JP3324900B2 - Hollow fiber membrane module - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a bundle of a large number of thin hollow fibers as a filtration membrane, and is a hollow fiber membrane module widely used for water purifiers and other medical and industrial uses. About. More specifically, the present invention relates to a hollow fiber membrane module in which a bundle of the hollow fiber membranes is loaded into a case and sealed at an end of the case while communicating the bundle of hollow fiber membranes with the outside of the case.

[0002]

2. Description of the Related Art As a conventional hollow fiber membrane module of this type, for example, there is one as shown in FIG. That is, the hollow fiber membrane module is composed of a bundle 100 of hollow fiber membranes 100A.
Is sealed in the case 101, and at the end of the case 101, the hollow fiber membrane bundle 100 is sealed while communicating with the outside of the case 101. A potting agent (sealing) for sealing the end of the case 101 Agent) 102 is case 101
Was just filled inside.

[0003]

However, the prior art in which the potting agent 102 merely fills the inside of the case 101 is susceptible to heat and pressure. In other words, when the working temperature such as the temperature of the stock solution to be filtered, the environmental temperature, or the pressure inside the case is high,
Due to the difference in the coefficient of thermal expansion, the difference in deformation, and the pressure between the plastic case 101, the potting agent 102, and many hollow fiber membranes 100A, the case 101 and the potting agent 10
2. There was a problem that the potting agent 102 and many of the hollow fiber membranes 100A peeled off somewhere, causing cracks and causing undiluted solution to leak from the end of the case 100 of the hollow fiber membrane module.

Further, in the hollow fiber membrane module described above, there is the following one in order to have strength against pressure inside and outside the case 101.

[0005] The hollow fiber membrane module shown in FIG. 14 has a tapered surface 103 having a diameter reduced toward an end to be sealed inside a case 101. Direction) (internal pressure). However, it has no effect on the pressure (external pressure) from the opposite direction (the direction of arrow H in the figure).

Some hollow fiber membrane modules shown in FIG. 15 are provided with projections 104 inside the potted end of the case 101 to improve the strength against internal and external pressures. However, since the projections 104 are provided by undercutting, in the case of a large hollow fiber membrane module, the strength cannot be maintained against internal and external pressures, so that the module is applied to only small ones. Can be

As described above, the conventional hollow fiber membrane module does not have sufficient strength against the internal and external pressure of the case 101.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and it is an object of the present invention to improve a sealing portion for sealing a bundle of hollow fiber membranes at the end of the case while communicating the bundle of hollow fiber membranes with the outside of the case. Thereby, the heat resistance of the hollow fiber membrane module is improved, the pressure resistance is improved, and the quality and reliability are improved.

[0009]

In order to achieve the above object, according to the present invention, a bundle of hollow fiber membranes is loaded into a case, and at the end of the case, the bundle of hollow fiber membranes is attached to the case. In a hollow fiber membrane module which is sealed while communicating with the outside, an inner surface of the case, an end surface of the case by a potting agent for sealing an end of the case.
And the outer surface of the case is continuously covered .

[0010] It is also possible to provide a through hole that penetrates the casing inside and outside the casing end. Furthermore, the case
Is preferably a stepped end.

[0011]

In the hollow fiber membrane module having the above structure, the adhesion between the case and the potting agent is continuous on the inside of the case and also on the case end surface and the case outer surface. The operating temperature, the environmental temperature, or the pressure inside the case increases, causing expansion and thermal deformation due to temperature and internal pressure. If the inside of the case is peeled off somewhere between the inner surface of the case, the potting agent, or the hollow fiber membrane, Even if a crack occurs, the probability of the crack leading to peeling of the end face of the case and peeling of the outer surface of the case is reduced. Therefore, in the case of the present invention, as compared with the case where the potting agent is injected only into the inside of the case end, the case of the case due to peeling or cracking of the potting agent in a state where the temperature is high and a case where the internal pressure of the case is high is increased. The probability of undiluted solution leaking from the end is reliably reduced.

Further, by providing a through hole penetrating the inside and outside of the case at the end of the case, the bonding between the case and the potting agent is performed as described above through the through hole. Since it is filled and the inside and outside of the case will be integrally sealed,
The strength is increased both for the pressure from the inside of the case and for the pressure from the outside of the case. Therefore,
The pressure resistance against external pressure is improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS.

Reference numeral 1 denotes a case of a hollow fiber membrane module, which is generally made of plastic. The plastic case 1 is cylindrical and has an open end.

Reference numeral 2 denotes a bundle of hollow fiber membranes 2A loaded inside the case 1. As shown in FIG. 5, the hollow fiber membrane 2A is, for example, a thread-shaped tube each having an outer diameter of about 1 mm or thinner, and a portion of the tube serving as a filtration membrane serves as a filtration membrane. This allows a fluid such as a liquid to penetrate from outside to inside (solid arrow in the figure) or from inside to outside (dotted arrow in the figure) to remove impurities and concentrate necessary components of the fluid. it can. Since a single hollow fiber membrane 2A has a small filtration area and therefore a small filtration capacity, a predetermined filtration capacity can be obtained by collecting a large number of these.

FIGS. 6 and 7 show an example of a structure in which a bundle of hollow fiber membranes 2A is used to form a filtration membrane module, that is, a hollow fiber membrane module.

In FIG. 6, the hollow fiber membrane bundle 2 is loaded into a cylindrical case 1 as it is, and both ends of the case 1 are connected to the outside of the hollow fiber membrane 2A one by one. While communicating, the space between the outside of the hollow fiber membrane 2A and the inside of the case 1 is completely closed (this is referred to as sealing).
For example, an inlet 4 and an outlet 8 are provided in the cylindrical portion of the case 1, and when the stock solution to be filtered is pressurized and flows through the case 1 as shown by arrows A → B in the figure, the stock solution flows from the outside of the hollow fiber membrane 2A. The liquid permeates inward and the filtered liquid flows out from both ends C and D of the case 1. The flow of the stock solution and the filtered solution is a cross-flow type.

In FIG. 7, the hollow fiber membrane bundle 2 is bent into a U-shape, and only one end E of the case 1 is passed through the hollow fiber membrane bundle 2.
Seal. Then, for example, a pressurized stock solution is poured from the other end F that is left open. Then, the filtered liquid flows out from the sealed end E through the hollow fiber membrane bundle 2 communicating with the outside of the case 1. The flow of the undiluted solution and the filtered liquid is of a total filtration type.

The subject of the present invention is a hollow fiber membrane 2A one by one.
The inside of the cylinder described above is a method of sealing that completely closes the space between the outside of the hollow fiber membrane 2A and the inside of the case 1 while communicating with the outside of the case 1, and FIG. 6 and FIG. This applies to both the cross-flow type and the total filtration type shown.

The structure of the sealing portion of the hollow fiber membrane module according to one embodiment of the present invention will be described below, while explaining the method of sealing the end of the case 1 according to one embodiment of the present invention. .

As shown in FIG. 1, the outside of the end of the case 1 on the side to be sealed is a stepped end 3 having a predetermined length and a smaller diameter than other places.

Next, before the hollow fiber membrane bundle 2 is loaded into the case 1, the ends of the hollow fiber membrane 2A are aligned, and only the short length of the end of the hollow fiber membrane bundle 2 ( 2a is immersed in, for example, an adhesive solution, or is immersed in a solution for dissolving the hollow fiber membrane 2A for a short time so that only the length of the end a is adhered or welded to form a hole in the hollow fiber membrane 2A. Is closed.

Next, the hollow fiber membrane bundle 2 is loaded into the case 1 as shown in FIG. In this case, a fixed length of the end of the hollow fiber membrane bundle 2 is taken out of the case 1. Its length is longer than in FIG. Then, the potting adapter 5 is put over the portion beyond the stepped end 3 of the case 1 and sealed. Since the potting adapter 5 has an inlet 6, the potting agent 7 is injected into the end of the case 1 and solidified through the inlet. The potting agent 7 covers not only between the inside of the case 1 and the hollow fiber membrane bundle 2 and between the hollow fiber membranes 2A, but also the end face of the case 1 and the stepped end 3 on the outside. However, since the hole of the hollow fiber membrane 2A is closed, the potting agent 7 cannot enter the hole.

After the potting agent 7 solidifies, the potting adapter 5 is removed, and the hollow fiber membrane bundle 2 protruding from the case 1 is cut (see FIG. 4).

The cut position is a position where the cut is larger than the length a in which the hole of the hollow fiber membrane 2A is closed, but is only b outside from the end of the case 1.

As a result, each of the hollow fiber membranes 2A communicates with the outside of the case 1, and the sealing state (sealed portion) at the end of the case 1 is such that the potting agent 7 is Between the inside of the case 1 and the hollow fiber membrane bundle 2, as well as the end face of the case 1 and the stepped end 3 on the outside, the shape is connected and covered.

The adhesion between the case 1 and the potting agent 7
In the sealed portion of the hollow fiber membrane module of FIG. 4, since the end portion of the case 1 and the outer surface of the case 1 are continuous in addition to the sealed state of the hollow fiber membrane module of FIG. The working temperature such as the temperature, the environmental temperature, or the pressure inside the case 1 increases, causing expansion and thermal deformation due to the temperature and the internal pressure. As a result, inside the case 1, the inner surface of the case 1, the potting agent 7, Hollow fiber membrane 2A
If the peeling or cracking occurs somewhere in between, the probability of the peeling or cracking of the end face of the case 1 and the peeling of the outer surface of the case 1 decreases. Accordingly, the state of FIG. 4 is different from the state of FIG.
, The probability of undiluted solution leaking from the end of the liquid is surely reduced.

FIG. 8 shows a hollow fiber membrane module according to another embodiment of the present invention. In this embodiment, as shown in FIG. 8, in the first embodiment, a plurality of through holes 31 penetrating the inside and outside of the case 1 are provided in the stepped end portion 3 of the case 1 in the circumferential direction. The potting agent 7 is connected not only between the hollow fiber membranes 2A, between the inside of the case 1 and the hollow fiber membrane bundle 2 but also to the outside of the case 1, that is, the end face of the case 1 and the stepped end 3 on the outside. And the inside and outside of the case 1 are integrally sealed.

As described above, the potting agent 7 is
Is filled to seal the inside and outside of the case 1 integrally, so that the flow from the inside of the case 1 (direction I in the drawing)
And the pressure against the flow from the outside of the case 1 (in the direction J in the drawing). Therefore, it is possible to improve the pressure resistance against the internal and external pressures.

Although the improvement in the pressure resistance is small, the number of the through holes 31 may be one.

Hereinafter, a method of sealing the end of the case 1 according to another embodiment of the present invention will be described, while the sealing portion of the hollow fiber membrane module according to the above another embodiment of the present invention will be described. Will be described with reference to FIGS. 9 to 12 and FIG.

As shown in FIG. 9, the outside of the end of the case 1 on the side to be sealed is a stepped end 3 having a smaller diameter than the other end by a predetermined length, and the stepped end 3 is provided. The part 3 is provided with a plurality of through holes 31 penetrating the inside and outside of the case 1 in the circumferential direction.

Next, before the hollow fiber membrane bundle 2 is loaded into the case 1, the ends of the hollow fiber membranes 2A are aligned, and then the short ends of the hollow fiber membrane bundles 2 are added ( 2a is immersed in, for example, an adhesive solution, or is immersed in a solution for dissolving the hollow fiber membrane 2A for a short time so that only the length of the end a is adhered or welded to form a hole in the hollow fiber membrane 2A. Is closed.

Next, as shown in FIG.
Into Case 1. In this case, a fixed length of the end of the hollow fiber membrane bundle 2 is taken out of the case 1. Its length is longer than in FIG. Then, the potting adapter 5 is put over the portion beyond the stepped end 3 of the case 1 and sealed. Since the potting adapter 5 has an inlet 6, through which the potting agent 7 is injected into the end of the case 1 and solidified. The potting agent 7 is provided not only between the inside of the case 1 and the hollow fiber membrane bundle 2 through the through hole 31 but also between the hollow fiber membranes 2A.
It covers the outside of the case 1, that is, the end face of the case 1 and the stepped end 3 on the outside. However, since the hole of the hollow fiber membrane 2A is closed, the potting agent 7 cannot enter the hole.

After the potting agent 7 solidifies, the potting adapter 5 is removed, and the hollow fiber membrane bundle 2 protruding from the case 1 is cut (see FIG. 11).

Although the cut position is cut out larger than the length a in which the hole of the hollow fiber membrane 2A is closed, a position outside the end of the case 1 (dotted line in the figure).
It is.

As a result, as shown in FIG.
A is in communication with the outside of the case 1, and the sealed state (sealed portion) at the end of the case 1 is a potting agent 7.
Are located between the hollow fiber membranes 2A through the through holes 31 and between the inside of the case 1 and the hollow fiber membrane bundle 2 as well as the case 1
, That is, the end face of the case 1 and the stepped end 3 on the outside.

[0038]

The present invention has the above-described structure and operation. A bundle of hollow fiber membranes is loaded in a case, and at the end of the case, the bundle of hollow fiber membranes is communicated with the outside of the case. In the sealed hollow fiber membrane module, a potting agent for sealing the end of the case is injected into the inside of the case, and also covers the case end surface and the case outer surface continuously inside the case. As the working temperature such as the temperature of the undiluted solution, the environmental temperature, or the pressure inside the case increases, expansion and thermal deformation occur due to temperature and pressure. Even if peeling or cracking occurs somewhere between the potting agent and the hollow fiber membrane, the probability of the peeling or cracking of the case end face and the case outer face being reduced. Therefore, compared to the case where the potting agent is injected only inside the case end, the probability of the undiluted solution leaking from the sealed end of the case due to the peeling or cracking of the potting agent at a high temperature, It will surely be smaller.

Further, by providing a through hole penetrating the inside and outside of the case at the end of the case, the adhesion between the case and the potting agent is performed through the through hole as described above. Since it will be filled and the inside and outside of the case will be integrally sealed
The strength is increased with respect to the pressure from the inside of the case and also from the pressure from the outside of the case, and the pressure resistance against the internal and external pressures can be improved.

As described above, the heat resistance and the pressure resistance of the hollow fiber membrane module were improved, and the quality and reliability were improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a case end of a hollow fiber membrane module according to one embodiment of the present invention.

FIG. 2 is a schematic side view of a bundle of hollow fiber membranes before being loaded into the case of FIG.

FIG. 3 is a cross-sectional view showing a state where a potting adapter is put on an end of a case after loading a bundle of hollow fiber membranes.

FIG. 4 is a sectional view of a sealed end of a hollow fiber membrane module according to one embodiment of the present invention.

FIG. 5 is a partial view of a hollow fiber membrane.

FIG. 6 is a sectional view of a structural example of a hollow fiber membrane module.

FIG. 7 is a cross-sectional view of another example of the structure of the hollow fiber membrane module.

FIG. 8 is a sectional view of a sealed end of a hollow fiber membrane module according to another embodiment of the present invention.

FIG. 9 is a half sectional view of a case end of a hollow fiber membrane module according to another embodiment of the present invention.

FIG. 10 is a half sectional view showing a state in which a potting adapter is put on a case end according to another embodiment of the present invention after a bundle of hollow fiber membranes is loaded.

FIG. 11 is a half sectional view showing a cutting position after a potting step is completed.

FIG. 12 is a half cross-sectional view of a case end after cutting a sealing portion.

FIG. 13 is a cross-sectional view of a sealed end of a conventional hollow fiber membrane module.

FIG. 14 is a sectional view of another conventional hollow fiber membrane module.

FIG. 15 is a sectional view of another conventional hollow fiber membrane module.

[Explanation of symbols]

 1 Case 2 Hollow Fiber Membrane Bundle 2A Hollow Fiber Membrane 3 Stepped End 31 Through Hole 4 Inlet 5 Potting Adapter 6 Inlet 7 Potting Agent 8 Outlet

Claims (3)

(57) [Claims] 1. A hollow fiber membrane module in which a bundle of hollow fiber membranes is loaded into a case and sealed at the end of the case while communicating the bundle of hollow fiber membranes with the outside of the case. potting agents for sealing parts
The inner surface of the case, the end surface of the case, and the case
A hollow fiber membrane module , wherein the outer surface of the base is continuously covered . 2. The hollow fiber membrane module according to claim 1, wherein a through hole penetrating through the inside and outside of the case is provided at the end of the case. 3. An end of the case is a stepped end.
The hollow fiber membrane module according to claim 1 or 2, wherein
Wool.