Hollow fiber membrane sealant, method for producing the same, and method for sealing a hollow fiber membrane

Abstract

The application provides a hollow fiber membrane sealing agent and a preparation method thereof, and a hollow fiber membrane sealing method. The hollow fiber membrane sealing agent comprises the following raw materials in parts by weight: 50-70 parts of nano calcium carbonate, 2-8 parts of a surfactant, 1-5 parts of a wetting agent, 0.5-3 parts of a defoaming agent, and 25-40 parts of water. In the application, the nano calcium carbonate can be well combined with the surfactant, the wetting agent and the defoaming agent, can be tightly packed in the pores of the hollow fiber membrane filaments, and can form an efficient sealing structure, so as to effectively prevent the pouring sealant from entering the inside of the hollow fiber membrane filaments, ensure the unobstructedness of the pores of the hollow fiber membrane filaments, and make the sealing layer formed by the hollow fiber membrane sealing agent have low hardness and not cause damage to the hollow fiber membrane filaments in the cleaning process, so as to effectively protect the integrity of the hollow fiber membrane filaments. Furthermore, the nano calcium carbonate, the surfactant, the wetting agent, the defoaming agent and water are used as the raw materials of the hollow fiber membrane sealing agent, and the cost is saved.

Description

Technical Field

[0001] This invention relates to the field of hollow fiber membrane technology, specifically to a hollow fiber membrane sealing agent and its preparation method, and a hollow fiber membrane sealing method. Background Technology

[0002] Hollow fiber membrane modules are widely used in water treatment, biomedicine, and chemical separation. A hollow fiber membrane module consists of hollow fiber membrane fibers, potting compound, and a plastic shell. In the manufacturing process of hollow fiber membrane modules, the potting compound injection process is one of the key steps determining its performance. To prevent the potting compound from entering the ports of the hollow fiber membrane fibers during injection and causing blockage of the filtration channels, both ends of the hollow fiber membrane fibers must be sealed before formal potting.

[0003] Currently, there are two common sealing methods. One method uses molding clay as a sealing agent. The molding clay needs to be rolled into thin sheets. Because the molding clay has a relatively high viscosity, the hollow fiber membrane filaments need to be pressed firmly onto the sheet. This places high demands on the strength of the membrane filament bundle itself, easily causing the ends of the smaller diameter hollow fiber membrane filaments to bend and deform, thus failing to seal properly. The other method uses a mixture of water and putty powder or gypsum powder to prepare a sealing material. During operation, this sealing material is applied to the ends of the hollow fiber membrane filaments, and after it dries, a temporary sealing layer is formed. However, the particles of gypsum powder and putty powder do not adhere well and are prone to falling off, resulting in poor sealing. After the sealing fails, the potting compound will penetrate, causing a decrease in the flux of the hollow fiber membrane module, affecting product quality and yield. Summary of the Invention

[0004] In order to at least partially solve the problems existing in the prior art, according to one aspect of the present invention, a hollow fiber membrane sealing agent is provided, the technical solution of which is as follows.

[0005] Hollow fiber membrane sealing agent comprises the following raw materials by weight: 50-70 parts nano calcium carbonate, 2-8 parts surfactant, 1-5 parts wetting agent, 0.5-3 parts defoamer, and 25-40 parts water.

[0006] The hollow fiber membrane sealing agent of this invention utilizes nano-calcium carbonate, which can effectively combine with surfactants, wetting agents, and defoamers. This allows it to densely accumulate within the pores of the hollow fiber membrane fibers, forming a highly efficient sealing structure. This effectively prevents potting compound from entering the interior of the hollow fiber membrane fibers, ensuring unobstructed pores. The surfactant reduces the surface tension of the sealing agent, improving its spreadability and permeability on the hollow fiber membrane surface. The wetting agent enhances the sealing agent's wetting ability on the hollow fiber membrane surface, ensuring uniform sealing. The defoamer effectively inhibits the generation of bubbles during preparation and use. This process avoids air bubbles causing sealing leaks. Water serves as the dispersion medium, and the loose skin structure formed after the hollow fiber membrane sealant dries and cures allows for easy dispersion of the hollow fiber membrane fibers with gentle patting and kneading. No impurities remain on the surface of the hollow fiber membrane fibers, preventing contamination and ensuring the adhesive strength of the potting compound is maintained. The sealing layer formed by the hollow fiber membrane sealant has low hardness, preventing damage to the hollow fiber membrane fibers during removal and effectively protecting their integrity. Furthermore, the use of nano-calcium carbonate, surfactants, wetting agents, defoamers, and water as raw materials for the hollow fiber membrane sealant saves costs.

[0007] For example, the nano-calcium carbonate has a particle size D1, which is 25 nm to 100 nm. This setting ensures dispersibility within the particle size range and facilitates the close packing of nano-calcium carbonate in the pores of the hollow fiber membrane, forming an efficient sealing structure. This effectively prevents the potting compound from entering the interior of the hollow fiber membrane, ensuring the unobstructed pores of the hollow fiber membrane.

[0008] For example, the surfactant is one or more of sodium dodecylbenzenesulfonate, hexadecyltrimethylammonium bromide, fatty alcohol polyoxyethylene ether, and Tween; and / or the wetting agent is one or two of polyether-modified siloxane and dioctyl sodium sulfosuccinate; and / or the defoamer is one of polyether defoamer and organosilicon defoamer; and / or the water is deionized water. With this setup, the surfactant is one or more of sodium dodecylbenzenesulfonate, hexadecyltrimethylammonium bromide, fatty alcohol polyoxyethylene ether, and Tween, which can reduce the surface tension of the hollow fiber membrane sealant and improve its spreadability and permeability on the surface of the hollow fiber membrane fibers; the wetting agent is one or two of polyether-modified siloxane and dioctyl sodium sulfosuccinate, which can enhance the wetting ability of the hollow fiber membrane sealant on the surface of the hollow fiber membrane fibers and ensure uniform sealing; the defoamer is one of polyether defoamers and organosilicon defoamers, which can effectively inhibit the generation of bubbles during preparation and use, and avoid sealing leaks caused by bubbles; the water is deionized water, which can act as a dispersion medium. The skin structure formed after the hollow fiber membrane sealant dries and cures is loose, and the hollow fiber membrane fibers can be dispersed by gently patting and kneading, without leaving impurities on the surface of the hollow fiber membrane fibers, thus avoiding contamination of the hollow fiber membrane fiber surface and affecting the bonding strength of the potting compound.

[0009] According to another aspect of the present invention, a method for preparing a hollow fiber membrane sealing agent is provided, comprising the following steps: pretreatment of nano-calcium carbonate; mixing and initially dispersing a measured amount of water, surfactant, wetting agent, and defoamer to obtain a uniform mixed solution; weighing a measured amount of pretreated nano-calcium carbonate and adding it to the mixed solution, and dispersing it at high speed for a predetermined first time; then adding a measured amount of defoamer and dispersing it again for a predetermined second time before filtration, to obtain the hollow fiber membrane sealing agent as described above. In this method, the pretreatment of nano-calcium carbonate ensures its full dispersion and prevents agglomeration; the weighing and addition of a measured amount of pretreated nano-calcium carbonate to the mixed solution and high-speed dispersion for a predetermined first time allows the nano-calcium carbonate to combine well with the surfactant, wetting agent, and defoamer, ensuring its full dispersion, effectively preventing agglomeration, and effectively suppressing the generation of bubbles during the preparation process; the addition of a measured amount of defoamer and dispersing it again for a predetermined second time before filtration further suppresses the generation of bubbles during the preparation process and further removes any potentially agglomerated particles; furthermore, the entire preparation process does not require complex equipment or stringent process conditions, making it suitable for large-scale industrial production and effectively improving production efficiency.

[0010] For example, the initial dispersion is achieved by stirring with a stirrer at a speed of 300 rpm to 500 rpm for 1 to 15 minutes. This setup ensures that water, surfactant, wetting agent, and defoamer are mixed evenly, and the stirring with a stirrer effectively improves production efficiency.

[0011] For example, high-speed dispersion is achieved by stirring with a stirrer at a speed of 800 rpm to 1200 rpm for 10 to 45 minutes. This setup not only ensures thorough dispersion of nano-calcium carbonate and effectively prevents agglomeration, but also significantly improves production efficiency through stirring.

[0012] For example, redispersion is performed by stirring with a stirrer at a speed of 300 rpm to 500 rpm for 5 to 10 minutes. This setting ensures that the defoamer is fully mixed, effectively suppressing the generation of bubbles during preparation and use, and preventing blockages caused by bubbles.

[0013] For example, the pretreatment step for nano-calcium carbonate includes: coupling activation treatment; and drying in a drying oven at a temperature of 80°C to 120°C for 2 to 4 hours. This setup ensures that the coupling activation treatment fully disperses the nano-calcium carbonate and prevents agglomeration; drying the nano-calcium carbonate further fully disperses it and prevents agglomeration.

[0014] For example, in the step of adding a metered amount of defoamer and redispersing for a predetermined second time before filtration to obtain the hollow fiber membrane sealant, the sealant is filtered through a 100-200 mesh filter and then sealed and stored in a cool, dry place at a temperature of 5°C to 30°C. This arrangement, on the one hand, removes any potentially agglomerated particles through filtration through a 100-200 mesh filter; on the other hand, sealing and storing in a cool, dry place at a temperature of 5°C to 30°C effectively prevents moisture evaporation, microbial contamination, and high-temperature-induced agglomeration or degradation, ensuring the functionality of the hollow fiber membrane sealant for future use.

[0015] According to another aspect of the present invention, a method for sealing a hollow fiber membrane is provided, comprising the following steps: applying or impregnating the hollow fiber membrane bundle with the hollow fiber membrane sealing agent as described above; performing a drying and curing treatment; performing a potting compound potting operation; and removing excess potting compound after potting to remove the blockage. The hollow fiber membrane sealing method of the present invention, through the hollow fiber membrane sealing agent, can tightly accumulate in the pores of the hollow fiber membrane filaments to form a highly efficient sealing structure, thereby effectively preventing the potting compound from entering the interior of the hollow fiber membrane filaments. After the removal operation, it ensures that the pores of the hollow fiber membrane filaments are unobstructed, and the operation is simple, improving production efficiency.

[0016] For example, in the step of impregnating the hollow fiber membrane bundle with the hollow fiber membrane sealing agent, the impregnation depth is 2mm~3mm and the impregnation time is 1min~2min. This setting effectively ensures that the hollow fiber membrane sealing agent enters the pores of the hollow fiber membrane and packs tightly.

[0017] For example, in the drying and curing step, the sealed hollow fiber membrane filaments are placed in a ventilated area and dried at room temperature for 1 to 4 hours, or blown with hot air at 30°C to 50°C for 10 to 30 minutes. This setup allows the hollow fiber membrane sealant, which is dried and cured in the pores of the hollow fiber membrane filaments, to form a highly efficient sealing structure. This effectively prevents the potting compound from entering the interior of the hollow fiber membrane filaments, ensuring the pores of the hollow fiber membrane filaments remain open after the cutting operation.

[0018] A series of simplified concepts are introduced in the description of the invention, which will be further explained in detail in the detailed description section. This description is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0019] The advantages and features of the present invention will be described in detail below with reference to the accompanying drawings. Attached Figure Description

[0020] The following figures are included as part of this invention for understanding its principles. The figures illustrate embodiments of the invention and their descriptions, serving to explain the principles of the invention. In the figures,

[0021] Figure 1 This is a schematic diagram of the structure of a hollow fiber membrane sealing agent used to seal hollow fiber membrane filaments, which is an exemplary embodiment of the present invention.

[0022] The above figures include the following reference numerals:

[0023] 10. Hollow fiber membrane sealing agent; 20. Hollow fiber membrane filaments. Detailed Implementation

[0024] In the following description, numerous details are provided to enable a thorough understanding of the invention. However, those skilled in the art will appreciate that the following description merely illustrates preferred embodiments of the invention, and that the invention can be practiced without one or more of these details. Furthermore, to avoid obscuring the invention, some technical features well-known in the art have not been described in detail.

[0025] To fully understand the embodiments of the present invention, detailed structures will be presented in the following description. Obviously, the implementation of the embodiments of the present invention is not limited to the specific details familiar to those skilled in the art. Preferred embodiments of the present invention are described in detail below; however, in addition to these detailed descriptions, the present invention may have other embodiments.

[0026] This invention provides a hollow fiber membrane sealing agent. The hollow fiber membrane sealing agent of this invention can be used to seal hollow fiber membrane filaments. The hollow fiber membrane sealing agent of this invention can be prepared by a hollow fiber membrane sealing agent preparation method. The hollow fiber membrane sealing agent of this invention can be used to seal hollow fiber membrane filaments by a hollow fiber membrane sealing method. The following will describe in detail, with reference to the accompanying drawings, a hollow fiber membrane sealing agent according to an embodiment of this invention.

[0027] See Figure 1 The hollow fiber membrane sealing agent 10 may include the following raw materials by weight: 50-70 parts of nano-calcium carbonate, 2-8 parts of surfactant, 1-5 parts of wetting agent, 0.5-3 parts of defoamer, and 25-40 parts of water. Specifically, the weight of nano-calcium carbonate may be 50, 60, or 70 parts, etc. The weight of surfactant may be 2, 2.5, or 8 parts, etc. The weight of wetting agent may be 1, 3, or 5 parts, etc. The weight of defoamer may be 0.5, 1.5, or 3 parts, etc. The weight of water may be 25, 28, or 40 parts, etc.

[0028] The hollow fiber membrane sealing agent 10 of this invention utilizes nano-calcium carbonate, which can effectively combine with surfactants, wetting agents, and defoamers. It can densely accumulate within the pores of the hollow fiber membrane filaments 20, forming a highly efficient sealing structure. This effectively prevents potting compound from entering the interior of the hollow fiber membrane filaments 20, ensuring unobstructed pores. The surfactant reduces the surface tension of the hollow fiber membrane sealing agent 10, improving its spreadability and permeability on the surface of the hollow fiber membrane filaments 20. The wetting agent enhances the wetting ability of the hollow fiber membrane sealing agent 10 on the surface of the hollow fiber membrane filaments 20, ensuring uniform sealing. The defoamer effectively inhibits the generation of bubbles during preparation and use. This avoids air bubbles causing sealing leaks; water serves as the dispersion medium, and the loose skin structure formed after the hollow fiber membrane sealant 10 dries and cures allows for easy dispersion of the hollow fiber membrane fibers 20 with gentle patting and kneading, without leaving any impurities on the surface of the hollow fiber membrane fibers 20, thus avoiding contamination of the surface of the hollow fiber membrane fibers 20 and affecting the bonding strength of the potting compound; the sealing layer formed by the hollow fiber membrane sealant 10 has low hardness, and will not damage the hollow fiber membrane fibers 20 during the removal process, effectively protecting the integrity of the hollow fiber membrane fibers 20, and saving costs by using nano-calcium carbonate, surfactants, wetting agents, defoamers and water as raw materials for the hollow fiber membrane sealant 10.

[0029] For example, the nano-calcium carbonate can have a particle size D1, which can be 25 nm to 100 nm, such as 25 nm, 60 nm, 80 nm, or 100 nm. This particle size range ensures dispersibility and facilitates the tight packing of nano-calcium carbonate within the pores of the hollow fiber membrane filaments 20, forming an efficient sealing structure. This effectively prevents the potting compound from entering the interior of the hollow fiber membrane filaments 20, ensuring the unobstructed pores of the hollow fiber membrane filaments 20. Preferably, the particle size D1 can be 60 nm to 80 nm, such as 60 nm, 65 nm, 70 nm, or 80 nm. When the particle size D1 is within this range, not only is the sealing effect guaranteed, but the dispersion effect is also improved.

[0030] For example, the surfactant can be one or more of sodium dodecylbenzenesulfonate, hexadecyltrimethylammonium bromide, fatty alcohol polyoxyethylene ether, and Tween. This reduces the surface tension of the hollow fiber membrane sealant 10, improving its spreadability and permeability on the surface of the hollow fiber membrane filaments 20.

[0031] For example, the wetting agent can be one or both of polyether-modified siloxane and sodium dioctyl sulfosuccinate. This enhances the wetting ability of the hollow fiber membrane sealant 10 on the surface of the hollow fiber membrane filaments 20, ensuring uniform sealing.

[0032] For example, the defoamer can be one of a polyether defoamer or an organosilicon defoamer. This effectively suppresses the generation of bubbles during preparation and use, preventing blockages caused by bubbles.

[0033] For example, the water can be deionized water. In this way, water can serve as a dispersion medium. The skin structure formed after the hollow fiber membrane sealant 10 dries and cures is loose. The hollow fiber membrane filaments 20 can be dispersed by gently patting and kneading, and no impurities will remain on the surface of the hollow fiber membrane filaments 20, thus avoiding contamination of the surface of the hollow fiber membrane filaments 20 and affecting the bonding strength of the potting compound.

[0034] According to another aspect of the present invention, a method for preparing a hollow fiber membrane sealing agent is provided. The method may include the following steps: pretreatment of nano-calcium carbonate; mixing measured amounts of water, surfactant, wetting agent, and defoamer and initially dispersing to obtain a uniform mixed solution; weighing measured amounts of pretreated nano-calcium carbonate and adding it to the mixed solution, dispersing at high speed for a predetermined first time, then adding measured amounts of defoamer and dispersing again for a predetermined second time, followed by filtration to obtain the hollow fiber membrane sealing agent 10 as described above. Specifically, a stirrer can be used for stirring in the initial dispersion, high-speed dispersion, and re-dispersion steps to achieve precise dispersion. Of course, manual stirring is also possible to suit various scenarios.

[0035] The hollow fiber membrane sealing agent preparation method of the present invention, on the one hand, involves pretreatment of nano-calcium carbonate to ensure its full dispersion and prevent agglomeration; weighing a measured amount of pretreated nano-calcium carbonate and adding it to a mixed solution, then dispersing it at high speed for a predetermined first time, allowing the nano-calcium carbonate to combine well with surfactants, wetting agents, and defoamers, ensuring its full dispersion, effectively preventing agglomeration, and effectively suppressing the generation of bubbles during the preparation process; adding a measured amount of defoamer and dispersing it again for a predetermined second time before filtration, further suppressing the generation of bubbles during the preparation process, and further removing any potentially agglomerated particles; on the other hand, the entire preparation process does not require complex equipment or harsh process conditions, making it suitable for large-scale industrial production and effectively improving production efficiency.

[0036] For example, initial dispersion can be achieved by stirring with a stirrer at a speed of 300 rpm to 500 rpm for 1 to 15 minutes. Specifically, the stirrer speed during initial dispersion can be 300 rpm, 350 rpm, 400 rpm, or 500 rpm, etc. The stirring time can be 1 minute, 5 minutes, 10 minutes, or 15 minutes, etc. In this way, water, surfactant, wetting agent, and defoamer can be mixed evenly, and stirring with a stirrer can effectively improve production efficiency.

[0037] For example, high-speed dispersion can be achieved by stirring with a stirrer at a speed of 800 rpm to 1200 rpm for 10 min to 45 min. Understandably, the predetermined initial time can be 10 min to 45 min. Specifically, the stirrer speed during high-speed dispersion can be 800 rpm, 1000 rpm, 1100 rpm, or 1200 rpm, etc. The predetermined initial time can be 10 min, 30 min, 40 min, or 45 min, etc. This not only ensures thorough dispersion of nano-calcium carbonate, effectively preventing agglomeration, but also significantly improves production efficiency through stirring.

[0038] For example, redispersion can be performed by stirring with a stirrer at a speed of 300 rpm to 500 rpm for 5 to 10 minutes. Understandably, the predetermined second time can be 5 to 10 minutes. Specifically, the stirrer speed during redispersion can be 300 rpm, 350 rpm, 400 rpm, or 500 rpm, etc. The predetermined second time can be 5 minutes, 7 minutes, 8 minutes, or 10 minutes, etc. This ensures thorough mixing of the defoamer, effectively suppressing the generation of bubbles during preparation and use, and preventing blockages caused by bubbles.

[0039] For example, the pretreatment step for nano-calcium carbonate may include: coupling activation treatment; and drying in a drying oven at a temperature of 80℃~120℃ for 2h~4h. Specifically, the coupling activation treatment can be performed by treating the nano-calcium carbonate with a coupling agent to ensure sufficient dispersion. The drying temperature of the drying oven for nano-calcium carbonate can be 80℃, 105℃, or 120℃, etc., and the drying time can be 2h, 3h, or 4h, etc. In this way, the coupling activation treatment ensures sufficient dispersion of the nano-calcium carbonate and avoids agglomeration; drying the nano-calcium carbonate further ensures sufficient dispersion and avoids agglomeration. Of course, the pretreatment step for nano-calcium carbonate may also simply include drying in a drying oven at a temperature of 80℃~120℃ for 2h~4h to suit various scenarios.

[0040] For example, in the step of adding a metered amount of defoamer and redispersing for a predetermined second time to obtain hollow fiber membrane sealant 10, the mixture is filtered through a 100-200 mesh filter and then sealed and stored in a cool, dry place at a temperature of 5°C to 30°C. Specifically, the filter can be 100 mesh, 150 mesh, or 200 mesh. The sealed storage temperature of the hollow fiber membrane sealant 10 can be 5°C, 15°C, or 30°C, etc. In this way, on the one hand, filtration through a 100-200 mesh filter can remove any potentially agglomerated particles; on the other hand, sealing and storing in a cool, dry place at a temperature of 5°C to 30°C effectively prevents moisture evaporation, microbial contamination, high-temperature-induced agglomeration or degradation, ensuring the functionality of the hollow fiber membrane sealant 10 for the next use.

[0041] In one embodiment of the present invention, the method for preparing a hollow fiber membrane sealing agent includes the following steps:

[0042] S1. Pretreatment of nano-calcium carbonate: The measured nano-calcium carbonate is coupled and activated, and then placed in a drying oven and dried at 80℃~120℃ for 2h~4h to remove surface adsorbed moisture, and then set aside for use; or the measured nano-calcium carbonate is placed in a drying oven and dried at 80℃~120℃ for 2h~4h to remove surface adsorbed moisture, and then set aside for use.

[0043] S2. Initial dispersion: Add the measured amount of deionized water to the stirring container, turn on the stirrer, and control the speed at 300 r / min to 500 r / min. Add the measured amount of surfactant, wetting agent, and defoamer to the stirrer and stir for 1 min to 15 min to completely dissolve the surfactant, wetting agent, and defoamer in the water to obtain a uniform mixed solution.

[0044] S3. High-speed dispersion: The pretreated nano-calcium carbonate is slowly added to the uniform mixed solution obtained in the initial dispersion step, while the stirring speed is increased to 800 r / min~1200 r / min, and the stirring time is set to 10 min~45 min.

[0045] S4. Redispersion: Reduce the stirrer speed to 300r / min~500r / min, add the metered defoamer, stir for the second time of 5min~10min, and obtain a uniform hollow fiber membrane sealing agent 10.

[0046] S5. Filtration and storage: Filter the prepared hollow fiber membrane sealing agent 10 through a 100-200 mesh filter, then seal and store it in a cool, dry place at a temperature of 5℃ to 30℃.

[0047] Thus, on the one hand, nano-calcium carbonate can be fully dispersed to avoid agglomeration, and it can combine well with surfactants, wetting agents, and defoamers. At the same time, it can effectively suppress the generation of bubbles during the preparation process. On the other hand, the entire preparation process does not require complex equipment or harsh process conditions, making it suitable for large-scale industrial production and effectively improving production efficiency.

[0048] According to another aspect of the present invention, a method for sealing hollow fiber membranes is provided, see reference. Figure 1 The hollow fiber membrane sealing method may include the following steps: applying or impregnating the hollow fiber membrane bundle with the hollow fiber membrane sealing agent 10 as described above; performing a drying and curing process; performing a potting compound potting operation; and removing excess potting compound to remove the sealant. Specifically, when applying the hollow fiber membrane sealing agent 10 to the membrane bundle's ends, an appropriate amount of the hollow fiber membrane sealing agent 10 can be applied using a cutter to ensure that the hollow fiber membrane sealing agent 10 fully penetrates the hollow fiber membrane filaments 20 to form a sealing layer. The potting compound can be a resin adhesive or epoxy resin adhesive, etc., for use in various scenarios.

[0049] The hollow fiber membrane sealing method of the present invention uses a hollow fiber membrane sealing agent 10 to tightly accumulate in the pores of the hollow fiber membrane filaments 20, forming a highly efficient sealing structure. This effectively prevents the potting compound from entering the interior of the hollow fiber membrane filaments 20. After the cutting operation, it ensures that the pores of the hollow fiber membrane filaments 20 are unobstructed. The method is simple to operate and improves production efficiency.

[0050] For example, in the step of impregnating the hollow fiber membrane bundle with the hollow fiber membrane sealing agent 10, the impregnation depth can be 2mm to 3mm, and the impregnation time can be 1min to 2min. Specifically, the impregnation depth can be 2mm, 2.5mm, or 3mm, etc., and the impregnation time can be 1min, 1.5min, or 2min, etc. In this way, it is effectively ensured that the hollow fiber membrane sealing agent 10 enters the channels of the hollow fiber membrane filaments 20 and is tightly packed.

[0051] For example, in the drying and curing step, the hollow fiber membrane filament 20 with the sealed port is placed in a ventilated area; it is dried at room temperature for 1 to 4 hours, or purged with hot air at 30°C to 50°C for 10 to 30 minutes. Specifically, when drying at room temperature, the drying time can be 1 hour, 3 hours, or 4 hours, etc. When purging with hot air, the hot air temperature can be 30°C, 40°C, or 50°C, etc., and the purging time can be 10 minutes, 20 minutes, or 30 minutes. In this way, by drying and curing the hollow fiber membrane sealant 10 in the pores of the hollow fiber membrane filament 20, the hollow fiber membrane sealant 10 forms a highly efficient sealing structure, thereby effectively preventing the potting compound from entering the interior of the hollow fiber membrane filament 20, ensuring that the pores of the hollow fiber membrane filament 20 are unobstructed after the cutting operation.

[0052] For example, the steps before applying or impregnating the hollow fiber membrane bundle with the hollow fiber membrane sealant 10 include: arranging multiple hollow fiber membrane filaments 20 in parallel, cutting them to form a hollow fiber membrane bundle with flush ends, and removing impurities from the surface of the hollow fiber membrane filaments 20. Specifically, a utility knife can be used to cut the hollow fiber membrane bundle to ensure neatness and safety. This facilitates the sealing of the membrane ends of the hollow fiber membrane bundle by the hollow fiber membrane sealant 10.

[0053] For example, in the process of potting with potting compound and then removing excess potting compound to remove the sealant, the sealed hollow fiber membrane bundles are gently kneaded to loosen the bonded hollow fiber membrane filaments 20. The residual hollow fiber membrane sealant 10 on the outer surface of the hollow fiber membrane filaments 20 is then gently tapped away. The hollow fiber membrane bundles are then placed in the housing and potting compound is poured in. After the potting compound cures, excess potting compound is removed from the hollow fiber membrane bundles at a height of 10mm to 12mm to remove the sealant and allow the hollow fiber membrane filaments 20 to conduct, resulting in a potted hollow fiber membrane module. It should be noted that mechanical cutting can be used to remove excess potting compound from the hollow fiber membrane bundles for precise removal. Manual cutting is also an option to suit various scenarios. The removal height can be 10mm, 11mm, or 12mm, etc., to ensure that the hollow fiber membrane filaments 20 remain conductive after removal. In this way, the membrane fiber port is sealed by the hollow fiber membrane sealing agent 10. The potting adhesive will not flow into the hollow fiber membrane fiber 20, but will only permeate and flow between the hollow fiber membrane fibers 20. The cured potting adhesive plays the role of bonding the hollow fiber membrane fiber 20 and the shell. Moreover, the cut-off height is within this range, which can effectively remove the blockage and make the hollow fiber membrane fiber 20 conductive.

[0054] In one embodiment of the present invention, the hollow fiber membrane sealing method includes the following steps:

[0055] S1. Hollow fiber membrane bundle pretreatment: Arrange multiple hollow fiber membrane filaments 20 in parallel, bundle them together, cut them, and form hollow fiber membrane bundles with flush ends to remove impurities from the surface of hollow fiber membrane filaments 20.

[0056] S2. Sealing operation: Apply an appropriate amount of hollow fiber membrane sealing agent 10 to the ends of the neatly cut hollow fiber membrane filaments 20, ensuring that the hollow fiber membrane sealing agent 10 fully enters the hollow fiber membrane filaments 20 to form a sealing layer; or immerse the hollow fiber membrane filament bundle in the hollow fiber membrane sealing agent 10, with an immersion depth of 2mm~3mm and an immersion time of 1min~2min, and then remove the immersed hollow fiber membrane filament bundle.

[0057] S3. Drying and curing: Place the sealed hollow fiber membrane bundle in a ventilated place and dry it at room temperature for 1 to 4 hours, or blow it with hot air at 30°C to 50°C for 10 to 30 minutes to evaporate the moisture in the hollow fiber membrane sealing agent 10 and allow components such as nano-calcium carbonate to accumulate and form a stable sealing structure.

[0058] S4. Encapsulation and Removal: Gently knead the sealed hollow fiber membrane bundle to loosen the bonded hollow fiber membrane filaments 20. Lightly tap to remove the residual hollow fiber membrane sealant 10 on the outer surface of the hollow fiber membrane filaments 20. Then, place the hollow fiber membrane bundle into the shell and inject the encapsulating adhesive. After the encapsulating adhesive has cured, remove the excess encapsulating adhesive from the hollow fiber membrane bundle. The removal height is 10mm~12mm. Remove the sealant to make the hollow fiber membrane filaments 20 conductive, and obtain the finished hollow fiber membrane module with encapsulation.

[0059] In this way, the hollow fiber membrane sealing agent 10 can be tightly packed in the pores of the hollow fiber membrane filament 20 to form an efficient sealing structure, thereby effectively preventing the potting compound from entering the interior of the hollow fiber membrane filament 20. After the cutting operation, it can ensure that the pores of the hollow fiber membrane filament 20 are unobstructed, and the operation is simple, thus improving production efficiency.

[0060] Example 1

[0061] Hollow fiber membrane sealing agent 10 comprises the following raw materials in parts by weight: 60 parts of nano calcium carbonate, 3 parts of fatty alcohol polyoxyethylene ether, 1 part of sodium dioctyl sulfosuccinate, 0.5 parts of silicone defoamer, and 25 parts of deionized water.

[0062] The method for preparing a hollow fiber membrane sealing agent based on the above-mentioned raw materials in parts by weight includes the following steps:

[0063] S1. Pretreatment of nano-calcium carbonate: Place 60 parts of nano-calcium carbonate in a drying oven and dry at 105℃ for 3 hours to remove surface adsorbed moisture and set aside for later use.

[0064] S2. Initial dispersion: Add 25 parts of deionized water to the mixing container, turn on the stirrer and control the speed at 400 r / min. Add 3 parts of fatty alcohol polyoxyethylene ether, 1 part of sodium dioctyl sulfosuccinate, and 0.25 parts of silicone defoamer to the stirrer and stir for 8 minutes to completely dissolve the fatty alcohol polyoxyethylene ether, sodium dioctyl sulfosuccinate, and silicone defoamer in the water to obtain a uniform mixed solution.

[0065] S3. High-speed dispersion: The pretreated nano-calcium carbonate is slowly added to the uniform mixed solution obtained in the initial dispersion step, while the stirring speed is increased to 1000 r / min and the stirring time is set to 30 min.

[0066] S4. Redispersion: Reduce the stirrer speed to 400 r / min, add 0.25 parts of defoamer, stir for the second time of 8 min, and obtain a uniform hollow fiber membrane sealing agent 10.

[0067] S5. Filtration and storage: Filter the prepared hollow fiber membrane sealing agent 10 through a 150-mesh filter, and then seal and store it in a cool and dry place.

[0068] Hollow fiber membrane sealing agent 10 prepared using the above preparation method, and hollow fiber membrane sealing method, include the following steps:

[0069] S1. Hollow fiber membrane bundle pretreatment: Arrange multiple hollow fiber membrane filaments 20 in parallel, bundle them together, cut them, and form hollow fiber membrane bundles with flush ends to remove impurities from the surface of hollow fiber membrane filaments 20.

[0070] S2. Sealing operation: Immerse the hollow fiber membrane bundle in the hollow fiber membrane sealing agent 10. The immersion depth can be 3mm and the immersion time can be 2min. Take out the immersed hollow fiber membrane bundle.

[0071] S3. Drying and curing: Place the sealed hollow fiber membrane bundle in a ventilated place and dry at room temperature for 3 hours;

[0072] S4. Encapsulation and Removal: Gently knead the sealed hollow fiber membrane bundle to loosen the bonded hollow fiber membrane filaments 20. Gently tap to remove the residual hollow fiber membrane sealant 10 on the outer surface of the hollow fiber membrane filaments 20. Then, place the hollow fiber membrane bundle into the shell and inject the encapsulating adhesive. After the encapsulating adhesive has cured, remove the excess encapsulating adhesive from the hollow fiber membrane bundle. The removal height is 10mm. Remove the sealant to allow the membrane filaments to conduct, and obtain the finished hollow fiber membrane module with encapsulation.

[0073] Example 2

[0074] Hollow fiber membrane sealing agent 10 comprises the following raw materials in parts by weight: 50 parts of nano calcium carbonate, 2.5 parts of sodium dodecylbenzene sulfonate, 1 part of polyether modified siloxane, 0.5 parts of organosilicon defoamer, and 28 parts of deionized water.

[0075] The method for preparing hollow fiber membrane sealing agent 10 based on the above-mentioned raw materials in parts by weight includes the following steps:

[0076] S1. Pretreatment of nano-calcium carbonate: 50 parts of nano-calcium carbonate were coupled and activated, and 50 parts of nano-calcium carbonate were placed in a drying oven and dried at 105℃ for 3 hours to remove surface adsorbed moisture and set aside for later use.

[0077] S2. Initial dispersion: Add 28 parts of deionized water to the mixing container, turn on the stirrer and control the speed at 400 r / min. Add 1.5 parts of sodium dodecylbenzenesulfonate, 1 part of polyether modified siloxane, and 0.25 parts of organosilicon defoamer to the stirrer and stir for 10 min to completely dissolve the sodium dodecylbenzenesulfonate, polyether modified siloxane, and organosilicon defoamer in the water to obtain a uniform mixed solution.

[0078] S3. High-speed dispersion: The pretreated nano-calcium carbonate is slowly added to the uniform mixed solution obtained in the initial dispersion step, while the stirring speed is increased to 1000 r / min and the stirring time is set to 30 min.

[0079] S4. Redispersion: Reduce the stirrer speed to 400 r / min, add 0.25 parts of defoamer, stir for a second time of 5 min, and obtain a uniform hollow fiber membrane sealing agent 10.

[0080] S5. Filtration and storage: Filter the prepared hollow fiber membrane sealing agent 10 through a 150-mesh filter, and then seal and store it in a cool and dry place.

[0081] Hollow fiber membrane sealing agent 10 prepared using the above preparation method, and hollow fiber membrane sealing method, include the following steps:

[0082] S1. Hollow fiber membrane bundle pretreatment: Arrange multiple hollow fiber membrane filaments 20 in parallel, bundle them together, cut them, and form hollow fiber membrane bundles with flush ends to remove impurities from the surface of hollow fiber membrane filaments 20.

[0083] S2. Sealing operation: Apply an appropriate amount of hollow fiber membrane sealing agent 10 to the ends of the neatly cut hollow fiber membrane filaments 20, ensuring that the hollow fiber membrane sealing agent 10 fully enters the hollow fiber membrane filaments 20 to form a sealing layer.

[0084] S3. Drying and curing: Blow with hot air at 50℃ for 30 minutes;

[0085] S4. Encapsulation and Removal: Gently knead the sealed hollow fiber membrane bundle to loosen the bonded hollow fiber membrane filaments 20. Gently tap to remove the residual hollow fiber membrane sealant 10 on the outer surface of the hollow fiber membrane filaments 20. Then, place the hollow fiber membrane bundle into the shell and inject the encapsulating adhesive. After the encapsulating adhesive has cured, remove the excess encapsulating adhesive from the hollow fiber membrane bundle. The removal height is 10mm. Remove the sealant to make the hollow fiber membrane filaments 20 conductive, and obtain the finished hollow fiber membrane module with encapsulation.

[0086] Example 3

[0087] Hollow fiber membrane sealing agent 10 comprises the following raw materials in parts by weight: 70 parts of nano calcium carbonate, 2 parts of fatty alcohol polyoxyethylene ether, 1 part of sodium dioctyl sulfosuccinate, 0.5 parts of silicone defoamer, and 28 parts of deionized water.

[0088] The method for preparing a hollow fiber membrane sealing agent based on the above-mentioned raw materials in parts by weight includes the following steps:

[0089] S1. Pretreatment of nano-calcium carbonate: Place 70 parts of nano-calcium carbonate in a drying oven and dry at 105℃ for 3 hours to remove surface adsorbed moisture and set aside for later use.

[0090] S2. Initial dispersion: Add 28 parts of deionized water to the mixing container, turn on the stirrer and control the speed at 400 r / min. Add 2 parts of fatty alcohol polyoxyethylene ether, 1 part of sodium dioctyl sulfosuccinate, and 0.25 parts of organosilicon defoamer to the stirrer and stir for 5 min to completely dissolve the fatty alcohol polyoxyethylene ether, sodium dioctyl sulfosuccinate, and organosilicon defoamer in the water to obtain a uniform mixed solution.

[0091] S3. High-speed dispersion: The pretreated nano-calcium carbonate is slowly added to the uniform mixed solution obtained in the initial dispersion step, while the stirring speed is increased to 1000 r / min and the stirring time is set to 40 min.

[0092] S4. Redispersion: Reduce the stirrer speed to 400 r / min, add 0.25 parts of defoamer, stir for the second time of 8 min, and obtain a uniform hollow fiber membrane sealing agent 10.

[0093] S5. Filtration and storage: Filter the prepared hollow fiber membrane sealing agent 10 through a 150-mesh filter, and then seal and store it in a cool and dry place.

[0094] Hollow fiber membrane sealing agent 10 prepared using the above preparation method, and hollow fiber membrane sealing method, include the following steps:

[0095] S1. Hollow fiber membrane bundle pretreatment: Arrange multiple hollow fiber membrane filaments 20 in parallel, bundle them together, cut them, and form hollow fiber membrane bundles with flush ends to remove impurities from the surface of hollow fiber membrane filaments 20.

[0096] S2. Sealing operation: Immerse the hollow fiber membrane bundle in the hollow fiber membrane sealing agent 10. The immersion depth can be 3mm and the immersion time can be 2min. Take out the immersed hollow fiber membrane bundle.

[0097] S3. Drying and curing: Blow with hot air at 50℃ for 20 minutes;

[0098] S4. Encapsulation and Removal: Gently knead the sealed hollow fiber membrane bundle to loosen the bonded hollow fiber membrane filaments 20. Gently tap to remove the residual hollow fiber membrane sealant 10 on the outer surface of the hollow fiber membrane filaments 20. Then, place the hollow fiber membrane bundle into the shell and inject the encapsulating adhesive. After the encapsulating adhesive has cured, remove the excess encapsulating adhesive from the hollow fiber membrane bundle. The removal height is 10mm. Remove the sealant to make the hollow fiber membrane filaments 20 conductive, and obtain the finished hollow fiber membrane module with encapsulation.

[0099] Comparative Example 1

[0100] The hollow fiber membrane sealing agent uses ultra-light clay as raw material. First, the ultra-light clay is rolled into a thin sheet with a thickness of 0.5 mm. Then, multiple hollow fiber membrane filaments 20 are arranged neatly and bundled into a hollow fiber membrane filament bundle. The ends of the hollow fiber membrane filaments 20 are cut flat. Then, the ends of the hollow fiber membrane filament bundle are pressed firmly onto the clay sheet to seal it. Remove the clay adhering to the outer wall of the hollow fiber membrane filaments 20 and air dry for 3 hours under ventilated and dry conditions. Then, potting compound (such as resin glue) is applied. After curing, the excess potting compound is cut off at a height of 10 mm to remove the blockage and make the hollow fiber membrane filaments 20 conductive.

[0101] Comparative Example 2

[0102] The hollow fiber membrane sealing agent uses putty powder and water as raw materials, with the powder and water mixed in a 2:1 ratio. Multiple hollow fiber membrane filaments 20 are arranged neatly and bundled into a hollow fiber membrane filament bundle. The ends of the hollow fiber membrane filaments 20 are cut flat. An appropriate amount of hollow fiber membrane sealing agent is applied to the cut ends of the hollow fiber membrane filaments 20. The bundle is then blown with hot air at 50°C for 30 minutes and potted with a potting compound (such as epoxy resin). After curing, excess potting compound is removed at a height of 10 mm to remove the blockage and allow the hollow fiber membrane filaments 20 to conduct.

[0103] The sealing effect of Examples 1-3 and Comparative Examples 1 and 2 was tested. The testing methods could include visual inspection or testing the gas flow rate, etc. The test results of the sealing effect of Examples 1-3 and Comparative Examples 1 and 2 are shown in the table below:

[0104]

[0105] Using Examples 1, 2, and 3, along with Comparative Example 1, as a control group, Examples 1, 2, and 3 all achieved a 100% porosity (i.e., the pores of the cut hollow fiber membrane filaments 20 were unobstructed, with no residue of the hollow fiber membrane sealing agent 10). In contrast, Comparative Example 1 had a porosity of 95%, which was lower. Furthermore, the sealing height of Comparative Example 1 was significantly lower than that of Examples 1, 2, and 3. It should be noted that in Comparative Example 1, the high viscosity of the clay resulted in a lower sealing height of the hollow fiber membrane sealing agent. During potting, the potting adhesive was prone to breaking through the sealing layer, and the hollow fiber membrane filaments 20 were also prone to deformation, failing to completely seal, ultimately leading to a lower porosity. Therefore, Examples 1, 2, and 3 exhibit better sealing effects, are simple to operate, easy to remove, have short drying times, and save costs.

[0106] Using Examples 1, 2, and 3, along with Comparative Example 2, as a control group, Examples 1, 2, and 3 all achieved a 100% porosity (i.e., the pores of the cut hollow fiber membrane filaments 20 were unobstructed, with no hollow fiber membrane sealing agent 10 residue). In contrast, Comparative Example 1 had a low porosity of 81%, and the sealing height of Comparative Example 2 was significantly lower than that of Examples 1, 2, and 3. It should be noted that in Comparative Example 2, the putty powder particles had a relatively large mesh size, resulting in low sealing efficiency after the hollow fiber membrane sealing agent cured. Furthermore, because only water was used as a diluent, the wettability was poor, making it difficult for the putty powder particles to adhere to the surface of the hollow fiber membrane filaments 20. This made it easy for the hollow fiber membrane sealing agent to detach during the dispersion process, ultimately leading to poor sealing performance. Therefore, Examples 1, 2, and 3 exhibit better sealing effects, are simple to operate, easy to remove, have short drying times, and save costs.

[0107] In addition, using Examples 1 and 3 as control groups, both Examples 1 and 3 achieved a 100% opening rate and exhibited good sealing effects. The sealing height of Example 1 was higher than that of Example 3. Since the amount of surfactant used in Examples 1 and 3 differed, the amount of surfactant slightly affected the sealing height. Comparing Example 1 with Examples 2 and 3, the drying method of the hollow fiber membrane sealing agent 10 in Example 1 differed from that in Examples 2 and 3. Examples 2 and 3 used hot air drying, which significantly shortened the drying time and improved work efficiency.

[0108] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, parts, components, and / or combinations thereof.

[0109] The present invention has been described through the above embodiments. However, it should be understood that the above embodiments are for illustrative purposes only and are not intended to limit the invention to the scope of the described embodiments. Furthermore, those skilled in the art will understand that the present invention is not limited to the above embodiments, and many more variations and modifications can be made based on the teachings of the present invention, all of which fall within the scope of protection claimed by the present invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A hollow fiber membrane sealing agent, characterized in that, The hollow fiber membrane sealing agent comprises the following raw materials in parts by weight: 50-70 parts of nano calcium carbonate, 2-8 parts of surfactant, 1-5 parts of wetting agent, 0.5-3 parts of defoamer, and 25-40 parts of water.

2. The hollow fiber membrane sealing agent according to claim 1, characterized in that, The nano-calcium carbonate has a particle size D1, which is 25 nm to 100 nm.

3. The hollow fiber membrane sealing agent according to claim 1, characterized in that, The surfactant is one or more of sodium dodecylbenzenesulfonate, hexadecyltrimethylammonium bromide, fatty alcohol polyoxyethylene ether, and Tween; and / or The wetting agent is one or two of polyether-modified siloxane and sodium dioctyl sulfosuccinate; and / or The defoamer is one of polyether defoamers or silicone defoamers; and / or The water is deionized water.

4. A method for preparing a hollow fiber membrane sealing agent, characterized in that, Includes the following steps: Pretreatment of nano-calcium carbonate; Mix metered amounts of water, surfactant, wetting agent, and defoamer and initially disperse to obtain a homogeneous mixed solution; A measured amount of pretreated nano-calcium carbonate is added to the mixed solution and dispersed at high speed for a predetermined first time. Then, a measured amount of defoamer is added and dispersed for a predetermined second time before filtration to obtain the hollow fiber membrane sealing agent as described in any one of claims 1-3.

5. The method for preparing the hollow fiber membrane sealing agent according to claim 4, characterized in that, The initial dispersion is achieved by stirring with a stirrer at a speed of 300 r / min to 500 r / min for 1 min to 15 min.

6. The method for preparing the hollow fiber membrane sealing agent according to claim 4, characterized in that, The high-speed dispersion is achieved by stirring with a stirrer at a speed of 800 r / min to 1200 r / min for 10 min to 45 min.

7. The method for preparing the hollow fiber membrane sealing agent according to claim 4, characterized in that, The redispersion is carried out by stirring with a stirrer at a speed of 300r / min to 500r / min for 5min to 10min.

8. The method for preparing the hollow fiber membrane sealing agent according to claim 4, characterized in that, The pretreatment steps for nano-calcium carbonate include: Coupling activation treatment; and Dry in a drying oven at 80℃~120℃ for 2h~4h.

9. The method for preparing the hollow fiber membrane sealing agent according to claim 4, characterized in that, After adding a measured amount of defoamer and redispersing for a predetermined second time, the mixture is filtered to obtain the hollow fiber membrane sealing agent. The hollow fiber membrane sealant is filtered through a 100-200 mesh screen and then sealed and stored in a cool, dry place at a temperature of 5℃-30℃.

10. A method for sealing a hollow fiber membrane, characterized in that, Includes the following steps: Apply the hollow fiber membrane sealing agent according to any one of claims 1-3 to the membrane fiber ends of the hollow fiber membrane bundle, or soak the hollow fiber membrane bundle. Perform drying and curing treatment; Perform potting compound filling, and then remove excess potting compound to remove the sealant.

11. The hollow fiber membrane sealing method according to claim 10, characterized in that, In the step of impregnating the hollow fiber membrane bundle with the hollow fiber membrane sealing agent, the impregnation depth is 2mm~3mm and the impregnation time is 1min~2min.

12. The hollow fiber membrane sealing method according to claim 10, characterized in that, In the drying and curing process, Place the hollow fiber membrane filament, after sealing the port, in a ventilated area; Dry at room temperature for 1 to 4 hours, or blow with hot air at 30°C to 50°C for 10 to 30 minutes.

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