Durable high-efficiency indirect heat exchanger hot blast stove

Abstract

The utility model provides a kind of durable high-efficiency indirect heat exchange type hot blast furnace, including internal flue gas flow channel and cold fluid flow channel, flue gas flow channel includes sequentially connected hearth and at least one heat exchanger module, cold fluid flow channel includes the cold fluid jacket that is communicated with the at least one heat exchanger module, and cold fluid jacket is set to hearth outside, cold fluid flow channel and the flue gas flow channel are in the downstream arrangement in hearth area, hearth wallboard temperature is reduced by cold fluid, avoid the problem of hearth oxidation under high temperature, deformation, burn through, improve the durability and reliability of hot blast furnace, cold fluid flow channel and the flue gas flow channel are in the countercurrent arrangement in heat exchanger module area and mutually isolated in heat exchanger module, effectively reduce the exhaust gas temperature of heat exchange type hot blast furnace, improve heat exchange efficiency.

Description

Technical Field

[0001] This utility model relates to the field of hot blast stove technology, and in particular to a durable and efficient indirect heat exchange hot blast stove. Background Technology

[0002] A heat exchanger-type hot air furnace is a device that heats cold air into hot air. It utilizes a metal heat exchanger, based on the principle of heat transfer, to allow high-temperature flue gas and cold air to exchange heat without direct contact, thereby heating the air. Its advantages include a relatively simple structure, effective prevention of combustion products from mixing into the hot air, ensuring the purity of the hot air, and high thermal efficiency. It is widely used in many industrial fields requiring clean hot air, such as chemical, building materials, and food drying, providing a stable and reliable heat source for process flows.

[0003] However, while heat exchange hot air furnaces address the cleanliness issue, they also have many limitations: Firstly, the heat exchange efficiency is low. To extend the service life of the furnace and reduce the temperature of the furnace walls, the mainstream technology adopts a co-current heat exchange method, where the cold fluid first exchanges heat with the furnace and then with the plate or tube heat exchanger downstream of the furnace. Although this method improves the service life of the equipment, the exhaust gas temperature is high and the thermal efficiency is low.

[0004] Secondly, durability and reliability are poor. Although some manufacturers use counter-current heat exchange, the furnace wall temperature is high, approaching or even exceeding the extreme temperature resistance of ordinary stainless steel, making it prone to oxidation, deformation, and burn-through. If a higher-temperature-resistant nickel-based alloy is used for the furnace, the equipment cost will increase significantly.

[0005] Driven by the strong demand for energy conservation and emission reduction, improved industrial energy efficiency and reduced production costs, this study aims to enhance the heat exchange efficiency of heat exchange hot blast stoves while improving their durability and reliability. Utility Model Content

[0006] The technical problem to be solved by this utility model is to overcome the defects of the existing technology. This utility model proposes a durable and efficient indirect heat exchange hot air furnace, which improves the heat exchange efficiency of the hot air furnace without upgrading the furnace chamber material, thereby increasing the service life of the equipment and reducing production costs.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is: a durable and efficient indirect heat exchange hot air furnace, comprising: The flue gas flow channel includes a furnace chamber connected in sequence and at least one heat exchanger module disposed on the side of the furnace chamber; The cold fluid flow channel includes a cold fluid jacket communicating with at least one heat exchanger module; the cold fluid jacket surrounds the outer periphery of the furnace. The cold fluid flow channel and the flue gas flow channel are arranged in a co-current manner in the furnace area, and in a counter-current manner in the heat exchanger module area and are isolated from each other in the heat exchanger module.

[0008] In some embodiments, the heat exchanger module includes at least three stacked heat exchange plates, with two adjacent heat exchange plates being symmetrical based on their contact interface; thus, when both the flue gas flow channel and the cold fluid flow channel pass through the heat exchanger module, they can flow through the cavity enclosed by different heat exchange plates, thereby achieving mutual isolation between the flue gas flow channel and the cold fluid flow channel within the same heat exchanger module.

[0009] In some embodiments, the heat exchange plate includes a plate body and a folded edge segment and a connecting segment disposed based on the edge of the plate body. The connecting segment is parallel to the plate body, and the folded edge segment is folded 30-60° based on the thickness direction of the plate body. The first connecting edge and the second connecting edge are both composed of the folded edge segment and the connecting segment. The first connecting edge and the second connecting edge are respectively disposed based on the length and width directions of the plate body, and the folding directions of the first connecting edge and the second connecting edge are opposite. Therefore, when adjacent heat exchange plates are stacked, they can form a cavity without the aid of additional structures to allow flue gas and cold fluid to pass through. The angle of the folded edge segment can guide the entry and exit of flue gas and cold fluid to a certain extent, reducing the local resistance at the inlet and outlet of the heat exchanger module.

[0010] In some embodiments, a plurality of support points are arrayed on the plate body, the height of the support points being no greater than the distance between the plate body and the connecting section; the support points include a first protrusion and a second protrusion, the first protrusion and the second protrusion having opposite protrusion directions and the first protrusion and the second protrusion being spaced apart on the plate body; therefore, support points can be used to provide support for the middle region of adjacent heat exchange plates when the heat exchange plates are stacked.

[0011] In some embodiments, the cold fluid jacket is provided with at least one baffle plate, which is fixedly connected to the inner wall of the cold fluid jacket and the heat exchanger module. The furnace is disposed in the opening or through hole of the baffle plate, and the baffle plate is configured to divide the cold fluid flow channel into a U-shaped flow channel. Therefore, it can guide the flow direction of the cold fluid flow channel in the high-efficiency indirect heat exchange hot blast stove, and avoid the cold fluid from short-circuiting in the cold fluid jacket to form a heat exchange dead zone, which would lead to furnace deformation and burn-through.

[0012] In some embodiments, the inner cavity of the furnace includes, from bottom to top, a high-temperature section furnace, a medium-temperature section furnace, and a low-temperature section furnace; the baffle plate includes a first baffle plate and a second baffle plate, the first baffle plate being disposed between the high-temperature section furnace and the medium-temperature section furnace; the second baffle plate being disposed between the medium-temperature section furnace and the low-temperature section furnace; thus, it can further prevent the cold fluid from short-circuiting in the cold fluid jacket, forming a heat exchange dead zone, which could lead to furnace deformation and burn-through.

[0013] In some embodiments, the heat exchanger module includes a first heat exchanger module, which further includes a baffle strip configured to divide the first heat exchanger module into a low-temperature zone and a high-temperature zone located on both sides of a second baffle plate. In the cold fluid flow channel, the high-temperature zone is located on the discharge side of the low-temperature zone. Furthermore, the length of the baffle strip is no greater than 2 / 3 of the width of the heat exchange plate; therefore, it can prevent the cold fluid from short-circuiting within the heat exchange plate and forming a heat exchange dead zone.

[0014] In some embodiments, a second heat exchanger module is also included, and there are at least two heat exchanger modules. One end of the first heat exchanger module is connected to the output end of the furnace, and the other end is connected to at least one of the second heat exchanger modules through a connecting pipe equipped with an expansion joint. Therefore, it is possible to complete further countercurrent heat exchange between cold fluid and hot flue gas to improve heat exchange efficiency while absorbing thermal expansion and eliminating thermal stress.

[0015] In some embodiments, both the flue gas flow channel and the cold fluid flow channel are disposed within the frame; the two ends of the flue gas flow channel are respectively connected to the burner interface and the exhaust outlet disposed at the bottom of the frame; the two ends of the cold fluid flow channel are respectively connected to the air inlet and the air outlet disposed on opposite sides of the frame; insulation cotton is filled between the flue gas flow channel and the frame, and between the cold fluid flow channel and the frame; thus, the external temperature of the hot blast stove frame can be kept below the 60°C safety threshold for high-temperature burns, reducing heat loss of the hot blast stove.

[0016] In some embodiments, the width of the connecting pipe and the flue gas outlet are both smaller than the width of the second heat exchanger module, and a sealing plate is provided on at least one side of the connecting pipe and the flue gas outlet. The sum of the widths of the connecting pipe and the sealing plate, and the flue gas outlet and the sealing plate, is equal to the width of the second heat exchanger module; therefore, it is possible to better complete the countercurrent heat exchange between the cold fluid and the hot flue gas to improve the heat exchange efficiency.

[0017] Compared with the prior art, this application has the following beneficial effects: In the technical solution of this application embodiment, the indirect heat exchange hot blast stove includes an internal flue gas flow channel and a cold fluid flow channel. The flue gas flow channel includes a furnace chamber and at least one heat exchanger module connected in sequence. The cold fluid flow channel includes a cold fluid jacket connected to the aforementioned at least one heat exchanger module, and the cold fluid jacket is disposed outside the furnace chamber. The cold fluid flow channel and the flue gas flow channel are arranged in a co-current manner in the furnace chamber area. The cold fluid reduces the temperature of the furnace chamber wall plate, avoiding the problems of furnace chamber oxidation, deformation, and burn-through at high temperatures, thereby improving the durability and reliability of the hot blast stove. The cold fluid flow channel and the flue gas flow channel are arranged in a counter-current manner in the heat exchanger module area and are isolated from each other in the heat exchanger module, effectively reducing the exhaust gas temperature of the heat exchange hot blast stove and improving the heat exchange efficiency. Attached Figure Description

[0018] The disclosure of this utility model is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this utility model. In the drawings, the same reference numerals are used to refer to the same parts. Wherein: Figure 1 This is a structural diagram of a durable and efficient indirect heating furnace. The red line in the diagram indicates the flow direction of the internal flue gas, and the blue line indicates the flow direction of the internal cold fluid. Figure 2 Schematic diagram of the furnace chamber and cold fluid jacket structure of a durable and efficient indirect heating furnace; Figure 3 This is a schematic diagram of the heat exchange plate and baffles; Figure 4 Showing Figure 3 A magnified view of the local structure in region A; Figure 5 This is a schematic diagram of heat exchange plates welded together in pairs.

[0019] The numbers in the diagram are: 1-burner interface, 2-frame, 3-insulation cotton, 4-furnace, 41-high temperature section furnace, 42-medium temperature section furnace, 43-low temperature section furnace, 51-second baffle plate, 52-first baffle plate, 6-air outlet, 7-cylinder, 8-baffle strip, 9-first heat exchanger module, 10-expansion joint, 11-second heat exchanger module, 12-sealing plate, 13-air inlet, 14-exhaust outlet, 15-cold fluid jacket, 16-first connecting edge, 161-folded edge section, 162-connecting section, 17-second connecting edge, 18-first protrusion, 19-second protrusion. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0022] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0023] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0024] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0025] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0026] In this application, "multiple" means two or more (including two).

[0027] Heat exchanger hot air furnaces can be widely used in many industrial fields that require clean hot air, such as chemical industry, building materials, and food drying, to provide a stable and reliable heat source for the process.

[0028] The inventors of this application have noted that the heat exchange efficiency of heat exchange hot air furnaces currently on the market is not high and their durability and reliability are poor.

[0029] The inventors discovered through research that, in order to extend the service life of the furnace chamber 4 and reduce the temperature of the furnace chamber 4 wall plate, the co-current heat exchange method was adopted. Although this improved the service life of the equipment, the exhaust gas temperature was high and the thermal efficiency was low. On the other hand, the counter-current heat exchange method would cause the temperature of the furnace chamber 4 wall to approach or even exceed the limit temperature resistance value of ordinary stainless steel, resulting in oxidation, deformation, burn-through and other conditions. If a more heat-resistant nickel-based alloy were used instead, the equipment cost would increase significantly.

[0030] Based on the problems discovered by the inventors, the inventors designed a durable and efficient indirect heat exchange hot blast stove, including an internal flue gas flow channel and a cold fluid flow channel. The flue gas flow channel includes a furnace chamber 4 and at least one heat exchanger module connected in sequence. The cold fluid flow channel includes a cold fluid jacket 15 connected to the aforementioned at least one heat exchanger module, and the cold fluid jacket 15 is located outside the furnace chamber 4. The cold fluid flow channel and the flue gas flow channel are arranged in a co-current manner in the furnace chamber 4 area. The cold fluid reduces the temperature of the furnace chamber 4 wall plate, avoiding the problems of oxidation, deformation, and burn-through of the furnace chamber 4 at high temperatures, thereby improving the durability and reliability of the hot blast stove. The cold fluid flow channel and the flue gas flow channel are arranged in a counter-current manner in the heat exchanger module area and are isolated from each other in the heat exchanger module, effectively reducing the exhaust gas temperature of the heat exchange hot blast stove and improving the heat exchange efficiency.

[0031] Please see Figure 1 and Figure 2 , Figure 1 This is a schematic diagram of the structure of the durable and efficient indirect heating furnace according to an embodiment of the present invention. Figure 2 A schematic diagram of the structure of the furnace chamber 4 and the cold fluid jacket 15 of a durable and efficient indirect heating furnace.

[0032] This utility model provides a durable and efficient indirect heat exchange hot blast stove, including a flue gas flow channel and a cold fluid flow channel disposed therein. The flue gas flow channel includes a furnace chamber 4 and at least one heat exchanger module connected in sequence. The heat exchanger modules are all disposed on one side of the furnace chamber 4. The furnace chamber 4 and the heat exchanger modules are connected by a cylinder 7, forming a flue gas that first flows from bottom to top, then changes direction to flow laterally through the cylinder 7, and then flows from top to bottom through the at least one heat exchanger module and is discharged. The cold fluid flow channel includes a cold fluid jacket 15 communicating with the at least one heat exchanger module. The cold fluid jacket 15 is disposed outside the furnace chamber 4. The flow direction of the cold fluid flow channel is always upward. The high-temperature hot flue gas mainly transfers heat to the cold fluid through radiation to achieve the gradual cooling of the high-temperature hot flue gas. The cold fluid flow channel and the flue gas flow channel are arranged in the same direction in the furnace 4 area, while they are arranged in the opposite direction in the heat exchanger module area. The cold fluid flowing in the cold fluid flow channel and the high-temperature flue gas flowing in the flue gas flow channel do not come into contact in the heat exchanger module, but the heat exchange process is completed through the heat exchanger module. That is, the cold fluid flow channel and the flue gas flow channel are isolated from each other in the heat exchanger module.

[0033] To achieve the isolation between the aforementioned cold fluid flow channel and flue gas flow channel within the heat exchanger module, in some embodiments, the heat exchanger includes at least three stacked heat exchange plates. Any two adjacent heat exchange plates are symmetrical based on their contact interface. In this embodiment, multiple stacked heat exchange plates need to be edge-sealed by additional side plates. The area enclosed by adjacent heat exchange plates and side plates is called a heat exchange chamber. Each adjacent heat exchange chamber has a heat exchange port. For example, if a heat exchange chamber has heat exchange ports on both sides of its length direction, then the adjacent heat exchange chamber needs to have heat exchange ports on both sides of its width direction.

[0034] Please see Figure 3 , Figure 3 This is a schematic diagram of the heat exchange plate and baffle strip 8.

[0035] In a further embodiment, the aforementioned heat exchange plate includes a plate body and a folded edge section 161 and a connecting section 162 disposed along the edge of the plate body. The connecting section 162 is parallel to the plate body, and the folded edge section 161 is folded at 30-60° along the thickness direction of the plate body. The folding angle of the folded edge section 161 can effectively guide the fluid into the heat exchanger module, effectively reducing the local resistance of cold fluid and flue gas entering and exiting the heat exchanger module. A first connecting edge 16 and a second connecting edge 17 are respectively disposed along the length and width directions of the plate body. Both the first connecting edge 16 and the second connecting edge 17 are composed of the aforementioned folded edge section 161 and connecting section 162, wherein the folding directions of the first connecting edge 16 and the second connecting edge 17 are opposite. When stacking heat exchange plates, either the first connecting edge 16 or the second connecting plate of adjacent heat exchange plates can be arranged opposite each other to achieve a symmetrical arrangement of the two heat exchange plates, thus forming a heat exchange chamber (denoted as the first heat exchange chamber). No additional side plates are needed for edge sealing, and the heat exchange chamber is in a through state along the extension direction of the connecting surface. The heat exchange chamber adjacent to the first heat exchange chamber (denoted as the second heat exchange chamber) is formed in a through state perpendicular to the first heat exchange chamber due to the closure of the other of the first connecting edge 16 or the second connecting edge 17, thereby realizing the isolation of the cold fluid flow channel and the flue gas flow channel in the heat exchanger module.

[0036] In a further embodiment, to enhance the support of the central part of the heat exchange chamber, i.e., the support of adjacent plate components, a plurality of support points are arrayed on the plate. The height of each support point is equal to the distance between the plate and the connecting section 162. When adjacent heat exchange plates are symmetrically stacked, the opposing support points can achieve top contact and provide corresponding support force. The aforementioned support points include a first protrusion 18 and a second protrusion 19. The protrusion directions of the first protrusion 18 and the second protrusion 19 are opposite, and the first protrusion 18 and the second protrusion 19 are spaced apart on the plate. The aforementioned heat exchange plate can be integrally formed by stamping. The opposite protrusion directions of the first protrusion 18 and the second protrusion 19 enable the heat exchange plate to provide support for both sides of the plate when stacked. The integrally formed heat exchange plate can effectively prevent it from tilting and falling off under high temperature and high pressure. The height of the support point is equal to the distance between the plate body and the connecting section 162, which can reduce the deformation of the channel under high temperature and high pressure. The interval setting of the first protrusion 18 and the second protrusion 19 can provide uniform support for the heat exchange plates on both sides at the same time, thereby effectively ensuring the structural stability of the heat exchanger module.

[0037] To prevent short-circuiting of the cold fluid within the heat exchanger plate, which could create a heat exchange dead zone and lead to deformation and burn-through of the furnace 4, the flow direction of the cold fluid in the cold fluid channel needs to be controlled. At least one baffle plate is installed in the cold fluid jacket 15. One end of the first baffle plate 52 is fixed to the inner wall of the cold fluid jacket 15, and the other end is fixedly connected to the edge of the heat exchanger module. The first baffle plate 52 is also fixedly connected to the outer wall of the furnace 4. When the cold fluid enters the cold fluid channel, it can move upwards, but during this upward movement, part of it is blocked by the first baffle plate 52. Therefore, it can flow to the heat exchanger module where the first baffle plate 52 does not block it, and then discharge after completing heat exchange.

[0038] Please see Figure 4 , Figure 4 This is a schematic diagram of heat exchange plates welded together in pairs.

[0039] The first heat exchanger module 9 is fixedly connected to the edge of the first baffle plate 52. The first heat exchanger module 9 is also provided with a baffle strip 8. The cross-sectional structure of the baffle strip 8 is a U-shaped structure, specifically a groove structure in the middle and legs set on both sides of the groove structure. The legs are welded to the plate body, which is firm and not easy to fall off or deform. The baffle strip 8 is set at about 1 / 3 of the upper part of the first heat exchanger module 9 (the area of ​​the heat exchanger module above the baffle strip 8 is the high temperature area, and the area of ​​the heat exchanger module below the baffle strip 8 is the low temperature area). One end of the baffle strip 8 is in contact with the baffle plate, and the length of the baffle strip 8 is not greater than 2 / 3 of the width of the heat exchange plate. This allows the cold fluid flowing in the cold fluid jacket 15 to be reversed at the end of the baffle strip 8 away from the baffle plate, so that it can flow through the first heat exchanger module 9 multiple times to complete the heat exchange process. This further avoids the cold fluid from short-circuiting in the heat exchange plate and forming a heat exchange dead zone.

[0040] It is worth noting that the inner cavity of the furnace 4, from top to bottom, includes a low-temperature section furnace 43, a medium-temperature section furnace 42, and a high-temperature section furnace 41. All three sections—low-temperature 43, medium-temperature 42, and high-temperature 41—are corrugated pipes. The corrugated pipes increase the heat exchange area, absorbing thermal expansion forces and eliminating thermal stress. The aforementioned first baffle plate 52 is located between the medium-temperature section furnace 42 and the high-temperature section furnace 41. A second baffle plate 51 is also provided, located between the low-temperature section furnace 43 and the medium-temperature section furnace 42 and fixed to the outer edge of the furnace 4. One end of the second baffle plate is fixedly connected to the edge of the first heat exchanger module 9. The cold fluid flowing in the cold fluid channel enters from the bottom side of the durable and efficient indirect heat exchange hot air furnace and maintains an upward trend while flowing in the cold fluid channel. During this process, the fluid first undergoes a first reversal via the second baffle plate 51, and then undergoes a second reversal via the first baffle plate 52 and the baffle strip 8 before being discharged.

[0041] In some embodiments, a second heat exchanger module 11 is also provided in the cold fluid flow channel. Like the first heat exchanger module 9, the second heat exchanger module 11 includes at least three stacked heat exchange plates. The difference between the second heat exchanger module 11 and the first heat exchanger module 9 is that the second heat exchanger module 11 does not include the flow-blocking strips 8 disposed between the heat exchange plates. The output end of the second heat exchanger module 11 is connected to the output end of the first heat exchanger module 9 via a connecting pipe, on which an expansion joint 10 is provided to absorb thermal expansion and eliminate thermal stress.

[0042] Please refer to Figure 1 Both the flue gas flow channel and the cold fluid flow channel are located within the frame 2. The two ends of the flue gas flow channel are connected to the burner interface 1 and the exhaust outlet 14 located at the bottom of the frame 2, respectively. The two ends of the cold fluid flow channel are connected to the air inlet 13 and the air outlet 6 located on opposite sides of the frame 2, respectively. The height of the air inlet 13 is lower than that of the air outlet 6. Insulation cotton 3 is filled between the flue gas flow channel and the frame 2, and between the cold fluid flow channel and the frame 2, to keep the external temperature of the hot blast stove frame 2 below the 60°C safety threshold for high-temperature burns, thus reducing heat loss from the hot blast stove.

[0043] It is worth noting that the aforementioned second heat exchanger module 11 is vertically arranged in the frame 2 based on the first heat exchanger module 9. The width of the connecting pipe and the exhaust outlet 14 is smaller than the width of the second heat exchanger. A sealing plate 12 is provided on at least one side of the connecting pipe and the exhaust outlet 14. The sum of the widths of the connecting pipe and the sealing plate 12, the exhaust outlet 14 and the sealing plate 12 is equal to the width of the second heat exchanger module 11. Preferably, the connecting pipe and the exhaust outlet 14 are staggered based on the width direction of the second heat exchanger module 11, and cold fluid is used to cool the flue gas flowing through the second heat exchanger first.

[0044] The working principle of the durable and efficient indirect heating furnace is as follows: Cold fluid enters the second heat exchanger module 11 from the air inlet 13, and the output cold fluid at a lower temperature enters the cold fluid jacket 15. The lower temperature cold fluid exchanges heat through the high temperature section furnace 41 and then enters the medium temperature section furnace 42 through the end of the second baffle plate 51. The temperature rises and it enters the low temperature zone of the first heat exchanger module 9. It then turns through one end of the baffle bar 8 and enters the high temperature zone and low temperature section furnace 43 of the first heat exchanger module 9, and is finally discharged through the air outlet 6. The cold fluid exchanges heat with the flue gas countercurrently in the second heat exchanger module 11 and the first heat exchanger module 9, and exchanges heat with the flue gas cocurrently in the furnace 4 and the cold fluid jacket 15.

[0045] Those skilled in the art will understand that the above embodiments are exemplary and not restrictive. Different technical features appearing in different embodiments can be combined to achieve beneficial effects. Based on a study of the drawings, specification, and claims, those skilled in the art should be able to understand and implement other variations of the disclosed embodiments. In the claims, the term "comprising" does not exclude other means or steps; the indefinite article "a" does not exclude a plurality; the terms "first" and "second" are used to identify names and not to indicate any particular order. No reference numerals in the claims should be construed as limiting the scope of protection. The functionality of multiple parts appearing in the claims can be implemented by a single hardware or software module. The appearance of certain technical features in different dependent claims does not mean that these technical features cannot be combined to achieve beneficial effects.

Claims

1. A durable and efficient indirect heat exchange hot air furnace, characterized in that, include: The flue gas flow channel includes a furnace (4) connected in sequence and at least one heat exchanger module disposed on the side of the furnace (4); The cold fluid flow channel includes a cold fluid jacket (15) communicating with at least one heat exchanger module; the cold fluid jacket (15) surrounds the outer periphery of the furnace (4); The cold fluid flow channel and the flue gas flow channel are arranged in the same direction in the furnace (4) area, and the cold fluid flow channel and the flue gas flow channel are arranged in the opposite direction in the heat exchanger module area and are isolated from each other in the heat exchanger module.

2. The durable and efficient indirect heat exchange hot blast furnace according to claim 1, characterized in that, The heat exchanger module includes at least three stacked heat exchange plates, with two adjacent heat exchange plates being symmetrical based on their contact interface.

3. The durable and efficient indirect heat exchange hot blast furnace according to claim 2, characterized in that, The heat exchange plate includes a plate body and a folded edge section (161) and a connecting section (162) provided based on the edge of the plate body. The connecting section (162) is parallel to the plate body, and the folded edge section (161) is folded 30-60° based on the thickness direction of the plate body. The first connecting edge (16) and the second connecting edge (17) are both composed of the folded edge segment (161) and the connecting segment (162). The first connecting edge (16) and the second connecting edge (17) are respectively set based on the length and width directions of the plate body, and the folding directions of the first connecting edge (16) and the second connecting edge (17) are opposite.

4. The durable and efficient indirect heat exchange hot blast furnace according to claim 3, characterized in that, The plate is provided with a plurality of support points arranged in an array. The height of the support points is not greater than the distance between the plate and the connecting section (162). The support points include a first protrusion (18) and a second protrusion (19). The first protrusion (18) and the second protrusion (19) are in opposite directions and are spaced apart on the plate.

5. The durable and efficient indirect heat exchange hot blast furnace according to claim 3, characterized in that, At least one baffle plate is provided in the cold fluid jacket (15). The baffle plate is fixedly connected to the inner wall of the cold fluid jacket (15) and the heat exchanger module. The furnace (4) is provided in the opening or through hole of the baffle plate. The baffle plate is configured to divide the cold fluid flow channel into a U-shaped flow channel.

6. The durable and efficient indirect heat exchange hot blast furnace according to claim 5, characterized in that, The inner cavity of the furnace (4) includes, from bottom to top, a high-temperature section furnace (41), a medium-temperature section furnace (42), and a low-temperature section furnace (43). The baffle plate includes a first baffle plate (52) and a second baffle plate (51). The first baffle plate (52) is disposed between the high-temperature section furnace (41) and the medium-temperature section furnace (42); the second baffle plate (51) is disposed between the medium-temperature section furnace (42) and the low-temperature section furnace (43).

7. The durable and efficient indirect heat exchange hot blast furnace according to claim 6, characterized in that, The heat exchanger module includes a first heat exchanger module (9), and the first heat exchanger module (9) is further provided with a baffle (8). The baffle (8) is configured to divide the first heat exchanger module (9) into a low-temperature zone and a high-temperature zone located on both sides of the second baffle plate (51). In the cold fluid flow channel, the high-temperature zone is located on the discharge side of the low-temperature zone, and the length of the baffle (8) is not greater than 2 / 3 of the width of the heat exchange plate.

8. The durable and efficient indirect heat exchange hot blast furnace according to claim 7, characterized in that, It also includes a second heat exchanger module (11), which is at least two. One end of the first heat exchanger module (9) is connected to the output end of the furnace (4), and the other end is connected to at least one of the second heat exchanger modules (11) through a connecting pipe with an expansion joint (10).

9. The durable and efficient indirect heat exchange hot blast furnace according to claim 8, characterized in that, Both the flue gas flow channel and the cold fluid flow channel are disposed in the frame (2); The two ends of the flue gas flow channel are respectively connected to the burner interface (1) and the exhaust outlet (14) located at the bottom of the frame (2); the two ends of the cold fluid flow channel are respectively connected to the air inlet (13) and the air outlet (6) located on opposite sides of the frame (2). Thermal insulation cotton (3) is filled between the flue gas flow channel and the frame (2) and between the cold fluid flow channel and the frame (2).

10. The durable and efficient indirect heat exchange hot blast furnace according to claim 9, characterized in that, The width of the connecting pipe and the exhaust outlet (14) is smaller than the width of the second heat exchanger module (11). At least one side of the connecting pipe and the exhaust outlet (14) is provided with a sealing plate (12). The sum of the widths of the connecting pipe and the sealing plate (12), the exhaust outlet (14) and the sealing plate (12) is equal to the width of the second heat exchanger module (11).

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