Nanofiltration membrane filtration system with membranes of different pore sizes in series

Abstract

The utility model relates to nanofiltration membrane technical field, concretely is different pore size membrane series connection nanofiltration membrane filtration system, including filter drum and inside multilayer filter membrane frame, and each layer filter membrane frame is equipped with O type sealing washer groove and liftable O type sealing washer, O type sealing washer is connected through the connecting plate and is externally connected hand control lifting assembly, realizes single -layer sealing washer independent lifting, and all hand control lifting assembly jointly connects the screw rod mechanism of servo motor drive, realizes all sealing washer synchronous lifting. The embedding of the positioning ring and the positioning ring groove enhances the sealing property, and the elastic sealing washer ensures the dynamic sealing of the lifting slide. The system supports the multilayer filter membrane batch dismounting in minutes, and the sealing washer replacement efficiency is improved by 10%, and the air tightness test pressure retention qualified rate is improved.

Description

Technical Field

[0001] This utility model relates to the field of nanofiltration membrane technology, specifically a nanofiltration membrane filtration system with membranes of different pore sizes connected in series. Background Technology

[0002] In the field of liquid separation (such as water treatment, food processing, pharmaceuticals, etc.), nanofiltration (NF) membrane filtration systems with membranes of different pore sizes connected in series can achieve multi-stage separation, improve efficiency, and extend membrane life by combining membrane units of different precision. The system composition and series connection principle are as follows: According to the molecular weight or particle size of the target analyte, filtration is carried out in stages from large to small: microfiltration (MF, 0.1-10μm) → ultrafiltration (UF, 0.01-0.1μm) → nanofiltration (NF, 1-10nm); among them, MF is used to retain suspended particles, bacteria, colloids, etc., and is often used for pretreatment to protect downstream membranes from clogging; UF retains proteins, viruses, polysaccharides, and is used to remove large molecular organic matter and reduce the fouling load of NF membranes; NF retains divalent ions and small molecular organic matter, and is used for desalination, concentration, fine separation, etc.; MF / UF commonly uses polyvinylidene fluoride (PVDF) and polyethersulfone (PES), which have strong fouling resistance; NF: polyamide (PA) composite membranes have high selectivity for monovalent / divalent ions.

[0003] Regardless of the type of membrane used for sensing and filtration, each membrane has a limited lifespan during installation and use. Therefore, membrane replacement is a crucial operation in the entire filtration system during prolonged filtration. Currently, membrane replacement is mostly done manually using tools. After installation, O-rings are installed on the outer side of the membrane and pressed into place. The installation and removal of these O-rings are often done manually using bolts, positioning rods, and other tools. This means that O-rings distributed longitudinally on different parts of the membrane need to be removed or installed separately, making it impossible to perform a unified or individual dual operation. Consequently, when replacing all the membranes in the system, the replacement of the O-rings also takes up considerable time.

[0004] To address this issue, this technical solution proposes a nanofiltration membrane filtration system with membranes of different pore sizes connected in series. Utility Model Content

[0005] The purpose of this invention is to provide a nanofiltration membrane system with membranes of different pore sizes connected in series, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A nanofiltration system with membranes of different pore sizes connected in series includes a filter cartridge. Inside the filter cartridge, multiple sets of spaced-apart membrane frames are arranged sequentially from top to bottom. A filter membrane is detachably installed on the upper side of each membrane frame. Each set of membrane frames has an O-ring groove on its upper surface. An O-ring is positioned above the O-ring groove, engaging and pressing to secure the membrane. The filter membrane to be installed is placed on the upper side of the O-ring groove. The O-ring is then lowered to press and seal the membrane located in the O-ring groove. A connecting plate is connected to the outside of the filter cartridge on one side of the O-ring, and the connecting plate moves through the filter cartridge wall towards… The external connection includes a manual lifting assembly, which is used to move the connecting plate up and down to adjust the distance between the O-ring and the O-ring groove, thus achieving independent height adjustment of a single O-ring. The side of the O-ring opposite the connecting plate is connected to a slide rod via a connecting rod. The slide rod has a groove in the filter cylinder wall. At the same time, all the manual lifting assemblies are connected to a common lifting mechanism. The lifting mechanism is used to simultaneously control the lifting of the manual lifting assemblies, thereby synchronously adjusting the position of all O-rings from their corresponding O-ring grooves, thus achieving unified lifting of the O-rings.

[0008] The connecting plate is provided with a lifting slide at the position corresponding to the cylinder wall. Elastic sealing gaskets are installed on the upper and lower sides of the connecting plate. The two sides of the elastic sealing gaskets are in real-time contact with the upper and lower sides of the inner wall of the lifting slide. When the connecting plate moves up and down, pressure is applied to the elastic sealing gaskets, but the two sides of the lifting slide are always in a sealed state.

[0009] Multiple positioning ring grooves are evenly distributed on the arc-shaped inner wall of the O-ring seal groove. A positioning ring is installed on the bottom arc surface of the O-ring seal corresponding to the positioning ring groove. The positioning ring contacts and engages with the positioning ring groove. It is used to increase the squeezing force after the O-ring seal contacts the O-ring seal groove, thereby increasing the sealing pressure on the filter membrane.

[0010] Compared with the prior art, the beneficial effects of this utility model are: by unifying the lifting of all O-rings through the screw mechanism, manual operation is freed; combined with the manual lifting component, independent adjustment of a single layer is achieved; and the filter membrane replacement time is shortened from 30 minutes to 5 minutes.

[0011] Enhanced sealing reliability: The interlocking design of the positioning ring and the positioning ring groove increases the sealing pressure by 50%, and combined with the dynamic sealing of the elastic sealing gasket, it ensures zero leakage in the 0.1MPa airtightness test.

[0012] Compatible with standard industrial processes: Supports quick replacement of MF / UF membranes and acid-alkali washing pretreatment processes for NF membranes, meeting the multi-stage filtration needs of water treatment, pharmaceutical and other scenarios. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of a nanofiltration membrane system with membranes of different pore sizes connected in series.

[0014] Figure 2 A schematic diagram of the lifting mechanism structure of a nanofiltration membrane filtration system with membranes of different pore sizes connected in series.

[0015] Figure 3 This is a partial structural diagram of the lifting mechanism in a nanofiltration system with membranes of different pore sizes connected in series.

[0016] Figure 4 for Figure 3 A schematic diagram of the structure of A in the middle.

[0017] Figure 5 for Figure 2 A magnified structural diagram of B in the diagram.

[0018] Figure 6 for Figure 1 A schematic diagram of the structure of C.

[0019] The components include: filter cartridge 10, filter membrane frame 11, O-ring groove 12, positioning ring groove 13, fixing rod 14, connecting rod 15, slide rod 16, slide groove 17, O-ring 18, positioning ring 19, servo motor 20, lead screw 21, ball nut 22, connecting block 23, internal threaded hole plate 24, adjusting screw 25, internal hex nut 26, T-shaped rotating block 27, T-shaped rotating hole plate 28, triangular connecting plate 29, connecting plate 30, lifting slide 31, and elastic sealing gasket 32. Detailed Implementation

[0020] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0021] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0022] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0023] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0024] Please see Figures 1-6 A nanofiltration membrane filtration system with membranes of different pore sizes connected in series includes a filter cartridge 10. Inside the filter cartridge 10, multiple sets of spaced filter membrane frames 11 are arranged sequentially from top to bottom. Filter membranes are detachably installed on the upper side of each filter membrane frame 11. Each filter membrane frame 11 has an O-ring groove 12 on its upper surface. An O-ring 18 is raised and lowered above the O-ring groove 12 to engage with and position the filter membrane. The filter membrane to be installed is placed on the upper side of the O-ring groove 12, and then the O-ring 18 is lowered to press and seal the filter membrane located in the O-ring groove 12. A connecting plate 30 is connected to the outside of the filter cartridge 10 on one side of the O-ring 18, and the connecting plate 30 movably passes through the filter cartridge 10. A manual lifting assembly is connected to the wall outwards. The manual lifting assembly is used to move the connecting plate 30 up and down, thereby adjusting the distance between the O-ring 18 and the O-ring groove 12, realizing independent height adjustment of a single O-ring 18. The side of the O-ring 18 opposite to the connecting plate 30 is connected to a slide rod 16 via a connecting rod 15. The slide rod 16 has a corresponding groove 17 in the wall of the filter cartridge 10. At the same time, all the manual lifting assemblies are connected to a common lifting mechanism. The lifting mechanism is used to simultaneously control the lifting of the manual lifting assemblies, thereby synchronously adjusting the position of all O-rings 18 from their corresponding O-ring grooves 12, that is, realizing the unified lifting of the O-rings 18.

[0025] A lifting slide 31 is provided on the connecting plate 30 at the position corresponding to the cylinder wall. That is, the side wall of the filter cylinder 10 is provided with a lifting slide 31 that connects to the connecting plate 30. Elastic sealing gaskets 32 are installed on the upper and lower sides of the connecting plate 30. The two sides of the elastic sealing gasket 32 ​​are in real-time contact with the upper and lower sides of the inner wall of the lifting slide 31. When the connecting plate 30 moves up and down, pressure is applied to the elastic sealing gasket 32. However, the two sides of the lifting slide 31 are always in a sealed state (because the distance that the connecting plate 30 controls the O-ring 18 to move up and down is small, the pressure applied to the elastic sealing gasket 32 ​​is also within the elastic deformation range of the elastic sealing gasket 32).

[0026] Multiple positioning ring grooves 13 are evenly opened on the arc-shaped inner wall of the O-ring groove 12. Preferably, the inner wall of the O-ring groove (12) is provided with a ring array of positioning ring grooves (13). A positioning ring 19 is installed on the bottom arc surface of the O-ring 18 corresponding to the positioning ring groove 13. The positioning ring 19 contacts and cooperates with the positioning ring groove 13. It is used to increase the squeezing force after the O-ring 18 contacts the O-ring groove 12, thereby increasing the sealing pressure on the filter membrane.

[0027] In this embodiment of the invention, in order to ensure the filtration efficiency of the filtration system, the filter membrane frame 11 is provided with three sets, and MF membrane, UF membrane and NF membrane are installed in sequence from top to bottom to filter the liquid of different components.

[0028] The manual lifting assembly includes a triangular connecting plate 29 connected to the outer end of the connecting plate 30. A T-shaped rotating perforated plate 28 is installed at the end of the triangular connecting plate 29. A T-shaped rotating block 27 is rotatably connected to the top of the T-shaped rotating perforated plate 28. An adjusting screw 25 is connected to the top of the T-shaped rotating block 27. A set of T-shaped rotating blocks 27 is threaded to the outside of the adjusting screw 25. An internal hexagonal nut 26 is installed at the top of the adjusting screw 25. By rotating the adjusting screw 25 with the help of the hexagonal nut, the adjusting screw 25 is controlled to move up and down along the T-shaped rotating block 27. Thus, with the connection of the T-shaped rotating block 27, the T-shaped rotating perforated plate 28, and the triangular connecting plate 29, the connecting plate 30 is lifted and lowered. This enables independent height adjustment of each set of O-ring seals 18, that is, independent replacement of the filter membrane on each filter membrane frame 11.

[0029] All internal threaded orifice plates 24 away from the filter cartridge 10 are connected to the lifting mechanism. The lifting mechanism includes a servo motor 20, a segmented lead screw 21 driven by the servo motor 20, a ball nut 22 threadedly connected to the lead screw 21, and an internal threaded orifice plate 24 that fixes the ball nut 22 to the manual lifting assembly.

[0030] Specifically, the bottom output end of the servo motor 20 is connected to a set of lead screws 21 via a coupling. Two more lead screw segments 21 are connected to the bottom of each lead screw 21 via connecting blocks 23. The number of lead screws 21 corresponds to the number of manual lifting components on the corresponding side. Each lead screw segment 21 is threaded with a set of ball nuts 22. The ball nuts 22 are equipped with guide devices to limit their rotation. The servo motor 20 drives the lead screws 21 to rotate. Then, under the limit of the guide devices, the rotation direction of the servo motor 20 is adjusted to control the ball nuts 22 to rise above the corresponding lead screw 21. The servo motor 20 raises or lowers the ball screws, and each set of internal threaded plate 24 is fixed to the ball screw nut 22 on the corresponding side. This enables the servo motor 20 to synchronously adjust all the manual lifting components, that is, to position and separate each set of O-rings 18 from the O-ring groove 12. (It should be noted that in order to ensure that the O-rings 18 can stably contact and position with the O-ring groove 12 under the operation of the servo motor 20, before uniform lifting, the O-rings 18 need to be adjusted to a reasonable distance from the O-ring groove 12 by the manual lifting components.)

[0031] That is, all manual lifting components are connected to a synchronous lifting mechanism consisting of a servo motor (20) and a lead screw (21).

[0032] In one embodiment of the present invention, a support column is installed at the bottom of the lead screw 21 located at the lowest side. The support column is positioned by a support sleeve or a fixed platform or other structure. This can be achieved by using existing conventional structures, which will not be described in detail here.

[0033] The O-ring groove 12 is fixed to the inner wall of the filter cartridge 10 by multiple evenly distributed fixing rods 14 on its outer circumference. At the same time, the filter cartridge 10 in this solution is only a simple illustration and does not represent the actual and complete filtration structure.

[0034] Before filtration, for MF and UF membranes, close the inlet and outlet valves of the MF / UF membrane group and drain the residual liquid in the pipeline.

[0035] Control the O-ring to rise 18, remove the old membrane, and insert the new membrane;

[0036] Then an airtightness test was conducted, in which 0.1 MPa compressed air was introduced and the pressure was maintained for 5 minutes without any leakage;

[0037] For NF membranes, first use 1% citric acid circulation to descale → clean organic matter with 0.1% NaOH → assess whether replacement is necessary; if replacement is necessary, control the O-ring to lift 18 to remove the old membrane, insert the new membrane, and then flush with low pressure for 1 hour → test the initial flux and desalination rate (must be ≥95% of the nominal value).

[0038] The working principle of this utility model is as follows: In the idle position of this device, all the aforementioned driving components (representing power elements, electrical devices, and compatible power supplies) are connected via wires. The electrical connections are completed in sequence between the working components. The detailed connection methods are well-known in the field. The following mainly describes the working principle and process, without further explanation of the electrical control.

[0039] I. Batch disassembly / installation of filter membranes

[0040] Start the servo motor 20 to rotate forward → lead screw 21 drives ball nut 22 to descend → through internal thread plate 24, all manual lifting components are linked → O-ring 18 rises synchronously and disengages from sealing groove 12.

[0041] Remove the old filter membranes layer by layer and place the new filter membranes, MF / UF / NF membranes arranged from top to bottom;

[0042] Servo motor 20 reverses → sealing ring 18 descends synchronously to press the filter membrane, and positioning ring 19 is embedded in positioning ring groove 13 to complete locking.

[0043] II. Independent Maintenance of Single-Layer Filter Membrane

[0044] Rotate the target layer's internal hex nut 26 → drive the adjusting screw 25 to push the T-shaped rotating block 27;

[0045] The transmission is conducted through the T-shaped rotating orifice plate 28 and the triangular connecting plate 29, and then the connecting plate 30 drives the individual O-ring seal 18 to rise and fall.

[0046] After replacing this filter membrane separately, rotate nut 26 in the opposite direction to reset the sealing ring.

[0047] III. Sealing Guarantee Mechanism

[0048] When the sealing ring descends: the elastic sealing gasket 32 ​​is deformed by the lifting slide 31 and always fits against the cylinder wall;

[0049] During the pressure test phase: the positioning ring 19 is wedged into the positioning ring groove 13 by the fluid pressure, forming a mechanical interlock.

[0050] It should be understood that in this application, all rotating, sliding, meshing, belt-driven and other moving parts are well lubricated and not prone to slippage or wear, and each part is provided with a corresponding protective shell. However, in the accompanying drawings of this application, the connection state of each moving part is not shown. It should also be understood that all parts in this application are made of metal or plastic materials with suitable strength in the relevant field to ensure that their structural rigidity meets the actual requirements.

[0051] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A nanofiltration membrane filtration system with membranes of different pore sizes connected in series, characterized in that, It includes a filter cartridge (10), a multi-layer filter membrane frame (11), an O-ring groove (12) on the upper surface of the filter membrane frame (11), and an O-ring (18) that mates with the groove (12); the O-ring (18) is connected to a manually operated lifting assembly that can be raised and lowered independently, and all the manually operated lifting assemblies are connected to a synchronous lifting mechanism consisting of a servo motor (20) and a lead screw (21).

2. The nanofiltration membrane system with different pore sizes connected in series according to claim 1, characterized in that, The inner wall of the O-ring groove (12) is provided with a ring array of positioning ring grooves (13), and the bottom of the O-ring (18) is fixedly connected to a positioning ring (19) that fits into the positioning ring groove (13).

3. The nanofiltration membrane system with different pore sizes connected in series according to claim 1, characterized in that, The manual lifting assembly includes a connecting plate (30) connecting to the O-ring seal (18), a triangular connecting plate (29) fixed to the connecting plate (30), a T-shaped rotating hole plate (28) hinged to the triangular connecting plate (29), a T-shaped rotating block (27) rotatably connected to the T-shaped rotating hole plate (28), and an adjusting screw (25) and an internal hex nut (26) for driving the T-shaped rotating block (27) to rise and fall.

4. The nanofiltration membrane system with different pore sizes connected in series according to claim 1, characterized in that, The lifting mechanism includes a servo motor (20), a segmented lead screw (21) driven by the servo motor (20), a ball nut (22) threadedly connected to the lead screw (21), and an internal threaded plate (24) that fixes the ball nut (22) to the manual lifting assembly.

5. The nanofiltration membrane system with different pore sizes connected in series according to claim 1, characterized in that, The filter cartridge (10) has a lifting slide (31) that connects to the connecting plate (30) on its side wall. An elastic sealing gasket (32) that is fixed to the connecting plate (30) is provided in the lifting slide (31).

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