Boiler blow-off heat energy recovery and storage device based on phase change material

Abstract

The invention relates to the technical field of boiler sewage cooling energy recovery devices, and discloses a boiler blow-off heat energy recovery and storage device based on a phase-change material, which comprises a heat energy recovery tower, the heat energy recovery tower is divided into an upper cavity, a heat storage and exchange cavity and a lower cavity, the upper cavity is arranged at the upper part of the heat energy recovery tower, and the lower cavity is arranged at the lower part of the heat energy recovery tower; a sewage inlet is fixedly formed in one side of the upper cavity, a heat storage and exchange cavity is formed in the bottom of the upper cavity, a filter screen is arranged between the upper cavity and the heat storage and exchange cavity, and a plurality of sets of heat exchange pipes are fixedly arranged in the heat storage and exchange cavity. According to the invention, the phase change material is introduced as an intermediate heat storage medium, so that the system can realize the transfer of heat energy in time and space, intermittent and unstable boiler blow-off waste heat can be stored in the phase change material, and when the boiler stops blow-off but a user needs heat, the waste heat is stably released and utilized; the problem that heat energy supply and demand time is mismatched in a traditional instant heat exchange mode is effectively solved, and the energy utilization efficiency is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of boiler wastewater cooling and energy recovery technology, specifically to a boiler wastewater heat recovery and storage device based on phase change materials. Background Technology

[0002] Industrial boilers require regular blowdowns during operation to remove high concentrations of dissolved solids and suspended impurities from the boiler water, ensuring steam quality and operational safety. This blowdown water, after flash evaporation in a blowdown expansion tank, still retains a relatively high temperature (typically close to 100°C) and contains a significant amount of usable low- to medium-grade heat energy. Directly discharging this high-temperature wastewater not only results in enormous energy waste and violates national energy conservation and emission reduction policies, but its thermal pollution also impacts municipal drainage networks and subsequent treatment facilities. Therefore, heat recovery and cooling of boiler blowdown water has become a crucial aspect of industrial energy conservation and emission reduction.

[0003] Currently, the industry generally uses traditional heat exchange technology to recover boiler blowdown heat energy, which involves installing shell-and-tube or plate heat exchangers to conduct instantaneous countercurrent heat exchange between cooling water and high-temperature blowdown wastewater. However, this "instantaneous heat exchange" mode has significant inherent drawbacks: First, boiler blowdown is an intermittent and short-term operation, while the process or domestic heat demand in the plant area is often continuous or asynchronous. This results in the heat exchanger being idle during non-blowdown periods, and the recovered heat energy not being utilized in a timely manner. Conversely, when heat energy is urgently needed, there is no heat to recover, causing a mismatch between heat energy supply and demand in time, leading to low recovery efficiency. Second, the blowdown wastewater contains a large amount of hardness ions and solid particles, which easily precipitate hard scale and deposit impurities on the heat exchange surface during the heat exchange process, rapidly reducing heat transfer efficiency, increasing flow resistance, requiring frequent shutdowns for manual cleaning and maintenance, resulting in high operating costs and affecting production continuity.

[0004] To address the aforementioned mismatch between heat supply and demand, existing technologies have introduced thermal storage devices, such as large hot water tanks for sensible heat storage. However, these systems are typically bulky and require a large area. Furthermore, due to the limited specific heat capacity of water, their thermal density is low, resulting in significant temperature drops and an inability to stably provide high-quality heat. More importantly, these existing thermal storage systems do not adequately consider the harsh conditions of boiler blowdown. When wastewater flows through complex thermal storage and exchange components, the scaling of calcium and magnesium ions and blockage by solid impurities become more severe, making it difficult to guarantee the reliability and long-term stability of the entire system. This leads to a huge workload for maintenance and severely limits its application and widespread adoption in the specific scenario of boiler blowdown. Summary of the Invention

[0005] In view of the shortcomings of existing boiler blowdown coolers mentioned in the background art, the present invention provides a boiler blowdown heat energy recovery and storage device based on phase change materials, which has the advantages of long service life and high heat energy recovery efficiency, and solves the technical problems mentioned in the background art such as easy damage to heat exchange tubes and scale affecting heat exchange efficiency.

[0006] This invention provides the following technical solution: a boiler blowdown heat energy recovery and storage device based on phase change materials, comprising a heat energy recovery tower, which is divided into three parts: an upper cavity, a heat storage and heat exchange chamber, and a lower cavity. The upper part of the heat energy recovery tower is the upper cavity, and a blowdown inlet is fixedly provided on one side of the upper cavity. The bottom of the upper cavity is the heat storage and heat exchange chamber, and a filter screen is provided between the upper cavity and the heat storage and heat exchange chamber. Multiple sets of heat exchange tubes are fixedly arranged inside the heat storage and heat exchange chamber, and the top ends of the heat exchange tubes are connected to... A collecting ring is installed on the outer wall of the top of the heat storage and heat exchange chamber. A water outlet is provided on one side of the collecting ring. A sealing plate is provided between the heat storage and heat exchange chamber and the lower chamber. The lower end of the heat exchange tube extends through the sealing plate into the lower chamber and is connected to a diverting ring at the lower end. A water inlet extending to the outside of the lower chamber is fixedly provided on one side of the diverting ring. A sludge outlet is fixedly provided at the bottom of the heat storage and heat exchange chamber. The heat storage and heat exchange chamber is filled with an intermediate heat storage material, which is located in the space surrounding the heat exchange tube.

[0007] Preferably, a discharge pipe is fixedly installed at the central axis of the heat recovery tower. The discharge pipe is a hollow pipe that extends to the outside of the recovery tower at its bottom and has a scale outlet fixedly installed at its end. A sleeve shaft is fixedly connected to the middle of the filter screen and is movably sleeved on the outside of the discharge pipe. A shaft spring is fixedly installed at the bottom of the sleeve shaft so that the sleeve shaft can drive the filter screen to move up and down along the discharge pipe. A scale suction port is opened on the sleeve shaft at the connection of the filter screen, a scale inlet is opened on the discharge pipe, and a suction pump is fixedly installed at the scale outlet.

[0008] Preferably, the filter screen is funnel-shaped, with a diameter consistent with the inner wall diameter of the recovery tower, and the movement range of the filter screen is not lower than the collection ring and not higher than the inlet.

[0009] Preferably, the sleeve shaft is provided with multiple sets of baffles evenly arranged at the bottom of the filter screen. The baffles are provided with flow guide ports. The baffles are provided with descaling ports for the heat exchange tubes to pass through. The descaling ports are provided with descaling plates that fit the outer wall of the heat exchange tubes. The sleeve shaft is provided with a suction port at the connection of the baffles.

[0010] Preferably, when no sewage passes through, the shaft spring pushes the sleeve shaft upward so that the suction port and the inlet port are in a directly opposite position. When the shaft spring moves downward and is compressed, the suction port and the inlet port are separated and thus closed.

[0011] Preferably, the baffle is funnel-shaped with the same angle as the filter screen, and the diameter of the baffle is the same as the diameter of the inner wall of the recovery tower.

[0012] Preferably, the positions of the guide ports on two adjacent sets of baffles are not directly opposite each other.

[0013] Preferably, the partition between the heat storage and heat exchange chamber and the lower chamber is configured as a funnel shape with the same angle as the baffle plate.

[0014] Preferably, a base plate is fixedly installed at the bottom of the heat recovery tower, and a support is fixedly installed around the base plate.

[0015] Preferably, the intermediate heat storage material is a phase change material, and the melting point of the phase change material is 60°C to 90°C.

[0016] The present invention has the following beneficial effects: 1. By introducing phase change materials as intermediate heat storage medium, this invention enables the system to transfer heat energy in time and space. It can store intermittent and unstable waste heat from boiler blowdown in phase change materials, and then release and utilize it stably when the boiler stops blowdown but users need heat. This effectively solves the problem of time mismatch between heat supply and demand in traditional instantaneous heat exchange mode and greatly improves energy utilization efficiency.

[0017] 2. This invention integrates the baffle plate, descaling plate, and heat storage cavity into a single design, enabling the system to automatically perform online descaling after each drainage cycle. When the water flow stops and the sleeve shaft resets under the action of the spring, the descaling plate on the baffle plate scrapes off the scale on the outer wall of the heat exchange tube and discharges it through the waste pipe. This automated process avoids a severe decrease in heat transfer efficiency due to scale accumulation, ensuring the long-term stable and efficient operation of the heat storage system and significantly reducing maintenance costs.

[0018] 3. This invention, through the installation of a filtration and descaling system consisting of a filter screen, a wastewater discharge pipe, and a suction pump, effectively filters wastewater before it enters the heat storage unit and automatically removes impurities during intermittent operation. This effectively prevents solid particles in the wastewater from impacting and abrading the heat exchange tubes, and avoids them mixing with the phase change material and affecting the heat storage performance. The system's self-cleaning capability eliminates filter screen clogging, ensuring a smooth filtration and heat exchange process, thereby comprehensively improving the reliability and service life of the entire equipment. Attached Figure Description

[0019] Figure 1 A schematic diagram of the overall structure of the invention; Figure 2 This is a vertical sectional view of the overall structure of the present invention; Figure 3 This is a vertical cross-sectional view of the lower cavity structure of the present invention; Figure 4 This is a schematic diagram of the internal structure of the waste discharge pipe of the present invention; Figure 5 This is a schematic cross-sectional view of the present invention in the state of impurity removal; Figure 6 This is a schematic diagram of the baffle structure of the present invention.

[0020] In the diagram: 1. Upper cavity; 2. Heat storage and exchange cavity; 3. Lower cavity; 31. Water inlet; 32. Diverter ring; 4. Sludge inlet; 5. Sludge outlet; 6. Heat exchange tube; 61. Water outlet; 62. Collector ring; 7. Support; 71. Base plate; 8. Waste discharge pipe; 81. Scale inlet; 82. Scale outlet; 83. Suction pump; 9. Shaft sleeve; 91. Filter screen; 92. Baffle plate; 93. Guide port; 94. Descaling port; 95. Suction port; 96. Shaft spring. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Please see Figure 1-2A boiler blowdown heat energy recovery and storage device based on phase change materials includes a heat recovery tower, which is divided into three parts: an upper chamber 1, a heat storage and exchange chamber 2, and a lower chamber 3. The upper part of the heat recovery tower is the upper chamber 1, and a blowdown inlet 4 is fixedly installed on one side of the upper chamber 1. The blowdown inlet 4 is connected to the outlet of the blowdown expansion tank to introduce the residual wastewater after flash evaporation into the heat recovery tower. The bottom of the upper chamber 1 is the heat storage and exchange chamber 2. A filter screen 91 is installed between the upper chamber 1 and the heat storage and exchange chamber 2. The diameter of the filter screen 91 is related to the recovery... The inner wall of the tower has a uniform diameter. A filter screen 91 filters the incoming wastewater. The wastewater enters the filter screen 91 through the inlet 4, where impurities are filtered out. This prevents solid impurities in the wastewater from impacting the heat exchange tubes 6 inside the heat storage and heat exchange chamber 2 during heat exchange, thus affecting their service life. Multiple sets of heat exchange tubes 6 are fixedly installed inside the heat storage and heat exchange chamber 2. The heat storage and heat exchange chamber 2 is filled with intermediate heat storage material, which is located in the space surrounding the heat exchange tubes 6. The wastewater in the heat storage and heat exchange chamber 2 fully contacts the heat exchange tubes 6. The heat exchange tube 6 performs heat exchange, further reducing the temperature of the discharged wastewater. Simultaneously, the heat energy is recovered and reused using the heat exchange tube 6. The top of the heat exchange tube 6 is connected to a collecting ring 62 located on the outer wall of the top of the heat storage and heat exchange chamber 2. An outlet 61 is located on one side of the collecting ring 62, allowing the heated water to be reused. The bottom of the heat storage and heat exchange chamber 2 is a lower chamber 3. A partition plate is installed between the heat storage and heat exchange chamber 2 and the lower chamber 3. The bottom end of the heat exchange tube 6 extends through the partition plate into the lower chamber 3 and is connected to a diversion ring 32 at its lower end. A water inlet 31 extending to the outside of the lower cavity 3 is fixedly provided on one side of the flow ring 32. Cooling water entering through the water inlet 31 is evenly fed into multiple sets of heat exchange tubes 6 from bottom to top through the flow ring 32, which makes the heat exchange efficiency between the cooling water and the sewage in the heat exchange tubes 6 higher. A sewage outlet 5 is fixedly provided at the bottom of the heat storage and heat exchange chamber 2. After filtration, impurity removal and heat exchange cooling, the sewage is discharged from the sewage outlet 5 for use. A base plate 71 is fixedly provided at the bottom of the heat recovery tower. A support 7 is fixedly provided around the base plate 71 to support and carry the recovery tower.

[0023] Please see Figure 3-4A waste discharge pipe 8 is fixedly installed at the central axis of the heat recovery tower. The waste discharge pipe 8 is a hollow pipe, extending to the outside of the recovery tower at its bottom, and a scale outlet 82 is fixedly installed at its end. A sleeve shaft 9 is fixedly connected to the middle of the filter screen 91 and is movably sleeved on the outside of the waste discharge pipe 8. A shaft spring 96 is fixedly installed at the bottom of the sleeve shaft 9, so that the sleeve shaft 9 can drive the filter screen 91 to move up and down along the waste discharge pipe 8. The movement range of the filter screen 91 is not lower than the collection ring 62 and not higher than the sewage inlet 4 to ensure the filtration effect of the filter screen 91. The filter screen 91 is designed in a funnel shape, so that solid impurities on the filter screen 91 roll off or are washed into the center of the filter screen 91 by the water flow and accumulate there, avoiding impurities. Accumulated wastewater buildup around the filter screen 91 causes blockage and affects the cooling and filtration rate. A suction port 95 is provided on the sleeve shaft 9 at the connection point of the filter screen 91, and a wastewater inlet 81 is provided on the discharge pipe 8. When no wastewater passes through, the shaft spring 96 pushes the sleeve shaft 9 upward so that the suction port 95 and the wastewater inlet 81 are in the same position. When the shaft spring 96 moves downward and compresses, the suction port 95 and the wastewater inlet 81 are separated and closed. A suction pump 83 is fixedly installed at the wastewater outlet 82. When the wastewater inlet 4 is closed, the suction port 95 and the wastewater inlet 81 are in the same position. The suction pump 83 is started to suction, so that the impurities accumulated in the center of the filter screen 91 are discharged through the wastewater discharge pipe 8.

[0024] Please see Figure 5 Multiple sets of baffles 92 are evenly arranged at the bottom of the filter screen 91 on the sleeve shaft 9. The diameter of the baffles 92 is the same as the diameter of the inner wall of the recovery tower. The baffles 92 are provided with guide ports 93. The positions of the guide ports 93 on two adjacent sets of baffles 92 are not directly opposite each other, thereby increasing the turbulence of sewage in the heat storage and heat exchange chamber 2 and preventing sewage from flowing directly through the center of the shell of the heat storage and heat exchange chamber 2, which would result in very little contact with the heat exchange tube 6 and lead to extremely low heat transfer efficiency. The baffles 92 are provided with descaling ports 94 corresponding to the heat exchange tube 6 for the heat exchange tube 6 to pass through. Descaling plates that fit the outer wall of the heat exchange tube 6 are provided at the descaling ports 94. When the sewage discharge ends and the sleeve shaft 9 moves upward and resets with the shaft spring 96, the baffles 92 move upward relative to the heat exchange tube 6, so that the descaling plates fit the outer wall of the heat exchange tube 6. The calcium and magnesium scale adsorbed on the outer wall of the heat exchange tube 6 is scraped off to prevent long-term scale accumulation from severely reducing the heat exchange efficiency of the heat exchange tube 6. The baffle plate 92 is funnel-shaped with the same angle as the filter screen 91. The sleeve shaft 9 also has a scale suction port 95 at the connection of the baffle plate 92. The discharge pipe 8 has a scale inlet 81 at the corresponding position. This ensures that when the suction pump 83 is started to suck up impurities after the sewage inlet is finished, the scale and impurities scraped off from the center of the baffle plate 92 on the heat exchange tube 6 are simultaneously sucked out and discharged. The partition between the heat storage heat exchange chamber 2 and the lower chamber 3 is set as a funnel-shaped partition with the same angle as the baffle plate 92. This allows the lowest set of baffle plates 92 to fit in close contact with the bottom partition of the heat storage heat exchange chamber 2, thereby completely scraping off the scale on all parts of the outer wall of the heat exchange tube 6.

[0025] Please see Figure 6 The heat exchange tube 6 can be set in a spiral shape to improve the heat exchange efficiency of sewage. At the same time, the corresponding descaling port 94 on the baffle plate 92 is set with the same spiral angle to adapt to the rotation of the heat exchange tube 6. When the sleeve shaft 9 moves along the discharge pipe 8, it moves spirally upward or spirally downward.

[0026] The working principle of the method of using this invention is as follows: When in use, the working process of this boiler blowdown waste heat phase change heat storage and recovery system is divided into three core stages: First, during the heat storage stage (when the boiler is blown out), the high-temperature wastewater from the boiler enters the upper chamber 1 of the heat recovery tower through the inlet 4 connected to the blowout expansion container. The wastewater first falls onto the filter screen 91 for preliminary filtration, where solid impurities are trapped. Subsequently, the wastewater flows downward into the heat storage and heat exchange chamber 2, which is filled with solid phase change material. At the same time, the heat storage circuit is activated, and a low-temperature heat carrier (such as demineralized water or antifreeze) is pumped in from the inlet 31, evenly distributed by the distribution ring 32, and flows upward through multiple sets of heat exchange tubes 6. Inside the heat storage and heat exchange chamber 2, the high-temperature wastewater transfers its heat to the phase change material surrounding the heat exchange tubes 6, causing it to absorb a large amount of latent heat and melt into a liquid state, thus stably storing the thermal energy. Simultaneously, the heat carrier inside the heat exchange tubes 6 is also heated, and the heated heat carrier flows into the collector ring 62 at the top, and is finally transported to the insulated storage tank through the outlet 61 for another form of storage. At this point, the heat energy of the wastewater has been effectively stored in the phase change material and the hot water in the insulated storage tank. The wastewater, after sufficient heat exchange and cooling, is discharged from the bottom outlet 5. During this process, the water flow pressure of the wastewater presses down on the filter screen 91 and the sleeve shaft 9 connected to it, compressing the shaft spring 96, causing the suction port 95 on the sleeve shaft 9 to be misaligned and closed with the inlet port 81 on the discharge pipe 8.

[0027] Secondly, during the heat extraction stage (when heat energy is needed), the system can operate as long as it has stored heat, regardless of whether the boiler is currently discharging wastewater. At this time, the valves are switched to activate the heat extraction circuit. Cold water from the user side is pumped in through inlet 31 and flows through heat exchange tube 6. After losing its heat source, the liquid phase change material begins to release latent heat into the cold water inside the tube, gradually solidifying and thus stably and continuously heating the cold water. The heated hot water is then supplied to the user through the manifold 62 and outlet 61. This process not only outputs the stored heat energy but also "charges" the phase change material, restoring it to a solid state and preparing it for the next heat storage cycle.

[0028] Finally, during the automatic cleaning phase (after each blowdown), when the boiler stops blowdown and no wastewater flows into the inlet 4, the system pressure drops, and the shaft spring 96 pushes the sleeve shaft 9 upward along the discharge pipe 8 to reset. This action produces two key effects: first, the upward movement of the sleeve shaft 9 realigns the suction port 95 with the inlet 81; second, the multi-layer baffle plate 92 fixed on the sleeve shaft 9 moves upward relative to the heat exchange tube 6, at which point the descaling plates installed in the descaling port 94 on the baffle plate 92 scrape off the scale adhering to the outer wall of the heat exchange tube 6. The scraped-off scale and impurities accumulated in the center of the filter screen 91 are drawn into the discharge pipe 8 through the aligned suction port 95 and inlet 81 under the negative pressure generated after the suction pump 83 starts, and finally discharged from the system through the outlet 82, thus achieving automated online cleaning without disassembly, ensuring that the system can maintain high-efficiency heat transfer performance for a long time.

[0029] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0030] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A boiler blowdown heat energy recovery and storage device based on phase change material, comprising a heat energy recovery tower, which is divided into an upper cavity (1), a heat storage and heat exchange cavity (2), and a lower cavity (3), characterized in that: The upper part of the heat recovery tower is an upper cavity (1), and a sewage inlet (4) is fixedly provided on one side of the upper cavity (1). The bottom of the upper cavity (1) is a heat storage and heat exchange chamber (2). A filter screen (91) is provided between the upper cavity (1) and the heat storage and heat exchange chamber (2). Multiple sets of heat exchange tubes (6) are fixedly provided in the heat storage and heat exchange chamber (2). The top end of the heat exchange tubes (6) is connected to a collection ring (62) provided on the outer wall of the top end of the heat storage and heat exchange chamber (2). A water outlet (61) is provided on one side of the collection ring (62). A partition is provided between the heat storage and heat exchange chamber (2) and the lower chamber (3). The lower end of the heat exchange tube (6) extends through the partition into the lower chamber (3) and is connected to a diversion ring (32) at the lower end. An inlet (31) extending to the outside of the lower chamber (3) is fixedly provided on one side of the diversion ring (32). A drain outlet (5) is fixedly provided at the bottom of the heat storage and heat exchange chamber (2). The heat storage and heat exchange chamber (2) is filled with intermediate heat storage material, which is located in the space around the heat exchange tube (6).

2. A PCM-based boiler blowdown heat recovery and storage device according to claim 1, wherein: A waste discharge pipe (8) is fixedly installed at the central axis of the heat recovery tower. The waste discharge pipe (8) is a hollow pipe, with its bottom extending to the outside of the recovery tower and a scale outlet (82) fixedly installed at its end. A sleeve shaft (9) is fixedly connected to the middle of the filter screen (91) and is movably sleeved on the outside of the waste discharge pipe (8). A shaft spring (96) is fixedly installed at the bottom of the sleeve shaft (9), so that the sleeve shaft (9) can drive the filter screen (91) to move up and down along the waste discharge pipe (8). A scale suction port (95) is opened on the sleeve shaft (9) at the connection of the filter screen (91). A scale inlet (81) is opened on the waste discharge pipe (8). A suction pump (83) is fixedly installed at the scale outlet (82).

3. A PCM-based boiler blowdown heat recovery and storage device according to claim 1, wherein: The filter screen (91) is funnel-shaped, and its diameter is the same as the inner wall diameter of the recovery tower. The movement range of the filter screen (91) is not lower than the collection ring (62) and not higher than the sewage inlet (4).

4. A PCM-based boiler blowdown heat recovery and storage device according to claim 2, wherein: The sleeve shaft (9) is located at the bottom of the filter screen (91) and multiple sets of baffles (92) are evenly arranged. The baffles (92) are provided with flow guides (93). The baffles (92) are provided with descaling ports (94) for the heat exchange tube (6) to pass through. The descaling ports (94) are provided with descaling plates that match the outer wall of the heat exchange tube (6). The sleeve shaft (9) is provided with a suction port (95) at the connection of the baffles (92).

5. A PCM-based boiler blowdown heat recovery and storage device according to claim 2, wherein: When no sewage passes through, the shaft spring (96) pushes the sleeve shaft (9) upward so that the suction port (95) and the inlet port (81) are in the same position. When the shaft spring (96) moves downward and is compressed, the suction port (95) and the inlet port (81) are separated and thus closed.

6. A PCM-based boiler blowdown heat recovery and storage device according to claim 4, wherein: The baffle plate (92) is funnel-shaped with the same angle as the filter screen (91), and the diameter of the baffle plate (92) is the same as the diameter of the inner wall of the recovery tower.

7. The latent heat recovery and storage device for boiler blowdown according to claim 1, wherein: The opening positions of the guide ports (93) on the two adjacent sets of baffles (92) are not directly opposite each other.

8. The latent heat recovery and storage device for boiler blowdown according to claim 1, wherein: The sealing plate between the heat storage and heat exchange cavity (2) and the lower cavity (3) is funnel-shaped and has the same angle as the flow baffle (92).

9. The latent heat recovery and storage device for boiler blowdown according to claim 1, wherein: The heat energy recovery tower is fixedly provided with a bottom plate (71) at the bottom, and the periphery of the bottom plate (71) is fixedly provided with a support (7).

10. The phase change material based boiler blowdown heat recovery and storage apparatus of claim 1, wherein: The intermediate heat storage material is a phase change material, and the melting point of the phase change material is 60-90 DEG C.

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