A method for preparing MABR membrane based on the recycling of waste PTFE hollow fiber membrane, the regenerated MABR membrane and its applications.

Abstract

This invention belongs to the field of MABR membrane technology and relates to a method for preparing a MABR membrane based on the recycling of waste PTFE hollow fiber membrane, the regenerated MABR membrane and its application. The preparation method includes: (1) ultrasonically cleaning the waste PTFE hollow fiber membrane in a mixed cleaning solution of water and alcohol to obtain a pretreated PTFE hollow fiber membrane; (2) immersing the pretreated PTFE hollow fiber membrane in a coating solution and then curing it at 60~180℃ to obtain a non-porous dense MABR membrane; the regenerated MABR membrane has good oxygen permeability and can be effectively applied in the field of water treatment.

Description

Technical Field

[0001] This invention belongs to the field of MABR membrane technology, and relates to a method for preparing a MABR membrane based on the recycling of waste PTFE hollow fiber membranes, the regenerated MABR membrane, and its applications. Background Technology

[0002] With the development of modern technology and the improvement of living standards, wastewater treatment technologies are constantly evolving. Membrane aerated bioreactors (MABRs) have gained widespread attention and application in the water treatment field due to their advantages such as high-efficiency mass transfer and simultaneous membrane aeration and biofilm reaction. However, membrane fouling is a particularly prominent problem in MABR membrane modules during long-term operation: the membrane material is in continuous contact with wastewater and activated sludge systems, and its surface easily adsorbs microbial flocs, sludge colloids, and suspended particles, thereby clogging the membrane pores, reducing oxygen transfer efficiency, and significantly increasing the frequency of membrane cleaning and shortening the service life of the membrane module, becoming a key bottleneck restricting the stable operation of MABR technology. Currently, MABR membrane fouling control mostly relies on periodic chemical cleaning, which can restore membrane flux to a certain extent, but it is easy to cause damage to the membrane material and shorten the service life. Although some antifouling modified coatings can alleviate fouling, there is generally a contradiction between antifouling performance and membrane permeability. If the coating is too thick, it will easily clog the membrane pores and reduce mass transfer efficiency; if the coating is too thin, it is difficult to achieve long-term antifouling and cannot meet the requirements of engineering applications.

[0003] In the field of water pollution control, with the acceleration of industrialization and urbanization, nitrogen pollution in urban sewage and industrial wastewater is becoming increasingly serious. Excessive nitrogen discharge into water bodies can easily lead to eutrophication, disrupt the balance of aquatic ecosystems, and even threaten the safety of drinking water sources. Traditional biological nitrogen removal processes generally suffer from drawbacks such as large footprint, high energy consumption, and nitrogen removal efficiency being easily affected by fluctuations in influent water quality. Especially for wastewater with low C / N ratios (such as municipal sewage effluent and industrial low-concentration organic wastewater), additional carbon sources are often required to ensure denitrification, significantly increasing operating costs and treatment difficulty. MABR technology achieves bubble-free aeration through a permeable membrane, creating aerobic / anoxic / anaerobic microenvironments on the membrane surface, providing ideal conditions for simultaneous nitrification and denitrification. It has outstanding advantages such as high aeration efficiency, low energy consumption, and small footprint, and has broad application prospects in the field of wastewater nitrogen removal. However, existing commercial MABR membrane materials generally suffer from problems such as insufficient oxygen mass transfer efficiency, poor biofilm loading stability, and weak antifouling ability, making it difficult to adapt to the high-efficiency nitrogen removal requirements of wastewater with low C / N ratios, thus limiting the large-scale promotion of MABR technology in deep nitrogen removal scenarios for wastewater.

[0004] Meanwhile, the large-scale accumulation of waste polytetrafluoroethylene (PTFE) hollow fiber membranes (such as end-of-life ultrafiltration / microfiltration membrane modules) not only wastes resources due to their extremely high chemical stability, difficulty in natural degradation, and high recycling costs, but also poses potential environmental pressures. Waste PTFE hollow fiber membranes possess excellent chemical corrosion resistance, a stable pore structure, and good air permeability and hydrophobicity. If they are functionalized through reasonable recycling and targeted modification, transforming them into breathable membrane materials suitable for MABR (Maintenance, Biofilm, and Ride) processes, it can achieve solid waste resource utilization, reduce environmental burden, lower MABR membrane manufacturing costs, and potentially achieve high oxygen transfer efficiency, suitable biofilm loading, and excellent antifouling performance.

[0005] In summary, the development of a MABR membrane material based on the recycling and modification of waste PTFE hollow fiber membranes, and the construction of a matching wastewater denitrification application process and device, can simultaneously achieve solid waste resource utilization, cost reduction, and efficient deep denitrification of wastewater. This effectively addresses many shortcomings of traditional denitrification processes and existing MABR technologies, and has significant theoretical and engineering application value for promoting the green and low-carbon upgrading of wastewater treatment and improving the efficiency of water environment governance. Summary of the Invention

[0006] The purpose of this invention is to address the aforementioned problems in the existing technology by proposing a method for preparing a MABR membrane based on the recycling of waste PTFE hollow fiber membranes. Through steps such as pretreatment with a mixed cleaning solution, coating with a coating solution, and curing, a regenerated MABR membrane with a non-porous and dense structure is obtained. This regenerated MABR membrane has good oxygen permeability and can be effectively applied in the field of water treatment.

[0007] One objective of this invention is achieved through the following technical solution: A method for preparing a MABR membrane based on the recycling and regeneration of waste PTFE hollow fiber membranes includes the following steps: (1) The waste PTFE hollow fiber membrane was placed in a mixed cleaning solution of water and alcohol for ultrasonic cleaning to obtain a pretreated PTFE hollow fiber membrane. (2) The pretreated PTFE hollow fiber membrane is immersed in the coating solution and then cured at 60~180℃ to obtain a non-porous dense MABR membrane. The coating liquid comprises the following components by mass percentage: 5-30 wt% epoxy resin, 3-15 wt% curing agent, 0.5-3 wt% crosslinking agent, 0.5-4 wt% micron particles, 0.5-4 wt% nanoparticles, and the balance being solvent.

[0008] Preferably, in step (1), the alcohol in the water and alcohol mixture includes at least one of methanol, ethanol and propanol.

[0009] Preferably, in step (1), the volume percentage of alcohol in the water and alcohol mixture is 10-70 vol.

[0010] Further preferred, in step (1), the mixed cleaning solution of water and alcohol includes the following components by volume percentage: 10-40 vol% ethanol, 5-15 vol% methanol, 0.1-1 vol% propanol, and the balance being water.

[0011] Preferably, in step (1), the ultrasonic cleaning temperature is 20~80℃, the time is 10~300min, and the ultrasonic power is 50~500W.

[0012] Preferably, in step (2), the epoxy resin in the coating liquid includes at least one of bisphenol type epoxy resin, phenolic epoxy resin, and hydrogenated bisphenol type epoxy resin. The crosslinking agent includes at least one of ethylenediamine, diethylenetriamine, and m-phenylenediamine; The average particle size of the nanoparticles is 1~100 nm, including at least one of titanium dioxide nanoparticles, zinc oxide nanoparticles, graphene nanoparticles, and manganese dioxide nanoparticles. The average particle size of the micron particles is 1~100μm, including at least one of ceramic micro powder, activated carbon micron particles, silica microspheres, and calcium carbonate micron particles. The curing agent includes at least one of polydimethylsiloxane, benzaldehyde peroxide, and methyltrimethoxysilane.

[0013] Preferably, in step (2), the coating liquid includes the following components by mass percentage: 10-30 wt% epoxy resin, 5-15 wt% curing agent, 0.5-2 wt% crosslinking agent, 1-4 wt% micron particles, 1-4 wt% nanoparticles, and the balance being solvent.

[0014] Preferably, in step (2), the solid content of the coating liquid is 10-50%.

[0015] Further preferred, in step (2), the solid content of the coating liquid is 15-30%.

[0016] Preferably, in step (2), the solvent in the coating liquid includes at least one of xylene, acetone, and ethyl acetate.

[0017] Preferably, in step (2), the total mass ratio of micron-sized particles and nano-sized particles in the coating liquid is 2-6 wt%.

[0018] Preferably, in step (2), the mass ratio of micron particles to nanoparticles in the coating liquid is 1:(0.5~2).

[0019] Preferably, in step (2), the soaking time is 1 to 60 minutes.

[0020] Preferably, in step (2), the curing temperature is 70~140℃ and the time is 1~12h.

[0021] The second objective of this invention is achieved through the following technical solution: A regenerated MABR membrane is prepared by the above-described method for preparing a MABR membrane based on the recycling of waste PTFE hollow fiber membrane.

[0022] Preferably, the regenerated MABR membrane has a non-porous and dense structure.

[0023] Preferably, the initial oxygen flux of the regenerated MABR membrane is ≥9.4 L / (m²). 3 •h), tensile strength at break ≥450N.

[0024] Further preferably, the initial oxygen flux of the regenerated MABR membrane is ≥10 L / (m²). 3 •h), tensile strength at break ≥480N.

[0025] The third objective of this invention is achieved through the following technical solution: An application of the above-described regenerated MABR membrane in water treatment.

[0026] Preferably, the application includes: immersing the regenerated MABR membrane in the wastewater to be treated, supplying air by a blower, and allowing oxygen to diffuse through the membrane wall of the regenerated MABR membrane in a molecular state under bubble-free conditions, thereby establishing a dissolved oxygen gradient on its surface and driving the mass transfer of pollutants, including COD and ammonia nitrogen, in the wastewater to the membrane surface.

[0027] The fourth objective of this invention is achieved through the following technical solution: An integrated modular reactor for water treatment includes the aforementioned regenerated MABR membrane.

[0028] Preferably, the integrated modular reactor for water treatment includes an oxygen-permeable membrane and a biofilm, wherein the oxygen-permeable membrane is a regenerated MABR membrane; In the integrated modular reactor for water treatment, the oxygen-permeable membrane is immersed in the wastewater to be treated. A blower supplies air to the membrane cavity, allowing oxygen to diffuse through the membrane wall to the biofilm layer in a bubble-free environment. This creates a dissolved oxygen gradient along the thickness of the biofilm, with higher dissolved oxygen levels near the membrane and lower levels further away. This gradient drives COD and ammonia nitrogen pollutants in the wastewater to transfer mass to the membrane surface and enter the biofilm. This results in a reverse diffusion mass transfer process between oxygen and substrate within the biofilm. In the aerobic zone of the inner biofilm layer near the oxygen-permeable membrane, nitrifying bacteria convert ammonia nitrogen into nitrate nitrogen. In the anoxic zone of the outer biofilm layer, denitrifying bacteria use a carbon source to reduce nitrate nitrogen back to nitrogen gas, achieving simultaneous decarbonization and denitrification.

[0029] More preferably, the ammonia nitrogen concentration of the wastewater to be treated is 30~300 mg / L, including at least one of municipal sewage, industrial wastewater or aquaculture wastewater.

[0030] Further preferred, when the ammonia nitrogen concentration of the wastewater to be treated is 30~50 mg / L, the ammonia nitrogen removal rate is ≥95%; when the ammonia nitrogen concentration of the wastewater to be treated is 50~300 mg / L, the ammonia nitrogen removal rate is ≥90%.

[0031] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention proposes for the first time a method for preparing MABR membranes based on the recycling of waste polytetrafluoroethylene hollow fiber membranes. Through steps such as pretreatment with a mixed cleaning solution, coating with a coating solution, and curing, the high-value recycling of waste membrane materials is achieved, breaking through the technical barrier of traditional MABR membranes relying on new polymer materials, and providing a new path for the green preparation and recycling of membrane materials.

[0032] 2. This invention forms a uniform and structurally controllable oxygen-permeable layer on the surface of a PTFE hollow fiber membrane. The resulting regenerated MABR membrane exhibits a non-porous and dense structure, allowing oxygen to permeate through the membrane wall in the form of molecular diffusion, achieving bubble-free aeration. The oxygen utilization rate is significantly higher than that of traditional microporous membranes. At the same time, the presence of the dense layer effectively prevents wastewater from directly penetrating, ensuring the long-term stability of the membrane module.

[0033] 3. This invention enhances the surface roughness of the membrane by introducing micron-sized particles into the coating solution, providing more microbial attachment sites; nanoparticles regulate the hydrophobic properties of the membrane surface and optimize oxygen mass transfer efficiency; and epoxy resin as the matrix endows the regenerated membrane with excellent mechanical strength and chemical corrosion resistance, so that the membrane material has both excellent mechanical properties and biocompatibility.

[0034] 4. This invention can flexibly control the film thickness, density and surface characteristics by adjusting the composition ratio of the coating liquid and the curing temperature, so as to meet the different requirements of oxygen permeable membrane performance in different water treatment scenarios and has good designability and adaptability.

[0035] 5. The regenerated MABR membrane prepared by this invention can be integrated with modular reactors and flexibly combined and deployed according to actual conditions such as river width and water volume to meet the treatment needs of water bodies of different sizes. By dynamically adjusting the aeration intensity, it can achieve precise control of the dissolved oxygen gradient on the membrane surface, avoiding the problems of sediment disturbance and secondary pollution caused by traditional aeration methods. It is especially suitable for decentralized sewage treatment and upgrading of existing sewage treatment plants. Detailed Implementation

[0036] The technical solution of the present invention will be further described and illustrated below through specific embodiments. It should be understood that the specific embodiments described herein are only for the purpose of helping to understand the present invention and are not intended to limit the present invention.

[0037] Unless otherwise specified, the raw materials used in the embodiments of the present invention are all commonly used in the art, and the methods used in the embodiments are all conventional methods in the art.

[0038] In this article, the raw materials include: Titanium dioxide nanoparticles with an average particle size of 5~80 nm; Ceramic micro powder, with an average particle size of 5~50μm; Activated carbon micron-sized particles, with an average particle size of 5~50μm; Zinc oxide nanoparticles with an average particle size of 5-80 nm; In this paper, the testing process includes: the initial oxygen flux is tested according to GB / T 42281-2022, and the tensile strength at break is tested according to GB / T 1040.1-2025.

[0039] Example 1

[0040] The method for preparing MABR membrane based on the recycling of waste PTFE hollow fiber membrane in this embodiment includes the following steps: By volume percentage, 30 vol% ethanol, 15 vol% methanol, 0.1 vol% propanol, and the remainder deionized water were mixed to obtain a mixed cleaning solution. Waste PTFE hollow fiber membranes were immersed in the mixed cleaning solution, and ultrasonic cleaning was performed at 25°C for 60 minutes with an ultrasonic power of 100W to obtain a pretreated PTFE hollow fiber membrane. 10 parts phenolic epoxy resin, 6 parts benzaldehyde peroxide, 2 parts diethylenetriamine, 1 part titanium dioxide nanoparticles, and 2 parts ceramic powder were added to 79 parts xylene and mixed thoroughly to prepare a coating solution. The pretreated PTFE hollow fiber membrane was immersed in the coating solution for 20 minutes, then removed and cured at 70°C for 3 hours to obtain a non-porous and dense regenerated MABR membrane.

[0041] Performance testing was conducted, and in this embodiment, the initial oxygen flux of the regenerated MABR membrane was 12.6 L / (m²). 3 The tensile strength at break is 489 N.

[0042] Example 2

[0043] The method for preparing MABR membrane based on the recycling of waste PTFE hollow fiber membrane in this embodiment includes the following steps: By volume percentage, 40 vol% ethanol, 15 vol% methanol, 1 vol% propanol, and the remainder deionized water were mixed to obtain a mixed cleaning solution. Waste PTFE hollow fiber membranes were immersed in the mixed cleaning solution, and ultrasonic cleaning was performed at 30°C for 60 minutes with an ultrasonic power of 100W to obtain a pretreated PTFE hollow fiber membrane. 20 parts hydrogenated bisphenol epoxy resin, 5 parts polydimethylsiloxane, 1 part ethylenediamine, 2 parts activated carbon micron particles, and 1 part zinc oxide nanoparticles were added to 71 parts ethyl acetate and mixed thoroughly to prepare a coating solution. The pretreated PTFE hollow fiber membrane was immersed in the coating solution for 15 minutes, then removed and cured at 120°C for 2 hours to obtain a non-porous and dense regenerated MABR membrane.

[0044] Performance testing was conducted, and in this embodiment, the initial oxygen flux of the regenerated MABR membrane was 11.8 L / (m²). 3 The tensile strength at break is 502 N.

[0045] Example 3

[0046] The method for preparing MABR membrane based on the recycling of waste PTFE hollow fiber membrane in this embodiment differs from that in Example 1 in that, by volume percentage, 30 vol% ethanol, 10 vol% methanol, 0.5 vol% propanol and the remainder deionized water are mixed to obtain a mixed cleaning solution.

[0047] Performance testing was conducted, and in this embodiment, the initial oxygen flux of the regenerated MABR membrane was 11.2 L / (m²). 3 The tensile strength at break is 506 N.

[0048] Example 4

[0049] The method for preparing MABR membrane based on the recycling of waste PTFE hollow fiber membrane in this embodiment differs from that in Example 1 in that, by volume percentage, 30 vol% ethanol, 10 vol% methanol and the remainder deionized water are mixed to obtain a mixed cleaning solution.

[0050] Performance testing was conducted, and in this embodiment, the initial oxygen flux of the regenerated MABR membrane was 9.4 L / (m²). 3 ·h), the tensile strength at break is 505N.

[0051] Example 5

[0052] The method for preparing MABR membrane based on the recycling of waste PTFE hollow fiber membrane in this embodiment differs from that in Example 1 in that 10 parts of phenolic epoxy resin, 6 parts of benzaldehyde peroxide, 2 parts of diethylenetriamine, 1 part of titanium dioxide nanoparticles, and 2 parts of ceramic powder are added to 98 parts of xylene and mixed evenly to obtain a coating solution.

[0053] Performance testing was conducted, and in this embodiment, the initial oxygen flux of the regenerated MABR membrane was 9.2 L / (m²). 3 The tensile strength at break is 512 N.

[0054] Example 6

[0055] The method for preparing MABR membrane based on the recycling of waste PTFE hollow fiber membrane in this embodiment differs from that in Example 1 in that 10 parts of phenolic epoxy resin, 6 parts of benzaldehyde peroxide, 2 parts of diethylenetriamine, 1 part of titanium dioxide nanoparticles, and 2 parts of ceramic micro powder are added to 60 parts of xylene and mixed evenly to obtain a coating solution.

[0056] Performance testing was conducted, and in this embodiment, the initial oxygen flux of the regenerated MABR membrane was 8.2 L / m³. 3 •h, the tensile strength at break is 500N.

[0057] Comparative Example 1 The method for preparing the MABR membrane based on the recycling of waste PTFE hollow fiber membrane in this comparative example includes the following steps: Waste PTFE hollow fiber membranes were immersed in deionized water, and ultrasonic cleaning was performed at 25°C for 60 minutes with an ultrasonic power of 100W to obtain pretreated PTFE hollow fiber membranes. The pretreated PTFE hollow fiber membranes were then immersed in the coating solution from Example 1 for 20 minutes, removed, and cured at 70°C for 3 hours to obtain regenerated MABR membranes.

[0058] Performance testing was conducted, and the initial oxygen flux of the regenerated MABR membrane in this comparative example was 6.0 L / (m²). 3 The tensile strength at break is 502 N.

[0059] Comparative Example 2 The method for preparing the MABR membrane based on the recycling of waste PTFE hollow fiber membrane in this comparative example includes the following steps: By volume percentage, 30 vol% ethanol, 15 vol% methanol, 0.1 vol% propanol, and the remainder deionized water were mixed to obtain a mixed cleaning solution. Waste PTFE hollow fiber membranes were immersed in the mixed cleaning solution, and ultrasonic cleaning was performed at 25°C for 60 minutes with an ultrasonic power of 100W to obtain a pretreated PTFE hollow fiber membrane. 10 parts phenolic epoxy resin, 6 parts benzaldehyde peroxide, 2 parts diethylenetriamine, and 3 parts titanium dioxide nanoparticles were added to 79 parts xylene and mixed thoroughly to prepare a coating solution. The pretreated PTFE hollow fiber membrane was immersed in the coating solution for 20 minutes, then removed and cured at 70°C for 3 hours to obtain a regenerated MABR membrane.

[0060] In performance testing, the regenerated MABR membrane in this comparative example was unable to allow oxygen to permeate via molecular diffusion, resulting in the generation of larger bubbles.

[0061] Comparative Example 3 The method for preparing the MABR membrane based on the recycling of waste PTFE hollow fiber membrane in this comparative example includes the following steps: By volume percentage, 30 vol% ethanol, 15 vol% methanol, 0.1 vol% propanol, and the balance deionized water were mixed to obtain a mixed cleaning solution. Waste PTFE hollow fiber membranes were immersed in the mixed cleaning solution, and ultrasonic cleaning was performed at 25°C for 60 minutes with an ultrasonic power of 100W to obtain pretreated PTFE hollow fiber membranes. 10 parts phenolic epoxy resin, 6 parts benzaldehyde peroxide, 2 parts diethylenetriamine, and 3 parts ceramic micropowder were added to 79 parts xylene and mixed thoroughly to prepare a coating solution. The pretreated PTFE hollow fiber membranes were immersed in the coating solution for 20 minutes, then removed and cured at 70°C for 3 hours to obtain a regenerated MABR membrane.

[0062] In performance testing, the regenerated MABR membrane in this comparative example was unable to allow oxygen to permeate via molecular diffusion, resulting in the generation of larger bubbles.

[0063] Comparative Example 4 The method for preparing the MABR membrane based on the recycling of waste PTFE hollow fiber membrane in this comparative example includes the following steps: By volume percentage, 30 vol% ethanol, 15 vol% methanol, 0.1 vol% propanol, and the remainder deionized water were mixed to obtain a mixed cleaning solution. Waste PTFE hollow fiber membranes were immersed in the mixed cleaning solution, and ultrasonic cleaning was performed at 25°C for 60 minutes with an ultrasonic power of 100W to obtain pretreated PTFE hollow fiber membranes. 10 parts phenolic epoxy resin, 6 parts benzaldehyde peroxide, 2 parts diethylenetriamine, 5 parts titanium dioxide nanoparticles, and 5 parts ceramic powder were added to 72 parts xylene and mixed thoroughly to prepare a coating solution. The pretreated PTFE hollow fiber membranes were immersed in the coating solution for 20 minutes, then removed and cured at 70°C for 3 hours to obtain a regenerated MABR membrane.

[0064] Performance testing was conducted, and the initial oxygen flux of the regenerated MABR membrane in this comparative example was 8.1 L / (m²). 3 The tensile strength at break is 496 N.

[0065] As described above, within a certain range, as the solid loading in the coating solution on the pretreated PTFE hollow fiber membrane increases (changing the solid content), the initial oxygen flux of the regenerated MABR membrane gradually decreases, while the tensile strength at break remains essentially unchanged. Furthermore, the addition of micron / nano particles to the coating solution has a crucial impact on membrane performance: if no micron and / or nano particles are added to the coating solution, the regenerated MABR membrane cannot achieve effective oxygen permeation, only generating large bubbles; if too many particles are added, the initial oxygen flux of the regenerated MABR membrane will decrease. In addition, an alcohol solvent must be added to the cleaning solution used in the pretreatment process; otherwise, the oxygen permeation efficiency will be affected.

[0066] In summary, the regenerated MABR membrane prepared by this invention has excellent initial oxygen flux and tensile strength at break. Its non-porous and dense structure allows oxygen to permeate through the membrane wall in the form of molecular diffusion, achieving bubble-free aeration, and can be widely used in the field of water treatment.

[0067] All aspects, embodiments, and features of this invention should be considered illustrative in all respects and not limiting of the invention; the scope of the invention is defined only by the claims. Other embodiments, modifications, and uses will become apparent to those skilled in the art without departing from the spirit and scope of the invention as claimed.

[0068] In the preparation method of this invention, the order of the steps is not limited to the listed order. For those skilled in the art, variations in the order of the steps without creative effort are also within the scope of protection of this invention. Furthermore, two or more steps or actions can be performed simultaneously.

[0069] Finally, it should be noted that the specific embodiments described herein are merely illustrative examples of the invention and are not intended to limit the implementation of the invention. Those skilled in the art can make various modifications or additions to the described specific embodiments or use similar methods to replace them; it is neither necessary nor possible to exemplify all embodiments here. However, these obvious variations or modifications derived from the essential spirit of the invention still fall within the scope of protection of the invention, and interpreting them as any additional limitation would contradict the spirit of the invention.

Claims

1. A method for preparing a MABR membrane based on the recycling and regeneration of waste PTFE hollow fiber membranes, characterized in that, The preparation method includes the following steps: (1) The waste PTFE hollow fiber membrane was placed in a mixed cleaning solution of water and alcohol for ultrasonic cleaning to obtain a pretreated PTFE hollow fiber membrane. (2) The pretreated PTFE hollow fiber membrane is immersed in the coating solution and then cured at 60~180℃ to obtain a non-porous dense MABR membrane. The coating liquid comprises the following components by mass percentage: 5-30 wt% epoxy resin, 3-15 wt% curing agent, 0.5-3 wt% crosslinking agent, 0.5-4 wt% micron particles, 0.5-4 wt% nanoparticles, and the balance being solvent.

2. The method for preparing MABR membrane based on the recycling and regeneration of waste PTFE hollow fiber membrane according to claim 1, characterized in that, In step (1), the volume percentage of alcohol in the water and alcohol mixture is 10-70 vol%. The alcohols include at least one of methanol, ethanol, and propanol.

3. The method for preparing MABR membrane based on the recycling and regeneration of waste PTFE hollow fiber membrane according to claim 1, characterized in that, In step (1), the ultrasonic cleaning temperature is 20~80℃, the time is 10~300min, and the ultrasonic power is 50~500W.

4. The method for preparing MABR membrane based on the recycling and regeneration of waste PTFE hollow fiber membrane according to claim 1, characterized in that, In step (2), the epoxy resin in the coating liquid includes at least one of bisphenol type epoxy resin, phenolic epoxy resin, and hydrogenated bisphenol type epoxy resin; The crosslinking agent includes at least one of ethylenediamine, diethylenetriamine, and m-phenylenediamine; The average particle size of the nanoparticles is 1~100 nm, including at least one of titanium dioxide nanoparticles, zinc oxide nanoparticles, graphene nanoparticles, and manganese dioxide nanoparticles. The average particle size of the micron particles is 1~100μm, including at least one of ceramic micro powder, activated carbon micron particles, silica microspheres, and calcium carbonate micron particles. The curing agent includes at least one of polydimethylsiloxane, benzaldehyde peroxide, and methyltrimethoxysilane.

5. The method for preparing a MABR membrane based on the recycling and regeneration of waste PTFE hollow fiber membrane according to claim 1, characterized in that, In step (2), the solvent in the coating liquid includes at least one of xylene, acetone, and ethyl acetate.

6. The method for preparing a MABR membrane based on the recycling and regeneration of waste PTFE hollow fiber membrane according to claim 1, characterized in that, In step (2), the soaking time is 1 to 60 minutes.

7. The method for preparing a MABR membrane based on the recycling and regeneration of waste PTFE hollow fiber membrane according to claim 1, characterized in that, In step (2), the curing temperature is 70~140℃ and the time is 1~12h.

8. A regenerated MABR membrane, characterized in that, It is prepared by the method for preparing MABR membrane based on the recycling of waste PTFE hollow fiber membrane as described in any one of claims 1 to 7.

9. The regenerated MABR membrane according to claim 8, characterized in that, The regenerated MABR membrane has a non-porous and dense structure; The initial oxygen flux of the regenerated MABR membrane is ≥9.4 L / m. 3 •h, tensile strength at break ≥450 N.

10. The application of a regenerated MABR membrane as described in claim 8 in water treatment.