A vertical fluidized bed granulator for compound fertilizer

Abstract

The application provides a compound fertilizer vertical fluidized bed granulator, which comprises a vertical tower body and a wind distribution plate, and the vertical tower body is divided into a fluidized chamber and a wind distribution box by the wind distribution plate; the wind distribution plate is a conical plate body arranged in the vertical tower body with a pointed top; at least one annular partition plate is arranged in the fluidized chamber and fixed to the wind distribution plate; and at least one discharge port is arranged on the annular partition plate. The vertical tower body of the compound fertilizer vertical fluidized bed granulator is divided into two parts, i.e., the fluidized chamber and the wind distribution box, by the wind distribution plate. The annular partition plate arranged in the fluidized chamber divides the fluidized chamber into different areas, the compound fertilizer particles can be sorted, the small-diameter compound fertilizer particles are limited to flow through to a certain extent, the residence time of the small particles in the fluidized chamber is prolonged, the flow through of the compound fertilizer particles meeting the standards is promoted to a certain extent, and therefore the yield of the granulation of the material in the fluidized chamber is improved, and the probability of the occurrence of dead beds is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of compound fertilizer processing equipment, in particular to a compound fertilizer vertical fluidized bed granulator. BACKGROUND

[0002] Fluidized bed granulation is a technology that material is put into a closed container at one time, the material is uniformly mixed in the container, the binder is sprayed at a constant speed, the binder and the material are fully mixed, and small particles are formed in the container, and the wet particles are dried by hot air sent from the bottom, and finally the finished dry particles are collected directly.

[0003] Fluidized bed spray granulation is the most common granulation method at present, air is generally used as the fluidizing gas, the air is preheated and then introduced into the bottom of the fluidized bed with a distribution plate, so that the solid powder to be granulated is in a fluidized state. Most of the liquid feed is sprayed into the fluidized bed by a double-fluid nozzle, and the speed of the fluidizing gas is large enough to make large particles move strongly and prevent caking.

[0004] The existing compound fertilizer fluidized bed granulator is processed by solving the traditional large particle urea fluidized bed granulation equipment. Because there is a big difference between the slurry characteristics of large particle urea and the slurry characteristics of compound fertilizer, the granulation rate of compound fertilizer is low, the amount of returned material is large, and the large particle compound fertilizer is easy to accumulate on the air distribution plate and die, which cannot meet the demand of large-scale batch production of compound fertilizer. SUMMARY

[0005] The present application aims to solve the problems of low yield, large amount of returned material, and large particle compound fertilizer easy to accumulate on the air distribution plate and die in the existing fluidized bed granulator during the processing of compound fertilizer, and provides a compound fertilizer vertical fluidized bed granulator.

[0006] The technical solution adopted by the present application to solve the technical problem is: a compound fertilizer vertical fluidized bed granulator, comprising a vertical tower body and an air distribution plate arranged in the vertical tower body, the vertical tower body is divided into a fluidization chamber located above the vertical tower body and an air distribution box located below the vertical tower body by the air distribution plate; the air distribution plate is a conical plate body arranged in the vertical tower body with the tip pointing upwards; at least one annular spacer plate is arranged in the fluidization chamber and fixed to the air distribution plate, and at least one discharge port is arranged on the annular spacer plate.

[0007] Further, the conical surface of the conical plate body of the air distribution plate forms an angle of 30°-45° with the horizontal plane.

[0008] Further, the air distribution plate is uniformly provided with a plurality of ventilation holes, the ventilation holes include through holes and tapered holes which are in communication with each other, and the tapered holes are located on the side of the air distribution plate close to the air distribution box.

[0009] Further, the fluidization chamber is provided with two annular partition plates fixed to the air distribution plate, the two annular partition plates are coaxially arranged in the fluidization chamber and the vertical tower body, the annular partition plate close to the center of the vertical tower body is a first partition plate, the discharge port on the first partition plate is a first discharge port, and the annular partition plate away from the center of the vertical tower body is a second partition plate, and the discharge port on the second partition plate is a second discharge port.

[0010] Specifically, the diameter of the first partition plate is 0.4-0.6 times the diameter of the vertical tower body, and the diameter of the second partition plate is 0.6-0.8 times the diameter of the vertical tower body.

[0011] Specifically, the first discharge port and the second discharge port are arranged in a circumferential direction.

[0012] Specifically, it further comprises a bottom blowing atomizing nozzle extending into the fluidization chamber from the center of the bottom of the vertical tower body, and the height of the top surface of the first discharge port of the first partition plate from the bottom surface of the vertical tower body is lower than the height of the bottom blowing atomizing nozzle from the bottom surface of the vertical tower body.

[0013] Specifically, the first partition plate is provided with a first opening at the connection with the air distribution plate, and the second partition plate is provided with a second opening at the connection with the air distribution plate.

[0014] Further, the air distribution box is provided with at least one annular sealing plate, the top surface of the annular sealing plate is sealingly fixed with the air distribution plate, and the bottom surface of the annular sealing plate is sealingly fixed with the bottom surface of the vertical tower body.

[0015] Specifically, the air distribution box is provided with two annular sealing plates, the two annular sealing plates are coaxially arranged in the air distribution box and the vertical tower body, the annular sealing plate close to the center of the vertical tower body is a first annular plate, and the annular sealing plate away from the center of the vertical tower body is a second annular plate.

[0016] The compound fertilizer vertical fluidized bed granulator has the advantages that the vertical tower body is divided into a fluidized chamber and a wind distribution box by a wind distribution plate, the annular partition plate arranged in the fluidized chamber divides the fluidized chamber into different areas, the compound fertilizer particles can be sorted, the small-diameter compound fertilizer particles are limited to flow, the residence time of the small particles in the fluidized chamber is prolonged, the compound fertilizer particles meeting the standard are promoted to flow, the product rate of the material granulation in the fluidized chamber is improved, and the returned material is reduced; the wind distribution plate is designed in a conical structure, the large particles of the material flow out quickly through the inclined design, the material accumulation on the wind distribution plate is prevented, and the probability of the occurrence of the dead bed is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a full sectional view of the compound fertilizer vertical fluidized bed granulator provided by the application;

[0018] Figure 2 is a full sectional view of the compound fertilizer vertical fluidized bed granulator provided by the application;

[0019] Figure 3 is a sectional view of the wind distribution plate in the compound fertilizer vertical fluidized bed granulator provided by the application.

[0020] In the drawing: 100 - compound fertilizer vertical fluidized bed granulator;

[0021] 10 - vertical tower body, 11 - feeding pipe, 12 - discharging pipe, 13 - top blowing atomizing nozzle,

[0022] 14 - bottom blowing atomizing nozzle, 15 - air inlet pipe, 16 - air outlet pipe;

[0023] 20 - wind distribution plate, 21 - ventilation hole, 211 - through hole, 212 - conical hole;

[0024] 30 - fluidized chamber, 31 - first partition plate, 311 - first discharging port, 312 - first opening;

[0025] 32 - second partition plate, 321 - second discharging port, 322 - second opening;

[0026] 40 - wind distribution box, 41 - first annular plate, 42 - second annular plate;

[0027] HR1 - height of the bottom blowing atomizing nozzle from the bottom surface of the vertical tower body;

[0028] HR2 - height of the feeding pipe bottom surface from the bottom surface of the vertical tower body;

[0029] HA1 - height of the top surface of the first partition plate from the bottom surface of the vertical tower body;

[0030] HA2-height of the first discharge port of the first partition plate from the bottom surface of the vertical tower body;

[0031] HA3-height of the first discharge port of the first partition plate;

[0032] HA4-height of the first opening of the first partition plate from the air distribution plate;

[0033] HA5-height of the bottom of the first discharge port of the first partition plate from the upper surface of the air distribution plate;

[0034] HB1-height of the top surface of the second partition plate from the bottom surface of the vertical tower body;

[0035] HB2-height of the second discharge port of the second partition plate from the bottom surface of the vertical tower body;

[0036] HB3-height of the second discharge port of the second partition plate;

[0037] HB4-height of the second opening of the second partition plate from the air distribution plate;

[0038] D0-diameter of the vertical tower body, D1-diameter of the first partition plate, D2-diameter of the second partition plate;

[0039] D3-diameter of the first annular sealing plate, D4-diameter of the second annular sealing plate;

[0040] L1-thickness of the air distribution plate, D5-diameter of the through hole, L2-length of the through hole. DETAILED DESCRIPTION

[0041] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0042] Referring to Figures 1-2 , the present application provides a compound fertilizer vertical fluidized bed granulator 100. The compound fertilizer vertical fluidized bed granulator 100 provided by the present application can be used in the processing of various compound fertilizers and can produce and process compound fertilizers in large quantities. The fluidized bed granulator 100 can preliminarily screen the compound fertilizer particles inside the fluidized chamber 30, prolong the flow time of the seed crystals in the fluidized chamber, and make the finished product rate of the compound fertilizer particles produced at a time reach more than 70%, thereby effectively reducing the return material and the probability of dead bed.

[0043] Further, as shown in Figure 1 and Figure 2 , the present application provides a full cross-sectional view of the compound fertilizer vertical fluidized bed granulator 100. As shown in Figure 1As shown, the fluidized bed granulator 100 includes a vertical tower body 10 and a wind distribution plate 20 arranged in the vertical tower body 10, and the vertical tower body 10 is divided into a fluidization chamber 30 located above the vertical tower body 10 and a wind distribution box 40 located below the vertical tower body 10 by the wind distribution plate 20.

[0044] The vertical tower body 10 is the main containing device for processing compound fertilizer, and the wind distribution plate 20 in the vertical tower body 10 plays a role in separating the internal space of the vertical tower body 10, injecting high-pressure gas into the inside of the wind distribution box 40, and the gas enters the inside of the fluidization chamber 30 through the wind distribution plate 20 to form a gas flow in the fluidization chamber 30 to play a fluidization role. The vertical tower body 10 has a cylindrical structure, and the wind distribution plate 20 divides the cylindrical vertical tower body 10 into two parts. The seed crystal can be injected into the fluidization chamber 30 of the vertical tower body 10 from the top center of the vertical tower body 10, and the compound fertilizer slurry is injected into the fluidization chamber 30 of the vertical tower body 10 from the bottom center of the vertical tower body 10. The slurry is atomized in the vertical tower body 10 and disturbed by the gas flow, and the material of the compound fertilizer particles is wrapped outside the seed crystal. The material of the compound fertilizer particles keeps flowing in the fluidization chamber 30, and the atomized slurry keeps wrapping on the material of the compound fertilizer, so that the particle size of the compound fertilizer particles continues to grow. When the compound fertilizer particles grow to the required particle size in the fluidization chamber 30 of the vertical tower body 10, they are discharged from the vertical tower body 10 to obtain the processed compound fertilizer particles.

[0045] Specifically, as shown in the drawings, Figure 1 The vertical fluidized bed granulator 100 for compound fertilizer provided by the present application further includes a feed pipe 11 extending into the fluidization chamber 30 from the top center of the vertical tower body 10. The feed pipe 11 is arranged at the top of the vertical tower body 10 and located at the center of the cylindrical barrel of the vertical tower body 10. The feed pipe 11 extends into the inside center of the fluidization chamber 30 from the top center of the vertical tower body 10. In the process of processing compound fertilizer, the seed crystal of the compound fertilizer enters the inside of the fluidization chamber 30 through the feed pipe 11. The feed pipe 11 is further provided with a lock valve outside the vertical tower body 10. The lock valve is installed at the top of the vertical tower body 10 and is controlled by frequency conversion. The frequency of the lock valve can be adjusted according to the granulation rate inside the vertical fluidized bed granulator 100 for compound fertilizer provided by the present application, so as to ensure that the number of seed crystals in the fluidization chamber 30 is within a controllable range. The lock valve can effectively adjust the flow of seed crystals entering the fluidization chamber 30.

[0046] Specifically, as shown in the drawings, Figure 1As shown, the compound fertilizer vertical fluidized bed granulator 100 further comprises a discharge pipe 12 extending from the side bottom of the vertical tower body 10 into the fluidized chamber 30, which is arranged on the side of the vertical tower body 10 and located at the bottom of the fluidized chamber 30 of the vertical tower body 10. In this embodiment, the distance between the bottom of the discharge pipe 12 and the air distribution plate 20 at the bottom of the fluidized chamber 30 is not more than 10 mm, so that the large particle compound fertilizer particles formed on the air distribution plate 20 can be discharged through the discharge pipe 12, the conical surface design of the air distribution plate 20 and the pushing of the compressed air in the air distribution box 40 can be guaranteed, the accumulation of large particle compound fertilizer particles on the air distribution plate 20 is minimized, and the problem of dead bed caused by the accumulation of large particle compound fertilizer particles is avoided. At the same time, the air lock valve arranged on the outside of the vertical tower body 10 of the discharge pipe 12 can ensure uniform discharge of the discharge pipe 12 while isolating the discharge of the gas in the fluidized chamber 30 from the discharge pipe 12. The air lock valve arranged on the discharge pipe 12 can also adjust the discharge amount according to the thickness of the material layer on the air distribution plate 20 and the size of the material in the feed pipe 11, so as to ensure the stability of the bed layer inside the fluidized bed granulator 100.

[0047] Further, as shown in the drawings, Figure 1 The compound fertilizer vertical fluidized bed granulator 100 further comprises a bottom blowing atomizing nozzle 14 extending from the bottom center of the vertical tower body 10 into the fluidized chamber 30. The top and bottom of the fluidized chamber 30 in the vertical tower body 10 are respectively provided with atomizing nozzles 13, which spray the compound fertilizer slurry, so that the inside of the fluidized chamber 30 is filled with the compound fertilizer slurry, and the crystal seeds are coated on the outer surface of the crystal seeds during the flow in the fluidized chamber 30. The bottom blowing atomizing nozzle 14 extends from the bottom center of the vertical tower body 10 into the inside of the fluidized chamber 30. The bottom blowing atomizing nozzle 14 is coaxially arranged with the feed pipe 11 and located on the central axis of the vertical tower body 10. The feed pipe 11 and the bottom blowing atomizing nozzle 14 are concentrically arranged to ensure that the crystal seeds fall in the fluidized chamber 30 and act against the compound fertilizer slurry from bottom to top, so as to promote the growth of the crystal seeds. In this embodiment, the bottom blowing atomizing nozzle 14 adopts a membrane type nozzle structure. One interface of the bottom blowing atomizing nozzle 14 is connected to compressed air, and the other interface is connected to the mixed compound fertilizer slurry. The compound fertilizer slurry and the compressed air are fully mixed at the nozzle to form atomized slurry. The pressure of the compressed air connected to the bottom blowing atomizing nozzle 14 is controlled at 0.5 MPa-0.6 MPa, and the pressure of the connected slurry is controlled at 0.2 MPa-0.4 MPa. After being sprayed out of the nozzle, the two are mixed to form an atomized state.

[0048] Specifically, as shown in the drawings, Figure 1As shown, the compound fertilizer vertical fluidized bed granulator 100 provided by the present application also includes at least two top blowing atomizing nozzles 13 extending from the top of the vertical tower body 10 into the fluidization chamber 30. The top blowing atomizing nozzles 13 are fixed to the inner side of the top of the vertical tower body 10, and are mainly used to capture small particle materials located above the inside of the fluidization chamber 30, and promote the growth of small particle materials. There can be 4-6 top blowing atomizing nozzles 13 uniformly distributed along the circumferential direction at the top of the vertical tower body 10, and the working principle of the top blowing atomizing nozzles 13 is consistent with that of the bottom blowing atomizing nozzles 14. The arrangement of the top blowing atomizing nozzles 13 enables the inside of the fluidization chamber 30 of the entire vertical tower body 10 to be fully filled with atomized compound fertilizer slurry, and especially the crystal seeds floating at a higher position can better contact more compound fertilizer slurry, thereby promoting the growth of the crystal seeds.

[0049] Further, as shown in Figure 1 The compound fertilizer vertical fluidized bed granulator 100 provided by the present application also includes at least one gas inlet pipe 15 extending from the bottom of the vertical tower body 10 into the air distribution box 40. In this embodiment, the bottom of the vertical tower body 10 has three gas inlet pipes (151, 152, 153), respectively, and different gas inlet pipes (151, 152, 153) inject different pressure gases into the air distribution box 40. After the different pressure gases pass through the air distribution box 40 and enter the fluidization chamber 30, they promote the disturbance of the air inside the fluidization chamber 30, thereby fully mixing the crystal seeds and the slurry entering the fluidization chamber 30 into one body. The number of the gas inlet pipes 15 is related to the specific structure of the air distribution box 40 and the fluidization chamber 30. As shown in Figure 1 The compound fertilizer vertical fluidized bed granulator 100 also includes a gas outlet pipe 16 arranged at the top of the vertical tower body 10, which communicates with an external dust collection system. Through the dust collection system, the fluidization gas in the fluidization chamber 30 and the dust generated during the drying process of the compound fertilizer particles can be sucked away.

[0050] Further, as shown in Figure 1As shown, the air distribution plate 20 provided in the vertical tower body 10 of the compound fertilizer vertical fluidized bed granulator 100 is a conical plate body arranged in the vertical tower body 10 with the tip pointing upwards. The air distribution plate 20 is designed in a conical structure with the tip pointing upwards, which can avoid the accumulation of large particle compound fertilizer particles on the air distribution plate 20. The air distribution plate 20 is designed as a slope in the fluidized chamber 30, which tilts from the center to the periphery. After falling onto the air distribution plate 20, the large particle compound fertilizer material slides to the periphery of the vertical tower body 10 along the slope of the air distribution plate 20. In the process of sliding, the large particle compound fertilizer material is disturbed on the conical surface by the high-pressure gas blown into the air distribution box 40, forming a downward rotating sliding process. Finally, the large particle material falling onto the air distribution plate 20 enters the discharge pipe 12 after being disturbed in the fluidized chamber 30. Compared with the traditional pleated structure, the conical plate body of the air distribution plate 20 is easier to process, reduces the processing difficulty, and can also reduce the accumulation of material on the air distribution plate 20. The conical design can also ensure the advancement of large particle material by gravity.

[0051] Specifically, as shown in the figure, Figure 1 The angle α between the conical surface of the conical plate body of the air distribution plate 20 and the horizontal plane is 30°-45°. The smaller the angle α between the conical surface of the conical plate body of the air distribution plate 20 and the horizontal plane, the smaller the downward sliding power of the large particle compound fertilizer material on the air distribution plate 20, and the easier the material accumulation. The larger the angle α between the conical surface of the conical plate body of the air distribution plate 20 and the horizontal plane, the faster the outflow speed of the compound fertilizer particles in the fluidized chamber 30, which is easy to cause the compound fertilizer particles to flow out before the particle size is fully wrapped, cannot achieve the expected particle size, and also causes the yield of the granulator to decrease. Therefore, the angle α between the conical surface of the conical plate body of the air distribution plate 20 and the horizontal plane is controlled between 30°-45°, which can avoid the accumulation of material on the air distribution plate 20, and can maximize the disturbance of the compressed air in the air distribution box 40 to the gas in the fluidized chamber 30, achieving the purpose of improving the yield.

[0052] Further, as shown in the figure, Figure 2 The internal structure of the air distribution plate 20 provided in the compound fertilizer vertical fluidized bed granulator 100 of the present application is shown. The air distribution plate 20 is uniformly distributed with a plurality of ventilation holes 21, which can guide and transmit the gas entering the air distribution box 40 to the fluidized chamber 30 according to the structure of the air distribution plate 20. In this embodiment, the air distribution plate 20 is designed in a conical shape, and the ventilation hole 21 is a hole diameter perpendicular to the conical surface. The gas enters the fluidized chamber 30 through the ventilation hole 21 of the air distribution plate 20, driving the flow of the gas inside the fluidized chamber 30.

[0053] Further, as shown in the figure, Figure 3As shown, the vent hole 21 comprises a through hole 211 and a tapered hole 212 which are in communication with each other, and the tapered hole 212 is located on the side of the air distribution plate 20 close to the air distribution box 40. The vent hole 21 is provided as the tapered hole 212 on the side of the air distribution box 40, wherein the tapered angle of the tapered hole 212 is 90°, so that the gas inside the air distribution box 40 enters the vent hole 21 first through the tapered hole 212, then enters the through hole 211, and finally enters the fluidization chamber 30. During the flow of the gas on the air distribution plate 20, the flow rate of the gas at the tapered hole 212 can be increased by using the Venturi principle. In this embodiment, the thickness L1 of the air distribution plate 20 is 8 mm, wherein the hole diameter D5 of the through hole 211 is 1.5-2 mm, and the length L2 of the through hole 211 is 2-5 mm.

[0054] Further, as Figure 3 and Figure 1As shown, it is a specific schematic view of the structure of the compound fertilizer vertical fluidized bed granulator 100 provided by the present application. The fluidized chamber 30 above the air distribution plate 20 in the vertical tower body 10 provided by the present application is provided with at least one annular spacing plate fixed on the air distribution plate 20, and the annular spacing plate (the first spacing plate 31 or the second spacing plate 32) is provided with at least one discharge port (the first discharge port 311, the second discharge port 321). In this embodiment, the annular spacing plate is a cylindrical annular structure, which is coaxially arranged with the vertical tower body 10, and the bottom of the annular spacing plate is fixed on the upper surface of the air distribution plate 20, and the top has a certain gap from the top of the vertical tower body 10. The setting of the annular spacing plate can form a preliminary screening effect in the fluidized chamber 30. The seed crystal entering the fluidized chamber 30 falls into the inside of the annular spacing plate and mixes with the atomized slurry sprayed at the bottom blowing atomizing nozzle 14 in the inside of the annular spacing plate. The seed crystal gradually grows into a small compound fertilizer particle in the inside of the annular spacing plate, and is disturbed in the inside of the annular spacing plate under the action of the air flow in the fluidized chamber 30. Due to the double action of gravity and fluidization, the larger compound fertilizer particles gradually fall down, and when falling to the height of the discharge port 311 of the annular spacing plate, the grown compound fertilizer particles flow from the inside of the annular spacing plate to the outside of the annular spacing plate; at the same time, the residence time of the small compound fertilizer particles is prolonged, the coating time is increased, and the granulation rate of the material in the fluidized chamber is improved. When the compound fertilizer particles flow out of the first discharge port 311 of the annular spacing plate, the compound fertilizer particles can continue to be disturbed on the outside of the annular spacing plate in the fluidized chamber 30, and continue to form agglomerates, stratify and accumulate with the slurry sprayed by the top blowing atomizing nozzle 13, and when the compound fertilizer particles grow up, they fall on the air distribution plate 20 under the action of gravity and slide on the conical surface of the air distribution plate 20 to the discharge pipe 12. Therefore, the more the number of the annular spacing plates arranged on the air distribution plate 20, the longer the residence time of the compound fertilizer particles in the fluidized chamber. However, the number of the annular spacing plates is not the more the better. If the number of the annular spacing plates is too large, the compound fertilizer particles in the inner annular spacing plates have grown to the required particles and directly fall on the air distribution plate 20, and cannot enter the outer annular spacing plates through the flow of gas, so that the space outside the annular spacing plates cannot play a role. Therefore, the number of the annular spacing plates arranged in the fluidized chamber 30 of the vertical tower body 10 of the compound fertilizer vertical fluidized bed granulator 100 provided by the present application is generally 1-4. In this way, the annular spacing plates can not only prolong the residence time of the seed crystal in the fluidized chamber, but also avoid the problem of waste of gas disturbance in the space outside the annular spacing plates.

[0055] Further, as Figure 2As shown, in this embodiment, the fluidization chamber 30 is provided with two annular partitions fixed to the air distribution plate 20. The two annular partitions are coaxially arranged with the vertical tower body 10 within the fluidization chamber 30. The annular partition closer to the center of the vertical tower body 10 is the first partition 31, and the discharge port on the first partition 31 is the first discharge port 311. The annular partition farther from the center of the vertical tower body 10 is the second partition 32, and the discharge port on the second partition 32 is the second discharge port 321. In this embodiment, the two annular partitions can serve as two separate partitions. Both the first partition 31 and the second partition 32 are cylindrical structures, and the bottoms of both the first partition 31 and the second partition 32 are fixed to the conical surface of the air distribution plate 20. The tops of the first partition 31 and the second partition 32 have a certain gap with the top surface of the vertical tower body 10, which can ensure that the slurry of the top-blown atomizing nozzle 13 can enter the interior of the first partition 31 and the second partition 32 from top to bottom, and can also ensure that the small compound fertilizer particles can be freely disturbed above.

[0056] Specifically, such as Figure 1 As shown, the diameter D1 of the first partition 31 is 0.4-0.6 times the diameter D0 of the vertical tower body 10. The first partition 31 is a cylindrical structure coaxially arranged with the cylindrical structure of the vertical tower body 10, and it is located near the central axis. The area enclosed by the first partition 31 is the inner layer region of the fluidization chamber 30 of the vertical tower body 10, which is the inner fluidization chamber. The diameter D0 of the vertical tower body 10 in the fluidized bed granulator 100 is generally between 2.5m and 4.5m. Correspondingly, the diameter D1 of the first partition 31 located in the vertical tower body 10 is controlled between 1m and 2.7m. Preferably, the diameter D1 of the first partition 31 is half the diameter D0 of the vertical tower body 10, meaning that the inner fluidization chamber separated by the first partition 31 within the vertical tower body 10 reaches half of the entire fluidization chamber 30 space. The diameter D2 of the second partition 32 is 0.6-0.8 times the diameter D0 of the vertical tower body 10. The second partition 32 is positioned between the first partition 31 and the vertical tower body 10, further dividing the area outside the first partition 31. Generally, the diameter D2 of the second partition 32 is controlled between 1.5m and 2m. Preferably, the diameter D2 of the second partition 32 is 0.75 times the diameter D0 of the vertical tower body 10, meaning the second partition 32 further divides the area outside the first partition 31 into two, forming a middle fluidizing chamber and an outer fluidizing chamber in the fluidizing chamber 30. The first partition 31 and the second partition 32, positioned on the air distribution plate 20, divide the internal space of the fluidizing chamber 30 in the vertical tower body 10 into three regions: an inner fluidizing chamber, a middle fluidizing chamber, and an outer fluidizing chamber.

[0057] Furthermore, in order to ensure that the seed crystal vertical tower 10 can be fully mixed with the slurry, such as... Figure 2As shown, the height HA1 of the top surface of the first partition plate 31 from the bottom surface of the vertical tower body 10 is lower than the height HR2 of the bottom surface of the feed pipe 11 from the bottom surface of the vertical tower body 10. The height HA1 of the top surface of the first partition plate 31 from the bottom surface of the vertical tower body 10 is 300-800 mm lower than the height HR2 of the bottom surface of the feed pipe 11 from the bottom surface of the vertical tower body 10. The height of the first partition plate 31 is lower than that of the feed pipe 11, so that when the small particles of the compound fertilizer particles float in the inner layer fluidization chamber, they can easily pass through the area above the first partition plate 31 and enter the middle layer fluidization chamber, and mix with the compound fertilizer slurry sprayed by the top blowing atomizing nozzle 13 to gradually grow. The height of the first partition plate 31 is lower than that of the feed pipe 11, so that the small particles of the compound fertilizer can flow into the middle layer fluidization chamber enclosed by the second partition plate 32, avoiding the backflow of the small particles of the material into the feed pipe 11.

[0058] At the same time, the height HB1 of the top surface of the second partition plate 32 from the bottom surface of the vertical tower body 10 is higher than the height HR2 of the bottom surface of the feed pipe 11 from the bottom surface of the vertical tower body 10. The height HB1 of the top surface of the second partition plate 32 from the bottom surface of the vertical tower body 10 is 300-800 mm higher than the height HR2 of the bottom surface of the feed pipe 11 from the bottom surface of the vertical tower body 10. The height of the second partition plate 32 is higher than that of the feed pipe 12, so as to limit the floating small particles of the compound fertilizer material in the middle layer fluidization chamber as much as possible, thereby prolonging the residence time of the small particles of the compound fertilizer material in the vertical tower body 10 as much as possible, and allowing the small particles of the compound fertilizer to grow as much as possible by agglomeration, stratification and accumulation of the compound fertilizer slurry sprayed by the top blowing atomizing nozzle 13.

[0059] Further, as shown in the drawings, Figure 2 In the fluidization chamber 30, two oppositely arranged first discharge ports 311 (only one is shown in the figure) are arranged on the first partition plate 31, and two oppositely arranged second discharge ports 321 (only one is shown in the figure) are arranged on the second partition plate 32. The first discharge port 311 on the first partition plate 31 and the second discharge port 321 on the second partition plate 32 are staggered in the circumferential direction. After the compound fertilizer particles enter the middle layer fluidization chamber through the first discharge port 311 of the first partition plate 31, they still need to continuously flow in the middle layer fluidization chamber enclosed by the second partition plate 32 to the area where the second discharge port 321 is located under the action of the gas flow. By staggering the discharge ports between the two partition plates, the residence time of the compound fertilizer particles in the middle layer fluidization chamber enclosed by the second partition plate 32 can be prolonged as much as possible, and the further growth of the compound fertilizer particles can be promoted. The discharge ports arranged on the first partition plate 31 and the second partition plate 32 can be arranged in different shapes according to the processing needs of different compound fertilizers, including but not limited to: grid shape, through-hole shape, fence shape, etc.

[0060] Further, as shown in the drawings, Figure 1As shown, the height HA2 of the top surface of the first discharge port 311 of the first partition plate 31 from the bottom surface of the vertical tower body 10 is lower than the height HR1 of the bottom blowing atomizing nozzle 14 from the bottom of the vertical tower body 10. After the crystal seeds enter the vertical tower body 10 through the feeding pipe 11, the crystal seeds fall down under the action of gravity and mix with the slurry sprayed by the bottom blowing atomizing nozzle 14 to form the material of the compound fertilizer particles under the effects of agglomeration, layering and accumulation. The material of the compound fertilizer particles gradually grows in the inner fluidized chamber surrounded by the first partition plate 31 and is layered as the size and weight of the particles gradually increase. The material fluctuates with the air flow blown by the air distribution box 40 from bottom to top, wherein the large compound fertilizer particles fall down and the small compound fertilizer particles float up. In order to prolong the time for which the material of the compound fertilizer particles stays in the inner fluidized chamber, the height of the first discharge port 311 provided on the first partition plate 31 is lower than the height of the bottom blowing atomizing nozzle 14, which can ensure that the crystal seeds are fully mixed with the slurry sprayed by the bottom blowing atomizing nozzle 14.

[0061] As shown in FIG. 1, the height HA5 of the first discharge port 311 provided on the first partition plate 31 from the air distribution plate 20 is consistent with the height HB5 of the second discharge port 321 provided on the second partition plate 32 from the air distribution plate 20. The height of the first discharge port 311 from the air distribution plate 20 is generally 500mm-800mm. The height HA3 of the first discharge port 311 and the height HB3 of the second discharge port 321 provided on the second partition plate 32 are controlled to be 100mm-500mm. Preferably, the height HA3 of the first discharge port 311 is 100mm. Figure 2 Further, as shown in FIG. 1, the height HA5 of the first discharge port 311 provided on the first partition plate 31 from the air distribution plate 20 is consistent with the height HB5 of the second discharge port 321 provided on the second partition plate 32 from the air distribution plate 20. The height of the first discharge port 311 from the air distribution plate 20 is generally 500mm-800mm. The height HA3 of the first discharge port 311 and the height HB3 of the second discharge port 321 provided on the second partition plate 32 are controlled to be 100mm-500mm. Preferably, the height HA3 of the first discharge port 311 is 100mm.

[0062] Figure 2 ​As shown, during the mixing process of seed crystals and slurry, large compound fertilizer particles inevitably reach or exceed the required particle size and weight and fall back onto the air distribution plate 20. To prevent large compound fertilizer particles from accumulating on the air distribution plate 20 after falling back, the first partition 31 has a first opening 312 at its connection with the air distribution plate 20, and the second partition 32 has a second opening 322 at its connection with the air distribution plate 20. The first opening 312 and the second opening 322 are staggered in the circumferential direction. The first opening 312 can discharge the large particles that have grown in the inner fluidization chamber and fallen back onto the air distribution plate 20 from the inner fluidization chamber to the middle fluidization chamber. The large particles will continue to be disturbed by the airflow in the middle fluidization chamber within the area enclosed by the second partition 32 and flow to the second opening 322, and then flow to the outer fluidization chamber through the second opening 322. Large particles in the outer fluidization chamber continue to be agitated by the airflow within the air distribution box 40 and move along the conical surface of the air distribution plate 20 to the discharge pipe 12. The placement of the first opening 312 and the second opening 322 prevents the accumulation of large particles at the connection points between the first and second partitions 31 and the air distribution plate 20, ensuring a continuous flow of gas into the fluidization chamber 30 from the air distribution box 40, and guaranteeing the continuity and stability of gas agitation within the fluidization chamber 30.

[0063] Specifically, the top surfaces of the first opening 312 on the first partition 31 and the second opening 322 on the second partition 32 are 5-15mm away from the upper surface of the air distribution plate 20. The first opening 312 and the second opening 322, due to the conical design of the air distribution plate 20, allow large-particle compound fertilizer material to slide downwards and outwards, preventing material accumulation on the air distribution plate 20 and reducing the risk of bed stagnation.

[0064] Furthermore, such as Figure 1 and Figure 1 As shown, the air distribution box 40 of the compound fertilizer vertical fluidized bed granulator 100 provided by the present invention is equipped with at least one annular sealing plate. The top surface of the annular sealing plate is sealed and fixed to the air distribution plate 20, and the bottom surface of the annular sealing plate is sealed and fixed to the bottom surface of the vertical tower body 10. Through the installation of this annular sealing plate, gases of different pressures can be input into the air distribution box 40. The number of annular sealing plates corresponds to the number of air inlet pipes 15 in the vertical tower body 10. If no annular sealing plate is installed in the air distribution box 40, only one air inlet pipe 15 is needed in the vertical tower body 10 to meet the requirement of supplying high-pressure gas to the fluidization chamber 30. However, after installing one annular sealing plate in the air distribution box 40, two air inlet pipes 15 are needed to input gases of different pressures into two different areas inside and outside the annular sealing plate.

[0065] The number of annular sealing plates arranged in the air distribution box 40 of the vertical tower body 10 corresponds to the number of annular spacing plates arranged in the fluidization chamber 30. In the embodiment, two annular spacing plates, i.e., the first spacing plate 31 and the second spacing plate 32, are arranged in the fluidization chamber 30, and correspondingly, two annular sealing plates are arranged in the air distribution box 40. As shown in Figure 2 Figure 1 the air distribution box 40, the two annular sealing plates are coaxially arranged in the air distribution box 40 with the vertical tower body 10. Among them, the annular sealing plate close to the center of the vertical tower body 10 is the first annular plate 41, and the annular sealing plate far from the center of the vertical tower body 10 is the second annular plate 42. The first annular plate 41 and the second annular plate 42 divide the space of the air distribution box 40 into three regions, i.e., inner, middle and outer regions. Correspondingly, the bottom of the vertical tower body 10 of the present application is provided with three air inlet pipes (151, 152, 153) corresponding to the inner, middle and outer regions in the air distribution box 40 respectively, and different high-pressure gases are delivered respectively. The high-pressure gases delivered in the inner, middle and outer regions of the air distribution box 40 communicate with the inner, middle and outer regions of the fluidization chamber 30, so as to realize different gas pressures in the three regions and promote the disturbance of the gas in the three regions.

[0066] Among them, the pressure value delivered in the region close to the center of the vertical tower body 10 in the air distribution box 40 is smaller, and the pressure value delivered in the region close to the side wall of the vertical tower body 10 is larger. In the embodiment, the pressure of the air inlet pipe 151 delivering compressed gas to the inside of the first annular plate 41 is 20-25 KPa, the pressure of the air inlet pipe 152 delivering compressed gas to the inside of the second annular plate 42 is 24-28 KPa, and the pressure of the air inlet pipe 153 delivering compressed gas to the outside of the second annular plate 42 is 26-30 KPa.

[0067] Further, in order to better increase the disturbance effect of the gas in the fluidization chamber 30, the three regions of the air distribution box 40 and the three regions of the fluidization chamber 30 have a certain staggered layer, so that the disturbance effect of the gas flow in the three regions of the fluidization chamber 30 can be increased, and the fluidization effect in the fluidization chamber 30 can be improved. That is, the diameters of the annular sealing plates in the air distribution box 40 are different from the diameters of the annular spacing plates in the fluidization chamber. As a preferred, the diameter D3 of the first annular plate 41 in the air distribution box 40 is 100-200mm smaller than the diameter D1 of the first spacing plate 31 in the fluidization chamber 30. The diameter D4 of the second annular plate 42 in the air distribution box 40 is 100-200mm smaller than the diameter D2 of the second spacing plate 32 in the fluidization chamber 30. The staggered layer design of the first annular plate 41 and the first spacing plate 31 in the vertical direction can increase the gas flow effect between the inner fluidization chamber and the middle fluidization chamber in the fluidization chamber 30. The staggered layer design of the second annular plate 42 and the second spacing plate 32 in the vertical direction can increase the air flow effect between the middle fluidization chamber and the outer fluidization chamber in the fluidization chamber 30. By improving the air flow effect inside the fluidization chamber 30, the fluidization effect in the fluidization chamber 30 can be improved, and the granulation rate of the granulator 100 can be improved.

[0068] The processing process of the composite fertilizer vertical fluidized bed granulator 100 provided by the present application is as follows:

[0069] Firstly, the seeds enter the fluidization chamber 30 of the vertical tower body 10 through the feeding pipe 11, and the seeds fall into the inner layer fluidization chamber surrounded by the first spacing plate 31, and meet the composite fertilizer slurry sprayed by the bottom blowing atomizing nozzle 13 in the opposite direction. The seeds and the composite fertilizer gradually grow into composite fertilizer particles under the agglomeration, stratification and accumulation of the seeds and the composite fertilizer in the inner layer fluidization chamber. With the continuous growth of the composite fertilizer particles, the smaller composite fertilizer particles will float above the inner layer fluidization chamber under the fluidization effect, and the larger composite fertilizer particles will fall back to the air distribution plate 20 under the fluidization effect.

[0070] Then, when the composite fertilizer particles grow and fall back to the height of the first discharge port 311 of the first spacing plate 31, the composite fertilizer particles will pass through the first spacing plate 31 from the inner layer fluidization chamber to the middle layer fluidization chamber along the first discharge port 311 under the fluidization effect, and continue to grow in the middle layer fluidization chamber. The composite fertilizer particles entering the middle layer fluidization chamber further agglomerate, stratify and accumulate to grow.

[0071] At the same time, the small particle compound fertilizer particles floating in the inner fluidized chamber will also pass through the first partition plate 31 into the middle fluidized chamber from the gap between the upper part of the first partition plate 31 and the vertical tower body 10 under the fluidization effect, and the second partition plate 32 has a large height, so that the small particle compound fertilizer particles will continue to grow in the middle fluidized chamber and grow together with the compound fertilizer particles entering from the first opening 312 of the first partition plate 31.

[0072] Then, the grown compound fertilizer particles will gradually fall to the height of the second discharge port 321 of the second partition plate 32, pass through the second partition plate 32 along the second discharge port 321 into the outer fluidized chamber under the fluidization effect, and continue to grow in the outer fluidized chamber to reach the compound fertilizer particles of the required particle size. In the outer fluidized chamber, the compound fertilizer particles will enter the discharge pipe 12 under the fluidization effect and be discharged.

[0073] Finally, the large particle compound fertilizer particles that cannot be pulverized by high-speed gas and fall back onto the air distribution plate 20 after growing in the inner fluidized chamber will be driven by the conical surface design of the air distribution plate 20 and the thrust of the gas flow to enter the middle fluidized chamber from the first opening 312 of the first partition plate 31, and together with the larger compound fertilizer particles in the middle fluidized chamber, enter the outer fluidized chamber from the second opening 322 of the second partition plate 32, and move to the discharge pipe 12 under the fluidization effect and be discharged.

[0074] The particle size of the compound fertilizer particles processed by the vertical fluidized bed granulator 100 provided by the present application can reach 2.5-4.25mm, and the yield of the compound fertilizer particles processed at a time can be about 70%, which is 20%-30% higher than that of the traditional granulator 100, thereby effectively reducing the number of reprocessing and greatly improving the production efficiency and production capacity of compound fertilizer processing.

[0075] The vertical tower body 10 is divided into a fluidized chamber 30 and a wind distribution box 40 by the air distribution plate 20, wherein the annular partition plate arranged in the fluidized chamber 30 divides the fluidized chamber into different areas, that is, in the present embodiment, the fluidized chamber 30 is divided into three areas, i.e., an inner fluidized chamber, a middle fluidized chamber and an outer fluidized chamber, by the first partition plate 31 and the second partition plate 32 arranged therein. The annular partition plate can sort the compound fertilizer particles, has a certain limiting flow effect on small particle compound fertilizer particles, can prolong the residence time of small particles in the fluidized chamber, has a certain promoting flow effect on the compound fertilizer particles meeting the standard, thereby improving the yield of the material particles in the fluidized chamber and reducing the reprocessing; the air distribution plate 20 adopts a conical structure design, which can quickly flow out the large particle material through the inclined design, prevent the accumulation of material on the air distribution plate 20, and reduce the probability of occurrence of dead bed.

[0076] The above merely preferred embodiments of the present application are not used to limit the present application, any modification, equivalent replacement and improvement etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A compound fertilizer vertical fluidized bed granulator characterized by, The vertical tower body is divided into a fluidization chamber above the vertical tower body and a wind distribution box below the vertical tower body by a wind distribution plate arranged in the vertical tower body with a conical plate body arranged in the vertical tower body with a tip pointing upwards; at least one annular partition plate is arranged in the fluidization chamber and fixed to the wind distribution plate, and at least one discharge port is arranged on the annular partition plate; An included angle between the conical surface of the conical plate body of the wind distribution plate and a horizontal plane is 30°-45°; A plurality of ventilation holes are uniformly distributed on the wind distribution plate, the ventilation holes include through holes and conical holes which are in communication with each other, and the conical holes are located on a side of the wind distribution plate close to the wind distribution box; Two annular partition plates are arranged in the fluidization chamber and fixed to the wind distribution plate, the two annular partition plates are coaxially arranged in the fluidization chamber and the vertical tower body, the annular partition plate close to the center of the vertical tower body is a first partition plate, the discharge port on the first partition plate is a first discharge port, and the annular partition plate away from the center of the vertical tower body is a second partition plate, the discharge port on the second partition plate is a second discharge port; The first discharge port and the second discharge port are staggered in the circumferential direction; The first partition plate is provided with a first opening at the connection with the wind distribution plate, and the second partition plate is provided with a second opening at the connection with the wind distribution plate; At least one annular sealing plate is arranged in the wind distribution box, the top surface of the annular sealing plate is sealingly fixed to the wind distribution plate, and the bottom surface of the annular sealing plate is sealingly fixed to the bottom surface of the vertical tower body; Two annular sealing plates are arranged in the wind distribution box, the two annular sealing plates are coaxially arranged in the wind distribution box and the vertical tower body, the annular sealing plate close to the center of the vertical tower body is a first annular plate, and the annular sealing plate away from the center of the vertical tower body is a second annular plate; The first annular plate and the first partition plate are staggered in the vertical direction, and the second annular plate and the second partition plate are staggered in the vertical direction.

2. A vertical fluidized bed granulator for compound fertilizer as claimed in claim 1, characterized in that, The diameter of the first partition plate is 0.4-0.6 times the diameter of the vertical tower body, and the diameter of the second partition plate is 0.6-0.8 times the diameter of the vertical tower body.

3. A vertical fluidized bed granulator for compound fertilizer as claimed in claim 1, characterized in that, A bottom blowing atomizing nozzle is further arranged in the fluidization chamber from the center of the bottom of the vertical tower body, and the height of the top surface of the first discharge port of the first partition plate from the bottom surface of the vertical tower body is lower than the height of the bottom blowing atomizing nozzle from the bottom surface of the vertical tower body.

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