JPS595004B2 - Hollow fiber membrane separation equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved membrane separation device having a pressure receiving plate adjacent to an opening surface of the hollow fiber in a membrane separation device equipped with a hollow fiber whose membrane wall has permselectivity for a fluid. .

Membrane separation methods that use selectively permeable membranes have recently attracted attention as a method for separating some components in a fluid.

Operations that apply membrane separation methods include reverse osmosis, ultrafiltration, dialysis, liquid permeation, and gas permeation.

Examples include bar vaporization and forward osmosis.

Conventionally, various types of membrane separation devices have been proposed, and the representative types are flat membrane type, tube type, spiral type, and hollow fiber type. Among these, the hollow fiber type has a device unit volume of light It has advantages such as a large membrane area, self-supporting properties, and no need for a membrane support, and is becoming popular.

However, this hollow fiber membrane separation device also has many drawbacks that should be improved.

In an example of a conventionally proposed hollow fiber membrane separation device, a hollow fiber assembly is housed in a cylindrical container, and each hollow fiber is stacked in many layers and extends in the axial direction of the hollow fiber assembly. The structure is such that it penetrates the resin wall located at the end and opens to the outside.

However, in a device with this structure, when attempting to promote separation by applying pressure to the fluid in contact with the outer surface of the hollow fiber, the resin wall deforms due to the pressure, causing damage to the bond between the hollow fiber and the resin wall. This has the disadvantage that fluid leaks and, in severe cases, the resin wall may be damaged.

In another example, a pressure-receiving plate having a large number of holes formed on the entire surface is provided adjacent to the resin wall in order to prevent the resin wall from deforming.

With this structure, the resin wall does not deform even when the fluid in contact with the outer surface of the hollow fiber is pressurized.

However, this structure has the drawback that the opening of the hollow fiber is blocked at a portion where the hole in the pressure receiving plate and the opening of the hollow fiber do not match, so that the fluid to be treated does not flow there, and the permeation capacity per unit volume of the device is reduced.

Further, as another example of the pressure receiving plate adjacent to the hollow fiber opening surface of the resin wall, a porous plate using a material made of sintered metal or sand hardened with resin has been proposed.

In the case of this pressure receiving plate, although the hollow fiber opening end is less likely to be blocked than in the above-mentioned example, the opening end is still considerably blocked, resulting in a decrease in membrane separation efficiency.

The present inventors have investigated a structure for a pressure receiving plate that overcomes the above-mentioned drawbacks of conventional devices, prevents deformation of the resin wall, and minimizes the reduction in effective membrane area, and has developed the present invention. Reached.

That is, the present invention is constructed of a cylindrical container and a columnar hollow fiber assembly housed in the cylindrical container, and the hollow fiber assembly is composed of a plurality of hollow fibers having selective permeability to fluid. It consists of a fiber layer and a resin wall located at at least one end of the hollow fiber layer, and the hollow fibers constituting the hollow fiber layer penetrate at least one of the resin walls and are open to the outside thereof, and the resin In a membrane separation device in which a pressure receiving plate is disposed adjacent to a hollow fiber opening surface of a wall, a linear protrusion is provided over the entire surface of at least one surface of the pressure receiving plate, and a straight protrusion is provided at the tip of the protrusion in contact with the hollow fiber opening surface. This membrane separation device is characterized by:

According to the membrane separator of the present invention, the deformation of the resin wall can be prevented by the pressure receiving plate, and since the contact area between the hollow fiber opening surface of the resin wall and the pressure receiving plate is small, the effect of blocking the hollow fiber opening is effective. The reduction in membrane area can be kept to a minimum.

Also, since the protrusions are linear, they have the advantage of being difficult to dig into the resin wall.

Furthermore, the shape of the pressure-receiving plate or the gap between the pressure-receiving plate and the opening surface of the hollow fiber is simple, and there is no stagnation in the flow of fluid leading inside the hollow fiber, which can prevent the fluid from deteriorating easily or containing microorganisms. It is highly effective when reproduction is a problem.

Further, since the shape of the pressure receiving plate is simple, there is also the effect that molding is easy.

The membrane separation apparatus of the present invention will first be described with reference to examples of drawings.

FIG. 1 is a sectional view showing an example of the membrane separation apparatus of the present invention.

In FIG. 1, 1 is a hollow fiber assembly, 2 is a cylindrical container housing the hollow fiber assembly 1, and 4 and 5 are end plates.

The hollow fiber assembly 1 includes a hollow fiber layer 6, a perforated tube 7, a resin wall 8,
It consists of 9.

The hollow fibers constituting the hollow fiber layer 6 are bundled and arranged in a U-shape, and the ends thereof penetrate the resin wall 8 and open outward.

A pressure receiving plate 3 is provided between the resin wall 8 and the end plate 4, and the pressure receiving plate 3 has a large number of linear protrusions, and the tips of the protrusions are in contact with the hollow fiber opening surface of the resin wall 8.

The end plate 4 is provided with a fluid inlet/outlet 10 connected to the inside of the hollow fiber,
It is supported by the cylindrical container 2 via a snap ring 13.

Further, the end plate 5 has a fluid inlet/outlet 11 communicating with the outer peripheral edge of the hollow fiber.
．． 12, and is supported by the cylinder 2 via a snap ring 14.

15, 16, 17, 18 are 01 for sealing fluid
This is J-ng.

When performing reverse osmosis using the membrane separator shown in FIG. The remaining treated fluid passes through the inside of the hollow fiber and is discharged from the fluid inlet/outlet 12 through the flow path between the hollow fiber layer 6 and the cylindrical container 2.

On the other hand, the fluid that has permeated inside the hollow fiber passes through the resin wall 8 through the inner flow path of the hollow fiber, and passes through the hollow fiber opening surface 1 of the resin wall 8.
9 to the end plate 4 through the flow path between the pressure receiving plate 3 and the resin wall 8.
The fluid is taken out from the fluid inlet/outlet 10 of the.

Since the fluid to be treated is forced into the hollow fiber layer under fairly high pressure, there is a risk that the resin walls 8 and 9 will deform under the pressure.

In particular, the resin wall 8 has a low strength because many hollow fibers penetrate through it, and requires special reinforcement, but it does not deform due to the action of the pressure receiving plate 3, and the contact area between the resin 8 and the pressure receiving plate 3 is small. Since it is small, it is less likely to block the hollow fiber opening.

FIG. 2 is a sectional view showing another specific example of the membrane separation device of the present invention.

The feature of this is that the pressure receiving plate also serves as an end plate, and the other features are the same as in the case of Fig. 1.

In FIG. 2, 21 is a hollow fiber assembly, 22 is a cylindrical container housing the hollow fiber assembly 21, 23 is a pressure receiving plate that also serves as an end plate, and 25 is an end plate.

The hollow fiber assembly 21 consists of a hollow fiber layer 26, a perforated tube 27, and a resin wall 28, 29. The hollow fibers constituting the hollow fiber layer 6 are bundled and arranged in a U-shape, and both ends of the hollow fibers are arranged in a U-shape. penetrates the resin wall 28 and opens to the outside.

30 is a permeated fluid outlet, 31 is a treated fluid inlet, and 32 is a treated fluid outlet.

In addition, in the example of the drawing, the hollow fiber is U-shaped, and its open end penetrates only the resin wall 8 or 28 on the left side.
It is also possible to have a structure in which the hollow fibers are arranged in a straight line, penetrate through the resin walls on both the left and right sides, and have open ends on the outside.

In that case, it is preferable to arrange pressure receiving plates outside the resin walls on both sides.

FIG. 3 is a plan view showing a specific example of the pressure receiving plate in the membrane separation device of the present invention, FIG. 4 is a cross-sectional view taken along line A-A in FIG. 3, and FIG. It is a sectional view cut along the BB line.

In FIGS. 3 and 4, the pressure receiving plate 40 has a large number of protrusions 41 arranged concentrically, and when the pressure receiving plate 40 is incorporated into a membrane separation device, the tips 42 of the protrusions 41 are connected to the hollow fibers of the resin wall. Linear contact with the opening surface.

Further, the pressure receiving plate 40 is provided with a fluid inlet/outlet 44 at the center thereof,
The fluid inlet/outlet 44 communicates with the groove 45 of the protrusion 41, and the fluid communicating with the inside of the hollow fiber flows in or out through the fluid inlet/outlet 44.

FIG. 6 is a plan view showing another specific example of the pressure receiving plate of the membrane separation apparatus of the present invention, and FIG. 7 is a sectional view of the pressure receiving plate of FIG. 6 taken along the line CC.

The pressure receiving plate 50 has a large number of protrusions 51 arranged in parallel lines, and when the pressure receiving plate 50 is incorporated into a membrane separation device, the tips 52 of the protrusions 51 are aligned with the hollow fiber opening surface of the resin wall. come into contact with

Further, the pressure receiving plate 50 has a hole 35 in the groove 54, and the hole 55 communicates with a groove 56 provided on the opposite side of the pressure receiving plate 50 from the surface where the protrusion 51 is located, and this groove 56 communicates with the fluid inlet/outlet.

In the pressure receiving plate of the present invention, the tip of the linear protrusion is in linear contact with the hollow fiber opening surface, and the line width of the tip of the linear protrusion is narrow and the entire length of the line is uniform over the entire surface of the pressure receiving plate. Preferably, it is dispersed.

Specifically, the line width of the tip of the linear protrusion is 0.01 to 1.0.
The total length of the line at the tip of the linear protrusion/diameter of the pressure plate is preferably 3 to 30.

However, the shape of the pressure-receiving plate is not limited to a disk-like shape, and an elliptical or square plate-like shape may also be used. The diameter is calculated and the ratio of total length of the line at the tip of the linear protrusion/diameter of the pressure plate is determined.

However, for example, the following rough guideline may be used as the length equivalent to the diameter of the pressure receiving plate.

In other words, if the pressure plate has an oval shape, the diameter is approximately the maximum diameter + the minimum diameter.

In the case of a regular polygon, the diameter of the circumscribed circle may be approximately determined as the diameter of the 1,000-circle encircle.

There are no particular restrictions on the arrangement or number of protrusions on the pressure receiving plate, and the line width at the tip of the linear protrusion and the ratio of total length of the line/diameter of the pressure plate are determined.

FIGS. 8 to 10 are schematic plan views showing examples of how the protrusions of the pressure receiving plate are arranged, and FIG. 8 is a staggered arrangement;
FIG. 9 is a radial arrangement, and FIG. 10 is a spiral arrangement.

The cross-sectional shape of the protrusion is not limited to the triangular shape shown in the drawings, but may be semicircular or the like, and can be arbitrarily selected in consideration of the compressive strength of the material of the pressure receiving plate.

Further, it may be preferable to provide the pressure plate with protrusions not only on one side but also on both sides.

Further, the pressure receiving plate of the present invention may also serve as an end plate constituting a part of a cylindrical container, as in the example shown in FIG.

Since the pressure receiving plate of the present invention comes into linear contact with the resin wall as described above, it is less likely to bite into the resin wall.

The size of the pressure receiving plate in the present invention depends on the size of the membrane separator, but it is usually a plate shape with a diameter of 50 to 500 mm and a thickness of 2 to 200 mm, and materials include metal, plastic, and fiber reinforced plastic. , ceramic, etc. are used.

The hollow fiber of the present invention preferably has an outer diameter of 10 to 1000 microns and a hollowness ratio of 3 to 30, and is not particularly limited as long as its membrane wall has permselectivity for fluids. The demolding process may be homogeneous, microporous, anisotropic, or composite.

Examples of the material for forming the hollow fibers include cellulose polymers such as cellulose acetate, polyamide, and polyvinyl alcohol.

There is no particular restriction on the arrangement of the hollow fibers in the hollow fiber assembly of the present invention, for example, a structure in which the hollow fibers are arranged parallel to the axial direction of the hollow fiber assembly, a structure in which the hollow fibers are arranged in a spiral shape around the central axis of the hollow fiber assembly, etc. There are structures in which hollow fibers are arranged and structures in which a knitted fabric made of hollow fibers is wound.

In the present invention, the resin forming the resin wall is preferably a fluid fluid before curing and becomes a hard solid upon curing. Typical examples thereof include epoxy resin, silicone resin, polyurethane resin, unsaturated polyester resin, etc. can be mentioned.

The cylindrical container in the present invention preferably has a cylindrical shape with a diameter of 50 to 500 mm and a length of 100 to 5000 mw, but is not necessarily limited to a cylinder, and may have a cylindrical shape with a polygonal cross section.

Further, the material of the tube and end plate constituting the cylindrical container may include steel, stainless steel, plastic, and the like.

Specific application examples of the membrane separation device of the present invention include gas permeation such as helium recovery and hydrogen purification, liquid permeation such as separation of bulk xylene from mixed xylene, oil/water separation, and paint separation from electrocoating wastewater. operations such as ultrafiltration, desalination of seawater, desalination of underground brine, purification of wastewater, and reverse osmosis such as the production of sterile water.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 are sectional views each showing an example of the membrane separation apparatus of the present invention. FIG. 3 is a plan view showing an example of the pressure receiving plate in the membrane separation apparatus of the present invention, FIG. 4 is a cross-sectional view of the pressure receiving plate in FIG. 3 taken along line A-A, and FIG. FIG. 2 is a cross-sectional view taken along line BB of Further, FIG. 6 is a plan view showing another example of the pressure receiving plate in the membrane separation apparatus of the present invention, and FIG. 7 is a plan view showing the pressure receiving plate of FIG.
- It is a sectional view cut along the C line. Furthermore, FIGS. 8 to 10 are schematic plan views showing examples of the arrangement of the protrusions on the pressure receiving plate. 1.21...Hollow fiber assembly, 2,22...
... Cylindrical container, 3,23... Pressure receiving plate, 4,5,
25... End plate, 6, 26... Hollow fiber layer, 7, 27...-TL perforated tube, 8, 9, 28, 2
9...Resin wall, 10.1L12.30,31,
32...Fluid inlet/outlet, 40°50...
Pressure receiving plate, 41, 51...Protrusion, 42°52...
... Tip of projection, 44.54 ... Fluid inlet/outlet, 45.55 ... Groove, 56 ... Groove.

Claims (1)

[Claims] 1 Consisting of a cylindrical container and a columnar hollow fiber assembly housed in the cylindrical container, the hollow fiber assembly includes a hollow fiber layer consisting of a large number of hollow fibers having selective permeability to fluids; and a resin wall located at at least one end of the hollow fiber layer,
In the membrane separation device, the hollow fibers constituting the hollow fiber layer penetrate at least one of the resin walls and are open to the outside thereof, and a pressure receiving plate is arranged adjacent to the hollow fiber opening surface of the resin wall. A membrane separation device characterized in that a linear protrusion is provided over the entire surface of at least one surface of the pressure receiving plate, and a tip of the protrusion is in contact with the hollow fiber opening surface.