A boiler wall-attached air blowing port device

Abstract

This application relates to the field of power plant boiler technology, specifically to a boiler wall-mounted air nozzle device. The boiler wall-mounted air nozzle device is used to control the flow trajectory of the wall-mounted air, so that the wall-mounted air forms an air film on the surface of the boiler water-cooled wall. The nozzle device includes a guide member with a flow channel. One end of the flow channel is connected to the wall-mounted air duct, and the other end bends and extends towards the center of the furnace. The flow channel is used to ensure that the wall-mounted air has a velocity component in the height direction and a velocity component in the depth direction of the furnace when it flows out. According to the above solution, the wall-mounted air can counteract the impact of the opposing combustion flue gas after entering the furnace, thereby forming an air film on the surface of the water-cooled wall and protecting the water-cooled wall. Furthermore, because the wall-mounted air has a velocity component in the height direction when it flows out of the flow channel, it can flow upward along the water-cooled wall, which increases the coverage area of ​​the wall-mounted air on the water-cooled wall, thereby improving the utilization efficiency of the wall-mounted air.

Description

Technical Field

[0001] This application relates to the field of power plant boiler technology, and more specifically, to a boiler wall-mounted air nozzle device. Background Technology

[0002] In recent years, coal-fired power plants have made significant progress in controlling ultra-low emissions of pollutants, with substantial improvements in pollutant control technologies. The vast majority of power plants have controlled NOx generation in the furnace through rich-lean combustion and staged air combustion, achieving ultra-low emissions. However, the contradiction between efficient combustion and low NOx emissions has become more prominent. Severe localized oxygen deficiency in the furnace, coupled with the use of high-sulfur coal, results in extremely high concentrations of CO and H2S in the localized atmosphere of the furnace water-cooled walls. This leads to widespread high-temperature corrosion of the water-cooled walls, causing frequent unit tube rupture accidents.

[0003] To mitigate high-temperature corrosion, some offset combustion boilers have adopted sidewall-mounted air technology. Theoretically, with sidewall-mounted air nozzles positioned on the sidewalls and the air sourced from secondary air ducts at each level, this directly increases the O2 concentration in the near-wall high-temperature corrosion zone while reducing CO and H2S content. Furthermore, the sidewall-mounted air only needs to flow upwards along the water-cooled wall, eliminating the need for high wind speeds and rigid airflow, thus perfectly solving the problem of traditional sidewall-mounted air systems failing to effectively protect the water-cooled walls due to insufficient rigidity. However, in practical applications, the sidewall-mounted air nozzles use simple rectangular or circular cross-sectional structures, resulting in flow fields such as… Figure 1 As shown, the wall-mounted air nozzle structure causes the wall-mounted air to enter the furnace perpendicular to the side wall direction, that is, the wall-mounted air flows towards the depth of the furnace. The protection range in the height direction is limited, and it is affected by the impact of the opposing combustion flue gas in the width direction. The wall-mounted air flows rapidly towards the front and rear walls, and the airflow of the wall-mounted air is difficult to form an air film in the near wall area of ​​the side wall, which greatly weakens the protection effect on the water-cooled side wall. Summary of the Invention

[0004] This application provides at least one boiler wall-mounted air nozzle device to improve the weak protection effect of wall-mounted air on the boiler side wall, thereby effectively alleviating the high-temperature corrosion problem of boiler water-cooled walls.

[0005] This application provides a boiler wall-mounted air nozzle device for controlling the flow trajectory of the wall-mounted air to form an air film on the surface of the boiler water-cooled wall. The nozzle device includes a flow guide with a flow channel. One end of the flow channel is connected to the wall-mounted air duct, and the other end bends and extends towards the center of the furnace. The flow channel is used to give the wall-mounted air a velocity component in the height direction and a velocity component in the depth direction of the furnace when it flows out.

[0006] In one alternative embodiment, the flow guide is a tubular structure, and the flow guide is partially twisted and / or bent so that the flow channel bends and extends toward the center of the furnace.

[0007] In one optional embodiment, the flow guide includes a first flow guide section, a second flow guide section, and a third flow guide section connected in sequence along the flow guide direction, wherein the second flow guide section is twisted and rotated along the flow guide direction, and there is an included angle between the second flow guide section and the third flow guide section.

[0008] In one optional embodiment, the air inlet end of the air guide is a flared structure, and the air inlet end of the air guide is arc-shaped on both sides along the width direction.

[0009] In one optional embodiment, the air inlet end of the air guide is provided with a plurality of first air guide plates, which are spaced apart along the width direction of the air inlet end of the air guide.

[0010] In one alternative implementation, the first guide plate is an arc-shaped plate.

[0011] In one alternative implementation, the first guide plate extends outward from the first guide section into the wall-mounted air duct.

[0012] In one optional embodiment, the air outlet end of the air guide is provided with a plurality of second air guide plates, which are spaced apart along the width direction of the air outlet end of the air guide.

[0013] In one optional embodiment, the angle between the air outlet direction and the height direction of the air guide is 45°~60°.

[0014] In one optional embodiment, the angle between the air outlet direction of the guide and the depth direction of the furnace is 45°~60°.

[0015] The above-mentioned technical solution of this application has the following beneficial technical effects:

[0016] The boiler wall-mounted air nozzle device of this application embodiment enables the wall-mounted air to counteract the impact of the opposing combustion flue gas after entering the furnace, thereby forming an air film on the surface of the water-cooled wall and protecting it. Furthermore, because the wall-mounted air has a velocity component in the height direction when flowing out of the flow channel, it can flow upwards along the water-cooled wall, increasing the coverage area of ​​the wall-mounted air and thus improving its utilization efficiency.

[0017] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly described below. These drawings are incorporated in and constitute a part of this specification. They illustrate embodiments conforming to this application and, together with the specification, serve to explain the technical solutions of this application. It should be understood that the following drawings only show some embodiments of this application and should not be considered as limiting the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This application illustrates a usage scenario of a boiler wall-mounted air nozzle device provided in an embodiment of this application;

[0020] Figure 2 This paper shows a schematic diagram of the structure of a boiler wall-mounted air nozzle device provided in an embodiment of this application;

[0021] Reference numerals in the attached drawings: 1. Wall-mounted air duct; 2. Air guide; 21. First air guide section; 22. Second air guide section; 23. Third air guide section; 24. First air guide plate; 25. Second air guide plate. Detailed Implementation

[0022] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0023] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0024] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0025] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0026] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0027] refer to Figure 1 This application provides a boiler wall-mounted air nozzle device. The nozzle device is installed at the wall-mounted air duct 1 and can control the flow trajectory of the wall-mounted air so that the wall-mounted air forms an air film on the surface of the boiler water-cooled wall.

[0028] refer to Figure 1 and Figure 2 In some embodiments, the nozzle device includes a guide member 2 with a flow channel. One end of the flow channel is connected to the wall-mounted air duct 1, and the other end bends and extends towards the center of the furnace. The flow channel is used to ensure that the wall-mounted air has a velocity component in the height direction and a velocity component in the furnace depth direction when it flows out. Specifically, the flow channel of the guide member 2 is connected to the wall-mounted air duct 1, allowing the wall-mounted air to flow into the furnace through the flow channel. Furthermore, because the flow channel bends and extends towards the center of the furnace, the wall-mounted air has a velocity component in the height direction and a velocity component in the furnace depth direction when it flows out of the flow channel. The height direction velocity component refers to the wall-mounted air flowing upwards along the water-cooled wall when it flows out of the flow channel, while the furnace depth direction velocity component refers to the wall-mounted air flowing towards the center of the furnace when it flows out of the flow channel. This configuration allows the wall-mounted air to counteract the impact of the opposing combustion flue gas after entering the furnace, thereby forming a gas film on the surface of the water-cooled wall and protecting it. Furthermore, since the wall-mounted air can flow upward along the water-cooled wall when it flows out of the flow channel, this can increase the coverage area of ​​the wall-mounted air on the water-cooled wall, thereby improving the utilization efficiency of the wall-mounted air.

[0029] In some embodiments, the angle between the air outlet direction of the air outlet end of the guide member 2 and the height direction is 45°~60°, and the angle between the air outlet direction of the air outlet end of the guide member 2 and the depth direction of the furnace is 45°~60°. However, the embodiments of this application do not impose any limitations on this.

[0030] In some embodiments, the flow guide 2 is a tubular structure. For example, the flow guide 2 can be a rectangular tubular structure, a circular tubular structure, etc. In this embodiment, the flow guide 2 is preferably a Q355 or 310S rectangular tubular structure. However, this application embodiment does not limit this in any way.

[0031] In some embodiments, the flow guide 2 is partially twisted and / or bent to cause the flow channel to bend and extend towards the center of the furnace. In this embodiment, the flow guide 2 can simultaneously employ twisting and bending to enable the flow channel to bend and extend towards the center of the furnace. For example, the flow guide 2 includes a first flow guide section 21, a second flow guide section 22, and a third flow guide section 23 connected sequentially along the flow guide direction, wherein the second flow guide section 22 is twisted and rotated along the flow guide direction, and there is an angle between the second flow guide section 22 and the third flow guide section 23. That is, the flow guide 2 is twisted in the second flow guide section 22 and bent between the second flow guide section 22 and the third flow guide section 23, thereby causing the flow channel to bend and extend towards the center of the furnace. However, the embodiments of this application do not limit this in any way.

[0032] In some embodiments, the first guide section 21 and the third guide section 23 are straight pipe sections. This configuration ensures a relatively uniform velocity distribution of the airflow along the wall in the first guide section 21 and the third guide section 23, thereby avoiding the presence of localized low-velocity zones within the nozzle, which could lead to problems such as dust accumulation and burn-out. However, this application embodiment does not impose any limitations on this.

[0033] In some embodiments, the air inlet end of the guide member 2 (i.e., the first guide section 21) is a flared structure, and the two sides of the air inlet end of the guide member 2 along the width direction are arc-shaped. This configuration can guide the airflow to a smooth transition, reduce airflow turbulence and vortices, and the arc-shaped wall can change the airflow path, making the airflow evenly distributed before entering the nozzle. At the same time, the arc-shaped wall can reduce airflow resistance and increase airflow velocity and flow rate. However, the embodiments of this application do not impose any limitations on this.

[0034] In some embodiments, the air inlet end of the guide member 2 is provided with a plurality of first guide plates 24, which are spaced apart along the width direction of the air inlet end of the guide member 2. Specifically, the first guide plates 24 are located near the windward side and are arc-shaped plates. This arrangement can change the airflow path, making the airflow evenly distributed before entering the nozzle, while reducing eddies and vortices in the airflow and improving the stability of the airflow. However, the embodiments of this application do not limit this in any way.

[0035] In some embodiments, the first guide plate 24 extends outward from the first guide section 21 into the wall-mounted air duct 1. Depending on the actual high-temperature corrosion conditions, the airflow entering the nozzle can be changed and the wall-mounted airflow distribution optimized by adjusting the length of the first guide plate 24 extending into the wall-mounted air duct 1. In specific configurations, the lengths of each first guide plate 24 extending into the wall-mounted air duct 1 can be the same or different. However, this application embodiment does not impose any limitation on this.

[0036] In some embodiments, the air outlet end of the guide member 2 is provided with a plurality of second guide plates 25, which are spaced apart along the width direction of the air outlet end of the guide member 2. Specifically, the second guide plates 25 are located in the third guide section 23, and the second guide plates 25 are flat plates. This arrangement enables the airflow to be evenly distributed in the air outlet area, thereby ensuring uniform airflow distribution when entering the furnace. Moreover, the second guide plates 25 reduce eddies and vortices in the airflow, improving the stability of the airflow. However, the embodiments of this application do not impose any limitations on this.

[0037] The boiler wall-mounted air nozzle device of this application embodiment enables the wall-mounted air to counteract the impact of the opposing combustion flue gas after entering the furnace, thereby forming an air film on the surface of the water-cooled wall and protecting it. Furthermore, because the wall-mounted air has a velocity component in the height direction when flowing out of the flow channel, it can flow upwards along the water-cooled wall, increasing the coverage area of ​​the wall-mounted air and thus improving its utilization efficiency.

[0038] One or more embodiments in this specification are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments in this specification should be included within the protection scope of this application.

[0039] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A boiler wall-mounted air nozzle device for controlling the flow trajectory of the wall-mounted air to form an air film on the surface of the boiler water-cooled wall, characterized in that, The nozzle device includes a flow guide with a flow channel. One end of the flow channel is connected to the wall-mounted air duct, and the other end bends and extends towards the center of the furnace. The flow channel is used to give the wall-mounted air a velocity component in the height direction and a velocity component in the furnace depth direction when it flows out. The flow guide includes a first flow guide section, a second flow guide section, and a third flow guide section connected in sequence along the flow guide direction. The second flow guide section is twisted and rotated along the flow guide direction, and there is an angle between the second flow guide section and the third flow guide section. The angle between the air outlet direction of the flow guide and the height direction is 45°~60°. The angle between the air outlet direction of the flow guide and the furnace depth direction is 45°~60°.

2. The boiler wall-mounted air nozzle device according to claim 1, characterized in that, The air inlet of the air guide is a flared structure, and the air inlet of the air guide is arc-shaped on both sides along the width direction.

3. The boiler wall-mounted air nozzle device according to claim 1, characterized in that, The air inlet end of the air guide is provided with a plurality of first air guide plates, which are spaced apart along the width direction of the air inlet end of the air guide.

4. The boiler wall-mounted air nozzle device according to claim 3, characterized in that, The first guide plate is an arc-shaped plate.

5. The boiler wall-mounted air nozzle device according to claim 3, characterized in that, The first guide plate extends outward from the first guide section into the wall-mounted air duct.

6. The boiler wall-mounted air nozzle device according to claim 1, characterized in that, The air outlet end of the air guide is provided with a plurality of second air guide plates, which are spaced apart along the width direction of the air outlet end of the air guide.

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