Preferably, the formula (III) is derived from the following:

[0024] P0V cavern =P a V total (Ⅰ)

[0025] The calculation formula for gas leakage in rocks is:

[0026]

[0027] Where: P0-current air pressure; P a - atmospheric pressure; V cavern -The current volume of gas in the cave; V total -Total cave volume; P p - pore pressure; V P -Pore volume.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The invention discloses a device for measuring the seepage diameter of the interlayer of a horizontal ellipsoid reservoir, comprising a gas tracer input port and an output rod, wherein the output rod comprises a retractable pipe, a storage platform and a gas tracer output pipe; the retractable pipe can meet the different positions of the interlayer of the gas storage reservoir, and ensure that the output rod can rotate along the mud interlayer of the horizontal ellipsoid reservoir, so as to make the gas tracer evenly spread around the mud interlayer of the horizontal ellipsoid reservoir, and ensure that the gas tracer can be evenly distributed around the mud interlayer of the horizontal ellipsoid reservoir. The gas seepage causes the gas tracer to move, so that we can read the position information of the gas tracer through a computer and obtain the gas seepage distance of the natural gas at the mud interlayer position of the horizontal ellipsoid reservoir through simple calculation. The invention innovatively measures the seepage distance of the interlayer of the horizontal ellipsoid salt cavern underground gas storage reservoir, and the device is simple in structure and easy to implement, providing a new idea and method for the study of the seepage distance and leakage of the horizontal ellipsoid salt cavern underground gas storage reservoir.

[0030] The present invention discloses a method for calculating the leakage of an interlayer of a horizontal ellipsoid reservoir. According to the movement of a gas tracer caused by gas seepage, the position information of the gas tracer is read by a computer, and the gas seepage distance of natural gas at the mud interlayer position of the horizontal ellipsoid reservoir is obtained by simple calculation. Then, a calculation formula suitable for the leakage of a horizontal ellipsoid salt cavern gas storage in the interlayer is derived, and the leakage of the gas storage is easily calculated by bringing the gas seepage distance value into the formula. The gas seepage distance is estimated by observing the change distance of the position of the gas tracer, and the leakage is obtained by calculation. The method is simple and efficient, and provides a new idea and method for leakage research. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the structure of the device of the present invention;

[0032] Figure 2 This is a cross-sectional view of the gas tracer outlet;

[0033] Figure 3 It is a horizontal ellipsoid gas storage model;

[0034] Figure 4 It is a schematic diagram of the structure of a telescopic rotating rod;

[0035] Figure 5 This is a cross-sectional view of the gas tracer output tube.

[0036] Among them: 1-gas tracer input port; 2-retractable pipe; 3-storage platform; 4-gas tracer output pipe; 5-horizontal ellipsoid reservoir; 6-gas tracer output port; 7-uniform holes; 8-output pipe section; 9-mud interlayer; 10-salt rock layer; 11-external pipe; 12-positioning plate; 13-internal pipe. DETAILED DESCRIPTION

[0037] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0038] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0039] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0040] In order to achieve the above-mentioned purpose, the present invention provides a method for measuring the seepage distance of a horizontal ellipsoid salt cavern underground gas storage in an interlayer by using a measuring device, and calculating the leakage amount by using a formula. It is believed that this will have a certain effect on further research on the seepage distance and leakage amount of deep salt cavern underground gas storage.

[0041] See also Figure 1 to Figure 5 The present invention comprises a gas tracer input port 1, a telescopic pipe 2, a storage platform 3, a gas tracer output pipe 4 and a gas tracer output port 6; the lower end of the gas tracer input port 1 is connected to the upper end of the telescopic pipe 2, the lower end of the telescopic pipe 2 is connected to the storage platform 3, a gas tracer output pipe 4 is arranged below the storage platform 3, and the gas tracer output port 6 on the gas tracer output pipe 4 is inserted into the mud interlayer 9 of the horizontal ellipsoid reservoir 5; and the gas tracer input port 1 is funnel-shaped, and the gas tracer is added to the device from here.

[0042] The output rod can only rotate along the mud interlayer 9 of the horizontal ellipsoid reservoir 5, in order to evenly spread the gas tracer around the mud interlayer 9 of the horizontal ellipsoid reservoir 5. The gas tracer output port 6 is exactly at the same height as the mud interlayer 9, so that the output rod can ensure that the gas tracer can be evenly spread around the mud interlayer 9 of the horizontal ellipsoid reservoir 5. The gas tracer input port 1 is installed when in use and can be taken away when not needed. The tracer output rod can only move at the position of the mud interlayer 9. Because the position of the gas storage interlayer is different, the total length of the pipe required is different, so the telescopic pipe 2 can meet this requirement. A buckle device is provided at the end of the telescopic rod 2. Because the pipe is not heavy, the buckle is pulled to stretch the end of the telescopic pipe 2, and then the gas tracer output port 6 is rotated along the position of the mud interlayer 9.

[0043] The storage platform 3 has a gas tracer storage function. When the retractable pipe 2 is extended or retracted, the switch button is pressed once. Each time the switch button is pressed, the gas tracer can only be output once. The switch is placed at the bottom of the storage platform 3, between the top of the gas tracer output pipe 4 and the storage platform 3, and does not overlap with the interface of the tracer output pipe 4. See the structural schematic diagram of the retractable pipe 2. Figure 4 , including an outer tube 11, a positioning plate 12 and an inner tube 13. The retractable tube 2 is retracted by pulling the buckle ring. The axial force generated by the extension of the retractable tube 2 will generate pressure on the storage platform 3, thereby pressing the switch button under the storage platform 3, and then outputting a gas tracer. That is, the gas tracer is output once when the switch button is pressed once.

[0044] The diameter of the gas tracer output pipe 4 connected to the lower part of the storage platform 3 is consistent with the thickness of the mud interlayer 9.

[0045] The end surface of the gas tracer outlet at the lower part of the gas tracer outlet pipe 4 is provided with uniform holes to ensure uniform outflow of the gas tracer.

[0046] The gas permeation distance is estimated by observing the change in the position of the gas tracer, and the leakage amount is calculated. The device mainly connects the sensor to the computer through a wire. The principle is that the gas seepage in the horizontal ellipsoid reservoir is accompanied by the movement of the gas tracer. The position of the gas tracer is sensed by the sensor, and then the data is read by the computer. After a simple calculation, the seepage distance L can be obtained. The method of placing the sensor in the mud interlayer 9 is to place it by drilling. The diameter of the drill hole should be small and should not exceed 0.01 times the thickness of the mud interlayer, otherwise it will affect the measurement results of the device.

[0047] The formula for gas leakage of horizontal ellipsoid reservoir 5 in mud interlayer 9 is derived as follows:

[0048] According to Boyle's law,

[0049] P0V cavern =P a V total (Ⅰ)

[0050] Where: P0-current air pressure; P a - atmospheric pressure; V cavern -The current volume of gas in the cave; V total -Total volume of the cave.

[0051] The calculation formula for gas leakage in rocks is:

[0052]

[0053] Where: P p - pore pressure; V P -pore volume. That is, the following formula

[0054]

[0055] Where: a, b are the lengths of the major and minor axes of the gas storage section; r i is the seepage distance of the i-th interlayer; i - the thickness of the i-th interlayer; P r - pore pressure at seepage distance; L max -The maximum seepage distance of the i-th interlayer; φ i -Porosity of the ith interlayer.

[0056] See also Figure 1 , the present invention includes a gas tracer input port device, a retractable pipe device, a storage platform device, a gas tracer output port device, etc.;

[0057] The gas tracer input port 1 is funnel-shaped, the lower part of the gas tracer input port 1 is connected to the telescopic pipe 2, the lower part of the telescopic pipe 2 is connected to the storage platform 3, the lower part of the storage platform 3 is connected to the gas tracer output pipe 4, the lower part of the gas tracer output pipe 4 is connected to the gas tracer output port 6, and the gas tracer output port 6 is inserted into the mud interlayer 9 right below the horizontal ellipsoid reservoir 5.

[0058] See also Figure 2 The end face of the gas tracer outlet 6 includes uniform holes 7 and an output tube section 8.

[0059] See also Figure 3 , a horizontal ellipsoid gas storage model, including a salt rock layer 10 and a mud interlayer 9.

[0060] Implementation steps:

[0061] The gas tracer is added to the device from the gas tracer input port 1, and is stored in the storage platform 3 through the retractable pipe 2. The retractable rod 2 is stretched, and the gas tracer can only be output once after stretching, and then it is kept in the storage state. When output, it is sprayed along the uniform hole 7 at the mud interlayer 9 position of the horizontal ellipsoid reservoir 5. After repeated stretching, it can be ensured that the mud interlayer 9 position of the horizontal ellipsoid reservoir 5 is sprayed with gas tracer. Gas seepage causes the gas tracer to move with it, so we can read the position information of the gas tracer through a computer and obtain the gas seepage distance of natural gas at the mud interlayer 9 position of the horizontal ellipsoid reservoir 5 through simple calculation. Finally, by deriving a calculation formula suitable for the leakage amount of the horizontal ellipsoid salt cavern gas storage in the interlayer, it is easy to calculate the leakage amount of the gas storage by substituting the gas seepage distance value.

[0062] Method for calculating leakage using the above device:

[0063] The gas tracer position information is read by the computer in the device and the gas penetration distance L in the surrounding rock during the stable operation of the horizontal ellipsoid salt cavern gas storage is obtained through simple calculation. The long semi-axis a, short semi-axis b, and interlayer porosity of the horizontal ellipsoid salt cavern gas storage are measured by the existing measuring device. The thickness of the interlayer h, and these parameters are substituted into formula (III), the leakage amount of the horizontal ellipsoid salt cavern gas storage during safe operation can be obtained. The present invention is only a device for measuring the penetration distance. As for the measurement of other parameters, it is easy to measure them through existing devices. The present invention does not include the measurement of these devices. In addition, the method of the present invention is mainly based on theoretical derivation to obtain the relationship between the leakage amount of the horizontal ellipsoid salt cavern underground gas storage in the interlayer and the seepage distance. The main purpose is to calculate the leakage amount of the horizontal ellipsoid salt cavern underground gas storage in the interlayer according to the seepage distance obtained by the measuring device.

[0064] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A device for measuring the seepage diameter of a horizontal ellipsoidal reservoir interlayer, characterized in that: include: A gas tracer input port (1) and an output rod, wherein the output rod comprises a telescopic pipe (2), a storage platform (3) and a gas tracer output pipe (4); The lower end of the gas tracer input port (1) is connected to the upper end of the telescopic pipe (2), the lower end of the telescopic pipe (2) is connected to the storage platform (3), a gas tracer output pipe (4) is provided below the storage platform (3), and the gas tracer output port (6) on the gas tracer output pipe (4) is inserted into the mud interlayer (9) of the horizontal ellipsoid reservoir (5); The gas tracer input port (1) is funnel-shaped, and the lower end of the funnel is connected to a telescopic pipe (2); the telescopic pipe (2) comprises: an external pipe (11), a positioning plate (12), an internal pipe (13) and a buckle ring, one side of the positioning plate (12) is the external pipe (11), and the other side is the internal pipe (13), and the buckle ring is arranged at the end of the external pipe (11); The diameter of the gas tracer output pipe (4) is equal to the thickness of the mud interlayer (9) of the horizontal ellipsoid reservoir (5).

2. The device for measuring the seepage diameter of the interlayer of a horizontal ellipsoidal reservoir according to claim 1, characterized in that: The gas tracer output port (6) is provided with uniform holes (7).

3. The device for measuring the seepage diameter of the interlayer of a horizontal ellipsoidal reservoir according to claim 1, characterized in that: The storage platform (3) is provided with a switch button, which is arranged at the lower part of the storage platform (3) and is controlled to be on and off by the retractable pipe (2).

4. A method for using the device for measuring the seepage diameter of a horizontal ellipsoid reservoir interlayer according to any one of claims 1 to 3, characterized in that: include: The output rod is inserted into the mud interlayer (9) of the horizontal ellipsoid reservoir (5), and a gas tracer input port (1) is installed at the end of the output rod; The gas tracer is input from the gas tracer input port (1), and the retractable pipe (2) opens the storage platform (3) by retracting, so that the gas tracer enters the gas tracer output pipe (4) and is input into the horizontal ellipsoid storage tank (5) through the gas tracer output port (6).

5. The method for using the device for measuring the seepage diameter of the interlayer of a horizontal ellipsoidal reservoir according to claim 4, characterized in that: The retractable pipe (2) comprises: an external pipe (11), a positioning plate (12), an internal pipe (13) and a buckle; the buckle is pulled to extend and retract the retractable pipe (2), and the elongation of the external pipe (11) and the internal pipe (13) generates an axial force, which generates pressure on the storage platform (3) to open the storage platform (3), allowing the gas tracer to enter the gas tracer output pipe (4).

6. A method for calculating leakage of a device for measuring the seepage diameter of a horizontal ellipsoid reservoir interlayer according to any one of claims 1 to 3, characterized in that: include: S1: using a device for measuring the seepage diameter of the interlayer of the horizontal ellipsoid reservoir to output a gas tracer to the horizontal ellipsoid reservoir (5); S2: Read the position information of the gas tracer to calculate the gas seepage distance of the natural gas in the interlayer of the gas storage reservoir; S3: Substitute the calculated gas seepage distance into formula (III) to calculate the leakage amount; （Ⅲ） The formula (III) is derived from the following: （Ⅰ） The calculation formula for gas leakage in rocks is: （Ⅱ） Where: - Current air pressure; - atmospheric pressure; -Current volume of gas in the cave; -Total volume of the cave; - pore pressure; - pore volume; , is the length of the major and minor axes of the gas storage section; For the Interlayer seepage distance; -No. The thickness of the interlayer; - pore pressure at the seepage distance; -No. Maximum seepage distance of interlayer; -No. Interlayer porosity.

Images