JPH11267410A - Filter device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a filter to reduce the frequency of washing against clogging and to perform stably and uniformly the feeding of water to be treated to a filter medium bed. SOLUTION: This filter device is provided with a filter medium bed 7 packed with filter medium and a supporting part 6 for supporting the filter bed 7 installed in a filter tank 1. A supporting bed 6a of the supporting part 6 is formed by a bed packed with at least two kinds of granular materials for the different kinds, respectively in which the materials are almost spherical as the upper layer and are almost flat as the lower layer and then, the granular materials in the supporting bed 6a are fluidized when water to be treated passes through the supporting bed 6a. Further, a relaxing part 6b thereof shields a part of the fed water to be treated to relax a change in the flow velocity of the water to be treated when it passes through the supporting bed 6a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a purifying apparatus for purifying water of sewage, rivers, lakes and marshes, and more particularly to a filtering apparatus utilizing upward flow fluidized bed filtration.

[0002]

2. Description of the Related Art Generally, in a purifying apparatus for purifying water such as water and sewage, rivers, lakes and marshes, water to be treated is directed upward through a flowing filter medium filled in a filtration tank. A method called a fluidized bed that removes organic pollutants, algae, or hard-to-decompose specific substances in the water to be treated by a biological reaction of microorganisms or a physicochemical adsorption action of the filter medium is called water. Used as part of the processing process.

[0003] In a fluidized bed, a filter medium filled in a filtration tank is
It is fluidized and brought into contact with the water to be treated. As a method of fluidizing the filter medium, a method of performing water filtration at a flow rate equal to or higher than the flow rate at which the filter medium fluidizes is generally used.

[0004] Here, filtration means not only a method of separating and removing a suspension in the water to be treated by a physical action, but also a chemical and biological action of a filter medium filled in a filtration layer. And those for purifying the water to be treated.

[0005] The use of a fluidized bed has the following advantages.

In the fixed bed filtration, the filter medium layer is fixed and comes into contact with the water to be treated in order from the inlet side, so that the load of the water to be treated concentrates only near the inlet of the filter medium layer, and the entire filter medium layer is effectively used. On the other hand, in the case of fluidized bed filtration, since the filter medium is flowing, the water load to be treated is dispersed throughout the filter medium layer, so that the entire filter medium layer can be effectively used. Good contact efficiency with the water to be treated.

[0007] In the so-called fixed bed filtration, clogging due to the suspended matter occurs, and it is necessary to frequently perform the washing operation of the filter medium. On the other hand, in the fluidized bed, the filter medium layer due to the suspended matter in the water to be treated is used. Since the clogging does not occur, the operation can be performed without performing cleaning for a long time.

[0008] In particular, in the case of using a biological treatment, in a fluidized bed system, the biofilm is peeled off in a timely manner due to the flow of the filter medium, thereby preventing excessive thickening of the biofilm and maintaining a constant biofilm thickness at all times. it can.

An example of a fluidized bed filtration apparatus is described in, for example, "Water", Vol. 34, No. 2, (1992). The filtration layer is a lower space that guides the water to be treated from the bottom to the filtration layer, and a rectifying device that is disposed immediately above, and a dispersed gravel layer that is disposed immediately above, and a filter medium layer that is disposed thereon. It is composed of

The water to be treated is introduced into the lower space, passes through a rectifier and a dispersed gravel layer, contacts a filter medium with a fluidized filter medium layer, is purified, and is disposed at an upper portion of the filtration tank. It is discharged as treated water from the collecting weir.

[0011] Among them, the rectifier and the dispersed gravel layer are:
It is arranged to ensure a uniform flow of the water to be treated at the bottom of the filter medium layer, whereby water is uniformly supplied to the filter medium layer at the inlet of the filter medium layer, and thus the entire filter medium layer is evenly distributed. Flow is achieved.

Further, the dispersed gravel layer has a great role of supporting the filter medium of the filter medium layer so as not to fall down.
In general, the smaller the filter medium and the smaller the specific gravity, the more easily the fluidized medium is fluidized. As a conventional example, activated carbon having a particle size of about 1 mm is often used.

In this case, in order to support the filter medium, a structure in which a gravel layer or the like is disposed below the filter medium layer so that the filter medium layer does not fall down is essential as in the above example. Generally, in order to support the filter medium, at least the uppermost layer of the gravel layer must be loaded with gravel having a particle size of about 2 to 4 times the particle size of the filter medium. A gravel layer having a particle size distribution of about 5 mm is required at least at the top of the gravel layer.

[0014]

However, the above-mentioned prior art has the following problems. In other words, according to the above-described conventional technology, when there is a suspension in the water to be treated,
The suspended matter is gradually retained in the gravel layer, or even if there is no suspended matter in the water to be treated, the dissolved organic matter in the water causes the assimilation and metabolic reaction of microorganisms attached to the gravel layer. Suspensions accumulate.

[0015] Therefore, if water is continuously supplied for a long period of time, the gravel layer is clogged, causing a large pressure loss.

Although the above-mentioned support structure exists in the fixed bed filtration method and the same problem occurs, in the fixed bed filtration method, in general, the filter medium layer is preceded by clogging of the gravel layer. Since the clogging occurs, the gravel layer is also washed when the filter medium layer is washed, so that the clogging of the gravel layer did not cause much problem.

However, in the fluidized bed filtration method, the filter medium layer does not become clogged even if water is continuously supplied for a long period of time and does not cause an increase in pressure loss. When is applied, as described above, the excessive thickening of the biofilm is automatically suppressed, and in that respect, the necessity of washing the filter medium is reduced.

For this reason, the necessity of cleaning the gravel layer is relatively greater than that of the filter medium layer. If water is continued for a long time without washing the gravel layer, the pressure loss will increase in the gravel layer,
As a result, in the case of unnecessary pump power due to pressure loss or equal flow rate filtration, the pump rotation speed is adjusted according to the change in pressure loss, or a flow control valve is attached to the inflow pipe of the water to be treated, and the There arises a problem that control and work such as adjustment are required.

Further, if water is continuously supplied for an excessively long period of time, there arises a problem that a required amount of water cannot be secured at times due to clogging of the gravel layer. To avoid this, the support layer is frequently washed. Generally, as the washing, air is injected from the lower part of the filtration layer, or
For example, a method of injecting air while passing water is used.

In the case of such washing using air, even if it is desired to wash only the gravel layer supporting the filter medium layer, that is, only the support layer, the air having washed the support layer passes through the filter medium layer as it is, Inevitably, the filter medium layer located above the support layer is also washed, and when the fluidized bed filtration method is used for biological treatment, unnecessary separation of the biofilm on the surface of the filter medium is caused. , Leading to deterioration of processing performance.

Further, even in the case where the filter medium is used for physicochemical adsorption, unnecessary washing of the filter medium causes unnecessary wear of the filter medium due to rubbing of the filter medium, or outflow of the worn filter medium.

Further, since the filter medium of the filter medium layer is usually fluidized in passing water, it can be easily washed with a small amount of air.
It becomes necessary to provide a large blower only for cleaning the support layer. Above all, the filtration operation temporarily interrupts the filtration process, and frequent cleaning itself is disadvantageous for the entire apparatus.

As a method for avoiding this, a method of eliminating the supporting gravel layer and using a repose angle of the filter medium particles to prevent the filter medium from falling is described in, for example, JP-A-08-243575. However, in this case, when the operation is on or off, the filter medium falls to the lower part, and even during normal water supply, the filter medium slightly drops to the lower part of the filter tank.
A means for pulling out the dropped filter medium or returning it to the filter medium layer is required.

In this method, the operation is erroneous,
When the pressure at the lower part of the filtration tank becomes lower than the pressure of the filter medium layer, there is a problem that a large amount of the filter medium falls to the lower part of the filtration tank.

Further, the lower part of the filtration tank must always be at a higher pressure than the filter medium layer. Therefore, when foreign matter is mixed in the lower space and the pressure is lowered, the lower space is easily opened to remove the foreign matter. There is a problem that maintenance cannot be performed. As described above, the problem of clogging and washing of the support layer adversely affects the filter medium, and frequent washing or providing a large blower only for washing the support layer is an advantage of a fluidized bed. Also, when supporting using the angle of repose, the filter media falls to the lower part of the filter tank, so the filter media must be returned to the filter media layer, or the equipment must be operated and maintained.
Large restrictions.

Further, as another means for solving the above-mentioned problem of clogging, a method of eliminating the rectifying structure and the support layer in the filtration tank and supplying the water to be treated directly to the bottom of the filter medium layer by piping can be considered.

In this case, the problem of clogging of the support layer does not occur due to the elimination of the support layer. Conversely, since there is no rectifier and no support layer, water flows through the cross-sectional area of the filtration tank, which is the pipe outlet. Since it is supplied to the filter medium layer in an uneven form from an extremely small place compared to, the filter medium layer does not flow evenly,
In severe cases, dead water areas where water does not flow at all are formed, and the water to be treated flows with a short-circuit of a part of the filter medium layer, and the entire filter medium layer is not effectively used, and as a result, the performance as a purification device There is a problem that the reduction is caused.

An object of the present invention is to solve the above problems.
It is an object of the present invention to provide a filtration device that can reduce the frequency of washing for clogging and can supply stable and uniform water to be filtered to a filter medium layer.

[0029]

In order to achieve the above object, the present invention provides a filter medium layer filled with a filter medium and a support portion disposed below the filter medium layer and supporting the filter medium layer. In a filtration device having a filtration tank for passing and filtering the water to be treated upward, and a water supply section for supplying the treatment water from the lower part of the filtration tank through the support section and supplying the filtration medium layer to the filtration medium layer, The support section has a support layer formed of a layer in which at least two or more types of granular materials are individually filled, and the shape of the granular material of each layer of the support layer is closer to a sphere as the upper layer and flatter as the lower layer. It is characterized by being close to a simple shape.

Further, as another feature of the present invention, each granular material of the support layer flows in a range from a substantially uppermost layer to a lowermost layer of the support layer.

Another feature of the present invention is that water to be treated is supplied upward from a lower portion of a filtration tank provided with a filter medium layer filled with a filter medium and a support portion for supporting the filter medium layer. In a filtration device that passes a support portion and filters the water to be treated with the filter medium layer, the support portion disperses the supplied water to be treated and passes the water to the filter medium layer, and the filter medium layer is at a lower portion. A support layer formed of at least two or more types of granular materials that support not to fall, and a part of the supplied water to be treated is shielded, and the flow rate of the water to be treated when passing through the support layer And a mitigation unit for reducing fluctuation.

Another feature of the present invention is that a filter medium layer filled with a filter medium and a treated water supply means for supplying treated water to the filter medium layer are provided inside, and the treated water is passed upward. In a filtration device having a filtration tank for filtering, the treated water supply means supplies the treated water sent from a treated water supply pipe disposed in a lower layer in the filter medium layer to a lower layer in the filter medium layer. An opening for passing the water to be treated is provided on a side surface surrounding a bottom surface that is larger than a cross section of the treated water supply pipe toward the bottom of the filtration tank of the treated water supply means. It is being done.

Another feature of the present invention is that a filter medium layer filled with a filter medium and a treated water supply means for supplying treated water to the filter medium layer are provided inside, and the treated water is subjected to upward filtration. In the filtration device having a filtration tank, the water-to-be-treated supply means supplies the water to be treated, which is disposed in a lower layer in the filter medium layer and is sent from a water-to-be-treated supply pipe, to a lower layer in the filter medium layer. An opening through which the water to be treated passes is provided on a side surface surrounding a bottom surface that is larger than a cross section of the water to be treated supply pipe toward the bottom of the filtration tank of the water to be treated supply means. And a pedestal is provided at the lower part of the filtration tank for the treated water supply means to hold its position in the filter medium layer and guide it to a predetermined position.

Another feature of the present invention is that a filter medium layer filled with a filter medium and a treated water supply means for supplying treated water to the filter medium layer are provided inside the filter medium layer so that the treated water flows upward. In a filtration device having a filtration tank for filtering, the treated water supply means supplies the treated water sent from a treated water supply pipe disposed in a lower layer in the filter medium layer to a lower layer in the filter medium layer. An opening for passing the water to be treated is provided on a side surface surrounding a bottom surface that is larger than a cross section of the treated water supply pipe toward the bottom of the filtration tank of the treated water supply means. And a rectifying plate for equalizing the upward flow of the water to be treated is provided above the water supply means.

Another feature of the present invention is that a filter medium layer filled with a filter medium, a support layer for supporting the filter medium layer, and a treated water supply means for supplying treated water to the filter medium layer are provided inside. In a filtration device having a filtration tank for passing and filtering the water to be treated upward, the support layer is formed of a layer in which at least two or more types of particulate matter are individually filled, and the means for supplying water to be treated is Supplying the water to be treated, which is arranged in the lower layer in the filter medium layer and sent from the water supply pipe to the lower layer in the filter medium layer, toward the bottom of the filtration tank of the water to be treated supply means. An opening for allowing the water to be treated to pass through is provided on a side surface surrounding a bottom surface that is larger than the cross section of the water to be treated supply pipe.

According to the present invention, the support layer is formed as a layer in which at least two or more types of granular materials are each filled with at least two types, each of which is closer to a spherical shape as the upper layer and closer to a flat shape as the lower layer. Water is dispersed and passed through the filter medium layer, and the filter medium layer is supported so as not to fall to the lower part. Each granular material of the support layer flows in a range from substantially the uppermost layer to the lowermost layer of the support layer when the water to be treated passes. In addition, the relieving section shields a part of the supplied water to be treated, and reduces fluctuations in the flow velocity of the water to be treated when passing through the support layer.

The water-to-be-treated supply means supplies the water to be treated, which is disposed in the lower layer of the filter medium layer and is sent from the water supply pipe, to the lower layer of the filter medium layer. The opening provided on the side surface surrounding the bottom surface, which is opened to be larger than the cross section of the water supply pipe toward the bottom of the filtration tank of the water supply means, allows the water to pass through.

As described above, the flow of the granular material makes it difficult for the support layer to be clogged, and also alleviates the fluctuation of the flow velocity, whereby the water to be treated can be stably supplied to the filter medium layer. Can be made to flow uniformly.

Further, since the water to be treated is supplied through a large number of openings provided in the means for supplying the water to be treated, the supply of the water to be treated to the bottom of the filter medium layer is stable and uniform, and the filter medium layer is formed. Uniform flow can be enabled.

Further, a pedestal is provided at the lower part of the filtration tank for holding the position of the treated water supply means in the filter medium layer and guiding the treated water to a predetermined position. Can be performed without removing the filter medium filled in the filtration tank, and maintenance can be performed very easily.

In addition, since a straightening plate for equalizing the upward flow of the water to be treated is provided above the means for supplying the water to be treated,
The to-be-treated water supplied to the filter medium layer from the to-be-treated water supply means flows more uniformly upward.

[0042]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing a first embodiment of a filtration device according to the present invention. In the filtration device shown in FIG. 1, reference numeral 1 denotes a fluidized bed type filtration tank for passing and filtering water to be treated upward, 2 denotes a supply pipe for supplying the water to be filtered to the filtration tank 1, and 3 denotes a pipe for cleaning. An air supply pipe for supplying air to the air, a diffusion hole 3b for blowing out cleaning air into the lower space, a treatment water inflow pipe 2 and a cleaning air supply pipe 3
Is disposed in the lower space, 5 is a rectifying unit, 5a is a rectifying device,
Reference numeral 6 denotes a support portion, 6a denotes a support layer, 6b denotes a relaxation portion, 7 denotes a filter medium layer filled with a filter medium, 8 denotes an upper water collecting device, and 10 denotes an air supply means for sending cleaning air.

The rectifier 5 is for uniformly supplying the water to be treated to the filter medium layer 7. The support layer 6 serves to disperse the water to be treated that has passed through the rectification device 5 and at the same time support the filter medium layer 7 so that it does not fall down. The air supply means 10 is used for cleaning the rectifying section 5, the support layer 6, and the filter medium layer 7.

In the filtration device shown in FIG. 1, the water to be treated is sent to the lower space 4 through the treated water inflow pipe 2, and thereafter,
It passes through the rectifier 5a and the support layer 6a to reach the filter medium layer 7. The filter medium layer 7 is in a fluid state, and the water to be treated is purified by the contact between the filter medium of the filter medium layer 7 and the water to be treated, and is discharged from the upper water collecting device 8 as water to be treated or sent to the next treatment.

FIG. 2 is a perspective view of the support section 6, FIG. 3 is a perspective view of the rectifying section 5, and FIG.

The air supply pipe 3 has a comb shape in order to supply air to the entire cross section of the filtration tank 1, but its shape is not particularly limited. In the present embodiment, the rectifying unit 5 is a perforated plate, and the water to be treated flows over the entire cross section by narrowing the flow path and applying a pressure loss above and below the perforated plate.

The structure of the rectification unit 5 may be any as long as it acts so that the water to be treated flows uniformly over the entire cross section.
For example, a slit strainer or the like may be used, and the structure is not particularly limited.

The rectifying section 5 and the supporting section 6 are divided into a lattice shape, and half of the area is shielded by the shielding area 5b.

The easing portion 6b located above the shielding area allows the water to be treated supplied from the support layer 6a to spread evenly in the cross section of the filter medium layer 7, and that the upper part of the shielded area stagnates and the filter medium flows. To prevent stagnation.

The relief section 6b is provided in the filtration tank 1 in the water flowing direction.
By gradually increasing the cross-sectional area and gradually decreasing the flow velocity, fluctuations in the flow and expansion of the support layer 6a due to fluctuations in the water flow rate are alleviated. To return to the place.

FIG. 5 is an enlarged view of the support layer 6a. The support layer 6a is formed of a layer filled with at least two or more types of granular materials. The uppermost granular material is small enough to support the filter medium immediately above, and the lowermost granular material is a rectifying unit. 5 must be large enough not to fall.

In FIG. 5, for the sake of simplicity, only a part of the granular material is shown, but actually, three layers are filled in a layered manner. Each layer is larger in the lower layer as long as the layer directly above it can be supported.

The shape and specific gravity of the granular material in each layer must be determined as follows.

When water flows through the inside of the support layer 6a, each granular material is fluidized by its flow velocity.

The upper layer of the support layer 6a is closer to a sphere, and the lower layer is flatter.

A description will be given below using a specific example. At a filtration speed of 2 mm / s, the average particle size is 0.5 mm, the specific gravity is 1.33,
It is assumed that fluidized bed filtration is performed using activated carbon having a shape factor of 0.7 as a filter medium. On the other hand, first, half of the area of the support part 6 and the rectification part 5 is shielded as shown in FIG.

The rectifying section 5 is a perforated plate having a diameter of 7 mm. At this time, the filtration speed of the support part 6 is about twice, 4 mm / s
Becomes

On the other hand, the support layer 6a is composed of three layers,
A spheroid with a specific gravity of 1.1 and a particle diameter of 2 mm filled in the uppermost layer, and a spheroid with a specific gravity of 1.1 and a particle with a diameter of 5 mm crushed in half on one side. The lowermost layer is composed of spheroidal particles having a specific gravity of 1.1 and a sphere having a particle diameter of 11 mm and a height of 3 mm and crushed on one side.

In view of the size of the granular material, the uppermost layer supports the filter medium layer 7 and the lowermost layer does not fall from the perforated plate. If each layer is made of the same shape and different particle size, the minimum flow velocity required to fluidize each layer of the support layer 6a will be greatly different for each layer, and the largest granular material in the lowermost layer will flow. When the water is passed through at the filtration rate necessary to make
It expands and causes mixing with the filter medium layer 7.

By making the lowermost layer flatter,
Fluid can be fluidized at around 4 mm in the entirety from the uppermost layer to the lowermost layer. As the particulate matter of the support layer 6a is fluidized, the retained suspension is discharged to the upper filter medium layer 7.

Further, since the flow rate gradually decreases by providing the relaxation portion 6b, even if there is a slight variation in the flow rate, the support layer 6a expands as a result of fluidization, and the height of the flow rate is reduced. , The effect of the flow velocity is reduced. Further, in each layer having the above relationship, the lower layer has a higher sedimentation velocity, so that the layers are not exchanged even when fluidized.

In the above embodiment, the rectifying section 5, the shielding area of the support section 6, and the relaxation section 6b are eliminated, and the support layer 6a
And the same cross-sectional area of the filter medium layer 7, without increasing the flow velocity in the support layer 6 a compared to the flow velocity of the filter medium layer 7,
By using a support layer 6a made of a lighter-weight granular material,
The support layer 6a may be fluidized, but in this case, care must be taken so that the sedimentation speed of the granular material of the support layer 6a is sufficiently higher than the sedimentation speed of the filter medium of the filter medium layer 7, ,
Specific gravity must be determined.

When the difference between the two is small, the support layer 6a
This is because when the suspension adheres to the granular material and the effective specific gravity of the granular material decreases, the vertical relationship between the filter medium layer 7 and the support layer 6a may be reversed.

The filtration speed during normal water flow may be set lower than the speed at which the support layer 6a is fluidized, and may be, for example, higher than the speed at which the support layer 6a is fluidized periodically for a certain period of time. Accordingly, the support layer 6a is fluidized only when the flow rate is temporarily increased, and the suspended solids are discharged. Thus, the clogging of the support layer 6a can be avoided. Abrasion of the granular material of the support layer 6a can be reduced.

It is also possible to operate at a filtration speed that is slightly lower than the speed at which the support layer 6a is fluidized when the water is passed normally. In this case, the suspension suppresses the gap between the support layers and reduces the flow rate required for fluidizing the support layer 6a.
The granules of a fluidize spontaneously and discharge the suspension.

The experimental results relating to the present embodiment are shown below. The properties of the granular materials used in the experiment are as follows.

Material Nylon, specific gravity 1.2 Shape Top layer, cylinder 2 mm in diameter, 2.0 mm in height Intermediate layer, cylinder 5 mm in diameter, 2.5 mm in height Bottom layer, cylinder 10 mm in diameter, 3.0 mm in height Each of the three layers is filled into a 70 mm layer.

At this time, the flow rate and pressure loss in the support layer,
FIG. 25 shows the relationship with the expansion coefficient of the entire support layer. In FIG. 25, the solid line shows the relationship between the water passing speed and the pressure loss, and the dotted line shows the relationship between the water passing speed and the expansion rate.

Thus, the water flow rate of the support layer was 15 mm / s.
To the extent, the pressure loss of the support layer became constant with respect to the flow rate, indicating that the whole granular material was in a fluid state. The expansion rate is about 1.2 at a flow velocity of 20 mm / s, which indicates that excessive expansion and flow are suppressed.
When the granular material was filled upside down, passed through water, and fluidized, it was confirmed that the upper and lower layers were correctly replaced. When the support layer is composed of these three types of granular materials, for example, when applied to a filtration tank having a filtration speed of 2 mm / s, 90% of the area of the support portion 6 and the rectifying portion 5 is shielded, thereby supporting the support portion. By setting the water flow rate to 20 mm / s, the support layer can be fluidized at a filtration rate of the filtration tank of 2 mm / s.

FIGS. 6 to 8 show the first embodiment in which the distribution and the ratio of the shielding area of the supporting portion and the rectifying portion are changed.

In FIG. 8, reference numeral 33 denotes a cleaning air supply pipe;
33a is a diffuser hole for blowing cleaning air into the lower space, in FIG. 7, 35 is a rectifying unit, 35a is a rectifying device,
In FIG. 7, 36 is a support portion, 36a is a support layer, 36b
Is a relaxation part, and regarding the configuration of the filter tank, the filter medium layer, etc.,
It is the same as FIG.

In the present embodiment, the distribution of the shielding area and the ratio of the shielding area to the cross-sectional area of the filter medium layer are determined in consideration of uniform flow of the filter medium layer above the support layer, structural strength, ease of manufacture, and the like. What is necessary is just to determine and it is not specifically limited.

FIGS. 9 and 10 show a modification of the first embodiment in which the configurations of the support portion and the rectification portion are changed.

In FIG. 9, a plurality of vertically communicating channels are provided in the supporting portion 56.
The upper part of 8 is a deceleration part 57 whose cross-sectional area is enlarged and which functions similarly to the relaxation part 6b of FIG. A support rectifier 10 in which a support layer and a rectifier are integrated in a cylindrical flow path.
2 has been inserted. The upper portion of the speed reduction portion 57 is covered with a net 59.

FIG. 11 is an enlarged view of the support rectification device 102. In the support rectifier 10, at least two or more types of granular materials are filled in a cylindrical casing 103, and a perforated plate 52 is attached to the bottom of the casing 103.

The support rectifier 102 inserted into the cylindrical flow path of the support portion 56 plays the same role as the support layer 6a in FIG. 2 and the rectifier 5a in FIG. Similar to the above example, at the time of passing water, each of the particles 112 and 113 is fluidized by the flow velocity, and each of the particles has a spherical shape near the upper layer and a flat shape as the lower layer.

The perforated plate 52 may be of any type as long as it allows the water to be treated to flow uniformly over the entire cross section of the filter medium layer, as in the above-described example. For example, a slit strainer may be used. Not limited.

The support rectifying device 102 is inserted into a cylindrical flow channel 58 which is a part of a flow channel communicating with the upper and lower portions of the support portion.
For example, it is fixed by the fixing portion 105 by a bolt. In the mesh 59 covering the upper part of the flow path, the gap is larger than the diameter of the filter medium and smaller than the granular material filled in the support sizing apparatus 102, and the filter medium can freely enter and exit.
The particulate matter filled in the support cannot pass through.

The net 59 in FIG. 9 is for preventing the particles from overflowing from the support rectification device 102 in which the flow velocity becomes higher than usual when the flow velocity becomes uneven in each support rectification device 102. is there. In the net 59, since the filter medium can freely enter and exit, the net is
Clogging is unlikely to occur because it constantly rubs against the filter medium.

The effect of adopting the first embodiment of the present invention will be described below.

By providing a support layer composed of a plurality of granular materials having a more spherical shape as the upper layer, the upper layer of the support layer can be fluidized from the upper layer to the lower layer at the same flow rate without violently flowing and expanding. it can.

Further, by increasing the flow rate of water through the support layer as compared with the flow rate of water through the filter medium layer, by providing a relief section or a deceleration section in which the cross-sectional area of the flow path gradually increases in the upper portion of the support section. In addition, fluctuations in the flow and expansion of the support layer due to fluctuations in the flow velocity can be reduced, and the support layer can flow stably.

Further, by flowing the support layer, clogging by the suspension is less likely to occur. This reduces the need for cleaning the support layer, and can reduce the frequency of air cleaning, even when required.

Further, as compared with the case where a gravel layer is used, the support layer is more likely to be fluidized, so that the amount of washing air can be reduced, and it is not necessary to provide a large air supply means. Also, there is no drop of the filter medium. Further, the filter medium does not fall below the support layer or flow backward. In addition, the water to be treated is uniformly supplied to the bottom of the filter medium layer by the rectifying support structure including the support section, which is disposed over the entire cross section of the filtration tank, and the filter medium layer flows uniformly.

FIG. 12 shows a second embodiment according to the present invention.

In the filtration device shown in FIG. 12, reference numeral 61 denotes a fluidized bed filtration tank for passing and filtering water to be treated upward, and reference numeral 62 denotes an activation treatment target for feeding the water to be filtered into the filtration tank 61 when the filtration tank 61 is activated. A water supply pipe 62 a is a start-up treated water supply hole for blowing out the treated water into the filtration tank 61 at the time of start-up.
Is an air supply pipe for supplying air for cleaning, 63
a is a diffuser hole for blowing out cleaning air, 65 is a treated water supply means for supplying treated water to the filtration tank at the time of steady flow, and 65a is cut at a lower side surface of the treated water supply means 65. Opening 65b is a check valve for preventing backflow of the water to be treated, 6b
Reference numeral 6 denotes a starting water supply pipe 62 and a cleaning air supply pipe 63.
A drain pipe for draining water from the filtration tank 61; 67, a filter medium layer filled with the filter medium; 68, an upper water collecting device; and 69, a cover for washing air. Baffle plate for preventing the water from entering the treated water supply device, 70
Is an air supply means for sending cleaning air.

In this filtration device, in the steady state, the water to be treated is supplied from the water supply device 65 and supplied to the filter medium layer 67 from below the filter medium layer 67. The filter medium layer 67 is in a fluidized state due to the passage of the water to be treated, and when the filter medium of the filter medium layer 7 comes into contact with the water to be treated, the water to be treated is purified and discharged from the upper water collecting device 68 as treated water. .

The air supply pipe 63 is for supplying air to the filter layer for cleaning the support layer 66 and the filter medium layer 67. For example, the air supply pipe 63 has a comb-like shape as used in the first embodiment. The pipe may have a diffuser hole, but the shape is not particularly limited.

The washing may be performed temporarily when, for example, a biological film in biological treatment or a suspended matter in the water to be treated excessively adheres to the filter medium and the support layer 66.

Further, when the filtration device is once stopped and restarted, the filtration medium flows backward to the treatment water supply means 65 for some reason, or the treatment water supply means 62 is used for the treatment water supply means 65. When the filter medium in the vicinity of the outlet becomes compact and water cannot be supplied from the water-to-be-treated supply means 65, the water to be treated is once sent from the treated water-to-be-started supply pipe 62 to bring the filter medium layer into a fluidized state, and This eliminates the consolidation near the outlet of the supply means 65 and smoothly discharges the filter medium that has flowed back to the treated water supply means 65.

The starting water supply pipe 62 is provided with a support layer 66.
Thus, the filter medium is separated from the filter medium, and water is supplied upward to the filter medium via the support layer 66. Therefore, there is no problem of backflow or compaction of the filter medium, and the filter medium can easily flow.

For the water to be supplied to the starting water supply pipe 62 and the water supply means 65, the same supply means such as a pump may be used, or separate supply means may be prepared.

Once the passage of water from the treated water supply means 65 becomes possible, the supply of water from the starting treated water supply pipe 62 is stopped. The starting water supply pipe 62 is used when it becomes difficult to pass water through the water supply means 65 at the time of restarting, but may be started at all times.

The support layer 66 separates the filter medium from the starting water supply pipe 62 and the air supply pipe 63, and uniformly distributes the water and air to the filter medium layer at startup. Things. The support layer 66 may be, for example, a gravel-filled layer or the like, but is formed of a layer in which at least two or more types of granular materials are separately filled, similarly to the support layer of the first embodiment described above. Is the best.

Further, the support layer 66 is provided with a net capable of supporting the filter medium between the filter medium and the starting water supply pipe 62 and the air supply pipe 63 so as to separate the filter medium from the starting water supply means. The space around 65 and the air supply pipe 63 may be filled with water.

Since the starting water supply pipe 62 and the air supply pipe 63 are not used in a normal state, the support layer 66 formed of gravel or a net hardly clogs.

FIG. 13 is a perspective view showing only the lower portion of the water supply device 65.

The treated water supply means 65 is a cylindrical pipe on the upstream side, but its cross-sectional area gradually expands in the shape of a pyramid near the outlet. 65a is provided.

The size of the outlet should preferably be half or more than the cross-sectional dimension of the filtration tank 61, but if the area of the outlet is larger than the area on the upstream side, the effect of the present invention can be obtained. Is obtained. Since the openings 65a serve as outlets of the water to be treated, the openings 65a should be as wide as possible in the cross section of the filtration tank 61, and should preferably be widespread, but the number and intervals are not particularly limited.

Although the outlet has a square cross section, the cross section may be, for example, a circle depending on the cross sectional shape of the filtration tank 61, and the shape is not particularly limited. In addition, the cross-sectional area gradually increases in a pyramid shape from the cylindrical pipe on the upstream side to the outlet, because the filter medium is deposited on the upper surface of the outlet of the water supply pipe to be treated by inclining, and the filter medium is This is to prevent the formation of accumulated dead water areas.

It is preferable to use an upstream cylindrical pipe having a large diameter so as not to cause a bridge when the filter medium flows backward and is clogged in the pipe.

FIG. 14 is a perspective view of the lower part of the treated water supply means 65 as viewed from below. As shown here, the bottom surface of the treated water supply means 65 is open. With such a configuration, even if foreign matter is mixed into the water to be treated, the large area of the bottom surface is opened to the filter medium layer 67, so that the foreign matter does not clog the water supply means 65 to be treated. Further, in FIG. 14, the bottom surface is entirely open, but a portion may be shielded to the extent that foreign matter is not jammed.

FIG. 15 schematically shows a state in which water flows near the opening 65a.
The inside of 5 is filled only with water, whereas the outside of the treated water supply means 65 is a mixture of water and a filter medium. For this reason, as compared with the upper part of the opening 65a, the pressure at the lower part and the bottom of the opening 65a becomes higher due to the weight of the filter medium corresponding to the height of the opening 65a, and the bottom of the water to be treated is open. Nevertheless, it is discharged to the filter medium layer from the opening 65a.

For example, if the height of the opening 65a is 10 cm, and if the inside of the water-to-be-treated supply means 65 is filled only with water, the upper part of the opening 65a and the opening 65a
A pressure difference of 10 cmAq is generated at the lower and bottom surfaces due to the effect of the weight of the water due to the difference in water depth.

On the other hand, when the filter medium and the water flowing as in the outside of the water-to-be-treated supply means 65 are mixed, extra pressure is required to fluidize the filter medium. For example, if a filter medium having a specific gravity of 1.6 and a porosity of 0.6 is filled, 10 c
Due to the depth difference of m, there is a pressure difference of about 12.5 cmAq.

That is, since the pressure difference between the inside and the outside of the opening 65a becomes larger in the depth direction, the water to be treated is larger than the bottom and bottom of the opening 65a.
It is easier to flow from the top of a.

If the number or the area of the openings 65a is too small, the water flows from the bottom surface more than the openings 65a. In this case, the water easily flows from a part of the bottom surface and the water is supplied uniformly. Therefore, it is preferable that the resistance of water passing through the opening 65a be smaller than the pressure difference in the depth direction due to the weight of the filter medium.

In the present embodiment, the opening 65
Although a is a triangular notch, this is because the treated water supply means 65 is inclined with respect to the horizontal
Even when the substantial water depth of the opening 5a becomes shallower and the upper portion of the opening 65a becomes easier to flow, the opening 6
By reducing the size of 5a, the effect is reduced. Also, by increasing the outlet area toward the lower part, the supply amount of the water to be treated increases, and even if the water to be treated that passes through the notch increases, the effect can be reduced.

The shape of the opening 65a may be rectangular or the like in consideration of workability and the like, and the shape is not particularly limited.
If the height of the opening 65a is too small, a pressure difference due to the weight of the filter medium at the upper portion, the lower portion, and the bottom of the opening 65a hardly occurs.

In FIG. 15, the whole inside of the treated water supply means 65 is occupied only by water. However, by increasing the number and size of the openings 65a, as shown in FIG.
In some cases, water and the filter media are mixed in the lower part of the box.

FIG. 17 shows the second embodiment in which the number and shape of the water supply structures are changed.

In the filter device shown in FIG. 17, reference numeral 161 denotes a fluidized bed filter tank for passing and filtering water to be treated upward.
Reference numeral 2 denotes a starting water supply pipe, and reference numeral 162a denotes a starting water supply hole for blowing out the water to the filtration tank at the time of starting.
63 is an air supply pipe for supplying air for cleaning,
163a is a diffuser hole for blowing out cleaning air, and 165a.
Is a treated water supply means for supplying treated water to the filtration tank; 165a is an opening formed in a lower side surface of the treated water supply pipe; 165b is a check valve for preventing backflow of treated water;
c is a treated water supply pipe for supplying treated water, 166a is a drain pipe for draining water from the filtration tank 161, 167 is a filter medium layer filled with filter medium, 168 is an upper water collecting device, 169
Reference numeral 170 denotes a baffle plate for preventing the cleaning air from entering the water supply pipe 165c, and reference numeral 170 denotes an air supply unit for sending the cleaning air.

In this filtration apparatus, normally, the water to be treated is supplied from the treated water supply pipe 165c and passes through the treated water supply means 165, from the lower part of the filter medium layer 167 to the filter medium layer 1
67. The filter medium layer 167 is in a fluid state due to the flow of the water to be treated, and the water to be treated is purified by the contact between the filter medium of the filter medium layer 167 and the water to be treated, and is discharged as treated water from the upper water collecting device 168, or It is sent to the next process.

FIG. 18 is a perspective view showing the treated water supply means 165. The purpose of the opening 165a and the inclination is the same as that of the embodiment shown in FIG. 12, but as shown in FIG. 17 and FIG. Accordingly, a plurality of to-be-processed water supply means 165 may be arranged in the filtration tank 161.
Further, as shown in FIGS. 17 and 18, the water to be treated may be supplied to the treated water supply means 165 from the wall surface of the filtration tank 161.

FIG. 19 shows a second embodiment in which the shape and arrangement of the water supply structure are changed, and a rectifying plate is added. In the filtration device shown in FIG.
Is a fluidized bed filtration tank for passing and filtering the water to be treated upward.
66 is a starting water supply pipe for starting, 263 is an air supply pipe for supplying air for cleaning, 263a is a diffusing hole for blowing out air for cleaning, and 265 supplies water to be filtered to the filtration tank. 265a is a check valve for preventing backflow of the water to be treated, and 265c is a supply valve of the water to supply the water to be treated. The pipe 266a is a drain pipe for draining water from the filtration tank 161; 267 is a filter medium layer filled with a filter medium; 268 is an upper water collecting device; 270 is an air supply means for sending cleaning air; Water supply means 265
Air vent valve to remove air that has entered the interior of the
272 is a beam for fixing the water-to-be-treated supply means 265 so as not to move upward, 273 is a flange joint provided in consideration of assembly of the water-to-be-treated supply means, and 274 is an inside of the water-to-be-treated supply means. The lids 275a, 275b, and 275c provided for cleaning the rectifying plate for making the upward flow of the water to be treated supplied from the water supply means to the filter medium layer more uniform, and 276 is the rectifying plate A pedestal for supporting the water supply means in the filter medium layer, 277 is a current plate 2
A spacer 279 for providing a gap between 75a, 275b, and 275c is a flexible tube for absorbing the influence of a shift in the relative position between the water supply means 265 and the water supply pipe 265c, and 281 is a filter medium. Support layer for supporting, 2
Reference numeral 80 denotes a rectification unit for uniformly supplying the treated water supplied from the activated treated water supply means 266 or the air supplied from the cleaning air supply pipe 263 to the support layer and the filter medium layer at the time of startup. It is the lower space.

In this filtration apparatus, the water to be treated is normally supplied from the water supply pipe 265c, passes through the water supply means 265, and is passed through the lower part of the filter medium layer 267 to the filter medium layer 2.
67. The filter medium layer 267 is in a fluidized state due to the passage of the water to be treated, and the water to be treated is purified by the contact between the filter medium of the filter medium layer 267 and the water to be treated, and is discharged as treated water from the upper water collecting device 268, or It is sent to the next process.

FIG. 20 shows the water supply means 165, the pedestal 2
76, the current plate 275a, 275b, 275c is shown in a perspective view by being separated. As shown in FIG. 20, the to-be-processed water supply means is installed so as to be seated inside the base 276. Further, the to-be-processed water supply means 265 merely sits on the pedestal 276 and is not particularly coupled.

Further, the pedestal 276 is provided with
65 has a structure which spreads upward so as to be seated at an appropriate position. In FIG. 20, the base 276 is the support layer 27.
6 is fixed to the rectifying section 280 through the inside of the filter 6, but may be fixed to the wall surface of the filtration tank in consideration of workability and the like.
The current plates 275a, 275b, and 275c are formed by laminating perforated plates, and each has an appropriate gap by the spacer 277 shown in FIG.

As described above, the current plates 275a, 275
b, 275c are the filter medium layer 2 from the treated water supply means 265.
The hole provided in the perforated plate is provided in order to make the water to be treated supplied to 67 more evenly upward, but in consideration of clogging and the like, the opening provided in the water to be treated is provided. A hole having a large size is desirable. Further, in the present embodiment, a plurality of perforated plates are laminated, but one may be used. In the case of stacking a plurality of holes, it is preferable that the arrangement of the holes is shifted from each other.

The current plates 275a, 275b, 275
c are connected to each other via a spacer 277, but the current plates 275a, 275b, and 275c are connected to the pedestal 27.
It is not fixed especially just sitting on the upper part of 6. With such a configuration, the treated water supply means 26
5 and the flow straightening plates 275a, 275b, 275c can be easily removed because they are not fixed to the filtration tank. The means are described below.

Due to an unexpected situation, the treated water supply means 26
5 or the flow straightening plates 275a, 275b, 275c are clogged with a large foreign substance or the like, the normal operation is stopped, the water to be treated is supplied from the treated water supply means 266 for starting, and the filter medium 267 is in a fluid state. When the filter medium 267 is in a fluidized state, the water to be treated supply means 265 and the flow straightening plates 275a, 275b, 2 which are not fixed to the filtration tank.
75c can be easily pulled out from the upper part of the filtration tank.

After the repair, the treated water supply means 265 and the flow straightening plates 275a, 275b, 275c may be submerged again in the flowing filter medium layer. At this time, since the pedestal 276 extends upward, the treated water supply means 265 can be seated at an appropriate position even if the inside is not visible.

FIG. 21 is a perspective view showing the lower portion of the treated water supply means 265. As shown in FIG.
Although the opening 265a is a hole, there is an advantage that foreign matter is less likely to be clogged as compared with the cutout opening in the embodiment shown in FIG.

FIG. 22 shows a structure in which a collision plate 278 is attached to the outlet of the water supply means shown in FIG. By attaching the collision plate to the opening outlet, the water to be treated discharged from the opening 265a is dispersed right and left and flows to the outlet of the adjacent opening.
Is less likely to occur due to the blockage of part of the flow. Whether to provide the collision plate 278 may be determined in consideration of cost and the like.

The following shows the results of experiments relating to the present embodiment. The experiment was performed using a small filtration tank. The specifications are shown below.

Filtration tank specifications 500 mm square on one side, 1500 mm height Filtration speed 2 mm / s Filter material Cristobalite (specific gravity 1.6) Average particle size 0.35 mm Water to be treated Supply means Square shape as shown in FIG. 250mm opening 5mm diameter hole, 48 holes (12 holes per side)
Gravel support layer (for comparison) Uppermost layer Particle size 2 to 5 mm Middle layer Particle size 5 to 10 mm Lowermost layer Three layers with a particle size of 10 to 20 mm are packed in layers in a height of 70 mm each.

Using the above-mentioned experimental filtration tank, the uniformity of the flow and the rise in pressure loss due to the contaminated water flow were measured. As a comparative object, the flow uniformity was compared between the case of direct water supply by piping and the present embodiment, and the increase in pressure loss was compared between the case of the gravel support layer and the present embodiment. The pressure loss is the pressure difference between the inlet of the water to be treated and the outlet of the treated water.

First, the experimental results of the flow uniformity will be described. As an evaluation experiment, the tracer substance was injected into the raw water in a pulsed manner during the water flow operation, and the tracer substance was measured at the outlet. The flow is not uniform, short circuit in the filter media layer,
When water is flowing, the tracer substance will be detected at the outlet earlier than when flowing through the entire filter media layer. In addition, a small amount of sodium chloride was used as a tracer substance.

FIG. 23 shows the relationship between the concentration of the tracer substance measured at the outlet and the elapsed time after the injection of the tracer substance. It can be seen that, in the present embodiment, the time until the tracer substance is detected at the outlet is longer than the water supply with a single pipe.

FIG. 24 shows the results of each experiment.
The average time (average residence time) until a tracer substance is detected is converted and compared per 1 m of the filter medium. This clearly shows that the present embodiment has a longer average residence time, and therefore has less short-circuit flow and more uniform flow.

FIG. 26 shows the measurement of the increase in pressure loss due to the passage of contaminated water using artificial turbid water.
The vertical axis of the graph is the pressure loss due to water passage, and the horizontal axis is the elapsed time of water passage. The dotted line shows the result of a water flow experiment in a filtration tank using a gravel support layer, and the solid line shows the result of the present embodiment.

Thus, in the ordinary gravel support layer, as the elapsed time of water passage becomes longer, the pressure loss increases due to clogging. However, water is supplied using the treated water supply means in the present embodiment. It can be seen that the pressure loss hardly increases when the pressure drop occurs.

The effects obtained by adopting the second embodiment of the present invention will be described below.

During normal water flow, the water to be treated is directly supplied to the filter medium layer through the water to be treated supply means without passing through the support layer, so that the rise in pressure loss is greatly reduced and the necessity of washing the support layer is eliminated. Is almost gone. Further, since the water to be treated is supplied from a large number of openings provided in the water supply means, the filter medium flows evenly.

Further, since the bottom surface of the treated water supply means is open to the filter medium layer, even if a suspended matter larger than the size of the opening flows into the filtration tank together with the treated water, the treated water supply means is not affected. The supply means is not clogged. In addition, the filter medium does not fall or flow back below the support layer.

Further, by providing the pedestal, the water to be treated can be taken out without removing the filter medium, and maintenance can be performed very easily.

Further, by providing a flow straightening plate above the treated water supply means, the treated water supplied to the filter medium layer from the treated water supply means can flow more uniformly upward.

[0139]

According to the present invention, the frequency of cleaning for clogging can be greatly reduced, and the water to be treated can be stably applied to the filter medium layer.
Since uniform supply can be performed and the filter material can be prevented from falling,
The filtration performance can be improved, and the quality of the filtration device can be maintained for a long period of time.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a first embodiment of a filtration device according to the present invention.

FIG. 2 is a perspective view of a support section 6 of the filtration device of FIG.

FIG. 3 is a perspective view of a flow straightening unit 5 of the filtration device of FIG.

FIG. 4 is a perspective view of an air supply pipe 3 of the filtration device of FIG.

FIG. 5 is an enlarged perspective view of a support layer 6a and a protrusion 6b of FIG.

FIG. 6 is a view showing another example of the support unit of FIG. 2;

FIG. 7 is a diagram illustrating another example of the rectifying unit in FIG. 3;

FIG. 8 is a view showing another example of the air supply pipe of FIG. 4;

FIG. 9 is a perspective view of another support unit in which the support unit and the rectifying unit in the filtration device of FIG. 1 are integrated.

FIG. 10 is a view showing another example of the air supply pipe combined with the support unit of FIG. 9;

FIG. 11 is an enlarged perspective view of the support rectification device of the support unit of FIG. 9;

FIG. 12 is a schematic configuration diagram showing a second embodiment of the filtration device according to the present invention.

FIG. 13 is a perspective view of the treated water supply means of FIG.

FIG. 14 is a perspective view of the water-to-be-treated supplying means of FIG. 13 as viewed from another angle.

FIG. 15 is a schematic diagram of the vicinity of an outlet of the treated water supply means of the filtration device of FIG. 12, showing a state in which the entire inside of the treated water supply means is occupied only by water.

FIG. 16 is a schematic view of the vicinity of an outlet of the water-to-be-treated supply means of the filtration device of FIG. 12, showing that a lower portion of an opening is in a state where water and a filter medium are mixed.

FIG. 17 is a diagram showing an example in which the number and the shape of the to-be-treated water supply means of the filtration device in FIG. 12 are changed.

18 is a perspective view of the treated water supply means of FIG.

FIG. 19 is a view showing an example in which the shape of the treated water supply means of the filtration device in FIG. 12 is changed, and a pedestal and a flow straightening plate are added.

20 is a perspective view showing a water supply unit, a pedestal, and a flow straightening plate of the filtration device of FIG. 19;

FIG. 21 is a perspective view showing an example of a treated water supply unit of the filtration device of FIG.

FIG. 22 is a perspective view showing another example of the to-be-treated water supply means of the filtration device of FIG. 19;

FIG. 23 is a graph showing the relationship between the concentration of a tracer substance and the elapsed time after injection of the tracer substance in the experimental results in the second embodiment.

FIG. 24 is a graph showing comparison of average time (average residence time) until a tracer substance is detected in the experimental results in the second embodiment.

FIG. 25 is a graph showing a relationship between a water passage speed and a pressure loss and a relationship between a water passage speed and an expansion coefficient, based on experimental results in the first embodiment.

FIG. 26 is a graph showing the relationship between the passage time of polluted water and the pressure loss as experimental results in the second embodiment.

[Explanation of symbols]

1,61,161,261 ... filtration tank, 2,65c, 165
c, 265c: treated water supply pipe, 3, 33, 53, 63, 1
63, 263: Cleaning air supply pipe, 4, 54, 254 ...
Lower space, 5, 35, 280 rectifier, 5a, 35a rectifier, 5b, 35b shielded area, 6, 36, 56 support, 6a, 36a, 66, 166, 281 support layer, 6b,
36b: relaxation portion, 7,67,167, 267: filter medium layer,
8, 68, 168, 268: Upper catchment section, 10, 70, 17
0, 270: air supply means, 57: deceleration section, 58: cylindrical flow path, 59: net, 65, 165, 265: treated water supply means, 65a, 165a, 265a: opening, 102
... Rectification support device, 103 ... Casing, 105 ... Fixed part, 111 ... Particles a, 112 ... Particles b, 113 ... Particles c, 271 ... Air release valve, 272 ... Beams, 273 ...
Flange joint, 274 ... Flange lid, 275a, 27
5b, 275c: straightening plate, 276: base, 277: spacer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Fumitaka Handa 603, Kunitachi-cho, Tsuchiura-shi, Ibaraki Pref. Inside the Tsuchiura Plant of Hitachi Co., Ltd. Tsuchiura factory

Claims (7)

[Claims] 1. A filter tank filled with a filter medium and a support portion disposed below the filter medium layer and supporting the filter medium layer, and a filtration tank through which water to be treated is upwardly filtered. A filtration device having a treated water supply unit for supplying treated water from the lower part of the filtration tank through the support unit to the filter medium layer, wherein the support unit is filled with at least two or more types of granular materials for each type A filter device comprising: a support layer formed of a layer formed in such a manner that the shape of the granular material in each layer of the support layer is closer to a sphere as the upper layer and closer to a flat shape as the lower layer. 2. The filter according to claim 1, wherein each granular material of the support layer flows in a range from a substantially uppermost layer to a lowermost layer of the support layer. 3. A filter medium filled with a filter medium, and a support portion for supporting the filter medium layer, wherein water to be treated is supplied upward from a lower portion of a filtration tank provided therein, and the filter medium layer is passed through the support section. In the filtration device for filtering the water to be treated, the support section disperses the supplied water to be treated, passes the water to the filter medium layer, and supports the filter medium layer so that the filter medium layer does not drop down. A support layer formed of more than one type of granular material, and a relaxation portion that shields a part of the supplied water to be treated and alleviates a fluctuation in the flow rate of the water to be treated when passing through the support layer. A filtration device comprising: 4. A filtration device having a filter medium layer filled with a filter medium and a treated water supply means for supplying treated water to the filter medium layer, and having a filtration tank for passing the treated water upward and filtering. In the above-mentioned treated water supply means, the treated water supply means is arranged in a lower layer in the filter medium layer and supplies the treated water sent from a treated water supply pipe to a lower layer in the filter medium layer, and the treated water supply means An opening through which the water to be treated passes is provided on a side surface surrounding a bottom surface that is opened to be larger than a cross section of the water to be treated toward the bottom of the filtration tank. Filtration device. 5. A filtration apparatus having a filter medium layer filled with a filter medium and a treated water supply means for supplying treated water to the filter medium layer, and having a filtration tank for passing the treated water upward and filtering. In the above-mentioned treated water supply means, the treated water supply means is arranged in a lower layer in the filter medium layer and supplies the treated water sent from a treated water supply pipe to a lower layer in the filter medium layer, and the treated water supply means An opening through which the water to be treated passes is provided on a side surface surrounding a bottom surface that is opened to be larger than a cross section of the water to be treated toward the bottom of the filtration tank. A filtering device, characterized in that a pedestal is provided at a lower portion of the filtration tank for the water supply means to hold its position in the filter medium layer and guide it to a predetermined position. 6. A filter device having a filter medium layer filled with a filter medium and a treated water supply means for supplying treated water to the filter medium layer, and a filter tank for filtering the treated water upward through water. In the above-mentioned treated water supply means, the treated water supply means is arranged in a lower layer in the filter medium layer and supplies the treated water sent from a treated water supply pipe to a lower layer in the filter medium layer, and the treated water supply means An opening through which the water to be treated passes is provided on a side surface surrounding a bottom surface that is opened to be larger than a cross section of the water to be treated toward the bottom of the filtration tank. A filtering device, wherein a flow straightening plate is provided above the water supply means to make the upward flow of the water to be treated uniform. 7. A filter medium layer filled with a filter medium, a support layer for supporting the filter medium layer, and a treated water supply means for supplying treated water to the filter medium layer are provided inside, and the treated water is passed upward. In a filtration device having a filtration tank for performing water filtration, the support layer is formed of a layer in which at least two or more types of particulate matter are individually filled, and the water-to-be-treated supply means is a lower layer in the filter medium layer. The to-be-treated water sent from the to-be-treated water supply pipe is supplied to a lower layer in the filter medium layer, and toward the bottom of the filtration tank of the to-be-treated water supply means, the to-be-treated water supply pipe is A filtering device, characterized in that an opening through which the water to be treated passes is provided on a side surface surrounding a bottom surface that is opened to be larger than a cross section.