A water-cooled wall pipe, a water-cooled wall device and a boiler

Abstract

The present invention provides a water wall pipe, a water wall device and a boiler. The water wall pipe includes a pipe body, and the pipe body is adapted to be disposed outside an opening where a bypass pipe communicates with the boiler; the cross-sectional shape of the pipe body is a first shape. After installation, the length of the first shape parallel to the flue gas flow direction is a first length, and the length perpendicular to the flue gas flow direction is a second length, and the first length is greater than the second length; the cross-sectional area of the pipe body is the same as that of the adjacent circular water wall pipes above and below. For the water wall pipe with this structure, the length of the pipe body parallel to the flue gas flow direction is elongated, and the length of the pipe body perpendicular to the flue gas flow direction is shortened, that is, the cross-section of the pipe body is made into a flat and long shape. The width of the first shape perpendicular to the flue gas flow direction is narrower than that of the circular cross-section, increasing the gap between the pipes and the effective area through which the flue gas can pass, reducing the resistance of the flue gas passing through, and being beneficial to reducing the resistance and energy consumption of the boiler system.

Description

Technical Field

[0001] The present invention relates to the technical field of boiler heat dissipation, and particularly relates to a water wall pipe, a water wall device and a boiler. Background Art

[0002] In the existing technology, for a retrofitted or newly built denitration reactor, a bypass flue is added to the side wall of the boiler at the front end of the denitration reactor. Part of the high-temperature flue gas in the boiler is led out of the boiler through a bypass pipe to ensure that the temperature of the flue gas entering the denitration reactor is within the designed range, so as to ensure the denitration efficiency. An opening communicating with the bypass pipe is provided on the side wall of the boiler, and the high-temperature flue gas enters the bypass pipe through this opening and is discharged from the boiler. A large number of vertically arranged water wall pipes are arranged outside the opening. The multiple water wall pipes are arranged in parallel at intervals. The high-temperature flue gas in the furnace can only enter the bypass flue through the gaps between the water wall pipes.

[0003] To ensure the flow rate of the water wall pipes, the existing water wall pipes are made of circular steel pipes and are connected by headers. The cross-section of the water wall pipe is circular. The projection width of the circular cross-section on the opening is its diameter size. The width of the pipe in the direction perpendicular to the flue gas flow direction is relatively wide, the distance between adjacent pipes becomes smaller, and the gap through which the flue gas can pass becomes narrower. The projection area of the water wall pipe on the opening almost occupies half of the entire opening area, and the effective cross-section through which the flue gas can pass is very small, greatly increasing the resistance of the flue gas passing through, as well as the resistance and energy consumption of the system. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defect that the width of the circular water wall pipe outside the opening where the bypass pipe communicates with the boiler in the direction perpendicular to the flue gas flow direction is relatively wide, resulting in an increase in the resistance of the flue gas passing through.

[0005] For this purpose, the present invention provides a water wall pipe, including

[0006] A pipe body, which is adapted to be arranged outside the opening where the bypass pipe communicates with the boiler; the cross-sectional shape of the pipe body is a first shape, the length of the first shape parallel to the flue gas flow direction is a first length, and the length perpendicular to the flue gas flow direction is a second length, and the first length is greater than the second length;

[0007] The cross-sectional area of the pipe body is the same as that of the adjacent circular water wall pipes above and below it.

[0008] Optionally, for the above water wall pipe, the surface of the pipe body facing the opening is an arc surface.

[0009] Optionally, for the above water wall pipe, the first shape is a spindle shape.

[0010] Optionally, for the above-mentioned water-cooled wall pipes, the first shape is an ellipse.

[0011] Optionally, for the above-mentioned water-cooled wall pipes, the first shape is a water droplet shape.

[0012] Optionally, for the above-mentioned water-cooled wall pipes, for the water droplet shape, the side with a narrower width is the first side, and the side with a wider width is the second side. After the pipe body is installed, the first side faces the opening.

[0013] Optionally, for the above-mentioned water-cooled wall pipes, the ratio of the first length to the second length is 2 - 30.

[0014] Optionally, for the above-mentioned water-cooled wall pipes, the ratio of the first length to the second length is 2 - 3.

[0015] The present invention provides a water-cooled wall device, including the water-cooled wall pipes and headers described in any one of the above. A plurality of the water-cooled wall pipes are arranged in parallel at intervals, and their upper and lower ends are respectively communicated with the headers.

[0016] The present invention provides a boiler, including the above-mentioned water-cooled wall device.

[0017] The technical solution of the present invention has the following advantages:

[0018] 1. For the water-cooled wall pipes provided by the present invention, during use, they are installed between two headers outside the opening on the side wall of the boiler that is communicated with the bypass pipe. To ensure that the flow rate of the water-cooled wall pipes remains unchanged compared to circular water-cooled wall pipes, the cross-sectional area of the pipe body is made the same as that of the circular water-cooled wall pipes adjacent to the upper and lower sides of the header, the length of the pipe body parallel to the flue gas flow direction is elongated, and the length of the pipe body perpendicular to the flue gas flow direction is shortened, that is, the cross-section of the pipe body is made into a flat and long shape. The width of the first shape along the direction perpendicular to the flue gas flow is narrower than that of the circular cross-section, increasing the gap between the pipes and the effective area through which the flue gas can pass, reducing the resistance to the passage of the flue gas, and being beneficial to reducing the resistance and energy consumption of the boiler system.

[0019] 2. For the water-cooled wall device provided by the present invention, after being installed on the outer wall of the boiler, the gap between the water-cooled wall pipes is large, and the resistance of the flue gas passing through the water-cooled wall pipes through the boiler opening is small.

[0020] 3. For the boiler provided by the present invention, which includes a water-cooled wall device, the resistance of the flue gas passing through the bypass pipe is small, and the boiler system has low resistance and energy saving. Description of the Drawings

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0022] Figure 1 Schematic diagram of the water-cooled wall device provided for Embodiment 2 of the present invention;

[0023] Figure 2 For Figure 1 Cross-sectional view of the water-cooled wall pipes in the direction of the flue gas flow;

[0024] Figure 3 For Figure 1 Cross-sectional view of the water-cooled wall pipes in the direction of the flue gas flow;

[0025] Figure 4 For Figure 1 Cross-sectional view of the water-cooled wall pipes in the direction of the flue gas flow.

[0026] Explanation of reference numerals:

[0027] 11 - Diverting pipe; 12 - Vertical pipe; 13 - First elbow joint; 14 - Second elbow joint; 15 - First side; 16 - Second side; 21 - Header. Specific embodiments

[0028] The following will clearly and completely describe the technical solutions of the present invention with reference to the drawings. Obviously, the described embodiments are some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0029] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation of the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0030] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" 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 a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0032] Embodiment 1

[0033] This embodiment provides a water wall pipe, as Figures 2 to 4 shown, which includes a pipe body. The pipe body is adapted to be disposed outside the opening where the bypass pipe communicates with the boiler; the cross-sectional shape of the pipe body is a first shape. After installation, the length of the first shape parallel to the flue gas flow direction is a first length, and the length perpendicular to the flue gas flow direction is a second length, and the first length is greater than the second length; the cross-sectional area of the pipe body is the same as that of the circular water wall pipes adjacent to it above and below.

[0034] The normal water wall pipes are arranged vertically along the outer wall of the boiler, and multiple water wall pipes at a certain height interval are connected by headers 21. When this structure of the water wall pipe is in use, it is installed between two headers 21 outside the opening where the side wall of the boiler communicates with the bypass pipe. To ensure that the flow rate of the water wall pipe is the same as that of the circular water wall pipe, the cross-sectional area of the pipe body is made the same as that of the circular water wall pipes adjacent to the upper and lower sides of the header 21, the length of the pipe body parallel to the flue gas flow direction is lengthened, and the length of the pipe body perpendicular to the flue gas flow direction is shortened, that is, the cross-section of the pipe body is made into a flat and long shape. The width of the first shape perpendicular to the flue gas flow direction is narrower than that of the circular cross-section, increasing the gap between the pipes and the effective area through which the flue gas can pass, reducing the resistance of the flue gas passing through, and facilitating the reduction of the resistance and energy consumption of the boiler system.

[0035] Preferably, the surface of the pipe body facing the opening is an arc surface, and the windward surface of the pipe body is an arc surface, which is conducive to guiding the flue gas, with a good flow field and small resistance to the passing of the flue gas, and less wear on the windward surface of the pipe compared to the outer wall surface with edges and corners.

[0036] For example, referring to Figure 3 , the first shape is an ellipse, the long axis of the ellipse is parallel to the flue gas flow direction, the short axis is perpendicular to the flue gas flow direction, the short axis is narrow, and the gap between the pipes is large.

[0037] Or, referring to Figure 2, the first shape is fusiform, and the line connecting the two endpoints parallel to the flue gas flow direction is used as its major axis, and the line connecting the two endpoints perpendicular to the flue gas flow direction is used as its minor axis.

[0038] See Figure 4 , the first shape can also be a water droplet shape, and the line connecting the two end faces parallel to the flue gas flow direction is used as its major axis, and the line connecting the two endpoints perpendicular to the flue gas flow direction is used as its minor axis. The narrower side of the water droplet shape is the first side 15, and the wider side is the second side 16, that is Figure 4 In, the upper side of the pipe cross-section is the first side 15, and the lower side is the second side 16. The first side 15 faces the opening and is the windward side. The width of the first side 15 is narrow, which reduces the resistance when the flue gas enters. The pipe body is made of welded steel plates.

[0039] The first shape can also be any other shape, as long as the cross-sectional area of the pipe is the same as that of the circular pipe, and the width of the pipe along the first direction is narrower than that of the circular pipe to increase the distance between the pipes.

[0040] Optionally, the ratio of the first length to the second length is 2 - 30. The larger the ratio of the two, the flatter and longer the pipe cross-section. After installation, the distance between the pipes is larger, and the resistance of the flue gas passing through is smaller. The flatness and length of the pipe cross-section can be selected according to the resistance requirement of the flue gas passing through. Preferably, the ratio of the first length to the second length is 2 - 3, which is convenient for manufacturing.

[0041] Embodiment 2

[0042] This embodiment provides a water-cooled wall device, as Figure 1 shown, which includes a plurality of water-cooled wall pipes in Embodiment 1 and a header 21. A plurality of water-cooled wall pipes are arranged in parallel at intervals, and their upper and lower ends are respectively welded and connected to the header 21.

[0043] During use, the header 21 and the water-cooled wall pipes are installed outside the opening where the bypass pipe is connected to the boiler. After the water-cooled wall device is installed on the outer wall of the boiler, the gap between the water-cooled wall pipes is large, and the resistance of the flue gas passing through the water-cooled wall pipes through the boiler opening is small.

[0044] One of any two adjacent water-cooled wall pipes is a deflecting pipe 11, and the other water-cooled wall pipe is a vertical pipe 12. The upper end of the deflecting pipe 11 connected to the header 21 is provided with a first elbow joint 13, and the lower end is provided with a second connection joint. The elbow joint, the first end of the vertical pipe 12 connected to the header 21 are arranged along a first straight line; the flue gas flow direction is the front-back direction, where the side close to the opening is the front side, and the side far from the opening is the rear side. The end of the second end of the first elbow joint 13 extends to the rear side of the vertical pipe 12, and the deflecting pipe 11 is connected to the second end of the first elbow joint 13 and extends vertically.

[0045] The diversion pipe 11 is arranged at the rear side of the vertical pipe 12 through an elbow joint. Along the flue gas flow direction, the vertical pipe 12 and the diversion pipe 11 overlap front and back, and their projection surfaces on the boiler opening are the same. The gap between the pipes perpendicular to the flue gas flow direction increases, effectively increasing the effective area through which the flue gas can pass. The resistance of the flue gas when passing through the water wall pipes is further reduced, which is beneficial to reducing the resistance and energy consumption of the boiler system.

[0046] For example, referring to Figure 1 , six water wall pipes are shown in the figure. Before the improvement, the upper and lower ends of the six water wall pipes are respectively connected to the upper and lower headers 21 and extend vertically, and the individual water wall pipes are arranged in parallel at intervals. In the present invention, through the first elbow joint 13 and the second elbow joint 14, one of the water wall pipes on the right side in two adjacent water wall pipes extends to the rear side of the water wall pipe on the left side. The water wall pipe at the rear side serves as the diversion pipe 11 and overlaps with the unchanged vertical pipe 12 front and back. The effective cross-section through which the flue gas can pass increases by nearly one time, greatly reducing the resistance of the flue gas passing through.

[0047] Referring to Figure 4 , for the water wall pipes arranged front and back along the flue gas flow direction, the first side 15 of the water wall pipe far from the opening faces the opening.

[0048] Embodiment 3

[0049] This embodiment provides a boiler, which includes the water wall device in Embodiment 2. For the boiler with this structure, the resistance of the flue gas when passing through the bypass pipe is small, and the boiler system has low resistance and energy saving.

[0050] Obviously, the above embodiments are only examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or variations can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. And the obvious changes or variations derived therefrom are still within the protection scope of the present invention.

Claims

1. A water wall device, characterized in that, it includes water wall pipes and headers (21). A plurality of the water wall pipes are arranged in parallel at intervals, and their upper and lower ends are respectively communicated with the header (21). The water wall pipes include: a pipe body, which is adapted to be arranged outside the opening where the bypass pipe is communicated with the boiler; the cross-sectional shape of the pipe body is a first shape. The length of the first shape parallel to the flue gas flow direction is a first length, and the length perpendicular to the flue gas flow direction is a second length. The first length is greater than the second length, and the ratio of the first length to the second length is 2 - 30; the cross-sectional area of the pipe body is the same as that of the adjacent circular water wall pipes above and below it; one of any two adjacent water wall pipes is a deflecting pipe (11), and the other water wall pipe is a vertical pipe (12). The upper end of the deflecting pipe (11) connected to the header (21) is provided with a first elbow joint (13), and the lower end is provided with a second connection joint. The first ends of the elbow joint and the vertical pipe (12) connected to the header (21) are arranged along a first straight line; the flue gas flow direction is the front - rear direction, where the side close to the opening is the front side, and the side far from the opening is the rear side. The end of the second end of the first elbow joint (13) extends to the rear side of the vertical pipe (12). The deflecting pipe (11) is connected to the second end of the first elbow joint (13) and extends vertically. The deflecting pipe (11) is arranged at the rear side of the vertical pipe (12) through the elbow joint. Along the flue gas flow direction, the vertical pipe (12) and the deflecting pipe (11) overlap front - rear, and their projection surfaces on the boiler opening are the same.

2. The water wall device according to claim 1, characterized in that, the surface of the pipe body facing the opening is an arc surface.

3. The water wall device according to claim 2, characterized in that, the first shape is a fusiform.

4. The water wall device according to claim 2, characterized in that, the first shape is an ellipse.

5. The water wall device according to claim 2, characterized in that, the first shape is a water droplet shape.

6. The water wall device according to claim 5, characterized in that, the narrower side of the water droplet shape is the first side (15), and the wider side is the second side (16). After the pipe body is installed, the first side (15) faces the opening.

7. The water wall device according to claim 1, characterized in that, the ratio of the first length to the second length is 2 - 3.

8. A boiler, characterized in that, it includes the water wall device according to any one of claims 1 - 7.

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