Extrusion and delivery device for a new denitration catalyst
By combining a twin-screw screw and a vibrating table, the problems of bubble formation and pressure instability caused by uneven stress on raw materials in the production of denitrification catalysts were solved, and high-quality production of catalyst preforms was achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HENAN KANGNINGTE ENVIRONMENTAL PROTECTION TECH CO LTD
- Filing Date
- 2025-05-12
- Publication Date
- 2026-06-12
AI Technical Summary
In the current production of denitrification catalysts, the raw materials are prone to bubbles and surface pits due to uneven force when falling into the screw, and the extrusion pressure is unstable, resulting in a decrease in product yield.
The extrusion discharge device uses a combination of a twin-screw extruder and a vibrating table. The vibrating table disperses the raw material particles and discharges the gas, while the twin-screw extrudes and compresses the raw material. Combined with bottom and top storage tanks, it stabilizes the raw material supply and ensures stable extrusion pressure.
It effectively reduces internal bubbles and surface defects in the catalyst preform, improves the stability of extrusion pressure, and increases product yield.
Smart Images
Figure CN224348496U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of denitrification catalyst production equipment, specifically a novel extrusion and export device for denitrification catalyst. Background Technology
[0002] Denitrification catalysts are mainly used to remove nitrogen oxides (NOx) from industrial emissions. The catalyst promotes chemical reactions, converting harmful NOx into harmless nitrogen gas and water vapor, thus effectively reducing environmental pollution. The production of denitrification catalysts involves mixing raw materials such as titanium dioxide (TiO2), vanadium pentoxide (V2O5), and tungsten trioxide (WO3) in a specific ratio, then adding appropriate additives (such as binders and pore-forming agents) and solvents (usually water), and placing the mixture in a mixing device (such as a twin-screw extruder). The rotation and stirring of the screws ensure thorough and uniform mixing of the raw materials, additives, and solvents, forming a slurry with good plasticity and flowability. This slurry is then fed into an extruder using a specialized die, and extruded under pressure through the die's channels to form a catalyst preform. During the extrusion process, parameters such as extrusion pressure, speed, and temperature must be strictly controlled to ensure the dimensional accuracy and shape integrity of the preform. However, in the production of existing denitrification catalysts, the extrusion discharge device generally has only one feed box. The raw material poured into the box falls directly onto the screw, which causes some problems. On the one hand, because the raw material is viscous, it will roll and deform due to uneven force when falling in, which may trap air and cause air to fall with it, resulting in air bubbles inside the extruded catalyst preform or pits on the surface. On the other hand, because the raw material is viscous, it has fluidity. Therefore, the more raw material inside the box, the greater the bottom pressure. Unstable extrusion pressure of the catalyst preform can lead to product deformation or uneven wall thickness, cracking during subsequent drying or sintering, and other problems, reducing the yield. Utility Model Content
[0003] (a) Technical problems to be solved
[0004] To address the shortcomings of existing technologies, this invention provides a novel extrusion and discharge device for denitrification catalysts, which solves the problems mentioned in the background section.
[0005] (II) Technical Solution
[0006] To achieve the above objectives, this utility model is implemented through the following technical solution: a novel extrusion discharge device for denitrification catalyst, comprising a bottom feeding box and a top storage box. A spiral sleeve is installed on one side of the bottom feeding box, and an extrusion die is installed at one end of the spiral sleeve. A double spiral screw is installed inside the spiral sleeve and the bottom feeding box. A motor for driving the double spiral screw to rotate is installed on the other side of the bottom feeding box. A box cover is installed on the top of the bottom feeding box. A feed pipe is fixedly installed on the top of the box cover near the motor. A front hose is sleeved on the other end of the feed pipe. A discharge pipe is fixedly installed on one side below the top storage box. A rear hose is sleeved on the other end of the discharge pipe. A vibration sleeve is provided between the rear hose and the front hose. A vibration table for driving the vibration sleeve is installed below the vibration sleeve. Return pipes communicating with the top of the top storage box are installed on both sides of the box cover near the feed pipe.
[0007] Preferably, the bottom of the bottom feeding box is an arc-shaped bottom with a radius larger than that of the spiral sleeve, and the arc-shaped bottom is concentric with the spiral sleeve.
[0008] Preferably, the front and rear sections of the twin-helix screw are respectively provided with two types of helical blades with different radii. The front section helical blades with smaller radii are located inside the helical sleeve and in the front part of the bottom feed box, while the rear section helical blades with larger radii are located in the rear part of the bottom feed box.
[0009] Preferably, a transparent tempered glass is installed above the box cover near the feed pipe. The width of the transparent tempered glass is small, but the length is large, only slightly smaller than the width of the box cover.
[0010] Preferably, the feed pipe is a right-angle bend, with the lower end of the feed pipe located directly above the double-helix screw, and the upper end of the feed pipe being concentric with the discharge pipe and having the same radius.
[0011] Preferably, the top of the bottom feed box is a V-shape that gradually widens upwards, making it wider at the top and narrower at the bottom, and has a certain height. The distance between the two return pipes is greater than the diameter of the lower double helical screw, so that the lower end of the return pipe is not located directly above the double helical screw.
[0012] This invention provides a novel extrusion and discharge device for denitrification catalyst, which has the following beneficial effects:
[0013] 1. The extrusion and discharge device of this novel denitrification catalyst, through the combination of a twin-screw screw and a vibrating table, enables the extrusion and discharge device of this novel denitrification catalyst to greatly reduce the presence of air bubbles inside the catalyst blank or pits on its surface. The vibrating table can disperse and rearrange the raw material particles, reducing the gaps between particles and expelling air. The twin-screw screw can further disperse the raw material and expel it forward, allowing the air clumps that have not been expelled after vibration to be released further outward, thereby reducing the air in the raw material and thus greatly reducing the presence of air bubbles inside the catalyst blank or pits on its surface.
[0014] 2. The extrusion discharge device of this novel denitrification catalyst, through the coordinated arrangement of a bottom feeding box, a top storage box, and a twin-screw extruder, achieves a significant improvement in the stability of the catalyst preform extrusion pressure, thereby increasing the yield. Because it has two boxes connected by a horizontal pipe, the pressure at the raw material inlet of the screw extrusion device does not change with the amount of raw material input. Instead, it is determined by the thrust provided by the rear end of the twin-screw extruder and the viscosity of the raw material. Since the viscosity of the same batch of raw material remains essentially constant, the extrusion pressure will remain relatively constant as long as the twin-screw speed remains unchanged. Furthermore, due to the high speed precision of existing motors, the stability of the catalyst preform extrusion pressure is also very high, thus greatly improving the yield. Attached Figure Description
[0015] Figure 1 This is a structural schematic diagram of the three-dimensional view of this utility model;
[0016] Figure 2 This is a structural schematic diagram of the main view of this utility model;
[0017] Figure 3 This is a top view of the structure of this utility model;
[0018] Figure 4 This is a structural schematic diagram of the cross-sectional view of this utility model.
[0019] In the diagram: 1. Bottom feed box; 2. Top storage box; 3. Spiral sleeve; 4. Extrusion die; 5. Twin spiral screw; 6. Motor; 7. Box cover; 8. Feed pipe; 9. Front hose; 10. Discharge pipe; 11. Rear hose; 12. Vibration sleeve; 13. Vibration table; 14. Return pipe; 15. Transparent tempered glass. Detailed Implementation
[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.
[0021] Please see Figures 1 to 4This utility model provides a technical solution: a novel extrusion and discharge device for denitrification catalyst, comprising a bottom feeding box 1 and a top storage box 2. The volume of the top storage box 2 is much larger than that of the bottom feeding box 1. The top storage box 2 is a component for temporary storage of raw materials. The bottom feeding box 1 is a direct feeding component of a screw feeding structure. A spiral sleeve 3 is installed on one side of the bottom feeding box 1. The bottom of the bottom feeding box 1 is an arc bottom with a radius larger than that of the spiral sleeve 3, and the arc bottom is concentric with the spiral sleeve 3. An extrusion die 4 is installed at one end of the spiral sleeve 3. The denitrification catalyst is extruded and formed in the extrusion die 4. A double spiral screw 5 is installed inside the spiral sleeve 3 and the bottom feeding box 1. A driving double spiral screw 5 is installed on the other side of the bottom feeding box 1. The screw 5 is rotated by a motor 6. The front and rear sections of the double-helix screw 5 are respectively equipped with two types of spiral blades with different radii. The front spiral blades with smaller radii are located inside the spiral sleeve 3 and in the front part of the bottom feeding box 1, while the rear spiral blades with larger radii are located in the rear part of the bottom feeding box 1. The rear spiral blades can further mix the raw materials evenly and push and squeeze the raw materials behind the bottom feeding box 1 forward. On the one hand, it can actively provide a certain pressure of raw materials to the feed port of the spiral sleeve 3, and on the other hand, it can break up and change the position of air bubbles in the raw materials and squeeze them out. A box cover 7 is installed on the top of the bottom feeding box 1. A feed pipe 8 is fixedly installed on the top of the box cover 7 near the side of the motor 6. A transparent tempered glass 15 is installed on the top of the box cover 7 near the feed pipe 8. The transparent tempered glass 15 is relatively small in width but relatively large in length, only slightly smaller than the width of the lid 7. Through the transparent tempered glass 15, the material inside the bottom feeding box 1 can be observed. The feed pipe 8 is a right-angle bend, with its lower end located directly above the double-spiral screw 5, allowing the material to fall directly from the feed pipe 8 onto the double-spiral screw 5. The upper end of the feed pipe 8 is concentric with the discharge pipe 10 and has the same radius. The other end of the feed pipe 8 is fitted with a front flexible hose 9. A discharge pipe 10 is fixedly installed on one side below the top storage box 2, with a rear flexible hose 11 fitted at the other end. A vibration sleeve 12 is installed between the rear flexible hose 11 and the front flexible hose 9. The discharge pipe 10, feed pipe 8, and vibration sleeve 12 are all in a horizontal position, ensuring the top storage box 2... The weight of the raw material inside the material bin 2 does not directly press on the vibrating sleeve 12, thus reducing the external force on the vibrating sleeve 12. A vibrating table 13 is installed below the vibrating sleeve 12 to drive it. When the vibrating table 13 is working, it can vibrate the raw material inside the vibrating sleeve 12. Vibration can disperse and rearrange the raw material particles and expel air. Return pipes 14 connected to the top of the top storage bin 2 are installed on both sides of the bin cover 7 near the feed pipe 8. The top of the bottom feed bin 1 is a V-shape that gradually widens upwards, making it wider at the top and narrower at the bottom, and has a certain height. The distance between the two return pipes 14 is larger than the diameter of the lower double helical screw 5, so that the lower end of the return pipe 14 is not directly above the double helical screw 5. Under normal circumstances, the return pipes 14 can expel the air discharged from the raw material.When there is too much material inside the bottom feed hopper 1, the material can be returned to the top storage hopper 2 to maintain stable pressure in the bottom feed hopper 1.
[0022] In use, the evenly mixed raw materials are first placed into the top storage bin 2. The amount added does not need to be precisely controlled. Due to the fluidity of the raw materials, they flow from the top storage bin 2 to the bottom supply bin 1 through the discharge pipe 10 under their own weight. During this process, the raw materials pass through the vibrating sleeve 12. When the vibrating table 13 is working, it vibrates the raw materials inside the vibrating sleeve 12. Under the vibration, the raw material particles are in a fluttering state, and the originally clumped cement particles are shaken apart and fully dispersed. At the same time, the various particles in the raw materials gain additional kinetic energy, enabling them to overcome the friction and viscosity between particles, thus allowing them to move and rearrange more freely, resulting in a more even distribution between particles. The material is uniformly packed and more tightly filled, thus reducing the gaps between particles. Vibration allows air in the raw material particles to rise to the surface and be expelled more easily, refilling the space previously occupied by air with raw material particles. The raw material entering the bottom feed box 1 falls directly onto the twin-helix screw 5. At this time, the air originally inside the bottom feed box 1 is discharged through the return pipe 14. When the bottom feed box 1 is full of raw material, the motor 6 can be started. When the motor 6 is working, it drives the twin-helix screw 5 to rotate. The front section of the twin-helix screw 5 has a small radius of spiral blades and is located inside the spiral sleeve 3 and in the front part of the bottom feed box 1, which can slowly feed the raw material from the bottom feed box 1 into the spiral sleeve 3. The rear section has a large radius of spiral blades and is located in the rear part of the bottom feed box 1. The material in the bottom feed box 1 can be pushed forward while being stirred. If the material viscosity is low, the speed at which it enters the bottom feed box 1 is greater than the speed at which it is extruded outwards. In this case, the material in the top storage box 2 will always fill the bottom feed box 1. Because the material viscosity is low, the pushing force of the rear spiral blades is also very small. Therefore, when the material viscosity is low, the pressure of the material at the inlet of the spiral sleeve 3 is the same as the pressure when the bottom feed box 1 is full. Since it is always full, the pressure is very stable. If the material viscosity is high, the speed at which it enters the bottom feed box 1 is less than the speed at which it is extruded outwards. In this case, the material in the top storage box 2 cannot fill the bottom feed box 1 by its own weight. Therefore, external force is required to assist the material. The material falls, for example, by adding compressed air above the top storage tank 2 to ensure the supply balance of raw materials in the bottom supply tank 1. At this time, the height of the raw materials in the bottom supply tank 1 will affect the pressure to a certain extent. However, because the viscosity of the raw materials is high, the thrust of the rear spiral blades pushing the raw materials forward is also relatively large. Therefore, the raw materials in the bottom supply tank 1 will be in a situation where the front is higher than the back. That is, the liquid level of the raw materials at the inlet of the spiral sleeve 3 will be higher than that at the back. At the same time, there is also the thrust provided by the double spiral screw 5. Therefore, even if the height of the raw materials is not constant at this time, the pressure remains relatively stable under the thrust of the double spiral screw 5. During this process, the workers can directly observe the situation of the raw materials in the bottom supply tank 1 through the transparent tempered glass 15.
[0023] In summary, the extrusion device of this novel denitrification catalyst disperses and rearranges raw material particles through the vibration table 13, reducing the gaps between particles and expelling air. The twin-screw 5 further disperses and extrudes the raw material, releasing any air clusters that were not expelled after vibration. This reduces air in the raw material and significantly reduces the presence of air bubbles or pits on the surface of the catalyst preform. Because there are two chambers connected by a horizontal pipe, the pressure at the raw material inlet of the screw extrusion device does not change with the amount of raw material input. Instead, it is determined by the thrust provided by the rear end of the twin-screw 5 and the viscosity of the raw material. Since the viscosity of the same batch of raw material remains essentially constant, the extrusion pressure will remain essentially constant as long as the rotational speed of the twin-screw 5 remains unchanged. Due to the high rotational speed accuracy of the existing motor 6, the stability of the catalyst preform extrusion pressure is also very high, which can greatly improve the yield.
[0024] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.
Claims
1. A novel extrusion discharge device for a denitrification catalyst, comprising a bottom feeding box (1) and a top storage box (2), characterized in that: A spiral sleeve (3) is installed on one side of the bottom feed box (1), and an extrusion die (4) is installed at one end of the spiral sleeve (3). A double spiral screw (5) is installed inside the spiral sleeve (3) and the bottom feed box (1). A motor (6) that drives the double spiral screw (5) to rotate is installed on the other side of the bottom feed box (1). A box cover (7) is installed on the top of the bottom feed box (1). A feed pipe (8) is fixedly installed on the top of the box cover (7) near the motor (6). The other end of 8) is fitted with a front hose (9), and a discharge pipe (10) is fixedly installed on one side below the top storage box (2). The other end of the discharge pipe (10) is fitted with a rear hose (11). A vibration sleeve (12) is provided between the rear hose (11) and the front hose (9). A vibration table (13) for driving the vibration sleeve (12) is installed below the vibration sleeve (12). A return pipe (14) connected to the top of the top storage box (2) is installed on both sides of the box cover (7) near the feed pipe (8).
2. The extrusion discharge device for the novel denitrification catalyst according to claim 1, characterized in that: The bottom of the bottom feeding box (1) is an arc bottom with a radius larger than that of the spiral sleeve (3), and the arc bottom is concentric with the spiral sleeve (3).
3. The extrusion discharge device for the novel denitrification catalyst according to claim 1, characterized in that: The front and rear sections of the double helical screw (5) are respectively equipped with two types of helical blades with different radii. The front section helical blade with a smaller radius is set inside the helical sleeve (3) and in the front part of the bottom feed box (1), while the rear section helical blade with a larger radius is set in the rear part of the bottom feed box (1).
4. The extrusion discharge device for the novel denitrification catalyst according to claim 1, characterized in that: A transparent tempered glass (15) is installed above the box cover (7) near the feed pipe (8). The width of the transparent tempered glass (15) is small, but the length is large, only slightly smaller than the width of the box cover (7).
5. The extrusion discharge device for the novel denitrification catalyst according to claim 1, characterized in that: The feed pipe (8) is a right-angle bend. The lower end of the feed pipe (8) is located directly above the double helical screw (5). The upper end of the feed pipe (8) is concentric with the discharge pipe (10) and has the same radius.
6. The extrusion discharge device for the novel denitrification catalyst according to claim 1, characterized in that: The bottom feed box (1) has a V-shape that gradually expands upwards, making it wider at the top and narrower at the bottom, and it has a certain height. The distance between the two return pipes (14) is greater than the diameter of the lower double helical screw (5), so that the lower end of the return pipe (14) is not located directly above the double helical screw (5).