Denitration device

Abstract

The utility model discloses a denitration device which is used for removing nitric oxide in smelting acid-making flue gas, the denitration device comprises a tower body, a pattern plate, a demister and a first liquid receiving pipe, and the tower body is provided with a liquid outlet; the tubesheet is erected in the tower body, and a plurality of flow guide holes are formed in the tubesheet; the demister is vertically arranged on the pattern plate, a flue gas channel is formed in the demister, the flue gas channel is used for circulating smelting acid-making flue gas, and the flow guide hole is communicated with the flue gas channel; the first liquid receiving pipe is communicated with the flow guide hole and the liquid outlet. Nitrogen oxides in the smelting acid-making flue gas are condensed into sulfur ammonium salt liquid drops on the surface of the demister, and the sulfur ammonium salt liquid drops automatically flow to the pattern plate and are led out of the liquid outlet through the flow guide hole and the liquid receiving pipe, so that denitration under the condition of no addition of a denitration reagent is realized, nitrate crystals are effectively prevented from being attached to the surface of the demister or the wall surface of the tower body, and the service life of the demister is prolonged. The energy efficiency of sulfuric acid production equipment is improved, and the production energy consumption is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of sulfuric acid production, and more specifically, to a denitrification device for removing nitrogen oxides from smelting acid flue gas. Background Art

[0002] In the relevant technology, the denitrification methods in the sulfuric acid production process mainly include SNCR denitrification, SCR denitrification and ozone denitrification. Among them, SNCR denitrification requires spraying amine liquid in the smelting furnace. Long-term operation will form crystallized salt on the inner wall of the furnace, reducing the energy efficiency of the smelting furnace. SCR denitrification and ozone denitrification are mainly carried out at the back end of the smelting flue gas acid production, resulting in a certain amount of nitrate remaining in the finished acid. When the operating conditions of the flue gas acid production dry absorption process flue gas ... condensation, resulting in reduced energy efficiency of the demister. In summary, the denitrification device installed in the existing smelting flue gas acid production process cannot effectively solve the problem of nitrate crystallization that is easy to form in the front-end dry absorption process, resulting in reduced equipment energy efficiency and increased production energy consumption. Utility Model Content

[0003] The embodiment of the present application provides a denitrification device, which is at least used to improve the problem of nitrate formation in the smelting flue gas acid production process.

[0004] The denitrification device of the embodiment of the present application is used to remove nitrogen oxides in the smelting acid-making flue gas. The denitrification device includes a tower body, a flower plate, a demister and a first liquid receiving pipe, wherein the tower body is provided with a liquid discharge port; the flower plate is mounted in the tower body, and a plurality of guide holes are formed on the flower plate; the demister is erected on the flower plate, and a flue gas channel is formed in the demister, and the flue gas channel is used to circulate the smelting acid-making flue gas, and the guide holes are connected to the flue gas channel; the first liquid receiving pipe connects the guide holes and the liquid discharge port.

[0005] In the denitrification device of the embodiment of the present application, the smelting acid production flue gas enters the tower body and flows through the flue gas channel. The nitrogen oxides in the smelting acid production flue gas combine with the sulfur element in the flue gas to form ammonium sulfate salts under the operating conditions of the demister. The ammonium sulfate salt droplets condense on the surface of the demister to form ammonium sulfate salt droplets. The ammonium sulfate salt droplets are discharged to the drain port through the guide holes and the liquid receiving pipe. Under the condition of eliminating the need to spray denitrification reagents, the nitrogen oxides in the smelting acid production flue gas are effectively removed, and the adhesion of nitrate crystals to the demister surface or the tower body wall is avoided to a certain extent, thereby improving the energy efficiency of sulfuric acid production equipment and reducing production energy consumption. In addition, the denitrification device of the embodiment of the present application effectively denitrifies at the front end of the acid production process of smelting acid production flue gas, which can reduce the nitrate content in the finished acid and improve the product quality of the finished acid.

[0006] In some embodiments, the drain port is formed on the side wall of the tower body, and the first liquid receiving pipe includes a first pipe section and a second pipe section. The first pipe section is connected to the flower plate and communicates with the guide hole, and the second pipe section is connected to the side wall and communicates with the drain port. At least part of the first pipe section forms an angle with the second pipe section.

[0007] In this way, the first pipe section is connected to the diversion hole on the flower plate, and the second pipe section is connected to the drainage port on the side wall. At least part of the first pipe section forms an angle with the second pipe section, thereby forming a curved drainage route to adapt to the arrangement of components inside the tower body.

[0008] In some embodiments, there are multiple first pipe segments, and the multiple first pipe segments are connected to the diversion holes in a one-to-one correspondence, and the multiple first pipe segments converge into the second pipe segment.

[0009] In this way, multiple first pipe sections are connected to the guide holes in a one-to-one correspondence, and multiple first pipe sections converge into the second pipe section, so that the ammonium sulfate droplets collected by the multiple guide holes converge in the second pipe section and are discharged. When the nitrate is discharged, a large liquid flow rate is formed, which is convenient for self-flow and not easy to crystallize, and the drainage effect is better.

[0010] In some embodiments, there are multiple demisters, and the multiple demisters are arranged horizontally on the flower plate at intervals. A first flue gas channel is formed inside the demister, and a second flue gas channel is formed between the outer surfaces of adjacent and opposite demisters. The first flue gas channel and the second flue gas channel are connected.

[0011] In this way, by increasing the number of demisters, multiple demisters are arranged at intervals on the flower plate, thereby increasing the contact area between the demisters and the smelting acid flue gas, which is conducive to sufficient denitrification.

[0012] In some embodiments, the guide hole is set on the flower plate away from the demister. The demister is a hollow cylindrical structure. A guide channel is formed in the cylinder wall of the demister. The guide channel is used to guide the droplets condensed on the inner wall of the demister to flow to the outer wall of the demister.

[0013] In this way, the demister has a hollow cylindrical structure, and the smelting acid-making flue gas can flow inside and outside the cylinder wall of the demister. The guide hole is set on the flower plate away from the demister, so that the guide hole is connected with the flue gas channel formed on the outer wall of the demister. The droplets condensed on the inner wall are guided to the outer wall of the demister through the guide channel, so that the guide hole and the first liquid receiving pipe can collect and discharge the ammonium sulfate droplets formed inside and outside the demister cylinder together.

[0014] In some embodiments, the cylinder wall of the demister includes a fiber layer and a wire mesh layer. Both the fiber layer and the wire mesh layer have porous structures, and the mesh holes of the fiber layer are finer than those of the wire mesh layer. The wire mesh layer is arranged outside the fiber layer, and the fiber layer and the wire mesh layer together form a diversion channel.

[0015] In this way, the fiber layer and the wire mesh layer are both porous structures, and the mesh holes of the fiber layer are finer than those of the wire mesh layer. The wire mesh layer is arranged outside the fiber layer, and the fiber layer and the wire mesh layer jointly form a diversion channel, so that the fiber layer can easily collect droplets formed on the inner wall of the demister, and the wire mesh layer continues to discharge the droplets collected by the fiber layer outward. The diversion channel utilizes the arrangement of the porous structure in the cylinder wall to realize flow collection and drainage.

[0016] In some embodiments, the flower plate is formed with a mounting hole and is provided with a hollow base for docking the mounting hole. The demister is a hollow cylindrical structure and is upright on the hollow base. The inner wall surface of the hollow base is formed with a collecting trough; the denitrification device includes a second liquid receiving pipe, which connects the collecting trough and the discharge port.

[0017] In this way, by setting a collecting groove on the inner wall of the hollow base, the collecting groove is connected to the second liquid receiving pipe, so that the ammonium sulfate droplets formed on the inner surface of the demister can be directly discharged to the outside of the tower body through the second liquid receiving pipe.

[0018] In some embodiments, the denitrification device includes a drainage trough and a first pipeline, the first pipeline connects the drainage port and the drainage trough, and the drainage trough is used to accumulate ammonium sulfate solution.

[0019] In this way, the drain port and the drain trough are connected through the first pipeline, so that the ammonium sulfate droplets are discharged into the drain trough. The ammonium sulfate droplets are enriched in the drain trough and accumulated to form an ammonium sulfate solution, which is convenient for centralized discharge and post-processing.

[0020] In some embodiments, the denitrification device includes a second pipeline and a post-processing mechanism, a delivery pump is provided on the second pipeline, the drainage tank and the post-processing mechanism are connected through the second pipeline liquid line, and the post-processing mechanism is used to harmlessly treat the ammonium sulfate solution.

[0021] In this way, the second pipeline and the delivery pump discharge the ammonium sulfate salt solution in the drainage tank to the post-processing mechanism, so that the ammonium sulfate salt solution is harmlessly treated, thereby achieving the purpose of environmental protection.

[0022] In some embodiments, the drain trough and / or the first pipeline and / or the second pipeline are provided with a heat preservation mechanism, and the heat preservation mechanism is used to keep the drain trough and / or the first pipeline and / or the second pipeline warm.

[0023] In this way, the drainage trough and / or the first pipeline and / or the second pipeline are heated by the insulation mechanism, so that the ammonium sulfate solution is not easy to crystallize in the drainage trough, the first pipeline, the second pipeline and other transportation facilities after being discharged from the tower body, thereby ensuring that the denitrification by-products can be discharged and post-processed smoothly, and at the same time improving the service life of the drainage trough, the first pipeline, the second pipeline and other transportation facilities.

[0024] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0026] Figure 1 Schematic diagram of the structure of the denitrification device according to the embodiment of the present application;

[0027] Figure 2 It is a partial structural schematic diagram of a denitrification device according to an embodiment of the present application;

[0028] Figure 3 This is a schematic diagram of the structure of the flower plate in a top view according to an embodiment of the present application;

[0029] Figure 4 is a schematic cross-sectional structural diagram of a first liquid receiving pipe according to an embodiment of the present application;

[0030] Figure 5 Schematic diagram of the cross-sectional structure of the demister according to the embodiment of the present application;

[0031] Figure 6 This is a schematic diagram of the connection between the second liquid receiving pipe and the collecting tank in an embodiment of the present application;

[0032] Figure 7 It is a schematic structural diagram of a denitrification device in some other embodiments of the present application.

[0033] Description of main component symbols:

[0034] 100-denitrification device; 10-tower body; 11-drain port; 12-tower top; 13-tower bottom; 14-side wall; 16-spray assembly; 20-flower plate; 21-diversion hole; 22-mounting hole; 23-hollow base; 231-collecting trough; 30-demister; 31-cylinder wall; 311-diversion channel; 312-fiber layer; 313-wire mesh layer; 314-inner frame; 315-outer baffle; 3 2-smoke channel; 321-first smoke channel; 322-second smoke channel; 40-first liquid receiving pipe; 41-first pipe section; 42-second pipe section; 43-second liquid receiving pipe; 50-installation assembly; 51-fixing bracket; 52-interface flange; 60-drain trough; 61-delivery pump; 62-liquid level gauge; 71-first pipeline; 72-second pipeline; 80-post-processing mechanism; 90-insulation mechanism. DETAILED DESCRIPTION

[0035] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and should not be understood as limiting the present application.

[0036] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present application, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0037] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections, electrical connections, or mutual communication; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0038] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0039] The disclosure below provides many different embodiments or examples for realizing different structures of the present application. In order to simplify the disclosure of the present application, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present application. In addition, the present application may repeat reference numbers and / or reference letters in different examples, and such repetition is for the purpose of simplicity and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present application provides examples of various specific processes and materials, but those of ordinary skill in the art will appreciate the application of other processes and / or the use of other materials.

[0040] The denitrification device 100 of the embodiment of the present application is used to remove nitrogen oxides in the smelting acid-making flue gas. The denitrification device 100 includes a tower body 10, a flower plate 20, a demister 30 and a first liquid receiving pipe 40, wherein the tower body 10 is provided with a drain port 11; the flower plate 20 is erected in the tower body 10, and a plurality of guide holes 21 are formed on the flower plate 20; the demister 30 is erected on the flower plate 20, and a flue gas channel 32 is formed in the demister 30, and the flue gas channel 32 is used to circulate the smelting acid-making flue gas, and the guide holes 21 are connected to the flue gas channel 32; the first liquid receiving pipe 40 connects the guide holes 21 and the drain port 11.

[0041] In the denitrification device 100 of the embodiment of the present application, the smelting acid production flue gas enters the tower body 10 and flows through the flue gas channel 32. The nitrogen oxides in the smelting acid production flue gas combine with the sulfur element in the flue gas to form nitrates under the operating conditions of the demister 30, and condense into ammonium sulfate droplets on the surface of the demister 30. The ammonium sulfate droplets are discharged to the drain port 11 through the guide hole 21 and the first liquid receiving pipe 40. Under the condition of eliminating the need for additional denitrification reagents, the nitrogen oxides in the smelting acid production flue gas are effectively removed, and the attachment of nitrate crystals to the surface of the demister 30 or the wall of the tower body 10 is avoided to a certain extent, thereby improving the energy efficiency of the sulfuric acid production equipment and reducing production energy consumption. In addition, the denitrification device 100 of the embodiment of the present application effectively denitrifies at the front end of the acid production process of the smelting acid production flue gas, which can reduce the nitrate content in the finished acid and improve the product quality of the finished acid.

[0042] Specifically, smelting acid flue gas is a product of the smelting of non-ferrous metal ores such as copper. Due to its high sulfur content, it is typically used in the acid production process as a raw material for the production of sulfuric acid. The tower body 10 can be a conventional absorption tower or a separate tower-shaped device. A flower plate 20 is installed within the tower body 10 to distinguish between different functional areas within the tower body 10. The drain port 11 is a through hole provided on the wall of the tower body 10, connecting the interior of the tower body 10 with the external environment.

[0043] Alternatively, the demister 30 may be a fiber demister, a tube bundle demister 30, a flat plate demister 30, a ridge demister 30, a baffle demister 30, or the like. The demister 30 may include a repetitive structure such as corrugated blades, baffles, and tube bundles to increase surface area. The flue gas passage 32 may be formed inside and outside the demister 30. For example, the demister 30 may be hollow, with a first flue gas passage 321 formed inside the demister 30 and a second flue gas passage 322 formed in the vacant area within the tower body 10 outside the demister 20.

[0044] Optionally, the flower plate 20 is mounted within the tower body 10, and the shape and dimensions of the flower plate 20 match the cross-sectional shape and dimensions of the tower body 10. The demister 30 can be vertically mounted on the flower plate 20, with the end of the demister 30 along the flow direction of the smelting acid flue gas in the flue gas channel 32 connected to the flower plate 20 so that ammonium sulfate droplets formed on the surface of the demister 30 can flow onto the flower plate 20.

[0045] Smelting acid flue gas enters the tower body 10 from the bottom 13 of the tower, and a flower plate 20 is installed on the upper part of the tower body 10. A spray assembly 16 is installed below the flower plate 20 in the tower body 10. Spray assembly 16 is used to spray concentrated sulfuric acid into the tower body 10. It should be noted that nitrogen oxides in the smelting acid flue gas come into contact with the sprayed acid below the spray assembly 16 and easily combine with SO2 or SO3 to form ammonium sulfate (mainly NOHSO4), which is soluble in sulfuric acid. When the temperature of the ammonium sulfate droplets is below 70°C, the solubility of the ammonium sulfate in sulfuric acid decreases, making it easy for crystals to precipitate.

[0046] Smelting acid production flue gas carrying ammonium sulfate enters above the flower plate 20 and flows through the flue gas channel 32. The surface temperature of the demister 30 is slightly lower than the temperature of the acid mist, thereby liquefying the "fog" components in the smelting acid production flue gas to achieve a demisting effect. The denitrification device of the present embodiment utilizes the surface of the demister 30 to condense ammonium sulfate droplets, causing the ammonium sulfate droplets to flow along the surface of the demister 30 toward the flower plate 20, converge at the guide holes 21 on the flower plate 20, and ultimately flow into the first liquid receiving pipe 40 and be discharged from the tower body 10 through the drain port 11.

[0047] There is at least one flow guide hole 21. To improve flow collection efficiency, the number of flow guide holes 21 can be multiple. The location of the flow guide holes 21 on the panel 20 is not limited. For example, the plurality of flow guide holes 21 are distributed near the geometric center of the panel 20, with a certain distance between each two adjacent flow guide holes 21. For another example, if the panel 20 is circular, the demisters 30 are spaced relatively evenly on the panel 20, and the plurality of flow guide holes 21 are distributed symmetrically about the center of the panel 20.

[0048] Optionally, the diameter of the guide hole 21 is smaller than the cross-sectional size of the smoke channel 32 .

[0049] One end of the first liquid receiving pipe 40 is connected to the guide hole 21 , and the other end can be connected to or plugged into the drain port 11 , and can also extend through the drain port 11 to the outside of the tower body 10 to discharge the ammonium sulfate droplets to the outside of the tower body 10 .

[0050] See also Figure 1 In some embodiments, the tower body 10 includes a tower top 12 and a tower bottom 13 opposite to each other, and a side wall 14 connecting the tower top 12 and the tower bottom 13. The demister 30 is arranged on the side of the flower plate 20 facing the tower top 12, and the first liquid receiving pipe 40 is arranged on the side of the flower plate 20 facing away from the demister 30.

[0051] In this way, the demister 30 is arranged on the side of the flower plate 20 facing the tower top 12, and the first liquid receiving pipe 40 is arranged on the side of the flower plate 20 facing away from the demister 30, so that a height difference is formed between the first liquid receiving pipe 40 and the surface of the demister 30, so that the ammonium sulfate droplets formed by the smelting acid-making flue gas flowing through the flue gas channel 32 can flow into the first liquid receiving pipe 40 by gravity.

[0052] Specifically, this application defines the direction from the tower top 12 toward the tower bottom 13 as "top-to-bottom." Smelting acid flue gas can enter the tower body 10 from the tower top 12 and ultimately exit the tower body 10 from the tower bottom 13. To utilize gravitational potential energy to guide the self-flow of droplets, the direction from the tower top 12 toward the tower bottom 13 is typically also the direction of gravity. The demister 30 is positioned above the flower plate 20, and the first liquid receiving pipe 40 is positioned below the flower plate 20. The drain port 11 can be positioned vertically below the diversion hole 21.

[0053] Optionally, the flower plate 20 is horizontally mounted in the tower body 10, with the horizontal direction being perpendicular to the up-down direction. The horizontal direction includes the front-back and left-right directions that are perpendicular to each other.

[0054] The vertical dimension of the tower body 10 may be greater than the horizontal dimension, and the cross-sectional shape and size of the flower plate 20 and the tower body 10 may be the same, that is, the edge of the flower plate 20 may abut against the inner surface of the side wall 14. The present application does not limit the cross-sectional shape of the flower plate 20 and the tower body 10. For example, the cross-sectional shape of the flower plate 20 and the tower body 10 may be circular, elliptical, triangular, quadrilateral, pentagonal, polygonal or other irregular shapes. For ease of explanation, as shown in FIG. Figure 2 and Figure 3 In the illustrated embodiment, the cross-sections of the flower plate 20 and the tower body 10 at the height where the flower plate 20 is located are both circular.

[0055] Optionally, the cross-sectional shape and cross-sectional size of the tower body 10 may be different at different positions from top to bottom, and the side wall 14 of the tower body 10 may be formed with a folded corner or a curved edge.

[0056] Optionally, in the vertical direction, the distance between the flower plate 20 and the tower top 12 is smaller than the distance between the flower plate 20 and the tower bottom 13. After entering the tower body 10, the smelting acid production flue gas first flows between the flower plate 20 and the tower top 12, flows through the flue gas channel 32 of the demister 30, and then enters the area between the flower plate 20 and the tower bottom 13. This arrangement can remove nitrogen oxides as early as possible at the front end of the acid production process using the smelting acid production flue gas, thereby reducing nitrates in the finished acid.

[0057] See also Figure 1 and Figure 2 In some embodiments, the drain port 11 is formed on the side wall 14, and the first liquid receiving pipe 40 includes a first pipe segment 41 and a second pipe segment 42. The first pipe segment 41 is connected to the flower plate 20 and communicates with the guide hole 21, and the second pipe segment 42 is connected to the side wall 14 and communicates with the drain port 11. At least a portion of the first pipe segment 41 forms an angle with the second pipe segment 42.

[0058] In this way, the first pipe section 41 is connected to the guide hole 21 on the flower plate 20, and the second pipe section 42 is connected to the drain port 11 on the side wall 14. At least part of the first pipe section 41 forms an angle with the second pipe section 42, thereby forming a curved drainage route to adapt to the arrangement of components inside the tower body 10.

[0059] Specifically, the two sides of the flower plate 20 in the thickness direction face the tower top 12 and the tower bottom 13, respectively. The diversion holes 21 are through-holes that extend vertically through the flower plate 20. The drainage port 11 is formed on the side wall 14 below the flower plate 20. The drainage port 11 is also a through-hole, and the direction in which the drainage port 11 penetrates the side wall 14 forms an angle with the vertical direction. For example, the drainage port 11 can be formed on the left side wall 14 of the tower body 10, extending from left to right through the side wall 14.

[0060] One end of the first pipe section 41 is connected to the diversion hole 21, and the other end is connected to the second pipe section 42. In the vertical direction, the connection point between the first and second pipe sections 41 and 42 is lower than that of the diversion hole 21. The end of the second pipe section 42, distal from the first pipe section 41, can be connected to the drain port 11 for connection, or it can extend partially outside the tower body 10 through the liquid receiving port. At least a portion of the first pipe section 41 forms an angle with the second pipe section 42, thereby connecting the diversion hole 21 and the drain port 11 in opposite directions.

[0061] Optionally, the first pipe section 41 and the second pipe section 42 may be rigid or flexible pipes. For example, the first pipe section 41 and the second pipe section 42 are both rigid pipes. The first pipe section 41 is a straight pipe extending linearly downward from the diversion hole 21 to the height of the drainage port 11. The second pipe section 42 is also a straight pipe extending horizontally from the drainage port 11 to below the diversion hole 21 and communicating with the first pipe section 41.

[0062] Optionally, the first pipe section 41 extends along a curved path to connect the guide holes 21 distributed at different horizontal positions on the flower plate 20 with the second pipe section 42 .

[0063] See also Figure 1-Figure 3 In some embodiments, there are multiple first pipe segments 41 , and the multiple first pipe segments 41 are connected to the guide holes 21 in a one-to-one correspondence, and the multiple first pipe segments 41 converge into the second pipe segment 42 .

[0064] In this way, multiple first pipe sections 41 are connected to the guide holes 21 in a one-to-one correspondence, and multiple first pipe sections 41 converge into the second pipe section 42, so that the ammonium sulfate droplets collected by the multiple guide holes 21 converge in the second pipe section 42 and are discharged. When the nitrate is discharged, the liquid flow rate is large, which is convenient for self-flow and not easy to crystallize, and the drainage effect is better.

[0065] Specifically, the number of first pipe segments 41 is the same as the number of diversion holes 21, and each first pipe segment 41 is connected to one diversion hole 21. The number of first pipe segments 41 and diversion holes 21 can be two, three, four, six, nine, ten, or more. The number of second pipe segments 42 can be one, and the ends of multiple first pipe segments 41 away from the diversion holes 21 are all connected to the second pipe segment 42.

[0066] Exemplarily, the number of the guide holes 21 is four, and the four guide holes 21 are arranged near the center of the flower plate 20. The four guide holes 21 are arranged at intervals from each other. The number of the first pipe sections 41 is also four. The four first pipe sections 41 can be arranged to avoid each other and connected to the second pipe section 42 at four different positions of the second pipe section 42.

[0067] Furthermore, two diversion holes 21 may be provided on either side of a line II connecting the vertical projection of the drain port 11 on the flower plate 20 and the center of the flower plate 20. The four diversion holes 21 may be arranged sequentially and spaced apart along the direction of the line II. The diversion holes 21 on either side of the line II may be at the same or different distances from the line II. The vertical projection of the second pipe segment 42 on the flower plate 20 may coincide with the line II.

[0068] The plurality of guide holes 21 may also be arranged in other regular patterns on the flower plate 20, or may be randomly dispersed on the flower plate 20. The plurality of first pipe sections 41 may be spaced apart from each other, or may partially overlap or contact each other.

[0069] See also Figure 1 and Figure 2In some embodiments, the denitrification device 100 includes an installation assembly 50, which includes a plurality of fixing brackets 51 and an interface flange 52. The fixing brackets 51 at least partially cover the tube body of the first liquid receiving pipe 40. The plurality of fixing brackets 51 are arranged at intervals along the extension path of the first liquid receiving pipe 40. The interface flange 52 is arranged at the end of the first liquid receiving pipe 40 that is connected to the drain port 11.

[0070] In this way, the first liquid receiving pipe 40 is installed in the tower body 10 through the installation assembly 50, ensuring that the first liquid receiving pipe 40 is stably connected to the guide hole 21 and the drain port 11, and smoothly guides the ammonium sulfate droplets to be discharged out of the tower body 10.

[0071] Specifically, the fixing bracket 51 may include standard parts such as gaskets, washers, bolts, and nuts, and is fixedly connected to the first liquid receiving pipe 40. Multiple fixing brackets 51 are arranged at intervals along the path of the first liquid receiving pipe 40 to ensure the structural stability of different sections of the first liquid receiving pipe 40.

[0072] Optionally, the end of the second pipe section 42 of the first liquid receiving pipe 40 away from the first pipe section 41 passes through the drain port 11 and partially extends outside the tower body 10. The interface flange 52 is sleeved on the end of the first liquid receiving pipe 40 passing through the drain port 11, so that the end of the first liquid receiving pipe 40 is fixed in the drain port 11.

[0073] See also Figure 1 and Figure 3 In some embodiments, there are multiple demisters 30, and the multiple demisters 30 are arranged at intervals in the horizontal direction on the flower plate 20. A first flue gas channel 321 is formed inside the demister 30, and a second flue gas channel 322 is formed between the outer surfaces of adjacent and opposite demisters 30. The first flue gas channel 321 and the second flue gas channel 322 are connected.

[0074] In this way, by increasing the number of demisters 30, multiple demisters 30 are arranged at intervals on the flower plate 20, thereby increasing the contact area between the demisters 30 and the smelting acid-making flue gas, which is conducive to sufficient denitrification.

[0075] Specifically, the demister 30 is a vertical demister 30, and multiple demisters 30 can be arranged in intervals along the vertical direction and the horizontal direction on the flower plate 20. The demister 30 can be a hollow structure, and the hollow space inside the demister 30 and the space between adjacent demisters 30 can form a flue gas channel 32. The hollow space inside the demister 30 forms a first flue gas channel 321, and the space between adjacent demisters 30 forms a second flue gas channel 322.

[0076] In this embodiment, ammonium sulfate droplets can form on both the inner and outer surfaces of the demister 30. The contact area between the second flue gas channel 322 and the demister 30 is obviously larger than the contact area between the first flue gas channel 321 and the demister 30, and the ammonium sulfate droplets mainly form on the outer surface of the demister 30.

[0077] In some embodiments, the demister 30 is configured such that the surface temperature of the demister 30 is greater than 65° C. and less than 90° C. under operating conditions.

[0078] In this way, by keeping the surface temperature of the demister 30 within a reasonable range under the operating conditions, the formation of nitrogen oxides into crystals on the surface of the demister 30 can be reduced or even avoided.

[0079] As described above, the spray assembly 16 sprays concentrated sulfuric acid below the flower plate 20. The temperature of the sprayed acid liquid is usually 72°C to 75°C. The nitrogen oxides in the smelting acid-making flue gas combine with SO2 and SO3 in the acid mist to form ammonium sulfate. The smelting acid-making flue gas carries the ammonium sulfate in the form of acid mist and passes upward into the flue gas channel 32, contacting the surface of the demister 30.

[0080] Specifically, the surface temperature of the demister 30 is slightly lower than the acid mist temperature, which facilitates droplet condensation. However, when the surface temperature of the demister 30 is low, the solubility of ammonium sulfate decreases, and the droplets are more likely to precipitate solid crystals. Therefore, the demister 30 must be maintained at a temperature greater than 65°C during operation. When operating conditions fluctuate, the acid mist temperature rises, and the fluctuating demister surface temperature also increases. When the surface temperature of the demister 30 or the acid mist temperature exceeds 90°C, the acid mist can severely corrode the equipment. Therefore, keeping the demister 30 surface temperature below 90°C helps extend its service life.

[0081] For example, the surface temperature of the demister 30 may be 65° C. to 69° C., 70° C. to 72° C., 73° C. to 85° C., 78° C. to 86° C., 80° C. to 88° C., etc.

[0082] See also Figure 3 and Figure 5 In some embodiments, the guide hole 21 is set on the flower plate 20 to avoid the demister 30. The demister 30 is a hollow cylindrical structure. A guide channel 311 is formed in the cylindrical wall 31 of the demister 30. The guide channel 311 is used to guide the droplets condensed on the inner wall of the demister 30 to flow to the outer wall of the demister 30.

[0083] In this way, the demister 30 is a hollow cylindrical structure, and the smelting acid-making flue gas can flow inside and outside the cylinder wall 31. The guide hole 21 is set on the flower plate 20 away from the demister 30, so that the guide hole 21 is connected to the flue gas channel 32 formed on the outer wall of the demister 30, and the droplets condensed on the inner wall are guided to the outer wall of the demister 30 through the guide channel 311, so that the guide hole 21 and the first liquid receiving pipe 40 can collect and discharge the ammonium sulfate droplets formed inside and outside the demister cylinder together.

[0084] Specifically, the cross-sectional shape of the demister 30 includes, but is not limited to, a circle, a triangle, a pentagon, a hexagon, or other irregular shapes. For example, the demister 30 is a hollow cylinder with two ends connected.

[0085] The hollow area inside the demister 30 forms a first flue gas channel 321, and the unoccupied area inside the tower body 10 and outside the wall of the demister 30 forms a second flue gas channel 322. In this embodiment, the flower plate 20 is provided with a mounting hole 22 and a hollow base 23 that interfaces with the mounting hole 22. The demister 30 is mounted on the hollow base 23, and the hollow base 23 and the interior of the demister 30 are connected. The smelting acid flue gas passes from bottom to top through the mounting hole 22, the hollow base 23, and the first flue gas channel 321, and then enters the second flue gas channel 322 through the opening at the upper end of the demister 30. When the demister 30 is in operation, nitrate droplets can form on both the inner and outer surfaces of the demister 30.

[0086] The flow guide channel 311 may be a small pipe connecting the inner and outer surfaces of the demister 30 , or may be a fine channel formed by a cavity, a hole, or the like.

[0087] Optionally, a plurality of demisters 30 and guide holes 21 are provided on the flower plate 20, and a second flue gas channel 322 is formed between adjacent demisters 30. The guide holes 21 are arranged away from the demisters 30 and are connected to the second flue gas channel 322 to receive ammonium sulfate droplets flowing from the outer surface of the demister 30 to the flower plate 20.

[0088] See also Figure 5 , Figure 5 The middle arrow indicates the approximate flow direction of the ammonium sulfate droplets. In some embodiments, the wall 31 of the demister 30 includes a fiber layer 312 and a wire mesh layer 313. Both the fiber layer 312 and the wire mesh layer 313 have porous structures, and the mesh of the fiber layer 312 is finer than that of the wire mesh layer 313. The wire mesh layer 313 is disposed outside the fiber layer 312, and the fiber layer 312 and the wire mesh layer 313 together form a flow guide channel 311.

[0089] In this way, the fiber layer 312 and the wire mesh layer 313 are both porous structures, and the mesh holes of the fiber layer 312 are finer than those of the wire mesh layer 313. The wire mesh layer 313 is arranged outside the fiber layer 312, and the fiber layer 312 and the wire mesh layer 313 jointly form a guide channel 311, so that the fiber layer 312 can easily collect droplets formed on the inner wall of the demister 30, and the wire mesh layer 313 continues to discharge the droplets collected by the fiber layer 312 to the outside. The guide channel 311 utilizes the arrangement of the porous structure in the cylinder wall 31 to achieve flow collection and drainage.

[0090] Specifically, the fiber layer 312 and the wire mesh layer 313 are wound into a hollow cylindrical shape, and the fiber layer 312 surrounds the first flue gas channel 321. The demister 30 also includes an inner frame 314 and an outer baffle 315. The inner frame 314 is disposed in the first flue gas channel 321 and is connected to the fiber layer 312. The outer baffle 315 is wrapped around the outside of the wire mesh layer 313. The fiber layer 312, the wire mesh layer 313, and the outer baffle 315 are stacked in sequence from the inside to the outside and can be compacted into the cylinder wall 31 of the demister 30. The inner frame 314 and the outer baffle 315 can support the fiber layer 312 and the wire mesh layer 313. The outer baffle 315 is relatively smooth relative to the wire mesh layer 313, making it easier to condense droplets, which is also conducive to the ammonium sulfate droplets flowing along the outer surface of the outer baffle 315 to the flower plate 20.

[0091] The mesh of the wire mesh layer 313 is coarser and sparser than that of the fiber layer 312. The finer, more porous structure of the fiber layer 312 easily absorbs and collects condensed droplets. The mesh of the wire mesh layer 313 and the fiber layer 312 together form the flow channel 311. Due to the coarser pore size of the wire mesh layer 313, droplets collected by the fiber layer 312 are easily discharged toward the wire mesh layer 313, that is, outward.

[0092] Optionally, the outer baffle 315 and the wire mesh layer 313 may be made of metal.

[0093] See also Figure 6 , combined with Figure 1-Figure 3 In some embodiments, the flower plate 20 is formed with a mounting hole 22 and is provided with a hollow base 23 docking with the mounting hole 22. The demister 30 is a hollow cylindrical structure and is upright on the hollow base 23. The inner wall surface of the hollow base 23 is formed with a collecting groove 231; the denitrification device 100 includes a second liquid receiving pipe 43, which connects the collecting groove 231 with the drain port 11.

[0094] In this way, by setting a collecting groove 231 on the inner wall surface of the hollow base 23, the collecting groove 231 is connected to the second liquid receiving pipe 43, so that the ammonium sulfate droplets formed on the inner surface of the demister 30 can be directly discharged to the outside of the tower body 10 through the second liquid receiving pipe 43.

[0095] Specifically, the hollow base 23 can be a hollow flat cylinder. The hollow base 23 is erected on the flower plate 20. The bottom end of the hollow base 23 is connected to the flower plate 20, and the top end is connected to the demister 30. The demister 30 is a hollow cylindrical structure and is erected on the hollow base 23. The hollow space inside the demister 30 (i.e., Figure 3 The first flue gas channel 321 shown is connected to the hollow base 23.

[0096] The collecting groove 231 is an open groove, and the opening of the collecting groove 231 faces the demister 30 to receive the ammonium sulfate droplets formed on the inner surface of the demister 30. Optionally, the collecting groove 231 surrounds the inner wall surface of the hollow base 23.

[0097] Optionally, the mounting hole 22, hollow base 23, and demister 30 are aligned sequentially from bottom to top, with the cross-sectional shapes and sizes of the three matching each other. For example, the hollow base 23 and demister 30 are both cylindrical, the mounting hole 22 is a circular hole, and the diameters of the hollow base 23 and demister 30 are the same as or close to the diameter of the mounting hole 22.

[0098] One end of the second liquid receiving pipe 43 extends into the mounting hole 22 and the interior of the hollow base 23, communicating with the manifold 231. The other end communicates with the drain port 11. The discharge end of the second liquid receiving pipe 43 can be directly connected to the drain port 11 or extend outside the drain port 11. Alternatively, it can be connected to the second pipe section 42 of the first liquid receiving pipe 40. This allows the ammonium sulfate droplets collected in the manifold 231 and the diversion holes 21 to be discharged from the same drain port 11, streamlining the piping.

[0099] Optionally, to ensure adequate denitrification, multiple demisters 30 are installed on the flower plate 20. Each demister 30 is supported and held upright by a hollow base 23. The inner wall of each hollow base 23 is provided with at least one manifold 231. Accordingly, the number of second liquid receiving pipes 43 matches the number of manifolds 231. The multiple second liquid receiving pipes 43 can converge into a single pipe section before connecting to the drain port 11.

[0100] See also Figure 7 In some embodiments, the denitrification device 100 includes a drainage trough 60 and a first pipeline 71. The first pipeline 71 connects the drainage port 11 with the drainage trough 60. The drainage trough 60 is used to accumulate ammonium sulfate solution.

[0101] In this way, the drain port 11 is connected to the drain trough 60 through the first pipeline 71, so that the ammonium sulfate droplets are discharged into the drain trough 60. The ammonium sulfate droplets are enriched in the drain trough 60 and accumulate to form an ammonium sulfate solution, which is convenient for centralized discharge and post-processing.

[0102] Specifically, the drainage trough 60 can be a tank, a groove, or other liquid container. The first conduit 71 is connected to the drainage port 11. This can be done by connecting the end of the first liquid receiving pipe 40 to the drainage port 11, with the head end of the first conduit 71 connecting to and connecting with the drainage port 11 on the other side of the drainage port 11. Alternatively, if the end of the first liquid receiving pipe 40 partially extends through the drainage port 11 and out of the tower body 10, the head end of the first conduit 71 is directly connected to the end of the first liquid receiving pipe 40. The end of the first conduit 71 is connected to the drainage trough 60 and can be positioned lower than the head end of the first conduit 71 to utilize gravity to transport the ammonium sulfate droplets.

[0103] See also Figure 7 In some embodiments, the denitrification device 100 includes a second pipeline 72 and a post-processing mechanism 80. The second pipeline 72 is provided with a delivery pump 61. The drainage tank 60 and the post-processing mechanism 80 are connected through the second pipeline 72. The post-processing mechanism 80 is used to harmlessly treat the ammonium sulfate solution.

[0104] In this way, the second pipeline 72 and the delivery pump 61 discharge the ammonium sulfate solution in the drainage tank 60 to the post-processing mechanism 80, so that the ammonium sulfate solution is harmlessly treated, thereby achieving the purpose of environmental protection.

[0105] Specifically, the post-processing mechanism 80 may be set up at a remote factory site to reduce the risk of chemical contamination. Accordingly, the second pipeline 72 is a longer pipeline system to achieve long-distance transportation.

[0106] Optionally, the drainage trough 60 is provided with a liquid level meter 62, which counts the liquid level or volume of the ammonium sulfate solution accumulated in the drainage trough 60, so that the drainage trough 60 can control whether to discharge the ammonium sulfate solution into the second pipeline 72 according to the liquid level or volume of the ammonium sulfate solution.

[0107] See also Figure 7 In some embodiments, the drainage trough 60 and / or the first pipeline 71 and / or the second pipeline 72 are provided with a heat preservation mechanism 90, and the heat preservation mechanism 90 is used to keep the drainage trough 60 and / or the first pipeline 71 and / or the second pipeline 72 warm.

[0108] In this way, the drainage trough 60 and / or the first pipeline 71 and / or the second pipeline 72 are heated by the insulation mechanism 90, so that the ammonium sulfate solution is not easy to crystallize in the transportation facilities such as the drainage trough 60, the first pipeline 71, the second pipeline 72 after being discharged from the tower body 10, thereby ensuring that the denitrification by-products can be discharged and post-processed smoothly, and at the same time improving the service life of the transportation facilities such as the drainage trough 60, the first pipeline 71, the second pipeline 72.

[0109] Optionally, the heat preservation mechanism 90 is provided in the drainage tank 60, the first pipeline 71 and the second pipeline 72. The heat preservation mechanism is configured to maintain the heat preservation temperature above 75°C so that crystals are not easily precipitated during the transportation of the ammonium sulfate solution.

[0110] Optionally, the heat preservation mechanism 90 is an electrical appliance with a heating function, which heats and preserves the drain tank 60, the first pipe 71, and the second pipe 72 by means of electric heating or steam heating. The heat preservation mechanism 90 can adjust the heating power according to the ambient temperature.

[0111] In the description of this specification, reference to the terms "one embodiment," "some embodiments," "certain embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any appropriate manner in any one or more embodiments or examples.

[0112] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and intent of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A denitrification device for removing nitrogen oxides from smelting acid flue gas, characterized in that: The denitration device comprises: A tower body, wherein the tower body is provided with a liquid discharge port; A flower plate, the flower plate is mounted in the tower body and has a plurality of diversion holes formed thereon; A demister, the demister being vertically mounted on the flower plate, the demister being formed with a flue gas channel, the flue gas channel being used for circulating the smelting acid-making flue gas, the guide hole being in communication with the flue gas channel; A first liquid receiving pipe is connected with the guide hole and the liquid discharge port.

2. The denitration device according to claim 1, characterized in that: The liquid discharge port is formed on the side wall of the tower body, and the liquid receiving pipe includes a first pipe section and a second pipe section. The first pipe section is connected to the flower plate and communicates with the guide hole, and the second pipe section is connected to the side wall and communicates with the liquid discharge port. At least a portion of the first pipe section forms an angle with the second pipe section.

3. The denitration device according to claim 2, characterized in that: There are multiple first pipe sections, and the multiple first pipe sections are connected to the guide holes in a one-to-one correspondence. The multiple first pipe sections converge into the second pipe section.

4. The denitration device according to claim 1, characterized in that: There are multiple demisters, and the multiple demisters are arranged at intervals in the horizontal direction on the flower plate. A first flue gas channel is formed inside the demister, and a second flue gas channel is formed between the adjacent and opposite outer surfaces of the demisters. The first flue gas channel and the second flue gas channel are connected.

5. The denitration device according to claim 1, characterized in that: The guide hole is arranged on the flower plate to avoid the demister. The demister is a hollow cylindrical structure. A guide channel is formed in the cylinder wall of the demister. The guide channel is used to guide the droplets condensed on the inner wall of the demister to flow to the outer wall of the demister.

6. The denitration device according to claim 5, characterized in that: The cylinder wall of the demister includes a fiber layer and a wire mesh layer. Both the fiber layer and the wire mesh layer are porous structures, and the mesh holes of the fiber layer are finer than those of the wire mesh layer. The wire mesh layer is arranged outside the fiber layer, and the fiber layer and the wire mesh layer together form the guide channel.

7. The denitration device according to claim 1, characterized in that: The flower plate is formed with a mounting hole and is provided with a hollow base docking with the mounting hole. The demister is a hollow cylindrical structure and is vertically arranged on the hollow base. The inner wall surface of the hollow base is formed with a collecting groove. The denitration device includes a second liquid receiving pipe, and the second liquid receiving pipe is connected with the collecting tank and the liquid discharge port.

8. The denitration device according to claim 1, characterized in that: The denitrification device includes a drainage trough and a first pipeline. The first pipeline connects the drainage port and the drainage trough. The drainage trough is used to accumulate ammonium sulfate solution.

9. The denitration device according to claim 8, characterized in that: The denitrification device includes a second pipeline and a post-processing mechanism. The second pipeline is provided with a delivery pump. The drainage tank and the post-processing mechanism are connected through the second pipeline fluid path. The post-processing mechanism is used for harmlessly treating the ammonium sulfate solution.

10. The denitration device according to claim 9, characterized in that: The drainage trough and / or the first pipeline and / or the second pipeline are provided with a heat preservation mechanism, and the heat preservation mechanism is used to keep the drainage trough and / or the first pipeline and / or the second pipeline warm.

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