An isolated heat exchange device with leakage monitoring function

Abstract

The application discloses an isolated heat exchange device with a leakage monitoring function, a closed pressure-bearing cavity is formed by a heat exchange box and a box cover, pressure relief of a primary side heating cavity medium and impurity intrusion are avoided, a circulating pump and a bidirectional valve constitute a medium self-circulation system, the medium is heated by an electric heating rod and then washed to exchange heat in a heat exchanger, there is no heat exchange dead angle, an isolation cover is arranged outside the heat exchanger, a monitoring cavity is formed between double heat exchange walls, the primary side conductive corrosion medium and the secondary side heat exchange fluid loop are physically separated, medium cross contamination is eliminated, the purity of the secondary side heat exchange medium is ensured, water quality treatment and descaling maintenance operation decoupling of both sides are realized, the heat exchanger cleaning cycle is prolonged, meanwhile, multiple detectors are arranged in the monitoring cavity, and real-time detection can be carried out when heat exchange leakage occurs.

Description

Technical Field

[0001] This application relates to the field of heat exchanger technology, and in particular to an isolated heat exchange device with leakage monitoring function. Background Technology

[0002] In the fields of chemical engineering, power generation, and high-purity process media processing, indirect heat exchange equipment is often used to achieve heat transfer and isolation. Especially in situations involving conductive heating media, corrosive media, or high-purity media, indirect heat exchange equipment that can avoid problems such as media corrosion and contamination is of paramount importance.

[0003] However, in existing high-temperature boilers with heat exchangers, the only separation between the heat exchanger and the high-temperature medium inside the boiler is its own outer wall. Once corrosion, cracks, or perforations occur on the wall, the conductive medium and electrolyte inside the boiler will directly enter the heat exchanger, which will not only contaminate the fluid to be exchanged, but also cause safety accidents such as leakage and medium mixing. In addition, existing heat exchange equipment lacks an effective online leakage monitoring mechanism, and minor leaks are often only discovered after they cause substantial pollution or production stoppage.

[0004] Furthermore, most existing heat exchangers use extended pipe lengths to extend the flow heat exchange path of the internal liquid in order to enhance the heat exchange effect. This structure has a low convective heat transfer coefficient and poor overall heat transfer efficiency. Moreover, dirt easily adheres to the inner or outer wall of the heat exchanger. Over a long period of time, the continuous accumulation of dirt will seriously affect the heat exchange effect. Summary of the Invention

[0005] This application proposes an isolated heat exchange device with leakage monitoring function, which has the advantages of setting two heat exchange walls to avoid media cross-contamination, setting a detector between the two heat exchange walls to monitor leakage, setting an agitator inside the heat exchanger to enhance the heat exchange effect, and the agitator adaptively adjusting to enhance heat exchange. It is used to solve the problems of low heat exchange efficiency, rapid scaling, and media mixing in existing indirect heat exchange equipment in working conditions involving conductive heating media, corrosive media, or high-purity media.

[0006] To achieve the above objectives, this application adopts the following technical solution: an isolated heat exchange device with leakage monitoring function, comprising a heat exchange box and a box cover, wherein a primary heating chamber is formed inside the heat exchange box; multiple heating rods are provided at the bottom end of the box cover, and a gas-liquid separator is provided on one side of the top end of the box cover; multiple sealed heat exchangers are provided in the inner cavity of the heat exchange box, and a sealed isolation cover is provided on the outside of the heat exchangers; the wall of the heat exchanger forms a secondary heat exchange wall, the cover wall of the isolation cover forms a primary heat exchange wall, a monitoring chamber is formed between the secondary heat exchange wall and the primary heat exchange wall, and multiple detectors are provided on the side of the primary heat exchange wall facing the secondary heat exchange wall.

[0007] Preferably, multiple wall temperature sensors are installed on the outer wall of the heat exchange box.

[0008] Preferably, a circulation pump is provided on one side of the heat exchange box. The input end of the circulation pump is connected to the bottom of the primary heating chamber near the heat exchanger. A two-way valve is provided at the output end of the circulation pump. One output end of the two-way valve is connected to the top of the primary heating chamber near the heating rod.

[0009] Preferably, a water pump is provided on one side of the heat exchange box, the output end of the water pump is fixedly connected to the bottom input end of the heat exchanger, and the top output end of the heat exchanger is fixedly connected to the input end of the gas-liquid separator.

[0010] Preferably, the spacing between the monitoring cavities is no more than five millimeters.

[0011] Preferably, the heat exchanger is a tubular heat exchanger, including a preheating section at the bottom, a boiling section in the middle, and a vaporization section at the top. Both the bottom and top ends of the tubular heat exchanger are provided with a metal flexible hose section I. The end of the metal flexible hose section I away from the tubular heat exchanger is provided with a threaded section I. An agitator is provided in the tubular heat exchanger.

[0012] Preferably, the stirring component includes two boss sections disposed at the connection between the preheating section, the boiling section and the vaporization section, and three springs respectively disposed in the preheating section, the boiling section and the vaporization section, with one end of the spring near the boss section fixed to the boss section.

[0013] Preferably, the side of the spring near the inner wall of the tubular heat exchanger has multiple isolation protrusions that fit against the tube wall, and a guide groove is provided at the bottom of the spring facing the liquid impact. Multiple drain grooves that pass through the spring and are inclined towards the axis are provided on the guide groove.

[0014] Preferably, the isolation cover is fitted onto the outside of the tubular heat exchanger. The bottom and top ends of the isolation cover are provided with metal flexible hose section II. The end of the metal flexible hose section II away from the isolation cover is provided with threaded section II. The shape of the isolation cover is the same as that of the tubular heat exchanger. The diameter of each section of the isolation cover from bottom to top is greater than the diameter of each section of the tubular heat exchanger from bottom to top.

[0015] Preferably, the diameter values ​​of the preheating section, boiling section and vaporization section increase progressively, and the spring diameter and pitch in the preheating section, boiling section and vaporization section also increase progressively.

[0016] A control method for an isolated heat exchanger with leakage monitoring function includes: before startup, detecting the initial pressure, conductivity, humidity, liquid level, or medium composition of the monitoring chamber and establishing a reference value; during operation, heating the medium in the primary heating chamber with electric heating rods, and allowing feedwater to sequentially pass through a preheating section, a boiling section, and a vaporization section to form a gas-liquid mixture before entering a gas-liquid separator; continuously or intermittently acquiring monitoring chamber signals during operation; when any of the following conditions occur within 60 seconds: the monitoring chamber pressure changes by more than 5 kPa relative to the reference value, the conductivity reaches more than 10 μS / cm, the relative humidity reaches more than 80%, the liquid level sensor outputs a liquid level signal, or the component detector detects a characteristic component of the primary medium or the secondary feedwater, it is determined that there is a leakage risk in the primary heat exchange wall or the secondary heat exchange wall, and alarm, power reduction, pump stoppage, valve closure, or power failure protection are executed; the above judgment threshold is a default threshold and can be calibrated and adjusted according to the equipment volume, the initial filling pressure of the monitoring chamber, the type of heat transfer medium, and the clean steam level.

[0017] This application provides an isolated heat exchange device with leakage monitoring function. The heat exchange box and the box cover form a sealed pressure-bearing cavity to prevent the medium in the primary heating cavity from depressurizing and impurities from entering. The circulating pump and the two-way valve form a medium self-circulation system. The medium is first fully heated by the electric heating rod and then flushes the heat exchanger for heat exchange, eliminating heat exchange dead zones. An isolation cover is set on the outside of the heat exchanger, and a monitoring cavity is formed between the double heat exchange walls, physically separating the conductive and corrosive medium on the primary side from the heat exchange fluid circuit on the secondary side (this application is applicable to liquid phase heating and can also be applied to various heat exchange scenarios involving phase change (such as vaporization), which is only referred to as such here). This eliminates cross-contamination of the medium and ensures the purity of the heat exchange medium on the secondary side. At the same time, it decouples the water treatment and descaling maintenance operations on both sides, extending the heat exchanger cleaning cycle. In addition, multiple detectors are built into the monitoring cavity to detect leaks in the heat exchange in real time.

[0018] Meanwhile, by designing the heat exchanger as a three-stage progressively expanding tubular structure, it adapts to the entire process of feedwater heating and vaporization expansion, eliminating flow channel blockage and improving vaporization efficiency. Each section has built-in segmented springs to replace traditional micro-ribs and spiral flow channels, reducing processing costs. The outer diameter and pitch of the springs are matched in stages according to the working conditions of single-phase water, two-phase flow, and gaseous media in the tube, enhancing disturbance heat transfer throughout the entire range, inhibiting scaling, and reducing flow resistance of gaseous media. At the same time, the springs can adaptively deform and adjust the flow channel gap according to the medium flow rate and pressure difference, adapting to high and low load conditions. The springs can reciprocate under fluid impact, continuously disrupting the laminar flow of the tube wall and improving the heat transfer coefficient. At the same time, they can slightly scrape the inner wall to clean scale online. Furthermore, the springs are equipped with hemispherical isolation protrusions on the outside to form multi-point support, and the gaps generate micro vortices to further enhance near-wall heat transfer, significantly improving the overall heat transfer performance.

[0019] Meanwhile, Tongben has opened a spiral guide groove at the bottom of the segmented spring, which can gather fluid to enhance the reciprocating vibration driving force of the spring. Even under low flow conditions, it can still maintain efficient turbulence and descaling. Multi-directional drainage grooves are opened on the guide groove to promptly discharge the liquid accumulated in the groove and spray fluid to the center of the flow channel to form strong turbulence, eliminate the central fluid heat exchange blind zone, and make the feed water vaporization more uniform. At the same time, the groove wall of the guide groove is set at an angle to further amplify the spring vibration amplitude. The vibration force drives the heat exchanger and isolation cover to swing synchronously through the metal hose, continuously agitating the medium in the primary side heating chamber, eliminating the primary side flow dead zone, and effectively improving the heat exchange efficiency and unit heat exchange of the primary side medium. Attached Figure Description

[0020] The accompanying drawings, which form part of this specification, illustrate embodiments disclosed in this application and, together with the specification, serve to explain the principles disclosed in this application.

[0021] This disclosure will become clearer with reference to the accompanying drawings and the following detailed description, wherein: Figure 1 This is a schematic diagram of the main structural distribution in Embodiment 1 of the present invention; Figure 2 This is a schematic diagram showing the positions of the primary side heat exchange wall and the secondary side heat exchange wall in Embodiment 1 of the present invention; Figure 3 This is a three-dimensional schematic diagram of the isolation cover in Embodiment 2 of the present invention; Figure 4 This is a three-dimensional schematic diagram of the tubular heat exchanger in Embodiment 2 of the present invention; Figure 5 This is a schematic diagram of the internal structure distribution of the tubular heat exchanger in Embodiment 2 of the present invention; Figure 6 For the present invention Figure 5 Enlarged view of a portion of the structure at point A; Figure 7 This is a schematic diagram of the spring distribution in Embodiment 2 of the present invention; Figure 8 This is a schematic diagram of the spring structure in Embodiment 3 of the present invention.

[0022] The components are as follows: 1. Heat exchange box; 11. Box cover; 12. Primary heating chamber; 13. Heating rod; 14. Wall temperature sensor; 2. Heat exchanger; 21. Secondary heat exchange wall; 22. Preheating section; 23. Boiling section; 24. Vaporization section; 25. Metal hose section I; 26. Threaded section I; 27. Boss section; 3. Primary heat exchange wall; 31. Monitoring chamber; 32. Metal hose section II; 33. Threaded section II; 4. Circulation pump; 41. Two-way valve; 42. Water supply pump; 5. Gas-liquid separator; 6. Spring; 61. Guide groove; 62. Drain groove; 63. Isolation protrusion. Detailed Implementation

[0023] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0024] Example 1 Please see Figure 1 An isolated heat exchange device with leakage monitoring function includes a heat exchange box 1 and multiple functional pipelines for conveying fluid. The top opening of the heat exchange box 1 is fixedly connected to a box cover 11. A primary heating chamber 12 is formed inside the heat exchange box 1. Multiple wall temperature sensors 14 are fixedly connected to the outer wall of the heat exchange box 1.

[0025] This allows the heat exchange box 1 to form a sealed space after the box cover 11 is closed, so that the medium in the primary side heating chamber 12 can be heated in a sealed environment, avoiding internal fluid pressure loss and preventing external impurities from entering the primary side heating chamber 12. At the same time, the wall temperature sensor 14 can monitor the temperature abnormality of the heat exchange box 1 in real time and make corresponding adjustments as soon as possible based on the abnormal temperature.

[0026] The heat exchange box 1 is equipped with a high-pressure adjustable power supply, an electrical parameter detection module, an operating condition parameter detection module, and a control module on its outer side.

[0027] This enables various detection elements in heat exchanger 1 to transmit signals to the existing control module, thereby allowing for real-time control of related equipment based on data analysis.

[0028] Multiple heating rods 13 are fixedly connected to the bottom of the cover 11. The primary heating chamber 12 is filled with a conductive working medium, so that the heating rods 13 can heat the conductive working medium in the primary heating chamber 12 after operation.

[0029] A gas-liquid separator 5 is fixedly connected to one side of the top of the cover 11. The gas-liquid separator 5 is provided with an input end, a gas output end and a liquid output end.

[0030] Multiple heat exchangers 2 are installed in the inner cavity of the heat exchange box 1. The bottom end of the heat exchanger 2 is fixedly inserted through the bottom end of the inner cavity of the heat exchange box 1, and the top end of the heat exchanger 2 is fixedly inserted through the top end of the box cover 11 and is fixedly connected to the input end of the gas-liquid separator 5.

[0031] This design ensures that the inner cavity of heat exchanger 2 is not directly connected to the primary heating chamber 12. The medium to be heated can be input into heat exchanger 2 through the bottom inlet of heat exchanger 2 and undergo heat exchange through the position of heat exchanger 2 inside the primary heating chamber 12. After forming a gas-liquid mixed wet vaporized gas, it is discharged from the top outlet of heat exchanger 2 and enters gas-liquid separator 5 for gas-liquid separation to obtain a dry gaseous medium. The dry gaseous medium is discharged from the gas outlet of gas-liquid separator 5, and the separated liquid is discharged from the liquid outlet.

[0032] A circulation pump 4 is installed on one side of the heat exchange box 1. A pipeline is fixedly connected to the input end of the circulation pump 4. The end of the pipeline away from the circulation pump 4 is fixedly connected to the bottom of the side of the heat exchange box 1 near the heat exchanger 2.

[0033] This allows the circulating pump 4 to draw the medium from the side of the primary heating chamber 12 closest to the heat exchanger 2 through the pipeline, so that the medium in the primary heating chamber 12 can flow to this side, thereby allowing the flowing liquid to flow around the heat exchanger 2 and exchange heat with the heat exchanger 2.

[0034] A two-way valve 41 is fixedly connected to one side of the circulating pump 4. Both openings of the two-way valve 41 away from the circulating pump 4 are fixedly connected to pipelines. One end of the pipeline away from the two-way valve 41 is fixedly connected to the top of the heat exchange box 1 near the heating rod 13 and is connected to the primary heating chamber 12.

[0035] After the circulating pump 4 extracts the medium from the primary heating chamber 12, the two-way valve 41 can open the opening connecting to the primary heating chamber 12, allowing the circulating pump 4 to pump the extracted medium back into the primary heating chamber 12. This medium is input from a position close to the heating rod 13, allowing the liquid to receive direct contact heating from the heating rod 13 at close range. Then, it flows towards the heat exchanger 2 along with the flowing liquid, so that the medium in the primary heating chamber 12 is in a continuous circulating heating flow, ensuring that there is always a high-temperature medium that can effectively exchange heat with the heat exchanger 2.

[0036] Meanwhile, when it is necessary to discharge the medium in the primary heating chamber 12, the two-way valve 41 opens another opening to discharge the medium.

[0037] A water supply pump 42 is installed on one side of the heat exchange box 1. The output end of the water supply pump 42 is fixedly connected to a pipeline, which is fixedly connected to the bottom input end of the heat exchanger 2.

[0038] This allows the water pump 42 to draw water-conditioned liquid into multiple heat exchangers 2 for heat absorption and vaporization. The water-conditioned liquid mentioned here is the product of other equipment in existing high-pressure hydrolysis and polymerization reaction equipment.

[0039] See Figure 2The wall of heat exchanger 2 forms a secondary heat exchange wall 21. An isolation cover is fixedly sleeved on the outside of heat exchanger 2. The wall of the isolation cover forms a primary heat exchange wall 3. A monitoring cavity 31 is formed between the secondary heat exchange wall 21 and the primary heat exchange wall 3. The monitoring cavity 31 is filled with a heat-conducting medium.

[0040] The spacing of the monitoring cavity 31 is between 0.2 mm and 5 mm.

[0041] The monitoring chamber 31 is an empty cavity, or it may be filled with an inert gas, a high thermal conductivity insulating oil, a composite medium of nano thermally conductive filler and gas, or a low boiling point phase change working fluid, or a combination of the above media. When the medium in the primary side heating chamber 12 is a conductive, corrosive, or impurity-containing medium, the thermally conductive medium in the monitoring chamber 31 is different from the medium in the primary side heating chamber 12 and the medium in the heat exchanger 2.

[0042] The monitoring chamber 31 is provided with at least one of a filling port, an exhaust port, or a pressure detection port.

[0043] This allows the isolation cover to allow the heat from the medium in the primary heating chamber 12 to pass through the primary heat exchange wall 3, first heating the medium in the monitoring chamber 31, and then, through the heating medium in the monitoring chamber 31, heating the secondary heat exchange wall 21, and finally heating the liquid in the heat exchanger 2.

[0044] The above heating method can effectively prevent conductive media, electrolytes, corrosion products or electrode contaminants in the primary heating chamber 12 from entering the secondary heat exchange fluid circuit. At the same time, it makes the media maintenance, sewage discharge and online descaling operations of the primary heating chamber 12 independent of the feed water softening, desalination and gas phase medium quality control inside the heat exchanger 2. This achieves zoned management of scale sources, isolation of contaminants and decoupling of water treatment, thereby reducing the risk of cross-contamination, improving the cleanliness of the gas phase medium and extending the cleaning cycle of the heat exchanger 2.

[0045] Multiple detectors are installed in the monitoring cavity 31. The detectors can be fixedly connected to the side of the primary heat exchange wall 3 facing the secondary heat exchange wall 21, or the detectors can be fixedly connected to the outer wall of the heat exchange box 1. In this case, the probes on the detectors are fixedly inserted into the monitoring cavity 31.

[0046] The detector can be selected from one or more of the following: pressure sensor, liquid level sensor, circulating flow sensor, external liquid collection tank liquid level sensor, housing humidity sensor, or conductive detection plate. Here, the detector is for leak detection of heat exchange circuit.

[0047] When the primary heat exchange wall 3 and the secondary heat exchange wall 21 leak simultaneously or individually, the medium in the primary heating chamber 12 or the heat exchanger 2 will enter the monitoring chamber 31, causing changes in pressure, conductivity, and medium composition in the monitoring chamber 31. The detector can detect the problem and promptly feed it back to the existing control module to reduce power, cut off power, stop the pump, stop the water supply, or provide alarm protection.

[0048] The heat exchange box 1 is equipped with multiple detection units. The detection units can be selected from one or more of the following: pressure detection unit, liquid level detection unit, circulation flow detection unit, external liquid collection tank liquid level detection unit, outer shell humidity detection unit, conductive leakage detection plate or outer safety jacket. The detection unit here belongs to the external leakage detection of heat exchange box 1.

[0049] When a leak occurs in heat exchanger 1, these detection units can detect abnormal pressure drop, abnormal liquid level drop, abnormal circulation flow, or conductive leakage signals in the primary heating chamber 12, and transmit them to the existing control module to determine that there is a risk of leakage in the chamber, and then perform actions such as shutting off the high-pressure power supply, stopping the circulation pump, closing the inlet and outlet valves, and alarm protection.

[0050] Heat exchanger 2 can be selected from spiral coil heat exchangers, tube heat exchangers or plate heat exchangers, etc., according to actual working conditions.

[0051] The secondary heat exchange wall 21 and the primary heat exchange wall 3 are preferably made of metal materials that are pressure-resistant, corrosion-resistant and have high thermal conductivity, including one or more of stainless steel, nickel-based alloys, titanium alloys or composite metal materials.

[0052] The primary side heat exchange wall 3 is integrally formed on one side surface of the primary side heating cavity 12 with one or more of the following: turbulence fins, flow guide fins, and anti-scaling coating. By setting the turbulence structure, the heat medium in the primary side heating cavity 12 can be driven by these turbulence structures to flow in a deflected direction when passing through the isolation cover, thereby increasing the degree of turbulence, reducing the time for impurities to contact and adhere to the same position, enhancing the primary side convective heat transfer, and reducing local deposition in conjunction with the anti-scaling coating.

[0053] The inner wall of the heat exchanger 2 can be provided with a spiral flow channel, a micro-rib structure, or a segmented evaporation channel. The spiral flow channel causes the fluid to generate centrifugal swirling flow, driving the feed water to form a continuous thin liquid film tightly against the pipe wall. At the same time, it disturbs the fluid and regulates the flow trajectory, avoiding turbulent flow. The micro-ribs on the inner wall can further divide and refine the water film, providing dense vaporization nuclei, promoting the uniform generation of bubbles throughout the water body, and the bubbles can smoothly detach from the wall surface along the grooves between the ribs, preventing the gas film from adhering to the heat insulation, thereby promoting feed water film formation, uniform vaporization, and stable output of vapor-liquid two-phase flow.

[0054] Example 2 Please see Figure 3Based on Embodiment 1, the difference from Embodiment 1 is that the heat exchanger 2 provided in Embodiment 2 is a segmented tubular heat exchanger.

[0055] See Figures 3 to 5 , Figure 7 The tubular heat exchanger includes a preheating section 22 at the bottom, a boiling section 23 in the middle, and a vaporization section 24 at the top.

[0056] The connection between the preheating section 22, the boiling section 23 and the vaporization section 24 can be fixed by thread or integral molding.

[0057] When a tubular heat exchanger is assembled using threaded connections, it is easier to disassemble and install the internal structure of the tubular heat exchanger.

[0058] The diameters of the preheating section 22, boiling section 23, and vaporization section 24 increase progressively. The diameter of the preheating section 22 is smaller than that of the boiling section 23, and the diameter of the boiling section 23 is smaller than that of the vaporization section 24. The difference in diameter between two adjacent sections is no more than five millimeters.

[0059] The lengths of the preheating section 22, boiling section 23, and vaporization section 24 are specifically set according to actual temperature conditions and changes in the heating medium. This is just an example; for instance, based on the equipment's rated operating parameters, such as the feed water temperature, the saturation temperature corresponding to the working pressure, and the total hourly feed water mass flow rate, calculate the sensible heat required to heat the water from the inlet temperature to the saturation temperature, the latent heat of vaporization required for the saturated water to completely vaporize into a saturated gaseous medium, and the sensible heat required to heat the saturated gaseous medium to the target superheat temperature. Based on these calculations, rationally allocate the total heat exchange area (total heat exchange length) of the heat exchange walls, dividing the total heat exchange capacity into three equal parts and distributing them to the preheating, boiling, and vaporization sections.

[0060] When the liquid enters the preheating section 22, its flow rate increases due to the smallest diameter, resulting in stronger scouring of the inner wall of the tubular heat exchanger. This causes the liquid to rapidly heat up to near saturation temperature in the preheating section. When the liquid enters the boiling section 23, it begins to absorb heat and vaporize in large quantities, producing bubbles and forming a gas-liquid mixture with a significantly larger volume. The enlarged pipe diameter can accommodate this increased volume. Finally, the gas-liquid mixture with its increased volume enters the vaporization section 24, where it absorbs heat and vaporizes in large quantities, further increasing its volume. At this point, some liquid remains, but the further enlargement of the pipe diameter can accommodate the rapidly increasing vaporization, ensuring smooth flow.

[0061] Metal flexible hose section I25 is fixedly connected to both the bottom and top of the tubular heat exchanger, and threaded section I26 is fixedly connected to the end of the metal flexible hose section I25 away from the tubular heat exchanger.

[0062] This allows for a flexible connection between the two sides of the tubular heat exchanger, enabling the tubular heat exchanger to swing to a certain extent through the metal hose section I25, while ensuring that the metal hose section I25 does not leak during the swinging motion.

[0063] See Figures 3 to 5 , Figure 6 The isolation cover is fitted onto the outside of the tubular heat exchanger, and the shape of the isolation cover is the same as that of the tubular heat exchanger. The diameter of each segment of the isolation cover from bottom to top is larger than that of each segment of the tubular heat exchanger from bottom to top, so that the isolation cover can still completely cover the outside of the tubular heat exchanger to form the monitoring cavity 31.

[0064] Metal hose section II32 is fixedly connected to both the bottom and top of the isolation cover. A threaded section II33 is fixedly connected to the end of the metal hose section II32 away from the isolation cover, so that when the tubular heat exchanger swings, the outer isolation cover can also swing to a certain extent through the metal hose section II32 without affecting the movement of the tubular heat exchanger.

[0065] The diameter of metal flexible hose segment II32 is greater than the diameter of metal flexible hose segment I25.

[0066] Threaded section II33 is threaded onto the outside of threaded section I26. The bottom threaded section II33 is threadedly fixed to the bottom end of heat exchange box 1, and the bottom threaded section II33 penetrates the bottom end of heat exchange box 1. The top threaded section II33 is threadedly fixed to the bottom end of box cover 11, and the top threaded section II33 penetrates the bottom end of box cover 11.

[0067] The threaded section II33 can fix the inlet and outlet of the tubular heat exchanger, so that when the tubular heat exchanger swings, the liquid can still freely enter the tubular heat exchanger through the bottom inlet and enter the gas-liquid separator 5 through the top outlet without leakage. The threaded connection also improves the convenience of installation and disassembly.

[0068] See Figure 7 Springs 6 are movably connected in the three inner cavities of the tubular heat exchanger. The diameter of the springs 6 in the preheating section 22, boiling section 23 and vaporization section 24 increases progressively, and the difference between the progressively increasing diameters of the springs 6 is no more than 5 mm, preferably 3 mm.

[0069] This allows spring 6 to replace the spiral flow channel or micro-rib structure mentioned in Embodiment 1, reducing processing costs and processing difficulty. Spring 6 is also easier to install into the tubular heat exchanger and easier to remove.

[0070] Meanwhile, the fluid is continuously divided, diverted, and redirected by spring 6. Each turn of spring 6 forces the fluid to change its flow direction, eliminating long-distance straight laminar flow zones. In the preheating section 22, spring 6 continuously shears the water flow, disrupting the low-speed laminar flow layer on the pipe wall and forcing the water to adhere to the wall and stretch, forming a uniform thin water film. In the boiling section 23, spring 6 continuously impacts the bubbles on the pipe wall, breaking bubble aggregation and causing small bubbles to quickly detach from the wall surface, preventing them from forming a continuous insulating gas film. In the vaporization section 24, spring 6 disperses the continuous laminar flow of the gaseous medium, allowing the high-temperature gaseous medium to fully contact the heat exchange wall and eliminating localized stagnation zones in the gaseous medium.

[0071] Furthermore, due to the impact of the fluid, spring 6 will undergo slight elastic deformation. When the fluid load fluctuates, it can slightly change the flow channel gap to adapt to the volume expansion of water vapor. For example, under low flow and low pressure differential conditions, spring 6 contracts and the flow channel gap narrows, enhancing the wall disturbance of low-speed fluid. Under high flow and large-scale vaporization and expansion of water vapor, the fluid pressure differential expands spring 6 and the gap expands synchronously to adapt to the large specific volume flow requirements of two-phase gas and liquid and superheated gas phase media, and adaptively matches the changes in medium volume throughout the process.

[0072] The pitch of the springs 6 in the preheating section 22, boiling section 23 and vaporization section 24 increases progressively, and the difference in the pitch of the springs 6 in each progressively increasing stage is no more than 5 mm, preferably 2 mm.

[0073] For the preheating section 22, which uses small-diameter single-phase liquid water, a small-pitch spring 6 is used. The dense spring wires continuously divide the water flow, strengthen the flushing of the pipe wall, quickly form a uniform thin water film, and inhibit low-temperature scale deposition. For the boiling section 23, which uses medium-diameter two-phase vapor-liquid flow, a medium-pitch spring 6 is used. While retaining the ability to turbulently disperse bubbles, it provides sufficient gaps for bubbles to expand and detach from the pipe wall, preventing bubbles from accumulating and forming an insulating gas film. For the vaporization section 24, which uses large-diameter single-phase gaseous medium, a large-pitch spring 6 is used. This significantly reduces the flow resistance of the gaseous medium and simultaneously disturbs and disperses the laminar flow of the gaseous medium.

[0074] See Figures 5 to 7 At the junction of the preheating section 22 and the boiling section 23, an annular boss section 27 is threadedly fitted. The diameter of the boss section 27 is smaller than the diameter of the inner spring 6 in the preheating section 22. At the junction of the boiling section 23 and the vaporization section 24, another annular boss section 27 is threadedly fitted. The diameter of the boss section 27 is smaller than the diameter of the spring 6 in the boiling section 23.

[0075] The inner side of the boss section 27 has a regular hexagonal inner hole, which allows for the use of hexagonal bolts during installation. The hexagonal inner hole provides a force point, enabling the boss section 27 to rotate after being placed in the tubular heat exchanger. It is threadedly connected to the diameter change points of each section. Specifically, the top of the spring 6 in the preheating section 22 and boiling section 23 is fixedly connected to the upper nearest boss section 27, and the bottom of the spring 6 in the vaporization section 24 is fixedly connected to the lower nearest boss section 27. This allows the springs 6 in each section to be installed in their respective positions during the installation of the boss section 27, with one end of the spring 6 being fixed... The spring 6 is fixed so that when the liquid flow impacts the spring 6, the spring 6 at the top can compress and store energy, and the spring 6 at the bottom can stretch and store energy. Combined with the changes in liquid flow rate, impact force, and irregular bubble rupture, as well as the elastic force of the spring 6 itself, the spring 6 undergoes reciprocating deformation, thereby agitating the surrounding liquid, increasing the turbulent state, further disrupting the laminar flow layer on the tube wall, making the water film in the preheating section 22 thinner, and the bubble peeling speed in the boiling section 23 faster, thus improving the heat transfer coefficient. In addition, the reciprocating motion of the spring 6 will scrape the inner wall of the tubular heat exchanger, partially cleaning the scale.

[0076] See Figure 7 The spring 6 has multiple isolation protrusions 63 fixedly connected to the side of the inner wall of the tubular heat exchanger, which are made of wear-resistant material.

[0077] The isolation protrusion 63 is hemispherical, and the farthest point of the isolation protrusion 63 from the spring 6 is in contact with the inner wall of the tubular heat exchanger.

[0078] This design prevents the spring 6 from directly contacting the inner wall of the tubular heat exchanger. The isolation protrusion 63 expands the connection between the spring 6 and the inner wall, changing the line contact to a multi-point contact and creating multiple gaps. This ensures that the spring 6 does not detach from the tube wall and bounce, and also prevents damage to the liquid film formation. These gaps also prevent liquid accumulation at the point of direct contact between the spring 6 and the tube wall. When the fluid passes through the isolation protrusion 63 and the adjacent gaps, it generates micro-vortices, supplementing the additional disturbance near the wall. This causes the preheating section 22 to further thin the liquid film, and the boiling section 23 to assist in bubble stripping. Combined with the disturbance effect of the spiral gaps in the spring 6 itself, this improves the overall heat transfer coefficient.

[0079] Example 3 Please see Figure 8 Based on Embodiment 2, a guide groove 61 is provided on the bottom of the spring 6 facing the liquid impact, and the guide groove 61 is opened synchronously along the spiral of the spring 6.

[0080] This allows some of the liquid flow to be captured by the guide groove 61, causing the liquid flow to impact the guide groove 61 upwards, increasing the upward force on the spring 6 and enhancing the upward power of the spring 6.

[0081] The guide channel 61 is provided with multiple drainage channels 62 that pass through the spring 6. Each drainage channel 62 has three openings: the bottom opening of the drainage channel 62 is connected to the guide channel 61, the top opening passes through the spring 6, and the side opening is directly opposite the axis of the spring 6.

[0082] This allows the liquid in the guide channel 61 to be drained away through the discharge channel 62, preventing the accumulation of liquid in the guide channel 61. Furthermore, the discharge channel 62 guides the liquid flow to change direction and merge with other liquid flows, further improving the turbulence effect.

[0083] The guide channel 61 is inclined from bottom to top towards the axis of the spring 6, with the side opening facing the channel wall. The inclination angle is no more than 60 degrees, preferably 30 to 60 degrees. This allows the guide channel 61 to guide the liquid flow towards the axis of the spring 6, causing the liquid flow near the axis to be impacted and disturbed. This increases the tendency of the liquid flow at the center position to move towards the tube wall, preventing the liquid flow at the center position from remaining unchanged and unable to get close to the heat source to obtain a heating effect. At the same time, it enhances the reciprocating deformation of the spring 6, causing the spring 6 to transmit force to the tubular heat exchanger when deformed. This allows the tubular heat exchanger to oscillate slightly and quickly within a small range through the soft-limited metal hose section I25. The slight and rapid oscillation of the tubular heat exchanger causes the isolation cover to oscillate differently, thereby agitating the fluid in the primary heating chamber 12, improving the contact effect between the fluid in the primary heating chamber 12 and the isolation cover, and enhancing the heat exchange effect per unit time.

[0084] It should be noted that all of the above-mentioned structural connections are equipped with sealing rings to prevent media leakage.

Claims

1. An isolated heat exchange device with leakage monitoring function, characterized in that, It includes a heat exchange box (1) and a box cover (11), and a primary side heating chamber (12) is formed inside the heat exchange box (1). The heat exchange box (1) is provided with a plurality of sealed heat exchangers (2) in its inner cavity, and a sealed isolation cover is provided on the outside of the heat exchangers (2). The wall of the heat exchanger (2) forms a secondary heat exchange wall (21), and the wall of the isolation cover forms a primary heat exchange wall (3). A monitoring cavity (31) is formed between the secondary heat exchange wall (21) and the primary heat exchange wall (3). A detector is provided in the monitoring cavity (31), or a detector connected to the monitoring cavity (31) is configured to detect changes in pressure, conductivity, liquid level, humidity, flow rate or medium composition in the monitoring cavity (31) when leakage occurs in the primary heat exchange wall (3) and / or the secondary heat exchange wall (21). The spacing between the monitoring cavities (31) is no more than five millimeters, and the monitoring cavities (31) are filled with a heat-conducting medium.

2. The isolated heat exchange device with leakage monitoring function according to claim 1, characterized in that, Multiple heating rods (13) are provided at the bottom of the box cover (11). Multiple wall temperature sensors (14) are provided on the outer wall of the heat exchange box (1). A circulation pump (4) is provided on one side of the heat exchange box (1). The input end of the circulation pump (4) is connected to the bottom of the side of the primary heating chamber (12) near the heat exchanger (2). A two-way valve (41) is provided at the output end of the circulation pump (4). The output end of one side of the two-way valve (41) is connected to the top of the side of the primary heating chamber (12) near the heating rods (13). A water pump (42) is provided on one side of the heat exchange box (1). The output end of the water pump (42) is fixedly connected to the bottom input end of the heat exchanger (2). A gas-liquid separator (5) is provided on one side of the top of the box cover (11). The top output end of the heat exchanger (2) is fixedly connected to the input end of the gas-liquid separator (5).

3. The isolated heat exchange device with leakage monitoring function according to claim 1, characterized in that, The primary heat exchange wall (3) and / or the secondary heat exchange wall (21) are made of metal material. The primary heat exchange wall (3) has baffles and / or guide fins integrally formed on the surface facing the primary heating cavity (12), and / or the surface is coated with an anti-scaling coating.

4. The isolated heat exchange device with leakage monitoring function according to claim 1, characterized in that, The spacing of the monitoring chambers (31) is preferably 0.2 mm to 5 mm, and the heat-conducting medium in the monitoring chambers (31) is selected from one or more of the following: inert gas, high thermal conductivity insulating oil, composite medium of nano thermally conductive filler and gas, or low boiling point phase change working medium.

5. An isolated heat exchange device with leakage monitoring function according to claim 4, characterized in that, The heat exchanger (2) is a tubular heat exchanger, including a preheating section (22) at the bottom, a boiling section (23) in the middle and a vaporization section (24) at the top. The bottom and top of the tubular heat exchanger are provided with a metal flexible hose section I (25). The end of the metal flexible hose section I (25) away from the tubular heat exchanger is provided with a threaded section I (26). The tubular heat exchanger is provided with an agitator.

6. An isolated heat exchange device with leakage monitoring function according to claim 5, characterized in that, The stirring component includes two boss sections (27) located at the junction of the preheating section (22), the boiling section (23) and the vaporization section (24), and three springs (6) respectively located in the preheating section (22), the boiling section (23) and the vaporization section (24), wherein one end of the spring (6) near the boss section (27) is fixed to the boss section (27).

7. An isolated heat exchange device with leakage monitoring function according to claim 6, characterized in that, The spring (6) has multiple isolation protrusions (63) that fit the inner wall of the tube heat exchanger on one side. The spring (6) has a guide groove (61) at the bottom facing the liquid impact. The guide groove (61) has multiple through-spring grooves (62) that are inclined toward the axis.

8. An isolated heat exchange device with leakage monitoring function according to claim 7, characterized in that, The isolation cover is fitted onto the outside of the tubular heat exchanger. The bottom and top of the isolation cover are provided with metal flexible hose section II (32). The end of the metal flexible hose section II (32) away from the isolation cover is provided with threaded section II (33). The shape of the isolation cover is the same as that of the tubular heat exchanger. The diameter of each section of the isolation cover from bottom to top is greater than the diameter of each section of the tubular heat exchanger from bottom to top.

9. An isolated heat exchange device with leakage monitoring function according to claim 8, characterized in that, The diameter values ​​of the preheating section (22), boiling section (23) and vaporization section (24) increase progressively, and the diameter and pitch of the springs (6) in the preheating section (22), boiling section (23) and vaporization section (24) increase progressively.

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