GB2622297A

GB2622297A - Method and structure for measuring liquid level of geothermal well

Info

Publication number: GB2622297A
Application number: GB2309451.9A
Authority: GB
Inventors: Li Hongyan; Gao Xiaorong; Sun Caixia; Lu Xingchen; Ren Xiaoqing; Dong Wenbin; Xu Yong; Yin Jianxin
Original assignee: SINOPEC GREEN ENERGY GEOTHERMAL DEV CO Ltd
Current assignee: SINOPEC GREEN ENERGY GEOTHERMAL DEV CO Ltd
Priority date: 2022-08-23
Filing date: 2023-06-22
Publication date: 2024-03-13
Also published as: NL2035267A; CN115218990A; NL2035267B1; GB202309451D0

Abstract

A method and/or a structure for measuring a liquid level of a geothermal well 10 includes a directional pipeline 20 communicating with and adjacent to the geothermal well. The directional pipeline connects with a part of the geothermal well which is below a liquid surface, and a measurement device 30, such as a rope, is used for measuring the liquid level in the pipeline to determine the liquid level in the geothermal well; the geothermal well may contain a submersible pump 90 and associated pipeline 80. The wellhead of the geothermal well and an upper port of the directional pipeline can be sealed, and a lower end of the directional pipeline connects the geothermal well below the liquid surface. A part of the geothermal well above the liquid surface and a part of the directional pipeline above the liquid surface can be interconnected (70 Fig. 5), and/or an annulus pressure in both the geothermal well and the directional pipeline can be monitored, and either the interconnected portion and/or the annulus pressure can be used in determining the liquid level measurement. A pressure regulating device 60 connected with the directional pipeline and a first pressure gauge 40 and a second pressure gauge 50 may be used to regulating the annulus pressure in the directional pipeline such that it is equal to the geothermal well annulus pressure.

Description

METHOD AND STRUCTURE FOR MEASURING LIQUID LEVEL OF GEOTHERMAL

WELL

TECHNICAL FIELD

100011 The present disclosure relates to the field of geothermal measurement, and in particular, to a method for measuring a liquid level of a geothermal well and a structure for measuring a liquid level of a geothermal well.

BACKGROUND

100021 When a geothermal well is operating in a heating season, in order to prevent air or other harmful gases from entering underground to pollute geothermal water, both a wellhead and a surface pipeline are generally in a closed connection state. In a running process of the geothermal well, an underground water level needs to be monitored frequently. In this mode, a conventional measuring line cannot be lowered to the underground and cannot acquire true data of an underground liquid level.

100031 In order to solve the problems, two manners are mainly used for measuring the underground liquid level in solutions in the conventional art: 1) a sonic liquid-level meter is mounted at a wellhead position, sound waves are reflected at the underground liquid level through propagation of sound, and the underground liquid level is calculated by receiving reflected sound waves; this method is usually disturbed by other objects underground, and the reflected sound waves are often not reflected from the liquid surface, resulting in distortion of the data acquired at the liquid level; 2) a small hole is formed at the wellhead position and a measuring line is lowered to measure the underground liquid level; at this moment, underground air will enter the underground to cause oxidation reactions with an underground liquid or equipment, resulting in equipment corrosion and water pollution; and in addition, there is usually a phenomenon of obstruction during the process of lowering the measuring line due to the existence of a water pumping tubular column.

SUMMARY

100041 A main objective of the present disclosure is to provide a method for measuring a liquid level of a geothermal well and a structure for measuring a liquid level of a geothermal well to at least solve the problems of distortion of liquid level data acquired in a geothermal well liquid level measurement process in the conventional art and equipment corrosion and water pollution caused by air entering underground.

[0005] To achieve the above objective, according to a first aspect of the present disclosure, a method for measuring a liquid level of a geothermal well is provided, which includes: drilling a directional pipeline which is communicated with a geothermal well and is adjacent to the geothermal well, where a communication point between the directional pipeline and the geothermal well is located below a liquid surface of the geothermal well; sealing both a wellhead of the geothermal well and an upper port of the directional pipeline; respectively monitoring and acquiring an annulus pressure in the geothermal well and an annulus pressure in the directional pipeline in a case that the liquid level of the geothermal well is in a stable state; and measuring the liquid level in the directional pipeline to obtain the liquid level of the geothermal well in a case that the annulus pressure in the geothermal well is equal to the annulus pressure in the directional pipeline.

[0006] Further, in a case that the annulus pressure in the geothermal well is not equal to the annulus pressure in the directional pipeline, the method for measuring a liquid level of a geothermal well further includes: regulating the annulus pressure in the directional pipeline through a pressure regulating device arranged in the directional pipeline; and repeatedly monitoring and acquiring the annulus pressure in the geothermal well and the annulus pressure in the directional pipeline until the annulus pressure in the geothermal well is equal to the annulus pressure in the directional pipeline.

[0007] Further, in a case of monitoring and acquiring the annulus pressure in the geothermal well and the annulus pressure in the directional pipeline the method for measuring a liquid level of a geothermal well further includes: respectively setting pressure gauges in the geothermal well and the directional pipeline; and respectively monitoring and acquiring the annulus pressure in the geothermal well and the annulus pressure in the directional pipeline through the pressure gauges.

[0008] According to a second aspect of the present disclosure, a method for measuring a liquid level of a geothermal well is provided, which includes: drilling a directional pipeline which is communicated with a geothermal well and is adjacent to the geothermal well, a communication point between the directional pipeline and the geothermal well being located below a liquid surface of the geothermal well; sealing both a wellhead of the geothermal well and an upper port of the directional pipeline; communicating a part above the liquid surface of the geothermal well and a part above the liquid surface of the directional pipeline through a communicating pipeline formed between the geothermal well and the directional pipeline; and measuring a liquid level in the directional pipeline to obtain the liquid level of the geothermal well.

[0009] According to a third aspect of the present disclosure, a structure for measuring a liquid level of a geothermal well is provided, which includes: a geothermal well; a directional pipeline, formed adjacent to the geothermal well, a lower end of the directional pipeline being communicated with a part below a liquid surface of the geothermal well; and a measurement part, arranged in the directional pipeline, the measurement part being used for measuring a liquid level in the directional pipeline to obtain the liquid level of the geothermal well.

[0010] Further, both a wellhead of the geothermal well and an upper port of the directional pipeline are sealed. 100111 Further, the stincture for measuring a liquid level of a geothermal well further includes: a first pressure gauge arranged in the geothermal well, the first pressure gauge being used for monitoring and acquiring an annulus pressure in the geothermal well; and a second pressure gauge arranged in the directional pipeline, the second pressure gauge being used for monitoring and acquiring the annulus pressure in the directional pipeline.

100121 Further, the structure for measuring a liquid level of a geothermal well further includes: a pressure regulating device communicated with the directional pipeline and connected to each of the first pressure gauge and the second pressure gauge, the pressure regulating device being used for regulating the annulus pressure in the directional pipeline, so that the annulus pressure in the directional pipeline is equal to the annulus pressure in the geothermal well.

[0013] Further, the structure for measuring a liquid level of a geothermal well further includes: a communicating pipeline, formed between the geothermal well and the directional pipeline to communicate a part above the liquid surface of the geothermal well and a part above the liquid surface of the directional pipeline.

100141 Further, the measurement part is a measuring rope.

100151 The method for measuring a liquid level of a geothermal well in the technical solution of the present disclosure includes: drilling the directional pipeline which is communicated with the geothermal well and is adjacent to the geothermal well, where the communication point between the directional pipeline and the geothermal well is located below the liquid surface of the geothermal well; sealing both the wellhead of the geothermal well and the upper port of the directional pipeline; respectively monitoring and acquiring the annulus pressure in the geothermal well and the annulus pressure in the directional pipeline in a case that the liquid level of the geothermal well is in a stable state; and measuring the liquid level in the directional pipeline to obtain the liquid level of the geothermal well in a case that the annulus pressure in the geothermal well is equal to the annulus pressure in the directional pipeline. Therefore, in a process of measuring the liquid level of the geothermal well, the directional pipeline will not affect a normal operation of measurement equipment, and the accuracy of the measured data is ensured. Meanwhile, ground air is prevented from entering the geothermal well, and equipment corrosion and water pollution are avoided. The problems of distortion of liquid level data acquired in a geothermal well liquid level measurement process in the conventional art and equipment corrosion and water pollution caused by air entering underground are solved.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The specification accompanying drawings, which constitute a part of the present application, are used to provide a further understanding of the present disclosure, and exemplary embodiments of the present disclosure and the description thereof are used to explain the present disclosure, but do not constitute improper limitations to the present disclosure. In the accompanying drawings: [0017] FIG. 1 is a flow block diagram of an optional first method for measuring a liquid level of a geothermal well according to an embodiment of the present disclosure; [0018] FIG. 2 is a flow block diagram of an optional second method for measuring a liquid level of a geothermal well according to an embodiment of the present disclosure; [0019] FIG. 3 is a flow block diagram of an optional third method for measuring a liquid level of a geothermal well according to an embodiment of the present disclosure; [0020] FIG. 4 is a schematic diagram of an optional first structure for measuring a liquid level of a geothermal well according to an embodiment of the present disclosure; and [0021] FIG. 5 is a schematic diagram of an optional second structure for measuring a liquid level of a geothermal well according to an embodiment of the present disclosure.

[0022] The above accompanying drawings include the following reference signs: [0023] 10, geothermal well; 20, directional pipeline; 30, measurement part; 40, first pressure gauge; 50, second pressure gauge; 60, pressure regulating device;70, communicating pipe; 80, water pumping pipeline; and 90, submersible pump.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] It is to be noted that embodiments in the present application and features in the embodiments may be combined without a conflict. The present disclosure is described in detail below with reference to the accompanying drawings and in combination with the embodiments. [0025] A first embodiment of the present disclosure discloses a method for measuring a liquid level of a geothermal well, as shown in FIG. 1, which specifically includes the following steps: [0026] S102: a directional pipeline which is communicated with a geothermal well and is adjacent to the geothermal well is drilled, and a communication point between the directional pipeline and the geothermal well is located below a liquid surface of the geothermal well; 100271 S104: both a wellhead of the geothermal well and an upper port of the directional pipeline are sealed; [0028] S106: an annulus pressure in the geothermal well and an annulus pressure in the directional pipeline are respectively monitored and acquired in a case that the liquid level of the Geothermal well is in a stable state. and [0029] S108: the liquid level in the directional pipeline is measured to obtain the liquid level of the geothermal well in a case that the annulus pressure in the geothermal well is equal to the annulus pressure in the directional pipeline.

[0030] In a process of measuring the liquid level of the geothermal well, the geothermal well is communicated with a lower end of the directional pipeline to form a communicating vessel; there is no pipeline or other obstacles in the directional pipeline, which will not affect a normal operation of measurement equipment, thereby ensuring the accuracy of the measured data; and in addition, air can be prevented from entering the geothermal well by measuring the liquid level through the directional pipeline, and equipment corrosion and water pollution are avoided. The problems of distortion of liquid level data acquired in a geothermal well liquid level measurement process in the conventional art and equipment corrosion and water pollution caused by air entering underground are solved 100311 In a specific implementing process, in step S102, when the directional pipeline is drilled, an upper segment of the directional pipeline is a vertical pipeline, a lower segment of the directional pipeline is an arc-shaped pipeline, and the vertical pipeline is communicated with a position below the liquid surface of the geothermal well through the arc-shaped pipeline. The vertical pipeline of the upper segment is parallel to the geothermal well 10, so as to ensure that a measuring rope can smoothly detect the position of the liquid surface downward when the measuring rope is used for measuring the liquid level. The directional pipeline is generally a small wellbore with a small diameter that meets the requirements for measuring a water level. 100321 In step S104, ground air can be effectively prevented from entering the geothermal well by sealing both the wellhead of the geothermal well and the upper port of the directional pipeline, so as to avoid oxidation reactions with underground liquids or equipment to cause equipment corrosion and water pollution.

[0033] In step 5106, in a case of monitoring and acquiring the annulus pressure in the geothermal well and the annulus pressure in the directional pipeline, a pressure gauge is arranged in each of the geothermal well and the directional pipeline; and the annulus pressure in the geothermal well and the annulus pressure in the directional pipeline are respectively monitored and acquired through the pressure gauges.

100341 In a process of pumping hot water from the geothermal well, a liquid level and a pressure inside the geothermal well will change. When the hot water is pumped to a certain extent, the liquid level of the geothermal well will be in a stable state, that is, the liquid level will not be changed up and down. In a case that the annulus pressure in the geothermal well is not equal to the annulus pressure in the directional pipeline, in order to ensure the accuracy of monitoring liquid level data, the pressure in the directional pipeline needs to be regulated, so as to balance the pressure in the geothermal well and the pressure in the directional pipeline. Specifically, after the annulus pressure in the geothermal well and the annulus pressure in the directional pipeline are monitored and acquired, if the annulus pressure in the geothermal well is not balanced with the annulus pressure in the directional pipeline, as shown in FIG. 2, the method for measuring a liquid level of a geothermal well of the present embodiment further includes: 100351 S107: the annulus pressure in the directional pipeline is regulated through a pressure regulating device arranged in the directional pipeline; and the annulus pressure in the geothermal well and the annulus pressure in the directional pipeline are repeatedly monitored arid acquired until the annulus pressure in the geothermal well is equal to the annulus pressure in the directional pipeline.

100361 According to a second embodiment of the present disclosure, a method for measuring a liquid level of a geothermal well is provided, as shown in FIG. 3, which specifically includes the following steps: 100371 S202: a directional pipeline which is communicated with a geothermal well is drilled and is adjacent to the geothermal well, and a communication point between the directional pipeline and the geothermal well is located below a liquid surface of the geothermal well; 100381 S204: both a wellhead of the geothermal well and an upper port of the directional pipeline are sealed; and 100391 S206: a part above the liquid surface of the geothermal well is communicated with a part above the liquid surface of the directional pipeline through a communicating pipeline formed between the geothermal well and the directional pipeline, and the liquid level in the directional pipeline is measured to obtain the liquid level in the geothermal well.

100401 The difference between the method for measuring a liquid level of a geothermal well of the present embodiment and Embodiment 1 is that the part above the liquid surface of the geothermal well is communicated with the part above the liquid surface of the directional pipeline through the communicating pipeline, so that the pressure in the geothermal well is equal to the pressure in the directional pipeline at any time. Therefore, the annulus pressure in the geothermal well and the annulus pressure in the directional pipeline do not need to be measured and regulated, and a measurement process is more convenient. In a process of measuring the liquid level of the geothermal well, the geothermal well is communicated with a lower end of the directional pipeline to form a communicating vessel; there is no pipeline or other obstacles in the directional pipeline, which will not affect a normal operation of measurement equipment, thereby ensuring the accuracy of the measured data; and in addition, air can be prevented from entering the geothermal well by measuring the liquid level in the directional pipeline, and equipment corrosion and water pollution are avoided. The problems of distortion of liquid level data acquired in a geothermal well liquid level measurement process in the conventional art and equipment corrosion and water pollution caused by air entering underground are solved.

[0041] According to a third aspect of the present disclosure, a structure for measuring a liquid level of a geothermal well is provided, as shown in FIG. 4, which includes: a geothermal well 10, a directional pipeline 20, and a measurement part 30; the directional pipeline 20 is formed adjacent to the geothermal well 10; a lower end of the directional pipeline 20 is communicated with a part below a liquid surface of the geothermal well 10; and the measurement part 30 is arranged in the directional pipeline 20, and the measurement part 30 is used for measuring the liquid level in the directional pipeline 20 to obtain the liquid level of the geothermal well 10.

[0042] According to the structure for measuring a liquid level of a geothermal well of the present embodiment, the directional pipeline 20 communicated with the geothermal well 10 is formed, the geothermal well 10 and the directional pipeline 20 form the communicating vessel, and the liquid level of the directional pipeline 20 is indirectly measured to obtain the liquid level of the geothermal well 10. There is no pipeline or other obstacles in the directional pipeline, which will not affect a normal operation of the measurement equipment, thereby ensuring the accuracy of the measured data; and in addition, air can be prevented from entering the geothermal well by measuring the liquid level through the directional pipeline, and equipment corrosion and water pollution are avoided. The problems of distortion of liquid level data acquired in a geothermal well liquid level measurement process in the conventional art and equipment corrosion and water pollution caused by air entering underground are solved.

[0043] In a specific implementation process, a water pumping pipeline 80 is arranged in the geothermal well 10, and a submersible pump 90 is arranged at a lower end of the water pumping pipeline 80, thereby continuously pumping hot water to the ground. Both the wellhead of the geothermal well 10 and the upper part of the directional pipeline 20 are sealed. The geothermal well 10 is completely sealed. A sealing cover of the directional pipeline 20 may be opened or closed. A sealed environment in the directional pipeline 20 can be ensured when the upper port of the directional pipeline 20 is closed. The measurement part 30 can be lowered when the liquid level is measured in a case that the upper port of the directional pipeline 20 is opened.

[0044] In a specific implementing process, an upper segment of the directional pipeline 20 is a vertical pipeline, a lower segment of the directional pipeline is an arc-shaped pipeline, and the vertical pipeline is communicated with a position below the liquid surface of the geothermal well 10 through the arc-shaped pipeline. The vertical pipeline of the upper segment is parallel to the geothermal well 10, so as to ensure that a measuring rope can smoothly detect the position of the liquid surface downward when the measuring rope is used for measuring the liquid level. The directional pipeline is generally a small wellbore with a small diameter that meets the requirements for measuring the water level. The structure for measuring a liquid level of a geothermal well of the present embodiment has two different structures. In a first structure for measuring a liquid level of a geothermal well, since the geothermal well 10 is not communicated with the position above the liquid surface of the directional pipeline 20, when hot water is pumped from the geothermal well 10, there will be a deviation between the annulus pressures inside the geothermal well 10 and the directional pipeline 20, resulting in a deviation in the liquid level. In order to ensure the accuracy of monitoring the liquid level, the annulus pressures of the geothermal well 10 and the directional pipeline 20 need to be kept balance. Further, the first structure for measuring a liquid level of a geothermal well further includes a first pressure gauge 40, a second pressure gauge 50, and a pressure regulating device 60. The first pressure gauge 40 is arranged in the geothermal well 10. The first pressure gauge 40 is used for monitoring and acquiring an annulus pressure in the geothermal well 10. The second pressure gauge 50 is arranged in the directional pipeline 20. The second pressure gauge 50 is used for monitoring and acquiring an annulus pressure in the directional pipeline 20. The pressure regulating device 60 is communicated with the directional pipeline 20 and is connected to each of the first pressure gauge 40 and the second pressure gauge 50. When there is a deviation between the pressures monitored by the first pressure gauge 40 and the second pressure gauge 50, and the annulus pressure in the directional pipeline 20 is regulated through the pressure regulating device 60, so that the annulus pressure in the directional pipeline 20 is equal to the annulus pressure in the geothermal well 10. At this moment, the accuracy of monitoring the liquid level can be ensured.

[0045] As shown in FIG. 5, a second structure for measuring a liquid level of a geothermal well includes a communicating pipeline 70. The communicating pipeline 70 is formed between the geothermal well 10 and the directional pipeline 20 to communicate a part above the liquid surface of the geothermal well 10 and a part above the liquid surface of the directional pipeline 20. The annulus pressure of the geothermal well 10 and the annulus pressure of the directional pipeline 20 are kept balance all the time by the communicating pipeline 70; and the accuracy of monitoring the liquid level can be ensured.

100461 Further, when the liquid level is measured actually, the measurement part 30 may be a measuring rope, or may also use a sonic liquid-level meter or other forms of liquid-level meters. [0047] The above is only the preferred embodiments of the present disclosure, and is not intended to limit the present disclosure. For those skilled in the art, the present disclosure may have various modifications and changes. Any modifications, equivalent replacements, improvements and the like made within the spirit and principle of the present disclosure shall fall within the scope of protection of the present disclosure.

Claims

WHAT IS CLAIMED IS: 1. A method for measuring a liquid level of a geothermal well, comprising: drilling a directional pipeline which is communicated with a geothermal well and is adjacent to the geothermal well, a communication point between the directional pipeline and the geothermal well being located below a liquid surface of the geothermal well; sealing both a wellhead of the geothermal well and an upper port of the directional pipeline; respectively monitoring and acquiring an annulus pressure in the geothermal well and an annulus pressure in the directional pipeline in a case that the liquid level of the geothermal well is in a stable state; and measuring a liquid level in the directional pipeline to obtain the liquid level of the geothermal well in a case that the annulus pressure in the geothermal well is equal to the annulus pressure in the directional pipeline.
2. The method for measuring a liquid level of a geothermal well according to claim 1, wherein in a case the annulus pressure in the geothermal well is not equal to the annulus pressure in the directional pipeline, the method further comprises: regulating the annulus pressure in the directional pipeline through a pressure regulating device arranged in the directional pipeline; and repeatedly monitoring and acquiring the annulus pressure in the geothermal well and the annulus pressure in the directional pipeline until the annulus pressure in the geothermal well is equal to the annulus pressure in the directional pipeline.
3. The method for measuring a liquid level of a geothermal well according to claim 1, wherein in a case of monitoring and acquiring the annulus pressure in the geothermal well and the annulus pressure in the directional pipeline, the method further comprises: respectively setting pressure gauges in the geothermal well and the directional pipeline; and respectively monitoring and acquiring the annulus pressure in the geothermal well and the annulus pressure in the directional pipeline through the pressure gauges.
4. A method for measuring a liquid level of a geothermal well, comprising: drilling a directional pipeline which is communicated with a geothermal well and is adjacent to the geothermal well, a communication point between the directional pipeline and the geothermal well being located below a liquid surface of the geothermal well; sealing both a wellhead of the geothermal well and an upper port of the directional pipeline; communicating a part above the liquid surface of the geothermal well and a part above a liquid surface of the directional pipeline through a communicating pipeline formed between the geothermal well and the directional pipeline; and measuring a liquid level in the directional pipeline to obtain the liquid level of the geothermal well.
5. A structure for measuring a liquid level of a geothermal well, comprising: a geothermal well (10); a directional pipeline (20) formed adjacent to the geothermal well (10), a lower end of the directional pipeline (20) being communicated with a part below a liquid surface of the geothermal well (10); and a measurement part (30) arranged in the directional pipeline (20), the measurement part (30) being used for measuring a liquid level in the directional pipeline (20) to obtain the liquid level of the geothermal well (10).
6. The structure for measuring a liquid level of a geothermal well according to claim 5, wherein both a wellhead of the geothermal well (10) and an upper port of the directional pipeline (20) are sealed.
7. The structure for measuring a liquid level of a geothermal well according to claim 6, further comprising: a first pressure gauge (40) arranged in the geothermal well (10), the first pressure gauge (40) being used for monitoring and acquiring an annulus pressure in the geothermal well (10); and a second pressure gauge (50) arranged in the directional pipeline (20), the second pressure gauge (50) being used for monitoring and acquiring an annulus pressure in the directional pipeline (20).
8. The structure for measuring a liquid level of a geothermal well according to claim 7, further comprising: a pressure regulating device (60) communicated with the directional pipeline (20) and connected to each of the first pressure gauge (40) and the second pressure gauge (50), the pressure regulating device (60) being used for regulating the annulus pressure in the directional pipeline (20), so that the annulus pressure in the directional pipeline (20) is equal to the annulus pressure in the geothermal well (10).
9. The structure for measuring a liquid level of a geothermal well according to claim 5, further comprising: a communicating pipeline (70), formed between the geothermal well (10) and the directional pipeline (20) to communicate a part above the liquid surface of the geothermal well and a part above the liquid surface of the directional pipeline.
10. The structure for measuring a liquid level of a geothermal well according to claim 5, wherein the measurement part (30) is a measuring rope.