Steam air heater, boiler air supply system and thermal power generation system
By setting a first drain pipe and an automatic trap in the steam air heater, the steam condensate in the inlet and outlet box is discharged, which solves the problem of steam leakage easily caused by cracks in the steam air heater, and improves the stability and safety of the equipment.
Patent Information
- Application Number
- CN202421576021.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-04
- Publication Date
- 2025-06-17
- Estimated Expiration
- 2034-07-04
AI Technical Summary
Existing steam air heaters are prone to cracks and lead to steam leakage when used.
A steam air heater is designed, including a air heater body, a first drain pipe and an automatic trap. The air heater body consists of an inlet connection box, an outlet connection box and a plurality of heat exchange pipes. The first drain pipe is arranged below the air heater body and is in communication with the inlet connection box. The automatic trap is connected to the end of the first drain pipe to discharge the steam condensate in the inlet connection box.
By reducing the amount of steam condensation water in the inlet box, the impact of the gas-liquid mixture on the inlet box is reduced, and the risk of cracks and the occurrence of steam leakage is reduced.
Smart Images
Figure CN222992937U_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to the technical field of steam air heaters, and particularly to a steam air heater, a boiler air supply system, and a thermal power generation system. Background Art
[0002] The oxygen required by the combustion chamber of a thermal power plant is extracted from the natural environment. The air extracted by the air blower first passes through an air preheater in the air duct and is heated to about 300 degrees Celsius before being transported to the boiler combustion chamber to improve the combustion efficiency. In winter, due to the low ambient temperature, the temperature of the air transported by the air blower is too low. If the cold air directly enters the air preheater, it will cause low-temperature corrosion at the cold end of the air preheater (sulfur in the flue gas condenses with the cold air to produce sulfuric acid). Therefore, a steam air heater is usually installed in the air duct before the air preheater to preheat the cold air in the air duct, and the steam of the steam air heater is provided by an auxiliary steam header.
[0003] However, the existing steam air heaters are prone to cracks during use, resulting in steam leakage. Summary of the Utility Model
[0004] The purpose of the present disclosure is to provide a steam air heater, a boiler air supply system, and a thermal power generation system to solve the technical problems existing in the related art.
[0005] To achieve the above purpose, the present disclosure provides a steam air heater, including a heater body, a first drain pipe, and an automatic drain valve. The heater body includes an inlet header, an outlet header, and a plurality of heat exchange tubes connecting the inlet header and the outlet header. The inlet header has a steam inlet for connecting to a steam main pipe, and the outlet header has a steam outlet for connecting to a drain main pipe. The first drain pipe is arranged below the heater body, and the first end of the first drain pipe is connected to the inlet header, and the connection position of the first end of the first drain pipe to the inlet header is lower than the connection position of any of the heat exchange tubes to the inlet header. The inlet of the automatic drain valve is connected to the second end of the first drain pipe.
[0006] Optionally, the connection position of the first drain pipe to the inlet header is located at the lowest point of the inlet header.
[0007] Optionally, the steam air heater further includes a second drain pipe. The first end of the second drain pipe is connected to the outlet of the automatic drain valve, and the second end of the second drain pipe is connected to the outlet header.
[0008] Optionally, the connection position of the second end of the second drain pipe to the outlet header is lower than the connection position of any of the heat exchange tubes to the outlet header.
[0009] Optionally, the steam air heater further includes a first switching valve. The inlet of the first switching valve is used to connect to the steam main pipe, and the outlet of the first switching valve is connected to the steam inlet.
[0010] Optionally, the steam air heater further includes a second switching valve. The inlet of the second switching valve is connected to the steam outlet, and the outlet of the second switching valve is used to connect to the drain main pipe.
[0011] Optionally, both the first switching valve and the second switching valve are manual switching valves.
[0012] In a second aspect of the present disclosure, there is provided a boiler gas supply system. The boiler gas supply system includes an air duct, a steam main pipe, a drain main pipe, and the above-mentioned steam air heater. The heater body of the steam air heater is disposed in the air duct.
[0013] Optionally, there are multiple steam air heaters. The boiler gas supply system further includes a shunt pipe and a confluence pipe. The steam main pipe is connected to the steam inlets of the inlet headers of the multiple steam air heaters through the shunt pipe, and the drain main pipe is connected to the steam outlets of the outlet headers of the multiple steam air heaters through the confluence pipe.
[0014] In a third aspect of the present disclosure, there is provided a thermal power generation system. The thermal power generation system includes the above-mentioned boiler gas supply system.
[0015] Through the above solution, a first drain pipe is provided below the heater body of the air heater, and the first end of the first drain pipe is communicated with the inlet header, so that the steam condensate in the steam-water mixture generated in the inlet header can flow into the first drain pipe under the action of gravity and is discharged outside the steam air heater through an automatic drain valve connected to the second end of the first drain pipe. Moreover, since the connection position of the first section of the first drain pipe and the inlet header is lower than the connection position of any heat exchange pipe and the inlet header, the amount of steam condensate accumulated in the inlet header can be reduced. Therefore, the "pipe hitting" phenomenon generated by the gas-liquid mixture during the flow in the inlet header can be reduced, and further the risk of steam leakage caused by cracks in the inlet header can be reduced.
[0016] Other features and advantages of the present disclosure will be described in detail in the subsequent specific implementation part. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. They are used to explain the present disclosure together with the following specific implementation manners, but do not constitute a limitation to the present disclosure. In the drawings:
[0018] Figure 1It is a schematic diagram showing the connection of multiple steam warm air heaters to a steam main pipe and a drain main pipe provided by an exemplary embodiment of the present disclosure.
[0019] Explanation of Reference Numerals
[0020] 10 - Steam main pipe; 20 - Drain main pipe;
[0021] 100 - Warm air heater body; 110 - Inlet header; 120 - Heat exchange tubes; 130 - Outlet header;
[0022] 200 - First drain pipe;
[0023] 300 - Automatic drain valve;
[0024] 400 - Second drain pipe;
[0025] 500 - Shunt pipe;
[0026] 600 - Confluence pipe
[0027] 700 - First on-off valve;
[0028] 800 - Second on-off valve. Detailed Embodiment
[0029] The following will describe the detailed embodiment of the present disclosure with reference to the accompanying drawings. It should be understood that the specific embodiment described herein is only for the purpose of illustrating and explaining the present disclosure, and is not used to limit the present disclosure.
[0030] In the description of the present disclosure, it should be understood that the terms "inside, outside" refer to the inside and outside of the corresponding structural contour. In addition, the terms "first", "second", etc. are only used to distinguish one element from another, and do not have sequentiality and importance.
[0031] In the description of the present disclosure, it should also be noted that unless otherwise clearly specified and limited, the terms "set", "connected", "coupled", "installed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present disclosure can be understood according to specific situations.
[0032] The inventors of the present disclosure have found through research that when the steam inlet flow rate is low, the steam in the inlet header of the steam air heater expands and does work, and at the same time, it is rapidly cooled by the cold air in the air duct, resulting in a temperature drop and the formation of steam condensate. The steam condensate mixes with the steam in the inlet header to form a steam-water mixture. During the flow of the steam-water mixture, the steam condensate in the steam-water mixture will cause a "pipe collision" phenomenon with the inlet header, resulting in severe vibration of the inlet header of the air heater. After long-term operation, cracks occur at the inlet header, leading to steam leakage.
[0033] In view of this, the present disclosure provides a steam air heater in the first aspect to solve the technical problem that the existing steam air heater is prone to cracks and steam leakage during use.
[0034] As Figure 1 shown, the steam air heater provided by the present disclosure includes a heater body 100, a first drain pipe 200, and an automatic drain valve 300. The heater body 100 includes an inlet header 110, an outlet header 130, and a plurality of heat exchange tubes 120 connecting the inlet header 110 and the outlet header 130. The inlet header 110 has a steam inlet for connecting to a steam main pipe 10, and the outlet header 130 has a steam outlet for connecting to a drain main pipe 20. The first drain pipe 200 is disposed below the heater body 100. The first end of the first drain pipe 200 is connected to the inlet header 110, and the connection position of the first end of the first drain pipe 200 to the inlet header 110 is lower than the connection position of any heat exchange tube 120 to the inlet header 110. The inlet of the automatic drain valve 300 is connected to the second end of the first drain pipe 200.
[0035] Through the above technical solution, a first drain pipe 200 is disposed below the heater body 100, and the first end of the first drain pipe 200 is connected to the inlet header 110, so that the steam condensate in the steam-water mixture generated in the inlet header 110 can flow into the first drain pipe 200 under the action of gravity and be discharged outside the steam air heater through the automatic drain valve 300 connected to the second end of the first drain pipe 200. Moreover, since the connection position of the first section of the first drain pipe 200 to the inlet header 110 is lower than the connection position of any heat exchange tube 120 to the inlet header 110, the amount of steam condensate accumulated in the inlet header 110 can be reduced. Therefore, the "pipe collision" phenomenon generated by the gas-liquid mixture during the flow in the inlet header 110 is reduced, and further, the risk of cracks occurring in the inlet header 110 and resulting in steam leakage is reduced.
[0036] It should be noted that the above-mentioned automatic steam trap is also called an automatic drainer or condensate discharger. The steam trap can automatically identify steam and water (excluding thermostatic types), thereby achieving the purpose of automatically blocking steam and draining water. According to different operating principles, automatic steam traps can include mechanical steam traps, thermostatic steam traps, and thermodynamic steam traps. Mechanical steam traps utilize the density difference between condensate and steam. Through the change in the condensate level, the float rises and falls to drive the valve flap to open or close, achieving the purpose of blocking steam and draining water. Thermostatic steam traps are provided with a temperature-sensitive element or liquid inside. Utilizing the gradually increasing temperature of the condensate acting on the temperature-sensitive element or liquid, the temperature-sensitive element or liquid drives the valve core to open or close, achieving the purpose of blocking steam and draining water. Thermodynamic steam traps use the steam in the pipeline itself to heat-insulate the main steam chamber of the steam trap, making the temperature of the main steam chamber not easy to drop, maintaining the steam pressure, and the steam trap tightly closes; when condensate is generated in the pipeline, the outer shell of the steam trap cools down, and the steam trap starts to drain water; if no condensate is generated in the pipeline, the steam trap will not open, achieving the purpose of blocking steam and draining water.
[0037] Optionally, the above-mentioned automatic steam trap of the present disclosure can be a mechanical steam trap, a thermostatic steam trap, or a thermodynamic steam trap, and the present disclosure does not limit this.
[0038] In some alternative embodiments, the connection position of the first drain pipe 200 and the inlet header 110 is located at the lowest point of the inlet header 110. The steam condensate generated in the inlet header 110 can flow more into the first drain pipe 200 and be discharged from the automatic steam trap 300.
[0039] In some alternative embodiments, the steam air heater further includes a second drain pipe 400. The first end of the second drain pipe 400 is connected to the outlet of the automatic steam trap 300, and the second end of the second drain pipe 400 is connected to the outlet header 130. The steam condensate flowing into the first drain pipe 200 will pass through the automatic steam trap 300 and the second drain pipe 400 and enter the outlet header 130, and then enter the drain main pipe 20 from the outlet header 130, and finally enter the drain tank of the boiler, realizing the recycling of steam condensate.
[0040] In some alternative embodiments, the connection position of the second end of the second drain pipe 400 and the outlet header 130 is lower than the connection position of any heat exchange pipe 120 and the outlet header 130. To prevent the steam condensate from splashing when flowing into the outlet header 130.
[0041] In some alternative embodiments, the steam air heater further includes a first switching valve 700. The inlet of the first switching valve 700 is used to connect to the steam main pipe 10, and the outlet of the first switching valve 700 is connected to the steam inlet.
[0042] A first switching valve 700 is provided, which can control the amount of steam (i.e., the steam inlet flow rate) entering the inlet header 110 from the inlet main pipe by adjusting the opening degree of the first switching valve 700, and can adjust the heat exchange efficiency of the steam air heater. Moreover, when there are multiple heater bodies 100 and the steam inlet flow rate is relatively low, the first switching valve 700 connected to some of the heater bodies 100 can be closed, so that the steam inlet flow rate of the remaining heater bodies 100 increases, thereby reducing the "pipe collision" phenomenon in the inlet header 110 of the heater body 100.
[0043] In some alternative embodiments, the steam air heater further includes a second switching valve 800. The inlet of the second switching valve 800 is connected to the steam outlet, and the outlet of the second switching valve 800 is used to be connected to the drain main pipe 20.
[0044] By providing the second switching valve 800, the flow rate of steam entering the drain main pipe 20 from the outlet header 130 can be controlled by adjusting the opening degree of the second switching valve 800, and in cooperation with the first switching valve 700, the control of the steam inlet flow rate can be achieved. Moreover, after completely closing the first switching valve 700 and the second switching valve 800, steam can also be prevented from entering the corresponding heater body 100.
[0045] In some alternative embodiments, both the first switching valve 700 and the second switching valve 800 are manual switching valves. The operator can manually control the opening degrees of the first switching valve 700 and the second switching valve 800 according to the usage requirements. Of course, in other embodiments, the first switching valve 700 and the second switching valve 800 can also be automatic valves, and the controller controls the opening degrees of the first switching valve 700 and the second switching valve 800.
[0046] Based on the above steam air heater, the present disclosure provides a boiler air supply system in a second aspect. The boiler air supply system includes an air duct, a steam main pipe 10, a drain main pipe 20, and the above steam air heater. The heater body 100 of the steam air heater is arranged in the air duct to exchange heat with the air flow in the air duct and heat the air flow in the air duct.
[0047] In some alternative embodiments, there are multiple steam air heaters. The boiler air supply system further includes a shunt pipe 500 and a confluence pipe 600. The steam main pipe 10 is connected to the steam inlets of the inlet headers 110 of the multiple steam air heaters through the shunt pipe 500, and the drain main pipe 20 is connected to the steam outlets of the outlet headers 130 of the multiple steam air heaters through the confluence pipe 600.
[0048] Multiple heater bodies 100 can improve the heating effect on the air in the air duct. At the same time, when the steam flow rate is low, some of the heater bodies 100 can be selected to be closed so that the steam flow rate in the remaining unclosed heater bodies 100 meets the usage requirements, thereby reducing the technical problems that the inlet header 110 of the steam heater warms up slowly due to low steam flow rate and further generating more steam condensate water.
[0049] Optionally, the first switching valve 700 and the second switching valve 800 are located outside the air duct, so that the operator can more conveniently control the opening degrees of the first switching valve 700 and the second switching valve 800.
[0050] The present disclosure provides a thermal power generation system in a third aspect, and the thermal power generation system includes the above-mentioned boiler air supply system.
[0051] The preferred embodiments of the present disclosure have been described in detail above in conjunction with the accompanying drawings. However, the present disclosure is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.
[0052] In addition, it should be noted that, among the various specific technical features described in the above specific embodiments, they can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present disclosure does not separately describe various possible combination methods.
[0053] Furthermore, any combination can be made between various different embodiments of the present disclosure as long as it does not violate the idea of the present disclosure, and it should also be regarded as the content disclosed by the present disclosure.
Claims
1. A steam heater, characterized in that: include: The heater body comprises an inlet header, an outlet header and a plurality of heat exchange tubes connecting the inlet header and the outlet header, the inlet header has a steam inlet for connecting to a steam main pipe, and the outlet header has a steam outlet for connecting to a drain main pipe; A first drain pipe is disposed below the heater body, wherein a first end of the first drain pipe is connected to the inlet header, and a connection position between the first end of the first drain pipe and the inlet header is lower than a connection position between any of the heat exchange pipes and the inlet header; An automatic drain valve, wherein the inlet of the automatic drain valve is connected to the second end of the first drain pipe.
2. The steam air heater according to claim 1, characterized in that: The communication position between the first drain pipe and the inlet header is located at the lowest point of the inlet header.
3. The steam air heater according to claim 1, characterized in that: The steam air heater further comprises a second drain pipe, a first end of which is connected to the outlet of the automatic drain valve, and a second end of which is communicated with the outlet manifold.
4. The steam air heater according to claim 3, characterized in that: The communication position between the second end of the second drain pipe and the outlet header is lower than the communication position between any of the heat exchange pipes and the outlet header.
5. The steam air heater according to claim 1, characterized in that: The steam air heater further comprises a first switch valve, an inlet of the first switch valve is used to be connected to the steam main pipe, and an outlet of the first switch valve is connected to the steam inlet.
6. The steam air heater according to claim 5, characterized in that: The steam air heater further comprises a second switch valve, an inlet of the second switch valve is connected to the steam outlet, and an outlet of the second switch valve is used to be connected to the drain main pipe.
7. The steam air heater according to claim 6, characterized in that: The first switch valve and the second switch valve are both manual switch valves.
8. A boiler gas supply system, characterized in that: The invention comprises an air duct, a steam main pipe, a drain main pipe and a steam air heater as described in any one of claims 1 to 7, wherein the heater body of the steam air heater is arranged in the air duct.
9. The boiler gas supply system according to claim 8, characterized in that: There are multiple steam air heaters, and the boiler air supply system also includes a shunt pipe and a manifold. The steam main pipe is connected to the steam inlets of the inlet manifolds of the multiple steam air heaters via the shunt pipe, and the drain main pipe is connected to the steam outlets of the outlet manifolds of the multiple steam air heaters via the manifold.
10. A thermal power generation system, characterized in that: Includes the boiler gas supply system as claimed in claim 9.