High temperature molten salt leak detection apparatus and method

Abstract

The application discloses a high-temperature molten salt leakage detection device, which comprises a detection chamber, wherein the detection chamber is communicated with a pipe side connecting port and a sensor port, and a resistance detection probe is arranged in the sensor port. The application further discloses a high-temperature molten salt leakage detection method, which comprises the following steps: device deployment and pre-operation preparation, real-time online monitoring, leakage signal triggering and alarm, interlocking protection execution, device self-cleaning and automatic reset. The high-temperature molten salt leakage detection device and method integrate a high-precision resistance detection circuit and a quick response logic, can quickly output an alarm signal and be directly connected to an industrial control system, timely trigger an interlocking protection action, effectively prevent leakage expansion, and guarantee the safety of personnel and equipment; the real-time, all-weather and full-automatic molten salt leakage monitoring can make up for the disadvantages of the artificial inspection, such as the inability to continuously cover, the insensitivity to slight leakage, the response lag of the pressure monitoring method and the incapability of discovering large leakage.

Description

Technical Field

[0001] This invention belongs to the field of molten salt leakage detection technology, and relates to a high-temperature molten salt leakage detection device and a high-temperature molten salt leakage detection method. Background Technology

[0002] Molten salt, with its high heat storage density, excellent thermal stability, low vapor pressure, and relatively low cost, is widely used in chemical fields such as solar thermal power generation and industrial waste heat recovery. However, due to its extremely high permeability at high temperatures, molten salt is prone to leakage, necessitating real-time monitoring and alarm systems. Currently, molten salt leak detection mainly relies on manual inspection and pressure monitoring, with intelligent devices accounting for less than 20%. Manual inspection cannot achieve real-time, 24 / 7, and fully automatic alarms, and is insensitive to minor leaks; while pressure monitoring methods can only detect larger leaks, with significant response lag. Therefore, there is an urgent need for a new type of high-temperature molten salt leak detection device that can adapt to high-temperature environments, respond quickly to minute molten salt leaks, automatically reset, and provide real-time monitoring. Summary of the Invention

[0003] The purpose of this invention is to provide a high-temperature molten salt leakage detection device, which solves the problems of existing technologies such as insensitivity to trace amounts of molten salt leakage, lack of adaptability to high-temperature environments, and inability to automatically reset and reuse molten salt leakage real-time monitoring devices.

[0004] Another objective of this invention is to provide a method for detecting high-temperature molten salt leaks.

[0005] The technical solution adopted in this invention is a high-temperature molten salt leakage detection device, which includes a detection chamber connected to a pipe-side connection port and a sensor port, and a resistance detection probe is installed inside the sensor port.

[0006] The invention is further characterized by: The resistance detection probe includes an electrode rod; one end of the electrode rod is connected to the industrial control system through a safety barrier, and the other end of the electrode rod is connected to an electrode head, which is set in the detection chamber. An insulating seal is fitted between the outer wall of the electrode rod and the inner wall of the sensor port.

[0007] The electrode head is provided with a first nitrogen purging port and a second nitrogen purging port on both sides, which are connected to a nitrogen source; a drain pipe is provided in the detection chamber.

[0008] An entrance fence is detached and connected at the pipe-side connection port.

[0009] A heat tracing chamber is provided between the inner and outer walls of the detection chamber. The heat tracing chamber is connected to the steam inlet and the condensate outlet, respectively. A temperature measuring port is provided on the outer wall of the detection chamber.

[0010] Another technical solution adopted in this invention is a high-temperature molten salt leakage detection method, comprising the following steps: Step 1: Equipment deployment and pre-operation preparation; Step 2: Real-time online monitoring; Step 3: Leakage signal triggering and alarm; Step 4: Interlock protection is activated; Step 5: Device self-cleaning and automatic reset.

[0011] Another feature of the technical solution of the present invention is that: Step 1 includes: installing the high-temperature molten salt leakage detection device in a predetermined position, allowing the leaking molten salt to flow naturally into the detection chamber by gravity; starting the heat tracing system, introducing the heat tracing medium into the heat tracing chamber of the detection chamber through the steam inlet, and monitoring and maintaining the internal temperature of the detection chamber above the freezing point of the molten salt in real time through the temperature measuring port; connecting the electrode rod of the resistance detection probe to the industrial control system through the safety barrier, and confirming that the electrode head and the grounding terminal maintain a preset insulation resistance value under normal conditions.

[0012] Step 2 includes: The industrial control system continuously acquires the loop resistance and current signal between the resistance detection probe and the common ground terminal through the safety barrier; Step 3 includes: when molten salt leakage occurs, liquid molten salt flows into the detection chamber, gathers at the bottom of the chamber and touches the electrode head, so that the electrode head and the inner wall of the detection chamber body form a conductive circuit through the molten salt; when the circuit resistance drops below the preset threshold, the safety barrier detects the sudden change in current and outputs an open circuit alarm signal to the industrial control system.

[0013] Step 4 includes: After receiving the alarm signal output by the safety barrier, the industrial control system immediately executes the preset interlock protection program, stops the operation of the molten salt pump and closes the relevant valves, cuts off the molten salt delivery path, and triggers the audible and visual alarms at the site and in the control room.

[0014] Step 5 includes: After the leakage accident is handled, remotely open the control valve on the nitrogen delivery pipeline to introduce high-purity nitrogen into the first nitrogen purging port and the second nitrogen purging port; control the nitrogen to be introduced into the purging port according to the preset timing logic to blow the residual liquid molten salt and deposits in the chamber to the drain pipe and discharge them; after the purging is completed, close the nitrogen valve, the electrode head surface returns to a clean state, the circuit resistance automatically rises back to the normal insulation range, and the device re-enters the real-time online monitoring state.

[0015] The beneficial effects of this invention are: Integrating high-precision resistance detection circuits and fast-response logic, it can quickly output alarm signals and directly connect to industrial control systems, promptly triggering interlock protection actions to effectively prevent leakage from escalating and ensure the safety of personnel and equipment. It can achieve real-time, all-weather, and fully automatic molten salt leakage monitoring, making up for the shortcomings of manual inspections, such as their inability to provide continuous coverage and sensitivity to minor leaks, as well as the lag in response of pressure monitoring methods, which can only detect larger leaks.

[0016] Employing a single-electrode detection structure, with the device housing as the common ground terminal, a conductive circuit can be formed simply by molten salt simultaneously contacting the detection probe and the inner wall of the chamber. This avoids the shortcomings of dual electrodes, which require simultaneous wetting of both electrodes. It exhibits excellent detection sensitivity for trace molten salt leaks, with clear signal change characteristics, making it easy to accurately distinguish between normal and leaking states.

[0017] It features self-cleaning and automatic reset functions. After a leak is dealt with, nitrogen purging can be remotely controlled to remove residual molten salt and deposits in the chamber using airflow fields at different times, restoring the detection probe to a clean state. It can be put back into monitoring without manual cleaning or disassembly. The matching heating system can maintain the temperature of the detection area above the solidification point of the molten salt, preventing the leaked molten salt from solidifying and blocking the detection channel, and supports continuous multiple trigger detections.

[0018] It boasts high operational reliability and low risk of false alarms and malfunctions. An impurity-blocking structure prevents solid particles from entering the detection area, avoiding false alarms and flow channel blockage caused by conductive impurities. This structure is also detachable for easy maintenance during shutdown. A reliable electrical isolation design ensures stable operation of the detection circuit. The accompanying safety barrier features voltage and current limiting functions, meets explosion-proof standards, and is suitable for flammable and explosive industrial environments.

[0019] It has strong environmental adaptability and is applicable to a wide range of scenarios; the parts that come into direct contact with molten salt can be made of high-temperature and corrosion-resistant materials, and the surface of the detection probe can be treated with anti-oxidation to extend the service life of the device; the heat tracing method can be flexibly selected according to the site conditions, and it is suitable for the needs of different industrial devices without steam sources; it can be installed at key nodes of equipment such as molten salt pipelines and reactors, and is applicable to multiple chemical fields such as solar thermal power generation and industrial waste heat recovery. Attached Figure Description

[0020] Figure 1 This is a structural schematic diagram of an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the first type of entrance fence in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of the second type of entrance fence in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the third type of entrance fence in this embodiment of the invention; Figure 5This is a schematic diagram of the structure of the fourth type of entrance fence in this embodiment of the invention.

[0021] In the diagram, 1 is the detection chamber; 2 is the entrance fence; 3 is the pipe-side connection port; 4 is the sensor port; 5 is the first nitrogen purging port; 6 is the second nitrogen purging port; 7 is the temperature measuring port; 8 is the steam inlet; 9 is the condensate outlet; 10 is the drain pipe; 11 is the electrode head; 12 is the insulating seal; and 13 is the electrode rod. Detailed Implementation

[0022] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0023] Example 1 This embodiment proposes a high-temperature molten salt leakage detection device, including a detection chamber 1, which is connected to a pipe-side connection port 3 and a sensor port 4. A resistance detection probe is installed inside the sensor port 4.

[0024] Example 2 Based on Embodiment 1, this embodiment proposes a resistance detection probe including an electrode rod 13; one end of the electrode rod 13 is connected to the industrial control system through a safety barrier, and the other end of the electrode rod 13 is connected to an electrode head 11. The electrode head 11 is set in the detection chamber 1, and an insulating seal 12 is fitted between the outer wall of the electrode rod 13 and the inner wall of the sensor port 4.

[0025] Example 3 Based on Example 1, this example proposes that the electrode head 11 is provided with a first nitrogen purge port 5 and a second nitrogen purge port 6 on both sides, and the first nitrogen purge port 5 and the second nitrogen purge port 6 are connected to a nitrogen source; a drain pipe 10 is provided in the detection chamber 1.

[0026] Example 4 Based on Example 1, this example proposes that an inlet fence 2 is detached and connected at the pipe-side connection port 3; a heat tracing cavity is provided between the inner wall and the outer wall of the detection chamber 1, and the heat tracing cavity is connected to the steam inlet 8 and the condensate outlet 9 respectively; a temperature measuring port 7 is provided on the outer wall of the detection chamber 1.

[0027] Example 5 This embodiment proposes a method for detecting high-temperature molten salt leaks, including the following steps: Step 1: Equipment deployment and pre-operation preparation; Step 2: Real-time online monitoring; Step 3: Leakage signal triggering and alarm; Step 4: Interlock protection is activated; Step 5: Device self-cleaning and automatic reset.

[0028] Example 6 Based on Example 5, this example proposes that step 1 includes: attaching the high-temperature molten salt leakage detection device to the lower part of the molten salt pipeline or equipment with a high risk of leakage, so that the leaking molten salt can flow into the detection chamber 1 naturally by gravity; starting the heat tracing system, introducing the heat tracing medium into the heat tracing cavity of the detection chamber 1 through the steam inlet 8 or starting the electric heat tracing system, and monitoring and maintaining the internal temperature of the detection chamber 1 above the solidification point of the molten salt in real time through the temperature measuring port 7 to prevent the molten salt from solidifying and blocking the detection channel; connecting the electrode rod 13 of the resistance detection probe to the industrial control system through the safety barrier, confirming that the detection chamber 1 body and the molten salt pipeline or equipment shell connected to it serve as a common grounding terminal, and maintaining a preset insulation resistance value between the electrode head 11 and the grounding terminal under normal conditions.

[0029] Step 2 includes: The industrial control system continuously collects the loop resistance and current signal between the resistance detection probe and the common ground terminal through the safety barrier to achieve real-time monitoring around the clock; Step 3 includes: when molten salt leakage occurs, liquid molten salt drips down the pipe or equipment wall and flows into the detection chamber 1. After gathering at the bottom of the chamber, it touches the electrode head 11, so that the electrode head 11 and the inner wall of the detection chamber 1 form a conductive circuit through the molten salt; the circuit resistance drops sharply to below the preset threshold, the circuit current rises instantaneously, and the safety barrier outputs an open circuit alarm signal to the industrial control system after detecting the sudden change in current. Step 4 includes: After receiving the alarm signal output by the safety barrier, the industrial control system immediately executes the preset interlock protection program, stops the operation of the molten salt pump and closes the relevant valves, cuts off the molten salt delivery path, and triggers the audible and visual alarms at the site and in the control room to prompt the operators to carry out subsequent handling work. Step 5 includes: After the leak accident is handled, the operator or the industrial control system remotely opens the control valve on the nitrogen delivery pipeline to introduce high-purity nitrogen into the first nitrogen purging port 5 and the second nitrogen purging port 6; according to the preset timing logic, the two purging ports are alternately or simultaneously introduced with nitrogen to form a directional, reciprocating oscillation or pulse collision airflow field in the detection chamber 1, which blows the residual liquid molten salt and deposits in the chamber to the drain pipe 10 and discharges them; after the purging is completed, the nitrogen valve is closed, the surface of the electrode head 11 returns to a clean state, the circuit resistance automatically rises back to the normal insulation range, and the device can automatically reset without disassembly and re-enter the real-time monitoring state.

[0030] This invention integrates a high-precision resistance detection circuit with fast-response logic. The total response time from the molten salt contact probe to the safety barrier output alarm signal is no more than 0.5 seconds. This signal can be directly connected to the industrial control system to achieve automatic interlocking shutdown, such as stopping the molten salt pump and closing valves, effectively preventing the leakage from escalating and ensuring the safety of personnel and equipment. During equipment operation, it can quickly detect molten salt leakage and trigger an alarm to achieve interlocking shutdown and prevent the accident from escalating. It can achieve real-time, all-weather, and fully automatic alarms; it has high detection accuracy, fast response speed, and real-time monitoring; it automatically resets after purging and can be reused without the need for manual probe cleaning.

[0031] like Figure 1 As shown, in one embodiment of the present invention, the detection chamber 1 is a sealed box-shaped structure with a connection port at its upper part for connecting to the molten salt pipeline or the area below the leak point of the equipment; a sensor port 4 is provided at the upper end of the detection chamber 1 for installing a resistance detection probe; nitrogen purging ports are respectively provided on both sides of the detection chamber 1, wherein the purging direction of the first nitrogen purging port 5 points towards the inlet of the drain pipe 10; a heating chamber is provided outside the shell of the detection chamber 1, which is connected to a steam inlet 8 and a condensate outlet 9 respectively; the resistance detection probe is connected to a safety barrier located in the safety zone via a wire; the output signal of the safety barrier is connected to an industrial control system (such as DCS / PLC) to achieve interlocking shutdown. The components of the detection chamber 1 that are in direct contact with the molten salt are made of ceramics such as alumina, zirconium oxide, high-temperature alloys or S32168, and dissimilar materials are connected by brazing. The surface of the electrode head 11 can be gold-plated or platinum-plated to resist oxidation. The protection level of the instrument and junction box is not lower than IP65, the explosion-proof level is Exd IICT4, and it is equipped with an explosion-proof electrical interface.

[0032] Combination Figures 2 to 5As shown, in one embodiment of the present invention, an inlet grille 2 is installed above the pipe-side connection port 3 of the detection chamber 1 to block solid particles with a diameter larger than the grille gap, allowing only liquid molten salt and tiny particles to pass through. After long-term operation of the molten salt system, solid particles such as coke and welding slag may form on the inner wall of the pipe. Without the grille to block them, these impurities will enter the detection chamber 1 along with the leaked molten salt, which may cause the probe to short-circuit, and conductive impurities such as metal debris may directly connect the probe and the outer shell, leading to false alarms; particle accumulation in the detection chamber 1 may also cause flow channel blockage. The inlet grille 2 is designed to be detachable, such as by clips, screws, or slots; the grille can be removed separately for cleaning when the system is shut down for maintenance. The pipe-side connection port 3 has a funnel-shaped or V-shaped constriction structure; the first nitrogen purging port 5 is located on the opposite side of the sensor port 4 to ensure that the trace amount of leaked molten salt automatically gathers and covers the probe surface. A resistance detection probe is installed inside sensor port 4. This probe adopts a single-electrode structure, including an electrode rod 13, an insulating seal 12, and an electrode head 11. The vertical distance between the lower end face of the electrode head 11 and the bottom of the detection chamber 1 is 2mm-10mm. Even in the case of a slight leakage, the molten salt surface can quickly rise and touch the electrode head 11 under the action of surface tension. In one embodiment of the present invention, the insulating seal 12 is tightly filled between the inner wall of the electrode rod 13 and the sensor port 4, achieving electrical isolation between the electrode rod 13 and the detection chamber 1. The end of the electrode rod 13 is connected to the safety barrier via a wire, and the electrode head 11 connected to its head is exposed inside the detection chamber 1. The detection chamber 1 and the molten salt pipe or equipment housing connected to it serve as a common ground terminal. When the leaked molten salt simultaneously contacts the electrode head 11 and the inner wall of the detection chamber 1, a unique conductive circuit is formed, thereby converting the resistance change into a current or voltage signal. A steam heating or electric heating system is installed outside the detection chamber 1, and the temperature is fed back in real time through the temperature measuring port 7 to ensure that the temperature of the inner wall of the detection chamber 1 and the area around the probe is always higher than the freezing point of the molten salt. Even if the leaked molten salt enters the detection chamber 1, it can remain liquid and will not solidify and block the detection channel, thereby supporting continuous multiple trigger detections.

[0033] In one embodiment of the present invention, a first nitrogen purge port 5 and a second nitrogen purge port 6 are respectively provided in the detection chamber 1. The first nitrogen purge port 5 and the second nitrogen purge port 6 are arranged opposite each other in space, with their central axes on the same horizontal plane or forming a small angle of 0° to 15°, and both pointing towards the interior of the detection chamber 1. The first nitrogen purge port 5 and the second nitrogen purge port 6 are respectively connected to the same nitrogen source or two independent nitrogen sources through independent nitrogen delivery pipelines. Each pipeline is equipped with an independent control valve, preferably a solenoid valve or a pneumatic valve, to realize the on / off and timing control of the gas sources of the two purge ports. During the self-cleaning operation, the control system controls the first nitrogen purge port 5 and the second nitrogen purge port 6 to alternately introduce nitrogen according to the preset timing logic, or to introduce nitrogen into both simultaneously to create a phase difference, thereby forming a reciprocating oscillation or pulse collision airflow field in the detection chamber 1.

[0034] In one embodiment of the present invention, when nitrogen is introduced into the first nitrogen purge port 5 and the second nitrogen purge port 6 is closed, the airflow is directionally purged from right to left, pushing the liquid molten salt and the attached substances towards the left side wall; subsequently, the first nitrogen purge port 5 is closed, and nitrogen is introduced into the second nitrogen purge port 6, and the airflow is reversed from right to left; this is repeated for 2 to 10 cycles, so that the airflow direction is repeatedly reversed in the detection chamber 1.

[0035] In another embodiment of the present invention, nitrogen gas is introduced into the first nitrogen purge port 5 and the second nitrogen purge port 6 at the same time, so that the two gas flows collide in the middle of the detection chamber 1, forming an upward or downward turbulent diffusion field, which impacts and cleans the probe surface and the dead corner area at the top of the chamber.

[0036] In one embodiment of the present invention, the safety barrier is installed in an independent intrinsically safe explosion-proof junction box, which is connected to the detection chamber 1 via an explosion-proof flexible tube or armored cable; the safety barrier integrates a voltage and current limiting circuit, which limits the open-circuit voltage applied to the resistance detection probe to below DC (Direct Current) 12V and the short-circuit current to below 10mA, meeting the intrinsically safe explosion-proof requirements of Exia IIC T4 level.

[0037] In one embodiment of the invention, the device is fitted to the bottom of a pipe, utilizing gravity to allow leaked molten salt to drip naturally or flow along the wall into the detection chamber 1, where it collects around the probe at the lowest point. The probe employs a single-electrode structure, using the tested metal pipe or equipment housing as the zero potential. When the molten salt contacts the probe and ground, a conductive circuit is formed. This design avoids the drawback of traditional dual-electrode systems, which require simultaneous wetting of both electrodes, and produces a significant resistance change even for minute leaks. After a leak alarm is triggered and the interlock shutdown is completed, the operator or control system can remotely open the nitrogen purging valve, directing the accumulated molten salt in the detection chamber 1 towards the drain pipe 10 through the nitrogen purging port. The probe surface becomes clean again, and the resistance automatically returns to its normal insulation state. The device can then be used for the next round of testing without disassembly.

[0038] In one embodiment of this invention, when applied to a high-temperature molten salt pipeline in a tower-type solar thermal power plant: the invention is installed below the pipeline. When a minor crack appears in the pipeline, molten salt leaks and flows into the detection chamber due to gravity, quickly accumulating around the sensor probe at the bottom of the chamber. At this time, the molten salt, acting as a conductive medium, forms a conductive loop between the probe and the pipeline, causing the resistance value to drop sharply from the normal 19kΩ to below 5Ω, and the loop current to rise instantaneously. Upon detecting this sudden current change, the safety barrier outputs an open-circuit signal within 0.5 seconds, triggering the alarm system and interlocking to stop the molten salt circulation pump. Simultaneously, relevant valves are closed to prevent further leakage and to facilitate timely maintenance. Simultaneously, the steam tracing system continuously supplies 1.2MPa low-pressure steam into the jacket of the detection chamber, maintaining the internal temperature above the molten salt's freezing point, ensuring that the leaked molten salt does not solidify or block the detection channel. Upon triggering a leak alarm, the operator remotely opens the nitrogen purging valve, introducing high-purity nitrogen into the detection chamber through the purging port. This purges the accumulated liquid molten salt out of the chamber, restoring the probe surface to a clean state. The resistance value automatically recovers to the normal range of 19kΩ, and the device automatically resets and is ready for the next test. The entire process requires no manual probe cleaning and no system shutdown for maintenance, significantly improving the safety of continuous system operation.

[0039] One embodiment of this invention is applied to a fixed-bed reactor system using high-temperature molten salt heat exchange: the invention is installed at the horizontal pipe at the reactor outlet. The detection chamber adopts a composite structure of S32168 stainless steel and alumina ceramic brazed together. The instrument box and safety barrier have an IP66 protection rating and an explosion-proof mark of Exd IICT4 Gb. All cable interfaces use Exd type explosion-proof glands. Electric heating tape is used instead of steam heating, suitable for chemical plants without a steam source. When a minor leak occurs in the valve packing, the probe resistance drops from the normal value of 10kΩ to below 5Ω. The safety barrier outputs a signal within 0.5 seconds, automatically interlocking and stopping the molten salt pump, closing the valve, etc., and triggering alarms in the field and control room to prevent the leak from expanding. After the leak is dealt with, the residual molten salt is purged, the device automatically resets, and normal monitoring status is restored.

Claims

1. A high-temperature molten salt leakage detection device, characterized in that, It includes a detection chamber (1), which is connected to the pipe-side connection port (3) and the sensor port (4), and a resistance detection probe is installed in the sensor port (4).

2. The high-temperature molten salt leakage detection device according to claim 1, characterized in that, The resistance detection probe includes an electrode rod (13); one end of the electrode rod (13) is connected to the industrial control system through a safety barrier, and the other end of the electrode rod (13) is connected to the electrode head (11). The electrode head (11) is set in the detection chamber (1), and an insulating seal (12) is fitted between the outer wall of the electrode rod (13) and the inner wall of the sensor port (4).

3. The high-temperature molten salt leakage detection device according to claim 2, characterized in that, The electrode head (11) is provided with a first nitrogen purge port (5) and a second nitrogen purge port (6) on both sides, and the first nitrogen purge port (5) and the second nitrogen purge port (6) are connected to a nitrogen source; a drain pipe (10) is provided in the detection chamber (1).

4. The high-temperature molten salt leakage detection device according to claim 1, characterized in that, An entrance fence (2) is detached and connected at the pipe-side connection port (3).

5. The high-temperature molten salt leakage detection device according to claim 1, characterized in that, A heat tracing chamber is provided between the inner wall and the outer wall of the detection chamber (1). The heat tracing chamber is connected to the steam inlet (8) and the condensate outlet (9) respectively. A temperature measuring port (7) is provided on the outer wall of the detection chamber (1).

6. A method for detecting high-temperature molten salt leakage, characterized in that, Using the high-temperature molten salt leakage detection device according to any one of claims 1 to 5 includes the following steps: Step 1: Equipment deployment and pre-operation preparation; Step 2: Real-time online monitoring; Step 3: Leakage signal triggering and alarm; Step 4: Interlock protection is activated; Step 5: Device self-cleaning and automatic reset.

7. The high-temperature molten salt leakage detection method according to claim 6, characterized in that, Step 1 includes: installing the high-temperature molten salt leakage detection device in a predetermined position so that the leaking molten salt can flow into the detection chamber (1) naturally by gravity; starting the heat tracing system and introducing the heat tracing medium into the heat tracing cavity of the detection chamber (1) through the steam inlet (8); monitoring and maintaining the internal temperature of the detection chamber (1) above the solidification point of the molten salt in real time through the temperature measuring port (7); connecting the electrode rod (13) of the resistance detection probe to the industrial control system through the safety barrier and confirming that the electrode head (11) and the grounding terminal maintain a preset insulation resistance value under normal conditions.

8. The high-temperature molten salt leakage detection method according to claim 6, characterized in that, Step 2 includes: the industrial control system continuously acquires the loop resistance and current signal between the resistance detection probe and the common ground terminal through the safety barrier; Step 3 includes: when molten salt leakage occurs, liquid molten salt flows into the detection chamber (1), gathers at the bottom of the chamber and touches the electrode head (11), so that the electrode head (11) and the inner wall of the detection chamber (1) form a conductive circuit through the molten salt; when the circuit resistance drops below the preset threshold, the safety barrier detects the sudden change in current and outputs an open circuit alarm signal to the industrial control system.

9. The high-temperature molten salt leakage detection method according to claim 6, characterized in that, Step 4 includes: after receiving the alarm signal output by the safety barrier, the industrial control system immediately executes the preset interlocking protection program, stops the operation of the molten salt pump and closes the relevant valves, cuts off the molten salt delivery path, and triggers the audible and visual alarms at the site and in the control room.

10. The high-temperature molten salt leakage detection method according to claim 6, characterized in that, Step 5 includes: after the leakage accident is handled, remotely open the control valve on the nitrogen delivery pipeline to introduce high-purity nitrogen into the first nitrogen purging port (5) and the second nitrogen purging port (6); control the purging port to introduce nitrogen according to the preset timing logic to blow the residual liquid molten salt and attachments in the chamber to the drain pipe (10) and discharge them; after the purging is completed, close the nitrogen valve, the surface of the electrode head (11) is restored to a clean state, the circuit resistance automatically rises back to the normal insulation range, and the device re-enters the real-time online monitoring state.

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