JPH10156149A - Hollow-fiber membrane module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the deformation of a layered air vent during filtration in a hollow-fiber membrane module formed by packing many hollow-fiber membranes with a sheet-shaped air vent means wound on them in a cylindrical case by providing a holding means to position the air vent means close to the inner periphery of the case. SOLUTION: A hollow-fiber membrane module 1 is formed by packing the fiber bundle 3 of a hollow-fiber membrane 3a in a cylindrical case 2, and a potting part 4 is provided to seal a gap between the end 3b of the bundle 3 and the inner periphery of one end 2a of the case 2. Meanwhile, a layered air vent 5 is previously wound on the periphery of the bundle 3, then many communicating holes 10 are formed by the potting, hence the air staying inside is discharged along with the membrane-permeated fluid, and a decrease in the membrane permeability is prevented. Further, a cap member 6 obtained by providing plural projecting members 6c to the periphery of a bottom plate 6a is inserted into an opening on the opposite side of the potting part 4 as a holding part to be positioned between the bundle 3 and the inner periphery of the case 2.

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 module having an air bleeding means inside, and a technique for stabilizing the behavior of the air bleeding means at the time of filtration to protect the hollow fiber membrane and to secure a permeation flow rate. About.

[0002]

2. Description of the Related Art Conventionally, for example, in a filtration device used for filtering tap water, tap water to be filtered is transmitted through the membrane surface of a hollow fiber membrane using a hollow fiber membrane module. Some perform filtration.

FIG. 5 (a) is an explanatory view of a cross-sectional configuration of a hollow fiber membrane module 101 loaded inside such a filtration device. The hollow fiber membrane module 101 is a cylindrical case 1
02, a hollow fiber membrane yarn bundle 103 bent in a U-shape
While maintaining the openings at the respective end faces of the hollow fiber membrane 103a, the end 103b of the yarn bundle 103 of the hollow fiber membrane and the case 10
2 is provided with a potting portion 104 (a portion indicated by a broken line) in which a gap between the one end portion 102a and the inner peripheral portion is sealed with a urethane-based or epoxy-based adhesive or the like.

At the time of use, the opening 1 of the case 102 is used.
Fluid to be filtered (for example, tap water) flowing from the hollow fiber membrane 02b from the membrane surface of the hollow fiber membrane 103a to the inner tube portion, and appears on the end surface 104a of the potting portion 104.
The membrane-permeated fluid flows out from the end face a.

[0005] In such a state of use, air bubbles such as air contained in the fluid to be filtered may cause the hollow fiber membrane 103a to become wet once the fluid to be filtered is passed through, and the hollow fiber membrane in the wet state may be wetted. Since the hollow fiber membrane module 101a has a property that it hardly penetrates the membrane surface of the hollow fiber membrane module 101a.
There is a problem in that it stays inside and the permeation flow rate decreases.

[0006] To solve this problem,
Since air remaining in the hollow fiber membrane module 101 may be discharged, the yarn bundle 103 of the hollow fiber membrane as shown in FIG.
A layered air vent 105 is previously wound around the outer periphery of the case 102 (only a part of the air vent 105 is broken in FIG. 5A), and then the inner peripheral surface of the case 102 and the yarn bundle 1 of the hollow fiber membrane are formed.
03 to form a large number of air communication holes 110 between the outer periphery,
The air staying inside flows out simultaneously with the membrane permeable fluid,
It has been practiced to prevent a decrease in the membrane permeation flow rate.

FIG. 5B is an enlarged view of a portion D1 in FIG. 5A. The structure of the layered air vent 105 will be described with reference to FIG. The layered air vent 105 has a substantially sheet-like external shape, and the nonwoven fiber 107 is sandwiched between two water-permeable sheets 106a and 106b that can be thermally welded with two air-permeable thin polypropylenes or polyethylenes. It is. Due to the presence of the non-woven fibers 107, a tunnel state is formed between the sheets 106a and 106b, and a large number of air communication holes 11 parallel to the yarn bundle 103 of the hollow fiber membrane.
0 is formed.

After the non-woven fibers 107 are sandwiched between the two sheets 106a and 106b, the non-woven fibers 107 are joined by heat compression or ultrasonic bonding, so that the joints 105a and the air communication holes 110 are formed alternately. Is done. The joining portion 105a
Although the eyes of the sheets 106a and 106b are crushed and the air permeability is lost, the air permeability is maintained in other portions.

FIG. 6 is a diagram schematically showing an actual use state of the hollow fiber membrane module 101.
The hollow fiber membrane module 101 is disposed inside 20. The water purifier 120 includes a lid member 121 and a housing 122.
The fluid to be filtered (tap water) is taken into the container made of the water from the inlet port 123, flows into the hollow fiber membrane module 101 along the arrow, and the filtered membrane permeated fluid flows out from the outlet port 124. Things.

The hollow fiber membrane module 101 has an outlet 12
The hollow fiber membrane 103 which is fitted into the cap 125 having the
The membrane-permeable fluid flowing out from the end face of “a” is guided to the outlet 124. Then, the air staying inside the hollow fiber membrane module 101 passes through the air communication hole 110 and is guided to the outlet 124 together with the membrane permeable fluid, and is discharged.

[0011]

However, when a pressure fluctuation or an increase in the pressure of the fluid to be filtered occurs, the laminar air vent disposed along the inside of the case 102 of the hollow fiber membrane module 101 as shown in FIG. 105 moves from its original position and causes a contact phenomenon (rubbing state) involving relative movement with the yarn bundle 103 of the hollow fiber membrane or the yarn bundle 103 of the hollow fiber membrane
And the hollow fiber membrane 103a may be damaged and damaged, or the permeation flow rate may be reduced.

In order to solve this problem, a measure is taken to provide the layered air vent 105 from the end face 104a by about half the length in the axial direction, or to provide a plurality of bundles of hollow fiber membranes and In order to secure the permeation flow rate, measures were taken to arrange a layered air vent in the air.

[0013] However, such measures have other problems such as a decrease in the amount of air bleeding due to a decrease in the amount of air bleeding, and the necessity of a protective sheet such as a nonwoven fabric because the end surface of the air bleeding hits the hollow fiber membrane. Was.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to suppress the deformation of the layered air vent during filtration in a hollow fiber membrane module having a layered air vent. Another object of the present invention is to maintain the membrane permeation flow rate of the hollow fiber membrane module.

[0015]

In order to achieve the above-mentioned object, according to the present invention, a plurality of hollow fiber membranes having a sheet-shaped air vent means wound therearound are loaded in a cylindrical case. A hollow fiber membrane module comprising a hollow fiber membrane located at at least one end of the case and a sealing portion for sealing a gap between the air vent means and the inner periphery of the case; A hollow fiber membrane module comprising a holding means positioned near a portion.

Therefore, since the air releasing means is held in the vicinity of the inner peripheral part of the case by the holding means, it is possible to separate from the inner peripheral part of the case and to strongly contact or press the yarn bundle of the hollow fiber membrane. Is prevented.

Further, the holding means is provided on a cap member attached to the other end of the case, and has a holding portion projecting so as to be located between the hollow fiber membrane and the air venting means. It is also preferable that the annular member is located between the yarn membrane and the air release means and fitted and fixed to the inner peripheral portion of the case.

The holding portion or the annular member holds the air bleeding means and suppresses the deformation in the diameter reducing direction.

It is also preferable that the holding means is a joining means for fixing the air releasing means by joining the air removing means to an inner peripheral portion of the case.

By this joining means, the air venting means is joined to the inner peripheral portion of the case to suppress deformation. As a joining method of the joining means, various methods such as bonding with an adhesive, ultrasonic bonding, and heat compression can be adopted.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the illustrated embodiment.

(Embodiment 1) FIG. 1 shows a hollow fiber membrane module according to a first embodiment of the present invention. The hollow fiber membrane module 1 is mounted inside a water purifier or the like that removes fine foreign substances and the like as dirt components contained in water (tap water or water stored in a water tank) as a fluid to be filtered. , Which is used when filtering inflowing water.

Here, the present invention relates to a hollow fiber membrane module, and the configuration of the water purifier and the loaded state of the hollow fiber membrane module 1 are the same as those in FIG. I do.

The hollow fiber membrane module 1 is loaded with a bundle of hollow fiber membranes 3 bent in a U-shape into a cylindrical case 2 formed of a plastic material or the like, and the end faces of the hollow fiber membranes 3a. In which the gap between the end portion 3b of the yarn bundle 3 of the hollow fiber membrane and the inner peripheral portion of one end portion 2a of the case 2 is sealed with an adhesive such as urethane or epoxy while maintaining the opening of A portion 4 (broken line portion) is provided.

The bundle 3 of hollow fiber membranes is preliminarily wrapped with a sheet-like layered air vent 5 around the outer periphery in order to discharge the air collected inside the hollow fiber membrane module 1, and then potting is performed. A number of air communication holes 10 are formed between the inner peripheral surface of the hollow fiber membrane 2 and the outer periphery of the yarn bundle 3 of the hollow fiber membrane, and the air staying inside is discharged at the same time as the membrane permeating fluid to reduce the permeation flow rate. Preventing.

The layered air vent 5 has the same configuration as that described with reference to FIG. 5B. The non-woven fiber is sandwiched between two air-permeable thin sheets, and is parallel to the yarn bundle 3 of the hollow fiber membrane. A large number of tunnel-shaped communication holes 10 are formed.

Reference numeral 6 denotes a cap member which is attached to the opening of the case 2 opposite to the potting portion 4. The cap member 6 has a bottom plate portion 6 fitted to the inner peripheral shape of the case 2.
a, and the bottom plate 6 a is fitted and fixed to the case 2. 6b is an opening through which the fluid to be filtered flows into the hollow fiber membrane module.

Reference numeral 6c denotes a projecting member as a holding portion located between the yarn bundle 3 of the hollow fiber membrane and the inner peripheral portion of the case 2, and is provided on the outer periphery of the bottom plate portion 6a as shown in FIG. A plurality of them are provided slightly inside along. Therefore, this projecting member 6
By attaching the cap member 6 so as to sandwich the layered air vent 5 between the inner peripheral portion of the case 2 and the case 2, the layered air vent 5
Is located in the vicinity of the inner peripheral portion of the case 2, and even if pressure fluctuation or pressure rise of the fluid to be filtered occurs, the hollow fiber membrane 5 is prevented from being rubbed or pressed against the yarn bundle 3 by the layered air vent 5. It becomes possible.

Since the inner peripheral side of the projecting member 6c is in contact with the yarn bundle 3 of the hollow fiber membrane, it is possible to prevent the yarn bundle 3 of the hollow fiber membrane from being damaged by forming it into an appropriate round shape.

FIG. 2 shows a modification of the first embodiment. In FIG. 2A, a cylindrical holding portion 16c is joined to a bottom plate 16a of a cap member 16. This holding part 1
6c is provided with a plurality of windows 16d.
Air staying inside the hollow fiber membrane module through d can come into contact with the layered air vent 5. The cylindrical holding portion 16c also holds the layered air vent 5 between the projecting member 16c and the inner peripheral portion of the case 2 similarly to the holding portion 6c of FIG.

FIG. 2B shows a projecting member 26c corresponding to the projecting member 6c arranged annularly in FIG. 1 and an annular connecting portion 26d connecting the projecting member 26c annularly in the axial direction of the projecting member 26c. Is provided at a predetermined position. With this configuration, the bending rigidity of the protruding member 26c is increased, and the deformation of the laminar air vent 5 in the diameter-reducing direction can be prevented even when a high-pressure filtration target fluid is supplied.

(Embodiment 2) FIG. 3 shows a hollow fiber membrane module according to a second embodiment of the present invention. In the hollow fiber membrane module 31 of FIG. 3, the same components as those of the hollow fiber membrane module 1 of FIG. 1 are denoted by the same reference numerals.

The hollow fiber membrane module 31 is located between the yarn bundle 3 of the hollow fiber membrane and the layered air vent 5 as a holding means for the layered air vent 5, and is provided on the inner periphery of the case 2.
And a fixing ring 32 as an annular member that is fitted and fixed so as to sandwich the fixing ring 32.

The fixing ring 32 is shown in FIGS.
The form as shown in (d) can be adopted as an example. FIG. 3B shows a closed fixing ring 32, and FIG.
(C) is a substantially C-shaped fixing ring 33 with a part opened, FIG.
(D) is a fixing ring 34 provided with a plurality of protrusions 34a on the outer periphery in the radial direction.

As a feature of each fixing ring, the fixing ring 32 has a high rigidity in the diameter reducing direction, and has a laminar air release 5.
Can be securely fixed. The fixing ring 33 can be easily mounted. The fixing ring 34 can hold the communication hole 10 of the layered air vent 5 without being crushed by the protruding portion 34a.

A plurality of the fixing rings can be provided in the axial direction of the hollow fiber membrane module 31.
A concave groove may be provided in the inner peripheral portion of the case 2 so that the fixing ring is not moved, and the fixing ring may be fitted therein.

(Embodiment 3) FIG. 4 shows a hollow fiber membrane module according to a third embodiment of the present invention. In the hollow fiber membrane module 41 of FIG. 4, the same components as those of the hollow fiber membrane module 1 of FIG.

In the hollow fiber membrane module 41 of the third embodiment, in order to prevent deformation of the layered air vent 5,
At a position distant from the potting portion 4, a heat-compression bonding is performed in a spot manner by an arm 42 of a thermocompression bonding device as a bonding means, and a plurality of bonding portions 43 are formed in a circumferential direction. The cap member may be fitted after thermocompression bonding.

When the deformation of the layered air vent 5 is prevented by such a method, a joining step such as a heat-pressing step is required, but a new member such as a cap member with a holding member or a fixing ring is not required. It can be immediately applied to hollow fiber membrane modules of different sizes and designs.

[0040]

EXAMPLE In order to confirm the effects of the present invention, a hollow fiber membrane module 1 (hereinafter referred to as an example) having a cap member 26 shown in FIG.
The change in the flow rate with the hollow fiber membrane module 101 (comparative example) shown in FIG. 5 described in the related art is compared with the pressure differential pressure (0.2, 0.5, 1.0) before and after filtration of the fluid to be filtered.
(Kgf / cm ² )).

Each test sample has a case inner diameter of 30 mm, an effective length in the case of 60 mm, and a filling factor at the end face of the hollow fiber membrane of 45%.

In the embodiment, the differential pressures of 0.2, 0.5,
For 1.6 (kgf / cm ² ), 1.6, 3.9, and 7.
A membrane permeable fluid of 0 (l / min) was obtained. In the comparative example, 1.5, 3.
A membrane permeation fluid of 4,5.8 (l / min) was obtained.

This result shows that the embodiment can obtain a larger membrane permeation flow rate at all pressure differential pressures.
As the pressure differential pressure increased, the difference in the membrane permeation flow rate from the comparative example increased, and the effect of the present invention could be confirmed.

[0044]

According to the hollow fiber membrane module having the above construction and operation, the air releasing means is held near the inner peripheral part of the case by the holding means, so that the hollow fiber membrane is separated from the inner peripheral part of the case. It is possible to prevent strong contact or pressure with the yarn bundle, suppress deformation of the air venting means at the time of filtration, and maintain the membrane permeation flow rate of the hollow fiber membrane module.

The holding means suppresses the deformation of the air venting means in the diameter reducing direction and prevents the yarn bundle of the hollow fiber membrane from being pressed.

The air releasing means is joined to the inner peripheral portion of the case by the joining means and is not deformed, so that compression of the yarn bundle of the hollow fiber membrane is prevented.

[Brief description of the drawings]

FIG. 1 is a diagram of a hollow fiber membrane module according to a first embodiment of the present invention.

FIG. 2 is a view of a modification of the cap member according to the first embodiment of the present invention.

FIG. 3 is a diagram of a hollow fiber membrane module according to a second embodiment of the present invention.

FIG. 4 is a diagram of a hollow fiber membrane module according to a third embodiment of the present invention.

FIG. 5 is a diagram of a conventional hollow fiber membrane module.

FIG. 6 is a schematic view of a water purifier using a hollow fiber membrane module.

FIG. 7 is a diagram illustrating a state in which the yarn bundle of the hollow fiber membrane is pressed during filtration of the hollow fiber membrane module.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hollow fiber membrane module 2 Case 2a One end 3 Thread bundle of hollow fiber membrane 3a Hollow fiber membrane 3b End 4 Potting part 5 Layered air vent (air vent means) 6 Cap member 6a Bottom plate part 6b Opening 6c Projecting member (holding part) ) 10 Communication hole

Claims (4)

[Claims] 1. A plurality of hollow fiber membranes, each of which has a sheet-shaped air release means wound therearound, are loaded into a cylindrical case, and the hollow fiber membrane and the air release means are located at at least one end of the case. A hollow fiber membrane module provided with a sealing portion for sealing a gap between the case and an inner peripheral portion of the case, wherein the hollow fiber membrane module comprises a holding device for positioning the air venting device near the inner peripheral portion of the case. . 2. The method according to claim 1, wherein the holding means is provided on a cap member attached to the other end of the case, and includes a holding portion projecting so as to be located between the hollow fiber membrane and the air venting means. The hollow fiber membrane module according to claim 1. 3. The hollow fiber according to claim 1, wherein the holding means is an annular member which is located between the hollow fiber membrane and the air venting means and is fitted and fixed to an inner peripheral portion of the case. Membrane module. 4. The hollow fiber membrane module according to claim 1, wherein the holding means is a joining means for fixing the air release means by joining it to an inner peripheral portion of the case.