JP2012000577A - Filtering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filtering device which reduces the load given to a stirring member during a cleaning operation, and which can decrease the breakage of a filter medium caused by the collision with the stirring member.SOLUTION: The filtering device, provided with a stirring rod for stirring the filter medium which is fixed to a rotary shaft and to which contaminants adhere, includes a lower stirring rod installed in a position buried in the filter medium and an upper stirring rod installed in the position not buried in the filter medium, as the stirring rod fixed to the rotary shaft, and an agitation blade extending downward from the upper stirring rod so as to be at least partially to be buried in the filter medium.

Description

  The present invention relates to a filtration device that filters a liquid such as water, and more particularly to a filtration device that has a cleaning mechanism for a filtering material inside.

Conventionally, in hot spring facilities and swimming pools, a circulating water purification device is used to filter the water used in the water storage tank with a filtration device and inject sterilizing chemicals as necessary to circulate while sterilizing and purifying. Are being reused. In this specification, water / hot water that is circulated and reused while using a filtration device is referred to as “circulated water”.
As a general filtering device, for example, a filter having a structure in which a filter medium such as large-diameter gravel is laid in a filter tank and small-diameter filter mediums are sequentially stacked on the filter medium is known. This filtration device supplies the circulating water before filtration from above the filtration tank, and permeates the inside of the layered filter material downward, so that the pollutant contained in the circulating water adheres to the filter material of each layer, and clean circulating water is obtained. It is a mechanism to obtain.

Here, when the filter device is used for a long time, the filter medium may be clogged with contaminants, and the filtration efficiency may be reduced, resulting in deterioration of the quality of the circulating water. For this reason, it is necessary to remove the pollutant adhering to the filter medium and eliminate clogging.
It is desirable that the so-called cleaning operation for removing the pollutant from the filter medium can be performed in as short a time as possible without increasing man-hours and space in order to increase the operating efficiency of the facility.
For example, when the filtration device is used in a hot spring facility, it is preferable to perform the cleaning operation at the start or end of work every day, so that the filter medium can be stored in the filtration tank for a short time without being taken out of the filtration tank. In some cases, a filter medium cleaning mechanism is previously provided in the filter tank so that the filter can be efficiently cleaned.
Here, in the case of the method in which the filter media are layered in the filter tank as described above, so-called backwash cleaning is performed to remove the pollutant by flushing cleaning water upward from below the lowermost filter media as a cleaning operation. It is common to do it. However, in the process of filtration work, contaminants may adhere to the filter medium layer, and a water passage may be formed in the layer. In this case, the washing water is mainly used only for this water passage during backwashing. Therefore, there is a possibility that the filtering medium located at a position away from the water passage is not sufficiently washed, and a hotbed of bacteria such as Legionella bacteria may be formed.

In order to solve such a problem, for example, a filtration device as shown in FIG. 4 is known (Patent Document 1).
4 includes a container 1, a partition plate 2 that divides the inside of the container 1 into two upper and lower spaces, a filter medium 29 accommodated in the upper space 4, a shaft 14 that extends vertically in the container, Are provided with a plurality of stirring blades 15.
The filtering material is deposited on the partition plate in the container, and the circulating water is filtered by permeating downward between the filtering materials.
And the axis | shaft is rotated using the drive mechanisms 16-19, 24-26, etc. which were provided in the exterior of the container, and the agitation blade rotates in the container 1, thereby removing the contaminants adhering to the filter medium, The cleaning operation is performed by discharging the water containing the pollutant from the cleaning sewage outlet pipe 12.

Further, the filtration device shown in FIG. 5 includes a center bar 3 a in the tank 1, and a plurality of branch bars 3 b are spirally attached in the vertical direction of the center bar. By rotating in the reverse direction and agitating the inside of the tank with a branch bar, contaminants adhering to the filter medium 2 are removed (Patent Document 2).
According to the filtering devices described in Patent Documents 1 and 2, since the filtering medium is completely stirred in the filtering tank in the cleaning operation, the filtering medium is compared with the above-described method of laminating the plurality of filtering mediums in layers. Can be washed thoroughly.

Japanese Utility Model Publication No. 54-45465 JP-A-1-281115

However, the filtering devices described in Patent Documents 1 and 2 have the following problems.
That is, in the case of the filtration device described in Patent Document 1, a plate-like member extending in the vertical direction in the container is used as the stirring blade. During the normal filtering operation, the filtering material is deposited on the partition plate, so that most of the stirring blades are buried in the filtering material.
If the shaft is rotated to start the cleaning operation from this state, the filter medium around the stirring blade becomes a resistance and an excessive load is applied to the drive mechanism, which may damage the drive mechanism.

In addition, because the stirring blade is long in the vertical direction and has a so-called cantilever structure fixed at the lower part, an excessive moment is generated in the lower part (fixed end) of the stirring blade due to the load acting on the stirring blade from the filter medium during rotation. May act, and the lower part of the stirring blade may be damaged.
Furthermore, since the filter medium is stirred by a plurality of long stirring blades, the number of times the filter medium collides with the stirring blade increases, and the filter medium may be damaged by the impact.
Similarly, in the case of the filtering device disclosed in Patent Document 2, a plurality of branch rods 3b are spirally attached in the vertical direction (eight in the figure), so that the filter medium that collides with the branch rods during rotation is damaged. There is a possibility that.

  In view of such problems, the present invention has an object to provide a filtration device that can reduce the load applied to the stirring member in the cleaning operation and can reduce the damage of the filter medium due to the collision with the stirring member. To do.

  The filtration device of the present invention includes a filtration tank, a rotation shaft that is rotatably supported around the axis in the filtration tank, and a stirring rod that is fixed to the rotation shaft and stirs the filter medium to which contaminants are attached. As a stirring bar, the lower stirring bar fixed at right angles to the rotation axis at a position where the filtering medium is buried in the filtering medium in a state where the filtering medium is deposited in the filtering tank, and the filtering medium in a state where the filtering medium is deposited in the filtering tank. An upper stirring rod fixed at right angles to the rotation axis in a position not buried in the material, and at least part of the filtering material is buried in the filtering material in a state where the filtering material is deposited in the filtration tank. A stirring blade extending downward is provided.

According to the filtration device of the present invention, since at least a part of the stirring blade is disposed so as to be buried in the filtering material, it is possible to suppress the resistance that the entire upper stirring bar and the stirring blade receive from the filtering material in the cleaning operation, The stirring rod and the stirring blade can be smoothly rotated.
Thereby, especially the load given to the stirring rod and the stirring blade from the filter medium at the start of the cleaning operation can be reduced, and the possibility of breakage of the stirring rod and the stirring blade can be suppressed. Moreover, the frequency | count that a filter medium collides with a stirring blade can be reduced, and the failure | damage of a filter medium can be reduced.

Further, since the upper stirring rod and the stirring blade rotate smoothly at the start of the cleaning operation, a rotational force around the axis can be easily applied to the upper part of the accumulated filter medium. As a result, the filter medium starts to rotate around the axis from the upper part, and gradually the central part and the lower part also begin to rotate. Once the entire filter medium begins to rotate, the wash water (clean water for washing that does not contain contaminants) that has received the rotational force of the lower stirring rod that is buried in the filter medium rises and convects in the filter tank. Since it starts, the filter medium can be sufficiently stirred by the rotational flow around the axis and the convection in the vertical direction.
In this specification, the operation of introducing circulating water into the filtration tank and removing the pollutants using the filter medium deposited in the filtration tank is referred to as “filtration work”, and the inside of the filtration tank is stirred and filtered. The operation for removing the pollutants adhering to the material is called “cleaning operation”.

It is a side view which shows the external appearance of a filtration apparatus. It is a longitudinal cross-sectional view which shows the internal structure of a filtration apparatus. It is a top view (a)-(d) which shows the structure of a wire mesh. It is a longitudinal cross-sectional view which shows the internal structure of the conventional filter apparatus. It is a longitudinal cross-sectional view which shows the internal structure of the conventional filter apparatus.

As shown in FIG.1 and FIG.2, the filtration apparatus 10 of this invention is equipped with the filtration tank 20, the rotating shaft 50, the stirring rod 60, the stirring blade 70 grade | etc.,.
The filtration tank 20 has a substantially cylindrical shape whose top and bottom are closed, and is made of metal such as aluminum or stainless steel or resin such as FRP (fiber reinforced plastic). It should be noted that galvanization may be appropriately performed depending on the water quality of the facility using the filtration device 10.
An upper opening 21 is provided in the upper part of the side surface of the filtration tank 20 and will be described in detail later. In the upper opening 21, circulating water is introduced into the filtration tank 20 in the filtration operation, and contaminants are introduced in the cleaning operation. An upper pipe 22 for discharging the circulating water to be included outside the filtration tank 20 is attached.
A discharge pipe 24 is connected to the upper pipe 22 via a first valve 23a.

A lower opening 25 is provided in the lower portion of the side surface of the filtration tank 20, and will be described in detail later. In the lower opening 25, circulating water after filtration is filtered out of the filtration tank 20 in the filtration operation and in the washing operation. A lower pipe 26 for introducing the washing water into the filtration tank 20 is attached.
A circulation pipe 27 is connected to the lower pipe 26 via a second valve 23b.
The upper pipe 22 and the lower pipe 26 are connected to each other through a third valve 23c at a substantially central portion of the filtration tank 20, and a central pipe 28 is connected to the third valve 23c.
During the filtering operation, the circulating water discharged from the water storage tank (not shown) passes through the central pipe 28, and the circulating water passing through the central pipe 28 passes through the third valve 23c and the first valve 23a. Operation enters the filtration tank 20 through the upper tube 22. Further, during the cleaning operation, the cleaning water passes through the central pipe 28, and the cleaning water that has passed through the central pipe 28 is filtered through the lower pipe 26 by the operation of the third valve 23c and the second valve 23b. Enter tank 20.

An inspection port 29 is provided in the upper part of the side surface of the filtration tank 20 so that the inside of the filtration tank 20 can be visually inspected during a filtering operation and a cleaning operation. While the inspection port 29 is not used, it is closed with a lid 30.
A filter material take-out port 31 is provided at the lower side of the side surface of the filter tank 20 so that it can be used for exchanging old filter material A or the like. While the filter medium outlet 31 is not used, it is closed with a lid 32.
The upper part of the filtration tank 20 is closed with a lid 33. A motor 35 as a rotary shaft drive mechanism 34 is attached to the center of the lid, and an air vent pipe 36 for extracting air from the filtration tank 20 and a pressure gauge 37 for measuring the pressure in the filtration tank 20 are provided. It is attached.

A wire mesh 38 is attached to the lower inside of the filtration tank 20. As shown in FIG. 3, the metal mesh 38 has a three-layer structure in which a net retainer 39, a filtration net 40, and a net support 41 are arranged in order from the top. When viewed from the side as shown in FIG. It has a recessed shape. A lower space 42 is formed below the wire mesh 38.
The net receiver 41 is a circular thin plate member, and two types of openings 41b and 41c having a large diameter and a small diameter are formed in each region 41a divided into four arcs. By making the diameters of the openings into two types, large and small, the strength of the net receiver 41 as a whole can be increased compared to the case where only the large-diameter opening is used.
The filter net 40 is arranged on the upper surface of each area 41 a of the net receiver 41 in a state of being divided into four arcs, and is fixed with bolts and nuts by a net retainer 39. The mesh of the filter net 40 is set smaller than the diameter of the filter medium A so that the filter medium A does not pass through.
The filter medium A is deposited on the upper surface of the wire mesh 38, and the circulating water during the filtration operation passes through the wire mesh 38 downward, and the cleaning water during the cleaning operation passes through the wire mesh 38 upward. As described above, since water pressure is applied to the wire net 38 from above and below, metal fatigue may occur due to long-term use, and the filter net 40 may be damaged. However, the filter net 40 shown in the present embodiment is 4 Since it is divided into two small pieces, it is possible to easily replace the damaged filter net 40 through the filter material outlet 31.
In FIG. 2, the density of the filter medium A is drawn sparse for easy understanding. In the present embodiment, sand is used as the filter medium A. However, the present invention is not limited to this, and a known adsorbent such as granular activated carbon, ceramics, calcium sulfite, or the like may be used.
A shielding plate 43 is attached above the inside of the filtration tank 20 and in the vicinity of the upper opening 21. The shielding plate 43 is a cylindrical member that expands downward, and is joined to the inner surface of the filtration tank 20 at the lower end thereof. The shielding plate 43 has a function of shielding the filter medium A rotating and convection in the filtration tank 20 from flowing into the upper tube 22 from the upper opening 21 during the cleaning operation.

The rotary shaft 50 is a rod-like member extending vertically in the center of the filtration tank 20, and is connected to the rotary shaft drive mechanism 34 at the upper end thereof, and the lower end thereof is rotatable around the axis on the lower surface of the filtration tank 20. It is supported.
The stirring rod 60 is a rod-shaped member that is fixed to the rotating shaft 50 and that stirs the filter medium A to which the pollutant adheres, and includes a lower stirring rod 61 and an upper stirring rod 62.
The lower stirring bar 61 is fixed orthogonally to the rotation shaft 50 at a position where the filter medium A is buried in the filter tank 20 and buried in the filter medium A. The “state in which the filtering material A is accumulated in the filtration tank 20” refers to a state in which the filtering material A is deposited almost stationary on the wire mesh 38 when performing the filtering operation. In FIG. 2, the position indicated by the symbol X is the upper surface of the filter medium A, and below this position is the “position buried in the filter medium A”.
In the present embodiment, two lower stirring bars 61 are attached. The number of the lower stirring bar 61 is not particularly limited, but if it is too large, it is easy to receive resistance when starting the cleaning operation, and the number of times the filter medium A collides with the lower stirring bar 61 increases. Since the possibility of damaging the filter medium A due to the impact of the filter medium 2 is increased, it is preferable to arrange two filters so that the lower part and the center part of the filter medium A can be stirred while the filter medium A is accumulated in the filter tank 20.

The upper stirring rod 62 is fixed orthogonally to the rotation shaft 50 at a position where the filter medium A is deposited in the filter tank 20 and is not buried in the filter medium A. That is, it is fixed to the rotating shaft 50 above the position indicated by the symbol X.
The stirring blade 70 is a rod-like member extending downward from the upper stirring rod 62 so that at least a part of the filtering material A is buried in the filtering material A in a state where the filtering material A is accumulated in the filtration tank 20. That is, it is attached so that at least a part of the stirring blade 70 is positioned below the position indicated by the symbol X, and in this embodiment, the lower part of each of the three stirring blades 70 is below the symbol X. Is located. The number of the stirring blades 70 is not particularly limited. However, if the number of the stirring blades 70 is too large, it is easy to receive resistance when starting the cleaning operation, and the number of times the filter medium A collides with the stirring blades 70 increases. In such a case, it is preferable to arrange three filters so that the three parts in the vicinity of the outer peripheral edge and the central part of the filter medium A (near the rotating shaft 50) and the middle of these two parts can be stirred.

Next, the filtering operation will be described by taking as an example the case where the filtering device 10 is applied to a circulating water purification device of a hot spring.
First, the circulating water discharged from the bathtub (not shown) has its hair and the like removed by a hair catcher (not shown) and further injected with a disinfectant, and then reaches the filtration device 10.
In the filtration device 10, the circulating water first passes through the central pipe 28, and enters the filtration tank 20 from the upper opening 21 through the upper pipe 22 by operating the third valve 23 c and the first valve 23 a. The operation of each of the valves 23a to 23c may be performed manually by a person in charge of the cleaning / filtering operation or may be automatically performed by a machine operation.
The filter tank 20 is stationary with the filter medium A accumulated, and the air in the filter tank 20 is discharged to the outside from the air vent pipe 36 as the circulating water level rises. Eventually, the circulating water reaches almost the upper part of the filtration tank 20. In addition, the state (the presence or absence of clogging) of the filter medium A etc. can be detected by measuring the pressure in the filtration tank 20 with the pressure gauge 37.
The circulating water permeates the filter medium A downward, and is filtered by adsorbing the fine contaminants that could not be removed by the hair catcher to the filter medium A.
The circulating water that has passed through the wire mesh 38 reaches the lower space 42, passes through the lower pipe 26, passes through the circulation pipe 27 by the operation of the second valve 23 b and the third valve 23 c, and if necessary, a heat exchanger (not shown). It is heated to an appropriate temperature and reaches the bathtub for reuse.

Next, the cleaning operation by the filtration device 10 will be described.
First, washing water is put into the filtration tank 20 from the lower opening 25 through the central pipe 28 and the lower pipe 26 by operating the third valve 23c and the second valve 23b.
Next, the filter medium A, which has been in a substantially stationary state, is slightly floated by causing the washing water to flow backward from the lower side to the upper side in the filter tank 20. Thereby, the load at the time of driving of the motor 35 can be reduced.
Next, when the motor 35 is driven and the rotating shaft 50 is rotated, the upper stirring rod 62, the stirring blade 70, and the lower stirring rod 61 start to rotate integrally.

Here, since the entire upper stirring rod 62 and the upper part of the stirring blade 70 are not buried in the filter medium A, the resistance of the filter medium A can be suppressed and the filter can be smoothly rotated.
By rotating the upper stirring rod 62 and the stirring blade 70 smoothly, a rotational force around the axis can be easily applied to the upper portion of the filter medium A in a slightly floating state. The filter medium A starts to rotate around its axis from the upper part, and gradually, the central part and the lower part of the filter medium A also start to rotate.
Once the entire filter medium A begins to rotate, the wash water that receives the rotational force of the two lower stirring rods 61 rises and starts convection, so that filtration is performed by rotating around the axis and convection in the vertical direction. The material A will be sufficiently stirred.
The agitated filter media A rub against each other, and the adhering contaminants are peeled off.
The pollutant separated from the filter medium A is discarded together with the washing water through the upper opening 21 through the upper pipe 22 and through the discharge pipe 24 by the operation of the first valve 23a and the third valve 23c.

In addition, the filtration apparatus 10 of this invention can be utilized for the system which filters and reuses an impurity and a pollutant while circulating not only the said hot spring but a pool, a household bathtub, and other water.
Moreover, you may arrange | position the filtration apparatus 10 only with respect to several bathtub circulation systems, or multiple. For example, even if the bathtub for male hot water and the bathtub for female hot water are separate bathtub circulation systems, a single filtration device 10 common to each bathtub circulation system may be arranged. Large-scale hot spring facilities often have open-air baths and jet baths for both men's and women's baths. In this case, multiple bathtub circulation systems are required, but even in this case one or more for each bathtub circulation system What is necessary is just to attach the filter apparatus 10 of a stand.

  INDUSTRIAL APPLICABILITY The present invention can reduce the load applied to the stirring member in the cleaning operation of the filtration device, and can reduce the damage of the filtering material due to the collision with the stirring member, and has industrial applicability.

DESCRIPTION OF SYMBOLS 10 Filtration apparatus 20 Filtration tank 50 Rotating shaft 60 Stirring bar 61 Lower stirring bar 62 Upper stirring bar 70 Stirring blade

Claims (1)

A filtration tank;
A rotating shaft supported rotatably around the axis in the filtration tank;
In a filtration apparatus comprising a stirring rod that is fixed to the rotating shaft and stirs a filter medium to which contaminants adhere,
As the stirring bar, a lower stirring bar fixed perpendicularly to the rotation shaft at a position where the filter medium is buried in the filter medium in a state where the filter medium is deposited in the filter tank, and the filter medium is deposited in the filter tank. An upper stirring bar fixed perpendicularly to the rotation axis at a position where the filter medium is not buried in the state,
A filtration apparatus comprising a stirring blade extending downward from the upper stirring bar so that at least a part of the filter medium is buried in the filter medium in a state where the filter medium is accumulated in the filtration tank.

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