Shaft temperature measuring device

Abstract

The invention discloses a shaft temperature measuring device which comprises a controller, a collecting part, a balance weight part and a connecting part used for connecting the collecting part and the balance weight part, the collecting part is electrically connected with the controller, an electric control gate is arranged at the bottom of the collecting part, and the electric control gate is electrically connected with the controller. The collecting part is used for measuring and collecting various required data, the position of the strong acid reagent is adjusted through opening and closing of the electric control gate so as to act on the connecting part, the connecting part fails to connect the collecting part and the counterweight part, then the collecting part is separated from the counterweight part, the collecting part is recycled, and the data is obtained. The device has the beneficial effect that the temperature field in the single-well shaft can be accurately measured.

Description

Technical Field

[0001] The invention relates to the technical field of wellbore temperature field measurement, and in particular to a temperature measurement device in single-well coaxial casing geothermal closed-loop mining. Background Art

[0002] Geothermal energy is a renewable energy source that is abundant, relatively inexpensive and widely distributed. Compared with other new energy sources (such as solar energy, wind energy and biomass energy, etc.), geothermal energy has the characteristics of wide distribution, less external influence (such as day and night, wind speed, temperature difference), low carbon emissions and low maintenance costs. The coaxial casing closed cycle heat extraction technology of geothermal wells is a new geothermal development technology suitable for medium and deep geothermal energy. Existing research results show that the insulation structure and high thermal conductivity cement designed in this technology have a positive effect on heat extraction and heating, and have the advantages of high heat exchange efficiency and "heat extraction without water extraction".

[0003] For the exploitation of geothermal resources, the most common method is to directly extract water and heat. However, this method has limitations, and the extraction of groundwater may cause problems such as groundwater level decline and formation collapse. The country advocates the development and utilization of geothermal resources in the way of "extracting heat without taking water", and the single-well coaxial casing closed heat exchange system is very consistent with this initiative. This system realizes "extracting heat without taking water" and can avoid the reinjection restrictions of low-permeability formations and the pollution of groundwater and formations. At the same time, the system mainly exchanges heat through forced convection of formation water, natural convection of the inner tube of the annulus, and heat conduction between the wellbore and the formation. The effect of this heat transfer method is largely better than the effect of heat transfer through soil in the buried heat pump system. In addition, the heat exchange system exchanges heat through the entire area in contact with the formation, and the heat exchange area is much larger than the single-well U-tube underground heat exchange system.

[0004] At present, in the single-well coaxial casing closed heat exchange system, there is a great demand for underground temperature field measurement. However, in the traditional temperature field measurement method, the operation of putting and recovering the measuring device into the well is cumbersome, resulting in a long time, low temperature measurement efficiency, and affecting subsequent mining work. Summary of the invention

[0005] In order to solve the above problems, the present application provides a wellbore temperature measuring device.

[0006] The present application provides a wellbore temperature measurement device that adopts the following technical solution:

[0007] A wellbore temperature measuring device comprises a controller, a collection part, a counterweight part and a connecting part for connecting the collection part and the counterweight part, wherein the collection part is electrically connected to the controller;

[0008] The connecting part comprises an outer sleeve, an inner sleeve and a connecting piece, the diameter of the outer sleeve is larger than the diameter of the inner sleeve, the outer sleeve and the inner sleeve are both fixedly connected to the bottom of the collecting part, and the inner sleeve is located on the inner side of the outer sleeve;

[0009] The top of the counterweight part is fixedly connected with a connecting column, and the connecting column is correspondingly inserted into the inner sleeve, and one end of the outer sleeve away from the collecting part abuts against the top of the counterweight part;

[0010] Two opposite positions on the side wall of the outer sleeve, two opposite positions on the side wall of the inner sleeve and the connecting column are respectively provided with corresponding and communicating mounting holes, and the connecting member passes through the mounting holes and is penetrated on the outer sleeve, the inner sleeve and the connecting column;

[0011] A mounting groove is provided at the bottom of the collection part, and an electric-controlled gate is installed in the mounting groove. The electric-controlled gate is located on one side of the connecting piece and divides the inner cavity of the outer sleeve into a reaction chamber and a storage chamber. The connecting piece is located in the reaction chamber, and strong acid is stored in the storage chamber. The electric-controlled gate is electrically connected to the controller. When the controller controls the electric-controlled gate to open, the electric-controlled gate retracts toward the bottom of the mounting groove, and the strong acid enters the reaction chamber to corrode and dissolve the connecting piece.

[0012] Furthermore, the acquisition part includes a cylindrical mounting frame, a temperature sensor, a CCL positioner and a recording chip, and the temperature sensor, the CCL positioner and the recording chip are all arranged on the cylindrical mounting frame, and the temperature sensor, the CCL positioner and the recording chip are all electrically connected to the controller.

[0013] Furthermore, a direction sensor is also provided on the cylindrical mounting frame, and the direction sensor is electrically connected to the controller.

[0014] Furthermore, a plurality of temperature sensors are provided.

[0015] Furthermore, the counterweight part is cylindrical, and the central axis of the counterweight part coincides with the central axis of the cylindrical mounting frame.

[0016] Furthermore, the central axis of the outer sleeve and the central axis of the inner sleeve both coincide with the central axis of the cylindrical mounting frame, and the central axis of the connecting column coincides with the central axis of the counterweight part.

[0017] Furthermore, a wellbore temperature measurement method based on the wellbore temperature measurement device comprises the following steps:

[0018] S1 well selection: manually selecting wells according to the historical information of each well, and selecting the well to be tested; S2 setting preset parameter values: based on the historical information of the well to be tested, the wellbore temperature measuring device sets the double parameters of well depth and test time respectively;

[0019] S3: performing actions before temperature measurement: opening the wellhead of the well to be measured and inserting the wellbore temperature measuring device;

[0020] S4 starts temperature measurement: when the wellbore temperature measuring device enters the well, the well depth is measured in real time through the CCL locator coupling, and the temperature sensor is used to measure the temperature of the current well depth where the wellbore temperature measuring device is located, and the temperature data and the well depth data are written into the recording chip based on the corresponding time;

[0021] S5: Recovering the collection part: When the wellbore temperature measuring device reaches a predetermined depth underground, the controller controls the electric control gate to open, so that the strong acid enters the second chamber to contact and dissolve the connector, until the part of the connector that passes through the inner casing and the connecting column is completely dissolved, the connecting column is separated from the inner casing, and the collection part floats up due to the buoyancy, and is recovered at the wellhead; S6: After recovery, the recording chip is read to obtain relevant data and analyze it.

[0022] Furthermore, the step S5 also includes that when the wellbore temperature measuring device reaches a predetermined time underground, the controller controls the electric-controlled gate to open.

[0023] In summary, the present application includes at least one of the following beneficial technical effects:

[0024] The present invention can effectively measure the temperature field in a single well, can complete the sinking and floating in the wellbore through a two-stage structure, record the data in the downward process through the sensor of the acquisition part and the CCL positioning algorithm, and ensure that the whole device can be lowered to the bottom of the well through the counterweight part to ensure the accurate measurement of the temperature field in the wellbore of a single well. In addition, the temperature measuring device is easy to "put in" and "recover" when in use, and does not require mechanical salvage during recovery, which is conducive to saving time. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of a wellbore temperature measurement device in an embodiment of the present application.

[0026] Figure 2 It is a schematic diagram of the position of the electric-controlled gate in the embodiment of the present application.

[0027] Figure 3 It is a structural schematic diagram of the counterweight part in the embodiment of the present application.

[0028] Figure 4 It is a schematic diagram used to reflect the electrical connection relationship between the controller and the electric-controlled gate in the embodiment of the present application.

[0029] Figure 5 It is a structural diagram used to reflect the collection part in the embodiment of the present application.

[0030] Description of reference numerals:

[0031] 1. Collection part; 101. Cylindrical mounting frame; 102. CCL positioner; 103. Recording chip; 104. Temperature sensor; 105. Direction sensor; 2. Counterweight part; 3. Outer sleeve; 4. Inner sleeve; 5. Connector; 6. Connecting column; 7. Mounting hole; 8. Electric control gate; 9. Reaction chamber; 10. Storage chamber. DETAILED DESCRIPTION

[0032] The following is combined with Figure 1-5 This application is described in further detail.

[0033] There are many schemes for the development of deep geothermal energy, mainly including open-loop mining methods and closed-loop mining methods. The main difference is whether the heat exchange medium is mixed with the formation liquid. In the closed-loop mining method, since the heat exchange medium is water injected into the wellbore from the ground and is not mixed with the formation liquid, the liquid is not mixed and then heated, but the water in the wellbore is circulated in a single well to obtain the bottom heat, only taking heat without taking formation water, so the downhole temperature field can help to explore the downhole temperature and development potential. Therefore, the single-well "heat without water" method requires a clear understanding of the downhole temperature field to fully develop.

[0034] In order to accurately and effectively measure the temperature field in a single well, an embodiment of the present application discloses a wellbore temperature measurement device.

[0035] Reference Figures 1 to 4 A wellbore temperature measuring device includes a controller, a collection part 1, a counterweight part 2 and a connecting part for connecting the collection part 1 and the counterweight part 2, and the collection part 1 is electrically connected to the controller.

[0036] Reference Figure 1 , Figure 4 and Figure 5In order to effectively and accurately measure the downhole temperature, the acquisition part 1 includes a cylindrical mounting frame 101, a CCL positioner 102, a recording chip 103 and a plurality of temperature sensors 104. Among them, the CCL positioner 102 is used to measure the depth in real time through the coupling, the temperature sensor 104 is used to measure the temperature of the current well depth of the device; the recording chip 103 is used to record the time, various data and the opening and closing state of the electric control gate 8. The temperature sensor 104, the CCL positioner 102 and the recording chip 103 are all arranged on the cylindrical mounting frame 101, and the temperature sensor 104, the CCL positioner 102 and the recording chip 103 are all electrically connected to the controller. In addition, in order to more accurately determine the movement direction of the device, distinguish the deep-diving process and the return process of the device, and conduct further verification to improve the accuracy of the measurement, a direction sensor 105 is also arranged on the cylindrical mounting frame 101, and the direction sensor 105 is electrically connected to the controller.

[0037] Reference Figure 1 and Figure 2 The connecting part includes an outer sleeve 3, an inner sleeve 4 and a connecting piece 5. The diameter of the outer sleeve 3 is larger than the diameter of the inner sleeve 4. The outer sleeve 3 and the inner sleeve 4 are both fixedly connected to the bottom of the cylindrical mounting frame 101. The inner sleeve 4 is located on the inner side of the outer sleeve 3. The central axis of the outer sleeve 3 and the central axis of the inner sleeve 4 both coincide with the central axis of the cylindrical mounting frame 101. The connecting piece 5 is specifically a connecting rod.

[0038] Reference Figure 1 and Figure 3 The counterweight part 2 is cylindrical in shape, and a connecting column 6 is fixedly connected to the top of the counterweight part 2. The central axis of the connecting column 6 coincides with the central axis of the counterweight part 2. The connecting column 6 is correspondingly inserted in the inner sleeve 4. The central axis of the counterweight part 2 coincides with the central axis of the cylindrical mounting frame 101, and the end of the outer sleeve 3 away from the cylindrical mounting frame 101 abuts against the top of the counterweight part 2.

[0039] Reference Figure 1 , Figure 2 and Figure 3 Two opposite positions on the side wall of the outer sleeve 3, two opposite positions on the side wall of the inner sleeve 4 and the connecting column 6 are each provided with corresponding mounting holes 7, and the connecting member 5 passes through the mounting holes 7 and is inserted into the outer sleeve 3, the inner sleeve 4 and the connecting column 6.

[0040] Reference Figures 1 to 5, the bottom of the collection part 1 is provided with two mounting grooves, the two mounting grooves are located on both sides of the connecting piece 5, and an electric control gate 8 is correspondingly installed in each mounting groove, the two electric control gates 8 are located on both sides of the connecting piece 5, and the inner cavity of the outer sleeve 3 is divided into a reaction chamber 9 and two storage chambers 10, the connecting piece 5 is located in the reaction chamber 9, and the two storage chambers 10 are pre-stored with strong acid, and the two electric control gates 8 are electrically connected to the controller. The staff can set the controller according to the actual situation, so that the controller controls one or two electric control gates 8 to open (and / or close). When the electric control gate 8 is in a closed state, the end of the electric control gate 8 away from the collection part 1 is pressed against the top of the counterweight part 2. When the electric control gate 8 receives the opening signal sent by the controller, the electric control gate 8 moves toward the bottom of the mounting groove, retracts into the mounting groove, and the strong acid enters the reaction chamber 9, contacts and corrodes and dissolves the connecting piece 5.

[0041] Based on the above-mentioned wellbore temperature measuring device, the present application embodiment also discloses a wellbore temperature measuring method, referring to Figures 1 to 5 , the measurement method specifically includes the following steps:

[0042] S1 Well selection: Manual well selection is performed based on the basic information of each well, and the wells to be tested are selected from them. Specifically, the first step is to select abandoned wells for geothermal exploitation, and the second step is to select wells with better total temperature fields in the past production history from the abandoned wells. Both are rough selection.

[0043] S2 sets the preset parameter values ​​for the measuring device: based on the basic information of the well to be measured, the well depth and test time are set respectively. Specifically, the basic information refers to various aspects of the well to be measured, such as: CCL measures the depth by the number of couplings, and can determine the number of couplings by the number of pipe strings, and then determine the approximate downhole position, well inclination, casing damage and casing change, etc., so as to judge whether it will affect the downhole development equipment, calculate the development cost, etc.

[0044] S3 Actions to be performed before temperature measurement: Open the wellhead of the well to be measured and put into the wellbore temperature measuring device.

[0045] S4 starts temperature measurement: When the wellbore temperature measurement device enters the well, the well depth is measured in real time through the CCL locator 102 coupling, and the temperature sensor 104 measures the temperature of the current well depth where the wellbore temperature measurement device is located, and writes the temperature data into the recording chip 103 based on the corresponding well depth. Specifically, at the beginning of the measurement process, as the device is continuously lowered into the well, under the control of the controller, each sensor detects and feeds back relevant data, and the controller writes the received relevant data into the recording chip 103 accordingly. Among them, the relevant data includes time, well depth, temperature and other data; the well depth is assisted by the CCL locator 102, and the direction sensor 105 can more accurately determine the exact direction of the device during the downward process, and determine the calculation of the final inclination and vertical depth; the temperature is detected and fed back by the temperature sensor 104.

[0046] S5 Recover the collection part 1: When the wellbore temperature measuring device reaches a predetermined depth or time in the well, the controller controls the driving mechanism to open the electric control gate 8, so that the strong acid contacts and dissolves the connector 5, until the part of the connector 5 that penetrates the inner casing 4 and the connecting column 6 is completely dissolved, the connecting column 6 is separated from the inner casing 4, and the collection part 1 is floated up by the buoyancy, and recovered at the wellhead, and the counterweight part 2 is left in the well by the gravity. In practice, in order to achieve this step, the strong acid can be selected from dilute sulfuric acid. In order not to be dissolved or corroded by dilute sulfuric acid, the materials of the cylindrical mounting frame 101, the outer casing 3, and the inner casing 4 all need to be selected from materials with good strong acid resistance. For example, the materials of the cylindrical mounting frame 101, the outer casing 3, and the inner casing 4 can be selected from stainless steel, especially chromium-nickel austenitic stainless steel and duplex stainless steel pipes containing molybdenum, copper, and silicon (3% to 4%) have better sulfuric acid resistance. In order to facilitate the dissolution of the connector 5 by dilute sulfuric acid, the material of the connector 5 can be selected from active metals, such as magnesium, iron, etc. For example, dilute sulfuric acid is selected as a strong acid, and magnesium is selected as the material of the connector 5, and the connector 5 is dissolved by utilizing the substitution reaction between dilute sulfuric acid and magnesium.

[0047] S6 Data acquisition and analysis: After recovery, disassemble the collection part 1 to take out the chip, read the recording chip 103, obtain relevant data and analyze it.

[0048] The implementation principle of a wellbore temperature measurement device in the embodiment of the present application is:

[0049] In practical applications, the wellbore temperature measuring device described in the present application connects the two structures of the collection part 1 and the counterweight part 2 together through the connector 5, so that it can continuously descend in the well and measure relevant data such as time, well depth and temperature. After the temperature measurement work is completed, the collection part 1 and the counterweight part 2 can be separated again, thereby changing into a "double-stage structure" to complete sinking and floating in the wellbore respectively. The temperature measuring device is convenient to "put in" and "recover" when in use, and no mechanical salvage is required during recovery, which is conducive to saving time.

[0050] The temperature sensor 104, the direction sensor 105 and the CCL positioner 102 of the acquisition part 1 are used to record the relevant data in the downward process, and the gravity of the counterweight part 2 ensures that the measuring device as a whole can be lowered to the bottom of the well to ensure the accurate measurement of the temperature field in the wellbore of a single well. In summary, the present invention has the advantages of simple operation, efficient measurement and accurate data, which can save development costs and improve economic benefits.

[0051] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A wellbore temperature measuring device, characterized in that: It comprises a controller, a collection part (1), a counterweight part (2) and a connecting part for connecting the collection part (1) and the counterweight part (2), wherein the collection part (1) is electrically connected to the controller; The connecting part comprises an outer sleeve (3), an inner sleeve (4) and a connecting piece (5); the diameter of the outer sleeve (3) is larger than the diameter of the inner sleeve (4); the outer sleeve (3) and the inner sleeve (4) are both fixedly connected to the bottom of the collecting part (1); and the inner sleeve (4) is located on the inner side of the outer sleeve (3); The top of the counterweight part (2) is fixedly connected with a connecting column (6), and the connecting column (6) is correspondingly inserted into the inner sleeve (4), and one end of the outer sleeve (3) away from the collecting part (1) abuts against the top of the counterweight part (2); Two opposite positions on the side wall of the outer sleeve (3), two opposite positions on the side wall of the inner sleeve (4) and the connecting column (6) are respectively provided with corresponding and communicating mounting holes (7); the connecting member (5) passes through the mounting holes (7) and is penetrated on the outer sleeve (3), the inner sleeve (4) and the connecting column (6); The bottom of the collecting part (1) is provided with a mounting groove, in which an electric-controlled gate (8) is installed. The electric-controlled gate (8) is located on one side of the connecting piece (5) and divides the inner cavity of the outer sleeve (3) into a reaction chamber (9) and a storage chamber (10). The connecting piece (5) is located in the reaction chamber (9), and a strong acid is stored in the storage chamber (10). The electric-controlled gate (8) is electrically connected to the controller. When the controller controls the electric-controlled gate (8) to open, the electric-controlled gate (8) retracts toward the bottom of the mounting groove, and the strong acid enters the reaction chamber (9) to corrode and dissolve the connecting piece (5).

2. A wellbore temperature measuring device according to claim 1, characterized in that: The collecting part (1) comprises a cylindrical mounting frame (101), a temperature sensor (104), a CCL positioner (102) and a recording chip (103); the temperature sensor (104), the CCL positioner (102) and the recording chip (103) are all arranged on the cylindrical mounting frame (101); and the temperature sensor (104), the CCL positioner (102) and the recording chip (103) are all electrically connected to the controller.

3. A wellbore temperature measuring device according to claim 2, characterized in that: The cylindrical mounting frame (101) is also provided with a direction sensor (105), and the direction sensor (105) is electrically connected to the controller.

4. A wellbore temperature measuring device according to claim 2, characterized in that: A plurality of temperature sensors (104) are provided.

5. A wellbore temperature measuring device according to claim 1, characterized in that: The counterweight part (2) is cylindrical in shape, and the central axis of the counterweight part (2) coincides with the central axis of the cylindrical mounting frame (101).

6. A wellbore temperature measuring device according to claim 1, characterized in that: The central axis of the outer sleeve (3) and the central axis of the inner sleeve (4) both coincide with the central axis of the cylindrical mounting frame (101), and the central axis of the connecting column (6) coincides with the central axis of the counterweight part (2).

7. A wellbore temperature measuring device according to claim 1, characterized in that: A wellbore temperature measurement method based on the wellbore temperature measurement device comprises the following steps: S1 well selection: manually selecting wells according to the historical information of each well, and selecting the well to be tested; S2 setting preset parameter values: based on the historical information of the well to be tested, the wellbore temperature measuring device sets the double parameters of well depth and test time respectively; S3: performing actions before temperature measurement: opening the wellhead of the well to be measured and inserting the wellbore temperature measuring device; S4 starts temperature measurement: when the wellbore temperature measurement device enters the well, the well depth is measured in real time through the CCL positioner (102) coupling, and the temperature sensor (104) measures the temperature of the current well depth where the wellbore temperature measurement device is located, and writes the temperature data and the well depth data into the recording chip (103) based on the corresponding time; S5: recovering the collection part (1): when the wellbore temperature measuring device reaches a predetermined depth in the well, the controller controls the electric control gate (8) to open, so that the strong acid enters the reaction chamber (9) to contact and dissolve the connector (5), until the part of the connector (5) that penetrates the inner casing (4) and the connecting column (6) is completely dissolved, the connecting column (6) is separated from the inner casing (4), and the collection part (1) floats up due to the buoyancy, and is recovered at the wellhead; S6 Data acquisition and analysis: After recovery, the recording chip (103) is read to acquire relevant data and perform analysis.

8. A wellbore temperature measuring device according to claim 7, characterized in that: The step S5 also includes that when the wellbore temperature measuring device reaches a predetermined time in the well, the controller controls the electric control gate (8) to open.

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