Titanium dioxide grading system and method
By using a multi-stage grading system and sand milling, the problem of insufficient grading accuracy in large-diameter hydrocyclones was solved, resulting in improved uniformity of titanium dioxide particle size distribution and increased permeability, thus enhancing product quality.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-23
- Publication Date
- 2026-03-13
AI Technical Summary
Large-diameter hydrocyclones suffer from low separation factor and weak centrifugal force, resulting in a significant decrease in the classification accuracy of micron-sized particles. This makes it difficult to effectively remove large particles, affecting the gloss and processing performance of titanium dioxide.
A multi-stage grading system is adopted, which combines a feed hopper, hydrocyclone, dilution hopper and sand mill. It utilizes the inter-particle interaction and swirling field characteristics at high concentration to separate particles in titanium dioxide slurry, and achieves high-precision grading through multiple dilution and sand milling processes.
It improves the grading accuracy of titanium dioxide, significantly improves the uniformity of particle size distribution, and has excellent permeability and dispersibility, thereby enhancing the quality and performance of titanium dioxide products.
Smart Images
Figure CN121649035A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of titanium dioxide processing technology, and in particular to a titanium dioxide grading system and method. Background Technology
[0002] Titanium dioxide (TiO2), as the highest-performance white pigment, is widely used in coatings, plastics, papermaking, inks, and other fields. Its optical properties (such as hiding power and whiteness) and application properties (such as dispersibility and durability) are highly dependent on the uniformity of its particle size distribution. High-quality titanium dioxide requires a narrow particle size distribution and strict control of the content of large particles larger than 1 μm to avoid affecting the product's gloss and processing performance. In the post-processing of titanium dioxide, efficient and precise removal of large particles is a core element in improving product quality, especially in large-scale production where both processing efficiency and grading accuracy must be considered.
[0003] Currently, hydrocyclones have become the mainstream equipment for titanium dioxide particle classification due to their simple structure and continuous operation. Their working principle is as follows: material enters the hydrocyclone at high tangential speed, forming outer and inner swirling currents under centrifugal force. Coarse particles, due to greater centrifugal force, move towards the hydrocyclone wall and are discharged from the bottom outlet; fine particles are separated from the overflow outlet by the inner swirling current, thus achieving classification. Currently, large-diameter hydrocyclones are mostly used to increase throughput and meet the needs of large-scale production.
[0004] However, large-diameter hydrocyclones suffer from drawbacks such as low separation factor and weak centrifugal force, resulting in a significant decrease in their classification accuracy for micron-sized particles (especially critical particles with a diameter close to 1 μm), making it difficult to effectively remove large particles. Furthermore, the uneven flow field distribution inside large-diameter hydrocyclones easily leads to particle back-mixing, further reducing the classification efficiency of titanium dioxide particles. Summary of the Invention
[0005] This application provides a titanium dioxide grading system and method to solve the technical problem that existing large-diameter hydrocyclones have defects such as low separation factor and weak centrifugal force, which leads to a significant decrease in the grading accuracy of micron-sized particles and makes it difficult to effectively remove large particles.
[0006] The first aspect of this application provides a titanium dioxide grading system, comprising: The feed hopper is provided with a feed inlet and a discharge outlet; the feed inlet is connected to a plurality of hydrocyclones; the hydrocyclones are located outside the feed hopper; the hydrocyclones are provided with an overflow outlet and a bottom flow outlet; the overflow outlet is connected to the discharge outlet, and the bottom flow outlet extends into the bottom flow collection hopper; And, a control module, the control module being configured to: Adjust the concentration of the first titanium dioxide slurry to be graded to the first preset concentration range; The first titanium dioxide slurry is fed into the feed hopper through the feed inlet; the first titanium dioxide slurry enters the hydrocyclone through the feed hopper; The hydrocyclone is activated to separate particles in the first titanium dioxide slurry using the interparticle interaction and swirling field characteristics at high concentrations. The resulting first overflow flows from the overflow port to the discharge port of the feed hopper, and the resulting first underflow flows from the underflow port to the underflow collection hopper. The first overflow includes: a first titanium dioxide intermediate product containing particles of a first particle size range and a second particle size range; the second particle size range is smaller than the first particle size range. The first underflow includes: a second titanium dioxide slurry containing particles of the first particle size range. The concentration of the first titanium dioxide intermediate product is diluted to a second preset concentration range; the second preset concentration range is smaller than the first preset concentration range. The diluted first titanium dioxide intermediate product is fed into the feed hopper through the feed inlet; The hydrocyclone is activated to separate the particles in the first titanium dioxide intermediate product, causing the generated second overflow to flow from the overflow port to the discharge port of the feed hopper, and the generated second underflow to flow from the underflow port to the underflow collection hopper; the second overflow includes: titanium dioxide target product containing particles in the second particle size range; the second underflow includes: third titanium dioxide slurry containing particles in the first particle size range.
[0007] In some embodiments, the feed inlet is connected to the hydrocyclone via a first material transfer pipe; The feeding hopper is provided with a second material transfer pipe, which is arranged along the height direction of the feeding hopper. One end of the second material transfer pipe is connected to the overflow port through an overflow pipe; the other end of the second material transfer pipe is connected to the discharge port. The underflow outlet is connected to the underflow pipe, and the end of the underflow pipe away from the underflow outlet extends into the underflow collection chamber.
[0008] In some embodiments, the system further includes: a dilution chamber; The control module is further configured as follows: The concentration of the first titanium dioxide slurry to be graded is adjusted to a first preset concentration range using the dilution chamber. In addition, the concentration of the first titanium dioxide intermediate product is diluted to a second preset concentration range using the dilution chamber.
[0009] In some embodiments, the system further includes: a sand mill; The control module is also configured to: Based on the first titanium dioxide slurry, the first titanium dioxide slurry is pre-dispersed using the sand mill, and then fed into the feed hopper. The feed pump speed of the sand mill is adjusted to 450 rpm. Based on the first titanium dioxide intermediate product, the sand mill is used to perform light grinding and depolymerization treatment. After the light grinding and depolymerization treatment, the first titanium dioxide intermediate product is fed into the dilution chamber.
[0010] In some embodiments, the control module is further configured to: Based on the second titanium dioxide slurry, the sand mill is used again for pre-dispersion treatment. After the pre-dispersion treatment, the second titanium dioxide slurry is fed into the feed hopper. And, obtain a second titanium dioxide intermediate product located in the first particle size range from the target titanium dioxide product; Based on the second titanium dioxide intermediate product and the third titanium dioxide slurry, the second titanium dioxide intermediate product and the third titanium dioxide slurry are subjected to a light grinding and depolymerization treatment using the sand mill. After the light grinding and depolymerization treatment, they are fed into the dilution chamber.
[0011] In some embodiments, the underflow collection chamber includes: The collection bin body has a baffle plate at the top and an outlet at the bottom.
[0012] The second aspect of this application provides a titanium dioxide grading method, applied to a titanium dioxide grading system as described in any one of the first aspects above, comprising: Adjust the concentration of the first titanium dioxide slurry to be graded to the first preset concentration range; The first titanium dioxide slurry is fed into the feed hopper through the feed inlet; the first titanium dioxide slurry enters the hydrocyclone through the feed hopper; The hydrocyclone is activated to separate particles in the first titanium dioxide slurry using the interparticle interaction and swirling field characteristics at high concentrations. The resulting first overflow flows from the overflow port to the discharge port of the feed hopper, and the resulting first underflow flows from the underflow port to the underflow collection hopper. The first overflow includes: a first titanium dioxide intermediate product containing particles of a first particle size range and a second particle size range; the second particle size range is smaller than the first particle size range. The first underflow includes: a second titanium dioxide slurry containing particles of the first particle size range. The concentration of the first titanium dioxide intermediate product is diluted to a second preset concentration range; the second preset concentration range is smaller than the first preset concentration range. The diluted first titanium dioxide intermediate product is fed into the feed hopper through the feed inlet; The hydrocyclone is activated to separate the particles in the first titanium dioxide intermediate product, causing the generated second overflow to flow from the overflow port to the discharge port of the feed hopper, and the generated second underflow to flow from the underflow port to the underflow collection hopper; the second overflow includes: titanium dioxide target product containing particles in the second particle size range; the second underflow includes: third titanium dioxide slurry containing particles in the first particle size range.
[0013] In some embodiments, after the step of adjusting the concentration of the first titanium dioxide slurry to be graded to a first preset concentration range, the method includes: Based on the first titanium dioxide slurry, a sand mill is used for pre-dispersion treatment.
[0014] In some embodiments, prior to the step of diluting the concentration of the first titanium dioxide intermediate product to a second preset concentration range, the method includes: The feed pump speed of the sand mill is adjusted to 450 rpm, and the first titanium dioxide intermediate product is subjected to light grinding and deagglomeration treatment using the sand mill.
[0015] In some embodiments, the method further includes: Based on the second titanium dioxide slurry, the step of pre-dispersion treatment using a sand mill is repeated; And, obtain a second titanium dioxide intermediate product located in the first particle size range from the target titanium dioxide product; Based on the second titanium dioxide intermediate product and the third titanium dioxide slurry, the step of light grinding and deagglomeration treatment using the sand mill is repeated.
[0016] This application provides a titanium dioxide grading system and method. The system includes: a feeding silo with an inlet and an outlet; the inlet is connected to a plurality of hydrocyclones; the hydrocyclones are located outside the feeding silo; each hydrocyclone has an overflow outlet and an underflow outlet; the overflow outlet is connected to the outlet, and the underflow outlet extends into an underflow collection silo; and a control module configured to: adjust the concentration of a first titanium dioxide slurry to be graded to a first preset concentration range; feed the first titanium dioxide slurry into the feeding silo through the inlet; allow the first titanium dioxide slurry to enter the hydrocyclones through the feeding silo; activate the hydrocyclones to separate particles in the first titanium dioxide slurry using the interparticle interaction and swirling field characteristics at high concentrations, causing a first overflow to flow from the overflow outlet to the outlet of the feeding silo, and a first underflow to flow from the underflow outlet to the underflow collection silo; the first overflow includes: a first... A first titanium dioxide intermediate product containing particles in a first particle size range and a second particle size range; the second particle size range is smaller than the first particle size range; the first underflow includes: a second titanium dioxide slurry containing particles in the first particle size range; the concentration of the first titanium dioxide intermediate product is diluted to a second preset concentration range; the second preset concentration range is smaller than the first preset concentration range; the diluted first titanium dioxide intermediate product is fed into the feed hopper through the feed inlet; the hydrocyclone is activated to separate particles in the first titanium dioxide intermediate product, so that the generated second overflow flows from the overflow port to the discharge port of the feed hopper, and the generated second underflow flows from the underflow port to the underflow collection hopper; the second overflow includes: a titanium dioxide target product containing particles in the second particle size range; the second underflow includes: a third titanium dioxide slurry containing particles in the first particle size range, so as to improve the classification accuracy of micron-sized particles through the titanium dioxide classification system and the corresponding process flow, thereby effectively removing large particles in the titanium dioxide slurry. Attached Figure Description
[0017] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0018] Figure 1 This is a schematic diagram of the titanium dioxide grading system in this application from one angle. Figure 2 This is a schematic diagram of the titanium dioxide grading system in this application from another perspective; Figure 3 This is a process flow diagram of the titanium dioxide grading system in this application; Figure 4 This is a flowchart illustrating the operation of the control module in this application.
[0019] Explanation of reference numerals in the attached figures: 1-Feed hopper; 11-Feed inlet; 111-First material transfer pipe; 112-Second material transfer pipe; 12-Discharge outlet; 2-Hydrocyclone; 21-Overflow outlet; 211-Overflow pipe; 22-Underflow outlet; 221-Underflow pipe; 3-Underflow collection hopper; 31-Collection hopper body; 311-Baffle; 312-Discharge outlet; 4-Control module; 5-Dilution hopper; 6-Sand mill. Detailed Implementation
[0020] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this application.
[0021] Because large-diameter hydrocyclones suffer from low separation factors and weak centrifugal forces in some technologies, their classification accuracy for micron-sized particles is significantly reduced, making it difficult to effectively remove large particles. This application provides a titanium dioxide classification system and method, which are described below: like Figure 1 The diagram shown is a schematic representation of the titanium dioxide grading system in this application.
[0022] The first aspect of this application provides a titanium dioxide grading system, comprising: The feed hopper 1 is provided with an inlet 11 and an outlet 12. The inlet 11 is connected to several hydrocyclones 2. The hydrocyclones 2 are located outside the feed hopper 1. Each hydrocyclone 2 is provided with an overflow outlet 21 and an underflow outlet 22. The overflow outlet 21 is connected to the outlet 12, and the underflow outlet 22 extends into the underflow collection hopper 3. The structure of the hydrocyclones 2 is not limited, as long as it can achieve efficient separation of coarse and fine particles in the titanium dioxide slurry.
[0023] The system also includes: a dilution chamber 5 and a sand mill 6.
[0024] The feed inlet 11 is connected to the hydrocyclone 2 via a first material transfer pipe 111; a second material transfer pipe 112 is provided inside the feed hopper 1, the second material transfer pipe 112 is arranged along the height direction of the feed hopper 1, one end of the second material transfer pipe 112 is connected to the overflow outlet 21 via an overflow pipe 211; the other end of the second material transfer pipe 112 is connected to the discharge outlet 12; the underflow outlet 22 is connected to the underflow pipe 221, and the end of the underflow pipe 221 away from the underflow outlet 22 extends into the underflow collection hopper 3, such as... Figure 2 As shown.
[0025] Specifically, the hydrocyclone 2 is a modular integrated device designed specifically for the precision classification of titanium dioxide. The core structure of the titanium dioxide classification system is as follows: an outer ring stable flow feeding chamber (feed bin 1) and a central confluence chamber (second material transfer pipe 112) are formed inside a cylindrical shell; six small-diameter hydrocyclones 2 are evenly connected in parallel along the circumference outside. Each hydrocyclone 2 uses a strong centrifugal force field to achieve efficient separation of coarse and fine particles in the titanium dioxide slurry; the feed inlets 11 are all connected to the hydrocyclones 2 to achieve uniform distribution of pressure and materials. After classification, the fine particle product (overflow) flows into the central chamber and is discharged uniformly, while the coarse particle product (underflow) enters the underflow collection bin 3 for centralized recovery, ensuring classification efficiency and clear product separation.
[0026] like Figure 4 The diagram shown is a flowchart of the operation of control module 4 in this application.
[0027] And, control module 4, which is configured to: The concentration of the first titanium dioxide slurry to be graded is adjusted to a first preset concentration range using the dilution chamber 5.
[0028] Based on the first titanium dioxide slurry, the first titanium dioxide slurry is pre-dispersed using the sand mill 6, and then fed into the feed hopper 1 after the pre-dispersed treatment.
[0029] The first titanium dioxide slurry is fed into the feed hopper 1 through the feed inlet 11; the first titanium dioxide slurry enters the hydrocyclone 2 through the feed hopper 1.
[0030] Based on the second titanium dioxide slurry, the sand mill 6 is used again for pre-dispersion treatment. After the pre-dispersion treatment, the second titanium dioxide slurry is fed into the feed hopper 1.
[0031] The hydrocyclone 2 is turned on, and the particles in the first titanium dioxide slurry are separated by the interparticle interaction and swirling field characteristics under high concentration. The resulting first overflow flows from the overflow port 21 to the discharge port 12 of the feed hopper 1, and the resulting first underflow flows from the underflow port 22 to the underflow collection hopper 3. The first overflow includes: a first titanium dioxide intermediate product containing particles of a first particle size range and a second particle size range; the second particle size range is smaller than the first particle size range; the first underflow includes: a second titanium dioxide slurry containing particles of the first particle size range.
[0032] The feed pump speed of the sand mill 6 is adjusted to 450 rpm. Based on the first titanium dioxide intermediate product, the sand mill 6 is used to perform light grinding and depolymerization treatment. After the light grinding and depolymerization treatment, the first titanium dioxide intermediate product is fed into the dilution chamber 5.
[0033] The concentration of the first titanium dioxide intermediate product is diluted to a second preset concentration range using the dilution chamber 5; the second preset concentration range is smaller than the first preset concentration range.
[0034] The diluted first titanium dioxide intermediate product is fed into the feed hopper 1 through the feed inlet 11.
[0035] The hydrocyclone 2 is turned on to separate the particles in the first titanium dioxide intermediate product, so that the generated second overflow flows from the overflow port to the discharge port 12 of the feed hopper 1, and the generated second underflow flows from the underflow port to the underflow collection hopper 3; the second overflow includes: titanium dioxide target product containing particles in the second particle size range; the second underflow includes: third titanium dioxide slurry containing particles in the first particle size range.
[0036] Obtain the second titanium dioxide intermediate product located in the first particle size range from the target titanium dioxide product.
[0037] Based on the second titanium dioxide intermediate product and the third titanium dioxide slurry, the second titanium dioxide intermediate product and the third titanium dioxide slurry are subjected to a light grinding and depolymerization treatment using the sand mill 6. After the light grinding and depolymerization treatment, they are fed into the dilution chamber 5.
[0038] This application provides a titanium dioxide grading system, in which titanium dioxide slurry is dispersed by sand milling and then enters the hydrocyclone 2 from the feed inlet 11, overflows into the central silo (second material transfer pipe (112)), and then enters the secondary sand milling and dilution, and then enters the secondary separation, overflows into the central silo, and the central silo outlet (discharge port 12) is the refined titanium dioxide product.
[0039] In this embodiment, the underflow collection chamber 3 includes: The collection silo body 31 has a baffle 311 at its top and an outlet 312 at its bottom. The baffle 311 prevents the titanium dioxide slurry ejected from the outlet 12 from overflowing outside the collection silo body 31. The outlet 312 can be connected to other equipment, such as a silo for recycling titanium dioxide target products, via a titanium dioxide slurry conveying pipeline.
[0040] like Figure 3 The diagram shown is a process flow chart of the titanium dioxide grading system in this application.
[0041] This application provides a titanium dioxide grading system, the specific process flow of which is as follows: The concentration of the raw titanium dioxide slurry to be graded (first titanium dioxide slurry) is precisely adjusted to a high concentration range of 760±20 g / L, and then fed into a sand mill 6 for pre-dispersion treatment. The high-concentration first titanium dioxide slurry is pre-dispersed by the sand mill 6, so that the particles in the first titanium dioxide slurry are separated from each other to prevent them from sticking together, and the larger particles of the first titanium dioxide slurry are ground up.
[0042] The high-concentration slurry (first titanium dioxide slurry) is pumped into the first-stage titanium dioxide classification system. Utilizing the interparticle interaction and swirling flow characteristics at high concentration, the system maximizes the separation and collection of coarse particles in the underflow. The overflow from the first classification (first overflow) is an intermediate product containing the target fine particles (first titanium dioxide intermediate product). Hydrocyclone 2, through its tangential inlet, creates a high-speed rotating flow field in the first titanium dioxide slurry. Particles are separated through a dynamic balance between centrifugal force and centripetal pull: coarse particles, due to their high density and strong centrifugal force, are thrown against the vessel wall and move downwards with the outer swirling flow, eventually being discharged from the underflow outlet 22 (underflow); fine particles, with less centrifugal force, are pulled towards the central low-pressure zone and move upwards with the inner swirling flow, being discharged from the top overflow outlet 11 (first overflow). Specifically, the high concentration of the first titanium dioxide slurry increases the particle collision frequency, and coarse particles, due to their greater inertia, are more likely to maintain their trajectory through collisions, preventing them from being carried to the first overflow by fine particles.
[0043] The underflow (second titanium dioxide slurry) generated from the first classification is returned to the upstream sand milling process for reprocessing; by performing secondary processing on the second titanium dioxide slurry, the utilization of titanium dioxide slurry is maximized and the waste of raw materials is avoided.
[0044] The overflow generated from the first classification (first overflow) is sent to the secondary sand mill 6 for light grinding and deagglomeration treatment. The feed pump speed of the sand mill 6 is adjusted to 450 rpm to increase the slurry processing throughput. Then, the slurry concentration is adjusted to a lower range of 300 ± 20 g / L. By diluting, the interaction between particles of the first titanium dioxide intermediate product is reduced, its flowability and separation selectivity are improved, and the best separation effect is achieved. The diluted first titanium dioxide intermediate product is pumped into the second-stage titanium dioxide classification system for high-precision separation. Finally, the target titanium dioxide product with the target particle size distribution is collected from the discharge port 12.
[0045] The second overflow (containing ultrafine particles) or the second underflow that does not meet the particle size requirements (second particle size range) generated by the secondary classification is returned to the secondary sand milling and dilution process for reprocessing, forming a closed-loop circulation of fine particles within the system. This ensures the particle size control accuracy of the target titanium dioxide product and achieves efficient utilization of materials.
[0046] This application provides a titanium dioxide grading system, which has the following advantages: The system effectively controls the particle size and distribution precision of titanium dioxide. The graded titanium dioxide target product exhibits particle sizes concentrated within the range of 0.2-0.3 μm, with significantly improved distribution uniformity. Performance testing shows that 600 g of the target titanium dioxide product can completely pass through a 325-mesh filter, demonstrating excellent permeability and dispersibility. This system significantly increases the permeability of titanium dioxide slurry and results in a more concentrated particle size distribution, which is beneficial for the uniformity and stability of subsequent coating processes, thus significantly improving the quality and performance of the titanium dioxide product.
[0047] A second aspect of this application provides a titanium dioxide grading method, applied to a titanium dioxide grading system described in any of the above embodiments, comprising: Adjust the concentration of the first titanium dioxide slurry to be graded to the first preset concentration range; Based on the first titanium dioxide slurry, a sand mill was used for pre-dispersion treatment; The first titanium dioxide slurry is fed into the feed hopper through the feed inlet; the first titanium dioxide slurry enters the hydrocyclone through the feed hopper; The hydrocyclone is activated to separate particles in the first titanium dioxide slurry using the interparticle interaction and swirling field characteristics at high concentrations. The resulting first overflow flows from the overflow port to the discharge port of the feed hopper, and the resulting first underflow flows from the underflow port to the underflow collection hopper. The first overflow includes: a first titanium dioxide intermediate product containing particles of a first particle size range and a second particle size range; the second particle size range is smaller than the first particle size range. The first underflow includes: a second titanium dioxide slurry containing particles of the first particle size range. Based on the second titanium dioxide slurry, the step of pre-dispersion treatment using a sand mill is repeated; The feed pump speed of the sand mill is adjusted to 450 rpm, and the first titanium dioxide intermediate product is lightly ground and deagglomerated using the sand mill. The concentration of the first titanium dioxide intermediate product is diluted to a second preset concentration range; the second preset concentration range is smaller than the first preset concentration range. The diluted first titanium dioxide intermediate product is fed into the feed hopper through the feed inlet; The hydrocyclone is activated to separate the particles in the first titanium dioxide intermediate product, causing the generated second overflow to flow from the overflow port to the discharge port of the feed hopper, and the generated second underflow to flow from the underflow port to the underflow collection hopper; the second overflow includes: titanium dioxide target product containing particles in the second particle size range; the second underflow includes: third titanium dioxide slurry containing particles in the first particle size range; Obtain the second intermediate titanium dioxide product located within the first particle size range from the target titanium dioxide product; Based on the second titanium dioxide intermediate product and the third titanium dioxide slurry, the step of light grinding and deagglomeration treatment using the sand mill is repeated.
[0048] It is worth noting that the effects of the above method embodiments can be found in the effects of the above system embodiments, and will not be repeated here.
[0049] The above detailed embodiments further illustrate the purpose, technical solution, and beneficial effects of the embodiments of this application. It should be understood that the above are merely specific embodiments of the embodiments of this application and are not intended to limit the protection scope of the embodiments of this application. Any modifications, equivalent substitutions, improvements, etc., made on the basis of the technical solutions of the embodiments of this application should be included within the protection scope of the embodiments of this application.
Claims
1. A titanium dioxide grading system, characterized in that, include: The feed bin (1) is provided with a feed inlet (11) and a discharge outlet (12); the feed inlet (11) is connected to a plurality of hydrocyclones (2); the hydrocyclones (2) are located outside the feed bin (1); the hydrocyclones (2) are provided with an overflow outlet (21) and a bottom flow outlet (22); the overflow outlet (21) is connected to the discharge outlet (12), and the bottom flow outlet (22) extends into the bottom flow collection bin (3); And, control module (4), which is configured to: Adjust the concentration of the first titanium dioxide slurry to be graded to the first preset concentration range; The first titanium dioxide slurry is fed into the feed hopper (1) through the feed inlet (11); the first titanium dioxide slurry enters the hydrocyclone (2) through the feed hopper (1); The hydrocyclone (2) is turned on, and the particles in the first titanium dioxide slurry are separated by the interparticle interaction and swirling field characteristics under high concentration. The first overflow is generated and flows from the overflow port (21) to the discharge port (12) of the feed hopper (1), and the first underflow is generated and flows from the underflow port (22) to the underflow collection hopper (3). The first overflow includes: a first titanium dioxide intermediate product containing particles of a first particle size range and a second particle size range; the second particle size range is smaller than the first particle size range; the first underflow includes: a second titanium dioxide slurry containing particles of the first particle size range. The concentration of the first titanium dioxide intermediate product is diluted to a second preset concentration range; the second preset concentration range is smaller than the first preset concentration range. The diluted first titanium dioxide intermediate product is fed into the feed hopper (1) through the feed inlet (11); The hydrocyclone (2) is turned on to separate the particles in the first titanium dioxide intermediate product, so that the generated second overflow flows from the overflow port to the discharge port (12) of the feed hopper (1), and the generated second underflow flows from the underflow port to the underflow collection hopper (3); the second overflow includes: titanium dioxide target product containing particles in the second particle size range; the second underflow includes: third titanium dioxide slurry containing particles in the first particle size range.
2. The titanium dioxide grading system according to claim 1, characterized in that, The feed inlet (11) is connected to the hydrocyclone (2) through the first material transfer pipe (111); The feeding hopper (1) is provided with a second material transfer pipe (112), which is arranged along the height direction of the feeding hopper (1). One end of the second material transfer pipe (112) is connected to the overflow port (21) through the overflow pipe (211); the other end of the second material transfer pipe (112) is connected to the discharge port (12). The underflow outlet (22) is connected to the underflow pipe (221), and the end of the underflow pipe (221) away from the underflow outlet (22) extends into the underflow collection chamber (3).
3. The titanium dioxide grading system according to claim 1, characterized in that, The system also includes: a dilution chamber (5); The control module (4) is further configured as follows: The concentration of the first titanium dioxide slurry to be graded is adjusted to a first preset concentration range using the dilution chamber (5); In addition, the concentration of the first titanium dioxide intermediate product is diluted to a second preset concentration range using the dilution chamber (5).
4. A titanium dioxide grading system according to claim 3, characterized in that, The system also includes: a sand mill (6); The control module (4) is also configured to: Based on the first titanium dioxide slurry, the first titanium dioxide slurry is pre-dispersed using the sand mill (6), and after the pre-dispersed treatment, it is fed into the feed hopper (1). The feed pump speed of the sand mill (6) is adjusted to 450 rpm. Based on the first titanium dioxide intermediate product, the sand mill (6) is used to perform light grinding and depolymerization treatment. After the light grinding and depolymerization treatment, the first titanium dioxide intermediate product is fed into the dilution chamber (5).
5. A titanium dioxide grading system according to claim 4, characterized in that, The control module (4) is also configured to: Based on the second titanium dioxide slurry, the sand mill (6) is used again for pre-dispersion treatment. After the pre-dispersion treatment, the second titanium dioxide slurry is fed into the feed hopper (1). And, obtain a second titanium dioxide intermediate product located in the first particle size range from the target titanium dioxide product; Based on the second titanium dioxide intermediate product and the third titanium dioxide slurry, the second titanium dioxide intermediate product and the third titanium dioxide slurry are subjected to a light grinding and depolymerization process using the sand mill (6). After the light grinding and depolymerization process, they are fed into the dilution chamber (5).
6. A titanium dioxide grading system according to claim 1, characterized in that, The underflow collection chamber (3) includes: The collection bin body (31) is provided with a baffle (311) on the top and an outlet (312) on the bottom.
7. A method for classifying titanium dioxide, applied to a titanium dioxide classification system according to any one of claims 1 to 6, characterized in that, include: Adjust the concentration of the first titanium dioxide slurry to be graded to the first preset concentration range; The first titanium dioxide slurry is fed into the feed hopper through the feed inlet; The first titanium dioxide slurry enters the hydrocyclone through the feed hopper; The hydrocyclone is activated to separate particles in the first titanium dioxide slurry using the interparticle interaction and swirling field characteristics at high concentrations. The resulting first overflow flows from the overflow port to the discharge port of the feed hopper, and the resulting first underflow flows from the underflow port to the underflow collection hopper. The first overflow includes: a first titanium dioxide intermediate product containing particles of a first particle size range and a second particle size range; the second particle size range is smaller than the first particle size range. The first underflow includes: a second titanium dioxide slurry containing particles of the first particle size range. The concentration of the first titanium dioxide intermediate product is diluted to a second preset concentration range; the second preset concentration range is smaller than the first preset concentration range. The diluted first titanium dioxide intermediate product is fed into the feed hopper through the feed inlet; The hydrocyclone is activated to separate the particles in the first titanium dioxide intermediate product, causing the generated second overflow to flow from the overflow port to the discharge port of the feed hopper, and the generated second underflow to flow from the underflow port to the underflow collection hopper; the second overflow includes: titanium dioxide target product containing particles in the second particle size range; the second underflow includes: third titanium dioxide slurry containing particles in the first particle size range.
8. The titanium dioxide grading method according to claim 7, characterized in that, After the step of adjusting the concentration of the first titanium dioxide slurry to be graded to a first preset concentration range, the following steps are included: Based on the first titanium dioxide slurry, a sand mill is used for pre-dispersion treatment.
9. A method for classifying titanium dioxide according to claim 8, characterized in that, Before the step of diluting the concentration of the first titanium dioxide intermediate product to a second preset concentration range, the following steps are included: The feed pump speed of the sand mill is adjusted to 450 rpm, and the first titanium dioxide intermediate product is subjected to light grinding and deagglomeration treatment using the sand mill.
10. A method for classifying titanium dioxide according to claim 9, characterized in that, The method further includes: Based on the second titanium dioxide slurry, the step of pre-dispersion treatment using a sand mill is repeated; And, obtain a second titanium dioxide intermediate product located in the first particle size range from the target titanium dioxide product; Based on the second titanium dioxide intermediate product and the third titanium dioxide slurry, the step of light grinding and deagglomeration treatment using the sand mill is repeated.