A desulfurization tower outlet clean flue gas waste heat utilization device

Abstract

The utility model relates to coal electricity unit desulfurizing tower technical field, and disclose a kind of desulfurizing tower outlet clean flue gas waste heat utilization device, including heat exchanger and heat absorption box, the side surface of heat exchanger is connected with lower bend pipe, the top of lower bend pipe is connected with flexible hose, the top of flexible hose is connected with flue gas connecting pipe, and the one end of heat exchanger is provided with locking assembly, the outside of heat absorption box is provided with water body circulation mechanism, the side surface of heat absorption box is connected with multiple heat absorption ventilation pipes, the side surface of heat absorption box is connected with fan cover, and the one end of each heat absorption ventilation pipe is all through heat absorption box and extends to the inside of fan cover.The desulfurizing tower outlet clean flue gas waste heat utilization device improves the utilization rate of flue gas waste heat, solves the heat recovery of the mode of single serpentine heat absorption pipe and flue gas contact currently, additionally realizes hot water and hot air two energy output simultaneously, avoids heat waste, and improves the practicality of device.

Description

Technical Field

[0001] This utility model relates to the field of desulfurization tower technology for coal-fired power units, specifically a device for utilizing waste heat from the clean flue gas at the outlet of a desulfurization tower. Background Technology

[0002] Desulfurization towers for coal-fired power units are environmental protection devices used in coal-fired power plants to control sulfur dioxide emissions. They remove sulfur dioxide from the flue gas generated by coal-fired power generation, preventing it from forming acid rain and polluting the environment. This ensures that the power plant meets national environmental emission standards and contributes to air pollution prevention and control. To minimize coal consumption and improve the economic efficiency of coal-fired power units, it is necessary to utilize the waste heat of the units as much as possible. The heat in the clean flue gas at the outlet of the desulfurization tower is the complete waste heat of the coal-fired unit, which is emitted into the atmosphere through the chimney. This portion of heat is enormous. Recovering and utilizing the waste heat in the clean flue gas at the outlet of the desulfurization tower can not only improve the efficiency of coal utilization, reduce coal consumption, and reduce the production costs of enterprises, but also promote the consumption of clean energy, which is of great significance for promoting the timely achievement of carbon peaking and carbon neutrality goals.

[0003] Chinese Patent CN217979913U discloses a waste heat recovery device for flue gas used in desulfurization and denitrification spray towers, including a heat recovery box with an air inlet pipe connected to the top of the left side of the heat recovery box. This invention utilizes a combination of a heat-absorbing pipe, a lead screw, a pulley, a belt, a mounting plate, a first motor, a movable plate, a mounting shell, a ring gear, a transmission gear, a drive gear, a second motor, and a cleaning brush. This provides advantages for cleaning the heat-absorbing pipes and solves the problem of existing waste heat recovery devices for desulfurization and denitrification spray towers, which typically heat water in the pipes to achieve heat recovery. During the heat absorption process, the pipes come into contact with the flue gas generated by the desulfurization and denitrification spray tower. However, in the aforementioned patent, waste heat can only be utilized through contact between the heat-absorbing pipe and the flue gas. Since the heat-absorbing pipe is serpentine, the contact area with the flue gas is limited, easily leading to waste of flue gas heat and making it difficult to reuse the flue gas heat, thus reducing the efficiency of waste heat recovery.

[0004] Therefore, we propose a waste heat recovery device for the clean flue gas at the desulfurization tower outlet to solve the problems mentioned above. Utility Model Content

[0005] The purpose of this utility model is to provide a device for utilizing waste heat from the clean flue gas at the outlet of a desulfurization tower, in order to solve the problem mentioned in the background art that currently, when utilizing waste heat from flue gas, it is only possible to utilize waste heat through contact between the heat absorption tube and the flue gas. However, the heat absorption tube is serpentine in shape, so the contact area with the flue gas is limited, which easily leads to the waste of flue gas heat and makes it difficult to reuse the flue gas heat, thus reducing the efficiency of waste heat utilization.

[0006] This utility model provides the following technical solution: a device for utilizing waste heat from clean flue gas at the outlet of a desulfurization tower, comprising a heat exchanger and a heat absorption box. One side of the heat exchanger is connected to a downward bend pipe, the top end of the downward bend pipe is connected to a telescopic flexible hose, the top end of the telescopic flexible hose is connected to a flue gas connecting pipe, one end of the heat exchanger is provided with a locking assembly, the outside of the heat absorption box is provided with a water circulation mechanism, one side of the heat absorption box is connected to multiple heat absorption ventilation pipes, one side of the heat absorption box is connected to a fan shroud, the inner wall of the fan shroud is equipped with an exhaust fan, one end of each heat absorption ventilation pipe penetrates the heat absorption box and extends into the interior of the fan shroud, and the heat absorption ventilation pipe is located on one side of the exhaust fan, the exhaust end of the heat exchanger is connected to an exhaust connecting pipe, one end of the exhaust connecting pipe penetrates the heat absorption box and extends to the top of the heat absorption box.

[0007] Preferably, the water circulation mechanism includes a circulating water pump installed on one side of the heat absorption box. The output end of the circulating water pump is connected to a drain pipe. One end of the drain pipe passes through the heat absorption box and extends into the interior of the heat absorption box. The input end of the circulating water pump is connected to a delivery pipe. One end of the delivery pipe is connected to the outlet end of the heat exchanger. The inlet end of the heat exchanger is connected to an inlet pipe. One end of the inlet pipe passes through the heat absorption box and extends into the interior of the heat absorption box. The upper surface of the heat absorption box is connected to a water injection pipe. The outer surface of the water injection pipe is connected to a solenoid valve.

[0008] Preferably, a threaded air inlet hood is fixedly connected to one side of the heat absorption box, one end of the heat absorption ventilation pipe extends into the interior of the threaded air inlet hood, and an air inlet mesh plate is threadedly connected to the inner ring of the threaded air inlet hood.

[0009] Preferably, the locking assembly includes a support slide mounted at one end of the heat exchanger, a support plate slidably connected to the inner wall of the support slide, one side of the support plate being connected to one side of the flue gas connecting pipe, one end of the flue gas connecting pipe being connected to a connecting flange, a strip-shaped sliding hole being opened on one side of the support slide, a fixing screw being connected to one side of the support plate, one end of the fixing screw passing through the strip-shaped sliding hole and extending to the outside of the strip-shaped sliding hole, and a locking nut being threaded onto the outer surface of the fixing screw.

[0010] Preferably, the upper surface of the heat absorption box is connected to two sets of lifting components, and the bottom surface of the heat exchanger is connected to a mounting bracket.

[0011] This utility model has the following beneficial effects: 1. This desulfurization tower outlet flue gas waste heat recovery device, through the setup of a heat exchanger for initial heat exchange and a heat absorption box for secondary heat exchange, allows the clean flue gas from the desulfurization tower outlet to first enter the heat exchanger via a flue gas connecting pipe, a telescopic flexible hose, and a lower bend pipe. This allows for initial heat exchange with the circulating water, achieving preliminary waste heat recovery. Subsequently, the heat-exchanged flue gas re-enters the heat absorption box through the exhaust connecting pipe, where it undergoes secondary heat exchange with the water. This further absorbs the residual waste heat in the flue gas, increasing the contact time and area between the flue gas and the heat exchange medium, extracting waste heat from the flue gas, and avoiding the heat waste problem caused by the limited contact area in traditional devices. This improves the utilization rate of flue gas waste heat and solves the problem of low waste heat utilization efficiency caused by the current method of using a single serpentine heat absorption tube to contact the flue gas, where the limited contact area between the serpentine tube and the flue gas prevents the effective absorption of a large amount of flue gas heat.

[0012] 2. The waste heat recovery device for the flue gas at the desulfurization tower outlet uses a circulating water pump and inlet pipe to draw water from the heat absorption box and transport it to the inlet of the heat exchanger. After absorbing waste heat from the flue gas in the heat exchanger, the water flows back to the circulating water pump from the outlet through the delivery pipe, and then is discharged back into the heat absorption box through the drain pipe, forming a closed loop and continuously producing hot water to meet the hot water needs of industrial production or daily life. At the same time, the exhaust fan starts running and draws in outside air through the threaded air inlet hood and air inlet mesh plate. When the air flows through multiple heat absorption ventilation pipes into the heat absorption box, it can exchange heat with the water that has been heated to a high temperature in the heat absorption box and be heated to form hot air. This will realize the simultaneous production of both hot water and hot air, avoid heat waste, and improve the practicality of the device. Attached Figure Description

[0013] Figure 1 This is a three-dimensional structural diagram of the present invention viewed from the front; Figure 2 This is a frontal sectional view of the present invention; Figure 3 This is a top sectional view of the heat absorption box in this utility model; Figure 4 This is a side sectional view of the heat absorption box in this utility model; Figure 5 This is a three-dimensional structural diagram of the telescopic flexible hose in this utility model from a side view.

[0014] In the diagram: 1. Heat absorption box; 2. Heat exchanger; 3. Lower bend pipe; 4. Telescopic flexible hose; 5. Flue gas connection pipe; 6. Locking assembly; 61. Support slide; 62. Support slide plate; 63. Strip-shaped sliding hole; 64. Fixing screw; 65. Locking nut; 7. Water circulation mechanism; 71. Circulating water pump; 72. Drain pipe; 73. Conveying pipe; 74. Water inlet pipe; 8. Flue gas connection pipe; 9. Heat absorption ventilation pipe; 10. Threaded air inlet hood; 11. Air inlet mesh plate; 12. Fan hood; 13. Exhaust fan; 14. Water injection pipe; 15. Solenoid valve; 16. Mounting support; 17. Lifting component; 18. Connecting flange. Detailed Implementation

[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model. Example

[0016] Please see Figure 1-5 A device for utilizing waste heat from the clean flue gas at the outlet of a desulfurization tower includes a heat exchanger 2 and a heat absorption box 1. One side of the heat exchanger 2 is connected to a downward bend pipe 3, and the top end of the downward bend pipe 3 is connected to a telescopic hose 4. The top end of the telescopic hose 4 is connected to a flue gas connecting pipe 5. One end of the heat exchanger 2 is provided with a locking component 6. A water circulation mechanism 7 is provided on the outside of the heat absorption box 1. One side of the heat absorption box 1 is connected to multiple heat absorption ventilation pipes 9. One side of the heat absorption box 1 is connected to a fan cover 12. An exhaust fan 13 is installed on the inner wall of the fan cover 12. One end of each heat absorption ventilation pipe 9 passes through the heat absorption box 1 and extends into the inside of the fan cover 12. The heat absorption ventilation pipe 9 is located on one side of the exhaust fan 13. The exhaust end of the heat exchanger 2 is connected to an exhaust connecting pipe 8. One end of the exhaust connecting pipe 8 passes through the heat absorption box 1 and extends to the top of the heat absorption box 1.

[0017] In this embodiment: the clean flue gas discharged from the desulfurization tower enters the device through the flue gas connecting pipe 5, and after being buffered and adjusted by the telescopic flexible hose 4, it is introduced into the heat exchanger 2 through the lower bend pipe 3, where it can exchange heat with the heat exchange medium in the heat exchanger 2. The flue gas after heat exchange is transported to the top of the heat absorption box 1 through the exhaust connecting pipe 8 and enters the heat absorption box 1 for secondary waste heat utilization. In addition, the heat absorption ventilation pipe 9 is used to guide air circulation. When the exhaust fan 13 in the fan cover 12 is started, it can drive the air to flow through the heat absorption ventilation pipe 9, absorb the heat in the heat absorption box 1 to form hot air, and improve the heat exchange efficiency. Example

[0018] This embodiment is an improvement based on Embodiment 1. The water circulation mechanism 7 includes a circulating water pump 71 installed on one side of the heat absorption box 1. The output end of the circulating water pump 71 is connected to a drain pipe 72. One end of the drain pipe 72 passes through the heat absorption box 1 and extends into the interior of the heat absorption box 1. The input end of the circulating water pump 71 is connected to a delivery pipe 73. One end of the delivery pipe 73 is connected to the outlet end of the heat exchanger 2. The inlet end of the heat exchanger 2 is connected to an inlet pipe 74. One end of the inlet pipe 74 passes through the heat absorption box 1 and extends into the interior of the heat absorption box 1. The upper surface of the heat absorption box 1 is connected to a water injection pipe 14. The outer surface of the water injection pipe 14 is connected to a solenoid valve 15.

[0019] In this embodiment: During operation, the circulating water pump 71 draws water from the heat exchanger 2 after absorbing the waste heat of the flue gas through the delivery pipe 73, and then transports the water back to the heat absorption box 1 through the drain pipe 72. At the same time, the water inlet of the heat exchanger 2 draws low-temperature water from the heat absorption box 1 through the water inlet pipe 74, forming a complete closed-loop circulation of water to ensure that the water continuously absorbs the waste heat of the flue gas. In addition, the water injection pipe 14 of the heat absorption box 1 is used to replenish water. The solenoid valve 15 on its surface controls the opening and closing of the water injection pipe 14. When the water level in the heat absorption box 1 is lower than the set value, the solenoid valve 15 opens and water is added to the heat absorption box 1 through the water injection pipe 14 to ensure the stable operation of the water circulation mechanism 7 and avoid the heat exchange effect being affected by insufficient water level. Example

[0020] This embodiment is an improvement on the first embodiment. A threaded air inlet hood 10 is fixedly connected to one side of the heat absorption box 1. One end of the heat absorption ventilation pipe 9 extends into the interior of the threaded air inlet hood 10. An air inlet mesh plate 11 is threadedly connected to the inner ring of the threaded air inlet hood 10. The locking assembly 6 includes a support slide 61 installed at one end of the heat exchanger 2. A support slide plate 62 is slidably connected to the inner wall of the support slide 61. One side of the support slide plate 62 is connected to one side of the flue gas connecting pipe 5. One end of the flue gas connecting pipe 5 is connected to a connecting flange 18. A strip-shaped sliding hole 63 is opened on one side of the support slide 61. A fixing screw 64 is connected to one side of the support slide plate 62. One end of the fixing screw 64 passes through the strip-shaped sliding hole 63 and extends to the outside of the strip-shaped sliding hole 63. A locking nut 65 is threadedly connected to the outer surface of the fixing screw 64. Two sets of lifting parts 17 are connected to the upper surface of the heat absorption box 1. An installation support 16 is connected to the bottom surface of the heat exchanger 2.

[0021] In this embodiment: the air inlet mesh plate 11 filters impurities in the air, preventing them from entering the heat absorption ventilation pipe 9 and causing blockage, thus ensuring smooth airflow. The support slide 61 in the locking assembly 6 can adjust the position of the flue gas connection pipe 5 by sliding the support slide plate 62, facilitating the connection flange 18 at one end of the flue gas connection pipe 5 to connect with the desulfurization tower outlet. The strip-shaped sliding hole 63 on the side of the support slide 61 provides movement space for the fixing screw 64. After the position of the flue gas connection pipe 5 is adjusted to the correct position, tightening the locking nut 65 on the outer surface of the fixing screw 64 can fix the support slide plate 62 in the support slide 61, thereby fixing the flue gas connection pipe 5. In addition, the two sets of lifting components 17 facilitate the lifting and installation of the heat absorption box 1. The mounting bracket 16 on the bottom of the heat exchanger 2 is used to support and fix the heat exchanger 2, ensuring that the entire device is installed stably.

[0022] The working principle of this utility model is as follows: The clean flue gas from the desulfurization tower outlet enters the device through the flue gas connecting pipe 5, and is introduced into the heat exchanger 2 through the telescopic hose 4 and the lower bend pipe 3. Inside the heat exchanger 2, the flue gas and the circulating water complete the first heat exchange, realizing the initial recovery of waste heat. After heat exchange, the flue gas re-enters the heat absorption box 1 through the exhaust pipe 8 to participate in heat exchange again, completing the secondary utilization of waste heat. During the water circulation process, the circulating water pump 71 draws water from the heat absorption box 1 through the inlet pipe 74 and delivers it to the inlet end of the heat exchanger 2. After the heat exchanger 2 absorbs the waste heat of the flue gas, it flows back to the circulating water pump 71 from the outlet end through the delivery pipe 73, and then is discharged back into the heat absorption box 1 through the drain pipe 72, forming a closed loop circulation. When the water level in the heat absorption box 1 is insufficient, the solenoid valve 15 is opened, and water is replenished through the water injection pipe 14 to ensure continuous heat exchange.

[0023] While the flue gas completes secondary heat exchange, the exhaust fan 13 starts running, drawing in outside air through the threaded air inlet hood 10 and the air inlet mesh plate 11. The air flows through multiple heat-absorbing ventilation pipes 9 into the heat-absorbing box 1. At this time, the water in the heat-absorbing box 1 has been heated to a high temperature through two flue gas heat exchanges. When the air flows in the heat-absorbing ventilation pipes 9, it exchanges heat with the high-temperature water outside the pipes and is heated to form hot air, which is finally discharged through the fan hood 12 for subsequent use. This device improves the utilization rate of flue gas waste heat through the combination design of the primary heat exchanger 2 and the secondary heat exchange of the heat-absorbing box 1, and at the same time realizes the production of both hot water and hot air, avoiding heat waste.

[0024] It should be noted that the control method of this utility model is automatic control through a controller. The control circuit of the controller can be implemented by simple programming by those skilled in the art. The power supply is also common knowledge in the field. Furthermore, this utility model is mainly used to protect mechanical devices, so the control method and circuit connection will not be explained in detail here. In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0025] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A device for utilizing waste heat from the clean flue gas at the outlet of a desulfurization tower, comprising a heat exchanger (2) and a heat absorption box (1), characterized in that: One side of the heat exchanger (2) is connected to a lower bend pipe (3), the top end of the lower bend pipe (3) is connected to a telescopic hose (4), the top end of the telescopic hose (4) is connected to a flue gas connection pipe (5), one end of the heat exchanger (2) is provided with a locking assembly (6), the outside of the heat absorption box (1) is provided with a water circulation mechanism (7), one side of the heat absorption box (1) is connected to multiple heat absorption ventilation pipes (9), one side of the heat absorption box (1) is connected to a fan cover (12), the inner wall of the fan cover (12) is equipped with an exhaust fan (13), one end of each heat absorption ventilation pipe (9) penetrates the heat absorption box (1) and extends into the inside of the fan cover (12), and the heat absorption ventilation pipe (9) is located on one side of the exhaust fan (13). The exhaust end of the heat exchanger (2) is connected to an exhaust connecting pipe (8), one end of the exhaust connecting pipe (8) penetrates the heat absorption box (1) and extends to the top of the heat absorption box (1).

2. The device for utilizing waste heat from the outlet flue gas of a desulfurization tower according to claim 1, characterized in that: The water circulation mechanism (7) includes a circulating water pump (71) installed on one side of the heat absorption box (1). The output end of the circulating water pump (71) is connected to a drain pipe (72). One end of the drain pipe (72) passes through the heat absorption box (1) and extends into the interior of the heat absorption box (1).

3. The device for utilizing waste heat from the outlet flue gas of a desulfurization tower according to claim 2, characterized in that: The input end of the circulating water pump (71) is connected to a delivery pipe (73), one end of the delivery pipe (73) is connected to the outlet end of the heat exchanger (2), and the inlet end of the heat exchanger (2) is connected to an inlet pipe (74). One end of the inlet pipe (74) passes through the heat absorption box (1) and extends into the interior of the heat absorption box (1).

4. The device for utilizing waste heat from the outlet flue gas of a desulfurization tower according to claim 1, characterized in that: The upper surface of the heat absorption box (1) is connected to a water injection pipe (14), and the outer surface of the water injection pipe (14) is connected to a solenoid valve (15).

5. The device for utilizing waste heat from the outlet flue gas of a desulfurization tower according to claim 1, characterized in that: A threaded air inlet hood (10) is fixedly connected to one side of the heat absorption box (1), and one end of the heat absorption ventilation pipe (9) extends into the interior of the threaded air inlet hood (10). An air inlet mesh plate (11) is threadedly connected to the inner ring of the threaded air inlet hood (10).

6. The device for utilizing waste heat from the outlet flue gas of a desulfurization tower according to claim 1, characterized in that: The locking assembly (6) includes a support slide (61) installed at one end of the heat exchanger (2), and a support plate (62) is slidably connected to the inner wall of the support slide (61). One side of the support plate (62) is connected to one side of the flue gas connecting pipe (5), and one end of the flue gas connecting pipe (5) is connected to a connecting flange (18).

7. The device for utilizing waste heat from the outlet flue gas of a desulfurization tower according to claim 6, characterized in that: The support slide (61) has a strip-shaped sliding hole (63) on one side, and a fixing screw (64) is connected to one side of the support slide (62). One end of the fixing screw (64) passes through the strip-shaped sliding hole (63) and extends to the outside of the strip-shaped sliding hole (63). A locking nut (65) is threaded onto the outer surface of the fixing screw (64).

8. The device for utilizing waste heat from the outlet flue gas of a desulfurization tower according to claim 1, characterized in that: The upper surface of the heat absorption box (1) is connected to two sets of lifting components (17), and the bottom surface of the heat exchanger (2) is connected to the mounting bracket (16).

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