JPH04330920A - Membrane separator - Google Patents

Abstract

PURPOSE:To improve the treating efficiency of a membrane separator. CONSTITUTION:A permeated water passage is formed between the corrugated separation membranes 21 and 21 with a corrugated spacer 23 in between. A flat spacer is interposed between the flat separation membranes 22 and 22 to form a permeated water passage. The corrugated separation member 21 and the flat separation membrane 22 are arranged in direct contact with each other to form a raw water passage between the membranes. As a result, a raw water passage forming spacer is not needed, the membrane area per unit volume in the separator is increased, the resistance to the raw water is not increased, and the amt. of water permeated is increased.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to membrane separation devices such as reverse osmosis membrane separation devices, ultrafiltration devices, precision filtration devices, etc., and in particular membrane separation using a wavy separation membrane as a part of the separation membrane. It is related to the device.

0002

[Prior Art] Membrane separation devices such as reverse osmosis membrane separation devices include
There are spiral-type membrane separators in which separation membranes are wound around the outer periphery of a water collection pipe and stacked in a spiral shape, and flat membrane-type membrane separators in which flat plate-shaped separation membranes are stacked. Both membrane separation devices have a structure in which multiple separation membranes are stacked and a raw water flow path is provided on one membrane side of each separation membrane, and a permeated water flow path is provided on the other membrane side. There is. Note that between the separation membranes, spacers for forming raw water channels and spacers for forming permeated water channels are alternately arranged for each separation membrane.

Next, a conventional spiral type membrane separation apparatus will be explained with reference to FIGS. 5 to 7.

FIG. 7 is a cross-sectional view taken in a direction perpendicular to the axial direction of a water collection pipe of a spiral-type membrane module, and FIGS. 5 and 6 are a cross-sectional view and a perspective view showing an assembled structure of the spiral-type membrane module.

Reference numeral 11 denotes a water collection pipe, around the outer periphery of which a separation membrane 13 is wound with a corrugated spacer (corrugate spacer) 12 in between. As shown enlarged in Figure 5,
The water collection pipe 11 has an opening 11a that communicates between the inside and outside of the pipe. The separation membrane 13 is in the form of a sheet, and the central part 13a of the sheet wraps around the water collection pipe 11, and the non-central part 13
b and 13c are wound around the water collection pipe 11 in an overlapping state.

[0006] Furthermore, a water collecting cloth (mesh spacer) 14 is inserted inside the sheet-like separation membrane 13. The inside of this separation membrane 13 becomes a permeate flow path. The spacer 12 has a corrugated plate shape and extends continuously as shown in FIG.

As shown in FIGS. 5 and 6, in order to manufacture a spiral type membrane module, a mesh spacer 14 is sandwiched between non-center portions (hereinafter simply referred to as separation membranes) 13b and 13c of the separation membrane, and a laminated structure is formed. A sheet 15 is formed, and the laminated sheet 15 and the corrugated spacer 12 are wrapped around the outer periphery of the water collection pipe 11 in a superimposed state. At the time of winding, adhesive 16 is applied to the side portions of the separation membranes 13b and 13c, and the side sides of the separation membranes 13b and 13c are bonded together by the overlapping pressure during winding. When the sides of the separation membranes 13b and 13c are bonded together in this manner, the separation membrane 13 becomes bag-shaped as a whole, and a structure is created in which the raw water flow path and the permeated water flow path 17 within the separation membrane 13 are isolated.

[0008]

[Problems to be Solved by the Invention] As mentioned above, in conventional membrane separation devices, a raw water flow path is formed on one membrane side of a separation membrane, and a permeated water flow path is formed on the other membrane side. In addition, it is necessary to arrange spacers for forming raw water channels and spacers for forming permeated water channels on both sides of one separation membrane.

[0009] In such a configuration, the amount of spacers in the membrane separator increases, and the amount of separation membranes per unit volume (membrane area) in the membrane separator decreases. Furthermore, the spacer creates a large flow resistance within the raw water flow path, causing energy loss of the raw water and significantly lowering the energy efficiency of separation.

0010

[Means for Solving the Problems] The membrane separation device of the present invention includes:
In a membrane separation device in which a plurality of separation membranes are stacked, a raw water flow path is provided on one membrane side of each separation membrane, and a permeated water flow path is provided on the other membrane side, a flat separation membrane, A wavy separation membrane is laminated, and the raw water flow path is formed between the wavy separation membrane and the flat separation membrane.

[0011]

[Operation] In the membrane separation device of the present invention, a flat separation membrane and a wavy separation membrane are stacked, and the raw water flow path is formed between the flat separation membrane and the wavy separation membrane. A raw water flow path can be formed without intervening a spacer. That is, in the present invention, a spacer for forming a raw water flow path is not necessary. As a result, the amount of separation membranes can be increased in accordance with the amount of the omitted spacer for the raw water flow path. In addition, since all contact surfaces of raw water in the membrane separation device are membrane surfaces, energy loss of raw water due to flow path resistance of the spacer is eliminated, and processing energy efficiency is improved.

0012

Embodiments Hereinafter, embodiments will be described with reference to the drawings. FIG. 1 is a sectional view showing an example of manufacturing a membrane module of a spiral type membrane separation apparatus according to an embodiment, and FIG. 2 is a sectional view of a main part of the same membrane module.

In this embodiment, the separation membrane 20 wound around the outer periphery of the water collection pipe 11 has a corrugated portion 21 and a flat portion 22 . A wavy water collection spacer 23 is interposed between the pair of wavy portions 21 , 21 , and a flat water collection spacer 24 is interposed between the pair of flat portions 22 .

Permeated water channels 25 and 28 are formed between the pair of wavy portions 21 and 21 and between the pair of flat portions 22 and 22, and communicate with the inside of the water collection pipe 11. In addition, as before,
The peripheral edges of each wavy portion 21, 21 are joined, and each flat portion 2
The peripheral edges of 2 and 22 are also joined, and the permeated water flow path is isolated from the outside.

Each wavy portion 21 and flat portion 22 are connected to the water collection pipe 1.
1, a membrane module 26 having the channel configuration shown in FIG. 2 is constructed. In this membrane module 26, a raw water flow path 27 is formed between the corrugated portion 21 and the flat portion 22. The crest of the wave of the wavy portion 21 is in direct contact with the flat portion 22, and no spacer for forming a raw water flow path is inserted into this raw water flow path 27.

This membrane module 26 is packed into a cylindrical pressure-resistant container, and raw water is allowed to flow into the raw water channel 27 of the membrane module 26 from one end surface of the membrane module 26 . A membrane separation process is performed while the raw water passes through the raw water channel 27, and the water that has passed through the separation membrane 20 flows into the permeated water channels 25 and 28. This permeated water flows into the water collecting pipe 11 from the permeated water channels 25 and 28, and is taken out from the water collecting pipe 11 to the outside of the membrane separation apparatus. The concentrated water that has passed through the raw water channel 27 is discharged to the outside of the membrane separation apparatus from the concentrated water chamber between the opposite end surface of the membrane module 26 and the end surface of the pressure vessel.

[0017] As described above, in the membrane separation apparatus of this example,
A spacer for configuring the raw water flow path is not required, and the amount of separation membrane per unit volume in the membrane separation device can be increased, and the membrane area can be increased. Therefore, the amount of permeated water can be increased. Of course, even if the membrane area of the separation membrane increases, since there is no spacer for forming a raw water flow path, the water flow resistance of the raw water will not increase at all or hardly.

FIGS. 3 and 4 are cross-sectional views showing another embodiment. The present embodiment is a flat membrane type membrane separator, in which a rectangular pressure vessel 29 is filled with flat membrane modules 30. In this membrane module 30, a flat plate-shaped wavy separation membrane 31 and a flat plate-shaped separation membrane 32 are laminated. As shown in FIG. 4, a water collection spacer 33 for forming a wavy permeate flow path is interposed between a pair of wavy separation membranes 31, 31, and a flat permeate spacer 33 is interposed between a pair of flat separation membranes 32, 32. A water collection spacer 34 for forming a water flow path is interposed. A raw water flow path 35 is formed between the pair of wavy separation membranes 31, 31 and the pair of flat separation membranes 32, 32.

By joining the peripheral edges of the pair of wavy separation membranes 31, 31, the permeated water flow path 36 between them is isolated from the raw water flow path 35, and the peripheral edges of the flat separation membranes 32, 32 are separated. By being joined, the permeate flow path 37 between the two
is isolated from the raw water flow path 35. Permeated water channel 36,
Permeated water is taken out from 37 via a permeated water tube 38.

In this embodiment as well, the crests of the waves of the wavy separation membrane 31 and the flat separation membrane 32 are in direct contact with each other, and a spacer for forming a raw water flow path is interposed in the raw water flow path 35 between them. It has not been. This embodiment also provides the same effects as those of the above embodiment.

In the present invention, in order to manufacture a pair of wavy separation membranes with wavy spacers interposed therebetween, for example, adhesive is applied to both sides of the wavy spacers, a bag-shaped separation membrane is covered, and then the bag is It is sufficient to reduce the pressure inside the spacer and bring the separation membrane into close contact with both sides of the wavy spacer. In this case, a mesh spacer may be present on the surface of the wavy spacer.

[0022] Another manufacturing method is to form a film directly on the spacer surface by immersing the wavy spacer in a film-forming solution or by spraying a dope solution onto the spacer surface and then gelling it. This method is particularly suitable for manufacturing flat membrane modules.

[0023]

[Effects of the Invention] As described above, the membrane separation device of the present invention stacks a flat separation membrane and a wavy separation membrane to form a raw water flow path directly between them, eliminating the need for a spacer for forming the raw water flow path. That is. Therefore, according to the present invention, (1) the membrane area per unit volume in the membrane separation device increases, and the flow rate of permeated water increases; ■ There is no water flow resistance between the spacer for forming the raw water flow path and the raw water flow path, reducing energy loss. Therefore, the amount of treated water can be increased without increasing energy consumption. ■ It is possible to reduce the volume of membrane separation equipment. Effects such as this are achieved.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing a method for manufacturing a membrane module of a membrane separation device according to an example.

FIG. 2 is a sectional view of a main part of a membrane module of a membrane separation device according to an example.

FIG. 3 is a sectional view of a membrane separation device according to another example.

FIG. 4 is an enlarged sectional view of a main part of a membrane module of a membrane separation device according to another embodiment.

FIG. 5 is a cross-sectional view showing a conventional method for manufacturing a spiral-wound membrane module.

FIG. 6 is a perspective view showing a conventional method for manufacturing a spiral membrane module.

FIG. 7 is a cross-sectional view of a conventional spiral-wound membrane module.

[Explanation of symbols]

11 Water collection pipe 20 Separation membrane 21 Wavy part 22 Flat part 23 Wavy water collection spacer 24 Flat water collection spacer 25 Permeated water flow path 26 Membrane module 27 Raw water flow path 28 Permeated water channel 29 Pressure-resistant container 30 Flat membrane type membrane module 31 Wavy separation membrane 32 Flat separation membrane 33 Wavy water collection spacer 34 Flat water collection spacer 35 Raw water flow path 36 Permeated water flow path 37 Permeated water flow path

Claims (1)

[Claims] Claim 1: A membrane separation device in which a plurality of separation membranes are stacked, a raw water flow path is provided on one membrane surface side of each separation membrane, and a permeated water flow path is provided on the other membrane surface side. A membrane separation device characterized in that a separation membrane and a wavy separation membrane are stacked, and the raw water flow path is formed between the wavy separation membrane and the flat separation membrane.