A large-flux backwashable pleated filter element

Abstract

The utility model discloses a large-flux backwashable folded filter element, comprising an outer sleeve, a folded filter material and an inner sleeve arranged in sequence from the outside to the inside, and end caps connected to the outer sleeve and the inner sleeve, and located at both ends of the filter element. The folded filter material comprises a plastic net, a functional nanofiber microfiltration membrane and a non-woven fabric arranged in sequence from the outside to the inside along the water flow direction. The utility model has a high pressure bearing capacity, can withstand multiple cleanings, has the characteristics of large flow, high filtration efficiency and long service life, and can be used for nanofiltration or reverse osmosis pretreatment in the field of municipal water supply, and can also be used for large-flow water filtration in the food and beverage, biopharmaceutical and other industries.

Description

Technical Field

[0001] The utility model relates to a filter element, in particular to a filter element used for water treatment. Background Art

[0002] Traditional filter elements often sacrifice flow rate while pursuing high filtration efficiency. This results in that in some occasions where large flow rates are required, the filter element may not be able to meet the needs, or multiple filter elements need to be configured, increasing costs and space occupation.

[0003] In addition, the filter element will gradually become clogged during use, resulting in a smaller and smaller flow rate, and needs to be replaced or cleaned regularly. The replacement of the filter element is cumbersome and costly, which increases the burden on users.

[0004] At present, most of the filter elements on the market are disposable, and the replacement and disposal of filter elements often cause certain environmental pollution. In addition, the replacement of filter elements will cause the production system to stop production for a long time, which in turn increases costs. Utility Model Content

[0005] In order to solve the above problems, the utility model provides a large-flux backwashable pleated filter element, comprising an outer sleeve, a pleated filter material, an inner sleeve, and an end cover;

[0006] The outer sleeve, folded filter material and inner sleeve are arranged in sequence from outside to inside;

[0007] The end caps are connected to the outer sleeve and the inner sleeve and are located at both ends of the filter element;

[0008] The folded filter material has a W-shaped folded structure along the circumferential direction.

[0009] The folded filter material comprises a plastic net, a functional nanofiber microfiltration membrane and a non-woven fabric, and the plastic net, the functional nanofiber microfiltration membrane and the non-woven fabric are arranged in sequence from outside to inside along the water flow direction.

[0010] Preferably, the connection method between the end cover and the outer sleeve and the inner sleeve includes one of hot melt welding and expansion connection or a combination of the aforementioned methods.

[0011] Preferably, the material of the outer sleeve includes one of 304 stainless steel, 316L stainless steel, polypropylene, polytetrafluoroethylene, or a combination of the foregoing, and more preferably 304 stainless steel or 316L stainless steel.

[0012] Preferably, the inner walls of the outer sleeve and the inner sleeve are both provided with a plurality of penetrating water holes, and the water holes are distributed in an array at equal intervals along the axes of the outer sleeve and the inner sleeve on the inner walls of the outer sleeve and the inner sleeve.

[0013] Preferably, a rectangular drain port is provided at the connection between the outer sleeve and the end cover.

[0014] Preferably, a silicone sealing ring is provided on the end cover, an annular groove is provided on the end surface of the silicone sealing ring in contact with the filter element, and the ends of the outer sleeve and the inner sleeve are respectively inserted into the annular grooves.

[0015] Preferably, the number of pleats of the pleated filter material is >90, preferably >120, and more preferably >150.

[0016] Preferably, the filtration accuracy of the plastic net is 50-200 μm, preferably 50-150 μm, and more preferably 50-100 μm.

[0017] Preferably, the material of the functional nanofiber microfiltration membrane is polyvinylidene fluoride.

[0018] Preferably, the filtration flux of the functional nanofiber microfiltration membrane is 30-50 L / m 2 ·h.

[0019] Preferably, the surface of the functional nanofiber microfiltration membrane can completely absorb and wet water within 1 second, so that the contact angle between water and the material surface is rapidly reduced to 0°.

[0020] Preferably, the functional nanofiber microfiltration membrane has an average interception rate of NaCl aerosol medium of ≥95%.

[0021] Preferably, the average pore size of the functional nanofiber microfiltration membrane is 1 μm or 5 μm.

[0022] Preferably, the non-woven fabric is a calendered non-woven fabric.

[0023] Preferably, the nonwoven fabric has a grammage of 45 g / m 2 .

[0024] Preferably, the filtration accuracy of the non-woven fabric is 20 μm.

[0025] Preferably, the inner sleeve is made of 304 stainless steel or 316L stainless steel.

[0026] Preferably, the diameter ratio of the outer sleeve to the inner sleeve is (2-3):1, more preferably 2:1.

[0027] The beneficial effects of the utility model are:

[0028] The utility model provides a large-flux backwashable folded filter element, which is composed of an outer sleeve, a folded filter material, an inner sleeve, and an end cap. The end cap is connected to the outer sleeve and the inner sleeve and is located at both ends of the filter element. The utility model uses a plastic net for preliminary coarse filtration to remove larger particles and pollutants, while ensuring that the cleaning dirt of the functional nanofiber microfiltration membrane is easy to flow out with the flushing water flow; then the functional nanofiber microfiltration membrane in the folded filter material performs fine filtration to remove particles and pollutants larger than the pore size of the microfiltration membrane, protecting the subsequent nanofiltration membrane or reverse osmosis. The non-woven fabric in the folded filter material is used as a supporting material to enhance the stability of the structure, support the functional nanofiber microfiltration membrane, and ensure that the pleated part of the folded filter material is not easy to spread and form a series of flows. In addition, the utility model is supported by stainless steel inner and outer sleeves, so that the pressure bearing capacity of the filter element becomes stronger and will not be deformed. At the same time, the diameter ratio of the inner and outer sleeves is optimized to ensure the patency of water filtration. In addition, the connection between the outer sleeve and the end cap has a rectangular sewage outlet, which is conducive to the outflow of the folded filter material cleaning waste liquid, ensures the cleaning effect, and prolongs the service life of the filter element. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the utility model 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 of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 It is a cross-sectional view of the utility model.

[0031] Figure 2 It is a longitudinal sectional view of the utility model.

[0032] Figure 3 It is a three-dimensional diagram of the utility model.

[0033] Figure 4 This is a structural diagram of the filter material used in the present utility model.

[0034] The following are the descriptions of the reference numerals:

[0035] 1. Outer sleeve; 2. Folded filter material; 3. Inner sleeve; 4. End cover; 5. End cover; 6. Drain port. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0037] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0038] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the utility model.

[0040] The utility model proposes a large-flux backwashable folded filter element, which is supported by stainless steel inner and outer sleeves, so that the pressure bearing capacity of the filter element becomes stronger and will not be deformed; the functional nanofiber microfiltration membrane of the folded filter material effectively intercepts and removes pollutants in the water, and the non-woven fabric provides a supporting structure; at the same time, the diameter ratio of the inner and outer sleeves is optimized to ensure the smoothness of water filtration. In addition, the connection between the outer sleeve and the end cover has a rectangular sewage outlet, which is conducive to the outflow of waste liquid from the folded filter material, ensuring the cleaning effect and extending the service life of the filter element.

[0041] Specifically, Figure 1 As shown, the utility model provides a large flux backwashable pleated filter element, comprising an outer sleeve 1, a pleated filter material 2 and an inner sleeve 3 arranged in sequence from outside to inside. The pleated filter material 2 is a W-shaped pleated structure along the circumferential direction. Figure 2 As shown, the end cap 4 and the end cap 5 are connected to the outer sleeve 1 and the inner sleeve 3 by hot-melt welding, and are located at both ends of the filter element.

[0042] The diameter ratio of the outer sleeve 1 to the inner sleeve 3 is 2:1, which ensures the uniformity of the filtered water flow of the entire filter element.

[0043] The outer sleeve 1 and the inner sleeve 3 are both made of stainless steel of grade 304 or above, which ensures that the filter element has sufficient structural strength and is not easily deformed due to water pressure. At the same time, it also provides support for the filter material and improves the overall pressure-bearing capacity of the filter element.

[0044] Further, the inner walls of the outer sleeve 1 and the inner sleeve 3 are both provided with a plurality of penetrating, evenly arranged water holes. The water holes may be circular holes or polygonal holes. In this embodiment, hexagonal holes are used. In one embodiment, the plurality of water holes are arranged in an array at equal intervals along the axis of the outer sleeve 1 and the inner sleeve 3 on the inner walls of the outer sleeve 1 and the inner sleeve 3.

[0045] like Figure 3 As shown, the connection between the outer sleeve 1 and the end caps 4 and 5 is provided with a sewage outlet 6, which is conducive to the outflow of the waste liquid from the folded filter material cleaning, ensures the cleaning effect, and prolongs the service life of the filter element.

[0046] like Figure 4 As shown, the folded filter material 2 has a three-layer structure, specifically, it is composed of a plastic net, a functional nanofiber microfiltration membrane and a non-woven fabric, wherein the plastic net, the functional nanofiber microfiltration membrane and the non-woven fabric are arranged in sequence from outside to inside according to the water flow direction.

[0047] The number of pleats of the plastic net, functional nanofiber microfiltration membrane, and non-woven fabric is greater than 90, ensuring that the pleated parts are tight enough to prevent the high-pressure water flow from dispersing and forming cross-flow, affecting the filtration effect, while ensuring that the filter element has sufficient filtration area.

[0048] In a preferred embodiment, the filtration accuracy of the plastic net is 50 μm; the material of the functional nanofiber microfiltration membrane is polyvinylidene fluoride, and the filtration flux is 30-50 L / m 2 h, hydrophilicity is that the static contact angle drops to 0° within 1s, the average interception rate of aerosol NaCl medium is ≥95%, and the average pore size is 1μm or 5μm; the non-woven fabric is a calendered non-woven fabric with a gram weight of 45g / m 2 , the filtration accuracy is 20μm.

[0049] Filtration process:

[0050] The utility model is clamped inside the filter through the silicone sealing ring on the end cover;

[0051] When water flows through the filter, the water first flows through the outer sleeve 1 and enters the pleated filter material 2;

[0052] The outer plastic mesh of the folded filter material 2 performs pre-filtration to remove larger particles and pollutants, providing protection for the functional nanofiber microfiltration membrane;

[0053] Afterwards, the functional nanofiber microfiltration membrane performs fine filtration to remove particles and pollutants larger than the pore size of the microfiltration membrane (for example, particles and pollutants larger than 1 μm or 5 μm) to protect the subsequent nanofiltration membrane or reverse osmosis;

[0054] Finally, the water flows through the non-woven fabric, wherein the non-woven fabric of the folded filter material supports the functional nanofiber microfiltration membrane, ensuring that the folded filter material 2 is not easily deformed.

[0055] Cleaning process:

[0056] The cleaning liquid enters the contaminated surface of the pleated filter material 2 through the outer sleeve 1;

[0057] Since the effective filtration layer is the functional nanofiber microfiltration membrane layer of the folded filter material 2, the cleaning liquid can directly clean the functional nanofiber microfiltration membrane layer through the plastic net;

[0058] A drain port 6 is cut out at the connection between the outer sleeve 1 and the end cover to facilitate the cleaning liquid to enter the filter element. At the same time, when draining water, the cleaned pollutants are more likely to flow out through the drain port 6, preventing pollutants from accumulating in the dead corners of the filter element and affecting the filtering efficiency.

[0059] The utility model has significantly improved the pressure bearing capacity of the filter element, enhanced the filtering efficiency, and greatly improved the recovery effect after cleaning by optimizing the filter element structure and filter material composition. While ensuring high-precision filtering performance, the utility model realizes the processing capacity of large flow and backwashing function, thereby greatly extending the service life, effectively reducing the impact on high-demand scenes of continuous production, and reducing the cost of frequent replacement of filter elements. In addition to being suitable for nanofiltration or reverse osmosis pretreatment in the field of municipal water supply, the utility model can also be widely used in large-flow water filtration scenes in the food and beverage, biopharmaceutical and other industries, showing its wide applicability and practicality.

[0060] The above description is only a preferred embodiment of the utility model, and does not limit the patent scope of the utility model. All equivalent structural changes made by using the contents of the utility model specification and drawings under the utility model concept, or directly / indirectly used in other related technical fields are included in the patent protection scope of the utility model.

Claims

1. A large-flux backwashable pleated filter element, characterized in that: It includes an outer sleeve, a folded filter material, an inner sleeve and an end cover; The outer sleeve, folded filter material and inner sleeve are arranged in sequence from outside to inside; The end caps are connected to the outer sleeve and the inner sleeve and are located at both ends of the filter element; The folded filter material has a W-shaped folded structure along the circumferential direction. The folded filter material comprises a plastic net, a functional nanofiber microfiltration membrane and a non-woven fabric. The plastic net, the functional nanofiber microfiltration membrane and the non-woven fabric are arranged in sequence from outside to inside along the water flow direction.

2. The folded filter element according to claim 1, characterized in that: The connection method between the end cover and the outer sleeve and the inner sleeve includes one of hot melt welding and expansion connection or a combination of the above.

3. The folded filter element according to claim 1, characterized in that: The material of the outer sleeve includes one of 304 stainless steel, 316L stainless steel, polypropylene, polytetrafluoroethylene, or a combination of the above.

4. The folded filter element according to claim 1, characterized in that: The inner walls of the outer sleeve and the inner sleeve are both provided with a plurality of penetrating water holes, and the water holes are distributed in an array at equal intervals along the axes of the outer sleeve and the inner sleeve on the inner walls of the outer sleeve and the inner sleeve.

5. The folded filter element according to claim 1, characterized in that: The end cover is provided with a silicone sealing ring, the end surface of the silicone sealing ring in contact with the filter element is provided with an annular groove, and the ends of the outer sleeve and the inner sleeve are respectively inserted in the annular grooves.

6. The folded filter element according to claim 1, characterized in that: The number of pleats of the pleated filter material is greater than 90.

7. The folded filter element according to claim 1, characterized in that: The filtration accuracy of the plastic net is 50-200 μm.

8. The folded filter element according to claim 1, characterized in that: The material of the functional nanofiber microfiltration membrane is polyvinylidene fluoride, and the filtration flux is 30-50L / m 2 ·h, hydrophilicity is that the static contact angle drops to 0° within 1s, the average interception rate of aerosol NaCl medium is ≥95%, and the average pore size is 1μm or 5μm.

9. The folded filter element according to claim 1, characterized in that: The non-woven fabric is a calendered non-woven fabric with a gram weight of 45g / m 2 , the filtration accuracy is 20μm.

10. The folded filter element according to claim 1, characterized in that: The diameter ratio of the outer sleeve to the inner sleeve is (2-3):1.

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