Lining water treatment membrane with self-repairing function as well as preparation method and application of lining water treatment membrane

Abstract

The invention discloses a lining water treatment membrane with a self-repairing effect and application thereof. The lining water treatment membrane comprises a lining substrate with a porous structure and a water treatment separation membrane layer arranged on the lining substrate, the lining substrate comprises a supporting layer and a combining layer, the supporting layer comprises a lining structure composed of first fiber filaments, and the combining layer comprises a blocking area formed by the first fiber filaments and second fiber filaments which are arranged in a staggered mode; the diameter of the first fiber yarn is larger than that of the second fiber yarn, and a plurality of pits are formed in the second fiber yarn; a part of area of the water treatment separation membrane layer is positioned in the blocking area and is in contact with the first fiber yarns and the second fiber yarns in the blocking area respectively; the preparation method comprises the following steps: applying a membrane casting solution of the water treatment separation membrane to the lining substrate, and carrying out coagulating bath exchange phase separation, the lining water treatment film can be self-repaired after the surface of the film is damaged, a chemical improver does not need to be additionally added to modify a film layer on the surface, and the lining water treatment film is simple and easy to operate and high in economical efficiency.

Description

Technical Field

[0001] The invention relates to the field of water treatment, and in particular to a liner water treatment membrane with self-repairing function, a preparation method and application thereof. Background Art

[0002] Membrane preparation and separation technology are relatively mature, and are currently widely used in water treatment in various industries, including municipal administration, printing and dyeing, chemical industry, electronics, petrochemical industry, medicine, new energy, river management, etc. In actual application, membrane products will suffer from pollution loss, which will affect the water quality and service life of the produced water and increase the cost of water treatment. At present, research is being conducted to prepare polymer separation membrane materials with self-repairing function to achieve the durable service life of water treatment membranes. In actual use, when the water treatment membrane is damaged, the materials that are repaired autonomously are used to achieve the overall performance of the water treatment membrane without affecting it. For example, Chinese patent CN104174297A dissolves one or more block copolymers into the casting liquid to form a self-repairing surface with a spherical or rod-shaped micelle structure; another example is Chinese patent CN106943892A. An isocyanate-terminated repair agent is added to the casting liquid to cause it to cross-link when it encounters water, and the repair material is quickly combined with the membrane material. However, these repair methods all require the addition of polymers in the preparation of the casting liquid, which has relatively high requirements for membrane preparation and production, and the cost will also be high.

[0003] It should be noted that the information disclosed in the above background technology section is only used to understand the background of the present application, so the background technology section of the present invention may contain background information about the problem or environment of the present invention, but not necessarily describe the prior art. Therefore, the content contained in the background technology section is not an admission of the applicant to the prior art. Summary of the invention

[0004] The purpose of the present invention is to overcome one or more deficiencies in the prior art and to provide an improved lined water treatment membrane that can self-repair after the membrane surface is damaged. It does not require the addition of additional chemical modifiers to modify the surface membrane layer, is simple and easy to operate, and is highly economical.

[0005] The present invention also provides a method for preparing the above-mentioned inner-lined water treatment membrane and its application in water treatment.

[0006] Generally, in the field of water treatment, it is generally recognized that the membrane layer on the surface of the separation membrane needs to be smooth to form a relatively flat plane structure, thereby avoiding the problem of clogging the holes of the separation membrane by other substances such as sludge or bacterial colonies adhering to and accumulating on it during the water treatment process;

[0007] Based on the defects of existing water treatment membranes that cannot self-repair when damaged or that it is difficult to prepare water treatment membranes with self-repairing properties, the inventors of the present invention have innovatively used the bacteria and sludge existing in the water body to achieve self-repair of the water treatment membrane after a large number of experimental studies. Specifically, the present invention increases the specific surface area of ​​the lining substrate by providing a pit structure on the lining substrate, thereby achieving that when the surface water treatment separation membrane layer is damaged, the presence of the pit structure greatly increases the possibility of sludge and bacteria adhesion. Due to the presence of this rough structure, when the sludge and bacteria move to that place in the water body, they will inevitably be adsorbed or accumulated there, thereby based on the bacteria. The colony can grow by itself, and a large number of colony aggregates can be formed at the damaged parts of the membrane in a relatively short period of time. When these colony aggregates are mixed with sludge and piled up, a barrier is formed, which can prevent the water to be treated from directly discharging through the damaged gaps. It is equivalent to putting a "patch" on the damaged parts of the membrane, thereby realizing the self-repair of the membrane. Moreover, the repair process does not require the addition of special substances to the membrane layer, and can only rely on the characteristics of the water body itself to achieve self-repair. In addition, the damaged parts themselves are very few and tiny. This repair method basically does not cause a decrease in the separation efficiency of the water treatment membrane, increases the service life of the water treatment membrane, and has better economic effects.

[0008] In order to achieve the above object, a technical solution adopted by the present invention is:

[0009] A lined water treatment membrane, comprising an inner lining substrate having a porous structure and a water treatment separation membrane layer arranged on the inner lining substrate;

[0010] The lining substrate comprises a supporting layer and a bonding layer, wherein the supporting layer comprises a lining structure composed of first fiber filaments, and the bonding layer comprises a barrier region formed by mutually staggered arrangement of first fiber filaments and second fiber filaments, wherein at least part of the first fiber filaments in the barrier region are the first fiber filaments in the lining structure;

[0011] The diameter of the first fiber filament is greater than the diameter of the second fiber filament, and a plurality of pits are formed on the second fiber filament;

[0012] The water treatment separation membrane layer has a partial area located in the barrier area, and the partial area is in contact with the first fiber filaments and the second fiber filaments in the barrier area respectively.

[0013] In some embodiments of the present invention, the diameter of the first fiber filament is 0.5-4 mm.

[0014] In some embodiments of the present invention, the fineness of the second fiber filament is 300D-1200D.

[0015] In some embodiments of the present invention, the specific surface area of ​​the second fiber filaments is 2000-5000 square meters per cubic meter.

[0016] In some embodiments of the present invention, the material of the first fiber filament includes one or more selected from the group consisting of polyamide, polypropylene, polycarbonate, and polybutylene succinate.

[0017] In some embodiments of the present invention, the material of the second fiber filament includes one or more selected from the group consisting of polyester, polyvinyl alcohol, and polyacrylonitrile.

[0018] In some embodiments of the present invention, the lining base is a base structure having a supporting function, such as a knitted tube or a woven cloth.

[0019] In some embodiments of the present invention, the lining substrate is formed by weaving the first fiber filaments and the second fiber filaments.

[0020] In some embodiments of the present invention, there are two bonding layers respectively located on the upper and lower surfaces of the support layer, and there are two water treatment separation membrane layers corresponding to the bonding layers one by one.

[0021] In some embodiments of the present invention, the thickness of the lining substrate is 0.5-2 mm. When corresponding to a tubular shape, the diameter may be 0.5-2 mm.

[0022] In some embodiments of the present invention, the thickness of the water treatment separation membrane layer is 0.06-0.15 mm.

[0023] In some embodiments of the present invention, in the lining substrate, the ratio of the number of the first fiber filaments to the number of the second fiber filaments is 1:2-3.

[0024] In some embodiments of the present invention, the lining structure is not in contact with the water treatment separation membrane layer.

[0025] Another technical solution provided by the present invention is: a lined water treatment membrane, the lined water treatment membrane comprising a lining substrate having a porous structure and a plurality of pit structures and a water treatment separation membrane layer arranged on the lining substrate;

[0026] At least part of the plurality of pit structures faces the water treatment separation membrane layer.

[0027] In some embodiments of the present invention, the water treatment separation membrane layer has a partial area located in any one of the pit structures.

[0028] In some embodiments of the present invention, the lining substrate includes a first fiber filament and a second fiber filament having the pit structure, wherein a portion of the first fiber filament is staggered with the second fiber filament to form a barrier zone, and the remaining first fiber filaments form a lining structure; wherein the water treatment separation membrane layer has a partial area located in the barrier zone, and the partial area is in contact with the first fiber filament and the second fiber filament, respectively.

[0029] Another technical solution provided by the present invention is a method for preparing the above-mentioned lining water treatment membrane, the preparation method comprising:

[0030] (1) Spinning a first fiber filament and a second fiber filament into a lining substrate having a porous structure by a textile process; wherein the second fiber filament is a fiber filament having a plurality of pits formed by one or more physical and / or chemical treatments;

[0031] (2) applying a water treatment separation membrane casting solution onto the inner lining substrate and allowing it to remain in the air to form an intermediate;

[0032] (3) Placing the intermediate in a coagulation bath to form a lining water treatment membrane.

[0033] Another technical solution provided by the present invention is an application of the lined water treatment membrane in water treatment.

[0034] In some embodiments of the present invention, during the water treatment process, the lining water treatment membrane is placed in a water body to be treated that contains aerobic bacteria or anaerobic bacteria, and optionally sludge.

[0035] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0036] 1. The lining water treatment membrane of the present invention has a self-repairing effect. After the membrane material is damaged or ruptured during use, a colony barrier zone can be quickly formed on the second middle fiber to achieve a repairing effect.

[0037] 2. The water treatment membrane of the present invention can be made into hollow fiber membrane, flat membrane, roll membrane, etc. by adding lining fiber to the conventional membrane liquid formula. At the same time, it can enhance the bonding strength and pressure bearing strength of the membrane material, and at the same time, it is simple in production cost and has significant economic benefits, and can effectively increase the service life of the water treatment membrane; in particular, the high-strength lining substrate is conducive to the stable attachment of the colony and the formation of a stable barrier zone. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0039] Figure 1 This is a schematic structural diagram of the lined water treatment membrane of Example 1 of the present invention;

[0040] Figure 2 is a schematic diagram of the structure of the second fiber filament in an embodiment of the present invention;

[0041] Figure 3 This is a cross-sectional electron microscope image of the lined water treatment membrane of Example 1 of the present invention;

[0042] Figure 4 This is a schematic structural diagram of the lined water treatment membrane of Example 2 of the present invention;

[0043] Figure 5 This is a cross-sectional electron microscope image of the lined water treatment membrane of Example 2 of the present invention;

[0044] Figure 6 Schematic diagram of an experimental device for testing water quality during water treatment in an embodiment of the present invention;

[0045] Figure 7 This is the water quality test flow curve diagram of Comparative Example 1;

[0046] Figure 8 This is the turbidity curve of the water quality test of Comparative Example 1;

[0047] Fig. 9 The water quality test flow curve diagram of Example 2;

[0048] Fig.10 The turbidity curve of the water quality test in Example 2;

[0049] In the accompanying drawings: 100, lining water treatment membrane; 111, first fiber filament; 112, lining structure; 113, second fiber filament; 1131, pit; 114, barrier area; 115, hollow structure; 120, water treatment separation membrane layer; 200, water inlet tank; 300, water inlet pump; 400, water inlet valve; 500, reflux pipe; 600, treatment chamber. DETAILED DESCRIPTION

[0050] The present invention provides a new type of lining water treatment membrane that relies on the colonies and sludge existing in the water body to be treated to repair damaged water treatment membranes. Usually, in the field of water treatment, it is generally recognized that the membrane layer on the surface of the separation membrane needs to be smooth to form a relatively flat plane structure, thereby avoiding the problem of other substances such as sludge or colonies adhering and accumulating on it during the water treatment process and causing blockage of the separation membrane holes; based on a large number of experimental studies, the inventors of the present invention set a pit structure on the lining substrate to increase the specific surface area of ​​the lining substrate, thereby achieving that when the surface water treatment separation membrane layer is damaged, the presence of the pit structure greatly increases the possibility of sludge and colonies adhering. Due to the presence of this rough structure, when the sludge and colonies move to that place in the water body, they will inevitably be adsorbed or accumulated there. , and based on the characteristic that the colonies can grow by themselves, a large number of colony aggregates can be formed at the damaged parts of the membrane layer in a relatively short period of time. When these colony aggregates are mixed with sludge and accumulated, a barrier is formed, which can prevent the water to be treated from directly discharging through the damaged gaps. This is equivalent to putting a "patch" on the damaged parts of the membrane layer, thereby realizing the self-repair of the membrane layer. Moreover, the repair process does not require the addition of special substances to the membrane layer, and can only rely on the characteristics of the water body itself to achieve self-repair. In addition, the damaged parts themselves are very few and tiny. This repair method basically does not cause a decrease in the separation efficiency of the water treatment membrane, greatly increasing the service life of the water treatment membrane and having better economic effects.

[0051] Furthermore, the lining water treatment membrane of the present invention comprises a lining substrate having a porous structure and a plurality of pit structures and a water treatment separation membrane layer arranged on the lining substrate; at least part of the plurality of pit structures is oriented toward the water treatment separation membrane layer;

[0052] Alternatively, the lined water treatment membrane of the present invention comprises a lining substrate having a porous structure and a water treatment separation membrane layer arranged on the lining substrate; the lining substrate comprises a supporting layer and a bonding layer, the supporting layer comprises a lining structure composed of first fiber filaments, the bonding layer comprises a barrier region formed by the first fiber filaments and the second fiber filaments being arranged alternately with each other, and the first fiber filaments in the barrier region are at least partially the first fiber filaments in the lining structure;

[0053] The diameter of the first fiber filament is greater than that of the second fiber filament, and a plurality of pits are formed on the second fiber filament; the water treatment separation membrane layer has a partial area located in the barrier zone, and the partial area is in contact with the first fiber filament and the second fiber filament in the barrier zone respectively.

[0054] In some embodiments, the bonding layers have two layers and are respectively located on the upper and lower surfaces of the support layer, the water treatment separation membrane layers have two layers and correspond one to one with the bonding layers; the lining structure does not contact the water treatment separation membrane layers.

[0055] Furthermore, the present invention also provides a method for preparing a lined water treatment membrane, the preparation method comprising:

[0056] (1) Spinning a first fiber filament and a second fiber filament into a lining substrate having a porous structure by a textile process; wherein the second fiber filament is a fiber filament having a plurality of pits formed by one or more physical and / or chemical treatments;

[0057] (2) applying a water treatment separation membrane casting solution onto the inner lining substrate and allowing it to remain in the air to form an intermediate;

[0058] (3) Placing the intermediate in a coagulation bath to form a lining water treatment membrane.

[0059] In some embodiments, the material of the first fiber filament may include one or more components selected from PA polyamide, PP polypropylene, PC polycarbonate, PBS polybutylene succinate and the like, and the diameter of the first fiber filament is 0.5-4 mm; the material of the second fiber filament may include one or more components selected from PET polyester, PVA polyvinyl alcohol, PAN polyacrylonitrile and the like, and the fineness of the second fiber filament is 300D-1200D; the first fiber filament is thicker than the second fiber filament, which can effectively support the internal and external pressures, achieve the pressure-bearing and shape-keeping effect, and is conducive to forming a network structure with larger gaps, which is conducive to water treatment and separation;

[0060] The textile process can be conventional textile means such as knitting process or weaving process, which will not be described in detail here; for example, the first fiber filament and the second fiber filament can be knitted into a hollow fiber filament tube, i.e., a knitted tube, by mechanical equipment; or woven into a woven cloth by a weaving process. When used as an inner lining base, a single knitted tube or multiple knitted tubes can be used as the inner lining base, or a single woven cloth or multiple woven cloths can be used as the inner lining base; further, generally, in the inner lining base, the ratio of the number of the first fiber filament to the second fiber filament is 1:2-3.

[0061] In some embodiments, the one or more physical and / or chemical methods include acid etching and alkaline etching. The acid etching can be performed by immersion etching with hydrochloric acid, the mass concentration of which can be 5%-10%, and the immersion time can be 30 min-3 h; the alkaline etching can be performed by immersion etching with sodium hydroxide aqueous solution and / or potassium hydroxide aqueous solution, the mass concentration of which can be 5%-10%, and the immersion time can be 30 min-3 h; further, the acid etching and the alkaline etching can be controlled to be performed at 70-80°C, respectively. After the etching is completed, the fiber can be rinsed with clean water and dried for use. After the treatment is completed, the specific surface area of ​​the second fiber filament can reach 2000-5000 square meters per cubic meter.

[0062] In some embodiments, the water treatment separation membrane casting liquid adopts the existing conventional casting liquid. For example, the casting liquid contains, by mass percentage: 10-20% polymer, 50-70% organic solvent, and 20-30% additives; the polymer can be selected from PVDF polyvinylidene fluoride, PES polyether sulfone, PS polysulfone, PP polypropylene, PVC polyvinyl chloride, PTFE polytetrafluoroethylene, etc., the organic solvent can be selected from DMAC dimethylacetamide, DMSO dimethylformamide, DMF dimethylformamide, acetone, etc., and the additive can be selected from PEG polyethylene glycol, glycerol propylene glycol, pyrrolidone, pyridine, etc. The casting liquid is applied to the lining substrate in the following ways: spraying, scraping, casting, spinneret spinning, etc. The casting liquid will not only form a film layer on the surface of the lining substrate, but also penetrate into the lining substrate, that is, enter the barrier area, and form a bonding area where the film layer and the lining substrate are combined with each other, that is, the casting liquid penetrates into the gaps between the fiber filaments and other areas, and firmly combines with the fiber filaments, which greatly improves the stability of the film layer on the lining substrate and is not easy to fall off; then it stays in the air for a period of time, for example, 0.1-10 minutes, the organic solvent will evaporate, and a primary intermediate will be formed.

[0063] In some embodiments, the coagulation bath is in the form of an existing conventional coagulation bath, for example, the coagulation bath can be composed of a mixture of one or more of water, N-methylpyrrolidone, methanol, ethanol, dimethylformamide, and dimethylacetamide; the immersion time in the coagulation bath can be 2-1000s, and phase separation is achieved during the immersion process to generate fine membrane pores, thereby forming a porous water treatment membrane with an interception effect, which can effectively filter sewage, that is, it is made into a lining water treatment membrane; generally, the thickness of the lining substrate is 0.5-2mm, and the thickness of the water treatment separation membrane layer is 0.06-0.15mm.

[0064] In the present invention, the presence of the lining substrate can not only improve the setting stability of the water treatment separation membrane layer, but also play a good supporting role, which can effectively ensure that the entire lining water treatment membrane has a certain supporting effect and deformation ability under the action of external force, which is conducive to long-term and stable use.

[0065] In the actual preparation process, at least three forms of lined water treatment membranes can be made:

[0066] Form 1: Use a spinneret to extrude the casting liquid, and an inner lining substrate such as a knitted tube passes through the middle of the spinneret, wherein the knitted tube is a hollow fiber tube. The casting liquid extruded from the four sides of the knitted tube penetrates into the knitted tube, stays in the air for a period of time, and then enters the coagulation bath for phase separation, forming a hollow fiber membrane with a cylindrical surface porous membrane layer (water treatment separation membrane layer), an intermediate bonding layer, and an internal support layer, i.e., an inner lining water treatment membrane.

[0067] Form 2: Use the casting liquid to cast on both sides of the woven cloth, use a scraper to scrape it to a uniform thickness, and the casting liquid penetrates into the woven cloth, and then enters the coagulation bath for phase separation to form a flat membrane with two porous membrane layers (water treatment separation membrane layers), an intermediate bonding layer, and an internal support layer, that is, a lined water treatment membrane.

[0068] Form three: Use the casting liquid to cast on one side of the woven cloth, use a scraper to scrape it to a uniform thickness, and let the casting liquid penetrate into the woven cloth, and then enter the coagulation bath for phase separation to form a flat membrane with a porous membrane layer (water treatment separation membrane layer), a bonding layer, and a support layer arranged in sequence, and then roll it into a cylindrical roll membrane.

[0069] The above scheme is further described below in conjunction with specific embodiments; it should be understood that these embodiments are used to illustrate the basic principles, main features and advantages of the present invention, and the present invention is not limited to the scope of the following embodiments; the implementation conditions adopted in the embodiments can be further adjusted according to specific requirements, and the implementation conditions not specified are usually the conditions in conventional experiments.

[0070] Unless otherwise specified in the following examples, all raw materials are commercially available or prepared by conventional methods in the art.

[0071] Example 1

[0072] This example provides a lined water treatment membrane and a preparation method thereof. Figures 1 to 3As shown, the liner water treatment membrane 100 includes a liner substrate with a porous structure and a water treatment separation membrane layer 120 arranged on the liner substrate; the liner substrate includes a support layer and a bonding layer, the support layer includes a liner structure 112 composed of first fiber filaments 111, the bonding layer includes a barrier area 114 formed by the first fiber filaments 111 and the second fiber filaments 113 being arranged alternately with each other, and the first fiber filaments in the barrier area 114 are at least partially the first fiber filaments in the liner structure 112;

[0073] The diameter of the first fiber filament 111 is greater than the diameter of the second fiber filament 113, and a plurality of pits 1131 are formed on the second fiber filament 113, and the plurality of pits are randomly distributed on the surface of the fiber filament; the water treatment separation membrane layer 120 has a partial area located in the barrier area 114, and the partial area is respectively in contact with the first fiber filament and the second fiber filament in the barrier area 114;

[0074] The first fiber filament 111 is PP polypropylene fiber with a diameter of 0.5 mm; the second fiber filament 113 is PET polyester fiber with a fineness of 600D; in the lining base, the number ratio of the first fiber filament to the second fiber filament is 1:2;

[0075] The lining substrate is a woven cloth structure, the lining structure has two bonding layers respectively located on the upper and lower surfaces of the supporting layer, the lining structure has two water treatment separation membrane layers corresponding to the bonding layers, and the lining structure does not contact the water treatment separation membrane layers.

[0076] The preparation method of the lined water treatment membrane comprises:

[0077] (1) Select commercially available PET polyester fiber and soak it in 8% hydrochloric acid for 1.5 h, controlling the soaking temperature to about 75° C.;

[0078] Then soak in an 8% sodium hydroxide aqueous solution for 1.5 hours, and control the soaking temperature to about 75°C;

[0079] After soaking, wash with clean water and dry it as the second fiber yarn for later use;

[0080] A woven cloth with a thickness of 1 mm woven from the first fiber yarn and the second fiber yarn is used as the lining base;

[0081] (2) Using the above-mentioned method 2, a casting solution (comprising 15% PVDF, 60% DMAC and 25% PEG by weight) was cast on both sides of the woven fabric, and the film was scraped with a scraper to a uniform thickness (about 0.1 mm), and then left in the air for 100 s to form an intermediate;

[0082] (3) Then the intermediate is immersed in deionized water in a coagulation bath for 300 seconds to form a lining water treatment membrane. Figure 3 This is a cross-sectional electron microscope image of the prepared lined water treatment membrane.

[0083] Example 2

[0084] This example provides a lined water treatment membrane and a preparation method thereof, which is basically the same as Example 1, except that the lining base is a knitted tube structure with a diameter of 1.95 mm, and the lined water treatment membrane is prepared using the above-mentioned form 1 method.

[0085] See also Figure 4 The lined water treatment membrane 100 in the form of a hollow fiber membrane has a porous membrane layer (water treatment separation membrane layer 120) on the cylindrical surface, a barrier zone 114 in the middle, a lining structure 112 inside, and a hollow structure 115 in the middle.

[0086] Figure 5 This is a cross-sectional electron micrograph of the prepared hollow fiber membrane-lined water treatment membrane.

[0087] Comparative Example 1

[0088] This example provides a lined water treatment membrane and a preparation method thereof, which is basically the same as Example 2, except that commercially available PET fibers made of PET polyester material are directly used as the second fiber filaments without acid-base etching treatment.

[0089] Application Experiment

[0090] The hollow fiber membrane-lined water treatment membranes obtained in Example 2 and Comparative Example 1 were subjected to a water treatment experiment. The aerobic tank water quality of the biochemical effluent of chemical wastewater (the sludge concentration containing bacterial colonies was about 8000±200 mg / L) was tested to compare the water production and water quality of the two.

[0091] use Figure 6 The experimental device shown in the figure includes a water inlet box 200, a water inlet pump 300, a water inlet valve 400, a return pipe 500 and a processing chamber 600. The water inlet box 200, the water inlet pump 300, the water inlet valve 400 and the processing chamber 600 are connected in sequence, and the two ends of the return pipe 500 are respectively connected to the processing chamber 600 and the water inlet box 200, and the lining water treatment membrane 100 is placed in the processing chamber 600. The water to be filtered in the water inlet box is pumped into the filter shell filled with the lining water treatment membrane by the water inlet pump, and after being filtered by the lining water treatment membrane, the water is discharged from the lower end of the inner hole of the lining water treatment membrane in the form of a hollow fiber membrane.

[0092] For detailed results, see Figure 7-10 As shown, Figure 7 and Figure 8 This is a statistical curve of the water flow rate and turbidity of the water produced by the hollow fiber membrane-lined water treatment membrane in Example 1. Fig. 9 and Fig.10It is a statistical curve diagram of the produced water flow rate and produced water turbidity of the lining water treatment membrane in the form of a hollow fiber membrane in Example 2. The test was started after a 1×1mm incision was made on the surface of the lining water treatment membrane at the same time stage. It can be seen that the produced water volume of the lining water treatment membrane using comparative example 1 was significantly improved and continued to rise until it stabilized at an increase of about 10%. At the same time, the turbidity also increased, and it has been in a high turbidity state since then; while using the lining water treatment membrane of Example 2 of the present invention, it can be clearly seen that the produced water volume and turbidity began to decline after being maintained at a high level for a period of time, and finally returned to the initial level within about 3 hours, indicating that the lining water treatment membrane of the present invention has self-repairing ability.

[0093] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

[0094] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

Claims

1. A lined water treatment membrane, characterized in that: The lining water treatment membrane comprises a lining substrate having a porous structure and a water treatment separation membrane layer arranged on the lining substrate; The lining substrate comprises a supporting layer and a bonding layer, wherein the supporting layer comprises a lining structure composed of first fiber filaments, and the bonding layer comprises a barrier region formed by mutually staggered arrangement of first fiber filaments and second fiber filaments, wherein at least part of the first fiber filaments in the barrier region are the first fiber filaments in the lining structure; The diameter of the first fiber filament is greater than the diameter of the second fiber filament, and a plurality of pits are formed on the second fiber filament; The water treatment separation membrane layer has a partial area located in the barrier area, and the partial area is in contact with the first fiber filaments and the second fiber filaments in the barrier area respectively.

2. The lined water treatment membrane according to claim 1, characterized in that: The diameter of the first fiber filament is 0.5-4 mm; and / or the fineness of the second fiber filament is 300D-1200D.

3. The lined water treatment membrane according to claim 1, characterized in that: The specific surface area of ​​the second fiber filaments is 2000-5000 square meters per cubic meter; and / or, the binding layers have two layers and are respectively located on the upper and lower surfaces of the support layer, and the water treatment separation membrane layers have two layers and correspond one to one with the binding layers.

4. The lined water treatment membrane according to claim 1, characterized in that: The material of the first fiber filament includes one or more combinations selected from polyamide, polypropylene, polycarbonate, and polybutylene succinate; and / or the material of the second fiber filament includes one or more combinations selected from polyester, polyvinyl alcohol, and polyacrylonitrile.

5. The lined water treatment membrane according to claim 1, characterized in that: The lining base is a knitted tube or a woven cloth; and / or, the lining base is formed by weaving the first fiber filaments and the second fiber filaments through a weaving method.

6. The lined water treatment membrane according to claim 1, characterized in that: The thickness of the lining substrate is 0.5-2 mm; and / or the thickness of the water treatment separation membrane layer is 0.06-0.15 mm.

7. The lined water treatment membrane according to claim 1, characterized in that: In the lining substrate, the ratio of the number of the first fiber filaments to the number of the second fiber filaments is 1:2-3; and / or the lining structure is not in contact with the water treatment separation membrane layer.

8. A method for preparing a lined water treatment membrane according to any one of claims 1 to 7, characterized in that: The preparation method comprises: (1) Spinning a first fiber filament and a second fiber filament into a lining substrate having a porous structure by a textile process; wherein the second fiber filament is a fiber filament having a plurality of pits formed by one or more physical and / or chemical treatments; (2) applying a water treatment separation membrane casting solution onto the inner lining substrate and allowing it to remain in the air to form an intermediate; (3) Placing the intermediate in a coagulation bath to form a lining water treatment membrane.

9. Use of the lined water treatment membrane according to any one of claims 1 to 7 in water treatment.

10. The use according to claim 9, characterized in that: During the water treatment process, the lining water treatment membrane is placed in a water body to be treated which contains aerobic bacteria or anaerobic bacteria and selectively contains sludge.

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