Boiler blow-off heat energy recovery device

Abstract

The utility model relates to the technical field of heat recovery, in particular to a boiler blow-off heat energy recovery device which solves the technical problems that a traditional boiler waste heat recovery system is limited in recovery efficiency, waste heat recovery is insufficient easily, and heat energy is wasted, and the boiler blow-off heat energy recovery device comprises a plate heat exchanger and a first box body. A second box body is arranged on the outer side of the top of the first box body and communicates with the first box body through a connecting pipe. A heat recovery part and a fifth box body are arranged in the first box body; the fifth box body is communicated with the first box body through a plurality of smoke holes uniformly distributed in the side wall of the fifth box body; a plurality of lattice heat storage bricks are arranged in each of the first box body and the second box body; and the heat recovery part absorbs heat in the flue gas and heats water in the flue gas. Flue gas heat can be absorbed through the lattice heat storage bricks, and heat energy is stored to stabilize temperature fluctuation of the system; by combining the multi-stage heat exchange design of heat removal sewage heat exchange and flue gas heat exchange, waste heat of sewage and flue gas discharged by the boiler is effectively utilized.

Description

A boiler blowdown heat recovery device Technical Field

[0001] This utility model relates to the field of heat recovery technology, and in particular to a boiler blowdown heat energy recovery device. Background Technology

[0002] A gas-fired boiler is a boiler equipment that uses natural gas, city gas, liquefied petroleum gas or biogas as fuel. It heats water or produces steam by burning gas and is widely used in heating, bathing, industrial steam supply and other fields. According to statistics, the exhaust water temperature of small and medium-sized boilers can reach 150-180℃, and the flue gas temperature is generally 120-150℃. If it is discharged directly, a lot of heat energy will be wasted.

[0003] Traditional boiler waste heat recovery systems typically rely on a single heat exchange structure, such as only wastewater exchanging heat with cold water or only flue gas exchanging heat with cold water. This limits recovery efficiency and can easily lead to insufficient waste heat recovery, resulting in energy waste. Summary of the Invention

[0004] To overcome the technical defects of traditional boiler waste heat recovery systems, which have limited recovery efficiency and are prone to insufficient waste heat recovery, resulting in heat energy waste, this utility model provides a boiler blowdown heat energy recovery device.

[0005] This utility model provides a boiler blowdown heat energy recovery device, including a plate heat exchanger and a first housing; a second housing is arranged on the outer side of the top of the first housing, and a copper pipe runs through the second housing. The two ends of the copper pipe are respectively connected to a first water supply pipe and a second water supply pipe. The other end of the second water supply pipe is connected to the cold fluid inlet of the plate heat exchanger. The second housing is connected to the first housing via a connecting pipe, and a one-way valve is installed on the connecting pipe to allow flue gas to flow from the first housing to the second housing. An exhaust pipe is also connected to the top of the second housing. A heat recovery component and a fifth housing are arranged inside the first housing. The heat recovery component has a third connector and a fourth connector that penetrate the side wall of the first housing. The outer end of the third connector is connected to a water supply pipe inlet, and the other end of the water supply pipe inlet is connected to the boiler's water inlet. The first and second boxes are connected together. The fourth joint is connected to a water supply pipe outlet at its outer end, and the other end of the water supply pipe outlet is connected to the cold fluid outlet of the plate heat exchanger. The fifth box is connected to the first box through multiple flue holes evenly distributed on its side wall. The fifth box is connected to a fifth joint that penetrates the side wall of the first box. The outer end of the fifth joint is connected to a flue gas inlet pipe, which is connected to the flue gas outlet of the boiler. Multiple grid heat storage bricks are installed in both the first and second boxes. The heat recovery component absorbs heat from the flue gas and heats the water inside. The hot fluid inlet of the plate heat exchanger is fixedly connected to a first drain pipe, and the hot fluid outlet of the plate heat exchanger is connected to a second drain pipe. The first drain pipe is connected to the boiler's wastewater discharge pipe, and the second drain pipe is used to discharge the wastewater after heat exchange.

[0006] A plate heat exchanger is a device consisting of multiple metal heat transfer plates with a certain corrugated shape arranged at certain intervals, sealed around the perimeter by gaskets, and overlapped and pressed together by a frame and a clamping screw. The four corner holes of the plates and gaskets form the distribution pipes and collection pipes of the fluid, while also reasonably separating the cold fluid and the hot fluid, allowing them to flow in the flow channels on both sides of each metal heat transfer plate and exchange heat through the metal heat transfer plate.

[0007] In this invention, the first drain pipe is connected to the boiler's wastewater discharge pipe. The wastewater flows into the plate heat exchanger through the first drain pipe and the hot fluid inlet. After the heat in the wastewater is absorbed, it is discharged from the hot fluid outlet through the second drain pipe. The second water supply pipe is connected to the plate heat exchanger's cold fluid inlet. The second water supply pipe introduces preheated water from the outside or directly introduces cold water, depending on the system configuration. The water inlet of the second water supply pipe absorbs the heat from the wastewater in the plate heat exchanger and then flows out from the plate heat exchanger's cold fluid outlet. The cold fluid outlet of the plate heat exchanger is connected to the first housing via a water supply outlet pipe, which is used to transport the heated water into the first housing for further heat recovery.

[0008] The first chamber is connected to the boiler's flue gas outlet via an inlet pipe. High-temperature flue gas exits from the fifth chamber inside the first chamber, passes through the heat recovery components in the first chamber, and then flows to the second chamber through a connecting pipe at the top of the first chamber. After passing through the second chamber, the high-temperature flue gas exits through its exhaust pipe at the top. Water entering the first chamber from the feedwater outlet absorbs heat from the high-temperature flue gas as it passes through the heat recovery components. This further heat-absorbing water flows out from the feedwater inlet and finally into the boiler's inlet for use. Copper pipes in the second chamber connect the first and second feedwater pipes. The heat from the high-temperature flue gas is further absorbed by the water in the copper pipes, effectively preheating the cold fluid in the plate heat exchanger.

[0009] The grid-type thermal storage bricks in the first and second chambers can fully absorb the heat from the high-temperature flue gas and store thermal energy to stabilize system temperature fluctuations.

[0010] Preferably, the heat recovery component includes a third housing, multiple serpentine pipes, and a fourth housing. The third and fourth housings are fixed to the bottom and top of the inner side of the first housing, respectively. The multiple serpentine pipes are connected between the third and fourth housings to connect them. The fourth housing is connected to a fourth connector, and the third housing is connected to a third connector. The serpentine pipes typically consist of multiple sections of round pipe elbows and multiple straight pipes. The sections of round pipe elbows are not on the same plane, and the inlet and outlet centerlines of the round pipe elbows are parallel but have an eccentricity. Different orientations can be achieved by adjusting the number of sections (e.g., two or more sections) and parameters (e.g., height, bending radius). The straight pipes connect the multiple sections of round pipe elbows to form the entire serpentine pipe. Water from the feedwater outlet first flows into the fourth housing, then is diverted through the multiple serpentine pipes and finally converges in the third housing. The converged water then flows into the boiler from the feedwater inlet. The water in each serpentine tube can exchange heat with the high-temperature flue gas in the first chamber, maximizing the recovery of heat from the high-temperature flue gas.

[0011] Preferably, the grid-type heat storage bricks in the first housing are inserted between adjacent serpentine tubes and fixed to the bottom of the first housing; the grid-type heat storage bricks in the second housing are located below the steel pipes and fixed to the bottom of the second housing. Because the high-temperature flue gas can spread to every corner of the first and second housings, placing the grid-type heat storage bricks between adjacent serpentine tubes ensures the absorption of heat from the high-temperature flue gas between the adjacent serpentine tubes, storing thermal energy to stabilize system temperature fluctuations.

[0012] Compared with the prior art, the technical solution provided by this utility model has the following technical effects: The grid heat storage bricks installed in the first and second boxes can absorb the heat of flue gas and store thermal energy to stabilize the system temperature fluctuations. This heat storage design helps to maintain the stable operation of the boiler system and reduce the impact of temperature fluctuations on system performance. By combining the heat exchange design of wastewater and flue gas, the waste heat of the wastewater and flue gas discharged from the boiler is effectively utilized. The wastewater transfers heat to the cold water through the heat exchanger. At the same time, the flue gas exchanges heat with the water flow through the serpentine tube in the first box. The flue gas also preheats the cold water in the second box, further increasing the water temperature. This multi-stage heat exchange method significantly improves the waste heat recovery efficiency and reduces energy waste. Attached Figure Description

[0013] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the present invention and, together with the description, serve to explain the principles of the present invention.

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 is a schematic diagram of the overall structure of a boiler blowdown heat energy recovery device according to a certain embodiment of the present invention;

[0016] Figure 2 is a schematic diagram of the front connection structure of the first box and the second box in a certain embodiment of the present invention;

[0017] Figure 3 is a schematic diagram of the rear connection structure of the first box and the second box in a certain embodiment of the present invention;

[0018] Figure 4 is a schematic diagram of the internal structure of the first box and the second box in a certain embodiment of the present invention;

[0019] Figure 5 is a schematic diagram of the structure of the heat recovery component in the first box in a certain embodiment of this utility model.

[0020] In the diagram: 1. Plate heat exchanger; 2. First water supply pipe; 3. Second water supply pipe; 4. First drain pipe; 5. Water supply outlet pipe; 6. Second drain pipe; 7. Water supply inlet pipe; 8. Flue gas inlet pipe; 9. Second housing; 10. First housing; 11. Connecting pipe; 12. One-way valve; 13. Third housing; 14. Checker bricks; 15. Fourth housing; 16. Fifth housing; 17. Serpentine tube; 18. Copper tube; 19. Flue gas exhaust pipe; 20. Third connector; 21. Fourth connector; 22. Flue gas outlet; 23. Fifth connector. Detailed Implementation

[0021] To better understand the above-mentioned objectives, features, and advantages of this utility model, the solution of this utility model will be further described below. It should be noted that, unless otherwise specified, the embodiments of this utility model and the features thereof can be combined with each other.

[0022] In this description, it should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. It should also be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joint" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0023] Many specific details are set forth in the following description in order to provide a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the present invention, and not all embodiments.

[0024] The specific embodiments of this utility model will be described in detail below with reference to Figures 1 to 5.

[0025] In one embodiment, as shown in Figure 1, a boiler blowdown heat recovery device is disclosed, including a plate heat exchanger 1 and a first housing 10; a second housing 9 is provided on the outer side of the top of the first housing 10, and a copper pipe 18 passes through the second housing 9. The two ends of the copper pipe 18 are respectively connected to a first water supply pipe 2 and a second water supply pipe 3. The other end of the second water supply pipe 3 is connected to the cold fluid inlet of the plate heat exchanger 1. The second housing 9 is connected to the first housing 10 through a connecting pipe 11. A one-way valve 12 is installed on the connecting pipe 11 to allow flue gas to flow from the first housing 10 to the second housing 9. A flue gas pipe 19 is also connected to the top of the second housing 9; a heat recovery component and a fifth housing 16 are provided inside the first housing 10; the heat recovery component is provided with a third connector 20 and a fourth connector 21 that penetrate the side wall of the first housing 10. The outer end of the third connector 20 is connected to a water supply pipe inlet 7. The other end is connected to the boiler inlet. The outer end of the fourth connector 21 is connected to the feed water outlet 5. The other end of the feed water outlet 5 is connected to the cold fluid outlet of the plate heat exchanger 1. The fifth box 16 is connected to the first box 10 through multiple flue holes 22 evenly distributed on its side wall. The fifth box 16 is connected to the fifth connector 23 that penetrates the side wall of the first box 10. The outer end of the fifth connector 23 is connected to the flue gas inlet pipe 8. The flue gas inlet pipe 8 is connected to the flue gas outlet of the boiler. Multiple grid heat storage bricks 14 are provided in both the first box 10 and the second box 9. The heat recovery component absorbs the heat in the flue gas and heats the water inside it. The hot fluid inlet of the plate heat exchanger 1 is fixedly connected to the first drain pipe 4. The hot fluid outlet of the plate heat exchanger 1 is connected to the second drain pipe 6. The first drain pipe 4 is connected to the boiler's wastewater discharge pipe. The second drain pipe 6 is used to discharge the wastewater after heat exchange.

[0026] The plate heat exchanger 1 is a device consisting of multiple metal heat transfer plates with a certain corrugated shape arranged at certain intervals, sealed around the perimeter by gaskets, and overlapped and pressed together by a frame and a clamping screw. The four corner holes of the plates and gaskets form the distribution pipe and the collection pipe of the fluid, while also reasonably separating the cold fluid and the hot fluid, allowing them to flow in the flow channels on both sides of each metal heat transfer plate and exchange heat through the metal heat transfer plate.

[0027] In this invention, the first drain pipe 4 is connected to the boiler's wastewater discharge pipe. The wastewater flows into the plate heat exchanger 1 through the first drain pipe 4 and the hot fluid inlet of the plate heat exchanger 1. After the heat in the wastewater is absorbed, it is discharged from the hot fluid outlet through the second drain pipe 6. The second water supply pipe 3 is connected to the cold fluid inlet of the plate heat exchanger 1. The second water supply pipe 3 introduces preheated water from the outside or directly introduces cold water, depending on the system configuration. The water inlet of the second water supply pipe 3 absorbs the heat from the wastewater in the plate heat exchanger 1 and flows out from the cold fluid outlet of the plate heat exchanger 1. The cold fluid outlet of the plate heat exchanger 1 is connected to the first housing 10 by a water supply outlet pipe 5. The water supply outlet pipe 5 is used to transport the heated water into the first housing 10 for further heat recovery.

[0028] The first chamber 10 is connected to the boiler's flue gas outlet via the inlet pipe 8. High-temperature flue gas exits from the fifth chamber 16 inside the first chamber 10. After passing through the heat recovery components in the first chamber 10, it flows from the connecting pipe 11 at the top of the first chamber 10 to the second chamber 9. After passing through the second chamber 9, the high-temperature flue gas exits from the exhaust pipe 19 at its top. Water discharged into the first chamber 10 from the feedwater outlet pipe 5 absorbs heat from the high-temperature flue gas as it passes through the heat recovery components. The further heat-absorbing water flows out from the feedwater inlet pipe 7 and finally into the boiler's inlet for use. A copper pipe 18 installed in the second chamber 9 connects the first feedwater pipe 2 and the second feedwater pipe 3. The heat from the high-temperature flue gas is further absorbed by the water in the copper pipe 18, effectively preheating the cold fluid in the plate heat exchanger 1.

[0029] The grid-type heat storage bricks 14 in the first chamber 10 and the second chamber 9 can fully absorb the heat in the high-temperature flue gas and store thermal energy to stabilize the system temperature fluctuations.

[0030] Based on the above embodiments, in a preferred embodiment, the heat recovery component includes a third housing 13, multiple serpentine tubes 17, and a fourth housing 15. The third housing 13 and the fourth housing 15 are respectively fixed to the bottom and top of the inner side of the first housing 10. The multiple serpentine tubes 17 are respectively connected between the third housing 13 and the fourth housing 15 to connect them. The fourth housing 15 is connected to the fourth connector 21, and the third housing 13 is connected to the third connector 20. The serpentine tubes 17 are typically composed of multiple sections of round pipe elbows and multiple straight pipes. The sections of round pipe elbows are not on the same plane. The inlet and outlet center lines of the round pipe elbows are parallel but have an eccentricity. Different directions can be achieved by adjusting the number of sections (e.g., 2 or more sections) and parameters (e.g., height, bending radius). The straight pipes connect the multiple sections of round pipe elbows to form the serpentine tube 17 as a whole. Water from the feedwater outlet 5 first flows into the fourth chamber 15, then is branched through multiple serpentine pipes 17 and finally converges in the third chamber 13. The converged water then flows into the boiler from the feedwater inlet 7. The water in each serpentine pipe 17 can exchange heat with the high-temperature flue gas in the first chamber 10, maximizing the recovery of heat from the high-temperature flue gas.

[0031] Based on the above embodiments, in a preferred embodiment, the grid heat storage bricks 14 in the first housing 10 are respectively inserted between adjacent serpentine tubes 17 and fixed to the bottom of the first housing 10; the grid heat storage bricks 14 in the second housing 9 are located below the steel pipe and fixed to the bottom of the second housing 9. Because the high-temperature flue gas can be distributed to every corner of the first housing 10 and the second housing 9, placing the grid heat storage bricks 14 between adjacent serpentine tubes 17 can ensure the absorption of heat from the high-temperature flue gas between adjacent serpentine tubes 17, storing thermal energy to stabilize system temperature fluctuations.

[0032] The above description is merely a specific embodiment of this utility model, enabling those skilled in the art to understand or implement it. Although detailed descriptions have been provided with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments, and all should be covered by the protection scope of the claims.

Claims

1. A boiler blowdown heat recovery device, characterized in that, The system includes a plate heat exchanger (1) and a first housing (10). A second housing (9) is provided on the outer side of the top of the first housing (10). A copper pipe (18) runs through the second housing (9). The two ends of the copper pipe (18) are respectively connected to a first water supply pipe (2) and a second water supply pipe (3). The other end of the second water supply pipe (3) is connected to the cold fluid inlet of the plate heat exchanger (1). The second housing (9) is connected to the first housing (10) through a connecting pipe (11). A one-way valve (12) is installed to allow smoke to flow from the first chamber (10) to the second chamber (9). The top of the second chamber (9) is also connected to a flue pipe (19). A heat recovery component and a fifth chamber (16) are installed inside the first chamber (10). The heat recovery component is provided with a third connector (20) and a fourth connector (21) that penetrate the side wall of the first chamber (10). The outer end of the third connector (20) is connected to a water supply pipe inlet (7), and the other end of the water supply pipe inlet (7) is connected to the boiler inlet. The water inlets are connected, and the outer end of the fourth connector (21) is connected to the water supply pipe outlet (5). The other end of the water supply pipe outlet (5) is connected to the cold fluid outlet of the plate heat exchanger (1). The fifth box (16) is connected to the first box (10) through multiple flue holes (22) evenly distributed on its side wall. The fifth box (16) is connected to the fifth connector (23) that penetrates the side wall of the first box (10). The outer end of the fifth connector (23) is connected to the flue pipe (8). The flue pipe (8) is connected to the... The flue gas outlet of the boiler is connected; multiple grid heat storage bricks (14) are provided in both the first box (10) and the second box (9); the heat recovery component absorbs the heat in the flue gas and heats the water inside it; the hot fluid inlet of the plate heat exchanger (1) is fixedly connected to the first drain pipe (4), the hot fluid outlet of the plate heat exchanger (1) is connected to the second drain pipe (6), the first drain pipe (4) is connected to the boiler's heat exhaust sewage pipe, and the second drain pipe (6) is used to discharge the sewage after heat exchange.

2. The boiler blowdown heat recovery device according to claim 1, characterized in that, The heat recovery component includes a third housing (13), multiple serpentine tubes (17) and a fourth housing (15). The third housing (13) and the fourth housing (15) are respectively fixed to the bottom and top of the inner side of the first housing (10). The multiple serpentine tubes (17) are respectively connected between the third housing (13) and the fourth housing (15) to connect the third housing (13) and the fourth housing (15). The fourth housing (15) is connected to the fourth connector (21), and the third housing (13) is connected to the third connector (20).

3. The boiler blowdown heat recovery device according to claim 2, characterized in that, The grid heat storage bricks (14) in the first box (10) are inserted between the adjacent serpentine pipes (17) and the grid heat storage bricks (14) are fixed to the bottom of the first box (10); the grid heat storage bricks (14) in the second box (9) are located below the steel pipe and the grid heat storage bricks (14) are fixed to the bottom of the second box (9).

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