Coating slurry circulating system and circulating method

Abstract

The coating slurry circulating system comprises a PLC control system, a coating head, a material box, a dynamic homogenizing transit cylinder, a pneumatic pump and a filter, the PLC control system is electrically connected with the dynamic homogenizing transit cylinder, the coating head, the filter and the pneumatic pump, a feeding port of the coating head is connected with a discharging port of the material box through a pipeline, and the feeding port of the coating head is connected with a discharging port of the material box through a pipeline. The dynamic homogenizing transit cylinder is located below the material box, a feeding port of the pneumatic pump is connected with a discharging port of the dynamic homogenizing transit cylinder through a pipeline, a discharging port of the pneumatic pump is connected with a feeding port of the filter through a pipeline, and slurry in the material box can flow into the dynamic homogenizing transit cylinder. The method has the advantages that the pollution to the working environment in the coating process is reduced, the utilization rate of the slurry can be improved to achieve the effect of reducing the cost, meanwhile, the slurry is prevented from settling, agglomerating and skinning through circular flowing of the slurry, high uniformity and stability of slurry components are ensured, and the coating effect is ensured.

Description

Technical Field

[0001] This invention relates to the field of coating, specifically to a coating slurry recycling system and recycling method. Background Technology

[0002] Coating processes are widely used in lithium batteries, photovoltaic modules, electronic films, packaging materials, and many other fields. The core of this process is to uniformly coat a slurry with specific properties onto the surface of a substrate, forming a coating with functional characteristics. The uniformity and stability of this coating directly determine the quality and performance of the final product. During the coating process, the supply and management of the slurry are always key factors affecting process stability and product yield. In traditional coating processes, the slurry is typically supplied using a "one-time delivery + static storage" model: the slurry is directly pumped from the storage tank to the coating head, and excess slurry overflowing from the coating head is mostly discarded. This model not only causes waste but also has many drawbacks: First, slurry not used immediately during the coating process is prone to sedimentation and stratification due to differences in the density of solid and liquid components, or solvent evaporation, resulting in uneven slurry concentration. This leads to problems such as uneven coating thickness and localized performance failure during subsequent coating processes. This is especially problematic for applications with extremely high requirements for slurry uniformity, such as lithium battery electrode coating and high-precision electronic thin film coating. Such issues can directly cause product scrap and significantly reduce production yield. Second, the direct disposal of excess slurry that is not recycled not only increases raw material costs but also generates a large amount of industrial waste, which is inconsistent with the current industry development trend of green production and energy conservation and emission reduction. In addition, the traditional supply model lacks an effective slurry circulation and control mechanism. When process parameters such as coating speed and coating thickness are adjusted, the slurry delivery volume is difficult to match quickly, easily leading to insufficient supply or excessive overflow. It cannot achieve intelligent control, resulting in interruptions in the coating process or waste of substrate, affecting production efficiency.

[0003] Therefore, it is necessary to provide a coating slurry circulation system and circulation method. Summary of the Invention

[0004] The present invention provides a coating slurry circulation system and circulation method, which effectively solves the problems of existing slurry waste, easy sedimentation and stratification, uneven concentration, and inability to achieve automatic flow control.

[0005] The technical solution adopted in this invention is: A coating slurry circulation system includes a PLC control system, a coating head, a slurry box, a dynamic homogenizing transfer cylinder, a pneumatic pump, and a filter. The PLC control system is electrically connected to the dynamic homogenizing transfer cylinder, the coating head, the filter, and the pneumatic pump. The inlet of the coating head is connected to the outlet of the slurry box via a pipeline. The dynamic homogenizing transfer cylinder is located below the slurry box. The inlet of the pneumatic pump is connected to the outlet of the dynamic homogenizing transfer cylinder via a pipeline. The outlet of the pneumatic pump is connected to the inlet of the filter via a pipeline. The slurry in the slurry box can also flow into the dynamic homogenizing transfer cylinder.

[0006] Furthermore, a temperature control module is also installed inside the dynamic homogenizing transfer cylinder. The temperature control module is electrically connected to the PLC system and is used to heat the slurry inside the homogenizing transfer cylinder.

[0007] Furthermore, a temperature detection module is also installed inside the dynamic homogenizing transfer cylinder. The temperature detection module is electrically connected to the PLC system and is used to detect the temperature of the slurry inside the homogenizing transfer cylinder.

[0008] Furthermore, the dynamic homogenizing transfer cylinder is also equipped with a stirring module, an online viscosity sensor, and a density meter. The stirring module includes a mounting frame fixedly installed inside the homogenizing transfer cylinder, a rotating shaft mounted on the mounting frame, several blades mounted at the lower end of the rotating shaft, and a motor mounted on the mounting frame for driving the rotating shaft to rotate. The motor, the online viscosity sensor, and the density meter are electrically connected to the PLC system.

[0009] Furthermore, the motor drives the rotating shaft to rotate, the rotating shaft drives the blades to rotate, and the rotation of the blades stirs the slurry in the dynamic homogenizing rotating drum.

[0010] Furthermore, the height between the material box and the transfer cylinder is no higher than 1m.

[0011] Furthermore, the material box includes a box body, an overflow pipe disposed on one side of the box body, and a discharge pipe disposed on the box body. The discharge pipe is connected to the coating head. The connection point between the overflow pipe and the box body is higher than the connection point between the discharge pipe and the box body. The lower end of the overflow pipe is in contact with the inner wall of the dynamic homogenizing transfer cylinder.

[0012] Furthermore, the slurry in the material box first flows along the discharge pipe to the coating head, and the excess slurry flows along the return pipe into the dynamic homogenizing transfer cylinder.

[0013] Furthermore, the overflow pipe is a soft pipe.

[0014] A coating slurry circulation method, using the aforementioned coating slurry circulation system, includes the following steps: S1, injecting the slurry into a dynamic homogenizing transfer cylinder; S2, starting a pneumatic pump, causing the slurry in the dynamic homogenizing transfer cylinder to enter a filter for filtration, and the slurry after filtration flows into a material box; S3, a portion of the slurry in the material box is supplied to the coating head, and the remaining portion is returned to the dynamic homogenizing transfer cylinder.

[0015] Beneficial effects of the invention: The entire coating slurry circulation system can recover and reuse excess coating slurry, thereby achieving slurry circulation. This reduces pollution to the working environment during the coating process and improves the utilization rate of the slurry, thus reducing costs. At the same time, the circulation of the slurry prevents sedimentation, agglomeration, and skinning, ensuring the high uniformity and stability of the slurry components and guaranteeing the coating effect.

[0016] Continuous and stable circulation eliminates stagnation zones in the conveying pipes and cavities, avoiding coating defects such as streaks, vertical lines, and uneven thickness caused by localized variations in slurry viscosity and solid content. This invention enables the production of products with uniform thickness, smooth surfaces, and no defects, significantly improving product yield and consistency.

[0017] The system achieves a fully closed-loop circulation from the feed tank to the coating die and its return pipeline, avoiding prolonged static storage and curing of the slurry within the equipment. Especially during non-production periods such as roll changes and shutdowns, the slurry continues to circulate at a low speed within the system, maintaining its activity. It can be quickly put into use after restarting, achieving almost "zero waste" of the slurry.

[0018] The overflow pipe uses gravity overflow to recover excess slurry from the slurry box, eliminating the need for mechanical scrapers and avoiding shearing damage to the slurry structure and potential damage to the substrate. It is especially suitable for coating scenarios with high precision and high surface requirements.

[0019] By using online sensors and PLC controllers, the system can achieve real-time sensing and active control of the slurry status, enabling it to be adaptive. By controlling the output pressure of the pneumatic pump to precisely control the flow rate of the slurry in the slot, the system can respond to changes in different process parameters, thereby improving process stability and intelligence.

[0020] The filter is an online self-cleaning filter. Its application eliminates the need for system shutdown to clean filter cake during long-term operation, significantly improving equipment utilization and production efficiency. It also reduces manual maintenance and spare parts wear. Furthermore, it incorporates a modular design. Attached Figure Description

[0021] Figure 1 This is an overall schematic diagram of a double-layer circuit without an intermediate layer and ACF adhesive, provided for an embodiment of this application.

[0022] The markings in the diagram are: 1. Coating head; 2. Material box; 3. Dynamic homogenizing transfer cylinder; 4. Pneumatic pump; 5. Filter; 21. Box body; 22. Discharge pipe; 23. Overflow pipe. Detailed Implementation

[0023] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0024] like Figure 1 As shown, the first embodiment provided in this application is a coating slurry circulation system, the structure of which includes a PLC control system, a coating head 1, a material box 2, a dynamic homogenizing transfer cylinder 3, a pneumatic pump 4, and a filter 5. The PLC control system is electrically connected to the dynamic homogenizing transfer cylinder 3, the coating head 1, the filter 5, and the pneumatic pump 4. The inlet of the coating head 1 is connected to the outlet of the material box 2. The dynamic homogenizing transfer cylinder 3 is located below the material box 2. The inlet of the pneumatic pump 4 is connected to the outlet of the dynamic homogenizing transfer cylinder 3. The outlet of the pneumatic pump 4 is connected to the inlet of the filter 5. The slurry in the material box 2 can also flow into the dynamic homogenizing transfer cylinder 3.

[0025] In actual use, the PLC control system controls the pneumatic pump 4 to start. The slurry in the dynamic homogenizing transfer cylinder 3 enters the filter 5 for filtration under the action of the pneumatic pump 4. After the impurities in the slurry are filtered out by the filter 5, the slurry enters the material box 2. Part of the slurry entering the material box 2 flows into the coating head 1 as coating material, and the other part flows back into the dynamic homogenizing transfer cylinder 3 to complete one cycle. The slurry flowing back from the material box 2 into the dynamic homogenizing transfer cylinder 3 mixes with the original slurry in the dynamic homogenizing transfer cylinder 3 before the next cycle.

[0026] In the above design, the entire coating slurry circulation system can realize the recycling and reuse of excess coating slurry, thereby achieving slurry circulation. This not only reduces the pollution to the working environment during the coating process, but also improves the utilization rate of the slurry to reduce costs. At the same time, through the circulation of the slurry, sedimentation, agglomeration and skinning of the slurry are prevented, ensuring the high uniformity of the slurry components and guaranteeing the coating effect.

[0027] Specifically, the dynamic homogenizing transfer cylinder 3 is further equipped with a temperature control module, which is electrically connected to the PLC system. The temperature control module is used to heat the slurry inside the dynamic homogenizing transfer cylinder 3. The temperature controller module can be a heating rod.

[0028] In actual use, the power of the temperature control module is controlled by the PLC control system, and the temperature control module heats the slurry in the dynamic homogenizing transfer cylinder 3 so that the slurry reaches the temperature required for coating.

[0029] In the above design, the dynamic homogenizing transfer cylinder 3 is equipped with a temperature control module controlled by a PLC control system, which can automatically heat the slurry to ensure that the slurry reaches the required temperature.

[0030] Specifically, the dynamic homogenizing transfer drum 3 is also equipped with a temperature detection module, such as a temperature sensor. The temperature detection module is electrically connected to the PLC control system and is used to detect the temperature of the slurry inside the homogenizing transfer drum.

[0031] In actual use, the temperature of the slurry inside the dynamic homogenizing transfer cylinder 3 is detected by the temperature detection module. The PLC control system controls the operation of the temperature heating module based on the temperature monitored by the temperature detection module, thereby heating or stopping the heating of the slurry.

[0032] In the above design, a temperature detection module electrically connected to the PLC control system is installed in the dynamic homogenizing transfer cylinder 3, which can realize real-time monitoring of the temperature of the slurry in the dynamic homogenizing transfer cylinder 3.

[0033] Specifically: The dynamic homogenizing transfer cylinder 3 is also equipped with a stirring module and an online viscosity sensor. The stirring module includes a mounting frame fixedly installed inside the dynamic homogenizing transfer cylinder 3, a rotating shaft mounted on the mounting frame, several blades mounted at the lower end of the rotating shaft, and a motor mounted on the mounting frame for driving the rotating shaft to rotate. The motor and the online viscosity sensor are both electrically connected to the PLC system.

[0034] In actual use, sedimentation may occur in the dynamic homogenizing transfer drum 3, leading to uneven slurry distribution. An online viscosity sensor monitors the viscosity of the slurry within the dynamic homogenizing transfer drum 3. When the viscosity falls outside the normal range, the PLC control system activates the stirring module. This involves a motor driving a rotating shaft, which in turn rotates the blades to stir the slurry, ensuring thorough and uniform mixing.

[0035] In the above design, the stirring module is designed to stir the slurry in the dynamic homogenizing transfer cylinder 3, so as to achieve uniformity of the slurry and ensure the coating effect.

[0036] Specifically: the motor drives the rotating shaft to rotate, the rotating shaft drives the blades to rotate, and the rotation of the blades stirs the slurry in the dynamic homogenizing rotating drum 3.

[0037] Specifically, the height between the material box 2 and the dynamic homogenizing transfer cylinder 3 is no higher than 1m.

[0038] In the above design, the height difference between the material box 2 and the dynamic homogenizing transfer cylinder 3 facilitates the maintenance of the material box 2.

[0039] Specifically: such as Figure 1 As shown, the material box 2 includes a box body 21, an overflow pipe 23 disposed on one side of the box body 21, and a discharge pipe 22 disposed on the box body 21. The discharge pipe 22 is connected to the coating head 1. The connection point between the overflow pipe 23 and the box body 21 is higher than the connection point between the discharge pipe 22 and the box body 21. The lower end of the overflow pipe 23 is in contact with the inner wall of the dynamic homogenizing transfer cylinder 3.

[0040] In actual use, the slurry filtered by filter 5 flows into the housing 21. Before the slurry level in the housing 21 reaches the connection height between the housing 21 and the overflow pipe 23, the slurry flows into the coating head 1 along the discharge pipe 22. When the slurry exceeds the amount required by the coating head 1, the slurry level will reach the connection between the housing 21 and the overflow pipe 23 and flow along the overflow pipe 23 into the dynamic homogenizing transfer cylinder 3.

[0041] In the above design, the material box 2 has an overflow structure (overflow pipe 23). The overflow structure enables excess slurry to flow back to the dynamic homogenizing transfer cylinder 3 below, thereby realizing the recycling of excess slurry and achieving slurry circulation.

[0042] Specifically: the slurry in the material box 2 first flows along the discharge pipe 22 to the coating head 1, and the excess slurry flows along the return pipe into the dynamic homogenizing transfer cylinder 3.

[0043] Specifically, the overflow pipe 23 is a soft pipe.

[0044] In the above design, the flexible pipe can be laid in any path, which is convenient for installation.

[0045] The second embodiment provided in this application is a coating slurry circulation method, which adopts the coating slurry circulation system and includes the following steps: S1, injecting slurry into the dynamic homogenizing transfer cylinder 3; S2, starting the pneumatic pump 4 so that the slurry in the dynamic homogenizing transfer cylinder 3 enters the filter 5 for filtration, and the slurry after filtration by the filter 5 flows into the material box 2; S3, a portion of the slurry in the material box 2 is supplied to the coating head 1, and the remaining portion is returned to the dynamic homogenizing transfer cylinder 3.

[0046] In the above design, the coating slurry circulation method can realize the return of excess slurry from the material box 2 to the dynamic homogenizing transfer cylinder 3 during coating, thereby improving the utilization rate of slurry and reducing costs.

[0047] The third embodiment of this application provides a coating slurry circulation system, including a PLC control system, a coating head 1, a material box 2, a dynamic homogenizing transfer cylinder 3, a pneumatic pump 4, and a filter 5. The filter 5 is an online self-cleaning filter with a dual-element filter structure. The PLC control system is electrically connected to the dynamic homogenizing transfer cylinder 3, the coating head 1, the filter 5, and the pneumatic pump 4. The inlet of the coating head 1 is connected to the outlet of the material box 2. The dynamic homogenizing transfer cylinder 3 is located below the material box 2. The inlet of the pneumatic pump 4 is connected to the outlet of the dynamic homogenizing transfer cylinder 3, and the outlet of the pneumatic pump 4 is connected to the inlet of the filter 5. The slurry in the material box 2 can also flow into the dynamic homogenizing transfer cylinder 3. A temperature control module is also provided inside the dynamic homogenizing transfer cylinder 3. The temperature control module is electrically connected to the PLC system and is used to heat the slurry inside the homogenizing transfer cylinder. The dynamic homogenizing transfer cylinder 3 is also equipped with a temperature detection module, which is electrically connected to the PLC system. The temperature detection module is used to detect the temperature of the slurry inside the homogenizing transfer cylinder. The dynamic homogenizing transfer cylinder 3 is also equipped with a stirring module and an online viscosity sensor. The stirring module includes a mounting frame fixedly installed inside the dynamic homogenizing transfer cylinder 3, a rotating shaft mounted on the mounting frame, several blades located at the lower end of the rotating shaft, and a motor mounted on the mounting frame to drive the rotating shaft. The motor, the online viscosity sensor, and the density meter are electrically connected to the PLC system. The motor drives the rotating shaft to rotate, which in turn drives the blades to rotate, thus stirring the slurry in the dynamic homogenizing transfer cylinder 3. The height of the material box 2 relative to the dynamic homogenizing transfer cylinder 3 is no more than 1m. The material box 2 includes a box body 21, an overflow pipe 23 disposed on one side of the box body 21, and a discharge pipe 22 disposed on the box body 21. The discharge pipe 22 is connected to the coating head 1. The connection point between the overflow pipe 23 and the box body 21 is higher than the connection point between the discharge pipe 22 and the box body 21. The lower end of the overflow pipe 23 is in contact with the inner wall of the dynamic homogenizing transfer cylinder 3. The slurry in the material box 2 first flows to the coating head 1 along the discharge pipe 22, and excess slurry flows into the dynamic homogenizing transfer cylinder 3 along the return pipe. The overflow pipe 23 is a flexible pipe.

[0048] In actual use, the slurry is first poured into the dynamic homogenizing transfer tank. The PLC control system controls the stirring module to turn on. The stirring module drives the rotating shaft through the motor, which in turn drives the blades to stir the slurry. The temperature control module heats the slurry until the online viscosity sensor detects the viscosity of the slurry and the temperature detection module detects that it is within acceptable limits. Then, the PLC control system controls the start-up pump to start. The pneumatic pump 4 delivers the slurry in the dynamic homogenizing transfer tank 3 to the filter 5 for filtration and then into the material box 2. A portion of the slurry enters the coating head 1 along the discharge pipe 22, and the excess slurry flows back into the dynamic homogenizing transfer tank along the overflow pipe 23. During the slurry delivery process, the PLC sets the output pressure of the pneumatic pump 4 to 2.4 Bar, the stirring speed to 300 rpm, and the temperature of the transfer tank to 25℃. The online viscosity sensor and density meter provide real-time feedback data. If the detected value deviates from 1200 CP or the solid content fluctuates by more than ±2%, the pump speed is automatically adjusted or the slurry is replenished to ensure that the slurry performance remains constant during the coating process. During system operation, the PLC control system records viscosity, density, and temperature data every 30 seconds and generates trend curves for easy traceability and analysis.

[0049] The above design enables automatic circulation of slurry, thereby improving the utilization rate of slurry.

[0050] In further detail, it should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A coating slurry circulation system, characterized in that: The system includes a PLC control system, a coating head (1), a material box (2), a dynamic homogenizing transfer cylinder (3), a pneumatic pump (4), and a filter (5). The PLC control system is electrically connected to the dynamic homogenizing transfer cylinder (3), the coating head (1), the filter (5), and the pneumatic pump (4). The inlet of the coating head (1) is connected to the outlet of the material box (2). The dynamic homogenizing transfer cylinder (3) is located below the material box (2). The inlet of the pneumatic pump (4) is connected to the outlet of the dynamic homogenizing transfer cylinder (3). The outlet of the pneumatic pump (4) is connected to the inlet of the filter (5). The slurry in the material box (2) can also flow into the dynamic homogenizing transfer cylinder (3).

2. The coating slurry circulation system according to claim 1, characterized in that: The dynamic homogenizing transfer cylinder (3) is also equipped with a temperature control module, which is electrically connected to the PLC system. The temperature control module is used to heat the slurry in the dynamic homogenizing transfer cylinder (3).

3. The coating slurry circulation system according to claim 1, characterized in that: The dynamic homogenizing transfer cylinder (3) is also equipped with a temperature detection module, which is electrically connected to the PLC system. The temperature detection module is used to detect the temperature of the slurry inside the dynamic homogenizing transfer cylinder (3).

4. The coating slurry circulation system according to claim 1, characterized in that: The dynamic homogenizing transfer cylinder (3) is also equipped with a stirring module and an online viscosity sensor. The stirring module includes a mounting frame fixedly installed inside the dynamic homogenizing transfer cylinder (3), a rotating shaft mounted on the mounting frame, several blades mounted at the lower end of the rotating shaft, and a motor mounted on the mounting frame for driving the rotating shaft to rotate. The motor, the online viscosity sensor, and the density meter are electrically connected to the PLC system.

5. The coating slurry circulation system according to claim 4, characterized in that: The motor drives the rotating shaft to rotate, the rotating shaft drives the blades to rotate, and the rotation of the blades stirs the slurry in the dynamic homogenizing rotating drum (3).

6. The coating slurry circulation system according to claim 1, characterized in that: The height between the material box (2) and the dynamic homogenizing transfer cylinder (3) is no higher than 1m.

7. The coating slurry circulation system according to claim 1, characterized in that: The material box (2) includes a box body (21), an overflow pipe (23) disposed on one side of the box body (21), and a discharge pipe (22) disposed on the box body (21). The discharge pipe (22) is connected to the coating head (1). The connection between the overflow pipe (23) and the box body (21) is higher than the connection between the discharge pipe (22) and the box body (21). The lower end of the overflow pipe (23) is in contact with the inner wall of the dynamic homogenizing transfer cylinder (3).

8. The coating slurry circulation system according to claim 7, characterized in that: The slurry in the material box (2) first flows along the discharge pipe (22) to the coating head (1), and the excess slurry flows along the return pipe into the dynamic homogenizing transfer cylinder (3).

9. The coating slurry circulation system according to claim 7, characterized in that: The overflow pipe (23) is a soft pipe.

10. A method for circulating coating slurry, employing the coating slurry circulation system described in claims 1 to 9, characterized in that: The process includes the following steps: S1, injecting the slurry into the dynamic homogenizing transfer cylinder (3); S2, starting the pneumatic pump (4) so ​​that the slurry in the dynamic homogenizing transfer cylinder (3) enters the filter (5) for filtration, and the slurry after filtration by the filter (5) flows into the material box (2); S3, a portion of the slurry in the material box (2) is supplied to the coating head (1), and the remaining portion flows back to the dynamic homogenizing transfer cylinder (3).

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