Shell-and-tube heat exchanger and mariculture heat pump unit

Abstract

The utility model belongs to the field of heat exchangers, and discloses a shell-and-tube heat exchanger and a mariculture heat pump unit adopting the shell-and-tube heat exchanger, the shell-and-tube heat exchanger comprises a tube box, a tube plate, a heat exchange tube bundle and a heat exchanger cylinder, and the heat exchanger cylinder comprises a heat exchanger cylinder A and a heat exchanger cylinder B which are connected through a cylinder flange and a threaded fastener; the mariculture heat pump unit comprises a compressor, a condenser, an expansion valve and a shell-and-tube heat exchanger which are connected through a refrigerant pipeline. A bottom support of a heat exchanger cylinder is fixedly connected with a unit frame through a threaded fastener. When the heat exchange tube bundle needs to be cleaned or overhauled, only one section of the barrel needs to be disassembled and assembled, so that the workload of disassembly and assembly is small, the cleaning operation efficiency is high, the required working space is small during the cleaning operation, and the field operation is convenient.

Description

Technical Field

[0001] This utility model relates to the technical field of heat pump units and their components, specifically to a shell-and-tube heat exchanger and a seawater aquaculture heat pump unit using the shell-and-tube heat exchanger. Background Technology

[0002] A heat exchanger is a device that transfers heat between two or more fluids at different temperatures. Currently, among the many types of heat exchangers, shell-and-tube heat exchangers are the most widely used, with U-tube heat exchangers being the most common type. They consist of main components such as tube boxes, tube sheets, heat exchanger shells, and U-shaped heat exchange tube bundles installed inside the heat exchanger shells.

[0003] In the aquaculture industry, seawater temperatures are relatively low in winter, which slows down the growth of seafood. To meet the temperature requirements for normal growth, the aquaculture industry commonly uses seawater aquaculture heat pump units to effectively raise the temperature of the aquaculture water. The evaporators used in these units are generally shell-and-tube heat exchangers, using either discharged aquaculture wastewater or fresh seawater as the hot water source for the evaporator side. Because the wastewater accumulates feed and waste products needed for seafood growth, and fresh seawater contains silt, impurities in the shell-side heat exchange medium easily form scale that adheres to the heat exchange tube walls as the heat pump unit operates for extended periods. This scale buildup increases the thermal resistance of the heat exchanger, reduces heat exchange efficiency, and severely impacts its performance. Therefore, it is necessary to regularly clean the heat exchanger tube bundles to remove scale and improve heat exchange efficiency. When cleaning the outer walls of heat exchanger tubes or performing maintenance, the heat exchanger needs to be disassembled. The usual procedure is to first completely remove the tube box, tube sheet, and heat exchanger tube bundle from the heat exchanger shell, clean the tube bundle, and then reassemble it. This conventional method has two drawbacks: firstly, the combined weight of the tube box, tube sheet, and heat exchanger tube bundle is significant, resulting in a large workload for disassembly and reassembly; secondly, completely removing the tube box, tube sheet, and heat exchanger tube bundle from the heat exchanger shell requires a considerable amount of space, making this method unsuitable in situations with limited space. Summary of the Invention

[0004] In view of this, the technical problem to be solved by this utility model is to provide a shell-and-tube heat exchanger that requires less disassembly and assembly work during cleaning or maintenance, and requires less workspace.

[0005] Based on the same technical concept, another technical problem to be solved by this utility model is to provide a seawater aquaculture heat pump unit that uses the shell-and-tube heat exchanger.

[0006] To solve the aforementioned technical problems regarding shell-and-tube heat exchangers, the technical solution of this utility model is: a shell-and-tube heat exchanger, horizontally arranged, comprising: a tube box, a tube sheet, and a heat exchanger shell arranged and fixed together coaxially; a heat exchange tube bundle is disposed within the heat exchanger shell; the heat exchanger shell is segmented, including heat exchanger shell A and heat exchanger shell B detachably and fixedly connected together; heat exchanger shell A has a shell flange at both ends; heat exchanger shell B has a shell flange at one end and a closed end at the other; heat exchanger shell A and heat exchanger shell B are fastened together by the shell flange and threaded fasteners; heat exchanger shell A has a water inlet A, and heat exchanger shell B has a water inlet B; a partition plate is disposed within the tube box, dividing the inner cavity of the tube box into a liquid distribution chamber and a gas collection chamber; the tube box is connected to... The refrigerant pipe A is connected to the liquid distribution chamber, and the refrigerant pipe B is connected to the gas collection chamber. The tube sheet is provided with a plurality of tube holes, which are divided into a liquid distribution tube hole area corresponding to the position of the liquid distribution chamber and a gas collection tube hole area corresponding to the position of the gas collection chamber. The area between the liquid distribution tube hole area and the gas collection tube hole area is a non-perforated area of ​​the tube sheet. A plurality of tube sheet connecting through holes are provided around the periphery of the tube sheet. The tube sheet flange at one end of the heat exchanger shell A, the tube sheet connecting through holes, and the tube box are fastened together by threaded fasteners. The heat exchange tube bundle is a U-shaped heat exchange tube bundle, which is supported in the heat exchanger shell by a baffle plate. One open end of the U-shaped heat exchange tube bundle is connected to the tube hole in the gas collection tube hole area and is connected to the gas collection chamber. The other open end of the U-shaped heat exchange tube bundle is connected to the tube hole in the liquid distribution tube hole area and is connected to the liquid distribution chamber.

[0007] The bottom of the heat exchanger shell A is fixed with a bracket A, and the bottom of the heat exchanger shell B is fixed with a bracket B.

[0008] A sealing gasket A is provided between the tube box and the tube sheet; a sealing gasket B is also provided between the tube sheet and the shell flange of the heat exchanger body A, and between the shell flange of the heat exchanger body A and the shell flange of the heat exchanger body B.

[0009] The sealing gasket B includes an annular body with a plurality of concentric and evenly distributed gasket through holes.

[0010] The sealing gasket A includes an annular body with several concentric and evenly distributed gasket through holes. A partition is provided inside the annular body along the diameter direction, and the partition corresponds to the position of the partition plate in the pipe box. The partition divides the interior of the sealing gasket A into a non-communicating liquid-distributing half-hole and a gas-collecting half-hole. The liquid-distributing half-hole is connected to the liquid-distributing chamber, and the gas-collecting half-hole is connected to the gas-collecting chamber.

[0011] The pipe box is a flat pipe box.

[0012] To solve the aforementioned technical problems regarding seawater aquaculture heat pump units, the technical solution of this utility model is: a seawater aquaculture heat pump unit, comprising: a compressor, a condenser, an expansion valve, and an evaporator connected via refrigerant pipelines. The evaporator adopts the aforementioned shell-and-tube heat exchanger. The heat exchanger shell is fixedly connected to the unit frame via a support at its bottom using threaded fasteners. Refrigerant pipe port A is connected to the outlet of the expansion valve, and refrigerant pipe port B is connected to the inlet of the compressor.

[0013] Water inlet A is the inlet connected to aquaculture wastewater, and water inlet B is the outlet.

[0014] Alternatively, water inlet A can be a water inlet connected to fresh seawater, and water inlet B can be a water outlet.

[0015] After adopting the above technical solution, the present invention has achieved the following beneficial technical effects:

[0016] The shell-and-tube heat exchanger of this invention includes a tube box, tube sheet, and heat exchanger shell arranged and fixed together in the same direction. A heat exchange tube bundle is installed inside the heat exchanger shell. The heat exchanger shell is segmented, including heat exchanger shell A and heat exchanger shell B, which are detachably and fixedly connected together. Heat exchanger shell A has a shell flange at both ends, and heat exchanger shell B has a shell flange at one end and a closed end at the other. Heat exchanger shell A and heat exchanger shell B are fastened together by shell flanges and threaded fasteners. Heat exchanger shell A has a water inlet A, and heat exchanger shell B has a water inlet B. The seawater aquaculture heat pump unit of this invention includes a compressor, condenser, expansion valve, and evaporator connected by refrigerant piping. The evaporator uses the aforementioned shell-and-tube heat exchanger. The support at the bottom of the heat exchanger shell is connected to the unit frame via... Threaded fasteners are used for fixing connections. After a long period of operation, the shell-side medium of the shell-and-tube heat exchanger contains impurities and easily forms scale on the tube walls. When cleaning or maintenance is required, remove the threaded fasteners connecting the shell flanges of heat exchanger body A and heat exchanger body B, remove the threaded fasteners connecting the water inlet B of heat exchanger body B, and remove the threaded fasteners between the bottom of heat exchanger body B and the unit frame of the heat pump. Then, heat exchanger body B can be pulled out, and most of the heat exchanger tube bundle will be exposed above the unit frame along its length. Then, cleaning equipment (such as a high-pressure water gun) can be used to thoroughly clean the heat exchanger tube bundle, heat exchanger body A, and heat exchanger body B to remove the deposited scale and improve heat exchange efficiency. After cleaning, the heat exchanger parts are reconnected using the threaded fasteners and put back into use. The heat exchanger shell of this invention adopts a segmented design. When cleaning or repairing the heat exchanger, only one segment of the shell needs to be disassembled and reassembled. On the one hand, fewer parts need to be disassembled and reassembled, the weight is lighter, and the workload of disassembly and assembly is reduced, which can effectively improve the efficiency of cleaning operations. On the other hand, the segmented design of the heat exchanger shell greatly reduces the length of the shell that needs to be disassembled and reassembled compared with the one-piece design of the heat exchanger shell in the prior art. The working space required for cleaning operations is reduced, which effectively reduces the space required for equipment site (especially in the length direction). It is basically not restricted by the small space of the application site, which facilitates on-site operation and is flexible and convenient. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the shell-and-tube heat exchanger structure according to an embodiment of the present invention;

[0018] Figure 2 yes Figure 1 A top-down view;

[0019] Figure 3 yes Figure 1 A schematic diagram showing the tube box, tube sheet, and heat exchange tube bundle fixed together.

[0020] Figure 4 yes Figure 3 Enlarged diagram of part A in the diagram;

[0021] Figure 5 yes Figure 2 Schematic diagram of heat exchanger shell B being removed and extracted by the lieutenant general;

[0022] Figure 6 This is a schematic diagram of the tube sheet structure in an embodiment of this utility model;

[0023] Figure 7 This is a schematic diagram of the sealing gasket A structure in an embodiment of this utility model;

[0024] Figure 8 This is a schematic diagram of the sealing gasket B structure in an embodiment of this utility model;

[0025] In the diagram: 1. Tube box; 2. Tube sheet; 21. Tube sheet non-perforated area; 22. Gas collecting tube perforated area; 23. Liquid separating tube perforated area; 24. Tube sheet connection through hole; 3. Heat exchanger shell A; 31. Shell flange; 4. Heat exchanger shell B; 51. Support A; 52. Support B; 61. Refrigerant inlet A; 62. Refrigerant inlet B; 7. Divider plate; 8. Sealing gasket A; 81. Divider section; 82. Gas collecting half-hole; 83. Liquid separating half-hole; 84. Gasket through hole; 9. Sealing gasket B; 10. Water inlet A; 12. Water inlet B; 13. Baffle plate; 14. U-shaped heat exchanger tube bundle; S1. Gas collecting chamber; S2. Liquid separating chamber. Detailed Implementation

[0026] It should be noted that, in this description, unless otherwise specified or limited, the terms “connected,” “linked,” “interconnected,” etc., should be interpreted broadly, and can refer to a direct connection between two components or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0027] The embodiments of this utility model will now be described in further detail and without limitation, with reference to the accompanying drawings.

[0028] Example 1

[0029] like Figure 1 and Figure 3 As shown, the shell-and-tube heat exchanger of this utility model embodiment is horizontally arranged and includes a tube box 1, a tube sheet 2 and a heat exchanger shell arranged and fixed together in the same direction. A heat exchange tube bundle is provided in the heat exchanger shell, wherein the heat exchange tube bundle is a U-shaped heat exchange tube bundle 14, which is supported in the heat exchanger shell by a baffle 13.

[0030] like Figure 1 , Figure 2 and Figure 5As shown, the heat exchanger shell is segmented, including heat exchanger shell A3 and heat exchanger shell B4, which are detachably and fixedly connected together. Shell flanges 31 are provided at both ends of heat exchanger shell A3, and a shell flange is provided at one end of heat exchanger shell B4, with the other end being a closed end. Heat exchanger shell A3 and heat exchanger shell B4 are fastened together by shell flanges and threaded fasteners. A water inlet A10 is provided on heat exchanger shell A3, and a water inlet B12 is provided on heat exchanger shell B4. The optimized design places water inlet B12 near the closed end to ensure a longer flow path for the shell-side fluid, resulting in sufficient heat exchange and improved heat exchange efficiency. A support A51 is fixed to the bottom of heat exchanger shell A3, and a support B52 is fixed to the bottom of heat exchanger shell B4.

[0031] like Figure 4 As shown, a partition plate 7 is provided inside the pipe box 1, dividing the inner cavity of the pipe box into a liquid distribution chamber S2 and a gas collection chamber S1. The pipe box 1 is connected to a refrigerant pipe port B62 that communicates with the liquid distribution chamber S2 and a refrigerant pipe port A61 that communicates with the gas collection chamber S1. In this embodiment, the pipe box 1 is optimized to be a flat pipe box, which has a better liquid distribution / gas collection effect than the end-shaped pipe box of the prior art.

[0032] like Figure 6 As shown, the tube sheet 2 is provided with a plurality of tube holes, which are divided into a liquid distribution tube hole region 23 corresponding to the position of the liquid distribution chamber S2 and a gas collection tube hole region 22 corresponding to the position of the gas collection chamber S1. The area between the liquid distribution tube hole region 23 and the gas collection tube hole region 22 is a tube sheet non-perforated region 21. A plurality of tube sheet connecting through holes 24 are provided around the periphery of the tube sheet. Figure 1 and Figure 5 As shown, the shell flange 31 at one end of the heat exchanger shell A3, the tube sheet connection through hole 24, and the tube box 1 are fastened together by threaded fasteners. Figure 4 As shown, one open end of the U-shaped heat exchange tube bundle 14 is connected to the tube hole in the gas collecting tube hole region 22 and communicates with the gas collecting chamber S1, and the other open end of the U-shaped heat exchange tube bundle 14 is connected to the tube hole in the liquid separating tube hole region 23 and communicates with the liquid separating chamber S2.

[0033] like Figure 2 As shown, to ensure that the shell-and-tube heat exchanger forms a closed pressure vessel, a sealing gasket A8 is provided between the tube box 1 and the tube sheet 2; a sealing gasket B9 is provided between the tube sheet 2 and the shell flange 31 of the heat exchanger shell A3, and between the shell flange of the heat exchanger shell A3 and the shell flange of the heat exchanger shell B4.

[0034] like Figure 7As shown, the sealing gasket A8 includes an annular body with several concentric and evenly distributed gasket through holes 84. A partition 81 is provided inside the annular body along the diameter direction. The partition 81 corresponds to the partition plate 7 inside the pipe box 1. The partition 81 divides the interior of the sealing gasket A8 into a non-communicating liquid distribution half hole 83 and a gas collection half hole 82. The liquid distribution half hole 83 is connected to the liquid distribution chamber S2 of the pipe box 1, and the gas collection half hole 82 is connected to the gas collection chamber S1 of the pipe box 1.

[0035] like Figure 8 As shown, the sealing gasket B9 includes an annular body with several concentric and evenly distributed gasket through holes to facilitate the insertion of threaded fasteners.

[0036] like Figure 5 As shown, when the scale buildup on the heat exchanger tube walls severely affects the heat exchanger efficiency, the threaded fasteners connecting heat exchanger shell A3 and heat exchanger shell B4, the threaded fasteners connecting the water inlet B12 of heat exchanger shell B4, and the threaded fasteners of the support B52 at the bottom of heat exchanger shell B4 can be removed. This allows heat exchanger shell B4 to be pulled out, exposing most of the U-shaped heat exchanger tube bundle 14 along its length. Then, cleaning equipment (such as a high-pressure water gun) can be used to thoroughly clean the U-shaped heat exchanger tube bundle 14, heat exchanger shell A3, and heat exchanger shell B4 to remove the deposited scale and improve heat exchange efficiency. After cleaning, the heat exchanger can be reconnected using the threaded fasteners and put back into use. The heat exchanger shell of this invention adopts a segmented design. When cleaning / maintaining the heat exchanger, only the B4 segment of the heat exchanger shell needs to be disassembled. On the one hand, fewer parts need to be disassembled, the weight is lighter, and the workload of disassembly and assembly is reduced, which can effectively improve the efficiency of cleaning operations. On the other hand, the segmented design of the heat exchanger shell greatly reduces the length of the shell that needs to be disassembled compared with the one-piece design of the heat exchanger shell in the prior art. The working space required for cleaning operations is small, which effectively reduces the space required for equipment site (especially in the length direction). It is basically not restricted by the limited space of the application site, which facilitates on-site operations.

[0037] Example 2

[0038] This utility model provides a seawater aquaculture heat pump unit, including a compressor, condenser, expansion valve, evaporator, and other necessary heat pump unit components known to those skilled in the art, all connected via refrigerant pipelines. The evaporator employs the shell-and-tube heat exchanger described above. The heat exchanger shell is fixedly connected to the heat pump unit frame via support A51 and support B52 at its bottom using threaded fasteners. Refrigerant pipe port A61 is connected to the outlet of the expansion valve, and refrigerant pipe port B62 is connected to the inlet of the compressor. Water inlet A10 is the inlet, connected to aquaculture wastewater; water inlet B12 is the outlet.

[0039] When the seawater aquaculture heat pump unit is running, the refrigerant, after being throttled and depressurized by the expansion valve, enters the liquid distribution chamber S2 through the refrigerant pipe port A61. The refrigerant is evenly distributed into the U-shaped heat exchange tube bundle 14. The discharged aquaculture wastewater enters the heat exchanger shell through the water inlet A10. In the shell side, it is repeatedly reversed by the baffle plate 13 to increase turbulence and improve the efficiency of the heat exchanger. After fully exchanging heat with the refrigerant in the U-shaped heat exchange tube bundle 14, it is discharged through the water inlet B12. The refrigerant in the U-shaped heat exchange tube bundle 14 absorbs heat and returns to the gas collection chamber S1 through the U-shaped heat exchange tube bundle 14. It completes the refrigeration cycle through the refrigerant pipe port B62, the compressor, and the refrigerant pipeline. Fresh seawater is heated in the condenser to meet the temperature requirements and replenish the aquaculture area with fresh seawater.

[0040] Because aquaculture wastewater accumulates feed and wastewater needed for seafood growth, scale builds up on the walls of the U-shaped heat exchanger tube bundle 14 after prolonged operation of the heat pump unit, affecting heat exchanger efficiency. When cleaning or maintenance is required, as described in Example 1, remove the threaded fasteners connecting heat exchanger shell A3 and heat exchanger shell B4, remove the threaded fasteners connecting the water inlet B12 of heat exchanger shell B4, and remove the threaded fasteners connecting the support B52 at the bottom of heat exchanger shell B4 to the heat pump unit frame. This allows heat exchanger shell B4 to be extracted, exposing most of the U-shaped heat exchanger tube bundle 14 along its length above the heat pump unit frame. Then, cleaning equipment (such as a high-pressure water gun) can be used to thoroughly clean the U-shaped heat exchanger tube bundle 14, heat exchanger shell A3, and heat exchanger shell B4 to remove the accumulated scale and improve heat exchange efficiency. After cleaning, reconnect all parts of the heat exchanger using the threaded fasteners and put it back into use.

[0041] Example 3

[0042] The seawater aquaculture heat pump unit provided in Embodiment 3 of this utility model has the same structure and principle as Embodiment 2. The difference is that the water inlet A10 is the water inlet, which is connected to fresh seawater and uses fresh seawater as the heat source water on the heating evaporator side of the heat pump. The water inlet B12 is the water outlet.

[0043] Due to the presence of silt in seawater, scale deposits form on the walls of the U-shaped heat exchanger tube bundle 14 after prolonged operation of the heat pump unit, affecting the efficiency of the heat exchanger. When cleaning or maintenance is required, it should be carried out as described in Example 2. After cleaning, the heat exchanger parts should be reconnected using threaded fasteners and put back into use.

[0044] The above description is an example of a preferred embodiment of the present utility model. All parts not described in detail are known technologies in the art. The protection scope of the present utility model is determined by the content of the claims. Any equivalent transformations based on the technical teachings of the present utility model are within the protection scope of the present utility model.

Claims

1. A shell-and-tube heat exchanger, wherein the shell-and-tube heat exchanger is horizontally arranged and includes: A tube box, tube sheet, and heat exchanger shell arranged and fixed together in a coaxial direction, wherein a heat exchanger tube bundle is disposed within the heat exchanger shell, characterized in that... The heat exchanger shell is segmented, including heat exchanger shell A and heat exchanger shell B which are detachably and fixedly connected together. Heat exchanger shell A is provided with shell flanges at both ends. Heat exchanger shell B is provided with a shell flange at one end and a closed end at the other end. Heat exchanger shell A and heat exchanger shell B are fastened together by the shell flanges and threaded fasteners. Heat exchanger shell A is provided with water inlet A and heat exchanger shell B is provided with water inlet B. The pipe box is equipped with a partition plate, which divides the inner cavity of the pipe box into a liquid distribution chamber and a gas collection chamber. The pipe box is connected to a refrigerant pipe port A that communicates with the liquid distribution chamber and a refrigerant pipe port B that communicates with the gas collection chamber. The tube sheet is provided with a plurality of tube holes, which are divided into a liquid distribution tube hole area corresponding to the position of the liquid distribution chamber and a gas collection tube hole area corresponding to the position of the gas collection chamber. The area between the liquid distribution tube hole area and the gas collection tube hole area is a tube sheet without holes. A plurality of tube sheet connecting through holes are provided around the periphery of the tube sheet. The shell flange at one end of the heat exchanger shell A, the tube sheet connecting through holes and the tube box are fastened together by threaded fasteners. The heat exchange tube bundle is a U-shaped heat exchange tube bundle, which is supported in the heat exchanger cylinder by a baffle plate. One open end of the U-shaped heat exchange tube bundle is connected to the tube hole in the gas collecting tube hole area and communicates with the gas collecting chamber. The other open end of the U-shaped heat exchange tube bundle is connected to the tube hole in the liquid separating tube hole area and communicates with the liquid separating chamber.

2. The shell-and-tube heat exchanger as described in claim 1, characterized in that, The bottom of the heat exchanger shell A is fixed with bracket A, and the bottom of the heat exchanger shell B is fixed with bracket B.

3. The shell-and-tube heat exchanger as described in claim 1, characterized in that, A sealing gasket A is provided between the tube box and the tube sheet; a sealing gasket B is also provided between the tube sheet and the shell flange of the heat exchanger shell A, and between the shell flange of the heat exchanger shell A and the shell flange of the heat exchanger shell B.

4. The shell-and-tube heat exchanger as described in claim 3, characterized in that, The sealing gasket B includes an annular body, on which a plurality of concentric and evenly distributed gasket through holes are provided.

5. The shell-and-tube heat exchanger as described in claim 3, characterized in that, The sealing gasket A includes an annular body with a plurality of concentric and evenly distributed gasket through holes. A partition is provided inside the annular body along the diameter direction. The partition corresponds to the position of the partition plate in the pipe box. The partition divides the interior of the sealing gasket A into a non-communicating liquid-distributing half-hole and a gas-collecting half-hole. The liquid-distributing half-hole is connected to the liquid-distributing chamber, and the gas-collecting half-hole is connected to the gas-collecting chamber.

6. The shell-and-tube heat exchanger as described in claim 1, characterized in that, The pipe box is a flat pipe box.

7. A seawater aquaculture heat pump unit, wherein the seawater aquaculture heat pump unit comprises: The compressor, condenser, expansion valve, and evaporator are connected by refrigerant pipelines. The evaporator is a shell-and-tube heat exchanger as described in any one of claims 1 to 6. The heat exchanger shell is fixedly connected to the unit frame by threaded fasteners through a support at its bottom. The refrigerant pipe port A is connected to the outlet of the expansion valve, and the refrigerant pipe port B is connected to the inlet of the compressor.

8. The seawater aquaculture heat pump unit as described in claim 7, characterized in that, Water inlet A is the inlet, which is connected to aquaculture wastewater, and water inlet B is the outlet.

9. The seawater aquaculture heat pump unit as described in claim 7, characterized in that, Water inlet A is the water inlet, which connects to fresh seawater, and water inlet B is the water outlet.

Images