Vacuum heat exchange system

Abstract

The invention discloses a vacuum heat exchange system, belongs to the technical field of heat exchangers, solves the problem that in the prior art, flue gas temperature fluctuation is difficult to effectively utilize, and mainly adopts the technical scheme that the vacuum heat exchange system comprises a plate heat exchanger and a tubular heat exchanger, a first flowing cavity used for allowing fluid to be subjected to heat exchange to flow is formed in the heat exchange pipe, a second flowing cavity used for allowing fluid to be subjected to heat exchange to flow is formed in the heat exchange pipe, the upper end of the first flowing cavity is connected with the upper side of the heat exchange channel through a first pipeline, and the lower side of the heat exchange channel is connected with the lower end of the first flowing cavity through a backflow pipe. And the adjusting assembly is used for adjusting the liquid level height of the phase change material in the first flowing cavity. The flue gas heat exchanger is mainly used for achieving efficient heat exchange when the flue gas temperature fluctuates, and heat in flue gas is efficiently utilized.

Description

Technical Field

[0001] This application relates to the technical field of heat exchangers, in particular to a vacuum heat exchange system. Background Art

[0002] In the existing vacuum heat exchange system, when the heat exchange tubes are used for heat exchange in flue gas, the heat exchange efficiency is often low due to insufficient contact area. Usually, the solution is to add a threaded ring on the outer surface of the heat exchange tubes to increase the contact surface with the flue gas. However, this also causes dust in the flue gas to accumulate on the leeward side of the threaded ring, resulting in corrosion of the heat exchange tubes at the threaded ring, and thus leakage of the phase change material in the heat exchange tubes. In view of such technical problems, setting a corrugated heat exchange plate on the flue gas side for heat exchange treatment can effectively solve the problem of corrosion of the heat exchanger on the flue gas side. However, due to the large number of welding points of the heat exchange plate and leakage caused by pressure fluctuations during the heat exchange between the heat exchange fluids to be treated, the heat exchange tubes are used for heat exchange in the heat exchange fluids to be treated.

[0003] During the heat exchange process of the liquid phase change material in the heat exchange plate, the temperature of the flue gas fluctuates. When encountering high-temperature flue gas, a large amount of the liquid phase change material will undergo a phase change, generating a large amount of gaseous phase change material, resulting in a rapid reduction of the liquid phase change material in the heat exchange plate. However, if the heat exchange efficiency of the heat exchange tubes does not increase accordingly, the heat exchange efficiency of the flue gas will drop sharply, causing a waste of a large amount of heat in the flue gas. Currently, the existing technology usually solves this problem by improving the heat exchange efficiency at the heat exchange tubes, specifically by adjusting the water inlet and outlet rates of the heat exchange tubes in real time, or maintaining a relatively fast water inlet and outlet speed all the time. However, both of these methods will greatly increase the operating power of the tubular heat exchanger. Summary of the Invention

[0004] In order to overcome the deficiency in the existing technology that it is difficult to effectively utilize the flue gas when the temperature of the flue gas fluctuates, this application provides a vacuum heat exchange system, which can achieve efficient heat exchange when the temperature of the flue gas fluctuates and efficiently utilize the heat in the flue gas.

[0005] In order to achieve the above-mentioned purpose, the present application adopts the following technical scheme: a vacuum heat exchange system, including a plate heat exchanger and a tube heat exchanger, the plate heat exchanger is provided with a plurality of heat exchange plates arranged at intervals, a flue for flue gas circulation is formed between the heat exchange plates, a first flow cavity is provided in the heat exchange plate, a phase change material is provided in the first flow cavity, the tube heat exchanger is provided with a plurality of heat exchange tubes arranged at intervals, a heat exchange channel for flowing phase change material is formed between the heat exchange tubes, a second flow cavity for flowing the fluid to be exchanged is provided in the heat exchange tube, the upper end of the first flow cavity is connected to the upper side of the heat exchange channel through a first pipe, and the lower side of the heat exchange channel is connected to the lower end of the first flow cavity through a reflux pipe, and an adjustment component is provided between the tube heat exchanger and the plate heat exchanger, and the adjustment component is used to adjust the liquid level of the phase change material in the first flow cavity.

[0006] After adopting the above technical solution, when the flue gas flows in the flue, the heat is transferred to the heat exchange plate, and then the phase change material in the first flow cavity absorbs heat and changes phase into gas. The gaseous phase change material enters the upper side of the heat exchange channel through the first pipe from the upper end of the first flow cavity of the plate heat exchanger, and exchanges heat with the fluid to be exchanged in the heat exchange tube in the heat exchange channel. After releasing heat, the gaseous phase change material changes back to liquid phase change material, flows down along the side wall of the heat exchange channel, and returns to the lower end of the first flow cavity through the reflux pipe, completing the circulation of the phase change material. The fluid to be exchanged absorbs the heat of the phase change material in the second flow cavity, and the temperature rises, thereby realizing the heating or temperature-raising treatment of the fluid to be exchanged. Through such a design, the heat transfer between the flue gas, the phase change material and the fluid to be exchanged is realized, and the purpose of heat exchange is achieved. The present application has the following advantages: by setting a plate heat exchanger and a tube heat exchanger, and using an adjustment component to adjust the liquid level of the phase change material in the first flow cavity to always be higher than or equal to the height of the flue, the size of the space where the liquid phase change material is located can be flexibly adjusted according to the fluctuation of the flue gas temperature, so that liquid phase change materials of different volumes can cover the range that the flue gas can reach, and achieve efficient heat exchange when the flue gas temperature fluctuates differently, effectively utilize the heat in the flue gas, and avoid the waste of heat caused by excessively high flue gas temperature. On the other hand, the system allows the gaseous phase change material to enter the heat exchange channel from the upper side of the first pipe, and the liquid phase change material to flow out from the lower side of the heat exchange channel from the return pipe, so that the flow paths of the gaseous phase change material and the liquid phase change material are relatively independent, avoiding the gaseous phase change material from cooling down due to contact with the liquid phase change material during the flow process or the gaseous phase change material dissolving into the liquid phase change material, thereby ensuring the heat exchange efficiency of the flue gas to the fluid to be exchanged.

[0007] Further, the reflux pipe includes a second pipe and a third pipe. The adjusting assembly includes a water collecting tank and a linear actuator disposed on one side of the water collecting tank. The movable end of the linear actuator is adapted to the inner diameter of the water collecting tank. The lower end of the first flow chamber is connected to the water collecting tank through the second pipe, and the lower side of the heat exchange channel is connected to the water collecting tank through the third pipe. By gradually moving the movable end into the interior of the water collecting tank, the space where the liquid phase change material is located is reduced, thereby increasing the liquid level height of the phase change material in the first flow chamber.

[0008] With the foregoing technical solution, by gradually moving the movable end of the linear actuator into the interior of the water collecting tank, the liquid phase change material in the water collecting tank can be squeezed, reducing the space it occupies, so as to squeeze the liquid phase change material back into the first flow chamber, and then flexibly increase the liquid level height of the phase change material in the first flow chamber. In this way, according to the fluctuation of the actual flue gas temperature, the position and volume of the liquid phase change material can be accurately adjusted to ensure that it is always higher than or equal to the height of the flue, so that the liquid phase change material with different volumes can cover the range that the flue gas in the flue can reach, ensuring efficient heat exchange. Moreover, the combination of the water collecting tank and the linear actuator has a relatively simple structure, which is easy to implement and maintain. The linear actuator can provide a stable driving force and accurately control the movement of the movable end, thereby reliably adjusting the liquid level height of the liquid phase change material and ensuring the stability and reliability of the system.

[0009] Further, the reflux pipe includes a second pipe and a third pipe. The adjusting assembly includes a water collecting tank, an adjusting water pipe and a water level actuator. The lower end of the adjusting water pipe is communicated with the water collecting tank, and the upper end of the adjusting water pipe is communicated with the upper side of the heat exchange channel. The adjusting side of the water level actuator is disposed in the adjusting water pipe. Sliding valve plates are provided upstream and downstream of the adjusting side in the adjusting water pipe. An adjusting liquid is provided in the adjusting water pipe between the two sliding valve plates, so that the adjusting side of the water level actuator transports the adjusting liquid to the downstream, causing the sliding valve plates upstream and downstream to slide downstream, thereby increasing the liquid level height of the phase change material in the first flow chamber.

[0010] With the foregoing technical solution, by the water level actuator transporting the adjusting liquid to the downstream and causing the upstream and downstream sliding valve plates to slide downstream, the pressure and flow rate changes in the adjusting water pipe can be accurately controlled, and then the liquid level of the liquid phase change material in the water collecting tank can be accurately adjusted, and finally the accurate control of the liquid level height of the phase change material in the first flow chamber can be achieved. This accurate control can better adapt to various fluctuations of the flue gas temperature, ensure that the liquid phase change material can always accurately cover the range that the flue gas in the flue can reach, improve the heat exchange efficiency, and avoid heat waste.

[0011] Further, one end of the downstream sliding valve plate contacts the liquid phase change material, and the other end contacts the regulating liquid. One end of the upstream sliding valve plate contacts the gaseous phase change material, and the other end contacts the regulating liquid. When the upstream and downstream sliding valve plates move towards the liquid phase change material, the space occupied by the liquid phase change material is reduced, and the space occupied by the gaseous phase change material is increased.

[0012] With the foregoing technical solution, by changing the space of the liquid and gaseous phase change materials through the movement of the sliding valve plate, it can better adapt to the state changes of the phase change material under different temperature conditions. When the flue gas temperature rises and a large amount of the liquid phase change material undergoes phase change to generate more gaseous phase change materials, the sliding valve plate moves towards the liquid phase change material, increasing the space occupied by the gaseous phase change material, providing more accommodation space for the gaseous phase change material, and avoiding excessive pressure caused by insufficient space, which affects the normal operation of the system and the heat exchange efficiency. Dynamically adjusting the space according to the amounts of the gaseous and liquid phase change materials helps to optimize the heat exchange process. When the flue gas temperature is high, increasing the space of the gaseous phase change material enables the gaseous phase change material to have more sufficient space to exchange heat with the fluid to be heat-exchanged in the heat exchange tube, improving the efficiency and effect of heat exchange; while when the flue gas temperature is low, reducing the space of the gaseous phase change material and relatively increasing the space of the liquid phase change material allows more liquid phase change materials to participate in absorbing the heat of the flue gas, thereby improving the adaptability of the system to flue gas at different temperatures and the overall heat exchange performance.

[0013] Further, a water level sensor consistent with the height of the flue is provided in the third pipeline. When the liquid level height of the phase change material in the first flow chamber is higher than or equal to the height of the flue, the driver pauses working; when the liquid level height of the phase change material in the first flow chamber is lower than the height of the flue, the water level sensor transmits the water level signal to the driver, and the driver controls the execution module to work, so as to reduce the space where the liquid phase change material is located, and further raise the liquid level height of the phase change material in the first flow chamber to be higher than or equal to the height of the flue.

[0014] With the foregoing technical solution, by providing a water level sensor consistent with the height of the flue in the third pipeline, the liquid level height of the phase change material in the first flow chamber can be monitored in real time. When the liquid level height changes, the water level sensor can promptly transmit the water level signal to the driver, and the driver then controls the execution module to work, achieving automatic and precise control of the liquid level height of the phase change material. Without manual intervention, it improves the intelligence level and control precision of the system, ensures that the liquid level height is always maintained at an ideal state higher than or equal to the height of the flue, and thus guarantees efficient heat exchange.

[0017] Further, the diameter of the third pipeline is larger than that of the first pipeline and the number of the third pipelines is less than that of the first pipelines; the diameter of the third pipeline is larger than that of the second pipeline and the number of the third pipelines is less than that of the second pipelines.

[0018] Adopting the foregoing technical solution, the diameter of the third pipe is larger than that of the first pipe and the second pipe, which can provide a more spacious channel for the flow of the phase change material in the third pipe, reduce the flow resistance of the fluid, and make the flow of the liquid phase change material in the pipe smoother. At the same time, the number of the third pipes is relatively small. On the premise of ensuring the fluid flow rate, the pipe layout can be simplified, avoiding the pipes being too dense and complex, which is beneficial to the overall structure design and installation and maintenance of the system. Reducing the number of the third pipes and adopting pipes with a larger diameter can reduce the usage amount of pipe materials and processing costs on the premise of ensuring the system performance. In addition, the smaller number of pipes also means reducing the use of pipe connection components and seals, further reducing the manufacturing cost and maintenance cost of the system.

[0019] Furthermore, the heat exchange plate is formed by welding two thin plates with welding wires, so that the first flow chamber is divided into several mutually isolated heat exchange chambers by the welding wires.

[0020] Adopting the foregoing technical solution, in the prior art, the heat exchange plate is welded by solder joints or solder rings, which will cause multiple starting solder joints and stopping solder joints when the welding equipment is welding, resulting in multiple arc starting and arc stopping. And there will be thousands of solder joints or solder rings on a single heat exchange plate, which makes the heat exchange plate prone to weak bad points due to improper welding during the manufacturing process. This makes the heat exchange plate easy to be damaged due to the impact of particles in the flue gas during use. In this design, the heat exchange plate is welded by welding wires, so that the finished product rate of the heat exchange plate during welding processing is higher, and the first flow chamber is divided into several mutually isolated heat exchange chambers, increasing the contact area between the phase change material and the fluid (flue gas) outside the heat exchange plate. It can make the phase change material absorb the heat in the flue gas more fully and transfer the heat to the fluid to be heat exchanged more efficiently, thereby improving the heat exchange efficiency.

[0021] Furthermore, the return pipe includes a second pipe connecting the lower end of the first flow chamber and the water collecting tank. One second pipe is correspondingly connected to each heat exchange chamber, and the second pipes are interconnected through the water collecting tank so that the heat exchange chambers correspondingly connected by the second pipes are interconnected with each other.

[0022] With the foregoing technical solution, each heat exchange chamber is connected to the water collecting tank through a corresponding second pipeline, enabling the liquid phase change material to flow and exchange freely between different heat exchange chambers. During actual operation, since the flue gas temperature and flow rate at different positions may vary, this will result in different degrees of heat absorption by the phase change material in each heat exchange chamber. And this connection design enables the liquid phase change material to be adjusted between each heat exchange chamber, balancing the temperature and heat distribution of each heat exchange chamber. For example, when the flue gas temperature at the location of a certain heat exchange chamber is relatively high, the liquid phase change material evaporates quickly and the liquid level drops, the liquid phase change material in other heat exchange chambers will flow into this heat exchange chamber through the water collecting tank and the second pipeline, ensuring that there is sufficient liquid phase change material in each heat exchange chamber to participate in heat exchange, thereby improving the uniformity and efficiency of heat exchange of the entire plate heat exchanger.

[0023] Further, a housing for sleeving outside the heat exchange tube is provided on the tubular heat exchanger, an interface communicating with the heat exchange channel is provided on the housing, and an air extraction device is detachably connected to the interface.

[0024] With the foregoing technical solution, reducing the air pressure in the heat exchange channel can cause the phase change material to undergo a phase change at a lower boiling point. Thus, at the same heat source temperature, the phase change material can absorb heat more quickly and change from a liquid state to a gaseous state, accelerating the phase change process, and further improving the heat exchange efficiency of the entire system. The gaseous phase change material can exchange heat with the fluid to be heat-exchanged more rapidly, making the heat transfer more efficient. And since there are multiple heat exchange plates in the plate heat exchanger, only one such interface needs to be provided on the tubular heat exchanger, which is more convenient than setting multiple interfaces on the plate heat exchanger. Moreover, when pumping out the internal gas, the space of the heat exchange channel of the tubular heat exchanger is larger than the space of the first flow chamber inside the plate heat exchanger, and a larger pumping rate can be used during air extraction, avoiding the phenomenon of sharp contraction of the plate when pumping air in the plate heat exchanger. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present application will be further described below with reference to the drawings: Figure 1 is a schematic diagram of a vacuum heat exchange system of the present application; Figure 2 is Figure 1 the left view of; Figure 3 is a cross-sectional view of the water collecting tank in Embodiment 2; Figure 4 is a cross-sectional view of the tubular heat exchanger in Embodiment 2; Figure 5 is a cross-sectional view of the water collecting tank in Embodiment 1.

[0026] Description of the Drawings: 1. Plate heat exchanger; 11. Heat exchange plate; 12. Flue; 13. First flow chamber; 14. First pipe; 2. Tube heat exchanger; 21. Heat exchange tube; 22. Heat exchange channel; 23. Second flow chamber; 3. Return pipe; 31. Second pipe; 32. Third pipe; 4. Adjustment assembly; 41. Water collection tank; 42. Linear actuator; 421. Moving end; 43. Water level actuator; 431. Adjusting side; 44. Adjusting water pipe; 441. First section; 442. Second section; 443. Arc section; 45. Sliding valve plate; 5. Water level sensor; 6. Interface. Detailed Implementation Modes

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part rather than all of the embodiments of this application.

[0028] The terms "first", "second", etc. (if any) in the description and claims of this application are used to distinguish similar objects rather than to describe a specific order or sequence. Even if "second" is used to distinguish a certain technical feature, it does not necessarily imply the existence of "first". It should be understood that in this application, "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. It should be understood that in this application, "a plurality of" means two or more. "And / or" is merely a description of the association relationship between associated objects, indicating that three relationships may exist. For example, X and / or Y may represent: X exists alone, X and Y exist simultaneously, and Y exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "Including X, Y, and Z" and "including X, Y, Z" mean that all of X, Y, and Z are included. "Including X, Y, or Z" means including any one of X, Y, and Z. "Including X, Y, and / or Z" means including any one or any two or all three of X, Y, and Z.

[0029] The technical solutions of this application will be described in detail below with specific embodiments. These specific embodiments can be combined or replaced according to the actual situation. For the same or similar concepts or processes, they may not be repeated in some embodiments.

[0030] Embodiment 1: As Figures 1 to 4As shown, the present application provides a vacuum heat exchange system, including a plate heat exchanger 1 and a tube heat exchanger 2, wherein the plate heat exchanger 1 is provided with a plurality of heat exchange plates 11 arranged at intervals, and a flue 12 for flue gas circulation is formed between the heat exchange plates 11, and a first flow cavity 13 is provided in the heat exchange plate 11, and a phase change material is provided in the first flow cavity 13, and a plurality of heat exchange tubes 21 arranged at intervals are provided in the tube heat exchanger 2, and a heat exchange channel 22 for flowing the phase change material is formed between the heat exchange tubes 21, and a second flow cavity 23 for flowing the fluid to be heat exchanged is provided in the heat exchange tube 21, and the upper end of the first flow cavity 13 is connected to the upper side of the heat exchange channel 22 through a first pipe 14, and the lower side of the heat exchange channel 22 is connected to the lower end of the first flow cavity 13 through a reflux pipe 3, and an adjustment component 4 is provided between the tube heat exchanger 2 and the plate heat exchanger 1, and the adjustment component 4 is used to adjust the liquid level of the phase change material in the first flow cavity 13.

[0031] After adopting the above technical solution, when the flue gas flows in the flue 12, the heat is transferred to the heat exchange plate 11, and then the phase change material in the first flow cavity 13 absorbs heat and changes phase into gas. The gaseous phase change material enters the upper side of the heat exchange channel 22 from the upper end of the first flow cavity 13 of the plate heat exchanger 1 through the first pipe 14, and exchanges heat with the fluid to be exchanged in the heat exchange tube 21 in the heat exchange channel 22. After releasing heat, the gaseous phase change material changes back to liquid phase change material, flows down along the side wall of the heat exchange channel 22, and returns to the lower end of the first flow cavity 13 through the return pipe 3, completing the circulation of the phase change material. The fluid to be exchanged absorbs the heat of the phase change material in the second flow cavity 23, and the temperature rises, thereby achieving the heating or temperature-raising treatment of the fluid to be exchanged. Through such a design, the heat transfer between the flue gas, the phase change material and the fluid to be exchanged is realized, and the purpose of heat exchange is achieved. The present application has the following advantages: by setting a plate heat exchanger 1 and a tube heat exchanger 2, and using the regulating component 4 to adjust the liquid level of the phase change material in the first flow cavity 13 to always be higher than or equal to the height of the flue 12, the size of the space where the liquid phase change material is located can be flexibly adjusted according to the fluctuation of the flue gas temperature, so that the liquid phase change material under different volumes can cover the range that the flue gas in the flue 12 can reach, and achieve efficient heat exchange when the flue gas temperature fluctuates differently, effectively utilize the heat in the flue gas, and avoid the waste of heat generated when the flue gas temperature is too high. On the other hand, the system allows the gaseous phase change material to enter from the upper side of the heat exchange channel 22 from the first pipe 14, and the liquid phase change material to flow out from the lower side of the heat exchange channel 22 from the return pipe 3, so that the flow paths of the gaseous phase change material and the liquid phase change material are relatively independent, avoiding the gaseous phase change material from cooling down due to contact with the liquid phase change material during the flow process or the gaseous phase change material dissolving into the liquid phase change material, thereby ensuring the heat exchange efficiency of the flue gas to the fluid to be exchanged.

[0032] Furthermore, a housing for sleeving outside the heat exchange tubes 21 is provided on the tubular heat exchanger 2. An interface 6 communicating with the heat exchange channel 22 is provided on the housing, and an air extraction device is detachably connected to the interface.

[0033] By adopting the foregoing technical solution, reducing the air pressure in the heat exchange channel 22 can cause the phase change material to undergo a phase change at a lower boiling point. Thus, at the same heat source temperature, the phase change material can absorb heat more quickly and change from a liquid state to a gaseous state, accelerating the phase change process, and further improving the heat exchange efficiency of the entire system. The gaseous phase change material can exchange heat with the fluid to be heat-exchanged more rapidly, making the heat transfer more efficient. Moreover, since the heat exchange plates 11 of the plate heat exchanger 1 have multiple first flow chambers 13, multiple interfaces are required to achieve synchronous air extraction. However, only one such interface 6 needs to be provided on the tubular heat exchanger 2, which is more convenient than the multiple interfaces required on the plate heat exchanger 1. When extracting the internal gas, the space of the heat exchange channel 22 of the tubular heat exchanger 2 is larger than the space of the first flow chambers 13 inside the plate heat exchanger 1, and a larger extraction rate can be used during air extraction, avoiding the phenomenon of rapid contraction of the plate sheets during air extraction in the plate heat exchanger 1.

[0034] Preferably, a vacuum pump is equipped at the interface to maintain the vacuum degree of the space where the phase change material is located, ensuring that the phase change material can undergo a phase change at a low temperature. Phase change material can also be injected into it through the interface.

[0035] Specifically, the phase change material can be one of materials such as freon, ethanol, acetone, water, etc.; the liquid level height of the phase change material in the initial state is greater than or equal to the height of the heat exchange plate 11 in the flue 12, so that the phase change material can better contact the flue gas for heat conduction, and can also prevent the dry burning of the heat exchange plate 11.

[0036] As Figures 1 to 4 shown, the return pipe 3 includes a second pipe 31 and a third pipe 32. The adjusting assembly 4 includes a water collecting tank 41, an adjusting water pipe 44, and a water level driver 43. The lower end of the adjusting water pipe 44 communicates with the water collecting tank 41, the upper end of the adjusting water pipe 44 communicates with the upper side of the heat exchange channel 22, the adjusting side 431 of the water level driver 43 is arranged in the adjusting water pipe 44, and sliding valve plates 45 are arranged upstream and downstream of the adjusting side 431 in the adjusting water pipe 44. An adjusting liquid is arranged in the adjusting water pipe 44 between the two sliding valve plates 45, so that the adjusting side 431 of the water level driver 43 transports the adjusting liquid to the downstream, causing the sliding valve plates 45 upstream and downstream to both slide downstream, thereby raising the liquid level height of the phase change material in the first flow chamber 13.

[0037] Adopting the foregoing technical solution, the regulating liquid is transported by the water level driver 43 to the downstream of the regulating water pipe 44 where the water level driver 43 is located. At this time, the water volume in the upstream of the regulating water pipe 44 decreases, and the water volume in the downstream increases. Thereby, the pressure exerted by the gaseous phase change material on the upstream sliding valve plate 45 can overcome the gravity of the liquid phase change material in the regulating water pipe 44, the gravity of the upstream sliding valve plate 45, and the frictional force between the upstream sliding valve plate 45 and the regulating water pipe 44, so as to drive the upstream sliding valve plate 45 to slide upward, that is, the upstream and downstream sliding valve plates 45 slide downstream together, and the downstream sliding valve plate 45 can push the liquid phase change material out of the regulating water pipe 44, so that the outflowing liquid phase change material flows into the first flow chamber 13, and finally realizes the precise control of the liquid level height of the phase change material in the first flow chamber 13. This precise control can better adapt to various fluctuations of the flue gas temperature, ensure that the liquid phase change material can always accurately cover the range that the flue gas in the flue 12 can reach, improve the heat exchange efficiency, and avoid heat waste.

[0038] Specifically, the water level driver 43 can be a device such as a water pump for transporting the regulating liquid, and the regulating side 431 is the water inlet and outlet of the water pump.

[0039] Furthermore, one end of the downstream sliding valve plate 45 contacts the liquid phase change material, and the other end contacts the regulating liquid. One end of the upstream sliding valve plate 45 contacts the gaseous phase change material, and the other end contacts the regulating liquid. When the upstream and downstream sliding valve plates 45 move towards the liquid phase change material, the space where the liquid phase change material is located is reduced, and the space where the gaseous phase change material is located is increased.

[0040] Adopting the foregoing technical solution, by changing the space sizes of the liquid and gaseous phase change materials through the movement of the sliding valve plate 45, it can better adapt to the state changes of the phase change material under different temperature conditions. When the flue gas temperature rises and a large amount of the liquid phase change material undergoes phase change to generate more gaseous phase change materials, the sliding valve plate 45 moves towards the liquid phase change material, increasing the space where the gaseous phase change material is located, providing more accommodation space for the gaseous phase change material, and avoiding excessive pressure caused by insufficient space, which affects the normal operation of the system and the heat exchange efficiency. Dynamically adjusting the space according to the amounts of the gaseous and liquid phase change materials helps to optimize the heat exchange process. When the flue gas temperature is relatively high, increasing the space of the gaseous phase change material enables the gaseous phase change material to have more sufficient space to exchange heat with the fluid to be heat-exchanged in the heat exchange tube 21, improving the efficiency and effect of heat exchange; while when the flue gas temperature is relatively low, reducing the space of the gaseous phase change material and relatively increasing the space of the liquid phase change material can enable more liquid phase change materials to participate in absorbing the heat of the flue gas, thereby improving the adaptability of the system to flue gas at different temperatures and the overall heat exchange performance.

[0041] Specifically, the regulating water pipe 44 includes a first section 441 connected to the upper side of the water collecting tank 41, a second section 442 connected to the upper side of the heat exchange channel, and an arc section 443 connecting the first section 441 and the second section 442. The second section 442 is located above the tubular heat exchanger 2 and extends upward; the first section 441 is located in the water collecting tank 41 and extends upward; the arc section 443 is connected to the upper ends of the first section 441 and the second section 442, so that the regulating liquid flows in the regulating water pipe 44. Even if the gaseous phase change material becomes a liquid phase change material after entering the second section 442, it can flow back to the heat exchange channel 22 along the side wall of the regulating water pipe 44 and then return to the third pipe 32. Wherein, when the liquid level in the first flow chamber 13 is too high, the water level driver 43 can be reversely started to work, and the regulating liquid is transported to the upstream of the regulating water pipe 44 through the water level driver 43. At this time, the water volume in the downstream of the regulating water pipe 44 decreases, and the water volume in the upstream increases, so that the sliding valve plates 45 in the upstream and downstream slide upstream together, increasing the space volume where the liquid phase change material is located and reducing the space volume where the gaseous phase change material is located, so that the liquid level in the first flow chamber 13 decreases.

[0042] Further, a water level sensor 5 having the same height as the flue 12 is provided in the third pipe 32. When the liquid level height of the phase change material in the first flow chamber 13 is higher than or equal to the height of the flue 12, the water level driver 43 pauses working; when the liquid level height of the phase change material in the first flow chamber 13 is lower than the height of the flue 12, the water level sensor 5 transmits a water level signal to the water level driver 43, and the water level driver 43 controls the execution module to work, so that the space where the liquid phase change material is located is reduced, and further the liquid level height of the phase change material in the first flow chamber 13 is raised to be higher than or equal to the height of the flue 12.

[0043] By adopting the foregoing technical solution, by providing the water level sensor 5 having the same height as the flue 12 in the third pipe 32, the liquid level height of the phase change material in the first flow chamber 13 can be monitored in real time. When the liquid level height changes, the water level sensor 5 can timely transmit the water level signal to the water level driver 43, and the water level driver 43 then controls the execution module to work, realizing automatic and precise control of the liquid level height of the phase change material. Without manual intervention, the intelligent level and control precision of the system are improved, ensuring that the liquid level height always maintains an ideal state higher than or equal to the height of the flue 12, thereby ensuring efficient heat exchange.

[0044] Specifically, the execution module refers to the above-mentioned regulating side 431.

[0045] Further, the diameter of the third pipe 32 is larger than that of the first pipe 14 and the number of the third pipes 32 is less than that of the first pipes 14; the diameter of the third pipe 32 is larger than that of the second pipe 31 and the number of the third pipes 32 is less than that of the second pipes 31.

[0046] Adopting the foregoing technical solution, the diameter of the third pipe 32 is larger than that of the first pipe 14 and the second pipe 31, which can provide a wider channel for the flow of the phase change material in the third pipe 32, reduce the flow resistance of the fluid, and make the flow of the liquid phase change material in the pipe smoother. At the same time, the number of the third pipes 32 is relatively small. On the premise of ensuring the fluid flow rate, the pipe layout can be simplified, avoiding overly dense and complex pipes, which is beneficial to the overall structural design and installation and maintenance of the system. Reducing the number of the third pipes 32 and using pipes with a larger diameter can reduce the usage amount of pipe materials and processing costs on the premise of ensuring the system performance. In addition, the smaller number of pipes also means reducing the use of pipe connection components and seals, further reducing the manufacturing cost and maintenance cost of the system.

[0047] Furthermore, the heat exchange plate 11 is formed by welding two thin plates with welding wires, so that the first flow chamber 13 is divided into several mutually isolated heat exchange chambers by the welding wires.

[0048] Adopting the foregoing technical solution, the heat exchange plate 11 in the prior art is welded by solder joints or welding rings, which will cause multiple starting and stopping points during welding by the welding equipment, resulting in multiple arcing and stopping arcs. And there will be thousands of solder joints or welding rings on a single heat exchange plate 11, which makes the heat exchange plate 11 prone to weak bad points due to improper welding during the manufacturing process. This makes the heat exchange plate 11 prone to damage due to the impact of particles in the flue gas during use. However, in this design, the heat exchange plate 11 is welded by welding wires, which makes the finished product rate of the heat exchange plate 11 higher during welding processing, and divides the first flow chamber 13 into several mutually isolated heat exchange chambers, increasing the contact area between the phase change material and the fluid (flue gas) outside the heat exchange plate 11. It can enable the phase change material to absorb the heat in the flue gas more fully and transfer the heat to the fluid to be heat exchanged more efficiently, thereby improving the heat exchange efficiency.

[0049] Furthermore, the return pipe 3 includes a second pipe 31 connecting the lower end of the first flow chamber 13 and the water collecting tank 41. One second pipe 31 is correspondingly connected to each heat exchange chamber, and the second pipes 31 are interconnected through the water collecting tank 41, so that the heat exchange chambers correspondingly connected by the second pipes 31 are interconnected with each other.

[0050] Adopting the foregoing technical solution, each heat exchange chamber is connected to the water collecting tank 41 through the corresponding second pipeline 31, enabling the liquid phase change material to freely flow and exchange between different heat exchange chambers. During actual operation, since the flue gas temperature and flow rate at different positions may vary, this will result in different degrees of heat absorption by the phase change material in each heat exchange chamber. And this connection design enables the liquid phase change material to be adjusted between each heat exchange chamber, balancing the temperature and heat distribution of each heat exchange chamber. For example, when the flue gas temperature at the position of a certain heat exchange chamber is relatively high, the liquid phase change material evaporates quickly and the liquid level drops, the liquid phase change material in other heat exchange chambers will flow into this heat exchange chamber through the water collecting tank 41 and the second pipeline 31, ensuring that each heat exchange chamber has sufficient liquid phase change material to participate in heat exchange, thereby improving the uniformity and efficiency of heat exchange of the entire plate heat exchanger 1.

[0051] Embodiment 2: The difference between this embodiment and Embodiment 1 lies in the different drive used and there is no need to adopt the regulating water pipe 44. As Figure 5 shown, the reflux pipe 3 includes a second pipeline 31 and a third pipeline 32, the regulating assembly 4 includes a water collecting tank 41 and a linear actuator 42 provided on one side of the water collecting tank 41. The movable end 421 of the linear actuator 42 is adapted to the inner diameter of the water collecting tank 41. The lower end of the first flow chamber 13 is connected to the water collecting tank 41 through the second pipeline 31, and the lower side of the heat exchange channel 22 is connected to the water collecting tank 41 through the third pipeline 32. The movable end 421 gradually moves into the water collecting tank 41, so that the space where the liquid phase change material is located is reduced, thereby raising the liquid level height of the phase change material in the first flow chamber 13.

[0052] Adopting the foregoing technical solution, by gradually moving the movable end 421 of the linear actuator 42 into the water collecting tank 41, the liquid phase change material in the water collecting tank 41 can be squeezed, reducing the space where it is located, so as to squeeze the liquid phase change material back into the first flow chamber 13, and then flexibly raise the liquid level height of the phase change material in the first flow chamber 13. In this way, according to the fluctuation of the actual flue gas temperature, the position and volume of the liquid phase change material can be accurately adjusted to ensure that it is always higher than or equal to the height of the flue 12, realizing that the liquid phase change material with different volumes can cover the range that the flue gas in the flue 12 can reach, ensuring efficient heat exchange. And the combination of the water collecting tank 41 and the linear actuator 42 is adopted, with a relatively simple structure, easy to implement and maintain. The linear actuator 42 can provide a stable driving force, accurately control the movement of the movable end 421, so as to reliably adjust the liquid level height of the liquid phase change material and ensure the stability and reliability of the system.

[0053] Furthermore, the water level sensor 5 adopted in this embodiment is as Figure 1As shown, a water level sensor 5 with the same height as the flue 12 is provided in the third pipe 32. When the liquid level height of the phase change material in the first flow chamber 13 is higher than or equal to the height of the flue 12, the linear actuator 42 pauses working. When the liquid level height of the phase change material in the first flow chamber 13 is lower than the height of the flue 12, the water level sensor 5 transmits a water level signal to the linear actuator 42, and the linear actuator 42 controls the execution module to work, so as to reduce the space where the liquid phase change material is located, and then raise the liquid level height of the phase change material in the first flow chamber 13 to be higher than or equal to the height of the flue 12.

[0054] By adopting the foregoing technical solution, by arranging the water level sensor 5 with the same height as the flue 12 in the third pipe 32, the liquid level height of the phase change material in the first flow chamber 13 can be monitored in real time. When the liquid level height changes, the water level sensor 5 can timely transmit the water level signal to the linear actuator 42, and the linear actuator 42 then controls the execution module to work, realizing the automatic and precise control of the liquid level height of the phase change material. Without manual intervention, the intelligent degree and control precision of the system are improved, ensuring that the liquid level height is always maintained in an ideal state higher than or equal to the height of the flue 12, thus ensuring efficient heat exchange.

[0055] Specifically, the execution module refers to the movable end 421 described above.

[0056] Furthermore, the diameter of the third pipe 32 is larger than that of the first pipe 14 and the number of the third pipes 32 is less than that of the first pipes 14; the diameter of the third pipe 32 is larger than that of the second pipe 31 and the number of the third pipes 32 is less than that of the second pipes 31.

[0057] In addition to the above preferred embodiments, the present application has other implementation manners. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection requested by the present application.

Claims

1. A vacuum heat exchange system, characterized in that, It includes a plate heat exchanger and a tubular heat exchanger. A plurality of heat exchange plates are arranged at intervals inside the plate heat exchanger. A flue for flowing flue gas is formed between the heat exchange plates. A first flow cavity is arranged inside the heat exchange plate, and a phase change material is arranged inside the first flow cavity. A plurality of heat exchange tubes are arranged at intervals inside the tubular heat exchanger. A heat exchange channel for flowing the phase change material is formed between the heat exchange tubes. A second flow cavity for flowing the fluid to be heat exchanged is arranged inside the heat exchange tube. The upper end of the first flow cavity is connected to the upper side of the heat exchange channel through a first pipeline. The lower side of the heat exchange channel is connected to the lower end of the first flow cavity through a return pipe. An adjusting component is arranged between the tubular heat exchanger and the plate heat exchanger, and the adjusting component is used to adjust the liquid level height of the phase change material inside the first flow cavity.

2. The vacuum heat exchange system according to claim 1, wherein, The return pipe includes a second pipeline and a third pipeline. The adjusting component includes a water collecting tank and a linear driver arranged on one side of the water collecting tank. The movable end of the linear driver is adapted to the inner diameter of the water collecting tank. The lower end of the first flow cavity is connected to the water collecting tank through the second pipeline. The lower side of the heat exchange channel is connected to the water collecting tank through the third pipeline. The movable end moves gradually into the water collecting tank to reduce the space where the liquid phase change material is located, thereby raising the liquid level height of the phase change material inside the first flow cavity.

3. A vacuum heat exchange system according to claim 1, characterized in that, The return pipe includes a second pipeline and a third pipeline. The adjusting component includes a water collecting tank, an adjusting water pipe and a water level driver. The lower end of the adjusting water pipe is communicated with the water collecting tank. The upper end of the adjusting water pipe is communicated with the upper side of the heat exchange channel. The adjusting side of the water level driver is arranged inside the adjusting water pipe. Sliding valve plates are arranged upstream and downstream of the adjusting side inside the adjusting water pipe. An adjusting liquid is arranged inside the adjusting water pipe between the two sliding valve plates. The adjusting side of the water level driver transports the adjusting liquid to the downstream, causing the sliding valve plates upstream and downstream to slide downstream, thereby raising the liquid level height of the phase change material inside the first flow cavity.

4. A vacuum heat exchange system according to claim 3, characterized in that, One end of the sliding valve plate downstream contacts the liquid phase change material, and the other end contacts the adjusting liquid. One end of the sliding valve plate upstream contacts the gaseous phase change material, and the other end contacts the adjusting liquid. When the sliding valve plates upstream and downstream move towards the liquid phase change material, the space where the liquid phase change material is located is reduced, and the space where the gaseous phase change material is located is increased.

5. A vacuum heat exchange system according to claim 2 or 3, characterized in that, A water level sensor with the same height as the flue is arranged inside the third pipeline. When the liquid level height of the phase change material inside the first flow cavity is higher than or equal to the height of the flue, the driver suspends operation. When the liquid level height of the phase change material inside the first flow cavity is lower than the height of the flue, the water level sensor transmits a water level signal to the driver, and the driver controls the execution module to work, so as to reduce the space where the liquid phase change material is located, thereby raising the liquid level height of the phase change material inside the first flow cavity to be higher than or equal to the height of the flue.

6. A vacuum heat exchange system according to claim 2 or 3, characterized in that, The diameter of the third pipeline is larger than that of the first pipeline and the number of the third pipelines is less than that of the first pipelines; the diameter of the third pipeline is larger than that of the second pipeline and the number of the third pipelines is less than that of the second pipelines.

7. A vacuum heat exchange system according to claim 2 or 3, characterized in that, The heat exchange plate is formed by welding two thin plates with welding wires, so that the first flow cavity is divided into several mutually isolated heat exchange cavities by the welding wires.

8. A vacuum heat exchange system according to claim 7, characterized in that, The reflux pipe includes a second pipe connecting the lower end of the first flow chamber and the water collecting tank. One second pipe is correspondingly connected to the heat exchange chamber, and the second pipes are interconnected through the water collecting tank so that the heat exchange chambers correspondingly connected by the second pipes are interconnected with each other.

9. A vacuum heat exchange system according to claim 1, wherein, A housing for sleeving outside the heat exchange tube is provided on the tubular heat exchanger. An interface communicating with the heat exchange channel is provided on the housing, and an air extraction device is detachably connected to the interface.

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