Continuous vacuum filtration membrane preparation method and device

Abstract

The invention belongs to the field of separation membrane preparation, and provides a continuous vacuum filtration membrane preparation method and device, and the device comprises a porous drum, a filtrate tank, a rotary joint, a drum driving device, a membrane collection roller, a roller driving device, a transmission roller, a drying box body, a bearing table and a carrier plate. The porous rotary drum is connected with the filtrate tank, the rotary joint and the rotary drum driving equipment, a basement membrane on the membrane collection rotary roller passes through the transmission roller and then reaches the porous rotary drum, synchronous dynamic real-time rotary drum and vacuum suction filtration are performed under the driving of the rotary drum driving equipment, and a composite membrane layer after suction filtration enters the drying box body through the transmission roller for heat treatment. And finally, winding and collecting on a film collecting roller. And the rotating speed of the porous rotating drum can be adjusted by controlling the rotating drum driving equipment, so that the membrane layer loading time of vacuum filtration and the membrane layer thickness of suction filtration are controlled, and the precise control on the membrane production process is realized. The membrane preparation process is easy to control, operation is simple, the membrane preparation quality is good, automatic control can be achieved, continuous, dynamic, large-scale and batch suction filtration membrane preparation can be achieved, the efficiency and scale of vacuum suction filtration membrane preparation can be effectively improved, and the quality consistency of membrane finished products can be guaranteed.

Description

Technical Field

[0001] The invention belongs to the field of separation membrane preparation and relates to a continuous vacuum filtration membrane making method and device. Background Art

[0002] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention, and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] Membrane separation technology is one of the most promising high-tech technologies in the 21st century. It has the advantages of high efficiency, simple operation, and easy scalability. It is widely used in various fields, such as chemical production, food fermentation, life medicine, water treatment, etc., and has huge development potential. Traditional separation membranes face the trade-off contradiction between permeability and selectivity, which forces people to continuously develop new separation membranes and membrane separation technologies. With the development of nanotechnology, separation membranes prepared using nanomaterials can show performance far higher than traditional separation membranes, and have become a current research hotspot. Among the methods for preparing separation membranes using nanomaterials, vacuum filtration (vacuum assisted filtration) is a membrane preparation method with good film formation, easy control, simple operation, and wide application. It can enable nanomaterials to self-assemble on the surface of the base membrane through vacuum assistance to form a functional membrane layer. This method is widely used in one-dimensional nanomaterial separation membranes such as carbon nanotubes and nanofibers, as well as graphene, MXene, and MoS 2 , C 3 N 4 , COF and other two-dimensional material separation membranes or the preparation of their composite material separation membranes, is an important membrane preparation method (technology). The current vacuum filtration membrane making method is mostly used for the preparation of separation membranes in the laboratory, the filter membrane is fixed on the sand core between the filter cup and the filter bottle, and the preparation of the nano film layer is realized by vacuum filtration. As patents CN204601741U, CN117715695A, CN219209113U, CN215916682U, CN105879685A, CN203108758U, etc., an independent monolithic membrane is placed on a vacuum filtration device for filtration preparation. However, this method also has certain limitations, each vacuum filtration process can only realize the preparation of an independent separation membrane, and it is difficult to realize continuous and large-scale membrane preparation, which makes it limited in terms of device amplification and large-area membrane preparation.

[0004] Patent CN106861448A discloses a method for preparing a highly hydrophilic ultrafiltration membrane of ethylene vinyl alcohol copolymer, using a non-woven fabric as a base membrane, scraping a casting liquid on it, and preparing a highly hydrophilic ultrafiltration membrane through complete gelation I-rolling-complete gelation II. The method of coating the casting liquid + gelation treatment is a phase inversion membrane method, that is, the casting liquid scraped on the base membrane enters the gel bath for phase inversion (i.e. gelation), and continuously prepares an organic polymer membrane. Although this method can be used for continuous membrane formation, it is different from the vacuum filtration membrane method in terms of film formation principle (phase inversion principle vs. vacuum self-assembly principle), device structure (no vacuum device vs. vacuum device required), and membrane process (casting liquid scraping + gelation vs. material dispersion + filtration), and this method cannot be used for vacuum filtration membrane formation.

[0005] Patent CN113788476A discloses a system and method for preparing a graphene film, in which a suction filtration substrate film passes through the filtrate container port and the suction port of the suction filtration device and moves continuously, and under the action of the suction filtration device, the graphene in the graphene solution is covered on the surface of the suction filtration substrate to form a graphene film. In this method, the substrate film moves independently relative to the suction port, and the vacuum filtration process requires the substrate film to fit closely to the suction port to ensure the vacuum negative pressure. It can be seen that this method is difficult to take into account the efficient vacuum filtration process and the continuous movement process of the substrate film, and still needs to be optimized and improved. Therefore, it is still a major challenge to ensure that the substrate film is close to the suction port and can move continuously to achieve continuous vacuum filtration film making.

[0006] In view of this, in the field of separation membrane preparation technology, there is still a need to develop a method for preparing nanomaterial separation membranes by vacuum filtration that is simple to operate, continuous, and large-scale. Summary of the invention

[0007] In order to solve the above problems, the present invention provides a continuous vacuum filtration membrane preparation method and device. The continuous vacuum filtration membrane preparation method adopts a continuous rotary drum vacuum filtration membrane preparation method, and the device is to attach the basement membrane to the surface of a porous rotary drum and place it in a dispersion of nano-membrane raw materials, and through vacuum filtration and dynamic real-time rotary drum, and with subsequent heating treatment steps, continuous, dynamic, and scalable membrane preparation is achieved. The method can effectively improve the efficiency and scale of vacuum filtration method for preparing separation membranes and ensure the consistency of the quality of the finished membrane products.

[0008] In order to achieve the above object, the present invention adopts the following technical solution:

[0009] The first aspect of the present invention provides a continuous vacuum filtration membrane-making device, comprising: a first membrane collection roller 5, a first transmission roller 7, a porous drum 1, a second transmission roller 8, a third transmission roller 9, a drying device 10, a fourth transmission roller 13, and a second membrane collection roller 14 are sequentially arranged along the membrane transmission direction;

[0010] The porous drum 1 is partially immersed in the filtrate tank 2, the interior of the porous drum 1 is connected to a vacuum pump, and the porous drum 1 is in sliding contact with a first transmission roller 7;

[0011] The first film collecting roller 5 and the first transmission roller 7 are connected through a film, and a carrier plate 12 is arranged in the drying device 10; the porous drum 1, the second transmission roller 8, the third transmission roller 9, the carrier plate 12, the fourth transmission roller 13 and the second film collecting roller 14 are connected through a film.

[0012] In some embodiments, a rotating joint 3 is provided at the rotation center position on one side of the porous drum 1, and the rotating joint 3 is connected to the water storage tank and the vacuum filtration pump in sequence, and the rotation center position on the other side of the porous drum 1 is connected to the drum driving device 4.

[0013] In some embodiments, the portion of the porous drum 1 that is tightly attached to the basement membrane is immersed in the filtrate, and the top portion that is not attached to the basement membrane is higher than the surface of the filtrate.

[0014] In some embodiments, the surface pore size of the porous drum 1 is 0.1 to 120 μm;

[0015] In some embodiments, a layer of filter paper or a filter membrane with micron-sized pores is attached to the surface of the porous drum 1 .

[0016] In some embodiments, the rotation speed of the drum driving device 4 is 0 to 10 r / min;

[0017] In some embodiments, the first transmission roller 7 is located above or diagonally above the porous drum 1 .

[0018] In some embodiments, the base membrane is an organic microfiltration, ultrafiltration, or nanofiltration membrane base, the membrane pore size is smaller than the pore size of the porous drum 1, and when the base membrane is attached to the surface of the porous drum 1, it can cover the pores on the surface of the porous drum 1 over a width range.

[0019] In some embodiments, the heat treatment temperature of the drying device 10 is 20-150°C.

[0020] In some embodiments, the widths of the porous drum 1, the first transmission roller 7, the second transmission roller 8, the third transmission roller 9, and the fourth transmission roller 13 are greater than the width of the basement membrane used;

[0021] In some embodiments, the widths of the porous drum 1, the first transmission roller 7, the second transmission roller 8, the third transmission roller 9, and the fourth transmission roller 13 are 250-1200 mm.

[0022] In some embodiments, the filtrate level in the filtrate tank 2 is kept constant.

[0023] The second aspect of the present invention provides a continuous vacuum filtration membrane-making method using the above-mentioned device, comprising:

[0024] The base film is placed on the first film collecting roller 5. Under the drive of the first roller driving device 6, the base film passes through the first transmission roller 7 and then is wound around the porous drum 1. The inside of the porous drum 1 is vacuumed to make the base film close to the porous drum 1.

[0025] The porous drum is driven to rotate by the drum driving device 4, so that the basement membrane is immersed in the filtrate in the filtrate tank 2, and the dynamic real-time drum and vacuum filtration are synchronized. The rotation speed of the porous drum is adjusted by controlling the drum driving device 4, thereby controlling the membrane load time of the vacuum filtration and the membrane thickness of the filtration;

[0026] The filtered membrane layer passes through the second transmission roller 8 and the third transmission roller 9 together with the base membrane, enters the drying box 10 for heat treatment, passes through the rotatable carrier plate 12 in the drying box, and then passes through the fourth transmission roller 13, arrives at the second membrane collection roller 14, and is wound and collected under the drive of the second roller driving device 15.

[0027] Beneficial effects of the present invention

[0028] (1) A continuous vacuum filtration membrane-making method and device involved in the present invention is to attach the basement membrane to the surface of a porous drum by vacuum filtration to perform filtration membrane-making. Driven by the drum driving device, continuous vacuum filtration membrane-making can be achieved, thereby improving production efficiency and equipment utilization rate. The porous drum involved in the method and device needs to accurately control its pore size so that after the pores are infiltrated and filled with liquid, the surface tension of the liquid in the pores is greater than the pressure of vacuum filtration; and the rotation speed of the porous drum can be adjusted by controlling the drum driving device, thereby controlling the membrane load time of vacuum filtration and the membrane thickness of filtration, thereby achieving precise control of the membrane production process. The membrane-making process of the method and device described in the present invention is easy to control, simple to operate, and has good membrane quality. It can automatically control and realize large-scale, batch filtration membrane-making.

[0029] (2) In the present invention, the basement membrane is immersed in the filtrate in the filtrate tank through a porous drum and the dynamic real-time drum and vacuum filtration are synchronized to form the membrane. The present invention can not only achieve close fitting of the basement membrane, but also enable continuous movement with the rotation of the drum, and can have a good vacuum filtration process, high membrane production efficiency and membrane quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention, and the exemplary embodiments of the present invention and their description are used to explain the present invention and do not constitute improper limitations on the present invention.

[0031] Figure 1 It is a three-dimensional schematic diagram of a continuous vacuum filtration device according to a specific embodiment of the present invention.

[0032] Figure 2 It is a rear view of the continuous vacuum filtration membrane-making device described in a specific embodiment of the present invention.

[0033] Description of reference numerals:

[0034] 1-porous drum; 2-filtrate tank; 3-rotating joint; 4-drum driving device; 5-first film collecting roller; 6-first roller driving device; 7-first transmission roller; 8-second transmission roller; 9-third transmission roller; 10-drying box; 11-carrying platform; 12-carrying plate; 13-fourth transmission roller; 14-second film collecting roller; 15-second roller driving device. DETAILED DESCRIPTION

[0035] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0036] The present invention will be further described in detail below in conjunction with specific embodiments. It should be noted that the specific embodiments are intended to explain the present invention rather than to limit it.

[0037] A continuous vacuum filtration membrane making method, the method is to place a basement membrane on a first membrane collection roller, under the drive of a first roller driving device, the basement membrane passes through a first transmission roller, and then is wound on a porous drum, and a vacuum filtration operation is performed on the inside of the porous drum through a vacuum filtration pump and a rotary joint, so that the basement membrane is closely attached to the porous drum. The porous drum is driven to rotate by a drum driving device, so that the basement membrane is immersed in the filtrate in the filtrate tank, and the drum and vacuum filtration are synchronized dynamically and in real time, and the rotation speed of the porous drum is adjusted by controlling the drum driving device, thereby controlling the membrane load time of vacuum filtration and the membrane thickness of filtration. The filtered membrane layer passes through the second transmission roller and the third transmission roller together with the basement membrane, enters the drying box for heat treatment, passes through a rotatable carrier plate in the drying box, and then passes through a fourth transmission roller, and reaches the second membrane collection roller, and is wound and collected under the drive of the second roller driving device.

[0038] A continuous vacuum filtration membrane making device, the device comprises: a filtrate tank, a porous drum, a rotary joint, a drum driving device, a transmission roller, a bearing platform, a drying box, a carrier plate, a membrane collection roller and its driving device. The porous drum is placed in the filtrate tank and is connected to the rotary joint at the rotation center position on one side thereof, and the rotary joint is connected to a water storage tank and then to a vacuum filtration pump. The rotation center position on the other side of the porous drum is connected to the drum driving device. The first membrane collection roller is connected to the first roller driving device, the first transmission roller is close to the porous drum and is located above or obliquely above the porous drum, and the second transmission roller and the third transmission roller are placed higher than the first membrane collection roller and the first transmission roller. The drying box is placed on the bearing platform, and a rotatable carrier plate is installed inside it. The drying box is close to the third transmission roller and the fourth transmission roller, and the fourth transmission roller is located on the other side of the drying box. The second membrane collection roller is close to the fourth transmission roller and is connected to the second roller driving device. The porous drum, the film collecting roller, the transmission roller and the carrier plate are all arranged linearly.

[0039] In the above-mentioned continuous vacuum filtration membrane-making method and device, the porous drum is placed in a filtrate tank, and the basement membrane is tightly attached to the porous drum under the action of vacuum filtration. The part of the porous drum tightly attached to the basement membrane should be immersed in the filtrate, and the part of the top of the porous drum not attached to the basement membrane should be higher than the filtrate surface.

[0040] In the above-mentioned continuous vacuum filtration membrane making method and device, the surface pore size of the porous drum is 0.1 to 120 μm, which is specifically determined according to the filtrate used; or when the porous drum has larger pores, a layer of filter paper or a filter membrane with micron-level pore size, or other filtration layers with similar micropores, is attached to its surface.

[0041] In the above-mentioned continuous vacuum filtration membrane making method and device, the drum driving device, the first roller driving device, and the second roller driving device should rotate synchronously, the rotation speed of the drum driving device is 0 to 10 r / min, and the rotation speeds of the first roller driving device and the second roller driving device are set according to the drum driving device to ensure that their rotational linear speeds are the same.

[0042] In the above-mentioned continuous vacuum filtration membrane-making method and device, the base membrane is an organic microfiltration, ultrafiltration, or nanofiltration membrane base, the membrane pore size is smaller than the pore size of the porous drum, and when the base membrane is attached to the surface of the porous drum, it should be able to cover the pores on the surface of the porous drum over a width range.

[0043] In the above-mentioned continuous vacuum filtration membrane-making method and device, the heat treatment temperature of the drying box is 20-150°C.

[0044] In the above-mentioned continuous vacuum filtration membrane-making method and device, the width of the porous drum and the driving roller should be wider than the base membrane used, and the preferred range is 250 to 1200 mm.

[0045] In the above-mentioned continuous vacuum filtration membrane-making method and device, the filtrate level in the filtrate tank should be kept constant, and the filtrate can be supplemented from an external source synchronously with the progress of vacuum filtration.

[0046] In the above-mentioned continuous vacuum filtration membrane-making method and device, the first roller driving device, the first roller driving device and the supporting platform can be independently arranged or integrated into one.

[0047] Embodiment 1:

[0048] A continuous vacuum filtration membrane making device Figure 1 As shown, the device comprises: a porous drum 1, a filtrate tank 2, a rotary joint 3, a drum driving device 4, a first film collecting roller 5, a first roller driving device 6, a first transmission roller 7, a second transmission roller 8, a third transmission roller 9, a drying box 10, a bearing platform 11, a carrier plate 12, a fourth transmission roller 13, a second film collecting roller 14, and a second roller driving device 15. The porous drum 1 is placed in the filtrate tank 2 and is connected to the rotary joint 3 at the rotation center position on one side thereof. The rotary joint 3 is connected to a water storage tank and then to a vacuum filtration pump. The rotation center position on the other side of the porous drum 1 is connected to the drum driving device 4. The first film collecting roller 5 is connected to the first roller driving device 6, the first transmission roller 7 is close to the porous drum 1, and is located above or obliquely above the porous drum 1, and the second transmission roller 8 and the third transmission roller 9 are placed at positions higher than the first film collecting roller 6 and the first transmission roller 7. The drying box 10 is placed on a carrier platform 11, and a rotatable carrier plate 12 is installed inside the drying box 10. The drying box 10 is close to the third transmission roller 9 and the fourth transmission roller 13, and the fourth transmission roller 13 is located on the other side of the drying box 10. The second film collection roller 14 is close to the fourth transmission roller 13 and is connected to the second roller driving device 15. The porous drum 1, the first film collection roller 5, the second film collection roller 14, the first transmission roller 7, the second transmission roller 8, the third transmission roller 9, the fourth transmission roller 13, and the carrier plate 12 are all placed linearly.

[0049] A continuous vacuum filtration membrane making method, the method is to place an organic hydrophilic polyethersulfone microfiltration basement membrane with an average pore size of 0.1 μm on the first membrane collection roller 5, and the width of the basement membrane is 320 mm. Under the drive of the first roller driving device 6, the basement membrane passes through the first transmission roller 7 and is wound on the porous drum 1, wherein the width of the porous drum is 340 mm, and a small hole with a diameter of 1 mm penetrates the drum wall, and a layer of filter paper with a thickness of 1 to 3 μm is attached to the surface of the porous drum, and the two edges of the filter paper are fixed and sealed with tape, which can cover the pores on the surface of the porous drum within a width range. The inside of the porous drum 1 is vacuumed by a vacuum filtration pump and through a rotary joint 3, so that the basement membrane is closely attached to the porous drum 1. The part of the porous drum 1 that is tightly attached to the basement membrane accounts for about 5 / 6 of the circumferential surface of the porous drum 1 (this proportion can be adjusted according to the first transmission roller 7 and the second transmission roller 8), and the tightly attached part is immersed in a MXene aqueous dispersion with a concentration of 0.1 mg / mL (as a membrane filtrate), while the part of the top of the porous drum 1 that is not attached to the basement membrane (about 1 / 6 of the surface of the porous drum) should be higher than the filtrate surface. The vacuum degree inside the porous drum 1 is -0.07MPa (relative pressure based on atmospheric pressure) through the vacuum operation, and the porous drum 1 is driven to rotate by the drum drive device 4 at a speed of 0.2r / min, thereby synchronizing the dynamic real-time drum and vacuum filtration. The filtered membrane layer passes through the second transmission roller 8 and the third transmission roller 9 together with the basement membrane, and enters the drying box 10 on the carrier 11 for heat treatment, and the heat treatment temperature is 60°C. After passing through the rotatable carrier plate 12 in the drying box, and then passing through the fourth transmission roller 13, it reaches the second film collection roller 14, and is wound and collected under the drive of the second roller drive device 15. The rotation speeds of the first roller drive device 6 and the second roller drive device 15 are set according to the drum drive device to ensure that their rotational linear speeds are the same. During the vacuum filtration process, the filtrate level in the filtrate tank remains constant, and the filtrate is synchronously supplemented by an external source through a peristaltic pump.

[0050] Embodiment 2:

[0051] A continuous vacuum filtration membrane making method, the method is to place an organic hydrophilic PVDF microfiltration basement membrane with an average pore size of 1 μm on a first membrane collection roller 5, and the width of the basement membrane is 280 mm. Under the drive of the first roller driving device 6, the basement membrane passes through the first transmission roller 7 and is wound on a porous drum 1, wherein the width of the porous drum is 300 mm, and a small hole with a diameter of 0.5 mm penetrates the drum wall, and a layer of 30-50 μm filter paper is attached to its surface, and the width is 280 mm. The edges of the filter paper are fixed and sealed with tape, which can cover the pores on the surface of the porous drum in a width range. The inside of the porous drum 1 is vacuumed by a vacuum filtration pump and through a rotary joint 3, so that the basement membrane is closely attached to the porous drum 1. The part of the porous drum 1 that is closely attached to the basement membrane accounts for about 4 / 5 of the circumferential surface of the porous drum 1 (this proportion can be adjusted according to the first transmission roller 7 and the second transmission roller 8), and the closely attached part is immersed in a graphene oxide aqueous dispersion with a concentration of 0.05 mg / mL (as a membrane filtrate), while the part of the top of the porous drum 1 that is not attached to the basement membrane (about 1 / 5 of the surface of the porous drum) should be higher than the filtrate surface. The vacuum degree inside the porous drum 1 is -0.09 MPa (relative pressure based on atmospheric pressure) through the vacuum operation, and the porous drum 1 is driven to rotate by the drum driving device 4 at a speed of 0.5 r / min, thereby synchronizing the dynamic real-time drum and vacuum filtration. The filtered membrane layer passes through the second transmission roller 8 and the third transmission roller 9 together with the basement membrane, and enters the drying box 10 on the carrier 11 for heat treatment, and the heat treatment temperature is 80°C. After passing through the rotatable carrier plate 12 in the drying box, and then passing through the fourth transmission roller 13, it reaches the second film collection roller 14, and is wound and collected under the drive of the second roller drive device 15. The rotation speeds of the first roller drive device 6 and the second roller drive device 15 are set according to the drum drive device to ensure that their rotational linear speeds are the same. During the vacuum filtration process, the filtrate level in the filtrate tank remains constant, and the filtrate is synchronously supplemented by an external source through a peristaltic pump.

[0052] Comparative Example 1:

[0053] The difference from the continuous vacuum filtration membrane making method and device in the embodiment of the present invention is that a glass vacuum filtration device is used, including a filter cup, a sand core, a filter bottle, and a metal clip, wherein the filter bottle is located at the bottom, the sand core is connected to the filter bottle, and the filter cup is located on the upper part of the sand core and fixed by a metal clip. There is an air suction port on one side of the sand core, and the air suction port is connected to a vacuum filtration pump through a rubber air pipe.

[0054] The film making method of the above-mentioned glass vacuum filtration device is to cut the basement membrane into a suitable size, place it on the sand core, and the basement membrane can completely cover the sand core pores. The filter cup is placed on the upper part of the sand core, and the basement membrane is clamped between the filter cup and the sand core and fixed by a metal clip. The sand core air outlet and the vacuum filtration pump are connected using a rubber air pipe. The graphene oxide aqueous dispersion (as film making filtrate) with a concentration of 0.05mg / mL is poured into the filter cup, and a vacuum filtration pump is used to perform a vacuum operation, so that the vacuum degree inside the filter bottle is -0.09MPa (relative pressure based on atmospheric pressure), so that the filtrate passes through the basement membrane and forms a film layer on the surface of the basement membrane. This comparative example 1 is made by replacing the basement membrane and adding the filtrate again, which is only suitable for the vacuum filtration preparation of a monolithic membrane, and it is impossible to continuously vacuum filtration film making.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A continuous vacuum filtration membrane making device, characterized in that: include: A first film collecting roller (5), a first transmission roller (7), a porous drum (1), a second transmission roller (8), a third transmission roller (9), a drying device (10), a fourth transmission roller (13), and a second film collecting roller (14) are sequentially arranged along the film transmission direction; The porous drum (1) is partially immersed in the filtrate tank (2), the interior of the porous drum (1) is connected to a vacuum pump, and the porous drum (1) is in sliding contact with a first transmission roller (7); The first film collecting roller (5) and the first transmission roller (7) are connected via a film, and a carrier plate (12) is provided in the drying device (10); the porous drum (1), the second transmission roller (8), the third transmission roller (9), the carrier plate (12), the fourth transmission roller (13) and the second film collecting roller (14) are connected via a film.

2. The continuous vacuum filtration membrane-making device according to claim 1, characterized in that: A rotating joint (3) is provided at the rotation center position on one side of the porous drum (1), and the rotating joint (3) is connected to a water storage tank and a vacuum filtration pump in sequence. The rotation center position on the other side of the porous drum (1) is connected to a drum driving device (4).

3. The continuous vacuum filtration membrane-making device according to claim 1, characterized in that: The part of the porous drum (1) that is in close contact with the basement membrane is immersed in the filtrate, and the top part that is not in close contact with the basement membrane is higher than the surface of the filtrate.

4. The continuous vacuum filtration membrane-making device according to claim 1, characterized in that: The surface pore size of the porous drum (1) is 0.1 to 120 μm; Alternatively, a layer of filter paper or a filter membrane with micron-sized pores is attached to the surface of the porous drum (1).

5. The continuous vacuum filtration membrane-making device according to claim 1, characterized in that: The rotation speed of the drum driving device (4) is 0 to 10 r / min; Alternatively, the first transmission roller (7) is located above or obliquely above the porous drum (1).

6. The continuous vacuum filtration membrane-making device according to claim 1, characterized in that: The base membrane is an organic microfiltration, ultrafiltration, or nanofiltration membrane base, the membrane pore size is smaller than the pore size of the porous drum (1), and when the base membrane is attached to the surface of the porous drum (1), the pores on the surface of the porous drum (1) can be covered over a wide range.

7. The continuous vacuum filtration membrane-making device according to claim 1, characterized in that: The heat treatment temperature of the drying device (10) is 20-150°C.

8. The continuous vacuum filtration membrane-making device according to claim 1, characterized in that: The widths of the porous drum (1), the first transmission roller (7), the second transmission roller (8), the third transmission roller (9), and the fourth transmission roller (13) are greater than the width of the base film used; Alternatively, the widths of the porous drum (1), the first transmission roller (7), the second transmission roller (8), the third transmission roller (9), and the fourth transmission roller (13) are 250 to 1200 mm.

9. The continuous vacuum filtration membrane-making device according to claim 1, characterized in that: The filtrate level in the filtrate tank (2) is kept constant.

10. A continuous vacuum filtration membrane-making method using the device according to any one of claims 1 to 9, characterized in that: include: The base film is placed on the first film collecting roller (5), and driven by the first roller driving device (6), the base film passes through the first transmission roller (7) and then is wound around the porous drum (1), and the inside of the porous drum (1) is evacuated to make the base film closely attached to the porous drum (1); The porous drum is driven to rotate by a drum driving device (4), so that the basement membrane is immersed in the filtrate in the filtrate tank (2), and the dynamic real-time drum and vacuum filtration are synchronized, and the rotation speed of the porous drum is adjusted by controlling the drum driving device (4), thereby controlling the membrane layer load time of the vacuum filtration and the membrane layer thickness of the filtration; The filtered film layer passes through the second transmission roller (8) and the third transmission roller (9) together with the base film, enters the drying box (10) for heat treatment, passes through the rotatable carrier plate (12) in the drying box, and then passes through the fourth transmission roller (13) to reach the second film collection roller (14), and is wound and collected under the drive of the second roller driving device (15).

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