A spiral baffle heat exchanger

Abstract

The utility model discloses a kind of helical baffle heat exchanger, including shell, heat exchange pipe, the heat exchanger further include helical baffle and center baffle component, the center baffle component includes first center baffle and second center baffle, first center baffle and second center baffle are arranged in helical baffle inside along the central axis of helical baffle, overflow hole is provided on first center baffle, second center baffle is not provided overflow hole, the size of first center baffle is greater than the size of second center baffle.Through setting center baffle component, medium in shell forms complex flow path in helical baffle inside, reduce the situation that dead zone is generated in helical baffle inside, and relative turbulence is generated with outside helical plunger flow, complex flow field is formed in heat exchanger shell, can guarantee under the premise that heat exchanger heat exchange performance is not reduced, substantially improve processing efficiency.

Description

Technical Field

[0001] This utility model relates to the field of shell-and-tube heat exchangers in chemical machinery, specifically to a spiral baffle heat exchanger. Background Technology

[0002] With the advancement of industrialization and the rapid development of emerging industries, the heat exchanger market is gradually expanding. In particular, the demand for heat exchanger equipment is steadily increasing in fields such as chemical, petroleum, power, pharmaceutical, and food industries. At the same time, the demand for high-efficiency heat exchange equipment is also constantly increasing in fields such as new energy and environmental protection. Currently, the annual output of heat exchangers has reached tens of millions of units. Among them, continuous spiral baffle heat exchangers are widely used due to their high heat transfer efficiency, significant energy-saving effect, and low scaling.

[0003] CN113927257B discloses a method for processing a spiral baffle. This method can produce an ideal spiral baffle with a ruled surface, a central spiral that tends to be straight, and all tube holes having cylindrical surfaces parallel to the central axis. However, because the inner spiral of this spiral baffle tends to be straight, the tube holes near the large inclination angle of the inner spiral are very difficult to process. Currently, it can only be processed by wire cutting, which is inefficient. Taking a single spiral baffle with a diameter of 1m and a pitch of 500mm as an example, there are about 20 heat exchange tube holes near the inner spiral that are difficult to process. Using wire cutting, the processing time for a single heat exchange tube hole is about 30 minutes. Therefore, it takes 10 hours to complete the processing of the tube holes near the inner spiral of a single spiral baffle. For a 6m long heat exchanger, about 10 single spiral baffles are generally needed. Processing the tube holes near the inner spiral alone takes 100 hours, resulting in extremely low processing efficiency and high production costs. Furthermore, due to the large deformation and residual stress near the inner spiral of the spiral baffle, the already formed inner pipe hole is easily deformed by heat during the processing of the outer pipe hole, which greatly increases the difficulty of pipe insertion.

[0004] To address the problem of significant curvature changes in the helical surface near the central axis of helical baffles, which makes continuous surface machining and positioning drilling on the curved surface extremely difficult, CN100453951C discloses a combined helical baffle shell-and-tube heat exchanger. This exchanger features a discontinuous inner helical baffle in the central region and a continuous annular outer helical baffle in a region outside the central region that meets machining requirements, forming a combined helical baffle structure. The inner helical baffle is formed by overlapping several fan-shaped or elliptical flat plates, with the outer edge of each inner helical baffle tightly fitted to the outer helical baffle. Furthermore, because the inner helical baffles are arranged helically along the inner helix of the outer helical baffle, overlapping a single inner helical baffle with the outer helical baffle is time-consuming and labor-intensive. Moreover, during operation, since the connection is only edge-to-edge, vibrations in the fluid medium can affect the stability of the inner helical baffle. In addition, the inner spiral baffle is also provided with tube holes for the heat exchange tubes to pass through. However, in order to ensure that the heat exchange tubes pass through smoothly, the inner spiral baffles located at different positions on the inner side of the spiral baffle have different processing angles for the tube holes. This results in the need to design multiple inner spiral baffles with different tube hole opening directions, and the assembly process has a high degree of sequentiality, making it very easy to make mistakes during assembly.

[0005] CN117948817B discloses a centerless spiral baffle heat exchanger. It employs a set of baffle assemblies located at the center of the spiral baffle, inside the baffle, through which heat exchange tubes can pass. The baffle assembly includes a set of irregularly shaped baffles and a set of cross-shaped baffles. These are welded together sequentially to form a spiral arrangement before being fixed to the inner side of the spiral baffle. This design is complex and difficult to manufacture. The irregularly shaped and cross-shaped baffles are connected by welding, and the assemblies themselves are also welded together, making assembly inconvenient and fixing the baffle assembly difficult. Furthermore, the vibration generated by the medium flow during operation can cause the baffle assembly to detach after prolonged use.

[0006] Therefore, there is an urgent need to design a spiral baffle heat exchanger to solve the problems existing in the above-mentioned prior art. Utility Model Content

[0007] The purpose of this invention is to overcome the above-mentioned technical deficiencies and provide a spiral baffle heat exchanger. By optimizing the structure of the spiral baffle, the flow of the medium at the center of the heat exchanger shell is improved and the dead zone is reduced. Thus, without reducing the heat exchange performance of the heat exchanger, the processing efficiency of the baffle is greatly improved and the processing cost is significantly reduced.

[0008] To achieve the above-mentioned technical objectives, the technical solution of this utility model provides:

[0009] A spiral baffle heat exchanger includes a shell and heat exchange tubes. The heat exchanger further includes a spiral baffle and a central baffle assembly. The central baffle assembly includes a first central baffle and a second central baffle. The first central baffle and the second central baffle are disposed on the inner side of the spiral baffle along the central axis of the spiral baffle. The first central baffle is provided with flow holes, while the second central baffle is not provided with flow holes. The size of the first central baffle is larger than the size of the second central baffle.

[0010] Furthermore, both the first and second central baffles are provided with a number of heat exchange tube holes through which the heat exchange tubes pass.

[0011] Furthermore, leakage holes are also provided on the perforated bridge of the first central baffle.

[0012] Furthermore, leakage holes are also provided on the perforated bridge of the second central baffle.

[0013] Furthermore, the flow passage is located at the center of the first central baffle.

[0014] Furthermore, both the first and second central baffles are non-spiral structures. The first central baffle forms a first projection along the axial direction of the spiral baffle, and the second central baffle forms a second projection along the axial direction of the spiral baffle. The first projection is annular, and the second projection is circular or irregular.

[0015] Furthermore, the first projection and the second projection are combined to form the third projection, and the spiral baffle forms a fourth projection along its axial direction. The inner contour of the fourth projection is circular or irregular. The third projection and the fourth projection may partially overlap or not overlap.

[0016] Furthermore, both the first and second central baffles are positioned and fixedly arranged inside the spiral baffles by a combination of tie rods and spacer tubes.

[0017] Furthermore, the shell diameter of the heat exchanger ranges from 100 to 8000 mm.

[0018] Furthermore, the outer diameter of the heat exchanger tubes ranges from 10 to 89 mm.

[0019] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0020] 1. By installing a central baffle assembly with a specific structure inside the heat exchanger, including a first central baffle plate and a second central baffle plate, which are arranged along the central axis of the spiral baffle plate inside the spiral baffle plate, the central baffle assembly has a simple structure and is easy to manufacture. The central baffle assembly blocks the medium flowing in the inner region of the spiral baffle plate, effectively reducing the flow velocity of the medium at the center of the heat exchanger. At the same time, the inner medium accelerates its flow velocity when passing through the flow holes of the first central baffle plate, impacts the second central baffle plate, is blocked by the second central baffle plate, and diffuses outwards. This process repeats, forming a complex flow path inside the spiral baffle plate, reducing the occurrence of dead zones inside the spiral baffle plate. Furthermore, the inner medium can also generate relative turbulence with the spiral plunger flow formed in the outer spiral baffle plate, forming a complex flow field inside the heat exchanger shell, improving the fluid flow state, increasing the degree of turbulence, and greatly improving the surface heat transfer coefficient of the heat exchange tubes. Without reducing the heat exchange performance, the manufacturing cost is significantly reduced. Therefore, the above-mentioned structure can significantly improve processing efficiency without reducing the heat exchanger's heat exchange performance, solving the problem of high processing difficulty and low efficiency of the heat exchange tube holes in the central area of ​​the original spiral baffle. For a baffle assembly with a diameter of 1m and a pitch of 500mm (assuming that a heat exchanger requires 10 spiral baffles), the processing time for all tube holes in the central baffle can be shortened to at least 10 minutes. Compared with the 100-hour processing time for tube holes near the inner spiral line by wire cutting, the processing speed is significantly improved, the processing efficiency is increased, and the processing cost is greatly reduced.

[0021] 2. By providing leakage holes on the perforated bridge of the first and second central baffles, when the medium impacts the first central baffle, it can flow out through the leakage holes, preventing dead zones from forming on the back of the first central baffle; similarly, when the medium impacts the second central baffle, it can flow out through the leakage holes, preventing dead zones from forming on the back of the second central baffle. Furthermore, the high-speed fine stream through the leakage holes further increases the complexity of the medium flow at the center of the heat exchanger shell, effectively improving the heat exchange efficiency at the center of the heat exchanger shell.

[0022] 3. Since multiple first and second central baffles are set along the central axis of the spiral baffle inside the spiral baffle, there is no need to arrange them spirally along the inner spiral line of the spiral baffle, which greatly improves the assembly efficiency. Moreover, both the first and second central baffles can be positioned and fixedly arranged inside the spiral baffle by a combination of tie rods and spacer tubes. There are no extra welding points, and the heat exchange tubes are not easily damaged or detached during long-term use.

[0023] 4. Several heat exchange tubes pass through the central baffle assembly. The central baffle assembly supports the heat exchange tubes passing through it. At the same time, the outer spiral baffle plate can also provide overall support for the heat exchange tube bundle passing through the central baffle assembly, effectively preventing the heat exchange tubes from deforming due to their own weight or vibration caused by the flow of the medium in the shell side.

[0024] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objectives and other advantages of this invention can be realized and obtained through the structures pointed out in the description and the accompanying drawings. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the spiral baffle heat exchanger structure according to an embodiment of the present invention;

[0026] Figure 2 This is a front view of the central baffle assembly in an embodiment of this utility model;

[0027] Figure 3 This is a three-dimensional schematic diagram of the central baffle assembly in an embodiment of this utility model;

[0028] Figure 4 This is a top view of the spiral baffle plate according to an embodiment of the present invention;

[0029] Figure 5 This is a top view of the spiral baffle plate and the central baffle assembly in an embodiment of the present invention.

[0030] The components in the attached diagram are labeled as follows:

[0031] 1. Shell; 2. Tube box; 3. Tube sheet; 4. Heat exchange tube; 5. Spiral baffle; 6. Central baffle assembly; 61. First central baffle; 62. Second central baffle; 7. Heat exchange tube hole. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0033] This utility model embodiment provides a spiral baffle heat exchanger, such as Figure 1-5As shown, the heat exchanger includes a shell 1, heat exchange tubes 4, and a spiral baffle 5 and a central baffle assembly 6. The central baffle assembly includes a first central baffle 61 and a second central baffle 62. The first central baffle 61 and the second central baffle 62 are arranged along the central axis of the spiral baffle 5 inside the spiral baffle 5. The first central baffle 61 is provided with flow holes, while the second central baffle 62 is not provided with flow holes. The size of the first central baffle 61 is larger than the size of the second central baffle 62.

[0034] Preferably, the first central baffle 61 and the second central baffle 62 are alternately arranged on the inner side of the spiral baffle 5 along the central axis of the spiral baffle 5.

[0035] Preferably, the flow passage is located at the center of the first central baffle.

[0036] The spiral baffle 5 is provided with several heat exchange tube holes 7 for the heat exchange tubes 4 to pass through, and the first central baffle 61 and the second central baffle 62 are both provided with several heat exchange tube holes 7 for the heat exchange tubes 4 to pass through.

[0037] Both the first central baffle 61 and the second central baffle 62 are non-spiral structures. Specifically, the non-spiral structure can be a planar structure, an arc structure, or a wave structure. The first central baffle 61 forms a first projection along the axial direction of the spiral baffle 5, and the second central baffle 62 forms a second projection along the axial direction of the spiral baffle 5. The first projection is annular, and the second projection is circular or irregular.

[0038] The union of the first and second projections forms the third projection. The spiral baffle forms a fourth projection along its axial direction. The inner contour of the fourth projection is circular or irregular. The fourth projection may or may not overlap with the third projection. When the outer edge dimension of the central baffle assembly 6 is larger than the inner edge dimension of the spiral baffle 5, the outer edge of the third projection partially overlaps with the fourth projection; when the outer edge dimension of the central baffle assembly 6 is slightly smaller than the inner edge dimension of the spiral baffle 5, the outer edge of the third projection does not overlap with the fourth projection. Figure 5 As shown, when the outer edge shape and size of the central baffle assembly 6 are the same as the inner edge shape and size of the spiral baffle 5, the outer edge of the third projection and the fourth projection are spliced ​​together in a non-overlapping manner to form a complete projection area.

[0039] By incorporating a central baffle assembly 6 with a specific structure within the heat exchanger, comprising a first central baffle plate 61 and a second central baffle plate 62, the central baffle plate 61 and the second central baffle plate 62 are positioned along the central axis of the spiral baffle plate 5 on the inner side of the spiral baffle plate 5. The central baffle assembly 6 has a simple structure and is easy to manufacture. It effectively reduces the flow velocity of the medium flowing in the inner region of the spiral baffle plate 5 by blocking the flow of the medium. Simultaneously, the inner medium experiences increased flow velocity when passing through the flow holes of the first central baffle plate 61, thus reducing the impact on the flow. The fluid impacts the second central baffle 62, is blocked by the second central baffle 61, and diffuses outwards, repeating this process. This creates a complex S-shaped flow path inside the spiral baffle 5, reducing dead zones and allowing the inner medium to interact with the spiral plunger flow formed inside the outer spiral baffle 5. This creates a complex flow field within the heat exchanger shell, improving the fluid's flow state and increasing turbulence. This significantly improves the surface heat transfer coefficient of the heat exchange tube 4, resulting in a substantial reduction in processing costs without compromising heat exchange performance. Therefore, this structure ensures a significant increase in processing efficiency without reducing heat exchanger performance, solving the problems of difficult and inefficient processing of the central region of the original spiral baffle. For a baffle assembly with a diameter of 1m and a pitch of 500mm (assuming a heat exchanger requires 10 spiral baffles), the machining time for all the tube holes of the central baffle can be reduced to at least 10 minutes. Compared to the 100 hours required to machine the tube holes near the inner spiral line by wire cutting, the machining speed is significantly improved, the machining efficiency is increased, and the machining cost is greatly reduced.

[0040] To further increase the complexity of the medium flow at the center of the heat exchanger shell, leakage holes are also provided on the perforated bridge of the first central baffle 61. Preferably, a plurality of leakage holes are provided on the perforated bridge of the first central baffle 61, so that when the medium impacts the first central baffle 61, it can flow out through the leakage holes, preventing dead zones from forming on the back of the first central baffle 61.

[0041] Similarly, leakage holes are also provided on the perforated bridge of the second central baffle 62. Preferably, a plurality of leakage holes are provided on the perforated bridge of the second central baffle 62, so that when the medium impacts the second central baffle 62, it can flow out through the leakage holes, preventing dead zones from forming on the back of the second central baffle 62.

[0042] The aforementioned leakage holes further improve the heat exchange efficiency at the center of the heat exchanger shell.

[0043] like Figure 1As shown, tube sheets 3 are fixedly connected to both ends of the heat exchanger shell 1. Several heat exchange tubes 4, spiral baffles 5, and a central baffle assembly are arranged between the two tube sheets 3. Tube boxes 2 are respectively installed on the outer sides of the two tube sheets 3. The two ends of the heat exchange tubes 4 pass through the two tube sheets 3 and extend into the two tube boxes 2. A tube-side liquid inlet pipe is installed on one tube box 2, and a tube-side liquid outlet pipe is installed on the other tube box 2. Shell-side liquid inlet pipes and shell-side liquid outlet pipes are respectively installed on the side walls of the shell 1.

[0044] The central heat exchange tube bundle passes through the central baffle assembly 6, and the outer ring heat exchange tube bundle passes through the spiral baffle 5. The central baffle assembly 6 supports the heat exchange tubes 4 passing through it, while the outer spiral baffle 5 also provides overall support for the central heat exchange tube bundle passing through the central baffle assembly 6, effectively preventing deformation of the heat exchange tubes 4 due to their own weight or vibration caused by the flow of the medium in the shell side.

[0045] Both the first central baffle 61 and the second central baffle 62 have multiple heat exchange tube holes 7 for heat exchange tubes 4 to pass through. All heat exchange tube holes 7 have the same opening direction and a small deformation curvature. The first central baffle 61 and the second central baffle 62 can be flat or non-flat, such as irregularly shaped curved structures. Regardless of the plate structure, the opening direction of all heat exchange tube holes 7 on the plates is consistent. By ensuring that the opening direction of all heat exchange tube holes 7 on the first central baffle 61 and the second central baffle 62 is consistent, the opening angle of the heat exchange tube holes 7 on the first central baffle 61 and the second central baffle 62 does not need to be repositioned during the opening process, greatly improving the opening efficiency and thus improving the overall production efficiency of the heat exchanger. The heat exchange tube holes 7 on the first central baffle 61 and the second central baffle 62 can be processed using various methods; preferably, the processing method is laser cutting or drilling.

[0046] The angle between the normal of the tangent plane at any point on the first central baffle 61 and the second central baffle 62 and the central axis of the spiral baffle is 0° to 60°. When both the first central baffle 61 and the second central baffle 62 are flat, they can be arranged perpendicular to the central axis of the spiral baffle 5, and the central baffle 6 can also be arranged at an angle relative to the central axis of the spiral baffle 5. Preferably, the angle between the normal of the first central baffle 61 and the second central baffle 62 and the central axis of the spiral baffle is 0°.

[0047] To ensure that the first central baffle 61 and the second central baffle 62 are stably positioned inside the spiral baffle 5, the first central baffle 61 and the second central baffle 62 are respectively positioned using a combination of tie rods and spacers, and are fixedly arranged inside the spiral baffle 5. The spacers ensure that the distance between two adjacent first central baffles 61 or two adjacent second central baffles 62 remains constant, thereby ensuring that the central baffle assembly 6 is stably positioned inside the spiral baffle 5 and avoiding the problem of the central baffle assembly 6 changing position due to fluid impact, which would affect the heat exchange efficiency. Preferably, both the central baffle assembly 6 and the spiral baffle 5 are positioned using a combination of tie rods and spacers.

[0048] The central baffle assembly 6 is arranged in a straight parallel line along the central axis of the spiral baffle plate, eliminating the need for spiral arrangement and significantly improving assembly efficiency. In addition, the first central baffle plate 61 and the second central baffle plate 62 in the central baffle assembly 6 do not need to be welded to the spiral baffle plate, resulting in no extra welding points. This makes them less prone to damage or detachment during long-term use of the heat exchange tube 4.

[0049] The diameter of the heat exchanger shell 1 ranges from 100 to 8000 mm; the outer diameter of the heat exchanger tube 4 ranges from 10 to 89 mm.

[0050] Heat exchanger structures include fixed tube sheet type, U-tube type, floating head type and stuffing box type, etc.

[0051] The present invention provides a spiral baffle heat exchanger in which, during use, medium A enters one side tube box 2 from the tube side inlet pipe, and then medium A flows through the heat exchange tube 4 to exchange heat with medium B, which enters the shell 1 from the shell side inlet pipe. Then medium A enters the other side tube box 2 through the heat exchange tube 4 and flows out from the tube side outlet pipe, while medium B flows out from the shell side outlet pipe.

[0052] Medium B enters the shell 1 through the shell-side inlet. Most of the medium B flows along the spiral channel formed by the spiral baffle 5 to form a spiral plunger flow, which is in full contact with the heat exchange tube 4. A small portion of the medium B enters the inner side of the spiral baffle 5. Since the inner side of the spiral baffle 5 is provided with a central baffle assembly 6, and the central baffle assembly 6 consists of a first central baffle 61 and a second central baffle 62 alternately arranged along the central axis of the spiral baffle, the medium B forms a complex flow path inside the spiral baffle 5, reducing the occurrence of dead zones inside the spiral baffle.

[0053] Specifically, after medium B is blocked by the outer ring of the first central baffle 61, it flows at high speed through its flow holes and impacts the second central baffle 62 located in front. The liquid bypasses the second central baffle 62 and diffuses to its surroundings. Some medium B will flow to the next first central baffle 61, while some medium B will generate relative turbulence on the outer spiral plunger flow, forming a complex flow field in the shell of the heat exchanger. This improves the flow state of the fluid, increases the degree of turbulence, and greatly improves the surface heat transfer coefficient of the heat exchange tube 4.

[0054] Although the present invention has been described in detail 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 of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A spiral baffle heat exchanger, comprising a shell (1) and heat exchange tubes (4), characterized in that, The heat exchanger also includes a spiral baffle (5) and a central baffle assembly (6). The central baffle assembly includes a first central baffle (61) and a second central baffle (62). The first central baffle (61) and the second central baffle (62) are arranged along the central axis of the spiral baffle (5) on the inner side of the spiral baffle (5). The first central baffle (61) is provided with flow holes, while the second central baffle (62) is not provided with flow holes. The size of the first central baffle (61) is larger than the size of the second central baffle (62).

2. The spiral baffle heat exchanger according to claim 1, characterized in that, The first central baffle (61) and the second central baffle (62) are each provided with a plurality of heat exchange tube holes (7) through which the heat exchange tubes (4) pass.

3. The spiral baffle heat exchanger according to claim 2, characterized in that, The first central baffle (61) is also provided with leakage holes on the perforated bridge.

4. The spiral baffle heat exchanger according to claim 2, characterized in that, The second central baffle (62) is also provided with leakage holes on the perforated bridge.

5. The spiral baffle heat exchanger according to claim 1, characterized in that, The flow passage is located at the center of the first central baffle (61).

6. The spiral baffle heat exchanger according to claim 2, characterized in that, Both the first central baffle (61) and the second central baffle (62) are non-spiral structures. The first central baffle (61) forms a first projection along the axial direction of the spiral baffle (5), and the second central baffle (62) forms a second projection along the axial direction of the spiral baffle (5). The first projection is annular, and the second projection is circular or irregular.

7. The spiral baffle heat exchanger according to claim 6, characterized in that, The first projection and the second projection are combined to form the third projection. The spiral baffle (5) forms a fourth projection along its axial direction. The inner contour of the fourth projection is circular or irregular. The third projection and the fourth projection may or may not overlap.

8. The spiral baffle heat exchanger according to claim 1, characterized in that, The first central baffle (61) and the second central baffle (62) are both positioned by a combination of tie rods and spacer tubes and are fixedly arranged inside the spiral baffle (5).

9. The spiral baffle heat exchanger according to claim 1, characterized in that, The diameter of the heat exchanger shell (1) ranges from 100 to 8000 mm.

10. The spiral baffle heat exchanger according to claim 1, characterized in that, The outer diameter of the heat exchange tube (4) of the heat exchanger ranges from 10 to 89 mm.

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