JPH08206465A - Hollow yarn type cartridge filter - Google Patents

Abstract

PURPOSE: To allow a hollow yarn membrane bundle itself to hold the shape and to ensure a uniform flow of fluid by providing the space communicating with the linear part of the hollow yarn membrane bundle formed into a loop shape having a plurality of crossing points and respectively providing fluid passages in the vicinity of a bundled and fixed part and the loop part. CONSTITUTION: When a hollow yarn membrane bundle is produced, continuous hollow yarn membranes 1 are taken up by two rotary reels 2 having rod-shaped projections 7 provided thereto so as to cross the axial direction thereof at a right angle while lease is applied to the membranes by a traverser 3. By this taking-up, the rod-shaped projections 7 form the spaces communicating with a linear part 5 in loop parts 6. The hollow yarn membrane bundle thus produced is housed in a cylindrical container 13 in such a state that the open ends of the hollow yarn membranes are converged at one place and the open ends are bundled and fixed by a potting material 12. In the housing container 13, a large fluid passage 14 is formed in the vicinity of a loop part 16 and a small fluid passage 15 is formed in the vicinity of a potting part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow fiber membrane type cartridge filter used in a fluid separation device such as ultrafiltration and microfiltration. More specifically, a hollow fiber membrane bundle having a specific shape, which has a fluid passage for uniformly distributing a fluid in the hollow fiber membrane bundle, has a specific shape so as to further promote the uniformity of fluid flow. The present invention relates to a hollow fiber membrane type cartridge filter housed in a shaped container.

[0002]

2. Description of the Related Art A large number of hollow fiber membranes are bundled so that the flow of a fluid is uniform, and each hollow fiber membrane bundle has a plurality of intersections (hereinafter referred to as "crossing"). Penetration,
It is well known to be used for ultrafiltration, microfiltration, artificial dialysis, gas separation and the like. In reverse osmosis or gas separation, a relatively clean fluid that does not contain a substance that blocks the gaps between the hollow fiber membranes is usually processed, so a hollow fiber membrane bundle that is firmly and firmly bound is used. Ultrafiltration,
In artificial dialysis, plasma separation, artificial lung, etc., hollow fiber membrane bundles having both ends focused and fixed are used.

In the microfiltration device, a support member is provided to maintain the shape of the hollow fiber membrane bundle (Shokaisho 62-103).
No. 407, No. 62-103409, No. 1-9
No. 2203), a plurality of hollow fiber membrane bundles are arranged so as to intersect with each other by utilizing the fact that the diameter of the loop portion of the hollow fiber membrane bundle is larger than that of the linear portion (Actual Kaihei 4-
33927).

FIG. 7 shows a winding step in manufacturing a hollow fiber membrane bundle by a conventional method. The biaxial cassette 102 for winding the hollow fiber membrane 101 and a traverse for twilling. 103 is shown. In the loop part 104,
As is easily imagined, the hollow fiber membranes are in close contact with each other, making it more difficult for the fluid to pass through than the straight portion 105.

FIG. 8 shows a conventional so-called cartridge filter 110 in which the hollow fiber membrane bundle 111 as described above is bundled and fixed together with a porous tube 113 by a potting material 112. The fluid to be treated supplied from the inlet 121 of the filter housing 120 flows through the perforated tube 113 from the surface of the hollow fiber membrane bundle 111 to the center of the bundle in a direction substantially perpendicular to the hollow fiber membrane while being filtered by the hollow fiber membrane. , Filtrate outlet 1
It is taken out from 22. In the filter having such a structure, the hollow fiber membrane bundle is constantly compressed by the flow of the fluid to be treated, and the hollow fiber membrane is often cut near the potting material.

[0006]

One of the advantages of the hollow fiber membrane type fluid separation device is that the effective membrane area can be made larger than that of other shapes. However,
If the hollow fiber membranes are densely packed, the fluid flow will be non-uniform, and not all hollow fiber membranes will be used effectively. If a shape-retaining material that retains the shape of the bundle is used to make the filling state of the hollow fiber membranes uniform, not only the device becomes complicated, but also the filling amount of the hollow fiber membranes is reduced by the amount of the retaining material. In addition, depending on the shape of the holding material, even free vibration of the hollow fiber membrane is hindered, so that deposits accumulate on the surface of the hollow fiber membrane, which causes a drawback such as easy clogging. Further, as described above, the flow of the fluid to be treated may generate shearing force in the hollow fiber membrane near the potting material, and the hollow fiber membrane may be cut.

The problem to be solved by the present invention is to make the flow of the fluid uniform while maintaining the shape of the bundle itself, and to reduce the action of cutting the hollow fiber membrane, thereby making it possible to realize the above conventional hollow fibers. It is to remedy the drawbacks of membrane filters.

[0008]

In the present invention, the above-mentioned problem is a hollow fiber membrane type fluid separation device in which the open end of the hollow fiber membrane is converged and fixed together with a storage container at one location. The fiber membrane is folded back in a loop shape having a plurality of intersections, and the loop portion has a space communicating with one or more straight portions of the hollow fiber membrane bundle and has no shape-retaining material. This is solved by a hollow fiber membrane type cartridge filter characterized in that the fiber membrane bundle is housed in a housing container having a small fluid passage near the focusing and fixing portion and a large fluid passage near the loop portion. Further, such a hollow fiber membrane bundle is produced by winding a hollow fiber membrane produced by dry-wet spinning while twilling it with a biaxial cassette having one or more rod-shaped projections in the diameter direction.

[0009]

The hollow fiber membrane bundle is formed so that all the hollow fiber membranes have a plurality of intersections, so that the bundle itself retains its shape. Further, a hollow fiber membrane bundle having a space communicating with the linear portion of the hollow fiber membrane bundle at one or more locations in the loop portion,
Since it is stored in a storage container having a small fluid passage near the focusing and fixing portion and a large fluid passage near the loop portion,
The fluid to be treated is dispersed in the hollow fiber membrane from the large fluid passage near the loop portion through the above-mentioned space provided in the loop portion and flows along the fiber axis direction of the hollow fiber membrane. The shearing force on the fiber membrane is reduced, and the hollow fiber membrane is prevented from being cut at this portion. Also,
Since the hollow fiber membrane bundle is not fixed by the shape-retaining material, the hollow fiber membrane is prevented from shaking or vibrating which is naturally generated by the flow of fluid.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the embodiments shown in the drawings. FIG. 1 shows a winding step for producing a hollow fiber membrane bundle by the production method of the present invention, in which a continuous hollow fiber membrane 1 is traversed by a traverse 3 on a rotating biaxial cassette 2. The winding method is the same as the conventional method. However, the hollow fiber membrane winding portion 4
Another difference is that one or more rod-shaped projections 7 are provided substantially in the diameter direction of the cassette.

As shown in FIG. 2, when the winding portion 4 of the cassette 2 is formed into a semicircular shape having a diameter substantially equal to the diameter of the axial section of the linear portion 5 of the hollow fiber membrane bundle, the loop section has a cross section. The difference between the diameter and the diameter of the cross section of the linear portion becomes small, and the entire bundle is uniformly accommodated in the container for storing the hollow fiber membrane bundle, so that the flow of the fluid to be treated becomes more uniform.

FIG. 3 (a) shows an axial cross section of the bundle containing the cassette when wound by the cassette of FIG. 2, and FIG.
Shows a sectional view in a direction perpendicular to the axis of the bundle at the position of the arrow in FIG. The rod-shaped projection 7 gives the loop portion 6 a space communicating with the straight portion 5. As shown in FIG. 3 (b), by using the case having the shape shown in FIG. 2, the area of the case occupying each cross section of the loop part is small, and the difference between the diameter of the cross section of the loop part and the diameter of the cross section of the straight part is small. Becomes smaller.

Twill is provided by winding the hollow fiber membrane 1 around the cassette 2 and reciprocating the traverse 3 with a width substantially equal to the winding width. The number of reciprocations of the traverse 3 required for maintaining the shape of the hollow fiber membrane bundle by the hollow fiber membrane itself is about 1 to 5 per one rotation of the cassette 2. When this reciprocating cycle is shortened, the number of intersections of the hollow fiber membranes 1 increases, the outer diameter of the bundle is large (that is, the packing density of the hollow fiber membranes 1 is small), and the shape is retained more strongly. Within this range, not only the hollow fiber membrane itself retains the shape of the hollow fiber membrane bundle, but also the packing density of the hollow fiber membrane in the hollow fiber membrane bundle and the hollow fiber membrane bundle are stored in a cylindrical storage container. The filling state between the hollow fiber membrane bundle and the storage container at this time is also uniform, and the fluid flows uniformly over the entire hollow fiber membrane.

The outer diameter of the hollow fiber membrane used in the present invention is about 400 to 2000 μm. If it is less than 400 μm, the pressure loss of the filtrate flowing inside the hollow fiber membrane becomes large, which is not preferable. When it exceeds 2000 μm, the effective film area becomes small, which is not preferable.

The number of hollow fiber membranes wound around a cassette capable of exerting the effects of the present invention depends on the thickness of the hollow fiber membranes, but when the hollow fiber membranes have a thickness of 2000 μm, about 100 or more, 400
It is about 2000 or more in μm. If the thickness of the hollow fiber membrane bundle exceeds about 10 cm, it is possible to use a plurality of thin hollow fiber membrane bundles.

The hollow fiber membrane to be sent to the cassette is not particularly limited in the range of one set to 20 sets. When the number of hollow fiber membranes exceeds 20, the density of this set of hollow fiber membranes inevitably increases, and the packing density of the entire hollow fiber membrane bundle becomes excessively large. It is not preferable in the field of processing a fluid containing a relatively large amount of a substance that closes the gap. The length of the hollow fiber membrane bundle is not particularly limited, but is usually several cm to about 2 m.

The hollow fiber membrane which can be effectively carried out by the present invention is
It is a dry-wet spinning process, which is in a non-dried state, and more preferably the one in which the solvent remains and the coagulation is not completely completed. By dry-wet spinning, for example,
Ultrafiltration membranes and microfiltration membranes made of polyacrylonitrile, polymethylmethacrylate, polyvinylidene fluoride, cellulose acetate, nylon, polysulfone, polyethersulfone, etc. are manufactured, but they are all flexible in the undried state. , Without being loosened, it is rolled up by the cassette. When dried in this state, the state of the hollow fiber membrane bundle is fixed as it is. In addition, if the hollow fiber membrane in which the solvent remains and the coagulation is not completely completed is wound up and the coagulation is terminated in this state, even if the hollow fiber membrane bundle is removed from the cassette and dried, The state is maintained.

FIG. 4 shows the hollow fiber membrane 1 of the hollow fiber membrane type cartridge filter 10 of the present invention assembled by a known method using the hollow fiber membrane bundle manufactured as described above.
1 shows a cross section in the direction of the loop surface including the space 17 formed by the bar-shaped projections, and FIG. 5 shows a cross section in the direction perpendicular to the loop surface including the space 17 formed by the bar-shaped projections. The hollow fiber membrane is bundled and fixed by a potting material 12 at one end together with a cylindrical container 13 that houses the hollow fiber membrane bundle 11. The storage container 13 has a large fluid passage 14 near the loop portion 16 and a small fluid passage 1 near the potting portion.
5 are provided. The large fluid passage 14 may be the open bottom of the storage container 13 as shown,
It may be a hole provided in the side wall near the loop portion of the storage container 13. The passage cross-sectional area of the large fluid passage 14 is preferably about 50 times or more the passage cross-sectional area of the small fluid passage 15. In addition, the space 1 formed in the loop part
The fluid passage cross-sectional area of 7 is preferably about twice as large as the small fluid passage cross-sectional area or more.

FIG. 6 shows a state in which the hollow fiber membrane type cartridge filter 10 of the present invention is attached to the filter housing 20 and used. Most of the fluid to be treated supplied from the inlet 21 is hollow from the large fluid passage 14 of the hollow fiber membrane type cartridge filter 10 through the space 17 formed in the loop portion 16 and the gap between the loop portion 16 and the storage container 13. It is distributed in the fiber membrane bundle 11 and flows toward the potting portion while being filtered along the axial direction of the hollow fiber membrane. Therefore, unlike the conventional cartridge filter shown in FIG. 8, the hollow fiber membrane is not cut near the potting portion due to the compression of the hollow fiber membrane bundle by the fluid to be treated.

When the hollow fiber membrane type cartridge filter of the present invention is clogged, air is blown from the large fluid passage 14 and so-called air scrubbing is performed to remove the clogging substances accumulated on the surface of the hollow fiber membrane. Is also possible.

Next, the present invention will be described with reference to specific examples, but the present invention is not limited thereto.

(Example 1) Polysulfone (Teijin Amoco Engineering Plastics Co., Ltd., P-350)
0) 20 parts by weight (hereinafter the same), N-methyl-2-pyrrolidone 66 parts, propylene glycol 9 parts, average molecular weight 3
While maintaining a spinning dope containing 5 parts of 0,000 polyethylene glycol at 65 ° C, N-methyl-2-pyrrolidone 6 was added.
With the coagulation liquid inside the hollow fiber consisting of 0 part and 40 parts of propylene glycol, it was extruded into the air from the double tubular nozzle, penetrated into the water at 70 ° C. about 20 cm downward, and allowed to run for about 3 m. The two rod-shaped projections 7 made of round rods having a diameter of 8 mm are provided on the semi-circular winding portion 4 having a diameter of about 60 mm, and the bundle has a thickness of about 45 cm. 3,200 rolls were wound so as to be 6 cm. At this time, the traverse 3 is almost 2 per one rotation of the cassette.
A bundle was created by traversing the hollow fibers in a reciprocating manner. Also, water was sprinkled on the bundle during winding so that coagulation would proceed.

The bundle wound around the cassette was bound with two bands at the center, and the gap between them was cut to take out two bundles having a total length of about 25 cm. Place these bundles in a gutter, 30% by volume
The acetone aqueous solution and then warm water were sequentially showered to remove the residual solvent and polyethylene glycol, and then the band was covered with a wire to hang the bundle for drying.

This hollow fiber membrane does not allow particles having a size of 0.5 μm to pass through, and the inner and outer diameters are 500 μm and 800, respectively.
μm. In addition, a paper tape was wound around the linear portion and the loop portion of the hollow fiber membrane bundle, and the corresponding diameters of the respective portions were measured from the lengths, and as a result, 56 mm and 60 mm, respectively.
mm. The loop part is a rod-shaped protrusion with a diameter of about 8 m.
A space of m was formed.

Using this hollow fiber membrane bundle, the hollow fiber membrane type cartridge filter shown in FIGS. 4 and 5 was prepared. The storage container 13 has an inner diameter of 62 mm, an outer diameter of 70 mm, and a length of about 2
Using a 5 cm polysulfone cylinder, the potting material has a thickness of about 15 mm, and the effective length of the hollow fiber membrane is about 20 cm.
The hollow fiber membrane was fixed together with the cylinder by urethane resin by a known centrifugal casting method so that

The large fluid passage 14 is an open end of the cylindrical container, and four small holes having a diameter of 4 mm are provided on the side surface of the cylinder at a position about 2 mm below the potting portion as a small fluid passage 15. A header 18 having a filtrate outlet was connected to the open end side of the hollow fiber membrane.

This hollow fiber membrane type cartridge filter was mounted on the housing 20 shown in FIG. 6 to conduct a water filtration test. A pump having a discharge flow rate of 100 L (liter) per minute was connected to the housing, the pump was repeatedly started and stopped, and rapid water supply and rapid stop were repeated. Even when this operation was repeated 100 times, the hollow fiber membrane was not cut.

(Comparative Example 1) The same procedure as in Example 1 was carried out except that a hollow fiber membrane bundle was prepared using the cassette of FIG. 7, and a porous cylinder having a non-perforated bottom on the loop side was used as a storage container. When the cartridge filter 110 shown in FIG. 8 was prepared and a water filtration test was conducted in the same manner as in Example 1, the hollow fiber membrane was cut after rapid supply of water and rapid stop were repeated 100 times. was there.

Example 2 In place of water in Example 1, 100 ppm aqueous dispersion of colloidal silica having an average particle size of 0.5 μm was flowed at about 7 L / min. Filtration pressure is about 50 mmH
Gradually rising from g, and after filtering about 900 L, about 5
When it reached 00 mmHg, the filtration was stopped. Air vent 24
After opening, the air is sent from the drain outlet 23 for 10 minutes with the colloidal silica aqueous solution being filled, and after leaving it for 30 minutes, the drain outlet 23 is opened to drain the liquid in the housing. It was After plugging the drain outlet, filtration of the colloidal silica aqueous solution was started again. The filtration pressure gradually increased from about 200 mmHg, and about 500 L was filtered until it reached 500 mmHg. Similar results were obtained by repeating this operation 10 times.

[0030]

When the hollow fiber membrane type cartridge filter of the present invention is used, the hollow fiber membrane is difficult to cut even if the filtration speed is increased. The hollow fiber membrane itself retains the shape of the hollow fiber membrane bundle and the fluid passage. Since the structure is simple, there is nothing that hinders the shaking or vibration of the hollow fiber membrane that naturally occurs due to the flow of fluid, so it is difficult to clog,
It has the effect of long life.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing a state in which a hollow fiber membrane is wound up by the method of the present invention.

FIG. 2 is an explanatory view showing a more preferable state in which the hollow fiber membrane is wound by the method of the present invention.

FIG. 3 shows a loop portion of the hollow fiber membrane bundle wound with the cassette of FIG. 2, (a) is an axial sectional view of the bundle including the cassette,
(B) shows the sectional view on the AA line in the direction perpendicular to the axial direction of the bundle at the position of the arrow in (a).

FIG. 4 is a cross-sectional view of the hollow fiber membrane-type cartridge filter of the present invention assembled using the hollow fiber membrane bundle prepared by the method of the present invention, in a loop plane direction of the hollow fiber membrane bundle.

FIG. 5 is a sectional view of the hollow fiber membrane bundle in a direction perpendicular to the loop surface.

FIG. 6 is a schematic explanatory diagram when the hollow fiber membrane type cartridge filter of the present invention is attached to a filter housing for use.

FIG. 7 shows a state in which a hollow fiber membrane is wound around a cassette by a conventional method.

FIG. 8 is a schematic view showing a conventional hollow fiber membrane type cartridge filter including a conventional hollow fiber membrane bundle and a usage state thereof.

[Explanation of Codes] 1 hollow fiber membrane 2 cassette 3 traverse 4 winding section 5 linear portion of hollow fiber membrane bundle 6 loop portion of hollow fiber membrane bundle 7 rod-shaped protrusion 10 hollow fiber membrane type cartridge filter 11 hollow fiber membrane bundle 12 Potting material 13 Hollow fiber membrane storage container 14 Large fluid passage 15 Small fluid passage 17 Loop space 18 Header 20 Filter housing 21 Treated liquid inlet 22 Filtrate liquid outlet 23 Filter housing drain vent 24 Filter housing air vent

Claims (3)

[Claims] 1. A hollow fiber membrane type fluid separation device in which an open end of a hollow fiber membrane is focused and fixed together with a storage container at one location, and all hollow fiber membranes have loops each having a plurality of intersections. The hollow fiber membrane bundle, which has a shape in which the loop portion has a space communicating with one or more linear portions of the hollow fiber membrane bundle and has no shape-retaining material, is a small fluid near the focusing and fixing portion. A hollow fiber membrane type cartridge filter, which is housed in a housing container having a large fluid passage near the passage and the loop portion. 2. The hollow fiber membrane type cartridge filter according to claim 1, wherein there are two or more hollow fiber membrane bundles. 3. The hollow fiber membrane bundle is wound around a hollow fiber membrane produced by dry-wet spinning while twilling it with a biaxial cassette having one or more rod-shaped projections in the diameter direction, and the bundle has the same shape. The hollow fiber membrane type cartridge filter according to claim 1 or 2, which is held by itself.