4-trifluoromethyl nicotinic acid continuous fluidized bed drying equipment and drying process

Abstract

The invention relates to the technical field of fluidized bed drying, in particular to 4-trifluoromethyl nicotinic acid continuous fluidized bed drying equipment and a drying technology.The 4-trifluoromethyl nicotinic acid continuous fluidized bed drying equipment comprises a fluidized bed equipment body, an inner cavity is formed in a bed body, a bed layer structure is arranged in the inner cavity, and the bed layer structure comprises a fixed bed plate and a movable bed plate; the movable bed board is movably arranged above the fixed bed board through a driving mechanism. The movable bed plate is driven by the driving mechanism to periodically slap the fixed bed plate, water-containing caking materials can be effectively crushed by mechanical impact force generated by slapping, the water-containing caking materials are dispersed into fine particles to enter a fluidized state, the bump structures are arranged on the upper surface of the movable bed plate, the capacity of shearing and crushing the caking is enhanced, and meanwhile, the caking effect is improved. The air holes in the fixed bed layer are trumpet-shaped, and materials blocked in the trumpet-shaped air holes can be easily shaken off in combination with the slapping action, so that the self-cleaning of the first air holes is realized, and the continuous smoothness of an air path and the uniformity of air flow distribution are ensured.

Description

Technical Field

[0001] This invention relates to the field of fluidized bed drying technology, and more specifically, to a continuous fluidized bed drying device and drying process for 4-trifluoromethylnicotinic acid. Background Technology

[0002] In the field of fine chemicals and pharmaceutical intermediates, 4-trifluoromethylnicotinic acid is an important fluorine-containing organic compound for drug synthesis and pesticide preparation. However, during production, 4-trifluoromethylnicotinic acid is prone to residual crystallization mother liquor and adsorbed solvent, or deliquescence and crystal form transformation due to excessive moisture, which directly affects the purity and quality of subsequent products. Therefore, the drying process is crucial to ensuring product quality. At present, the industry mostly uses fluidized bed drying equipment to complete the drying process. It relies on airflow to make the material "boiling" to achieve efficient heat and mass transfer to remove moisture.

[0003] However, 4-trifluoromethylnicotinic acid powder is easily agglomerated due to temperature changes and moisture gradients, which directly disrupts the normal fluidization state in the fluidized bed. Unagglomerated light powder can be smoothly "boiled" and dried with the airflow, while agglomerated material, due to its increased density and mass, is difficult to be lifted by the airflow. It not only fails to fully contact the hot airflow, resulting in uneven drying and a significant decrease in efficiency, but also accumulates on the bed surface. At the same time, the existing fluidized bed bed plates mostly use a straight hole design for the pores, and the accumulated agglomerated material is easy to embed into the pores, causing pore blockage.

[0004] To address the issues of agglomeration and pore blockage in fluidized bed drying, existing technologies have made some attempts, such as adding air caps to the bed plate to improve airflow distribution and adding disturbance devices to enhance material flowability. However, limitations still exist: the air cap structure can only optimize the airflow direction and cannot specifically address the sticky agglomeration of 4-trifluoromethylnicotinic acid; conventional disturbances can easily lead to excessive material splashing.

[0005] Therefore, there is an urgent need for a continuous fluidized bed drying equipment and drying process for 4-trifluoromethylnicotinic acid to solve the above problems. Summary of the Invention

[0006] This invention provides a continuous fluidized bed drying device and process for 4-trifluoromethylnicotinic acid. It utilizes a dual-gas chamber with differentiated temperature control to introduce drying gas, guide plates to disperse the material, a drive mechanism to periodically tap the movable bed plate, and funnel-shaped air holes to create a high-speed airflow. This ensures that 4-trifluoromethylnicotinic acid is fully dispersed and comes into contact with the drying gas, efficiently completing fluidized bed drying within the fluidized bed device's cavity for subsequent processes. This solves the problems mentioned in the background art, namely:

[0007] When drying 4-trifluoromethylnicotinic acid powder, it is prone to clumping due to temperature changes and moisture gradients, which disrupts the fluidization state, leading to uneven drying, reduced efficiency, and blockage of the bed plate pores.

[0008] To achieve the above objectives, one objective of the present invention is to provide a continuous fluidized bed drying device for 4-trifluoromethylnicotinic acid, comprising a fluidized bed device body, which is composed of a base frame and a bed body. The interior of the bed body forms an inner cavity, and the bottom of the bed body is provided with a gas chamber for introducing drying gas. One side wall of the bed body is provided with an inlet for feeding materials, and the other side wall of the bed body is provided with a outlet.

[0009] A gas outlet is provided at the top of the inner cavity near the discharge port. The inner cavity is provided with a bed structure, which includes: a fixed bed board, which is fixedly installed in the lower part of the inner cavity, and the fixed bed board has a plurality of first air holes penetrating its upper and lower surfaces; and a movable bed board, which is movably disposed above the fixed bed board by a driving mechanism, and the movable bed board has a second air hole corresponding to the first air hole, the diameter of the second air hole being larger than the diameter of the first air hole.

[0010] The drive mechanism is used to drive the movable bed board to perform a reciprocating striking motion on the fixed bed board, so as to break up the clumps of material falling on it and clear the first air hole.

[0011] In the above technical solution, because it is necessary to solve the problems of easy agglomeration, uneven material dispersion, easy pore blockage and low drying efficiency during the drying process of 4-trifluoromethylnicotinic acid, a dual air chamber is set up to adapt to the drying needs of different areas. Combined with the bed structure and drive mechanism, the material is crushed by impact and the pores are cleared. Then, the material is concentrated by the guide plate, the non-stick coating prevents sticking, and the funnel-shaped pores enhance the airflow effect, and finally a continuous fluidized bed drying equipment is formed to ensure efficient fluidized drying of materials and guarantee product quality.

[0012] Based on this, the drive mechanism has a multi-point structure, including multiple support rods located at the end corners of the two air chambers. Each support rod contains a cylinder, the cylinder body of which is fixed to the fixed bed plate, and the end of its push rod is connected to the bottom of the movable bed plate. This multi-point structure design, by arranging multiple support rods at the end corners of the two air chambers and incorporating cylinders, allows the cylinder bodies to be fixed to the fixed bed plate and the push rods to connect to the movable bed plate. This provides a uniform and stable driving force to the movable bed plate, ensuring balanced force during reciprocating striking motion and preventing tilting or instability caused by single-point drive. Simultaneously, the support rods located at the end corners of the air chambers reduce obstruction of the airflow path within the chambers. Combined with the support rods extending into the end air inlet chambers, this also helps to guide airflow, eliminate dead airflow corners, and improve the efficiency of the drying gas passing through the bed structure, thereby ensuring the crushing effect and drying uniformity of 4-trifluoromethylnicotinic acid.

[0013] Specifically, the movable bed board has a lightweight structure, including an aluminum alloy frame and an elastic buffer layer. The elastic buffer layer is located at the bottom of the movable bed board and provides a cushioning effect when the movable bed board is in contact with the fixed bed board.

[0014] On the one hand, the aluminum alloy frame significantly reduces the overall weight of the movable bed board, reducing the load on the drive mechanism when the cylinder drives the bed board to perform reciprocating striking motions. This reduces drive energy consumption and improves the response speed of the bed board's striking action, ensuring timely breaking of agglomerated materials and clearing of air pores. On the other hand, the elastic buffer layer at the bottom can directly absorb the mechanical impact force generated by the contact between the movable and fixed bed boards during the striking process, avoiding direct collision between the aluminum alloy frame and the metal material of the fixed bed board, reducing wear on the bed board structure, and extending the service life of both the fixed and movable bed boards. Furthermore, the buffer layer can weaken the interference of bed board vibration on the airflow in the air chamber during the striking process, preventing the airflow from becoming turbulent due to violent vibration, and ensuring that the drying airflow continuously and evenly passes through the first air pore of the fixed bed board, providing a guarantee for the stable fluidized drying of 4-trifluoromethylnicotinic acid.

[0015] In addition, a guide plate is inclinedly arranged inside the inner cavity. The guide plate has a mesh structure. The high end of the guide plate is connected to the inner wall of the inner cavity and its height is higher than the feed inlet. The low end of the guide plate extends to the top of the bed structure. A guide cavity is formed between the guide plate and the bed structure. The height of the low end of the guide plate is higher than the highest position that the movable bed board can reach during the tapping motion.

[0016] The second objective of this invention is to provide a drying process for 4-trifluoromethylnicotinic acid, using the aforementioned continuous fluidized bed drying equipment for 4-trifluoromethylnicotinic acid, comprising the following steps:

[0017] S1. The 4-trifluoromethylnicotinic acid to be dried is fed into the inner cavity of the fluidized bed equipment body through the feed port located above the side wall of the bed;

[0018] S2. In the material, the lighter parts are carried by the dry airflow blown in from the air chamber and are in a fluidized boiling state in the inner cavity. In the material, the water-containing clumps of 4-trifluoromethylnicotinic acid fall or slide down through the inclined guide plate and finally reach the upper surface of the movable bed plate.

[0019] S3. The drive mechanism starts, driving the movable bed plate to perform a periodic reciprocating striking motion relative to the fixed bed plate below. The striking motion can break up the clumps of material accumulated on the upper surface of the movable bed plate, and at the same time, the impact force shakes off the material blocking the first air hole of the fixed bed plate, keeping the air passage unobstructed.

[0020] S4. After being crushed by impact, the 4-trifluoromethylnicotinic acid block becomes lighter and is carried away from the bed structure by the rising drying airflow, enters the inner cavity to participate in fluidization and boiling and complete the drying process.

[0021] S5. After drying, 4-trifluoromethylnicotinic acid is discharged through the outlet, and the airflow in the inner cavity is discharged from the gas outlet.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] The movable bed plate is driven by a drive mechanism to periodically beat the fixed bed plate. The mechanical impact force generated by the beating can effectively break up the water-containing agglomerated materials, dispersing them into fine particles and allowing them to enter a fluidized state. In addition, the raised structure on the upper surface of the movable bed plate concentrates stress and enhances the ability to shear and break up agglomerated materials. At the same time, by setting the first air hole on the fixed bed layer as a funnel-shaped air hole, combined with the beating action, it is easier to shake off the material stuck in the funnel-shaped air hole of the fixed bed plate, realizing the self-cleaning of the first air hole and ensuring the continuous unobstructed air passage and uniform airflow distribution.

[0024] The funnel-shaped vents create a high-speed airflow at the vent outlet, which enhances the initial impact and lifting force of the airflow on the material, making it more conducive to the initial fluidization of the material bed and maintaining a stable "boiling" state, thereby improving the heat and mass transfer efficiency. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0026] Figure 2 This is a schematic diagram of the gas and material inlet and outlet structure of the present invention;

[0027] Figure 3 This is a schematic diagram of the internal structure of the air chamber of the present invention;

[0028] Figure 4 For the present invention Figure 3 A schematic diagram of the structure at point A;

[0029] Figure 5 This is a schematic diagram of the cross-sectional structure of the internal cavity of the present invention;

[0030] Figure 6 This is a schematic diagram of the movable bed board activation structure of the present invention;

[0031] Figure 7 This is a schematic diagram of the connection structure between the movable bed board and the fixed bed board of the present invention;

[0032] Figure 8 This is a schematic diagram of the cross-sectional structure of the fixed bed board of the present invention;

[0033] Figure 9 For the present invention Figure 8 A schematic diagram of the structure at point B;

[0034] Figure 10 This is a partial top view of the bed structure of the present invention.

[0035] The meanings of the labels in the diagram are as follows:

[0036] 1. Fluidized bed equipment body; 11. Base frame; 12. Bed body; 13. Gas chamber; 14. Feed inlet; 15. Discharge outlet; 16. Gas outlet; 17. Inner cavity;

[0037] 2. Bed structure; 21. Fixed bed board; 22. Movable bed board; 23. First air vent; 24. Second air vent; 25. Protruding point structure;

[0038] 3. Drive mechanism; 31. Support rod; 32. Cylinder;

[0039] 4. Guide plate; 41. Guide cavity. Detailed Implementation

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

[0041] Example 1: Please refer to Figure 1 , Figure 2 , Figure 3 , Figure 5 and Figure 6 As shown, the purpose of this embodiment is to provide a continuous fluidized bed drying device for 4-trifluoromethylnicotinic acid, including a fluidized bed device body 1, which is composed of a base frame 11 and a bed body 12, with an inner cavity 17 formed inside the bed body 12; and a gas chamber 13 for introducing drying gas is provided at the bottom of the bed body 12.

[0042] The bed body 12 has a material inlet 14 on one side wall and a material outlet 15 on the other side wall. A gas outlet 16 is located at the top of the inner cavity 17 near the material outlet 15. The inner cavity 17 contains a bed structure 2, which includes:

[0043] A fixed bed board 21 is fixedly installed in the lower part of the inner cavity 17, and multiple first air holes 23 penetrating its upper and lower surfaces are provided on the fixed bed board 21; a movable bed board 22 is movably disposed above the fixed bed board 21 by a drive mechanism 3, such as... Figure 10The movable bed board 22 has a second air hole 24 corresponding to the first air hole 23, and the diameter of the second air hole 24 is larger than the diameter of the first air hole 23.

[0044] The drive mechanism 3 is used to drive the movable bed board 22 to perform reciprocating striking motion on the fixed bed board 21, so as to break up the agglomerated material falling on it and clear the first air hole 23.

[0045] In the fluidized bed equipment body 1, the drying gas needs to be externally introduced into the gas chamber 13, and then pass through the bed structure 2 into the inner cavity 17 to dry the water-containing 4-trifluoromethylnicotinic acid. Specifically, there are two gas chambers 13, one of which is an end gas inlet and the other gas chamber 13 is a side gas inlet.

[0046] The drive mechanism 3 has a multi-point structure, including multiple support rods 31. The multiple support rods 31 are located at the end corners of the two air chambers 13 respectively. Each of the multiple support rods 31 has a cylinder 32 installed inside. The cylinder body is fixed on the fixed bed plate 21, and the end of its push rod is connected to the bottom of the movable bed plate 22.

[0047] like Figure 3 As shown, there are two gas chambers 13, which are connected to the dry gas via the end and the side respectively (see attached diagram). Figure 3 The dashed arrows in the text indicate the directions of the two air inflow chambers. These two air chambers 13 can be supplied with dry gases at different temperatures. Based on the drying requirements of 4-trifluoromethylnicotinic acid in different areas of the inner cavity 17, the dry gases entering different air chambers 13 can be differentiated, thereby improving the drying effect and quality of 4-trifluoromethylnicotinic acid.

[0048] For example, when the initial moisture content of 4-trifluoromethylnicotinic acid is high, or the material is relatively densely packed and difficult to dry, the temperature of the drying gas introduced into the air chamber 13 near the inlet 14 (using end-entry air) can be set higher. However, since the material in the inner cavity 17 at the top of the air chamber 13 near the outlet 15 (using side-entry air) has already undergone a certain degree of drying, the temperature of the drying gas introduced into this air chamber 13 can be set lower than that of the end-entry air chamber 13. This can reduce the adverse effects of excessively high temperature on the material properties and also save energy.

[0049] See Figure 3 and combined Figure 4As shown, the drive mechanism 3 adopts a multi-point structure design, including multiple support rods 31. These support rods 31 are respectively arranged at the end corners of the two air chambers 13, and each support rod 31 is equipped with a cylinder 32. The cylinder body of the cylinder 32 is fixed on the lower fixed bed plate 21, and its push rod end is connected to the bottom of the upper movable bed plate 22 to realize the striking action of the movable bed plate 22. At the same time, for the end air chamber 13, the support rod 31 near the air inlet end is extended to directly affect the airflow state in the air chamber 13. The support rod 31 is located at the four corners of the air chamber 13, which can break the airflow dead corners that are easily formed in the corners of the air chamber 13 and reduce the airflow stagnation in the corners. The support rod 31 extended in the end air chamber 13 can guide the dry gas entering from the end, guide the airflow to flow smoothly along the preset path, reduce the turbulence caused by airflow impact, and make the dry gas pass through the bed structure 2 more efficiently into the inner cavity 17, ensuring the stability of the fluidization state.

[0050] Combination Figure 5 and Figure 6 As shown, during operation, the 4-trifluoromethylnicotinic acid to be dried is fed into the inner cavity 17 of the fluidized bed equipment body 1 through the feed port 14 located above the side wall of the bed body 12. The cylinder 32 can drive the movable bed plate 22 to periodically strike the fixed bed plate 21 below to generate mechanical impact force. Among the materials fed into the inner cavity 17, the lighter part is carried by the drying airflow blown in from the air chamber 13 and is in a fluidized boiling state in the inner cavity 17, while the water-containing clumps of 4-trifluoromethylnicotinic acid fall onto the upper surface of the movable bed plate 22 due to their own weight, thus achieving the separation of light and heavy materials. With targeted treatment, after the cylinder 32 is started, it drives the movable bed plate 22 to perform a periodic reciprocating striking motion relative to the fixed bed plate 21. This motion acts on the surface of the movable bed plate 22 to break up the clumps of water-containing clumps and disperse them into fine particles. On the other hand, the impact force acts on the fixed bed plate 21 to shake off the material blocking its first air hole 23 to maintain the air passage. After being broken by the striking, the 4-trifluoromethyl nicotinic acid block is lighter in weight and is carried away from the bed structure 2 by the rising drying airflow, ensuring the orderly progress of the drying process.

[0051] The movable bed board 22 has a lightweight structure, including an aluminum alloy frame and an elastic cushioning layer. The elastic cushioning layer is located at the bottom of the movable bed board 22 and provides cushioning when the movable bed board 22 is in contact with the fixed bed board 21. Figure 7The movable bed board 22 adopts an overall lightweight structure design, which includes an aluminum alloy frame and an elastic buffer layer. The aluminum alloy frame serves as the main support structure of the movable bed board 22, and the elastic buffer layer is fixedly installed at the bottom of the movable bed board 22. The elastic buffer layer is made of nitrile rubber and can directly act on the contact surface of the movable bed board 22 when it is driven downward by the drive mechanism 3 and comes into contact with the fixed bed board 21 below, so as to play a buffering role.

[0052] Specifically, the lightweight aluminum alloy frame of the movable bed board 22 reduces the load on the drive mechanism 3 when it performs periodic reciprocating striking motions, thus reducing drive energy consumption. At the same time, it ensures the response speed of the striking action of the movable bed board 22. The nitrile rubber elastic buffer layer at the bottom can absorb the impact force generated by the contact between the movable bed board 22 and the fixed bed board 21, avoiding direct collision between metal materials that could cause wear on the bed board structure and extending the service life of the fixed bed board 21 and the movable bed board 22. In addition, the buffering effect can reduce the impact of bed board vibration on the airflow stability in the air chamber 13 during the striking process, ensuring that the drying airflow continuously and evenly passes through the first air hole 23 of the fixed bed board 21, thus ensuring the fluidized drying effect of 4-trifluoromethylnicotinic acid.

[0053] Because 4-trifluoromethylnicotinic acid powder is prone to sticking together during the drying process due to moisture or temperature changes, and because the movable bed plate 22 periodically taps the fixed bed plate 21, material residue is easily accumulated on the surface of the bed structure 2. Therefore, both the fixed bed plate 21 and the movable bed plate 22 are coated with a non-stick material coating. This reduces the adhesion of 4-trifluoromethylnicotinic acid powder or agglomerated material to the surface of the bed structure 2, reduces material residue accumulation on the surface of the bed structure 2, and ensures that the movable bed plate 22 can effectively act on the agglomerated material when tapping, thus improving the crushing efficiency. At the same time, the non-stick material coating reduces the adhesion of material to the inner wall of the first air hole 23 of the fixed bed plate 21, reduces the risk of air hole blockage, and allows the drying airflow to smoothly pass through the air chamber 13 and enter the inner cavity 17 from the bed structure 2. This non-stick material coating can be made of polytetrafluoroethylene (PTFE), which has high temperature resistance and an extremely low surface friction coefficient, effectively reducing the adhesion of 4-trifluoromethylnicotinic acid powder and agglomerated material to the bed plate surface.

[0054] 4-Trifluoromethylnicotinic acid easily forms hard or large lumps after it clumps together. If the material is lifted by the up-and-down movement of the movable bed plate 22 and then crushed by its own weight, some of the clumps may not be crushed sufficiently, resulting in insufficient crushing efficiency. Therefore, the upper surface of the movable bed plate 22 is provided with a protrusion structure 25 to assist in crushing the clumps.

[0055] like Figure 7As shown, the protrusion structure 25 on the upper surface of the movable bed plate 22 can form multi-point contact with the agglomerated material when the movable bed plate 22 makes periodic reciprocating striking motion, concentrating the mechanical impact force generated by the striking on the local area of ​​the agglomerated material, making it easier for the agglomerated material to crack and disperse, and improving the crushing effect on agglomerated materials with high hardness or large volume.

[0056] See Figure 8 and combined Figure 9 As shown, the first air hole 23 is a trumpet-shaped hole, and its diameter at the end near the air chamber 13 is larger than the diameter at the end near the inner cavity 17.

[0057] The trumpet-shaped structure of the first vent 23 increases the velocity of the drying airflow entering from the air chamber 13 as it passes through the gradually narrowing vent outlet, forming a high-speed airflow (based on the continuity equation in fluid mechanics). This high-speed airflow enhances the initial impact force on the material inside the inner cavity 17, helps disperse slightly agglomerated materials, and simultaneously increases the lifting force on unagglomerated light materials, ensuring they remain stably in a fluidized boiling state. Furthermore, the larger diameter of the trumpet-shaped vent near the end of the air chamber 13 provides better conduction space for the impact force generated by the vibration of the movable bed plate 22, which, combined with the high-speed airflow... The reverse force can more efficiently shake off the blockage material stuck in the first air hole 23, reducing the probability of air hole blockage. It should be noted that the flow direction of the drying airflow is from the air chamber 13 to the inner cavity 17. When the material blocked in the first air hole 23 is shaken off by the movable bed plate 22, affected by the airflow direction, these shaken-off materials will move towards the inner cavity 17 with the airflow. Even if a very small amount of material falls into the air chamber 13, it will not affect the normal function of the air chamber 13 in storing and transporting the drying airflow, and will not interfere with the stable supply of subsequent drying airflow to the bed structure 2.

[0058] After 4-trifluoromethylnicotinic acid enters the inner cavity 17, it may be unevenly distributed due to airflow disturbance, or because of its light weight, it may be directly carried to the upper part of the inner cavity 17 by the airflow after being added, making it unable to contact the bed structure 2 and difficult to participate in the subsequent crushing and fluidized drying processes, thus affecting the drying effect. Therefore, a guide plate 4 is inclinedly installed inside the inner cavity 17. The guide plate 4 is a mesh plate structure. The high end of the guide plate 4 is connected to the inner wall of the inner cavity 17, and its height is higher than the feed inlet 14. The low end of the guide plate 4 extends to the top of the bed structure 2, forming a guide cavity 41 between the guide plate 4 and the bed structure 2. The height of the low end of the guide plate 4 is higher than the highest position that the movable bed plate 22 can reach during the crushing motion.

[0059] like Figure 5 and Figure 6As shown, the guide plate 4 is an inclined mesh plate, and its higher end is higher than the feed inlet 14. It can guide the 4-trifluoromethylnicotinic acid blocks fed from the feed inlet 14 into the guide cavity 41, and intercept the 4-trifluoromethylnicotinic acid blocks that have agglomerated but are relatively light. The intercepted material will slide along the inclined surface of the guide plate 4 to the lower end, and finally flow to the top of the bed structure 2. At the same time, the guide plate 4 is a mesh plate structure, which allows the drying airflow and 4-trifluoromethylnicotinic acid powder to pass through normally without obstructing the airflow and powder from entering the inner cavity 17. It can also play a preliminary dispersing role in the material during the sliding process, reducing the direct entry of large clumps into the inner cavity 17. In addition, the height of the lower end of the guide plate 4 is set higher than the highest position that the movable bed plate 22 can reach during the tapping motion, so as to avoid the collision between the movable bed plate 22 and the guide plate 4 when it moves.

[0060] The guide cavity 41, formed by the guide plate 4 and the bed structure 2, is located above the air chamber 13 at the end of the air inlet. Combined with the relatively high temperature airflow of the air chamber 13, the agglomerated 4-trifluoromethyl nicotinic acid blocks are further dried.

[0061] The driving mechanism 3 drives the movable bed board 22 to strike at a frequency of 1-10Hz and with an amplitude of 5-50mm.

[0062] Regarding the impact frequency, a lower frequency limit of 1Hz ensures that the movable bed plate 22 can continuously mechanically impact the agglomerated material within the impact interval, preventing agglomeration due to excessively long intervals, while providing sufficient time for the airflow to carry and disperse the material. A higher frequency limit of 10Hz prevents the light material in the bed from being excessively thrown out of the airflow's range due to high-frequency vibration, reducing irregular collisions and residues of material on the cavity wall, and avoiding excessive wear or structural resonance caused by high-frequency collisions between the drive mechanism 3 and the fixed bed plate 21. This range allows the impact to effectively break up agglomerates and clear pores, while also maintaining a stable fluidization environment in conjunction with the drying airflow, balancing crushing efficiency and equipment operational stability.

[0063] Regarding the amplitude, a lower limit of 5mm ensures that the impact force is transmitted to the surface of the fixed bed plate 21 and the blockage material in the first air hole 23, generating sufficient impact force to break the adhesion between materials and avoid the inability to effectively disperse agglomerates and the incomplete unblocking of air holes due to insufficient amplitude. An upper limit of 50mm prevents the movable bed plate 22 from colliding with the guide plate 4 at the high end or the side wall of the inner cavity 17 during movement, while also avoiding excessive amplitude that would cause the bed material to be excessively lifted, resulting in an imbalance between the lifting and drying effects of the drying airflow on the material.

[0064] Working principle:

[0065] First, the external drying gas enters the two gas chambers 13 of the fluidized bed equipment body 1 through two methods: end gas inlet and side gas inlet. The temperature of the drying gas introduced into the two gas chambers 13 can be differentiated according to the drying requirements of 4-trifluoromethylnicotinic acid in different areas of the inner cavity 17: the end gas inlet gas chamber 13 near the feed port 14 can be introduced with higher temperature drying gas to treat materials with high initial moisture content or dense packing, while the side gas inlet gas chamber 13 near the discharge port 15 can be introduced with lower temperature drying gas to avoid damage to the preliminarily dried material due to high temperature and to save energy.

[0066] Subsequently, the 4-trifluoromethylnicotinic acid to be dried is fed into the inner cavity 17 through the feed port 14. Combined with the inclined mesh structure guide plate 4 in the inner cavity 17, the fed material will be received and the agglomerated material will be intercepted. However, the lighter material agglomerated material will fall directly onto the bed structure 2 due to its own weight without guidance. The material is guided to slide along the inclined surface to the top of the bed structure 2. At the same time, the drying airflow and material powder are allowed to pass through. This does not hinder the airflow, but can initially disperse the material and reduce the large agglomerated material from directly entering the inner cavity 17. Moreover, the guide cavity 41 is located above the end air inlet chamber 13, which can be combined with the relatively high temperature airflow of the chamber 13 to initially dry the agglomerated material.

[0067] Next, cylinder 32 drives movable bed plate 22 to periodically strike fixed bed plate 21: on the one hand, the protruding structure 25 on the upper surface of movable bed plate 22 makes multi-point contact with the agglomerated material, concentrating the impact force on the local part of the material, breaking up the water-containing agglomerated material and dispersing it into fine particles; on the other hand, the impact force generated by the strike can shake off the material blocked in the funnel-shaped first air hole 23 of fixed bed plate 21, maintaining the air passage unobstructed, and the elastic buffer layer can absorb the impact force of the bed plate collision, avoid structural wear and reduce the impact of vibration on airflow stability, further ensuring the unobstructed air hole and the striking crushing effect.

[0068] Finally, the agglomerated and broken materials, as well as the material particles whose mass has been reduced after being crushed by the moving bed plate 22, will also be carried by the rising high-speed airflow, participate in fluidization and boiling, and fully contact with the drying gas to complete the drying process of 4-trifluoromethylnicotinic acid.

[0069] Example 2: This example is based on the content provided in Example 1, and its purpose is to provide a drying process for 4-trifluoromethylnicotinic acid. The specific steps are as follows:

[0070] Step 1: The 4-trifluoromethylnicotinic acid to be dried is fed into the inner cavity 17 of the fluidized bed equipment body 1 through the feed port 14 located above the side wall of the bed body 12;

[0071] Step 2: In the material, the lighter parts are carried by the dry airflow blown in from the air chamber 13 and are in a fluidized boiling state in the inner cavity 17. In the material, the water-containing clumps of 4-trifluoromethyl nicotinic acid fall or slide down through the inclined guide plate 4 and finally reach the upper surface of the movable bed plate 22.

[0072] Step 3: The drive mechanism 3 is started, driving the movable bed plate 22 to perform a periodic reciprocating striking motion relative to the fixed bed plate 21 below. The striking motion can break up the clumps of material accumulated on the upper surface of the movable bed plate 22, and at the same time, the impact force shakes off the material blocking the first air hole 23 of the fixed bed plate 21, keeping the air passage unobstructed.

[0073] Step 4: After being crushed by impact, the 4-trifluoromethylnicotinic acid block becomes lighter and is carried away from the bed structure 2 by the rising drying airflow, entering the inner cavity 17 to participate in fluidization and boiling and complete the drying process.

[0074] Step 5: After drying, 4-trifluoromethylnicotinic acid is discharged through outlet 15, and the airflow in the inner cavity 17 is discharged from gas outlet 16.

[0075] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A continuous fluidized bed drying device for 4-trifluoromethylnicotinic acid, comprising a fluidized bed device body (1), which is composed of a base frame (11) and a bed body (12), wherein the interior of the bed body (12) forms an inner cavity (17); The bottom of the bed (12) is provided with a gas chamber (13) for introducing dry gas; The bed body (12) has an inlet (14) for feeding materials on one side wall and an outlet (15) on the other side wall, characterized in that: A gas outlet (16) is provided at the top of the inner cavity (17) near the discharge port (15). The inner cavity (17) is provided with a bed structure (2), which includes: A fixed bed board (21) is fixedly installed in the lower part of the inner cavity (17). The fixed bed board (21) has a plurality of first air holes (23) penetrating its upper and lower surfaces. The movable bed board (22) is movably mounted above the fixed bed board (21) via a drive mechanism (3). The movable bed board (22) has a second air hole (24) corresponding to the first air hole (23). The diameter of the second air hole (24) is larger than that of the first air hole (23). The drive mechanism (3) is used to drive the movable bed board (22) to perform reciprocating striking motion on the fixed bed board (21) in order to break up the agglomerated material falling on it and clear the first air hole (23).

2. The 4-trifluoromethylnicotinic acid continuous fluidized bed drying equipment according to claim 1, characterized in that: The air chamber (13) is provided in two parts, one of which is an end air inlet and the other air chamber (13) is a side air inlet; The drive mechanism (3) has a multi-point structure, including multiple support rods (31). The multiple support rods (31) are located at the end corners of the two air chambers (13). Each of the multiple support rods (31) is equipped with a cylinder (32), the cylinder body is fixed on the fixed bed board (21), and the end of its push rod is connected to the bottom of the movable bed board (22).

3. The 4-trifluoromethylnicotinic acid continuous fluidized bed drying equipment according to claim 2, characterized in that: The movable bed board (22) has a lightweight structure, including an aluminum alloy frame and an elastic buffer layer. The elastic buffer layer is located at the bottom of the movable bed board (22) and provides a buffering effect when the movable bed board (22) is in contact with the fixed bed board (21).

4. The 4-trifluoromethylnicotinic acid continuous fluidized bed drying equipment according to claim 3, characterized in that: The surfaces of both the fixed bed board (21) and the movable bed board (22) are coated with a non-adhesive material coating.

5. The 4-trifluoromethylnicotinic acid continuous fluidized bed drying equipment according to claim 4, characterized in that: The upper surface of the movable bed board (22) is provided with a protrusion structure (25) for assisting in breaking up agglomerated materials.

6. The 4-trifluoromethylnicotinic acid continuous fluidized bed drying equipment according to claim 1, characterized in that: The first air hole (23) is a trumpet-shaped hole, and the diameter of the hole near the end of the air chamber (13) is larger than the diameter of the hole near the end of the inner cavity (17).

7. The 4-trifluoromethylnicotinic acid continuous fluidized bed drying equipment according to claim 1, characterized in that: A guide plate (4) is inclinedly arranged inside the inner cavity (17). The guide plate (4) is a mesh structure. The high end of the guide plate (4) is connected to the inner wall of the inner cavity (17) and its height is higher than the feed inlet (14). The low end of the guide plate (4) extends to the top of the bed structure (2). A guide cavity (41) is formed between the guide plate (4) and the bed structure (2).

8. The 4-trifluoromethylnicotinic acid continuous fluidized bed drying equipment according to claim 7, characterized in that: The height of the lower end of the guide plate (4) is higher than the highest position that the movable bed board (22) can reach during the striking motion.

9. The 4-trifluoromethylnicotinic acid continuous fluidized bed drying equipment according to claim 1, characterized in that: The driving mechanism (3) drives the movable bed board (22) to strike at a frequency of 1-10Hz and with an amplitude of 5-50mm.

10. A drying process for 4-trifluoromethylnicotinic acid, characterized in that, The 4-trifluoromethylnicotinic acid continuous fluidized bed drying equipment according to any one of claims 1-9 includes the following method steps: S1. The 4-trifluoromethylnicotinic acid to be dried is fed into the inner cavity (17) of the fluidized bed equipment body (1) through the feed port (14) located above the side wall of the bed body (12); S2. In the material, the lighter weight is carried by the dry airflow blown in from the air chamber (13) and is in a fluidized boiling state in the inner cavity (17). In the material, the water-containing clumps of 4-trifluoromethyl nicotinic acid fall or slide down through the inclined guide plate (4) and finally reach the upper surface of the movable bed plate (22). S3. The drive mechanism (3) is started, driving the movable bed plate (22) to perform a periodic reciprocating striking motion relative to the fixed bed plate (21) below. The striking motion can break up the clumps of material accumulated on the upper surface of the movable bed plate (22), and at the same time, the impact force shakes off the material blocked in the first air hole (23) of the fixed bed plate (21), keeping the air passage unobstructed. S4. After being crushed by impact, the 4-trifluoromethylnicotinic acid block becomes lighter and is carried away from the bed structure (2) by the rising drying airflow, enters the inner cavity (17) to participate in fluidization and boiling and complete the drying process. S5. After drying, 4-trifluoromethylnicotinic acid is discharged through the outlet (15), and the airflow in the inner cavity (17) is discharged from the gas outlet (16).

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