JPH08155278A - Production of membrane element - Google Patents

Abstract

PURPOSE: To easily produce a membrane element by boring a filtrate gathering hole in a bag-shaped membrane member and arranging a spacer ring to the gap between a membrane and a filtrate passage member in the periphery of the filtrate gathering hole of the bag-shaped membrane member and laminating a plurality of the bag-shaped membrane members to fasten them. CONSTITUTION: A filtrate gathering hole 13 is bored in a bag-shaped membrane member 1 having a filtrate passage member 11 housed therein and a flexible sheet like spacer ring 2 is inserted in the gaps between respective membranes 12 and the filtrate passage member 11 from the hole 13 in a bent state and the inserted spacer ring 2 is returned to the original planar state to be arranged around the hole 13. A plurality of the bag-shaped membrane members 1 thus constituted are laminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a membrane element of a membrane separation device used for filtering a stock solution.

[0002]

2. Description of the Related Art A laminated membrane element is known as a membrane element of a membrane separation device used for filtering a stock solution. For example, a filtrate liquid collecting hole is opened at a predetermined position of a bag-shaped membrane member containing a filtrate liquid flow path member, for example, a plastic net, and each membrane and the filtrate liquid flow around the filtrate liquid collecting hole. A spacer ring is arranged between the flow path member and a plurality of bag-shaped membrane members which are laminated so as to connect the filtrate liquid collecting holes, and the laminated body is clamped to connect the filtrate liquid collecting holes. Laminated membrane elements having a filtrate collecting water port are known, and spacers prevent the membrane from digging into the plastic net, which is a member for the filtrate flow passage, by the clamping force of the laminate, and a bag. The communication of the filtrate flow path in the membrane member to the water collecting port is ensured.

In this membrane element, the inner side of the bag-shaped membrane member is the filtrate side, and is subjected to the transmembrane pressure difference (for example,
(Decompression on the filtrate flow channel side), the filtrate that has permeated the membrane is taken out through the filtrate flow channel of the bag-shaped membrane member and the water collecting pipe.

[0004]

Conventionally, a hard plastic injection-molded product has been used for spacering of the above-mentioned membrane element, and its outer diameter is larger than that of the bag-like membrane member for collecting filtrate. In the production of the membrane element, a spacer ring is inserted between the membrane and the filtered liquid flow path member before sealing the periphery of the bag-shaped membrane member, and then the periphery of the membrane is closed. Is sealed, and the spacer ring is moved to the position of the filtrate water collecting hole of the bag-shaped membrane member to be placed at a predetermined site.

However, it is not easy for the spacer to move the bag-shaped membrane member to the filtered water collecting hole position, the membrane is an obstacle, the workability is poor, and the spacer is not moved during the movement.
There is a concern that the film may be damaged due to the saling being caught on the film.

An object of the present invention is to open a filtrate collecting hole in the bag-shaped membrane member and to provide a space between each membrane and the filtrate channel member around the filtrate collecting hole of the bag-shaped membrane member. -To provide a method capable of easily manufacturing a membrane element in which a plurality of bag-shaped membrane members are laminated and tightened after arranging saling.

[0007]

According to the method of manufacturing a membrane element according to the present invention, a bag for collecting filtrate 13 is opened in a bag-shaped membrane member 1 in which a member 11 for a filtrate channel is housed. Thirteen
The flexible sheet-shaped spacer ring 2 is bent and inserted between each membrane 12 and the filtered liquid flow path member 11, and the inserted spacer ring is returned to its original flat shape to form the above-mentioned holes. The bag-shaped film member 1 is arranged around the bag 13, and the bag-shaped film member 1 is laminated.

[0008]

Since a flexible sheet-shaped spacer ring 2 is used, the filtrate of the bag-shaped membrane member 1 is placed in the bag-shaped membrane member 1 with the spacer ring 2 folded. Water collection hole 1
The insertion spacer ring 2 can be returned to the original flat state and placed at a predetermined position (portion around the filtrate water collecting hole in the bag-shaped membrane member). Therefore,
After insertion, it is not necessary to move the spacer to the filtration liquid collecting hole position of the bag-shaped membrane member, and it is possible to eliminate the poor workability of this movement and the disadvantage of membrane damage caused by the spacer ring on the membrane. .

[0009]

Embodiments of the present invention will be described below with reference to the drawings. -(C) of FIG. 1 shows an example of a membrane element to be assembled according to the present invention. In FIG. 1C, reference numeral 1 is a bag-shaped membrane member, and a semipermeable membrane 12 is provided on both sides of a filtered liquid flow path member (eg, plastic net, plastic nonwoven fabric, tricot cloth, etc.) 11.
(For example, a microfiltration membrane or ultrafiltration membrane of polysulfone, polyethersulfone, polyacrylonitrile, polyolefin, polyamide, etc.) is attached and the periphery is sealed by heat fusion or an adhesive. Reference numeral 13 denotes a filtrate collecting hole formed in the bag-shaped membrane member 1, and 2 denotes a flexible sheet arranged around the hole 13 between the membranes 12 and the filtrate channel member 11. A sheet-shaped spacer ring (see FIG. 2 for the sheet-shaped spacer ring 2). 3 is an annular rubber packing. 4 is a filtrate collecting pipe (perforated pipe),
The bag-shaped membrane member 1 and the rubber packing 3 are alternately inserted into the filtered liquid collecting pipe 4, the inserted laminated body is sandwiched by the end plates 5 and 5, and the laminated body is tightened by the nuts 6 and 6.

In the above, the sheet-shaped spacer ring 2
Is to prevent the membrane 12 from digging into the filtered liquid flow path member 11 such as a plastic net due to the compressive stress of the packing 3 (prevents the filtered liquid flow path member 11 from being blocked), and A normal communication between the filtered liquid flow path and the inside of the water collection pipe 4 is guaranteed, and the sheet-shaped spacer ring 2 has a thickness of 0.01 mm to 3 mm which is harder than the membrane 12 and easy to fold.
Flexible film, for example, resin impregnated cloth, plastic net with finer mesh than the filtered liquid flow path member 11 (2
0 to 1000 mesh) or the like can be used.

In the above, the sheet-shaped spacer ring 2
It is preferable that the outer dimension of the rubber packing is larger than that of the rubber packing 3. In the above, the outer shape of the bag-shaped membrane member 1 is usually a quadrangle, but it may be a circle or an ellipse. The shape of the sheet-shaped spacer ring 2 is usually circular, but it may be square or elliptical.

In order to manufacture the above-mentioned laminated membrane element according to the present invention, as shown in FIG. 1 (a), membranes 12 are attached to both sides of a member 11 for a filtered liquid flow path, and the periphery thereof is bonded with an adhesive. Alternatively, the bag-shaped membrane member 1 is manufactured by sealing by heat fusion, and then the filtrate water collecting hole 13 is opened at a predetermined position.

Next, the flexible sheet-shaped spacer ring 2 is bent to a size such that it can be inserted into the filtrate liquid collecting hole 13 and the bent sheet-shaped spacer ring is collected. Inserted between the membranes 12 and the filtered liquid flow path member 11 through the use holes 13, the insertion spacer ring is returned to its original flat state, and the spacer ring is inserted as shown in FIG. Two
And the centers of the filtrate collecting holes 13 are substantially aligned with each other so that each spacer ring 2 is provided between the membrane 12 and the filtrate channel member 11 around the filtrate collecting holes 13. Place it on the part. In this case, the inner circumference of the spacer ring 2 is slightly projected from the inner circumference of the filtrate water collecting hole 13, and the spacer rings 2 and 2 are locally bonded to each other by an adhesive at the protruding portion. It is preferable to temporarily fix the spacer spacers 2 and 2.

In this way, after the spacer ring has been arranged at the portion between each membrane and the filtrate liquid flow path member around the filtrate liquid collecting hole, it is shown in FIG. As described above, the bag-shaped membrane member 1 and the rubber packing 3 are alternately inserted into the water collecting pipe 4, and the laminated body is tightened by screwing the nuts 6 and 6 to the water collecting pipe 4 through the end plates 5 and 5. Then the production of the membrane element is completed.

FIGS. 3A to 3C show another embodiment of the present invention. In the same manner as described above, the spacer rings 2 and 2 are filtered as shown in FIG. 3A. The liquid collecting holes 13 are arranged around the liquid collecting holes 13 between the membranes 12 and the filtered liquid flow path member 11, and then, as shown in FIG.
The water collecting rings 41, 42 made of plastic are welded to each film surface, and the rings 41, 42 are fastened by fitting the protrusions 43 and the recesses 44, and further, as shown in FIG.
The bag-shaped membrane members 1, ... With a water collecting ring are laminated, and the water collecting rings 41, 42 are joined by welding or the like, thereby completing the production of the membrane element.

In the membrane element manufactured by the present invention, a flexible cleaning member (rough plastic net, roving cloth, mat, etc.) is arranged between the bag-shaped membrane members,
The upper end can be inserted into and supported by the water collecting pipe. With such a configuration, the bag-shaped membrane member and the flexible cleaning member come into contact with each other when being swirled by the flow of the stock solution, and the formation of the cake layer on the membrane surface can be effectively prevented.

The membrane element manufactured according to the present invention can be used in various types of membrane separators, and depending on the structure of the membrane separator, it can be stably placed in the liquid tank under the flow of the stock solution. Assembled on the body. FIG. 4 shows an example of a membrane separation device using a membrane element manufactured according to the present invention. In FIG. 4, reference numeral 71 denotes an open type liquid tank to be treated (usually provided with a cover for preventing drops), which can be constructed by casting concrete, for example.
Reference numeral 72 is a stock solution supply pipe, and 73 is a stock solution supply pump. A
Is a membrane element, in which the flexible cleaning member a is arranged between the bag-shaped membrane members 1 and 1, and the frames b and b are attached to both ends to enable the stationary placement. Water collecting pipe 4 at the upper end
And is supported through the horizontal axis c. 7
Reference numeral 4 denotes a filtrate take-out pipe communicating with the permeate collecting pipe 4 of the membrane element, and 75 denotes a decompression pump. The filtrate take-out pipe 74 and the decompression pump 75 are provided on the filtrate side of each bag-shaped membrane member 1. A depressurizing unit that generates a transmembrane pressure difference between the inside and the outside of each bag-shaped film member 1 by depressurizing is configured. Reference numeral 76 is an air diffusing tube (air diffusing holes are formed at predetermined intervals) disposed below the juxtaposed member of the membrane elements, 77 is an air feeding piping to the air diffusing tube, and 78 is a blower.

To process the stock solution with this membrane separator, the stock solution supply pump 73 is driven to supply the stock solution into the liquid tank 71 to be processed, the decompression pump 75 is driven, and the filtration side of each bag-shaped membrane member 1 is driven. The pressure is reduced to generate a transmembrane pressure difference necessary for filtration, the filtration is advanced under the transmembrane pressure difference, and the stock solution is continuously or intermittently supplied at a flow rate substantially equal to the filtration flow rate. The stock solution is processed while keeping the water level of the stock solution in the processing solution tank 71 substantially constant.

In parallel with this stock solution treatment, the blower 78 is driven intermittently or continuously to disperse air from the air diffuser 76 into the stock solution, and a gas-liquid mixed flow of the diffused air and the stock solution is formed into a bag. It is raised to the stock solution flow path gap between the membrane members 1, 1.

In this case, in the flexible cleaning member a,
Both upper and lower ends are supported, and the original narrow space between the flexible cleaning members a and a is sufficiently maintained even when the air is scrubbed by the air diffuser 76. On the other hand, since the lower end of the bag-shaped membrane member 1 is in a free state, the bag-shaped film member 1 tries to move vigorously for air scrubbing, but the space between the flexible cleaning members a and a is kept sufficiently narrow. Therefore, the bag-shaped membrane member 1 and the flexible cleaning member a are slidably in contact with each other without being bent upward, and the solid matter is effectively prevented from adhering to the membrane surface.

In particular, the flexible cleaning member a is provided with an appropriate degree of slack so that the space between the flexible cleaning members a and a is reduced to the bag-shaped film member 1.
If the flexible cleaning member 2 is agitated and vibrated by air-scrubbing while suppressing the bending upward, the sliding between the flexible cleaning member a and the bag-shaped membrane member 1 Can be performed more violently, and the adhesion of solid matter to the film surface can be prevented even more effectively.

In FIG. 4, the horizontal bar c may be omitted and the flexible cleaning member a may be supported by the air diffuser 76.

[0023]

According to the method of manufacturing a membrane element according to the present invention, each membrane and the filtrate flow passage around the filtrate collecting hole of the bag-shaped membrane member having the filtrate flow passage member inside. When a spacer ring is arranged in a portion between the member and the bag member, a plurality of such bag-shaped membrane members are laminated so that the filtrate water collecting holes are communicated with each other and tightened to produce a laminated membrane element, Since it is possible to insert a spacer ring from the filtrate collecting hole of the bag-shaped membrane member and place the spacer ring at a predetermined site, before sealing the periphery of the bag-shaped membrane member. Since it is not necessary to insert the spacer ring into the filter, it is not necessary to move the spacer ring to the filter liquid collecting hole position after inserting the spacer ring. It is possible to eliminate disadvantages such as membrane damage caused by being stuck on the It can be safely produced with good workability.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of the present invention in process order.

FIG. 2 is a plan view showing a sheet-shaped spacer ring used in the present invention.

FIG. 3 is an explanatory diagram showing another embodiment of the present invention in process order.

FIG. 4 is an explanatory view showing a membrane separation device using a membrane element manufactured according to the present invention.

[Explanation of symbols]

 1 Bag-shaped Membrane Member 11 Filtrate Liquid Channel Member 12 Membrane 13 Filtrate Liquid Collection Hole 2 Sheet-shaped Spacer 3 Packing 4 Permeate Collection Tube 41 Water Collection Ring 42 Water Collection Ring

Claims (1)

[Claims] 1. A bag-shaped membrane member, in which a member for a filtrate liquid channel is housed, is provided with a hole for collecting a filtrate liquid, and a flexible hole is provided between each membrane and the member for a filtrate liquid channel through the hole. A sheet-shaped spacer ring is bent and inserted, the inserted spacer ring is returned to its original planar shape, the sheet spacer is placed around the hole, and the bag-shaped membrane member is laminated. How to make.