A device for preventing low-temperature corrosion of a tubular air preheater

Abstract

The utility model discloses a device that prevents low temperature corrosion of tubular air preheater, specifically relates to tubular air preheater technical field, including air preheater main part, both side end surfaces of air preheater main part are equipped with water storage tank, and the middle part of air preheater main part upper end is equipped with a plurality of first temperature detector, and the lower extreme of water storage tank is equipped with a plurality of second temperature detector and a plurality of reflux pipe. The utility model actual use, through in the corresponding setting state of first temperature detector, water storage tank, reflux pipe, small -size water pump, second temperature detector and backwater pipe, the sulfuric acid steam of boiler discharge will make the heat transfer medium temperature of air preheater main part inside continuously increase when entering the inside of air preheater main part, and small -size water pump can guide the cold water of water storage tank inside into the inside of air preheater main part, thereby make the heat transfer medium of air preheater main part inside maintain at proper temperature, avoid causing low temperature corrosion to the inside of air guide pipe.

Description

Technical Field

[0001] This utility model relates to the field of tubular air preheater technology, and more specifically, to a device for preventing low-temperature corrosion of tubular air preheaters. Background Technology

[0002] An air preheater, also known simply as an air preheater, is a preheating device used to improve the heat exchange performance of a boiler and reduce heat loss. The function of an air preheater is to recover and utilize the heat carried in the flue gas discharged from the boiler's tail flue. In the operation of a tubular air preheater, the high-temperature flue gas enters the preheater and its temperature decreases after heat exchange. The flue gas contains a large amount of water vapor. Additionally, sulfur in the fuel produces sulfur dioxide after combustion, and a small amount of sulfur dioxide is further oxidized to sulfur trioxide. Sulfur trioxide combines with water vapor in the flue gas to form sulfur. This process of recovering flue gas can easily cause low-temperature corrosion of the tubular air preheater. Therefore, improvements to the tubular air preheater are necessary to address this issue.

[0003] For example, patent CN222578292U discloses a structure for preventing low-temperature corrosion of an air preheater, including air preheater tubes, tube sheets, side plates, and a flow guiding assembly; a plurality of air preheater tubes are arranged in a vertical array, and the air preheater tubes are used to introduce high-temperature flue gas; two tube sheets are respectively connected to the top and bottom ends of the plurality of air preheater tubes; two side plates are connected to two tube sheets to form a rectangular cross-section air duct, and the air preheater tubes are all located in the air duct, and the air inlet direction of the air preheater tubes is orthogonal to the air inlet direction of the air duct; the flow guiding assembly is disposed on the tube sheet near the exhaust port of the air preheater tube and located on the side of the air inlet in the air duct, and the flow guiding assembly is used to shield the end of the plurality of air preheater tubes near the exhaust port on the side of the air inlet in the air duct.

[0004] When the above-mentioned device is in operation, it prevents the flue gas in the air preheater tube from being cooled below the dew point, thereby preventing the flue gas from condensing in the air preheater tube and causing corrosion. However, when the flue gas flows inside the guide element, it is easy to cause corrosion of the guide element. When the heat exchange efficiency of the guide element for the flue gas is slow, it will also cause low-temperature corrosion of the air preheater tube, thereby damaging the guide element. Utility Model Content

[0005] In order to overcome the above-mentioned defects of the prior art, the present invention provides a device for preventing low-temperature corrosion of tubular air preheaters. The technical problem to be solved by the present invention is: how to avoid low-temperature corrosion of tubular air preheaters.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a device for preventing low-temperature corrosion of a tubular air preheater, comprising an air preheater body, water storage tanks provided on both ends of the air preheater body, a plurality of first temperature detectors provided in the middle of the upper end of the air preheater body, and a plurality of second temperature detectors and a plurality of return pipes provided at the lower end of the water storage tanks.

[0007] The upper end of the water storage tank is provided with multiple return water pipes, the outer end face of the water storage tank is provided with multiple heat dissipation fins, and the outer end face of the return pipe is provided with a small water pump.

[0008] In a preferred embodiment, the lower end of the air preheater body is provided with two bottom brackets, and the connection between the water storage tank and the air preheater body is provided with multiple supporting connecting plates.

[0009] In a preferred embodiment, an air inlet hood is installed at one end of the air preheater body, and an air inlet pipe is provided at the middle of the outer end of the air inlet hood.

[0010] In a preferred embodiment, the air preheater body has an air outlet hood at the end away from the air inlet hood, and the outer end face of the air outlet hood has a plurality of air outlet pipes.

[0011] In a preferred embodiment, a plurality of air guide pipes are provided at the connection between the air preheater body and the air outlet hood, and the air guide pipes penetrate through the end face of the air preheater body.

[0012] In a preferred embodiment, a drain pipe is provided in the middle of the lower end of the air preheater body, and a water supply pipe is provided on one side of the upper end of the air preheater body;

[0013] Both the first and second temperature detectors are electrically connected to an external control device via wires. Both the first and second temperature detectors are commercially available MIK-WZP threaded resistance temperature sensors.

[0014] In a preferred embodiment, the air preheater body and the water storage tank are connected by a return pipe and a return water pipe, and the small water pumps are electrically connected to external control equipment via wires.

[0015] The technical effects and advantages of this utility model are as follows:

[0016] In practical use, this invention, with the corresponding setup of the first temperature detector, water storage tank, return pipe, small water pump, second temperature detector, and return water pipe, can detect the temperature of the internal heat exchange medium of the air preheater body and the water storage tank through the first and second temperature detectors. When the sulfuric acid vapor discharged from the boiler enters the interior of the air preheater body, it will cause the temperature of the heat exchange medium inside the air preheater body to rise continuously. After reaching a certain temperature, the heat exchange efficiency will decrease. The small water pump can introduce cold water from the water storage tank into the interior of the air preheater body, thereby maintaining the heat exchange medium inside the air preheater body at a suitable temperature. This avoids the sulfuric acid vapor from directly contacting the cold wall of the air duct and condensing into sulfuric acid, thus avoiding low-temperature corrosion inside the air duct. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0018] Figure 2 This is a schematic diagram of the overall structure of this utility model from a bottom view.

[0019] Figure 3 This utility model Figure 2 Enlarged view of section A.

[0020] Figure 4 This is a schematic diagram of the overall right-side cross-sectional structure of this utility model.

[0021] The attached figures are labeled as follows: 1 Air preheater body, 2 Water tank, 3 Bottom support, 4 Air inlet hood, 5 Air inlet pipe, 6 First temperature detector, 7 Air outlet hood, 8 Water supply pipe, 9 Water return pipe, 10 Air duct, 11 Return pipe, 12 Small water pump, 13 Second temperature detector, 14 Drain pipe, 15 Air outlet pipe, 16 Heat dissipation fins, 17 Support connecting plate. Detailed Implementation

[0022] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that the description of this disclosure will be more complete and fully convey the concept of the exemplary embodiments to those skilled in the art. The drawings are merely illustrative of this disclosure and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted.

[0023] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more exemplary embodiments. Numerous specific details are provided in the following description to give a full understanding of exemplary embodiments of this disclosure. However, those skilled in the art will recognize that the technical solutions of this disclosure can be practiced with one or more of the specific details omitted, or other methods, components, steps, etc., can be employed. In other instances, well-known structures, methods, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this disclosure.

[0024] This utility model provides a device for preventing low-temperature corrosion of tubular air preheaters, such as... Figure 1 As shown, it includes an air preheater body 1, with water storage tanks 2 on both ends of the air preheater body 1. Multiple first temperature detectors 6 are provided in the middle of the upper end of the air preheater body 1, which can detect the water temperature inside the air preheater body 1 in real time through multiple first temperature detectors 6.

[0025] The upper end of the water storage tank 2 is provided with multiple return water pipes 9, and the lower end of the air preheater body 1 is provided with two bottom supports 3, which can support the air preheater body 1. One end of the air preheater body 1 is equipped with an air inlet hood 4, and the middle of the outer end of the air inlet hood 4 is provided with an air inlet pipe 5.

[0026] The air preheater body 1 has an air outlet hood 7 on the outside of the end away from the air inlet hood 4. Multiple air guide pipes 10 are provided at the connection between the air preheater body 1 and the air outlet hood 7. The air guide pipes 10 penetrate the end face of the air preheater body 1. The operator can guide the exhaust gas generated by the boiler into the interior of the air preheater body 1 from the air inlet pipe 5 and let it flow inside the air preheater body 1 through the multiple air guide pipes 10. A water supply pipe 8 is provided on one side of the upper end of the air preheater body 1, which can replenish the interior of the air preheater body 1 with hot water.

[0027] like Figure 2 , 3 As shown in Figure 4, the lower end of the water storage tank 2 is provided with multiple second temperature detectors 13 and multiple return pipes 11, which can detect the water temperature inside the water storage tank 2 through the second temperature detectors 13. The outer end face of the water storage tank 2 is provided with multiple heat dissipation fins 16, which can cool the heat exchange medium inside the water outlet tank 2 through the heat dissipation fins 16.

[0028] The outer end face of the return pipe 11 is equipped with a small water pump 12. The staff can drive the small water pump 12 to work through the external control equipment. The small water pump 12 will pour the clean water inside the 2 water storage tanks into the air preheater body 1 through the return pipe 11.

[0029] The water storage tank 2 is connected to the air preheater body 1 by a number of supporting connecting plates 17. The outer end face of the air outlet hood 7 is provided with a number of air outlet pipes 15. The gas inside the air guide pipe 10 will be re-collected inside the air outlet hood 7 and guided to the outside from the air outlet pipe 15.

[0030] The air preheater body 1 is provided with a drain pipe 14 at the middle of its lower end, which can discharge the heat exchange medium inside the air preheater body 1. The first temperature detector 6 and the second temperature detector 13 are both electrically connected to the external control equipment through wires. The first temperature detector 6 and the second temperature detector 13 are both commercially available MIK-WZP threaded resistance thermal sensors.

[0031] The air preheater body 1 and the water storage tank 2 are connected by a return pipe 11 and a return water pipe 9. The small water pumps 12 are electrically connected to the external control equipment through wires. When the boiler exhaust gas enters the interior of the air preheater body 1, it will cause the temperature of the heat exchange medium inside the air preheater body 1 to rise. After rising to a certain height, the heat exchange efficiency will decrease. The operator can drive the small water pumps 12 to work through the external control equipment. The small water pumps 12 will introduce water from the water storage tank 2 into the interior of the air preheater body 1.

[0032] Excess water inside the air preheater body 1 will enter the water storage tank 2 through the return water pipe 9, thereby cooling the heat exchange medium inside the air preheater body 1. At the same time, the first temperature detector 6 will detect the temperature of the heat exchange medium inside the air preheater body 1, so as to maintain the heat exchange medium inside the air preheater body 1 at a suitable temperature. After reaching a certain temperature, the small water pump 12 will stop working, thereby preventing the exhaust gas discharged from the boiler from directly contacting the cool air duct 10 and directly condensing into liquid acid, which would cause corrosion to the air duct 10.

[0033] Finally, it should be noted that: the accompanying drawings of the embodiments disclosed in this utility model only involve the structures involved in the embodiments disclosed in this utility model. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this utility model can be combined with each other.

[0034] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A device for preventing low-temperature corrosion of a tubular air preheater, comprising an air preheater body (1), characterized in that: The air preheater body (1) is provided with water storage tanks (2) on both sides of the end face. The upper middle part of the air preheater body (1) is provided with multiple first temperature detectors (6). The lower end of the water storage tank (2) is provided with multiple second temperature detectors (13) and multiple return pipes (11). The upper end of the water storage tank (2) is provided with multiple return water pipes (9), the outer end face of the water storage tank (2) is provided with multiple heat dissipation fins (16), and the outer end face of the return pipe (11) is provided with a small water pump (12).

2. The device for preventing low-temperature corrosion of a tubular air preheater according to claim 1, characterized in that: The lower end of the air preheater body (1) is provided with two bottom brackets (3), and the connection between the water storage tank (2) and the air preheater body (1) is provided with multiple supporting connecting plates (17).

3. The device for preventing low-temperature corrosion of a tubular air preheater according to claim 1, characterized in that: An air inlet hood (4) is installed at one end of the air preheater body (1), and an air inlet pipe (5) is provided in the middle of the outer end of the air inlet hood (4).

4. The device for preventing low-temperature corrosion of a tubular air preheater according to claim 3, characterized in that: The air preheater body (1) has an air outlet hood (7) on the outside of the end away from the air inlet hood (4), and the outer end face of the air outlet hood (7) is provided with multiple air outlet pipes (15).

5. The device for preventing low-temperature corrosion of a tubular air preheater according to claim 4, characterized in that: Multiple air guide pipes (10) are provided at the connection between the air preheater body (1) and the air outlet hood (7), and the air guide pipes (10) penetrate the end face of the air preheater body (1).

6. The device for preventing low-temperature corrosion of a tubular air preheater according to claim 1, characterized in that: A drain pipe (14) is provided in the middle of the lower end of the air preheater body (1), and a water supply pipe (8) is provided on one side of the upper end of the air preheater body (1).

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