A heat exchanger for aquaculture and heat exchange method thereof

Abstract

The invention discloses a heat exchanger for aquaculture and a heat exchange method thereof, belonging to the technical field of heat exchangers. The heat exchanger comprises a shell provided with a working chamber and a heat exchange tube bundle, the shell is provided with a first inlet pipe and a first outlet pipe, the first outlet pipe is connected to a working pump and a working motor, the shell is provided with a second inlet pipe and a second outlet pipe, the shell is further provided with a third inlet pipe, and the flow path length between the third inlet pipe and the first outlet pipe is greater than the flow path length between the first inlet pipe and the first outlet pipe. The invention has a fast heat exchange speed; the heat exchanger can perform slow heat exchange, medium speed heat exchange or fast heat exchange, and adapt to the breeding needs of different aquaculture; the working pump can circulate the breeding water in the working chamber of the shell and can also add oxygen to the breeding water; the existing shell-and-tube heat exchanger can be directly modified by adding an inlet pipe, and the structure is simple and the cost is low; it is convenient to clean the outer wall of the heat exchange tube bundle and the inner wall of the shell, and ensure the heat exchange effect after long-term use.

Description

Technical Field

[0001] The invention belongs to the technical field of heat exchangers, and in particular relates to a heat exchanger for aquaculture and a heat exchange method thereof. Background Art

[0002] Water temperature is very important in aquaculture. Common heating methods include boiler heating, electric heating tube heating and heat pump system. Boiler heating and electric heating tube can only heat but not cool down, while heat pump system can heat or cool down water, and has low energy consumption and little pollution, so heat pump system is used more and more. In the application of heat pump system, it is not to heat or cool down the aquaculture water directly, but through the heat exchange medium (usually water) that has been heated or cooled by air source heat pump or water source heat pump. By setting a heat exchanger in the pool, the heat exchange medium slowly heats up or cools the aquaculture water through the heat exchanger. Heat exchangers usually use serpentine pipes, loop pipes and other pipelines. This kind of heat exchanger still has some problems, such as slow heat exchange, which can only rely on the flow of aquaculture water to slowly exchange heat with the water body. If the temperature of the heat exchange medium is blindly increased, it is easy to cause temperature imbalance. The water temperature in some areas of the aquaculture area has reached the requirements, while the water temperature in some areas does not meet the requirements; and the heat exchange speed cannot be mastered, and heat exchange can only be carried out at a constant speed. Summary of the invention

[0003] In view of the above problems existing in the prior art, the technical problem to be solved by the present invention is to provide a heat exchanger for aquaculture and a heat exchange method thereof to ensure the heat exchange effect between the heat exchange medium and the aquaculture water.

[0004] Technical solution: In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0005] A heat exchanger for aquaculture comprises a shell provided with a working chamber and a heat exchange tube bundle arranged in the working chamber and used for circulating a heat exchange medium, the shell being provided with a first inlet pipe and a first outlet pipe communicating with the working chamber, the first outlet pipe being connected to a working pump and a working motor connected to the working pump, the shell being provided with a second inlet pipe and a second outlet pipe communicating with the heat exchange tube bundle, the shell being further provided with a third inlet pipe communicating with the working chamber, the flow path length between the third inlet pipe and the first outlet pipe being greater than the flow path length between the first inlet pipe and the first outlet pipe.

[0006] Preferably, the first inlet pipe is connected to a first inlet valve, and the third inlet pipe is connected to a second inlet valve.

[0007] Preferably, the first outlet pipe is connected to the top wall of the shell, the first inlet pipe and the third inlet pipe are connected to the bottom wall of the shell, the shell includes a first head and a second head arranged at both ends of the shell, and the heat exchange tube bundle includes a plurality of straight tubes.

[0008] Preferably, the second inlet pipe and the second outlet pipe are arranged on the first end cover, and a first partition plate is provided in the middle of the first end cover.

[0009] Preferably, the heat exchange tube bundle includes a plurality of U-shaped tubes and a manifold, one end of the U-shaped tube is connected to the second inlet tube, and the other end of the U-shaped tube is connected to the second outlet tube.

[0010] Preferably, the first inlet pipe is connected to one end of the shell, the third inlet pipe is connected to the other end of the shell, and the first outlet pipe is connected to the top wall of the shell.

[0011] Preferably, the second inlet pipe and the second outlet pipe are both connected to the top wall of the shell, and when the shell is located below the water surface, the pipe openings of the second inlet pipe and the second outlet pipe are located above the water surface.

[0012] Preferably, the shell includes a first sealing plate and a second sealing plate arranged at two ends of the shell.

[0013] Preferably, the working pump outlet is connected to a mixing tube, the mixing tube is connected to an air tube and a diffusion tube, and the air tube is provided with an air inlet located in the air.

[0014] The present invention also provides a heat exchange method for an aquaculture heat exchanger, using the above-mentioned aquaculture heat exchanger, including first speed heat exchange, second speed heat exchange and third speed heat exchange;

[0015] When exchanging heat at the first speed, the first inlet pipe is opened, the third inlet pipe is closed, the aquaculture water enters the shell from the first inlet pipe, exchanges heat with the heat exchange medium in the heat exchange tube bundle, and then is discharged from the first outlet pipe;

[0016] When the heat is exchanged at the second speed, the first inlet pipe and the third inlet pipe are both opened, and the aquaculture water enters the shell from the first inlet pipe and the third inlet pipe, exchanges heat with the heat exchange medium in the heat exchange tube bundle, and then is discharged from the first outlet pipe;

[0017] During the third speed heat exchange, the first inlet pipe is closed, the third inlet pipe is opened, the aquaculture water enters the shell from the third inlet pipe, exchanges heat with the heat exchange medium in the heat exchange tube bundle, and then is discharged from the first outlet pipe.

[0018] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0019] 1. Two inlet pipes with different flow paths to the outlet pipe are set, and a working pump is set on the outlet pipe to allow the aquaculture water to continuously enter the shell from the inlet pipe for heat exchange, with a fast heat exchange speed;

[0020] 2. The flow paths of the two inlet pipes and the outlet pipes are different, so the heat exchange time of the incoming aquaculture water is different. The heat exchanger can perform slow heat exchange, medium heat exchange or fast heat exchange, and can be used when raising different types of aquatic products. While ensuring the heat exchange speed, it reduces the temperature difference between the aquaculture water after heat exchange and the original aquaculture water, reduces the death of aquaculture fish and shrimp, improves aquaculture efficiency, and adapts to the aquaculture needs of different aquatic products;

[0021] 3. The first outlet pipe is connected with a working pump and a working motor, and the outlet of the working pump is connected with a mixing pipe, an air pipe and a diffusion pipe. The working pump can circulate the aquaculture water in the working chamber of the shell and also oxygenate the aquaculture water, thereby meeting the aquaculture needs and saving energy and reducing consumption;

[0022] 4. When the shell adopts a head and tube sheet structure and the heat exchange tube bundle adopts multiple straight tubes, the existing shell-and-tube heat exchanger can be directly modified by adding inlet tubes, which has a simple structure and low cost;

[0023] 5. When the shell adopts two sealing plates and the heat exchange tube bundle adopts multiple U-shaped tubes, it is convenient to clean the outer wall of the heat exchange tube bundle and the inner wall of the shell to ensure the heat exchange effect after long-term use. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of the structure of a heat exchanger according to embodiment 1 of the present invention;

[0025] Figure 2 is a schematic diagram of the shell structure of Example 1;

[0026] Figure 3 It is a schematic diagram of the structure of the oxygenation part of Example 1;

[0027] Figure 4 It is a schematic diagram of the structure of the heat exchanger of Example 2 of the present invention. DETAILED DESCRIPTION

[0028] The present invention is further illustrated below in conjunction with specific examples. The examples are implemented based on the technical solutions of the present invention. It should be understood that these examples are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0029] Example 1

[0030] like Figure 1As shown, a heat exchanger for aquaculture includes a shell 1 and a heat exchange tube bundle 2. The shell 1 is cylindrical as a whole. The shell 1 includes a main body 19, a first tube sheet 13, a second tube sheet 14, a first head 11 and a second head 12. The main body 19 is cylindrical. The first tube sheet 13 and the second tube sheet 14 are respectively connected to both ends of the main body 19. The first head 11 is detachably connected to one end of the main body 19, and the second head 12 is detachably connected to the other end of the main body 19. A working chamber is provided in the shell 1. The heat exchange tube bundle 2 includes a plurality of straight tubes 201. The plurality of straight tubes 201 are arranged in the working chamber and one end of the plurality of straight tubes 201 is connected to the first head 11, and the other end of the plurality of straight tubes 201 is connected to the second head 12. A first partition plate 111 is provided in the middle of the first head 11. The first partition plate 111 The plate 111 divides the area inside the first head 11 into a liquid inlet area and a liquid outlet area, which are respectively connected to a plurality of straight tubes 201. A second inlet pipe 21 and a second outlet pipe 22 are provided on the shell 1. The second inlet pipe 21 is connected to the liquid inlet area, and the second outlet pipe 22 is connected to the liquid outlet area. The second inlet pipe 21 and the second outlet pipe 22 are used to connect to the evaporator or condenser of the external heat pump system (the evaporator or condenser cools down or heats up the heat exchange medium), so as to introduce the heat exchange medium into the heat exchange tube bundle 2. The heat exchange medium enters the liquid inlet area of ​​the first head 11 from the second inlet pipe 21 and then enters the straight tube 201, reaches the area inside the second head 12 at the other end, enters the liquid outlet area of ​​the first head 11 through the plurality of straight tubes 201 in the lower part, and is finally discharged from the second outlet pipe 22. A first inlet pipe 31, a first outlet pipe 32 and a third inlet pipe 33 are provided on the main body 19 of the shell 1. The first inlet pipe 31 and the third inlet pipe 33 are connected to the bottom wall of the main body 19 and communicated with the working chamber. A bracket 18 is connected to the outer bottom wall of the main body 19. When the shell 1 is immersed in the aquaculture water, the bracket 18 makes the two inlet pipes have a certain distance from the bottom of the aquaculture pond to ensure that the two inlet pipes can normally inlet water. The first outlet pipe 32 is connected to the top wall of the shell 1 and communicates with the working chamber. Water in the aquaculture area enters the working chamber of the shell 1 from the first inlet pipe 31 and the third inlet pipe 33 and is discharged from the first outlet pipe 32 after heat exchange with the heat exchange medium at the pipe wall of the straight pipe 201. A working pump 41 is connected to the first outlet pipe 32. A working motor 42 is connected to the working pump 41. The working motor 42 adopts an existing waterproof motor. When working, the water in the working chamber of the shell 1 is continuously pumped out by driving the working pump 41 to rotate, so that the aquaculture water continuously enters the shell 1 for heat exchange, and the aquaculture water is heated or cooled as a whole.

[0031] like Figure 1 and Figure 3As shown, the outlet of the working pump 41 is connected to a mixing pipe 43, the mixing pipe 43 is connected to an air pipe 44 and a diffusion pipe 45, and the air pipe 44 is provided with an air inlet 441 located in the air. The working pump 41, the working motor 42, the mixing tube 43, the air tube 44 and the diffusion tube 45 form an oxygenation part. When in use, the shell 1 of the heat exchanger, the working pump 41 and the working motor 42 are all immersed in the aquaculture water, the air inlet 441 is located in the air, the working pump 41 continuously extracts the water that has been heat exchanged in the working chamber of the shell 1, the nozzle of the working pump 41 outlet is located in the mixing tube 43, the water flow ejected from the nozzle of the working pump 41 is a high-speed jet, and the air around the jet is drawn into the jet and taken away, so that a vacuum is generated in the mixing tube 43. Under the action of atmospheric pressure, air continuously enters the mixing tube 43 from the air inlet 441 and the air tube 44, the jet collides with the air, and the oxygen is effectively dissolved in the water. The gas-liquid two-phase mixed flow in the mixing tube 43 is ejected through the diffusion tube 45, and the oxygen dissolved in the water is released into the surrounding aquaculture water, thereby increasing the oxygen content of the aquaculture water. There is no need to set up an aerator separately in the aquaculture area, which saves energy and reduces consumption.

[0032] like Figure 1 and Figure 2 As shown, the first inlet pipe 31 is arranged at the right end of the bottom wall of the main body 19, the third inlet pipe 33 is arranged at the left end of the bottom wall of the main body 19, the first outlet pipe 32 is arranged on the top wall of the main body 19, and the distance from the first outlet pipe 32 to the right end of the main body 19 is smaller than the distance from the first outlet pipe 32 to the left end of the main body 19. The flow path length between the third inlet pipe 33 and the first outlet pipe 32 is greater than the flow path length between the first inlet pipe 31 and the first outlet pipe 32. The flow path length is the path through which the aquaculture water flows from the inlet pipe to the outlet pipe. Therefore, the aquaculture water entering from the third inlet pipe 33 and the aquaculture water entering from the first inlet pipe 31 have different heat exchange paths with the heat exchange tube bundle 2 and thus have different temperatures after heat exchange. For example, when the aquaculture water needs to be heated, the aquaculture water entering from the third inlet pipe 33 has a high temperature due to the long heat exchange path, and the aquaculture water entering from the first inlet pipe 31 has a low temperature due to the short heat exchange path. A plurality of baffles 81 are provided in the shell 1, some of the baffles 81 are connected to the inner top wall of the main body 19, and another portion of the baffles 81 are connected to the inner bottom wall of the main body 19. The baffles 81 lengthen the flow path between the first inlet pipe 31 and the first outlet pipe 32 and the flow path between the third inlet pipe 33 and the first outlet pipe 32, thereby extending the heat exchange time between the aquaculture water and the heat exchange medium and improving the heat exchange effect. The first inlet pipe 31 is connected to the first inlet valve 51, and the third inlet pipe 33 is connected to the second inlet valve 52. The first inlet valve 51 and the second inlet valve 52 both use existing waterproof electric butterfly valves to control the opening and closing of the first inlet pipe 31 and the third inlet pipe 33, so as to control which inlet pipe the aquaculture water enters the working chamber of the shell 1.

[0033] This embodiment also provides a heat exchange method for an aquaculture heat exchanger, using the above-mentioned aquaculture heat exchanger, including first speed heat exchange, second speed heat exchange and third speed heat exchange.

[0034] During the first speed heat exchange, the first inlet valve 51 is opened to control the first inlet pipe 31 to be opened, and the second inlet valve 52 is closed to control the third inlet pipe 33 to be closed. The aquaculture water enters the shell 1 from the first inlet pipe 31 and exchanges heat with the heat exchange medium in the heat exchange tube bundle 2, and is discharged from the first outlet pipe 32. After the first inlet pipe 31 enters the shell, the heat exchange path between the aquaculture water and the heat exchange medium is short and the heat exchange time is short, and the temperature change of the aquaculture water is small. Therefore, the temperature difference between the aquaculture water discharged from the first outlet pipe 32 and the overall aquaculture water after heat exchange is small, and the heat exchange speed is slow.

[0035] During the second speed heat exchange, the first inlet valve 51 and the second inlet valve 52 are both opened to control the first inlet pipe 31 and the third inlet pipe 33 to be opened, and the aquaculture water enters the shell 1 from the first inlet pipe 31 and the third inlet pipe 33 and is discharged from the first outlet pipe 32 after heat exchange with the heat exchange medium in the heat exchange tube bundle 2. The aquaculture water entering the first inlet pipe 31 and the aquaculture water entering the third inlet pipe 33 are mixed after heat exchange and are discharged from the first outlet pipe 32. The temperature of the aquaculture water after heat exchange is higher than that of the aquaculture water discharged during the first speed heat exchange, and the heat exchange speed is medium.

[0036] During the third speed heat exchange, the first inlet valve 51 is closed to control the first inlet pipe 31 to be closed, and the second inlet valve 52 is opened to control the third inlet pipe 33 to be opened. The aquaculture water enters the shell 1 from the third inlet pipe 33 and exchanges heat with the heat exchange medium in the heat exchange tube bundle 2, and then is discharged from the first outlet pipe 32. After the third inlet pipe 33 enters the shell, the heat exchange path between the aquaculture water and the heat exchange medium is long and the heat exchange time is long, the temperature of the aquaculture water changes greatly, and the temperature of the aquaculture water after heat exchange is higher than the aquaculture water discharged during the second speed heat exchange, and the heat exchange speed is fast.

[0037] The first speed heat exchange, the second speed heat exchange and the third speed heat exchange correspond to slow heat exchange, medium speed heat exchange and fast heat exchange respectively, and can be used in breeding different types of aquatic products such as fish or shrimp. While ensuring the heat exchange speed, the temperature difference of the heat exchange breeding water is reduced to reduce the death of farmed fish and shrimp, improve the breeding efficiency, and adapt to the breeding needs of different aquatic products.

[0038] Example 2

[0039] The difference from Example 1 is that the shell 1 of this embodiment includes a main body 19, a first sealing plate 15 and a second sealing plate 16, the first sealing plate 15 and the second sealing plate 16 are detachably connected to the two ends of the main body 19, the first sealing plate 15 is at the right end, and the second sealing plate 16 is at the left end, the first inlet pipe 31 is connected to the first sealing plate 15, the third inlet pipe 33 is connected to the second sealing plate 16, the first outlet pipe 32 is connected to the top wall of the shell 1, and the distance from the first outlet pipe 32 to the right end of the shell 1 is smaller than the distance from the first outlet pipe 32 to the left end of the shell 1, so that the flow path length between the first inlet pipe 31 and the first outlet pipe 32 is smaller than the flow path length between the third inlet pipe 33 and the first outlet pipe 32. The first inlet pipe 31 and the third inlet pipe 33 are arranged at the two ends of the shell 1, and the aquaculture water enters the working chamber of the shell 1 from the two ends. There is no need to set a bracket at the bottom of the shell 1. The bottom of the main body 19 is flat and can be directly placed at the bottom of the pool body. The difference from Example 1 is that the heat exchange tube bundle 2 includes a plurality of U-shaped tubes 202 and a collector plate 203. The collector plate 203 is arranged at one end of the working chamber in the shell 1. A partition plate is arranged in the middle of the collector plate 203 to divide the area in the collector plate 203 into an inlet area and an outlet area. The pipe openings at one end of the plurality of U-shaped tubes 202 are connected to the inlet area of ​​the collector plate 203, and the pipe openings at the other end of the plurality of U-shaped tubes 202 are connected to the outlet area of ​​the collector plate 203. The U-shaped end of the U-shaped tube 202 extends to the other end of the working chamber. The second inlet pipe 21 is connected to the inlet area of ​​the collector plate 203, so that the U-shaped tube 202 One end of the U-shaped tube 202 is connected to the second inlet pipe 21, and the second outlet pipe 22 is connected to the outlet area of ​​the confluence plate 203, so that the other end of the U-shaped tube 202 is connected to the second outlet pipe 22, and the heat exchange medium enters the U-shaped tube 202 from the second inlet pipe 21, exchanges heat with the aquaculture water in the working chamber of the shell 1, and is discharged from the second outlet pipe 22. In this embodiment, the tube walls of the second inlet pipe 21 and the second outlet pipe 22 are both connected to the top wall of the shell 1. When the shell 1 is located below the water surface, the tube openings of the second inlet pipe 21 and the second outlet pipe 22 are located above the water surface, which is convenient for connecting with external pipelines when the heat exchanger is installed. When the heat exchanger is used in the aquaculture pond, the heat exchange medium passes through the tube side, and the heat exchange medium in the external heat pump system does not contact the outside, so there are few impurities and the tube side of the heat exchanger will not be blocked. However, the aquaculture water passes through the shell side of the heat exchanger, and there are many impurities in the shell side. After long-term use, the impurities are easily attached to the outer wall of the heat exchange tube bundle 2 and the inner wall of the shell 1. In this embodiment, the first sealing plate 15 and the second sealing plate 16 are detachable, which is convenient for cleaning the outer wall of the heat exchange tube bundle 2 and the inner wall of the shell 1 to ensure the heat exchange effect.

[0040] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A heat exchanger for aquaculture, characterized in that: The invention comprises a shell (1) provided with a working chamber and a heat exchange tube bundle (2) arranged in the working chamber and used for circulating a heat exchange medium. The shell (1) is provided with a first inlet pipe (31) and a first outlet pipe (32) connected to the working chamber. The first outlet pipe (32) is connected to a working pump (41) and a working motor (42) connected to the working pump (41). The shell (1) is provided with a second inlet pipe (21) and a second outlet pipe (22) connected to the heat exchange tube bundle (2). The shell (1) is also provided with a third inlet pipe (33) connected to the working chamber. The flow path length between the third inlet pipe (33) and the first outlet pipe (32) is greater than the flow path length between the first inlet pipe (31) and the first outlet pipe (32).

2. The heat exchanger for aquaculture according to claim 1, characterized in that: The first inlet pipe (31) is connected to a first inlet valve (51), and the third inlet pipe (33) is connected to a second inlet valve (52).

3. The heat exchanger for aquaculture according to claim 2, characterized in that: The first outlet pipe (32) is connected to the top wall of the shell (1), the first inlet pipe (31) and the third inlet pipe (33) are connected to the bottom wall of the shell (1), the shell (1) comprises a first head (11) and a second head (12) arranged at both ends of the shell (1), and the heat exchange tube bundle (2) comprises a plurality of straight tubes (201).

4. The heat exchanger for aquaculture according to claim 3, characterized in that: The second inlet pipe (21) and the second outlet pipe (22) are arranged on the first end cap (11), and a first partition plate (111) is arranged in the middle of the first end cap (11).

5. The heat exchanger for aquaculture according to claim 2, characterized in that: The heat exchange tube bundle (2) comprises a plurality of U-shaped tubes (202) and a collector plate (203); one end of the U-shaped tube (202) is connected to the second inlet tube (21); and the other end of the U-shaped tube (202) is connected to the second outlet tube (22).

6. The heat exchanger for aquaculture according to claim 5, characterized in that: The first inlet pipe (31) is connected to one end of the shell (1), the third inlet pipe (33) is connected to the other end of the shell (1), and the first outlet pipe (32) is connected to the top wall of the shell (1).

7. The heat exchanger for aquaculture according to claim 5, characterized in that: The second inlet pipe (21) and the second outlet pipe (22) are both connected to the top wall of the shell (1); when the shell (1) is located below the water surface, the pipe openings of the second inlet pipe (21) and the second outlet pipe (22) are located above the water surface.

8. The heat exchanger for aquaculture according to claim 6, characterized in that: The housing (1) comprises a first sealing plate (15) and a second sealing plate (16) which are arranged at two ends of the housing (1).

9. The heat exchanger for aquaculture according to claim 1, characterized in that: The outlet of the working pump (41) is connected to a mixing pipe (43), the mixing pipe (43) is connected to an air pipe (44) and a diffusion pipe (45), and the air pipe (44) is provided with an air inlet (441) located in the air.

10. A heat exchange method for a heat exchanger for aquaculture, using the heat exchanger for aquaculture as claimed in any one of claims 1 to 9, comprising a first speed heat exchange, a second speed heat exchange and a third speed heat exchange; When heat is exchanged at the first speed, the first inlet pipe (31) is opened, the third inlet pipe (33) is closed, and the aquaculture water enters the shell (1) from the first inlet pipe (31), exchanges heat with the heat exchange medium in the heat exchange tube bundle (2), and is then discharged from the first outlet pipe (32); When heat is exchanged at the second speed, the first inlet pipe (31) and the third inlet pipe (33) are both opened, and the aquaculture water enters the shell (1) from the first inlet pipe (31) and the third inlet pipe (33), exchanges heat with the heat exchange medium in the heat exchange tube bundle (2), and is then discharged from the first outlet pipe (32); During the third speed heat exchange, the first inlet pipe (31) is closed, the third inlet pipe (33) is opened, the aquaculture water enters the shell (1) from the third inlet pipe (33), exchanges heat with the heat exchange medium in the heat exchange tube bundle (2), and is then discharged from the first outlet pipe (32).

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