Device and method for monitoring scale formation in geothermal fluid pipelines based on spectrum induced polarization

Abstract

The invention discloses a geothermal fluid pipeline scaling monitoring device based on spectrum induced polarization and a method thereof. The monitoring device comprises a probe assembly, which comprises an excitation electrode and a receiving electrode installed on a moving mechanism, and is carried by the moving mechanism to move in the geothermal fluid pipeline; the spectrum induced polarization instrument is used to generate an excitation signal and transmit it to the excitation electrode; the receiving electrode collects the polarization signal generated by the polarization reaction and transmits it to the control module; the control module is connected with the spectrum induced polarization instrument, the moving mechanism and the data acquisition module, and is used to calculate the output peak frequency of the spectrum induced polarization instrument according to the real-time temperature, the real-time pressure and the real-time ion intensity, and determine whether to adjust the output frequency range of the spectrum induced polarization instrument according to the output peak frequency; the moving mechanism is controlled to carry the probe assembly to rise or fall in the geothermal fluid pipeline, and according to the polarization signal collected by the receiving electrode, determine whether the geothermal fluid pipeline is scaled, and issue a scaling warning when scaling occurs.

Description

Technical Field

[0001] The invention relates to pipeline structure monitoring technology, and in particular to a geothermal fluid pipeline scaling monitoring device based on spectrum induced polarization and a method thereof. Background Art

[0002] Medium and high temperature geothermal power stations use underground hot water or steam to drive turbines to generate electricity. It is a clean and renewable energy technology. However, in this process, the dissolved minerals and gases contained in the geothermal fluid will precipitate under specific physical conditions (such as lower temperature and reduced pressure) to form scale. These scales mainly include the deposition of minerals such as silicates, carbonates, and sulfates. Scaling will not only reduce the effective diameter of geothermal fluid pipelines and reduce the fluidity of geothermal fluids, but may also cause corrosion and blockage of pipelines, pumps and other equipment. In severe cases, it may even lead to the scrapping of geothermal fluid pipelines.

[0003] At present, the monitoring of geothermal fluid pipeline scaling mainly relies on physical sampling and chemical analysis methods. These methods usually involve taking samples from geothermal wells at regular intervals, and then analyzing the samples in the laboratory to determine the type and content of minerals. Although these methods are relatively reliable in terms of analytical accuracy, they have obvious limitations: first, these methods cannot achieve continuous monitoring and can only provide data at a certain moment, which is difficult to reflect the dynamic process of geothermal fluid pipeline scaling; second, the sampling and analysis process is cumbersome and time-consuming, and the accuracy of the results may be affected by changes in the samples during transportation and processing; finally, this method has a large interference with the equipment, and requires regular maintenance and overhaul of the geothermal wells, which increases operating costs.

[0004] In the current state of technological development, although there have been some attempts to perform continuous monitoring by installing sensors and other equipment, these methods can often only provide limited information, such as physical parameters such as temperature and pressure, and can only monitor and evaluate whether scaling has occurred in the pipeline after scaling has occurred. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the geothermal fluid pipeline scaling monitoring device and method based on spectral induced polarization provided by the present invention solves the problem that the existing geothermal fluid pipeline scaling method needs to monitor only when scaling has occurred in the pipeline and cannot provide early warning.

[0006] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

[0007] In a first aspect, a geothermal fluid pipeline scaling monitoring device based on spectral induced polarization is provided, comprising:

[0008] A probe assembly, comprising an exciting electrode and a receiving electrode, wherein the exciting electrode and the receiving electrode are both mounted on a moving mechanism and are moved in a geothermal fluid pipeline by the moving mechanism;

[0009] The spectrum induced polarization instrument is used to generate an excitation signal and transmit it to the target monitoring area through the excitation electrode, so that the ions at the solid-liquid interface of the geothermal fluid and the geothermal fluid pipeline undergo polarization migration; the receiving electrode collects the polarization signal generated by the polarization process;

[0010] A data acquisition module is used to collect the real-time temperature, real-time pressure and real-time ion intensity in the geothermal fluid pipeline and send them to the control module;

[0011] The control module is connected with the spectrum induced polarimeter, the moving mechanism and the data acquisition module, and is used for calculating the output peak frequency of the spectrum induced polarimeter according to the real-time temperature, the real-time pressure and the real-time ion intensity; and judging whether the output peak frequency is within the output frequency range of the spectrum induced polarimeter, if not, adjusting the output frequency range to cover the initial peak frequency and the output peak frequency; otherwise, not adjusting the output frequency range; controlling the spectrum induced polarimeter to generate an excitation signal according to the output frequency range; controlling the moving mechanism to carry the probe assembly to rise or fall in the geothermal fluid pipeline and obtain the polarization signal collected by the receiving electrode, and determining whether the geothermal fluid pipeline is scaled according to the polarization signal and the output peak frequency, and issuing a scaling warning when scaling occurs.

[0012] Furthermore, the moving mechanism includes a power module electrically connected to the control module and an electromagnet plate electrically connected to the power module through a power cable, an insulating isolation plate is fixed on the electromagnet plate, and the excitation electrode and the receiving electrode are both fixed on the isolation plate; when the electromagnet plate is energized, it is adsorbed on the geothermal fluid pipeline to fix the probe assembly on the geothermal fluid pipeline, and when the electromagnet plate is de-energized, a winder is used to reel in and out the power cable to lift and lower the electromagnet plate, so as to lift and lower the probe assembly; the winder is electrically connected to the control module.

[0013] Furthermore, the moving mechanism includes a slide groove arranged on the inner wall surface of the geothermal fluid pipeline and a slider cooperating with the slide groove, and the excitation electrode and the receiving electrode are both fixed on the slider; the slider is connected to the connecting rope wound on the winder, and the winding machine is used to retract and release the connecting rope to lift and lower the slider, and the winder is electrically connected to the control module.

[0014] Furthermore, the moving mechanism is a radio buoy, the radio buoy is electrically connected to the control module, and the probe assembly is installed on the radio buoy.

[0015] Furthermore, the exciting electrode and the receiving electrode have the same structure, both comprising an electrode rod made of carbon material, the electrode rod being a mesh electrode or having a plurality of micropores thereon; the surface of the electrode rod is coated with a platinum or gold coating.

[0016] Furthermore, the frequency calculation model for calculating the output peak frequency of the spectrum excitation polarimeter is:

[0017] f(T,P,I)==f0·[1+α(T-T0)+β(P-P0)+γ(I-I0)]

[0018] Among them, f(T,P,I) is the output peak frequency of the spectrum induced polarimeter; f0 is the initial peak frequency of the spectrum induced polarimeter; T, P and I are the real-time temperature, real-time pressure and real-time ion intensity respectively; T0, P0 and I0 are the initial temperature, initial pressure and initial ion intensity in the geothermal fluid pipeline at the initial moment respectively; α, β and γ are the proportional coefficients of temperature correction coefficient, pressure correction coefficient and ion intensity respectively.

[0019] Furthermore, the method for constructing the frequency calculation model includes:

[0020] According to the real-time temperature and the initial temperature, the conductivity change σ(T) when the temperature changes is calculated:

[0021] σ(T) = σ0 · [1 + α(T - T0)];

[0022] According to the real-time pressure and the initial pressure, the conductivity change σ(P) when the pressure changes is calculated:

[0023] σ(P) = σ0 · [1 + β(P - P0)];

[0024] According to the real-time ionic strength and the initial ionic strength, the conductivity change σ(I) when the ionic strength changes is calculated:

[0025] σ(I)=σ0·[1+γ(I-I0)];

[0026] According to the changes in conductivity σ(T), σ(P) and σ(I), a frequency calculation model is constructed:

[0027]

[0028] Here, σ is the complex conductivity that takes into account changes in temperature, pressure, and ionic strength.

[0029] Furthermore, the expression for calculating the polarization signal collected by the receiving electrode is:

[0030]

[0031] σ=σ0[1+α(T-T0)+β(P-P0)+γ(I-I0)]

[0032] Among them, σ(ω) is the polarization signal collected by the receiving electrode; |.| is the absolute value; is the phase; σ'(ω) is the real conductivity; σ”(ω) is the imaginary conductivity; ω is the angular frequency; σ is the complex conductivity that takes into account changes in temperature, pressure and ionic strength.

[0033] Further, the method for determining whether the geothermal fluid pipeline is scaled according to the polarization signal and the output peak frequency includes:

[0034] According to the polarization signal and the output peak frequency, a monitoring curve is drawn with the polarization signal as the ordinate and the output peak frequency as the abscissa;

[0035] Obtain a reference curve drawn by the polarization signal and output peak frequency collected during the test calibration process, and extract the reference output peak frequency and reference polarization signal corresponding to each peak on the reference curve;

[0036] Extracting the output peak frequency and polarization signal corresponding to each peak on the monitoring curve, and comparing them with the reference output peak frequency and reference polarization signal of the peak adjacent to it on the reference curve;

[0037] When there is at least one peak output peak frequency or polarization signal that deviates by a preset ratio from a reference output peak frequency or reference polarization signal corresponding to a peak adjacent thereto on the reference curve, it indicates that scaling has occurred in the geothermal fluid pipeline;

[0038] When the output peak frequencies or polarization signals of all peaks do not deviate from the preset ratio of the reference output peak frequencies or reference polarization signals corresponding to the adjacent peaks on the reference curve, it indicates that scaling does not occur in the geothermal fluid pipeline.

[0039] In a second aspect, a monitoring method for a geothermal fluid pipeline scaling monitoring device based on spectral induced polarization is provided, which comprises the steps of:

[0040] The probe assembly is lowered to a preset depth of the geothermal fluid pipeline using a moving mechanism;

[0041] The data acquisition module is used to collect the real-time temperature, real-time pressure and real-time ion intensity in the geothermal fluid pipeline and send them to the control module;

[0042] Calculate the output peak frequency of the spectrum induced polarization instrument according to the real-time temperature, real-time pressure and real-time ion intensity collected by the data acquisition module;

[0043] and determining whether the output peak frequency is within the output frequency range of the spectrum excitation polarimeter; if not, adjusting the output frequency range to cover the initial peak frequency and the output peak frequency; otherwise, not adjusting the output frequency range;

[0044] Control the spectrum induced polarization instrument to generate an excitation signal according to the output frequency range, and transmit it to the target monitoring area through the excitation electrode, so as to cause polarization migration of ions at the solid-liquid interface of the geothermal fluid and the geothermal fluid pipeline;

[0045] The receiving electrode collects the polarization signal generated by the polarization reaction and transmits it to the control module through the cable;

[0046] The control module determines whether the geothermal fluid pipeline is scaled based on the polarization signal and the output peak frequency, and issues a scaling warning when scaling occurs.

[0047] The beneficial effects of the present invention are as follows: the monitoring device can adjust the output frequency range of the spectrum induced polarization instrument in real time according to the real-time temperature, real-time pressure and real-time ion strength in the geothermal fluid pipeline, thereby optimizing the penetration and accuracy of the signal, so that the device can monitor and accurately analyze the early signals of scaling in real time.

[0048] The spectrum induced polarization instrument of this scheme can produce signal fluctuations when scaling material crystals nucleate but have not yet completely attached through the cooperation of the excitation electrodes, and monitor the signal to determine whether scaling has occurred, so as to issue an early warning, which is earlier than other technical warnings; thus, an early warning is issued in time before scaling reaches a critical state, preventing possible equipment damage or efficiency loss.

[0049] This solution uses a combination of electromagnetic plates and isolation plates to monitor scaling at different depths within geothermal fluid pipelines, thereby providing accurate monitoring at different depths, which helps to more comprehensively evaluate and manage geothermal resources. The output frequency range of the spectrum induced polarimeter has an adaptive adjustment function, which can automatically adjust the frequency and amplitude of the signal according to the internal environment of the geothermal fluid pipeline to optimize the penetration and accuracy of the signal.

[0050] Operational flexibility and easy maintenance: Through the control of the electromagnetic plate, the monitoring device can be easily moved to a designated position in the geothermal fluid pipeline or recovered for maintenance, which simplifies the operation process and reduces the dependence on professional operators. At the same time, this monitoring method is simple and easy to operate, and can be widely used in geothermal power plants of different sizes and types, with good prospects for promotion and application.

[0051] Most of the current scaling-related monitoring technologies indirectly reflect the scaling thickness and cannot provide information related to the composition of scaling materials. However, this scheme can obtain the polarization peaks of different scaling components through experimental calibration. The scaling components can be roughly distinguished by the position differences of the collected polarization signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 This is a front view of a geothermal fluid pipeline scaling monitoring device based on spectral induced polarization, in which a data acquisition module and a control module are not shown.

[0053] Figure 2 for Figure 1 A left side view of the structure is shown.

[0054] Figure 3 Flow chart of the geothermal fluid pipeline scaling monitoring method based on spectral induced polarization.

[0055] Among them, 1. power module; 2. receiving module; 3. excitation module; 4. electromagnet plate; 5. isolation plate; 6. excitation electrode; 7. receiving electrode; 8. geothermal fluid pipeline; 9. spectrum excitation polarization instrument. DETAILED DESCRIPTION

[0056] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0057] like Figure 1 and Figure 2 As shown, the geothermal fluid pipeline scaling monitoring device based on spectrum induced polarization provided by this solution includes a spectrum induced polarization instrument 9, a probe assembly, a moving mechanism, a data acquisition module and a control module.

[0058] The probe assembly includes an excitation electrode 6 and a receiving electrode 7, both of which are mounted on a moving mechanism and moved in the geothermal fluid pipeline 8 by the moving mechanism; the data acquisition module is used to collect the real-time temperature, real-time pressure and real-time ion strength in the geothermal fluid pipeline 8.

[0059] The spectrum induced polarimeter 9 has an excitation module 3 and a receiving module 2, which are respectively connected to the excitation electrode 6 and the receiving electrode 7, and are used to generate an excitation signal and transmit it to the target monitoring area through the excitation electrode 6, so that the ions at the solid-liquid interface of the geothermal fluid and the geothermal fluid pipeline undergo polarization migration; the receiving electrode collects the polarization signal generated by the polarization process; the receiving electrode 7 collects the polarization signal generated by the polarization process, and then the spectrum induced polarimeter 9 transmits the polarization signal to the control module through a cable.

[0060] The control module is connected with the spectrum induced polarimeter 9, the moving mechanism and the data acquisition module, and is used for calculating the output peak frequency of the spectrum induced polarimeter 9 according to the real-time temperature, real-time pressure and real-time ion strength, and judging whether the output peak frequency is within the output frequency range of the spectrum induced polarimeter. If not, the output frequency range is adjusted to cover the initial peak frequency and the output peak frequency; otherwise, the output frequency range is not adjusted; the spectrum induced polarimeter 9 is controlled to generate an excitation signal according to the output frequency range; the moving mechanism is controlled to carry the probe assembly to rise or fall in the geothermal fluid pipeline 8 and obtain the polarization signal collected by the receiving electrode, and according to the polarization signal and the output peak frequency, whether the geothermal fluid pipeline 8 is scaled is determined, and a scaling warning is issued when scaling occurs.

[0061] To facilitate understanding of how to adjust the output frequency range, two examples are provided below for illustration: For example, the output frequency range of the spectrum excitation polarization instrument 9 is usually between 0.01 Hz and 1000 Hz. If the initial peak frequency is 500 Hz, and the calculated peak frequency under a certain working condition is 1200 Hz, the control module adjusts the output frequency range to 0.05 Hz to 5000 Hz. If the initial peak frequency is 0.1 Hz, and the calculated peak frequency under a certain working condition is 0.008 Hz, the control module adjusts the output frequency range to 0.005 Hz to 500 Hz. The control module's ability to adjust the output frequency range is limited only by the instrument's performance. If the calculated peak frequency is higher than the upper limit of the instrument's output frequency range or lower than the lower limit of the instrument's output frequency range (which generally does not occur), it is only adjusted to the limit.

[0062] In one embodiment of the present invention, a method for determining whether a geothermal fluid pipeline 8 is scaled based on a polarization signal and an output peak frequency includes:

[0063] According to the polarization signal and the output peak frequency, a monitoring curve is drawn with the polarization signal as the ordinate and the output peak frequency as the abscissa;

[0064] Obtain a reference curve drawn by the polarization signal and output peak frequency collected during the test calibration process, and extract the reference output peak frequency and reference polarization signal corresponding to each peak on the reference curve;

[0065] Extracting the output peak frequency and polarization signal corresponding to each peak on the monitoring curve, and comparing them with the reference output peak frequency and reference polarization signal of the peak adjacent to it on the reference curve;

[0066] When there is at least one peak output peak frequency or polarization signal that deviates by a preset ratio from a reference output peak frequency or reference polarization signal corresponding to a peak adjacent thereto on the reference curve, it indicates that scaling has occurred in the geothermal fluid pipeline;

[0067] When the output peak frequencies or polarization signals of all peaks do not deviate from the preset ratio of the reference output peak frequencies or reference polarization signals corresponding to the adjacent peaks on the reference curve, it indicates that scaling does not occur in the geothermal fluid pipeline.

[0068] The frequency calculation model for calculating the output peak frequency of the spectrum induced polarization instrument 9 in this scheme is preferably:

[0069] f(T,P,I)==f0·[1+α(T-T0)+β(P-P0)+γ(I-I0)]

[0070] Among them, f(T,P,I) is the output peak frequency of the spectrum induced polarimeter; f0 is the initial peak frequency of the spectrum induced polarimeter; T, P and I are the real-time temperature, real-time pressure and real-time ion intensity respectively; T0, P0 and I0 are the initial temperature, initial pressure and initial ion intensity in the geothermal fluid pipeline at the initial moment respectively; α, β and γ are the proportional coefficients of temperature correction coefficient, pressure correction coefficient and ion intensity respectively.

[0071] The spectrum monitoring range of the spectrum induced polarization instrument 9 of this scheme is usually between 0.01Hz and 1000Hz, which can cover most of the solid-liquid interface response process, but the predicted output peak frequency can narrow the peak search range and improve the recognition efficiency. In addition, when the fluid environment changes significantly and causes the peak frequency to exceed the range of 0.01-1000Hz, the receiving frequency range can be adjusted after the peak frequency is automatically predicted according to the above frequency calculation model.

[0072] like Figure 2 As shown, the moving mechanism includes a power module 1 electrically connected to the control module and an electromagnet plate 4 electrically connected to the power module 1 through a power cable, an insulating isolation plate 5 is fixed on the electromagnet plate 4, and an exciting electrode 6 and a receiving electrode 7 are both fixed on the isolation plate 5; when the electromagnet plate 4 is powered on, it is adsorbed on the geothermal fluid pipeline 8 to fix the probe assembly on the geothermal fluid pipeline, and when the electromagnet plate 4 is powered off, a winder is used to retract the power cable to lift the electromagnet plate 4, so as to lift the probe assembly; the winder is electrically connected to the control module.

[0073] The power cable of the electromagnet plate 4 and the cables connecting the exciting electrode 6 and the receiving electrode 7 can be integrated and sealed to avoid being corroded by the geothermal fluid while minimizing the impact on the fluid.

[0074] The present invention also provides a variety of structural forms of mobile mechanisms. Due to their relatively simple structures, the present invention does not provide a corresponding structural diagram.

[0075] The first form of moving mechanism includes a slide groove arranged on the inner wall surface of the geothermal fluid pipeline 8 and a slider matched with the slide groove, and the excitation electrode 6 and the receiving electrode 7 are both fixed on the slider; the slider is connected to the connecting rope wound on the winder, and the winding machine is used to retract and release the connecting rope to lift and lower the slider, and the winder is electrically connected to the control module.

[0076] The second form of the mobile mechanism is a radio buoy, which is electrically connected to the control module, and the exciting electrode 6 and the receiving electrode 7 are installed on the radio buoy.

[0077] The third form of mobile mechanism may be a retractable electrode rod system, which uses a retractable electrode rod design and adjusts the extension length of the electrode rod by remote control or mechanical means to achieve different monitoring depths.

[0078] The fourth form of mobile mechanism can be an adjustable anchor device, which uses similar anchoring technology to fix and adjust the position of the electrode in the geothermal fluid pipeline through mechanical or hydraulic means. This structure can provide a very stable installation method and is suitable for extreme environments.

[0079] The fifth form of mobile mechanism can be a positioning cable or lifting mechanism. Through the positioning cable or lifting mechanical system installed on the top of the geothermal fluid pipeline, the electrode rod can be moved up and down as needed to reach different monitoring depths. This solution is very flexible and can be quickly adjusted to the accurate depth position.

[0080] In implementation, the scheme preferably has the same structure of the exciting electrode 6 and the receiving electrode 7, both of which include an electrode rod made of carbon material, the electrode rod is a mesh electrode or has a plurality of micropores thereon; the surface of the electrode rod is coated with platinum or gold. The electromagnet plate 4 of the scheme can be made of a light alloy material that is resistant to high temperature and corrosion, to ensure long-term stable operation in extreme environments.

[0081] The platinum or gold coating has excellent chemical inertness, electrochemical stability and excellent electrical conductivity, making the excitation electrode 6 and the receiving electrode 7 suitable for electrochemical measurements under long-term exposure to high temperature conditions in geothermal wells. The electrode rod is a mesh electrode or has a plurality of micropores thereon, which can increase the contact area with the geothermal fluid and improve the monitoring sensitivity and response speed.

[0082] In one embodiment of the present invention, a method for constructing a frequency calculation model includes:

[0083] According to the real-time temperature and the initial temperature, the conductivity change σ(T) when the temperature changes is calculated:

[0084] σ(T) = σ0 · [1 + α(T - T0)];

[0085] According to the real-time pressure and the initial pressure, the conductivity change σ(P) when the pressure changes is calculated:

[0086] σ(P) = σ0 · [1 + β(P - P0)];

[0087] According to the real-time ionic strength and the initial ionic strength, the conductivity change σ(I) when the ionic strength changes is calculated:

[0088] σ(I)=σ0·[1+γ(I-I0)];

[0089] According to the changes in conductivity σ(T), σ(P) and σ(I), a frequency calculation model is constructed:

[0090]

[0091] Here, σ is the complex conductivity that takes into account changes in temperature, pressure, and ionic strength.

[0092] During implementation, the expression for calculating the polarization signal collected by the receiving electrode is:

[0093]

[0094] σ=σ0[1+α(T-T0)+β(P-P0)+γ(I-I0)]

[0095] Among them, σ(ω) is the polarization signal collected by the receiving electrode; |.| is the absolute value; is the phase; σ'(ω) is the real conductivity; σ”(ω) is the imaginary conductivity; ω is the angular frequency; σ is the complex conductivity that takes into account changes in temperature, pressure and ionic strength.

[0096] like Figure 3 As shown, the present solution also provides a monitoring method for a geothermal fluid pipeline 8 scaling monitoring device based on spectrum induced polarization, the method S comprises steps S1 to S7 including the steps of:

[0097] S1. Use a mobile mechanism to lower the probe assembly to a preset depth of the geothermal fluid pipeline;

[0098] S2, using a data acquisition module to collect real-time temperature, real-time pressure and real-time ion intensity in the geothermal fluid pipeline, and sending them to a control module;

[0099] S3, calculating the output peak frequency of the spectrum induced polarization instrument according to the real-time temperature, real-time pressure and real-time ion intensity collected by the data acquisition module;

[0100] S4, and judging whether the output peak frequency is within the output frequency range of the spectrum excitation polarimeter, if not, adjusting the output frequency range to cover the initial peak frequency and the output peak frequency; otherwise, not adjusting the output frequency range;

[0101] S5, controlling the spectrum induced polarization instrument to generate an excitation signal according to the output frequency range, and transmitting the excitation signal to the target monitoring area through the excitation electrode, so that the ions at the solid-liquid interface of the geothermal fluid and the geothermal fluid pipeline undergo polarization migration;

[0102] S6. The receiving electrode collects the polarization signal generated by the polarization reaction and transmits it to the control module through a cable;

[0103] S7. The control module determines whether the geothermal fluid pipeline is scaled according to the polarization signal and the output peak frequency, and issues a scaling warning when scaling occurs.

[0104] In summary, the monitoring device can adjust the output frequency of the spectrum induced polarization instrument 9 in real time according to the environmental changes in the geothermal fluid pipeline 8 to improve the penetration and accuracy of the signal, so as to accurately analyze the early signals of scaling.

Claims

1. A geothermal fluid pipeline scaling monitoring device based on spectral induced polarization, characterized in that: include: A probe assembly, comprising an exciting electrode and a receiving electrode, wherein the exciting electrode and the receiving electrode are both mounted on a moving mechanism and are moved in a geothermal fluid pipeline by the moving mechanism; Spectral induced polarization instrument, used to generate excitation signals and transmit them to the target monitoring area through excitation electrodes, so as to cause polarization migration of ions at the solid-liquid interface of geothermal fluid and geothermal fluid pipeline; The receiving electrode collects the polarization signal generated during the polarization process; A data acquisition module is used to collect the real-time temperature, real-time pressure and real-time ion intensity in the geothermal fluid pipeline and send them to the control module; A control module is connected to the spectrum induced polarimeter, the moving mechanism and the data acquisition module, and is used to calculate the output peak frequency of the spectrum induced polarimeter according to the real-time temperature, the real-time pressure and the real-time ion intensity; and to determine whether the output peak frequency is within the output frequency range of the spectrum induced polarimeter, and if not, to adjust the output frequency range so that it covers the initial peak frequency and the output peak frequency; Otherwise, the output frequency range is not adjusted; the spectrum induced polarimeter is controlled to generate an excitation signal according to the output frequency range; the moving mechanism is controlled to carry the probe assembly up or down in the geothermal fluid pipeline and obtain the polarization signal collected by the receiving electrode, and whether the geothermal fluid pipeline is scaled is determined according to the polarization signal and the output peak frequency, and a scaling warning is issued when scaling occurs; The frequency calculation model for calculating the output peak frequency of the spectrum excitation polarimeter is: in, is the output peak frequency of the spectrum excitation polarimeter; f 0 is the initial peak frequency of the spectrum excitation polarimeter; T , P and I They are real-time temperature, real-time pressure and real-time ion strength; T 0. P 0 and I 0 are the initial temperature, initial pressure and initial ionic strength in the geothermal fluid pipeline at the initial moment; α , β and γ are the temperature correction factor, pressure correction factor and proportionality factor of ion intensity respectively; The expression for calculating the polarization signal collected by the receiving electrode is: ， ， in, The polarization signal collected by the receiving electrode; To take the absolute value; φ is the phase; is the real conductivity; is the imaginary conductivity; ω is the angular frequency; ; 𝜎 is the complex conductivity that takes into account changes in temperature, pressure and ionic strength.

2. The geothermal fluid pipeline scaling monitoring device according to claim 1, characterized in that: The moving mechanism includes a power module electrically connected to the control module and an electromagnet plate electrically connected to the power module via a power cable, an insulating isolation plate is fixed to the electromagnet plate, and the excitation electrode and the receiving electrode are both fixed to the isolation plate; when the electromagnet plate is powered on, it is adsorbed on the geothermal fluid pipeline to fix the probe assembly on the geothermal fluid pipeline, and when the electromagnet plate is powered off, a winder is used to retract the power cable to lift the electromagnet plate and lift the probe assembly; the winder is electrically connected to the control module.

3. The geothermal fluid pipeline scaling monitoring device according to claim 1, characterized in that: The moving mechanism includes a slide groove arranged on the inner wall surface of the geothermal fluid pipeline and a slider matched with the slide groove, and the excitation electrode and the receiving electrode are both fixed on the slider; the slider is connected to the connecting rope wound on the winder, and the winding machine is used to retract and release the connecting rope to lift and lower the slider, and the winder is electrically connected to the control module.

4. The geothermal fluid pipeline scaling monitoring device according to claim 1, characterized in that: The moving mechanism is a radio buoy, the radio buoy is electrically connected to the control module, and the probe assembly is installed on the radio buoy.

5. The geothermal fluid pipeline scaling monitoring device according to claim 1, characterized in that: The exciting electrode and the receiving electrode have the same structure, both comprising an electrode rod made of carbon material, the electrode rod being a mesh electrode or having a plurality of micropores thereon; the surface of the electrode rod is coated with a platinum or gold coating.

6. The geothermal fluid pipeline scaling monitoring device according to claim 1, characterized in that: The method for constructing the frequency calculation model includes: Calculate the conductivity change when the temperature changes based on the real-time temperature and the initial temperature : ； Calculate the conductivity change when the pressure changes based on the real-time pressure and the initial pressure : ； Calculate the conductivity change when the ionic strength changes based on the real-time ionic strength and the initial ionic strength : ； According to the change of conductivity 、 and , build a frequency calculation model: Where 𝜎 is the complex conductivity that takes into account changes in temperature, pressure, and ionic strength.

7. The geothermal fluid pipeline scaling monitoring device according to claim 1, characterized in that: The method for determining whether a geothermal fluid pipeline is fouled based on the polarization signal and the output peak frequency includes: According to the polarization signal and the output peak frequency, a monitoring curve is drawn with the polarization signal as the ordinate and the output peak frequency as the abscissa; Obtain a reference curve drawn by the polarization signal and output peak frequency collected during the test calibration process, and extract the reference output peak frequency and reference polarization signal corresponding to each peak on the reference curve; Extracting the output peak frequency and polarization signal corresponding to each peak on the monitoring curve, and comparing them with the reference output peak frequency and reference polarization signal of the peak adjacent to it on the reference curve; When there is at least one peak output peak frequency or polarization signal that deviates by a preset ratio from a reference output peak frequency or reference polarization signal corresponding to a peak adjacent thereto on the reference curve, it indicates that scaling has occurred in the geothermal fluid pipeline; When the output peak frequencies or polarization signals of all peaks do not deviate from the preset ratio of the reference output peak frequencies or reference polarization signals corresponding to the adjacent peaks on the reference curve, it indicates that scaling does not occur in the geothermal fluid pipeline.

8. A monitoring method for geothermal fluid pipeline scaling monitoring device based on spectrum induced polarization according to any one of claims 1 to 7, characterized in that: Includes steps: The probe assembly is lowered to a preset depth of the geothermal fluid pipeline using a moving mechanism; The data acquisition module is used to collect the real-time temperature, real-time pressure and real-time ion intensity in the geothermal fluid pipeline and send them to the control module; Calculate the output peak frequency of the spectrum induced polarization instrument according to the real-time temperature, real-time pressure and real-time ion intensity collected by the data acquisition module; Determine whether the output peak frequency is within the output frequency range of the spectrum excitation polarimeter. If not, adjust the output frequency range to cover the initial peak frequency and the output peak frequency. Otherwise, the output frequency range is not adjusted; Control the spectrum induced polarization instrument to generate an excitation signal according to the output frequency range, and transmit it to the target monitoring area through the excitation electrode, so as to cause polarization migration of ions at the solid-liquid interface of the geothermal fluid and the geothermal fluid pipeline; The receiving electrode collects the polarization signal generated by the polarization reaction and transmits it to the control module through the cable; The control module determines whether the geothermal fluid pipeline is scaled based on the polarization signal and the output peak frequency, and issues a scaling warning when scaling occurs.

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