JPH11137914A - Filter tower using filament bundles - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform the removal of suspended matter on backwashing, and, particularly, to perform the removal of suspended matter in the filament bundle lower end part more effectively than before. SOLUTION: In this filter tower using filament bundles, in each of appropriate hole parts 3a of a perforated plate 3 arranged in the tower body, a hollow support nozzle 4 having an upper inflow and outflow port 42h functioning as an filtrate inflow part and a backwashing fluid outflow part and a lower inflow and outflow port 41d functioning as a backwashing fluid inflow part and a filtrate outflow part in the upper and lower positions between which the perforated plate 3 forms the boundary respectively is arranged. Filament bundles 5 each are arranged with their lower end parts 5a being fixed in the positions above the perforated plate 3 at the support nozzles 4. In each of other hole parts 3a of the perforated plate 3, a hollow backwashing nozzle 6 having an upper opening 61e functioning as a backwashing fluid outflow part only and a lower opening 61d functioning as a backwashing fluid inflow part only in the upper and lower positions between which the perforated plate 3 forms the boundary respectively and the upper end of which nozzle 6 is closed is arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to tap water for industrial works, sewage, river water, lake water, coagulated sedimentation supernatant water, intermediate water for various processes, various recovered waters such as recovered water in papermaking processes, various wastewaters, and biological materials. The present invention relates to a filtration tower using a long fiber bundle for removing a suspension in a stock solution such as treated water of a treatment device, a valuables-containing liquid, sake or oil at a high flow rate.

[0002]

2. Description of the Related Art This type of filtration tower is disclosed in, for example,
No. 3,315,110, the long fiber bundle used therein is bundled at the lower end thereof in a hole of a perforated plate horizontally provided in the tower main body, and is fixed via a ring. . Such a filtration tower usually has a thickness of about 10 μm.
m, which is an aggregate of non-combustible single fibers such as acrylic fiber, polyester fiber, polyamide fiber, etc., having a length of about 0.1 to about 80 μm.
4m to about 3.0m long fiber bundles are densely arranged in the tower body and upright, so that it can be filtered at a high flow rate without increasing the pressure loss so much as compared with other filter media. There is. During backwashing, the backwash fluid flowing from the gap between the hole of the perforated plate and the lower end of the long fiber bundle causes the long fiber bundle whose upper end is a free end to flow like a stream. It also has the advantage that the suspended matter is effectively removed. However, in a conventional filtration tower,
Since the lower ends of the long fiber bundles are bundled and are very dense, sufficient vibration cannot be ensured only at the lower end, and the backwash effect is not sufficiently obtained near the lower end. Had the problem that

[0003] In order to solve this problem, the present applicant has proposed a filtration tower having the following structure in Japanese Patent Application Laid-Open No. 2-149305. That is, as shown in FIG. 6, the upper lid 101 having a large number of holes 101a around the side trunk, and the lower cylindrical body 102 having slits 102a in the side trunk and having upper and lower ends opened communicate with each other. Support 10
0 to each of the holes 103 of the perforated plate 103 laid laterally in the tower body.
a, the upper lid-like body 101 is attached so as to face above the perforated plate 103, the lower cylindrical body 102 is attached so as to face below the perforated plate 103, and is further extended around the side trunk of the upper lid-like body 101. It is characterized in that the lower end portion 104a of the fiber bundle 104 is fixed.

[0004]

According to the above construction, the compressed air (backwash air) or backwash water at the time of backwashing is supplied to the lower end opening 1 of the lower tubular body 102 constituting the support 100.
02b or the slit 102a formed in the side trunk portion, flows into the lower cylindrical body 102, and the lower end portion 1 of the long fiber bundle 104
The hole 101a of the upper lid-like body 101 to which 04a is fixed.
Erupts from Therefore, the backwash fluid is supplied directly or preferentially to the lower end portion 104a of the dense bundle of long fibers 104, so that the long fiber bundle 104 is formed only by the ring without using such a support 100. The lower end portion 104a can be backwashed far more effectively as compared with the holding structure.

[0005] However, even with such a support 100, the backwashing fluid is ejected from the upper lid 101 disposed inside the long fiber bundle 104, so that the lower end portion 104a of the long fiber bundle 104 is formed. , The suspension is removed relatively well, but the dense fibers 10
Due to the resistance of No. 4, there is a problem that the cleaning tends to be insufficient particularly on the outer side of the lower end portion 104a.

The present invention has been made in view of the above circumstances, and removes suspended matter at the time of backwashing, particularly, removes suspended matter at the lower end portion of a long fiber bundle more effectively than conventional ones. It is an object to provide a filtration tower using a long fiber bundle which can be used.

[0007]

In order to achieve the above object, a filtration tower using a long fiber bundle according to the present invention is supported by being inserted into a hole of a perforated plate provided in the tower body. With the perforated plate as a boundary, the upper position has an upper outlet that functions as a filtered water inlet and a backwash fluid outlet, and the lower position has a lower outlet that functions as a filtered water outlet and a backwash fluid inlet. A hollow support nozzle, and a long fiber bundle whose lower end is connected to a position above the perforated plate of the support nozzle and whose upper end is a free end. In a filtration tower that captures the suspension through the undiluted solution in the countercurrent, the upper hole that functions only as a backwashing fluid outlet at an upper position, with the perforated plate as a boundary, instead of the supporting nozzle, at an appropriate hole in the perforated plate It has an opening and a backwash fluid inlet at the lower position. It has a lower opening that functions only, and the upper end is characterized by being disposed backwash dedicated nozzle hollow which is closed.

[0008] The upper opening of the nozzle for backwashing may be formed at a height substantially equal to or lower than the height of the lower end of the long fiber bundle connected to the support nozzle from the perforated plate. preferable. Further, it is preferable that the nozzle dedicated to backwashing is disposed in at least one of a plurality of holes adjacent to the hole of the perforated plate in which the support nozzle is disposed. Further, it is preferable that a water collecting port that functions only as a filtered water inflow portion is further provided at a position above the support nozzle, in addition to the upper outflow port. When the support nozzle has only the upper outlet, the number of the nozzles dedicated to backwashing is set such that the total opening area of the upper outlet is 3 to 8% of the area of the perforated plate. Is preferably adjusted. On the other hand, in the case where the support nozzle has a water collecting port that functions only as a filtered water inflow portion in addition to the upper outlet port, the total opening area of the upper outlet port and the total opening area of the water collecting port are totaled. It is preferable that the number of nozzles dedicated to backwashing is adjusted so that the total total opening area becomes 3 to 8% of the area of the perforated plate. The long fiber bundle can also be connected to the backwash nozzle.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a filtration tower using a long fiber bundle of the present invention will be described based on an embodiment shown in the drawings. As shown in FIGS. 1, 2 and 4, the filtration tower 1 according to the present embodiment has a tower main body 2, a perforated plate 3, a support nozzle 4, a long fiber bundle 5, a nozzle 6 for backwashing, and the like. It is configured.

As shown in FIG. 4, in the tower body 2, a stock solution supply pipe 10 is connected to an upper wall 2a, and a filtered water outflow pipe 11 and a backwash air supply pipe 12 are connected to a bottom wall 2b. . As shown in FIG. 4, the stock solution supply pipe 10 is connected not only to a stock solution supply source but also to the middle thereof, a coagulant supply pipe 13 for supplying a coagulant as needed. I have. The coagulant supply pipe 13 is connected to a coagulant storage tank 14 via a coagulant supply pump 15. A backwash water supply pipe 16 is connected to the filtered water outflow pipe 11, and a backwash water supply pump 17 is interposed in the backwash water supply pipe 16. The backwash air supply pipe 12 has a blower 18.
Is connected. In addition, the piping for the tower main body 2 shown in FIG. 4 is merely an example, and it is a matter of course that the present invention is not limited to this.

The perforated plate 3 is formed in a substantially disk shape, and is fixed substantially horizontally at a predetermined position closer to the bottom wall 2b than the center in the tower main body 2 (see FIG. 4). As shown in FIGS. 1 and 2, a plurality of holes 3a are formed in the perforated plate 3, and a support nozzle 4 and a nozzle 6 for backwashing described later are inserted into the holes 3a.

As shown in FIGS. 1 and 2, the support nozzle 4 in the present embodiment is composed of a hollow lower cylindrical body 41 and an upper cylindrical body 42. Lower cylindrical body 41
The upper end 41a and the lower end 41b are opened, and a flange portion 41c is protruded from an outer peripheral surface near the upper end 41a. The lower cylindrical body 41 is provided with the holes 3 of the perforated plate 3 until the lower surface of the flange portion 41c contacts the surface of the perforated plate 3.
a is inserted from above with respect to a, and at this time, at an appropriate portion of the peripheral wall that is located below the perforated plate 3, as a filtered water outflow portion and as a backwash fluid inflow portion. A functioning lower outlet 41d is formed with an opening. Reference numeral 43 denotes a nut that is screwed to the peripheral surface of the lower tubular body 41 to fix the lower tubular body 41 to the perforated plate 3.

The upper cylindrical body 42 has an end wall 42 at an upper end 42a.
The lower cylindrical member 41 has an opening at the lower end 42c, and is connected to the peripheral surface of the lower cylindrical body 41 at a position higher than the flange portion 41c by screwing or fitting. In addition, a hole 42d having a predetermined diameter serving as a water collecting port is formed in a substantially central portion of the end wall 42b, and a valve mechanism for opening and closing the hole 42d is provided in the upper cylindrical body 42. . With this valve mechanism, the hole 42d functions only as a filtered water inflow portion, and does not function as a backwash fluid outflow portion. The valve mechanism may have any structure as long as it can open the hole 42d at the time of filtration and close it at the time of backwashing. In the present embodiment, the valve mechanism has a diameter larger than the diameter of the hole 42d. In order to prevent the ball valve 42f from dropping, the ball valve 42f includes a projection 42g which projects inward at a substantially central portion in the longitudinal direction of the upper cylindrical body 42.

An upper outlet 42h which functions as a filtered water inlet and a backwash fluid outlet is opened above the peripheral wall between the projection 42g and the end wall 42b, ie, above the perforated plate 3. Is formed. The shape of the upper outlet port 42h and the lower outlet port 41d of the lower cylindrical body 41 are not limited.
It can be formed in various shapes such as a circle and a long hole.
The diameter of the backwashing fluid is not limited, but is preferably as small as possible in order to increase the outflow speed of the backwash fluid from the upper outlet 42h.

A lower end 5a of the long fiber bundle 5 is fixedly provided around the upper cylindrical body 42 of the support nozzle 4. The fixing method is arbitrary, but in the present embodiment, the band member 44 is fitted around the lower end 5a of the long fiber bundle 5 and fastened and fixed. As the long fiber bundle 5, even if the stock solution having a relatively high flow rate is passed in the downward flow, the lower part is slightly bent and the height is slightly reduced in the initial stage, and the lower part is bent by continuing the flow. The height increases and the height gradually decreases, but still, it is necessary to have a waist strength and filling amount that does not bend horizontally and is almost upright. The long fiber bundle 5 that satisfies such conditions has a thickness of 80 μm or less, usually 35 μm.
It is preferable to use an aggregate of synthetic fibers such as acrylic fibers, polyester fibers, and polyamide fibers before and after, or non-twisted single fibers such as natural fibers such as cotton and wool. However, an aggregate of twisted yarns may be used as long as it does not bend horizontally and is almost upright in the tower body 2 during the passage of the liquid.

The long fiber bundle 5 can remove finer suspended matter as the aggregate density increases, and the quality of the filtered water improves. However, the pressure loss increases as the aggregate density increases. Therefore, the aggregate density may be determined in consideration of the quality or quantity of the suspension of the stock solution. For example, if the length is 1,000-3.0
In the case where an aggregate made of non-twisted single fibers of 00 mm is used, 50 to 200 kg (dry weight) per 1 m ² of filtration cross-sectional area
It is preferable to set the packing density so as to form an aggregate.

In the present embodiment, the backwash nozzle 6 is composed of two members, a lower tubular member 61 and an upper tubular member 62, similarly to the support nozzle 4 described above. Lower cylindrical body 61
Has substantially the same shape as the lower tubular body 41 of the support nozzle 4, has an upper end 61a and a lower end 61b, and has a flange 61c protruding from a peripheral surface near the upper end 61a. However, when it is inserted into the hole 3a of the perforated plate 3 from above and fixedly arranged using the nut 63, the flange portion 61c located above the perforated plate 3
Is formed with an upper opening 61e penetrating in the thickness direction. The upper opening 61e functions only as a backwash fluid outlet, unlike the upper outlet 42h of the upper tubular body 42 constituting the support nozzle 4. Further, a lower opening 61d is formed at an appropriate portion of the peripheral wall that is located below the perforated plate 3. This lower opening 6
1d is different from the lower outlet 41d of the support nozzle 4,
It functions only as a backwash fluid inlet. In order to exhibit only the function relating to the upper opening 61e and the lower opening 61d,
A valve mechanism is provided. Although the structure of the valve mechanism is not limited, in the present embodiment, a partition wall 61h in which a backwash fluid passage hole 61g provided at an appropriate portion between the upper opening 61e and the lower opening 61d is opened. , And a ball valve 61i that opens and closes the backwash fluid passage hole 61g.

The upper cylindrical body 62 has an upper end closed by an end wall 62a, and an open lower end 62.
From the side b, the lower cylindrical body 61 is connected to the peripheral surface above the flange portion 61c by screwing or fitting. Note that, in the present embodiment, the upper opening 61e described above is
1 is formed on the flange portion 61c.
The second peripheral wall may be formed through. However, in order to enhance the cleaning effect, it is necessary to directly collide the backwash fluid ejected from the upper opening 61e with the outside of the lower end portion 5a of the long fiber bundle 5 attached to the adjacent support nozzle 4, so It is preferable that the lowermost portion of the lower end portion 5a of the fiber bundle 5 be provided at a portion having a height substantially equal to or less than the height from the surface of the perforated plate 3. Further, in order to increase the ejection speed of the backwash fluid as much as possible, it is preferable to make the diameter of the upper opening 61e as small as possible.

The backwash nozzle 6 is provided to improve the backwashing performance of the lower end portion 5a of the long fiber bundle 5, so that all the support nozzles 4 have the upper portion of the long fiber bundle 5. It is necessary to arrange so that the backwash fluid ejected from the opening 61e is supplied. Therefore, the backwashing nozzle 6 is always disposed in at least one of the plurality of holes 3a adjacent to the hole 3a of the perforated plate 3 in which the support nozzle 4 is disposed. Is preferred.

On the other hand, if the number of the nozzles 6 dedicated to backwashing which does not have the filtered water passage function is too large, the initial head loss increases and the filtration capacity decreases. In consideration of this, as shown in FIG.
It is more preferable that the backwash-dedicated nozzles 6 are always provided in the holes 3a adjacent in any direction, and that the backwash-dedicated nozzles 6 are not adjacent to each other. That is, the positional relationship is such that one backwashing dedicated nozzle 6 is surrounded by the support nozzle 4.

The number of the support nozzles 4 and the nozzles 6 for backwashing can be roughly determined by the positional relationship between them, but the filtering capacity differs depending on the diameters of the nozzles 4 and 6. In order to prevent this, the total total opening area obtained by adding the total opening area of the upper outlet 42h of the support nozzle 4 and the total opening area of the hole 42d dedicated to collecting water is:
It is preferable to adjust the ratio to 3 to 8% of the entire area of the perforated plate 3. Note that, unlike the present embodiment, when only the upper outlet 42h is provided and the hole 42d is not provided as a dedicated water collecting port, the ratio of the total opening area of the upper outlet 42h is reduced. It is adjusted to be 3 to 8% with respect to the entire area of the plate 3.

Next, referring to FIGS. 1, 2 and 4,
The operation of the filtration tower 1 according to the present embodiment will be described. First, at the time of filtration, the valve 20 provided in the undiluted liquid supply pipe 10 is disposed.
And the valve 21 interposed in the filtered water outflow pipe 11 is opened,
The stock solution is supplied from the stock solution supply pipe 10 into the tower main body 2 (FIG. 4).
reference). By the undiluted solution supplied in the downward flow, the long fiber bundle 5
Since it contracts when passing the liquid, it effectively captures the suspension. The undiluted solution (filtration water) from which the suspended matter was removed was supplied to the upper outlet 4 of the support nozzle 4 as shown by the arrow in FIG.
2h and the hole 42d of the end wall 42b flows into the support nozzle 4, presses the ball valve 42f against the protrusion 42g located below, and passes through the gap between the protrusions 42g to open the lower outflow inlet 41d. It flows out from the lower end 41b and is further discharged from the bottom of the filtration tower 2 to the filtered water discharge pipe 11. At this time, filtered water also flows in from the upper opening 61e formed in the backwashing nozzle 6, but the filtered water flowing into the backwashing nozzle 6 passes through the ball valve 61i to the partition wall 61h.
, The backwash fluid passage hole 61g is closed. Therefore, the filtered water cannot pass through the backwash nozzle 6, but is discharged only through the support nozzle 4 as described above.

During the filtration, the coagulant supply pump 15 is activated as necessary to supply the coagulant from the coagulant storage tank 14, or to supply the pH adjuster together with or instead of this. (See FIG. 4).

If the pressure loss increases due to the suspension adhering to the long fiber bundle 5 due to the filtration, back washing is performed. In the backwashing step, the valve 20 and the valve 21 are closed, and the valve 22 provided in the backwash water supply pipe 16 and the valve 23 provided in the backwash water outflow pipe 19 are opened. 17 is started (see FIG. 4). The backwash water flows from the lower part of the tower main body 2 through the backwash water supply pipe 16 and becomes an upward flow. As shown by an arrow in FIG. Then, it flows in from the opened lower end 41b, and flows into the backwash nozzle 6 from the lower opening 61d and the opened lower end 61b.

The backwash water passing through the support nozzle 4 is shown in FIG.
The ball valve 42f is pushed up as shown in FIG.
The hole 42d is blown out from only the upper outlet 42h. The upper outflow inlet 42h is connected to the lower end 5 of the long fiber bundle 5.
a, the lower end 5a in particular
Is effectively washed from the inside, and the long fiber bundle 5 is vibrated to remove the suspended matter. On the other hand, the backwash water passing through the backwash nozzle 6 as shown by the arrow in FIG.
In order to push up the ball valve 61i and separate it from the partition 61h, the upper opening 61e is passed through the backwash water passage hole 61g.
Erupts from The backwash water spouted from the upper opening 61e is
Since the lower fiber end 5a of the long fiber bundle 5 supported by the adjacent support nozzle 4 is vigorously impacted from the outside to penetrate into the inner part, the separation of the suspended matter from the lower end part 5a is promoted. . At the same time, the suspended matter deposited on the perforated plate 3 is also removed by the jetted backwash water. Then, the backwash water containing the removed suspended matter is discharged through the backwash water outflow pipe 19 (see FIG. 4).

During the backwashing step, if necessary, the valve 24 interposed in the backwash air supply pipe 12 may be opened and the blower 18 may be started to supply backwash air. Of course (see FIG. 4). Further, in order to dissolve and remove slime firmly adhered to the long fiber bundle 5, sodium hypochlorite, hydrogen peroxide,
An oxidizing agent such as ozone may be mixed and supplied.

The valves 20 to 24 are generally automatic valves, but may of course be manual valves, or may be used in combination. Although the valves are individually arranged in each pipe, a single operation valve (multi-way valve) such as a five-way valve may be used by combining several valves.

The filtration tower using the long fiber bundle of the present invention is not limited to the above embodiment. For example, the lower cylindrical body 41 or the lower cylindrical body 61 constituting the support nozzle 4 or the backwashing dedicated nozzle 6, respectively, has an open lower end, and has a lower outlet 41 on the peripheral wall.
Although the one having the lower opening 61d or the lower opening 61d is used, the one having the lower end closed may be used. Conversely, without forming the lower outlet 41d or the lower opening 61d on the peripheral wall,
The opening lower end may be configured to be used as the lower outlet or lower opening. Further, in the above-described embodiment, the support nozzle 4 and the backwash-dedicated nozzle 6 are each configured by combining the upper and lower cylindrical bodies, but may be configured by one integrally formed member. Good.

Further, as shown by imaginary lines in FIGS. 1 and 2, the long fiber bundle 5 may be attached not only to the support nozzle 4 but also to the nozzle 6 dedicated to backwashing. That is, the lower end of the long fiber bundle 5 may be located on the peripheral surface of the portion above the upper opening 61e and fixed with the band member. Compared to the case where the long fiber bundle 5 is provided only in the support nozzle 4, the long fiber bundle 5
, The density inside the tower body 2 can be increased, and as a result, the filtration capacity can be improved. In this case, it is difficult to directly supply the backwash fluid to the lower end of the long fiber bundle 5 attached to the backwash nozzle 6, but the backwash nozzle 6 has a structure in which filtered water does not pass through in the first place. Therefore, the suspended matter hardly accumulates at the lower end of the attached long fiber bundle 5, and there is no problem.

(Example) Diameter 300 mm, tower height 4,000
300m diameter at the lower part of the tower body made of 0mm vinyl chloride
The lower end of a long fiber bundle made of an aggregate of non-twisted single fibers made of acrylic having a thickness of 43 μm and a length of 1,000 mm is fixed to a supporting nozzle, and the upper end is free. Ended. As shown in FIG. 5A, six support nozzles 4 were provided, and one backwash-dedicated nozzle 6 was provided so as to be surrounded by the support nozzles 4. At this time, the total total opening area of the upper outflow inlet and the water collecting port (hole 42d) of the support nozzle 4 was 5.1% of the area of the perforated plate 3.

For the filtration tower, the sewage secondary treatment water (suspension concentration 10 mg /
(1-20 mg / l) at an LV of 20 m / H, and filtration was started. The initial head loss was 5 cm and the suspension concentration of the filtered water obtained was 5 mg / l.

When the head loss reached 1.5 m, the filtration was stopped, and compressed air of LV 400 m / H and backwash water of LV 100 m / H were allowed to flow from the lower part of the tower body in an upward flow for 4 minutes. Backwashing was performed in which backwash water with an LV of 100 m / H was allowed to flow in an upward flow for 2 minutes. Thereafter, the filtration step and the backwashing step were repeated.

Although the filtration step and the backwashing step were repeated for a long period of time, the suspension was hardly observed at any part of the long fiber bundle of the supporting nozzle, and the initial loss immediately after the backwashing was performed. The head was also about 5 to 10 cm.

(Comparative Example) As shown in FIG. 5B, the nozzle for backwashing of the filtration tower used in the example was removed, and the hole of the perforated plate 3 provided with the nozzle for backwashing was used. Is closed, the filtration step is performed under the same conditions while maintaining the total total opening area of the upper outflow inlet and the exclusive water collecting port of the support nozzle 4 as 5.1% of the area of the perforated plate 3 in the same manner as in the above embodiment. The backwash step was repeated for the same period. As a result, a suspension remaining due to insufficient washing was confirmed on the surface of the long fiber bundle, particularly near the lower end of the long fiber bundle, and the initial loss head immediately after the last backwashing was increased to about 20 cm.

[0035]

According to the filtration tower using the long fiber bundle of the present invention, the nozzle for backwashing is provided on the perforated plate, so that the suspended matter is removed at the time of backwashing, especially the lower end of the long fiber bundle. Part of the suspension can be removed more effectively than conventional ones.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing a state of filtration of an embodiment of a filtration tower according to the present invention.

FIG. 2 is a partial cross-sectional view showing a state during backwashing of one embodiment of the filtration tower according to the present invention.

FIG. 3 is a diagram schematically illustrating an example of arrangement of a support nozzle and a nozzle dedicated to backwashing according to the embodiment.

FIG. 4 is a configuration diagram showing an example of piping to a filtration tower according to the embodiment.

5A is a diagram schematically illustrating an arrangement of a support nozzle and a nozzle dedicated to backwash in an embodiment, and FIG. 5B is a diagram schematically illustrating an arrangement of a support nozzle in a comparative example.

FIG. 6 is a sectional view of a main part of a conventional filtration tower.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Filtration tower 2 Tower main body 3 Perforated plate 4 Support nozzle 5 Long fiber bundle 6 Backwash exclusive nozzle

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Seto 1-2-8 Shinsuna, Koto-ku, Tokyo Organo Co., Ltd. (72) Inventor Tomoaki Miyanoshita 1-4-9, Kawagishi, Toda-shi, Saitama Olga Incorporated research institute

Claims (7)

[Claims] 1. An upper outlet which is inserted into and supported by a hole of a perforated plate provided in a tower main body and functions as a filtered water inflow portion and a backwash fluid outflow portion above the perforated plate as a boundary. A hollow support nozzle having an inlet, and having a lower outflow inlet functioning as a filtered water outflow portion and a backwash fluid inflow portion at a lower position, a lower end portion connected at a position above the perforated plate in the support nozzle, and an upper end portion; A long fiber bundle disposed so that the portion becomes a free end, and a filtration tower that captures a suspension by passing the undiluted solution through the long fiber bundle in a downward flow. Instead of the support nozzle, with a perforated plate as a boundary, the upper position has an upper opening functioning only as a backwashing fluid outflow portion, and the lower position has a lower opening functioning only as a backwashing fluid inflow portion, and A hollow backwash nozzle with a closed upper end A filtration tower using a long fiber bundle, which is provided. 2. An upper opening of the nozzle for backwashing is formed at a position substantially equal to or lower than the height of the lower end of the long fiber bundle connected to the support nozzle from the perforated plate. A filtration tower using the long fiber bundle according to claim 1. 3. At least one of a plurality of holes adjacent to a hole of a perforated plate provided with the support nozzle is provided.
The filtration tower using a long fiber bundle according to claim 1 or 2, wherein the nozzle for backwashing is provided in one of the holes. 4. The long fiber according to claim 1, further comprising, at a position above the support nozzle, a water collecting port that functions only as a filtered water inflow portion, in addition to the upper outflow port. Filtration tower using bundles. 5. The number of nozzles dedicated to backwashing is adjusted so that the total opening area of the upper outflow inlet of the support nozzle is 3 to 8% of the area of the perforated plate. 1
A filtration tower using the long fiber bundle according to any one of Items 1 to 3. 6. The total opening area obtained by adding the total opening area of the upper outflow inlet and the total opening area of the water collecting port of the supporting nozzle is 3 to 8% of the area of the perforated plate. The number of nozzles dedicated to backwashing is adjusted as described above.
3. A filtration tower using the long fiber bundle described in 1. above. 7. The filtration tower using a long fiber bundle according to claim 1, wherein the long fiber bundle is also connected to the backwash nozzle.