A filtration kettle suction filtration system and automatic control method

Abstract

The application relates to the technical field of filter kettles, in particular to a filter kettle suction filtration system, which comprises a filter kettle, a refrigerant buffer tank, a heater, a product buffer tank, a filtrate buffer tank, a vacuum buffer tank, a vacuum unit, a refrigeration unit and a conveying pump; a bypass is connected in parallel on the pipeline of the heater; refrigerant in the refrigerant buffer tank is sent into the jacket of the filter kettle through the conveying pump, the bypass or the heater; the pipeline of the refrigeration unit sends the heat-exchanged refrigerant back to the refrigerant buffer tank; the product buffer tank and the filtrate buffer tank are respectively connected to the bottom discharge port of the filter kettle; the vacuum unit is connected to the filtrate buffer tank through the vacuum buffer tank. The system does not need to switch different cold and hot media, and the safety is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of filter tank technology, specifically a filter tank suction filtration system and automatic control method. Background Technology

[0002] Currently, the traditional control methods for filtration and temperature control in filter presses involve pump-assisted filtration or gravity flow of the filtrate, using different low-temperature and high-temperature media. The drawbacks are incomplete filtrate removal and the use of different heat transfer media in the same jacket, which can easily lead to mixing. This is especially problematic for equipment requiring ultra-low and high-temperature control. Low-temperature media often include ethylene glycol and calcium chloride, while high-temperature media are typically heat transfer oil, steam, or hot water. During temperature switching, incomplete removal of the heat transfer media from the jacket can lead to mixing of high and low-temperature media, affecting the quality of the heat transfer medium and posing a certain degree of danger. Furthermore, human error during operation can cause mixing of hot and cold media, potentially resulting in quality and safety accidents. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a filtration system and automatic control method for a filtration vessel, which solves the issues of inefficient filtration in existing filtration vessels and the need to switch between different hot and cold media during cooling and heating processes.

[0004] A filtration system includes a filter, a refrigerant buffer tank, a heater, a product buffer tank, a filtrate buffer tank, a vacuum buffer tank, a vacuum unit, a refrigeration unit, and a transfer pump. A bypass is connected in parallel to the heater's pipeline. Refrigerant in the refrigerant buffer tank is delivered to the jacket of the filter via the transfer pump, the bypass, or the heater. The refrigeration unit's pipeline returns the refrigerant after heat exchange to the refrigerant buffer tank. The product buffer tank and the filtrate buffer tank are respectively connected to the bottom discharge port of the filter. The vacuum unit is connected to the filtrate buffer tank via the vacuum buffer tank.

[0005] In the above-mentioned filtration system, a filter is connected in parallel on the pipeline of the refrigeration unit.

[0006] An automatic control method for a filtration system as described above includes the following steps: (a) Low temperature mode: The refrigeration unit is turned on, and the refrigerant in the refrigerant buffer tank is reduced to the set temperature of -35℃. The transfer pump is started to transfer the refrigerant from the bypass to the jacket of the filter. The refrigerant after heat exchange is returned to the refrigerant buffer tank through the refrigeration unit. The branch of the refrigeration unit connected in parallel with the filter is also in the start state to establish a cold cycle. The mixed crystallization liquid and solvent are introduced into the filter. The filter is started to stir. The exhaust gas is discharged through the filter and the exhaust gas temperature is controlled at -30~-25℃. Stirring is stopped after the temperature in the filter is -30~-25℃. The material in the filter is frozen and crystallized for 1 hour. (II) Vacuum Filtration: After the material in the filter kettle has crystallized, close the switch valve between it and the filter, start the vacuum unit, and after the pressure reaches the set -99.5KPa, open the switch valve at the bottom of the filter kettle and between it and the product buffer tank and the filtrate buffer tank to perform negative pressure filtration. The filtrate enters the filtrate buffer tank for temporary storage. When no liquid falls, close the switch valve at the bottom of the filter kettle and between it and the filtrate buffer tank, and stop the vacuum unit. The filtrate in the filter kettle has completed vacuum filtration. (III) High temperature mode: The heat source enters the heater to preheat to 80°C, establishes a heat cycle, and gradually opens the switch valve on the main heating line and closes the switch valve on the refrigeration pipeline of the refrigeration unit. When the refrigerant outlet of the heater reaches the set temperature of 80°C, the refrigerant melts the crystallized material in the filter kettle at high temperature. After running for 2 hours, the switch valve at the bottom of the filter kettle and between it and the product buffer tank is opened, and the melted product enters the product buffer tank for storage.

[0007] The beneficial effects of this invention are as follows: This patent uses a vacuum unit with negative pressure to effectively remove the filtrate from the crystallizing material. Based on the required cooling and crystallization operating temperature of the filter kettle, a refrigeration unit cools the refrigerant, which is then transported via a refrigerant buffer tank pump to the jacket of the multiple filter kettles for cooling. The refrigerant returns to the refrigeration unit's cooling cycle. After crystallization is complete in the filter kettle, a vacuum system is used to perform negative pressure filtration of the medium inside the filter kettle. The filtrate enters the filtrate buffer tank, and the crystallized material is placed on the filter bed. When the filter kettle needs to be heated and melted, the valves connecting the filter kettle jacket to the refrigeration unit and the refrigeration unit to the refrigerant buffer tank are closed. The valves connecting the filter kettle jacket to the refrigerant buffer tank and the heat exchanger heat source regulating valve are opened. By controlling the refrigerant temperature at the heat exchanger outlet and adjusting the opening of the heat source regulating valve, the refrigerant is heated, thus achieving temperature control of the filter kettle. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the system structure according to an embodiment of the present invention.

[0009] Attached reference numerals: 1-Filter vessel; 2-Refrigerant buffer tank; 3-Heater; 4-Product buffer tank; 5-Filtrate buffer tank; 6-Vacuum buffer tank; 7-Vacuum unit; 8-Filter; 9-Refrigeration unit; 10-Transfer pump; 11-Bypass.

[0010] The diagram also includes TE for temperature sensor, PT for pressure gauge, FI for flow meter, square heads for on / off valves, semi-circular heads for regulating valves, solid lines for connecting pipes, and dashed lines for control lines. Detailed Implementation

[0011] The technical solution of the present invention will now be described in detail with reference to the accompanying drawings. The following embodiments are illustrative; unless otherwise specifically stated, the relative arrangement and numerical expressions of components and steps described in these embodiments should not be construed as limiting the scope of this application. The following description of exemplary embodiments is merely illustrative and is not intended to limit the scope of this application or its application or use in any way. Techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail here, but where applicable, such techniques, methods, and apparatus should be considered part of this specification.

[0012] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. When the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof. Unless otherwise stated, the terms "installed," "connected," "linked," etc., in this application should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to an internal connection between two elements or an interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0013] For ease of description, the use of terms such as "upper," "lower," "left," "right," "bottom," and "top" in this application does not limit the structure. It is merely for the purpose of understanding the structural principles of this application in conjunction with the accompanying drawings, and does not indicate or imply that the equipment or components referred to must have a specific orientation, or be constructed and operated in a specific orientation. It should not be construed as a limitation of this application.

[0014] This embodiment is a filtration system for a filter vessel, including a filter vessel 1, a refrigerant buffer tank 2, a heater 3, a product buffer tank 4, a filtrate buffer tank 5, a vacuum buffer tank 6, a vacuum unit 7, a refrigeration unit 9, and a transfer pump 10. A bypass 11 is connected in parallel to the pipeline of the heater 3. The refrigerant in the refrigerant buffer tank 2 is sent to the jacket of the filter vessel 1 via the transfer pump 10, the bypass 11, or the heater 3. The pipeline of the refrigeration unit 9 sends the refrigerant after heat exchange back to the refrigerant buffer tank 2. The product buffer tank 4 and the filtrate buffer tank 5 are respectively connected to the bottom discharge port of the filter vessel 1. The vacuum unit 7 is connected to the filtrate buffer tank 5 via the vacuum buffer tank 6.

[0015] Furthermore, a filter 8 is connected in parallel to the pipeline of the refrigeration unit 9, and the filter port of the filter 8 is connected to the top of the filter vessel 1. A low-temperature refrigerant is used to cool the exhaust gas inside the filter 8 to facilitate subsequent absorption. Figure 1 As shown, a temperature sensor is installed on the exhaust gas absorption pipeline of filter 8, and a control feedback is provided on the discharge regulating valve on the low-temperature refrigerant outlet pipeline, which facilitates adaptive adjustment of the refrigerant flow rate according to the exhaust gas temperature.

[0016] This application uses LM-8GL type Ice River refrigerant, which has a wider temperature range of -50~100℃, is non-volatile, has no flash point, is non-flammable, and has low toxicity. External heating and cooling are used to effectively prevent the mixing of different media. Even in the event of human error, no safety accidents will occur. Furthermore, the increased automation and sequential control procedures significantly reduce human intervention and achieve the goal of reducing personnel and optimizing hazardous chemical processes. System startup state: Equipment 1 to 10 are all in a stopped state, valves are all closed, and instruments are in normal operating condition. The automatic control process and principle of this system are as follows, with each step executed automatically: Low-temperature mode: Refrigeration unit 9 is turned on, lowering the refrigerant in refrigerant buffer tank 2 to the set temperature of -35℃. The transfer pump 10 is started to deliver the refrigerant from bypass 11 to the jacket of filter vessel 1. The refrigerant after heat exchange returns to the refrigerant buffer tank 2 via the refrigeration unit. The branch of refrigeration unit 9 connected in parallel with filter 8 is also in the starting state, thus establishing a cold cycle for filter vessel 1. Mixed crystallizing liquid and solvent are introduced into filter vessel 1, with the feed temperature controlled at -30~-25℃. Filter vessel 1 is stirred, and the exhaust gas is discharged through filter 8 with the exhaust gas temperature controlled at -30~-25℃. Stirring is stopped after the temperature in filter vessel 1 reaches -30~-25℃, and the material in filter vessel 1 is frozen and crystallized for 1 hour.

[0017] Second, vacuum filtration: After the material in filter vessel 1 has crystallized, close the switch valve between it and filter 8, start vacuum unit 7, and after the pressure reaches the set -99.5KPa, open the switch valve at the bottom of filter vessel 1 and between it and product buffer tank 4 and filtrate buffer tank 5 to perform negative pressure filtration. The filtrate enters filtrate buffer tank 5 for temporary storage. When no liquid falls, filtrate buffer tank 5 is equipped with a sight glass. Close the switch valve at the bottom of filter vessel 1 and between it and filtrate buffer tank 5, and stop vacuum unit 7. The filtrate in filter vessel 1 has completed vacuum filtration.

[0018] Three high-temperature modes: The heat source enters the heater 3 to preheat to 80°C, establishes a thermal cycle, and gradually opens the switch valve on the main heating line and closes the switch valve on the refrigeration pipeline of the refrigeration unit 9. When the refrigerant outlet of the heater 3 reaches the set temperature of 80°C and the material melting temperature is greater than or equal to 60°C, the refrigerant melts the crystallized material in the filter kettle 1 at high temperature. After running for 2 hours, the switch valve at the bottom of the filter kettle 1 and between it and the product buffer tank 4 is opened, and the molten product enters the product buffer tank 4 for storage.

[0019] The above are merely preferred embodiments of this application. It should be noted that, for those skilled in the art, several structural changes or improvements can be made without departing from the principles of this application, and these changes or improvements should also be considered within the scope of protection of this application.

Claims

1. A filtration system for a filter vessel, characterized in that: The system includes a filter tank (1), a refrigerant buffer tank (2), a heater (3), a product buffer tank (4), a filtrate buffer tank (5), a vacuum buffer tank (6), a vacuum unit (7), a refrigeration unit (9), and a transfer pump (10). A bypass (11) is connected in parallel to the pipeline of the heater (3). The refrigerant in the refrigerant buffer tank (2) is sent to the jacket of the filter tank (1) via the transfer pump (10), the bypass (11), or the heater (3). The pipeline of the refrigeration unit (9) sends the refrigerant after heat exchange back to the refrigerant buffer tank (2). The product buffer tank (4) and the filtrate buffer tank (5) are respectively connected to the bottom discharge port of the filter tank (1). The vacuum unit (7) is connected to the filtrate buffer tank (5) via the vacuum buffer tank (6).

2. The filtration system according to claim 1, characterized in that: A filter (8) is connected in parallel on the pipeline of the refrigeration unit (9).

3. An automatic control method for a filtration system as described in claim 1 or 2, characterized in that, Includes the following steps: (a) Low temperature mode: The refrigeration unit (9) is turned on, and the refrigerant in the refrigerant buffer tank (2) is reduced to the set temperature of -35℃. The transfer pump (10) is started to transfer the refrigerant from the bypass (11) to the jacket of the filter (1). The refrigerant after heat exchange is returned to the refrigerant buffer tank (2) through the refrigeration unit. The branch of the refrigeration unit (9) connected in parallel with the filter (8) is also in the start state, and a cold cycle is established. Mixed crystallizing liquid and solvent are introduced into the filter (1). The filter (1) is started to stir. The tail gas is discharged through the filter (8) and the tail gas temperature is controlled at -30~-25℃. After the temperature in the filter (1) is -30~-25℃, the stirring is stopped. The material in the filter (1) is frozen and crystallized for 1 hour. (ii) Vacuum filtration: After the material in the filter vessel (1) has crystallized, close the switch valve between it and the filter (8), start the vacuum unit (7), and after the pressure reaches the set -99.5KPa, open the switch valve at the bottom of the filter vessel (1) and between it and the product buffer tank (4) and the filtrate buffer tank (5) to perform negative pressure filtration. The filtrate enters the filtrate buffer tank (8) for temporary storage. When there is no liquid falling, close the switch valve at the bottom of the filter vessel (1) and between it and the filtrate buffer tank (5), and stop the vacuum unit (7). The filtrate in the filter vessel (1) has completed vacuum filtration. (III) High temperature mode: The heat source enters the heater (3) to preheat to 80°C, establishes a heat cycle, gradually opens the switch valve on the main heating line and closes the switch valve on the refrigeration pipeline of the refrigeration unit (9). When the refrigerant outlet of the heater (3) reaches the set temperature of 80°C, the refrigerant melts the crystal material in the filter kettle (1) at high temperature. After running for 2 hours, the switch valve at the bottom of the filter kettle (1) and between it and the product buffer tank (4) is opened, and the melted product enters the product buffer tank (4) for storage.

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