Tube-plate combined type gas-gas heat exchanger

Abstract

The utility model discloses a tube plate combined type gas-gas heat exchanger which comprises an air inlet chamber, an air outlet chamber, a high-temperature heat exchange module, a low-temperature heat exchange plate set and a steering chamber assembly. The high-temperature heat exchange module comprises a high-temperature heat exchange plate set and a high-temperature heat exchange pipe set, an air outlet of the air inlet chamber communicates with the top of the low-temperature heat exchange plate set, and the bottom end of the low-temperature heat exchange plate set communicates with an air inlet of the steering chamber assembly. Two air inlets in the lower portion of the air outlet chamber communicate with the top of the high-temperature heat exchange plate set and the top of the high-temperature heat exchange pipe set correspondingly, and the bottom end of the high-temperature heat exchange plate set and the bottom end of the high-temperature heat exchange pipe set communicate with an air outlet of the steering chamber assembly. According to the utility model, the high-temperature heat exchange tube group, the high-temperature heat exchange plate group and the low-temperature heat exchange plate group are combined, so that a larger heat exchange area can be arranged in the same space, meanwhile, the heat exchange tube group is arranged in front of the heat exchange plate group, and high-temperature flue gas is prevented from being in direct contact with heat exchange plates by utilizing the heat exchange tube group which is more resistant to high temperature; the overall service life of the heat exchanger is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of heat exchanger technology, specifically to a tube sheet combined gas-gas heat exchanger. Background Technology

[0002] In metallurgical heating furnaces, the high-temperature flue gas generated by fuel combustion carries a large amount of heat energy; direct emission would result in serious energy waste. Air preheaters utilize this high-temperature flue gas to heat the combustion air, reducing fuel consumption and pollution emissions. With the metallurgical industry's increasing demands for energy efficiency and environmental protection, higher requirements are being placed on waste heat recovery systems. As the equipment with the highest heat load in the waste heat recovery system, the air preheater plays a crucial role in energy conservation.

[0003] As air preheaters, air-to-air heat exchangers commonly take the form of tubular or plate heat exchangers, using round tubes or flat plates as heat exchange elements. The application of both types of heat exchangers in the high-temperature, confined spaces of metallurgical heating furnace flues is limited by their structural characteristics: tubular heat exchangers have a small heat exchange area that can be arranged within a given space, resulting in lower efficiency; plate heat exchanger plates are difficult to withstand the thermal deformation generated at high temperatures, leading to a short lifespan. Another option is to install protective pipe assemblies before the air preheater, but this reduces the air preheating temperature, requires modifications to the air piping, and occupies a large area. Utility Model Content

[0004] To address the aforementioned problems in the prior art, this utility model provides a tube-sheet combined gas-to-gas heat exchanger, which solves the problem that the heat exchange area that can be arranged in a given space is small.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] A tube-sheet combined air-to-air heat exchanger is provided, comprising an air inlet chamber, an air outlet chamber, a high-temperature heat exchange module, a low-temperature heat exchange plate assembly, and a turning chamber assembly. The high-temperature heat exchange module includes a high-temperature heat exchange plate assembly and a high-temperature heat exchange tube assembly. The air outlet of the air inlet chamber is connected to the top of the low-temperature heat exchange plate assembly, and the bottom of the low-temperature heat exchange plate assembly is connected to the air inlet of the turning chamber assembly. Two air inlets below the air outlet chamber are respectively connected to the top of the high-temperature heat exchange plate assembly and the high-temperature heat exchange tube assembly. The bottoms of both the high-temperature heat exchange plate assembly and the high-temperature heat exchange tube assembly are connected to the air outlet of the turning chamber assembly.

[0007] This invention combines a high-temperature heat exchange tube assembly, a high-temperature heat exchange plate assembly, and a low-temperature heat exchange plate assembly, thereby allowing for a larger heat exchange area to be arranged in the same space. At the same time, the high-temperature heat exchange tube assembly is placed in front of the high-temperature heat exchange plate assembly, using the heat exchange tube assembly that is more resistant to high temperatures to avoid direct contact between high-temperature flue gas and the heat exchange plates, thereby improving the overall lifespan of the heat exchanger.

[0008] Furthermore, a first connecting frame is provided at the top of both the low-temperature heat exchanger plate group and the high-temperature heat exchanger plate group, and a second connecting frame is provided at the bottom of both the low-temperature heat exchanger plate group and the high-temperature heat exchanger plate group. The low-temperature heat exchanger plate group is connected to the air outlet of the air inlet chamber through the first connecting frame and to the air inlet of the deflection chamber assembly through the second connecting frame. The high-temperature heat exchanger plate group is connected to an air inlet below the air outlet chamber through the first connecting frame and to the air outlet of the deflection chamber assembly through the second connecting frame.

[0009] Furthermore, protective side plates are disposed opposite to each other between the first and second connecting frames.

[0010] Furthermore, the top of the high-temperature heat exchanger tube assembly is provided with an upper tube fixing plate for fixing the heat exchanger tubes, and the bottom of the high-temperature heat exchanger tube assembly is provided with a lower tube fixing plate for fixing the heat exchanger tubes; the upper surface of the upper tube fixing plate is provided with a third connecting frame, which is connected to an air inlet below the air outlet chamber; the lower tube fixing plate is connected to the air outlet of the deflection chamber assembly.

[0011] Furthermore, the turning chamber assembly includes a first turning chamber, a second turning chamber, and a third turning chamber; the bottom sides of the second turning chamber are respectively connected to the bottoms of the first turning chamber and the third turning chamber; the top of the first turning chamber is connected to the second connecting frame at the bottom of the low-temperature heat exchange plate group, the top of the second turning chamber is connected to the second connecting frame at the bottom of the high-temperature heat exchange plate group, and the lower tube fixing plate is disposed on the top of the third turning chamber.

[0012] Furthermore, the bottom of the first steering chamber and the bottom of the second steering chamber are connected by an expansion joint.

[0013] Furthermore, a hanger assembly is provided on the air inlet chamber and the air outlet chamber. The hanger assembly includes two first channel steels, the two ends of which are connected by a second channel steel. The first channel steels are installed on the air inlet chamber and the air outlet chamber via connecting plates.

[0014] Furthermore, lifting lugs are provided on the first channel steel.

[0015] This utility model discloses a tube-sheet combined gas-to-gas heat exchanger, the advantages of which are:

[0016] This invention combines a high-temperature heat exchange tube assembly, a high-temperature heat exchange plate assembly, and a low-temperature heat exchange plate assembly, thereby allowing for a larger heat exchange area to be arranged in the same space. Furthermore, the air flow rate in the tubes is small and the temperature is high, achieving more efficient waste heat recovery. At the same time, by placing the high-temperature heat exchange tube assembly in front of the high-temperature heat exchange plate assembly, the use of heat exchange tube assemblies that are more resistant to high temperatures can prevent direct contact between high-temperature flue gas and the heat exchange plates, thereby improving the overall lifespan of the heat exchanger. Attached Figure Description

[0017] Figure 1This is a schematic diagram of the structure of a tube sheet combined gas-gas heat exchanger according to the present invention.

[0018] Figure 2 This is a schematic diagram of the structure of the high-temperature heat exchange plate assembly and the high-temperature heat exchange tube assembly of this utility model.

[0019] Figure 3 This is a schematic diagram of the steering chamber assembly of this utility model.

[0020] The components include: 1. Air inlet chamber; 2. Air outlet chamber; 3. Low-temperature heat exchange plate assembly; 4. Turning chamber assembly; 41. First turning chamber; 42. Second turning chamber; 43. Third turning chamber; 44. Expansion joint; 5. High-temperature heat exchange plate assembly; 6. High-temperature heat exchange tube assembly; 7. First connecting frame; 8. Second connecting frame; 9. Protective side plate; 10. Upper tube fixing plate; 11. Lower tube fixing plate; 12. Third connecting frame; 13. First channel steel; 14. Second channel steel; 15. Connecting plate; 16. Lifting lug. Detailed Implementation

[0021] The present invention is described in detail with respect to specific embodiments in order to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, any changes that are within the spirit and scope of the present invention as defined and determined by the appended claims are obvious. All utility model creations utilizing the concept of the present invention are protected.

[0022] Example 1

[0023] This embodiment provides a tube-sheet combined gas-to-gas heat exchanger, the purpose of which is to solve the problem of the small heat exchange area that can be arranged in a given space in existing heat exchangers. (Refer to...) Figures 1-3 The specific structure of this embodiment will be described in detail below.

[0024] A tube-sheet combined air-to-air heat exchanger includes an air inlet chamber 1, an air outlet chamber 2, a high-temperature heat exchange module, a low-temperature heat exchange plate assembly 3, and a diverting chamber assembly 4.

[0025] The high-temperature heat exchange module includes a high-temperature heat exchange plate assembly 5 and a high-temperature heat exchange tube assembly 6.

[0026] Specifically, the air outlet of the air inlet chamber 1 is connected to the top of the low-temperature heat exchange plate assembly 3, and the bottom of the low-temperature heat exchange plate assembly 3 is connected to the air inlet of the deflection chamber assembly 4.

[0027] The two air inlets below the air outlet chamber 2 are connected to the top of the high-temperature heat exchange plate group 5 and the high-temperature heat exchange tube group 6, respectively. The bottom ends of the high-temperature heat exchange plate group 5 and the high-temperature heat exchange tube group 6 are connected to the air outlet of the turning chamber assembly 4.

[0028] In this embodiment, the high-temperature heat exchange tube assembly 6, the high-temperature heat exchange plate assembly 5, and the low-temperature heat exchange plate assembly 3 are combined, thereby allowing for a larger heat exchange area to be arranged in the same space. Furthermore, the air flow rate in the tubes is small while the temperature is high, achieving more efficient waste heat recovery. Air enters from the air inlet of the air inlet chamber 1, flows through the low-temperature heat exchange plate assembly 3 to the turning chamber assembly 4, then flows through the turning chamber assembly 4 to the high-temperature heat exchange tube assembly 6 and the high-temperature heat exchange plate assembly 5, and finally flows out from the air outlet chamber 2. The high-temperature flue gas sequentially passes through the flue gas side of the high-temperature heat exchange tube assembly 6, the high-temperature heat exchange plate assembly 5, and the low-temperature heat exchange plate assembly 3. The flue gas and air then transfer heat through the plates or tube walls in the high-temperature heat exchange tube assembly 6, the high-temperature heat exchange plate assembly 5, and the low-temperature heat exchange plate assembly 3, thereby heating the air with the flue gas. This achieves a highly efficient, long-term, and stable air preheating effect, thus realizing energy saving in the heating furnace system.

[0029] Meanwhile, in cases where plate heat exchangers are damaged due to thermal deformation at high temperatures, the flue gas temperature is generally above 700℃. By arranging the high-temperature heat exchange tube group 6 in front of the high-temperature heat exchange plate group 5, the high-temperature heat exchange tube group 6, which is more resistant to high temperatures, is used to avoid direct contact between the high-temperature flue gas and the heat exchange plates of the high-temperature heat exchange plate group 5 and the low-temperature heat exchange plate group 3, thereby improving the overall lifespan of the heat exchanger.

[0030] Specifically, a first connecting frame 7 is provided at the top of both the low-temperature heat exchange plate group 3 and the high-temperature heat exchange plate group 5; a second connecting frame 8 is provided at the bottom of both the low-temperature heat exchange plate group 3 and the high-temperature heat exchange plate group 5; the low-temperature heat exchange plate group 3 is connected to the air outlet of the air inlet chamber 1 through the first connecting frame 7, and is connected to the air inlet of the turning chamber assembly 4 through the second connecting frame 8; the high-temperature heat exchange plate group 5 is connected to an air inlet below the air outlet chamber 2 through the first connecting frame 7, and is connected to the air outlet of the turning chamber assembly 4 through the second connecting frame 8.

[0031] In this embodiment, the low-temperature heat exchange plate group 3 and the high-temperature heat exchange plate group 5 use plates with the same structure, which are 600mm long and 1780mm high. The gap between the air side and the flue gas side is 12mm. The high-temperature heat exchange plate group 5 uses 1.2mm thick 310s stainless steel plates, and the low-temperature heat exchange plate group 3 uses 1.0mm thick 321 stainless steel plates. Each heat exchange module contains 55 pairs of plates.

[0032] Fixed slots are provided on the inner sides of the first connecting frame 7 and the second connecting frame 8, and the heat exchange plates of the low-temperature heat exchange plate group 3 and the high-temperature heat exchange plate group 5 are embedded in the fixed slots. The top and bottom of the heat exchange plate pairs are connected to the inner sides of the first connecting frame 7 and the second connecting frame 8 by welding. This allows the two ends of the air flow channel of the low-temperature heat exchange plate group 3 to be connected to the air outlet of the air inlet chamber 1 and the air inlet of the deflection chamber assembly 4, respectively, and the two ends of the air flow channel of the high-temperature heat exchange plate group 5 to be connected to the air inlet of the air outlet chamber 2 and the air outlet of the deflection chamber assembly 4, respectively.

[0033] Specifically, a protective side plate 9 is disposed opposite to the first connecting frame 7 and the second connecting frame 8. The protective side plate 9 provides a certain degree of protection for the heat exchange plates of the low-temperature heat exchange plate group 3 and the high-temperature heat exchange plate group 5.

[0034] Specifically, the top of the high-temperature heat exchanger tube assembly 6 is provided with an upper tube fixing plate 10 for fixing the heat exchanger tubes, and the bottom of the high-temperature heat exchanger tube assembly 6 is provided with a lower tube fixing plate 11 for fixing the heat exchanger tubes; the upper surface of the upper tube fixing plate 10 is provided with a third connecting frame 12, which is connected to an air inlet below the air outlet chamber 2; the lower tube fixing plate 11 is connected to the air outlet of the deflection chamber assembly 4.

[0035] In this embodiment, the high-temperature heat exchange tube group 6 uses round tubes as heat exchange tubes with a height of 1864mm, an outer diameter of 51mm, and a thickness of 3mm. The tubes are bent to absorb deformation. There are 3 rows of tubes in the flue gas flow direction, with 14 round tubes in each row.

[0036] Both the upper tube fixing plate 10 and the lower tube fixing plate 11 have pre-drilled through holes that fit into the high-temperature heat exchange tube assembly 6. The two ends of the heat exchange tubes in the high-temperature heat exchange tube assembly 6 are respectively inserted into the pre-drilled through holes in the upper tube fixing plate 10 and the lower tube fixing plate 11, and are fixed and sealed by welding. This allows each end of the heat exchange tube in the high-temperature heat exchange tube assembly 6 to be connected to the air inlet of the air outlet chamber 2 and the air outlet of the diverting chamber assembly 4, respectively.

[0037] Optionally, the heat exchange tubes in the high-temperature heat exchange tube assembly 6 can be connected to the lower tube fixing plate 11 via an expansion joint. The expansion joint can absorb the expansion deformation of the high-temperature heat exchange tube assembly 6, preventing the turning chamber and heat exchange tubes from deforming and cracking under stress.

[0038] Specifically, the turning chamber assembly 4 includes a first turning chamber 41, a second turning chamber 42, and a third turning chamber 43; the bottom sides of the second turning chamber 42 are respectively connected to the bottoms of the first turning chamber 41 and the third turning chamber 43; the top of the first turning chamber 41 is connected to the second connecting frame 8 at the bottom of the low-temperature heat exchange plate assembly 3, the top of the second turning chamber 42 is connected to the second connecting frame 8 at the bottom of the high-temperature heat exchange plate assembly 5, and the lower tube fixing plate 11 is disposed on the top of the third turning chamber 43.

[0039] Specifically, the bottom of the first steering chamber 41 and the bottom of the second steering chamber 42 are connected by an expansion joint 44.

[0040] In this embodiment, there is also a difference in thermal expansion deformation between the low-temperature heat exchange plate group 3 and the high-temperature heat exchange plate group 5. The bottom of the first turning chamber 41 and the second turning chamber 42 are connected by an expansion joint 44. The expansion joint 44 realizes the soft connection and sealing of the bottom structure of the first turning chamber 41 and the bottom structure of the second turning chamber 42, which can be used normally at high temperature.

[0041] Specifically, hanger assemblies are installed on the air inlet chamber 1 and the air outlet chamber 2. The hanger assemblies include two first channel steels 13, the two ends of which are connected by second channel steels 14. The first channel steels 13 are installed on the air inlet chamber 1 and the air outlet chamber 2 via connecting plates 15. Lifting lugs 16 are provided on the first channel steels 13.

[0042] In this embodiment, the device can be connected to the outside via a hanger assembly. Two first channel steels 13 and two second channel steels 14 are welded together to form a fixed frame. The fixed frame is installed on the air inlet chamber 1 and the air outlet chamber 2 via four connecting plates 15. At the same time, two lifting lugs 16 are provided on the outside of the first channel steel 13, and the device is fixed to the outside via the lifting lugs 16.

[0043] The working principle of a tube-sheet combined gas-to-gas heat exchanger in this scheme is as follows:

[0044] In practical applications, the stacked heat exchange plates in the low-temperature heat exchange plate group 3 and the high-temperature heat exchange plate group 5 alternately divide the space into flue gas flow channels and air flow channels.

[0045] Flue gas enters the heat exchanger from the high-temperature section, passing successively through the outside of the heat exchange tubes of the high-temperature heat exchange tube group 6, the flue gas flow channel of the high-temperature heat exchange plate group 5, and the flue gas flow channel of the low-temperature heat exchange plate group 3 before exiting the heat exchanger. Air enters the heat exchanger from the air inlet chamber 1, passing successively through the air flow channel of the low-temperature heat exchange plate group 3, the turning chamber assembly 4, and the air flow channels of the parallel high-temperature heat exchange plate group 5 and high-temperature heat exchange tube group 6 before exiting the heat exchanger from the air outlet chamber 2. The low-temperature heat exchange plate group 3 constitutes the first flow path, while the parallel high-temperature heat exchange plate group 5 and high-temperature heat exchange tube group 6 constitute the second flow path. Flue gas and air transfer heat through plates or tube walls within the heat exchange modules, with the flue gas heating the air to achieve efficient, long-term, and stable air preheating, thereby realizing energy savings in the heating furnace system.

[0046] Although the specific embodiments of the utility model have been described in detail with reference to the accompanying drawings, this should not be construed as limiting the scope of protection of this patent. Various modifications and variations that can be made by those skilled in the art without inventive effort within the scope described in the claims still fall within the scope of protection of this patent.

Claims

1. A tube-on-tube gas-to-gas heat exchanger, characterized by: The application relates to a high-temperature and low-temperature heat exchange device, which comprises an air inlet chamber (1), an air outlet chamber (2), a high-temperature heat exchange module, a low-temperature heat exchange plate group (3) and a turning chamber assembly (4); the high-temperature heat exchange module comprises a high-temperature heat exchange plate group (5) and a high-temperature heat exchange pipe group (6); An air outlet of the air inlet chamber (1) is communicated with the top of the low-temperature heat exchange plate group (3), and the bottom end of the low-temperature heat exchange plate group (3) is communicated with the air inlet of the turning chamber assembly (4); Two air inlets below the air outlet chamber (2) are respectively communicated with the top of the high-temperature heat exchange plate group (5) and the high-temperature heat exchange pipe group (6), and the bottom ends of the high-temperature heat exchange plate group (5) and the high-temperature heat exchange pipe group (6) are respectively communicated with the air outlet of the turning chamber assembly (4).

2. The tube-in-tube heat exchanger according to claim 1, wherein: The top of the low-temperature heat exchange plate group (3) and the top of the high-temperature heat exchange plate group (5) are respectively provided with first communication frames (7), and the bottom of the low-temperature heat exchange plate group (3) and the bottom of the high-temperature heat exchange plate group (5) are respectively provided with second communication frames (8); The low-temperature heat exchange plate group (3) is communicated with the air outlet of the air inlet chamber (1) through the first communication frame (7) and communicated with the air inlet of the turning chamber assembly (4) through the second communication frame (8); The high-temperature heat exchange plate group (5) is communicated with one air inlet below the air outlet chamber (2) through the first communication frame (7) and communicated with the air outlet of the turning chamber assembly (4) through the second communication frame (8).

3. The tube-in-tube heat exchanger of claim 2, wherein: Protection side plates (9) are arranged oppositely between the first communication frame (7) and the second communication frame (8).

4. The tube-in-tube heat exchanger of claim 2, wherein: The top of the high-temperature heat exchange pipe group (6) is provided with an upper pipe fixing plate (10) for fixing heat exchange pipes, and the bottom of the high-temperature heat exchange pipe group (6) is provided with a lower pipe fixing plate (11) for fixing heat exchange pipes; The upper surface of the upper pipe fixing plate (10) is provided with a third communication frame (12) for communicating with one air inlet below the air outlet chamber (2); The lower pipe fixing plate (11) is communicated with the air outlet of the turning chamber assembly (4).

5. The tube-in-tube heat exchanger of claim 4, wherein: The turning chamber assembly (4) comprises a first turning chamber (41), a second turning chamber (42) and a third turning chamber (43), the bottom of the second turning chamber (42) is communicated with the bottom of the first turning chamber (41) and the bottom of the third turning chamber (43) respectively; The top of the first turning chamber (41) is communicated with the second communication frame (8) at the bottom of the low-temperature heat exchange plate group (3), the top of the second turning chamber (42) is communicated with the second communication frame (8) at the bottom of the high-temperature heat exchange plate group (5), and the lower pipe fixing plate (11) is arranged on the top of the third turning chamber (43).

6. The tube-in-tube heat exchanger of claim 5, wherein: The bottom of the first turning chamber (41) and the bottom of the second turning chamber (42) are communicated through an expansion joint (44).

7. The tube-in-tube heat exchanger of claim 1, wherein: Hanging bracket assemblies are arranged on the air inlet chamber (1) and the air outlet chamber (2), the hanging bracket assembly comprises two first channel steels (13), and the two ends of the two first channel steels (13) are connected through a second channel steel (14); The first channel steel (13) is installed on the air inlet chamber (1) and the air outlet chamber (2) through a connecting plate (15).

8. The tube-in-tube heat exchanger of claim 7, wherein: The first channel steel (13) is provided with an ear (16).

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