Carbon dioxide saturation monitoring device and method based on optical fiber-active heating method

Abstract

The invention discloses a carbon dioxide saturation monitoring device and method based on an optical fiber-active heating method.The carbon dioxide saturation monitoring device based on the optical fiber-active heating method comprises a heating system, a temperature collecting system and a monitoring system, and the monitoring system is buried in the drilling position of a rock mass; the monitoring system is electrically connected with the heating system and the monitoring system. According to the carbon dioxide saturation monitoring device based on the optical fiber-active heating method, the monitoring device is arranged in a deep well, the high-precision temperature collection function of the DTS demodulator is combined, continuous monitoring of the temperature change of a target stratum is achieved, the change of the carbon dioxide saturation of the target stratum is calculated, and the carbon dioxide saturation monitoring accuracy is improved. And technical support is provided for geological sequestration.

Description

Technical Field

[0001] The present invention relates to the technical field of geological monitoring, and in particular to a device and method for monitoring carbon dioxide saturation based on an optical fiber-active heating method. Background Art

[0002] At present, in CO2 geological storage projects, the distribution of CO2 in the reservoir is usually reflected by monitoring its saturation. However, since the injection depth is usually large, accurately monitoring the saturation of CO2 becomes a very challenging task. Fiber optic monitoring technology, with its extremely high sensitivity and real-time performance, can effectively reflect the changes in temperature, strain and vibration in the external environment, and has therefore been widely used in the monitoring field.

[0003] After carbon dioxide is injected into the reservoir, it will significantly change the thermal conductivity of the rock mass by displacing the pore water in the rock mass. Based on this principle, how to establish a quantitative relationship between temperature, time, thermal conductivity of the rock mass medium and carbon dioxide saturation through active heating methods combined with thermodynamic theory, and how to monitor carbon dioxide saturation through this quantitative relationship is a technical problem that needs to be solved urgently. Summary of the invention

[0004] In view of the above problems, the present invention is proposed to provide a device and method for monitoring carbon dioxide saturation based on an optical fiber-active heating method, which overcomes the above problems or at least partially solves the above problems.

[0005] Other features and advantages of the present invention will become apparent from the following detailed description, or may be learned in part by practice of the present invention.

[0006] According to a first aspect of an embodiment of the present invention, a carbon dioxide saturation monitoring device based on an optical fiber-active heating method is provided, the carbon dioxide saturation monitoring device based on an optical fiber-active heating method comprising: a heating system, a temperature acquisition system and a monitoring system, the monitoring system is buried at a drilling position of a rock mass, the monitoring system is electrically connected to the heating system and the monitoring system respectively; the monitoring system is used to generate a target environment by an optical fiber-active heating method, the heating system is used to provide the monitoring system with electric energy required for heating, and the temperature acquisition system is used to obtain temperature data from the monitoring system; The monitoring system includes a line integration box and a monitoring tube. The monitoring tube is buried at the drilling position of the rock mass. The upper end of the monitoring tube is connected to the line integration box. The line integration box is located outside the rock mass. The line integration box is respectively connected to the monitoring tube and the heating system, and is connected to the monitoring tube and the temperature acquisition system. Among them, the line integration box at least includes an electric heating connection port and a temperature data transmission port. The electric heating connection port is electrically connected to the heating system, and the temperature data transmission port is connected to the temperature acquisition system.

[0007] In some embodiments of the present invention, the carbon dioxide saturation monitoring device based on the fiber-optic - active heating method further includes a terminal. The terminal is connected to the temperature acquisition system and is used to determine the carbon dioxide saturation data of the target formation according to the temperature data obtained by the temperature acquisition system.

[0008] In some embodiments of the present invention, a receiving cavity is hollowed out between the inner wall and the outer wall of the monitoring tube, and a plurality of sensors are respectively and evenly spaced in the receiving cavity.

[0009] In some embodiments of the present invention, the diameter of the outer wall matches the inner diameter of the drill hole.

[0010] In some embodiments of the present invention, the sensor includes a steel pipe, a flange, a heating resistance wire, and a temperature measurement optical cable. The steel pipe is a hollow cylindrical structure. Flanges are respectively arranged at both ends of the steel pipe, and the heating resistance wire and the temperature measurement optical cable respectively pass through the flanges. The heating resistance wire is electrically connected to the heating system through the electric heating connection port.

[0011] In some embodiments of the present invention, the heating system includes a power supply, a voltage regulator, and an electric wire. The voltage regulator is electrically connected to the power supply and the electric heating connection port respectively through the electric wire.

[0012] In some embodiments of the present invention, a control switch is arranged on the electric wire between the power supply and the voltage regulator.

[0013] In some embodiments of the present invention, the temperature acquisition system includes a DTS demodulator and a jumper wire. The DTS demodulator is electrically connected to the temperature data transmission port through the jumper wire.

[0014] According to the second aspect of the embodiments of the present invention, a carbon dioxide saturation monitoring device based on the fiber-optic - active heating method is provided, including the following steps: S1. Arrange the monitoring system at the designated drilling position, and connect the connection ports corresponding to the heating resistance wire and the temperature measurement optical cable in the line integration box, that is, the electric heating connection port and the temperature data transmission port, to the heating system and the temperature acquisition system respectively; S2. Before the heating system works, read the initial data through the temperature acquisition system to confirm that the heating system and the temperature acquisition system are in normal working states; start the power supply, control switch, and voltage regulator of the heating system in sequence to continuously heat the heating resistance wire, and record the heating time at the same time; read the temperature data of the temperature acquisition system in real time through the DTS demodulator; after the heating time reaches the set time, turn off the power supply, control switch, and voltage regulator to stop heating the heating resistance wire, and save the temperature data read by the DTS demodulator. S3. Determine the target formation carbon dioxide saturation data according to the temperature data.

[0015] In some embodiments of the present invention, in step S3, the determining the target formation carbon dioxide saturation data according to the temperature data includes: According to the temperature change Δ T and the logarithm of the set heating time ln t of the linear relationship: to calculate the thermal conductivity λ of the geotechnical medium, where t is the set heating time, Δ T is the change in temperature data within the set heating time t, q is the heat transferred by the heating resistance wire per unit length per unit time, λ is the thermal conductivity of the geotechnical medium, M is a constant; According to the quantitative relationship between the thermal conductivity λ of the geotechnical medium and the water saturation S w of the rock mass, calculate and determine the water saturation S w of the rock mass and the saturation of carbon dioxide 1 - S w .

[0016] The technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages: The carbon dioxide saturation monitoring device and method based on the optical fiber - active heating method in the embodiments of the present invention. The carbon dioxide saturation monitoring device based on the optical fiber - active heating method in the embodiments of the present invention realizes continuous monitoring of the temperature change of the target formation by arranging the monitoring device in a deep well and combining the high - precision temperature acquisition function of the DTS demodulator, and calculates the change of the carbon dioxide saturation of the target formation, providing technical support for geological sequestration.

[0017] The above description is only an overview of the technical solutions of the present invention. In order to be able to understand the technical means of the present invention more clearly, it can be implemented according to the content of the description. And in order to make the above - mentioned and other purposes, features, and advantages of the present invention more obvious and understandable, the following specifically describes the embodiments of the present invention. Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings required for use in the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0019] Figure 1 It is a schematic diagram of the principle structure of a carbon dioxide saturation monitoring device based on the fiber optic - active heating method provided by an embodiment of the present invention; Figure 2 It is a schematic longitudinal sectional view of the monitoring system in an embodiment of the present invention; Figure 3 It is a schematic diagram of the sensor in an embodiment of the present invention; Figure 4 It is a flowchart of a carbon dioxide saturation monitoring method based on the fiber optic - active heating method provided by an embodiment of the present invention.

[0020] Description of the Reference Numerals: 1. Heating system; 2. Temperature acquisition system; 3. Monitoring system; 4. Voltage regulator; 5. Control switch; 6. Power supply; 7. Electric wire; 8. DTS demodulator; 9. Jumper wire; 10. Line integration box; 11. Sensor; 12. Outer wall; 13. Inner wall; 14. Heating resistance wire; 15. Temperature - measuring optical cable; 16. Flange; 17. Steel pipe; 18. Terminal. Detailed Embodiments

[0021] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings.

[0022] Various structural schematic diagrams according to the embodiments of the present disclosure are shown in the drawings. These figures are not drawn to scale. For the purpose of clear expression, some details are enlarged and some details may be omitted. The shapes of various regions and layers shown in the figures, as well as their relative sizes and positional relationships, are only exemplary. In practice, there may be deviations due to manufacturing tolerances or technical limitations, and those skilled in the art can design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0023] In the context of the present disclosure, when a layer / component is referred to as being "on" another layer / component, the layer / component can be directly on the other layer / component, or there can be an intermediate layer / component between them. Additionally, if a layer / component is "on" another layer / component in one orientation, then when the orientation is reversed, the layer / component can be "under" the other layer / component. In the context of the present disclosure, similar or identical components may be denoted by the same or similar reference numerals.

[0024] To better understand the above technical solutions, the following will detail the above technical solutions in combination with specific embodiments. It should be understood that the embodiments of the present disclosure and the specific features in the embodiments are detailed descriptions of the technical solutions of the present invention, rather than limitations on the technical solutions of the present invention. Without conflict, the technical features in the embodiments of the present invention and the embodiments can be combined with each other.

[0025] Figure 1 The principle structural schematic diagram of a carbon dioxide saturation monitoring device based on the optical fiber - active heating method provided by an embodiment of the present invention is as Figure 1 shown. The carbon dioxide saturation monitoring device based on the optical fiber - active heating method includes: a heating system 1, a temperature acquisition system 2, and a monitoring system 3. The monitoring system 3 is buried at the drilling position of the rock mass. The monitoring system 3 is electrically connected to the heating system 1 and the monitoring system 3 respectively. The monitoring system 3 is used to generate a target environment through the optical fiber - active heating method. The target environment is the working environment for monitoring the carbon dioxide saturation of the target formation, so as to establish a quantitative relationship between temperature, time, the thermal conductivity of the rock and soil medium, and carbon dioxide saturation. The heating system 1 is used to provide the electrical energy required for heating for the monitoring system 3. The temperature acquisition system 2 is used to obtain temperature data from the monitoring system 3. Combined with Figure 2 shown, Figure 2 is the longitudinal sectional schematic diagram of the monitoring system 3 in the embodiment of the present invention. The monitoring system 3 includes a line integration box 10 and a monitoring tube. The monitoring tube is buried at the drilling position of the rock mass. The upper end of the monitoring tube is connected to the line integration box 10. The line integration box 10 is located outside the rock mass. The line integration box 10 is used to integrate each line and provide the function of connection ports. The line integration box 10 is respectively connected to the monitoring tube and the heating system 1, and connected to the monitoring tube and the temperature acquisition system 2. Among them, the line integration box 10 at least includes an electric heating connection port and a temperature data transmission port. The electric heating connection port is electrically connected to the heating system 1, and the temperature data transmission port is connected to the temperature acquisition system 2.

[0026] A receiving cavity is hollowed out between the inner wall 13 and the outer wall 12 of the monitoring tube. A plurality of sensors 11 are evenly spaced in the receiving cavity. The receiving cavity formed by the inner wall 13 and the outer wall 12 serves to place and fix the sensors 11, preventing the sensors 11 from deforming or displacing. The sensors 11 are evenly spaced to take into account temperature sensing and acquisition in all directions, improving the accuracy of data. The number of sensors 11 can be selected according to actual application requirements. For example, in the embodiment of the present invention, the number of sensors 11 is 4. In other embodiments of the present invention, the number of sensors 11 can also be 3, 5 or other numbers.

[0027] Combined Figure 3 as shown Figure 3 is a schematic diagram of the sensor 11 in the embodiment of the present invention. The sensor 11 includes a steel pipe 17, a flange 16, a heating resistance wire 14 and a temperature measuring optical cable 15. The steel pipe 17 is a hollow cylindrical structure. The flanges 16 are respectively provided at both ends of the steel pipe 17. The heating resistance wire 14 and the temperature measuring optical cable 15 are respectively passed through the flanges 16. The flange 16 is used to fix the heating resistance wire 14 and the temperature measuring optical cable 15 to prevent their relative movement. The steel pipe 17 wraps the heating resistance wire 14, the temperature measuring optical cable 15 and the flange 16, providing additional mechanical protection and enhancing the overall structural strength. The heating resistance wire 14 is electrically connected to the heating system 1 through the electric heating connection port. The heating resistance wire 14 plays an active heating role. The temperature measuring optical cable 15 is electrically connected to the temperature acquisition system 2. The temperature measuring optical cable 15 is used to sense the temperature information of the surrounding environment.

[0028] The heating system 1 includes a power supply 6, a voltage regulator 4, a control switch 5 and a wire 7. The voltage regulator 4 is electrically connected to the power supply 6 and the electric heating connection port respectively through the wire 7. A control switch 5 is provided on the wire 7 between the power supply 6 and the voltage regulator 4. Among them, the power supply 6 provides energy for heating the heating resistance wire 14 in the monitoring system 3. The voltage regulator 4 can control the output of the power supply 6 to achieve different power heating conditions, so as to adapt to different monitoring requirements. The control switch 5 is used to control the start and stop of the heating process.

[0029] The temperature acquisition system 2 includes a DTS demodulator 8 and a jumper 9. The DTS demodulator 8 is electrically connected to the line integration box 10 through the jumper 9. The jumper 9 is electrically connected to the temperature measuring optical cable 15 through the temperature data transmission port. The jumper 9 is used to transmit the optical information of the temperature acquisition system 2 and the monitoring system 3. The DTS demodulator 8 is used to obtain the temperature information collected by the temperature measuring optical cable 15.

[0030] Specifically, in the embodiment of the present invention, the monitoring system 3 is arranged at a designated drilling position. The diameter of the outer wall 12 matches the inner diameter of the drilling. For example, the inner diameter of the drilling is 140 mm, and the diameter of the outer wall 12 can be selected as 140 mm, ensuring that the outer wall 12 of the monitoring system 3 is in close contact with the surrounding rock mass of the drilling and stabilizing the entire monitoring system 3. Subsequently, the corresponding connection ports of the heating resistance wire 14 and the temperature measurement optical cable 15 in the line integration box 10, namely the electric heating connection port and the temperature data transmission port, are respectively connected to the heating system 1 and the temperature acquisition system 2.

[0031] Before the heating system 1 operates, initial data is read through the temperature acquisition system 2 to confirm that the heating system 1 and the temperature acquisition system 2 are in a normal operating state. The power supply 6, control switch 5, and voltage regulator 4 of the heating system 1 are started in sequence to continuously heat the heating resistance wire 14, and the heating time is recorded simultaneously. The temperature data of the temperature acquisition system 2 is read in real time through the DTS demodulator 8. After the heating time reaches the set time, the power supply 6, control switch 5, and voltage regulator 4 are turned off to stop heating the heating resistance wire 14, and the temperature data read by the DTS demodulator 8 is saved.

[0032] In the embodiment of the present invention, the carbon dioxide saturation monitoring device based on the fiber-optic active heating method may further include a terminal 18. The terminal 18 is connected to the temperature acquisition system 2 and is used to determine the target formation carbon dioxide saturation data according to the temperature data obtained by the temperature acquisition system 2. The terminal 18 is, for example, a terminal device with computing functions such as a PC, server, or smart phone, etc.; specifically, in the embodiment of the present invention, according to the linear relationship between the temperature change amount ΔT and the logarithm of the set heating time ln t : The thermal conductivity λ of the geotechnical medium can be calculated. Among them, the set heating time t can be recorded by the terminal 18, stopwatch, or other devices with timing functions. Δ T is obtained through the temperature acquisition system 2, that is, the change amount of the temperature data within the set heating time t. q is the heat transmitted by the heating resistance wire 14 per unit length per unit time. λ is the thermal conductivity of the geotechnical medium, and M is a constant related to the properties of the geotechnical medium, which can be obtained in advance. Under the condition of constant heating power, λ can be calculated through the slope of the Δ T -ln t straight line. Combining the quantitative relationship between the thermal conductivity λ of the geotechnical medium calibrated in the laboratory test and the water saturation Sw of the rock mass, the terminal 18 can determine the water saturation S w of the rock mass and the saturation of carbon dioxide 1 - S w (assuming that the pores are completely filled with water and carbon dioxide).

[0033] In other embodiments of the present invention, if it is inconvenient to use the terminal 18 in an application scenario such as outdoors, the terminal 18 can be omitted, and the target formation carbon dioxide saturation data can be directly determined by manual calculation based on the collected parameters through the linear relationship between the temperature change ΔT and the logarithm of the set heating time lnt as above.

[0034] The carbon dioxide saturation monitoring device based on the optical fiber-active heating method described in the embodiment of the present invention realizes continuous monitoring of temperature changes of the target formation by deploying the monitoring device in the deep well, and infers the change of carbon dioxide saturation of the target formation, thereby providing technical support for geological storage; the heating system 1 provides energy for the heating resistance wire 14, and can flexibly adjust the heating time and power according to the needs of different target formations to ensure the scientificity and rationality of the monitoring results; through the reasonable design and arrangement of the flange 16, the inner wall 13 and the outer wall 12, the heating resistance wire 14 and the temperature measuring The optical cable 15 can remain stable in the deep well and is not disturbed by external strain, so as to reliably capture the temperature information of the target formation; the layout direction of the sensor 11 covers multiple different directions, which is helpful to obtain more comprehensive monitoring data, facilitate the analysis and comparison of the distribution of carbon dioxide in different directions, and improve the accuracy and comprehensiveness of the monitoring results; in addition, the distance between the heating resistance wire 14, the temperature measuring optical cable 15 and the target formation is extremely small, so that the temperature changes of the three remain highly consistent; the temperature information obtained by the temperature measuring optical cable 15 can accurately reflect the actual environmental changes of the target formation, thereby ensuring the authenticity and reliability of the monitoring.

[0035] Based on the above embodiments, the present invention further provides a method for monitoring carbon dioxide saturation based on optical fiber-active heating method, which is applied to any embodiment of the above-mentioned carbon dioxide saturation monitoring device based on optical fiber-active heating method, see Figure 4 As shown, the carbon dioxide saturation monitoring method based on optical fiber-active heating method includes the following steps: S1, the monitoring system 3 is arranged at the designated drilling position, and the connection ports corresponding to the heating resistance wire 14 and the temperature measuring optical cable 15 in the line integration box 10, i.e., the electric heating connection port and the temperature data transmission port are connected to the heating system 1 and the temperature acquisition system 2 respectively; S2. Before the heating system 1 operates, read the initial data through the temperature acquisition system 2 to confirm that the heating system 1 and the temperature acquisition system 2 are in normal operating states; start the power supply 6, control switch 5, and voltage regulator 4 of the heating system 1 in sequence to continuously heat the heating resistance wire 14, and record the heating time simultaneously; read the temperature data of the temperature acquisition system 2 in real time through the DTS demodulator 8; after the heating time reaches the set time, turn off the power supply 6, control switch 5, and voltage regulator 4 to stop heating the heating resistance wire 14, and save the temperature data read by the DTS demodulator 8; S3. Determine the carbon dioxide saturation data of the target formation according to the temperature data.

[0036] In the embodiment of the present invention, in step S3, the determining the carbon dioxide saturation data of the target formation according to the temperature data includes: According to the temperature change Δ T and the logarithmic relationship with the set heating time ln t of the linear relationship: to calculate the thermal conductivity λ of the geotechnical medium, where t is the set heating time, Δ T is the change in temperature data within the set heating time t, q is the heat transferred by the heating resistance wire per unit length per unit time, λ is the thermal conductivity of the geotechnical medium, M is a constant related to the properties of the geotechnical medium; According to the quantitative relationship between the thermal conductivity λ of the geotechnical medium and the water saturation S w of the rock mass, calculate and determine the water saturation S w of the rock mass and the carbon dioxide saturation 1 - S w .

[0037] The carbon dioxide saturation monitoring device based on the optical fiber - active heating method described in the above embodiment can execute the carbon dioxide saturation monitoring method based on the optical fiber - active heating method provided by the embodiment of the present invention. The carbon dioxide saturation monitoring method based on the optical fiber - active heating method has the corresponding functional components and beneficial effects of the carbon dioxide saturation monitoring device based on the optical fiber - active heating method described in the above embodiment. For details, please refer to the embodiment of the carbon dioxide saturation monitoring device based on the optical fiber - active heating method. The embodiment of the present invention will not be elaborated here.

[0038] In the specification provided herein, numerous specific details are set forth. It will be understood, however, that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

[0039] Similarly, it should be understood that in order to streamline this disclosure and help understand one or more of the various inventive aspects, in the foregoing description of the exemplary embodiments of the invention, the various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof. However, the disclosed method should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, the inventive aspects lie in less than all the features of the single foregoing disclosed embodiment, as reflected in the claims. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of the invention.

[0040] It should be noted that the above embodiments are illustrative of the invention and not restrictive thereof, and that alternative embodiments may be devised by those skilled in the art without departing from the scope of the appended claims.

Claims

1. A carbon dioxide saturation monitoring device based on the optical fiber-active heating method, characterized in that, The carbon dioxide saturation monitoring device based on the optical fiber-active heating method includes: a heating system, a temperature acquisition system, and a monitoring system. The monitoring system is buried at the drilling position of the rock mass, and the monitoring system is electrically connected to the heating system and the monitoring system respectively. The monitoring system is used to generate a target environment by the optical fiber-active heating method. The heating system is used to provide the electric energy required for heating for the monitoring system. The temperature acquisition system is used to obtain temperature data from the monitoring system. The monitoring system includes a line integration box and a monitoring pipe. The monitoring pipe is buried at the drilling position of the rock mass. The upper end of the monitoring pipe is connected to the line integration box. The line integration box is located outside the rock mass. The line integration box is respectively connected to the monitoring pipe and the heating system, and connected to the monitoring pipe and the temperature acquisition system. Among them, at least an electric heating connection port and a temperature data transmission port are included on the line integration box. The electric heating connection port is electrically connected to the heating system, and the temperature data transmission port is connected to the temperature acquisition system.

2. The carbon dioxide saturation monitoring device based on the optical fiber-active heating method according to claim 1, wherein: The carbon dioxide saturation monitoring device based on the optical fiber-active heating method further includes a terminal. The terminal is connected to the temperature acquisition system and is used to determine the carbon dioxide saturation data of the target formation according to the temperature data obtained by the temperature acquisition system.

3. The carbon dioxide saturation monitoring device based on the optical fiber-active heating method according to claim 1, characterized in that: A receiving cavity is hollowed out between the inner wall and the outer wall of the monitoring pipe, and a plurality of sensors are evenly spaced in the receiving cavity.

4. The carbon dioxide saturation monitoring device based on the optical fiber-active heating method according to claim 3, wherein: The diameter of the outer wall matches the inner diameter of the drilling hole.

5. The carbon dioxide saturation monitoring device based on the optical fiber-active heating method according to claim 3, characterized in that: The sensor includes a steel pipe, a flange, a heating resistance wire, and a temperature measurement optical cable. The steel pipe is a hollow cylindrical structure. Flanges are respectively arranged at both ends of the steel pipe, and the heating resistance wire and the temperature measurement optical cable are respectively passed through the flanges. The heating resistance wire is electrically connected to the heating system through the electric heating connection port.

6. The carbon dioxide saturation monitoring device based on the optical fiber - active heating method according to claim 1, wherein: The heating system includes a power supply, a voltage regulator, and an electric wire. The voltage regulator is electrically connected to the power supply and the electric heating connection port respectively through the electric wire.

7. The carbon dioxide saturation monitoring device based on the optical fiber-active heating method according to claim 6, wherein: A control switch is arranged on the electric wire between the power supply and the voltage regulator.

8. The carbon dioxide saturation monitoring device based on the optical fiber-active heating method according to claim 1, wherein: The temperature acquisition system includes a DTS demodulator and a jumper wire. The DTS demodulator is electrically connected to the temperature data transmission port through the jumper wire.

9. A method for monitoring carbon dioxide saturation based on the optical fiber - active heating method, which is applied to the device for monitoring carbon dioxide saturation based on the optical fiber - active heating method according to any one of claims 1 - 8, and is characterized in that, It includes the following steps: S1. Lay the monitoring system at the designated drilling position, and connect the corresponding connection ports of the heating resistance wire and the temperature measurement optical cable in the line integration box, that is, the electric heating connection port and the temperature data transmission port, to the heating system and the temperature acquisition system respectively. S2. Before the heating system works, perform initial data reading through the temperature acquisition system to confirm that the heating system and the temperature acquisition system are in a normal working state. Start the power supply, control switch, and voltage regulator of the heating system in sequence to continuously heat the heating resistance wire, and record the heating time at the same time. Read the temperature data of the temperature acquisition system in real time through the DTS demodulator. After the heating time reaches the set time, turn off the power supply, control switch, and voltage regulator to stop heating the heating resistance wire, and save the temperature data read by the DTS demodulator. S3. Determine the carbon dioxide saturation data of the target formation according to the temperature data.

10. The method for monitoring carbon dioxide saturation based on the optical fiber-active heating method according to claim 9, wherein In step S3, the determination of the carbon dioxide saturation data of the target formation according to the temperature data includes: According to the temperature change Δ T and the linear relationship with the logarithm of the set heating time ln t : the thermal conductivity λ of the rock and soil medium is calculated, where t is the set heating time, and Δ T is the change in temperature data within the set heating time t, q is the heat transferred by the heating resistance wire per unit length per unit time, λ is the thermal conductivity of the rock and soil medium, M is a constant; According to the quantitative relationship between the thermal conductivity of the rock and soil medium λ and the water saturation in the rock mass S w calculate and determine the water saturation in the rock mass S w as well as the saturation of carbon dioxide 1 - S w .

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