Anti-deformation water filtration spiral-wound membrane element with membrane folded once

Abstract

The utility model relates to the technical field of membrane elements, in particular to an anti-deformation water filtration spiral-wound membrane element with a single-folded membrane, which comprises a central tube, a first pure water separation net and a plurality of second pure water separation nets, wherein one side of the first pure water separation net is fixedly connected to the side surface of the central tube; the first pure water separation net and the second pure water separation nets are sequentially wound on the outer surface of the central pipe from bottom to top; film bags are arranged between the first pure water separation net and the second pure water separation net at the bottommost layer, between every two adjacent second pure water separation nets and on the upper surface of the second pure water separation net at the topmost layer; the membrane bag comprises a membrane which is folded, and functional layers are arranged on the opposite inner side faces of the membrane. A concentrated water separation net is laid between the two layers of folded membranes; the supporting cloth is laid on the upper surface and the lower surface of the membrane; according to the utility model, the performance stability of the polyolefin base material spiral-wound membrane element under high pressure can be improved, and the membrane is only folded once, so that the damage to the membrane is reduced.

Description

Technical Field

[0001] This utility model relates to the field of membrane element technology, and in particular to a deformation-resistant spiral wound water filtration membrane element with a single-fold membrane sheet. Background Technology

[0002] Membrane materials are a key factor determining the cost of membrane modules. Despite continuous advancements in production processes and manufacturing technologies, the cost of membrane materials remains high unless there are breakthroughs in existing technological frameworks. To overcome the traditional "non-woven fabric + polysulfone support layer + separation layer" membrane material structure, a novel "polyolefin support layer + separation layer" membrane material has been developed, achieving a significant cost reduction. However, polyolefin-based membrane elements manufactured using conventional methods deform under high pressure, affecting permeate flux. Furthermore, with increasing water treatment volumes, severe scaling can damage the functional layers of the polyolefin-based membrane, leading to a decrease in the overall performance of the membrane element.

[0003] To address the aforementioned problems, CN214681061U discloses a spiral wound membrane element and a filtration device. The spiral wound membrane element covers both sides of a pure water separator by reciprocating folding of the membrane sheet, and then a porous support layer is inserted between the membrane sheet and the pure water separator. CN219615289U discloses a water treatment membrane element that alleviates the above problems by placing at least two layers of pure water separators between the folded membrane sheets, with the grooved surfaces of the pure water separators facing each other.

[0004] CN214681061U discloses a spiral wound membrane element and a filtration device. Its main drawback is that the membrane needs to be folded back and forth. In addition to easily causing membrane damage and folding problems, the production process is also cumbersome, resulting in a significant reduction in the element yield and winding efficiency.

[0005] CN219615289U discloses a water treatment membrane element. Although this invention avoids direct contact between the pure water separator groove surface and the membrane, the membrane still deforms in practical applications because the back side of the pure water separator groove is still non-planar and its flexibility differs greatly from that of the polyolefin substrate membrane. This fails to completely solve the problems caused by deformation.

[0006] Therefore, in order to address the above problems, this utility model urgently needs to provide a deformation-resistant spiral wound water filtration membrane element with a single-fold membrane sheet. Utility Model Content

[0007] The purpose of this invention is to provide a deformation-resistant spiral wound water filtration membrane element with a single-fold membrane sheet. By folding the membrane sheet only once, this invention solves the problems of membrane damage, poor sealing, and low winding efficiency caused by repeated folding of the membrane sheet in the prior art.

[0008] A deformation-resistant spiral wound water filtration membrane element with a single-fold membrane sheet includes a central tube with multiple pure water collection holes on its side surface; it also includes a first pure water separator fixed to one side of the central tube and multiple second pure water separators welded in a stepped manner to the upper surface of the first pure water separator; the first pure water separator and each of the second pure water separators are wound sequentially from bottom to top around the outer surface of the central tube.

[0009] A membrane bag is installed between the first pure water separator and the bottom second pure water separator, between each adjacent second pure water separator, and on the upper surface of the top second pure water separator. The membrane bag includes a folded membrane sheet with a functional layer on the opposite inner side of the membrane sheet. A concentrate separator is laid between the two folded membrane sheets. It also includes a support cloth laid on the upper and lower surfaces of the membrane sheet. The membrane sheet, the concentrate separator, and the support cloth are fixed together along one side of the fold of the membrane sheet.

[0010] Each membrane, concentrate separator, support cloth, first pure water separator, and second pure water separator has the same length along the central tube; each membrane and support cloth is bonded and fixed to the corresponding first or second pure water separator.

[0011] Furthermore, the distance between the side of the bottommost second pure water separator used to connect with the first pure water separator and the side of the first pure water separator used to connect with the side surface of the central tube is greater than the outer circumference of the cross-section of the central tube.

[0012] Furthermore, the diaphragm, concentrate separator, and support fabric are fixed together using staples or a welding machine.

[0013] Furthermore, each diaphragm and support cloth is bonded and fixed to the corresponding first or second pure water separator using polyurethane adhesive.

[0014] Furthermore, the membrane material is a polyolefin-based ultrafiltration membrane, a polyolefin-based nanofiltration membrane, or a polyolefin-based reverse osmosis membrane.

[0015] Furthermore, the thickness of the membrane is 5-40 micrometers, and the width is 200-1500 mm.

[0016] Furthermore, the material of the support fabric is one of the following: spunbond nonwoven fabric, meltblown nonwoven fabric, needle-punched nonwoven fabric, spunlace nonwoven fabric, hot melt bonded nonwoven fabric, hot rolled nonwoven fabric, wet-laid nonwoven fabric, and woven fabric.

[0017] Furthermore, the contact angle of the support fabric is less than 90°, the air permeability is greater than 2000L / ㎡ / s, the thickness is 10-150μm, and the flux is greater than 400LMH; the thickness of the concentrate separator is 0.33-1.17mm.

[0018] Furthermore, the spacing between the staples or weld points of the fixing diaphragm, the concentrate separator, and the support fabric is 200-1000mm.

[0019] Furthermore, the direction of the staples fixing the diaphragm, the concentrate separator, and the support fabric is perpendicular to the fold direction of the diaphragm.

[0020] The single-folded membrane sheet anti-deformation spiral wound water filtration membrane element provided by this utility model has the following advantages compared with the prior art:

[0021] 1. The single-fold membrane anti-deformation spiral wound water filtration membrane element provided by this utility model involves folding the membrane once so that the functional layers come into contact with each other. A concentrate separator is placed inside the folded membrane, and two support fabrics are placed on the upper and lower surfaces of the folded membrane. The arranged membrane, concentrate separator, and support fabrics are then fixed to form a membrane bag. A certain number of membrane bags are then made as needed and placed between welded pure water separators, then bonded and wound. This utility model avoids the tedious repetitive folding of the membrane by using a single-folding method, reducing membrane damage and wrinkling / stacking, thus improving the yield of the element. Furthermore, the manufacturing process of this utility model is simple and convenient, can be completed using equipment, and avoids the tedious repetitive folding of the membrane, improving winding efficiency and enabling mass production.

[0022] 2. This utility model uses a high-density, high-permeability, and low-cost support cloth as the support for the membrane, which can effectively alleviate the membrane deformation caused by the pure water separator under high pressure and improve the performance stability of the spiral wound membrane element under high pressure. Attached Figure Description

[0023] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram (three-dimensional view) of the deformation-resistant spiral wound water filtration membrane element with a single-folded membrane sheet as described in this utility model.

[0025] Figure 2 This is a schematic diagram of the installation of the first pure water separator and the second pure water separator in this utility model.

[0026] Explanation of reference numerals in the attached figures:

[0027] 1. Membrane; 2. Supporting fabric; 3. Concentrate separator; 4. First pure water separator; 5. Central tube; 6. Second pure water separator. Detailed Implementation

[0028] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0029] In the description of this utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0030] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0031] like Figure 1 , Figure 2 As shown, the present invention provides a deformation-resistant spiral-wound water filtration membrane element with a single-fold membrane sheet, including a central tube 5, with multiple pure water collection holes on the side surface of the central tube 5; it also includes a first pure water separator 4 fixed to one side of the side surface of the central tube 5 and multiple second pure water separators 6 welded in a stepped manner to the upper surface of the first pure water separator 4; the first pure water separator 4 and each of the second pure water separators 6 are wound sequentially from bottom to top around the outer surface of the central tube 5;

[0032] A membrane bag is installed between the first pure water separator 4 and the bottommost second pure water separator 6, between each adjacent second pure water separator 6, and on the upper surface of the topmost second pure water separator 6. The membrane bag includes a folded membrane sheet 1, with functional layers on the opposite inner surfaces of the membrane sheet 1. A concentrate separator 3 is laid between the two folded membrane sheets 1. The membrane bag also includes a support cloth 2 laid on the upper and lower surfaces of the membrane sheet 1. The membrane sheet 1, the concentrate separator 3, and the support cloth 2 are fixed together along one side of the fold of the membrane sheet 1.

[0033] Each membrane 1, concentrate separator 3, support cloth 2, first pure water separator 4 and second pure water separator 6 have the same length along the central tube 5; each membrane 1 and support cloth 2 are respectively bonded and fixed to the corresponding first pure water separator 4 or second pure water separator 6.

[0034] 1. The single-fold membrane anti-deformation spiral-wound water filtration membrane element provided by this utility model involves folding the membrane 1 once so that the functional layers come into contact with each other after folding. Then, a concentrated water separator 3 is placed inside the folded membrane 1, and two support fabrics 2 are placed on the upper and lower surfaces of the outside of the folded membrane 1. The arranged membrane 1, concentrated water separator 3, and support fabrics 2 are fixed to form a membrane bag. Then, a certain number of membrane bags are made as needed, and they are placed between the welded pure water separators and bonded and wound around the outside of the central tube 5. This utility model avoids the tedious operation of repeatedly folding the membrane 1 by adopting a single-folding scheme, which reduces damage to the membrane 1 and the phenomenon of wrinkles and stacking of the membrane, thus improving the yield of the element. On the other hand, the preparation process of this utility model is simple and convenient and can be completed by equipment. It also avoids the tedious operation of repeatedly folding the membrane 1, improves the winding efficiency, and can achieve mass production.

[0035] 2. This utility model uses a support cloth 2 with high density, good water permeability and low cost as the support for the membrane 1, which can effectively alleviate the deformation of the membrane 1 caused by the pure water separator under high pressure and improve the performance stability of the spiral wound membrane element under high pressure.

[0036] In this embodiment, the distance between the side of the bottommost second pure water separator 6 that is connected to the first pure water separator 4 and the side of the first pure water separator 4 that is connected to the side surface of the central tube 5 is greater than the outer circumference of the cross-section of the central tube 5.

[0037] In this embodiment, the diaphragm 1, the concentrate separator 3, and the support cloth 2 are fixed together by staples or a welding machine.

[0038] In this embodiment, each diaphragm 1 and support cloth 2 are respectively bonded and fixed to the corresponding first pure water separator 4 or second pure water separator 6 by polyurethane adhesive.

[0039] In this embodiment, the membrane 1 is made of polyolefin-based ultrafiltration membrane, polyolefin-based nanofiltration membrane, or polyolefin-based reverse osmosis membrane.

[0040] In this embodiment, the thickness of the diaphragm 1 is 5-40 micrometers and the width is 200-1500 mm.

[0041] In this embodiment, the material of the support fabric 2 is one of spunbond nonwoven fabric, meltblown nonwoven fabric, needle-punched nonwoven fabric, spunlace nonwoven fabric, hot melt bonded nonwoven fabric, hot rolled nonwoven fabric, wet nonwoven fabric, and woven fabric.

[0042] In this embodiment, the contact angle of the support cloth 2 is less than 90°, the air permeability is greater than 2000L / ㎡ / s, the thickness is 10-150μm, and the flux is greater than 400LMH; the thickness of the concentrate separator 3 is 0.33-1.17mm.

[0043] In this embodiment, the distance between the staples or weld points of the fixing diaphragm 1, the concentrated water separator 3 and the support cloth 2 is 200-1000mm.

[0044] In this embodiment, the direction of the staples fixing the diaphragm 1, the concentrated water separator 3, and the support cloth 2 is perpendicular to the fold direction of the diaphragm 1.

[0045] The embodiments of this utility model include the following steps:

[0046] 1) Prepare a central tube 5 with multiple pure water collection holes spaced through its outer surface, multiple pure water separators, multiple support cloths 2, multiple membranes 1, and multiple concentrate separators 3;

[0047] 2) Divide the pure water separator into one first pure water separator 4 and multiple second pure water separators 6. Take the first pure water separator 4 and fix one side edge of the first pure water separator 4 to the side surface of the central tube 5 along the generatrix of the central tube 5; connect each of the second pure water separators 6 as follows: Figure 2 As shown, the components are welded in a stepped manner above the first pure water mesh 4.

[0048] 3) Take a membrane sheet 1 and fold the functional layer of the membrane sheet 1 inward; take a concentrate separator 3 and place it horizontally inside the two folded membrane sheets 1; take two support cloths 2 and place them horizontally on the top and bottom of the membrane sheet 1 respectively; fix the membrane sheet 1, support cloth 2 and concentrate separator 3 along one side of the fold of the membrane sheet 1 to obtain a membrane bag; repeat the above steps to obtain membrane bags corresponding to the number of pure water separators.

[0049] 4) Place a membrane bag between the first pure water separator 4 and the bottommost second pure water separator 6, apply adhesive to the top of the membrane bag, and then cover the bottommost second pure water separator 6 on top of the membrane bag; repeat the above steps of placing membrane bags, applying adhesive, and covering the second pure water separator 6 until the topmost second pure water separator 6 is covered on top of the membrane bag. Since the total number of membrane bags and pure water separators is the same, that is, the number of membrane bags is 1 greater than the total number of second pure water separators 6, there is one membrane bag left. Place the last membrane bag on top of the topmost second pure water separator 6.

[0050] 5) Apply adhesive to the upper surface of the top membrane bag, roll the central tube 5 upwards towards the first pure water separator 4, so that the lower surface of the first pure water separator 4 is attached to the upper surface of the top membrane bag. Wrap each membrane bag, the first pure water separator 4 and each second pure water separator 6 around the outside of the central tube 5. After curing, cut each membrane sheet 1, concentrate separator 3, support cloth 2, first pure water separator 4 and second pure water separator 6 along the length of the central tube 5 according to the required length, so that each membrane sheet 1, concentrate separator 3, support cloth 2, first pure water separator 4 and each second pure water separator 6 are of the same length along the central tube 5. At this time, the adhesive will bond each pure water separator to the two adjacent support cloths 2, and isolate the pure water separator from the liquid to be filtered, thus obtaining the deformation-resistant spiral wound water filter membrane element of the present invention with a single folded membrane sheet.

[0051] The single-fold membrane anti-deformation spiral wound water filter element obtained by this utility model, due to the isolation of the adhesive layer, allows sewage to flow only into the gap between the unbonded membrane 1 and the concentrated water separator 3. After being filtered by the membrane 1, it enters the first pure water separator 4 and each of the second pure water separators 6 through the support cloth 2, and then enters the central tube 5 through multiple pure water collection holes opened on the side surface of the central tube 5, thus obtaining pure water.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A deformation-resistant spiral wound water filtration membrane element with a single-folded membrane sheet, characterized in that: It includes a central tube (5), and a plurality of pure water collection holes are provided on the side surface of the central tube (5); it also includes a first pure water mesh (4) fixed to one side of the side surface of the central tube (5) and a plurality of second pure water meshes (6) welded in a stepped manner to the upper surface of the first pure water mesh (4); the first pure water mesh (4) and each of the second pure water meshes (6) are wound around the outer surface of the central tube (5) from bottom to top; A membrane bag is installed between the first pure water separator (4) and the bottom second pure water separator (6), between each adjacent second pure water separator (6), and on the upper surface of the top second pure water separator (6); the membrane bag includes a folded membrane sheet (1), and a functional layer is provided on the opposite inner side of the membrane sheet (1); a concentrate separator (3) is laid between the two folded membrane sheets (1); it also includes a support cloth (2) laid on the upper and lower surfaces of the membrane sheet (1); the membrane sheet (1), the concentrate separator (3) and the support cloth (2) are fixed together along one side of the fold of the membrane sheet (1); Each membrane (1), concentrated water separator (3), support cloth (2), first pure water separator (4) and second pure water separator (6) are of the same length along the central tube (5); each membrane (1) and support cloth (2) are respectively bonded and fixed to the corresponding first pure water separator (4) or second pure water separator (6).

2. The single pleated deformation-resistant water filtration spiral-wound membrane element of claim 1, wherein: The distance between the side of the bottom second pure water mesh (6) used to connect with the first pure water mesh (4) and the side of the first pure water mesh (4) used to connect with the side surface of the central tube (5) is greater than the outer circumference of the cross-section of the central tube (5).

3. The single pleated deformation-resistant water filtration spiral-wound membrane element of claim 2, wherein: The diaphragm (1), the concentrated water separator (3), and the support cloth (2) are fixed together by staples or welding machine.

4. The single pleated deformation-resistant water filtration spiral-wound membrane element of claim 3, wherein: Each diaphragm (1) and support cloth (2) are respectively bonded and fixed to the corresponding first pure water separator (4) or second pure water separator (6) by polyurethane adhesive.

5. The single pleated membrane element of claim 4, wherein: The membrane (1) is made of polyolefin-based ultrafiltration membrane, polyolefin-based nanofiltration membrane or polyolefin-based reverse osmosis membrane.

6. The single pleated membrane element of claim 5, wherein: The thickness of the membrane (1) is 5-40 micrometers and the width is 200-1500 mm.

7. The single pleated membrane abuse resistant water filtration cartridge of claim 6 wherein: The material of the support fabric (2) is one of the following: spunbond nonwoven fabric, meltblown nonwoven fabric, needle-punched nonwoven fabric, spunlace nonwoven fabric, hot melt bonded nonwoven fabric, hot rolled nonwoven fabric, wet nonwoven fabric and woven fabric.

8. The single pleated membrane abuse resistant water filtration cartridge of claim 7, wherein: The contact angle of the support fabric (2) is less than 90°, the air permeability is greater than 2000L / ㎡ / s, the thickness is 10-150μm, and the flux is greater than 400LMH; the thickness of the concentrate separator (3) is 0.33-1.17mm.

9. The single pleated membrane abuse resistant water filtration cartridge of claim 8, wherein: The spacing between the staples or weld points of the fixed diaphragm (1), the concentrated water separator (3), and the support cloth (2) is 200-1000mm.

10. The deformation-resistant spiral wound water filtration membrane element with a single-folded membrane sheet according to claim 9, characterized in that: The direction of the staples fixing the diaphragm (1), the concentrated water separator (3) and the support cloth (2) is perpendicular to the fold direction of the diaphragm (1).

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