JPS6229489Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a diaphragm attachment device for a finger-type diaphragm electrolytic cell. More specifically, the present invention relates to a diaphragm mounting device with a simple structure that allows easy, rapid and reliable mounting and removal of diaphragms, particularly cation exchange membranes.

The use of a diaphragm such as an ion exchange membrane has been proposed and put to practical use as a method for producing caustic alkali by electrolyzing an aqueous alkali metal halide solution, especially an alkali metal chloride solution.
Recently, the problem of pollution caused by mercury laws has become a hot topic.
There is a tendency for it to be used more and more frequently.

Among the diaphragm methods, filter press type electrolytic cells are extremely common, but so-called finger-type diaphragm electrolytic cells are being actively used and developed with the aim of increasing capacity and reducing equipment investment and operating costs.

Here, a finger type diaphragm electrolytic cell has a plurality of fingers each having a cathode vertical electrolytic surface,
a plurality of anodes interposed between each finger and having an electrolytic surface parallel to the vertical electrolytic surface; a diaphragm support member that covers at least the upper and lower horizontal surfaces of the fingers, leaving the corresponding upper and lower portions of the anode; and the diaphragm. A type comprising a diaphragm extending and fixed along the cathode vertical electrolytic surface of the finger by a supporting member, for example, as disclosed in Japanese Patent Application No. 54-160999 already filed by the present applicant.
No. 54-161000 and No. 54-161001, and further included the structure proposed by No. 54-161000 and No. 54-161001, and further included the structure proposed in 1962 by Reinhold, Ichiiku City. Publishing. Corporation (REINHOLD PUBLISHING CORPORATION)
J.A. will be published. S. Sconce (JS
“CHLORINE-Its Manufacture, Properties, and Uses,” edited by SCONCE)
In addition to the finger-type electrolytic cell described on page 93 of ``Uses'', the flattened electrolytic cell described in the above-mentioned document. Tube. type. It is also a general term for flattened tube-type construction, that is, electrolytic cells with a flattened cylindrical structure.

In such a finger-type diaphragm electrolytic cell, in order to support and fix the diaphragm made of a cation exchange membrane, a microporous membrane, etc. to the diaphragm support member, a protruding edge is generally provided along the peripheral edge of the diaphragm support member,
A method has been adopted in which the edge of the diaphragm is attached and fixed onto the convex edge, and various efforts have been made to achieve reliable fixation or to facilitate attachment and detachment.

In a similar attempt, the present applicant has proposed a diaphragm attachment device for an alkali chloride electrolytic cell in which a diaphragm is attached to the convex edge of a support member by bolting using a restraining plate through packing. However, since this proposed device uses a flat holding plate, the bending stress in the thickness direction is small, and when tightened with a bolt or nut, the area around it is tightly tightened.
A serious defect was experienced in that a portion slightly away from the tightened portion had a tendency to lift up and separate, making the seal more likely to be incomplete. In order to avoid this, it was effective to some extent to reduce the bolt tightening pitch, but to completely eliminate the waving phenomenon of the holding plate, it is necessary to further reduce the bolt spacing, that is, use a large number of bolts. However, there is a disadvantage in that it makes the work unnecessarily complicated and increases costs.

The present invention has been made in view of the above-mentioned problems, with the purpose of providing an improved diaphragm attachment device with a simple structure that allows for easy and quick attachment and removal of the diaphragm and a completely reliable seal. , its features are: a plurality of fingers with cathode vertical electrolytic surfaces; a plurality of anodes interposed between each finger and having electrolytic surfaces parallel to the vertical electrolytic surfaces; A finger-type diaphragm electrolytic cell comprising: a diaphragm support member that covers at least the upper and lower horizontal surfaces of the finger, leaving a considerable portion; and a diaphragm extending and fixed along the cathode vertical electrolytic surface of the finger by the diaphragm support member. ,
The diaphragm support member is constructed of an angular restraining plate capable of covering the upper surface and outer wall surface of the protruding edge protruding from the periphery of the diaphragm support member, packing, and fastening tools using bolts and nuts. Therefore, the above-mentioned attachment device clamps the edge portion of the diaphragm between the outer wall surface of the convex edge and the retainer plate via packing, and tightens the retainer plate and the convex edge with the tightening tool, thereby attaching the finger. It is configured as a type electrolytic cell.

Hereinafter, the device of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view showing a finger cathode in a typical example of a conventionally proposed finger-type diaphragm electrolytic cell. In the figure, an anode plate (not shown) is provided with a cathode vertical electrolytic surface 1 made of net-like or porous metal, rod-like or interdigital metal, and between a plurality of fingers 2, 2', etc. arranged in parallel, respectively. (not shown) is interposed so that its electrolytic surface is parallel to the cathode vertical electrolytic surface 1. Such a finger cathode has diaphragm support members 3, 3 that cover at least both the upper and lower horizontal surfaces of the fingers 2, 2', respectively, leaving the corresponding portions above and below the anode.
It is equipped with

The diaphragm supporting members 3, 3' are provided with protruding edges 4 along their peripheries, and serve to extend and fix the diaphragms along the cathode vertical electrolytic surfaces 1 of the fingers 2, 2', . . ., as will be described later.

The diaphragm support members 3, 3' are made of synthetic resin or metal that is heat resistant and corrosion resistant to the catholyte and anolyte. When using metal materials, the finger cathodes and the diaphragm support member 3,
3'. Although a cation exchange membrane or a microporous membrane can be used as the sheet-like diaphragm extending along the vertical electrolytic surface 1 of such a finger cathode, a cation exchange membrane or a microporous membrane can be used in the electrolytic cell to which the present invention is applied. Membranes are preferably used.

The cation exchange membrane is preferably a polymer having a fluorine-based skeleton, and examples of the exchange group include sulfonic acid groups, carboxylic acid groups, phosphoric acid groups, etc. alone or in combination of two or more types.

Next, an example of a diaphragm attachment device for fixing a sheet-like diaphragm to the diaphragm support members 3, 3 will be explained with reference to FIG. 2 and subsequent figures.

FIG. 2 is a partially cutaway perspective view showing a conventionally proposed mounting device for attaching a diaphragm to a finger-type diaphragm electrolytic cell, FIG. 3 is a partial vertical sectional schematic diagram of FIG. 1, and FIG. It is an enlarged sectional view of the main part.

In these figures, conventional diaphragm support members 3,
The peripheral part of the diaphragm 6 is inserted between the outer wall of the convex edges 4, 4' of 3' and the flat plate-like restraining plate 5 that is in contact with the outer wall through the packing 7, and the whole is secured with bolts and nuts 8. This was done by tightening and fixing.

In the case of such a conventionally proposed device, as described above and as shown in FIG. Because the bolts tend to break, it was necessary to shorten the bolt spacing.

FIG. 6 is a vertical sectional view showing the main parts of the device of the present invention, and FIG. 7 is a perspective view thereof. In the figure, the diaphragm 6 and packing 7 set along the outer wall of the convex edge 4 of the diaphragm support member 3 are provided with a metal plate having a uniform L-shaped basic cross-sectional shape along the longitudinal direction, that is, an angular holding plate. 5, its horizontal plate portion 9 has a convex edge 4
The bolt/nut 8 is in contact with the outer wall of the
tightened by. Since the angular restraining plate 5 has an L-shaped basic cross-sectional shape, the reinforcing action of the horizontal plate part 9 imparts a significantly increased bending stress in the thickness direction to the vertical plate part 10, which prevents bolts and nuts from tightening. Due to strong tightening, no distortion occurs in the vertical plate section 10.

Most preferably, the angle formed by the horizontal plate portion 9 and the vertical plate portion 10 is substantially a right angle, and the lower edge of the vertical plate portion 10 is bent further outward (FIG. 7). This is more desirable in terms of providing the effect of preventing the impact phenomenon and applying a uniform pressing force along the outer wall surface of the convex edge 4.

It is desirable that the length of the horizontal plate portion 9 is sufficient to cover the upper surface of the convex edge 4; if it is too short, the force for preventing distortion of the vertical plate portion 10 will be small, which is inappropriate. Moreover, if it is too long and protrudes inward beyond the convex edge, it is not preferable because it will hinder the tightening operation of bolts and nuts.

The angular holding plate and bolts/nuts applied to the present invention are preferably made of a metal material that is corrosion resistant to electrolyte, that is, alkali resistant and chlorine resistant. Examples of such metal material include titanium, Examples include tantalum, niobium, alloys containing at least 90% of tantalum, aluminum, steel, copper, etc. coated with the above-mentioned corrosion-resistant metals.

Since the present invention is constructed as described above, it is possible to prevent distortion and deformation of the holding plate due to the tightening of bolts and nuts, and to significantly increase the distance between the bolts and nuts (bolt pitch). Uniform and strong diaphragm attachment can be performed over a long distance. Incidentally, while the conventional device required a bolt pitch of 80 mm to barely overcome the waving phenomenon of the restraining plate, the angular restraining plate of the present invention, which was made from material of the same thickness, was applied. In that case, it was possible to increase the bolt pitch to 120mm or more.

As is already clear from the above description, according to the present invention, the diaphragm can be attached extremely easily and quickly along the side surface of the finger cathode of a finger-type diaphragm electrolytic cell, and with great workability. The mounting condition is secure and strong, and the attachment is uniform and perfect sealing is guaranteed.

Furthermore, there are many advantages in that the removal and disassembly of the diaphragm can be carried out much more easily and quickly as the number of bolts and nuts is reduced.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a finger cathode of a finger-type diaphragm electrolytic cell, Figs. 2 to 5 are schematic explanatory diagrams of a conventionally proposed diaphragm mounting device, and Fig. 6 is a diaphragm installation device using the device of the present invention. A sectional view showing the installed state, and FIG. 7 is a partial perspective view thereof. 1... Cathode vertical electrolytic surface, 2... Finger,
3, 3... Diaphragm support member, 4... Convex edge, 5... Holding plate, 6... Diaphragm, 7... Packing, 8... Bolt/nut, 9... Horizontal plate portion, 10... Vertical plate part.

Claims (1)

[Claims for Utility Model Registration] 1. A plurality of fingers each having a cathode vertical electrolytic surface, a plurality of anodes interposed between the fingers and having an electrolytic surface parallel to the vertical electrolytic surface, and a plurality of anodes each having an electrolytic surface parallel to the vertical electrolytic surface. A finger comprising a diaphragm support member that covers at least the upper and lower horizontal surfaces of the finger, leaving the upper and lower portions, and a diaphragm that is extended and fixed along the cathode vertical electrolytic surface of the finger by the diaphragm support member. The finger type diaphragm electrolytic cell is characterized by comprising an angular holding plate that can cover the upper surface and outer wall surface of the convex edge protruding from the periphery of the diaphragm support member, packing, and fastening tools using bolts and nuts. Diaphragm installation device for electrolytic cells. 2. The diaphragm mounting device for a finger-type electrolytic cell according to claim 1, wherein the angle formed by the two flat plate portions constituting the angled restraining plate is substantially a right angle. 3. Utility model registration claim 1, in which the angular restraining plate is formed by further bending the lower edge of the flat plate portion that should cover the outer wall surface of the convex edge outward.
The diaphragm attachment device for a finger-type electrolytic cell according to item 1 or 2.