JPH0355175B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) This invention has a liquid collecting section in which a membrane such as a UF membrane or an RO membrane is stretched, and a liquid passage gap on both sides of the surface of the membrane. A plurality of blocks are stacked in a row in the front and back direction facing each other in the liquid gap and are pressed between the front and rear end plates, and the block is compressed between the front and rear end plates. The present invention relates to a plate for a flat membrane device that performs solid-liquid separation in the same manner as a filter press, for separating a liquid that passes through and a concentrated liquid that does not pass through.

(Prior Art) Such a flat membrane device is known from Japanese Patent Publication No. 52-10113. As shown in FIGS. 22 and 23, this conventional device has a single movable end that can be moved along a horizontal support member 4 that is installed between a fixed end plate 2 and a fixed support plate 3 that are opposed in the front and back on a bed 1. Plate 2'; one or more partition plates 5, here three partition plates...
and; Suspend a plurality of plates 6 by placing them between the fixed end plate 2 and the partition plate, between the partition plates, and between the partition plate and the movable end plate, for example, the fixed end plate 2.
By tightening the bolt 7 passed between the movable end plate 2' and the movable end plate 2' with the nut 7', the block consisting of the partition plate 5 and a plurality of plates 6 is compressed between the end plates 2 and 2'.

On the front and rear surfaces of each plate 6, a washboard-like liquid collection recess 8 is formed by recessing two steps inside the peripheral edge made of a gasket, and a membrane 8 covering the liquid collection recess 8 is formed around the entire circumference of the first step. ' is stretched to form the liquid collection part 9,
Liquid passage ports 10 and 11 are opened at the top and bottom of this stage, and the upper liquid passage ports 10 and the lower liquid passage ports 11 of the board 6 for multiple sheets constituting each block are opposite to each other. Each liquid passage gap 9' between the plates
They are connected in a series with a distance between them. Each plate 6 has an extraction hole 12 through which the liquid that has passed through the membrane 8' and obtained in the liquid collection recess 8 is extracted from the periphery of the plate.

To carry out the separation, the stock solution is supplied by a pump to the liquid supply port 13 on the fixed end plate 2 that communicates with the upper liquid passage port 10 of the first block, and between the first and second blocks and between the third block. Each partition plate between the second block and the fourth block has a lower relay port 11' that communicates with the lower liquid passage port 11 of each block, and the partition plate between the second block and the third block is A device having an upper relay port 10' communicating with the upper liquid passage port 10 is used, and the movable end plate 2' is provided with a liquid drain port 14 communicating with the upper liquid passage port 10 of the fourth block.

As a result, the stock solution supplied from the liquid supply port 13 of the fixed end plate 2 to the continuous upper liquid passage port 10 of the first block passes through the liquid passage gaps 9' of all the plates of the first block to the membrane. contact and flow downward, at which time,
The liquids that have passed through the membrane and obtained in the liquid collecting recesses 8 are discharged from the respective extraction holes 12, and the stock liquid that has not passed through the membrane is discharged from the partition between the lower liquid passage port 11 of the first block and the second block. It flows through the lower relay port 11' of the plate into the series of lower liquid passage ports 11 of the second block, contacts the membrane in the liquid passage gaps 9' of all the plates of the second block, and then flows upward. At this time, the liquid that has passed through the membrane and obtained in the liquid collection recess is discharged outside the plate through the extraction hole 12, and the stock liquid that has not permeated is transferred from the upper liquid passage port of the second block to the third block. 3rd through the upper relay port 10' of the partition plate between the block and
It flows into a series of upper passage ports 10 of the block and now flows in a downward flow through the passage gaps 9' of all plates of the third block against the membrane.

In this way, the liquid that has flowed upward (or downward) through each liquid passage gap of the previous stage block by contacting the membrane will flow in the opposite direction through the liquid passage gap of the next stage block by contacting the membrane. The liquid flows in a downward flow (or upward flow), repeats a meandering flow in the vertical direction for each block, and flows in contact with the membrane through the liquid passage gap in the final stage, here the fourth block. The concentrated liquid that has not passed through the membrane is discharged from the drain port 14 of the movable end plate.

(Problem to be solved by the invention) By the way, in such membrane separation, if the liquid does not flow through the liquid passage gap at a constant flow rate, a concentration distribution will occur on the membrane surface, and the yield of the liquid passing through the membrane will vary. It has the property that (flux) decreases.

In the above conventional example, a block is constructed by stacking multiple plates in a line in the front-rear direction, so the amount of stock solution required to flow through the liquid passage gap of one plate in contact with the membrane to obtain the required flow rate is Q. If 10 boards make up one block, then 10×
Supply port 13 for stock solution with a large capacity pump of Q=10Q
It is necessary to supply the same amount of water to the equipment, which not only increases equipment costs but also increases running costs.

Furthermore, a large amount of the liquid flowing into the liquid passage ports 10 at the upper or lower part of the series of plates constituting each one block is supplied to the liquid passage gap on the downstream side, and the liquid is supplied to the liquid passage gap on the upstream side. The amount tends to decrease more than that on the downstream side, and the flow velocity in the liquid passage gap on the upstream side becomes smaller, resulting in the problem that the membrane on the upstream plate is easily clogged with solids in the liquid. be.

(Means for Solving the Problems) Therefore, the present invention provides a solution supply port for flowing the stock solution, which is separated by a removable partition piece at one end of each of the liquid collection parts on which a membrane is stretched, and is similarly cut out at the other end. A liquid drainage port for flowing the concentrated liquid is provided separated by a partition piece that can be used, and a pair of closable liquid passage holes are provided at one end and the other end of the liquid collecting portion on both sides, respectively, through which the concentrate passes through. It is characterized by

(Function) As a result, one of the plates that are stacked in a row in the front and rear direction to form a block has the partition piece between the liquid collection part and the liquid supply port removed, and all the liquid passage holes in the liquid collection part are removed. Close it and use it for liquid supply, and remove the partition piece between the liquid collection part and the liquid drainage port on the other one, and close all the liquid passage holes in the liquid collection part to use it for liquid drainage.
The other plates located between the liquid supply and drain plates alternately close the liquid passage holes on one end side and the liquid passage holes on the other end side, and thus the entire block comprising the single plate is closed. The undiluted solution can be flowed in a meandering manner by sequentially changing its direction from one direction to the other through the liquid passage gap of the plate.

(Embodiment) In each of the illustrated embodiments, the same components as in the conventional example shown in FIGS. 22 and 23 are denoted by the same reference numerals.
Furthermore, for convenience, each embodiment will be described with the front and back as left and right.

Figures 1 and 2 show an embodiment of a plate that can be called an original plate according to the present invention.The plate is a vertically long rectangle like the conventional example described above, and the film 8' is applied to both sides of the plate. A liquid supply port 16 is provided above the upper end of the liquid section 8, separated by an upper partition piece 15, and similarly, a liquid drain port 18 is provided below the lower end, separated by a lower partition piece 17.
, and the liquid collection recesses 8 and 8 on both sides of the plate are opened at both ends, and an upper liquid passage hole 19 is opened in the upper part, and a lower liquid passage hole 20 is opened in the lower part.

In this embodiment, the top of each upper partition piece 15,
A concave surface 21 at the same level as the cross section where the membrane 8' is stretched is provided below the lower partition piece 17, and a liquid supply port 16 and a liquid drain port 18 are provided.
are provided with openings at both ends of the concave surface, but for example, the liquid drain port 1 may be placed along the upper edge of the upper partition piece 15 along the lower edge of the liquid supply port 16, or the liquid drain port may be placed along the lower edge of the lower partition piece 17.
In the case where the upper edge of 8 is aligned, this concave surface 21 can be omitted.

Further, each of the upper and lower partition pieces 15 and 17 can be easily cut out with a grinder, but in order to facilitate cutting, a substrate 6' made of hard vinyl chloride or the like is used, which is made up of thin fragile parts 15' and 17'. It is preferable to mold it integrally with.

Figure 3 shows six types of plates 6a and 6b from the above plates.
...Make 6f, of which 6b, 6c, 6d, 6
4 sets of blocks each containing 4 types of e.
, a plate 6a is sandwiched between the pairs and between the pairs, a plate 6f is sandwiched between the pairs, and the entire plate is sandwiched between the fixed end plate 2 and the movable end plate 2'. The case is shown in which a flat membrane device is formed by pressing.

Figures 5 to 10 are front views of the six plates mentioned above.
The left half shows the left side of each plate in FIG. 3, the right half shows the right side, and X indicates a closed liquid passage hole.

The plate 6a is for liquid supply, and as shown in FIG.
Block 20 as well. To close each liquid passage hole, as shown in Fig. 4, a blind plate 22 or plug 2 that fits snugly into the hole is used.
Apply adhesive to 3 and press to fix it, and then attach the membrane 8'
Use one that does not have holes at positions corresponding to the liquid passage holes.

For the plates 6b of the set adjacent to the liquid supply plate 6a, only the upper partition piece on the left side facing the plate 6a is removed, and only the upper part 19 of the liquid passage hole is closed, and the lower part 20 is left open. To open the liquid passage holes, as shown in Figure 4, holes of the same size were made in the corresponding parts of the membranes on both sides, and adhesive was applied from the membrane holes into the respective liquid passage holes. The eyelet-shaped clamp 24 is pushed in and fixed to prevent the stock solution from leaking into the liquid collecting recess through the membrane pores.

Plate 6 adjacent to the liquid supply plates 6a of the set and set
b may be formed in the same manner as described above, and its orientation may be reversed so that the surface of the upper partition piece cut away faces the liquid supply plate.

As a result, the raw liquid flowing through the series of liquid supply ports of each plate is transferred to the liquid supply plate 6a and the adjacent plate 6b of each set. The stock solution flows in a downward flow into the liquid passing gaps 9', 9', and the liquid that permeates through the membrane while flowing in contact with the membrane enters the liquid collection recess 8 and is extracted from the extraction hole 12, Since the lower partition pieces 17 of both plates 6a and 6b face each other and close the lower end of the liquid collecting section, the liquid that has not drained passes through the lower liquid passage hole 20 of the plate 6b. In addition, in FIG. 3, D indicates a state in which the upper or lower partition pieces face each other and close the upper or lower end of the liquid collecting section.

The plate 6c adjacent to the plate 6b closes only the lower liquid passage hole 20 as shown in FIG. 7, and the plate 6d adjacent to the plate 6c closes only the upper liquid passage hole 19 (the eighth
The plate 6e adjacent to the plate 6d closes the lower liquid passage hole 20, and the lower partition piece 17 on the surface facing the plate 6f is removed (Fig. 9), and the plate 6f has the upper and lower liquid passage holes 19, 20 and cut out the lower partition pieces 17 on both the left and right sides (FIG. 10).

As a result, the stock solution that has entered the lower liquid passage hole 20 of the plate 6b is transferred to the liquid passage gap 9' between the opposing plates 6b and 6c.
After contacting the membrane and flowing upward through plate 6c
The liquid passes through the upper liquid passage hole 19 and flows downward through the opposed liquid passage gap between plates 6c and 6d, and then passes through the lower liquid passage hole 20 of plate 6d and flows upward through the opposed liquid passage gap between plates 6d and 6e. The liquid flows counter-currently, passes through the upper liquid passage hole of the plate 6e, flows downward through the liquid passage gap of the plate 6e facing the end plates 2 and 2' in the pair and the pair, and flows downward through the liquid passage gap of the plate 6e facing the end plates 2 and 2' in the pair and the pair. The concentrated liquid that flows downward through the liquid passage gap and thus does not pass through the membrane flows into a series of drain ports 18 and is discharged because there is no lower partition piece 17 that closes the lower end of the liquid passage gap.

In short, in this embodiment, liquid is supplied in a downward flow between the sets, between both sides of the liquid supply plate 6a between the sets, and the opposing surface of the adjacent plate 6b, and between the sets. Solid-liquid separation is carried out by meandering the stock solution in the vertical direction, with the blocks facing the fixed end plates and the sets of blocks facing the movable end plates.
By increasing or decreasing the number of d, the number of plates used in one block can be arbitrarily determined.

Figure 11 shows five types of plates 6g, 6h, 6i, 6j, and 6k made from the original plates in Figures 1 and 2.
Four sets of blocks each containing a seed are constructed, and these are sandwiched between both end plates 2 and 2', and each block is moved up and down in the same direction toward the fixed end plate or the movable end plate. This is the case when a flat membrane device is used to meander the stock solution.

Boards 6h, 6i, 6j, and 6k are the aforementioned boards 6.
Same as b, 6c, 6d, 6e. The liquid 6g closes the upper and lower liquid passage holes 19 and 20, and cuts off the upper partition piece on the right side of the plate 6h (6b) opposite to the left side without the upper partition piece, and the lower partition piece on the left side.

As a result, the stock solution flowing through the series of liquid supply ports 16 flows downward into the liquid passage gaps between the plates 6g and 6h, and then flows upward through the liquid passage gaps between the plates 6h and 6i, and then flows upward through the liquid passage gaps between the plates 6h and 6i. The liquid flows downward through the opposed liquid passage gaps, flows upward through the opposed liquid passage gaps between plates 6j and 6k, and finally flows downward through the opposed liquid passage gaps between plates 6k and 6g. The concentrate is discharged into a series of drains 18 .

As shown in Figures 1 and 2, the plate has an upper liquid passage port 16, a liquid collection part 8, and a lower liquid passage hole 18 formed on each side in a cross-shaped shape. A central vertical beam 25 provided integrally with the partition pieces 15 and 17 of
A plurality of them may be formed, such as two on both sides of the partition.

Further, as shown in FIGS. 19, 20, and 21, partition pieces 15 and 17 are provided to surround the liquid supply port 16 and liquid drain port 18, and liquid passage holes 19 and 20 are provided between the liquid collection recess 8 and the above-mentioned supply port. It may be provided between the liquid port 16 and the liquid drain port 18. In this case, when cutting out the partition piece, it is only necessary to cut out only the liquid collecting recess side without cutting out the entire partition piece. Note that the gasket 26 for sealing between the opposing plates is provided by adhesive or the like only at the peripheral edge of the same side as the recess on one side of each plate.
When stacked one on top of the other, the surface of the opposite plate that does not have a gasket is brought into contact with the gasket.

Further, the above-mentioned partition pieces 15, 17, liquid supply port 16, and liquid drain port 18 are designed to be cut out or closed at necessary locations, but when integrally molding the substrate 6' by injection molding, Then, a core may be inserted into the cut or closed part and molded to obtain the several types of plates mentioned above. In that case, it is convenient because machining for excision or operation for occlusion can be omitted.

Therefore, in the present invention, when the term "resectable" or "resectable" and "occlusion" are used, it should be understood that the term "resectable" or "resectable" and "occlusion" also includes cases where injection molding is used as described above.

(Effects of the Invention) In the flat membrane device constructed with the plates of the present invention, the stock solution flows in contact with the membrane while meandering sequentially through the liquid passage gap between the plurality of opposing plates constituting one block. Assuming that the amount of stock solution flowing through the liquid passage gap of one plate to obtain the required flow rate is Q, the formula is Q x the number of blocks, regardless of the number of plates that constitute one block.

Therefore, for example, in the conventional example, if 10 plates constitute one block and the number of blocks is 4, the required amount of stock solution is Q x 10 (number of plates constituting one block).
In contrast, in the present invention, Q×4 (number of blocks)
This means that while using the same 40 plates, a pump with a much smaller capacity can be used, resulting in lower equipment and running costs.

Furthermore, since the stock solution flows in a meandering manner through the liquid passage gaps in the block, the amount of stock solution flowing through the downstream liquid passage gaps is smaller than that of the upstream liquid passage gaps, but the flow rate is Since it is almost constant, the membranes of the upstream plate and the downstream plate are less likely to be clogged with solids in the liquid.

In addition, the block can be constructed by simply forming the required plate by cutting out a pair of partition pieces from a single plate or blocking a pair of liquid passage holes, and there is no need to use foreign materials such as partition pieces. It is easy to manufacture.

[Brief explanation of drawings]

Figure 1 is a partially cross-sectional front view of an embodiment of the plate in the molded state, Figure 2 is a sectional view taken along the - line in Figure 1, and Figure 3 is a cross-sectional view of the plate in Figure 1. A schematic side view of an example of the constructed flat membrane device, FIG. 4 is an enlarged sectional view of the part surrounded by the line in FIG. 3, and FIGS. FIG. 11 is a front view of the plate, and FIG. 11 is a schematic side view of another example of a flat membrane device constructed using the plate shown in FIG.
From the figures, Fig. 16 is a front view of each plate used in the flat membrane device of Fig. 11, Fig. 17 is a front view of another embodiment of the plate in a molded state, and Fig. 18 is A of Fig. 17. 19 is a front view of yet another embodiment of the plate in a molded state, and FIG. 20 is a sectional view taken along the line B.
FIG. 9 is a step view taken along line A-B, FIG. 21 is a step view taken along line C-D in FIG. 19, FIG. 22 is a side view of the entire conventional device, and FIG. 23 is FIG. In the figure, 2 is a fixed end plate, 2' is a movable end plate,
6 is a plate, 8' is a membrane, 9 is a liquid collection part of the plate, 9' is a liquid passage gap, 15 and 17 are partition pieces, 16 is a liquid supply port,
18 is the drain port, 19 and 20 are the liquid inlets,...
, indicates a block made of multiple boards.

Claims (1)

[Scope of Claims] 1. A liquid collecting part with a membrane stretched thereon, and a liquid passage gap on both sides of the surface of the membrane, and a plurality of membranes facing each other in the liquid passage gap and stacked in a line in the front and back direction. A flat membrane device that comprises a block that is pressed between end plates of the membrane, and separates the stock solution into a liquid that has passed through the membrane and a concentrated liquid that has not passed through the membrane by flowing the stock solution in contact with the membrane through the liquid passage gap. In the plate; one end of each of the liquid collecting parts on both sides is separated by a removable partition piece, and the liquid supply port is for flowing the concentrated liquid, and the other end is also separated by a removable partition piece, and is for flowing the concentrated liquid. 1. A plate for a flat membrane device, characterized in that a liquid drainage port is provided, and a pair of closable liquid passage holes are provided at one end and the other end of the liquid collecting portions on both sides, respectively, through which the stock liquid passes through.