JP2003190715A - Water treatment method utilizing capillary phenomenon and apparatus therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water treatment method hard to generate the clogging of a filter member and capable of easily washing the filter member to restore water treatment capacity. <P>SOLUTION: Water 11 to be filtered is stored in an aeration tank 82 and the filter member 40 constituted by gathering string-like fiber aggregates is dipped in the water to be filtered. The water to be filtered is filtered at a place where it enters the gaps between fibers from the whole surface dipped in water of the filter member and small groups of microorganisms incapable of entering the gaps between fibers adhere to the surfaces of fibers and the water to be filtered flows through the gaps between fibers naturally by a capillary phenomenon. Thereafter, the small groups of microorganisms adhering to the surfaces of fibers become large gradually as filtering advances to form microorganism colonies. Subsequently, the water to be filtered is filtered at a place where it enters the minute gaps in the microorganism colonies and naturally flows through the minute gaps by a capillary phenomenon to subsequently flow through the gaps between fibers by a capillary phenomenon. The filtered water 25 is discharged to the outside of the aeration tank from the filter member. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water treatment method and an apparatus for the same, which uses a filter member composed of a string-shaped fiber aggregate and utilizes capillary action. TECHNICAL FIELD The present invention relates to a method and an apparatus for water treatment of high-concentration microorganisms inside an aeration tank in the method, and treatment of raw water such as lake water and river water to obtain clean treated water.

[0002]

2. Description of the Related Art There are various types of raw water, and water treatment is performed by various methods according to the raw water. The inventor of the present invention has proposed a water treatment method and an apparatus thereof utilizing the capillarity as a technique related to the present invention (JP-A-11-3.
47313). In this related technique, as shown in FIG. 11, filtered water (raw water) 2 is stored in a filtered water storage part 1. Then, one end of the filtering member 4 covering the upper edge portion 3 of the filtered water storage part 1 is immersed in the filtered water 2, and the other end is positioned outside the filtered water storage part 1. This allows
The filtered water 2 passes through the filtering member 4 from the filtered water storage portion 1 by a capillary phenomenon and then rises, then falls by gravity, and is processed while flowing to the outside of the filtered water storage portion 1. .

[0003]

In this related art, for example, a fiber woven cloth is used as the filter member 4. This fiber woven fabric is in the form of a cloth in which warp yarns and weft yarns are interlaced and woven. The suspended solids contained in the raw water adhere to the fiber woven cloth, but if the adhered amount increases, the fiber woven cloth is clogged and the flow rate also gradually decreases. In some cases, a nonwoven fabric such as a cloth-like filedone nonwoven fabric is used instead of the fiber woven fabric. When the cloth-like filter member such as the fiber woven cloth or the non-woven cloth is clogged, it is necessary to remove the attached solid matter by washing to recover the water treatment capacity. However, even with high-pressure washing, it was difficult to sufficiently remove even the solid matter adhering to the inside of the filtration member.

In the case of a fiber woven fabric, there are fibers that intersect in the flow direction of the water to be filtered, and these fibers prevent the rise of water due to capillary action. Therefore, the capillarity is less likely to occur, and the flow rate of the filtered water after the treatment is small, which is not economical and practical. Further, if floating solid matter adheres to the inside of the gap between the warp yarn and the weft yarn of the fiber woven fabric, it is difficult to remove it by washing. Moreover, in the case of a cloth-shaped filter member, it tends to dry gradually with the passage of time, so it was necessary to occasionally wet the filter member with water. In addition, in the case of non-woven fibers, a siphon phenomenon has occurred in addition to the capillary phenomenon. Therefore, when the water to be filtered flows on the surface of the filtration member due to this siphon phenomenon, the suspended solids tend to pass through without being sufficiently attached to the fibers of the filtration member. As a result, the quality of the filtered water may not be so good in some cases.

As another water treatment method, there is a case in which a water treatment is carried out by a pressure floating method or a coagulating sedimentation method after injecting a chemical into raw water at the time of water intake at a water supply site. But,
In these water treatment methods, it is necessary to pay attention to the safety of chemicals contained in clean water, and the running cost is high. Generally, in the water treatment method, COD of raw water
It is very difficult to reduce (chemical oxygen demand). Therefore, in the past, expensive activated carbon was used for COD.
Since there were many cases to remove, the development of new technology was required. Further, in the activated sludge method, the maximum concentration of activated sludge in the aeration tank is, for example, about 5,000 ppm to about 10,000 ppm, and it has been difficult to operate at a higher concentration. In addition, it was necessary to pay close attention to the maintenance of the equipment so that the activated sludge did not float in the settling tank.

The present invention has been made in order to solve the above problems, and the filter member made of a string-shaped fiber aggregate is less likely to be clogged, and the filter member is easily washed to treat water. An object of the present invention is to provide a water treatment method utilizing capillarity and an apparatus thereof capable of recovering the ability.

[0007]

In order to achieve the above-mentioned object, a water treatment method utilizing capillary action according to the present invention is
The filtered water is stored in the filtered water storage portion, and a part or almost all of a filtering member provided in the filtered water storage portion and configured by a plurality of elongated string-like fiber aggregates is used as the filtered water. By soaking, the water to be filtered is filtered where the water to be filtered enters the gaps between the fibers from the entire surface of the filtering member that has been soaked in water, and the small population of microorganisms that cannot enter between the fiber gaps is the fibers. Attached to the surface of, the water to be filtered naturally flows through the interfiber gap by capillary action,
Thereafter, the small population of the microorganisms attached to the surface of the fiber gradually increases as the filtration progresses to form a microbial colony that has a minute gap inside and exhibits a filtering function, and thereafter All or part of the filtered water
After being filtered where it enters the minute gaps inside the microbial colony, it naturally flows through the minute gaps by capillary action, then naturally flows through the interfiber gaps by capillary action, and the filtered water is It was made to flow out from the filtering member and be discharged to the outside of the filtered water storage part. A water treatment device utilizing a capillary phenomenon suitable for carrying out the method is provided in the filtered water storage part in which the filtered water is stored, and the filtered water storage part, and part or almost all of the above is provided. A filtering member that is immersed in water to be filtered and is composed of an assembly of a plurality of long and narrow string-like fiber aggregates, a filtered water discharging unit for discharging filtered water flowing out from the filtering member, and the filtering member is washed. And a cleaning means for the said filtered water, wherein the water to be filtered is filtered from the entire surface immersed in water of the filtration member where it enters the gaps between the fibers, and a small population of microorganisms that do not enter between the fiber gaps are said fibers. Attached to the surface of, the water to be filtered naturally flows through the interfiber gap by capillarity, then the small population of the microorganisms attached to the surface of the fibers gradually increases as the filtration proceeds, A small gap inside To form a microbial colony exhibiting a filtration function, and thereafter, all or part of the water to be filtered is filtered at a place where it enters the minute gap inside the microbial colony, and The filtered water naturally flows through the gaps by the capillarity, and then naturally flows through the interfiber gaps by the capillarity, and the filtered water flows out of the filtering member and is discharged from the filtered water storage unit by the filtered water discharging means. To be discharged to.

Almost all of the filtering member is immersed in the filtered water, and the filtered water discharging means is a partition provided inside the filtered water storing section for partitioning the filtered water. A filtering member support part having a wall and supporting the filtering member with this partition wall, and communicating with the filtering member support part, for flowing the filtered water flowing out from the filtering member to the outside of the filtered water storage part And a water level difference setting means for setting a water level difference so that the downstream side water level of the filtered water is lower than the water level of the filtered water. The cleaning means comprises an air supply device provided in the filtered water storage part so that air can be dispersed and supplied into the filtered water below the filtering member, and a flow path of the filtered water discharging means. It is preferable that the filtration member has a structure capable of supplying a backwashing fluid via the backwashing device and a backwashing device for reducing or removing the excessively large microbial colonies. In addition, the backwash device,
It is preferable to supply air or water for backwashing to the filter member. Preferably, the water level difference setting means is capable of adjusting the water level difference within a range of about 10 cm to about 100 cm.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An example of an embodiment according to the present invention will be described below with reference to FIGS. INDUSTRIAL APPLICABILITY The water treatment method and its apparatus of the present invention are applied to the water treatment of highly concentrated microorganisms in the aeration tank in a typical activated sludge method among sewage treatment methods. Further, the method and apparatus of the present invention treats raw water having a relatively low concentration of suspended solids (SS) (water before treatment supplied to the water treatment apparatus) to obtain clean treated water (treated water). ) Is also used to get. For example, when treating river water or lake water (raw water) taken from a river or lake at a water supply plant to obtain clean water (drinking water), when treating well water (raw water) to clean water, or pool water There are cases in which (raw water) is treated and reused, precision treatment is performed using ultrafine fibers, and treatment equivalent to treatment in the settling tank and sand filter of wastewater treatment equipment is performed.

(First Embodiment) A first embodiment in which water treatment is carried out using a filter member made of a string-shaped fiber aggregate will be described with reference to FIGS. 1 to 3. In each of the following embodiments, the same or corresponding parts as those in the other embodiments are designated by the same reference numerals and the description thereof will be omitted. Figure 1
2 is a diagram for explaining the capillarity, FIG. 2 is a diagram showing the first embodiment, FIG. 2 (A) is a schematic configuration diagram of a water treatment device, and FIG. 2 (B) is a plan view of a filtering member. 2 (C) is an enlarged cross-sectional view of the string-shaped fiber assembly that constitutes this filtration member.

First, the capillary phenomenon will be described.
When a thin tube is erected vertically on the water surface, water rises inside the tube and the water level inside the tube is higher than the water level outside the tube.
Such a phenomenon is called a capillary phenomenon. It is this capillary phenomenon that causes trees and flowers to absorb water from the ground. The height of the water surface rising in the tube due to the capillarity is determined by the magnitude relationship between the cohesive force between water molecules and the adhesive force between the water and the tube wall. As shown in FIG. 1, the plurality of string-shaped fiber aggregates 12 constituting the string-shaped filter member 10 are
It consists of many fibers 13. In the string-shaped fiber assembly 12, the fibers 13 are entangled with each other, and a narrow gap is formed between the fibers 13. Further, a narrow gap is also formed between the fiber 13 of the string-shaped fiber assembly 12 and the fiber 13 of another string-shaped fiber assembly 12. These gaps are pseudo fine tubes 14, which are similar to fine tubes.
Make up 15. Therefore, when the filtering member 10 stands upright (or inclined) to the filtered water 11, a capillary phenomenon occurs.

The filtered water 11 wets the surface of the fiber 13,
Although it tries to spread as a thin film on this surface, it tries to reduce the surface area due to surface tension. As a result, the filtered water 11 rises in the pseudo fine tubes 14 and 15 due to the capillary phenomenon. As a result, water films 17 and 18 having film thicknesses d and d1 are formed on the pseudo fine tubes 14 and 15. Taking one pseudo fine tube 14 as an example, the water inside the pseudo fine tube 14 tends to be pulled down to the same height as the external water surface 16 by gravity, so that the pseudo fine tube 14 is balanced by surface tension and gravity. The height h of the water in the pipe 14 is determined. Assuming that the pseudo fine tube 14 has a circular shape with a diameter d, the height h of the liquid surface of the water film 17 raised is expressed by the following equation. From this equation, it can be seen that the smaller the film thickness d, the higher the rising height h of the liquid surface. h = 4T cos θ / (dρg) h: height of rise of liquid surface d: film thickness ρ: density of water g: acceleration of gravity T: surface tension θ: contact angle

The present inventor has focused on the cohesive force between water molecules, which causes capillarity, and provides a water treatment method and apparatus capable of filtering raw water using a string-shaped filter member 10. It was realized. 1 and 2 (A), the water treatment device 20 is provided in the filtered water storage part 21 in which the filtered water 11 is stored and in the filtered water storage part 21, and a part of the water treatment device 20 is in the filtered water 11. In order to wash the filter member 10, a string-shaped filter member 10 soaked, a filtered water discharge means 19 for discharging the filtered water (water after being filtered by the filter member) 25 flowing out from the filter member 10. And cleaning means 33. The water 11 to be filtered is filtered where the water 11 to be filtered enters the gaps between the fibers 13 from the entire surface of the filtering member 10 that has been soaked in water, and a small group of microorganisms (flock: microorganisms) that cannot enter the gaps between the fibers 13 Aggregates) adheres to the surfaces of the fibers 13, and the filtered water 11 naturally flows through the gaps between the fibers 13 by a capillary phenomenon. After that, the small group of the microorganisms attached to the surface of the fiber 13 gradually increases as the filtration progresses, and has a minute gap inside to exhibit a filtering function. A microbial colony (visible aggregate of microorganisms). To form. After that, all or part of the water to be filtered 11 is filtered at a place where it enters a minute gap inside the microbial colony having a filtering function, and then naturally flows through the minute gap by a capillary phenomenon, and then, It flows naturally through the gaps between fibers due to the capillary phenomenon. The filtered water 25 is the filtering member 1
0, and is discharged to the outside of the filtered water storage part 21 by the filtered water discharging means 19. The filtering member 10 is composed of a set of a plurality of elongated fiber-shaped fiber assemblies 12. The filtering member 10 includes an upper edge portion 22 of the filtered water storage portion 21.
It is installed so as to cover the. Filtration member 10
One (for example, one end 23) is immersed in the filtered water 11, and the other (for example, the other end 24) is filtered water storage part 21.
Located outside of.

The filtered water 11 passes through the filtering member 10 from the filtered water storage portion 21 by a capillary action to rise (arrow B) and then descends due to gravity (arrow C), and the filtered water storage portion 2
It flows to the outside of 1. Filtered Water 1 in Filtered Water Reservoir 21
The water level Lb of 1 is always maintained constant by supplying the filtered water 11 with the pump 36. A filtered water storage portion 26 for storing filtered water 25 is disposed below the filtered water storage portion 21. The water level Lc of the filtered water 25 in the filtered water storage unit 26 is located below the water level Lb of the filtered water 11. The filtered water storage part 26 is the filtering member 1.
The filtered water 25 flowing down from 0 is received and stored. When the other end 24 of the filtering member 10 is located above and above the water surface of the filtered water storage portion 26 (FIG. 2A), the other end 24 is located below the water level Lb of the filtered water 11. ing. The water level difference Ha in this case is a height dimension from the downstream water level La of the filtered water 25 (that is, the height position of the other end 24 of the filtering member 10) to the water level Lb of the filtered water 11. That is, the water level difference Ha = water level Lb−downstream water level La. Separately from this, the other end 24 of the filtration member 10 may be immersed in the filtered water 25 in the filtered water reservoir 26 (not shown). The water level difference Ha in this case is the downstream water level La of the filtered water 25.
(That is, from the water level Lc of the filtered water 25), the filtered water 1
It is the height dimension up to the water level Lb of 1.

The filtered water 11 naturally flows due to the position energy due to gravity based on the water level difference Ha and the cohesive force between water molecules, and moves from the filtered water storage part 21 to the filtered water storage part 26. . That is, since the filtering member 10 has the pseudo fine tubes 14 and 15, the capillary phenomenon occurs in the pseudo fine tubes 14 and 15. Due to this capillary phenomenon, the filtered water 11 in the filtered water storage portion 21 becomes water films 17 and 18 and rises in the pseudo fine tubes 14 and 15 as shown by an arrow B, and the height of the upper edge portion 22 is increased. Reach position (or higher position). A portion of the filtering member 10 in which the filtered water 11 is rising due to the capillary phenomenon is referred to as a rising portion 30. The filtered water 11 contains a large amount of suspended solids larger than the film thickness d, d1 of the water films 17, 18 formed at the pseudo fine tubes 14, 15. Therefore, among the suspended solids contained in the filtered water 11, suspended solids having a thickness greater than d and d1 cannot pass through the pseudo fine tubes 14 and 15. Therefore, the suspended solid matter is attached to and removed from the filtration member 10. This filtration is mainly performed in the water of the filtered water 11 stored in the filtered water storage part 21. In this way, the size of the suspended solids to be removed is determined by the dimensions of the film thicknesses d and d1. Therefore, depending on the type, size, particle size distribution, etc. of suspended solids contained in the water to be filtered 11, the optimum material for the filtering member 10 and the size, density, etc. of the string-shaped fiber aggregate 12 and the fiber 13 should be selected. Just go.

The filtered water 11 rises in the rising portion 30 and reaches the height position of the upper edge portion 22 (or a position higher than this). After that, the filtered water 11 flows through the filtering member 10 by gravity as shown by an arrow C, and flows to the outside of the filtered water storage part 21. A portion of the filtering member 10 where water descends is referred to as a descending portion 31. In the descending portion 31, water becomes water films 17 and 18 and flows downward in the pseudo fine tubes 14 and 15 by gravity, and then flows down to the filtered water storage portion 26.
Filtered water discharge means 19 for discharging the filtered water 25 flowing out from the filtering member 10 by the rising part 30 and the descending part 31.
Is configured. While the filtered water 11 enters the filtering member 10 and naturally flows through the rising part 30 and the descending part 31,
Contact with air. Since the entire surface of the filtering member 10 is uneven, the surface area is large. Moreover, the filtered water 11 naturally moves at a low speed due to the position energy due to gravity based on the water level difference Ha and the cohesive force between water molecules. Therefore, the filtered water 11 has a sufficient area in the filtering member 10 and contacts the air for a sufficient time. As a result, organic matter in water is oxidatively decomposed by aerobic microorganisms. The water to be filtered 11 is subjected to the above-mentioned filtration treatment as well as oxidative decomposition treatment with aerobic microorganisms. As a result, the filtered water 11 becomes clean filtered water (treated water) 25.
And is stored in the filtered water storage unit 26.

The cleaning means 33 sprays water (for example, raw water, filtered water, filtered water, etc.) 35 onto the filtering member 10 in the filtered water storage section 21 to clean the filtering member 10. A washing conduit 34 is provided slightly above the water surface in the filtered water storage portion 21 and in the water. The cleaning means 33 cleans the filter member 10 by injecting water 35 or air 35a from the cleaning pipeline 34. In the filtering member 10,
A lot of suspended solids adhere to the vicinity of the boundary with the water surface. Therefore, it is preferable to inject the water 35 onto the surface of the filtering member 10 near the boundary with the water surface and diffuse the air 35a into the underwater filtering member 10.

As shown in FIGS. 2 (A) and 2 (B), the filtering member 10 has a flow direction of the filtered water 11 (directions of arrows B and C).
It is composed of a plurality of long and narrow cord-shaped fiber aggregates 12. That is, the filter member 10 is configured in a "comb shape" by the string-shaped fiber aggregate 12 made of only warp threads. The filtering member 10 has a sewn portion 32 for making the plurality of cord-shaped fiber aggregates 12 into a flat bundle. In the sewn-together portion 32, since the string-shaped fiber aggregates 12 are in a state of being uncompressed and not compressed, the filtered water 11 can easily pass through the inside of the sewn-together portion 32. Since the sewn portion 32 is hung on the upper edge portion 22, the filtered water 11 flowing in the string-shaped fiber assembly 12 is
Does not directly contact the upper edge portion 22. Stitching part 32
One side 32a and the other side 32b are respectively located inside and outside the filtered water storage part 21. Diameter e of the string-shaped fiber assembly 12 (FIG. 2 (C))
Is appropriately selected according to the type, size, particle size distribution, etc. of suspended solids contained in the filtered water 11. In the filtering member 10 shown in FIG. 2, when the diameter e of the string-shaped fiber aggregates 12 on the one side 32a and the other side 32b is the same (for example,
The diameter e is about 3 mm).

The composition of the filter member 10 is preferably selected from at least one selected from the group consisting of polyester synthetic fibers, rayon, acrylic fibers, cotton, hemp, wool and silk. For example, the filtering member 10 is composed of about 40% by weight of polyester synthetic fiber, about 40% by weight of rayon, and about 20% by weight of acrylic fiber. The following polymer compounds may be used as the material of the filtering member 10. For example, ethyl cellulose, cellulose acetate, nylon, vinylon, acetate, cupra,
Acrylonitrile, polyethylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polystyrene, polytetrafluoroethylene, ethylene polyterephthalate, polytrifluoroethylene, polychlorotrifluoroethylene, polyvinyl alcohol, polypropylene,
Examples thereof include polymethylmethacrylate.

Next, the experiment conducted by the present inventor will be described. The experimental conditions are as follows.・ Filtration member 4 (conventional product): Firedone non-woven fabric ・ Filtration member 10 (product of the present invention): 40% by weight of polyester synthetic fiber, 40% by weight of rayon, 20% by weight of acrylic fiber ・ Dimensions of filtering member 4, 10: about 13 cm (Width D) x approx. 30
cm (length L) -Dimensions of filtered water storage part 21: 20 cm (length) x 30 cm
(Horizontal) × 24 cm (height) -Water to be filtered 11: Lake water collected in Kasumigaura (lake) As a conventional cloth-shaped filtering member 4 (FIG. 11), a non-woven firedone was used. As the filter member 10 of the present invention, a commercially available replacement yarn for mop sewn in a bundle at the sewn portion was used. The string-like fiber assembly 12 of the filtration member 10 has a diameter e of about 3 mm.

A predetermined amount of filtered water 1 is stored in the filtered water storage section 21.
1 to store the conventional filtration member 4 and the filtration member 10 of the present invention.
For each of the above, the filtered water 25 filtered by the filtering member and stored in the filtered water storage unit 26 was measured. The other ends 24 of the filtering members 4 and 10 are separated from the water surface of the filtered water 25 in the filtered water storage section 26. Table 1 shows the filtration member 10
When water treatment is performed by the water treatment device 20 using
The water quality of the filtered water and the flow rate and water quality of the filtered water 25 flowing through the filtering member 10 are shown. The flow rate and the water quality of the filtered water 25 were measured 2 hours after the start of water treatment (start of water flow).

[0022]

[Table 1]

As can be seen from Table 1, according to the filtering member 10, COD (chemical oxygen demand) in the water 11 to be filtered,
The concentration (SS), chromaticity and turbidity of the suspended solids were sufficiently reduced, and a desired flow rate could be obtained. That is, it was confirmed that the filtration member 10 has a sufficient water treatment capacity and the quality of the filtered water 25 is also good. When the cleaning means 33 was used for cleaning, the filtering member 10 was cleaned well, and the attached solid matter could be easily removed.

Table 2 shows the firedone non-woven fabric and the filtration member 10.
In the case of, the change in water treatment capacity with time is shown. The same filtered water 11 as in the above experiment was used, and the measurement was performed under the same experimental conditions. At the start of the water treatment, the firedone nonwoven fabric was set in the upper edge portion 22 of the filtered water storage portion 21 in a wet state with water and the filtering member 10 in a dry state. And
Continuous operation was carried out for 36 hours while passing water, and the water treatment capacity was measured after 2 hours and 12 hours. After that, the filtering member 10 was washed with the washing means 33, and at the time when 2 hours had passed after washing, the degree of recovery of the water treatment capacity was measured.

[0025]

[Table 2]

As can be seen from Table 2, in the case of the firedone non-woven fabric, the flow rate gradually decreases due to the adherence of suspended solids and the drying of the firedone non-woven fabric. Also,
If the firedone nonwoven fabric is not wet with water first, the filtered water 11 will rise only partway due to the capillary phenomenon, and the water treatment will not start. Therefore, at the beginning, it was necessary to wet the firedone nonwoven fabric with water. Further, in the case of the firedone nonwoven fabric, the COD, chromaticity and turbidity of the filtered water 25 are not so improved. After cleaning the firedone nonwoven fabric 2
At the end of the time, the flow rate has recovered, but the suspended solids concentration (SS) and turbidity recovery is low.

On the other hand, in the case of the filter member 10 of the present invention, the capillarity spontaneously started without having to wet the filter member 10 with water at the start of water flow (at the start of water treatment). Since the capillarity continued after that, the filtering member 10 did not dry in the middle. Moreover, the quality of the filtered water 25 was maintained in a good state even after a lapse of time, and clean filtered water 25 could be obtained. Further, the filtered water 11 is filtered where the filtered water 11 enters the gaps between the fibers from the entire surface of the filtering member 10 that has been soaked in water, and a small group of microorganisms (for example, at the beginning of generation) that cannot enter the gaps between the fibers. Is a few mm)
Adheres to the surface of the fibers, and the filtered water 11 naturally flows through the interfiber gaps by a capillary phenomenon. After that, the small population of the microorganisms attached to the surface of the fibers gradually increases as the filtration progresses, and forms a microbial colony that has a minute gap inside and exhibits a filtering function. After that, all or part of the water to be filtered 11 is filtered where it enters the minute gaps inside the microbial colony, and then naturally flows through the minute gaps by capillary action, and then the interfiber gaps. Flow naturally through the capillarity. That is, it is understood that what is filtered at this time is mainly the minute gaps in the microbial colony, and the inter-fiber gaps of the filtration member 10 mainly exert the function of introducing water by the capillary phenomenon. The size of the interstices between the fibers (for example, the inner diameter is about 20 to 30 μm), the size of the microbe particles (for example, about 1 to 2 μm), and the size of the minute interstices inside the microbial colony (for example,
The inner diameter was about 1 μm or less) and the like could be confirmed by a micrograph. The flow rate of the filtered water 25 gradually decreases due to the adherence of suspended solids to the filtering member 10, but if the filtering member 10 is washed during the process, the original amount of water can be easily recovered. It was also confirmed that the quality of the filtered water 25 was recovered by this washing. As described above, the filtering member 10 was easier to clean and the cleaning effect was better than that of the firedone nonwoven fabric.

FIG. 3 is a partially enlarged view of the filter member. Figure 3
(A) shows the filtration member 10 of the present invention, and FIG. 3 (B) shows a conventional cloth-like filedone nonwoven fabric 37. Figure 3
In the filtering member 10 shown in FIG.
Even if adhered, the string-shaped fiber aggregates 12 can be easily loosened and separated during cleaning. Therefore, since the inside of the filtration member 10 can be sufficiently washed, the attached solid matter 38 is easily removed.
On the other hand, in the cloth-like filedone non-woven fabric 37 shown in FIG. 3 (B), when the solid matter 38 is adhered in the gaps between the fibers, the solid matter 38 is removed even by washing. It is difficult. In the experiment shown in Table 2, the filtration member was replaced with a conventional firedone non-woven fabric, and the filtration member 10 having a large "wet" to water was used. The composition of the filter member 10 is, for example, about 40% by weight of polyester-based synthetic fiber, about 40% by weight of rayon and about 20% by weight of acrylic fiber. In this case, filtered water 25 with a large amount of water and good quality could be obtained.

(Second Embodiment) FIGS. 4 to 8 are views showing a second embodiment of the present invention. 4 is a schematic configuration diagram when the filtering member 40 is used, FIG. 5 is a schematic configuration diagram showing a more specific water treatment device 46, and FIG. 6 is a VI of FIG.
-VI line sectional drawing, FIG. 7 is a schematic block diagram which shows the time-dependent change of one string-shaped fiber assembly 43. As shown in FIG. As shown in FIG.
The water treatment device 41 includes a filtered water storage part 45, a string-shaped filtering member 40, a filtered water discharging means 47 for discharging the filtered water 25 flowing out from the filtering member 40, and a filtering member 40.
And a cleaning means 48 for cleaning. The filtered water 11 is stored in the filtered water storage section 45. The entire filtering member 40 provided in the filtered water storage portion 45 is immersed in the filtered water 11. As a result, the filtered water 11 is filtered where the filtered water 11 enters the interfiber gap from the entire surface of the filtering member 40 that has been immersed in the water, and a small group of microorganisms that cannot enter the interfiber gap is deposited on the surface of the fiber. The adhered water 11 to be filtered naturally flows through the inter-fiber gaps by a capillary phenomenon. After that, the small population of the microorganisms attached to the surface of the fiber gradually increases as the filtration proceeds,
It forms a microbial colony that has a minute gap inside and exhibits a filtering function. After that, all or part of the water to be filtered 11 is filtered at a place where it enters a minute gap inside the microbial colony, and then naturally flows through the minute gap by a capillary phenomenon, and then the interfiber gap. It flows naturally due to the capillary phenomenon. The filtered water 25 flows out from the filtering member 40 and is discharged to the outside of the filtered water storage part 45 by the filtered water discharging means 47.

Outside the filtered water storage portion 45, the filtered water 2
A filtered water storage part 49 for storing 5 is provided. The filtering member 40 includes a plurality of long and narrow string-like fiber assemblies 4
It is composed of 3 sets. String-like fiber assembly 43
Is formed into a "comb-like shape" with only warp threads.
The filtering member 40 is connected to a pipe 50 serving as a water guiding section in the water 11 to be filtered. The pipe 50 extends from the water under the filtered water 11 to the outside of the filtered water storage part 45 and above the filtered water storage part 49. The inside of the pipe 50 is always filled with the filtered water 25. Pipe 50
Is a filtered water discharge means 47 for discharging the filtered water 25 flowing out of the filtering member 40 to the outside of the filtered water storage part 45.
Are configured.

In order to allow the filtered water 11 to enter the interstices between the fibers from the entire surface of the filtering member 40 which is immersed in water, and to allow the interstices between the fibers to flow naturally, the downstream water level of the filtered water 25. La is set to be lower than the water level Lb of the filtered water 11 in the filtered water storage portion 45. Water level L of filtered water 11
The difference between b and the downstream water level La of the filtered water 25 is the water level difference H.
a. In this case, the height position of the downstream end portion 51 of the pipe 50 corresponds to the downstream water level La. When the downstream end 51 is immersed in the filtered water 25 in the filtered water reservoir 49, the water level Lc of the filtered water 25 in the filtered water reservoir 49 is the downstream water level of the filtered water 25. This corresponds to La. The water guide portion for flowing the filtered water 25 to the outside of the filtered water storage portion 45 may be the same as or similar to the string-shaped filtering member 40 in addition to the pipe 50. In this case, the filtered water 25 will flow through the water guiding portion due to a capillary phenomenon or the like. The cleaning means 48 is composed of an air supply device 55 provided in the filtered water storage part 45. The air supply device 55 is arranged below the filtering member 40 and is provided with the air 54.
Can be supplied dispersed in the filtered water 11. By supplying the air 54 with the air supply device 55 and moving the filter member 40 with a large number of bubbles 54a, the microbial colonies (for example, solid matter made of activated sludge) that are attached to the filter member 40 and become large are reduced. Or remove. As a result, the filtering member 40 is washed, so that the water treatment device 4
1 can be continuously operated.

In this water treatment device 41, filtered water 25
However, when it falls apart from the downstream end portion 51 of the pipe 50, the amount of the filtered water 25 in the pipe 50 decreases. Then, the filtered water 25 remaining inside the pipe 50 naturally flows to the downstream side due to the energy of the position due to gravity based on the water level difference Ha and the cohesive force between water molecules. Since the filtered water 25 flows, the filtered water 11 also has a water level difference Ha.
Based on the energy of the position due to gravity and the cohesive force between water molecules, it enters a minute gap inside the microbial colony and naturally flows to the downstream side through the minute gap, and then the surface of the filtering member 40. Into the gap between the fibers,
The inter-fiber gap naturally flows downstream. Since this water treatment device 41 uses the string-shaped filter member 40,
The filtering member 40 is unlikely to be clogged. Further, the filtering member 40 can be easily washed by the air supply device 55 to recover the water treatment capacity.

As shown in FIGS. 5 and 6, the water treatment device 46 carries out water treatment by the activated sludge method, and the filtered water storage portion 45 has a function of an aeration tank. The water treatment device 46 includes a filtered water storage part 45 and a string-shaped filtering member 4
It has 0 and. Further, the water treatment device 46 includes a filtered water discharging means 57 for discharging the filtered water 25 flowing out from the filtering member 40, and a cleaning means 56 for cleaning the filtering member 40. The filtered water storage part 45 stores the filtered water 11. The entire filtering member 40 provided in the filtered water storage portion 45 is immersed in the filtered water 11. As a result, the filtered water 11 is filtered where the filtered water 11 enters the gaps between the fibers from the entire surface of the filtering member 40 immersed in the water, and the small population of microorganisms that cannot enter the fiber gaps is The water 11 to be filtered adheres to the surface and naturally flows through the interfiber gaps by a capillary phenomenon. Then, a small population of the microorganisms attached to the surface of the fiber,
As the filtration progresses, it gradually becomes larger and forms a microbial colony that has a minute gap inside and exhibits a filtering function. After that, all or part of the water to be filtered 11 is filtered at a place where it enters a minute gap inside the microbial colony, and then naturally flows through the minute gap by a capillary phenomenon, and then the interfiber gap. It flows naturally due to the capillary phenomenon. The filtered water 25 flows out from the filtering member 40,
The filtered water discharge means 57 discharges the filtered water to the outside of the storage part 45.

The filter member 40 is composed of a set of a plurality of elongated fiber-shaped fiber assemblies 43. The water level Lb of the filtered water 11 in the filtered water storage portion 45 is always kept constant by a water level adjusting means (not shown). The filtered water discharging means 57 includes a filtering member supporting portion 60, a water guiding portion 61, and a water level difference setting means 62. Filtering member support 60
Is provided inside the filtered water storage portion 45. The filtering member supporting portion 60 has a partition wall 63 that partitions the water to be filtered 11 and the filtering member 40 is separated by the partition wall 63.
I support you. The partition wall 63 has a hollow cylindrical shape with both ends closed. The partition wall 63 is formed with a plurality of (here, four) slits 64 extending in a direction parallel to the central axis thereof. The filtering member 40 is supported by the slit 64. The radially outer side of the cylindrical partition wall 63 is the region of the filtered water 11, and the radially inner side is the downstream space 65. The filtering member 40 is engaged with the slit 64 so that the slit 64 is closed and there is no gap. As a result, the filtered water 11 does not pass through the inside of the filtering member 40 and does not short-pass directly to the downstream space 65. Since most of the filtering member 40 is in contact with the water to be filtered 11, the filtering area is large. One end of the filtering member 40 is located inside the downstream space 65. The water to be filtered 11 naturally flows through a minute gap inside the microbial colony by a capillary phenomenon, and then the filtering member 40.
Enter the gaps between the fibers from the surface of, and naturally flow through the gaps between the fibers due to the capillary phenomenon to move to the downstream space 65.

The water guiding portion 61 communicates with the filtering member supporting portion 60. The water guiding section 61 is for flowing the filtered water 25 flowing out of the filtering member 40 to the outside of the filtered water storage section 45, and is configured by a pipe 50 or the like. The upstream end of the pipe 50 is attached to the filtering member support 60 in a state of communicating with the downstream space 65. The water level difference setting means 62 sets the water level difference Ha such that the downstream water level La of the filtered water 25 is lower than the water level Lb of the filtered water 11 in the filtered water storage part 45. Filtered water 25
The downstream water level La is such that the downstream end 51 of the pipe 50 can be positioned at a desired height position. Accordingly, the water level difference setting means 62 causes the water level difference Ha to be about 10 cm.
It can be adjusted within a range of from about 100 cm. Due to the energy of the position of gravity based on the set water level difference Ha and the cohesive force between the molecules of water, the filtered water 11 is filtered by the filtering member 4.
The filtered water 11 is filtered where it enters the gaps between the fibers from the entire surface soaked in 0 of water, and a small group of microorganisms that cannot enter the gaps between the fibers adheres to the surface of the fibers, and the filtered water 11 is The fibers naturally flow through the interstices between the fibers due to a capillary phenomenon. Further, the water to be filtered 11 enters a minute gap inside the microbial colony, naturally flows through the minute gap, and then enters a gap between the fibers from the surface of the filtering member 40,
The fibers will naturally flow to the downstream side.

The cleaning means 56 includes an air supply device 67 provided in the filtered water storage portion 45 and a backwash device 68. The air supply device 67 can disperse and supply the air 66 in the water 11 to be filtered below the filtering member 40. The air supply device 67 has a plurality of nozzles 72 arranged below the filtering member 40. Air 66 is the nozzle 72
Is dispersed and supplied into the filtered water 11. Bubbles 6
By 6a, the filtered water 11 is aerated, and the microbial colonies (activated sludge (solid matter)) attached to the surface of the filtration member 40 and growing are reduced or removed. The backwashing device 68 has a structure capable of supplying air 66 as a backwashing fluid to the filtering member 40 via the flow path of the filtered water discharging means 57. The backwash device 68 has a function of reducing or removing the microbial colonies that have grown too large. Backwash air 66
Are supplied as needed (or intermittently). Water (for example, filtered water 25) may be used instead of air as the fluid for backwashing. Air supply device 67
The backwash device 68 is supplied with air 66 from a blower 69 or an air compressor (not shown). A valve 70 provided in the flow path of the air 66 and a valve 71 provided in the pipe 50 can supply, stop, and switch the air 66. The filtered water 25 that has flowed through the water guiding section 61 is stored in the filtered water storage section 49, and is then discharged by the pump 73 as treated water as indicated by arrow F4. In the experiment described below, the continuous operation was performed by returning the filtered water 25 discharged by the pump 73 to the filtered water storage portion 45 to form a circulation flow path.

As shown in FIGS. 5 to 7, in the water treatment device 46 having the above-mentioned structure, the filtered water 11 in the filtered water storage portion 45 has the energy of the position due to gravity based on the water level difference Ha and the water. Due to the cohesive force between the molecules, the entire surface of the string-shaped fiber assembly 43 immersed in water enters the gaps 74 between the fibers 13 and naturally flows through the inter-fiber gaps 74. Then, the filtered water 11 flows out from the filtering member 40, and the filtered water 25 flows into the downstream space 65 on the opposite side of the partition wall 63.
It flows in. The filtered water 25 drops from the downstream end 51 of the water conduit 61. Then, the filtered water 25 flows from the downstream space 65 through the water guiding portion 61 and is discharged to the outside of the filtered water storage portion 45 due to the energy of the position based on the gravity based on the water level difference Ha and the cohesive force between the water molecules. To be done. When the filtered water 25 flows, the filtered water 11 in the filtered water storage portion 45 also has the energy of the position due to gravity based on the water level difference Ha and the cohesive force between the water molecules, so that the filtering member 4
It will enter the gaps 74 between the fibers 13 from the surface of 0 and naturally flow through the gaps 74 between fibers. By repeating such a flow of water, the filtered water 11 in the filtered water storage portion 45 enters the gaps 74 between the fibers 13 from the entire surface of the filtering member 40 in which the filtered water 11 is immersed in water. By the way, a small group of microorganisms that have been filtered and cannot enter the space between the fibers adheres to the surface of the fiber, and the filtered water 11 naturally flows through the space between the fibers due to a capillary phenomenon. Thereafter, the small population of the microorganisms attached to the surface of the fiber gradually increases as the filtration progresses, and has a microbial colony (for example, a colony of activated sludge) that exhibits a filtering function with a minute gap inside. Form. That is, by this filtration, the activated sludge as suspended solids contained in the filtered water 11 adheres to the surface of the filtration member 40 as a microbial colony. After that, all or part of the water to be filtered 11 is filtered at a place where it enters a minute gap inside the microbial colony, and then naturally flows through the minute gap by a capillary phenomenon, and then the gap 74 between the fibers 13 is formed. Flow naturally through the capillarity.

In this experiment, the filtered water 25 stored in the filtered water storage section 49 is extracted by the pump 73 and then returned to the filtered water storage section 45 and circulated. From the blower 69,
Air 66 is continuously (or optionally or intermittently) supplied to the nozzle 72. When the air 66 is dispersed and supplied from the nozzle 72 into the water 11 to be filtered, the filter member 40 is moved and washed by the large number of bubbles 66a. When the backwashing air 68 is supplied from the blower 69 to the backwashing device 68, the air 66 is supplied to the filtering member 40 through the water guiding section 61. This allows for backwashing air 6
6 flows through the interfiber gaps 74 of the filter member 40 in the direction opposite to the flow of water, and the filter member 40 can be backwashed.
Microbial colonies that have grown too large are washed with air for backwashing 66
Will be smaller or eliminated. Since the air 66 is used as the fluid for backwashing, it is not necessary to use the filtered water 25 that has been treated with care.

FIG. 7 shows the change with time of one string-shaped fiber assembly 43 of the plurality of string-shaped fiber assemblies as an example. FIG. 7A shows a string-shaped fiber assembly 43.
Shows a state in which no solid matter (microorganism colony 75) is attached. In this state, most of the filtered water 11 is at the root portion 43a of the string-shaped fiber assembly 43 and enters the gap 74 between the fibers 13 from the entire surface of the string-shaped fiber assembly 43 that is immersed in water. Filtered. Gap between fibers 7
A small group of microorganisms that cannot be put in 4 adheres to the surface of the fiber 13, and the filtered water 11 naturally flows through the interfiber gap 74 by the capillary phenomenon. The filtered water 25 flows out from the string-shaped fiber assembly 43 and flows into the downstream space 65. As time passes, as shown in FIG. 7B, the string-shaped fiber assembly 4
A small group of microorganisms adheres to the surface of the root portion 43a of No. 3, and this small group of microorganisms gradually increases as the filtration progresses to form a microbial colony 75 composed of activated sludge (adhered solid matter). The string-like fiber assembly 43 surrounded by the microbial colonies 75 is surrounded by the microbial colonies 75 as if it were a pseudo pipe (or honeycomb) composed of a plurality of inter-fiber gaps 74. It has a simple structure. Inside the microbial colony, minute gaps exhibiting a filtering function are formed.
Therefore, the filtered water 11 naturally flows through the gap 74 in the pseudo pipe as shown by the arrow F1 due to the energy of the position due to gravity based on the water level difference Ha and the cohesive force between water molecules. . Further, the water to be filtered 11 naturally flows through a minute gap inside the microbial colony that exhibits a filtering function by a capillary phenomenon.

Then, the filtered water 11 in the filtered water storage portion 45 is in a string shape at a position near the tip of the attached microbial colony 75 and at a position 43b where the microbial colony 75 is not yet attached. Enter the fiber assembly 43. Further, the filtered water 11 is filtered where it enters the gaps 74 between the fibers 13 from the entire surface of the string-shaped fiber assembly 43 that has been soaked in water, and a small group of microorganisms that cannot enter the inter-fiber gaps 74 is the fibers 13. The water 11 to be filtered adheres to the surface and the interfiber spaces 7
4 flows naturally due to the capillarity. Further, the water to be filtered 11 is filtered even in a minute gap inside the microbial colony 75 having a filtering function, and then naturally flows through the minute gap by a capillary phenomenon, and then the interfiber gap 74 is capillared. It flows naturally by a phenomenon. In this way, when the filtration of the filtered water 11 is continued, the adhered microbial colonies 75 gradually move from the root 43a to the tip 43c of the string-shaped fiber assembly 43 as shown in FIG. 7C. It grows and grows. In this state,
The filtered water 11 is the tip 7 of the attached microbial colony 75.
At a position 43b in the vicinity of 5a and where the microbial colony 75 is not yet attached, the string-shaped fiber assembly 4
Enter 3. Further, the filtered water 11 is the string-shaped fiber assembly 4
3 is filtered where it enters the gaps 74 between the fibers 13 from the entire surface soaked in water, and a small group of microorganisms that do not enter the inter-fiber gaps 74 adhere to the surface of the fibers 13 and the filtered water 11 is It naturally flows through the interstices 74 due to the capillary phenomenon. Further, the water to be filtered 11 is filtered even in a small gap inside the microbial colony 75, then naturally flows through this minute gap by a capillary phenomenon, and then naturally flows through the interfiber gap 74 by a capillary phenomenon. It flows.

In this way, the microbial colonies 75 are successively attached around the string-like fiber assembly 43,
The pseudo pipe is a tip portion 43 of the string-shaped fiber assembly 43.
It gradually extends in the direction of c. The filtered water 11 has a gap 74 in the pseudo pipe surrounded by the attached microbial colonies 75, as shown by an arrow F2, in the energy of the position due to gravity based on the water level difference Ha and the cohesive force between water molecules. And flow naturally. Thereby, the filtered water 11
Becomes filtered water 25 and flows into the downstream space 65. Since the filtered water 11 naturally flows through the gaps 74 between the fibers 13 by the capillarity, the adhered microbial colonies 7
The filtration can be continued even if the length of 5 becomes long.

As shown in FIG. 7D, the microbial colony 75 eventually adheres to the tip portion 43c of the string-like fiber assembly 43, and the entire surface of the string-like fiber assembly 43 immersed in water is a microbial colony. Covered with 75. Then, the filtered water 11 is filtered at a place where it enters a minute gap inside the microbial colony 75, then naturally flows through this minute gap by a capillary phenomenon, and then naturally flows through the interfiber gap 74 by a capillary phenomenon. To go. Eventually, when the speed of filtration decreases, the air supply device 67 causes
The air 66 is dispersed in the filtered water 11 and supplied. Then, as shown in FIG. 7E, a large number of rising bubbles 66 are generated.
The string-shaped fiber assembly 43 moves due to a. As a result, the microbial colony 75 that has adhered to the string-shaped fiber assembly 43 and has grown is reduced or removed, and the filtering member 40 is washed. In addition, normally, the air supply device 67
Constantly supplies air 66 into the water to aerate the filtered water 11. Therefore, the attached microbial colony 75
The filter member 40 has been washed before the diamond-shaped fiber aggregate 43 grows to the tip end portion 43c.
Even during this cleaning, the filtered water 11 causes the string-shaped fiber assembly 4 to
3 is filtered where it enters the gaps 74 between the fibers 13 from the entire surface soaked in water, and a small group of microorganisms that do not enter the inter-fiber gaps 74 adhere to the surface of the fibers 13 and the filtered water 11 is It naturally flows through the interstices 74 due to the capillary phenomenon. Therefore, the flow rate of the filtered water 25 does not decrease, and continuous operation can be performed for a long time.

The root portion 43a of the string-shaped fiber assembly 43 is
Microbe colony 75 because there is little movement when washed
Tends to remain attached. Therefore, as shown in FIG. 7F, the backwashing device 68 supplies the backwashing air 66 to the downstream space 65 through the water guiding section 61. Then, the air 66 flows in the direction opposite to the flow of water as shown by the arrow F3, passes through the gap 74 between the downstream space 65 and the fiber 13, and moves outward from the surface of the string-shaped fiber assembly 43. (Here, it is jetted into the water in the filtered water storage portion 45). This makes it possible to reduce or remove the microbial colony 75 attached to the root portion 43a. In this manner, by cleaning the entire string-shaped fiber assembly 43 by using the air supply device 67 and the backwash device 68, the microbial colony 75 that has been attached to the string-shaped fiber assembly 43 and has grown is large. , Can be made smaller or eliminated altogether. Further, there is a proportional relationship between the water level difference Ha and the adhesive force of the activated sludge, and the smaller the water level difference Ha, the weaker the adhesive force. Therefore, as the water level difference Ha is smaller, the attached microbial colony 75 is more likely to drop by the bubbles 66a.

[0044]

[Table 3]

Table 3 shows the experimental results obtained with the water treatment device 46. As shown in Table 3, experiments on the concentration (SS) of suspended solids were carried out when the water level difference Ha was 30 cm and 60 cm. As a result, the concentration of suspended solids (S
It was possible to obtain treated water (filtered water) having a very low concentration of suspended solids (SS) with respect to raw water (water to be filtered) having a large S). Regarding the water level difference Ha, 30 cm from 60 cm
The difference in water level was higher in water treatment capacity.

[0046]

[Table 4]

Table 4 and FIG. 8 which is a graph of this data.
In the figure, changes over time in the flow rate of the filtered water 25 in the water treatment device 46 are shown. The horizontal axis of FIG. 8 is time, and the vertical axis is filtered water 2
A flow rate of 5 is shown. In this experiment, the water level difference Ha is 1
The data is shown for the cases of 0 cm, 20 cm, and 30 cm, and for the case where a pump is connected to the water guiding section 61 and the filtered water 25 is forcibly sucked. The head H of this pump is H = 6.5m
Is. As shown in Table 4 and FIG. 8, the water level difference Ha is 2
In case of 0 cm, 13 hours, 37 hours, 61 hours, 86
After a lapse of time, the backwash device 68 backwashed the filtration member 40. As a result, the microbial colony 75 that had been attached and enlarged was easily reduced or removed, and the flow rate of the filtered water 25 was recovered. Thus, it was confirmed that continuous operation is possible by backwashing the filter member 40 with the backwash device 68 at an appropriate time. An experiment was also conducted in which a pump was connected to the water conduit 61 to forcibly suck the filtered water 25.
However, in this case, the microbial colony 75 adhered to the filter member 40 in a large amount and hard, and the filter member 40 was clogged. Even if the filtering member 40 was washed, it was difficult to remove the adhered microbial colonies 75, and the water treatment capacity was not recovered.

(Third Embodiment) FIGS. 9 and 10 show
It is a figure which shows the 3rd Embodiment of this invention. FIG. 9 is a configuration diagram of the water treatment device 80, and FIG. 10 is a diagram showing the filtration member 40 and the filtration member support portion 85 used in the water treatment device 80. 10A and 10B are a plan view, a front view, and
10C is a cross-sectional view taken along line XX of FIG.
As shown in FIG. 9 and FIG. 10, the water treatment device 80 is for discharging the aeration tank 82 as the filtered water storage part, the string-shaped filtering member 40, and the filtered water 25 flowing out from the filtering member 40. It comprises a filtered water discharge means 83 and a cleaning means 84 for cleaning the filtering member 40. The filtered water 11 is stored in the aeration tank 82, and the entire filtering member 40 provided in the aeration tank 82 is immersed in the filtered water 11. As a result, the filtered water 11 is filtered where the filtered water 11 enters the gaps 74 (FIG. 7) between the fibers 13 from the entire surface of the filtering member 40 immersed in the water, and the microorganisms that cannot enter the interfiber gaps 74 are filtered. The small group adheres to the surface of the fiber 13, and the filtered water 11 naturally flows through the interfiber gap 74 by a capillary phenomenon. After that, the small population of microorganisms attached to the surface of the fiber 13 gradually increases as the filtration proceeds, and forms a microbial colony 75 (FIG. 7) that has a minute gap inside and exhibits a filtering function. After that, all or part of the water to be filtered 11 is filtered where it enters a minute gap inside the microbial colony having a filtering function, and then naturally flows through the minute gap by capillary action, and then the fiber It naturally flows through the gap 74 between the layers 13 due to the capillary phenomenon. Filtered water 2
5 flows out from the filtering member 40, and the filtered water discharge means 83
Is discharged to the outside of the aeration tank 82.

The filtering member 40 is composed of a collection of a plurality of elongated fiber-shaped fiber assemblies 43. The water level Lb of the filtered water 11 in the aeration tank 82 is always kept constant by a water level adjusting means (not shown). Filtered water discharge means 83
Is provided with a filtering member supporting portion 85, a water guiding portion 86 and a water level difference setting means 87. The filtering member support portion 85 is provided inside the aeration tank 82. The water guiding portion 86 communicates with the filtering member support portion 85 and flows the filtered water 25 flowing out of the filtering member 40 to the outside of the aeration tank 82. The water level difference setting means 87 has a function of setting the water level difference Ha so that the downstream water level La of the filtered water 25 becomes lower than the water level Lb of the filtered water 11.

The filtering member supporting portion 85 supports the filtering member 40 with a partition wall 88 for partitioning the water to be filtered 11. The filtering member support portion 85 includes a plurality of (or one) cylindrical partition walls 8 each having a socket having the same diameter and a circular cross section.
8 and a plurality of (or one) cylindrical sockets 89 of the same diameter for connecting the partition walls 88. Further, the filter member supporting portion 85 is fitted so as to cover the end portion of the partition wall 88 located at the tip end and the end portion of the other partition wall 88 located at the root, and the bottom end cylindrical cap 89a. It has a different-diameter socket 90 having a circular cross section that is fixed to each other. A plurality of (here, eight) slits 91 are formed in each partition wall 88 in a direction parallel to the central axis so as to communicate the outside and the inside of the partition wall 88. The filtered water 11 is aerated on the outside of the partition wall 88.
It is a space stored in 2. The inside of the partition wall 88 is a downstream space 65 through which the filtered water 25 flows.

The filter member 40 is engaged with the slit 91 so as to close the slit 91 and leave no gap. As a result, the filtered water 11 does not pass through the inside of the filtering member 40 and does not short-pass directly to the downstream space 65. The filtering member 40 supported by the partition wall 88 by the slit 91 extends outward from the partition wall 88 and is totally immersed in the filtered water 11. The different-diameter socket 90 has a large-diameter portion 92 fitted to the partition wall 88, a small-diameter outlet pipe 93 provided on the downstream side, and a conical portion 94 connecting the large-diameter portion 92 and the outlet pipe 93. is doing. The outlet pipe 93 is the aeration tank 82.
Is connected to a discharge pipe 95 attached to the. As shown in the drawing, the filtering member 40 can be uniformly backwashed by arranging the outlet member 93 in the horizontal direction and arranging the filtering member supporting portion 85 in a substantially horizontal direction as a whole.

The filtered water 25 flowing out from the filtering member 40 is
Outlet pipe 95 from downstream space 65 through outlet pipe 93
Flow to. A filtered water pipe 96 is provided outside the aeration tank 82. The discharge pipe 95 and the filtered water pipe 96 form a water conduit 86. Filtered water piping 96
Is connected to the discharge pipe 95 and the water level difference setting means 87, and the filtered water 25 flowing through the discharge pipe 95 is supplied to the water level difference setting means 8
Leading to 7. The filtered water pipe 96 is provided with an electric valve 97 that opens and closes in response to a control signal during backwashing work. The cleaning means 84 includes an air supply device 98 and a backwash device 99. The air supply device 98 is provided in the aeration tank 82, and can supply the air 66 dispersed in the filtered water 11 below the filtering member 40. Backwash device 9
9 is a filter member 4 via the flow path of the filtered water discharge means 83.
It is possible to supply backwash air 66 to 0.

The air supply device 98 is an aeration blower 100.
The air 66 supplied by the above is supplied to the plurality of nozzles 72 provided in the lower portion of the aeration tank 82 by the aeration pipe 101. The air 66 is dispersed and supplied from the nozzle 72 into the filtered water 11. By supplying the air 66, the filtered water 11 is aerated, and the filter member 40 is cleaned by the large number of bubbles 66a. Although the air 66 is continuously supplied by the air supply device 98, it may be intermittently supplied. The backwash device 99 is capable of supplying the compressed air 66, and a backwash blower 110, and a backwash pipe 111 for connecting the backwash blower 110 and the filtered water pipe 96.
A motor-operated valve 97 provided in the filtered water pipe 96, a motor-operated valve 112 connected to the backwashing pipe 111 to open and close,
It has a check valve 112a connected to the backwash pipe 111 and a control unit 113. The backwash pipe 111 is connected to the overwater pipe 96 at a supply position 114 for the lower discharge pipe 95 and a supply position 114 for the upper discharge pipe 95, respectively. The air 66 is supplied from the backwash blower 110 through the backwash pipe 111 as needed (or intermittently).
Supplied. The motor-operated valve 97 has a supply position 114 for the air 66.
It is arranged on the more downstream side (downstream side through which the filtered water 25 flows). The control unit 113 includes a backwash blower 110 and an electric valve 9.
7. Control signals are output to the motor-operated valve 112.

The water level difference setting means 87 sets the water level difference Ha to about 1
It is adjustable from 0 cm to about 100 cm.
The water level difference setting means 87 includes a filtered water storage section 49 for storing the filtered water 25, and an adjusting section 115 provided in the filtered water storage section 49 for adjusting the water level difference Ha.
The adjustment unit 115 includes a fixed cylinder 116 that is fixed to the filtered water storage unit 49 and communicates with the filtered water pipe 96, and a movable cylinder 117 that fits in the fixed cylinder 116 and is vertically movable. . The fixed cylinder 116 has a bottomed cylindrical shape and is open at the top. The movable cylinder 117 can be positioned and adjusted at a desired position in the vertical direction with respect to the fixed cylinder 116, and communicates with the inside of the fixed cylinder 116 to open the upper side. The water level difference Ha can be set by moving the moving cylinder 117 in the vertical direction and adjusting the height of the downstream water level La of the filtered water 25. Therefore, the filtered water 25 flowing through the filtered water pipe 96 rises in the fixed cylinder 116 and the movable cylinder 117, overflows at the upper end of the movable cylinder 117, and is stored in the filtered water reservoir 49. The stored filtered water 25 is discharged to the outside as treated water as shown by arrow F4. The position at which the upper end of the moving cylinder 117 overflows is the downstream water level La of the filtered water 25. The adjusting unit 115 may be provided with a height adjustable “cough” so that the filtered water 25 overflows due to the cough.

Next, the operation of the water treatment device 80 will be described. The height position of the upper end of the moving cylinder 117 (that is, the downstream water level La of the filtered water) is the filtered water 1 in the aeration tank 82.
It is lower than the water level Lb of 1. As a result, the downstream space 65 inside the filter member supporting portion 85, the discharge pipe 95,
Filtered water pipe 96, fixed cylinder 116 and movable cylinder 117
Is filled with filtered water 25. In addition, the filtering member 40
Is immersed in the filtered water 11. First, the adjustment unit 115 adjusts the height of the downstream water level La of the filtered water 25 to set the water level difference Ha to an optimum value. Then, the filtered water 11 is filtered where the filtered water 11 enters the gaps 74 between the fibers 13 from the entire surface of the filtering member 40 soaked in water, and the small population of microorganisms that cannot enter the inter-fiber gaps 74 is the fibers 13. The water 11 to be filtered adheres to the surface of the fiber and naturally flows through the interfiber gap 74 by the capillary phenomenon. afterwards,
The small population of microorganisms attached to the surface of the fiber 13 gradually increases as the filtration progresses to form a microbial colony that has a minute gap inside and exhibits a filtering function. After that, all or part of the water to be filtered 11 is filtered where it enters a minute gap inside the microbial colony having a filtering function, and then naturally flows through the minute gap by capillary action, and then the fiber It naturally flows through the gap 74 between the layers 13 due to the capillary phenomenon. When the air 66 is constantly supplied from the aeration blower 100 to the nozzle 72 via the aeration pipe 101, the air 66 is dispersed in the filtered water 11. As a result, the filtered water 11 in the aeration tank 82 is aerated, and the filtering member 40 is washed with the bubbles 66a.
The filtered water 25 flows out of the filtering member 40 and flows into the downstream space 65. Then, the filtered water 25 flows from the downstream space 65 through the discharge pipe 95 and the filtered water pipe 96. Next, the filtered water 25 is transferred to the moving cylinder 11 by the adjusting unit 115.
After overflowing from the upper end of 7 and being stored in the filtered water storage part 49, it is discharged as treated water as shown by arrow F4.

When the microbial colony 75 (FIG. 7) due to activated sludge adheres to the root portion 43a of the string-shaped fiber assembly 43 of the filtration member 40 and becomes too large, the flow rate of the filtered water 25 decreases, so backwashing is performed. Air 66 is supplied. At the time of this backwashing, the control unit 113 outputs a control signal to start backwashing. With this signal, the backwash blower 110 is turned on, and the electric valve 97 in the flow path of the filtered water 25 is operated to close the flow path. Then, the electric valve 112 of the backwash pipe 111 for supplying the air 66 is operated to open the flow path of the air 66. Thereby, the air 66 supplied from the backwash blower 110 passes through the backwash pipe 111, the discharge pipe 95, and the downstream space 65. Then, the air 66 enters the slit 91.
74 between the fibers 13 of the filtration member 40 engaging the
After entering, the water is jetted from the surface of the filtering member 40 into the filtered water 11. The ejection of the air 66 occurs most intensely at the root portion 43a of the filtering member 40. As a result, the root portion 43
The microbial colony 75 (FIG. 7) attached to a is reduced or removed, and the filtration member 40 is entirely washed.

When the backwashing of the filtering member 40 is completed, the control unit 113 outputs a backwashing completion control signal. By this signal, the motor-operated valve 97 is operated to open the filtered water pipe 96, the motor-operated valve 112 is operated to close the backwashing pipe 111, and the backwashing blower 110 is turned off. As a result, the state before backwashing is restored, and the filtered water 11 can be filtered again. In this way, since the filtering member 40 is cleaned by the air supply device 98 and the backwash device 99, the water treatment device 80 can be continuously and automatically operated for a long time.

In the first to third embodiments, in order to cause the filtered water 11 and the filtered water 25 to flow naturally, the energy of the position due to gravity based on the water level difference Ha is used. Instead of the water level difference Ha, the filtered water 25 may be slowly sucked by a pump having a head corresponding to the water level difference Ha. By doing so, the filtered water 11 enters the gap 74 between the fibers 13 from the surfaces of the filtering members 10 and 40 by the energy of the pump and the cohesive force between the molecules of the water, and the inter-fiber gap 74 is formed. It is filtered by naturally flowing to the downstream side. The small population of microorganisms attached to the surface of the fiber 13 gradually increases as the filtration progresses to form a microbial colony that has a minute gap inside and exhibits a filtering function. After that, all or part of the water to be filtered 11 is filtered where it enters a minute gap inside the microbial colony, and then naturally flows through the minute gap by a capillary phenomenon. In addition, when the filtration members 40, 85 are widened to have the slits 64, 91 and the root portion of the filtration member 40 is loosely supported, when the filtration is performed, water is mainly absorbed by the root portion of the string-shaped fiber assembly 43. Filtration is performed. Moreover, when the slits 64 and 91 are narrowed and the root portion of the filtration member 40 is supported in a slightly compressed state to perform filtration, water is collected on the entire surface (the outer peripheral surface and the tip surface) of the string-shaped fiber assembly 43. It is sucked and filtered. These two phenomena have been confirmed by experiments. The string-shaped fiber aggregates 12 and 43 in the present invention include, in addition to those shown in each of the above-described embodiments, thread-like fiber aggregates having a small diameter, fiber aggregates including warp yarns and some weft yarns, and the like. Alternatively, for example, a cloth-like non-woven fabric may be cut into small pieces to form a string-like fiber assembly having a slightly wider width and an elongated shape.
In the second and third embodiments, the case where the entire filtration member 40 is immersed in the water to be filtered 1 has been shown, but even when the majority of the filtration member 40 is immersed in the water to be filtered 11 instead of the whole. Good. Although the case where the partition walls 63 and 88 are cylindrical is shown,
If it is a partition between the filtered water and the downstream space,
It may be flat or polygonal tubular. Also,
Although the case where the filtering member supporting portions 60 and 85 are arranged in a substantially horizontal direction (lateral direction) as a whole is shown, the filtering member supporting portion 6 is shown.
0 and 85 may be arranged in a substantially vertical direction (longitudinal direction) or in a direction inclined with respect to the horizontal direction (oblique direction).

As described above, since the string-shaped filter members 10 and 40 of the present invention are formed into a comb-like shape by assembling a plurality of string-shaped fiber aggregates 12 and 43, clogging is less likely to occur. Further, the string-shaped fiber aggregates 12, 43 can be easily loosened at the time of washing, and the insides of the filtering members 10, 40 can be easily and sufficiently washed to restore the water treatment capacity. Moreover, since the microbial colonies (solid matter) are not forcibly attached to the filter members 10 and 40 but are naturally attached thereto, the filter members 10 and 40 are less likely to be clogged. Therefore, the cleaning means 33, 48, 5
By washing the filter member with 6,84, it is possible to easily reduce or remove the microbial colony that is attached with a weak adhesive force and is growing.

The water to be filtered 11 is filtered from the entire surface of the filtering members 10 and 40 immersed in water into the spaces between the fibers, and a small group of microorganisms that cannot enter the space between the fibers is collected on the surface of the fibers. The adhered water 11 to be filtered naturally flows through the inter-fiber gaps by a capillary phenomenon. After that, the small population of microorganisms attached to the surface of the fiber gradually increases as the filtration proceeds, and forms a microbial colony that has a minute gap inside and exhibits a filtering function. After that,
After the whole or part of the water to be filtered 11 is filtered while entering the minute gaps inside the microbial colony,
The minute gap naturally flows by the capillary phenomenon, and then the interfiber gap naturally flows by the capillary phenomenon. In this way, suspended solids in the filtered water 11 (for example,
(Outer diameter is several μm) is a minute gap inside a microbial colony that exhibits a filtering function (for example, inner diameter is about 1 μm or less)
The suspended solids are filtered by the filtration members 10, 40.
Without passing through the inside of the cord 12,
It adheres to 43 and is removed. As a result, the filtered water 25 is purified and the quality of the water is improved. String-shaped filter member 1
Since the filtration is performed with 0, 40, the filtration area can be made extremely large. In addition, the string-shaped fiber aggregate 12, 4
In No. 3, the water treatment capacity can be freely improved by increasing the filtration area by making it long enough not to be entangled.

In the present invention using the string-shaped filter members 10 and 40, since it is not necessary to settle sludge, the settling tank which has been conventionally required in the activated sludge method or the coagulating sedimentation method is unnecessary. Therefore, it is not necessary to pay close attention to the maintenance of the equipment so that activated sludge does not float up. In addition, the concentration of activated sludge in the aeration tank can be set to the conventional upper limit value (for example, about 5,000 ppm to about 10,000 p
pm) (eg, about 50% to about 10)
It is also possible to increase it by 0%). As a result, the capacity of water treatment can be improved.

Conventionally, in the tap water field, there have been cases where chemicals are injected into raw water and water treatment is carried out by a pressure floating method or the like. On the other hand, in the present invention, since no chemicals are used, it is safe to use filtered water as drinking water and the running cost is low. Conventionally, activated carbon was sometimes used to reduce the COD of raw water, but in the present invention, COD can be reduced at a low cost with a simple configuration without using activated carbon. In the first to third embodiments, the water to be filtered and the filtered water are moved by the energy of the position due to the gravity based on the water level difference and the cohesive force between the water molecules, and no power is used during this period. Absent. Also, there is no need to circulate water. Therefore, compared with the conventional water treatment technology, the power consumption becomes smaller, and the energy consumption of the water treatment device can be reduced. Almost no noise is generated. In the drawings, the same reference numerals indicate the same or corresponding parts.

[0063]

Since the present invention is configured as described above, the filter member is less likely to be clogged, and the filter member can be easily washed to restore the water treatment capacity.

[Brief description of drawings]

FIG. 1 is a diagram for explaining a capillary phenomenon.

FIG. 2 is a diagram showing a first embodiment.

FIG. 3 is a partially enlarged view of a filtering member.

4 to 8 are views showing a second embodiment of the present invention, and FIG. 4 is a schematic configuration diagram when a filtering member is used.

FIG. 5 is a schematic configuration diagram showing a more specific water treatment device.

6 is a sectional view taken along line VI-VI of FIG.

FIG. 7 is a schematic configuration diagram showing a change with time of one string-shaped fiber assembly.

8 is a graph showing a change over time in the flow rate of filtered water in the water treatment device shown in FIG.

9 and 10 are views showing a third embodiment of the present invention, and FIG. 9 is a configuration diagram of a water treatment device.

FIG. 10 is a view showing a filtering member and a filtering member supporting portion used in the water treatment device shown in FIG.

FIG. 11 is a diagram for explaining a related technique of the present invention.

[Explanation of symbols]

10,40 Filtration member 11 Filtered water 12,43 String-like fiber aggregate 13 fibers 19, 47, 57, 83 Filtered water discharge means 20,41,46,80 Water treatment equipment 21,45 Filtered water reservoir 25 filtered water 33,48,56,84 Cleaning means 50 pipes (water conduit) 54,66 Air (fluid) 55,67,98 Air supply device 60,85 Filter member support 61,86 Water transfer section 62,87 Water level difference setting means 63,88 Partition wall 68,99 Backwash device 74 Gap between fibers 75 Microbial colonies 82 Aeration tank (filtered water storage part) Ha water level difference La Downstream water level of filtered water Lb Water level of filtered water

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C02F 3/12 B01D 29/38 580A

Claims (6)

[Claims] 1. A filter member for storing filtered water in a filtered water storing part, wherein a part or almost all of a filtering member provided in the filtered water storing part and composed of a plurality of long and narrow string-like fiber aggregates is provided. By immersing in the water to be filtered, the water to be filtered is filtered where the water to be filtered enters the gaps between the fibers from the entire surface of the filtering member immersed in the water, and the water to be filtered of the microorganisms that cannot enter the gaps between the fibers. A small group adheres to the surface of the fibers, the water to be filtered naturally flows through the interfiber gaps by a capillary phenomenon, and then the small group of the microorganisms adhered to the surface of the fibers, as the filtration progresses. Gradually grow to form a microbial colony that has a minute gap inside and exhibits a filtering function, and thereafter, all or part of the water to be filtered is in the minute gap inside the microbial colony. Where to enter After being filtered by, the micro gap naturally flows through the capillarity, and then the inter-fiber gap naturally flows through the capillarity, and the filtered water flows out from the filtering member and the filtered water storage part. The water treatment method utilizing the capillarity, which is characterized in that the water is discharged to the outside. 2. A filtered water storage part for storing filtered water, and a plurality of long and narrow cord-shaped fiber aggregates which are provided in the filtered water storage part and are partially or almost entirely immersed in the filtered water. A filtering member configured by a body assembly, a filtered water discharging unit for discharging filtered water flowing out from the filtering member, and a cleaning unit for cleaning the filtering member, the filtered water is A small group of microorganisms that are filtered from the entire water-immersed surface of the filtering member into the gaps between the fibers and do not enter between the fiber gaps adhere to the surface of the fibers, and the water to be filtered is It naturally flows through the gaps by capillarity, and then the small population of the microorganisms attached to the surface of the fibers gradually increases as the filtration progresses, and has a minute gap inside to exert a filtering function. Microbial colony After that, all or part of the water to be filtered is filtered where it enters the minute gap inside the microbial colony, and then naturally flows through the minute gap by capillarity, and then the fiber. The filtered water naturally flows through the interstices by a capillary phenomenon, and the filtered water flows out from the filtering member and is discharged to the outside of the filtered water storage part by the filtered water discharging means. A water treatment device that uses the capillary phenomenon. 3. The filtering member is substantially entirely immersed in the filtered water, and the filtered water discharging means is provided inside the filtered water storage section and is connected to the filtered water. A filtering member supporting part having a partition wall and supporting the filtering member with this partition wall, and the filtered water flowing out from the filtering member communicating with the filtering member supporting part to the outside of the filtered water storage part. The water guide part for flowing, and the water level difference setting means for setting the water level difference so that the downstream side water level of the filtered water is lower than the water level of the filtered water. A water treatment device utilizing the described capillarity. 4. The air supply device provided in the filtered water storage part so that the cleaning means can disperse and supply air into the filtered water below the filtering member, and the filtered water discharge. A structure capable of supplying a fluid for backwashing to the filtering member via the flow path of the means, and a backwashing device for reducing or removing the microbial colonies that have become too large, The water treatment device utilizing the capillarity according to claim 2 or 3. 5. The water treatment apparatus utilizing capillary action according to claim 4, wherein the backwashing device supplies air or water for backwashing to the filtering member. 6. The water treatment utilizing capillary action according to claim 3, wherein the water level difference setting means can adjust the water level difference within a range of about 10 cm to about 100 cm. apparatus.