Method for packaging free end of hollow fiber membrane and hollow fiber membrane bundle

Abstract

The invention provides a hollow fiber membrane free end packaging method and a hollow fiber membrane bundle, and particularly relates to the technical field of water treatment. The packaging method for the free end of the hollow fiber membrane comprises the following steps: A, sealing the free end of a hollow fiber membrane bundle, dipping the hollow fiber membrane bundle in a water-based silicone oil solution, taking out the hollow fiber membrane bundle, airing the hollow fiber membrane bundle, and carrying out primary end cutting to expose inner holes of the hollow fiber membrane; and B, inserting the free end subjected to primary end cutting into packaging glue for curing, and then taking out the free end to obtain the packaged free end. According to the packaging method, the bursting strength of the free end packaging structure stably exceeds 0.4 MPa, and the long-term stable operation requirement under the high-pressure working condition is met. The packaging method is simple and easy to implement, reduces the glue consumption, does not need precise cutting equipment, shortens the working procedures, and is suitable for large-scale industrial production.

Description

Technical Field

[0001] The present invention relates to the technical field of water treatment, and particularly to a method for encapsulating the free end of a hollow fiber membrane and a hollow fiber membrane bundle. Background Art

[0002] Traditional hollow fiber membrane modules adopt a rigid fixed structure at both ends. During operation, the distance between the membrane filaments cannot be dynamically adjusted, resulting in the easy accumulation of pollutants in the gaps between the membrane filaments to form a bridging effect. This not only causes a significant decrease in the membrane flux (the flux decay can reach 40%-60% after 100 hours), but also increases the risk of membrane filament breakage.

[0003] To solve this problem, free-end hollow fiber membrane modules have emerged. By keeping one end of the membrane filaments in a free state, the fluid shear force is used to make the membrane filaments swing to break the pollutant deposition layer, which can reduce the pollution rate by 30%-50%, but this poses higher requirements for the encapsulation process.

[0004] In the prior art, although some encapsulation processes achieve reliable sealing, due to process limitations, only 2-9 membrane filaments can be processed in each batch. Even with expensive automated equipment, the production cost remains high. Other encapsulation processes are suitable for large-scale production, but have problems such as complex and time-consuming processes, large glue consumption, and strict cutting accuracy requirements (the error needs to be <0.1 mm).

[0005] The current free-end membrane module encapsulation technology still faces multiple challenges of low production efficiency, complex processes, and high costs. There is an urgent need to develop a new type of high-efficiency and low-cost large-scale encapsulation process to meet market demands.

[0006] In view of this, the present invention is specifically proposed. Summary of the Invention

[0007] One of the objectives of the present invention is to provide a method for encapsulating the free end of a hollow fiber membrane, aiming to solve at least one of the above technical problems in the prior art.

[0008] Another objective of the present invention is to provide a hollow fiber membrane bundle.

[0009] To achieve the above objectives of the present invention, the following technical solutions are specifically adopted: The first aspect of the present invention provides a method for encapsulating the free end of a hollow fiber membrane, including the following steps: A. After sealing the free end of the hollow fiber membrane bundle, immerse it in an aqueous silicone oil solution, take it out and dry it, and then perform a first cut of the head to expose the inner hole of the hollow fiber membrane; B. Insert the free end after the first cut of the head into the encapsulation glue for curing, and then take out the free end to obtain the encapsulated free end.

[0010] Further, in step A, after impregnation in the aqueous silicone oil solution, the height of the aqueous silicone oil layer formed at the free end is the first height after the first cut of the head.

[0011] In step B, the insertion depth into the encapsulating glue is the first depth.

[0012] Further, the first height is greater than the first depth.

[0013] Further, the first height is greater than the first depth by more than 1 cm.

[0014] Further, the first depth is 5 - 20 mm.

[0015] Further, the mass concentration of the aqueous silicone oil solution is 5 - 20%.

[0016] And / or, the aqueous silicone oil includes at least one of polyether-modified silicone oil, amino-modified silicone oil, carboxyl-modified silicone oil, and hydroxyl-modified silicone oil.

[0017] Further, the encapsulating glue includes at least one of epoxy resin glue, polyurethane glue, phenolic resin glue, polyisocyanate glue, polyvinyl acetate glue, polyethylene-vinyl acetate glue, acrylate glue, polystyrene glue, alkyd resin glue, and cellulose glue.

[0018] The second aspect of the present invention provides a hollow fiber membrane bundle composed of a plurality of hollow fiber membrane filaments; The hollow fiber membrane filaments include sealed ends and open ends located at both ends of the filaments; The sealed ends are sealed by the encapsulation method described in the first aspect.

[0019] Further, the diameter of the hollow fiber membrane filaments is 0.2 - 5 mm.

[0020] Further, the material of the hollow fiber membrane filaments includes at least one of polyvinylidene fluoride, polytetrafluoroethylene, polyethersulfone, polysulfone, polypropylene, polyethylene, polyvinyl chloride, polyacrylonitrile, and polyisoprene.

[0021] Compared with the prior art, the present invention has at least the following beneficial effects: The encapsulation method provided by the present invention can effectively block the direct bonding between the encapsulation glue and the surface of the membrane filaments by impregnating the free end of the membrane bundle in an aqueous silicone oil solution to form a soluble temporary isolation layer. After curing, the membrane filaments can be completely withdrawn from the glue plugs, ensuring that there is no colloid adhesion between the hollow fiber membranes, and at the same time realizing the dynamic swing function of the free end. The aqueous silicone oil has water-soluble characteristics and can be completely removed by subsequent water washing, avoiding the membrane pore blockage or performance deterioration caused by the residue of traditional release agents. In addition, by controlling the immersion depth of the membrane bundle inserted into the encapsulation glue, the axial dimension of the cured seal plug can be directly determined, realizing the directional regulation of the sealing strength while simplifying the process. This method enables the burst strength of the free-end encapsulation structure to stably exceed 0.4 MPa, meeting the long-term stable operation requirements under high-pressure working conditions. This encapsulation method is simple and easy to implement, reduces the amount of glue used, does not require precision cutting equipment, shortens the process, and is suitable for large-scale industrial production.

[0022] Due to the advantages of the above-mentioned encapsulation method, the manufacturing cost of the hollow fiber membrane bundle provided by the present invention is reduced, the usage cost of the downstream industry is reduced, and the development of the downstream industry is promoted. Description of the Drawings

[0023] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Figure 1 It is a schematic diagram of the encapsulation method for the free end of the hollow fiber membrane provided by the present invention.

[0025] Reference numerals: 1 - hollow fiber membrane filament; 2 - aqueous silicone oil coating; 3 - encapsulation glue. Detailed Embodiments

[0026] To make the objectives, technical solutions, and advantages of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, rather than all, of the embodiments of the present invention.

[0027] In the following text, the terms "comprising", "having" and their cognates that can be used in various embodiments of the present invention are only intended to represent specific features, numbers, steps, operations, elements, components or combinations of the foregoing items, and should not be construed as precluding the existence of one or more other features, numbers, steps, operations, elements, components or combinations of the foregoing items or the possibility of adding one or more features, numbers, steps, operations, elements, components or combinations of the foregoing items first.

[0028] The first aspect of the present invention provides a method for encapsulating the free end of a hollow fiber membrane, comprising the following steps: A. After sealing the free end of the hollow fiber membrane bundle, impregnate it in an aqueous silicone oil solution, take it out and dry it, and then perform a first cutting of the head to expose the inner hole of the hollow fiber membrane; B. Insert the free end after the first cutting into the encapsulating glue for curing, and then take out the free end to obtain the encapsulated free end.

[0029] The encapsulation method provided by the present invention forms a soluble temporary isolation layer by impregnating the free end of the membrane bundle in an aqueous silicone oil solution, which can effectively block the direct bonding between the encapsulating glue and the surface of the membrane filaments. After curing, the membrane filaments can be completely withdrawn from the glue plug, ensuring that there is no colloid adhesion between the hollow fiber membranes, and at the same time realizing the dynamic swing function of the free end. The aqueous silicone oil has water-soluble characteristics and can be completely removed by subsequent water washing, avoiding the membrane pore blockage or performance deterioration caused by the residue of traditional release agents. In addition, by controlling the immersion depth of the membrane bundle inserted into the encapsulating glue, the axial dimension of the cured sealing plug can be directly determined, realizing the directional regulation of the sealing strength while simplifying the process. This method enables the bursting strength of the free end encapsulation structure to stably exceed 0.4 MPa, meeting the long-term stable operation requirements under high-pressure working conditions. This encapsulation method is simple and easy to implement, reduces the glue consumption, does not require precision cutting equipment, shortens the process, and is suitable for large-scale industrial production.

[0030] Before the impregnation treatment, it is necessary to check whether the free ends of the hollow fiber membrane bundle are neat. If the free ends are not aligned, cutting of the head should be performed to ensure uniform impregnation depth of the membrane bundle. In addition, if the free ends need to be fixed subsequently, the cutting of the head should be completed before the fixing operation to ensure good fixing effect.

[0031] In some embodiments of the present invention, a quick-drying glue is used to seal the free end membrane filaments in the hollow fiber membrane bundle to facilitate the subsequent impregnation process. By pre-sealing the membrane filaments, it can be ensured that the hollow fiber membrane bundle maintains a uniform impregnation depth during the impregnation process and prevents the aqueous silicone oil from entering the inner holes of the membrane filaments.

[0032] Further, in step A, after impregnation in the aqueous silicone oil solution, an aqueous silicone oil layer is formed at the free end, and the height of the aqueous silicone oil layer after the first cutting of the head is the first height.

[0033] The first end cutting is to cut off the quick-drying glue sealing layer at the end of the membrane bundle after being impregnated with aqueous silicone oil, accurately exposing the inner holes of the hollow fiber membranes, which not only ensures the integrity of the fluid channels but also forms a flat end face reference to improve the positioning accuracy of subsequent glue encapsulation.

[0034] In step B, the insertion depth into the encapsulating glue is the first depth.

[0035] Furthermore, the first height is greater than the first depth.

[0036] As Figure 1 shown in the schematic diagram of the method for encapsulating the free end of the hollow fiber membrane provided by the present invention, a water-based silicone oil coating 2 is formed on the surface of the free end of the hollow fiber membrane filaments 1, and this coating has a specific first height. During the encapsulation process, the free end with the water-based silicone oil coating 2 is immersed in the encapsulating glue 3, and the immersion depth is the first depth. Through process control, it is ensured that the first height > the first depth to achieve a reliable encapsulation effect.

[0037] Furthermore, the first height is more than 1 cm greater than the first depth. To ensure the encapsulation quality, the immersion depth of the encapsulating glue (i.e., the first depth) should be controlled to be at least 1 cm lower than the attachment height of the water-based silicone oil on the surface of the membrane filaments (i.e., the first height). This design can effectively avoid the glue overflowing over the silicone oil protection layer due to uneven arrangement of the membrane filaments, thereby preventing the bonding between the membrane filaments and ensuring the freedom of movement of the membrane filaments.

[0038] Furthermore, the first depth is 5 - 20 mm.

[0039] When the first depth is less than 5 mm, it is difficult for the bursting strength of the free end encapsulation to reach the minimum standard of 0.4 MPa; while when the first depth exceeds 20 mm, it will cause unnecessary losses of the membrane filament material and the encapsulating glue.

[0040] Typically but not restrictively, the first depth can be, for example, 5 mm, 8 mm, 10 mm, 12 mm, 15 mm, 18 mm or 20 mm, or any value within the range of 5 mm - 20 mm.

[0041] Furthermore, the mass concentration of the aqueous silicone oil solution is 5 - 20%.

[0042] The mass concentration of the aqueous silicone oil solution needs to be controlled within an appropriate range: when the concentration is higher than 20%, although the demolding effect can be significantly improved, it will lead to an increase in production costs; on the contrary, if the concentration is lower than 5%, it is difficult to effectively block the bonding between the membrane filaments and the glue, resulting in demolding failure.

[0043] Typically but not restrictively, the mass concentration of the aqueous silicone oil solution can be, for example, 5%, 8%, 10%, 12%, 15%, 18% or 20%, or can also be any value within the range of 5% to 20%.

[0044] And / or, the aqueous silicone oil includes at least one of polyether-modified silicone oil, amino-modified silicone oil, carboxyl-modified silicone oil and hydroxyl-modified silicone oil.

[0045] Silicone oil can isolate the membrane filaments from the encapsulating glue, making it easy to pull out the cured membrane filaments. However, the silicone oil remaining on the membrane filaments will contaminate the membrane filaments and is difficult to remove. Using aqueous silicone oil can overcome this defect.

[0046] Furthermore, the encapsulating glue includes at least one of epoxy resin glue, polyurethane glue, phenolic resin glue, polyisocyanate glue, polyvinyl acetate glue, polyethylene-vinyl acetate glue, acrylate glue, polystyrene glue, alkyd resin glue, and cellulose glue.

[0047] The second aspect of the present invention provides a hollow fiber membrane bundle, which is composed of a plurality of hollow fiber membrane filaments; The hollow fiber membrane filaments include sealed ends and open ends located at both ends of the membrane filaments; The sealed ends are sealed by the encapsulation method described in the first aspect.

[0048] For the hollow fiber membrane bundle provided by the present invention, due to the advantages of the above-mentioned encapsulation method, the preparation cost of the prepared hollow fiber membrane bundle is reduced, the use cost of the downstream industry is reduced, and the development of the downstream industry is promoted.

[0049] Furthermore, the diameter of the hollow fiber membrane filaments is 0.2 to 5 mm.

[0050] Typically but not restrictively, the diameter of the hollow fiber membrane filaments can be, for example, 0.2 mm, 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm or 5 mm, or can also be any value within the range of 0.2 mm to 5 mm.

[0051] Furthermore, the material of the hollow fiber membrane filaments includes at least one of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polyethersulfone (PES), polysulfone (PSF), polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC), polyacrylonitrile (PAN) and poly-4-methyl-1-pentene (PMP).

[0052] The present invention will be further illustrated by specific examples and comparative examples below. However, it should be understood that these examples are only for more detailed illustration and should not be construed as limiting the present invention in any way. For the raw materials used in the examples and comparative examples of the present invention, unless otherwise specified, they are carried out under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used without indicating the manufacturer are all conventional products that can be obtained through commercial purchase.

[0053] Example 1 In this example, the free end of the hollow fiber membrane bundle was encapsulated, and the specific method was as follows: (1) The free end of the sorted hollow fiber membrane bundle was subjected to a sealing head treatment. Quick-drying glue was evenly coated on the cut ends of the membrane filaments by brushing, and the brushing height was 3 mm.

[0054] (2) After the quick-drying glue was completely cured, the glue-coated end was immersed in an amino-modified silicone oil solution with a mass concentration of 10%, and the dipping depth was controlled to be 25 mm.

[0055] (3) The impregnated membrane bundle was taken out, and after air-drying, the glue-coated end was cut off, and the cutting length was 5 mm to ensure that the inner holes of the hollow fibers were completely exposed.

[0056] (4) The trimmed membrane bundle was inserted into the encapsulation glue, and the dipping depth was controlled to be 8 mm, and it was left standing until completely cured.

[0057] (5) The membrane bundle was slowly pulled out vertically from the cured glue to obtain a finished hollow fiber membrane bundle with a free-end encapsulation structure.

[0058] Example 2 In this example, the free end of the hollow fiber membrane bundle was encapsulated, and the specific method was as follows: (1) The free end of the sorted hollow fiber membrane bundle was subjected to a sealing head treatment. Quick-drying glue was evenly coated on the cut ends of the membrane filaments by brushing, and the brushing height was 10 mm.

[0059] (2) After the quick-drying glue was completely cured, the glue-coated end was immersed in an amino-modified silicone oil solution with a mass concentration of 10%, and the dipping depth was controlled to be 30 mm.

[0060] (3) The impregnated membrane bundle was taken out, and after air-drying, the glue-coated end was cut off, and the cutting length was 12 mm to ensure that the inner holes of the hollow fibers were completely exposed.

[0061] (4) The trimmed membrane bundle was inserted into the encapsulation glue, and the dipping depth was controlled to be 5 mm, and it was left standing until completely cured.

[0062] (5) The membrane bundle was slowly pulled out vertically from the cured glue to obtain a finished hollow fiber membrane bundle with a free-end encapsulation structure.

[0063] Example 3 In this example, the free end of the hollow fiber membrane bundle is encapsulated, and the specific method is as follows: (1) Perform a sealing treatment on the free end of the sorted hollow fiber membrane bundle. Use a brush coating method to evenly coat the cut ends of the membrane filaments with fast-drying glue, and the brush coating height is 3 mm.

[0064] (2) Immerse the free end in an amino-modified silicone oil solution with a mass concentration of 10%, and control the immersion depth to be 40 mm.

[0065] (3) Take out the immersed membrane bundle, cut off the glue-coated end after air drying, and the cutting length is 5 mm to ensure that the inner holes of the hollow fibers are completely exposed.

[0066] (4) Insert the trimmed membrane bundle into the encapsulating glue, control the immersion depth to be 20 mm, and let it stand until completely cured.

[0067] (5) Slowly pull out the membrane bundle vertically from the cured glue to obtain a finished hollow fiber membrane bundle with a free end encapsulation structure.

[0068] Example 4 In this example, the free end of the hollow fiber membrane bundle is encapsulated, and the specific method is as follows: (1) Perform a sealing treatment on the free end of the sorted hollow fiber membrane bundle. Use a brush coating method to evenly coat the cut ends of the membrane filaments with fast-drying glue, and the brush coating height is 3 mm.

[0069] (2) Immerse the free end in an amino-modified silicone oil solution with a mass concentration of 10%, and control the immersion depth to be 20 mm.

[0070] (3) Take out the immersed membrane bundle, cut off the glue-coated end after air drying, and the cutting length is 5 mm to ensure that the inner holes of the hollow fibers are completely exposed.

[0071] (4) Insert the trimmed membrane bundle into the encapsulating glue, control the immersion depth to be 10 mm, and let it stand until completely cured.

[0072] (5) Slowly pull out the membrane bundle vertically from the cured glue to obtain a finished hollow fiber membrane bundle with a free end encapsulation structure.

[0073] Example 5 In this example, the free end of the hollow fiber membrane bundle is encapsulated, and the specific method is as follows: (1) Perform a sealing treatment on the free end of the sorted hollow fiber membrane bundle. Use a brush coating method to evenly coat the cut ends of the membrane filaments with fast-drying glue, and the brush coating height is 3 mm.

[0074] (2) Immerse the free end in an amino-modified silicone oil solution with a mass concentration of 10%, and control the immersion depth to be 10 mm.

[0075] (3) Take out the impregnated membrane bundle, cut off the glue-coated end after air drying, and the cutting length is 5 mm to ensure that the inner holes of the hollow fiber membranes are completely exposed.

[0076] (4) Insert the trimmed membrane bundle into the encapsulation glue, control the immersion depth to be 10 mm, and let it stand until completely cured.

[0077] (5) Since the length of the membrane filaments impregnated with aqueous silicone oil is only 5 mm after cutting the heads, which is lower than the immersion depth of the encapsulation glue, the membrane bundle cannot be pulled out from the cured glue.

[0078] Example 6 In this example, the free ends of the hollow fiber membrane bundles are encapsulated, and the specific method is as follows: (1) Perform a sealing head treatment on the free ends of the sorted hollow fiber membrane bundles. Use a brushing method to evenly coat the quick-drying glue on the cut ends of the membrane filaments, and the brushing height is 3 mm.

[0079] (2) Immerse the free ends into an amino-modified silicone oil solution with a mass concentration of 10%, and control the immersion depth to be 15 mm.

[0080] (3) Take out the impregnated membrane bundle, cut off the glue-coated end after air drying, and the cutting length is 5 mm to ensure that the inner holes of the hollow fiber membranes are completely exposed.

[0081] (4) Insert the trimmed membrane bundle into the encapsulation glue, control the immersion depth to be 10 mm, and let it stand until completely cured.

[0082] (5) Slowly pull out the membrane bundle vertically from the cured glue to obtain the finished product of the hollow fiber membrane bundle with a free-end encapsulation structure.

[0083] Test Example Conduct a burst strength test on the hollow fiber membrane bundles encapsulated in the examples, and the obtained data are shown in Table 1 below.

[0084] Table 1

[0085] As can be seen from Table 1, in Example 1, the difference between the first height and the first depth is 12 mm, the first depth is 8 mm, and the bursting strength of the free-end encapsulation structure is 0.47 MPa, which meets the product standards and usage requirements and is a relatively reasonable implementation scheme. In Example 2, the difference between the first height and the first depth is 13 mm, the first depth is 5 mm, and the bursting strength of the free-end encapsulation structure is 0.41 MPa, which meets the product standards and usage requirements. However, in Example 2, the quick-drying glue is applied at the cut end of the membrane filament, and the brushing height is 10 mm, which is too high, wasting the quick-drying glue, water-based silicone oil, and membrane filaments. In Example 3, the difference between the first height and the first depth is 15 mm, the first depth is 20 mm, and the bursting strength of the free-end encapsulation structure is 0.68 MPa, which meets the product standards and usage requirements and can be used for products with slightly higher bursting strength requirements. In Example 4, the difference between the first height and the first depth is 5 mm, the first depth is 10 mm, and the bursting strength of the free-end encapsulation structure is 0.51 MPa, which meets the product standards and usage requirements. However, in Example 4, there is a small amount of slight adhesion of the membrane filaments, which will affect the freedom of movement of the membrane filaments. In Example 5, the difference between the first height and the first depth is -5 mm, the first depth is 10 mm, and the membrane bundle cannot be pulled out from the curing glue, failing to meet the product standards and usage requirements. In Example 6, the difference between the first height and the first depth is 0 mm, the first depth is 10 mm, the bursting strength of the free-end encapsulation structure is 0.50 MPa, and there is partial adhesion of the membrane filaments, affecting the freedom of movement of the membrane filaments and failing to meet the product standards and usage requirements.

[0086] Finally, it should be noted that the above-described embodiments are only specific implementation manners of the present invention, used to illustrate the technical solutions of the present invention, and are not intended to limit them. The protection scope of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: Any person skilled in the art within the technical scope disclosed by the present invention can still modify the technical solutions recorded in the foregoing embodiments, or can easily think of changes, or perform equivalent replacements on some of the technical features; and these modifications, changes, or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A method for encapsulating the free end of a hollow fiber membrane, characterized in that, It includes the following steps: A. After sealing the free end of the hollow fiber membrane bundle, impregnate it in an aqueous silicone oil solution. After taking it out and drying, perform a first cut of the head to expose the inner hole of the hollow fiber membrane; B. Insert the free end after the first cut of the head into the encapsulating glue for curing, and then take out the free end to obtain the encapsulated free end.

2. The encapsulation method according to claim 1, characterized in that, In step A, after impregnation in the aqueous silicone oil solution, an aqueous silicone oil layer is formed at the free end. After the first cut of the head, the height of the aqueous silicone oil layer is the first height; In step B, the insertion depth into the encapsulating glue is the first depth.

3. The encapsulation method according to claim 2, characterized in that, The first height is greater than the first depth.

4. The encapsulation method according to claim 3, characterized in that, The first height is greater than the first depth by more than 1 cm.

5. The encapsulation method according to any one of claims 2 to 4, characterized in that The first depth is 5 - 20 mm.

6. The encapsulation method according to claim 1, wherein The mass concentration of the aqueous silicone oil solution is 5 - 20%; And / or, the aqueous silicone oil includes at least one of polyether-modified silicone oil, amino-modified silicone oil, carboxyl-modified silicone oil, and hydroxyl-modified silicone oil.

7. The encapsulation method according to claim 1, characterized in that The encapsulating glue includes at least one of epoxy resin glue, polyurethane glue, phenolic resin glue, polyisocyanate glue, polyvinyl acetate glue, polyethylene-vinyl acetate glue, acrylate glue, polystyrene glue, alkyd resin glue, and cellulose glue.

8. A hollow fiber membrane bundle, characterized in that, It is composed of several hollow fiber membrane filaments; The hollow fiber membrane filaments include sealed ends and open ends located at both ends of the filament; The sealed ends are sealed by the encapsulating method described in any one of claims 1 - 7.

9. The hollow fiber membrane bundle according to claim 8, wherein The diameter of the hollow fiber membrane filaments is 0.2 - 5 mm.

10. The hollow fiber membrane bundle according to claim 8, wherein, The material of the hollow fiber membrane filaments includes at least one of polyvinylidene fluoride, polytetrafluoroethylene, polyethersulfone, polysulfone, polypropylene, polyethylene, polyvinyl chloride, polyacrylonitrile, and polyisoprene.

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