JPH1133367A - Hollow yarn membrane module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformly and efficiently wash a hollow yarn membrane module and to enable the keeping of high filtering function over a long period of time by certainly supplying scrubbing air to the gaps between hollow yarn membrane knitted fabrics. SOLUTION: In a hollow yarn membrane module, a large number of hollow yarn membrane knitted fabrics 1 are arranged in parallel at a predetermined interval and one ends of hollow yarn membranes 30 constituting the hollow yarn membrane knitted fabrics 1 are fixed by a fixing member 2a while held to an open state and elements 1a sealed at the other ends thereof and an air supply header 8 for supplying air for washing the surfaces of the hollow yarn membranes 30 are provided in a container 3 and an air diffuser 10 for dispersing the guiding air supplied from the air supply header 8 is provided on the downstream side of the hollow yarn membrane knitted fabrics 1.

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 used for filtering highly polluting liquids such as river water, lake water, and industrial water, and wastewater treatment.

[0002]

2. Description of the Related Art Hollow fiber membrane modules are used in the field of microfiltration such as the production of sterile water, high-purity water, drinking water, and air purification, as well as secondary and tertiary treatment in sewage treatment plants, and septic tanks. It has also been applied to the field of highly polluting water treatment such as solid-liquid separation. In highly polluting water treatment,
Since the hollow fiber membrane module has a large clogging during filtration, after filtering for a certain period of time, air is sent from the bottom of the module to vibrate the hollow fiber membrane to wash the membrane surface, or filter water is filtered in the direction opposite to the filtration direction. Membrane washing such as backwashing with passing water is repeated.

[0003] However, when a hollow fiber membrane module in which hollow fiber membrane knitted fabrics are bundled and arranged on a columnar shape or concentric circles used for conventional microfiltration is used for high-pollutant water treatment, the processing time becomes longer. As a result, the hollow fiber membranes adhere to each other due to deposits such as organic substances attached to the membrane surface, the effective area of the hollow fiber membrane in the module decreases, the flow rate of filtration rapidly decreases, and the membrane is periodically cleaned. However, the membrane function is not easily recovered and the filtration efficiency is significantly reduced. As a solution to the reduction of the effective area and the reduction of the cleaning efficiency, as a solution of the hollow fiber membrane knitted fabric spread in a sheet shape, a rectangular flat fiber in which the hollow fiber membrane at one end or both ends is kept open and fixed to a frame. A hollow fiber membrane module of the type is proposed, and by arranging the hollow fiber membrane modules at appropriate intervals, the membrane surface can be easily washed, and a decrease in filtration efficiency can be suppressed. But,
When a flat hollow fiber membrane module is used for housing in a cylindrical container, the proportion occupied by parts other than the hollow fiber membrane increases, resulting in poor volumetric efficiency. And high cost.

[0004] In order to solve these problems, a plurality of flat hollow fiber membrane knitted fabrics are stacked in parallel or folded in a zigzag shape, accommodated in a module, and scrubbed with air supplied from an air header. A hollow fiber membrane module capable of maintaining a high filtration function for a long period of time has been proposed in JP-A-09-141063. However, in this module, the supplied air does not flow evenly between the hollow fiber membranes, causing a drift, or a plurality of air bubbles may rise together as a large bubble while rising. Was. Due to this phenomenon, the entire surface of the hollow fiber membrane is not washed, so that the recovery of the filtration function is not sufficient, and it is necessary to supply more air than necessary.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a flat hollow fiber membrane module housed in a container, which ensures uniform and efficient cleaning by reliably supplying air for scrubbing between the hollow fiber membrane knitted fabrics. An object of the present invention is to provide a cylindrical hollow fiber membrane module that maintains a high filtration function for a long period of time and easily recovers the filtration function.

[0006]

The gist of the present invention is that a plurality of hollow fiber knitted fabrics are arranged in parallel, and one end of a hollow fiber membrane constituting the hollow fiber membrane knitted fabric is fixed by a fixing member while maintaining an open state. A hollow fiber membrane module including an element fixed and the other end of which is sealed, a container accommodating the element, and an air supply header for supplying air into the container; The hollow fiber membrane module is characterized in that an air disperser for dispersing and guiding the generated air is provided below the hollow fiber membrane.

Further, according to the present invention, there is provided an element in which a plurality of hollow fiber membrane knitted fabrics are arranged in parallel, and at least one end of a hollow fiber membrane of the hollow fiber membrane knitted fabric is fixed by a fixing member while maintaining an open state; In a hollow fiber membrane module comprising a container accommodating the element, an air disperser for dispersing and guiding air is provided on a lower side of the hollow fiber membrane, and one end of the hollow fiber membrane is formed on the air disperser. The hollow fiber membrane module is provided, wherein the hollow fiber membrane module is inserted through the through hole and fixed in the air distributor by a fixing member.

[0008]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view showing an example of a hollow fiber membrane module of the present invention, FIG. 4 is a sectional view showing another example, and FIG. 6 is a perspective view showing an example of a hollow fiber membrane knitted fabric. Figures 1 and 4
The hollow fiber membrane module shown in FIG. 1 has a plurality of hollow fiber membrane knitted fabrics 1 arranged in parallel at a predetermined interval.
An element 1a in which one end (the upper end in the illustrated example) of the hollow fiber membrane 30 constituting the element 1a is fixed to the container 3 with the fixing member 2a while maintaining the open state, and the other end (the lower end in the illustrated example) is sealed.
And a gas supply header 8 for supplying air for cleaning the membrane surface of the hollow fiber membrane 30 in the hollow fiber membrane module, wherein the air supplied from the gas supply header 8 is provided. An air disperser 10 for dispersing and inducing air is provided below the hollow fiber membrane 30.

In the case of the hollow fiber membrane module shown in FIG. 1, the air distributor 10 is located below the hollow fiber 30, and the lower end of the hollow fiber membrane 30 has a through hole formed in the air distributor 10. 20 is not inserted. In contrast, in the case of the hollow fiber membrane module shown in FIG. 4, the air distributor 10 is located below the hollow fiber membrane 30, and the lower end of the hollow fiber membrane 30 passes through the through hole 20.

FIG. 5 is a sectional view showing another example of the hollow fiber membrane module of the present invention.
An element in which a plurality of hollow fiber membrane knitted fabrics 1 are arranged in parallel, and at least one end (both ends in the drawing) of the hollow fiber membrane 30 of the hollow fiber membrane knitted fabric 1 is fixed by fixing members 2a, 2b while maintaining an open state. In the hollow fiber membrane module comprising the element 1a and the container 3 accommodating the element 1a, an air disperser 40 for dispersing and guiding air is provided below the hollow fiber membrane 30, and one end of the hollow fiber membrane 30 is provided. The lower side (in the illustrated example) is inserted through the through hole 20 formed in the air distributor 40 and is fixed in the air distributor 40 by the fixing member 2b.

Hollow fiber membrane 30 constituting hollow fiber membrane knitted fabric 1
As, for example, polyolefin-based, cellulose-based, polyvinyl alcohol-based, polysulfone-based, polymethyl methacrylate-based materials such as those used,
Polyolefin-based hollow fiber membranes such as polyethylene having a high elongation and high elongation in terms of knitting properties to knitted fabrics are preferably used. The pore size, porosity, film thickness, outer diameter and the like of the hollow fiber membrane are not particularly limited as long as the membrane can be used as a filtration membrane.

The hollow fiber membrane knitted fabric 1 is based on any knitting method and weaving method as long as the hollow fiber membrane 30 is arranged on at least one of the warp and the weft and the function of the hollow fiber membrane is maintained. It may be something. Examples of the hollow fiber membrane knitted fabric are those in which the hollow fiber membrane is raschel knitted with overlock yarns, or, as shown in FIG.

In the case of the hollow fiber membrane module shown in FIGS. 1 and 4, the hollow fiber membrane 30 at one end (the upper end in the figure) of the hollow fiber membrane knitted fabric 1 is kept open and the container 3 is held by the fixing member 2a. A plurality of hollow fiber membrane knitted fabrics 1 are fixed in the upper part and arranged in parallel in the container 3 to form an element 1a. In this case, the other end (lower end) of the hollow fiber membrane 30 is closed to partition the hollow fiber channel 32 in the hollow fiber membrane 30 from the space on the raw water side. To make the closed state, the other end of the hollow fiber membrane 30 may be U-shaped (convex downward) or may be sealed by heat sealing, resin or the like.

On the other hand, in the case of the hollow fiber membrane module shown in FIG. 5, a plurality of hollow fiber membrane knitted fabrics 1 are arranged in parallel,
Both ends of the hollow fiber membrane 30 constituting the hollow fiber membrane knitted fabric 1 are kept open, one end of the hollow fiber membrane knitted fabric 1 is fixed in the container 3 by the fixing member 2a, and the other end is an air disperser 40.
The element 1a is fixed inside by a fixing member 2b.

When the hollow fiber membrane knitted fabric 1 is arranged in the container 3 so that the axial direction of the hollow fiber membrane 30 is vertical, the hollow fiber membrane 30 is efficiently scrubbed by air rising upward from below. You.

The fixing members 2a and 2b are made of a hollow fiber membrane knitted fabric 1.
And functions as a member for separating raw water and treated water without liquid leakage. For example, a urethane resin, an epoxy resin, an unsaturated polyester resin, or the like is used.

The arrangement interval of the hollow fiber membrane knitted fabric 1 is preferably 3 to 50 mm, more preferably 5 to 20 mm, from the viewpoint of the utilization efficiency, detergency and volumetric efficiency of the hollow fiber membrane 30.

In the example shown in FIGS. 1 and 4, an air supply header 8 is provided in the container 3, and the air supply header 8 transfers the air supplied from the air supply port 7 to the lower surface of the upper surface of the air distributor 10. Side, and for this purpose have holes. The material of the air supply header 8 and the material of the air distributor 10 may be the same.

The air disperser 10 used in the hollow fiber membrane module shown in FIGS.
Between the lower portion of the air supply header 8 and the air supplied from the air supply header 8 is dispersed and guided to the through holes 20;
This is for uniformly supplying air bubbles for scrubbing to the hollow fiber membrane 30.

The air disperser 10 may be a flat plate having a through hole in a flat plate, but as shown in FIGS. 1 and 4, has a cylindrical container shape having a side wall 21 extending downward from the upper surface. It is preferable that the portion has a through hole 20. When the air distributor 10 has the side wall 21, the lower surface of the upper surface of the air distributor 10 serves as an air receiver, and the air supplied from the air supply header 8 is once efficiently held on the lower surface. Once the air is held in this way, the supplied air is uniformly dispersed in the through holes 20, and the air can be dispersed and guided to the hollow fiber membrane 30.

In the case of the hollow fiber membrane module shown in FIG. 1, when the air disperser 10 is located directly below the hollow fiber membrane knitted fabric 1, the hollow fiber membrane 30 is efficiently moved by air bubbles rising from the through holes 20. Scrubbed.

The air disperser 40 used in the hollow fiber membrane module shown in FIG. 5 has a container shape having an upper surface, side walls 21 and partition walls 41, and has a through hole 20 on the upper surface and an air supply port on the side wall 21. 7 ′ has a filtered water outlet 5 in a partition wall 41, and the inside of the air distributor 40 is divided into two upper and lower chambers by a fixing member 2b, and the upper chamber is connected to the air supply port 7 ′. Hold the supplied air at one end and open through hole 2
The lower chamber is for taking out filtered water from the filtered water outlet 5. The partition (cylindrical) 41 and the fixing member 2b have an action of partitioning a space between the treated water side (the side communicating with the hollow fiber channel 32) and the raw water side.

The through holes 2 formed in the air distributors 10 and 40
0 is a slit-shaped through hole 20a as shown in FIG.
However, a circular hole 20b as shown in FIG.
The slit width and the hole diameter are appropriately determined based on the hollow fiber membrane knitted fabric 1 to be used, raw water properties, operating conditions, the amount of air used, and the like. The slit width and the hole diameter are preferably from 0.1 to 10 mm, more preferably 0.5 to 3 mm. If the through-hole 20 has a slit shape, the lower part of the hollow fiber membrane knitted fabric 1 can be easily inserted into the through-hole 20, and thus is preferable to the circular through-hole 20 b. As shown in FIG. 2, it is desirable that the slit-shaped through-hole 20a has a length of 10 times or more the slit width.

The materials of the air dispersers 10 and 40 are not particularly limited as long as they have corrosion resistance to highly polluted water of raw water, but synthetic resins such as polycarbonate resin, ABS resin, and polyvinyl chloride resin; Metals such as stainless steel can be used.

The container 3 in which the element 1a is housed is preferably a cylindrical container. If it is cylindrical, there is an advantage that the pressure resistance is excellent. The container 3 is not particularly limited as long as it has a corrosion resistance to the highly polluted water of the raw water and can be a pressure-resistant component at the time of treatment. For example, a polycarbonate resin, an ABS resin, a polyvinyl chloride resin, or the like can be used. It is made of metal such as synthetic resin and stainless steel. Further, the container 3 may have a structure that can be separated at an appropriate portion.

The element 1a and the container 3 may be integrated with a fixed member, but the element 1a may be detachably accommodated in the container 3 by an O-ring or the like so that the element 1a can be easily replaced.

Next, the operation of the hollow fiber membrane module shown in FIGS. 1 and 4 will be described. The raw water highly polluted water supplied from the raw water supply port 4 into the container 3 is a plurality of hollow water arranged in the element 1a. The water is filtered by the hollow fiber membrane 30 constituting the fiber membrane knitted fabric 1, enters the hollow fiber channel 32 formed in the hollow fiber membrane, and the filtered water passing through the hollow fiber channel 32 passes through the opening 33. Through the treated water outlet 5.

On the other hand, the air for scrubbing is supplied from the air supply port 7 to the air supply header 8, and the air supply header 8
Is spouted into the raw water from the through hole and reaches the lower surface of the air disperser 10, is dispersed in the through hole 20 by the air disperser 10, and then the through hole 20 of the air disperser 10 or the hollow fiber membrane The raw water rises through the gap between the fabric 1 and is distributed and guided between the suspended hollow fiber membrane knitted fabrics 1,
The hollow fiber membrane knitted fabric 1 is scrubbed while passing through in the form of bubbles to wash the surface of the hollow fiber membrane 30, and the air exits from the air outlet 9. Deposits such as organic substances separated from the hollow fiber membrane surface by scrubbing are taken out from the outlet 6.

In the case of the hollow fiber membrane module shown in FIG. 4, the lower portion of the hollow fiber membrane 30 is inserted through the through hole 20, so that air can be more uniformly supplied between the hollow fiber membrane fabrics. Therefore, the hollow fiber membrane module of FIG. 4 is scrubbed more efficiently than the hollow fiber membrane module of FIG.

Next, the operation of the hollow fiber membrane module shown in FIG. 5 will be described. In the hollow fiber membrane module,
As in the case of the hollow fiber membrane module shown in FIGS. Then, through the hollow fiber channel 32 and the openings 33, 33, the upper and lower treated water outlets 5, 5
Can be taken from The hollow fiber membrane 30 is opened at both upper and lower ends, and the in-vessel treated water hose 12 and the like are separated from the partition wall 4.
1, if the treated water is also taken out from the lower part of the container 3, the amount of water permeation can be improved.

On the other hand, the air for scrubbing is supplied from the air supply port 7 to the side surface of the upper chamber of the air distributor 40 by the hose hose 11 in the container or the like, reaches the lower surface of the upper surface of the air distributor 40, and then to the lower surface. , Through hole 20 of air disperser 40
Rises in the raw water through a gap between the hollow fiber membrane knitted fabric 1 and the hollow fiber membrane knitted fabric 1 fixed at the top and bottom. Knitted fabric 1
Is scrubbed to clean the surface of the hollow fiber membrane 30, and exits from the air outlet 9. Deposits such as organic substances separated from the hollow fiber membrane surface by scrubbing are taken out from the outlet 6.

Therefore, in the example of the hollow fiber membrane module shown in FIG. 5, since the air distributor 40 functions as both the air header 8 and the air distributor 10 shown in FIGS. Providing the air disperser 10 separately is
This is unnecessary in the example shown in FIG. Further, in the example shown in FIG. 5, since both ends of the hollow fiber membrane 30 are fixed, air can be more uniformly supplied to the membrane surface.
Is more efficiently scrubbed than the hollow fiber membrane module shown in FIG.

In this case, the partition 41 and the fixing member 2b are
The raw water side and the treated water side are partitioned by being fixed by bonding or screws.

[0034]

According to the hollow fiber membrane module of the present invention, the accumulation of organic substances between the hollow fiber membranes is suppressed, the hollow fiber membranes are prevented from sticking to each other, and even if the deposition occurs, the filtration is performed by uniform and efficient scrubbing. The function can be restored, and high filtration efficiency can be maintained for a long time.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first example of a hollow fiber membrane module of the present invention.

FIG. 2 is a perspective view showing an example of an air distributor having slit-shaped through holes.

FIG. 3 is a perspective view showing an example of an air disperser having a round hole.

FIG. 4 is a cross-sectional view showing a second example of the hollow fiber membrane module.

FIG. 5 is a sectional view showing a third example of the hollow fiber membrane module.

FIG. 6 is a perspective view showing an example of a hollow fiber membrane knitted fabric.

[Explanation of symbols]

1. .. hollow fiber membrane knitted fabric, 1a .. element, 2a, 2
b..fixing member, 3..container, 4 ... raw water supply port, 5.
・ Filtrated water outlet, 6 ・ ・ Sediment outlet, 7 ・ ・ Air supply port,
7 ′ ··· Air supply port, 8 ··· Air supply header, 9 ··· Air outlet, 10 ··· Air distributor, 10 ′ ··· Air distributor, 1
1 .... air hose in container, 12 ... treated water hose in container, 20 ... through hole, 20a ... slit-shaped through hole, 20
b ··· Round hole-shaped through hole, 21 ··· side wall, 30 ··· hollow fiber membrane, 31 ··· overlock thread, 32 ··· hollow fiber channel, 33 ···
Opening of hollow fiber membrane, 40 ... air disperser, 41 ... partition

Continued on the front page (51) Int.Cl. ⁶ Identification code FI C02F 1/44 C02F 1/44 K

Claims (2)

[Claims] 1. A plurality of hollow fiber membrane knitted fabrics are arranged in parallel,
An element in which one end of a hollow fiber membrane constituting the hollow fiber membrane knitted fabric is fixed by a fixing member while maintaining an open state and the other end is sealed, a container for housing the element, and air in the container. A hollow fiber membrane module including an air supply header for supplying air, wherein an air disperser for dispersing and guiding the air supplied from the air supply header is provided on a lower side of the hollow fiber membrane. And a hollow fiber membrane module. 2. A plurality of hollow fiber membrane knitted fabrics are arranged in parallel,
A hollow fiber membrane module comprising an element in which at least one end of a hollow fiber membrane of the hollow fiber membrane knitted fabric is fixed by a fixing member while maintaining an open state, and a container for accommodating the element, for dispersing and guiding air. Is provided on the lower side of the hollow fiber membrane, one end of the hollow fiber membrane is inserted through a through hole formed in the air disperser, and is fixed in the air disperser by a fixing member. A hollow fiber membrane module, comprising: