Hollow Fiber Membrane External Pressure Resistance Testing Device and Testing Method

Abstract

The present invention discloses a device and a method for testing the external pressure resistance of a hollow fiber membrane, comprising: a transparent tube provided with two openings, one at the top and one at the bottom; a first sealing plug connected to the upper opening of the transparent tube, the first sealing plug being provided with a water injection pipe, the first end of the water injection pipe being connected to the inside of the transparent tube; a second sealing plug connected to the lower opening of the transparent tube; and at least two support rods, the first end of each support rod being fixed to the first sealing plug and the second end being connected to the second sealing plug. The present invention uses the transparent tube to construct a test space, and by injecting water into the transparent tube, the hollow fiber tube to be tested is subjected to an external pressure resistance test inside the transparent tube. In particular, it can simulate the compressive performance of the entire hollow fiber tube in a permeable state at the initial stage of the operation of the filter membrane, so as to determine whether it can resist pressure or fall off under a preset pressure.

Description

Technical Field

[0001] The present invention relates to the technical field of hollow fiber membranes, and in particular to an external pressure resistance test device and a test method for hollow fiber membranes. Background Art

[0002] Hollow fiber membranes are a type of ultrafiltration membrane with a filtration accuracy at the 0.1 micron level. Due to their excellent separation performance, they are widely used in the fields of chemical industry, electronics, pharmaceuticals, coal chemical sewage treatment, domestic sewage discharge, and the food industry. Under the drive of pressure, the raw liquid passes through a thin film with a certain pore size, and macromolecular solutes cannot pass through and remain on one side of the membrane, thereby partially purifying the macromolecular substances and achieving water purification treatment, filtering out harmful substances such as sand, colloids, heavy metals, microorganisms, and organic matter. For example, in the field of domestic drinking water treatment, in water purifiers / water purifying machines, ultrafiltration membranes with relatively large pore sizes are used as a pretreatment for reverse osmosis membranes (RO). The pore size of RO membranes is at the level of 1 / 100 of that of ultrafiltration membranes. Through cross-flow filtration or full-flow filtration, the filtration of turbidity and fine (one ten-thousandth of a micron) substances is achieved to ensure water quality and safety.

[0003] With the improvement of emission and environmental protection requirements in industrial and civil fields, and the reasonable treatment and recycling of water resources, treating highly polluted water such as urban sewage, industrial wastewater, and sewage as raw water for treatment and reuse has become an important link in water pollution control and treatment and recycling. The highly polluted raw water makes the operating pressure difference of the hollow fiber membrane higher. Structurally, the hollow fiber membrane is a filtration membrane module made of fiber filaments with a relatively large elastic modulus in cooperation with a support (reinforcing rib structure). Its mechanical strength is far less effective than that of ceramic filters. Although high-strength materials with excellent hydrophilicity and biocompatibility such as PET reinforcing ribs are used as supports in the prior art, a greater pressure is required to drive the filtration flow of the raw liquid under high pressure differences, resulting in defects such as membrane layer and membrane skin detachment during use. Summary of the Invention

[0004] In view of the defects or deficiencies existing in the prior art, according to the first aspect of the object of the present invention, an external pressure resistance test device for hollow fiber membranes is provided, including:

[0005] A transparent tube having upper and lower openings;

[0006] A first sealing plug connected to the upper opening of the transparent tube. A water injection pipe is provided on the first sealing plug, and the first end of the water injection pipe is connected to the inside of the transparent tube;

[0007] A second sealing plug connected to the lower opening of the transparent tube;

[0008] At least two support rods, with the first end of each support rod fixed to the first sealing plug and the second end connected to the second sealing plug;

[0009] A connecting seat, fixed to the second sealing plug and located inside the transparent tube. The connecting seat is used for installing the hollow fiber membrane to be tested, and the connecting seat is provided with a drain pipe communicating with the cavity of the hollow fiber membrane;

[0010] A water pump, which is connected to the second end of the water injection pipe and is used for injecting water into the transparent tube to increase the pressure, so that the water entering the transparent tube passes through the transparent tube and is discharged from the drain pipe;

[0011] Wherein, an annular accommodating groove is formed between the connecting seat and the tube wall of the transparent tube, and blocking particles are provided in the annular accommodating groove. The particle size of the blocking particles is larger than the filtration pore size of the hollow fiber membrane;

[0012] The outer wall of the transparent tube is provided with a magnetic component, and the magnetic component can move along the length direction of the transparent tube;

[0013] The blocking particles include ferromagnetic particles, and the ferromagnetic particles can be attracted by the magnetic component outside the transparent tube and move along the length direction of the hollow fiber membrane, so as to form a blocking area outside the hollow fiber membrane.

[0014] Preferably, the blocking particles further include non-ferromagnetic particles, and the density of the non-ferromagnetic particles is less than that of the ferromagnetic particles.

[0015] Preferably, the volume ratio of the non-ferromagnetic particles to the ferromagnetic particles is 7:3 - 5:5.

[0016] Preferably, the non-ferromagnetic particles are arranged in a sheet shape.

[0017] Preferably, the diameter ratio of the connecting seat to the hollow fiber membrane is less than 2:1.

[0018] Preferably, the magnetic component can rotate around the axis of the transparent tube.

[0019] Preferably, the magnetic component includes a rotating seat, a rotor, a driving motor, and a magnetic block. The rotating seat is connected to the support rod, the rotor is rotatably connected to the inner wall of the rotating seat, the driving motor is connected to the rotating seat, the rotor is provided with a toothed ring, the driving motor can drive the toothed ring to rotate, and the magnetic block is fixed to the inner wall of the rotor.

[0020] Preferably, a one-way valve is provided on the water injection pipe, a flow valve is provided on the drainage side of the one-way valve, and a pressure relief valve is further provided on the first sealing plug.

[0021] According to the second aspect of the object of the present invention, a test method for an external pressure resistance test device of a hollow fiber membrane is provided, including the following steps:

[0022] Step 1: Use a water pump to inject water into the transparent tube. When the transparent tube is filled with water, start to increase the pressure until the pressure in the transparent tube reaches a preset pressure. During this process, observe whether the hollow fiber membrane is deformed or detached by the water pressure.

[0023] Step 2: Use a water pump to inject water into the transparent tube. When the transparent tube is filled with water, start to increase the pressure until the pressure in the transparent tube reaches a first pressure value. Control the flow rate of the water entering the transparent tube through a flow valve to generate a pulsed pressure in the transparent tube. During this process, observe whether the hollow fiber membrane is deformed or detached by the water pressure.

[0024] Step 3: Use a water pump to inject water into the transparent tube. When the transparent tube is filled with water, start to increase the pressure until the pressure in the transparent tube reaches a preset pressure. Use a magnetic component to cover the blocking particles on a predetermined area of the surface of the hollow fiber membrane. During this process, observe whether the hollow fiber membrane is deformed or detached by the water pressure.

[0025] Preferably, in Step 3, control the rotation of the magnetic component to increase the rotation speed of the magnetic block to Nr / min. During this process, move the magnetic component upward by a distance H. After the blocking particles cover the predetermined area of the surface of the hollow fiber membrane, stop the rotation of the magnetic component and reset it.

[0026] Compared with the prior art, the remarkable beneficial effects of the external pressure resistance test device of the hollow fiber membrane of the present invention are as follows:

[0027] The present invention uses a transparent tube to form a test space. By injecting water into the transparent tube, the hollow fiber tube to be tested is subjected to an external pressure resistance test in the transparent tube. In particular, it can simulate the compressive performance of the entire hollow fiber tube in a permeable state at the initial stage of the operation of the filter membrane. And due to the magnifying effect of the transparent tube, it is easy for the tester to observe the shape of the hollow fiber tube to judge whether it is resistant to pressure under the preset pressure.

[0028] The present invention can realize the formation of a pulsed pressure in the transparent tube by controlling the flow rate of the flow valve provided on the water injection pipeline, and simulate the compressive performance of the hollow fiber tube when it is subjected to a pulsed pressure in the waterway.

[0029] The test device of the present invention simulates the external pressure resistance performance of the hollow fiber tube when it is partially blocked by setting blocking particles in the transparent tube, especially the joint part between the blocked part and the unblocked part, to verify whether the compressive performance of the hollow fiber tube after attaching dirt is reliable. Description of the Drawings

[0030] The accompanying drawings are not intended to be drawn to scale. In the accompanying drawings, each identical or nearly identical component shown in each figure may be denoted by the same reference numeral. For the sake of clarity, not every component is labeled in each figure. Now, embodiments of various aspects of the present invention will be described by way of example and with reference to the accompanying drawings.

[0031] Figure 1 is a schematic structural view of an external pressure resistance testing device for a hollow fiber membrane shown in the present invention.

[0032] Figure 2 is a schematic testing principle view of an external pressure resistance testing device for a hollow fiber membrane shown in the present invention.

[0033] Figure 3 is a testing state view of clogging particles covering the outer wall of a hollow fiber membrane shown in the present invention.

[0034] Figure 4 is a schematic structural view of a transposon shown in the present invention.

[0035] Figure 5 is a schematic structural view of a rotor shown in the present invention. Detailed Embodiments

[0036] For a better understanding of the technical content of the present invention, specific embodiments are hereby given and described in conjunction with the accompanying drawings as follows.

[0037] Hollow fiber membranes usually form a hollow fiber membrane module together in multiple numbers for membrane separation of the stock solution. In order to make full use of limited water resources, water with a relatively high degree of pollution is used as the raw water for treatment and then application, which poses higher technical requirements and challenges to the compressive resistance of the hollow fiber membrane. Therefore, it is necessary to propose an external pressure resistance testing device for a hollow fiber membrane, which can simulate the external pressure resistance performance of the hollow fiber tube in a non-clogging environment at the initial stage of operation, the external pressure resistance performance in a clogged environment after running for a period of time, and the external pressure resistance performance under water pressure fluctuations.

[0038]

External Pressure Resistance Testing Device for Hollow Fiber Membrane

[0039] Combined with Figure 1 as shown, the present invention proposes an external pressure resistance testing device for a hollow fiber membrane, including a transparent tube 20, a first sealing plug 11, a second sealing plug 12, a water pump 50, clogging particles 60, and a magnetic component 30.

[0040] The upper and lower openings of the transparent tube 20 are respectively connected to the first sealing plug 11 and the second sealing plug 12. A sealed environment is formed inside the transparent tube 20.

[0041] The hollow fiber membrane 40 is connected to the connecting seat 41 of the second sealing plug 12, so that the water inside the transparent tube 20 is discharged from the drain pipe of the connecting seat 41 through the hollow fiber membrane 40, forming a filtering environment.

[0042] The water pump 50 is used to increase the pressure in the transparent tube 20 to simulate the pressure environment where the hollow fiber membrane 40 is located.

[0043] The magnetic component 30 can control the distribution of the blocking particles 60 on the local surface of the hollow fiber membrane 40 to simulate the situation where the local part of the hollow fiber membrane 40 is blocked, and is used to test the external pressure resistance performance of the hollow fiber membrane 40 after being blocked.

[0044] In a preferred embodiment, the transparent tube 7 is made of high-strength plexiglass tube and has a hollow cylindrical shape. At the same time, the transparent tube 7 acts as a convex lens, playing a magnifying effect, which is beneficial to observing the morphology of the hollow fiber membrane 40 and judging whether it is flattened or detached.

[0045] Combined Figure 1-2 As shown, the first sealing plug 11 is connected to the upper opening of the transparent tube 20. The first sealing plug 11 is provided with a water injection pipe 141, and the first end of the water injection pipe 141 is connected to the inside of the transparent tube 20.

[0046] Furthermore, a pressure gauge 15 is provided on the plug body 14 of the first sealing plug 11 to detect the pressure in the transparent tube 20. The pressure of the water injected into the transparent tube 20 through the pressure gauge 15 is used to stabilize the water pressure within a predetermined pressure range for testing.

[0047] Combined Figure 2 As shown, the connecting seat 41 is fixed to the second sealing plug 12 and is located inside the transparent tube 20. The connecting seat 41 is used to install the hollow fiber membrane 40 to be tested, and the connecting seat 41 is provided with a drain pipe communicating with the cavity of the hollow fiber membrane 40.

[0048] Specifically, the connecting seat includes a support tube. The outer wall of the support tube is provided with a ferrule, and a compression nut is provided outside the ferrule. The compression nut is threadedly connected to the support tube. The hollow fiber membrane 40 is installed between the ferrule and the support tube. When the compression nut is tightened with the support tube, the ferrule presses the filter membrane to be tested on the inner wall.

[0049] Among them, the support tube is set in a stepped shape, with a cylindrical connecting part at the bottom and an external thread on the outer wall, which can be connected and matched with the internal thread of the compression nut. The ferrule is set in a hollow frustum shape, and the side wall of the ferrule is provided with a deformation seam penetrating its upper end face. When the ferrule is pressed, the gap of the deformation seam decreases, pressing the hollow fiber membrane 40 tightly.

[0050] The drain pipe communicates with the support tube, and a drain channel is formed on the inner walls of the support tube and the drain pipe.

[0051] In a specific embodiment, when installing the hollow fiber membrane, the compression nut is unscrewed from the support tube, the ferrule is pulled out, the hollow fiber membrane is sleeved on the outer wall of the support tube, then the ferrule is sleeved on the outer wall of the support tube, and then the compression nut is sleeved on, and the compression nut is tightened with the support tube. At this time, the compression nut presses the ferrule, so that the ferrule presses the hollow fiber membrane against the outer wall of the support tube.

[0052] Further, in order to prevent the first sealing plug 11 and the second sealing plug 12 from being pushed open by the internal pressure, at least two support rods 13 are arranged between the first sealing plug 11 and the second sealing plug 12. The first end of each support rod 13 is fixed to the first sealing plug 11, and the second end is connected to the second sealing plug 12. In this way, the support rod 13 plays a tensile role between the first sealing plug 11 and the second sealing plug 12, strengthening the strength of the device.

[0053] The water pump 50 is connected to the second end of the water injection pipe 141 for injecting water into the transparent tube 20 to increase the pressure, so that the water entering the transparent tube 20 passes through the transparent tube 20 and is discharged through the drain pipe. Since the drainage speed of the transparent tube 20 is fixed, by stabilizing the pumping flow rate of the water pump 50, the water pressure in the transparent tube 20 can be maintained in a stable state.

[0054] Further, as shown in Figure 2 a check valve 51 is provided on the water injection pipe 141, a flow valve 52 is provided on the drainage side of the check valve 51, and a pressure relief valve 142 is also provided on the first sealing plug 11.

[0055] In this way, during the test, the flow rate of the water injected into the transparent tube 20 can be changed through the flow valve 52 to change the water pressure in the transparent tube 20.

[0056] When the flow valve 52 is periodically adjusted, the water pressure in the transparent tube 20 can be made to fluctuate in a pulsed manner to test the compressive performance of the hollow fiber filter membrane when the water pressure pulsates, and whether it falls off or is flattened.

[0057] In some embodiments, the check valve 51 can prevent the water pressure from being transmitted in the direction of the water pump end.

[0058] When the pressure in the transparent tube 20 is too high, the pressure can be relieved through the pressure relief valve 142. In this way, the water pressure in the transparent tube 20 can be adjusted to change the pressure or maintain a constant pressure through the flow valve 52 and the pressure relief valve 142.

[0059] As shown in Figure 2 a ring-shaped accommodation groove 21 is formed between the connecting seat 41 and the tube wall of the transparent tube 20, and blocking particles 60 are provided in the ring-shaped accommodation groove 21. The particle size of the blocking particles 60 is larger than the filtration pore diameter of the hollow fiber membrane 40. In this way, when the blocking particles 60 cover the surface of the hollow fiber membrane 40, the situation where the hollow fiber membrane 40 is blocked by dirt can be simulated.

[0060] Furthermore, a magnetic component 30 is provided on the outer wall of the transparent tube 20. The magnetic component can move along the length direction of the transparent tube 20. The blocking particles 60 include ferromagnetic particles, and the ferromagnetic particles can be attracted by the magnetic component 30 outside the transparent tube 20 and move along the length direction of the hollow fiber membrane 40, so as to form a blocking area outside the hollow fiber membrane 40.

[0061] In this way, when the magnetic component 30 moves in the length direction of the transparent tube 20, it can not only make the ferromagnetic particles move longitudinally, but also will not cause pressure fluctuations in the transparent tube 20.

[0062] Among them, the ferromagnetic particles are powders made of iron and iron alloy materials, and the particle size of the powders is 150 - 500 microns, which is larger than the maximum pore diameter of several microns on the outer layer of the hollow fiber membrane 40, so as to ensure that the ferromagnetic particles will not be adsorbed into the hollow fiber membrane 40.

[0063] In a preferred embodiment, the blocking particles 60 further include non-ferromagnetic particles, and the density of the non-ferromagnetic particles is less than that of the ferromagnetic particles. Since the ferromagnetic particles are easily attached to the side wall of the transparent tube 20 after being elongated longitudinally, therefore, by adding non-ferromagnetic particles, part of the particulate matter is attracted by the water flow and attached to the surface of the hollow fiber membrane 40.

[0064] In an alternative embodiment, the non-ferromagnetic particles can be non-magnetic particles with a density greater than that of water, such as PC, polyethylene, rubber, etc., and are set in a sheet shape. The diameter of the polyethylene or nylon particles is more than 500 microns, and the thickness is less than 30 microns.

[0065] In this way, the non-ferromagnetic particles can be attached to the surface of the hollow fiber membrane 40, covering the filter holes on the surface of the hollow fiber membrane 40 to form a blocking effect and will not enter the filter holes.

[0066] Preferably, the non-magnetic particles are dyed, for example, pre-dyed red or green, which is beneficial to observing the distribution of the non-magnetic particles.

[0067] Furthermore, the volume ratio of the non-ferromagnetic particles to the ferromagnetic particles is 7:3 - 5:5. In this way, the mixed particles of the non-ferromagnetic particles and the ferromagnetic particles are deposited in the annular accommodation groove 21 in the natural state. When the blocking particles 60 close to the magnetic component 30 are attracted and move upward by the external force, the blocking particles 60 are attracted and move upward, and the ferromagnetic particles are close to the side wall of the transparent tube 20, and the non-ferromagnetic particles are attracted by the water flow and cover the surface of the hollow fiber membrane 40.

[0068] In a preferred embodiment, in order to increase the capacity of the clogging particles 60 and improve the space of the annular accommodation groove 21, the diameter ratio of the connecting seat 41 to the hollow fiber membrane 40 is less than 2:1. In this way, it is beneficial to attract and adhere non-ferromagnetic particles to the surface of the hollow fiber membrane 40 by the water flow.

[0069] Furthermore, in order to uniformly adhere non-ferromagnetic particles to the outer periphery of the hollow fiber membrane 40, the magnetic component 30 can rotate around the axis of the transparent tube 20. After the magnetic component 30 rotates, the ferromagnetic particles drive the non-ferromagnetic particles to form a stirring effect. At the same time, due to the large weight of the ferromagnetic particles, they approach the transparent tube 20 and squeeze the non-ferromagnetic particles towards the hollow fiber membrane 40.

[0070] In an alternative embodiment, as shown in Figure 4-5 FIG. 8, the magnetic component 30 includes a swivel base 31, a rotor 32, a drive motor 33, and a magnet 34. The swivel base 31 is connected to the support rod 13. The rotor 32 is rotatably connected to the inner wall of the swivel base 31. The drive motor 33 is connected to the swivel base 31. The rotor 32 is provided with a gear ring. The drive motor 33 can drive the gear ring to rotate. The magnet 34 is fixed to the inner wall of the rotor 32.

[0071] Among them, two through holes 312 are provided on the swivel base 31, which are respectively connected to the outer walls of the two support rods 13. The swivel base 31 is arranged as two crescent-shaped arc blocks butt-jointed. A groove 311 is provided on the inner wall of the swivel base 31. A protrusion 321 is provided on the outer wall of the rotor 32. The protrusion can be stuck in the groove 311. A gear ring 322 is provided on the upper edge of the rotor 32. When the drive motor 33 rotates, the gear at its output end meshes with the gear ring 322, and the rotor 32 can be driven to rotate relative to the swivel base 31.

[0072] Thus, the rotor 32 drives the magnet 34 on the inner wall to rotate around the axis of the transparent tube 20, forming a stirring effect on the ferromagnetic particles inside the transparent tube 20.

[0073]

Hollow Fiber Membrane External Pressure Resistance Testing Method

[0074] A technical solution is proposed in the second aspect of the present invention. A hollow fiber membrane external pressure resistance testing method includes the following steps:

[0075] (1) Use a water pump 50 to inject water into the transparent tube 20. When the transparent tube 20 is filled with water, start to increase the pressure until the pressure inside the transparent tube 20 reaches a preset pressure. During this process, observe whether the hollow fiber membrane 40 is deformed or detached by the water pressure;

[0076] (2) Use a water pump 50 to inject water into the transparent tube 20. After the transparent tube 20 is filled with water, start to increase the pressure until the pressure in the transparent tube 20 reaches the first pressure value. Control the flow rate of the water entering the transparent tube 20 through the flow valve 52 to generate a pulsed pressure in the transparent tube 20. During this process, observe whether the hollow fiber membrane 40 is deformed or detached by the water pressure.

[0077] (3) Use a water pump 50 to inject water into the transparent tube 20. After the transparent tube 20 is filled with water, start to increase the pressure until the pressure in the transparent tube 20 reaches the preset pressure. Use the magnetic component 30 to cover the predetermined area on the surface of the hollow fiber membrane 40 with the blocking particles 60. During this process, observe whether the hollow fiber membrane 40 is deformed or detached by the water pressure.

[0078] Among them, the test in the aforementioned step (1) is a conventional external pressure resistance test.

[0079] In some embodiments, the implementation of the conventional external pressure resistance test specifically includes the following process:

[0080] Use the water pump 50 to inject water into the transparent tube 20 through the water injection pipe 141. After the water is full, control the flow rate of the water entering the transparent tube 20 through the flow valve 52 to control the pressure in the transparent tube 20.

[0081] During the test, control the pressure increase rate to be less than 0.1 Mpa per minute until it increases to 0.3 Mpa. When it reaches 0.3 Mpa, observe whether the hollow fiber membrane 40 is deformed. When it is not deformed, increase the pressure at a rate of 0.01 Mpa per minute. After increasing the pressure for 1 minute each time, stop observing for 30 seconds until the hollow fiber membrane 40 is deformed or detached under pressure, and test the ultimate external pressure resistance performance.

[0082] Among them, step (2) is a fluctuating pressure test.

[0083] In a specific embodiment, the difference from step (1) is that after increasing the pressure to 0.25 Mpa, control the speed of pressure increase through the flow valve 52, and stabilize the pressure at 0.25 Mpa ± 0.05 Mpa. By controlling the speed of pressure fluctuation, test the external pressure resistance performance of the hollow fiber membrane 40 under pulsed pressure.

[0084] Among them, step (3) is a blocked external pressure resistance test.

[0085] In a specific embodiment, the difference from step (1) is that after increasing the pressure to 0.2 Mpa, move the magnetic component 30 from the highest point to the lowest point, and then move the magnetic component 30 upward by a certain distance, so that the non-ferromagnetic particles are squeezed by the water flow flowing towards the hollow fiber membrane 40 and adhere to the surface of the hollow fiber membrane 40 to form a partial coverage.

[0086] At this time, observe the covering position of the non-ferromagnetic particles and the morphology of the hollow fiber membrane 40, and continuously increase the pressure.

[0087] Specifically, the pressure increase rate is 0.01 Mpa per minute, and pay attention to observing the morphology of the covered area, non-covered area and boundary area of the hollow fiber membrane 40 until one of the areas is squeezed and deformed.

[0088] Preferably, in step c, control the rotation of the magnetic component 30 to increase the rotation speed of the magnetic block 34 from 0 to 180 r / min. During this process, make the distance H that the magnetic component 30 moves upward, and after the blocking particles 60 cover a predetermined area on the surface of the hollow fiber membrane 40, stop the rotation of the magnetic component 30 and reset it.

[0089] Among them, within the first few seconds of the rotation of the magnetic component 30, the stirring effect is the best. At this time, move the magnetic component 30 upward to a predetermined height, such as the position of half the height of the hollow fiber membrane 40.

[0090] In this way, the ferromagnetic particles drive the non-ferromagnetic particles to form a stirring effect. At the same time, due to the large weight of the ferromagnetic particles, they approach the transparent tube 20 and squeeze the non-ferromagnetic particles towards the hollow fiber membrane 40, making it easy for the non-ferromagnetic particles to be pressed onto the surface of the hollow fiber membrane 40 by the water pressure to form a coverage. After the coverage is formed, lower the magnetic component 30 to its original position to make the ferromagnetic particles fall into the annular accommodation groove 21, avoiding interference with the observation caused by the ferromagnetic particles.

[0091] After the test is completed, clean the hollow fiber membrane 40, recover the ferromagnetic particles and non-ferromagnetic particles, mix and separate the ferromagnetic particles and non-ferromagnetic particles, and re-formulate and use them when used next time.

[0092] Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Those with ordinary knowledge in the technical field to which the present invention pertains can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the claims.

Claims

1. A hollow fiber membrane external pressure resistance test device, characterized in that, Comprising: A transparent tube (20) provided with upper and lower openings; A first sealing plug (11) connected to the upper opening of the transparent tube (20), at least one water injection pipe (141) being provided on the first sealing plug (11), and a first end of the water injection pipe (141) being connected to the inside of the transparent tube (20); A second sealing plug (12) connected to the lower opening of the transparent tube (20); At least two support rods (13), a first end of each support rod (13) being fixed to the first sealing plug (11) and a second end being connected to the second sealing plug (12); A connection seat (41) fixed to the second sealing plug (12) and located inside the transparent tube (20), the connection seat (41) being used for mounting a hollow fiber membrane (40) to be tested, and the connection seat (41) being provided with a drain pipe communicating with a cavity of the hollow fiber membrane (40); A water pump (50) connected to a second end of the water injection pipe (141) for injecting water into the transparent tube (20) to increase the pressure, and the water entering the transparent tube (20) passes through the transparent tube (20) and is discharged through the drain pipe; Wherein, an annular accommodation groove (21) is formed between the connection seat (41) and the tube wall of the transparent tube (20), and blocking particles (60) are provided in the annular accommodation groove (21), and a particle size of the blocking particles (60) is larger than a filtration pore diameter of the hollow fiber membrane (40); A magnetic component (30) is provided on an outer wall of the transparent tube (20), and the magnetic component is arranged to be movable along a longitudinal length direction of the transparent tube (20); The blocking particles (60) include ferromagnetic particles, and the ferromagnetic particles can be attracted by the magnetic component (30) outside the transparent tube (20) and move along a length direction of the hollow fiber membrane (40), so as to form a blocking area outside the hollow fiber membrane (40).

2. The hollow fiber membrane external pressure resistance testing device according to claim 1, wherein The blocking particles (60) further include non-ferromagnetic particles, and a density of the non-ferromagnetic particles is less than a density of the ferromagnetic particles.

3. The hollow fiber membrane external pressure resistance testing device according to claim 2, characterized in that, A volume ratio of the non-ferromagnetic particles to the ferromagnetic particles is 7:3 - 5:

5.

4. The hollow fiber membrane external pressure resistance testing device according to claim 2, characterized in that The non-ferromagnetic particles are arranged to be sheet-shaped.

5. The hollow fiber membrane external pressure resistance test device according to claim 1, wherein A diameter ratio of the connection seat (41) to the hollow fiber membrane (40) is less than 2:

1.

6. The hollow fiber membrane external pressure resistance test device according to claim 1, characterized in that The magnetic component (30) can rotate around an axis of the transparent tube (20).

7. The hollow fiber membrane external pressure resistance test device according to claim 1, characterized in that, The magnetic component (30) includes a rotating seat (3, a rotor (32), a driving motor (33), and a magnetic block (34); The rotating seat (31) is connected to the support rod (13), the rotor (32) is rotatably connected to an inner wall of the rotating seat (31), the driving motor (33) is connected to the rotating seat (31), the rotor (32) is provided with a toothed ring, the driving motor (33) can drive the toothed ring to rotate, and the magnetic block (34) is fixed to an inner wall of the rotor (32).

8. The hollow fiber membrane external pressure resistance test device according to any one of claims 1-7, characterized in that, A one-way valve (51) is provided on the water injection pipe (141), and a flow valve (52) is provided on a drainage side of the one-way valve (51).

9. The method for testing the external pressure resistance of a hollow fiber membrane of the external pressure resistance testing device for a hollow fiber membrane according to claim 7, characterized in that, Including the following steps: Step 1: Control the water pump (50) to inject water into the transparent tube (20). After the transparent tube (20) is filled with water, start pressurizing until the pressure in the transparent tube (20) reaches the preset pressure. During this process, observe whether the hollow fiber membrane (40) is deformed or detached by the water pressure; Step 2: Use the water pump (50) to inject water into the transparent tube (20). After the transparent tube (20) is filled with water, start pressurizing until the pressure in the transparent tube (20) reaches the first pressure value. Control the flow rate of the water entering the transparent tube (20) through the flow valve (52) to generate a pulsating pressure in the transparent tube (20). During this process, observe whether the hollow fiber membrane (40) is deformed or detached by the water pressure; Step 3: Use the water pump (50) to inject water into the transparent tube (20). After the transparent tube (20) is filled with water, start pressurizing until the pressure in the transparent tube (20) reaches the preset pressure. Use the magnetic component (30) to cover the blocking particles (60) on the predetermined area of the surface of the hollow fiber membrane (40). During this process, observe whether the hollow fiber membrane (40) is deformed or detached by the water pressure.

10. The method for testing the external pressure resistance of the hollow fiber membrane according to claim 9, characterized in that, In Step 3, control the magnetic component (30) to rotate, so that the rotation speed of the magnet (34) is increased from 0 to Nr / min. During this process, move the magnetic component (30) upward by a distance H. After the blocking particles (60) cover the predetermined area of the surface of the hollow fiber membrane (40), stop the rotation of the magnetic component (30) and reset it.

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