JP2001162110A - Laminated filter and filtering device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized laminated filter regenerable by removing suspended matter accumulated on the filter, excellent in filtration characteristics and mechanical characteristics and manufacturable at a low cost, and also provide a filtering device using the laminated filter. SOLUTION: This laminated filter 1 is obtained by laminating plural ring- shaped filtering bodies 2 and has an inflow part of the liquid to be treated on one side of the inner peripheral laminated surface and the outer peripheral laminated surface and an outflow part of the treated liquid on the other side. Plural penetrated holes having the pore size larger than those of the suspended solids are formed on each of the bodies 2 to direct the hole axes to the thickness direction and notches are formed on the inner peripheral edge and the outer peripheral edge of the bodies 2 respectively. Filtration passages are formed between the notch of the inner peripheral edge and that of the outer peripheral edge by communicating between the adjacent bodies 2 by superposing the penetrated holes on one another.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated filter formed by laminating a plurality of flat filter bodies and a filtering device using the same.

[0002]

2. Description of the Related Art A filtration device for removing suspended matter in a liquid to be treated such as sewage or wastewater uses a filtration material having mesh-like pores formed by a hollow fiber membrane or the like. Are known.

For example, Japanese Patent Application Laid-Open No. Hei 10-52608 (hereinafter referred to as "A") discloses a method in which a large number of porous filter media having a large number of fine pores are brought into close contact with each other, and the contact surfaces thereof are separably laminated. In addition, a method is disclosed in which a liquid to be treated is passed through and filtered through each of the porous filtration materials in the tight contact state.

[0004]

However, the prior art disclosed in the above-mentioned publication has the following problems.

[0005] (1) The porous filter medium captures the suspension in a state of being compressed by a water flow at a portion of mesh-like pores or depressions smaller than the suspension. There is a problem that the liquid is accumulated in the portion and clogging easily occurs.

(2) If the porous filter medium is once clogged, it is difficult to remove the suspended matter from the pores and depressions. The only option is to dissolve using chemicals or replace the filter media.

(3) In order to reduce the size of the filtration material, it is necessary to increase the filtration area and the number of filtration passages per passage area through which the liquid to be treated flows. It is effective to stack many filter bodies within the same height. However, when the thickness of the porous filter material is reduced, there is a problem that the strength is reduced and the filter material becomes brittle.

(4) The porous filter medium has a problem that it is difficult to control and control the pore diameter of the pores or depressions, the production method is complicated, and the production cost is high.

The present invention has been made to solve the above-mentioned conventional problems, and it is possible to remove and regenerate the suspended matter accumulated in a filter, to have excellent filtration characteristics and mechanical characteristics, to be manufactured at a low cost and in a small size. It is an object of the present invention to provide a laminated filter that can be used and a filtering device using the same.

[0010]

According to the laminated filter of the present invention, a plurality of through-holes having a pore diameter larger than the particle diameter of the suspension are formed in each of the filter bodies with the pore axis directed in the thickness direction. Notches are formed at the inner peripheral end and the outer peripheral end of the filter body, respectively, and between the notch at the inner peripheral end and the notch at the outer peripheral end, a through hole between the filter bodies is formed. The filter passage is formed so as to be communicated by the overlap.

As a result, it is possible to provide a laminated filter that can be regenerated by removing suspended matter accumulated in the filter, has excellent filtration characteristics and mechanical characteristics, can be manufactured at low cost, and can be manufactured in a small size.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the laminated filter according to the first aspect of the present invention, a plurality of ring-shaped filter bodies are laminated, and an inflow portion of a liquid to be treated is provided on one of an inner peripheral laminated surface and an outer peripheral laminated surface. A laminated filter provided with an outflow portion of a liquid to be treated on the other side, wherein a plurality of through-holes having a pore diameter larger than the particle diameter of the suspension are formed in each of the filter bodies with the pore axis directed in the thickness direction. At the same time, a notch is formed at each of an inner peripheral end and an outer peripheral end of the filter body, and between the notch at the inner peripheral end and the notch at the outer peripheral end, the gap between the filter bodies is formed. Are formed so as to communicate with each other by overlapping of the through holes.

As a result, the following effects can be obtained.

(A) The cross-sectional area of the flow passage of the filtration passage can be set to various sizes depending on the degree of overlap between the openings of the through-holes. By adjusting the ratio and the flow path resistance to the flow of the liquid to be treated, the suspension can be efficiently filtered.

(B) When the liquid to be treated is in a filtration treatment state in which the liquid is passed through the filtration passage, the suspended matter in the liquid to be treated is passed through the filtration hole and / or the through hole formed by the overlap between the through holes. It can be captured by drawing it into a swirl or a stagnation area.

(C) At the time of performing the regeneration treatment of the laminated filter in which the suspended matter is captured, the suspended matter has no binding force by providing at least a gap between the laminated layers of the filter bodies larger than the suspended matter. State. By flowing the washing liquid in this state, the suspension can be easily discharged out of the filter.

(D) The filter is made of aluminum, copper, iron,
A non-permeable material made of metal such as stainless steel, ceramic such as alumina, zirconia, silica, or plastic such as polyethylene, polypropylene, polyvinyl chloride, etc. was used as a material, and a large number of through holes were formed in the material by drilling or the like. For example, when metal such as aluminum or ceramic such as alumina is used, the thickness of the filter can be reduced while maintaining the required strength of the filter. When using an impermeable material such as plastic,
Processing is easy.

(E) The through hole has a diameter of, for example, 0.1 m.
m or more, it can be manufactured by punching, die molding and the like, and the hole diameter can be easily controlled.

(F) Since the supply holes and the cutouts on the discharge side are formed in the through holes at both ends of the filter, the liquid to be treated is supplied from a direction perpendicular to the lamination direction of the filter. Then, the liquid to be treated, which has been processed through the filtration passage, can be discharged from the opposite side, and the suspension in the liquid to be treated can be removed most efficiently in accordance with the particle diameter, flow rate, etc. The turbid matter can be filtered.

Here, the ring-shaped filter is a plate-like body having an opening at the center, for example, a donut-shaped one having a circular inner and outer periphery, a triangular or other polygonal inner and outer periphery, and the like. Things included.

The inner peripheral laminated surface and the outer peripheral laminated surface refer to the inner wall surface and the outer wall surface of the laminated ring-shaped filter. Also,
The inner peripheral end and the outer peripheral end mean the inner and outer peripheral edges of the ring-shaped filter. The hole axis of the through hole is a so-called center line connecting the center points of the cross sections of the through hole.

The laminated filter is formed by, for example, laminating 10 to 100 filter bodies in a separable state without using an adhesive or the like.

The pore size larger than the particle size of the suspension means the largest average particle size (representative) when the particle size distribution of the substance to be filtered most in the liquid to be treated (assumed removal substance) is taken. Value) on the large particle size side,
The particle diameter of particles including 40% of the total number on the large particle diameter side (50% when viewed as a whole) (90% is included in the total number of the particles, that is, the relative cumulative frequency) (Referred to as particle size).

For example, if the liquid to be filtered is bath water used in a bathtub, and it is desired to filter turbid substances in the bath water,
Assumed removal substances are oils and fats, sebum cells, etc. (normally,
The size is 5 to 60 μm), and bacteria having different properties (usually 0.3 to 3 μm in size) and large hair are excluded. In the case where the assumed removal substance is a turbid substance, a hole larger than 90% particle diameter of the turbid substance is formed in the filter, whereby a turbid substance or a suspension such as hair larger than the turbid substance is filtered. . In the multilayer filter of the present invention, the degree of distribution of the overlapping openings (filtration holes) changes depending on the number and distribution of through holes formed in the filter, and the filtration performance is slightly affected by the properties of the liquid to be treated. Therefore, when the distribution of the assumed removal substance is abnormally widened to the smaller diameter side, it is effective in some cases to reduce the pore diameter to a particle diameter near the representative value.

What should be the diameter of this hole,
Explaining with a specific example, when the liquid to be treated is bath water, the 90% particle size is 30 to 50 μm. As described above, the assumed removal substances are turbid substances in the bath water, and do not filter bacteria. Assuming that a sufficient number of the through holes are evenly distributed, the diameter of the through hole of the filter is preferably about 300 to 700 μm, which is one order larger than the 90% particle size.

When the liquid to be treated is tap water, the 90% particle size is 5 to 10 μm.
１００100 μm is preferred. Further, in the case where the liquid to be treated is tap water stored and hypochlorous acid is removed, the supposedly removed substance becomes a bacterium, and the 90% particle size becomes 3 μm. At this time, the diameter of the through-hole of the filter is preferably 20 to 50 μm.

[0027] A laminated filter according to a second aspect is configured such that the laminated filter is sandwiched between non-permeable supporting plates in the first aspect.

As a result, the following operation can be obtained in addition to the operation of the first aspect. (A) Since the filter body to be laminated is supported on the upper and lower sides by the non-permeable support plate, an inflow portion or an outflow portion can be formed, and a short path of the liquid to be treated near the upper or lower surface thereof can be formed. In addition to preventing the filtered liquid from leaking to the upper or lower surface.

(B) Even if the laminated filter is placed horizontally,
The filter can be maintained in a laminated state while maintaining the predetermined strength.

(C) By providing a support mechanism capable of freely setting the distance between the non-water-permeable support plates and holding the stacked filter bodies, the flow characteristics of the filtration channel formed in the filter can be improved. By changing it, the accumulated suspension can be efficiently washed and removed, and the particle size and the like of the suspension to be filtered can be selected. Here, the support mechanism for setting the interval between the non-water-permeable support plates can be configured by a screw mechanism or the like that connects the upper and lower non-water-permeable support plates.

[0031] The laminated filter according to claim 3 is configured such that in claim 1 or 2, the through-hole of the filter has a straight shape.

Thus, in addition to the function of the first aspect, the following function can be obtained. (A) Since there is no branch portion in the through hole, the flow of the liquid to be treated in the filtration passage can be made smooth, the flow resistance can be reduced, and the treatment efficiency can be improved.

(B) Since the through holes can be formed easily and precisely by a method such as punching, a laminated filter having excellent filtration efficiency can be manufactured at low cost.

The straight shape means that the through-hole is formed with the hole axis directed in the thickness direction of the filter, and does not have a structure in which the through-hole branches inside.

Here, the through hole having a branch is a hole having one opening on one surface side of the filter and having two or more openings on the other surface side. Those having a small branch that does not communicate with the outside of the filter are included in the straight shape.

According to a fourth aspect of the present invention, there is provided the laminated filter according to any one of the first to third aspects, wherein the cross section of the through hole of the filter is the same.

Thus, the following operation can be obtained in addition to the operation of any one of the first to fourth aspects. (A) Since there is no change in the cross-sectional area of the flow path in the through-hole, the flow of the liquid to be processed flowing through the through-hole can be made smooth and uniform.

(B) Since the through-holes have the same shape with respect to the thickness, the laminated filter can be manufactured more easily and at low cost by punching and die processing.

According to a fifth aspect of the present invention, in the laminated filter according to any one of the first to fourth aspects, a depression is formed in a periphery of an opening of the through hole.
5. The laminated filter according to any one of items 4 to 4.

Thus, in addition to the function of any one of claims 1 to 4, the following function is obtained. (A) Since there is a depression in the peripheral edge of the opening of the through hole in the thickness direction, the flow path cross-sectional area at that portion can be partially enlarged, and the water flow resistance when the liquid to be treated flows can be reduced.

(B) By forming a recess between adjacent through holes to connect the through holes, the flow of the liquid to be treated is changed in a complicated manner, whereby the suspended matter can be effectively captured.

According to a sixth aspect of the present invention, there is provided a filtration device using the laminated filter according to any one of the first to fifth aspects.

Thus, the following operation is provided.

(A) Since a laminated filter in which the pore size of the filter can be easily controlled can be used, it is possible to provide a device having little variation in the filtration process and high regeneration efficiency.

(B) Since the laminated filter can be designed to be small in the laminating direction (thickness direction), the device can be made compact and the filtration device can be operated with a small installation area.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1) FIG. 1 is a perspective view of a laminated filter applied to a filtration device according to Embodiment 1 of the present invention, and FIG. 2 is a part of FIG. 1 showing a flow of a liquid to be treated inside a laminated body. It is an enlarged view.

In FIG. 1, 1 is the laminated filter of the first embodiment, 2 is a filter formed in a ring shape, 3 is a large number of through-holes formed in the filter 2, and 4 is a filter having 10 to 10 filters.
A 50-layer laminated body having a cylindrical ring shape as a whole, 5 is a supply-side notch cut out in an outer peripheral edge of the filter body 2 in an arc shape, and 6 is an arc-shaped notch in the inner peripheral edge of the filter body 2. A notch on the discharge side, a disc-shaped upper surface holding plate 7 as a non-permeable support plate for fixing the upper portion of the laminate 4, 8
Reference numeral 9 denotes a disc-shaped lower surface pressing plate which is a water-impermeable support plate for fixedly supporting the lower portion of the laminate 4. Reference numeral 9 denotes a discharge pipe attached to the lower surface pressing plate 8 for discharging the liquid to be processed after the processing. is there.

The laminate 4 has a discharge side notch 6 on the inner peripheral laminate surface.
Are formed so as to be exposed, and the supply-side cutouts 5 are exposed on the outer peripheral laminated surface. An outflow portion that covers the inner peripheral laminated surface of the laminate 4 and can collect the liquid to be treated after filtration, and an inflow portion that covers the outer peripheral laminated surface and can supply the liquid to be treated, Provided for.
In the first embodiment, the space surrounded by the upper surface holding plate 7, the lower surface holding plate 8, and the inner peripheral lamination surface of the laminate 4 constitutes an outflow portion together with the discharge pipe 9 connected thereto. Although not shown in FIG. 1, the inflow portion may be any type of cover that covers the outer peripheral laminated surface. As described above, in the multilayer filter 1 of the first embodiment, the liquid to be treated flows in from the inflow portion on the outer periphery of the multilayer body 4 and is discharged from the outflow portion in the interior. However, the flow direction of the liquid to be treated can be reversed so that the inflow portion is provided inside the laminate 4 and discharged from the outflow portion provided outside. At this time, the positions of the supply-side notch 5 and the discharge-side notch 6 are reversed, the supply-side notch 5 is formed at the inner peripheral end of the filter 2, and the discharge-side notch 6 is formed at the outer peripheral end of the filter 2. Part will be formed. In the laminated filter 1 in this case, many supply-side cutouts 5 are exposed on the inner peripheral laminated surface, and many discharge-side cutouts 6 are exposed on the outer peripheral laminated surface. Providing the inflow portion on the outer periphery can increase the filtration area at the time of inflow, and can slightly increase the time until regeneration. However, which of the inflow portions may be selected from the arrangement relationship of the piping and the like.

The filtration device is a device for treating a liquid to be treated such as sewage or waste water, and filtering and removing contained suspended matter by using a laminated filter 1. And the liquid to be treated is supplied using the difference in water level from the storage tank.

The filter 2 has a ring shape made of a plastic material such as polyethylene, polypropylene or polyurethane.

In the present embodiment, the inner and outer circumferences are of a donut shape having a circular shape, but instead, various shapes such as a triangle and a quadrangle can be used according to the application.

A large number of through-holes 3 having a diameter D are formed in the filter body 2 perpendicularly to the surface thereof. The distance L between the centers of the adjacent through-holes 3 is 1.2 to 1.8 of the diameter D of the through-hole. It is formed in the range of twice. The diameter D is set to be in a range of 0.4 to 1.0 times the thickness d of the filter 2.

A plurality of the filter bodies 2 are laminated with no gap in the thickness direction to form a laminate 4 having a cylindrical ring shape. The laminate 4 includes an upper surface holding plate 7 which is a non-permeable support plate.
And the lower surface holding plate 8. At this time, the uppermost filter body 2 of the laminated body 4 and the upper surface holding plate 7 are in close contact with each other without any gap. Similarly, the lowermost filter body 2 of the laminated body 4 and the lower surface holding plate 8 are in close contact with each other without any gap. Further, the lower holding plate 8 is provided with a discharge pipe 9 for guiding the liquid to be processed to the outside of the laminated filter 1 at an inner portion of the inner peripheral laminated surface of the filter not in contact with the lowermost filter 2. Have been.

The outflow portion of the present embodiment is formed by the internal space formed by the upper surface holding plate 7, the lower surface holding plate 8, and the inner peripheral lamination surface of the laminate 4, and the discharge pipe 9. Since the liquid to be treated flows in from the outer peripheral lamination surface of the laminate 4, an inflow chamber (inflow portion of the present invention) is provided so as to cover the periphery of the outer peripheral lamination surface, but this is not shown.

The distance A between the upper holding plate 7 and the lower holding plate 8 which sandwich the laminated body 4 can be freely adjusted by a screw mechanism (supporting mechanism) (not shown). Can be created. For example, the total thickness N of a laminate composed of N pieces of filter bodies 2 having a thickness d
By setting the interval A to A> N × d with respect to × d, a gap can be generated between the filter bodies 2.

The liquid to be treated is introduced from the outer peripheral side of the laminated body 4 in a direction perpendicular to the laminating direction, flows in from the supply side notch 5 provided on the outer peripheral laminated surface, and flows inside the laminated body 4. It is filtered through the filtration channel and flows out to the inner peripheral side. The filtered liquid is led out of the laminated filter 1 through the discharge pipe 9.

In the above-described configuration, the upper surface pressing plate 7 or both the upper surface pressing plate 7 and the lower surface pressing plate 8 may be connected to the discharge pipe 9 in a sealed state.

Further, the flow of the liquid to be treated is also introduced from the inflow portion on the inner peripheral laminated surface side of the cylindrical laminated body 4, passes through the filtration passage inside the laminated body 4, and flows out on the outer peripheral laminated surface side It may be configured so as to flow out to the section.

FIG. 2 is an enlarged view of the cross section of FIG. 1 and is a perspective view showing the flow of the liquid to be treated inside the laminate 4. The liquid to be treated is discharged while being squeezed by the overlap of the through holes 3 formed by laminating the filter bodies 2 from the supply side cutouts 5 at the outer (or inner) end of the filter bodies 2. It flows into the filtration passage communicating with the notch 6. The inflowing treated water flows into another opening (filtration hole) formed so as to further overlap with the through hole 3 of the stacked filter body 2. in this way,
Thereafter, the liquid finally passes through the filtration passage formed by the overlap of the openings of the through holes 3 and finally reaches the discharge side cutout 6 at the inner peripheral (or outer peripheral) end.

FIG. 3 is an enlarged cross-sectional view of FIG. 2 showing a mechanism of filtering a suspension, and shows a mechanism of filtering a suspension contained in a liquid to be treated.

When the liquid to be treated passes through the filtration passage formed by the overlap of the through holes 3, a suspension larger than the overlapping opening (filtration hole) between the adjacent through holes 3 can pass through this portion. Without being caught. The filtration holes have various diameters including fine holes depending on the degree of overlap between the through holes 3.

Due to the difference between the size of the formed filtration hole and the diameter of the through hole 3, the velocity distribution of the liquid flow inside the through hole 3 is not uniform. Thereby, a stagnation area and a vortex of the flow are generated inside the through-hole 3. Small suspensions are also trapped by being drawn into these pools.

The suspension is trapped in the through hole 3 of the filter body 2 by the above two mechanisms.

FIG. 4 is a perspective view showing a regeneration mechanism of the laminated filter.

As shown in FIG. 4, at the time of regeneration, the distance L between the upper holding plate 7 and the lower holding plate 8 is adjusted by using a support mechanism (not shown), so that at least A large gap h is provided. by this,
The suspended matter trapped in the through-hole 3 is in a free state without being restrained, and by flowing a washing liquid or the like in this state, the suspended matter is removed from the through-hole 3 into the gap between the filter bodies 2. And flows out of the laminate 4 easily.

FIG. 5 is a schematic diagram showing the flow of the liquid to be treated when the inlet and the outlet of the through hole are not one-to-one. When the cleaning liquid or the like enters the through hole 3 from above, the flow is disturbed at the branch portion, and the velocity distribution is not uniform. Thereby, a stagnation area and a vortex of the flow are generated inside the through-hole 3. If the suspension is taken into this, it is difficult to get out of the through-hole 3. Therefore, it is desirable that the inlet and the outlet correspond one-to-one and have a straight shape without branching.

The straight hole may be a hole having a taper. If the inlet and the outlet correspond one-to-one, there may be a branch having a branch passage that does not communicate with the outside.

FIG. 6 is a schematic diagram showing the flow of the liquid to be treated when the through holes are not identical in the thickness direction. When the liquid enters the through hole 3 from above, the velocity distribution becomes non-uniform due to the disturbance of the flow at the widening portion or the narrow portion. Thereby, a stagnation area and a vortex of the flow are generated inside the through-hole 3. If the suspension is taken into this, it is difficult to come out of the through-hole 3. Therefore, it is preferable that the through-hole 3 has the same cross-sectional shape in the hole axis direction.

The laminated filter 1 and the filtering device according to the first embodiment have the following functions because they are configured as described above.

(1) The cross-sectional area of the flow passage of the filtration passage can be set to various sizes depending on the degree of overlap between the openings of the through-holes. By adjusting the ratio and the flow path resistance to the flow of the liquid to be treated, the suspension can be efficiently filtered.

(2) When the liquid to be treated is in a filtration treatment state in which the liquid is passed through the filtration passage, the suspension in the liquid to be treated is passed through the filtration holes and / or the through holes formed by the overlap between the through holes. It can be trapped in the vortex and the stagnation area formed inside.

(3) At the time of performing the regeneration treatment of the laminated filter in which the suspended matter has been captured, the suspended matter has no binding force by providing at least a gap between the layers of the filter bodies larger than the suspended matter. State. By flowing the washing liquid in this state, the suspended matter can be easily discharged out of the filter.

(4) Since there is a support mechanism that can freely set the interval between the non-water-permeable support plates, the flow characteristics in the filtration flow path inside the laminate are changed, and the accumulated suspension is removed. Efficient washing and removal can be performed, and the particle size of the suspension to be filtered can be selected.

(Embodiment 2) FIG. 7 is a sectional view showing a flow of a liquid to be treated in a multilayer filter according to Embodiment 2 of the present invention.

In FIG. 7, reference numeral 10 denotes a through hole provided in the filter, and reference numeral 11 denotes a depression provided on the wall surface of the filtration passage other than the through hole 10.

Since the multilayer filter of the second embodiment is configured as described above, the following functions are provided.

When the filter 2 does not have a depression as in the first embodiment, the filtration passage is interrupted where there is no overlap between the through holes 3. However, as shown in FIG. 7, when the filter body 2 has the depression 11, the filtration passage is narrowed or cut off in the first embodiment, and the channel cross-sectional area is partially enlarged by the depression 11 in the place where the filtration passage should be interrupted. It is possible to form a filtration passage having a small water flow resistance. Therefore, the liquid to be treated can be supplied to the filtration device with low energy to perform the filtration treatment, and the operation can be performed economically and efficiently.

(Embodiment 3) FIG. 8 is a sectional view showing a flow of a liquid to be treated in a multilayer filter according to Embodiment 3 of the present invention.

In FIG. 8, reference numeral 20 denotes a through hole provided in the filter body, reference numeral 21 denotes a depression provided in the wall of the filtration passage other than the through hole 20, and reference numeral 22 denotes a hole formed in the direction along the stacking direction of the stack. It is a horizontal through hole connecting the holes 20.

Since the laminated filter of the third embodiment has the above configuration, it has the following operation.

In the case where the filter body 2 does not have a recess or a through hole other than in the thickness direction as in the first embodiment, the filtration passage is interrupted where the through holes 3 do not overlap with each other. However, as shown in FIG. 8, when the filter body is formed with the recess 21 or the horizontal through hole 22 other than the thickness direction, the flow path resistance of the liquid to be treated can be further reduced, and the liquid to be treated is passed through the filtration passage with low energy. Can be shed.

[0083]

As described above, according to the present invention, it is possible to provide a resource-saving type laminated filter which requires a small amount of energy for regeneration, has a high energy saving effect, and does not require replacement of the filter due to clogging. In addition, there is no restriction on the direction of filtration (flow of liquid) or the direction of mounting the filter, so that it is possible to achieve an excellent effect that the size can be reduced and the production is easy.

According to the laminated filter of the first aspect, the following effects can be obtained.

(A) The cross-sectional area of the flow passage of the filtration passage can be set to various sizes depending on the degree of overlap between the openings of the through-holes. By adjusting the ratio and the flow path resistance to the flow of the liquid to be treated, the suspension can be efficiently filtered.

(B) When the liquid to be treated is in a filtration treatment state in which the liquid to be treated is passed through the filtration passage, the suspension in the liquid to be treated is passed through the filtration holes and / or the through holes formed by the overlap between the through holes. It can be trapped by being drawn into the vortex or stagnation area formed inside.

(C) When performing the regeneration treatment of the laminated filter in which the suspended matter is captured, at least a gap between the laminated layers of the filter bodies is made larger than that of the suspended matter so that the suspended matter has no binding force. State. By flowing the washing liquid in this state, the suspension can be easily discharged out of the filter.

(D) It can be manufactured by punching, die molding or the like, and the hole diameter can be easily controlled.

According to the laminated filter of the second aspect, the following effects can be obtained in addition to the effects of the first aspect.

(A) Since the filter body to be laminated is supported on the upper and lower sides by a non-permeable support plate, the inflow portion or the outflow portion can be easily formed, and the liquid to be treated close to the upper surface or lower surface thereof can be formed. And has the effect of preventing the filtered liquid from escaping to the upper or lower surface.

(B) Even if the laminated filter is placed horizontally,
The filter can be maintained in a laminated state while maintaining the predetermined strength.

(C) By providing a support mechanism capable of freely setting the distance between the non-water-permeable support plates and sandwiching the stacked filter bodies, the flow characteristics of the filtration channel formed in the filter can be improved. By changing it, the accumulated suspension can be efficiently washed and removed, and the particle size and the like of the suspension to be filtered can be selected.

According to the laminated filter of the third aspect, the following effects can be obtained in addition to the effects of the first aspect. (A) Since there is no branch portion in the through hole, the flow of the liquid to be treated in the filtration passage can be made smooth, the flow resistance can be reduced, and the treatment efficiency can be improved.

(B) Since the through-holes can be formed easily and precisely by a method such as punching, a laminated filter having excellent filtration efficiency can be manufactured at low cost.

According to the laminated filter of the fourth aspect, the following effects can be obtained in addition to the effects of any one of the first to fourth aspects.

(A) Since there is no change in the cross-sectional area of the flow path in the through-hole, the flow of the liquid to be processed flowing through the through-hole can be made smooth and uniform.

(B) Since the through-holes have the same shape with respect to the thickness, the laminated filter can be manufactured more easily and at low cost by punching and die processing.

According to the laminated filter of the fifth aspect, the following effects can be obtained in addition to the effects of any one of the first to fourth aspects.

(A) Since there is a recess at the periphery of the opening of the through hole in the thickness direction, the flow path cross-sectional area at that portion can be partially enlarged to reduce the water flow resistance when the liquid to be treated flows. .

According to the filtering device using the laminated filter according to the sixth aspect, the following effects can be obtained.

(A) Since a laminated filter in which the pore size of the filter can be easily controlled can be used, it is possible to provide an apparatus having a small variation in the filtration process and a high regeneration efficiency.

(B) Since the laminated filter can be designed to be small in the laminating direction (thickness direction), the apparatus can be made compact and the filtration apparatus can be operated with a small installation area.

[Brief description of the drawings]

FIG. 1 is a perspective view of a multilayer filter applied to a filtration device according to Embodiment 1 of the present invention.

FIG. 2 is a partially enlarged view of FIG. 1 showing a flow of a liquid to be treated inside a laminate.

FIG. 3 is an enlarged cross-sectional view of FIG. 2 showing a mechanism by which a suspension is filtered;

FIG. 4 is a perspective view showing a regeneration mechanism of the multilayer filter.

FIG. 5 is a schematic diagram showing the flow of the liquid to be treated when the inlet and the outlet of the through hole are not one-to-one.

FIG. 6 is a schematic diagram showing the flow of a liquid to be treated when the through holes are not identical in the thickness direction.

FIG. 7 is a cross-sectional view illustrating a flow of a liquid to be treated in a multilayer filter according to Embodiment 2 of the present invention.

FIG. 8 is a cross-sectional view showing a flow of a liquid to be treated in a multilayer filter according to a third embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 laminated filter 2 filter body 3 through hole 4 laminated body 5 supply side cutout 6 discharge side cutout 7 upper surface holding plate 8 lower surface holding plate 9 discharge pipe 10 through hole 11 recess 20 through hole 21 recess 22 horizontal through hole

Claims (6)

[Claims] 1. A laminated filter in which a plurality of ring-shaped filters are laminated, and an inflow portion of the liquid to be treated is provided on one side of an inner peripheral laminating surface and an outer peripheral laminating surface, and an outflow portion of the liquid to be treated is provided on the other side. In each of the filter bodies, a plurality of through-holes having a pore diameter larger than the particle diameter of the suspension is formed with the pore axis oriented in the thickness direction, and the inner peripheral end portion and the outer peripheral end of the filter body A cutout is formed in each of the portions, and a filtration passage is formed between the cutout in the inner peripheral end and the cutout in the outer peripheral end so as to communicate with each other by overlapping the through holes between the filter bodies. A laminated filter, characterized in that: 2. The laminated filter according to claim 1, wherein the laminated filter is sandwiched between non-permeable support plates. 3. The laminated filter according to claim 1, wherein the through-hole of the filter is straight. 4. The multilayer filter according to claim 1, wherein the cross sections of the through holes of the filter are the same. 5. The multilayer filter according to claim 1, wherein a depression is formed in the periphery of the opening of the through hole. 6. A filtering device comprising the multilayer filter according to claim 1.