A feed water preheating energy-saving device for a boiler

Abstract

The present application relates to the technical field of boiler energy-saving equipment, in particular to a feed water preheating energy-saving device for a boiler, comprising a shell, a flue gas shunting mechanism, a feed water heat exchange mechanism, a temperature-sensitive adjusting mechanism, a float protection mechanism and a condensate discharge mechanism; the present application is provided with a bypass flue and a condensing flue, a flue gas shunting mechanism and a temperature-sensitive adjusting mechanism, which solve the problem that the existing condensing boiler feed water preheating device cannot simultaneously consider flue gas condensing latent heat recovery and acidic condensate safe discharge when the feed water temperature changes or there is a large amount of condensate; the temperature-sensitive adjusting mechanism dynamically adjusts the flue gas shunting valve plate, and the float protection mechanism adjusts the flue gas shunting valve plate when the condensate level rises, while increasing the discharge amount, so as to reduce the generation of new condensate and promote the discharge of existing condensate.

Description

Technical Field

[0001] This invention relates to the field of boiler energy-saving equipment technology, specifically to an energy-saving device for preheating feedwater in boilers. Background Technology

[0002] Boilers are widely used in industrial production, heating, and heat energy conversion equipment. During boiler operation, feedwater is usually fed into the boiler and heated to form hot water or steam. To reduce fuel consumption, existing boiler systems often install economizers or feedwater preheaters in the boiler tail flue, allowing the high-temperature flue gas discharged from the boiler to exchange heat with the feedwater, thereby increasing the feedwater temperature before entering the boiler and reducing the heating load on the boiler body.

[0003] In gas-fired boilers or low-sulfur fuel boilers, condensing heat exchange structures are sometimes used to condense water vapor in flue gas on a lower-temperature heat exchange surface and release latent heat, thereby improving the heat recovery effect. When using a condensing feedwater preheating device, the feedwater usually flows inside a closed heat exchange tube, while the flue gas flows outside the heat exchange tube. The water vapor in the flue gas forms condensate on the outer wall of the heat exchange tube, and the condensate is then discharged through a collection tank and a drain pipe.

[0004] However, during actual boiler operation, the boiler load, feedwater temperature, and condensate discharge status will change dynamically and are not completely stable. When the feedwater temperature is too high, the heat exchange tube wall temperature is high, and the water vapor in the flue gas is not easy to condense fully, resulting in insufficient latent heat recovery. When the feedwater temperature is too low or the cold water supply suddenly increases, a lot of acidic condensate may be generated in the condensation flue in a short time. If the condensate is not discharged smoothly, it is easy to remain on the heat exchange surface, liquid collection tank, or near the liquid outlet, causing corrosion, ash accumulation and sludge formation, or liquid blockage.

[0005] Existing technologies typically achieve heat exchange and liquid discharge through fixed flues, fixed heat exchange areas, or separate liquid discharge structures. However, the flue gas condensation intensity and condensate discharge status cannot be adjusted in real time. When the condensate level rises abnormally, the device cannot reduce the amount of flue gas entering the condensation flue in time, nor can it simultaneously enhance the discharge of retained condensate. This makes it difficult for the device to balance latent heat recovery efficiency and safe condensate discharge under abnormal operating conditions, affecting the reliability of the device operation.

[0006] Therefore, an energy-saving device for preheating boiler feedwater is proposed. Summary of the Invention

[0007] The purpose of this invention is to provide an energy-saving device for boiler feedwater preheating, which solves the problem that existing condensing boiler feedwater preheating devices cannot simultaneously achieve the recovery of latent heat of flue gas condensation and the safe discharge of acidic condensate when the feedwater temperature changes or there is a large amount of condensate. The device uses a temperature-sensitive regulating mechanism to dynamically adjust the flue gas diversion valve plate, and a float protection mechanism to adapt and adjust the flue gas diversion valve plate when the condensate level rises, while increasing the discharge volume, thereby reducing the generation of new condensate and promoting the discharge of existing condensate.

[0008] To achieve the above objectives, the present invention provides the following technical solution: An energy-saving device for boiler feedwater preheating includes a shell, a flue gas diversion mechanism, a feedwater heat exchange mechanism, a temperature-sensitive regulating mechanism, a float protection mechanism, and a condensate discharge mechanism. The shell contains a bypass flue and a condensate flue. The flue gas diversion mechanism is located at the flue gas inlet of the shell and is used to change the ratio of flue gas entering the bypass flue and the condensate flue. The feedwater heat exchange mechanism includes a feedwater pipe and an inlet located within the condensate flue. The temperature-sensitive regulating mechanism is connected to the float protection mechanism and is also connected to the flue gas diversion mechanism, adjusting the angle of the flue gas diversion mechanism according to the wall temperature. The float protection mechanism is connected to the condensate discharge mechanism and, when the condensate level rises, drives the flue gas diversion mechanism to move in the direction of increasing the opening of the bypass flue.

[0009] In the above scheme, after the flue gas from the boiler tail enters this device, the flue gas can enter the bypass flue and condensation flue in proportion under the action of the flue gas diversion mechanism. When it is necessary to increase heat recovery, more flue gas enters the condensation flue. The water vapor in the flue gas condenses on the outer wall of the feedwater heat exchange mechanism and releases latent heat. When the condensate level rises abnormally, the float protection mechanism drives the flue gas diversion mechanism to increase the opening of the bypass flue, thereby reducing the amount of flue gas entering the condensation flue and reducing the amount of new condensate generated.

[0010] Preferably, the flue gas diversion mechanism includes a diversion valve plate and an external control shaft; the diversion valve plate is located at the bifurcation of the bypass flue and the condensation flue, and the diversion valve plate is rotatably connected to the housing at a position away from the flue gas inlet.

[0011] In the above scheme, the diversion valve plate rotates by using its rotational connection with the housing as the pivot point. When the diversion valve plate is in different angular positions, the smoke inlet area of ​​the bypass flue and condensation flue near the flue gas inlet changes, thereby changing the proportion of flue gas entering the bypass flue and condensation flue. The external control shaft is used to receive the mechanical driving force transmitted by the temperature-sensitive adjustment mechanism and the float protection mechanism, and drives the diversion valve plate to rotate, so that the diversion valve plate can change its angle according to the wall temperature or condensate level.

[0012] Preferably, the temperature-sensitive adjustment mechanism includes a temperature-sensitive mechanical actuator, a push rod, a telescopic connecting rod, a first drive wheel, a second drive wheel, a third drive wheel, and a connecting column; the push rod is connected to the temperature-sensitive mechanical actuator, and the two ends of the telescopic connecting rod are respectively connected to the push rod and the connecting column, with the connecting column located on one side of the first drive wheel.

[0013] In the above scheme, the temperature-sensitive mechanical actuator is used to sense the wall temperature change in the condensation flue. When the wall temperature changes, the temperature-sensitive mechanical actuator generates a telescopic action and pushes the push rod to move. The push rod drives the connecting column to move through the telescopic connecting rod. Since the connecting column is set on one side of the first drive wheel, the connecting column can drive the first drive wheel to rotate after being subjected to force. Thus, the linear displacement of the temperature-sensitive mechanical actuator drives the first drive wheel to rotate.

[0014] Preferably, the first drive wheel drives the second drive wheel to rotate, the first drive wheel and the second drive wheel are connected by a belt drive, the second drive wheel and the third drive wheel are connected by tooth meshing, and the third drive wheel is connected to the external control shaft by a belt drive.

[0015] In the above scheme, the rotation of the first drive wheel is transmitted to the second drive wheel via a belt. The second drive wheel drives the third drive wheel to rotate through tooth meshing. The third drive wheel further drives the external control shaft to rotate via a belt. Thus, the displacement generated by the temperature-sensitive mechanical actuator is transmitted step by step and converted into the rotation of the external control shaft, so that the diversion valve plate can obtain a more defined adjustment angle. The transmission ratio can be adjusted by different drive wheel diameters or tooth transmission relationships.

[0016] Preferably, the float protection mechanism includes a liquid level float, a float guide rod, a camshaft, a drive rod, and a barrier valve; the barrier valve is connected to the condensate discharge mechanism, the float guide rod is connected to the liquid level float, the camshaft is connected to the float guide rod, and several sets of drive rods are evenly distributed around the outer periphery of the first drive wheel.

[0017] In the above scheme, when the condensate is being discharged normally, the level float is in a low position, and the float protection mechanism does not affect the normal adjustment of the temperature-sensitive regulating mechanism to the first drive wheel. When the condensate level rises, the level float rises with the level and drives the float guide rod to move. The float guide rod drives the camshaft to rotate or swing. After the camshaft cooperates with the drive rod on the outer periphery of the first drive wheel, it can drive the first drive wheel to rotate. Similarly, since the first drive wheel is linked to the diversion valve plate through the second drive wheel, the third drive wheel and the external control shaft, the rise of the level float can drive the diversion valve plate to rotate in the direction of increasing the opening of the bypass flue, thereby reducing the proportion of flue gas entering the condensate flue.

[0018] The barrier valve is connected to the condensate discharge mechanism and is installed in the float protection mechanism. When the liquid level rises, the float protection mechanism can not only change the angle of the diversion valve plate, but also cooperate with the condensate discharge mechanism to change the flow state of the discharge position, so as to assist in the discharge of condensate or restore the discharge state in case of abnormal liquid accumulation.

[0019] Preferably, the condensate discharge mechanism includes a collection tank and a water seal drain pipe; the collection tank is located at the bottom of the housing, the water seal drain pipe is connected to the collection tank, and a barrier valve is located at the water seal drain pipe.

[0020] In the above scheme, the condensate generated in the condensation flue flows into the liquid collection tank at the bottom of the shell under the action of gravity, and is then discharged through the water seal drain pipe connected to the liquid collection tank. The water seal drain pipe can maintain the water seal function while discharging the condensate, reducing the leakage of flue gas along the drain channel. The barrier valve is set at the water seal drain pipe, which can adjust the flow state at the water seal drain pipe when the float protection mechanism is activated, so that the condensate discharge mechanism can adapt to the normal discharge and the protection discharge needs when the liquid level rises.

[0021] Preferably, the flue gas diversion mechanism further includes a reset spring and a limiting block; the reset spring is connected to an external control shaft and is used to drive the diversion valve plate to reset to the position of blocking the bypass flue; two sets of limiting blocks are provided, and the limiting blocks are fixedly connected to the inner wall of the housing.

[0022] In the above scheme, the return spring can apply a return force to the external control shaft, so that the diversion valve plate can return to the preset position after the temperature-sensitive adjustment mechanism or the float protection mechanism is released. The limit block is used to limit the rotation range of the diversion valve plate, so as to avoid excessive rotation of the diversion valve plate, which would affect the normal distribution of the bypass flue and condensate flue, or interfere with the inner wall of the housing, thereby improving the operational stability of the flue gas diversion mechanism.

[0023] Preferably, the diversion valve plate is configured with a first angle position, a second angle position, and a third angle position; the diversion valve plate has the smallest smoke inlet area in the bypass flue when it is in the first angle position; and the diversion valve plate has the largest smoke inlet area in the bypass flue when it is in the third angle position.

[0024] In the above scheme, the first angle position corresponds to the state where the flue gas inlet area is small and the condenser flue gas inlet ratio is large, which is suitable for the working condition where the feedwater heat exchange intensity needs to be increased; the second angle position corresponds to the intermediate adjustment state between the bypass flue and the condenser flue, which is suitable for the working condition where the wall temperature is in the middle range or the flue gas load changes relatively slowly; the third angle position corresponds to the protection state where the flue gas inlet area is the largest, which is suitable for the working condition where the condensate level rises or the wall temperature is low, thus reducing the amount of flue gas entering the condenser flue.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Existing condensing feedwater preheating devices mostly adopt fixed flue gas channels or single bypass regulation structures. When the boiler load, flue gas temperature, or feedwater temperature changes, problems of insufficient condensation or excessive condensation are prone to occur. This invention uses a bypass flue and a condensing flue inside the shell, in conjunction with a flue gas diversion mechanism, to enable the diversion valve plate to change the ratio of flue gas entering the bypass flue and the condensing flue. Through temperature-sensitive mechanical actuators, push rods, telescopic connecting rods, first drive wheels, second drive wheels, third drive wheels, and an external control shaft, the wall temperature change is converted into an angle change of the diversion valve plate. This allows the heat exchange intensity in the condensing flue to be dynamically adjusted according to the wall temperature, improving the stability of feedwater preheating and reducing the occurrence of insufficient condensation or overcooling condensation.

[0026] 2. Existing devices typically rely solely on the drain pipe itself or a level alarm when condensate discharge is obstructed, failing to promptly reduce the generation of new condensate at its source. Therefore, this invention utilizes a combination of a level float, float guide rod, camshaft, and drive rod. When the condensate level in the collection tank rises, a temperature-sensitive adjustment mechanism drives the diversion valve plate to rotate in the direction of increasing the bypass flue opening, thereby reducing the amount of flue gas entering the condensate flue, lowering the rate of new condensate generation, and preventing acidic condensate from continuing to accumulate in the condensate flue and collection tank. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the internal structure of the present invention; Figure 3 This is a schematic diagram of the float protection mechanism of the present invention; Figure 4 This is a schematic diagram of the internal structure of the present invention from another perspective; Figure 5 For the present invention Figure 2 Enlarged view of point A in the middle; Figure 6 For the present invention Figure 2 Enlarged diagram of point B in the middle.

[0028] In the diagram: 100, housing; 101, bypass flue; 102, condensate flue; 200, flue gas diversion mechanism; 201, diversion valve plate; 202, external control shaft; 203, return spring; 204, limit block; 205, first angle position; 206, second angle position; 207, third angle position; 300, water supply heat exchange mechanism; 301, water supply pipe; 302, water inlet; 400, temperature-sensitive regulating mechanism; 40 1. Temperature-sensitive mechanical actuator; 402. Push rod; 403. Telescopic connecting rod; 404. First drive wheel; 405. Second drive wheel; 406. Third drive wheel; 407. Connecting column; 500. Float protection mechanism; 501. Liquid level float; 502. Float guide rod; 503. Camshaft; 504. Drive rod; 505. Barrier valve; 600. Condensate discharge mechanism; 601. Liquid collection tank; 602. Water seal drain pipe. Detailed Implementation

[0029] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0030] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein. Those skilled in the art can obtain other embodiments without departing from the spirit of the invention and without creative effort. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0031] Please see Figures 1 to 6 The present invention provides the following technical solution: An energy-saving device for preheating feedwater in a boiler includes a shell 100, a flue gas diversion mechanism 200, a feedwater heat exchange mechanism 300, a temperature-sensitive regulating mechanism 400, a float protection mechanism 500, and a condensate discharge mechanism 600. The shell 100 includes a bypass flue 101 and a condensate flue 102. The flue gas diversion mechanism 200 includes a diversion valve plate 201, an external control shaft 202, a return spring 203, a limit block 204, a first angle position 205, a second angle position 206, and a third angle position 207. The heating mechanism 300 includes a water supply pipe 301 and a water inlet 302; the temperature-sensitive regulating mechanism 400 includes a temperature-sensitive mechanical actuator 401, a push rod 402, a telescopic connecting rod 403, a first drive wheel 404, a second drive wheel 405, a third drive wheel 406, and a connecting column 407; the float protection mechanism 500 includes a liquid level float 501, a float guide rod 502, a camshaft 503, a drive rod 504, and a barrier valve 505; and the condensate discharge mechanism 600 includes a collection tank 601 and a water seal drain pipe 602.

[0032] In one embodiment of the present invention, the system includes a housing 100, a flue gas diversion mechanism 200, a feedwater heat exchange mechanism 300, a temperature-sensitive regulating mechanism 400, a float protection mechanism 500, and a condensate discharge mechanism 600. A bypass flue 101 and a condensate flue 102 are provided inside the housing 100. The flue gas diversion mechanism 200 is located at the flue gas inlet of the housing 100, the feedwater heat exchange mechanism 300 is located inside the condensate flue 102, the temperature-sensitive regulating mechanism 400 is connected to both the flue gas diversion mechanism 200 and the float protection mechanism 500, and the float protection mechanism 500 is connected to the condensate discharge mechanism 600. The liquid discharge mechanism 600 is connected; after the flue gas from the tail end of the boiler enters the shell 100, it enters the bypass flue 101 and the condensing flue 102 proportionally through the flue gas diversion mechanism 200. When it is necessary to increase the preheating intensity of the feedwater, more flue gas enters the condensing flue 102 and exchanges heat with the feedwater heat exchange mechanism 300. When the condensate level rises abnormally, the float protection mechanism 500 drives the flue gas diversion mechanism 200 to move in the direction of increasing the opening of the bypass flue 101, thereby reducing the amount of flue gas entering the condensing flue 102, reducing the amount of new condensate generated, and promoting the discharge of existing condensate.

[0033] In one embodiment of the present invention, the flue gas diversion mechanism 200 includes a diversion valve plate 201 and an external control shaft 202. The diversion valve plate 201 is disposed at the bifurcation of the bypass flue 101 and the condensation flue 102. The diversion valve plate 201 is rotatably connected to the housing 100 at a position away from the flue gas inlet. The external control shaft 202 is connected to the diversion valve plate 201. The diversion valve plate 201 rotates with its rotatable connection position with the housing 100 as the fulcrum. At different angular positions, the flue gas inlet area of ​​the bypass flue 101 and the condensation flue 102 near the flue gas inlet changes, thereby changing the proportion of flue gas entering the bypass flue 101 and the condensation flue 102.

[0034] In one embodiment of the present invention, the temperature-sensitive adjustment mechanism 400 includes a temperature-sensitive mechanical actuator 401, a push rod 402, a telescopic connecting rod 403, a first drive wheel 404, a second drive wheel 405, a third drive wheel 406, and a connecting column 407. The push rod 402 is connected to the temperature-sensitive mechanical actuator 401, and both ends of the telescopic connecting rod 403 are connected to the push rod 402 and the connecting column 407, respectively. The connecting column 407 is disposed on one side of the first drive wheel 404. The first drive wheel 404 and the second drive wheel 405 are driven by a belt, the second drive wheel 405 and the third drive wheel 406 are connected by tooth meshing, and the third drive wheel 406 is driven by an external control shaft 202 by a belt. After sensing the temperature change of the inner wall of the condensing flue 102, the temperature-sensitive mechanical actuator 401 generates a telescopic action, which drives the first drive wheel 404 to rotate through the push rod 402, telescopic connecting rod 403 and connecting column 407. Then, through the second drive wheel 405, the third drive wheel 406 and the external control shaft 202, the diversion valve plate 201 is driven to rotate, so that the diversion valve plate 201 changes the flue gas distribution ratio between the bypass flue 101 and the condensing flue 102 according to the wall temperature.

[0035] In one embodiment of the present invention, the float protection mechanism 500 includes a liquid level float 501, a float guide rod 502, a camshaft 503, a drive rod 504, and a barrier valve 505; the liquid level float 501 is connected to the float guide rod 502, the float guide rod 502 is connected to the camshaft 503, several sets of drive rods 504 are evenly distributed on the outer periphery of the first drive wheel 404, and the barrier valve 505 is connected to the condensate discharge mechanism 600. When the condensate is being discharged normally, the level float 501 is in a low position, and the float protection mechanism 500 does not affect the normal adjustment of the diversion valve plate 201 by the temperature-sensitive regulating mechanism 400. When the condensate level rises, the level float 501 rises with the level and drives the float guide rod 502 to move. The float guide rod 502 drives the camshaft 503 to rotate or swing. After the camshaft 503 cooperates with the drive rod 504, it pushes the first drive wheel 404 to rotate in a safe direction, so that the diversion valve plate 201 moves in the direction of increasing the opening of the bypass flue 101, thereby reducing the proportion of flue gas entering the condensate flue 102.

[0036] In one embodiment of the present invention, the condensate discharge mechanism 600 includes a collection tank 601 and a water seal discharge pipe 602. The collection tank 601 is located at the bottom of the housing 100, and the water seal discharge pipe 602 is connected to the collection tank 601. A barrier valve 505 is located at the water seal discharge pipe 602. The condensate generated in the condensate flue 102 flows into the collection tank 601 under gravity and is then discharged through the water seal discharge pipe 602. The water seal discharge pipe 602 maintains a water seal while discharging the condensate, reducing the leakage of flue gas along the discharge channel. When the condensate level rises, the float protection mechanism 500 can drive the barrier valve 505 to change the flow state at the water seal discharge pipe 602, thereby increasing the discharge volume and improving the discharge recovery capacity under abnormal liquid accumulation conditions.

[0037] As one embodiment of the present invention, the flue gas diversion mechanism 200 further includes a reset spring 203 and a limiting block 204; the reset spring 203 is connected to the external control shaft 202 and is used to drive the diversion valve plate 201 to reset to the position of blocking the bypass flue 101; two sets of limiting blocks 204 are provided, and the limiting blocks 204 are fixedly connected to the inner wall of the housing 100. The diversion valve plate 201 is configured with a first angle position 205, a second angle position 206, and a third angle position 207. When the diversion valve plate 201 is at the first angle position 205, the smoke inlet area of ​​the bypass flue 101 is at its minimum. When the diversion valve plate 201 is at the second angle position 206, the bypass flue 101 and the condensation flue 102 are in an intermediate distribution state. When the diversion valve plate 201 is at the third angle position 207, the smoke inlet area of ​​the bypass flue 101 is at its maximum. The reset direction and rotation range of the diversion valve plate 201 are limited by the reset spring 203 and the limit block 204 to prevent the diversion valve plate 201 from rotating excessively or interfering with the inner wall of the housing 100.

[0038] Working principle: After the flue gas from the tail end of the boiler enters the shell 100, it first reaches the bifurcation position of the bypass flue 101 and the condensing flue 102. The diversion valve plate 201 changes its angle according to the driving force transmitted by the temperature-sensitive regulating mechanism 400 or the float protection mechanism 500, thereby changing the ratio of flue gas entering the bypass flue 101 and the condensing flue 102. The feedwater enters the feedwater pipe 301 through the inlet 302. The flue gas entering the condensing flue 102 exchanges heat with the feedwater pipe 301. The water vapor in the flue gas condenses on the outer wall of the feedwater pipe 301 or in the heat exchange area of ​​the condensing flue 102 and releases latent heat to achieve feedwater preheating and flue gas waste heat recovery.

[0039] Specifically, when the inner wall temperature of the condensing flue 102 is too high, the temperature-sensitive mechanical actuator 401 generates a corresponding extension and retraction action and pushes the push rod 402 to move. The push rod 402 drives the connecting column 407 to move through the extension and retraction connecting rod 403. The connecting column 407 drives the first drive wheel 404 to rotate. The first drive wheel 404 drives the second drive wheel 405 to rotate through the belt. The second drive wheel 405 drives the third drive wheel 406 to rotate through tooth meshing. The third drive wheel 406 then drives the external control shaft 202 to rotate through the belt, so that the diversion valve plate 201 is adjusted to decrease or increase the opening of the bypass flue 101, so that the amount of smoke entering the condensing flue 102 can be mechanically and dynamically adjusted according to the wall temperature change. The temperature-sensitive mechanical actuator 401 can rotate the diversion valve plate 201 to the second angle position 206.

[0040] When the condensate level in the collection tank 601 is maintained within the normal range, the level float 501 is in a lower position, the float guide rod 502 and the camshaft 503 do not push the drive rod 504, and the condensate is stably discharged through the water seal drain pipe 602. When the condensate discharge is not smooth or the amount of condensate generated is too large, causing the level to rise, the level float 501 floats up and drives the float guide rod 502 to move. The float guide rod 502 drives the camshaft 503 to move. The camshaft 503 pushes the drive rod 504 on the outer periphery of the first drive wheel 404, causing the first drive wheel 404 to rotate in the direction of increasing the opening of the bypass flue 101. Similarly, the second drive wheel 405, the third drive wheel 406 and the external control shaft 202 drive the diversion valve plate 201 to rotate to a position close to the third angle position 207, thereby reducing the amount of flue gas entering the condensate flue 102 and reducing the rate of new condensate generation.

[0041] As the level float 501 rises, the float protection mechanism 500 also drives the isolation valve 505 to change the flow state at the water seal drain pipe 602, so that the condensate in the collection tank 601 can be discharged with a larger discharge volume. As the condensate level drops, the level float 501 falls back, the camshaft 503 releases the pressure on the drive rod 504, and the reset spring 203 drives the diversion valve plate 201 back to the preset adjustment position through the external control shaft 202. The isolation valve 505 returns to the normal discharge state, thereby enabling the device to switch between normal condensation heat exchange, wall temperature regulation and abnormal liquid accumulation protection.

[0042] The above embodiments are only used to illustrate some examples of the implementable technical solutions of the present invention and are not intended to limit the implementation. The present invention can be understood in more detail by referring to the embodiments. Those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the scope of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An energy-saving device for preheating feedwater in a boiler, characterized in that: The system includes a housing (100), a flue gas diversion mechanism (200), a feedwater heat exchange mechanism (300), a temperature-sensitive regulating mechanism (400), a float protection mechanism (500), and a condensate discharge mechanism (600). A bypass flue (101) and a condensate flue (102) are provided within the housing (100). The flue gas diversion mechanism (200) is located at the flue gas inlet of the housing (100) and is used to change the ratio of flue gas entering the bypass flue (101) and the condensate flue (102). The feedwater heat exchange mechanism (300) includes components located within the housing (100). The condensate flue (102) includes a water supply pipe (301) and a water inlet (302); the temperature-sensitive regulating mechanism (400) is connected to the float protection mechanism (500); the temperature-sensitive regulating mechanism (400) is connected to the flue gas diversion mechanism (200) and adjusts the angle of the flue gas diversion mechanism (200) according to the wall temperature; the float protection mechanism (500) is connected to the condensate discharge mechanism (600) and drives the flue gas diversion mechanism (200) to move in the direction of increasing the opening of the bypass flue (101) when the liquid level of the condensate rises.

2. The energy-saving device for preheating feedwater in a boiler according to claim 1, characterized in that: The flue gas diversion mechanism (200) includes a diversion valve plate (201) and an external control shaft (202); the diversion valve plate (201) is located at the bifurcation of the bypass flue (101) and the condensation flue (102), and the diversion valve plate (201) is rotatably connected to the housing (100) away from the flue gas inlet.

3. The energy-saving device for preheating feedwater in a boiler according to claim 2, characterized in that: The temperature-sensitive adjustment mechanism (400) includes a temperature-sensitive mechanical actuator (401), a push rod (402), a telescopic connecting rod (403), a first drive wheel (404), a second drive wheel (405), a third drive wheel (406), and a connecting column (407); the push rod (402) is connected to the temperature-sensitive mechanical actuator (401), and the two ends of the telescopic connecting rod (403) are respectively connected to the push rod (402) and the connecting column (407), and the connecting column (407) is located on one side of the first drive wheel (404).

4. The energy-saving device for preheating feedwater in a boiler according to claim 3, characterized in that: The first drive wheel (404) drives the second drive wheel (405) to rotate. The first drive wheel (404) and the second drive wheel (405) are connected by a belt. The second drive wheel (405) and the third drive wheel (406) are connected by tooth meshing. The third drive wheel (406) and the external control shaft (202) are connected by a belt.

5. The energy-saving device for preheating feedwater in a boiler according to claim 3 or 4, characterized in that: The float protection mechanism (500) includes a liquid level float (501), a float guide rod (502), a camshaft (503), a drive rod (504), and a barrier valve (505); the barrier valve (505) is connected to the condensate discharge mechanism (600), the float guide rod (502) is connected to the liquid level float (501), the camshaft (503) is connected to the float guide rod (502), and several sets of drive rods (504) are evenly distributed on the outer periphery of the first drive wheel (404).

6. The energy-saving device for preheating feedwater in a boiler according to claim 5, characterized in that: The condensate discharge mechanism (600) includes a collection tank (601) and a water seal drain pipe (602); the collection tank (601) is located at the bottom of the housing (100), the water seal drain pipe (602) is connected to the collection tank (601), and the barrier valve (505) is located at the water seal drain pipe (602).

7. The energy-saving device for preheating feedwater in a boiler according to claim 4 or 6, characterized in that: The flue gas diversion mechanism (200) also includes a return spring (203) and a limiting block (204); the return spring (203) is connected to the external control shaft (202) and is used to drive the diversion valve plate (201) to return to the position of blocking the bypass flue (101); there are two sets of limiting blocks (204), and the limiting blocks (204) are fixedly connected to the inner wall of the housing (100).

8. The energy-saving device for preheating feedwater in a boiler according to claim 7, characterized in that: The diversion valve plate (201) is configured with a first angle position (205), a second angle position (206), and a third angle position (207). When the diversion valve plate (201) is in the first angle position (205), the smoke inlet area of ​​the bypass flue (101) is the smallest. When the diversion valve plate (201) is in the third angle position (207), the smoke inlet area of ​​the bypass flue (101) is the largest.

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