Multifunctional centrifugal plate filter press solid-liquid separation device and separation method of polysulfone product

Abstract

The application discloses a kind of polysulfone product multifunctional centrifugal plate filter-pressing solid-liquid separation device and separation method, including high-pressure pump, container body, rotor being arranged in container body and plate filter-pressing mechanism being arranged in rotor, the high-pressure pump is communicated with container body by feed inlet, the bottom of the container body is also provided with clear liquid outlet, the plate filter-pressing mechanism is provided with filter-pressing outlet, the rotor is rotatable drum with filter hole being arranged in bottom and side wall, scraper is also arranged in the container body, and the scraper is close to the inner wall of rotor.The application solves the problem that solid and liquid are difficult to separate in the existing production process, realizes heat preservation to ensure the reduction of material viscosity, based on the centrifugal mode, the solid-liquid separation is quickly carried out, and then the filtrate is filtered by plate type circulation to reach the required discharge filter equipment, and hot solvent is added to bubble wash the solid to extract the product in the original liquid, to ensure the yield of product.

Description

Technical Field

[0001] This invention belongs to the field of chemical production equipment technology, specifically relating to a multifunctional solid-liquid separation device suitable for high-viscosity, ultrafine powders. Background Technology

[0002] Polysulfone, polyethersulfone, and polyphenylsulfone are high molecular weight polymers, which are amorphous thermoplastic resins. Their characteristics include excellent mechanical properties, high rigidity, wear resistance, and high strength. Due to these favorable properties, polysulfone has been widely used in high-end fields such as film-grade materials, medical devices, aerospace, and electronics.

[0003] Currently, the most advanced production process for polysulfone polymer materials is a one-step synthesis method. After the polymerization reaction is complete, a low-water solvent, the same as the polymerization solvent, is added to the polymerization reactor to lower the reaction temperature, terminate the polymerization reaction, and reduce the viscosity of the polymer solution. At this point, the diluted polymerization solution still has a high viscosity, and the temperature needs to be maintained between 100-140℃. Then, the diluted solution is piped through the bottom of the reactor into a solid-liquid separation device to filter out reaction byproducts, unreacted salt-forming agents, and mechanical impurities.

[0004] However, at this time, the viscosity of the polymer solution changes greatly as the temperature decreases, so heat preservation or heating is required during solid-liquid separation. The polymer solution system contains ultrafine powder, has a slow sedimentation rate, and requires a continuous, closed, nitrogen-protected, and solid washing process.

[0005] Currently, traditional solid-liquid separation equipment mainly includes: centrifugal filtration, vacuum filtration, pressure filtration, plate filtration, plate and frame filtration, and three-in-one machines. Centrifugal filtration is the fastest method for solid-liquid separation. Centrifugation methods include horizontal sedimentation centrifuges, which are suitable for materials with high solid content, low viscosity, and fast solid settling. Furthermore, the material temperature cannot exceed 90℃, and the filter residue has excessive moisture content, making the material unsuitable for horizontal sedimentation centrifuges. Ultrafine powders easily clog the filter screens of horizontal and plate centrifuges, and solid washing does not meet the requirements. Vacuum filtration and pressure filtration both suffer from ultrafine powder clogging of the filter screens. Plate filtration requires repeated filtration, has a slow filtration rate, and leaves residual liquid containing solids, failing to achieve complete solid-liquid separation. Plate and frame filtration has a large filtration area, making heat preservation and heating difficult to implement. Three-in-one solid-liquid separation equipment uses pressure or vacuum during the filtration process, but ultrafine powders easily clog the filter screens, failing to meet the process requirements. Therefore, it is necessary to develop a multifunctional solid-liquid separation device suitable for high viscosity, ultrafine powders, and high heat preservation. Summary of the Invention

[0006] To address the problems existing in the prior art, the present invention provides a multifunctional centrifugal plate filter press solid-liquid separation device for polysulfone products.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a method for solid-liquid separation of polysulfone products using a solid-liquid separation device, comprising the following steps:

[0008] Step S1: The viscous polysulfone product is fed into the container through the feed port and centrifuged under the centrifugal action of the rotor. The filtrate enters the container through the filter holes on the side wall and bottom of the rotor, and the filter residue forms a filter layer on the inner wall of the rotor.

[0009] Step S2: Continue centrifugation until the filtrate output from the container drops below 50% of the initial output. Stop centrifugation and close the outlet. Then, start the high-pressure pump to pressurize the container. The viscous polysulfone product flows out from the outlet after passing through the plate filter press in the container.

[0010] Step S3: When the container is full of liquid, turn on the circulation pump to send the collected filtrate back to the container for circulation until the filtrate collected from the outlet becomes clear.

[0011] Step S4: Next, start the siphon control so that the filtered clear liquid in the container enters the centrifugal rotor through the siphon for further filtration and is discharged from the outlet.

[0012] Step S5: Finally, open the bottom cover of the container, scrape off the filter layer inside the rotor with a scraper, and remove the filter residue from the surface of the plate filter press.

[0013] This invention also provides a multifunctional centrifugal plate filter press solid-liquid separation device for polysulfone products, comprising a high-pressure pump, a container body, a rotor disposed within the container body, and a plate filter press mechanism disposed within the rotor.

[0014] The high-pressure pump is connected to the container body through the feed inlet. The bottom of the container body is also provided with a clear liquid outlet. The plate filter press mechanism is provided with a filter outlet. The rotor is a rotatable drum with filter holes on the bottom and side walls. The container body is also provided with a scraper, which is close to the inner wall of the rotor.

[0015] Preferably, the system also includes a circulation pump connected to the filter outlet, which is connected to the feed inlet via a pipeline pump. During the final stage of filtration, the circulation pump circulates the filtrate throughout the separation equipment through the filter discs until the solids completely form a stable filter layer on the filter discs. This allows for 100% treatment of the filtrate with no residue, thereby improving product yield.

[0016] Preferably, a siphon tube is provided between the rotor and the container body. The scraper has a hollow structure and is fitted with a siphon tube, the other end of which is connected to the container body. After filtration is completed, the siphon control is turned on, allowing the filtered liquid in the rotor to be discharged from the filtration outlet via siphon.

[0017] Preferably, the bottom cross-section of the rotor is W-shaped.

[0018] Preferably, the plate filter press mechanism includes a rotating shaft and a multi-layer filter plate disposed on the rotating shaft. The rotating shaft and the multi-layer filter plate are hollow inside, and the filter plate is provided with filter holes. The filter plate is connected to the filter outlet after communicating with the rotating shaft.

[0019] The present invention also provides a method for solid-liquid separation of polysulfone products based on the above-mentioned solid-liquid separation device, comprising the following steps:

[0020] Step S1: The viscous polysulfone product is fed into the rotor of the container through the feed port and centrifuged under the centrifugal action of the rotor rotation. The filtrate enters the container through the filter holes on the side wall and bottom of the rotor, and the filter residue forms a filter layer on the inner wall of the rotor.

[0021] Step S2: Continue centrifugation until the amount of clear liquid discharged from the outlet drops below 50% of the initial amount. Stop the rotor rotation and close the clear liquid outlet. Then start the high-pressure pump for pressure filtration. The filtrate flows out from the pressure outlet after passing through the plate filter press mechanism.

[0022] Step S3: When the container is full of liquid, turn on the circulation pump to send the collected filtrate back to the container for circulation until the filtrate collected from the clear liquid outlet and the pressure filter outlet becomes clear.

[0023] Step S4: Start the siphon control so that the filtered clear liquid in the rotating drum enters the rotor through the siphon and is discharged from the filter outlet.

[0024] Step S5: Finally, open the bottom cover of the container, scrape off the filter layer inside the rotor with a scraper, and remove the filter residue from the surface of the plate filter press.

[0025] Beneficial effects: Compared with existing technologies, this invention solves the problem of solid-liquid separation in existing production processes. The combination of multiple filtration methods meets production quality requirements. The filtration equipment can be insulated and heated to ensure a reduction in material viscosity. Centrifugation is selected first as the fastest method for solid-liquid separation, allowing for rapid solid-liquid separation of large quantities of material. Then, the material undergoes plate-type circulating filtration until the filtrate reaches the required level and is discharged from the filtration equipment. Simultaneously, hot solvent is added to wash the solids and extract the product from the original liquid, ensuring product yield. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Wherein:

[0027] Figure 1 This is a schematic diagram of the multifunctional centrifugal plate filter press solid-liquid separation device for polysulfone products described in this invention.

[0028] The components include: 1. High-pressure pump; 2. Container body; 3. Rotor; 4. Feed inlet; 5. Rotating shaft; 6. Filter plate; 7. Scraper; 8. Siphon tube; 9. Clear liquid outlet; 10. Filter press outlet; and 11. Circulation pump. Implementation

[0029] The present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. After reading this invention, any modifications of the invention in various equivalent forms by those skilled in the art fall within the scope defined by the appended claims.

[0030] Traditional, standalone solid-liquid separation equipment is insufficient for this production process. For ultrafine polysulfone powder, the selection of filter screens is too difficult. If the mesh size is too high, the ultrafine powder affects the filtration speed and easily clogs the filter, making continuous filtration difficult and reducing production efficiency. If the mesh size is too low, complete solid-liquid separation cannot be achieved. Traditional separation equipment can only provide external insulation, which is easily affected by temperature-sensitive materials, hindering solid-liquid separation and reducing production efficiency.

[0031] like Figure 1 As shown, the multifunctional centrifugal plate filter press solid-liquid separation device for polysulfone products of the present invention mainly includes a high-pressure pump, a circulating pump, a scraper, a container body, a rotor disposed within the container body, and a plate filter press mechanism disposed within the rotor. The rotor is a rotatable drum with filter holes on its bottom and side walls, and the bottom of the drum is designed in a W shape. The bottom and top of the container body are respectively provided with a clear liquid outlet and a feed inlet. The high-pressure pump is connected to the container body through the feed inlet.

[0032] The plate filter press mechanism includes a rotating shaft and a multi-layer filter plate mounted on the rotating shaft. Both the rotating shaft and the multi-layer filter plate have hollow interiors. The rotating shaft is hollow and serves as a collecting pipe that communicates with the hollow interior of the circular multi-layer filter plate. The filter plate has filter holes that allow filtered water to pass through and then be discharged through the rotating shaft. A filter outlet is provided at the bottom of the rotating shaft. The scraper is located near the inner wall of the rotor.

[0033] The device of this invention is a top-suspended type, with a rotating shaft driving the rotor to rotate, thereby realizing centrifugal solid-liquid separation; the filter disc is connected to the rotating shaft and is hollow, and the filtrate passes through the hollow pipe to the filter outlet; the filter disc can be selectively used as a disc-type resistance heating device, and the number of heating discs is selected according to the material properties and the size of the equipment.

[0034] In conventional pressure filtration, during the final stage of separation, when the filtrate just fills the entire space of the equipment and the filtrate level is below the highest filter plate, there will be a shortcut, and pressure filtration will not be able to proceed. This invention incorporates a filtrate circulation system. In the final stage of separation, the pressure filtration circulation system is turned on until the solids form a stable filter layer on the surface of the filter plate and the filtrate becomes clear, and then it is drained through the bottom outlet.

[0035] After solid-liquid separation, the equipment is filled with the corresponding solvent (which can be heated) and directed towards the filter layer; after the filter layer is cleaned, the bottom closed cover is opened, the filter layer formed inside the rotor is discharged by a scraper, and the filter residue on the filter plate is discharged by centrifugation.

[0036] The polysulfone product of this invention is based on a solid-liquid separation method using the aforementioned solid-liquid separation device, specifically comprising the following steps:

[0037] First, the viscous polysulfone product is fed into the rotor of the container through the feed port, and centrifugation is carried out under the centrifugal action of the rotor rotation. The filtrate enters the container through the filter holes on the side wall and bottom of the rotor, and the filter residue forms a filter layer on the inner wall of the rotor.

[0038] Then, continue centrifugation until the amount of clear liquid discharged from the outlet drops to less than 50% of the initial amount. Stop the rotor rotation and close the clear liquid outlet. Then start the high-pressure pump for pressure filtration. The filtrate flows out from the pressure outlet after passing through the plate filter press mechanism.

[0039] Next, when the container is full of liquid, turn on the circulation pump to send the collected filtrate back into the container for circulation until the filtrate collected from the clear liquid outlet and the pressure filter outlet becomes clear.

[0040] Continue to start the siphon control so that the filtered clear liquid in the drum enters the rotor through the siphon and is discharged from the filter outlet;

[0041] Finally, slag discharge: Open the bottom closed cover, the filter layer formed inside the rotor is discharged by scraper, and the filter residue on the filter plate is discharged by centrifugation.

Claims

1. A method for solid-liquid separation of polysulfone products using a solid-liquid separation device, characterized in that... Includes the following steps: Step S1: The viscous polysulfone product is fed into the container through the feed port and centrifuged under the centrifugal action of the rotor. The filtrate enters the container through the filter holes on the side wall and bottom of the rotor, and the filter residue forms a filter layer on the inner wall of the rotor. Step S2: Continue centrifugation until the filtrate output from the container drops below 50% of the initial output. Stop centrifugation and close the outlet. Then, start the high-pressure pump to pressurize the container. The viscous polysulfone product flows out from the outlet after passing through the plate filter press in the container. Step S3: When the container is full of liquid, turn on the circulation pump to send the collected filtrate back to the container for circulation until the filtrate collected from the outlet becomes clear. Step S4: Next, start the siphon control so that the filtered clear liquid in the container enters the centrifugal rotor through the siphon for further filtration and is discharged from the outlet. Step S5: Finally, open the bottom cover of the container, scrape off the filter layer inside the rotor with a scraper, and remove the filter residue from the surface of the plate filter press.

2. The method for solid-liquid separation of polysulfone products using the solid-liquid separation apparatus according to claim 1, characterized in that: The solid-liquid separation device includes a high-pressure pump, a container body, a rotor disposed within the container body, and a plate filter press mechanism disposed within the rotor. The high-pressure pump is connected to the container body through the feed inlet. The bottom of the container body is also provided with a clear liquid outlet. The plate filter press mechanism is provided with a filter outlet. The rotor is a rotatable drum with filter holes on the bottom and side walls. The container body is also provided with a scraper, which is close to the inner wall of the rotor.

3. The method for solid-liquid separation of polysulfone products using the solid-liquid separation apparatus according to claim 2, characterized in that: It also includes a circulation pump connected to the filter outlet, which is connected to the feed inlet via a pipeline pump.

4. The solid-liquid separation method for polysulfone products according to the solid-liquid separation device of claim 2, characterized in that: A siphon tube is provided between the rotor and the container body.

5. The solid-liquid separation method for polysulfone products according to the solid-liquid separation device of claim 2, characterized in that: The plate filter press mechanism includes a rotating shaft and multiple filter plates mounted on the rotating shaft. The rotating shaft and the multiple filter plates are hollow inside, and the filter plates are provided with filter holes. The filter plates are connected to the filter outlet after being connected to the rotating shaft.

6. The solid-liquid separation method for polysulfone products according to the solid-liquid separation apparatus of claim 2, characterized in that: The rotor has a W-shaped bottom cross-section.

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