JPH0554371B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a hollow fiber membrane filtration device that aims to maintain the integrity of hollow fiber membranes and increase the effective membrane surface area, thereby improving the filtration effect.

[Technical Background of the Invention] Hollow fiber membranes are generally hollow fiber membranes with an outer diameter of about 0.3 to 3 mm and having minute holes, and can have a large cross-sectional area within a unit volume, and have good pressure resistance. Because of its excellent properties, it is widely used in the electronic industry, medicine, and wastewater treatment fields for ultrafiltration and reverse osmosis filters.

Therefore, a conventional filtration device using hollow fiber membranes will be explained with reference to FIGS. 3 and 4. Reference numeral 1 in the figure indicates a filtration container consisting of a filtration container body 1A and a container lid 1B.
is introduced and discharged via the filtered after-treatment liquid outlet nozzle 3. A plurality of hollow fiber membrane modules 4 are installed within the filtration container main body 1A.
That is, each hollow fiber membrane module 4 is fixed to a tube plate 6 via a module fixing part 5, and this tube plate 1 is connected to an upper flange 8 provided at the upper opening edge of the filtration container body 1A and a container lid 1B. It is fixed between the lower flange 7 provided at the lower end opening edge of. The module 4 has a plurality of hollow fiber membranes 4.
A is bundled to form a U-shape, and its ends are fixed with resin, and the portion fixed with this resin is the module fixing part 5. Note that the reference numeral 9 in the figure indicates a backwash water inlet nozzle. The source liquid A introduced into the filtration container body 1A is filtered when passing through the hollow fiber membrane, and the filtered treatment liquid flows above the tube plate 6 through the hollow portion of the hollow fiber membrane. Then, the processing liquid is transferred through the processing liquid outlet nozzle 3.

In the above configuration, the hollow fiber membrane has a property that it is difficult for air to pass through, so conventionally, a vent nozzle 11 was connected to the upper part of the filtration container main body 1A, and vent processing could be performed through the vent nozzle 11.

[Problems with Background Art] The above configuration has the following problems. That is, even when the above-mentioned venting process is performed, air remains in the upper part of the filtration container main body 1A, and the hollow fiber membrane module 4 in that part comes into contact with the air. If it came into contact with such air, there was a possibility that it would deteriorate due to the properties of the hollow fiber membrane. At the same time, the hollow fiber membrane module 4 located in the air does not contribute to filtration in any way, and there is also the problem that the effective membrane surface area is reduced.

Therefore, conventionally, as shown in FIG.
A method was adopted in which a vent nozzle 13 was attached to further process the remaining air. However, in the case of such a configuration, there is no problem when the number of hollow fiber membrane modules 4 is small, but when the number of hollow fiber membrane modules increases, it is necessary to take into account the discharge of air during backwashing. Although it is necessary to increase the diameter of the vent to that extent, there is a limit to the increase in the diameter of the second vent due to the thickness of the tube plate 6, and therefore there is a problem that sufficient venting cannot be performed.

[Object of the Invention] The present invention has been made based on the above points, and its purpose is to perform venting treatment reliably with a simple operation and to immerse the entire hollow fiber membrane module in the source liquid. It is an object of the present invention to provide a hollow fiber membrane filtration device capable of effectively increasing the effective membrane surface area.

[Summary of the Invention] That is, the present invention connects a vent pipe to the container-side open end of a vent nozzle provided in the filtration container main body, and provides the vent pipe with the open end facing and close to the lower surface of the tube plate. It is characterized by:

In other words, the upper end of the vent channel located in the filtration container main body of the vent mechanism is configured to be located above the lower end of the upper end fixing part of the hollow fiber membrane module, thereby achieving the desired venting process in one venting process. The entire hollow fiber membrane module is immersed in the source liquid.

[Embodiment of the Invention] A first embodiment of the invention will be described below with reference to FIG. Note that the same parts as in the prior art are denoted by the same reference numerals, and the explanation thereof will be omitted. Reference numeral 111 in the figure is a vent pipe connected to the open end of the vent nozzle 11 on the container side. It is located above the bottom edge of. With this configuration, the air layer 12 remaining after the venting treatment is reduced, and the entire hollow fiber membrane module 4 is immersed in the source solution A.

According to this embodiment, the following effects can be achieved.

(1) In other words, by performing the venting process, the liquid level of the stock solution A in the filtration container main body 1A reaches above the lower end of the fixing part 5 of the hollow fiber membrane module 4, so that the entire hollow fiber membrane module 4 is in the stock solution. It will be immersed in. Therefore, it is possible to solve the conventional problems such as the upper end of the hollow fiber membrane module 4 deteriorating due to contact with air, and the entire hollow fiber membrane module 4 can contribute to filtration. , the effective membrane area is expanded, allowing efficient filtration.

(2) In addition, the venting process in the example was performed only once;
There is no need for a second vent process using a second vent as in the past, and the work is easy.

Next, a second embodiment will be described with reference to FIG. Reference numeral 121 in the figure is a vent pipe, and the filtration container main body 1 is located at the attachment position of this vent pipe 121.
A weir plate 122 is installed inside the vent pipe 121, and a vent space 123 communicating with the vent pipe 121 is formed. The upper end of the weir plate 122 extends above the lower end of the fixing part 5 of the hollow fiber membrane module 4.

According to the above configuration, when venting is performed using the vent pipe 121 and the vent space 123, the liquid level of the source liquid A in the filtration container body 1 reaches the fixed part of the hollow fiber membrane module 4 as shown in the figure. It rises further above the lower end of 5. Therefore, the residual air layer 12 can be reduced, and the entire hollow fiber membrane module 4 can be immersed in the source solution A, and the same effects as in the first embodiment can be achieved. . Furthermore, in the case of this embodiment, when the hollow fiber membrane filtration device is large-sized and the diameter of the vent nozzle 121 is increased, the exclusive area of the vent nozzle 121 within the filtration container body 1 is smaller than that of the first embodiment. Since the configuration is smaller than that of the example, it is extremely effective.

[Effects of the Invention] As detailed above, according to the hollow fiber membrane filtration device of the present invention, it is possible to perform the desired venting treatment with one venting treatment and to immerse the entire hollow fiber membrane module in the source liquid. becomes. Therefore, it is possible to maintain the integrity of the hollow fiber membrane module, and since the effective membrane area is increased, it is possible to improve the filtration efficiency.

Furthermore, the present invention has a structure in which a vent pipe is connected to the open end of the vent nozzle on the container side, and the open end of the vent pipe is provided facing and close to the lower surface of the tube plate. Deterioration of the thread membrane can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view of a hollow fiber membrane filtration device showing a first embodiment of the present invention, FIG. 2 is a partial sectional view of a hollow fiber membrane filtration device showing a second embodiment, and FIG. 3 4 shows a conventional example, FIG. 3 is a sectional view of a hollow fiber membrane filtration device, and FIG. 4 is a sectional view of a part of the hollow fiber membrane filtration device. DESCRIPTION OF SYMBOLS 1... Filtration container main body, 4... Hollow fiber membrane module, 4A... Hollow fiber membrane, 5... Fixing part, 6... Tube plate, 7, 8... Flange, 111... Vent nozzle.

Claims (1)

[Claims] 1. A filtration container main body having an opening at the upper end, a stock solution inlet nozzle provided on the filtration container main body, a container lid that closes the upper end opening of the filtration container main body, and a processing liquid outlet nozzle provided on the container lid, A tube sheet provided between the container lid and the filtration container main body, a hollow fiber membrane module suspended from the tube sheet into the filtration container main body, and a vent nozzle provided in the filtration container main body. In the hollow fiber membrane filtration device, a vent pipe is connected to the container-side open end of the vent nozzle, and the open end of the vent pipe is provided opposite to and close to the lower surface of the tube plate. Membrane filtration device.