JPH0510966B2 - - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Field of Application) The present invention relates to a hollow fiber membrane filtration device applied to, for example, a filtration device in a nuclear power plant, and in particular to vibration suppression of a hollow fiber membrane module. The present invention relates to a hollow fiber membrane filtration device with improved effectiveness.

(Prior Art) In general, in nuclear power plants, generation of corrosion products is suppressed and removed as radiation reduction measures. For example, filtration devices are used to separate and remove suspended matter present in radioactive waste fluid generated in nuclear power plants or ascites in primary cooling systems. Conventionally, such filtration devices use pre-coated filters such as powdered ion exchange resin, flat membrane filters such as filter paper or filter cloth membrane filters, or hollow filters such as sintered metal or ceramic filters. Some of them used tube-type filters.

However, filtration devices that use powdered ion exchange resin generate a large amount of resin waste, and those that use flat membrane filters or hollow tube filters require a large circulation flow rate and are difficult to configure. This increased complexity, increased equipment costs, generated secondary waste, and caused problems such as low filtration efficiency.

Therefore, recently, in order to eliminate such problems, a hollow fiber membrane filtration device using a hollow fiber membrane filter has been developed. Hollow fiber membrane filter has an external shape
It is a hollow fiber membrane with a diameter of about 0.3 to 3 mm and has fine perforations in the peripheral wall.It can have a large cross-sectional area within a unit volume, and has excellent pressure resistance, so it is suitable for ultrafiltration and reverse filtration. It is widely used as a filter material for penetration in fields such as the electronic industry, medicine, and wastewater treatment.

9 to 13 show conventional examples of such hollow fiber membrane filtration devices. FIG. 9 shows the cross-sectional structure of the entire device. A tank-shaped container 1 is divided into upper and lower parts by a horizontal partition wall 3, with a lower space serving as a filtration chamber 1a and an upper space serving as a processing liquid chamber 1b. A plurality of hollow fiber membrane filters 2 are provided in the filtration chamber 1a, hanging down from the partition plate 3, and the hollow portion of each hollow fiber membrane filter 2 communicates with the processing liquid chamber 1b. The hollow fiber membrane filter 2 is made by bundling hollow fibers 2A and fixing the ends with fixing members 19 and 20 such as resin. This bundle is called a hollow fiber membrane module. The hollow fiber membrane filter 2 has an upper end fixing member 2
0 to the partition plate 3, and a plurality of them are connected vertically. (The fixed part of the middle part is shown below.
(referred to as connecting member 18). Note that 2D is a support pipe for supporting the hanging load of the hollow fiber membrane filter 2, and is provided in the center of the hollow fiber membrane module in connection with the hollow fiber membrane filter 2. A liquid supply pipe 4 communicating with the filtration chamber 1a is connected to the lower end of the container 1, and a processing liquid discharge pipe 5 communicating with the processing liquid chamber 1b is connected to the upper end. The liquid supplied into the filtration chamber 1a via the liquid supply pipe 4 is subjected to a filtration action when passing through the hollow fiber membrane filter 2,
It flows out into the processing liquid chamber 1b above the partition plate 3 through the hollow portion of each hollow fiber 2A, and is discharged via the processing liquid discharge pipe 5. Note that an on-off valve 6 is inserted into the liquid supply pipe 4. The supply pipe 4 also includes a concentrated liquid discharge pipe 7 for discharging the concentrated liquid after discharging the processing liquid.
are connected in a branched manner, and an on-off valve 8 is inserted into this concentrate discharge pipe 7.

When cleaning the hollow fiber membrane filter 2, pressurized gas for backwashing is supplied into the hollow portion of each hollow fiber 2A of the hollow fiber membrane filter 2 via the treatment liquid discharge pipe 5. Note that a bubbling tube 9 is installed below the hollow fiber membrane filter 2 in the container 1, and a bubble hole 10 is formed on the lower surface side of the bubbling tube 9. This bubbling pipe 9 is connected to an air supply pipe 11 having an on-off valve 12, and by supplying air to this bubbling pipe 9 via the air supply pipe 11, air bubbles are generated from the bubble hole 10, and the bubbles are generated. The cleaning efficiency is increased by bubbling the hollow fiber membrane filter 2 with air bubbles. Note that an overflow pipe 13 is connected below the attachment position of the partition plate 3. An on-off valve 14 is inserted into this overflow pipe 13.

By the way, in the configuration shown in FIG. 9, there is a possibility that the hollow fiber membrane filter 2 may swing or the air bubbles may not come into sufficient contact with each other during bubbling. Therefore, an improvement plan was made as shown in FIG. The overall configuration of this device is substantially the same as that shown in FIG. 9, so corresponding parts in the figure are denoted by the same reference numerals and redundant explanation will be omitted. In this example, in order to reduce the amplitude of the vibration of each hollow fiber membrane module and to efficiently introduce air bubbles into the hollow fiber membrane filter 2 during bubbling, a space is provided on the outer periphery of the hollow fiber membrane filter 2 for introducing air bubbles. A protective tube 16 is installed with its lower end and a portion of its upper end open.

However, in the device with the configuration shown in FIG.
I had the following problem. That is, while it is desired that the size of the container 1 of the hollow fiber membrane filtration device be made as compact as possible, it is also desired that the surface area of the hollow fibers be increased in order to increase the filtration flow rate. Therefore, it is conceivable to use a longer hollow fiber membrane filter or to use a plurality of hollow fiber membrane filters 2 connected in a plurality of stages. In addition, installing a large number of hollow fiber membrane filters 2 side by side in the horizontal direction requires more space due to the increased diameter of the container, so generally only the height is larger and the installation space is narrower in the vertical direction. Long compositions are often used. However, since the hollow fiber membrane filter 2 is often made of a plastic material with a low elastic modulus and strength, if the length is increased too much, fluid vibrations or vibrations during earthquakes may increase. For example, the 10th
In an experiment using the filtration device shown in the figure, vibrations of approximately 1 Hz were generated due to fluid vibrations in the water passing through the filtration. Furthermore, it has been confirmed that vibrations of about 5 Hz are applied during bubbling.

Generally, when a material is subjected to repeated forces, fatigue occurs, and as the number of repetitions increases, the fracture strength decreases. Even if the vibration is relatively small like the fluid vibration, the hollow fiber membrane filter 2 may be destroyed if the vibration is applied for a long period of time. Protection tube 15
Even in the case of a filtration device equipped with a hollow fiber membrane filter 2, as shown in the cross-sectional shape of FIG. A certain distance is provided between the protective tube 15 and the surrounding protective tube 15, but under such a configuration, as shown in FIG. 12,
The hollow fiber membrane filter 2 may vibrate greatly.

Note that the hollow fiber membrane filter needs to be replaced when it becomes clogged and backwashing becomes impossible, or when its useful life has expired due to material deterioration or the like. Therefore, the hollow fiber membrane filter 2 cannot be completely fixed to the container 1.

As described above, since vibrations are not sufficiently suppressed, conventionally there have been certain restrictions on increasing the length of the hollow fiber membrane filter 2 or increasing the number of stages.

Furthermore, in order to increase the capacity, when the hollow fiber membrane filter 2 is multi-staged as shown in FIG.
As shown in FIG. 13, the connecting member 18 and the lower end fixing member 19 obstruct the flow of air bubbles, and the air bubbles are not sufficiently supplied to the hollow fibers 2A near the connecting member 18 and the lower end fixing member 19 during bubbling. In some cases, suspended matter was not removed sufficiently.

(Problems to be Solved by the Invention) In conventional devices, protection tubes cannot always sufficiently prevent vibrations of the hollow fiber membrane module, and there are also areas where the bubbling effect is insufficient, leading to a shortened membrane life. There are problems such as.

The present invention was made in view of the above circumstances, and it is possible to sufficiently suppress the vibration of the hollow fiber membrane filter, thereby increasing the length of the hollow fiber membrane filter and the number of connected hollow fiber membrane filters, and further improving the backwashing effect. get enough,
The present invention aims to provide a hollow fiber membrane filtration device that can extend the life of the membrane.

[Structure of the invention]

(Means for Solving the Problems) The hollow fiber membrane filtration device according to the present invention has a container in which a filtration chamber that communicates with a liquid supply pipe and a processing liquid chamber that communicates with a processing liquid discharge pipe are partitioned, A plurality of hollow fiber membrane modules are installed vertically in this filtration chamber, and the hollow part of each hollow fiber membrane filter of each hollow fiber membrane module is communicated with the processing liquid chamber, and each hollow fiber membrane module is connected with a protection tube. The hollow fiber membrane filtration device is an enclosed hollow fiber membrane filtration device, in which each hollow fiber membrane module has a plurality of elements divided in the axial direction connected to each other by a connecting member, and the lower end of the lowest filter element is connected by a fixing member. In the case where the protective tube is bound and fixed, a plurality of protrusions for suppressing vibration of the hollow fiber membrane module are provided at a constant interval in the circumferential direction of the protective tube on the inner surface side of the protective tube at least in a portion surrounding the connecting member and the fixing member. It is characterized by being open and protruding along the axial direction.

(Function) According to the present invention, a plurality of protrusions for suppressing vibration of the hollow fiber membrane module are provided on the inner surface side of the protective tube at least in a portion surrounding the connecting member and the fixing member, so that the hollow fiber membrane module can be When vibrating, it is supported in contact with the protrusions, and large displacements such as contacting the inner surface of the protection tube do not occur, so vibrations are effectively suppressed.
At that time, the opposing protrusion contact portions are the connecting member at the intermediate portion in the axial direction of the module and the fixing member at the lower end,
Since the hollow fiber membrane itself does not come into contact with the protrusions, the degree of fatigue of the hollow fiber material can be suppressed to an extremely low level.

In addition, since the protrusions are provided at regular intervals in the circumferential direction of the protective tube and protrude along the axial direction, even when the protrusions are in contact with the protrusions of the hollow fiber membrane module, they do not touch the outer peripheral surface of the module. There is always a gap along the axial direction between it and the inner surface of the protective tube, so the passage of liquid, the rise of air bubbles, and the fall of exfoliated solids from the hollow fiber membrane filter are not impeded in any way. Therefore, filtration, air scrubbing, backwashing, etc. are performed extremely smoothly. As a result, the membrane life is extended, and it becomes possible to increase the length of the hollow fiber membrane filter by increasing the number of stages.

(Example) Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 7. In addition, the same reference numerals as in FIGS. 9 to 13 will be used to describe the same components as in the prior art.

FIG. 1 shows the cross-sectional configuration of the entire device.

A tank-shaped container 1 is divided into upper and lower parts by a horizontal partition wall 3, with a lower space serving as a filtration chamber 1a and an upper space serving as a processing liquid chamber 1b. A plurality of hollow fiber membrane filters 2 are provided in the filtration chamber 1a, hanging down from the partition plate 3, and the hollow portion of each hollow fiber membrane filter 2 communicates with the processing liquid chamber 1b.

The hollow fiber membrane filter 2 is made by bundling hollow fibers 2A and fixing the ends with fixing members 19 and 20 such as resin. This bundle is called a hollow fiber membrane module. The hollow fiber membrane filter 2 is attached to the partition plate 3 via the upper end fixing member 20, and a plurality of elements divided into upper and lower parts are attached to the header-shaped connecting member 1.
8, the structure is such that they are vertically connected. Note that 2D is a support pipe for supporting the hanging load of the hollow fiber membrane filter 2, and is provided in the center of the hollow fiber membrane module in connection with the hollow fiber membrane filter 2.

A liquid supply pipe 4 communicating with the filtration chamber 1a is connected to the lower end of the container 1, and a processing liquid discharge pipe 5 communicating with the processing liquid chamber 1b is connected to the upper end. The liquid supplied into the filtration chamber 1a via the liquid supply pipe 4 is subjected to a filtration action when passing through the hollow fiber membrane filter 2, and is processed through the hollow portion of each hollow fiber 2A above the partition plate 3. It flows out into the liquid chamber 1b and is discharged via the processing liquid discharge pipe 5.

Note that an on-off valve 6 is inserted into the liquid supply pipe 4. Further, a concentrated liquid discharge pipe 7 for discharging the concentrated liquid after discharging the processing liquid is branched and connected to the supply pipe 4, and an on-off valve 8 is inserted in this concentrated liquid discharge pipe 7.

When cleaning the hollow fiber membrane filter 2, pressurized gas for backwashing is supplied into the hollow portion of each hollow fiber 2A of the hollow fiber membrane filter 2 via the treatment liquid discharge pipe 5. Note that a bubbling tube 9 is installed below the hollow fiber membrane filter 2 in the container 1, and a bubble hole 10 is formed on the lower surface side of the bubbling tube 9. This bubbling pipe 9 is connected to an air supply pipe 11 having an on-off valve 12, and by supplying air to this bubbling pipe 9 through the air supply pipe 11, air bubbles are generated from the bubble hole 10, and the air bubbles are generated from the bubble hole 10. The cleaning efficiency is increased by bubbling the hollow fiber membrane filter 2 with air bubbles. Note that an overflow pipe 13 is connected below the attachment position of the partition plate 3. An on-off valve 14 is inserted into this overflow pipe 13. and,
In order to efficiently introduce air bubbles into the hollow fiber membrane filter 2 during bubbling, a protection tube 16 is installed around the outer periphery of the hollow fiber membrane filter 2 with an interval for introducing air bubbles and whose lower end and upper part are open. It is said that

By the way, in this embodiment, eight inward protrusions 17 are provided on the protective tube 16 at portions that may come into contact with the connecting member 18 and the tip 19 of the hollow fiber membrane filter 2. . A cross section of this part is shown in FIG. Note that the protrusion 17 is provided by deforming the protective tube 16 inward.
In this case, the inner diameter of the protective tube 16 needs to be such that it does not obstruct the passage of liquid during filtration, and that air bubbles are sufficiently supplied to the hollow fibers during bubbling. According to the inventor's study, it was found that it is desirable to set the dimensions as shown in the following equation (1), taking into consideration the distance between the protective tube 16 and the hollow fiber membrane module.

√ ₂ + ₁ ² > d ₂ √ ₁ × ₃ ² ... (1) Here, d ₁ is the outer diameter of the hollow fiber assembly of the part of the hollow fiber membrane filter that fixes the hollow fibers, d ₂ is the inner diameter of the protective tube,
d ₃ is the outer diameter of the connecting member 18, and Q is the rated flow rate per protection tube. C ₁ and C ₂ are constants, and it has been found through experiments that it is desirable to set C ₁ =7.0×10 ² and C ₂ =1.5×10 ⁴ .

In addition, although the protrusions 17 are provided at eight locations at 45-degree intervals as shown in FIGS. 2 and 3, they may also be provided at four locations at 90-degree intervals as shown in FIGS. 4 and 5. good. Note that the number of protrusions 17 is not limited to eight or four, and can be selected from various locations within the range of four to eight from the viewpoint of vibration suppression effect, backwashing effect, and the like. That is, FIG. 6 shows the relationship between the number of protrusions, the hollow fiber membrane filter amplitude, and the flow path area. FIG. 6a is a graph showing the above relationship, and FIG. 6b is an explanatory diagram showing the concept of flow path area, etc. 6th
As shown by the white circles in Figure a, the amplitude σ of the hollow fiber membrane filter decreases rapidly when the number n of ridges increases from 1 to 8, but even if the number n increases beyond that, the amplitude σ does not decrease much, and the improvement in the vibration suppression effect is small.

On the other hand, as shown by the black circles in FIG. 6, the flow channel cross-sectional area A-Ad decreases monotonically as the number n of protrusions increases, and the pressure loss within the flow channel gradually increases. Therefore, if both the vibration suppression effect and the flow path cross-sectional area are taken into consideration, the practically appropriate number n of protrusions is 4 to 4.
It is thought that there are 8 pieces.

The data shown in FIG. 6 was obtained under the following conditions.

[Protrusion height H = 7.8 mm Protective pipe inner diameter d ₂ = 130 mm Connecting member outer diameter d ₃ = 108 mm Cross-sectional area reduction A _d = 37.8 mm ² /piece] Regarding the height of the protrusion 17, A lower value is desirable from the viewpoint of ease of replacing the hollow fiber membrane filter 2, but a higher value is desirable from the viewpoint of vibration suppression and bubbling effect, so a value suitable for the actual machine is selected.
In addition, from the viewpoint of vibration suppression, when considering the height H of the protrusion, a desirable range can be determined from the following formula (2).

Here, E is the Young's modulus of the material constituting the hollow fiber membrane filter, I is its moment of inertia, Z is its section modulus, n is the number of protrusions, l is the length of one stage of the hollow fiber membrane filter, d ₂ is the inner diameter of the protective tube, d ₃ is the outer diameter of the connecting member, and σ _C is the fatigue limit (tolerable value) of the hollow fiber membrane filter. That is, the left side of the above equation (2) represents the stress that acts on the hollow fiber membrane filter due to vibration, and the height H of the protrusion is determined so that this stress is equal to or less than the fatigue limit shown on the right side.

Next, the action will be explained.

First, the stock solution supplied into the container 1 via the liquid supply pipe 4 permeates inside each hollow fiber 2A of the hollow fiber membrane filter 2, and is filtered at that time. The filtered processing liquid flows out above the partition plate 3 through the hollow portion of the hollow fiber 2A, and is further discharged via the processing liquid discharge pipe 5. Then, the stock solution is continuously supplied into the container 1 through the liquid supply pipe 4 at a constant pressure or a constant flow rate, and filtration is continued until the filtration differential pressure of the hollow fiber membrane filter 2 reaches a preset value.

Now, during this filtration operation, the flow of fluid is
Since the hollow fiber membrane filter 2 is located inside, vibration of the hollow fiber membrane filter 2 occurs. This vibration becomes more intense when the hollow fiber membrane filter is made longer or multistage. However, according to the above configuration, since the protrusion 17 is provided inside the protective tube 16, the vibration of the hollow fiber membrane filter 2 is restricted and damped. This effect is shown in FIG. As shown in FIG. 3, the state in which the hollow fiber membrane filter 2 is in contact with the two protrusions 17 is the case where the vibration is at the maximum amplitude. When the hollow fiber membrane filter 2 vibrates from a predetermined position due to fluid vibration, it comes into contact with any of the eight protrusions 17, so that vibration in any direction is restricted. In this way, as a result of reliably suppressing the vibration of the hollow fiber membrane filter 2, it becomes easy to increase the length of the hollow fiber membrane filter and to connect it in multiple stages. However, even in this case, the flow path within the protection tube 16 is not blocked, and liquid flow etc. are not obstructed in any way.

Once a predetermined filtration differential pressure is reached, the filtration operation is stopped. Then, the hollow fiber membrane filter 2 is backwashed. This backwashing is performed by the reverse route to the above filtration. That is, the hollow fiber membrane filter 2 is supplied from a gas supply source (not shown) via the treatment liquid discharge pipe 5.
Water or air is pumped inside. Solid matter adhering to the outer surface of the hollow fiber membrane filter 2 is removed by pumping water or air, but at this time, air bubbles are generated from the micropores formed on the outside of the hollow fiber membrane filter 2. Therefore, the backwashing effect is enhanced. Further, in synchronization with such backwashing operation, a bubbling operation using air bubbles from the bubbling pipe 9 is performed. Bubbles generated from the bubbling tube 9 are introduced into the protective tube 16 from the lower end thereof, and are supplied to each hollow fiber membrane filter 2 . As described above, together with the backwashing effect, solid matter is effectively peeled off from the surface of the hollow fiber membrane filter 2. During this bubbling, the entire hollow fiber membrane filter 2 conventionally vibrates greatly as the bubbles rise, but in the above embodiment, the vibration is effectively caused by the action of the protrusions 17, as in the case of the filtration operation. is suppressed. Furthermore, since the cross-sectional area of the flow path is reduced at the protrusion 17, when bubbles pass through, the bubbles are finely separated. Then, when the bubbles are accelerated and pass through the connecting member 18 or the lower end fixing member 19, a spiral flow is generated in this portion as shown in FIG. Due to this swirling flow, air bubbles are sufficiently supplied to the hollow fibers 2A near the connecting member 18 or the lower end fixing member 19, to which bubbles have been difficult to be supplied conventionally, and the backwashing effect is improved. Further, the separated solid matter falls through the gap between the hollow fiber membrane filter 2 and the protection tube 16. At this time, if the upper and lower ends of the protrusion 17 are sloped, the falling of the solids will not be hindered and there will be less resistance when the liquid passes.

Due to such a backwashing effect, the hollow fiber membrane filter 2 is regenerated and used for the next filtration, and the same filtration action as described above is repeated again.

According to the above embodiment, the following effects are achieved.

(1) Since the protrusion 17 is provided inside the protection tube 16,
Fluid vibrations during filtration operations and vibrations caused by air bubbles during bubbling can be effectively suppressed. Note that the stress σ generated in the hollow fiber membrane filter 2 due to vibration
is maximum near the attachment point to the partition plate 3, and can be approximately expressed by the following equation.

σ=4EI/l ² ZW Here, E, I, W, l, and Z are the Young's modulus of the material constituting the hollow fiber membrane filter 2, respectively;
These are the moment of inertia of area, amount of deflection at the tip, length, and section modulus. The above equation was derived based on the assumption that a uniform force acts on the hollow fiber membrane filter 2 in the length direction. In the above formula, E, I, l, Z
Since is a constant value once the structure and material are determined, the following equation can be derived.

σ∝W That is, the stress acting on the hollow fiber membrane filter 2 is proportional to the amount of deflection W at the tip. Therefore, the amount of deflection W is reduced by the protrusions 17, and the stress on the hollow fiber membrane filter 2 is reduced, so that the length of the hollow fiber membrane filter 2 can be increased or the number of stages can be increased. It is possible to increase the capacity of the filter without increasing the diameter of the filter.

(2) Since sufficient air bubbles are also supplied to the hollow fibers 2A in the vicinity of the connecting member 18 of the hollow fiber membrane filter 2, the backwashing effect is improved.

In particular, by providing a plurality of protrusions 17 for suppressing vibration of the hollow fiber membrane module on the inner surface side of the protection tube 16 at least in a region surrounding the connecting member 18 and the fixing member 19, the hollow fiber membrane module can be prevented from bumping when vibrating. Vibration is effectively suppressed because it is supported in contact with the protrusion 17 and does not undergo large displacement such as contacting the inner surface of the protection tube 16. At this time, the contact portion of the protrusion against the protrusion is the connecting member at the intermediate portion in the axial direction of the module. 18 and a fixing member 19 at the lower end, and since the hollow fiber membrane itself does not contact the protrusion 17, the degree of fatigue of the hollow fiber material can be suppressed to an extremely low level.

In addition, since the protrusions 17 are provided at regular intervals in the circumferential direction of the protective tube 16 and protrude along the axial direction, even when the hollow fiber membrane module is in contact with the protrusions, the outer periphery of the module Surface and protection tube 1
There is always a gap along the axial direction between the hollow fiber membrane filter and the inner surface of the hollow fiber membrane filter. , filtration, air scrubbing, backwashing, etc. are performed extremely smoothly. As a result, the membrane life is extended, and it becomes possible to increase the length of the hollow fiber membrane filter by increasing the number of stages.

In the embodiment described above, the protrusion 17 was provided on a part of the protection tube 16, but the present invention is not limited to such a structure.As shown in FIG. It is also possible to adopt a configuration in which a section 17 is provided.

Even with such a configuration, it is possible to obtain substantially the same effects as in the embodiment described above, and since the protrusions 17 are continuous, there is no catch when replacing the hollow fiber membrane filter 2. It has the advantage of being easily replaceable. In addition, since the falling of solid matter from above is not obstructed at all, cleaning can be carried out effectively.

In each of the above embodiments, the protrusion 17 of the protective tube 16 is formed by deforming the protective tube 16 itself inwardly, but it is also possible to weld an object such as a round bar or a square rod inside the protective tube 16. It may also be configured to be attached by adhesive, screwing, or the like.

〔Effect of the invention〕

As described in detail above, according to the hollow fiber membrane filtration device according to the present invention, a plurality of protrusions for vibration suppression are provided at a certain distance in the circumferential direction of the protection tube in the area surrounding the module connecting member and the fixing member in the protection tube. By protruding along the axial direction at intervals, the multi-stage hollow fiber membrane module supports the non-hollow fiber portion of the module during filtration and backwashing, effectively suppressing vibrations. Excellent effects such as prolonging the life span and making it possible to realize a long hollow fiber membrane module are achieved.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view showing an embodiment of the present invention, Fig. 2 is a cross-sectional view showing an enlarged part of Fig. 1, and Fig. 3 shows the displacement of the hollow fiber membrane filter shown in Fig. 2. The cross-sectional views shown in FIGS. 4 and 5 are views corresponding to FIGS. 2 and 3 showing modified examples of the protrusion, and FIGS.
b is an explanatory diagram regarding the installation of the number of protrusions, FIG. 7 is a longitudinal sectional view illustrating the bubbling effect, FIG. 8 is a longitudinal sectional view showing another embodiment of the present invention, and FIGS. 9 and 10.
The figures are longitudinal cross-sectional views showing different conventional examples.
1 and 12 are cross-sectional views for explaining the conventional vibration effect, and FIG. 13 is a vertical cross-sectional view for explaining the conventional bubbling effect. 1... Container, 2... Hollow fiber membrane filter, 16...
...Protection tube, 17... Projection, 18... Connection member, 1
9... Fixed member.

Claims (1)

[Claims] 1. A filtration chamber communicating with a liquid supply pipe and a processing liquid chamber communicating with a processing liquid discharge pipe are defined in a container, and a plurality of hollow fiber membrane modules are vertically disposed within the filtration chamber. and a hollow fiber membrane filtration device in which a hollow portion of each hollow fiber membrane filter of each hollow fiber membrane module is communicated with the processing liquid chamber, and each of the hollow fiber membrane modules is surrounded by a protective tube, A hollow fiber membrane module is a hollow fiber membrane module in which a plurality of elements each divided in the axial direction are connected to each other by a connecting member, and the lower end of the lowest filter element is bound and fixed by a fixing member. A plurality of protrusions for suppressing vibration of the hollow fiber membrane module are provided at a portion surrounding the connecting member and the fixing member at regular intervals in the circumferential direction of the protective tube and protrude along the axial direction. Hollow fiber membrane filtration equipment. 2 The protrusions are arranged on the inner surface of the protection tube at equal intervals in the circumferential direction.
The hollow fiber membrane filtration device according to claim 1, wherein eight hollow fiber membrane filtration devices are provided. 3. The hollow fiber membrane filtration device according to claim 1, wherein a bubbling tube is provided in the container below the protective tube.