JP2001205054A - Hollow fiber membrane module and hollow fiber membrane module unit using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hollow fiber membrane module in which the cleaning of membrane surfaces is easy and which is particularly suitable for filtering a liquid of high turbidity due to organic substances and a hollow fiber membrane module unit using the module. SOLUTION: In the hollow fiber membrane module, one end part or both end parts of the hollow fiber membrane formed in the shape of a sheet are fixed by a fixing member in a housing while the hollow fiber membrane is opened. The module is arranged so that the longitudinal direction of the hollow fiber membrane of the module is perpendicular. In the hollow fiber membrane module unit, such module is used.

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 suitable for use in filtering a liquid having a particularly high turbidity (contamination by an organic substance), and uses the hollow fiber membrane module. The present invention relates to a hollow fiber membrane module unit.

[0002]

2. Description of the Related Art Conventionally, filtration using a hollow fiber membrane module has been frequently performed in the field of so-called microfiltration such as production of sterile water, drinking water or high-purity water, and purification of air. Various studies have been made on application to secondary and tertiary treatment in a treatment plant and treatment of highly polluted water such as solid-liquid separation in a septic tank.

[0003] The hollow fiber membrane module used in such an application has a large clogging of the hollow fiber membrane during the filtration treatment.
After filtration for a certain period of time, air must be sent to vibrate the hollow fiber membrane to wash the membrane surface, or the membrane surface must be washed repeatedly by passing treated water in the opposite direction to the filtration process. .

The hollow fiber membrane module used in these fields is a cylindrical type in which hollow fiber membranes which are used in the field of conventional microfiltration are arranged in a circular or concentric manner. Almost. Even if improvements are made, there are many that only change the filling rate or filling form of the hollow fiber membrane.

[0005]

SUMMARY OF THE INVENTION Using the conventional hollow fiber membrane module as described above, highly polluting water (for example, ss ≧
When a filtration treatment of 50 mg / L, TOC ≧ 100 mg / L) is performed, organic substances and the like adhere to and accumulate on the surface of the hollow fiber membrane with the progress of use of the hollow fiber membrane module. The films are fixed (adhered) and integrated. As a result, the effective membrane area of the hollow fiber membrane in the hollow fiber membrane module decreases, and the filtration flow rate sharply decreases. Further, even if the membrane surface cleaning and backwashing of the hollow fiber membranes are performed regularly, the hollow fiber membranes adhere to each other as described above,
If they are integrated, it is not easy to recover the function of the module, and the cleaning efficiency is reduced.

As a solution to this problem, a hollow fiber membrane is arranged in a sheet form in place of a bundled cylindrical hollow fiber membrane module, and one end or both ends of the hollow fiber membrane forming a sheet are A fixing member in one or two different housings, each of which comprises a hollow fiber membrane module which is fixed while maintaining the open state of the hollow fiber membrane, and each of the fixing members has a cross section perpendicular to the hollow fiber membrane, There has been proposed a hollow fiber membrane module having an elongated and substantially rectangular shape.

The flat-type hollow fiber membrane module in which the hollow fiber membranes are arranged in a sheet shape can arrange the sheet-shaped hollow fiber membranes at regular intervals in the inner and outer layers. When the surface is washed, it is extremely easy to evenly wash the surface of the hollow fiber membrane, and it is possible to suppress a decrease in filtration efficiency. Therefore, it is suitable for use in filtering highly polluted water.

When treating a large volume (for example, 1 m ³ / h) of water using a flat hollow fiber membrane module in which the hollow fiber membranes are arranged in a sheet form, it is necessary to increase the membrane area. However, when the membrane area of the hollow fiber membrane module is increased, handling becomes difficult, the processing tank becomes unnecessarily large, and the hollow fiber membranes are accumulated. There is a problem that the entire membrane surface in the module cannot be efficiently cleaned with air or the like.

Further, as a method of using a conventional flat hollow fiber membrane module in which hollow fiber membranes are arranged in a sheet shape, there is a case where the number of modules is increased to increase the membrane area and the module is unitized. Is the arrangement of the hollow fiber membrane modules in the unit (that is, the interval between the modules when the modules are arranged in parallel so that the sheet-like hollow fiber membranes are superposed) There is also a problem that there is a limit in reducing the distance between the hollow fiber membrane modules because it is governed by the diameter.

Therefore, the interval between the hollow fiber membrane modules (the interval between the sheet-shaped hollow fiber membranes in the case of the flat hollow fiber membrane module using the sheet-shaped hollow fiber membrane) is unnecessarily widened, and the interval is accordingly increased. There is a problem that the volume of the processing tank becomes larger than necessary, or that the amount of bubbling for scrubbing must be increased.

Accordingly, it is an object of the present invention to provide a compact structure with a small space occupied by the water collecting portion even if the membrane area of the hollow fiber membrane is increased, and to scrub and clean the entire hollow fiber membrane in the module. And a hollow fiber membrane module unit using the hollow fiber membrane module, which is capable of efficiently performing the process.

[0012]

The above object can be achieved by the hollow fiber membrane module of the present invention having the following configuration, and a hollow fiber membrane module unit using the hollow fiber membrane module. That is, the hollow fiber membrane module of the present invention is a hollow fiber membrane module in which one end or both ends of a sheet-shaped hollow fiber membrane is fixed by a fixing member in a housing while maintaining an open state of the hollow fiber membrane. And the hollow fiber membrane module is arranged so that the length direction of the hollow fiber membrane of the hollow fiber membrane module is vertical.

In the hollow fiber membrane module of the present invention having the above-described structure, it is preferable that a plurality of sheet-like hollow fiber membranes are arranged, and that the fixing member is fixed to the water collecting pipe.

The hollow fiber membrane module unit of the present invention comprises:
A plurality of hollow fiber membrane modules having the above configuration are arranged in parallel or stacked.

Further, the hollow fiber membrane module unit of the present invention is a hollow fiber membrane module unit in which a plurality of the hollow fiber membrane modules of the present invention having the above structure are arranged in parallel, and In the first hollow fiber membrane module and the second hollow fiber membrane module arranged adjacent to each other, the second hollow fiber membrane among the sheet-like hollow fiber membranes in the first hollow fiber membrane module A sheet-shaped hollow fiber membrane disposed on the module side;
The distance between the sheet-shaped hollow fiber membrane and the sheet-shaped hollow fiber membrane that is arranged closest to the first hollow fiber membrane module side in the hollow fiber membrane module of (5) is 5 to 10
It is at 0 mm.

Further, in the hollow fiber membrane module unit having the above structure, it is preferable that the hollow fiber membrane module unit is provided with an air diffuser tube integrally therewith.

Hereinafter, a specific configuration of the hollow fiber membrane module of the present invention and a hollow fiber membrane module unit using the hollow fiber membrane module will be described with reference to the drawings.

FIG. 1 shows an example in which eight hollow fiber membranes formed of a hollow fiber membrane knitted fabric are used. One end of each hollow fiber membrane is fixed with a fixing member while maintaining the open state of the hollow fiber membrane. FIG. 3 is a perspective view of a fixed hollow fiber membrane module, in which the shape of a cross section perpendicular to the hollow fiber membrane of the fixing member is elongated and substantially rectangular, and the hollow fiber membrane module is a side where the hollow fiber membrane is exposed from the fixing member. Where A is the area of the fixing member surface and B is the area of the fixing member end surface where the hollow fiber membrane is open, 100 ≧
The relationship of A / B ≧ 1.2 is satisfied, and A / B is set to 1.7 in the hollow fiber membrane module shown in FIG.

FIG. 2 shows a state in which both ends of each hollow fiber membrane are opened by using eight sheet-like hollow fiber membranes made of a hollow fiber membrane knitted fabric as in FIG. It is a perspective view of the hollow fiber membrane module fixed with the fixing member while keeping.

FIG. 3 is a sectional view of the hollow fiber fixing portion in a direction perpendicular to the longitudinal direction of the water collecting pipe of the hollow fiber membrane module shown in FIGS.

In FIGS. 1 to 3, reference numeral 3 denotes an opening end surface of the hollow fiber membrane, reference numeral 5 denotes a hollow fiber membrane knitted fabric in a sheet shape, reference numeral 6 denotes a housing and a water collecting pipe, reference numeral 7 denotes a fixing member, and reference numeral 8 Denotes a water pipe, and reference numeral 9 denotes a filtrate outlet.

As illustrated in FIGS. 1 and 2, a sheet-like hollow fiber membrane made of a knitted hollow fiber membrane is used, and one end or both ends of the hollow fiber membrane maintain the open state of the hollow fiber membrane. In a hollow fiber membrane module which is fixed by a fixing member in the structural material while the cross section perpendicular to the hollow fiber membrane of the fixing member is elongated and substantially rectangular, the fixing member on the side where the hollow fiber membrane is exposed from the fixing member When the area of the surface is A and the area of the end surface of the fixing member where the hollow fiber membrane is open is B, 100 ≧ A
By making the hollow fiber membrane module satisfying /B≧1.2, the space occupied by the water collecting portion is reduced even if the membrane area of the hollow fiber membrane is increased, thereby providing a hollow fiber membrane module having a compact structure. It becomes possible to do.

The hollow fiber membrane knitted fabric 5 serving as a sheet-shaped hollow fiber membrane can be made of various materials such as cellulose, polyolefin, polyvinyl alcohol, and polysulfone. Particularly, a material made of a material having a high elongation such as polyethylene or polypropylene is preferable.

The hollow fiber membrane is not particularly limited as long as it can be used as a filtration membrane, and there are no particular restrictions on the pore size, porosity, film thickness, outer diameter, etc. From the viewpoints of securing the strength and strength of the hollow fiber membrane, the pore size is 0.01 to 1 μm.
m, porosity 20 to 90%, film thickness 5 to 300 μm, outer diameter 2
0-2000 μm is preferred. In particular, when the purpose is to remove bacteria, the pore size must be 0.2 μm or less. When the purpose is to remove organic substances and viruses, the molecular weight cutoff is limited to tens of thousands to hundreds of thousands. An external filtration membrane may be used.

As the surface characteristics of the hollow fiber membrane, a so-called permanent hydrophilized membrane having a hydrophilic group or the like on its surface is desirable. As a method for producing a permanent hydrophilic membrane, a method for producing a hollow fiber membrane with a hydrophilic polymer such as a polyvinyl alcohol-based membrane,
Alternatively, a known method such as a method of hydrophilizing the surface of the hydrophobic polymer film can be used. For example, examples of the hydrophilic polymer when the hydrophilic polymer is hydrophilized by applying the hydrophilic polymer to the membrane surface of the hydrophobic hollow fiber membrane include a saponified ethylene-vinyl acetate copolymer, polyvinylpyrrolidone, and the like. be able to.

Examples of the film surface hydrophilization by another method include:
There is a film surface polymerization method of a hydrophilic monomer, and examples of this monomer include diacetone acrylamide.

As still another technique, a hydrophilic polymer is blended with a hydrophobic polymer (for example, polyolefin),
A method of spinning the film into a film can be used, and examples of the hydrophilic polymer that can be used include those described above.

When the surface of the hollow fiber membrane is hydrophobic, hydrophobic interaction acts between the organic matter in the water to be treated and the surface of the hollow fiber membrane, and organic substances are adsorbed on the membrane surface. Blockage, and the filtration life is shortened. In addition, it is generally difficult to recover filtration performance by cleaning the membrane surface due to clogging caused by adsorption.

On the other hand, when the permanent hydrophilizing membrane is used, the hydrophobic interaction between the organic substance and the surface of the hollow fiber membrane can be reduced, and the adsorption of the organic substance can be suppressed. Furthermore,
In the scrubbing cleaning during use in the hydrophobic membrane, the bubbling air causes drying and hydrophobicity, which may cause a decrease in the flux. However, the permanent hydrophilized membrane does not cause a decrease in the flux even when dried. .

As shown in FIGS. 1 and 2, the hollow fiber membrane may be fixed at one end or both ends of the sheet-shaped hollow fiber membrane, and either fixing means may be used depending on the purpose and application. You can choose.

The hollow fiber membrane module of the present invention utilizes a sheet-like hollow fiber membrane, and is arranged such that the length of the hollow fiber membrane of the hollow fiber membrane module is vertical. Is what is being done. By using a hollow fiber membrane module that is arranged so that the length direction of the hollow fiber membrane is vertical, air bubbles used for scrubbing cleaning rise along the membrane surface without receiving large resistance from the membrane surface As a result, the rising speed of the air bubbles is increased, and the hollow fiber membrane module can be efficiently cleaned.

On the other hand, if the hollow fiber membrane module is arranged so that the length direction of the hollow fiber membrane of the hollow fiber membrane module is horizontal or oblique, air bubbles used for scrubbing and washing are reduced. When the air bubble rises, it collides with the hollow fiber membrane surface one after another, so that the rising speed of the air bubble becomes slow, resulting in poor cleaning efficiency.

Further, for example, when performing filtration of sewage drainage, which contains fibrous contaminants such as hair and washing waste in the water to be treated, the length direction of the hollow fiber membrane may be horizontal or oblique. When the hollow fiber membrane module is arranged,
These fibrous contaminants are easily entangled with the hollow fiber membrane, and the entangled portion is difficult to be scrubbed and washed, whereby the surface of the hollow fiber membrane is likely to be closed.

On the other hand, as described above, the hollow fiber membrane module is arranged so that the length direction of the hollow fiber membrane is vertical, so that the fibrous contaminants are removed from the hollow fiber membrane. The hollow fiber membrane module is less likely to be entangled with the hollow fiber membrane, so that the membrane surface of the hollow fiber membrane is less likely to be blocked.

The hollow fiber membrane knitted fabric 5 as a sheet-shaped hollow fiber membrane is formed by knitting a hollow fiber membrane into a sheet.
This sheet-shaped hollow fiber membrane is, for example,
It can be easily manufactured by using the apparatus and method described in JP-A-886-86 and JP-A-63-91673.

In FIG. 3, the end face 3 of the opening of the hollow fiber membrane is a portion for taking out the filtrate from this end face and sending the filtrate to a water pipe or the like. The housing and the water collecting pipe 6 function as a whole support member in the hollow fiber membrane module shown in FIGS. 1 and 2 and have an elongated, substantially rectangular opening.
The opening of the housing and the water collecting pipe 6 has a cross section perpendicular to the hollow fiber membrane of the fixing member filled and fixed with the hollow fiber membrane therein, and has an elongated substantially rectangular shape.

The fixing member 7 is filled and fixed in the opening of the housing and the water collecting pipe 6, and is formed so as to have a shape as shown in FIG. 3, but any shape may be used. Absent. The fixing member 7 converges and fixes each end of the large number of hollow fiber membranes while maintaining the open state of the hollow fiber membranes, and performs processing on the hollow fiber membranes so that the hollow fiber membranes function as a filtration membrane. It functions as a member that partitions water and treated water in a liquid-tight manner.

The fixing member 7 is usually formed by curing a liquid resin such as an epoxy resin, an unsaturated polyester resin, and polyurethane. The water conduit 8 is a pipe through which the filtrate flows, and communicates with the filtrate outlet 9.

The material of the housing, the water collecting pipe 6 and the water guiding pipe 8 may be any material having mechanical strength and durability. For example, hard polyvinyl chloride resin, polycarbonate, polysulfone, polypropylene, acrylic resin, ABS And modified PPE resin. If incineration is required after use, it is preferable to use a hydrocarbon-based resin material that can be completely burned without emitting toxic gas by combustion.

An arbitrary value is selected for the ratio of the area A of the fixing member surface on the side where the hollow fiber membrane is exposed from the fixing member to the area B of the fixing member end surface where the hollow fiber membrane is open, ie, A / B. However, considering the processing capacity, the membrane area, the size of the can or the processing tank, the handleability, the number of sheet-like hollow fiber membranes, and the inner and outer diameters of the water collecting pipe, the value of A / B is 1 .2
It is preferably within the range of 100.

The hollow fiber membrane module of the present invention has the following features. That is, since the hollow fiber membranes are evenly arranged on the entire surface of the fixing member represented by the area A, the area B is the same, and the A / B is 1 between the hollow fiber membranes. This makes it difficult for the accumulation of turbidity and adhesion between the hollow fiber membranes to occur, so that the membrane surface can be effectively used and scrubbing and cleaning can be performed efficiently.

Even if the number of hollow fiber membrane modules is the same, the hollow fiber membrane module of A / B> 1 requires less resin to be used as a fixing member than the A / B = 1. Can be made. Therefore, in the case of a resin which generates heat during curing, the smaller the amount of the resin, the less heat is generated, the smaller the curing shrinkage and the easier the molding.

A hollow fiber membrane module using a sheet-like hollow fiber membrane made of a hollow fiber membrane knitted fabric as shown in FIGS. 1 and 2, that is, using a sheet-like hollow fiber membrane, and
Even a hollow fiber membrane module in which the value of B is in the range of 1.2 to 100 is more excellent in handleability than a hollow fiber membrane module having a similar membrane area, and a sheet made of a hollow fiber membrane knitted fabric. Since the hollow fiber membranes can be uniformly arranged inside and outside at intervals, it is extremely easy to evenly clean the surface of the hollow fiber membrane when cleaning the membrane surface.

Furthermore, the effect can be further improved by forming a hollow fiber membrane module in which the intervals between sheet-like hollow fiber membranes made of the respective hollow fiber membrane knitted fabrics are equally spaced.

In the case where a plurality of hollow fiber membrane modules are arranged in a treatment tank or the like to form a hollow fiber membrane module unit, a hollow fiber membrane made of a knitted hollow fiber membrane is arranged in parallel so that sheet-like hollow fiber membranes are superposed. Moreover, when all the sheet-like hollow fiber membranes in all the hollow fiber membrane modules are fixed at equal intervals, the hollow fiber membrane module unit can perform uniform scrubbing and cleaning of the entire hollow fiber membrane, and a partial The filter efficiency is not reduced.

When the depth of the treatment tank has a margin with respect to the height of the hollow fiber membrane module, a plurality of hollow fiber membrane modules are stacked and arranged in the depth direction of the treatment tank. It is also possible to use a hollow fiber membrane module unit.

Further, it is also possible to use a plurality of hollow fiber membrane module units in which a plurality of the above hollow fiber membrane modules are arranged side by side in the lateral direction and stacked in the depth direction of the treatment tank.

When the processing tank can be deepened,
If the hollow fiber membrane module units are stacked and used in the depth direction, the installation area of the processing tank can be reduced as compared with the case where a shallow processing tank is used, and the air used for scrubbing is limited. The area can be concentrated, and a hollow fiber membrane module unit having higher washing efficiency can be obtained.

In a conventional hollow fiber membrane module unit,
The distance between the modules is governed by the outer diameter of the collecting pipe or the size of the connection at the filtrate outlet of the collecting pipe. On the other hand, the width of the fixing member is made larger than the outer diameter and the connecting portion of the water collecting pipe, and the hollow fiber membrane module unit in which a plurality of modules are arranged in parallel so that the side surfaces of the fixing member are in contact with each other. By doing so, it becomes possible to fix the sheet-like hollow fiber membranes composed of all the hollow fiber membrane knitted fabrics in all the hollow fiber membrane modules at equal intervals, and thereby to perform even scrubbing and cleaning over the entire hollow fiber membrane. The hollow fiber membrane module unit can be performed without causing a partial decrease in filtration efficiency.

The intervals between the sheet-like hollow fiber membranes made of the hollow fiber membrane knitted fabric in the hollow fiber membrane module are made equal, considering that air bubbling during scrubbing is evenly applied to the entire membrane surface. It is desirable that the interval can be set arbitrarily, but in consideration of the efficiency of scrubbing cleaning in air bubbling, the prevention of adhesion of adjacent hollow fiber membrane knitted fabric, the membrane area per module, etc. The interval (distance) between the thread membranes is 5 to
Preferably it is 100 mm.

That is, if the interval between sheet-like hollow fiber membranes made of a knitted hollow fiber membrane is smaller than 5 mm, the hollow fiber membranes become too dense and the washing performance deteriorates.
When the ratio exceeds, the decrease in the membrane area per volume occupied by the filtration device becomes remarkable.

Further, by fixing the sheet-like hollow fiber membranes made of the hollow fiber membrane knitted fabric at a predetermined interval for each sheet, it becomes more difficult for the hollow fiber membranes to be fixedly integrated. I can do it.

When a flat hollow fiber membrane module using a sheet-shaped hollow fiber membrane made of a hollow fiber membrane knitted fabric is used, the hollow fiber membrane module is disposed in a closed container, and the water to be treated is pressurized to form a hollow fiber membrane. So-called pressure filtration that allows the fiber membrane to permeate can be performed, but suction filtration is performed by arranging a hollow fiber membrane module in an activated sludge tank or sedimentation tank, etc., and suctioning the side that collects treated water that has passed through the hollow fiber membrane. Is more preferable.

In particular, by adopting a filtration method based on a so-called intermittent suction operation method in which the temporary suction is periodically stopped, it is possible to efficiently prevent the film surface deposits from entering the inside of the film surface, and the The frequency of processing for restoring the function of the thread membrane module can be reduced.

The intermittent interval at the time of intermittent suction differs in the optimum range depending on the turbidity of the water to be treated, so that a clear range cannot be defined. However, when the activated sludge of about MLSS 5000 mg / L is targeted. Is a suction time of 1 to 30 minutes,
The stop time is preferably in the range of 2 seconds to 15 minutes.

Further, by performing the suction filtration method, it becomes easy to circulate the treated water in the tank at the time of filtration or to wash the membrane surface by performing air bubbling. In particular, as described above, the cleaning method by air bubbling can further improve the cleaning effect by combining with the intermittent suction operation method that can efficiently prevent the film surface deposit from entering the inside of the film surface. . It is preferable that the flow of the water to be treated in the suction filtration method be substantially parallel to the length direction of the hollow fiber membrane to enhance the cleaning effect of the membrane surface of the hollow fiber membrane.

In filtration of highly polluted water, many s
s and organic matter are deposited. For that purpose, it is necessary to remove the deposit using a water flow, air, vibration, ultrasonic waves, or the like, and to clean the film surface. If the cleaning is not performed, the organic matter deposited on the membrane surface will cause blockage of the membrane, resulting in a reduction in filtration life. Specific cleaning methods include a so-called cross-flow filtration in which a water flow is made parallel to the membrane surface, a method of generating a water flow in a membrane module immersion tank by a pump or a motor, a bubbling method using an upward flow of air, and vibration of the module itself. And a method of vibrating the liquid to be treated by ultrasonic waves. These washings, depending on the progress of the membrane surface blockage,
It may be performed continuously or intermittently.

In the case of operating while simultaneously performing scrubbing cleaning by air bubbling, a diffuser for performing bubbling is required. To perform proper air bubbling, the positional relationship between the diffuser and the module unit is important, but fixing the module unit and the diffuser tube separately is a complicated operation, and the module unit may move during operation. If so, there is a problem that it becomes impossible to perform appropriate scrubbing cleaning during operation. As a countermeasure, by using a hollow fiber membrane module unit fixedly integrated with the air diffuser, it can be easily attached to the can or the treatment layer, and appropriate scrubbing cleaning can be continued during operation. .

The filtration treatment using the hollow fiber membrane module of the present invention is particularly suitable for filtering highly polluted water. Specific application fields include river water filtration and industrial tap water. Examples of the method include filtration, solid-liquid separation of sewage, and wastewater treatment (for example, treatment in a combined septic tank).

[0060]

The hollow fiber membrane module of the present invention has a large membrane area and a compact structure, and more hollow fiber membranes come into direct contact with the water to be treated. For this reason, in the filtration treatment using the hollow fiber membrane module of the present invention, it is possible to effectively prevent adhesion and integration between the hollow fiber membranes, particularly when filtering highly polluted water. However, high filtration efficiency can be maintained for a long time.

In particular, when the hollow fiber membrane module of the present invention, which uses a sheet-like hollow fiber membrane made of a hollow fiber membrane knitted fabric, is immersed in a treatment tank and subjected to filtration, the length of the hollow fiber membrane is reduced. Since all the hollow fiber membrane knitted fabrics can be arranged at equal intervals so that the direction is the vertical direction, the hollow fiber membrane module unit including a plurality of hollow fiber membrane modules can be used. An even and efficient scrubbing cleaning can be performed throughout the unit.

Further, the hollow fiber membrane module of the present invention can be easily attached to and detached from a can or a processing tank, and is excellent in handleability.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a hollow fiber membrane module.

FIG. 2 is a perspective view showing another example of the hollow fiber membrane module.

FIG. 3 is a sectional view of a hollow fiber membrane fixing portion in the hollow fiber membrane module of FIGS. 1 and 2;

[Explanation of symbols]

 3 Open end face of hollow fiber membrane 5 Hollow fiber membrane knitted fabric 6 Housing and water collecting pipe 7 Fixing member 8 Water guiding pipe 9 Filtrate outlet

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naoya Tanakamaru 6-41 Konan, Minato-ku, Tokyo Inside Mitsubishi Rayon Co., Ltd. (72) Inventor Masumi Kobayashi 4--60 No. Mitsubishi Rayon Co., Ltd. (72) Inventor Tatsuharu Okada 1-6-1 Konan, Minato-ku, Tokyo Mitsubishi Rayon Engineering Co., Ltd.

Claims (5)

[Claims] 1. A hollow fiber membrane module in which one end or both ends of a sheet-like hollow fiber membrane is fixed by a fixing member in a housing while maintaining an open state of the hollow fiber membrane. A hollow fiber membrane module, wherein the length direction of the hollow fiber membrane of the hollow fiber membrane module is arranged to be vertical. 2. The hollow fiber membrane module according to claim 1, wherein a plurality of sheet-like hollow fiber membranes are arranged, and the fixing member is fixed to the water collecting pipe. 3. A hollow fiber membrane module unit, wherein a plurality of the hollow fiber membrane modules according to claim 1 or 2 are arranged in parallel or stacked. 4. A hollow fiber membrane module unit in which a plurality of the hollow fiber membrane modules according to claim 1 or 2 are arranged in parallel, and wherein the first is arranged adjacent to each other. Of the hollow fiber membrane module and the second hollow fiber membrane module of the first hollow fiber membrane module, the sheet-like hollow fiber membrane that is arranged on the side closest to the second hollow fiber membrane module among the sheet-like hollow fiber membranes Between the hollow fiber membrane forming the first hollow fiber membrane module and the sheet-shaped hollow fiber membrane disposed closest to the first hollow fiber membrane module among the sheet-shaped hollow fiber membranes in the second hollow fiber membrane module. A hollow fiber membrane module unit having a distance of 5 to 100 mm. 5. A hollow fiber membrane module unit provided with a diffuser tube, wherein a diffuser tube is integrally provided with the hollow fiber membrane module unit according to claim 3 or 4.