JPH08267065A - Membrane separation device - Google Patents

Abstract

PURPOSE: To provide a membrane separation device capable of keeping the treating efficiency over a long period of time. CONSTITUTION: In this device, plural separation membrane elements 21 arranged at an inside of a raw water tank 11 in which a raw water 1 to be treated is charged and divided into an inside and an outside with a membrane and a vacuum pump 24 connected to these elements 21 are provided. Membrane surface washing devices 26 which is provided respectively at lower ends of passages 22 provided between adjacent separation membrane elements 21 and in which plural diffuser port facing to the separation membrane element 21 side and a blower 28 connected to the membrane surface washing device are provided. In this way, a sticking of a solid matter to the separation membrane elements 21 accompanied with a treatment of the raw water 1 to be treated is suppressed.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a membrane separation device.

[0002]

2. Description of the Related Art When treating sewage, night soil, industrial wastewater, etc., or when purifying clean water or producing pure water used in semiconductor manufacturing, a membrane separation device for separating solid matter from treated raw water is used. Used. An example of treating human waste and the like with such a membrane separation device will be described with reference to FIG.

As shown in FIG. 6, treated raw water 1 such as human waste
A separation membrane module 50 is provided at the upper part of the inside of the raw water tank 11 in which the water is put. In this separation membrane module 50, the separation membrane elements 51 are arranged side by side and fixed by a fixing frame 53 so as to form a flow path 52 between a plurality of separation membrane elements 51 for separating solid matter from the treated raw water 1. is there. A vacuum pump 54 provided outside the raw water tank 11 is connected to each separation membrane element 51 via a pipe 55. An air diffuser 60 is provided near the bottom inside the raw water tank 11 so as to be located below the separation membrane module 50.
An aeration blower 61 provided outside the raw water tank 11 is connected to the diffused gas 50 via a pipe 62.

In such a membrane separator, the vacuum pump 5
4 is operated to reduce the pressure inside the separation membrane element 51, thereby separating the solid matter of the treated raw water 1 in the flow path 52 and taking in the treated raw water 1 into the separation membrane element 51 for treatment. . Further, by operating the aeration blower 61 and sending out air from the air diffuser 60 while diffusing it, oxygen is easily dissolved in the treated raw water 1 to maintain the dissolved oxygen concentration in the treated raw water 1, while the air diffuser is used. 60
The ascending flow generated by the rise of the air from the above flows through the flow path 52, and suppresses the adhesion of the solid matter to the surface of the separation membrane element 51 due to the separation of the solid matter, and prevents the separation ability of the separation membrane element 51 from decreasing. ing.

[0005]

However, in the membrane separation device as described above, the air from the air diffuser 60 is
As it rises while spreading from the bottom of the raw water tank 11,
The ascending flow not only tends to vary from channel to channel 52, but also tends to vary between the separation membrane side and the center side of the channel 52, that is, tends to stay near the separation membrane side of the channel 52. For this reason, the upward flow suppression force against the adherence of solids to the surface of the separation membrane element 51 is likely to be weak, and the membrane permeation flux (hereinafter referred to as flux) of the treated raw water 1 that permeates the separation membrane of the separation membrane element 51. Was difficult to stabilize, and the processing efficiency of the device was likely to decrease.

From the above, it is conceivable to solve the above-mentioned inconvenience by increasing the capacity of the aeration blower 61. However, in such a means, the processing capacity of the apparatus is relatively small. The aeration blower becomes very large, which not only considerably increases the space for installing the device, but also significantly increases the installation cost and the processing cost. For this reason, the separation membrane module 50 is taken out of the raw water tank 11 and separated.
The surface of No. 1 had to be frequently washed with a brush or the like, which placed a great burden on the operator.

[0007]

Means for Solving the Problems In order to solve the above-mentioned problems, a membrane separation apparatus according to the present invention is arranged inside a raw water tank in which treated raw water is placed, and the inside and outside are separated by a separation membrane. In a membrane separation device comprising a separation membrane element and a suction means that is connected to the separation membrane element and sucks the inside of the separation membrane element, the separation membrane element is provided near the lower end of the separation membrane element. And a feed unit that is connected to the jet nozzle and that jets fluid from the jet port of the jet nozzle.

The membrane separation apparatus according to the present invention is characterized in that the feeding means is a pressure water feeding means for jetting pressure water from the jet port of the jet nozzle.

[0009]

According to the membrane separation apparatus of the present invention constructed as described above, the inside of the separation membrane element is sucked by the suction means, so that the treated raw water is separated from the solid matter by the separation membrane. It is processed by being taken in. At the time of this treatment, the fluid is ejected from the ejection port of the ejection nozzle toward the separation membrane by the feeding means, and an upward flow is generated near the surface of the separation membrane. Adhesion of solid matter is suppressed.

Further, if the feed means is the pressure water feed means as described above, the upward flow generated near the surface of the separation membrane becomes more vigorous, so that the solid matter to the separation membrane due to the treatment of the treated raw water is increased. Is more reliably suppressed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment for treating human waste and the like with the membrane separation apparatus according to the present invention will be described with reference to FIGS. 1 is a schematic structural view thereof, FIG. 2 is a sectional view showing the structure of its main members, FIG. 3 is a side sectional view of a separation membrane element, and FIG. 4 is a sectional view taken along line IV-IV of FIG. FIG. 4 is a partially cutaway view of FIG.

As shown in FIG. 1, treated raw water 1 such as human waste
A separation membrane module 20 is provided in the upper part of the inside of the raw water tank 11 in which the separation membrane module 20 is placed. In this separation membrane module 20, the separation membrane elements 21 are arranged side by side and fixed by a fixing frame 23 so as to form channels 22 through which the treated raw water 1 passes between the plurality of separation membrane elements 21. In the separation membrane element 21, as shown in FIGS. 3 and 4, an element frame 21b is provided on the periphery of a spacer 21a, and separation membranes 21c are attached to both sides of the element frame 21b so as to laminate the spacer 21a. . That is, the separation membrane element 21 is divided into the inside and the outside by the separation membrane 21c. A pipe 25 is connected to the separation membrane element 21, and as shown in FIG.
A vacuum pump 24, which is a suction means provided outside the raw water tank 11, is connected.

That is, by operating the vacuum pump 24, the inside of the separation membrane element 21 is decompressed, and the raw raw water 1 in the flow path 22 is separated from the solid matter by the separation membrane 21c while the inside of the separation membrane element 21 is separated. Is taken into.

On the other hand, as shown in FIG. 1, an air diffuser 30 is provided near the bottom of the raw water tank 11 to separate the membrane module 2.
It is provided so as to be located below 0. An aeration blower 31 provided outside the raw water tank 11 is connected to the air diffuser 30 via a pipe 32. That is, by operating the aeration blower 31, the air is diffused and sent out from the air diffuser 30.

As shown in FIG. 1, the separation membrane module 20.
A film surface cleaning device 26, which is an injection nozzle, is provided at the lower end of each of the flow paths 22. As shown in FIG. 2, each of the membrane surface cleaning devices 26 has a plurality of air diffuser ports 26a, which are injection ports, formed on the upper side of the peripheral surface thereof, and these air diffuser ports 26a separate the adjacent separation membrane elements 21 from each other. Membrane 2
It is directed to 1c. As shown in FIG. 1, a pipe 27 is connected to the lower part of the membrane surface cleaning device 26, and a blast blower 28, which is a feeding means provided outside the raw water tank 11, is connected to the pipe 27. There is.

That is, by operating the air blower 28, air, which is a fluid, is jetted from each diffuser port 26a of each membrane surface cleaning device 26 toward the separation membrane 21c. As a result, an ascending flow is evenly generated in each flow path 22 of the separation membrane module 20, and the ascending flow has a velocity near the separation membrane 21c. Further, a discharge pump (not shown) is connected below the raw water tank 11, and the solid matter accumulated in the raw water tank 11 can be discharged to the outside by operating the pump.

In such a membrane separator, the vacuum pump 2
4 is operated to reduce the pressure in the separation membrane element 21, and the solid raw material 1 of the treated raw water 1 in the flow path 22 is separated by the separation membrane 21c and the treated raw water 1 is taken into the inside of the separation membrane element 21 for treatment. While performing aeration blower 31
Is operated to send out air from the air diffuser 30 while diffusing it, whereby oxygen is easily dissolved in the treated raw water 1 and the dissolved oxygen concentration in the treated raw water 1 is maintained.

In addition to performing the above-mentioned processing, the blower blower 2
8 is actuated to inject air from each air diffuser 26a of each membrane surface cleaning device 26 toward the separation membrane 21c, thereby uniformly generating an upward flow in each flow path 22 of the separation membrane module 20, and Separation membrane 2 of flow path 22
Directly act on the surface of 1c. As a result, the adhesion of solids to the surface of each separation membrane 21c due to the above-mentioned treatment is suppressed, and the separation ability of the separation membrane element 21 is prevented from being lowered. Therefore, the stability of the flux is improved, and the processing efficiency of the device can be maintained for a long time.

Therefore, it is not necessary to increase the capacity of the aeration blower 31, and a sufficient capacity can be obtained with a capacity suitable for the processing capacity of the apparatus, so that the space for installing the apparatus can be greatly increased. The cost can be reduced, and the installation cost and the processing cost can be significantly reduced.

Further, the membrane surface cleaning device 26 is installed at the lower end of each flow path of the separation membrane module 20, that is, the location where the upward flow is generated and the separation membrane 21c are brought close to each other, and the membrane surface cleaning device 2 is provided.
Since 6 is located at a shallow depth, the blower blower 28
Does not need to increase the injection pressure of the air to be ejected from the film surface cleaning device 26, and can sufficiently perform cleaning even with a relatively small capacity, which increases the space and cost for installing the blower blower 28. The rise can be minimized.

Therefore, the frequency of taking out the separation membrane module 20 from the raw water tank 11 and cleaning the surface of the separation membrane 21c with a brush or the like can be greatly reduced, and the burden on the operator can be greatly reduced. it can.

A second embodiment for treating human waste and the like with the membrane separation device according to the present invention will be described with reference to FIG. Note that FIG. 5 is a schematic structural diagram thereof. However, for the same members as those in the above-described embodiment, the same reference numerals as those in the above-described embodiment are used, and the description thereof will be omitted.

As shown in FIG. 5, the separation membrane module 20.
Jet nozzles 46, which are jet nozzles, are provided at the lower ends of the respective flow paths 22 of the above, and these jet nozzles 46 are piped to a jet pump 48 that is a pressure water supply means provided outside the raw water tank 11. The pressure water is jetted from each jet port of the jet nozzle 46 toward the separation membrane by operating the jet pump 48. That is, in the above-described embodiment, the air is jetted toward the separation membrane, whereas in the present embodiment, the pressure water is jetted toward the separation membrane.

In such a membrane separation apparatus, by using the same method as in the above-mentioned embodiment, the upward flow generated near the surface of the separation membrane can be made more vigorous than that in the above-mentioned embodiment, so that the separation can be performed. Adhesion of solid matter to the film can be suppressed more reliably than in the above-described examples. Therefore, the frequency of the cleaning work performed by taking out the separation membrane module 20 from the raw water tank 11 can be further reduced as compared with the above-described embodiment, and the burden on the worker can be further reduced.

In the above-described embodiment, the case of treating human waste and the like has been described, but the present invention is also applicable to the case of treating sewage or industrial wastewater, purification of clean water or production of pure water. be able to. When applied to such other uses, the separation membrane may be selected according to the properties of the treated raw water to be separated.

[0026]

In the membrane separation device according to the present invention, the fluid is ejected from the ejection port of the ejection nozzle toward the separation membrane by the feeding means to generate an upward flow near the surface of the separation membrane.
Since it is possible to prevent the solid matter from adhering to the surface of the separation membrane due to the treatment of the treated raw water, the stability of the flux can be improved and the efficiency of the treatment can be maintained for a long period of time. Therefore, the frequency of taking out the separation membrane element from the raw water tank and cleaning the surface of the separation membrane can be significantly reduced, and the burden on the operator can be significantly reduced.

Further, if the feed means is the pressure water feed means as described above, the upward flow generated near the surface of the separation membrane can be further energized. It is possible to more reliably suppress the adhesion of solid matter to the. Therefore, the frequency of cleaning described above can be further reduced, and the burden on the operator can be further reduced.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a first embodiment when treating human waste or the like with a membrane separation device according to the present invention.

FIG. 2 is a sectional view showing a structure of a main member thereof.

FIG. 3 is a side sectional view of a separation membrane element.

4 is a partially cutaway view of a cross section taken along line IV-IV of FIG.

FIG. 5 is a schematic configuration diagram of a second embodiment when treating human waste or the like with the membrane separation device according to the present invention.

FIG. 6 is a schematic configuration diagram of an example of a conventional membrane separation device that processes human waste and the like.

[Explanation of symbols]

 1 Treated Raw Water 11 Raw Water Tank 20 Separation Membrane Module 21 Separation Membrane Element 21c Separation Membrane 22 Flow Path 23 Fixed Frame 24 Vacuum Pump 26 Membrane Cleaning Device 26a Air Diffuser 28 Blower Blower 30 Air Diffuser 31 Aeration Blower 46 Jet Nozzle 48 Jet pump

Claims (2)

[Claims] 1. A separation membrane element, which is arranged inside a raw water tank in which treated raw water is placed and whose inside and outside are separated by a separation membrane, and which is connected to the separation membrane element and sucks the inside of the separation membrane element. In a membrane separation device comprising a suction means for performing, a jet nozzle provided in the vicinity of a lower end portion of the separation membrane element, the jet nozzle having a jet port directed to the separation membrane of the separation membrane element, and connected to the jet nozzle, A membrane separation device comprising: a supply unit configured to eject a fluid from the ejection port of the ejection nozzle. 2. The membrane separation device according to claim 1, wherein the feed means is a pressure water feed means for jetting pressure water from the jet port of the jet nozzle.