Rotary kiln type deacidification equipment and treatment process for white carbon black deacidification

Abstract

The application discloses a rotary kiln type deacidification equipment for white carbon black deacidification, which comprises a deacidification assembly, a rotary assembly and an elastic vibration assembly, the deacidification assembly is used for desorbing HCL from the surface of powder, and then continuously taking away acid gas through airflow, and uniform heating and deep deacidification are realized by relying on rotation, the rotary assembly is used for driving the rotary kiln body pipeline to continuously reciprocating rotate, and the elastic vibration assembly is used for intermittently knocking and vibrating the rotary kiln wall by the reciprocating rotation of the rotary kiln itself to prevent material from adhering to the wall. The application also discloses a processing technology of the rotary kiln type deacidification equipment for white carbon black deacidification, which comprises the following steps: step one, pretreatment of feeding; step two, equipment starting and parameter debugging; step three, high-temperature deacidification reaction; step four, material discharging and conveying; step five, tail gas treatment and powder recovery; and step six, equipment anti-sticking and anti-condensation guarantee.

Description

Technical Field

[0001] This invention relates to the field of deacidification equipment technology, and in particular to rotary kiln type deacidification equipment and processing technology for deacidification of silica. Background Technology

[0002] Currently, the most mature deacidification furnace used in the fumed silica industry is the fluidized bed type. Air is introduced from the bottom of the equipment and typically heated to over 500°C. This hot air fluidizes the relatively lightweight fumed silica. A certain amount of steam, or a certain amount of natural gas / hydrogen, is also introduced for combustion. The high-temperature water vapor generated by the combustion of the air-steam or combustible gas flows along the equipment's structure (single-stage or multi-stage series), allowing the fumed silica to remain in the fluidized state for a specific residence time. During this process, the high temperature above 500°C not only evaporates surface water adsorbed on the silica layer but also breaks down the silanol groups formed during the high-temperature hydrolysis and aggregation stages of the fumed silica, causing the structural water formed by the hydroxyl groups to be released. Simultaneously, chlorine adhering to the silica surface is removed by high-temperature hydrogen chloride and water vapor, thus improving the pH and moisture content of the silica.

[0003] For current rotary kiln-type deacidification equipment, fluidized bed deacidification furnaces introduce fluidizing air at the bottom to maintain powder fluidization. However, because the particle size of fumed silica aggregates is 4-46μm, which is relatively fine, slight changes in production load, fumed silica particle size, and fluidizing air can lead to bed instability. If the bed is too low, the deacidification effect is unstable; if the bed is too high, there is a risk of fumed silica material loss. Furthermore, the unidirectional rotation of the rotary kiln results in insufficient internal material contact area. Therefore, this invention proposes a rotary kiln-type deacidification equipment and process for fumed silica deacidification. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a rotary kiln-type deacidification equipment and process for deacidification of silica.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A rotary kiln-type deacidification equipment for deacidification of silica includes a deacidification component, a rotary component, and a spring vibration component;

[0007] The deacidification component is used to desorb HCl from the powder surface and then continuously remove the acid gas through airflow. At the same time, it relies on rotation to achieve uniform heating and deep deacidification. The deacidification component includes a first base and a rotary kiln rotatably disposed on the top of the first base.

[0008] The rotary assembly is used to drive the rotary kiln body pipe to continuously reciprocate to maintain the full reaction of the internal material. The rotary assembly consists of a drive unit and a reciprocating unit. The drive unit is used to provide power for continuous intermittent reciprocating rotation. The drive unit includes a fixed chamber fixedly installed on the top of the first base.

[0009] The vibratory component is used to intermittently vibrate the rotary kiln tube wall by reciprocating the rotary kiln itself to prevent material from sticking to the wall. The vibratory component includes a second toothed ring fixedly installed on the outer wall of one side of the rotary kiln.

[0010] Preferably, a second base is fixedly provided on one side of the first base, a third base is fixedly provided on one side of the second base, a feed hopper is fixedly provided on one side of the rotary kiln, a steam port is fixedly provided on one side of the feed hopper, and a discharge hopper is fixedly provided on the other side of the rotary kiln.

[0011] Preferably, a discharge cyclone separator that communicates with the discharge hopper is fixedly installed on the top of the second base, and a bag filter that communicates with the discharge cyclone separator is fixedly installed on the top of the third base, with a flue gas fan that communicates with the bag filter fixedly installed on one side.

[0012] Preferably, a first fixing plate is fixedly installed inside the fixing chamber, and a plurality of fixing blocks are fixedly installed on the first fixing plate. A second fixing plate is fixedly installed on the top of each fixing block. A worm gear is rotatably connected between two fixing blocks. A worm wheel is rotatably connected to the side of the first fixing plate near the worm gear. A first bevel gear is fixedly connected to one side of the worm gear. A second bevel gear is rotatably connected to the side of the first fixing plate near the first bevel gear. A drive motor is fixedly installed below the fixing chamber and inside the first base. The drive end of the drive motor is fixedly connected to the second bevel gear.

[0013] Preferably, the reciprocating unit is used to drive the rotary kiln to perform continuous reciprocating rotation. The reciprocating unit includes a first gear rotatably connected to the top of the second fixed plate and fixedly connected to the worm gear. A second gear is rotatably connected to the side of the second fixed plate near the first gear. A first sector tooth is fixedly provided on the first gear, and a second sector tooth is fixedly provided on the second gear.

[0014] Preferably, a groove is fixedly provided on the top of the second fixed plate near the two fan-shaped teeth, a slider is slidably connected inside the groove, a first toothed plate is fixedly connected on the side of the slider near the two fan-shaped teeth, a second toothed plate is fixedly provided on the top of the slider, a fixed cylinder is fixedly provided on the top of the fixed chamber and communicates with it, the rotary kiln and the fixed cylinder are rotatably connected, and a first toothed ring is fixedly provided on the outer wall of the rotary kiln and inside the fixed cylinder.

[0015] Preferably, a first fixed column is fixedly installed on the first base, and a third gear is rotatably connected to the side of the first fixed column near the second gear ring. The third gear and the two sides of the first fixed column are respectively rotatably connected to a first elastic plate through a connecting rod. A third gear ring is fixedly installed on the outer wall of the other side of the rotary kiln. A second fixed column is fixedly installed on the first base, and a fourth gear is rotatably connected to the side of the second fixed column near the third gear ring. The fourth gear and the two sides of the second fixed column are respectively rotatably connected to a second elastic plate through a connecting rod.

[0016] Preferably, the worm and the worm wheel mesh with each other, the first bevel gear and the second bevel gear mesh with each other, the first gear and the second gear mesh with each other, the first sector tooth and the second sector tooth have opposite tooth orientations, the two sector teeth intermittently mesh with the first tooth plate through rotation, and the second tooth plate meshes with the first tooth ring.

[0017] Preferably, the second gear ring meshes with the third gear, the third gear ring meshes with the fourth gear, and the first elastic plate and the second elastic plate are elastic striking plate structures.

[0018] The processing technology of rotary kiln-type deacidification equipment for deacidification of silica includes the following steps:

[0019] Step 1: Feed pretreatment. After the fumed silica powder is cooled and agglomerated to 180-220℃, it is transported to the feed hopper of the rotary kiln. At the same time, steam is introduced through the steam port of the feed hopper. The ratio of steam to fumed silica feed is not less than 1:5, so that the powder and steam are initially mixed in the feed hopper.

[0020] Step 2: Equipment Start-up and Parameter Adjustment. Start the drive motor to drive the rotary assembly, making the rotary kiln rotate continuously at a speed of 1.5-2.5 r / min. At the same time, start the external heating equipment at the bottom of the rotary kiln and adjust the heating power through the thyristor to ensure that the temperature in the discharge hopper of the rotary kiln is stable at 500-520℃. Check the linkage status between the spring vibration assembly and the rotary kiln to ensure that the first and second spring plates can achieve intermittent vibration as the rotary kiln rotates.

[0021] Step 3: High-temperature deacidification reaction. After the mixture of fumed silica and steam enters the rotary kiln, the powder is fully dispersed by the reciprocating rotation of the rotary kiln and the dispersion effect of the multi-layer guide vanes inside the kiln. At the same time, relying on the uniform heat conduction of the external heating of the rotary kiln, the powder is kept at a temperature of 500-520℃ for 15-25 minutes in the kiln, allowing the chlorine on the surface of the powder to desorb and form hydrogen chloride, which combines with water vapor to form acid gas. The acid gas is continuously carried away from the surface of the powder by the airflow, completing the deep deacidification.

[0022] Step 4: Material discharge and conveying. After the deacidification reaction, the fumed silica powder from the deacidification process enters the discharge hopper of the rotary kiln. Ambient air (100-200 Nm³ / h) is introduced through the Venturi feeder at the bottom of the discharge hopper to convey the qualified powder to the subsequent packaging stage. The pH value of the powder after deacidification is controlled between 3.9 and 4.3, the moisture content is ≤0.8%, and the free chlorine content is ≤120 mg / kg.

[0023] Step 5: Tail Gas Treatment and Powder Recovery. The acidic high-temperature tail gas in the discharge hopper is discharged from the top and cooled to 180-220℃ by a cooler. It then enters the discharge cyclone separator and bag filter in sequence to collect the volatile silica powder that has escaped from the tail gas. The collected powder is then fed back to the rotary kiln feed hopper by a Venturi feeder with hot air (140℃, 80-100 Nm³ / h) to participate in the deacidification reaction again. The tail gas treated by the bag filter is discharged by a flue gas fan. By adjusting the variable frequency speed of the flue gas fan and the pipeline regulating valve, the pressure of the gas phase outlet pipeline of the rotary kiln feed cyclone separator is made to be 1.0-3.0 kPa higher than the pressure of the rotary kiln discharge hopper.

[0024] Step Six: Equipment Anti-sticking and Anti-condensation Protection. Throughout the entire deacidification process, the first and second elastic plates of the vibrating assembly intermittently vibrate the kiln tube wall as the rotary kiln rotates to prevent the gaseous silica powder from sticking to the wall. At the same time, the saturated steam coils of the cyclone separator entering and exiting the rotary kiln are kept heated (steam pressure not lower than 0.4MPa (G)), and the bag filter and pipelines, as well as the armored cable electric heating of the Venturi (temperature control 200±20℃), are kept heated to prevent acidic gas from condensing.

[0025] The present invention has the following beneficial effects:

[0026] 1. By setting up a drive unit, the drive unit adopts a transmission structure of drive motor, bevel gear, worm and worm wheel. The bevel gear realizes 90° conversion of power direction, and the worm and worm wheel structure has the characteristics of speed reduction and torque increase, and smooth transmission. It can convert the high-speed rotation of the drive motor into the low-speed stable rotation of the worm wheel, providing stable power for the low-speed rotation of the rotary kiln. At the same time, the self-locking characteristics of the worm and worm wheel can prevent the rotary kiln from reversing due to its own weight or material impact, thus improving the stability of equipment operation.

[0027] 2. By setting up a reciprocating unit, the reciprocating unit utilizes the linkage design of the first sector tooth, the second sector tooth, the first tooth plate, the second tooth plate, and the first tooth ring. The two sector teeth with opposite tooth orientations intermittently mesh with the first tooth plate, driving the slider to make reciprocating linear motion in the slide groove. Then, through the meshing of the second tooth plate and the first tooth ring, the linear motion is converted into the continuous reciprocating rotation of the rotary kiln. Compared with rotation in one direction, reciprocating rotation can subject the powder in the kiln to bidirectional centrifugal force and dispersion force. Combined with the action of the guide vanes in the kiln, the powder is more fully dispersed and the contact area with steam and high-temperature kiln wall is larger, avoiding the problem of incomplete deacidification caused by powder agglomeration, and achieving deep deacidification.

[0028] 3. By setting up a spring vibration assembly, the spring vibration assembly and the rotary kiln achieve linkage and self-drive. The rotation of the rotary kiln drives the second and third toothed rings on the outer wall to rotate synchronously, which in turn drives the meshing third and fourth gears to rotate. During the rotation of the gears, the first and second elastic plates on both sides make periodic elastic oscillations, realizing intermittent vibration of the rotary kiln tube wall. The first and second elastic plates are elastic impact plates. During the impact, the impact force generated by elastic deformation acts on the kiln tube wall, which can effectively shake off the fumed silica powder adhering to the tube wall. This avoids material loss caused by powder sticking to the wall and prevents problems such as excessive dehydroxylation and abnormal particle size caused by long-term heating of powder adhering to the wall, thus ensuring the uniformity of product quality. At the same time, the elastic impact will not cause hard impact on the kiln tube wall, avoiding equipment wear and extending the service life of the rotary kiln.

[0029] 4. The rotary kiln is a closed rotary structure. Compared with the open fluidization mode of traditional fluidized beds, it does not require the introduction of a large amount of fluidizing air. The material is transferred only by the steam and conveying gas necessary for the process. This avoids the problem of bed instability caused by changes in fluidizing air volume, powder particle size, and production load, and ensures the consistency of the deacidification reaction environment. At the same time, the external heating mode of the rotary kiln directly conducts heat to the kiln body, eliminating the need to heat the air first and then heat the material again. This greatly improves the heat transfer efficiency and reduces heat loss. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the main structure of the rotary kiln-type deacidification equipment for deacidification of silica proposed in this invention.

[0031] Figure 2 This is a side view of the rotary kiln-type deacidification equipment for deacidification of silica proposed in this invention.

[0032] Figure 3 This is a schematic diagram of the rotary kiln and the discharge cyclone separator in this invention;

[0033] Figure 4 This is a schematic diagram of the main structure of the rotary kiln in this invention;

[0034] Figure 5 This is a side view of the rotary kiln structure in this invention;

[0035] Figure 6 This is a schematic diagram of the structure of the rotary assembly in this invention;

[0036] Figure 7 This is a side view of the rotating assembly in this invention.

[0037] Figure 8 This is a schematic diagram of the internal structure of the fixed chamber and the fixed cylinder in this invention;

[0038] Figure 9 This is a schematic diagram of the drive unit in this invention;

[0039] Figure 10 This is a schematic diagram of the structure of one of the spring-vibration components in this invention;

[0040] Figure 11 This is a schematic diagram of another elastic vibration component in the present invention.

[0041] In the diagram: 1 First base, 2 Second base, 3 Third base, 4 Rotary kiln, 5 Feed hopper, 6 Steam inlet, 7 Discharge hopper, 8 Discharge cyclone separator, 9 Bag filter, 10 Flue gas fan, 11 Fixed hopper, 12 Fixed cylinder, 13 First fixed plate, 14 Second fixed plate, 15 Fixed block, 16 Worm gear, 17 Worm wheel, 18 First bevel gear, 19 Second bevel gear, 20 First gear, 21 Second gear, 22 First sector tooth, 23 Second sector tooth, 24 Slide groove, 25 Slider, 26 First toothed plate, 27 Second toothed plate, 28 First toothed ring, 29 Second toothed ring, 30 First fixed column, 31 Third gear, 32 First elastic plate, 33 Third toothed ring, 34 Second fixed column, 35 Fourth gear, 36 Second elastic plate, 37 Drive motor. Detailed Implementation

[0042] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0043] Example 1:

[0044] Reference Figures 1-3 A rotary kiln-type deacidification equipment for deacidification of silica, including a deacidification component, a rotary component and a spring vibration component;

[0045] The deacidification component is used to desorb HCl from the powder surface and then continuously remove acid gas through airflow. At the same time, it relies on rotation to achieve uniform heating and deep deacidification. The deacidification component includes a first base 1 and a rotary kiln 4 rotatably disposed on the top of the first base 1.

[0046] The rotary assembly is used to drive the kiln body pipe of the rotary kiln 4 to continuously reciprocate to maintain the full reaction of the internal material. The rotary assembly consists of a drive unit and a reciprocating unit. The drive unit is used to provide power for continuous intermittent reciprocating rotation. The drive unit includes a fixed chamber 11 fixedly installed on the top of the first base 1.

[0047] The vibratory assembly is used to intermittently vibrate the rotary kiln tube wall by reciprocating rotation of the rotary kiln 4 to prevent material from sticking to the wall. The vibratory assembly includes a second toothed ring 29 fixedly installed on the outer wall of one side of the rotary kiln 4.

[0048] A second base 2 is fixedly installed on one side of the first base 1, a third base 3 is fixedly installed on one side of the second base 2, a feed hopper 5 is fixedly installed on one side of the rotary kiln 4, a steam port 6 is fixedly installed on one side of the feed hopper 5, and a discharge hopper 7 is fixedly installed on the other side of the rotary kiln 4.

[0049] The top of the second base 2 is fixedly equipped with a discharge cyclone separator 8 that is connected to the discharge bin 7. The top of the third base 3 is fixedly equipped with a bag filter 9 that is connected to the discharge cyclone separator 8. A flue gas fan 10 connected to the bag filter 9 is fixedly installed on one side of the bag filter 9.

[0050] In this embodiment, the rotary kiln 4 adopts a closed kiln body pipeline structure and is rotatably installed in the fixed cylinder 12 at the top of the first base 1. Unlike the open fluidized bed structure of traditional fluidized beds, this rotary kiln 4 does not require the introduction of a large amount of fluidizing air. It only uses the steam and conveying gas necessary for the process to achieve material flow. This fundamentally avoids the problem of bed instability caused by slight changes in the amount of fluidizing air, the particle size of fumed silica (4-46μm), and the production load. It ensures the consistency of the deacidification reaction environment and completely solves the drawbacks of unstable deacidification effect when the fluidized bed is too low and material loss when the bed is too high. At the same time, the bottom of the rotary kiln 4 is equipped with external heating equipment and a heat insulation chamber. The heat insulation chamber is made of heat insulation material to completely wrap the kiln body and the heating equipment, so that the surface temperature of the outer heat insulation chamber does not exceed 50°C. The external heating equipment directly conducts heat to the kiln body, without the need to heat the air first and then heat the material again. This greatly improves the heat transfer efficiency, reduces heat loss, and lays the foundation for reducing the overall energy consumption of the subsequent equipment.

[0051] Furthermore, the feed hopper 5 is a fixed structure, connected to the feed end of the rotary kiln 4 through a high-temperature resistant sealing device, which can effectively prevent the leakage of powder and acidic gas. The steam port 6 is opened on the side wall of the feed hopper 5 and connected to the external steam conveying pipeline, which can precisely control the steam feed rate, so that the ratio of steam to fumed silica feed rate is not less than 1:5, providing a sufficient water vapor environment for chlorine desorption, ensuring that the hydrogen chloride formed by chlorine desorption on the powder surface can quickly combine with water vapor to form acid gas, and be continuously discharged with the airflow, thereby improving the deacidification efficiency. After the fumed silica powder is cooled and agglomerated to 180-220℃, it enters the feed hopper 5 and is initially mixed with steam in the feed hopper, which can pre-wet the powder, avoid local powder agglomeration in the kiln, and further improve the uniformity of deacidification.

[0052] Furthermore, the discharge cyclone separator 8, bag filter 9, and flue gas fan 10 are connected in series. The acidic high-temperature exhaust gas discharged from the discharge hopper 7 is cooled to 180-220℃ by a cooler before entering the discharge cyclone separator 8 for coarse separation, capturing large particles of loose powder. It then enters the bag filter 9 for fine separation. The bag filter 9 uses PTFE membrane filter bags, maintaining a filtration efficiency of over 99.9%, effectively capturing fine particles. The flue gas fan 10 is equipped with a variable frequency motor, whose speed can be adjusted in conjunction with the pipe... A regulating valve precisely controls the pressure of the gas phase outlet pipe of the rotary kiln feed cyclone separator to be 1.0-3.0 kPa higher than the pressure of the discharge hopper 7, preventing acid gas and powder from flowing back and ensuring the continuity of the deacidification reaction and tail gas discharge. In addition, Venturi feeders are installed below the discharge cyclone separator 8 and the bag filter 9, which can transport the collected scattered powder back to the feed hopper 5 of the rotary kiln 4 to participate in the deacidification reaction again, greatly improving the powder recovery rate, reducing material loss, and solving the problem of powder loss caused by the large amount of fluidized gas in traditional fluidized beds.

[0053] Example 2:

[0054] Reference Figures 4-9 Compared to Embodiment 1, in this embodiment, a first fixing plate 13 is fixedly installed inside the fixing chamber 11, and several fixing blocks 15 are fixedly installed on the first fixing plate 13. A second fixing plate 14 is fixedly installed on the top of the fixing blocks 15. A worm gear 16 is rotatably connected between two fixing blocks 15. A worm wheel 17 is rotatably connected to the side of the first fixing plate 13 near the worm gear 16. A first bevel gear 18 is fixedly connected to one side of the worm gear 16. A second bevel gear 19 is rotatably connected to the side of the first fixing plate 13 near the first bevel gear 18. A drive motor 37 is fixedly installed below the fixing chamber 11 and inside the first base 1. The drive end of the drive motor 37 is fixedly connected to the second bevel gear 19.

[0055] The reciprocating unit is used to drive the rotary kiln 4 to rotate continuously. The reciprocating unit includes a first gear 20 that is rotatably connected to the top of the second fixed plate 14 and fixedly connected to the worm gear 17. A second gear 21 is rotatably connected to the side of the second fixed plate 14 near the first gear 20. A first sector tooth 22 is fixedly provided on the first gear 20, and a second sector tooth 23 is fixedly provided on the second gear 21.

[0056] A groove 24 is fixedly provided on the top of the second fixed plate 14 near the two fan-shaped teeth. A slider 25 is slidably connected inside the groove 24. A first toothed plate 26 is fixedly connected on the side of the slider 25 near the two fan-shaped teeth. A second toothed plate 27 is fixedly provided on the top of the slider 25. A fixed cylinder 12 connected to the top of the fixed chamber 11 is fixedly provided. The rotary kiln 4 and the fixed cylinder 12 are rotatably connected. A first toothed ring 28 is fixedly provided on the outer wall of the rotary kiln 4 and inside the fixed cylinder 12.

[0057] The worm 16 meshes with the worm wheel 17, the first bevel gear 18 meshes with the second bevel gear 19, the first gear 20 meshes with the second gear 21, the first sector tooth 22 and the second sector tooth 23 have opposite tooth orientations, the two sector teeth intermittently mesh with the first tooth plate 26 through rotation, and the second tooth plate 27 meshes with the first tooth ring 28.

[0058] In this embodiment, when the drive unit is running, the drive motor 37 drives the second bevel gear 19 to rotate. The power direction is changed by 90° through the meshing of the first bevel gear 18 and the second bevel gear 19. Then, the speed reduction and torque increase are achieved through the meshing of the worm gear 16 and the worm wheel 17, converting the high-speed rotation of the drive motor 37 into the low-speed stable rotation of the worm wheel 17. The transmission structure of the worm gear has the characteristics of smooth transmission and strong self-locking. It can not only provide stable and continuous power for the low-speed rotation of the rotary kiln 4, but also prevent the rotary kiln 4 from reversing due to its own weight or material impact. This greatly improves the stability of equipment operation and avoids the problems of material accumulation and deacidification interruption caused by equipment reversal.

[0059] Furthermore, during the operation of the reciprocating unit, the worm gear 17 drives the first gear 20 to rotate. Through the meshing of the first gear 20 and the second gear 21, the second gear 21 is driven to rotate in the opposite direction, thereby driving the two sector teeth with opposite tooth openings to rotate synchronously. When the first sector tooth 22 meshes with the first tooth plate 26, it pushes the slider 25 to move linearly in one direction within the slide groove 24. When the first sector tooth 22 disengages from the first tooth plate 26 and the second sector tooth 23 meshes with the first tooth plate 26, it pushes the slider 25 to move linearly in the opposite direction within the slide groove 24. This cycle is repeated to achieve the reciprocating linear motion of the slider 25. The slider 25 drives the second tooth plate 27 to move linearly in the same direction. Through the meshing of the second tooth plate 27 and the first tooth ring 28, the linear motion is converted into the continuous reciprocating rotation of the rotary kiln 4.

[0060] Furthermore, the reciprocating rotation subjectes the powder inside the kiln to bidirectional centrifugal and dispersing forces. Combined with the multi-layered guide vanes spaced throughout the kiln, the powder is fully dispersed and maximized, increasing the contact area with the high-temperature kiln wall and steam. This avoids incomplete deacidification caused by powder agglomeration, achieving deep deacidification. Simultaneously, the drive motor 37 can precisely adjust the speed, ensuring the rotary kiln 4 maintains a stable process speed of 1.5-2.5 r / min. Combined with the 1.5-2° tilt angle of the rotary kiln 4, the residence time of the powder inside the kiln can be precisely controlled to 15-25 minutes, perfectly matching the deacidification temperature of 500-520℃. This enables precise temperature and time control of the deacidification reaction, ensuring the stability of the deacidification effect and providing structural support for the precise control of product pH, moisture, and free chlorine levels.

[0061] Example 3:

[0062] Reference Figure 10 and Figure 11 Compared to Embodiment 1 and Embodiment 2, in this embodiment, a first fixed column 30 is fixedly installed on the first base 1. A third gear 31 is rotatably connected to the side of the first fixed column 30 near the second gear ring 29. The third gear 31 and the two sides of the first fixed column 30 are respectively rotatably connected to the first elastic plate 32 through connecting rods. A third gear ring 33 is fixedly installed on the outer wall of the other side of the rotary kiln 4. A second fixed column 34 is fixedly installed on the first base 1. A fourth gear 35 is rotatably connected to the side of the second fixed column 34 near the third gear ring 33. The fourth gear 35 and the two sides of the second fixed column 34 are respectively rotatably connected to the second elastic plate 36 through connecting rods.

[0063] The second gear ring 29 meshes with the third gear 31, the third gear ring 33 meshes with the fourth gear 35, and the first elastic plate 32 and the second elastic plate 36 are elastic striking plate structures.

[0064] In this embodiment, the spring vibration assembly is used to intermittently vibrate the rotary kiln tube wall by the reciprocating rotation of the rotary kiln 4 itself, preventing the fumed silica powder from sticking to the wall due to its excessively fine particle size. It includes a second toothed ring 29, a first fixed column 30, a third gear 31, and a first elastic plate 32 fixedly mounted on one side of the outer wall of the rotary kiln 4; and a third toothed ring 33, a second fixed column 34, a fourth gear 35, and a second elastic plate 36 fixedly mounted on the other side of the outer wall of the rotary kiln 4. The first fixed column 30 and the second fixed column 34 are both fixedly mounted on the first base 1 and symmetrically distributed on both sides of the rotary kiln 4; the third gear 31 rotates... A first elastic plate 32 is rotatably connected to the side of the first fixed post 30 near the second gear ring 29, and the second gear ring 29 meshes with the third gear 31. The second elastic plate 32 is rotatably connected to both sides of the third gear 31 and the first fixed post 30 via a connecting rod. The fourth gear 35 is rotatably connected to the side of the second fixed post 34 near the third gear ring 33, and the third gear ring 33 meshes with the fourth gear 35. The second elastic plate 36 is rotatably connected to both sides of the fourth gear 35 and the second fixed post 34 via a connecting rod. Both the first elastic plate 32 and the second elastic plate 36 are elastic striking plate structures, possessing good elasticity and fatigue resistance.

[0065] Furthermore, the spring vibration assembly and the rotary kiln 4 are designed as a linkage self-drive system, requiring no additional drive source. Its operating principle is as follows: when the rotary kiln 4 reciprocates, it drives the second toothed ring 29 and the third toothed ring 33 on its outer wall to rotate synchronously. Through the meshing of the toothed rings and gears, the third gear 31 and the fourth gear 35 are driven to rotate respectively. When the gears rotate, the connecting rod drives the elastic striking plates on both sides to make periodic elastic swings. When the striking plates swing to contact the tube wall of the rotary kiln 4, they use the impact force generated by the elastic deformation to strike the tube wall, realizing intermittent vibration. After the strike, the plate swings again through elastic reset, repeating the cycle.

[0066] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A rotary kiln-type deacidification device for deacidification of silica, comprising a deacidification component, a rotary component, and a vibrating component, characterized in that: The deacidification component is used to desorb HCl from the powder surface and then continuously remove acid gas through airflow. At the same time, it relies on rotation to achieve uniform heating and deep deacidification. The deacidification component includes a first base (1) and a rotary kiln (4) rotatably disposed on the top of the first base (1). The rotary assembly is used to drive the rotary kiln (4) kiln body pipe to rotate continuously to maintain the full reaction of the internal material. The rotary assembly consists of a drive unit and a reciprocating unit. The drive unit is used to provide continuous intermittent reciprocating power. The drive unit includes a fixed chamber (11) fixedly installed on the top of the first base (1). The vibratory assembly is used to intermittently vibrate the rotary kiln tube wall by the reciprocating rotation of the rotary kiln (4) to prevent material from sticking to the wall. The vibratory assembly includes a second toothed ring (29) fixedly disposed on the outer wall of one side of the rotary kiln (4).

2. The rotary kiln-type deacidification equipment for deacidification of silica according to claim 1, characterized in that, A second base (2) is fixedly installed on one side of the first base (1), a third base (3) is fixedly installed on one side of the second base (2), a feed hopper (5) is fixedly installed on one side of the rotary kiln (4), a steam port (6) is fixedly installed on one side of the feed hopper (5), and a discharge hopper (7) is fixedly installed on the other side of the rotary kiln (4).

3. The rotary kiln-type deacidification equipment for deacidification of silica according to claim 2, characterized in that, The top of the second base (2) is fixedly provided with a discharge cyclone separator (8) that communicates with the discharge bin (7), and the top of the third base (3) is fixedly provided with a bag filter (9) that communicates with the discharge cyclone separator (8). A flue gas fan (10) that communicates with the bag filter (9) is fixedly provided on one side.

4. The rotary kiln-type deacidification equipment for deacidification of silica according to claim 1, characterized in that, A first fixing plate (13) is fixedly installed inside the fixing chamber (11). Several fixing blocks (15) are fixedly installed on the first fixing plate (13). A second fixing plate (14) is fixedly installed on the top of the fixing blocks (15). A worm gear (16) is rotatably connected between two of the fixing blocks (15). A worm wheel (17) is rotatably connected to the side of the first fixing plate (13) near the worm gear (16). A first bevel gear (18) is fixedly connected to one side of the worm gear (16). A second bevel gear (19) is rotatably connected to the side of the first fixing plate (13) near the first bevel gear (18). A drive motor (37) is fixedly installed inside the first base (1) below the fixing chamber (11). The drive end of the drive motor (37) is fixedly connected to the second bevel gear (19).

5. The rotary kiln-type deacidification equipment for deacidification of silica according to claim 4, characterized in that, The reciprocating unit is used to drive the rotary kiln (4) to rotate continuously. The reciprocating unit includes a first gear (20) rotatably connected to the top of the second fixed plate (14) and fixedly connected to the worm gear (17). A second gear (21) is rotatably connected to the side of the second fixed plate (14) near the first gear (20). A first sector tooth (22) is fixedly provided on the first gear (20), and a second sector tooth (23) is fixedly provided on the second gear (21).

6. The rotary kiln-type deacidification equipment for deacidification of silica according to claim 5, characterized in that, A slide groove (24) is fixedly provided on the top of the second fixed plate (14) near the two fan-shaped teeth. A slider (25) is slidably connected inside the slide groove (24). A first toothed plate (26) is fixedly connected on the side of the slider (25) near the two fan-shaped teeth. A second toothed plate (27) is fixedly provided on the top of the slider (25). A fixed cylinder (12) connected to the top of the fixed chamber (11) is fixedly provided. The rotary kiln (4) and the fixed cylinder (12) are rotatably connected. A first toothed ring (28) is fixedly provided on the outer wall of the rotary kiln (4) and inside the fixed cylinder (12).

7. The rotary kiln-type deacidification equipment for deacidification of silica according to claim 1, characterized in that, A first fixed column (30) is fixedly installed on the first base (1). A third gear (31) is rotatably connected to the side of the first fixed column (30) near the second gear ring (29). The third gear (31) and the two sides of the first fixed column (30) are respectively rotatably connected to the first elastic plate (32) through connecting rods. A third gear ring (33) is fixedly installed on the outer wall of the other side of the rotary kiln (4). A second fixed column (34) is fixedly installed on the first base (1). A fourth gear (35) is rotatably connected to the side of the second fixed column (34) near the third gear ring (33). The fourth gear (35) and the two sides of the second fixed column (34) are respectively rotatably connected to the second elastic plate (36) through connecting rods.

8. The rotary kiln-type deacidification equipment for deacidification of silica according to claim 6, characterized in that, The worm (16) meshes with the worm wheel (17), the first bevel gear (18) meshes with the second bevel gear (19), the first gear (20) meshes with the second gear (21), the first sector tooth (22) and the second sector tooth (23) face opposite directions, the two sector teeth mesh with the first tooth plate (26) intermittently by rotation, and the second tooth plate (27) meshes with the first tooth ring (28).

9. The rotary kiln-type deacidification equipment for deacidification of silica according to claim 7, characterized in that, The second toothed ring (29) meshes with the third gear (31), the third toothed ring (33) meshes with the fourth gear (35), and the first elastic plate (32) and the second elastic plate (36) are elastic striking plate structures.

10. The processing technology of the rotary kiln-type deacidification equipment for deacidification of silica as described in any one of claims 1-9, characterized in that, Includes the following steps: Step 1: Feed pretreatment. After the fumed silica powder is cooled and aggregated to 180-220℃, it is transported to the feed hopper (5) of the rotary kiln (4). At the same time, steam is introduced through the steam port (6) of the feed hopper (5). The ratio of steam to fumed silica feed is not less than 1:5, so that the powder and steam are initially mixed in the feed hopper (5). Step 2: Equipment startup and parameter debugging. Start the drive motor (37) to drive the rotary assembly to run, so that the rotary kiln (4) rotates continuously at a speed of 1.5-2.5r / min. At the same time, start the external heating equipment at the bottom of the rotary kiln (4) and adjust the heating power through the thyristor components to ensure that the temperature in the discharge bin (7) of the rotary kiln (4) is stable at 500-520℃. Check the linkage status between the spring vibration assembly and the rotary kiln (4) to ensure that the first elastic plate (32) and the second elastic plate (36) can rotate with the rotary kiln (4) to achieve intermittent vibration. Step 3: High-temperature deacidification reaction. After the mixture of fumed silica and steam enters the rotary kiln (4), the powder is fully dispersed by the reciprocating rotation of the rotary kiln (4) and the scattering effect of the multi-layer guide vanes in the kiln. At the same time, the uniform heat conduction of the external heating of the rotary kiln (4) allows the powder to stay in the kiln at a temperature of 500-520℃ for 15-25 minutes, allowing the chlorine on the surface of the powder to desorb and form hydrogen chloride, which combines with water vapor to form acid gas. The acid gas is continuously carried away from the surface of the powder by the airflow, thus completing the deep deacidification. Step 4: Material discharge and conveying. After the deacidification reaction, the fumed silica powder enters the discharge hopper (7) of the rotary kiln (4). Ambient air (100-200 Nm³ / h) is introduced through the Venturi feeder at the bottom of the discharge hopper (7) to convey the qualified powder to the subsequent packaging stage. The pH value of the powder after deacidification is controlled between 3.9 and 4.3, the moisture content is ≤0.8%, and the free chlorine content is ≤120 mg / kg. Step 5: Tail gas treatment and powder recovery. After the acidic high-temperature tail gas in the discharge hopper (7) is discharged from the top, it is cooled to 180-220℃ by the cooler and then enters the discharge cyclone separator (8) and the bag filter (9) in sequence to collect the gas phase silica powder that escapes from the tail gas. The collected powder is fed by the Venturi feeder into hot air (140℃, 80-100Nm³ / h) and transported back to the rotary kiln (4) feed hopper (5) to participate in the deacidification reaction again. The tail gas treated by the bag filter (9) is discharged by the flue gas fan (10). By adjusting the variable frequency speed of the flue gas fan (10) and the pipeline regulating valve, the pressure of the gas phase outlet pipeline of the rotary kiln feed cyclone separator is 1.0-3.0KPa higher than the pressure of the rotary kiln (4) discharge hopper (7). Step 6: Equipment anti-sticking and anti-condensation protection. During the entire deacidification process, the first elastic plate (32) and the second elastic plate (36) of the spring vibration assembly intermittently vibrate the kiln tube wall as the rotary kiln (4) rotates to prevent the gas phase silica powder from sticking to the wall. At the same time, the saturated steam coil of the cyclone separator entering and exiting the rotary kiln (4) is kept heated (steam pressure not lower than 0.4MPa (G)), the bag filter (9) and pipelines, and the armored cable electric heating of the Venturi (temperature control 200±20℃) to prevent acid gas from condensing.

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