JPH1033912A - Filtering method and apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily eliminate the clogging of filter elements for filtering raw water, enhancing the filtering treatment work efficiency of raw water and to reduce the of cleaning work of the filter elements. SOLUTION: In a filtering method filtering raw water W by a filter element 4 having a large number of through-holes provided to the peripheral surface part 4A, the raw water W is filtered by the filter element 4 and at least one of the filter element 4 and washing water jet nozzles 8 is rotated so that the filter element 4 is relatively rotated in the peripheral direction of a peripheral surface part 4A of the filter element 4 with respect to the washing water jet nozzles 8 while washing water is jetted to the peripheral surface part 4A of the filter element 4 from the washing water jet nozzles 8 arranged in opposed relation to the filter element 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for efficiently filtering various types of water (raw water) such as industrial wastewater containing foreign substances, sewage, snowmelt, or washing water used for washing clothes and the like. About.

[0002]

2. Description of the Related Art Conventionally, specific examples of a filtering device are described in Japanese Patent Publication No. 18890/1993, Japanese Utility Model Publication No. 5-10884, and Japanese Utility Model Publication No. 63-13777. The conventional filtration devices described in these publications each perform a desired raw water filtration treatment using a filtration element formed in an appropriate shape such as a cylindrical shape or a cage shape. .

[0003]

However, the above-mentioned conventional filtering apparatus has the following disadvantages.

That is, in order for the raw water to be properly filtered by the filtration element, it is necessary to reduce the diameter of a through hole provided in the filtration element to a certain degree. Foreign matter in the raw water enters the minute through-holes of the element, so that the so-called filter element is clogged. In particular, such clogging becomes more remarkable when filtering used washing water or the like containing a large amount of fibers such as lint.

[0005] However, in the conventional filtering device, no means for preventing the clogging of the filtering element as described above is actually taken. Therefore, conventionally, it has been necessary to perform a filtration process of raw water to some extent, and if the filtration element is clogged, interrupt the filtration process and clean the filtration element. As a result, conventionally, the filtration operation has to be frequently interrupted due to clogging of the filtration element, and the efficiency of the filtration operation of the raw water has deteriorated. Further, the cleaning work for eliminating the clogging of the filtration element is very troublesome, and the labor burden is also large.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and it is possible to prevent the filter element for filtering raw water from being easily clogged, thereby improving the efficiency of the raw water filtration process. It is an object of the present invention to improve the filter performance and reduce the labor burden of the cleaning operation of the filter element.

[0007]

DISCLOSURE OF THE INVENTION In order to solve the above problems, the present invention employs the following technical means.

According to a first aspect of the present invention, there is provided a filtering method for filtering raw water through a filtering element having a large number of through-holes formed in a peripheral surface thereof, wherein the raw water is filtered by the filtering element. On the other hand, while injecting washing water to the peripheral surface of the filtration element from the washing water injection nozzle arranged opposite to the filtration element, the filtration element It is characterized in that at least one of the filtration element and the washing water injection nozzle is rotated so as to relatively rotate in the circumferential direction.

In the present invention, when the raw water is filtered by the filtration element, the washing water is jetted to the peripheral surface of the filtration element, so that the filtration operation of the raw water is not interrupted at all. Foreign matter that has entered the through-hole can be removed by the jetting action of the washing water, and the filter element can be prevented from being clogged. When the washing water is being sprayed onto the peripheral surface of the filtration element, the washing water is rotated around the peripheral surface of the filtration element because the filtration element is relatively rotated in the circumferential direction with respect to the washing water injection nozzle. , And clogging can be prevented from occurring at any point on the peripheral surface of the filtration element.

As described above, according to the present invention, since the clogging of the filtration element can be prevented while performing the filtering operation of the raw water, the filtration element can be easily formed in a short period of time unlike the related art. Clogging can be avoided, and the filtration of raw water can be continuously performed for a long time. Therefore, according to the present invention, a special effect that the efficiency of the raw water filtration treatment can be improved can be obtained. Further, the labor for cleaning the filter element can be reduced, and the labor burden of the cleaning operation can be reduced. Furthermore, in the present invention, as a means for preventing clogging of the entire peripheral surface of the filtration element, the filtration element is rotated relative to the cleaning water injection nozzle. It is not necessary to provide a large number along the line, and the cost of parts for the washing water injection nozzle can be reduced. Also, in a region of the peripheral surface of the filtration element where the washing water is not jetted, an appropriate filtration treatment of the raw water can be performed.

In a preferred embodiment of the present invention, the washing water injection nozzle is provided so as to inject washing water in a direction opposite to a direction in which raw water passes through a through hole of the filter element. be able to.

According to such a configuration, the jetting direction of the washing water jetted from the washing water jet nozzle is opposite to the direction in which the raw water passes through the through-hole of the filtration element.
The washing water can be made to act so as to push back foreign matter entering the through-hole of the filtration element in a direction opposite to the entry direction. The same applies to a foreign substance that is caught in the through hole. Therefore, the efficiency of removing foreign substances clogged in the filtration element can be improved. Further, as described above, if the foreign matter clogged in the filter element is pushed back in a direction opposite to the direction of entry into the through-hole, the foreign matter may be mixed into the treated water filtered by the filter element. It can be properly prevented.

According to a second aspect of the present invention, a filtration element having a large number of through-holes in a peripheral surface portion, a casing accommodating the filtration element therein, and flowing raw water into the filtration element. A raw water inlet, and a treated water discharge port for discharging water that has passed through the through-hole from the inside of the filtration element to the outside of the casing, wherein the filtration device has a peripheral surface portion of the filtration element. It is characterized by comprising at least one or more washing water injection nozzles for injecting washing water to the outer peripheral surface, and filter element driving means for rotating the filter element in the circumferential direction.

In the present invention, the raw water can be filtered by the filtration element by flowing the raw water from the raw water introduction port into the filtration element housed in the casing. It can be discharged to the outside of the casing through a discharge port. Then, while performing such a series of filtration processes, it is possible to inject cleaning water from the cleaning water injection nozzle to the outer peripheral surface of the peripheral surface of the filtration element while rotating the filtration element in the circumferential direction. it can. Therefore, while preventing the clogging of the peripheral surface portion of the filtration element by the spraying action of the washing water, the filtration treatment of the raw water using the filtration element can be continuously performed. The same effect as obtained can be expected. Further, while the raw water is filtered by flowing from the inside of the filtration element to the outside through the through-hole of the filtration element, the direction of jetting of the washing water jetted on the outer peripheral surface of the peripheral surface portion of the filtration element is: Since the direction is opposite to the above, foreign matter clogged in the filtration element can be returned to the inside of the filtration element by the washing water, and the foreign matter can be prevented from being mixed into the filtered treated water. Further, the efficiency of removing foreign substances clogged in the filtration element can be improved.

In a preferred embodiment of the present invention, the cleaning water injection nozzle can be configured to be capable of injecting cleaning water at predetermined time intervals by setting a timer.

According to such a configuration, the injection of the washing water to the filtration element is performed intermittently at predetermined time intervals set by a timer. Therefore, compared with the case where the washing water is always jetted, the consumption of the washing water is reduced, which is economically advantageous. In addition, as compared with the case where the worker performs the spraying of the washing water by manual operation, the labor of the work management by the worker can be omitted, and the advantage that the work can be automated can be obtained.

In another preferred embodiment of the present invention,
The washing water injection nozzle is configured to irrigate the washing water so that a stream of the washing water collides with the peripheral surface of the filtration element when the treatment water filtered by the filtration element is present around the outer periphery of the filtration element. It is possible to adopt a configuration in which injection is performed.

Such a configuration is suitable for a case where the filtration device is used so that the treated water is stored in the casing. That is, for example, when the suction negative pressure is applied to the casing by connecting the suction side of the pump to the treated water discharge port and the raw water is introduced into the casing from the raw water inlet, It is necessary to operate the filtration device while the raw water or treated water is contained in the casing in a full or almost full state so that the raw water can be appropriately introduced into the casing by the pressure action,
In such a case, the outer periphery of the peripheral surface of the filtration element may be filled with the treated water filtered by the filtration element. However, even in such a case, the cleaning water injected from the cleaning water injection nozzle is
Since a water flow colliding with the peripheral surface of the filtration element is generated, the filtration element can be appropriately cleaned and its clogging can be prevented.

In another preferred embodiment of the present invention,
The raw water inlet is provided inside the filtration element from a tangential direction of the peripheral surface of the filtration element so as to generate a vortex flow inside the filtration element that collects foreign substances contained in the raw water at the center inside the filtration element. And a drain drain opening communicating with a drain pipe line provided with an open / close valve is provided at a substantially central portion of the bottom of the filtration element. It can be.

According to such a configuration, the raw water is filtered by the filtration element inside the filtration element while generating a vortex which has the effect of collecting foreign substances contained in the raw water at the center inside the filtration element. It can be filtered continuously. Due to the generation of the above-mentioned spiral flow,
If the foreign substances contained in the raw water are collected at the central part inside the filtration element, the chance that the foreign substances contained in the raw water come into contact with the peripheral surface of the filtration element can be reduced, and the filtration element is clogged. The effect is obtained that the risk can be further reduced and an efficient filtration process can be performed over a long period of time. When performing such a series of filtration processes, the on-off valve provided on the drain pipe is kept closed. However, the filtration process of the raw water is performed for a predetermined time, and a certain amount of foreign matter is removed by the filtration element. When the liquid accumulates in the central portion of the inside of the container, the foreign matter can be collectively removed from the drain pipe by opening the open / close valve. Therefore, the collection and disposal of foreign matter is also facilitated.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be specifically described below with reference to the drawings.

FIG. 1 is a front sectional view showing an example of a filtering device A according to the present invention. FIG. 2 is a sectional view taken along line X1-X1 of FIG. FIG. 3 is a cross-sectional view of a main part taken along line X2-X2 in FIG.

In FIG. 1, a filter device A includes a casing 3 having a raw water inlet 1 and a treated water outlet 2, a funnel-shaped filter element 4 provided in the casing 3, and a bottom portion of the filter element 4. , A rotary drive mechanism 7 for rotating the filtration element 4, a washing water injection nozzle 8 provided, for example, at two locations on the peripheral wall of the casing 3, and other components described below. It is configured.

The casing 3 is made of, for example, stainless steel excellent in rust prevention and the like, and is constituted by connecting two upper and lower casing bodies 3a and 3b formed in a substantially cylindrical shape to each other via a partition plate 30. Have been. Further, a lid 31 that closes an upper opening of the casing 3 is attached to an upper portion of the casing 3. Thereby, the space chamber 32 above the partition plate 30 in the inside of the casing 3, except for the raw water introduction port 1 and the treated water discharge port 2, is in a sealed or substantially sealed state separated from the outside. It is possible to set. If the space chamber 32 is set to a closed or substantially closed state, the raw water W is supplied from the raw water inlet 1 into the casing 3 by applying a pump suction negative pressure of the pump P to the treated water outlet 2 as described later. Can be inhaled.

However, the lid 31 is provided with an air vent valve 33. This air release valve 33
Is always in a closed state, but if the air bleeding valve 33 is opened, the closed or substantially closed state of the space chamber 32 in the casing 3 can be released. This serves to promote the drainage of the water in the space chamber 32 when the water is drained from the drain pipe 5.

The raw water introduction port 1 is a part for introducing desired raw water W to be treated into the casing 3, and is open at the upper inner peripheral wall surface of the casing 3. Specifically, the opening position is above the filtration element 4. The raw water W is located at the position where the raw water inlet 1 is formed.
Is connected to a short tubular section 10 having a flange 10a for connecting the supply pipe B1. Therefore, the raw water W is introduced into the casing 3 from the raw water inlet 1 through the supply pipe B1 and the pipe portion 10.

As shown in FIG. 2, the axial direction of the tubular body 10 is provided so as to substantially coincide with the tangential direction of the cylindrical casing 3. For this reason, the raw water W introduced into the casing 3 at a constant flow rate from the raw water inlet 1 forms a predetermined spiral flow inside the casing 3, particularly inside the filter element 4 as described later.

In FIG. 1, the treated water discharge port 2 is a part for discharging treated water that has passed through the filtration element 4 and is filtered out of the casing 3, and is opened to the inner peripheral wall of the casing 3. ing. At a position where the treated water discharge port 2 is formed, a short tubular body 20 having an electric open / close valve 21 is connected, and this tubular body 20 is connected to a suction port Pa of the pump P by a pipe. ing.

The filter element 4 is preferably made of a material having excellent rust resistance, such as stainless steel, and is connected to a cylindrical portion 4a having a smaller diameter than the casing 3 and a lower portion of the cylindrical portion 4a. Inverted conical tapered portion 4b
Is provided. Peripheral surface portion 4A of the filtration element 4
Among them, the constant width region W has a diameter of 0.5 m, for example.
A large number of through holes 40 of about m are formed. In contrast,
The through holes 40 are not provided in regions other than the above. The upper part of the filter element 4 is locked by a step 34 projecting from the inner peripheral wall of the casing 3, and the filter element 4 can rotate in the circumferential direction while sliding on the step 34. ing.

The drain pipe 5 has a series of pipes 50 communicating with the bottom opening 41 of the filter element 4. The first pipe 5 a is connected directly to the filter element 4. And a curved second pipe 5b connected to the first pipe 5a. The drain pipe 5 is provided with an opening / closing valve 6 for opening and closing the pipe line 50. The opening / closing valve 6 is set to a closed state in a normal state where the raw water W is being filtered. You.

The rotation drive mechanism 7 applies a rotational force to the first pipe 5a of the drain pipe 5,
The filter element 4 connected to the first pipe 5a
Is a mechanism for rotating in the circumferential direction. In particular,
The rotation drive mechanism 7 has a motor M attached to the outside of the casing 3. The rotation drive force of the sprocket 70 of the drive shaft of the motor M is attached to the first pipe 5 a via a chain 72. Is transmitted to the sprocket 71 provided. The first pipe 5a is
The first pipe 5a is rotatably supported around a central axis in a longitudinal direction (vertical direction) of the first pipe 5a by two upper and lower bearing members 51, 51a. On the other hand, the second pipe 5b of the drain pipe 5 is attached so as not to rotate with the rotation of the first pipe 5a.

As shown in FIG. 3, the rotary drive mechanism 7 rotates the filter element 4 in a direction (arrow N2 direction) opposite to the direction in which the raw water W flows (arrow N1 direction) in the filter element 4. Is set to The rotation drive mechanism 7 is configured to be able to be driven for a predetermined time at predetermined time intervals set in advance by a timer setting device (not shown).

The cleaning water injection nozzle 8 discharges the cleaning water supplied at a constant water pressure through the pipe 80, and injects the cleaning water to the outer peripheral surface of the peripheral surface 4A of the filter element 4. So as to be fixed to the peripheral wall of the casing 3. The washing water injection nozzle 8 is
Similarly to the above-mentioned rotary drive mechanism 7, it is configured such that the washing water can be jetted for a predetermined time at a predetermined time interval also set by the timer setting device. Only when the element 4 rotates, the washing water can be discharged in synchronization with the rotation.

In the present embodiment, the two cleaning water injection nozzles 8 are provided vertically displaced from each other, and the cleaning water is sprayed by these two cleaning water injection nozzles 8 over the entire width W of the through hole 40. It is configured to be able to jet. However, in the present invention, it is necessary to increase the number of the cleaning water injection nozzles 8 as the formation width W of the through hole 40 increases, regardless of the specific number of the cleaning water injection nozzles 8. Further, as the washing water, it is possible to appropriately use general tap water having a small amount of impurities, or treated water obtained by performing a filtration treatment using the filtration device A, and a specific type of the washing water is particularly preferable. Not limited. The water pressure of the washing water injected from the washing water injection nozzle 8 is, for example, about 6 kg / cm ² , and the opening diameter of the tip of the washing water injection nozzle 8 is about 2 mm. The distance from the tip of the washing water injection nozzle 8 to the peripheral surface 4A of the filtration element 4 is set to, for example, about 20 mm.

Next, a method of filtering the raw water W using the filtering device A having the above configuration will be described.

First, the pump P is operated with the on-off valve 6 of the filtering device A closed. The pump P is provided on the downstream side of the filtration device A.
By setting the space chamber 32 in a closed or substantially closed state, the pump suction negative pressure of the pump P can be applied to the raw water inlet 1 and the supply pipe B for the raw water W accurately. Therefore, by driving the pump P, the raw water W
From the raw water inlet 1 into the casing 3.

The raw water W introduced into the casing 3 as described above flows in the tangential direction of the cylindrical casing 3 and the funnel-shaped filtration element 4. A high-speed spiral flow spirally flows along the inner peripheral surface and the inner peripheral surface of the filter element 4. Therefore, the raw water W forming the spiral flow is sequentially filtered through the through holes 40 of the filter element 4, and
The filtered treated water passes through the treated water discharge port 2 and the pump P
Sent to Since the processing liquid after the filtration processing is sent to the pump P, it is possible to eliminate the possibility that foreign substances contained in the raw water enter the pump P and prevent the pump P from malfunctioning. This is advantageous.

On the other hand, when the raw water W is introduced into the casing 3 by utilizing the suction negative pressure of the pump P, the raw water W and the treated water obtained by filtering the raw water W are filled in the space 32 in the casing 3. The filter element 4
In the vicinity of the inner central portion C, a spiral flow having a lower speed is formed than in the vicinity of the inner peripheral surface of the peripheral surface portion 4A of the filtration element 4.
At the position of the low-speed spiral flow, foreign matters m such as solids contained in the raw water W are collected. These foreign substances m
Among them, the one having a low specific gravity floats at the inner central portion C of the filtration element 4, and the one having a high specific gravity sinks downward, and passes through the bottom opening 41 so that the pipe 5
It will accumulate within zero. In this way, raw water W
The foreign matter m in the inside can be collected at the inner central portion C of the filtration element 4, and the possibility that the filtration element 4 is clogged by the foreign matter m in the raw water W can be further reduced. When the foreign matter m is sufficiently collected in the pipe 50 of the drain pipe 5, the opening / closing valve 6 may be opened appropriately to discharge the foreign matter m to the outside.

When the raw water W is being filtered as described above, the rotation driving mechanism 7 is periodically driven to rotate the filtration element 4 in the circumferential direction using a timer setting device. Cleaning water is sprayed from the cleaning water spray nozzle 8 during the rotation operation of the filtration element 4.
In the outer space of the filtration element 4 in the space chamber 32 in the casing 3, there is treated water having been subjected to the filtration treatment, but the washing water jetted from the washing water jet nozzle 8 has a constant pressure. It becomes a stream of the washing water having water and collides with the peripheral surface portion 4A of the filter element 4. Therefore, the foreign matter that has entered the through hole 40 of the filtration element 4 and is clogged is forcibly pushed back to the inside of the filtration element 4 by the water flow, and the clogging of the through hole 40 is prevented. Will be planned. In addition, since the filter element 4 rotates when the washing water is jetted in this way, clogging is prevented over the entire periphery of the peripheral surface 4A of the filter element 4.

As a result, in the filtering device A, as shown in FIG. 3, in the range of the certain region α where the cleaning water is injected, the filtering element 4 is subjected to the cleaning process, while the region other than the above-mentioned region is cleaned. Thus, the filtration processing of the raw water W is performed by the filtration element 4, and the filtration processing of the raw water W and the cleaning processing of the filtration element 4 are executed in parallel. Therefore, it is possible to continuously perform the filtration of the raw water W over a long period of time while preventing the filter element 4 from being clogged.

In the above-mentioned filtration treatment, since the raw water W comes into contact with the inner peripheral surface of the peripheral surface portion 4A of the filtration element 4 in a high-speed spiral flow state, the raw water W has a high flow velocity, so that this raw water W Foreign matter in W is less likely to be clogged in the filter element 4. Further, when the filtration element 4 is rotated, since the rotation direction of the filtration element 4 is opposite to the spiral direction of the raw water W, the relative flow velocity of the raw water W with respect to the inner peripheral surface of the filtration element 4 is further increased. Be faster.
Therefore, at the time of the rotation operation of the filtration element 4, it is possible to more completely prevent the filtration element 4 from being clogged.

FIG. 4 is an explanatory diagram showing an example of a water treatment system configured using the filtering device A having the above-described configuration.

The water treatment system shown in FIG. 3 has a configuration in which the above-mentioned filtration device A connected to a pump P is connected via a pipe B1 to a washing tub 9 for cleaning clothes, sheets and the like. A water regeneration treatment device D is connected to the subsequent stage of the pump P. As the water regeneration treatment device D, for example, a filtration device that enables removal treatment of impurities that are difficult to perform the filtration treatment with the filtration element 4 of the filtration device A is applied.

In the water treatment system having the above-described structure, the washing tub 9 can be used to wash laundry such as clothes and sheets, and dirty washing water (raw water) W can be filtered by the filtration device A. Although a large amount of fibers such as lint that easily clogs the filter element 4 is mixed in the washing water, the filtering device A is used for treating such washing water as described above. The foreign matter such as the fibers can be efficiently and appropriately removed from the washing water without easily causing the filter element 4 to be clogged by the jetting action. If the washing water in the washing tub 9 is directly supplied to the water regenerating apparatus D, the water regenerating apparatus D may become inoperable in a very short period of time. If a relatively large foreign substance such as the above is removed in advance, the processing capacity of the water regeneration treatment device D is maximized and the washing water regeneration process is performed efficiently without causing any trouble in the water regeneration treatment device D. be able to. If the water filtered by the water regeneration treatment device D is returned to the washing tub 9 via the pipe B2, the washing water can be reused. Therefore, washing water can be effectively used in the cleaning industry, and even if the washing water is to be discarded, the washing can be performed after performing the filtration process, which can be preferable from the viewpoint of protection of the natural environment.

In the above-mentioned water treatment system, a case where filtration of washing water is performed is taken as an example. However, such a water treatment system is not limited to this. For example, water or hot water used in pools and public baths is used. It is also possible to configure as a system for performing the filtration process. In the present invention, the type of raw water to be subjected to the filtration treatment is not limited, and various types of industrial drainage, household and domestic wastewater such as sewage, and various types of water such as snowmelt containing impurities such as mud are filtered. It is possible to apply.

In the above-described embodiment, the cleaning water injection operation from the cleaning water injection nozzle 8 and the rotation operation of the filtration element 4 are performed intermittently by setting a timer. However, the present invention is not limited to this. Not done. In the present invention, the above operations may be performed intermittently by means other than the timer setting, and the operation of injecting the washing water from the washing water injection nozzle 8 and the rotating operation of the filtration element 4 are always performed. It may be performed continuously.

Further, in the above embodiment, as a means for injecting the washing water uniformly around the entire peripheral surface of the filtering element, the washing element is fixed at a predetermined position while rotating the filtering element in the circumferential direction. However, since the washing water injection nozzle located outside the filtration element does not need to be rotated along a large movement trajectory, the structure of the filtration device can be made compact. The invention is not limited to this. In the present invention, contrary to the above embodiment, while the filtration element is fixed, the washing water injection nozzle is rotated in the circumferential direction of the peripheral surface of the filtration element, so that the entire periphery of the peripheral surface of the filtration element is removed. The washing water may be sprayed on.

Further, in the above-described embodiment, the vortex is generated in the filtration element 4 having the cylindrical portion 4a, so that the foreign matter in the raw water W is collected at the center of the inside of the filtration element 4. Although prevention of clogging can be prevented more thoroughly, the present invention is not limited to this. In the present invention, the raw water W may be simply filtered by flowing the raw water W into the filtration element 4. Further, in the above embodiment, the raw water W is made to pass through the through-hole 40 from the inside of the filtration element 4 to the outside. However, the present invention is not limited to this, and, contrary to the above embodiment, The filtration of the raw water W may be performed such that the raw water W passes through the through-holes 40 from the outside to the inside of the filtration element 4. In this case,
In order to cause foreign matter to enter the through hole 40 from the outside to the inside of the peripheral surface of the filtration element 4, the washing water injection nozzle is provided inside the filtration element 4, so that the periphery of the filtration element 4 is provided. It is preferable that the cleaning water is sprayed on the inner peripheral surface of the surface portion.

Further, in the above embodiment, the filtering element 4 has a cylindrical portion 4a at the upper part and an inverted conical tapered part 4b at the lower part. After all it is not limited to this. In short, the filtration element used in the present invention only needs to have a configuration in which a large number of through holes are provided in the peripheral surface. The peripheral surface of the filtration element may be tapered or non-tapered, and may be cylindrical, funnel-shaped, or prismatic, regardless of its shape.

In addition, the specific configuration of each part of the filtration device according to the present invention is not limited to the above-described embodiment, and can be variously changed in design. Similarly, the specific processing steps of the filtration method according to the present invention are not limited to the above embodiment, but can be variously changed. For example, in the above-described embodiment, the pump is provided at the subsequent stage of the filtering device. Conversely, by providing the pump at the preceding stage of the filtering device, the supply of raw water to the filtering device may be performed. .

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a filtration device according to the present invention.

FIG. 2 is a sectional view taken along line X1-X1 of FIG.

FIG. 3 is a sectional view taken along line X2-X2 in FIG. 1;

FIG. 4 is an explanatory diagram showing an example of a water treatment system configured using the filtration device shown in FIG. 1;

[Explanation of symbols]

 Reference Signs List 1 Raw water inlet 2 Treated water outlet 3 Casing 4 Filtration element 4A Peripheral surface part 5 Drain vent pipe 6 Open / close valve 7 Rotary drive mechanism (Drive means for filtration element) 8 Wash water injection nozzle 40 Through hole 41 Bottom opening 50 Pipe line

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location B01D 33/80

Claims (6)

[Claims] 1. A filtration method for filtering raw water through a filtration element having a plurality of through holes formed in a peripheral surface thereof, wherein the raw water is filtered by the filtration element while the raw water is being filtered by the filtration element. While injecting washing water from the arranged washing water injection nozzle to the peripheral surface of the filtration element, the filtration element is relatively rotated relative to the washing water injection nozzle in the circumferential direction of the peripheral surface. A filtration method comprising rotating at least one of a filtration element and a washing water injection nozzle. 2. The filtration method according to claim 1, wherein the washing water injection nozzle is provided so as to inject washing water in a direction opposite to a direction in which raw water passes through a through hole of the filtration element. 3. A filter element having a plurality of through holes formed in a peripheral surface thereof, a casing accommodating the filter element therein, a raw water inlet for flowing raw water into the filter element, A treated water discharge port for discharging water that has passed through the through-hole from the inside to the outside of the casing, and at least injecting washing water to the outer peripheral surface of the peripheral surface of the filter element. A filtration device comprising: one or more washing water injection nozzles; and a filter element driving means for rotating the filtration element in a circumferential direction thereof. 4. The filtering device according to claim 3, wherein the washing water injection nozzle is configured to be able to inject washing water at predetermined time intervals by setting a timer. 5. The washing water injection nozzle impinges a stream of washing water on the peripheral surface of the filter element when the treated water filtered by the filter element is present around the outer peripheral surface of the filter element. The filtering device according to claim 3, wherein the washing water is injected as described above. 6. The tangential direction of the peripheral surface of the filtration element so as to generate a vortex flow inside the filtration element that collects foreign substances contained in the raw water at a central portion inside the filtration element. A drain opening communicating with a pipe of a drain pipe provided with an open / close valve is provided at a substantially central portion of a bottom of the filtration element, while being configured to flow raw water into the filtration element. The filtration device according to any one of claims 3 to 5, which is provided.