Integral spiral finned tube type heat exchanger for roasting furnace

Abstract

The invention discloses an integral spiral finned tube type heat exchanger for a roasting furnace, which belongs to the technical field of heat exchange equipment and comprises a heat exchanger main body, an air inlet pipe and an exhaust pipe are respectively mounted on two sides of the heat exchanger main body through a connecting frame and a fixing bolt, and the closer to the exhaust pipe, the smaller the opening is, and an air delivery pipe is arranged on the outer side of an air guide block. A control system and a driving system are electrically connected among the first temperature sensor, the second temperature sensor, the electric valve and the air pump; high-temperature gas enters the heat exchanger body from the gas inlet pipe, cooling water flows into the spiral finned tube body through the liquid inlet pipe, the high-temperature gas makes full contact with the spiral finned tube body, the retention time of waste gas in the second half spiral finned tube area is shortened, the flow of the liquid inlet pipe can be synchronously adjusted through the electric valve, and the overall heat exchange efficiency is optimized; the device can accurately recognize the problem that the heat exchange efficiency of the spiral finned tube in the second half process is reduced, and exhaust of low-temperature waste gas is accelerated through gas injection, so that the whole heat exchange efficiency is prevented from being affected.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of heat exchange equipment, and particularly relates to a whole spiral finned tube type heat exchanger for a roasting furnace. BACKGROUND

[0002] In the metallurgical, chemical and other industries, the roasting furnace is an important heat energy conversion equipment, and a large amount of high-temperature waste gas is generated in the operation process. According to statistics, the heat contained in the high-temperature waste gas discharged by the roasting furnace accounts for about 30%-50% of the total energy consumption. If this part of waste heat can be efficiently recovered and utilized, not only the production cost of enterprises can be significantly reduced, but also the energy consumption and environmental pollution can be reduced. The spiral finned tube type heat exchanger has become a commonly used equipment in the field of roasting furnace waste heat recovery due to its characteristics of increasing heat exchange area and strengthening heat transfer.

[0003] In the prior art, the traditional spiral finned tube type heat exchanger mainly increases the contact area of the gas and the heat exchange medium through the fin structure to realize heat transfer. Some equipment adopts a fixed air guide structure to guide the flow of high-temperature gas, or controls the flow of the heat exchange medium through simple temperature monitoring.

[0004] However, in the actual application scene of the roasting furnace, the prior art has obvious deficiencies. Firstly, as the gas flows in the heat exchanger, the heat exchange efficiency of the spiral finned tube in the second half of the process is significantly reduced, and the retention of low-temperature waste gas will affect the overall heat exchange effect, resulting in low waste heat recovery efficiency. Secondly, the flow distribution of high-temperature gas in the heat exchanger is uneven, which easily leads to local overheating of the spiral finned tube, especially the finned tube near the gas inlet area which is subjected to high-temperature impact for a long time, accelerating material aging and corrosion and shortening the service life of the equipment. SUMMARY

[0005] In order to overcome the above-mentioned defects, the application provides a whole spiral finned tube type heat exchanger for a roasting furnace, which solves the problem that the heat exchanger in the prior art has a significantly reduced heat exchange efficiency of the spiral finned tube in the second half of the process as the gas flows in the heat exchanger, and the retention of low-temperature waste gas affects the overall heat exchange effect, resulting in low waste heat recovery efficiency.

[0006] To achieve the above objectives, the present invention provides the following technical solution: an integral spiral finned tube heat exchanger for a roasting furnace, comprising a heat exchanger body, an inlet pipe and an outlet pipe respectively installed on both sides of the heat exchanger body via connecting frames and fixing bolts; multiple sets of spiral finned tube bodies snap-fitted inside the heat exchanger body; an inlet pipe and an outlet pipe respectively connected to both ends of the spiral finned tube bodies; an electric valve installed at the inlet pipe opening; a first temperature sensor installed at the outlet pipe opening; and a second temperature sensor for use with the first temperature sensor snap-fitted onto the bottom of the outlet pipe. The heat exchanger body contains a symmetrically arranged air guide block with multiple air nozzles on its inner side. The air guide block is located in the middle of the heat exchanger body near the exhaust pipe, and the air nozzle outlets are V-shaped, with the openings becoming smaller closer to the exhaust pipe. An air supply pipe is provided on the outer side of the air guide block and is fixed to the outer side of the heat exchanger body. An air pump is connected to the air supply pipe through an air inlet. The first temperature sensor and the second temperature sensor are electrically connected to the electric valve and the air pump, forming a control system and a drive system.

[0007] As a further embodiment of the present invention: a fixed frame is installed between the connecting frame and the air intake pipe. A guide plate is rotatably connected within the fixed frame via multiple sets of rotating shafts. The rotating shafts pass through the fixed frame, and gears are fixedly connected to the outer side of the rotating shafts. A rack that cooperates with the gears is slidably connected to the outer side of the fixed frame. A connecting rod is installed on the top of the rack, and a movable plate is snapped onto the outer side of the connecting rod. The connecting rod movably passes through the connecting frame, and the movable plate is located above the connecting frame. A protective block is provided on the top of the air intake pipe, and an electric telescopic rod is installed within the protective block. The output end of the electric telescopic rod is fixedly connected to one side of the bottom of the movable plate. A control system and a drive system are electrically connected between the electric valve and the electric telescopic rod.

[0008] As a further embodiment of the present invention: the connecting frame is fixed to both sides of the heat exchanger body, and multiple sets of fixing bolts are threadedly connected between the connecting frame and the air inlet pipe and the exhaust pipe. A fixing block is installed at the bottom of the exhaust pipe by bolts, and the second temperature sensor is located inside the fixing block.

[0009] As a further embodiment of the present invention: the intake pipe has a slot for use with the fixed frame, the fixed frame has threaded grooves at both ends for use with the fixed bolts, and the top of the intake pipe has a movable groove for use with the connecting rod.

[0010] As a further embodiment of the present invention: a protrusion is provided on the inner side of the rack, and a sliding groove for cooperating with the protrusion is provided on the outer side of the fixing frame on the side of the gear. Multiple sets of support legs are fixedly installed at the bottom of the heat exchanger body.

[0011] As a further aspect of the present invention: the air guide block, the air nozzle, and the air guide plate are all made of high-temperature resistant alloy material, and a sealing block is provided between the fixed frame and the air inlet pipe, the sealing block being made of ceramic fiber material.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. High-temperature gas enters the heat exchanger body through the inlet pipe, while cooling water flows into the spiral finned tube body through the liquid inlet pipe. The high-temperature gas comes into full contact with the spiral finned tube body, transferring heat to the cooling water inside the tube. After absorbing heat, the cooling water temperature rises and is discharged through the liquid outlet pipe, which can be used in other heat-demanding scenarios. After releasing heat, the gas temperature decreases and is discharged through the exhaust pipe. The first temperature sensor monitors the temperature of the hot water in the liquid outlet pipe in real time, and the second temperature sensor monitors the temperature of the exhaust gas in the exhaust pipe in real time. These two temperature data are transmitted to the control system. When the control system detects that the temperature of the exhaust gas in the exhaust pipe is lower than the temperature of the hot water in the liquid outlet pipe, it indicates that the heat exchange efficiency of the latter half of the spiral finned tube has decreased significantly. The control system starts the air pump and delivers gas to the air guide block through the air delivery pipe. The gas is ejected at high speed through the air nozzle in a figure-eight structure to accelerate the discharge of exhaust gas and reduce the residence time of exhaust gas in the latter half of the spiral finned tube area. The electric valve can simultaneously adjust the flow rate of the liquid inlet pipe to optimize the overall heat exchange efficiency. This device can accurately identify the problem of reduced heat exchange efficiency in the latter half of the spiral finned tube and accelerate the discharge of low-temperature exhaust gas through gas injection to avoid affecting the overall heat exchange efficiency. 2. Through control system initialization, the initial opening degree of the electric valve and the initial position of the electric telescopic rod are set according to preset parameters or historical data. At this time, the air guide plate is at the default angle, which is usually in a medium diffusion state. The liquid inlet pipe delivers the cooling medium at the set flow rate. The control system continuously monitors the opening degree of the electric valve to reflect the flow rate of the liquid inlet pipe. The first temperature sensor monitors the temperature of the liquid outlet pipe, and the second temperature sensor monitors the temperature of the exhaust pipe. When the flow rate of the liquid inlet pipe increases, the control system drives the electric telescopic rod to extend. By dynamically adjusting the air guide angle, the high temperature gas is prevented from directly impacting the finned tubes in the central area, so that the gas is more evenly distributed on the cross-section of the heat exchanger, effectively reducing local overheating. Attached Figure Description

[0013] Figure 1 This is a first-view schematic diagram of the overall structure of the present invention; Figure 2 This is a second-view schematic diagram of the overall structure of the present invention; Figure 3 This is a first-view schematic diagram of the cross-sectional structure of the present invention; Figure 4 This is a second-view schematic diagram of the cross-sectional structure of the present invention; Figure 5 This is a schematic cross-sectional view of the heat exchanger body of the present invention; Figure 6 This is a first-view diagram showing the effect of splitting the intake pipe according to the present invention; Figure 7 This is a second-view diagram showing the effect of splitting the air intake pipe according to the present invention.

[0014] In the diagram: 1. Heat exchanger body; 2. Inlet pipe; 3. Exhaust pipe; 4. Spiral finned tube body; 5. Liquid inlet pipe; 6. Liquid outlet pipe; 7. Electric valve; 8. First temperature sensor; 9. Gas delivery pipe; 10. Protective block; 11. Fixing block; 12. Second temperature sensor; 13. Fixing frame; 14. Air guide plate; 15. Gear; 16. Rack; 17. Connecting rod; 18. Slide groove; 19. Electric telescopic rod; 20. Movable plate; 21. Air guide block; 22. Air nozzle; 23. Connecting frame; 24. Slot; 25. Protrusion; 26. Movable groove; 27. Fixing bolt; 28. Support leg. Detailed Implementation

[0015] The technical solution of this patent will be further described in detail below with reference to specific embodiments.

[0016] like Figures 1-7 As shown, the present invention provides a technical solution: An integral spiral finned tube heat exchanger for a roasting furnace includes a heat exchanger body 1. An inlet pipe 2 and an outlet pipe 3 are respectively installed on both sides of the heat exchanger body 1 via connecting frames 23 and fixing bolts 27. Multiple sets of spiral finned tube bodies 4 are snap-fitted into the heat exchanger body 1. An inlet pipe 5 and an outlet pipe 6 are respectively connected to both ends of the spiral finned tube bodies 4. An electric valve 7 is installed at the inlet of the inlet pipe 5, and a first temperature sensor 8 is installed at the outlet of the outlet pipe 6. A second temperature sensor 12, used in conjunction with the first temperature sensor 8, is snap-fitted onto the bottom of the outlet pipe 3. A guide block 21 is fixedly installed in the heat exchanger body 1 with a symmetrical upper and lower structure. Multiple air nozzles 22 are opened on the inner side of the guide block 21. The guide block 21 is located in the middle of the heat exchanger body 1, near the exhaust pipe 3. The air outlet of the air nozzle 22 has an eight-shaped structure, and the opening is smaller as it gets closer to the exhaust pipe 3. An air supply pipe 9 is provided on the outer side of the guide block 21. The air supply pipe 9 is fixed on the outer side of the heat exchanger body 1, and an air pump is connected to the air supply pipe 9 through the air inlet. The first temperature sensor 8 and the second temperature sensor 12 are electrically connected to the electric valve 7 and the air pump, forming a control system and a drive system. Specifically, during use, high-temperature gas enters the heat exchanger body 1 through the inlet pipe 2, and cooling water flows into the spiral finned tube body 4 through the liquid inlet pipe 5. The high-temperature gas comes into full contact with the spiral finned tube body 4, transferring heat to the cooling water inside the tube. After absorbing heat, the cooling water temperature rises and is discharged through the liquid outlet pipe 6, which can be used for other heat-demanding scenarios. After releasing heat, the gas temperature decreases and is discharged through the exhaust pipe 3. The first temperature sensor 8 monitors the temperature of the hot water in the liquid outlet pipe 6 in real time, and the second temperature sensor 12 monitors the temperature of the exhaust gas in the exhaust pipe 3 in real time. These two temperature data are transmitted to the control system. When the control system detects that the temperature of the exhaust gas in the exhaust pipe 3 is lower than the temperature of the hot water in the liquid outlet pipe 6, it indicates that the heat exchange efficiency of the spiral finned tube in the latter half of the process has decreased significantly. The control system starts the air pump and delivers gas to the air guide block 21 through the air delivery pipe 9. The gas passes through the air nozzle 22 at high speed in a figure-eight structure. The gas is ejected to accelerate the discharge of exhaust gas and reduce the residence time of exhaust gas in the latter half of the spiral finned tube area. The electric valve 7 can simultaneously adjust the flow rate of the liquid inlet pipe 5 to optimize the overall heat exchange efficiency. This device can accurately identify the problem of reduced heat exchange efficiency in the latter half of the spiral finned tube and accelerate the discharge of low-temperature exhaust gas through gas injection to avoid affecting the overall heat exchange efficiency. It automatically adjusts based on real-time temperature monitoring data without manual intervention and adapts to different working conditions. The spiral finned tube body 4 increases the heat exchange area and improves the heat conduction efficiency. The position and structural design of the air guide block 21 and the air nozzle 22 (center off the exhaust pipe 3, V-shaped air outlet with the opening smaller closer to the exhaust pipe 3) ensures sufficient heat exchange of gas in the front section and effectively accelerates exhaust in the rear section by recovering heat from the high-temperature gas, reducing energy waste; accelerating the discharge of low-temperature exhaust gas further improves energy utilization. A fixed frame 13 is installed between the connecting frame 23 and the air inlet pipe 2. A guide plate 14 is rotatably connected to the fixed frame 13 through multiple sets of rotating shafts. The rotating shafts pass through the fixed frame 13, and a gear 15 is fixedly connected to the outside of the rotating shafts. A rack 16 that is used in conjunction with the gear 15 is slidably connected to the outside of the fixed frame 13. A connecting rod 17 is installed on the top of the rack 16. A movable plate 20 is snapped on the outside of the connecting rod 17. The connecting rod 17 movably passes through the connecting frame 23. The movable plate 20 is located above the connecting frame 23. A protective block 10 is set on the top of the air inlet pipe 2. An electric telescopic rod 19 is installed inside the protective block 10. The output end of the electric telescopic rod 19 is fixedly connected to one side of the bottom of the movable plate 20. The electric valve 7 and the electric telescopic rod 19 are electrically connected to a control system and a drive system. The connecting frame 23 is fixed to both sides of the heat exchanger body 1. Multiple sets of fixing bolts 27 are threadedly connected between the connecting frame 23, the air inlet pipe 2, and the exhaust pipe 3. A fixing block 11 is installed at the bottom of the exhaust pipe 3 through bolts. The second temperature sensor 12 is located inside the fixing block 11. Specifically, during control system initialization, the initial opening of electric valve 7 and the initial position of electric telescopic rod 19 are set according to preset parameters or historical data. At this time, the air guide plate 14 is at the default angle, usually in a medium diffusion state. The liquid inlet pipe 5 delivers the cooling medium at a set flow rate. The control system continuously monitors the opening of electric valve 7 to reflect the flow rate of liquid inlet pipe 5. The first temperature sensor 8 monitors the temperature of liquid outlet pipe 6, and the second temperature sensor 12 monitors the temperature of exhaust pipe 3. When the flow rate of liquid inlet pipe 5 increases (such as when the heat load demand increases), the control system drives electric telescopic rod 19 to extend, which drives rack 16 to move downward through connecting rod 17. Rack 16 drives gear 15 to rotate, causing air guide plate 14 to open to both sides (increasing the angle), dispersing and guiding the high-temperature gas. When the flow rate of the liquid inlet pipe 5 decreases (e.g., when the heat load decreases), the electric telescopic rod 19 retracts, and the air guide plate 14 moves towards the center (angle decreases), concentrating the airflow to the central finned tubes. During the adjustment process, the control system dynamically adjusts the moving speed of the telescopic rod according to the rate of flow change to avoid over-response. Combining the temperature difference between the exhaust pipe 3 and the liquid outlet pipe 6, the angle of the air guide plate 14 is optimized. If the temperature difference is too large, the diffusion angle of the air guide plate 14 is increased to prolong the gas residence time. If the temperature difference is too small, the diffusion angle is decreased to accelerate the gas flow. With the above structure, by dynamically adjusting the air guide angle, high-temperature gas is prevented from directly impacting the central finned tubes, making the gas distribution more uniform on the heat exchanger cross-section and effectively reducing local overheating. The intake pipe 2 has a slot 24 for use with the fixed frame 13. The fixed frame 13 has threaded grooves at both ends for use with the fixed bolts 27. The top of the intake pipe 2 has a movable groove 26 for use with the connecting rod 17. The inner side of the rack 16 has a protrusion 25. The outer side of the fixed frame 13 has a sliding groove 18 for use with the protrusion 25 on the side of the gear 15. Multiple sets of support legs 28 are fixedly installed at the bottom of the heat exchanger body 1. The air guide block 21, the air nozzle 22, and the air guide plate 14 are all made of high temperature resistant alloy material. A sealing block is provided between the fixed frame 13 and the intake pipe 2. The sealing block is made of ceramic fiber material. Specifically, the slot 24 of the intake pipe 2 engages with the threaded groove of the fixing frame 13, and a detachable connection is achieved through the fixing bolt 27. The movable groove 26 at the top of the intake pipe 2 provides a guide space for the vertical movement of the connecting rod 17, ensuring that the trajectory of the connecting rod 17 is accurate when it drives the rack 16 to slide. Through the mutual cooperation between the protrusion 25 and the slide groove 18, the lateral displacement of the rack 16 is restricted, allowing it to slide vertically along the slide groove 18 only, thus avoiding the lateral force generated when the gear 15 and rack 16 mesh, which would cause wear. The air guide block 21, the air nozzle 22, and the air guide plate 14 are all made of high-temperature resistant alloy materials, which are adapted to the high-temperature gas environment inside the heat exchanger and prevent the metal from failing due to high-temperature oxidation or deformation. The working principle of this invention is as follows: First, high-temperature gas enters the heat exchanger body 1 through the inlet pipe 2, and cooling water flows into the spiral finned tube body 4 through the liquid inlet pipe 5. The two are in full contact through the spiral finned tube body 4. The high-temperature gas transfers heat to the cooling water inside the tube. The heated cooling water is discharged from the liquid outlet pipe 6 for other heat-requiring scenarios, and the cooled gas is discharged from the exhaust pipe 3. The increased heat exchange area of ​​the spiral finned tube body 4 effectively improves the heat transfer efficiency. Secondly, the first temperature sensor 8 and the second temperature sensor 12 monitor the hot water temperature of the liquid outlet pipe 6 and the exhaust gas temperature of the exhaust pipe 3 in real time, and transmit the data to the control system. When the exhaust gas temperature of the exhaust pipe 3 is lower than the hot water temperature of the liquid outlet pipe 6, it indicates that the heat exchange efficiency of the spiral finned tube in the second half of the process has decreased. The control system starts the air pump, and the gas is ejected at high speed through the air supply pipe 9 and the figure-eight-shaped air nozzle 22 of the air guide block 21 to accelerate the exhaust gas discharge. At the same time, according to the flow rate change of the liquid inlet pipe 5, the control system drives the electric telescopic rod 19 to drive the air guide plate 14 to rotate. When the flow rate increases, the air guide plate 14 opens to disperse the airflow, and when the flow rate decreases, the air guide plate 14 closes to concentrate the airflow, so as to achieve uniform gas distribution. It is worth mentioning that the slot 24 of the air intake pipe 2 is matched with the threaded groove of the fixed frame 13, and the fixed bolt 27 achieves a detachable connection, which is convenient for maintenance. The structural design of the movable groove 26, the protrusion 25 and the slide groove 18 ensures that the connecting rod 17 drives the rack 16 to slide accurately, avoiding wear of the gear 15 and rack 16 meshing. In addition, the air guide block 21, the air nozzle 22 and the air guide plate 14 are made of high temperature resistant alloy materials, and the ceramic fiber sealing block between the fixed frame 13 and the air intake pipe 2 ensures airtightness and improves the reliability of the equipment. Finally, the control system integrates the functions of each part and automatically adjusts the air pump, electric valve 7 and electric telescopic rod 19 based on real-time monitoring data. It can adapt to different working conditions without manual intervention. It reduces energy waste by recovering heat from high-temperature gas and further improves energy utilization by accelerating the discharge of low-temperature exhaust gas and optimizing airflow distribution, thus achieving a highly efficient and stable heat exchange process.

[0017] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. An integral spiral finned tube heat exchanger for a roasting furnace, comprising a heat exchanger body (1), characterized in that: The heat exchanger body (1) has an inlet pipe (2) and an outlet pipe (3) installed on both sides via a connecting frame (23) and fixing bolts (27). Multiple sets of spiral finned tube bodies (4) are snapped into the heat exchanger body (1). The two ends of the spiral finned tube bodies (4) are connected to an inlet pipe (5) and an outlet pipe (6). An electric valve (7) is installed at the inlet of the inlet pipe (5). A first temperature sensor (8) is installed at the outlet of the outlet pipe (6). A second temperature sensor (12) for use with the first temperature sensor (8) is snapped into the bottom of the outlet pipe (3). The heat exchanger body (1) is fixedly installed in a symmetrical structure. There is an air guide block (21), and multiple sets of air nozzles (22) are opened on the inner side of the air guide block (21). The air guide block (21) is located in the middle of the heat exchanger body (1) near the exhaust pipe (3), and the air outlet of the air nozzle (22) has an eight-shaped structure. The closer it is to the exhaust pipe (3), the smaller the opening is. An air supply pipe (9) is provided on the outer side of the air guide block (21). The air supply pipe (9) is fixed on the outer side of the heat exchanger body (1), and an air pump is connected to the air supply pipe (9) through the air inlet. The first temperature sensor (8) and the second temperature sensor (12) are electrically connected to the electric valve (7) and the air pump to form a control system and a drive system.

2. The integral spiral finned tube heat exchanger for a roasting furnace according to claim 1, characterized in that: A fixed frame (13) is installed between the connecting frame (23) and the air intake pipe (2). A guide plate (14) is rotatably connected to the fixed frame (13) through multiple sets of rotating shafts. The rotating shafts pass through the fixed frame (13), and a gear (15) is fixedly connected to the outside of the rotating shafts. A rack (16) that works with the gear (15) is slidably connected to the outside of the fixed frame (13). A connecting rod (17) is installed on the top of the rack (16). A movable plate (20) is snapped on the outside of the connecting rod (17). The connecting rod (17) moves through the connecting frame (23). The movable plate (20) is located above the connecting frame (23). A protective block (10) is provided on the top of the air intake pipe (2). An electric telescopic rod (19) is installed inside the protective block (10). The output end of the electric telescopic rod (19) is fixedly connected to one side of the bottom of the movable plate (20). A control system and a drive system are electrically connected between the electric valve (7) and the electric telescopic rod (19).

3. The integral spiral finned tube heat exchanger for a roasting furnace according to claim 2, characterized in that: The connecting frame (23) is fixed on both sides of the heat exchanger body (1). The connecting frame (23) is connected to the air inlet pipe (2) and the exhaust pipe (3) by multiple sets of fixing bolts (27). The bottom of the exhaust pipe (3) is fitted with a fixing block (11) by bolts. The second temperature sensor (12) is located inside the fixing block (11).

4. The integral spiral finned tube heat exchanger for a roasting furnace according to claim 3, characterized in that: The intake pipe (2) has a slot (24) for use with the fixed frame (13), the fixed frame (13) has threaded grooves at both ends for use with the fixed bolts (27), and the top of the intake pipe (2) has a movable groove (26) for use with the connecting rod (17).

5. The integral spiral finned tube heat exchanger for a roasting furnace according to claim 4, characterized in that: The rack (16) has a protrusion (25) on its inner side. The fixed frame (13) has a groove (18) on the outer side of the gear (15) that is used to cooperate with the protrusion (25). The heat exchanger body (1) has multiple sets of support legs (28) fixedly installed at the bottom.

6. The integral spiral finned tube heat exchanger for a roasting furnace according to claim 5, characterized in that: The air guide block (21), the air nozzle (22), and the air guide plate (14) are all made of high-temperature resistant alloy material. A sealing block is provided between the fixed frame (13) and the air inlet pipe (2), and the sealing block is made of ceramic fiber material.

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