Aluminum fluoride tail gas desulfurization and denitration system and denitration method

Abstract

The application discloses a fluorinated aluminum tail gas desulfurization and denitration system, which effectively realizes the purpose of more uniform waste water scattering process, and comprises a feeding module, a drying tower, an air heating module, a primary cyclone separator, a secondary cyclone separator and a waste gas treatment module; the drying tower comprises a tower body, a hot air distributor, an atomizer, an observation manhole, a tower inner illumination module and a pneumatic knocking hammer; the lower side of the atomizer is provided with a scattering frame; the fluorinated aluminum tail gas denitration method comprises the following steps: step S1, waste water feeding; step S2, waste water atomization; step S3, waste water micro-droplet solidification; and step S4, drying tail gas treatment in the tower body; the application has the advantages of novel structure, ingenious design, simple and convenient operation, effective collection of dried solid particles, increased atomization effect of waste liquid during atomization, adaptability to different atomization liquid feeding amounts and the function of atomization effect adjustment during atomization.

Description

Technical Field

[0001] This invention belongs to the field of chemical production technology and relates to a desulfurization and denitrification system and method for aluminum fluoride tail gas. Background Technology

[0002] In existing technologies, aluminum fluoride is typically prepared by reacting hydrogen fluoride gas generated from the reaction of fluorite and sulfuric acid with aluminum hydroxide in a fluidized bed. However, the preparation of aluminum fluoride generates tail gas, the main components of which are moisture, H2SO4 acid mist, small amounts of SO2, and particulate matter. This tail gas is generally desulfurized using a dual-alkali method, during which NOx is simultaneously removed from the tail gas, forming nitrates and nitrites in the desulfurization circulating liquid. However, nitrates are readily soluble in water and are not easily converted into precipitates for removal. With long-term circulation and absorption, when the concentration reaches saturation, it will no longer be able to absorb NOx, significantly impacting the NOx absorption efficiency.

[0003] A patent application with application number CN201720325372.0 was found, disclosing a spray drying tower, including a tower body, a discharge device, and a feed device. Both the discharge device and the feed device are connected to the tower body. The tower also includes an air filter and a chiller, which are sequentially connected via a first pipe. This spray drying tower, by adding a chiller and an air filter, reduces the probability of material agglomeration, improves production efficiency, reduces losses, and shortens the production cycle. An atomizer is installed to atomize the air, allowing for quick drying of the liquid material into powder. An electric hoist is used to lift the atomizer, facilitating maintenance and cleaning of the atomizing disc. A hot air inlet fan is installed to draw heated air into the tower via a distributor. A steam heating device and electric heating wires are also included to heat the air before it enters the tower to dry the liquid material.

[0004] Additionally, a patent application with application number CN201420845996.1 was found, disclosing an energy-saving spray drying system, including a drying tower and a cyclone separator. The drying tower is equipped with a high-speed atomizer connected to the feed inlet. The system is characterized by: a hot air distributor and a purge pipe; the hot air distributor connects to a heater and an air inlet; the purge pipe connects to a high-pressure air inlet; one side of the cyclone separator is connected to the conical bottom of the drying tower, and the other side is connected to a bag filter; both the cyclone separator and the bag filter are equipped with a recovery fan connected to the hot air distributor; and an air dehumidifier is also provided between the recovery fan and the hot air distributor. This utility model combines a cyclone separator and a bag filter with a drying tower, enabling thorough drying and further upgrading product quality to meet the needs of high-end users. Furthermore, the inclusion of a recovery fan connected to the hot air distributor in both the cyclone separator and the bag filter contributes to energy conservation, environmental protection, and effective cost control.

[0005] However, the above patent documents all have shortcomings in the atomization stage of waste liquid. During the wastewater treatment process, the concentration of internal impurities will change to a certain extent, which will affect the viscosity of the wastewater and thus affect the atomization effect. During the hot air drying process, it will affect the drying efficiency. Therefore, a desulfurization and denitrification system and denitrification method for aluminum fluoride tail gas that can maintain stable atomization efficiency is needed to solve the above problems. Summary of the Invention

[0006] To address the above problems, this invention proposes an aluminum fluoride tail gas desulfurization and denitrification system and method, which effectively solves the problems in the prior art.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] An aluminum fluoride tail gas desulfurization and denitrification system includes:

[0009] The feeding module is used to transport the wastewater to be dried;

[0010] A drying tower is used to atomize and dry wastewater, so that the solid solutions in the wastewater are dried into powder. It includes a tower body, a hot air distributor, an atomizer, an observation manhole, an internal lighting module, and a pneumatic hammer. The hot air distributor is connected to the top of the tower body. The atomizer is located on the upper side inside the tower body. The upper side of the atomizer is connected to the feeding module. A disintegrating frame that can rotate with the atomizer is provided on the lower side of the atomizer.

[0011] An air heating module, connected to the hot air distributor, is used to deliver dry hot air into the drying tower;

[0012] A primary cyclone separator and a secondary cyclone separator are provided. The primary cyclone separator is connected to the bottom of the drying tower, and the feed end of the secondary cyclone separator is connected to the air outlet end of the primary cyclone separator.

[0013] The exhaust gas treatment module includes a water spray device and a spray pool.

[0014] Preferably, the tower body includes a top plate, a circular cylinder and a conical cylinder from top to bottom. The atomizer is located on the lower side of the top plate, and a cleaning port is provided on the lower side of the conical cylinder. The pneumatic hammer is installed at the connection between the circular cylinder and the conical cylinder. The observation manhole and the tower lighting module are both located on the circular cylinder.

[0015] Preferably, the atomizer includes a rotatable atomizing disc and an adjusting frame that can move up and down along the atomizing disc. A plurality of first guide strips are fixedly connected to the lower side of the atomizing disc, and a plurality of second guide strips are fixedly connected to the lower side of the adjusting frame. The first guide strips and the second guide strips cooperate with each other to form a structure for dispersing wastewater droplets.

[0016] Preferably, a rotating frame is rotatably connected to the outer side of the atomizing disc, and the adjusting frame is threaded onto the outer side of the rotating frame, so that the rotating frame rotates to form a structure for the adjusting frame to rise and fall.

[0017] Preferably, the upper side of the atomizing disc is connected to a feeding sleeve, the top of the feeding sleeve is fixedly connected to a first bevel gear ring, the upper side of the first bevel gear ring is engaged with a first bevel gear rotatably connected to the top plate, and a power motor is provided on the front side of the first bevel gear, the output end of the power motor is fixedly connected to the first bevel gear.

[0018] Preferably, a sun gear is fixedly connected to the upper side of the atomizing disc, an external gear ring is fixedly connected to the inner side of the rotating frame, multiple planetary gears mesh between the sun gear and the external gear ring, a planet carrier is rotatably connected to the upper side of the sun gear, and the upper side of each planetary gear is rotatably connected to the planet carrier.

[0019] Preferably, a third bevel gear ring is fixedly connected to the upper side of the planetary carrier, and a second bevel gear and a third bevel gear are meshed on the upper side of the third bevel gear. An adjusting motor is fixedly connected to the unloading sleeve on the rear side of the second bevel gear, and the output end of the adjusting motor is fixedly connected to the second bevel gear. A counterweight is provided on the front side of the third bevel gear, and the front side of the counterweight is rotatably connected to the unloading sleeve.

[0020] Preferably, a large turntable is fixedly connected to the upper side of the atomizing sleeve, and a power ring that is rotatably connected to the top plate is fixedly connected to the upper side of the disintegrating frame. A connecting rod that can move up and down is provided between the power ring and the large turntable. A rotating disk is provided on the outer side of the connecting rod through a sliding sleeve. Two fixed plates that are fixedly connected to the connecting rod are provided on the lower side of the rotating disk. A tension spring is provided on the upper side of each fixed plate, and the upper side of each tension spring is fixedly connected to the fixed plate. The large turntable, the rotating disk, and the power ring cooperate with each other to form a structure in which the disintegrating frame rotates together with the atomizing disk. A connecting block is rotatably connected to the upper side of the connecting rod, and an electric telescopic rod is provided on the upper side of the connecting block.

[0021] Preferably, the disassembly frame includes multiple first disassembly plates whose bottoms are fixedly connected to each other, and multiple second disassembly plates are provided between every two adjacent first disassembly plates.

[0022] This invention also discloses a method for denitrifying aluminum fluoride tail gas, comprising the following steps:

[0023] Step S1: Wastewater feeding. High-concentration saline wastewater in the circulating water tank of the desulfurization and denitrification unit is pumped to the inlet water tank of the drying and reuse unit for temporary storage by a screw pump, and then pumped into the high-level tank of the drying tower. The screw pump adopts frequency conversion speed regulation, which can effectively control the feed rate.

[0024] Step S2: Wastewater atomization. Under the action of gravity, the wastewater in the high-level tank of the drying tower flows naturally from the high-level tank into the center of the atomizer inside the tower body through the water outlet pipe. The atomizer drives the wastewater droplets to rotate at a high speed of 11600r / min, which accelerates the wastewater droplets and makes the wastewater droplets obtain a very high tangential linear velocity. When the wastewater droplets leave the atomizer, they are immediately rubbed and torn by air, and atomized into wastewater micro-droplets.

[0025] When the atomizer is started, the dispersing frame can be rotated in the opposite direction of the atomizer to further disperse larger wastewater droplets.

[0026] Step S3: Solidification of wastewater droplets. Hot air discharged from the air heating module is sent into the hot air distribution chamber located at the top of the tower through the hot air duct. It comes into contact with the wastewater droplets in a co-current manner, drying the solid solution in the wastewater into powder, which falls to the lower part of the tower.

[0027] Step S4: Treatment of drying exhaust gas in the tower body. The drying exhaust gas is discharged after passing through the exhaust port located at the bottom of the tower body in sequence through the first-stage cyclone separator and the second-stage cyclone separator to recover fine powder. The exhaust gas discharged from the second cyclone separator is then treated by the water spray device and discharged through a 30m high exhaust stack. The water vapor in the drying exhaust gas is condensed and enters the circulating water pool of the water spray device, and then pumped into the circulating water pool of the desulfurization and denitrification device for reuse.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. The present invention has an atomizer that can adjust the atomization effect, which can better atomize wastewater and adapt to different wastewater viscosities, thereby improving the stability of atomization.

[0030] 2. This invention has a primary cyclone separator and a secondary cyclone separator. Through the two-stage cyclone separator, fine powder can be recovered, thereby enabling more thorough material recovery and increasing the recovery rate.

[0031] 3. The present invention has a first guide strip and a second guide strip, which can guide the droplets thrown out from around the atomizing plate. That is, through the action of the first guide strip and the second guide strip, the contact area of ​​the droplets when they leave the atomizing plate is reduced, thereby reducing the size of the droplets thrown out. When the liquid inlet of the atomizer is small, the droplets can be guided by the first guide strip alone. When the liquid inlet increases, the second guide strip can be extended from the bottom of the atomizing plate to improve the guiding efficiency. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the overall structure of the denitrification system in this invention.

[0033] Figure 2 This is a schematic diagram of the tower structure in this invention.

[0034] Figure 3 This is a schematic diagram showing the position of the power motor in this invention.

[0035] Figure 4 This is a schematic diagram showing the position of the tension spring in this invention.

[0036] Figure 5 This is a schematic diagram of the disassembled frame structure in this invention.

[0037] Figure 6 This is a schematic diagram of the planetary carrier structure in this invention.

[0038] Figure 7 This is an exploded structural diagram of the atomizing disc and the adjustment frame in this invention.

[0039] In the diagram: 1. Feeding module; 2. Tower body; 3. Hot air distributor; 4. Atomizer; 5. Manhole; 6. Disintegration frame; 7. Air heating module; 8. Primary cyclone separator; 9. Secondary cyclone separator; 10. Exhaust gas treatment module; 11. Top plate; 12. Circular cylinder; 13. Conical cylinder; 14. Cleaning port; 15. Atomizing disc; 16. Adjusting frame; 17. First guide bar; 18. Second guide bar; 19. Rotating frame; 20. Discharge sleeve; 21. First conical tooth ring ; 22. First bevel gear; 23. Power motor; 24. Sun gear; 25. External gear ring; 26. Planetary gear; 27. Planetary carrier; 28. Third bevel gear ring; 29. ​​Second bevel gear; 30. Third bevel gear; 31. Adjusting motor; 32. Counterweight; 33. Large turntable; 34. Power ring; 35. Connecting rod; 36. Rotating disk; 37. Fixed plate; 38. Tension spring; 39. Connecting block; 40. Electric telescopic rod; 41. First disintegration plate; 42. Second disintegration plate. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] The following is in conjunction with the appendix Figure 1 - Figure 7 The specific embodiments of the present invention will be described in further detail below.

[0042] Depend on Figure 1 - Figure 7 The present invention provides an aluminum fluoride tail gas desulfurization and denitrification system. To achieve a more uniform dispersion process for wastewater, the invention includes:

[0043] Feeding module 1 is used to transport the wastewater to be dried; it pumps the high-concentration saline wastewater in the circulating water pool of the desulfurization and denitrification unit to the inlet water pool of the drying and reuse unit for temporary storage, and then pumps it into the high-level tank of the drying tower. The screw pump adopts frequency conversion speed regulation, which can effectively control the feed rate.

[0044] A drying tower is used to atomize and dry wastewater, so that the solid solutions in the wastewater are dried into powder. It includes a tower body 2, a hot air distributor 3, an atomizer 4, an observation manhole 5, an internal lighting module, and a pneumatic hammer. The hot air distributor 3 is connected to the top of the tower body 2. The atomizer 4 is located on the upper side inside the tower body 2. The upper side of the atomizer 4 is connected to the feeding module 1. A disintegrating frame 6 that can rotate with the atomizer 4 is provided on the lower side of the atomizer 4.

[0045] It should be noted that the principle of atomizer 4 is a centrifugal disc atomizer 4. Atomizer 4 is installed in the upper part of the tower body 2. The high-concentration saline wastewater from desulfurization and denitrification in the high-level tank flows naturally from the high-level tank into the center of the centrifugal disc atomizer 4 inside the tower through the outlet pipe under the action of gravity. The centrifugal disc rotates at a high speed of 11600 r / min driven by a motor. When the wastewater flows towards the edge through the channels or nozzles on the centrifugal disc, it gains a very high tangential linear velocity. Once it leaves the atomizer 4, it is immediately atomized into microdroplets by air friction and tearing. When the wastewater contains different impurities, it will affect the viscosity of the wastewater, and thus affect the size of the atomized droplets. When the atomization effect is poor, the dispersing frame 6 can be activated. The dispersing frame 6 rotates in the opposite direction to the atomizer 4, which can mechanically disperse larger atomized droplets, thus ensuring the atomization effect when the viscosity of the wastewater increases.

[0046] The air heating module 7 is connected to the hot air distributor 3 and is used to deliver dry hot air into the drying tower.

[0047] It should be noted that the air heating module 7 consists of a primary air filter, a medium-efficiency air filter, a fan, and a heater. The heat source is the indirect heating tail gas from the jacket of the hydrogen fluoride reaction kiln in the project, with a temperature of 260℃±10℃ and a heat volume of 25000m3 / h-27000m3 / h. The hot air discharged from the air heating module 7 is sent to the hot air distribution chamber located at the top of the tower 2 through the hot air duct. It contacts the atomized wastewater droplets in a co-current manner, drying the solid solutions in the wastewater into powder, which falls to the lower part of the tower 2.

[0048] A primary cyclone separator 8 and a secondary cyclone separator 9 are provided. The primary cyclone separator 8 is connected to the bottom of the drying tower, and the feed end of the secondary cyclone separator 9 is connected to the air outlet end of the primary cyclone separator 8.

[0049] The exhaust gas treatment module 10 includes a water spray device and a spray water tank;

[0050] It should be noted that the dry exhaust gas discharged from tower body 2 is processed by two-stage cyclone separators, namely primary cyclone separator 8 and secondary cyclone separator 9, to recover fine powder. The exhaust gas is then treated by a water spray device and discharged through a 30m high exhaust stack. The water vapor in the dry exhaust gas is condensed and enters the circulating water pool of the water spray device, and then pumped into the circulating water pool of the desulfurization and denitrification device for reuse.

[0051] Furthermore, by Figure 1 - Figure 7 As provided, in order to facilitate the collection of dried solid particles, the tower body 2 includes, from top to bottom, a top plate 11, a circular cylinder 12, and a conical cylinder 13. The atomizer 4 is located on the lower side of the top plate 11, and a cleaning port 14 is provided on the lower side of the conical cylinder 13. The pneumatic hammer is installed at the connection between the circular cylinder 12 and the conical cylinder 13. The observation manhole 5 and the tower lighting module are both located on the circular cylinder 12.

[0052] When in use, when the solids in the wastewater dry into powder and fall into the conical cylinder 13 at the bottom of the tower body 2, the powder can be collected through the cleaning port 14. In addition, when too much material accumulates on the inner walls of the cylindrical cylinder 12 and the conical cylinder 13, the pneumatic hammer can be activated to remove the material from the side walls.

[0053] Furthermore, by Figure 1 - Figure 7 To enhance the atomization effect of waste liquid during atomization, the atomizer 4 includes a rotatable atomizing disk 15 and an adjusting frame 16 that can move up and down along the atomizing disk 15. The atomizing disk 15 is in the shape of an inverted U-shape. Multiple first guide strips 17 are fixedly connected to the lower side of the atomizing disk 15, and multiple second guide strips 18 are fixedly connected to the lower side of the adjusting frame 16. The first guide strips 17 and the second guide strips 18 cooperate with each other to form a structure for dispersing wastewater droplets.

[0054] In use, the first guide bar 17 and the second guide bar 18 can guide the droplets thrown out from around the atomizing plate 15. That is, through the action of the first guide bar 17 and the second guide bar 18, the contact area of ​​the droplets when they leave the atomizing plate 15 is reduced, thereby reducing the size of the droplets thrown out. When the liquid inlet of the atomizer 4 is small, the droplets can be guided by the first guide bar 17. When the liquid inlet increases, the adjusting frame 16 can be moved down. At this time, the second guide bar 18 extends from the bottom of the atomizing plate 15 to improve the guiding efficiency.

[0055] Furthermore, by Figure 1 - Figure 7 As shown, in order to adapt to different atomization liquid inlet volumes, a rotating frame 19 is rotatably connected to the outer side of the atomizing disk 15, and an adjusting frame 16 is threadedly fitted onto the outer side of the rotating frame 19. The rotating frame 19 rotates to form a structure in which the adjusting frame 16 rises and falls.

[0056] Furthermore, by Figure 1 - Figure 7 To facilitate atomization, a feeding sleeve 20 is connected to the upper side of the atomizing disc 15. A first bevel gear ring 21 is fixedly connected to the top of the feeding sleeve 20. A first bevel gear 22, which is rotatably connected to the top plate 11, is meshed on the upper side of the first bevel gear 21. A power motor 23 is provided on the front side of the first bevel gear 22. The power motor 23 is a servo motor, which is existing technology and will not be described in detail here. The output end of the power motor 23 is fixedly connected to the first bevel gear 22.

[0057] When in use, after starting the power motor 23, the power motor 23 drives the first bevel gear ring 21 to rotate through the first bevel gear 22, and then drives the atomizing disc 15 to rotate through the feeding sleeve 20. It should be understood that the atomizing disc 15 has a feeding hole in the middle that is connected to the feeding sleeve 20. When the liquid is fed in the feeding sleeve 20, the waste liquid enters the bottom of the atomizing disc 15 through the side wall of the feeding sleeve 20.

[0058] Furthermore, by Figure 1 - Figure 7 To enable the second guide strip 18 to extend quickly, a sun gear 24 is fixedly connected to the upper side of the atomizing disc 15, and an external gear ring 25 is fixedly connected to the inner side of the rotating frame 19. Multiple planetary gears 26 mesh together between the sun gear 24 and the external gear ring 25. A planet carrier 27 is rotatably connected to the upper side of the sun gear 24, and the upper side of each planetary gear 26 is rotatably connected to the planet carrier 27.

[0059] During normal atomization, the sun gear 24, planetary gears 26, external gear ring 25, and planetary carrier 27 do not move relative to each other. When it is necessary to rotate the rotating frame 19 relative to the atomizing disc 15, that is, to extend the second guide strip 18, the planetary carrier 27 can be rotated. With the sun gear 24 as the reference frame, the planetary carrier 27 drives the external gear ring 25 to rotate through each planetary gear 26. Due to the meshing of the planetary gears 26 and the sun gear 24, the rotation of the planetary carrier 27 has an accelerating effect relative to the rotation of the external gear ring 25, which enables the rotating frame 19 to rotate quickly and extend the second guide strip 18.

[0060] Furthermore, by Figure 1 - Figure 7To adjust the atomization effect during atomization, a third bevel gear ring 28 is fixedly connected to the upper side of the planetary carrier 27. The upper side of the third bevel gear ring 28 is meshed with a second bevel gear 29 and a third bevel gear 30. An adjustment motor 31 is fixedly connected to the feeding sleeve 20 at the rear side of the second bevel gear 29. The adjustment motor 31 is a servo motor and is equipped with an encoder to monitor the rotation angle of the servo motor. The output end of the adjustment motor 31 is fixedly connected to the second bevel gear 29. A counterweight block 32 is provided at the front side of the third bevel gear 30. The counterweight block 32 is used to adjust the dynamic balance of the adjustment motor 31 to make the rotation of the atomizer 4 more stable. The third bevel gear 30 can make the rotation of the third bevel gear ring 28 relative to the feeding sleeve 20 more stable. The front side of the counterweight block 32 is rotatably connected to the feeding sleeve 20.

[0061] Furthermore, by Figure 1 - Figure 7 To automatically improve the atomization effect, a large turntable 33 is fixedly connected to the upper side of the atomizing sleeve, and a power ring 34 rotatably connected to the top plate 11 is fixedly connected to the upper side of the dispersing frame 6. A connecting rod 35 that can move up and down is provided between the power ring 34 and the large turntable 33. A rotating disk 36 is slidably sleeved on the outer side of the connecting rod 35. Two fixing plates 37 fixedly connected to the connecting rod 35 are provided on the lower side of the rotating disk 36. A tension spring 38 is provided on the upper side of each fixing plate 37. The large turntable 33, the rotating disk 36, and the power ring 34 cooperate with each other to form a structure in which the dispersing frame 6 rotates together with the atomizing disk 15. A connecting block 39 is rotatably connected to the upper side of the connecting rod 35. An electric telescopic rod 40 is provided on the upper side of the connecting block 39.

[0062] It should be noted that the moving end of the electric telescopic rod 40 is equipped with a distance sensor, which is electrically connected to the adjusting motor 31. That is, the extension distance of the electric telescopic rod 40 corresponds one-to-one with the rotation angle of the adjusting motor 31.

[0063] When it is necessary to improve the atomization effect, the electric telescopic rod 40 can be activated to drive the connecting rod 35 downward through the rotating disk 36. As the connecting rod 35 drives the rotating disk 36 to move downward, the rotating disk 36 will contact the outer side of the large rotating disk 33 and the inner side of the power ring 34. As the connecting rod 35 moves further downward, under the action of the rotating disk 36, the rotational power of the large rotating disk 33 is transmitted to the power disk through the rotating disk 36, which in turn drives the dispersing frame 6 to rotate, mechanically dispersing larger droplets. At this time, under the storage action of the tension spring 38, the connecting rod 35 can continue to extend further with the electric telescopic rod 40, making the power transmission more stable. When the electric telescopic rod 40 extends, the adjusting motor 31 will drive the second bevel gear 29 to rotate. At this time, with the feeding sleeve 20 as the reference frame, the second bevel gear 29 drives the third bevel gear ring 28 to rotate relative to the feeding sleeve 20, which in turn drives the planetary carrier 27 to rotate.

[0064] Furthermore, by Figure 1 - Figure 7 In order to achieve a better dispersing effect on wastewater droplets, the dispersing frame 6 includes a plurality of first dispersing plates 41 whose bottoms are fixedly connected to each other, and a plurality of second dispersing plates 42 are provided between every two adjacent first dispersing plates 41.

[0065] In use, the first dispersing plate 41 and the second dispersing plate 42 can improve the dispersing efficiency of the droplets.

[0066] A method for denitrifying aluminum fluoride tail gas includes the following steps:

[0067] Step S1: Wastewater feeding. High-concentration saline wastewater in the circulating water tank of the desulfurization and denitrification unit is pumped to the inlet water tank of the drying and reuse unit for temporary storage by a screw pump, and then pumped into the high-level tank of the drying tower. The screw pump adopts frequency conversion speed regulation, which can effectively control the feed rate.

[0068] Step S2: Wastewater atomization. Under the action of gravity, the wastewater in the high-level tank of the drying tower flows naturally from the high-level tank into the center of the atomizer 4 inside the tower body 2 through the water outlet pipe. The atomizer 4 drives the wastewater droplets to rotate at a high speed of 11600r / min, which accelerates the wastewater droplets and makes the wastewater droplets obtain a very high tangential linear velocity. When the wastewater droplets leave the atomizer 4, they are immediately rubbed and torn by air, and atomized into wastewater micro-droplets.

[0069] When the atomizer 4 is started, the dispersing frame 6 can be rotated in the opposite direction to the atomizer 4 to further disperse larger wastewater droplets.

[0070] Step S3: Solidification of wastewater droplets. Hot air discharged from the air heating module 7 is sent to the hot air distribution chamber located at the top of the tower 2 through the hot air duct. It comes into contact with the wastewater droplets in a co-current manner, drying the solid solution in the wastewater into powder, which falls to the lower part of the tower 2. The heat source of the hot air is the indirect heating tail gas of the hydrogen fluoride reaction kiln jacket, with a temperature of 260℃±10℃ and a hot air volume of 25000m3 / h-27000m3 / h.

[0071] Step S4: Treatment of drying exhaust gas in tower body 2. The drying exhaust gas passes through the exhaust port located at the bottom of tower body 2 in sequence through the first-stage cyclone separator 8 and the second-stage cyclone separator 9 to recover fine powder before being discharged. The exhaust gas discharged from the second cyclone separator is then treated by a water spray device and discharged through a 30m high exhaust stack. The water vapor in the drying exhaust gas is condensed and enters the circulating water pool of the water spray device, and then pumped into the circulating water pool of the desulfurization and denitrification device for reuse.

[0072] This invention features a novel structure, ingenious design, and simple and convenient operation. Through this design, it effectively achieves the goal of more uniformly dispersing wastewater, facilitates the collection of dried solid particles, enhances the atomization effect of waste liquid during atomization, can adapt to different atomization liquid inflow rates, and adds the function of adjusting the atomization effect during the atomization process, making it convenient for operators.

[0073] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A desulfurization and denitrification system for aluminum fluoride tail gas, characterized in that, include: The feeding module (1) is used to transport the wastewater to be dried; A drying tower is used to atomize and dry wastewater, so that the solid solutions in the wastewater are dried into powder. It includes a tower body (2), a hot air distributor (3), an atomizer (4), an observation manhole (5), an internal lighting module, and a pneumatic hammer. The hot air distributor (3) is connected to the top of the tower body (2). The atomizer (4) is located on the upper side inside the tower body (2). The upper side of the atomizer (4) is connected to the feeding module (1). A disintegrating frame (6) that can rotate with the atomizer (4) is provided on the lower side of the atomizer (4). An air heating module (7) is connected to the hot air distributor (3) and is used to deliver dry hot air into the drying tower. A primary cyclone separator (8) and a secondary cyclone separator (9) are provided. The primary cyclone separator (8) is connected to the bottom of the drying tower, and the feed end of the secondary cyclone separator (9) is connected to the air outlet end of the primary cyclone separator (8). The exhaust gas treatment module (10) includes a water spray device and a spray water tank; The atomizer (4) includes a rotatable atomizing disc (15) and an adjusting frame (16) that can move up and down along the atomizing disc (15). A plurality of first guide strips (17) are fixedly connected to the lower side of the atomizing disc (15), and a plurality of second guide strips (18) are fixedly connected to the lower side of the adjusting frame (16). The first guide strips (17) and the second guide strips (18) cooperate with each other to form a structure for dispersing wastewater droplets. A rotating frame (19) is rotatably connected to the outer side of the atomizing disc (15), and the adjusting frame (16) is threadedly fitted onto the outer side of the rotating frame (19). The rotating frame (19) rotates to form a structure in which the adjusting frame (16) rises and falls. The disassembly frame (6) includes multiple first disassembly plates (41) whose bottoms are fixedly connected to each other, and multiple second disassembly plates (42) are provided between every two adjacent first disassembly plates (41).

2. The aluminum fluoride tail gas desulfurization and denitrification system according to claim 1, characterized in that: The tower body (2) includes a top plate (11), a circular cylinder (12) and a conical cylinder (13) from top to bottom. The atomizer (4) is located on the lower side of the top plate (11). A cleaning port (14) is opened on the lower side of the conical cylinder (13). The pneumatic hammer is installed at the connection between the circular cylinder (12) and the conical cylinder (13). The observation manhole (5) and the tower lighting module are both located on the circular cylinder (12).

3. The aluminum fluoride tail gas desulfurization and denitrification system according to claim 2, characterized in that: The upper side of the atomizing disc (15) is connected to a feeding sleeve (20). A first bevel gear ring (21) is fixedly connected to the top of the feeding sleeve (20). A first bevel gear (22) that is rotatably connected to the top plate (11) is engaged on the upper side of the first bevel gear ring (21). A power motor (23) is provided on the front side of the first bevel gear (22). The output end of the power motor (23) is fixedly connected to the first bevel gear (22).

4. The aluminum fluoride tail gas desulfurization and denitrification system according to claim 3, characterized in that: A sun gear (24) is fixedly connected to the upper side of the atomizing disc (15), and an external gear ring (25) is fixedly connected to the inner side of the rotating frame (19). Multiple planetary gears (26) mesh together between the sun gear (24) and the external gear ring (25). A planet carrier (27) is rotatably connected to the upper side of the sun gear (24), and the upper side of each planetary gear (26) is rotatably connected to the planet carrier (27).

5. The aluminum fluoride tail gas desulfurization and denitrification system according to claim 4, characterized in that: A third bevel gear ring (28) is fixedly connected to the upper side of the planetary carrier (27). A second bevel gear (29) and a third bevel gear (30) are meshed on the upper side of the third bevel gear ring (28). An adjusting motor (31) is fixedly connected to the unloading sleeve (20) on the rear side of the second bevel gear (29). The output end of the adjusting motor (31) is fixedly connected to the second bevel gear (29). A counterweight block (32) is provided on the front side of the third bevel gear (30). The front side of the counterweight block (32) is rotatably connected to the unloading sleeve (20).

6. The aluminum fluoride tail gas desulfurization and denitrification system according to claim 5, characterized in that: A large turntable (33) is fixedly connected to the upper side of the atomizing sleeve. A power ring (34) that is rotatably connected to the top plate (11) is fixedly connected to the upper side of the disassembly frame (6). A connecting rod (35) that can move up and down is provided between the power ring (34) and the large turntable (33). A rotating disk (36) is provided on the outer sleeve of the connecting rod (35). Two fixing plates (37) that are fixedly connected to the connecting rod (35) are provided on the lower side of the rotating disk (36). A tension spring (38) is provided on the upper side of each fixing plate (37). The upper side of each tension spring (38) is fixedly connected to the fixing plate (37). The large turntable (33), the rotating disk (36), and the power ring (34) cooperate with each other to form a structure in which the disassembly frame (6) rotates together with the atomizing disk (15). A connecting block (39) is rotatably connected to the upper side of the connecting rod (35). An electric telescopic rod (40) is provided on the upper side of the connecting block (39).

7. A method for denitrifying aluminum fluoride tail gas, applied to an aluminum fluoride tail gas desulfurization and denitrification system according to any one of claims 1-6, characterized in that: Includes the following steps: Step S1: Wastewater feeding. High-concentration saline wastewater in the circulating water tank of the desulfurization and denitrification unit is pumped to the inlet water tank of the drying and reuse unit for temporary storage by a screw pump, and then pumped into the high-level tank of the drying tower. The screw pump adopts frequency conversion speed regulation, which can effectively control the feed rate. Step S2: Wastewater atomization. Under the action of gravity, the wastewater in the high-level tank of the drying tower flows naturally from the high-level tank into the center of the atomizer (4) inside the tower body (2) through the water outlet pipe. The atomizer (4) drives the wastewater droplets to rotate at a high speed of 11600r / min, which accelerates the wastewater droplets and makes the wastewater droplets obtain a very high tangential linear velocity. When the wastewater droplets leave the atomizer (4), they are immediately rubbed and torn by air and atomized into wastewater microdroplets. When the atomizer (4) is started, the dispersing frame (6) can be rotated in the opposite direction to the atomizer (4) to disperse larger wastewater droplets a second time. Step S3: Solidification of wastewater droplets. Hot air discharged from the air heating module (7) is sent through the hot air pipe into the hot air distribution chamber located at the top of the tower (2) and comes into contact with the wastewater droplets in a co-current manner, drying the solid solution in the wastewater into powder, which falls to the lower part of the tower (2). Step S4: Treatment of drying tail gas in tower body (2). The drying tail gas passes through the exhaust port located at the bottom of tower body (2) in sequence through the first-stage cyclone separator (8) and the second-stage cyclone separator (9) to recover fine powder before being discharged. The tail gas discharged from the second cyclone separator is then treated by the water spray device and discharged through a 30m high exhaust stack. The water vapor in the drying tail gas is condensed and enters the circulating water pool of the water spray device, and then pumped into the circulating water pool of the desulfurization and denitrification device for reuse.

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