An integrated device and process for grinding and activating calcium carbonate

Abstract

This application relates to the technical field of material processing, and in particular to an integrated device and process for grinding and activating calcium carbonate. The device includes a grinding mechanism, an air duct conveying mechanism, an electrostatic emission mechanism, a heating and humidity control mechanism, a composite coating mechanism, and a collection mechanism. The air duct conveying mechanism sequentially connects the grinding mechanism, the heating and humidity control mechanism, the composite coating mechanism, and the collection mechanism. The electrostatic emission mechanism is located outside the air duct conveying mechanism between the grinding mechanism and the heating and humidity control mechanism. The electrostatic emission mechanism is used to emit static electricity into the air duct conveying mechanism. A sprayer is installed inside the composite coating mechanism to spray atomized stearic acid to coat the calcium carbonate powder. This application achieves the following advantages: after grinding, the calcium carbonate powder can be uniformly dispersed without agglomeration, and the powder can fully contact the modifier, improving the product modification effect and achieving efficient powder activation.

Description

Technical Field

[0001] This application relates to the technical field of materials processing, and in particular to an integrated device and process for grinding and activating calcium carbonate. Background Technology

[0002] Calcium carbonate, as an important inorganic filler, has wide applications in numerous industries such as plastics, rubber, and coatings. Its powder properties, such as dispersibility, moisture content, and surface modification effects, play a decisive role in the performance of the products. These properties not only affect the performance of the calcium carbonate products themselves but also have a profound impact on the product quality and production efficiency of downstream industries.

[0003] For grinding powders, common methods include using dry grinding equipment such as vertical mills and ring roller mills. These devices can grind calcium carbonate raw materials to the required particle size. In the surface modification process, most existing modification equipment uses stirring or simple spray coating methods to mix modifiers such as stearic acid with the powder. This can, to a certain extent, complete the processing of calcium carbonate powder.

[0004] In existing processes using dry grinding equipment, some powder will be blocked and accumulate on the uneven inner walls, whether in the transport pipeline or in the intermediate equipment. This accumulation or adhesion to the inner wall surface can lead to agglomeration over time. The lack of immediate dispersion means results in insufficient contact between particles and modifiers during subsequent modification, leading to poor product modification. Furthermore, the modification process requires heating the powder from room temperature to a specified range, resulting in high energy consumption. Summary of the Invention

[0005] In order to ensure that the powder is evenly dispersed and does not agglomerate, so that the powder and the modifier can be in full contact, thereby improving the product modification effect and reducing energy consumption during modification, the purpose of this application is to provide an integrated device and process for grinding and activating calcium carbonate.

[0006] In a first aspect, this application provides an integrated device for grinding and activating calcium carbonate, which adopts the following technical solution: It includes a grinding mechanism, an air conveying mechanism, an electrostatic emission mechanism, a heating and humidity control mechanism, a composite coating mechanism, and a collection mechanism; The air duct conveying mechanism connects the grinding mechanism, heating and humidity control mechanism, composite coating mechanism and collection mechanism in sequence. The electrostatic emission mechanism is located outside the air duct conveying mechanism between the grinding mechanism and the heating and humidity control mechanism, and the electrostatic emission mechanism is used to emit static electricity into the air duct conveying mechanism. The composite coating mechanism is equipped with a sprayer for spraying atomized stearic acid to coat calcium carbonate powder.

[0007] By adopting the above technical solution, an electrostatic charge of the same polarity is applied to the powder as it leaves the grinding mechanism and enters the air duct, so that the powder remains in a highly dispersed single-particle state before entering the drying and coating stages, preventing agglomeration. This ensures that the powder and modifier have sufficient contact, improving the product modification effect. At the same time, the residual heat of the freshly ground powder is utilized to directly heat it to the specified temperature without the need for reheating from room temperature, which can reduce energy consumption and lower costs.

[0008] Optionally, the grinding mechanism is provided with an air inlet at the bottom, which is connected to a blower for delivering vertically upward airflow into the grinding mechanism.

[0009] By adopting the above technical solution, the upward airflow can lift the powder, promote the collision and classification of particles in the grinding chamber, and enable qualified fine powder to be carried out by the airflow in time to prevent over-grinding. On the other hand, the airflow directly starts the pneumatic conveying of powder in the air duct, integrating grinding and conveying, simplifying the equipment structure, reducing energy consumption, and improving the continuity of the system.

[0010] Optionally, the electrostatic emission mechanism includes an electrostatic emission port, which is disposed on the side wall of the air duct conveying mechanism and faces the powder inside the air duct conveying mechanism.

[0011] By adopting the above technical solution, precise and efficient electrostatic treatment of powder flow is achieved. When the powder just leaves the grinding mechanism and enters the air duct, a similar electrostatic charge is applied. Coulomb repulsion effectively prevents newly formed fine particles from agglomerating due to van der Waals forces, allowing the agglomerated powder to disperse rapidly before entering the drying and coating stages. Furthermore, the dispersed state is maintained under the synergistic effect of the airflow in the air duct, improving the uniformity of powder processing in subsequent processes.

[0012] Optionally, a monitoring mechanism is also included, comprising a powder moisture monitoring component and a turbidity monitoring component. The moisture monitoring component is installed in the heating and humidity control mechanism to monitor the moisture content of the powder, and the turbidity monitoring component is installed in the composite coating mechanism to monitor the turbidity of the powder.

[0013] By adopting the above technical solutions, the production process is elevated from experience-based operation to a precise and controllable intelligent level. By monitoring the moisture content of the dried powder, the drying intensity can be adjusted in real time to avoid over-drying or under-drying. By monitoring the turbidity of the powder in the coating area, when the turbidity is low, it indicates that some of the powder inside has agglomerated, reducing the overall amount, and the agglomerated powder needs to be dispersed. On the other hand, if the turbidity is too high, it indicates that the powder has been over-dispersed, which will affect subsequent processes. In this case, it is necessary to reduce further dispersion of the powder.

[0014] Optionally, the moisture monitoring component includes a moisture meter, the probe of which is positioned vertically toward the powder flow within the heating and humidity control mechanism.

[0015] By adopting the above technical solution, rapid, non-contact, and online accurate measurement of powder moisture is achieved. Infrared spectroscopy can specifically identify water molecules, resulting in high measurement accuracy; the non-contact installation does not interfere with powder flow; and the vertical detection method can obtain more representative overall information on the powder flow. This real-time data provides a direct basis for the automatic feedback control of the heating and humidity control mechanism.

[0016] Optionally, an axial flow fan is also included, which is installed in the air duct conveying mechanism between the heating and humidity control mechanism and the composite coating mechanism. Its high-speed rotating impeller is used to break up powder agglomerates and drive the powder forward.

[0017] By adopting the above technical solution, during long-term use, some uneven parts of the inner wall of the pipe will cause powder to accumulate, forming larger particles. These particles will then fall off and mix with other powders. The high-speed rotating impeller of the axial flow fan can effectively disperse a small number of soft agglomerated particles. On the other hand, the strong suction and thrust generated by the fan can ensure that the powder is uniformly and stably transported to the coating area, creating a uniform and dispersed powder environment for surface coating.

[0018] Optionally, the bottom of the collecting mechanism is provided with a conveying assembly, which includes a spiral conveying rod and a drive motor, with the output end of the drive motor connected to the end of the spiral conveying rod.

[0019] By adopting the above technical solution, the powder can be discharged from the collector in a controlled and stable manner. The screw conveyor has good sealing performance, which can prevent the finished powder from getting damp or leaking in the final stage; its continuous conveying capacity matches the upstream production cycle, avoiding blockage; at the same time, the screw conveyor has a certain loosening effect on the powder, which helps to alleviate the slight compaction that may form at the bottom of the collector, facilitating subsequent processing.

[0020] Optionally, a vibrating screening assembly is also included, which is located downstream of the collecting mechanism. The vibrating screening assembly includes a screening funnel, a vibrating motor, and a discharge port. The vibrating motor is connected to the side wall of the screening funnel, and the discharge port is located at the bottom of the screening funnel.

[0021] By adopting the above technical solution, the vibrating screen can effectively remove the very small amount of stearic acid agglomerates that may be generated during the coating process, as well as coarse or hard calcium carbonate particles that are not completely dispersed, ensuring that the particle size distribution of the final product meets the standards and the coating is uniform. The material over the screen can be collected separately for reprocessing or other uses, improving the utilization rate of raw materials and ensuring the uniformity and high quality of the finished products.

[0022] Secondly, the integrated grinding and activation process for calcium carbonate provided in this application adopts the following technical solution: Includes the following steps: S1: Grinding and electrostatic dispersion: The heavy calcium carbonate raw material is ground, and the ground powder enters the air duct conveying mechanism from the discharge port; the same electrostatic charge is applied to the surface of the powder in the air duct conveying mechanism; S2: Heating and drying: Heating the dispersed powder to remove moisture; S3: Disperse and deagglomerate: Disperse the calcium carbonate agglomerates that have formed in the channel and break up the powder agglomeration; S4: Surface coating activation: Stearic acid is heated to 105℃ to liquefy it, and the liquid stearic acid is sprayed onto the surface of the powder to coat the powder particles and activate the powder. S5: Online monitoring and feedback control: Real-time monitoring of the moisture content of the dried powder and / or the coating state of the coated powder, and adjustment of heating power and / or atomization parameters based on the monitoring results; S6: Collection and Screening: The activated powder is sent to a dust collector for collection; the powder in the dust collector is then sent to a vibrating screen for filtration to remove particles and stearic acid agglomerates. The qualified powder that passes through is collected and packaged, and the residue is stored separately.

[0023] By adopting the above technical solution, an optimal operation sequence and method integration for achieving efficient and high-quality activated calcium carbonate production were defined. The process integrates key innovative steps such as electrostatic dispersion, online monitoring feedback and control into the traditional process. This not only ensures that the powder maintains good dispersibility throughout the entire process, but also allows the ground powder to retain its residual heat before direct heating, reducing energy consumption. Furthermore, real-time monitoring and adjustment enable optimized closed-loop control of process parameters, ultimately allowing stearic acid to completely encapsulate the powder, achieving full activation and producing high-performance activated calcium carbonate products.

[0024] In summary, this application includes at least one of the following beneficial technical effects: 1. When the powder leaves the grinding mechanism and enters the air conveying mechanism, a static charge of the same polarity is applied to keep the powder in a highly dispersed single-particle state before entering the drying and coating stages, preventing agglomeration. This ensures sufficient contact between the powder and the modifier, improving the product modification effect. At the same time, the residual heat of the freshly ground powder is utilized to directly heat it to the specified temperature without reheating from room temperature, which can reduce energy consumption and lower costs. 2. Utilize technologies such as online monitoring to monitor powder moisture and turbidity in real time, and automatically adjust heating power and coating parameters accordingly, transforming the production process from experience-driven to data-driven precision control; 3. The forced deagglomeration and conveying by the axial flow fan ensures that the powder remains in a uniform and stable ideal state during key processes, thereby significantly improving the stability and consistency of product quality; Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of the integrated calcium carbonate grinding and activation device; Figure 2 This is a front view schematic diagram of an integrated calcium carbonate grinding and activation device; Figure 3 These are partial cross-sectional schematic diagrams of the collection mechanism and structural schematic diagrams of the vibration screening components; Figure 4 This is another schematic diagram of an integrated calcium carbonate grinding and activation device; In the picture, 1. Grinding mechanism; 11. Air inlet; 2. Air duct conveying mechanism; 21. Air duct; 3. Electrostatic emission mechanism; 31. Electrostatic emission port; 32. Electrostatic generator; 4. Heating and humidity control mechanism; 5. Composite coating mechanism; 51. Sprayer; 6. Collection mechanism; 61. Conveying assembly; 611. Screw conveyor; 612. Drive motor; 7. Axial flow fan; 8. Vibrating screening assembly; 81. Screening funnel; 82. Vibrating motor; 83. Discharge port. Detailed Implementation

[0026] The following is in conjunction with the appendix Figure 1 - Appendix Figure 4 This application will be described in further detail below.

[0027] Example 1: An integrated device for grinding and activating calcium carbonate, referring to... Figure 1 The system includes a grinding mechanism 1, an air duct conveying mechanism 2, an electrostatic emission mechanism 3, a heating and humidity control mechanism 4, a composite coating mechanism 5, and a collection mechanism 6. The air duct conveying mechanism 2 connects the grinding mechanism 1, the heating and humidity control mechanism 4, the composite coating mechanism 5, and the collection mechanism 6 sequentially. The electrostatic emission mechanism 3 is located outside the air duct conveying mechanism 2, between the grinding mechanism 1 and the heating and humidity control mechanism 4. The electrostatic emission mechanism 3 emits static electricity into the air duct conveying mechanism 2, utilizing charge repulsion to fully disperse the powder particles and prevent agglomeration due to van der Waals forces, providing a good foundation for subsequent processing steps. The composite coating mechanism 5 is equipped with a sprayer 51, which sprays atomized stearic acid to coat the calcium carbonate powder, increasing the probability of mixing and contact between the stearic acid and the powder, resulting in more uniform coating.

[0028] Specifically, the grinding mechanism 1 includes a grinding chamber and grinding components. The grinding chamber is a relatively enclosed space used to contain calcium carbonate raw materials and perform grinding operations. The grinding chamber can be made of wear-resistant materials, such as high-chromium cast iron, to improve its service life. The grinding components can be grinding rollers and grinding discs of a vertical mill, etc. The grinding rollers roll on the grinding disc, grinding the calcium carbonate raw materials to the target particle size through squeezing and grinding action. The grinding rollers are usually made of high-strength alloy steel, and the surface is specially treated to improve their wear resistance and grinding efficiency.

[0029] Furthermore, refer to Figure 2 The grinding mechanism 1 has an air inlet 11 at its bottom, which is connected to a blower to deliver vertically upward airflow into the grinding mechanism 1. The airflow can lift the ground powder, making it easier for it to enter the air duct conveying mechanism 2 and then into the heating and humidity control mechanism 4.

[0030] Specifically, the air duct conveying mechanism 2 includes an air duct 21 and a supporting structure. The inner wall of the air duct 21 can be smoothed to reduce the adhesion and accumulation of powder inside the duct. The supporting structure is used to fix the air duct 21 and keep it stable. The supporting structure can be a metal bracket, connected to the air duct 21 by welding or bolting.

[0031] Furthermore, refer to Figure 2 The electrostatic emission mechanism 3 includes an electrostatic emission port 31 and an electrostatic generator 32. The electrostatic emission port 31 is located on the side wall of the air duct conveying mechanism 2 and faces the powder inside the air duct conveying mechanism 2. The electrostatic emission port 31 can be a needle-shaped electrode. When the electrostatic generator 32 generates static electricity, the static electricity is emitted to the surface of the powder inside the air duct 21 through the needle-shaped electrode. The electrostatic generator 32 can be a pulsed electrostatic generator 32, which can generate high-voltage electrostatic pulses, causing the powder surface to quickly become charged with the same charge.

[0032] Specifically, the heating and humidity control mechanism 4 includes a heating chamber and a heating component. The heating chamber is a cavity with good thermal insulation properties to reduce heat loss. The heating chamber can have a double-layer structure, with insulation material, such as rock wool, filling the space between. The heating component can be an electrically heated screen tube or a microwave heating device.

[0033] Furthermore, a downward-flowing hot air blower is installed at the top of the heating and humidity control mechanism 4. This blower evenly onto the powder within the heating chamber, accelerating moisture evaporation and improving heating and humidity control. Simultaneously, it blows the powder towards the outlet located below, from which it then enters the pipeline. This further provides the power for transporting the powder within the device.

[0034] Specifically, the composite coating mechanism 5 includes a mixing chamber and a sprayer 51. When the dried powder is fed into the mixing chamber, the sprayer 51 atomizes the liquid stearic acid into tiny droplets and sprays them onto the surface of the powder in the mixing chamber, thereby coating and activating it. The sprayer 51 can be an ultrasonic atomizer, which can atomize the liquid stearic acid into tiny droplets of 1-5 μm, which are injected into the cyclone mixing chamber by a carrier gas at a pressure of 0.3 MPa.

[0035] The composite coating mechanism 5 also includes a coating agent addition component, which comprises a raw material silo, a heated liquefaction unit, and a support. The raw material silo is typically funnel-shaped and is used to store solid stearic acid. The heated liquefaction unit generally uses electric heating and has internal heating tubes that can heat the solid stearic acid to 105°C to liquefy it. The support, welded from metal tubing, supports the raw material silo and the heated liquefaction unit, ensuring their stable placement. The raw material silo is located above the heated liquefaction unit, allowing the solid stearic acid to fall naturally into the unit by gravity for liquefaction. This gravity-feeding method is simple, efficient, and requires no additional power equipment.

[0036] Specifically, refer to Figure 3 The collecting mechanism 6 includes a dust collector for collecting processed calcium carbonate powder. The dust collector can be sealed to prevent powder leakage. A conveying assembly 61 is also located at the bottom of the collecting mechanism 6. The conveying assembly 61 includes a screw conveyor 611 and a drive motor 612, with the output end of the drive motor 612 connected to the end of the screw conveyor 611. When the coated powder enters the dust collector and settles, it falls into the conveying mechanism. At this time, the screw conveyor 611 rotates under the drive of the drive motor 612, pushing the powder in the dust collector to the outlet. The screw conveyor 611 can be made of stainless steel with a smooth surface to reduce powder adhesion and accumulation.

[0037] This embodiment also includes a monitoring mechanism, which comprises a powder moisture monitoring component and a turbidity monitoring component. The moisture monitoring component is disposed within the heating and humidity control mechanism 4 and is used to monitor the moisture content of the powder. The turbidity monitoring component is disposed within the composite coating mechanism 5 and is used to monitor the turbidity of the powder. The moisture monitoring component includes a moisture meter, the probe of which is positioned vertically toward the powder flow within the heating and humidity control mechanism 4.

[0038] Moisture analyzer principle: OH bonds in (H2O); 1. 1450nm wavelength: corresponds to the combined absorption of the "stretching vibration + bending vibration" of the OH bond; 2. 1940nm wavelength: corresponds to the combined absorption of the "antisymmetric stretching vibration + symmetric stretching vibration" of the OH bond; 3. Calcium carbonate (CaCO3) has almost no absorption at wavelengths of 1450nm and 1940nm, therefore these two wavelengths can "avoid the interference of calcium carbonate" and only measure the moisture in the powder. Monitoring points: One online moisture analyzer can be installed inside the heating and humidity control mechanism 4 and at its outlet to double verify moisture stability.

[0039] The moisture meter data is integrated into the production line PLC control system: if the moisture content is too high, the dryer hot air temperature / hot air volume is automatically increased; if the moisture content is too low, the drying parameters are appropriately reduced to save energy. The turbidity monitoring component uses a light scattering online laser turbidity meter. This device monitors the turbidity value of the powder in the mixing chamber in real time through the principle of light scattering, accurately characterizing the powder dispersion state and providing real-time data for adjusting the process parameters of the subsequent dispersing mechanism.

[0040] In addition, this embodiment also includes an axial flow fan 7, which is disposed within the air duct conveying mechanism 2 between the heating and humidity control mechanism 4 and the composite coating mechanism 5. Its high-speed rotating impeller is used to break up powder agglomerates and drive the powder forward. The axial flow fan 7 includes a protective shell and fan blades disposed within the protective shell. The protective shell is generally made of metal, such as stainless steel or carbon steel, possessing certain strength and corrosion resistance, and protecting the fan blades from damage by external factors. The fan blades are usually made of aluminum alloy or plastic, and are streamlined in shape to reduce wind resistance and improve the fan's working efficiency. A gap of 0.5-2mm is left between the edge of the fan blades and the inner wall of the protective shell. This gap ensures that the fan blades do not rub against the protective shell during rotation and reduces air leakage, thus improving the fan's performance.

[0041] Furthermore, the axial flow fan 7 works in conjunction with the aforementioned turbidity monitoring component. When the turbidity is low, it indicates that some of the powder particles have agglomerated into larger particles. In this case, feedback is sent to the axial flow fan 7, increasing its power to disperse the agglomerated particles. If the turbidity is high, the power of the axial flow fan 7 can be reduced, thereby reducing energy consumption. The axial flow fan 7 can be a centrifugal axial flow fan 7, capable of generating strong airflow and vortices to effectively disperse powder agglomerates.

[0042] Finally, refer to Figure 3This embodiment also includes a vibrating screening assembly 8, which is located downstream of the collecting mechanism 6. The vibrating screening assembly 8 includes a screening funnel 81, a vibrating motor 82, and a discharge port 83. The vibrating motor 82 is connected to the side wall of the screening funnel 81, and the discharge port 83 is located at the bottom of the screening funnel 81. A buffer spring is also provided around the screening funnel 81 to prevent the entire support frame from vibrating when the screening funnel 81 vibrates, thereby preventing mechanical damage to the device. The vibrating motor 82 vibrates the screening funnel 81, causing the powder to be screened inside the funnel. Qualified powder is discharged from the discharge port 83, while the residue remains in the funnel for further processing.

[0043] In addition to the above methods, there is another structural method, see [link / reference]. Figure 4 After being ground into powder, the discharge port of the grinding mechanism 1 is connected to a relatively thick air duct 21, and the other end of the air duct 21 is directly connected to the dust collector. The powder is transported from the grinding mechanism 1 to the dust collector. The intermediate components, such as the electrostatic emission mechanism 3, the heating and humidity control mechanism 4, and the composite coating mechanism 5, can be reduced in size and placed inside the air duct 21. For example, the electrostatic emission port 31 of the electrostatic emitter is connected to the side wall of the air duct 21 to directly release static electricity into the air duct 21. Alternatively, an electrostatic rod or electrostatic emission plate can be placed inside the air duct 21 and then connected by wires. After passing through the heating and humidity control mechanism 4, which can be an industrial heating grid or other heating devices, the heating and humidity control function can be achieved.

[0044] Next, the area passes through the composite coating mechanism 5, which is located outside the air duct 21. Simply insert the sprayer 51 through the side wall of the air duct 21 to spray atomized stearic acid into the air duct 21 for coating and activation. The resulting particles are then blown into the dust collector by the hot air inside the air duct 21, where they are collected and vibrated for screening. The monitoring mechanism can still be placed in the corresponding area for monitoring, as per the previous scheme. A rotating shaft is installed in front of the composite coating mechanism 5, with blades such as scrapers on its circumference to achieve the dispersing function. This combination achieves the function of the axial flow fan 7 in dispersing large particles.

[0045] Finally, because hot air is continuously supplied from the grinding mechanism 1 into the air duct 21 and the dust collector, the air pressure inside the air duct 21 and the dust collector is relatively high. Therefore, a return air duct can be connected to the top of the dust collector, with the other end connected to the side wall of the heating and humidity control mechanism 4 area. The return air duct in the heating and humidity control mechanism 4 area is designed with an incline, so that the direction of the returning hot air after entering the air duct 21 is the same as the direction of the initial hot air supply. This allows for the recycling of hot air, reducing energy consumption, further promoting dust transport, and easing the air pressure inside the dust collector. Compared with the previous structural scheme, this design is more integrated and greatly reduces the cost of each mechanism, effectively reducing energy consumption and making the production process more integrated.

[0046] The implementation principle of this embodiment is as follows: This integrated calcium carbonate grinding and activation device achieves integrated processing of heavy calcium carbonate powder from grinding to final collection through the coordinated work of various mechanisms. Grinding mechanism 1 grinds the calcium carbonate raw material to the target particle size; electrostatic emission mechanism 3 disperses the ground powder; heating and humidity control mechanism 4 precisely controls the moisture content of the powder; composite coating mechanism 5 achieves uniform coating of stearic acid on the powder; monitoring mechanism provides real-time feedback on key parameters during processing; axial flow fan 7 breaks up powder agglomerates and drives powder conveying; and collection mechanism 6 and vibrating screening assembly 8 collect and screen the processed powder. The entire device fully utilizes the residual heat of the ground powder, reducing energy consumption, improving powder dispersibility, moisture control accuracy, and stearic acid coating uniformity, reducing stearic acid usage, and improving processing economy and product qualification rate.

[0047] Example 2: An integrated process for grinding and activating calcium carbonate, comprising the following steps: S1: Grinding and Electrostatic Dispersion: The heavy calcium carbonate raw material is ground using dry grinding equipment such as vertical mills, ring roller mills, or ball mills. Taking a vertical mill as an example, the heavy calcium carbonate raw material is placed in the grinding chamber, and the grinding rollers roll on the grinding disc. Through compression and grinding, the raw material is ground to the target particle size. The ground powder enters the air duct 21 from the discharge port. At this time, the electrostatic emission mechanism 3 applies a static charge of the same charge to the surface of the powder in the air duct 21. The electrostatic emission mechanism 3 can be the electrostatic emission port 31 or electrostatic emission plate in the above embodiment, etc. It uses the charge repulsion effect to fully disperse the powder particles, avoiding the agglomeration of powder due to van der Waals forces, and providing a good foundation for subsequent processing steps.

[0048] S2: Heating and Drying: The dispersed powder is rapidly heated to remove moisture. A heating and humidity control mechanism 4 or an electrically heated screen tube is installed at the inlet of the air duct 21 to heat the flowing heavy calcium carbonate raw material. During the heating process, a hot air blower installed at the top of the heating and humidity control mechanism 4 blows air downwards to accelerate the evaporation of moisture. The moisture content of the powder is precisely controlled below 500 ppm, while the temperature inside the air duct 21 is stabilized at around 130℃. This step utilizes the residual heat of the powder itself (40-70℃) after grinding, eliminating the need for reheating from room temperature and significantly reducing energy consumption.

[0049] S3: Dispersion and Deagglomeration: This process disperses the small number of large calcium carbonate agglomerates that have formed within the channel, breaking up powder clusters. An axial flow fan 7 is installed in the air duct conveying mechanism 2 between the heating and humidity control mechanism 4 and the composite coating mechanism 5. The high-speed rotating impeller of the axial flow fan 7 generates a powerful airflow and vortex, dispersing the agglomerated powder particles. The axial flow fan 7 can be a centrifugal axial flow fan 7, with a specially designed impeller that effectively disperses powder agglomerates, providing a more uniform powder for subsequent coating processes.

[0050] S4: Surface Coating Activation: Stearic acid is heated to 105℃ to liquefy it. The heating equipment can be an electric heating furnace, etc. The liquid stearic acid is atomized into 1-5um microdroplets by an ultrasonic atomizer. The atomized stearic acid is sprayed onto the powder surface by the sprayer 51 in the composite coating mechanism 5 to complete the coating process and achieve efficient powder activation.

[0051] S5: Online Monitoring and Feedback Control: Real-time monitoring of the moisture content of the dried powder and / or the coating state of the coated powder, and adjustment of heating power and / or atomization parameters based on the monitoring results. The moisture monitoring component collects the absorption peak intensity of the -OH groups of the powder at 3400 cm⁻¹ in real time during the heating and humidity control section, inverts the powder moisture content using the PLS algorithm, and feeds back to control the power of the heating device. The turbidity monitoring component collects the powder turbidity in real time during the composite coating section and feeds back to control the axial flow fan 7 to further disperse the aggregated powder, achieving closed-loop precise control of moisture content and coating rate.

[0052] S6: Collection and Screening: The activated powder is sent to the dust collector for collection. The powder in the dust collector is conveyed to the discharge port 83 by the screw conveyor 611 and enters the screening funnel 81. Finally, it is filtered through the screening funnel 81 to remove coarse particles and stearic acid agglomerates from the powder. The residue is stored separately.

[0053] The implementation principle of this application embodiment is as follows: This integrated calcium carbonate grinding and activation process achieves efficient processing of heavy calcium carbonate powder through the orderly execution of each step. From grinding to final collection and screening, each step is closely linked and works in concert. The grinding and electrostatic dispersion steps prevent powder agglomeration, the heating and drying steps precisely control the moisture content of the powder, the dispersing and deagglomeration steps provide uniform powder for coating, the surface coating and activation steps improve the uniformity of stearic acid coating, the online monitoring and feedback control steps realize automated control of the processing process, and the collection and screening steps improve the product qualification rate. The entire process makes full use of the residual heat of the powder after grinding, reduces energy consumption, reduces the amount of stearic acid used, and improves processing economy and product quality.

[0054] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, all equivalent changes made to the structure, shape, and principle of this application should be covered within the scope of protection of this application.

Claims

1. A calcium carbonate grinding and activation integrated device, characterized in that, It includes a grinding mechanism (1), an air duct conveying mechanism (2), an electrostatic emission mechanism (3), a heating and humidity control mechanism (4), a composite coating mechanism (5), and a collection mechanism (6). The air duct conveying mechanism (2) connects the grinding mechanism (1), the heating and humidity control mechanism (4), the composite coating mechanism (5), and the collection mechanism (6) in sequence; The electrostatic emission mechanism (3) is located outside the air duct conveying mechanism (2) between the grinding mechanism (1) and the heating and humidity control mechanism (4). The electrostatic emission mechanism (3) is used to emit static electricity into the air duct conveying mechanism (2). The composite coating mechanism (5) is equipped with a sprayer (51) for spraying atomized stearic acid to coat calcium carbonate powder.

2. The integrated calcium carbonate grinding and activation device according to claim 1, characterized in that, The grinding mechanism (1) is provided with an air inlet (11) at the bottom. The air inlet (11) is connected to a blower and is used to deliver vertically upward airflow into the grinding mechanism (1).

3. The integrated calcium carbonate grinding and activation device according to claim 1, characterized in that, The electrostatic emission mechanism (3) includes an electrostatic emission port (31), which is located on the side wall of the air duct conveying mechanism (2) and faces the powder inside the air duct conveying mechanism (2).

4. The integrated calcium carbonate grinding and activation device according to claim 1, characterized in that, It also includes a monitoring mechanism, which includes a powder moisture monitoring component and a turbidity monitoring component. The moisture monitoring component is installed in the heating and humidity control mechanism (4) and is used to monitor the moisture content of the powder. The turbidity monitoring component is installed in the composite coating mechanism (5) and is used to monitor the turbidity of the powder.

5. The integrated calcium carbonate grinding and activation device according to claim 4, characterized in that, The moisture monitoring component includes a moisture meter, the probe of which is set vertically toward the powder flow inside the heating and humidity control mechanism (4).

6. The integrated calcium carbonate grinding and activation device according to claim 1, characterized in that, It also includes an axial flow fan (7), which is installed in the air duct conveying mechanism (2) between the heating and humidity control mechanism (4) and the composite coating mechanism (5). Its high-speed rotating impeller is used to break up powder agglomerates and drive the powder forward.

7. The integrated calcium carbonate grinding and activation device according to claim 1, characterized in that, The bottom of the collecting mechanism (6) is provided with a conveying assembly (61), which includes a spiral conveying rod (611) and a drive motor (612). The output end of the drive motor (612) is connected to the end of the spiral conveying rod (611).

8. The integrated calcium carbonate grinding and activation device according to claim 1, characterized in that, It also includes a vibration screening assembly (8), which is located downstream of the collection mechanism (6). The vibration screening assembly (8) includes a screening funnel (81), a vibration motor (82), and a discharge port (83). The vibration motor (82) is connected to the side wall of the screening funnel (81), and the discharge port (83) is located at the bottom of the screening funnel (81).

9. A calcium carbonate grinding and activation integrated process, characterized in that, Includes the following steps: S1: Grinding and electrostatic dispersion: The heavy calcium carbonate raw material is ground, and the ground powder enters the air conveying mechanism (2) from the discharge port; the same electrostatic charge is applied to the surface of the powder in the air conveying mechanism (2); S2: Heating and drying: Heating the dispersed powder to remove moisture; S3: Disperse and deagglomerate: Disperse the calcium carbonate agglomerates that have formed in the channel and break up the powder agglomeration; S4: Surface coating activation: Stearic acid is heated to 105℃ to liquefy it, and the liquid stearic acid is sprayed onto the surface of the powder to coat the powder particles and activate the powder. S5: Online monitoring and feedback control: Real-time monitoring of the moisture content of the dried powder and / or the coating state of the coated powder, and adjustment of heating power and / or atomization parameters based on the monitoring results; S6: Collection and Screening: The activated powder is sent into a dust collector for collection; The powder in the dust collector is then conveyed to the vibrating screen for filtration to remove particles and stearic acid agglomerates. The qualified powder that passes through is collected and packaged, while the residue is stored separately.

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