JPS6249902A - Liquid separator - Google Patents

Abstract

PURPOSE:To reduce the pressure drop of the titled separator and to fully utilize the separation capacity of all the elements by providing a bypass circuit or a short circuit and distributing and supplying a raw liq. to the plural liq. separation elements which are packed in series. CONSTITUTION:In the liq. separator wherein plural liq. separation elements 2 are packed in a vessel 1 in series, an opening part 11 is provided to a sealing member 15 present between the vessel 1 and the liq. separation element 2 and hence the liq. which has not been substantially separated in the preceding element can be introduced into the liq. separation elements after the second element. Besides, an opening part may be furnished to a part of the liq. separation element and a grooved part provided on the inner wall of the vessel. A bypass pipe equipped with a flow regulating mechanism, etc., may be provided to the vessel.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an improvement of a liquid separation membrane device using liquid separation membrane technology. More specifically, by supplying an appropriate amount of stock solution to each of a plurality of liquid separation elements loaded in series in a container, the pressure loss that occurs when the stock solution passes through the liquid separation elements is reduced. Regarding the technology.

[Prior Art] Liquid separation membrane devices using liquid separation membranes are already well known. For example, Japanese Patent Publication No. 44-14216, Japanese Patent Publication No. 5
2-5431, etc.

In actual use of such a liquid separation membrane device, in order to realize a more economical device, as many liquid separation elements (hereinafter referred to as ``elements'') as possible are placed in one container (hereinafter referred to as ``vessel'').

It is desirable to use liquid separation membrane devices (hereinafter referred to as "modules") loaded in series. However, an increase in the number of elements leads to an increase in pressure loss in the module, and in reality, the number of elements that can be placed in one vessel is limited depending on the amount of separated liquid.

In modules that use reverse osmosis membranes, it is necessary to maintain the flow velocity at the membrane surface above a certain level in order to prevent performance degradation due to concentration polarization (uneven distribution). Therefore, the final element seen from the stock solution supply side in the vessel has a certain predetermined flow rate Q.
must be supplied. In other words, it is the number of elements in one cell. Therefore, in reverse osmosis membrane modules, the pressure loss of the module becomes even greater.
The number of elements that can fit into one vessel is roughly limited. Furthermore, as the performance of the membrane improves and the amount of liquid separated by the element increases, this tendency becomes even more pronounced.

FIG. 9 shows a schematic diagram of an example of the entire prior art.

Four elements 21 to 24 are loaded in series in the vessel 1. The stock solution 8 is supplied into the vessel 1 through the inlet pipe 4 by the pump 7 .

In the conventional example, the gaps between the vessel 1 and the elements 21 to 24 are sealed by seal members 31 to 34. Therefore, the stock solution first passes through the liquid separation membrane surface of the element 21, and the pure liquid separated by the membrane is separated by the membrane. The pure liquid is taken out of the vessel 1 through the central pure liquid take-out vibro.

On the other hand, the remaining stock solution is supplied to the next element 22, and the similarly separated pure liquid is taken out from the pure liquid extraction vibro, and is thus successively processed in multiple stages. Finally, the separated residual liquid is taken out from the residual liquid discharge pipe 5.

This is due to the fact that there are steps. Although any means may be used, the following means can be adopted as preferred specific means.

■ Providing an opening in the sealing member that exists between the vessel and the element.

■ Providing an opening in a part of the element ■ Providing a groove in the inner wall of the vessel.

■ Install a bypass pipe in the vessel.

■ Similarly, a flow rate adjustment mechanism should be provided in the bypass pipe.

Next, the present invention will be explained with reference to the drawings.

FIG. 1.2 shows one embodiment of the present invention, in which an opening 11 is provided in a seal member 15 existing between the vessel 1 and the element 2. The sealing member 15 may be of any type as long as it is commonly used, such as a ■ lip, an O-ring, an × ring, or a △ seal.

The preferred size of the opening 11 is approximately 0.5 to 5 mm when the element diameter is 2 oomm.

Such aperture area can of course vary proportionally as the element diameter changes. The number of openings 11 can be arbitrary.

Further, in the case of a V-lip, it is preferable that the opening is at least 2 mm or more away from the tip of the lip. This is to keep the strength strong and the opening stable. A metal or plastic pipe may be inserted into the opening. Further, it is practical that the opening diameter is about 1 to 5 mm. In order to equalize pressure loss, it is desirable that such openings have a higher opening ratio in order from the stock solution supply side in the vessel.

FIG. 3 shows another embodiment of the invention, in which the element 2 itself has short path passages (openings) 11.
12 will be provided. These short path passages 11, 12 may be provided in any part of the element, but in order to avoid damaging the separation membrane and ensure long-term stable use, it is preferable to provide it in a rigid part. Rigid parts include the part to which the membrane is fixed, the outer frame, the seal holder, etc. Among these, the U-seal holder is particularly preferred because it is easy to process. The size, number, etc. of the openings are as described above.

FIG. 4.5 shows another embodiment of the present invention, and shows an example in which a groove 13 is provided in the inner wall of the vessel. The groove portion 13 may have any shape, such as a U-shape, a ■-shape, or a concave shape. The size, number, etc. of the grooves are as described above.

6 to 8 show another embodiment of the present invention,
An example in which the vessel is provided with bypass pipes 14 (141 to 143) is shown. Although FIG. 6 shows an example in which three bypass pipes are provided, as described above, any number of bypass pipes may be provided as long as it is one or more. It is preferable that the bypass pipe 14 is provided with a flow rate adjustment mechanism.

FIG. 7 shows an example in which a valve 15 is provided as a flow rate adjustment mechanism, and FIG. 8 shows an example in which an orifice 16 is provided. Alternatively, the diameter of the tube may be set appropriately. The flow resistance due to the flow rate adjustment mechanism may vary depending on the flow resistance value of the element, but in the present invention, the following range is empirically preferred.

△P=(2X10 ~1X10-3>・Q2 [However, Q
represents the amount of liquid passing through the bypass pipe (unit: Q/m1n), and ΔP represents pressure loss (unit: -/i). ] In the present invention, any separation membrane may be used. Specifically, they include cellulose acetate, polyamide, crosslinked polyamine, crosslinked polyamine/polyether, crosslinked polyether, polyacrylonitrile, polyether, and sulfonated polysulfone. These may be used in combination as appropriate. Membrane forms of reverse osmosis membranes made from these membrane materials include asymmetric membranes and composite membranes. Membrane element structures that can be used in water purification devices include spiral type, hollow fiber type, tubular type, and plate and frame type.

[Example] Example 1 Experiments were conducted using the apparatus shown in Figure 1.2.

The element was spiral-shaped, with a diameter of 200 mm and a length of 1 m, and the membrane material was a material whose main component was crosslinked polyether (commercial product manufactured by Bunshi Co., Ltd.).Seal member A V-lip was used.

Table 1 shows the conditions and effects.

In the present invention provided with the bypass circuit shown in Table 1, the pressure loss of the module can be reduced. Furthermore, when the pressure was kept the same, the amount of water produced was approximately 1.50% higher than that of the conventional technology.

Example 2 An experiment was conducted in the same manner as in Example 1 using the bypass circuit shown in FIG. Conditions and effects are shown in Table 2.

In the present invention provided with the bypass circuit shown in Table 2, the pressure loss of the module can be reduced. Furthermore, when the pressure was kept the same, the amount of water could be increased by about 10% compared to the conventional technology.

[Effects of the Invention] Since the present invention has the above-described configuration, it has the following excellent effects.

■ Module pressure loss can be reduced easily and at low cost.

- As the module pressure drop decreases, the number of elements that can be loaded into one vessel can be increased, and costs can be reduced as the number of vessels decreases.

■Furthermore, as membrane performance improves and the element produces a higher amount of water, the effects of ■ and ■ become more significant.

■ It can be used stably for a long period of time and prevents membrane damage.

[Brief explanation of drawings]

FIG. 1.2 shows one embodiment of the present invention, in which an opening 11 is provided in a seal member 15 existing between the vessel 1 and the element 2. FIG. 3 shows another embodiment of the invention, in which short path passages (openings) 11, 12 are provided in the element 2 itself. Figure 4.5 shows another embodiment of the invention,
An example is shown in which a groove portion 13 is provided on the inner wall of the vessel. 6th to 8th
The figure shows another embodiment of the present invention, and shows an example in which a vessel is provided with bypass pipes 14 (141 to 143). Patent applicant Toshi Co., Ltd. No. 3

Claims (6)

[Claims] (1) In a liquid separation device using membrane separation technology in which a plurality of liquid separation elements are loaded in series in a container, liquid that does not pass through the membrane surface of the liquid separation element located relatively on the inlet side of the raw liquid is A liquid separation device characterized by being provided with means for introducing a stock liquid from an inlet to a second or subsequent liquid separation element. (2) The means for introducing the stock solution into the second and subsequent liquid separation elements from the inlet is an opening in a sealing member that is present between the container and the liquid separation element. The liquid separation membrane device described in (1). (3) Claim (1) characterized in that the means for introducing the stock solution into the second and subsequent liquid separation elements from the inlet is an opening provided in a part of the liquid separation element. liquid separation equipment. (4) The liquid separation device according to claim (1), wherein the means for introducing the stock solution from the inlet to the second and subsequent liquid separation elements is a groove provided in the inner wall of the container. . (5) The liquid separation device according to claim (1), wherein the means for introducing the stock solution from the inlet to the second and subsequent liquid separation elements is a bypass pipe provided in the container. (6) The liquid separation device according to claim (5), wherein the bypass pipe is provided with a flow rate adjustment mechanism.