JP3929194B2 - Hollow fiber membrane unit and membrane separator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hollow fiber membrane unit and a membrane separation device used for solid-liquid separation by being installed in a sewage water treatment facility such as purified water, sewage, human waste, and various types of waste water.
[0002]
[Prior art]
In sewage treatment, it is widely practiced to separate and remove solids of a certain particle size from sewage by membrane separation of sewage, and to reuse the treated water. As one of the apparatuses, a membrane separation apparatus using a hollow fiber membrane unit obtained by unitizing hollow fiber membranes is known.
[0003]
Here, the hollow fiber membrane has, for example, a diameter of about 0.1 to 0.4 μm, for example, on the peripheral wall of a hollow fiber having an outer diameter of about 1000 μm, for example, EVAL, ethylene vinyl alcohol, or polyethylene resin. In order to separate the solid and liquid by allowing only the treated water excluding solids to permeate into the interior by sucking the inside and making it into a low pressure state while being immersed in the sewage. It has become.
[0004]
This type of membrane separation device is required not only to have a large filtration (separation) area and excellent water permeability, but also to prevent clogging and maintain the permeation flow rate. ing. For this reason, for example, a submerged water treatment apparatus has been proposed in which hollow fiber membranes are arranged in a planar manner like a blind and unitized, and these are continuously arranged in a tank.
[0005]
[Problems to be solved by the invention]
However, in the conventional technology, for example, when collecting the water collecting portions installed on both sides of the hollow fiber membrane and collecting the treated water that has permeated the hollow fiber membrane in the water collecting portion, the length of the water collecting portion When the length is long, the peripheral wall of the water collecting portion may be recessed due to the suction force (negative pressure) acting on the water collecting portion. And if a water collection part is dented in this way, treated water will not flow smoothly inside this, but maintenance of a permeation flow velocity will become difficult. In particular, in the upper part of the water collecting part, a large amount of treated water flows here, so this disadvantage becomes remarkable. In addition, for example, it is not possible to replace only a portion that may be clogged or damaged and leak, and there is a problem in maintainability.
[0006]
The present invention has been made in view of the above circumstances, and even if the length of the water collecting portion for collecting the treated water that has permeated through the hollow fiber membrane is increased, deformation of the water collecting portion can be prevented. An object of the present invention is to provide a hollow fiber membrane unit and a membrane separation device excellent in maintainability.
[0007]
[Means for Solving the Problems]
In the hollow fiber membrane unit of the present invention, a plurality of hollow fiber membranes are sparsely arranged with a predetermined distance between a pair of rectangular water collecting discs, and both ends of the hollow fiber membranes are opened on the surface of the water collecting disc. The hollow fiber membrane module is configured, and the water collection housing is formed of a web portion and flange portions at both ends, and is arranged so that the water collection plate of the hollow fiber membrane module is fitted into the opening, and the water collection plate A water collecting channel is formed between the water collecting housing and the water collecting housing, and the water collecting plate of the hollow fiber membrane module is mounted in a plurality of layers in the water collecting housing, and the water collecting plate is mounted in a stacked manner. A spacer is interposed between the flanges, and concave portions are provided at the flange portions at both ends of the water collecting housing, and convex portions are provided at both ends of the spacer, and the convex portions are fitted into the concave portions, thereby Wear watertight, inside The fiber membrane module characterized by being stacked in multiple stages.
[0008]
Thus, a plurality of hollow fiber membrane modules each formed separately are stacked in multiple stages to form a hollow fiber membrane unit having a predetermined height, thereby facilitating maintenance of the hollow fiber membrane unit and collecting water. The water collecting housing can be reinforced at predetermined intervals along its length by spacers interposed between the water collecting boards mounted in the housing, and deformation of the water collecting housing can be prevented. In addition, since the sludge easily collects in the portion when the hollow fibers are tightly bundled in the water collecting portion as in the prior art, the hollow fiber membrane is sparsely disposed in the present invention. For this reason, since there is a concern about deformation in the water collecting housing, it is configured as described above.
[0009]
The water collecting housing is provided with a plurality of reinforcing ribs extending along the length direction on the inner peripheral surface of the web portion, and the spacer has a protrusion whose tip abuts on the inner peripheral surface of the web portion. A portion is formed. Thereby, the water collection housing itself can be reinforced by the reinforcing ribs, and the web portion of the water collection housing can be supported by the protrusions of the spacers. Here, the water collecting housing is preferably U-shaped in cross section, but may have other shapes, for example, a semicircular shape.
[0010]
Further, the water collecting housing is characterized in that holding portions for holding the flange portions of the water collecting housing from the front-rear direction are provided at both ends of the spacer. Thereby, it can prevent deform | transforming so that the front-end | tip may spread by clamping the flange part of a water collection housing from the front-back direction with a clamping part. Here, the water collecting housing is preferably U-shaped in cross section, but may have other shapes, for example, a semicircular shape.
[0011]
The membrane separator of the present invention is characterized in that a treated water take-out pipe connected to a suction device is connected to the end of the water collecting housing of the hollow fiber membrane unit according to claims 1 to 4. Thereby, a deformation | transformation of a water collection housing can be prevented and the permeation | transmission flow rate of a membrane separator can always be maintained constant.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 3 show the overall configuration of a hollow fiber membrane unit and a membrane separation apparatus including the unit according to an embodiment of the present invention. Each of the membrane separation apparatuses includes four hollow fiber membrane modules 10. Two sets of hollow fiber membrane units 20 having the above and below are provided.
[0013]
In the hollow fiber membrane module 10, a plurality of hollow fiber membranes 12 are sparsely arranged between a pair of rectangular water collecting plates 11, 11 while being spaced apart from each other at a predetermined interval in the vertical and front-rear directions at a pitch of 2.2 mm, for example. Configured. Each of the hollow fiber membranes 12 extends through the inside of the water collection board 11 and opens at the board surface of the water collection board 11 (see FIG. 4). The water collecting board 11 is made of, for example, a hard potting portion 13 made of a thermoplastic resin, and made of, for example, silicon rubber or soft plastic (polyvinyl chloride, polystyrene, polyurethane). And a soft potting portion 14 acting as a convex portion 15 is formed on both front and rear end faces.
[0014]
For example, the hollow fiber membrane module 10 is formed by bundling a single hollow fiber membrane a predetermined number of times, shaping the hollow fiber membrane into a predetermined shape, potting a resin material at both ends, and positioning the hollow fiber membrane outside the potting portion after solidification. The U-shaped hollow fiber membrane is cut and removed.
[0015]
The hollow fiber membrane unit 20 is provided with a pair of water collection housings 21 extending linearly to absorb water from the water collection boards 11 at both ends of each hollow fiber membrane module 10 by the suction device 55. The water collecting housing 21 is made of a resin such as vinyl chloride or ABC resin, and is formed in a U-shaped cross section from the web portion 22 and the flange portions 23 at both ends, as shown in FIG. 11 is arranged to fit. On the inner peripheral surface of the web portion 22, a plurality of (three in the figure) reinforcing ribs 24 are provided over the entire length in the length direction, and the convex portions 15 of the water collecting panel 11 are provided on both flange portions 23. And a recess 25 to be fitted.
[0016]
The two water collecting plates 11 of the first-stage hollow fiber membrane module 10 are placed in the pair of water collecting housings 21, and the second and further both water collecting plates 11 of the third-stage hollow fiber membrane module 10 are placed thereon. By sequentially mounting, in this example, a hollow fiber membrane unit 20 having four (four stages) hollow fiber membrane modules 10 is configured. Here, the convex portion 15 of the water collecting plate 11 is fitted into the concave portion 25 of the water collecting housing 21, and the opening portion of the water collecting housing 21 is watertightly closed by the water collecting plate 11. A treated water collecting channel 26 extending in the vertical direction is defined between the water housing 21 and the water housing 21. Note that the water collecting board 11 and the water collecting housing 21 may be bonded with an adhesive, or another sealing means may be provided.
[0017]
Further, in the water collection housing 21, the first and second stages, and the third and fourth stages of the hollow fiber membrane modules 10 and 10, between the two collection boards 11 and 11 positioned above and below the first and second stages. A first spacer 27 is interposed, and a second spacer 28 is interposed between the two water collecting plates 11 and 11 located above and below the second-stage and third-stage hollow fiber membrane modules 10 and 10.
[0018]
The first spacer 27 is formed of a plate having a thickness of about 5 mm, for example, and as shown in FIG. 5, the planar shape is formed so as to be substantially the same as the cross-sectional shape of the water collecting board 11, Convex portions 29 that fit into the concave portions 25 of the water collecting housing 21 are provided at both front and rear ends. Thereby, the watertightness here is ensured by making the convex part 29 of the 1st spacer 27 fit in the recessed part 25 of the water collection housing 21. Here, the water collecting housing 21 is provided with reinforcing ribs 24 so that deformation is unlikely to occur. Further, a pair of protrusions 30 whose tips surround the reinforcing rib 24 of the water collecting housing 21 and abut against the inner peripheral surface of the web portion 22 are provided on the outer surface of the first spacer 27. The first spacer 27 mainly supports the web portion 22 of the water collecting housing 21 by a part along the length direction thereof, and acts so as not to be recessed. In addition, by providing the pair of protrusions 30, a water flow part 31 through which treated water flows inside the first spacer 27 is formed.
[0019]
On the other hand, the second spacer 28 is formed of, for example, a plate having a thickness of about 5 mm, and is formed so that the planar shape thereof is substantially the same as the cross-sectional shape of the water collecting board 11 as shown in FIG. At both the front and rear ends, convex portions 32 that fit into the concave portions 25 of the water collecting housing 21 are provided. Thereby, the watertightness here is ensured by fitting the convex part 32 of the 2nd spacer 28 in the recessed part 25 of the water collection housing 21. Further, a holding piece 33 extending to the side of the front and rear end faces is provided, and a holding section 34 is provided for holding each flange portion 23 of the water collecting housing 21 from the front and rear directions between the end face and the holding piece 33. Has been. The second spacer 28 mainly holds each flange portion 23 of the water collection housing 21 from the front and rear by a holding portion 33 at a part along the length direction of the water collection housing 21. The tip is deformed so as to expand and acts to prevent the watertightness from being destroyed.
[0020]
Each water collection housing 21 of each hollow fiber membrane unit 20 is connected up and down via a connector 40 (see FIG. 1). Inside the connector 40, as shown in FIG. 7, a water passage hole 41 penetrating vertically is provided. As a result, the water collecting channels 26 of the hollow fiber membrane units 20 communicate with each other. In addition, as shown in FIG. 8, a recessed portion 42 is formed along the shape of the water collecting housing 21 at both upper and lower end faces of the connector 40, and the end portion of the water collecting housing 21 is inserted into the recessed portion 42. By being inserted, it can be easily connected while ensuring watertightness.
[0021]
Further, end caps 50 are attached to the lower ends of the water collecting housings 21 of the hollow fiber membrane unit 20 located below and the upper ends of the water collecting housings 21 of the hollow fiber membrane unit 20 located above. A pair of connecting rods 51 are spanned between the connectors 40, 40 facing each other and between the end caps 50, 50 (see FIG. 3). A connecting rod may be provided between the spacers.
[0022]
Furthermore, as shown in FIG. 1, the end cap 50 attached to the lower end of each water collecting housing 21 of the hollow fiber membrane unit 20 positioned below is closed by a plug member 52. On the other hand, the end cap 50 attached to the upper end of each water collecting housing 21 of the hollow fiber membrane unit 20 positioned above is connected with a treated water discharge pipe 54 branched in two directions via a connecting nut 53, respectively. A suction device 55 such as a water absorption pump is connected to the treated water take-out pipe 54.
[0023]
Next, usage examples of the membrane separation device will be described.
First, the hollow fiber membrane unit 20 is installed, for example, in an aeration tank in which an air diffusing pipe for jetting air is disposed below, and is immersed in sewage in the aeration tank, and air is jetted from the diffusing pipe. Then, each hollow fiber membrane 12 is sucked from the water collecting passage 26 inside the water collecting housing 21 by the suction device 55 to perform solid-liquid separation of the sewage, and the treated water is taken out from the treated water take-out pipe 54 to the outside. At this time, the treated water that has passed through each hollow fiber membrane 12 flows through the water collection channel 26 and flows into the treated water take-out pipe 54.
[0024]
Here, the inside of the water collection channel 26 becomes negative pressure with the suction of the suction device 55, and a considerably large external pressure acts on the water collection housing 21. The water collection housing 21 has a predetermined length along its length direction. Reinforced by spacers 27 and 28 interposed between the water collecting plates 11 and 11 mounted in the water collecting housing 21 at intervals, so that even if the length of the water collecting housing 21 is increased, this deformation is prevented. Is prevented. Accordingly, the treated water always flows smoothly through the water collecting passage 26 inside the water collecting housing 21 to maintain the permeation flow rate of the membrane separation device.
[0025]
In addition, the air ejected from the air diffuser at this time is formed between the hollow fiber membrane modules 10 and 10 by the spacers 27 and 28, for example, with an interval of 7.2 mm (spacer thickness 5 mm and hollow fiber membrane pitch). 2.2 mm in total)) and reach the inner side in the width direction of the hollow fiber membrane module 10. As a result, the separation (filtration) area substantially increases. In particular, at the upper part of the hollow fiber membrane unit, it is possible to efficiently remove air and sludge adhering to the hollow fiber membrane by a water flow by air.
[0026]
In addition, a plurality of hollow fiber membrane modules 10 each formed separately are stacked in multiple stages to form a hollow fiber membrane unit 20 having a predetermined height, for example, some of the hollow fiber membranes 12 are clogged or the like. When a defect occurs, this can be dealt with quickly by replacing the hollow fiber membrane module 10 having the hollow fiber membrane 12 with the defect.
[0027]
In the above-described embodiment, an example in which spacers having the same wall thickness are used is shown. However, for example, spacers having different wall thicknesses are used. Alternatively, the spacer may be formed of a tubular body.
[0028]
Moreover, in the said embodiment, although the example which alternately arrange | positions the 1st spacer and 2nd spacer from which a shape differs was demonstrated, you may make it use only the spacer of one shape. In addition, the spacer may have a shape in which the protrusion of the first spacer and the sandwiching portion of the second spacer are held together. Thus, various modified embodiments are possible without departing from the spirit of the present invention.
[0029]
【The invention's effect】
As described above, according to the present invention, even if the length of the water collecting portion (water collecting housing) for collecting the treated water that has permeated through the hollow fiber membrane is increased, the water collection is performed by interposing the spacer. The permeation speed can be maintained by preventing the deformation of the portion and allowing the treated water to flow smoothly through the inside. Moreover, even if a defect occurs in some of the hollow fiber membranes, this can be dealt with quickly by replacing the hollow fiber membrane module.
[Brief description of the drawings]
FIG. 1 is a front view showing a hollow fiber membrane unit according to an embodiment of the present invention and a membrane separation apparatus including the unit.
FIG. 2 is a right side view of FIG.
3 is a plan view of FIG. 1. FIG.
4 is an enlarged sectional view taken along line A in FIG.
5 is an enlarged sectional view taken along line B of FIG.
6 is an enlarged sectional view taken along line C of FIG.
7 is an enlarged sectional view taken along line D of FIG.
8 is an enlarged sectional view taken along line EE of FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Hollow fiber membrane module 11 Water collecting board 12 Hollow fiber membrane 20 Hollow fiber membrane unit 21 Water collecting housing 22 Web part 23 Flange part 24 Reinforcing rib 26 Water collecting channel 27, 28 Spacer 30 Protrusion part 33 Holding piece 34 Holding part 40 Connector 50 End cap 54 Treated water take-out pipe 55 Suction device

Claims (5)

A hollow fiber membrane module is configured in which a plurality of hollow fiber membranes are arranged sparsely between a pair of rectangular water collecting discs while being spaced apart from each other by a predetermined distance, and both ends of the hollow fiber membranes are opened on the surface of the water collecting disc. ,
The water collecting housing is formed from a web portion and flange portions at both ends, and is disposed so that the water collecting plate of the hollow fiber membrane module is fitted into the opening, and treated water is disposed between the water collecting plate and the water collecting housing. The waterway is divided and formed
A plurality of stacked water collecting panels of the hollow fiber membrane module are mounted in the water collecting housing, and a spacer is interposed between the stacked water collecting disks ,
The flange portions at both ends of the water collecting housing are provided with recesses, and the both ends of the spacer are provided with protrusions, and by fitting the protrusions into the recesses, the spacers are mounted in a watertight manner, A hollow fiber membrane unit comprising hollow fiber membrane modules stacked in multiple stages.   The water collecting housing is provided with a plurality of reinforcing ribs extending along the length direction on the inner peripheral surface of the web portion, and the spacer has a protruding portion whose tip abuts on the inner peripheral surface of the web portion. The hollow fiber membrane unit according to claim 1, wherein the hollow fiber membrane unit is formed.   2. The hollow fiber membrane unit according to claim 1, wherein the water collecting housing is provided with a clamping portion that clamps each flange portion of the water collecting housing from the front-rear direction at both ends of the spacer.   The hollow fiber membrane unit according to claim 2 or 3, wherein the water collection housing has a U-shaped cross section.   5. A membrane separation apparatus, wherein a treated water take-out pipe connected to a suction device is connected to an end of a water collecting housing of the hollow fiber membrane unit according to claim 1.

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