JPH0725214Y2 - Membrane filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an improvement of a liquid filter using a membrane.

<Prior Art> Conventionally, as a filter for liquid, as shown in FIG. 3, membranes 14 'and 14' are formed on both sides of a disk type plastic spacer 11 '.
A plurality of units A ′ for welding the outer peripheral portion and the inner peripheral portion of each membrane to the spacer are stacked, and the spacer central portions of the adjoining units are welded to each other to form the membrane filter body 1 ′. , One end of a central port 10 '(permeated water collecting port) of the membrane filter body 1'is closed by welding an end plate 2', and a container piece having a permeated liquid outlet 411 'and an air vent 412' A membrane filter body 1'is attached to the permeated liquid outlet 411 'of 42'.
It is known that the other end of the central port is welded and another container piece 41 'having a stock solution injection port 421' is bonded to the one container piece 42 '.

When filtering the undiluted solution, the undiluted solution is fed into the container through the undiluted solution injection port, the air in the container is exhausted from the air vent port, and after this exhaust, the air vent port is closed to pressurize the undiluted solution in the container. There is. The permeated liquid that has permeated the membrane by pressurization of this undiluted solution travels along the groove on the spacer surface and reaches the central permeated water collection port through the communication passage hole. Take the exit. At the initial stage of taking out the permeated liquid, the air in the collection port is mixed as bubbles in the permeated liquid. Therefore, depending on the use of the liquid, it is necessary to use the permeated liquid after confirming that the bubbles have disappeared. (For example, in the case of filtering a developing solution or a resist solution in a semiconductor manufacturing process, if air bubbles are mixed in the filtered solution, the developing solution or the resist cannot be uniformly applied to the wafer, resulting in an unpainted residue and printing defects. ).

<Problems to be solved> In the above filter, since the membrane filter main body is fixed to the container by cantilever support, even if a bending moment acts on the container, the bending reaction force in the membrane filter main body. The occurrence of
It is mechanically stable despite the existence of welding points between the elements.

However, in the above filter, one end of the liquid collection port of the main body of the membrane filter is closed, and the flow velocity in the liquid collection port becomes smaller toward the closed end. For example, when the filter is not used for a long period of time. Therefore, when the inside of the collection port is replaced with the storage solution, it takes a long time to replace the part near the blockage of the collection port where the flow velocity is low. Also, when cleaning the inside of the liquid collection port, the flow rate of the cleaning liquid in the liquid collection port decreases toward the closed end, and it is difficult to clean the vicinity of the closed end of the liquid collection port. Further, depending on the piping condition or installation space, it may be necessary to use the above filter upside down. In this case, the closed end of the liquid collection port of the membrane filter body will be on the upper side, so in the liquid collection port There is also a problem that the air cannot be completely expelled and the air is trapped at the upper end of the block of the collection port (if there is a space, there is an irrational condition such as the growth of bacteria).

An object of the present invention is to house the membrane filter body in a container having a stock solution inlet port at one end and a permeate outlet port at the other end, and the other end of the permeated water collecting port of the membrane filter body is described above. In a filter that is water-tightly connected to the permeate extraction port of the container, while ensuring the mechanical stability of the membrane filter body against the bending moment acting on the container, liquid replacement in the permeate collection port, It is an object of the present invention to provide a membrane filter in which washing and the like can be uniformly and easily performed and an air trap can be easily eliminated even when used upside down.

<Means for Solving the Problems> A filter according to the present invention has a membrane filter main body housed in a container having a raw water press-in port at one end and a permeate extraction port at the other end. In a filter in which the other end of the permeated water collection port is connected to the permeated water extraction port of the container in a watertight manner, a flexible tube is connected to one end of the permeated water collection port of the membrane filter body in a watertight manner, The flexible tube is drawn out of the container in a watertight manner.

<Description of Embodiments> Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The filter according to the present invention is a forward direction with respect to the vertical direction,
Although it can be used in any of the reverse directions, the reverse arrangement will be described for convenience of description.

FIG. 1 is a vertical sectional view showing an embodiment of the present invention. First
In the figure, reference numeral 1 is a main body of a membrane filter, which is provided with a permeated water collecting port 10 in the center. A indicates a unit, and permeate passage grooves are formed on both sides of the plastic disk type spacer 11.
12 is formed, and this passage groove is formed by the communication hole 13
A film 14 is attached to each surface of the spacer 11, and the inner and outer peripheral portions of each film are heat-welded (hereinafter simply referred to as welding) to the spacer. The membrane filter body 1 is constructed by stacking the units A and welding them together at the center of the spacer. 2 is a plastic end plate welded to the upper end of the permeate collection port 10. 3 is a flexible plastic tube welded to the end plate, and its flexural rigidity (EI) is 1/5 or less of EI of the membrane filter body. Reference numeral 4 denotes a container, which is made of plastic or metal and has a lower half piece and an upper half piece. Reference numeral 41 denotes a lower half piece, which has a permeated liquid outlet 411, and the mouth tube also protrudes inward. The lower end of the liquid collection port of the main body of the membrane filter is welded to the inner mouth pipe. The reference numeral 412 is an air vent when originally used in the upward direction, and is not necessary in the downward position shown in the drawing, and is therefore closed by the cap 413. 42 is the upper half of the container, and is provided with a stock solution press-fitting port 421 and a tube insertion tube portion 422,
After inserting the flexible tube 3 into the tube portion 422, the upper half piece 42 is bonded to the lower half piece 41 by packing and a port nut (not shown). Reference numeral 5 is a valve attached to a flexible tube.

To filter the stock solution with the above filter, press the stock solution injection port.
It is only necessary to press-fit from 421 into the container 4, and the membrane 1 of each unit A
The permeated water that has permeated 4 collects in the liquid collection port 10. In the initial stage, the valve 5 of the flexible tube 3 is left open, the permeated water is allowed to overflow from the tube 3, and after confirming that no bubbles are mixed in the overflow water, the valve 5 is closed and then the permeated water is passed. Permeate is taken out only from the water outlet 411. Therefore, it is possible to prevent air bubbles from being mixed into the extracted water, and to prevent an air trap at the liquid collecting port. Moreover, when the valve is opened, the permeated water also circulates to the upper end of the liquid collection port at a considerably high speed, so that contamination such as fine particles adhering to the upper end of the liquid collection port can be easily removed. Further, when the use of the filter is interrupted, the valve 5 is opened and the cleaning liquid is injected from the permeated water outlet 411, so that the inside of the liquid collection port 10 can be easily and uniformly cleaned. Also in the liquid replacement, if the valve 5 is opened and the replacement liquid is introduced from the permeated water extraction 411 and the residual permeated water in the liquid collection port 10 is extruded by this introduced liquid, the inside of the liquid collection port 10 can be easily and promptly. Can be replaced by liquid.

FIG. 2 shows another embodiment of the present invention, in which a joint 20 is welded to the upper end of the liquid collection port 10 of the membrane filter main body 1, and the tube 3 is attached to the joint by a seal ring (metal, Teflon) 6 and a nut 7. The flexible tube 3 is drawn out from the screw grooved mouth tube 422 in the center of the upper half of the container, and the mouth tube is sealed by the seal ring 6 and the nut 7. 421 is a stock solution pressure inlet.

In the above, the membrane permeation body is not limited to the stack type. For example, a pleat type in which the membrane is formed in a pleated shape to increase the membrane area can also be used.

The above filter can be used with the permeated liquid outlet facing upward and the raw liquid pressure inlet facing downward.In this case also, if the valve of the tube is opened and the replacement liquid is injected, the liquid collecting port can be used. The permeated water inside can be completely and quickly replaced with the replacement liquid. Further, the cleaning liquid can be made to go straight into the liquid collection port, and the cleaning can be completed completely and quickly.

<Effect of the Invention> As described above, in the filter according to the present invention, both ends of the liquid collection port in the main body of the membrane filter can be opened, so that the cleaning liquid can be passed from one end of the liquid collection port to the other end at high speed. Thus, cleaning of that port can be done quickly and easily. Further, by injecting the replacement liquid from one end of the liquid collection port, the residual permeated water in the port can be pushed out from the other end of the port, so that the inside of the port can be replaced with the replacement liquid easily and quickly. Also,
Even when used upside down, the upper end of the liquid collection port can be opened to let out the air in the liquid collection port at the initial stage of taking out the permeated liquid, so that the air trap at the upper end of the liquid collection port can be eliminated. Furthermore, since the tube connected to the membrane filter body is flexible and the bending rigidity is extremely small, even if external bending force acts on the filter, the bending deformation of the membrane filter body can be kept to a slight extent, so that the seal The main body of the membrane filter having many points can be maintained mechanically and stably.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of the present invention, FIG. 2 is an explanatory view showing an upper half of another embodiment of the present invention, and FIG. 3 is an explanatory view showing a conventional example. 1 ... Membrane filter body, 10 ... Permeated water collection port 3 ... Tube, 4 ... Container 411 ... Permeated liquid extraction port 421 ... Original liquid pressure injection port

Claims (1)

[Scope of utility model registration request] 1. A membrane filter body is housed in a container having a stock solution press-in port at one end and a permeated liquid take-out port at the other end, and the other end of the permeated water collecting port of the membrane filter body is connected to the container. In a filter that can be watertightly connected to the permeated liquid outlet, a flexible tube is connected to one end of the permeated water collection port of the membrane filter body in a watertight manner, and the flexible tube is drawn out of the container in a watertight manner. A membrane filter characterized by the following.