A pulverizing and spray drying integrated device for titanium dioxide production

Abstract

The utility model discloses a kind of for titanium dioxide production's smashing and spray drying integration device, it is related to titanium dioxide production technical field, including preliminary smashing bin, the inside of the preliminary smashing bin is provided with crushing mechanism, the inside of the preliminary smashing bin is provided with hot air distributor, the bottom of the preliminary smashing bin is fixedly connected with Venturi feeder, the bottom of the Venturi feeder is fixedly connected with fine grinding collector, the crushing mechanism, hot air distributor and fine grinding collector are used to realize the full-closed continuous production from wet filter material to dry powder finished product.The utility model integrates three core processes of preliminary crushing, drying and fine grinding in a set of sealed equipment by crushing mechanism, hot air distributor and fine grinding collector, realizes the full-closed continuous production from wet filter material to dry powder finished product, greatly shortens process flow, reduces equipment floor area and investment cost.

Description

Technical Field

[0001] This utility model relates to the field of titanium dioxide production technology, and in particular to an integrated device for pulverizing and spray drying in titanium dioxide production. Background Technology

[0002] Titanium dioxide is an important inorganic chemical pigment widely used in coatings, plastics, and papermaking. Its main component is titanium dioxide, with the molecular formula TiO2. Its crystal structure is classified into three types: rutile, anatase, and plate-type. Plate-type titanium dioxide has poor stability and is not industrially viable; rutile and anatase are the main types used. During its production process, especially in the post-processing stage, the filter cake after coating and washing is highly susceptible to moisture absorption and agglomeration, forming hard lumps.

[0003] In existing titanium dioxide production, traditional processes typically treat crushing, drying, and re-crushing as separate steps, performed in equipment such as flash dryers, spray drying towers, and air jet mills. This multi-equipment, segmented processing model has significant drawbacks. First, the transfer and transport of materials between different devices increases energy consumption and time costs. Furthermore, materials exposed to air are prone to re-absorbing moisture or becoming contaminated. Additionally, the equipment requires a large footprint, resulting in high investment and maintenance costs. Consequently, the process flow is lengthy, with numerous control points, which is detrimental to product quality stability.

[0004] To address the issue of independent processes in titanium dioxide production, a fully enclosed, continuous production process from wet filter material to finished dry powder has been achieved by integrating the three core processes of preliminary crushing, drying, and fine grinding into a single sealed unit. This significantly shortens the process flow and reduces equipment footprint and investment costs. Optimized process integration eliminates material transfer and storage waiting steps between traditional independent units, allowing wet filter material to directly enter the equipment for continuous crushing, drying, and grinding operations. This shortens batch processing time, increases unit time capacity, and reduces material loss due to multiple loading and unloading operations. Furthermore, the entire process operates in a controlled environment, avoiding quality fluctuations caused by variations in environmental temperature and humidity and human error in traditional segmented production. This ensures consistency in key indicators such as titanium dioxide particle size distribution, whiteness, and hiding power, improving batch-to-batch stability.

[0005] However, existing titanium dioxide production processes still suffer from problems such as easy adhesion to the walls and easy agglomeration. Material adhering to the walls may experience localized overheating or reaction due to prolonged retention, leading to abnormal particle size or impurities in some titanium dioxide particles, affecting key performance indicators such as whiteness and hiding power of the final product. Moreover, agglomerated titanium dioxide is difficult to disperse evenly in subsequent processing, resulting in a grainy texture, uneven gloss, or decreased mechanical properties on the product surface, affecting the end-user experience. Utility Model Content

[0006] The purpose of this invention is to address the shortcomings of existing technologies by proposing an integrated crushing and spray drying device for titanium dioxide production, which solves the problem of independent processes in titanium dioxide production.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] An integrated crushing and spray drying device for titanium dioxide production includes a primary crushing chamber with a crushing mechanism and a hot air distributor inside. A Venturi feeder is fixedly connected to the bottom of the primary crushing chamber, and a fine grinding collector is fixedly connected to the bottom of the Venturi feeder. The crushing mechanism, hot air distributor, and fine grinding collector enable fully enclosed continuous production from wet filter material to dry powder product. From the crushing mechanism in the primary crushing chamber to the distributed conveying by the Venturi feeder, and then to the drying and grinding in the fine grinding collector, each step is directly connected via pipelines and mechanical structures, forming a closed-loop production chain, eliminating intermediate transfer links, and reducing material loss and time waste.

[0009] As a further improvement of this utility model, a star-shaped feeder is fixedly connected to the top of the primary crushing chamber, and a feed inlet is fixedly connected to the top of the star-shaped feeder. The crushing mechanism is fixedly connected to the inner top of the primary crushing chamber, and the inner wall of the primary crushing chamber is designed with a mirror polishing finish. The mirror polishing treatment can reduce the adsorption of moisture and sticky components in the wet filter material on the wall surface, avoiding clumping, blockage, or cross-contamination caused by wall adhesion.

[0010] As a further improvement of this utility model, a Venturi feeder is fixedly connected to the bottom end of the preliminary crushing chamber. A high-temperature hot air pipe is fixedly connected through the center of the bottom end of the Venturi feeder. A hot air distributor is fixedly connected to the outer surface of the high-temperature hot air pipe, with the end of the hot air distributor away from the high-temperature hot air pipe located outside the preliminary crushing chamber. The high-temperature hot air pipe enters directly from the center of the bottom end of the Venturi feeder, forming a high-speed jet. Utilizing the Venturi effect, a negative pressure is generated at the throat, rapidly drawing in the pre-crushed wet material and dispersing it into a fine particle stream. This avoids material accumulation or agglomeration within the pipe, ensuring that the particles are uniformly suspended in the airflow.

[0011] As a further improvement of this utility model, a centrifugal atomizer is inserted through the top of the preliminary crushing chamber. The centrifugal atomizer is used to atomize the titanium dioxide slurry to be dried and spray it into the tower. The top outer wall of the high-temperature hot air pipe is fixedly connected to the spray drying tower. The inner wall of the preliminary crushing chamber is provided with a heat insulation jacket to prevent wet materials from adhering to the inner wall of the preliminary crushing chamber. The top of the high-temperature hot air pipe is directly connected to the spray drying tower, forming a temperature gradient from bottom to top. The hot air comes into countercurrent contact with the atomized droplets in the tower. The high-temperature zone at the bottom quickly evaporates the surface moisture of the droplets, the medium-temperature zone in the middle prevents particles from sticking together, and the low-temperature zone at the top completes the final drying, thereby ensuring the uniformity of product moisture content.

[0012] As a further improvement of this utility model, a finished product collection chamber is fixedly connected to the bottom of the fine grinding collector, and several high-pressure steam nozzles are fixedly connected to the top of the finished product collection chamber. These high-pressure steam nozzles are used to inject high-speed steam into the cooling jacket to form a strong rotating airflow. A cooling jacket is installed inside the finished product collection chamber. The high-pressure steam nozzles inject high-speed steam into the cooling jacket, utilizing the dual effects of the sensible and latent heat of the steam to quickly absorb the heat from the finished titanium dioxide. Compared to traditional natural cooling or static air cooling, the cooling time is shortened, making it suitable for emergency cooling of materials after high-temperature grinding and preventing particle agglomeration caused by heat accumulation.

[0013] As a further improvement of this utility model, a cyclone separator is provided at the bottom of the finished product collection bin, a bag filter is provided at the end of the cyclone separator away from the finished product collection bin, and an induced draft fan is provided at the end of the bag filter away from the cyclone separator. The cyclone separator initially captures large dust particles, and then the bag filter further filters out fine powder particles. This dual purification ensures that the concentration of particulate matter in the exhaust gas is far below the environmental emission standards, meeting the requirements of clean production and sustainable development.

[0014] Compared with the prior art, the advantages of this utility model are as follows:

[0015] 1. By integrating the three core processes of preliminary crushing, drying, and fine grinding into a single sealed device through a crushing mechanism, hot air distributor, and fine grinding collector, this system achieves fully enclosed continuous production from wet filter material to dry powder product. This significantly shortens the process flow and reduces equipment footprint and investment costs. The continuous design of the internal material flow path eliminates the breakpoints in material transfer and storage inherent in traditional segmented production. Wet filter material directly enters the equipment to complete the continuous crushing-drying-grinding operation, reducing material loss and time waste in intermediate stages and improving overall process smoothness.

[0016] 2. The mirror-polished inner wall design of the Venturi feeder, insulation jacket, and primary grinding chamber effectively solves the problems of titanium dioxide sticking to the walls and clumping during production, ensuring production stability and continuity. The high-speed airflow of the Venturi feeder and the mirror-polished inner wall form a physical anti-sticking layer, reducing material adhesion points, while the insulation jacket maintains a uniform temperature on the chamber wall, preventing localized condensation that could lead to the solidification and clumping of wet materials. This combined approach minimizes the risk of wall sticking. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model.

[0018] In the diagram: 1. Star feeder; 2. Feed inlet; 3. Crushing mechanism; 4. Primary crushing bin; 5. Venturi feeder; 6. High-temperature hot air duct; 7. Centrifugal atomizer; 8. Hot air distributor; 9. Spray drying tower; 10. Insulation jacket; 11. Fine grinding collector; 12. High-pressure steam nozzle; 13. Cooling jacket; 14. Finished product collection bin; 15. Exhaust fan; 16. Bag filter; 17. Cyclone separator. Detailed Implementation

[0019] To make the above-mentioned objectives, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0020] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0021] See attached document Figure 1 An integrated crushing and spray drying device for titanium dioxide production includes a crushing mechanism 3, a primary crushing chamber 4, a Venturi feeder 5, a high-temperature hot air duct 6, a centrifugal atomizer 7, a hot air distributor 8, a spray drying tower 9, an insulation jacket 10, a fine grinding collector 11, a high-pressure steam nozzle 12, a cooling jacket 13, a finished product collection chamber 14, an induced draft fan 15, a bag filter 16, and a cyclone separator 17.

[0022] In this embodiment, titanium dioxide production is used as an example. When using this invention, the agglomerated titanium dioxide filter cake is first fed evenly and sealed into the primary crushing chamber 4 through the feed inlet 2 and the star-shaped feeder 1. The crushing mechanism 3 inside the primary crushing chamber 4 operates, with a pair of toothed crushing rollers driven by the crushing mechanism 3 rotating in opposite directions, squeezing and shearing the large filter cake into fine particles. The sealed and continuous feeding of the star-shaped feeder 1 and the stable operation of the crushing mechanism 3 form a continuous operation chain from feeding to crushing, reducing production interruptions caused by manual intervention or equipment start-up and shutdown. The uniform crushing effect provides raw materials with consistent particle size for subsequent drying and grinding processes, avoiding process fluctuations caused by differences in raw material particle size, and improving the stability and predictability of the overall production rhythm.

[0023] The initially crushed material falls to the Venturi feeder 5, where high-speed hot air supplied by the high-temperature hot air pipe 6 instantly disperses it and blows it into the top of the spray drying tower 9. Simultaneously, hot air from the hot air furnace enters the tower through the hot air distributor 8 in an optimal flow pattern. Based on the upstream process, when atomization of the titanium dioxide slurry is required, the dried titanium dioxide slurry can be atomized by the centrifugal atomizer 7 and sprayed into the spray drying tower 9. Inside the spray drying tower 9, the material comes into full contact with the high-temperature hot air, and the moisture is rapidly evaporated. The tower wall is continuously heated by the insulation jacket 10, which is powered by electricity or circulated with heat transfer oil, effectively preventing wet material from adhering to the tower wall. The Venturi feeder 5, combined with high-speed hot air, instantly disperses the initially crushed material into a fine particle stream, avoiding localized accumulation or uneven drying caused by large pieces of material directly entering the spray drying tower 9. This dispersion method improves the contact efficiency between the material and the hot air, accelerates moisture evaporation, and reduces the risk of wall adhesion caused by material agglomeration.

[0024] After initial drying, the material falls to the bottom of the spray drying tower 9 and enters the fine grinding collector 11. Multiple high-pressure steam nozzles 12, tangentially arranged at the top of the finished product collection chamber 14, inject high-speed steam into the chamber, creating a strong rotating airflow. The falling material particles collide and rub against each other in the high-speed vortex, achieving fine grinding, while simultaneously undergoing efficient heat exchange with the high-temperature steam, completing the final drying process. The resulting high-quality titanium dioxide product falls into the finished product collection chamber 14 with a cooling jacket 13 for cooling before being discharged. The high-speed rotating airflow formed by the high-pressure steam nozzles 12 simultaneously completes the fine grinding and heat exchange drying of the material: the particles collide and rub against each other in the vortex, achieving self-grinding and reducing the energy consumption and wear of traditional mechanical grinding; the high-temperature steam directly participates in heat exchange, simultaneously evaporating moisture during the grinding process, avoiding the need for secondary drying, shortening the process flow, and thus improving energy efficiency.

[0025] After the high-quality titanium dioxide finished product is discharged from the finished product collection bin 14, the exhaust gas containing a small amount of fine powder sequentially enters the cyclone separator 17 and the bag filter 16 for purification treatment. The exhaust gas that meets environmental protection standards is drawn out by the induced draft fan 15. The cyclone separator 17 initially captures large dust particles, and then the bag filter 16 further filters out the fine powder. The dual purification ensures that the concentration of particulate matter in the exhaust gas is far below the environmental emission standards, meeting the requirements of clean production and sustainable development.

[0026] 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. An integrated pulverizing and spray drying device for titanium dioxide production, comprising a primary pulverizing chamber (4), characterized in that, The primary crushing chamber (4) is equipped with a crushing mechanism (3) and a hot air distributor (8). A venturi feeder (5) is fixedly connected to the bottom of the primary crushing chamber (4). A fine grinding collector (11) is fixedly connected to the bottom of the venturi feeder (5). The crushing mechanism (3), the hot air distributor (8), and the fine grinding collector (11) are used to realize a fully enclosed continuous production from wet filter material to dry powder finished product.

2. The integrated pulverizing and spray drying device for titanium dioxide production according to claim 1, characterized in that, The top of the primary crushing chamber (4) is fixedly connected to a star feeder (1), the top of the star feeder (1) is fixedly connected to a feed inlet (2), the crushing mechanism (3) is fixedly connected to the top of the interior of the primary crushing chamber (4), and the inner wall of the primary crushing chamber (4) is designed with mirror polishing.

3. The integrated pulverizing and spray drying device for titanium dioxide production according to claim 2, characterized in that, A high-temperature hot air pipe (6) is fixedly connected through the center of the bottom end of the Venturi feeder (5). The hot air distributor (8) is fixedly connected to the outer surface of the high-temperature hot air pipe (6). The end of the hot air distributor (8) away from the high-temperature hot air pipe (6) is set outside the primary crushing chamber (4).

4. The integrated pulverizing and spray drying device for titanium dioxide production according to claim 3, characterized in that, A centrifugal atomizer (7) is inserted through the top of the primary crushing chamber (4). The centrifugal atomizer (7) is used to atomize the titanium dioxide slurry that needs to be dried and spray it into the tower. A spray drying tower (9) is fixedly connected to the outer wall of the top of the high-temperature hot air pipe (6). A heat insulation jacket (10) is provided on the inner wall of the primary crushing chamber (4). The heat insulation jacket (10) is used to prevent wet materials from adhering to the inner wall of the primary crushing chamber (4).

5. The integrated pulverizing and spray drying device for titanium dioxide production according to claim 1, characterized in that, The bottom end of the fine grinding collector (11) is fixedly connected to the finished product collection chamber (14), and the top end of the finished product collection chamber (14) is fixedly connected to several high-pressure steam nozzles (12). The high-pressure steam nozzles (12) are used to spray high-speed steam into the finished product collection chamber (14) to form a strong rotating airflow. The interior of the finished product collection chamber (14) is provided with a cooling jacket (13).

6. The integrated pulverizing and spray drying device for titanium dioxide production according to claim 5, characterized in that, A cyclone separator (17) is provided at the bottom of the finished product collection bin (14). A bag filter (16) is provided at the end of the cyclone separator (17) away from the finished product collection bin (14). An induced draft fan (15) is provided at the end of the bag filter (16) away from the cyclone separator (17).

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