JPH07236819A - Air bubble disperser - Google Patents

Abstract

PURPOSE:To enhance the washing effect of a hollow yarn membrane while achieving the protection of the hollow yarn membrane and facilitating the production of thereof. CONSTITUTION:This air bubble disperser is equipped with a rotary member 21 supported within a case having a liquid received therein in a freely rotatable manner, an air bubble supply part 12 supplying air bubbles A into the liquid from under side of the rotary member 21 and a rotary member driving means 20 converting the buoyancy of the air bubbles A to the rotatory power of the rotary member 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bubble disperser for supplying bubbles into a liquid in a case of a hollow fiber membrane module in order to remove deposits accumulated on the surface of the hollow fiber membrane.

[0002]

2. Description of the Related Art Conventionally, there is a hollow fiber membrane module as shown in FIG. That is, in this hollow fiber membrane module 100, one end of each hollow fiber membrane 101 is kept open at both end portions of a bundle of a large number of hollow fiber membranes 101 while the hollow fiber membranes 101 are bonded and fixed to each other. Therefore, the hollow fiber membrane bundle 103, in which the gap between the hollow fiber membranes 101 is sealed and fixed (potted) by the sealing material 102, is used for each hollow fiber membrane 1
The end of No. 01 is suspended in the case 105 via the suspending member 106 at the potting portion 104 having the open end surface 111 of the hollow fiber membrane which is opened and potted.

The case 105 has a bubble supply port 107 as a bubble supply part for supplying the bubble A into the case 105 at the bottom, a permeate outlet 108 at the top, and an axially inner side of the potting part 104. On the side of the case 105
A stock solution supply port 109 for supplying the stock solution is provided therein, and a bubble outlet 110 for letting the bubbles A escape from the case 105 is provided on a side surface facing the stock solution supply port 109 in cross section.

The hollow fiber membrane module 100 described above is used.
Is used in the field of sewage treatment and the like, and is used for filtration and the like, which contains a relatively large amount of pollutants. Filtration is performed as follows. That is, from the undiluted solution supply port 109 to the case 105
An undiluted solution is supplied into the hollow fiber membrane 101, and the undiluted solution is filtered from the surface of each hollow fiber membrane 101 by passing through the inside to obtain a permeate. It is an external pressure type that is discharged.

In such a filtration operation, each time the filtration pressure rises, air bubbles A are supplied into the liquid through the air bubble supply port 107, and the air bubbles A are applied to the hollow fiber membrane 101 to cause the hollow fibers to flow. Bubble cleaning is performed to remove contaminants deposited on the surface of the film 101.

[0006]

However, in the case of the above-mentioned conventional technique, when the bubble A hits the lower potting portion 112, the bubble A shifts upward, and only one side of the hollow fiber membrane 101 can be washed. . Further, when a large amount of bubbles A are supplied to wash the whole, a portion where the bubbles are concentrated and hit is formed, and the hollow fiber membrane 101 in that portion is damaged.

Therefore, in order to supply the air bubbles A to the hollow fiber membrane bundle 103 all around, a plurality of holes 114 opened downward in a ring-shaped tube 113 as shown in FIG.
There is a hollow fiber membrane module 100 in which a structure in which a tube 115 communicating with the bubble supply port 107 is connected to the tube 113 is provided on the bottom of the case 105.

However, although the bubble A is supplied all around, the bubble A rises directly, so that the bubble A may hit the lower potting portion 112 and the bubble A may be offset. As a result, the potting portion 112 at the bottom of the hollow fiber membrane bundle 103 tilts to the opposite side to the side where the air bubbles A are offset, and once tilted, it cannot be restored, so the air bubbles A remain offset and only one side of the hollow fiber membrane 101 is washed. become unable.

Further, when a normal stirrer is used to eliminate the deviation of the bubbles A, a complicated mechanism such as a shaft seal of the stirrer and power supply is required.

The present invention has been made to solve the above-mentioned problems of the prior art. The purpose of the present invention is to improve the cleaning properties of the hollow fiber membrane and to protect the hollow fiber membrane. Is to provide a bubble disperser capable of facilitating manufacture.

[0011]

In order to achieve the above object, according to the present invention, a rotating member rotatably supported in a case accommodating a liquid and a liquid from below the rotating member are inserted into the liquid. It is characterized by comprising a bubble supply unit for supplying bubbles, and a rotating member drive means for converting the buoyancy of the bubbles into the rotating force of the rotating member.

[0012]

In the bubble disperser having the above-mentioned structure, the rotating member is rotated by the rotating member drive means for converting the buoyancy of the bubble supplied from the bubble supply unit into the rotating force, whereby the position where the bubble rises is moved. Thus, the bubbles are dispersed and supplied into the liquid.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to illustrated embodiments. FIG. 1 shows a bubble disperser according to an embodiment of the present invention. The bubble disperser 1 is attached to the bottom of a case 3 of a hollow fiber membrane module 2 shown in FIGS. 2 and 3.

First, the hollow fiber membrane module 2 shown in FIG. 2 will be described. This hollow fiber membrane module 2 is configured to adhere and fix the hollow fiber membranes 4 to each other while keeping one end of each hollow fiber membrane 4 in an open state at both end portions of a bundle of a large number of hollow fiber membranes 4. A hollow fiber membrane bundle 6 in which one end of each hollow fiber membrane 4 is opened and potted with a hollow fiber membrane bundle 6 in which a gap between the hollow fiber membranes 4 is sealed (potted) with a sealing material 5. A potting portion 8 having an end face 7 is suspended in the case 3 via a suspending member 9.

The case 3 has a housing portion 31 for housing the hollow fiber membrane bundle 6, a bottom portion 32 for closing one opening of the housing portion 31 and the bubble dispersing machine 1 attached thereto, and a housing portion 31.
Cap 3 on which the other opening of the hollow fiber membrane bundle 6 is suspended and the potting portion 8 of the hollow fiber membrane bundle 6 is suspended via the suspension member 9.
3 and 3.

The accommodating portion 31 is a tubular member having both ends open, and has outwardly facing flange portions 31A at both opening end portions, and the hollow fiber membrane bundle 6 is suspended. In this state, a stock solution supply port 10 for supplying a stock solution as a liquid to be filtered is provided in the case 3 on the side surface near the inner side in the axial direction of the potting portion 8. It has a bubble outlet 11 for letting out the bubble A from the case 3.

The bottom portion 32 has a disk shape and the diameter thereof is the storage portion 31.
The outer diameter of the flange portion 31A is substantially the same as that of the flange portion 31A, and an air nozzle 12 as a bubble supply portion for supplying the bubble A into the liquid in the case 3 is attached near the center thereof.

The cap 33 has a disk shape and a diameter of the storage portion 31.
The outer diameter of the flange portion 31A is substantially the same as that of the outer peripheral portion of the flange portion 31A. An annular convex portion 33A for attaching the member 9 is provided.

On the other hand, the suspension member 9 is composed of a convex portion 91 attached to the inner peripheral surface of the annular convex portion 33A of the cap 33, and a suspension portion 92 for suspending the potting portion 8 of the hollow fiber membrane bundle 6. ing. The suspension member 9 has the water collecting portion 15, and the outer peripheral surface of the convex portion 91 is liquid-tightly attached to the inner peripheral surface of the annular convex portion 32A via the O-ring 14 as a seal member. There is. A passage 9 is formed in the convex portion 91 so as to penetrate the water collecting portion 15 and the permeate outlet 13 in the axial direction.
Have three.

After the hollow fiber membrane bundle 6 is suspended,
The flange portion 31A of the housing portion 31 of the case 3 and the peripheral portion of the bottom portion 32 and the cap 33 are liquid-tightly tightened by the tightening member 16.

The hollow fiber membrane module 2 having the above structure is used in the field of sewage treatment, for example, and is used for filtration and the like in which pollutant D is relatively large. Filtration is performed as follows. That is, the stock solution is supplied into the case 3 from the stock solution supply port 10, and the stock solution is filtered by passing through the inside from the surface of each hollow fiber membrane 4 to obtain a permeate. The permeate is the hollow fiber membrane opening end surface. 7 is an external pressure type that flows out from the permeate outlet 13 through the water collecting portion 15 and the passage 93.

In such a filtration operation, each time the filtration pressure rises, the bubbles A are supplied into the liquid in the case 3 through the air nozzle 12, and as shown in FIG. As shown in FIG. 7B, bubble A is applied to each hollow fiber membrane 4 to remove the contaminants accumulated between the hollow fiber membranes 4, thereby performing bubble cleaning.

Next, a bubble disperser 1 according to an embodiment of the present invention used for the bubble cleaning will be described with reference to FIG.

This bubble disperser 1 is mounted in the vicinity of the air nozzle 12, and roughly has a dispersing blade 21 as a rotating member rotatably supported in a case 3 containing a liquid, and a bubble A. The rotary member drive means 20 for converting the buoyancy into the rotational force of the dispersion blade 21 is provided.

As shown in FIG. 1 (b), the dispersing blade 21 is formed by arranging two rectangular blades 22 on the outer peripheral surface of a cylindrical body portion 23 in an inclined manner. In addition, the blade 22 is 2
From the viewpoint of dispersion, not 6 sheets but 6 sheets is more preferable than 2 sheets.

The rotary member driving means 20 includes a shaft 25, a bearing 26 for the shaft 25 provided on the bottom 32 of the case 3, and a shaft 2.
5, the propeller 27 integrally attached to the blade 5, and the dispersing blade 2
And a fastening member 24 for fixing 1 to the shaft 25.

The propeller 27 is integrally provided at a midway portion of the shaft 25, and its length is such that the air nozzle 1 is mounted at the time of mounting.
The size is such that the buoyancy of the bubbles A supplied from 2 can be obtained. Then, one end of the shaft 25 with which the propeller 27 is integrated is inserted into a bearing 26 provided in the vicinity of the air nozzle 12, and is rotatably supported. The body portion 23 of the dispersing blade 21 is inserted into the other end portion of the shaft 25, and is integrally fixed via the tightening member 24.

In the bubble disperser 1 thus constructed, when the air bubble 12 is supplied into the liquid from the air nozzle 12, the propeller 27 receives the buoyancy of the air bubble A and the propeller 27 rotates. As a result, the dispersion blades 21
Rotates and the bubbles A supplied from below the dispersing blade 21 are dispersed by utilizing the flow created by the dispersing blade 21 due to the rotation. With the air bubbles A thus dispersed, cleaning is performed to remove the contaminant D accumulated between the hollow fiber membranes 4.

As a specific example of the bubble cleaning, the length L of the hollow fiber membrane 4 as shown in FIG. 3 is 800 to 1000 mm, the outer diameter d of the hollow fiber membrane bundle 6 is 80 mm, and the outer diameter D of the case 3 is: 100 mm
For cleaning the hollow fiber membrane module 2, the bubbles A are supplied (bubbled) for about 3 to 5 minutes at intervals of about 1 to 1.5 hours. The flow rate is about 800 Nl / hr. If the bubbling time is 3 minutes, 0.3 to 1 rpm is sufficient according to the bubble disperser 1.

In the bubble disperser having the above structure, the rotating member driving means 20 exerts a rotational force on the dispersing vanes 21, and the bubbles supplied from below by the flow created by the dispersing vanes 21 by this rotational force. Since the ascending position of A moves evenly, and the bubbles A do not remain unbalanced as in the prior art, the hollow fiber membrane 4 can be washed over the entire area and the cleaning performance is improved. be able to.

Further, since the air bubbles A move evenly and hit the hollow fiber membranes 4, the air bubbles A do not concentrate and hit the hollow fiber membranes 4, so that the protection property of the hollow fiber membranes 4 is improved.

Furthermore, since the air bubbles A move evenly and hit the hollow fiber membranes 4, even if the amount of the air bubbles A is slightly reduced, the washing performance is not significantly deteriorated, so that the operation can be stabilized.

The drive source of this bubble disperser is the bubble A.
Since it has the buoyancy, the structure of the drive system is not required, and thus the manufacturing can be facilitated.

FIG. 4 shows a second embodiment of the present invention. Although the rotating member is the dispersing blade 21 in the above-described embodiment, the conical umbrella member 21A is used in this embodiment, and the hole 2 penetrating in the middle of the peripheral surface of the umbrella member 21A is used.
1B.

When the umbrella member 21A is used as the rotating member in this manner, a bubble pool A0 is generated in the umbrella member 21A, but since the hole 21B is provided, the bubble A comes out from the hole 21B. Then, since the umbrella member 21A rotates, the position of the hole 21B moves in the rotation direction.
Therefore, the bubbles A move evenly.

In this embodiment, the air bubbles A are formed by the holes 21B.
Since the ascending position of No. 1 moves, it is possible to surely disperse the bubbles A evenly as compared with the first embodiment.

Since the other constructions and operations are the same as those of the first embodiment, the same components are designated by the same reference numerals and the description thereof will be omitted.

Further, FIG. 5 shows an umbrella member 21A 'which is another mode of the umbrella member 21A, which is provided with notches 21C instead of holes 21B. In this case, the preferred dimensional relationship is that the outer diameter of the umbrella member 21A 'is d1, the notch 21
When the inner diameter of C is d2 and the inner diameter of the storage part 31 is D1,
d1 = 0.8 to 0.9D1, d2 = 0.5 to 0.8d1
Is. The position of the supply source of the air nozzle 12 'is the storage portion 31 of the case 3.

FIG. 6 shows a third embodiment of the present invention. In this embodiment, the screw member 2 in which the rotary member driving means is wound around the shaft 25 and the blades 22A are spirally wound.
It is set to 0A. With such a structure, the rotating member becomes unnecessary, and the manufacture can be further facilitated.

In each of the above embodiments, the one used for the hollow fiber membrane module 2 has been described as an example, but the present invention is not limited to this.

[0041]

The present invention has the above-described configuration and operation. The rotating member driving means for converting the buoyancy of bubbles into the rotating force of the rotating member causes the rotating force to act on the rotating member. The rotating member rotates, the rising position of the bubbles supplied from the lower part of the rotating member moves evenly, and the bubbles do not remain unbalanced as in the prior art, so that the hollow fiber membrane is entirely covered. It can be washed, and the cleaning property can be improved.

Further, since the bubbles move uniformly and hit the hollow fiber membrane, the bubbles do not concentrate and hit the hollow fiber membrane, so that the hollow fiber membrane can be protected.

Further, since the air bubbles move uniformly and hit the hollow fiber membrane, even if the amount of the air bubbles is slightly reduced, the cleaning property is not greatly deteriorated, and the operation can be stabilized.

Since the drive source of this bubble disperser is the buoyancy of bubbles, there is no need to purposely construct a drive system, which facilitates production.

[Brief description of drawings]

FIG. 1 (a) is a schematic configuration diagram of a bubble disperser according to an embodiment of the present invention, and FIG. 1 (b) is a perspective view of a dispersion blade of FIG. 1 (a).

FIG. 2 is a schematic cross-sectional view of a hollow fiber membrane module to which the bubble disperser of FIG. 1 is applied.

FIG. 3 is a partially cutaway perspective view showing the dimensions of the hollow fiber membrane module.

4 (a) is a schematic cross-sectional view of a hollow fiber membrane module to which a bubble disperser according to a second embodiment of the present invention is applied, and FIG. 4 (b) shows the umbrella member of FIG. 4 (a). FIG.

FIG. 5 is a perspective view showing another aspect of the umbrella member.

FIG. 6 is a perspective view of an essential part of a bubble disperser according to a third embodiment of the present invention.

FIG. 7 (a) is a plan view showing a state in which contaminants are accumulated between the hollow fiber membranes, and FIG. 7 (b) is a plan view showing a state in which contaminants are removed by air bubbles. is there.

FIG. 8 is a schematic view of a hollow fiber membrane module representing conventional bubble cleaning.

9 (a) is a schematic perspective view of another conventional structure for cleaning air bubbles, and FIG. 9 (b) is a hollow fiber membrane module to which the structure of FIG. 9 (a) is applied. FIG.

[Explanation of symbols]

 1 Bubble Disperser 2 Hollow Fiber Membrane Module 3 Case 31 Storage Section 31A Flange Section 32 Bottom 33 Cap 33A Annular Convexion 4 Hollow Fiber Membrane 5 Sealant 6 Hollow Fiber Membrane Bundle 7 Hollow Fiber Membrane Open End Face 8, 17 Potting Section 9 Suspended member 91 Convex part 92 Suspended part 93 Passage 10 Undiluted solution supply port 11 Bubble outlet 12, 12 'Air nozzle (bubble supply part) 13 Permeate outlet 14 O-ring 15 Water collecting part 16 Tightening member 20 Rotating member drive Means 20A Screw-shaped member (rotating member driving means) 21 Dispersion blades (rotating member) 21A, 21A 'Umbrella member 21B Hole 21C Notch 22, 22A Blade 23 Body 24 Clamping member 25 Shaft 26 Bearing 27 Propeller

Claims (1)

[Claims] 1. A rotating member rotatably supported in a case accommodating a liquid, a bubble supply unit for supplying bubbles into the liquid from below the rotating member, and a buoyant force of the bubble as a rotating force of the rotating member. A bubble disperser, comprising: a rotating member driving means for converting.