JPH04131412U - cartridge filter - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the filtration accuracy of a cartridge filter for liquid filtration without impairing the filtration life. [Configuration] 0.5 on top of porous core tube or water permeable core tube
It is a cylindrical cartridge filter consisting of a non-woven fabric filtration layer made of ultra-fine fibers of denier or less, and a thread filtration layer with a cotton count of 0.5 to 5.0 ^S on top of the non-woven fabric filtration layer. The layer thickness ratio of the layers was set to nonwoven fabric filtration layer: thread filtration layer = 1:1 to 1:3. [Effect] A deep filtration effect is achieved in which solids with a relatively large particle size in the liquid to be filtered are collected by the thread filtration layer, and fine solids are collected by the non-woven fabric filtration layer, which improves the filtration life and filtration accuracy. improve.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a cylindrical cartridge type filter suitable for liquid filtration. It is something to do.

0002

[Conventional technology]

Cylindrical cartridge type filters are used in the pharmaceutical industry, electronic industry, etc. filtration of purified water, filtration or filtration in the alcoholic beverage manufacturing process in the food industry. is used in various fields such as filtration of paint materials in the automobile industry.

0003 For example, as a thread-wound type, spun yarn or woolen yarn is wound around a porous tube. A similar method is described in Japanese Utility Model Application Publication No. 12922/1983, in which heat-adhesive composite fibers are made into a cylindrical shape. A molded product is described in Japanese Patent Publication No. 53-43709, and there are other There is one in which Panbond nonwoven fabric is wrapped around a perforated tube.

0004

[Problems that the idea should solve]

A spool-type cartridge with spun yarn or woolen yarn wrapped around a conventional porous tube. Although filters have the advantage of relatively low product cost, There is a risk that some of the fibers that form the thread will fall off, and these fallen fibers may be mixed into the filtrate. There is a It is not suitable for high-precision filtration.

[0005] Cartridge filters made of heat-adhesive fibers formed into a cylindrical shape have a porous core material. It has the advantage that no fibers are needed and the fibers are bonded so there is no chance of fibers falling off. . However, the filtration accuracy of a filter is generally determined by the thickness of the fiber material used. high precision in thermal adhesive fiber molded cartridge filters. A uniform web made of fine fibers is required to make filters of high quality. Mass production is difficult in terms of productivity, cost, and quality.

[0006] It is difficult to make fine fibers with spunbond nonwoven fabrics, and high-precision filtration is difficult. Melt-blown nonwoven fabrics have fine fibers, but the fiber strength is weak. There is a risk that fallen fibers may be mixed into the filtrate.

[0007]

[Means for ideas to solve problems]

The present invention involves winding a nonwoven fabric containing at least 50% by weight of ultrafine fibers with a fineness of 0.5 denier or less on a water-permeable core tube, such as a porous core tube or a fiber-molded core tube, and further wrapping the nonwoven fabric on the nonwoven fabric. A nonwoven fabric filtration layer and a yarn filtration layer are formed by winding a spun yarn or woolen yarn with a cotton count of 0.5 to 5 ^S made of fibers having a fineness greater than 0.5 denier, and the nonwoven fabric filtration layer and the yarn filtration layer are The thickness ratio of the thread filtration layer is set to 1:1 to 1:3 in the cross section of the cartridge filter, providing a deep filtration function and improving the filtration life, as well as preventing the incorporation of fibers falling from the thread layer into the filtrate. The structure is designed to prevent this and further improve the high-precision filtration effect by the ultrafine fiber nonwoven fabric layer.

[0008] The porous core tube can be made of plastic such as polypropylene, metal, or ceramic. You can use any material such as plastic, but from the cost point of view, plastic material such as polypropylene can be used. Molded articles made of ticks are preferred. The size and shape should match the size and type of the filtration device. You can make it. For example, the size of the hole can be a rectangle with an angle of 3 to 5 mm. can. In addition, as a water-permeable core tube such as a fiber-molded core tube, for example, a thermally adhesive component can be used. It is composed of fibers containing heat-adhesive single fibers, parallel type or core-sheath type. Adhesive conjugate fibers alone or blended with non-thermal adhesive fibers may be used. thermal adhesive The melting points of the high melting point component of the composite fiber and the non-thermally adhesive fiber component are different from those of the low melting point component of the thermally adhesive composite fiber. It is preferable that the temperature is 20° C. or more higher than the melting point of the point component and the heat-adhesive single fiber component.

[0009] The fiber components forming the above-mentioned water-permeable core tube include natural fiber components such as cotton and linen, and Synthesis of semi-synthetic fiber components such as yong, polyolefin, polyester, polyamide, etc. It may be selected as appropriate from among the fiber components. The cylindrical filtration layer is made by processing the above fibers using a carding machine. The material should be made into a card web, and should not be heated above the temperature of the low melting point component and below the temperature of the high melting point component. A method of winding the fibers into a cylindrical shape, or filling the above fibers into a cylindrical container and heating them at the above temperature. An example of this method is heat molding.

0010 50 layers of fibers of 0.5 denier or less are placed on the porous core tube or water permeable core tube. Wrap a nonwoven fabric containing % or more. Fibers of 0.5 denier or less are split type composites. It can be obtained by splitting the fibers. As a constituent component, for example, poly Ethylene, polypropylene, poly4-methylpentene-1, ethylene-vinylene Polyolefin polymers such as alcohol copolymers and ethylene-vinyl acetate copolymers Or copolymer, polyethylene terephthalate, polybutylene terephthalate Polyester polymers or copolymers such as nylon 6, nylon 66, nylon Select as appropriate from polyamide polymers or copolymers such as Ron 12. However, it is not limited to the above. In addition, various cross-sectional shapes of fibers can be considered, Although not particularly limited, a radial type is preferred.

[0011] The above fibers can be processed by carding method, cross layer method, random Weber method, wet paper making method, Non-woven fabrics are made using dry or wet heat bonding, needle punching, high pressure liquid flow, etc. , If the division is insufficient at this point, further treatment such as needle punch treatment, high pressure liquid flow treatment, and super Apply treatment such as sonication. In addition, less than 50% by weight of other fibers are mixed into the nonwoven fabric. However, other fibers include natural fibers, semi-synthetic fibers, and synthetic fibers as described above. It can be appropriately selected from fibers.

0012 The fabric weight and wrapping amount of the nonwoven fabric can be determined depending on the intended use, but the The thickness of the nonwoven fabric layer in the cross section of the difilter should not be larger than the thread layer. That is, it is preferable that the nonwoven fabric layer thickness: yarn layer thickness = 1:1 to 1:3. Nonwoven layer thickness If it is made larger than the thread layer thickness, the filtration accuracy will improve, but this will lead to a decrease in the filtration life. Put it away. In addition, when the thickness of the nonwoven fabric layer is less than 1/3 of the thickness of the thread layer, the filtration life improves. However, high filtration accuracy cannot be expected.

[0013] Next, the cotton count 0.5 to ^5S spun yarn or woolen yarn to be wound on the nonwoven fabric layer is selected from natural fibers, semi-synthetic fibers, and synthetic fibers by ring spinning or parlock spinning. Obtainable. When the thickness of the thread is less than 0.5 ^S , the fiber density of the thread layer becomes coarse, the amount of large particles collected in the thread layer decreases, and the nonwoven fabric layer becomes clogged at an early stage. Moreover, if it is thinner than ^5S , the density of the thread layer becomes high and deep filtration cannot be expected, resulting in a decrease in the filtration life.

[0014]

[Effect]

The cartridge filter of this invention uses a combination of nonwoven fabric and yarn with a cotton count of 0.5 to 5 ^S , and the filtration layer of the yarn improves the filtration life by collecting only relatively large particles of the filtrate. The filtration layer of the nonwoven fabric used collects relatively small particles, improving filtration accuracy, and the previous thread filtration layer captures only relatively large particles, making the nonwoven fabric less likely to become clogged. As a result, filtration accuracy can be improved without impairing filtration life.

[0015]

【Example】

[Example 1] The fiber has a cross section (divided into 16) as shown in FIG. 1 copolymer was placed, melt composite extrusion spinning was performed, and after stretching, cutting was performed to obtain a split composite fiber (9) of 3 denier and 51 mm. This splittable conjugate fiber (9) was used in an amount of 100% by weight to form a carded web using a carding machine, and subjected to high-pressure liquid flow treatment three times on each side under a water pressure of 150 kg/cm ² to obtain a nonwoven fabric with a basis weight of 60 g/m ² . At this time, each component of the composite fiber (9) was divided into 0.19 denier pieces.

Next, using 100% by weight of polypropylene fibers of 2 denier and 76 mm as yarn, a yarn having a cotton count of 1.2 ^S and a twist number of 2.0 T/in was obtained by ring spinning.

[0017] Next, place the above on a polypropylene porous core tube (4) with an outer diameter of 32 mm and a length of 250 mm. Wrap the nonwoven fabric until the outer diameter is 47 mm (layer thickness 7.5 mm) to create a nonwoven filtration layer (3). And so. Furthermore, wrap the above thread on top of this until the outer diameter is 65 mm (layer thickness 9.0 mm). As shown in Figure 1, the ratio of the nonwoven fabric layer thickness to the yarn layer thickness is 1:1.2. This is a cartridge filter (1) that looks like this.

[Example 2] A fiber having a cross section as shown in FIG. 3 was prepared by melt composite extrusion spinning with polyethylene as the A component (7) in the diagram and polypropylene as the B component (8) in the diagram. After stretching, cutting was performed to obtain a core-sheath composite fiber (6) of 2 denier and 51 mm. A carded web using 100% by weight of this composite fiber (6) with a basis weight of 25 g/m ² was heat-treated with hot air at 140°C to melt the A component (7), and the length was 35 cm, the weight was 1.5 kg, The material was wound around an iron core with a diameter of 30 mm while applying pressure so that the fiber density was 0.3 g/cm ³ on average until the winding diameter reached 55 mm. After cooling, the iron core was extracted to form a water-permeable core tube (5). did.

[0019] The nonwoven fabric obtained in Example 1 was placed on the water-permeable core tube (5) with an outer diameter of 60 mm (layer thickness 2.5 mm). The thread obtained in Example 1 was further wrapped around the thread to form a non-woven filter layer with an outer diameter of 65 mm. (Layer thickness: 2.5 mm) to form a thread filtration layer, and the ratio between the nonwoven fabric layer thickness and the thread layer thickness is A cartridge filter (1) as shown in FIG. 2 with a ratio of 1:1 was made.

[0020] [Comparative Example 1] A layer of the nonwoven fabric of Example 1 with an outer diameter of 55 mm was placed on the porous core tube of Example 1. A nonwoven fabric filter layer was formed by wrapping the layer until the thickness reached 11.5 mm, and then the Example Wrap the thread obtained in step 1 to an outer diameter of 65 mm (layer thickness 5.0 mm) to form a thread filtration layer. A cartridge filter with a ratio of woven fabric layer thickness to yarn layer thickness = 1:0.4 was created.

[0021] Filtration properties of each cartridge filter of Example 1, Example 2 and Comparative Example 1 Table 1 shows the performance evaluation results.

[0022]

[Table 1]

[0023]The filtration performance was evaluated by the following method. Filtration life (I): A suspension of test dust (JIS 11 type, Kanto loam, average particle size 2 μm) adjusted to a concentration of 200 ppm is uniformly stirred and 10 liters is poured from the outside of each cartridge filter toward the hollow part. Evaluate by the total amount of water flow (l) when the water flow pressure to maintain min is 2.0 kg/cm ² . Initial filtration efficiency (%): Collect 1 liter of the above suspension, set the dust weight after drying as A, collect 1 liter of clean water 1 minute after starting filtration, set the dust weight after drying as B, and use the following formula. calculate. Initial filtration efficiency (%) = [(A-B)/A] x 100 Filtration accuracy (μm): The above-mentioned clean water was collected, and an ultracentrifugal automatic particle size distribution device (manufactured by Horiba, Ltd.) was used to remove narrow particles. The diameter was measured and taken as the maximum particle diameter.

[0024]

[Effect of the idea]

The cartridge filter of the present invention is made of a nonwoven fabric in which a nonwoven fabric containing at least 50% by weight of ultrafine fibers with a fineness of 0.5 denier or less is wound around a water permeable core tube such as a porous core tube or a fiber-molded core tube. A yarn filtration layer with a coarser fiber density than the nonwoven fabric filtration layer is formed by winding spun yarn or woolen yarn of a cotton count of 0.5 to 5 ^S , which is made of fibers thicker than 0.5 denier, around the outer periphery of the layer. The thickness ratio of the nonwoven fabric filtration layer and the thread filtration layer is 1:1 to 1:3 in the cross section of the cartridge filter, and the liquid to be filtered is directed from the outer surface toward the center. If applied to a filter that passes liquid through the filter, solids with a relatively large particle size in the liquid to be filtered will be collected in the thread filtration layer, and fine and ultrafine solids that have passed through the thread filtration layer will be collected. will be collected in the inner nonwoven fabric filtration layer, achieving a so-called deep filtration effect. Therefore, the filtration life becomes longer, the filter replacement cycle can be extended, and precision filtration can also be achieved.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway side view of a cartridge filter of the present invention.

FIG. 2 is a partially cutaway side view of the cartridge filter of the present invention.

FIG. 3 is a fiber cross-sectional view showing an example of a composite fiber.

FIG. 4 is a fiber cross-sectional view showing an example of a composite fiber.

[Explanation of symbols]

1 Cartridge filter 2 Thread filtration layer 3 Nonwoven fabric filtration layer 4 Porous core tube 5 Water-permeable core tube 6 Core-sheath type composite fiber 7 A component 8 B component 9 Splitable composite fiber 10 C component 11 D component

Continuing from the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location D04H 1/70 A 7199-3B

Claims (1)

[Scope of utility model registration request] Claim 1: A nonwoven fabric containing at least 50% by weight of ultrafine fibers with a fineness of 0.5 denier or less is wound around a water-permeable core tube such as a porous core tube or a fiber-molded core tube, and the nonwoven fabric A nonwoven fabric filtration layer and a thread filtration layer are formed by winding a spun yarn or woolen yarn of a cotton count of 0.5 to 5 ^S made of fibers having a fineness greater than 0.5 denier on top of the nonwoven fabric. A cartridge filter characterized in that the layer thickness ratio between the filtration layer and the thread filtration layer is 1:1 to 1:3 in a cross section of the cartridge filter.