A multi-stage phosphoric acid spray dryer

Abstract

The present invention relates to the field of spray drying technology, and in particular to a multi-stage phosphoric acid spray dryer comprising a drying tower; a cover plate disposed at the top of the drying tower, a hot air mechanism disposed on the cover plate and the drying tower; a centrifugal spray head and a material retaining mechanism for extending the falling time of the phosphoric acid being rotatably mounted within the drying tower. The present invention utilizes the centrifugal spray head to atomize a phosphoric acid solution and immediately dry the atomized phosphoric acid solution; then, a knocking portion strikes a conical tube to vibrate the conical tube, thereby promoting the falling of phosphoric acid powder and preventing it from adhering to the tube; and then, utilizing centrifugal force, the crushed phosphoric acid powder is ejected for further drying, thereby preventing adhesion and enhancing dehydration, thereby improving drying efficiency and quality.

Description

Technical Field

[0001] The present invention relates to the technical field of spray drying, in particular to a multi-stage phosphoric acid spray dryer. Background Art

[0002] A phosphoric acid spray dryer is a device used to convert liquid phosphoric acid or its solution into dry powder or granules. It is widely used in the chemical, food, and pharmaceutical industries. The operating process of a phosphoric acid spray dryer is as follows: liquid phosphoric acid or its solution is pumped into an atomizer, where a centrifugal atomizer atomizes the liquid phosphoric acid. High-temperature hot air then contacts the atomized droplets within a drying tower, where heat conduction causes the water to evaporate rapidly within seconds. The droplets then dehydrate and solidify to form a dry powder. The dried powder and exhaust gas enter a cyclone separator and bag filter for gas-solid separation and collection.

[0003] However, the above process has the following problems: the liquid phosphoric acid is atomized and spun out for drying only through a centrifugal spray head. The spun out phosphoric acid falls directly to the ground, resulting in the atomized droplets only experiencing a single exposure to high-temperature hot air. Some larger droplets cannot be completely dehydrated in a short period of time, which in turn affects product quality. Secondly, the phosphoric acid spun out by the centrifugal spray head easily adheres to the inner wall of the drying tower, making it difficult for the adhered phosphoric acid to fall off by its own gravity after drying.

[0004] Therefore, the problems of incomplete drying of phosphoric acid and difficulty in falling off the atomized droplets that adhere to the inner wall of the drying tower after drying are technical problems that need to be solved by those skilled in the art. Summary of the Invention

[0005] In view of the above problems, an embodiment of the present invention provides a multi-stage phosphoric acid spray dryer to solve the above-mentioned technical problems.

[0006] To achieve the above-mentioned objectives, an embodiment of the present invention provides the following technical solution: a multi-stage phosphoric acid spray dryer, comprising a drying tower; a cover plate is provided at the upper end of the drying tower, a hot air mechanism is provided on the cover plate and the drying tower, a centrifugal spray head and a material blocking mechanism for extending the falling time of phosphoric acid are rotatably installed in the drying tower; wherein: the material blocking mechanism includes a tapered tube provided at the lower end of the cover plate, a tapered tube and a straight tube are sequentially provided in the drying tower from top to bottom below the centrifugal spray head, a material storage box is rotatably installed at the lower end of the tapered tube, an outer ring wall of the material storage box is uniformly provided with discharge holes along its circumference, a material guide cone is fixedly installed on the inner bottom wall of the material storage box, and a knocking part and a crushing part are provided on the material storage box. A rotating shaft is coaxially fixedly installed on the centrifugal spray head, and the lower end of the rotating shaft is fixedly passed through the material guide cone and the material storage box; the knocking part includes hammers uniformly arranged along the circumference of the upper end of the material storage box, and the hammers are also staggered with the axial direction of the rotating shaft. The hammers knock on the conical tube at a high frequency as the centrifugal spray head rotates, and the knocking points change continuously, so that the conical tube vibrates to assist in unloading.

[0007] The crushing part includes a grinding ring arranged in the storage box and cooperating with the material guide cone. The phosphoric acid powder is crushed between the grinding ring and the material guide cone under the action of the hot air blown by the hot air mechanism above and the rotating centrifugal force of the storage box, and is thrown out through the discharge hole to be dried again by the hot air mechanism below.

[0008] As a preferred embodiment, the striking portion further comprises a first axis plate, a first connecting rod being rotatably mounted on the upper end of the material storage box via the first axis plate, a second connecting rod being rotatably mounted on the upper end of the material storage box via a second axis plate, and being positioned between two adjacent first connecting rods. Hammers are fixedly mounted on the upper ends of the first and second connecting rods via flexible columns. A driving member for driving the first and second connecting rods to reciprocate is provided on both the material storage box and the tapered tube. The hammer on the second connecting rod is lower in height than the hammer on the first connecting rod.

[0009] As a preferred solution, the driving member includes a waist-shaped groove, and the lower end of the connecting rod and the lower end of the second connecting rod are both provided with a waist-shaped groove. The upper end of the storage box is radially slidingly installed with an axle seat corresponding to the first connecting rod and the second connecting rod, and a roller is fixedly installed on the axle seat that slides through the corresponding waist-shaped groove. A connecting plate is fixedly installed on the end of the axle seat close to the center of the storage box, and a guide is provided between the conical tube and the connecting plate to guide the reciprocating movement of the connecting plate.

[0010] As a preferred solution, the inner ring wall of the straight tube is evenly fixed with a material stopping tube 1 along its axial direction, and the inner ring wall of the straight tube is fixed with a material stopping tube 2 located below the material stopping tube 1 through a support. The material stopping tube 1 is a frustum-shaped structure with an inner diameter of the upper end being larger than that of the lower end, and a material discharge hole is provided in the middle of a lower end of the material stopping tube. The material stopping tube 2 is a frustum-shaped structure with an inner diameter of the upper end being smaller than that of the lower end, and the upper end of the material stopping tube 2 is rotatably connected to the rotating shaft.

[0011] As a preferred solution, the hot air mechanism includes a through hole, a through hole is provided in the middle of the cover plate, the centrifugal spray head is coaxial with the through hole and the through hole is located outside the centrifugal spray head, a hot air cylinder is fixedly installed on the upper end of the cover plate, a through hole coaxial with the through hole is provided on the hot air cylinder, the inner cavity of the hot air cylinder is connected with the through hole, an air duct is installed on the drying tower and above the straight tube along its circumference, and an annular tube connected to the air duct is fixedly installed on the outer ring wall of the drying tower.

[0012] As a preferred solution, retaining rings are fixedly installed on the inner wall of the drying tower at positions corresponding to the conical tube and the straight tube, and limiting grooves are evenly provided on the upper ends of the retaining rings along their circumferences. Limiting blocks corresponding to the limiting grooves are fixedly installed on both the conical tube and the straight tube, and the inner diameter of the retaining ring located above is smaller than the outer diameter of the straight tube.

[0013] As a preferred solution, the grinding ring is fixedly installed on the lower end surface of the tapered tube, the inner ring surface of the grinding ring is set as an inclined grinding surface, and the gap between the inclined grinding surface and the outer wall of the guide cone gradually decreases from top to bottom.

[0014] As a preferred solution, the guide member includes a ring plate, which is fixedly installed on the outer wall of the lower end of the conical tube. A wave groove is opened along the circumference of the lower end of the ring plate, and a guide column is fixedly installed on the upper end of the connecting plate to slide in the wave groove.

[0015] As a preferred solution, a fixed plate is fixedly installed on the upper end of the hot air cylinder, the upper end of the centrifugal spray head is rotatably installed on the lower end of the fixed plate, and the upper end of the rotating shaft rotates through the fixed plate.

[0016] The above-mentioned one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects: First, the present invention uses a centrifugal spray head to atomize the phosphoric acid solution and immediately dry the atomized phosphoric acid solution, and then uses a knocking part to knock the conical tube to vibrate the conical tube, thereby promoting the falling of phosphoric acid powder and preventing the phosphoric acid powder from adhering. Then, the crushed phosphoric acid powder is thrown out by centrifugal force and dried again, thereby preventing adhesion and strengthening dehydration, thereby improving drying efficiency and quality.

[0017] Second, this invention utilizes a synergistic layered hot air system and a multi-stage material retaining design to overcome the limitations of traditional single-stage drying. A top hot air cylinder directly dries the atomized droplets through a through-hole. A secondary hot air system, comprised of annular tubes and inclined air ducts, delivers high-temperature air diagonally from the side walls of the drying tower, creating interlaced convection. This forces the phosphoric acid powder to repeatedly collide and stagnate within the multi-stage drying chamber composed of tapered and straight tubes, improving drying quality.

[0018] Third, this invention uses mechanical vibration to prevent adhesion, forced breakage, and secondary drying, solving the inefficiency of traditional gravity-based shedding. To prevent adhesion, a single drive coupled with a mechanical structure vibrates the conical tube during the initial drying period, effectively removing phosphoric acid powder adhering to the tube wall and improving both discharge speed and utilization.

[0019] Fourth, the present invention creates several staggered striking points by staggering the hammers axially relative to the rotating shaft. This allows striking at multiple locations on the conical tube, enhancing the tube's vibration and applying a more uniform striking force. This effectively shakes off powder layers at varying heights, reducing the axial gradient of powder accumulation, expanding the effective striking coverage, and improving the overall powder removal rate. Furthermore, the hammers' continuous circumferential movement constantly changes the striking points, dynamically adjusting the striking area to prevent powder from reattaching to specific locations.

[0020] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0022] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention.

[0023] Figure 2 It is a partial structural cross-sectional view of the present invention.

[0024] Figure 3 for Figure 2 A magnified view of the structure in Figure 2.

[0025] Figure 4 It is a structural schematic diagram of the knocking part of the present invention.

[0026] Figure 5 Schematic diagram of the structure of the driving member of the present invention.

[0027] Figure 6 It is a structural schematic diagram of the wave trough of the present invention.

[0028] Figure 7 It is a schematic structural diagram of the material blocking tube 1 and the material blocking tube 2 of the present invention.

[0029] 1. Material blocking mechanism; 2. Conical tube; 3. Retaining ring; 4. Limiting block; 5. Straight tube; 6. Material blocking tube 1; 7. Material blocking tube 2; 8. Material storage box; 9. Material guide cone; 10. Striking part; 11. Connecting rod 1; 12. Flexible column; 13. Hammer; 14. Connecting rod 2; 15. Driving member; 16. Shaft seat; 17. Connecting plate; 18. Guide member; 19. Ring plate; 20. Wave groove; 21. Guide column; 22. Crushing part; 23. Grinding ring; 24. Hot air mechanism; 25. Through hole; 26. Hot air cylinder; 27. Air duct; 28. Annular tube; 29. DETAILED DESCRIPTION

[0030] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0031] like Figure 1 and Figure 2 As shown, a multi-stage phosphoric acid spray dryer includes a drying tower 10; a cover plate 11 is detachably mounted on the upper end of the drying tower 10, and a hot air mechanism 3 is provided on the cover plate 11 and the drying tower 10. A centrifugal spray head 12 and a material blocking mechanism 2 for extending the falling time of phosphoric acid are rotatably mounted in the drying tower 10, and a rotating shaft 13 is coaxially fixedly mounted on the centrifugal spray head 12.

[0032] like Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, the material blocking mechanism 2 includes a conical tube 20 detachably mounted on the lower end of the cover plate 11, and the conical tube 20 and the straight tube 21 located below the centrifugal spray head 12 are sequentially arranged in the drying tower 10 from top to bottom. A material storage box 23 located inside the upper side of the straight tube 21 is rotatably mounted on the lower end of the conical tube 20, and the outer ring wall of the material storage box 23 is uniformly provided with discharge holes along its circumference. A material guide cone 24 is fixedly mounted on the inner bottom wall of the material storage box 23, and the lower end of the rotating shaft 13 is fixedly passed through the material guide cone 24 and the material storage box 23, and a knocking part 25 and a crushing part 26 are provided on the material storage box 23.

[0033] like Figure 2 and Figure 4 As shown, the knocking part 25 includes hammers 252 uniformly arranged along the circumference of the upper end of the storage box 23, and the hammers 252 are also axially staggered with the rotating shaft 13. The hammers 252 rotate with the centrifugal spray head 12 and knock the outer wall of the conical tube 20 at a high frequency, causing the conical tube 20 to vibrate to assist in unloading.

[0034] like Figure 2 、 Figure 3 and Figure 4 As shown, the crushing part 26 includes a grinding ring 260 arranged in the storage box 23 and cooperating with the guide cone 24. The dry phosphoric acid is crushed by passing between the grinding ring 260 and the guide cone 24 through the blowing of the hot air mechanism 3 and the rotation of the storage box 23, and is thrown out through the discharge hole for further drying.

[0035] like Figure 1 、 Figure 2 、 Figure 3 and Figure 4As shown, retaining rings 200 are fixedly installed on the inner wall of the drying tower 10 at positions corresponding to the tapered tube 20 and the straight tube 21. Limiting grooves are evenly provided on the upper end of the retaining ring 200 along its circumference. Limiting blocks 201 corresponding to the limiting grooves are fixedly installed on the tapered tube 20 and the straight tube 21, and the inner diameter of the retaining ring 200 located above is smaller than the outer diameter of the straight tube 21.

[0036] During the specific operation, the straight tube 21 is manually installed in the drying tower 10, and then the cover plate 11 is installed on the upper end of the drying tower 10. The straight tube 21 contacts the lower retaining ring 200, which supports the straight tube 21. The limit block 201 on the straight tube 21 is inserted into the limit groove on the lower retaining ring 200 to limit the rotation of the straight tube 21. The conical tube 20 contacts the upper retaining ring 200, and the limit block 201 on the conical tube 20 is inserted into the limit groove of the upper retaining ring 200, thereby limiting the downward movement and rotation of the conical tube 20. At the same time, the lower end of the rotating shaft 13 is inserted into the shaft frame provided in the drying tower 10, and the rotating shaft 13 can subsequently rotate on the shaft frame.

[0037] After the cover plate 11 is fixed to the upper end of the drying tower 10, the centrifugal spray head 12 rotates at high speed, and at the same time, the external conveyor transports the phosphoric acid solution into the centrifugal spray head 12. As the centrifugal spray head 12 rotates, the phosphoric acid is easily thrown out in an atomized state. At the same time, the hot air mechanism 3 transports hot air into the drying tower 10, and the phosphoric acid solution thrown out is dried into a crystalline powder by the hot air, while some of the solution that fails to dry in time flows on the inner wall of the conical tube 20 and is finally dried by the hot air. During the drying process, the hammer 252 strikes the conical tube 20 back and forth at high frequency, causing the conical tube 20 to vibrate, thereby causing the dried phosphoric acid crystals on the conical tube 20 to separate from the conical tube 20 and fall into the storage box 23, and the grinding ring 260 and the guide cone 24 cooperate to break the phosphoric acid crystals into suitable sizes. The broken phosphoric acid crystals are thrown out from the discharge hole on the storage box 23 and dried again to remove excess moisture in the phosphoric acid crystals.

[0038] like Figure 1 and Figure 2 As shown, the hot air mechanism 3 includes a through hole 30, a through hole 30 is opened in the middle of the cover plate 11, the centrifugal spray head 12 is coaxial with the through hole 30 and the through hole 30 is located outside the centrifugal spray head 12, a hot air cylinder 31 is fixedly installed on the upper end of the cover plate 11, and a through hole coaxial with the through hole 30 is opened on the hot air cylinder 31, and the inner cavity of the hot air cylinder 31 is connected with the through hole 30, and an air duct 32 is evenly inclined along the circumference of the drying tower 10 and above the straight tube 21, and an annular tube 33 connected with the air duct 32 is fixedly installed on the outer ring wall of the drying tower 10.

[0039] like Figure 2As shown, a fixing plate 14 is fixedly mounted on the upper end of the hot air cylinder 31 , an upper end of the centrifugal spray head 12 is rotatably mounted on the lower end of the fixing plate 14 , and an upper end of the rotating shaft 13 rotates and penetrates the fixing plate 14 .

[0040] like Figure 2 、 Figure 4 and Figure 5 As shown, the knocking part 25 also includes an axis plate 1, and the upper end of the storage box 23 is rotatably mounted with a connecting rod 1 250 through the axis plate 1, and the upper end of the connecting rod 1 250 is fixedly mounted with a hammer 252 through a flexible column 251. The upper end of the storage box 23 is rotatably mounted with a connecting rod 253 located between two adjacent connecting rods 1 250 through the axis plate 2, and the upper end of the connecting rod 253 is also fixedly mounted with a hammer 252 through a flexible column 251. The height of the hammer 252 on the connecting rod 253 is lower than the hammer 252 on the connecting rod 1 250, and the hammers of different heights The hammer 252 cooperates to form a staggered striking point layout, which can strike at multiple positions of the conical tube 20 to improve the vibration effect of the conical tube 20, and at the same time makes the striking force on the conical tube 20 more evenly distributed, avoiding local fatigue caused by repeated striking at a single height, so that powder layers at different heights can be effectively shaken off, expanding the effective striking coverage range, improving the overall powder removal rate, and reducing the axial accumulation gradient of the powder in the conical tube 20; the storage box 23 and the conical tube 20 are jointly provided with a driving part 4 for driving the connecting rod 1 250 and the connecting rod 2 253 to swing back and forth.

[0041] During operation, the external hot air system is connected to the hot air pipe 32 and the annular pipe 33, so that the hot air in the hot air pipe 32 is blown through the through hole 30 toward the phosphoric acid solution ejected by the centrifugal spray head 12, thereby drying the phosphoric acid solution. Meanwhile, the hot air in the annular pipe 33 is blown through the air pipe 32 toward the straight tube 21 to dry the phosphoric acid powder.

[0042] The upper end of the fixed plate 14 is fixedly mounted with a motor (not shown) by a bracket. The fixed plate 14 is connected to a liquid injection pipe connected to the centrifugal spray head 12. The motor output shaft is connected to the rotating shaft 13 and drives the rotating shaft 13 to rotate. The rotating shaft 13 then drives the centrifugal spray head 12 to rotate at a high speed. The centrifugal spray head 12 sprays the phosphoric acid solution. At the same time, the rotation of the rotating shaft 13 drives the storage box 23 to rotate. The storage box 23 then causes the lower ends of the connecting rod 1 250 and the connecting rod 2 253 to swing back and forth through the driving member 4. The connecting rod 1 250 and the connecting rod 2 253 then drive the corresponding hammer 252 to reciprocate and knock the tapered tube 20 through the flexible column 251, so that the tapered tube 20 vibrates to assist in blanking. During the process of the hammer 252 reciprocating and knocking the tapered tube 20, the flexible column 251 can play a buffering and vibration transmission role, prolong the contact time through elastic deformation, enhance the vibration transmission efficiency, and make the powder fall off more easily.

[0043] like Figure 2 、 Figure 4 and Figure 5 As shown, the driving member 4 includes a waist-shaped groove, and the lower end of the connecting rod 1 250 and the lower end of the connecting rod 2 253 are both provided with a waist-shaped groove. The upper end of the storage box 23 is radially slidably installed with an axle seat 40 corresponding to the connecting rod 1 250 and the connecting rod 2 253. A roller that slides through the corresponding waist-shaped groove is fixedly installed on the axle seat 40. A connecting plate 41 is fixedly installed at one end of the axle seat 40 close to the center of the storage box 23. A guide member 5 for guiding the connecting plate 41 to move back and forth is provided between the conical tube 20 and the connecting plate 41.

[0044] like Figure 2 、 Figure 4 、 Figure 5 and Figure 6 As shown, the guide member 5 includes a ring plate 50, and the ring plate 50 is fixedly installed on the outer wall of the lower end of the tapered tube 20. A wave groove 51 is opened along the circumference of the lower end of the ring plate 50, and a guide column 52 that slides with the wave groove 51 is fixedly installed on the upper end of the connecting plate 41.

[0045] like Figure 2 and Figure 3 As shown, the grinding ring 260 is fixedly installed on the lower end surface of the tapered tube 20, and the inner ring surface of the grinding ring 260 is set as an inclined grinding surface. The gap between the inclined grinding surface and the outer wall of the guide cone 24 gradually decreases from top to bottom.

[0046] like Figure 2 and Figure 7 As shown, the inner ring wall of the straight tube 21 is evenly fixed with a material blocking tube 210 along its axial direction, and the inner ring wall of the straight tube 21 is fixed with a material blocking tube 211 located below the material blocking tube 210 through a support. The material blocking tube 210 is a frustum structure with an inner diameter at the upper end being larger than that at the lower end, and a discharge hole is provided in the middle of the lower end of the material blocking tube 210. The material blocking tube 211 is a frustum structure with an inner diameter at the upper end being smaller than that at the lower end, and the upper end of the material blocking tube 211 is rotatably connected to the rotating shaft 13.

[0047] like Figures 2 to 7As shown, during specific operation, the rotation of the rotating shaft 13 drives the processing storage box 23 to rotate. During the rotation of the storage box 23, the guide column 52 will be driven to slide in the wave groove 51. The wave groove 51 pushes the shaft seat 40 to move radially back and forth through the guide column 52 and the connecting plate 41. The shaft seat 40 drives the corresponding connecting rod 1 250 or the lower end of the connecting rod 2 253 to swing back and forth through the roller and the waist groove. Because the connecting rod 1 250 and the connecting rod 2 253 are essentially a lever structure, the small swing of the lower end of the connecting rod 1 250 or the connecting rod 2 253 can be converted into a larger displacement and acceleration at its upper end, so that the connecting rod 1 250 and the connecting rod 2 253 drive the hammer 252 to perform reciprocating high-frequency knocking on the conical tube 20. The vibration generated by the knocking will cause the phosphoric acid powder on the inner wall of the conical tube 20 to fall off and fall into the crushing part 26. The rotation of the storage box 23 will also cause the hammer 252 to move continuously in the circumferential direction, so that the striking point is constantly changing, avoiding long-term fixed position striking that causes local wear of the conical tube 20, and preventing the powder from re-attaching at a specific position by dynamically adjusting the striking area. Combined with the vibration of the flexible column 251, it is more conducive to enhancing the shaking-off effect.

[0048] The rotation of the rotating shaft 13 drives the storage box 23 and the guide cone 24 to rotate synchronously, and the phosphoric acid powder falls between the guide cone 24 and the grinding ring 260. Under the action of the hot air blowing from the through hole 30 and the centrifugal force generated by the rotation of the storage box 23, the phosphoric acid powder enters between the guide cone 24 and the grinding ring 260. The guide cone 24 and the grinding ring 260 cooperate to grind the phosphoric acid powder passing through. The ground phosphoric acid powder is thrown out from the discharge hole as the storage box 23 rotates, and is dried again by the hot air blown from the hot air pipe 32 to remove excess moisture. The thrown phosphoric acid powder falls along the inclined inner wall of the material blocking pipe 1 210 and falls from the discharge hole to the inclined outer wall of the material blocking pipe 2 211, and then falls along the inclined outer wall of the material blocking pipe 2 211, and finally enters the external separator connected to the lower end of the drying tower 10 from the lower end of the drying tower 10, and the dry powder and the exhaust gas are separated by the external separator. By alternately arranging a plurality of first and second material blocking tubes 210 and 211, the falling path of the dry powder is extended, thereby increasing the falling time of the dry powder in the drying tower 10, thereby ensuring the drying effect of the phosphoric acid powder.

[0049] It should be noted that when the storage box 23 rotates, since the connecting rod 1 250 and the connecting rod 2 253 are not fixedly connected, their movement will lag behind the storage box 23. The elasticity of the flexible column 251 may also cause the movement of the hammer 252 to lag. However, movement lag is not necessarily a disadvantage. Reasonable use can form a vibration superposition effect, and multi-frequency vibration can enhance powder removal. The non-completely synchronous movement of the hammer 252 may instead randomize the vibration wave and enhance the shaking effect.

[0050] In order to avoid excessive lag, the following improvement measures can be taken: adjust the stiffness of the flexible column 251, and select a flexible column 251 with medium stiffness to balance the buffering and striking force; adjust the mass of the hammer 252, and use lightweight and high-strength materials such as titanium alloy to reduce inertia; adjust the rotation speed of the rotating shaft 13, shorten the motion cycle, and reduce the cumulative effect of lag; reduce friction resistance, and add lubricant or additional balls at the waist groove and roller shaft, and at the guide column 52 and the wave groove 51.

[0051] None of the above improvement measures require creative work. Selecting a medium-rigidity flexible column 251 is a conventional design in material mechanics. Adding lubricants or balls is a common means of reducing friction resistance in machinery. Using lightweight and high-strength materials is a common means of lightweighting. Adjusting the rotational speed is a common process parameter adjustment.

[0052] Of course, torsion springs (not shown in the figure) can also be installed between the shaft plate 1 and the connecting rod 1 250, and between the shaft plate 2 and the connecting rod 2 253 to assist the hammer 252 in quickly resetting and controlling the lag phase difference.

[0053] In the description of the present invention, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0054] Furthermore, the terms "first," "second," "number one," and "number two" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature designated as "first," "second," "number one," or "number two" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0055] In the description of the present invention, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "connected," "installed," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections or electrical connections; they may refer to direct connections or indirect connections through an intermediate medium; and they may refer to internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0056] The embodiments of this specific implementation method are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A multi-stage phosphoric acid spray dryer, comprising a drying tower; characterized in that: The upper end of the drying tower is provided with a cover plate, and a hot air mechanism is provided on the cover plate and the drying tower. A centrifugal spray head and a material blocking mechanism for extending the falling time of phosphoric acid are rotatably installed in the drying tower; wherein: The material blocking mechanism includes a tapered tube arranged at the lower end of the cover plate, and a tapered tube and a straight tube are sequentially arranged in the drying tower from top to bottom, located below the centrifugal spray head. A material storage box is rotatably mounted on the lower end of the tapered tube, and discharge holes are evenly opened on the outer ring wall of the material storage box along its circumference. A material guide cone is fixedly mounted on the bottom wall of the material storage box, and a knocking part and a crushing part are provided on the material storage box. A rotating shaft is coaxially fixedly installed on the centrifugal spray head, and the lower end of the rotating shaft is fixedly passed through the material guide cone and the material storage box; The knocking part includes hammers uniformly arranged along the circumference of the upper end of the storage box, and the hammers are also staggered with respect to the axial direction of the rotating shaft. The hammers rotate with the centrifugal spray head and knock on the conical tube at a high frequency, and the knocking points are constantly changing, so that the conical tube vibrates to assist in unloading. The crushing part includes a grinding ring arranged in the storage box and cooperating with the guide cone. The phosphoric acid powder is crushed between the grinding ring and the guide cone under the action of hot air blown by the hot air mechanism above and the centrifugal force of the storage box, and is thrown out through the discharge hole to be dried again by the hot air mechanism below. The knocking part also includes a connecting rod 1 and a connecting rod 2 rotatably mounted on the upper end of the storage box, and a hammer is fixedly mounted on the upper end of the connecting rod 1 and the upper end of the connecting rod 2 through a flexible column. The storage box and the tapered tube are jointly provided with a driving member for driving the connecting rod 1 and the connecting rod 2 to swing back and forth; An air duct is evenly and evenly installed on the drying tower and above the straight tube along its circumference. An annular tube connected with the air duct is fixedly installed on the outer ring wall of the drying tower.

2. A multi-stage phosphoric acid spray dryer according to claim 1, characterized in that: The knocking part also includes an axis plate 1, and a connecting rod 1 is rotatably installed on the upper end of the storage box through the axis plate 1, and a connecting rod 2 located between two adjacent connecting rods 1 is rotatably installed on the upper end of the storage box through the axis plate 2.

3. A multi-stage phosphoric acid spray dryer according to claim 2, characterized in that: The driving member includes a waist-shaped groove, and a waist-shaped groove is provided at the lower end of the connecting rod and the lower end of the second connecting rod. The upper end of the storage box is radially slidingly installed with an axle seat corresponding to the first connecting rod and the second connecting rod. A roller is fixedly installed on the axle seat and slides through the corresponding waist-shaped groove. A connecting plate is fixedly installed at one end of the axle seat close to the center of the storage box, and a guide is provided between the conical tube and the connecting plate to guide the reciprocating movement of the connecting plate.

4. A multi-stage phosphoric acid spray dryer according to claim 1, characterized in that: The inner ring wall of the straight tube is evenly fixed with a material blocking tube 1 along its axial direction, and the inner ring wall of the straight tube is fixed with a material blocking tube 2 located below the material blocking tube 1 through a support. The material blocking tube 1 is a truncated cone structure with an inner diameter of the upper end larger than that of the lower end, and a feeding hole is provided in the middle of a lower end of the material blocking tube. The material blocking tube 2 is a truncated cone structure with an inner diameter of the upper end smaller than that of the lower end, and the upper end of the material blocking tube 2 is rotatably connected to the rotating shaft.

5. A multi-stage phosphoric acid spray dryer according to claim 1, characterized in that: The hot air mechanism includes a through hole, a through hole is opened in the middle of the cover plate, the centrifugal spray head is coaxial with the through hole and the through hole is located outside the centrifugal spray head, a hot air cylinder is fixedly installed on the upper end of the cover plate, a through hole is opened on the hot air cylinder that is coaxial with the through hole, and the inner cavity of the hot air cylinder is connected to the through hole.

6. A multi-stage phosphoric acid spray dryer according to claim 1, characterized in that: On the inner wall of the drying tower, retaining rings are fixedly installed at positions corresponding to the tapered tube and the straight tube, and limiting grooves are evenly provided on the upper ends of the retaining rings along their circumferences. Limiting blocks corresponding to the limiting grooves are fixedly installed on the tapered tube and the straight tube, and the inner diameter of the retaining ring located above is smaller than the outer diameter of the straight tube.

7. A multi-stage phosphoric acid spray dryer according to claim 1, characterized in that: The grinding ring is fixedly mounted on the lower end surface of the tapered tube, the inner surface of the grinding ring is configured as an inclined grinding surface, and the gap between the inclined grinding surface and the outer wall of the guide cone decreases gradually from top to bottom.

8. A multi-stage phosphoric acid spray dryer according to claim 3, characterized in that: The guide member includes a ring plate, the outer wall of the lower end of the tapered tube is fixedly mounted with the ring plate, the lower end of the ring plate is provided with a wave groove along its circumference, and the upper end of the connecting plate is fixedly mounted with a guide column that slides in cooperation with the wave groove.

9. The multi-stage phosphoric acid spray dryer according to claim 5, characterized in that: The upper end of the hot air cylinder is fixedly mounted with a fixing plate, the upper end of the centrifugal spray head is rotatably mounted on the lower end of the fixing plate, and the upper end of the rotating shaft rotates and penetrates the fixing plate.

10. The multi-stage phosphoric acid spray dryer according to claim 2, characterized in that: The hammer on the second connecting rod is lower in height than the hammer on the first connecting rod.

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