Flue built-in blowing device

Abstract

The present invention provides a flue-mounted spraying device comprising a distribution valve and multiple powder delivery branches for delivering catalyst powder into the flue housing. The distribution valve is mounted on the flue housing, with its powder delivery inlet communicating with the exterior of the flue housing and its outlet connecting to the powder delivery branches within the flue housing. Each powder delivery branch is equipped with multiple nozzles, each designed to spray catalyst powder in the same direction as the flue gas flow within the flue housing. This invention addresses the technical problem of uneven mixing of catalyst powder injected into the flue with the flue gas, resulting in low desulfurization efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of flue gas purification, and further to a flue gas desulfurization device, in particular to a flue built-in injection device. Background Art

[0002] Excessive flue gas emissions are a major cause of atmospheric pollution. Environmental protection authorities strictly control flue gas emissions, requiring metallurgical enterprises to meet emission standards. Flue gas primarily consists of NOx, SO2, COx, and moisture. SO2, which accounts for 38% of flue gas mass, is a major contributor to air pollution and acid rain. Flue gas desulfurization is essential to meet emission standards.

[0003] At present, the main methods of flue gas desulfurization at home and abroad can be roughly divided into three types: dry method, semi-dry method and wet method.

[0004] Compared to wet systems, dry flue gas desulfurization (FGD) is widely popular due to its simple equipment, small footprint, low investment and operating costs, easy operation, low energy consumption, easy disposal of products, and the absence of a sewage treatment system. The dry FGD process primarily involves injecting fine catalyst powder into the flue along with compressed air, allowing it to fully mix and contact with the flue gas and react with the SO2 in the flue gas to produce sulfate particles. These sulfate particles, along with fly ash, are collected by a dust collector or discharged through a chimney, achieving the purpose of FGD. Byproducts recovered by the dust collector can be reused as chemical products. The greatest advantage of dry FGD is that no wastewater or waste acid is discharged during treatment, reducing secondary pollution. The disadvantage is low FGD efficiency and bulky equipment.

[0005] There are various structures of dry flue gas desulfurization devices, for example: multiple nozzles can be telescopically arranged in the vertical direction of the flue, and each nozzle has multiple nozzle holes. When it is necessary to spray the catalyst into the flue, the nozzle is controlled to extend into the flue, and the external powder bin is connected to the nozzle through the blowing pipe. The nozzle can rotate along its own axis in the flue, so as to blow the powder (catalyst powder that can react with SO2 to produce sulfate) into the flue through each nozzle hole; when it is not necessary to spray the catalyst into the flue, the nozzle is controlled to withdraw from the flue. However, since the powder is sprayed into the flue in a divergent manner from a point on the inner wall of the flue, the powder is easy to hit the inner wall of the flue, which can easily cause the accumulation of powder; in addition, if the environment where the device is located is dusty, dust is likely to block the nozzle movement, and the normal operation cannot be guaranteed. Another example: insert the powder spraying pipe directly into the flue, and inject compressed air mixed with powder into the flue to achieve mixing of flue gas and powder. However, this device cannot mix the flue gas and powder very unevenly, resulting in low desulfurization efficiency and poor desulfurization effect.

[0006] Currently, there is no effective solution to the problem that the catalyst powder injected into the flue is not evenly mixed with the flue gas and the desulfurization efficiency is low.

[0007] Therefore, the inventors, relying on their many years of experience and practice in related industries, have proposed a flue-mounted blowing device to overcome the defects of the prior art. Summary of the Invention

[0008] The purpose of the present invention is to provide a flue-mounted blowing device, which can greatly improve the uniformity of catalyst injection in the flue, ensure that the catalyst and flue gas are in full contact in the flue, so that the SO2 in the flue gas reacts fully, improve the efficiency of flue gas dry desulfurization, and avoid flue gas pollution to the environment.

[0009] Another object of the present invention is to provide a flue-mounted blowing device with a simple structure and easy installation. The blowing device can be installed by simply opening a hole in the flue and connecting it. During operation, the blowing device can evenly disperse the injected catalyst through the flue gas flowing in the flue without adding additional power. It is energy-saving and environmentally friendly and is suitable for popularization and use.

[0010] The purpose of the present invention can be achieved by adopting the following technical solutions:

[0011] The present invention provides a flue-mounted blowing device, which includes a distribution valve and a plurality of powder feeding branches for conveying catalyst powder into a flue housing, wherein:

[0012] The distribution valve is used to be arranged on the flue shell, the powder spraying inlet of the distribution valve is used to be connected to the outside of the flue shell, and the powder spraying outlet of the distribution valve is used to be connected to each of the powder delivery branches located in the flue shell. Each of the powder delivery branches is provided with multiple nozzles, and the spraying direction of the catalyst powder by each nozzle is used to be the same as the flow direction of the flue gas in the flue shell.

[0013] In a preferred embodiment of the present invention, the powder conveying branches are arranged in a divergent shape.

[0014] In a preferred embodiment of the present invention, each of the powder conveying branch pipes is located on the same cross section in the flue shell, so that the catalyst powder sprayed from each of the nozzles can be evenly distributed over the entire cross section in the flue shell.

[0015] In a preferred embodiment of the present invention, the powder spraying inlet of the distribution valve is used to pass through the flue casing and extend to the outside of the flue casing.

[0016] In a preferred embodiment of the present invention, the nozzle located on each of the powder conveying branch pipes includes multiple first nozzles and one second nozzle, one end of the powder conveying branch pipe is connected to the powder spray outlet of the distribution valve, and the second nozzle is arranged at the other end of the powder conveying branch pipe, and the first nozzles are arranged continuously and at intervals along the extension direction of the powder conveying branch pipe.

[0017] In a preferred embodiment of the present invention, the distance between each two adjacent first nozzles and the distance between the second nozzle and its adjacent first nozzle are equal.

[0018] In a preferred embodiment of the present invention, the air inlet end of the second nozzle to the air outlet end of the second nozzle is an arc-shaped structure that gradually tilts toward the flow direction of the flue gas in the flue casing.

[0019] In a preferred embodiment of the present invention, the inner diameter of the second nozzle gradually decreases from the air inlet end of the second nozzle to the air outlet end of the second nozzle.

[0020] In a preferred embodiment of the present invention, the distribution valve is arranged on the top of the flue shell, each of the powder conveying branch pipes is arranged in a vertical direction, and the distance between each two adjacent powder conveying branch pipes is equal.

[0021] In a preferred embodiment of the present invention, the distribution valve includes a distribution valve body and multiple root branches, the distribution valve body is a cylindrical structure arranged in the vertical direction, the top of the distribution valve body is the powder spraying inlet of the distribution valve, the bottom end of the distribution valve body is connected to one end of each of the root branches, and the root branches are arranged divergently from top to bottom gradually away from the distribution valve body, and the other end of each of the root branches is the powder spraying outlet of the distribution valve.

[0022] In a preferred embodiment of the present invention, a fixed beam is provided between each of the powder conveying branch pipes, both ends of the fixed beam are used to connect with the inner wall of the flue shell, and the middle part of the fixed beam is respectively connected with the outer wall of each of the powder conveying branch pipes.

[0023] In a preferred embodiment of the present invention, there are multiple fixed beams, each of which is arranged in a horizontal direction, and each of the fixed beams is spaced apart from top to bottom.

[0024] In a preferred embodiment of the present invention, the inner cross-sectional area of ​​the distribution valve is larger than the sum of the inner cross-sectional areas of the powder conveying branches, and the sum of the inner cross-sectional areas of the powder conveying branches is larger than the sum of the inner cross-sectional areas of the nozzles.

[0025] In a preferred embodiment of the present invention, a gap is left between each of the nozzles and the inner wall of the flue shell.

[0026] In a preferred embodiment of the present invention, the powder injection inlet of the distribution valve is used to be connected to a compressed air pipeline, and the compressed air pipeline is connected to a bypass for injecting the catalyst powder.

[0027] As described above, the characteristics and advantages of the flue-mounted blowing device of the present invention are: the distribution valve is arranged on the flue shell, the powder spraying inlet of the distribution valve is connected to the compressed air pipeline located outside the flue shell, and the multiple powder spraying outlets of the distribution valve are connected to the multiple powder delivery branches located inside the flue shell. It has a simple structure and is easy to install. It only needs to open holes and connect on the flue shell to complete the installation of the distribution valve and the powder delivery branches. It can be installed and used on site and is highly practical. In addition, each powder conveying branch pipe is provided with a plurality of nozzles, and the spraying direction of the catalyst powder of each nozzle is the same as the flow direction of the flue gas in the flue casing. The catalyst powder sprayed by each nozzle can smoothly enter the interior of the flue casing and flow with the flue gas, and there will be no situation in which the catalyst powder hits the inner wall of the flue casing and accumulates on the inner wall, thereby improving the diffusion efficiency of the catalyst powder, ensuring that the catalyst powder can be evenly dispersed in the flue casing and fully contact the flue gas, so that gases such as SO2 in the flue gas can fully react with the catalyst powder, thereby improving the efficiency of dry desulfurization of flue gas, ensuring a good desulfurization effect, and avoiding pollution to the environment by gases such as SO2 in the flue gas. Moreover, in this flue gas purification process, the catalyst powder sprayed by each nozzle can make the sprayed catalyst powder evenly dispersed by the flue gas flowing in the flue casing, without adding additional power, energy saving and environmental protection, and suitable for popularization and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The following drawings are only intended to illustrate and explain the present invention, and are not intended to limit the scope of the present invention.

[0029] in:

[0030] Figure 1 : It is a three-dimensional diagram of the built-in flue blowing device of the present invention in the flue.

[0031] Figure 2 : It is a front view of the built-in flue blowing device of the present invention in the flue.

[0032] Figure 3 : It is a front view of the flue-mounted blowing device of the present invention, in which a fixed beam is arranged in the flue.

[0033] Figure 4 : It is a structural diagram of the flue built-in blowing device of the present invention.

[0034] Figure 5 : It is a partial cross-sectional view of the distribution valve in the built-in flue blowing device of the present invention.

[0035] Figure 6 : It is a partial cross-sectional view of the branch pipe in the built-in flue blowing device of the present invention.

[0036] The accompanying drawings in the present invention are:

[0037] 1. Distribution valve; 101. Distribution valve body;

[0038] 102. Root branch pipe; 2. Powder transport branch pipe;

[0039] 3. Nozzle; 301. First nozzle;

[0040] 302, second nozzle; 3021, air inlet end;

[0041] 3022, outlet end; 4, fixed beam;

[0042] 10. Flue casing. DETAILED DESCRIPTION

[0043] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described with reference to the accompanying drawings.

[0044] like Figures 1 to 6 As shown, the present invention provides a flue-mounted blowing device, which includes a distribution valve 1 and multiple powder delivery branches 2. The distribution valve 1 and the powder delivery branches 2 cooperate to transport catalyst powder into the flue housing 10, wherein: the distribution valve 1 is arranged on the flue housing 10, and the powder injection inlet of the distribution valve 1 is connected to the outside of the flue housing 10. A compressed air pipeline is provided on the outside of the flue housing 10, and a bypass is connected to the compressed air pipeline. Catalyst powder can be injected into the compressed air pipeline through the bypass. The catalyst powder is fully mixed with the compressed air in the compressed air pipeline before entering the distribution valve 1. The powder injection outlet of the distribution valve 1 is connected to the powder delivery branches 2 located in the flue housing 10. Each powder delivery branch 2 is provided with multiple nozzles 3. The direction of injection of the catalyst powder by each nozzle 3 is the same as the flow direction of the flue gas in the flue housing 10.

[0045] In the present invention, the distribution valve 1 is arranged on the flue shell 10, the powder spraying inlet of the distribution valve 1 is connected to the compressed air pipeline located outside the flue shell 10, and the multiple powder spraying outlets of the distribution valve 1 are connected to the multiple powder conveying branches 2 located inside the flue shell 10. It has a simple structure and is easy to install. It only needs to open holes and connect on the flue shell 10 to complete the installation of the distribution valve 1 and each powder conveying branch pipe 2. It can be installed and used on site and is highly practical. In addition, each powder conveying branch pipe 2 is provided with a plurality of nozzles 3, and the spraying direction of the catalyst powder of each nozzle 3 is the same as the flow direction of the flue gas in the flue casing 10. The catalyst powder sprayed through each nozzle 3 can smoothly enter the interior of the flue casing 10 and flow with the flue gas. There is no situation in which the catalyst powder hits the inner wall of the flue casing 10 and accumulates on the inner wall, thereby improving the diffusion efficiency of the catalyst powder, ensuring that the catalyst powder can be evenly dispersed in the flue casing 10 and fully contact the flue gas, so that gases such as SO2 in the flue gas can fully react with the catalyst powder, thereby improving the efficiency of dry desulfurization of flue gas, ensuring a good desulfurization effect, and avoiding pollution to the environment by gases such as SO2 in the flue gas. Moreover, in this flue gas purification process, the catalyst powder sprayed from each nozzle can make the sprayed catalyst powder evenly dispersed by the flue gas flowing in the flue casing 10, without adding additional power, energy saving and environmental protection, and suitable for promotion and use.

[0046] Specifically, such as Figures 1 to 4 As shown, each nozzle 3 is arranged in the same direction, and the direction of each nozzle 3 is the same as the flow direction of the flue gas in the flue housing 10, so that the injection direction from each nozzle 3 is the same as the flow direction of the flue gas in the flue housing 10. As a result, the catalyst powder ejected through each nozzle 3 can smoothly enter the interior of the flue housing 10 and flow along with the flue gas, thereby improving the diffusion efficiency of the catalyst powder and ensuring that the catalyst powder can be evenly dispersed in the flue housing 10 and fully contact with the flue gas, thereby improving the reaction efficiency. Therefore, during operation, it is necessary to first allow flue gas to flow inside the flue housing 10 before controlling each nozzle 3 to inject the catalyst powder into the flue housing 10.

[0047] Furthermore, the catalyst powder used may be, but is not limited to, baking soda (ie, sodium bicarbonate) powder.

[0048] In an optional embodiment of the present invention, Figures 1 to 3 As shown, the powder conveying branches 2 are arranged in a divergent shape so that the catalyst powder sprayed by each nozzle 3 on each powder conveying branch 2 can be distributed as evenly as possible in the flue casing 10, thereby increasing the contact area between the catalyst powder and the flue gas, and improving the degree of reaction between gases such as SO2 in the flue gas and the catalyst powder, thereby ensuring a good desulfurization effect.

[0049] Further, such as Figures 1 to 3As shown, each powder delivery branch pipe 2 is located on the same cross-section inside the flue casing 10, so that the catalyst powder sprayed by each nozzle 3 can be evenly distributed on the entire cross-section inside the flue casing 10, which can greatly improve the uniformity of the catalyst powder sprayed inside the flue casing 10, ensure that the catalyst powder and the flue gas can fully contact each other inside the flue casing 10, so that gases such as SO2 in the flue gas can fully react with the catalyst powder.

[0050] Further, such as Figures 1 to 3 As shown, the powder spraying inlet of the distribution valve 1 passes through the flue housing 10 and extends to the outside of the flue housing 10, thereby facilitating the connection of the powder spraying inlet of the distribution valve 1 with the compressed air pipeline.

[0051] Furthermore, the internal cross-sectional area of ​​the distribution valve 1 is larger than the sum of the internal cross-sectional areas of each powder conveying branch pipe 2, and the sum of the internal cross-sectional areas of each powder conveying branch pipe 2 is larger than the sum of the internal cross-sectional areas of each nozzle 3, so that there is a certain pressure difference between the distribution valve 1 and each powder conveying branch pipe 2 and between each powder conveying branch pipe 2 and each nozzle 3, so as to ensure that the flow velocity of the catalyst powder gradually increases from the distribution valve 1 to each powder conveying branch pipe 2 and from each powder conveying branch pipe 2 to each nozzle 3, so that the catalyst powder will not be retained during the flow process in the entire injection device, thereby ensuring the smooth injection of the catalyst powder.

[0052] Furthermore, a gap is left between each nozzle 3 and the inner wall of the flue shell 10 to prevent the catalyst powder from being directly sprayed onto the inner wall of the flue shell 10 .

[0053] In an optional embodiment of the present invention, Figures 1 to 4 、 Figure 6 As shown, the nozzle 3 located on each powder conveying branch pipe 2 includes multiple first nozzles 301 and one second nozzle 302. One end of the powder conveying branch pipe 2 is connected to the powder spraying outlet of the distribution valve 1, and the second nozzle 302 is arranged at the other end of the powder conveying branch pipe 2. The first nozzles 301 are arranged continuously and at intervals along the extension direction of the powder conveying branch pipe 2 to ensure that the nozzles 3 can be arranged as evenly as possible on the same cross-section inside the flue shell 10, so that the catalyst powder sprayed by each nozzle 3 can be evenly distributed inside the flue shell 10.

[0054] Further, such as Figures 1 to 4 As shown, the distance between each two adjacent first nozzles 301 and the distance between the second nozzle 302 and its adjacent first nozzle 301 are equal, thereby improving the uniform distribution effect of the catalyst powder.

[0055] In an optional embodiment of the present invention, Figure 6As shown, the air inlet end 3021 of the second nozzle 302 to the air outlet end 3022 of the second nozzle 302 is an arc-shaped structure that gradually tilts toward the flow direction of the flue gas in the flue shell 10. There is a smooth transition from the air inlet end 3021 to the air outlet end 3022 inside the second nozzle 302, thereby ensuring that the catalyst powder can be smoothly sprayed into the flue shell 10 and avoiding clogging the air outlet end 3022 of the second nozzle 302.

[0056] Further, such as Figure 6 As shown, the bending angle of the arc structure formed by the air inlet end 3021 of the second nozzle 302 to the air outlet end 3022 of the second nozzle 302 can be but not limited to 90°, ensuring that the direction of the catalyst powder ejected from the second nozzle 302 is the same as the flow direction of the flue gas in the flue casing 10.

[0057] Further, such as Figure 6 As shown, the inner diameter of the second nozzle 302 gradually decreases from the air inlet end 3021 of the second nozzle 302 to the air outlet end 3022 of the second nozzle, thereby forming a pressure difference between the air inlet end 3021 of the second nozzle 302 and the air outlet end 3022 of the second nozzle. The catalyst powder will gradually accelerate in the process of passing through the second nozzle 302, further preventing the catalyst powder from being retained in the second nozzle 302 and clogging the second nozzle 302.

[0058] In an optional embodiment of the present invention, Figures 1 to 3 As shown, the distribution valve 1 is arranged on the top of the flue shell 10, and each powder conveying branch pipe 2 is arranged in the vertical direction, and the distance between each adjacent powder conveying branch pipe 2 is equal, so as to ensure that each powder conveying branch pipe 2 is evenly distributed inside the flue shell 10 as much as possible.

[0059] Specifically, such as Figures 1 to 6 As shown, the distributing valve 1 includes a distributing valve body 101 and multiple root branches 102. The distributing valve body 101 is a cylindrical structure arranged in the vertical direction. The top of the distributing valve body 101 is the powder spraying inlet of the distributing valve 1, and the bottom end of the distributing valve body 101 is connected to one end of each root branch 102. The root branches 102 are arranged divergently from top to bottom gradually away from the distributing valve body 101, and the other end of each root branch 102 is the powder spraying outlet of the distributing valve 1.

[0060] In an optional embodiment of the present invention, Figure 3 As shown, a fixed beam 4 is provided between each powder conveying branch pipe 2, both ends of the fixed beam 4 are connected to the inner wall of the flue shell 10, and the middle part of the fixed beam 4 is connected to the outer wall of each powder conveying branch pipe 2. By setting the fixed beam 4, the stability between each powder conveying branch pipe 2 and the stability between the powder conveying branch pipe 2 and the flue shell 10 are improved.

[0061] Further, such as Figure 3 As shown, there are multiple fixed beams 4 , each fixed beam 4 is arranged in a horizontal direction, and each fixed beam 4 is spaced apart from top to bottom.

[0062] A specific embodiment of the present invention, as Figures 1 to 3 As shown in the figure: the high-temperature flue gas generated by sintering and converter steelmaking in a steel plant contains a large amount of SO2 gas. The catalyst powder enters the distribution valve 1 set at the top of the flue shell 10 along with the compressed air. Then, after being diverted by the distribution valve 1, it enters each powder conveying branch pipe 2. Then, it is sprayed into the interior of the flue shell 10 from the nozzle 3 set on each powder conveying branch pipe 2. The catalyst powder reacts with the SO2 in the flue gas to form sulfate particles. The sulfate particles are collected by the dust collector together with the fly ash in the flue gas, thereby purifying the flue gas. The total desulfurization efficiency is above 95%. The finer the catalyst powder, the more complete its contact with the flue gas, and the higher the desulfurization efficiency. In this example, the catalyst powder can be made by crushing baking soda powder to about 20 microns, which achieves the best desulfurization effect. In this embodiment, the sum of the internal cross-sectional areas of the powder conveying branches 2 is 97% of the internal cross-sectional area of ​​the distribution valve 1, and the sum of the internal cross-sectional areas of the nozzles 3 on each powder conveying branch 2 is 90% to 98% of the internal cross-sectional area of ​​the powder conveying branch 2, thereby ensuring that the catalyst powder will not be retained or blocked in the injection device.

[0063] In this embodiment, four powder conveying branch pipes 2 are arranged in the vertical direction inside the flue shell 10, and the four powder conveying branch pipes 2 are arranged symmetrically on the left and right, and the distance between two adjacent powder conveying branch pipes 2 is approximately 1 / 4 of the inner diameter of the flue shell 10; in this embodiment, the distance between each nozzle 3 and the inner wall of the flue shell 10 is greater than 500 mm, ensuring that the catalyst powder will not be directly sprayed onto the inner wall of the flue shell 10.

[0064] The characteristics and advantages of the flue built-in blowing device of the present invention are:

[0065] 1. The built-in flue blowing device has a simple structure and is easy to install. It only requires opening holes in the flue shell 10 to complete the installation of the distribution valve 1 and each powder conveying branch pipe 2. It can be installed and used on site, is highly practical, energy-saving and environmentally friendly, and is suitable for promotion and use.

[0066] 2. The catalyst powder sprayed by each nozzle 3 in the built-in flue blowing device can be evenly distributed over the entire cross-section of the flue shell 10, which can greatly improve the uniformity of the catalyst powder sprayed in the flue shell 10, ensure that the catalyst powder and the flue gas can fully contact in the flue shell 10, so that gases such as SO2 in the flue gas can fully react with the catalyst powder, thereby improving the efficiency of dry desulfurization of the flue gas, ensuring a good desulfurization effect, and avoiding pollution of the environment by gases such as SO2 in the flue gas.

[0067] 3. The orientation of each nozzle 3 in the flue-built-in blowing device is the same as the flow direction of the flue gas in the flue casing 10, so that the injection direction from each nozzle 3 is the same as the flow direction of the flue gas in the flue casing 10, thereby improving the diffusion efficiency of the catalyst powder and ensuring that the catalyst powder can be evenly dispersed in the flue casing 10 and fully contact the flue gas, thereby improving the reaction efficiency without adding additional power.

[0068] The above description is only an illustrative embodiment of the present invention and is not intended to limit the scope of the present invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principle of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A flue built-in blowing device, characterized in that: The flue-mounted injection device comprises a distribution valve (1) for conveying catalyst powder into a flue casing (10) and a plurality of powder conveying branches (2), wherein: The distribution valve (1) is used to be arranged on the flue shell (10), the powder spraying inlet of the distribution valve (1) is used to communicate with the outside of the flue shell (10), and the powder spraying outlet of the distribution valve (1) is used to be connected to each of the powder conveying branch pipes (2) located in the flue shell (10), and each of the powder conveying branch pipes (2) is provided with a plurality of nozzles (3), each of the nozzles (3) is arranged in the same direction, and the direction of each of the nozzles (3) is the same as the flow direction of the flue gas in the flue shell (10), so that the spraying direction of the catalyst powder from each of the nozzles (3) is the same as the flow direction of the flue gas in the flue shell (10); The inner cross-sectional area of ​​the distribution valve (1) is larger than the sum of the inner cross-sectional areas of the powder conveying branch pipes (2), and the sum of the inner cross-sectional areas of the powder conveying branch pipes (2) is larger than the sum of the inner cross-sectional areas of the nozzles (3), so that there is a pressure difference between the distribution valve (1) and the powder conveying branch pipes (2), and between the powder conveying branch pipes (2) and the nozzles (3); The nozzle (3) located on each of the powder conveying branch pipes (2) includes a plurality of first nozzles (301) and a second nozzle (302); one end of the powder conveying branch pipe (2) is connected to the powder spraying outlet of the distribution valve (1); the second nozzle (302) is arranged at the other end of the powder conveying branch pipe (2); and the first nozzles (301) are arranged continuously and at intervals along the extension direction of the powder conveying branch pipe (2); The air inlet end (3021) of the second nozzle (302) and the air outlet end (3022) of the second nozzle (302) are arc-shaped structures that gradually tilt toward the flow direction of the flue gas in the flue shell (10), and there is a smooth transition from the air inlet end (3021) to the air outlet end (3022) inside the second nozzle (302); the inner diameter of the second nozzle (302) gradually decreases from the air inlet end (3021) to the air outlet end (3022), so as to form a pressure difference between the air inlet end (3021) and the air outlet end (3022), thereby accelerating the catalyst powder passing through the second nozzle (302); The distribution valve (1) is arranged on the top of the flue shell (10), and each of the powder conveying branch pipes (2) is arranged in a vertical direction, and the distance between each two adjacent powder conveying branch pipes (2) is equal; the distribution valve (1) comprises a distribution valve body (101) and a plurality of root branch pipes (102), the distribution valve body (101) is a cylindrical structure arranged in the vertical direction, the top of the distribution valve body (101) is the powder spraying inlet of the distribution valve (1), the bottom end of the distribution valve body (101) is connected to one end of each of the root branch pipes (102), and each of the root branch pipes (102) is arranged in a divergent shape from top to bottom gradually away from the distribution valve body (101), and the other end of each of the root branch pipes (102) is each of the powder spraying outlets of the distribution valve (1).

2. The flue-mounted spraying device according to claim 1, characterized in that: The powder conveying branch pipes (2) are arranged in a divergent manner.

3. The flue-mounted spraying device according to claim 2, characterized in that: Each of the powder conveying branch pipes (2) is located on the same cross section in the flue shell (10), so that the catalyst powder ejected from each of the nozzles (3) can be evenly distributed over the entire cross section in the flue shell (10).

4. The flue-mounted spraying device according to claim 1, wherein: The powder spraying inlet of the distribution valve (1) is used to pass through the flue housing (10) and extend to the outside of the flue housing (10).

5. The flue-mounted spraying device according to claim 1, wherein: The distance between each adjacent two first nozzles (301) and the distance between the second nozzle (302) and its adjacent first nozzle (301) are equal.

6. The flue-mounted spraying device according to claim 1, characterized in that: A fixed beam (4) is provided between each of the powder conveying branch pipes (2), and both ends of the fixed beam (4) are used to be connected to the inner wall of the flue shell (10), and the middle of the fixed beam (4) is respectively connected to the outer wall of each of the powder conveying branch pipes (2).

7. The flue-mounted spraying device according to claim 6, characterized in that: There are a plurality of fixed beams (4), each of the fixed beams (4) is arranged in a horizontal direction, and each of the fixed beams (4) is spaced apart from top to bottom.

8. The flue-mounted spraying device according to claim 1, wherein: A gap is left between each nozzle (3) and the inner wall of the flue shell (10).

9. The flue-mounted spraying device according to claim 1, wherein: The powder injection inlet of the distribution valve (1) is used to be connected to a compressed air pipeline, and the compressed air pipeline is connected to a bypass for injecting the catalyst powder.

Images