JPH09141063A - Hollow fiber membrane module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a module in which a high filtering function can be maintained for a long time and the filtering function can be easily recovered by arranging and fixing plural hollow fiber membrane woven fabrics parallel to each other to obtain an element, housing the element in a casing and then providing the case with an aeration header. SOLUTION: The end of a hollow fiber membrane woven fabric in which hollow fiber membranes are arranged as warps or wefts is fixed to a fixing member 2 while the end of the hollow fiber membrane is maintained as opened state, and plural numbers of hollow fiber membrane woven fabrics are arranged parallel to each other to obtain the obtd. element. The obtd. element is housed in a cylindrical casing 3 which is equipped with an aeration header 9 to supply air. A raw water which is highly contaminated and supplied from a raw water supply port 4 is filtered by the hollow fiber membrane in the hollow fiber membrane woven fabric 1. During this process, when air from an air supply port 8 is released through an aeration header 9, the air rises in a bubble state among the hollow fiber membrane fabrics 1 to clean the membrane surfaces. Thereby, a high filtering function can be maintained and recovered.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a hollow fiber membrane module used for filtering highly polluted water.

[0002]

2. Description of the Related Art Hollow fiber membrane modules are used in the fields of microfiltration such as sterile water, high-purity water, drinking water production and air filtration, as well as secondary treatment, tertiary treatment and septic tanks in sewage treatment plants. It has also been applied to the field of highly polluted water treatment such as solid-liquid separation in Japan. In highly polluted water treatment,
Since the hollow fiber membrane module has large clogging during filtration, after filtration 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 to pass water in the direction opposite to the filtration direction. Membrane cleaning such as cleaning is repeated.

However, when a hollow fiber membrane module in which a hollow fiber membrane knitted fabric is bundled and arranged in a columnar shape or concentric circles used for conventional microfiltration is used for highly polluted water treatment, the treatment time elapses. Along with this, the hollow fiber membranes are fixed to each other by the deposits such as organic substances adhering to the membrane surface, the effective membrane area of the hollow fiber membranes in the module is decreased, and the filtration flow rate is rapidly reduced, and also periodically. Even if the membrane is washed, the membrane function is not easily recovered, and the filtration efficiency is significantly reduced.

As a solution to the reduction of the effective membrane area and the reduction of the cleaning efficiency, the hollow fiber membrane knitted fabric is spread in a sheet shape, and one or both ends thereof are fixed to a frame while keeping the hollow fiber membrane open. A rectangular flat hollow fiber membrane module has been 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.

However, in the flat type hollow fiber membrane module, when it is housed in a cylindrical container, the ratio other than the hollow fiber membrane occupies a high ratio, so that the volume efficiency becomes poor, and when it is housed in a rectangular container. In order to obtain the pressure resistant structure, a reinforcing member is required, resulting in high cost. Further, in order to deal with a large amount of processing, it is necessary to integrate a plurality of hollow fiber membrane modules into a device, but this is expensive in manufacturing.

[0006]

DISCLOSURE OF THE INVENTION The present invention provides a hollow fiber membrane module having a flat type hollow fiber membrane module, which has a high volume efficiency in a cylindrical container and has a membrane cleaning function which has not been available in the past. The 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 is easy to recover the filtration function.

[0007]

The present invention is an element in which one end of a hollow fiber membrane knitted fabric is fixed by a fixing member while keeping the hollow fiber membrane open and the other end of the hollow fiber membrane is sealed. When,
A hollow fiber membrane module comprising a cylindrical container for accommodating an element, wherein a plurality of hollow fiber membrane knitted fabrics arranged in parallel and fixed are accommodated in the container, and an air supply header for supplying air is provided in the container. The hollow fiber membrane module is characterized in that

[0008]

DETAILED DESCRIPTION OF THE INVENTION The structure of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of an example of the hollow fiber membrane module of the present invention, and FIGS. 2 to 5 are perspective views of examples of elements constituting the hollow fiber membrane module. In the figure, 1 is a hollow fiber membrane knitted fabric, 2 is a fixing member, 3 is a cylindrical container, 4 is a raw water supply port, 5 is a treated water outlet, 6 is a sediment discharge port, 7 is an air outlet, and 8 is an air supply. Mouth, 9 air supply header, 10 spacer, 11 disk.

The hollow fiber membrane module of the present invention basically comprises an element in which a hollow fiber membrane knitted fabric 1 is fixed by a fixing member 2, a cylindrical container 3 and an air supply header 9. As the hollow fiber membrane constituting the hollow fiber membrane knitted fabric 1, those made of various materials such as polyolefin-based, cellulose-based, polyvinyl alcohol-based, polysulfone-based, polymethylmethacrylate-based, etc. are used. In this respect, a polyolefin-based hollow fiber membrane such as polyethylene having a high strength and elongation is preferably used. The hollow fiber membrane is not particularly limited in pore diameter, porosity, membrane thickness, outer diameter and the like as long as it can be used as a filtration membrane.

The hollow fiber membrane knitted woven fabric 1 is based on any knitting method or weaving method as long as the hollow fiber membrane is arranged on at least one of the warp yarn and the weft yarn and the function of the hollow fiber membrane is maintained. However, it is necessary that the hollow fiber membrane be fixed at one end of the knitted fabric by the fixing member and the other end of the hollow fiber membrane is sealed. Is.

The fixing member 2 fixes the hollow fiber membrane knitted woven fabric 1 and functions as a member for partitioning raw water and treated water without liquid leakage. For example, urethane resin, epoxy resin, unsaturated polyester resin or the like is used. To be

In the element of the present invention, as shown in FIG. 2, one end of the hollow fiber membrane knitted fabric 1 is fixed by the fixing member 2 while keeping the hollow fiber membrane at the end in an open state, and A plurality of membrane knitted fabrics 1 are arranged in parallel and fixed to each other. The hollow fiber membrane at the other end of the hollow fiber membrane knitted fabric 1 is closed in a U shape, or is sealed by heat sealing, resin or the like to be in a closed state. The arrangement interval of the hollow fiber membrane knitted fabrics 1 depends on the utilization efficiency of the hollow fiber membranes, the washability,
From the viewpoint of volumetric efficiency, it is preferably 3 to 50 mm, more preferably 5 to 20 mm.

In order to arrange and fix a plurality of hollow fiber membrane knitted fabrics 1 in parallel, a plurality of hollow fiber membrane knitted fabrics 1 may be arranged in parallel and fixed, but as shown in FIG. The yarn film knitted fabric 1 may be folded back a plurality of times to form a parallel state and be fixed.

Further, as shown in FIG. 4, a spacer 10 having an appropriate width may be interposed between adjacent hollow fiber membrane knitted fabrics 1 and a plurality of hollow fiber membrane knitted fabrics 1 may be arranged in parallel and fixed. Then, as shown in FIG. 5, the hollow fiber membrane knitted fabric 1 may be inserted into a plurality of parallel slits provided in the disc 11 at appropriate width intervals and arranged in parallel and fixed.

The fixing of the hollow fiber membrane knitted fabric 1 by the fixing member 2 may be carried out by temporarily fixing the hollow fiber membrane knitted fabric 1 with a jig or the like and then fixing it by the fixing member 2. Used element or disk with slit 11
Since the element using is not required to be temporarily fixed in manufacturing, the element manufacturing work is facilitated, and since the spacer 10 or the disk 11 is embedded in the fixing member 2, the strength of the fixing portion can be improved. It is preferable to use a method using a disk having a spacer or a slit.

The cylindrical container 3 in which the elements are housed is
There is no particular limitation as long as the material has corrosion resistance to highly polluted water of raw water and can be a pressure resistant constituent material during treatment, but is not limited to synthetic resins such as polycarbonate resin, ABS resin, polyvinyl chloride resin, and stainless steel. The cylindrical container 3 is made of a metal such as steel, and has a raw water supply port 4, a treated water outlet 5, a sediment discharge port 6, an air outlet 7, and an air supply port 8. Further, the cylindrical container 3 may have a structure that can be separated at appropriate portions.

The element and the cylindrical container 3 may be integrated with each other by the fixing member 2, but the element is replaced by an O-ring or the like so that the element can be easily replaced.
It may be detachably stored in the.

In the cylindrical container 3, an air supply header 9 for supplying air is preferably provided at the end of the housed element of the hollow fiber membrane knitted fabric 1 where the hollow fiber membrane is closed. The raw water supply port 4 is located in between and deployed.

In the hollow fiber membrane module of the present invention,
The highly polluted water of the raw water supplied from the raw water supply port 4 is filtered by the hollow fiber membranes of the hollow fiber membrane knitted fabric 1 arranged in a plurality of elements and exits from the treated water outlet 5 as filtered treated water. On the other hand, the air supplied from the air supply port 8 is discharged from the air supply header 9 and scrubs the hollow fiber membrane knitted fabric 1 while passing between the hollow fiber membrane knitted fabrics 1 in the form of bubbles to form a hollow fiber membrane. The membrane surface is cleaned and the air is discharged from the air outlet 7. Deposits such as organic substances separated from the hollow fiber membrane surface by scrubbing are taken out from the deposit discharge port 6.

[0020]

INDUSTRIAL APPLICABILITY The hollow fiber membrane module of the present invention can suppress the deposition of organic substances between the hollow fiber membranes, prevent the hollow fiber membranes from sticking to each other, and can maintain a high filtration efficiency for a long period of time. Further, even if accumulation occurs, the air scrubbing can easily and efficiently restore the filtration function.

[Brief description of the drawings]

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

FIG. 2 is a perspective view of an example of an element forming a hollow fiber membrane module.

FIG. 3 is a perspective view of another example of an element constituting the hollow fiber membrane module.

FIG. 4 is a perspective view of another example of an element forming the hollow fiber membrane module.

FIG. 5 is a perspective view of another example of an element constituting the hollow fiber membrane module.

[Explanation of symbols]

 1 Hollow Fiber Membrane Knitted Fabric 2 Fixing Member 3 Cylindrical Container 4 Raw Water Supply Port 5 Treated Water Outlet 6 Deposit Discharge Port 7 Air Outlet 8 Air Supply Port 9 Air Supply Header 10 Spacer 11 Disk

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication C02F 1/44 C02F 1/44 H

Claims (4)

[Claims] 1. An element in which one end of a hollow fiber membrane knitted fabric is fixed by a fixing member while keeping the hollow fiber membrane in an open state and the other end of the hollow fiber membrane is sealed, and a cylindrical shape for accommodating the element. A hollow fiber membrane module comprising a container, wherein a plurality of hollow fiber membrane knitted fabrics arranged in parallel and fixed are housed in the container, and an air supply header for supplying air is provided in the container. Hollow fiber membrane module. 2. The hollow fiber membrane module according to claim 1, wherein a plurality of hollow fiber membrane knitted fabrics are folded back and arranged in parallel and fixed. 3. The hollow fiber membrane module according to claim 1, wherein a plurality of hollow fiber membrane knitted fabrics are arranged and fixed in parallel with each other with a spacer interposed between adjacent hollow fiber membrane knitted fabrics. 4. The hollow fiber membrane module according to claim 1, wherein the hollow fiber membrane knitted fabric is inserted into a plurality of parallel slits provided in a disk and arranged in parallel and fixed.