JP7470377B2 - Filtration Equipment - Google Patents

Description

The present invention relates to a filtration device, and more specifically to a filtration device that can be easily used in emergencies such as disasters.

In recent years, there has been a tendency for situations to occur frequently where lifelines such as electricity, gas, and water are cut off due to earthquakes and typhoons, etc., and as a countermeasure, many households or neighborhood associations have begun purchasing and storing emergency generators for home use.

Examples of common household emergency generators include gasoline-powered generators and generators that use batteries to store electricity in advance.

On the other hand, in emergencies, it is extremely important to secure drinking water and other water for daily use. Securing water is extremely important in times of disaster. Generally, technology for securing water for daily use in emergencies includes technology related to filtration devices that use filters to obtain water for daily use from muddy water, etc.

However, gasoline generators run on gasoline, and because gasoline deteriorates if stored for long periods without being used, it must be stored with great care to maintain its quality. Furthermore, care must be taken when using the generator, such as draining any gasoline remaining in the generator after use. If gasoline is left in the generator for an extended period, the gasoline may deteriorate and cause problems that require the generator to be sent for repairs. In other words, storing gasoline is a huge effort, and if this is neglected, it is entirely conceivable that the generator will not work in the event of a disaster or other emergency.

On the other hand, with current technology, it is not easy to store enough power needed in an emergency using storage batteries that store electricity in advance, and once the stored power is used up, the battery becomes unusable, making it extremely difficult to store electricity in situations where there is no power, such as during a disaster. In addition, because storage batteries lose power even when not in use, there is an issue that electricity must be stored periodically. Meanwhile, technology for storing electricity using solar cells is currently being developed, but it is difficult to store electricity in bad weather, and there are issues with the stability of the power supply and storage.

Against this background, generators that use gas cartridges have been proposed. Gas cartridges contain flammable gas and are generally used as fuel for cooking appliances such as portable stoves, but energy can be obtained by burning the gas contained inside in the generator's internal combustion engine. Gas cartridges can be stored for longer periods than gasoline, and there is far less risk of the stored gas decreasing compared to the storage batteries mentioned above.

On the other hand, in filtration devices using the above filters, because a filter is used, once a certain amount of water has been processed, the filter must be replaced. This poses the problem that once the filter stock runs out, the device can no longer be used. In particular, since it is important for the filter to adsorb dirt, there is an issue that the filter consumption is very high compared to the amount of water to be filtered.

In view of the above problems, the present invention aims to provide an emergency filtration device that can be stored stably for long periods of time more easily and requires fewer consumables.

After extensive research into the above-mentioned issues, the inventors discovered that by combining a generator that uses a gas cartridge with a spring-loaded filter device, it is possible to provide an emergency filtration device that is simple in configuration, can be made compact, can be stored stably for long periods of time more easily, and requires fewer consumables, and thus completed the present invention.

That is, a filtration device according to one aspect of the present invention comprises a gas bottle generator and a spring-type filter device that is driven by the power generated by the gas bottle generator.

In addition, in this respect, although not limited thereto, it is preferable to provide a reverse osmosis membrane device downstream of the spring-type filter device.

In addition, in this respect, although not limited thereto, it is preferable that the spring filter device has a spring filter, a support member that supports the spring filter, a housing having an internal space that houses the spring filter and the support member, and a pump for sending the raw liquid to be treated into the internal space of the housing.

Furthermore, in this case, it is preferable that the internal space of the housing is divided into a lower space and an upper space by a support member, the lower space is connected to a pipe for the undiluted liquid, and the upper space is connected to a pipe for the filtrate.

In addition, although not limited to this aspect, it is preferable to have a hair collection device in front of the spring-type filter device.

As described above, the present invention provides an emergency filtration device that can be stored stably for long periods of time more easily and requires fewer consumables.

1 is a diagram showing an outline of the configuration of a filtering device according to an embodiment. FIG. 1 is a schematic diagram showing a cross section of a spring-shaped filter device according to an embodiment. FIG. 1 is a schematic diagram showing a spring-shaped filter according to an embodiment. FIG. 2 is a partial cross-sectional view of the spring-shaped filter according to the embodiment. FIG. 2 is a partially enlarged view of a spring-shaped filter according to an embodiment, in which a filter aid is attached to the periphery of the filter. FIG. 2 is a diagram showing an outline of piping of the spring-shaped filter device according to the embodiment.

The following describes in detail an embodiment of the present invention with reference to the drawings. However, the present invention can be embodied in many different forms, and the specific examples described in the following embodiments and examples can be modified and adjusted as appropriate, and are not limited to these.

(Filtration device)
FIG. 1 is a diagram showing the outline of the configuration of a filtering device (hereinafter referred to as "the device") 1 according to this embodiment. As shown in this figure, the device 1 includes a gas bottle generator 2 and a spring-type filter device 3 that is driven by the power generated by the gas bottle generator 2. A hair collection device 5 is disposed in front of the spring-type filter device 3, and a water source S to be treated is disposed in front of that. The flow of this process will be described later, but after coarse dust and the like are removed by the hair collection device 5 from the water source S via a pipe T1, fine impurities are removed by the spring-type filter device 3. The water purified by the device 1 is stored in a container C that stores water via a pipe T2.

In addition, this filtration device 1 is equipped with a reverse osmosis membrane device 4 downstream of the spring-type filter device 3. By using the reverse osmosis membrane device 4, it becomes possible to remove even finer impurities after removing finer impurities.

First, in this device 1, the gas cartridge generator 2 refers to a generator that can be driven by a gas cartridge as fuel and supply electricity.

The gas bottle used in this device 1 is a can-shaped gas bottle filled with flammable gas (hereinafter simply referred to as "gas") and can be completely sealed. The gas bottle is can-shaped, and once filled with gas, it can be stored for an extremely long period of time. The gas bottle has a stem at the tip, and by pressing this stem, the gas stored inside can be released to the outside (the internal combustion engine in the generator 2 in this device 1). Gas bottles are widely sold as fuel for portable stoves, so they are extremely easy to obtain, can be stored and preserved in large quantities, and there is little leakage of internal gas. More specifically, unlike storage batteries, there is very little loss of power, and unlike gasoline, there is significantly less risk of deterioration.

The cassette gas generator 2 used in the present device 1 is a device that can generate electricity by inserting the cassette gas and using the gas stored in the cassette gas as fuel. Specifically, the cassette gas is placed in a socket provided in the cassette gas generator 2, and the stem is pressed against the cassette gas to supply gas as fuel to the internal combustion engine in the cassette gas generator 2. Specifically, gas is introduced into the internal combustion engine in the cylinder generator 2, and the gas is ignited and burned. Then, a piston provided in the internal combustion engine vibrates back and forth in response to ignition and exhaust. Then, this reciprocating vibration can be converted into rotational motion to drive a generator such as a motor to generate electricity. The cassette gas generator 2 is not limited to any particular type as long as it can generate enough power to drive the pump of the spring-type filter device 3, and a commercially available cassette gas generator may be used. Note that, when the voltage to drive the pump is low, adjustments such as a booster device or connecting multiple generators in series to increase the voltage are necessary. As is clear from these descriptions, the cassette gas generator 2 is connected to the pump of the spring-type filter device 3 and is configured to supply power. In this device 1, by using the cassette gas generator 2 as described above, fuel can be stored stably for a long period of time, there is no risk of deterioration like with gasoline, and the need for complete use and maintenance is significantly reduced to prevent breakdowns caused by gasoline remaining in the device. In addition, unlike storage batteries, it does not take time to replenish power after it runs out, making it very easy to use. This maintenance friendliness and difficulty in obtaining fuel are very important in the event of a disaster. The power of this generator 2 can also be used to power a pump for pumping water from the water source S and a pump for supplying water to the reverse osmosis membrane device 4.

In addition, in this device 1, the spring-type filter device 3 is driven by the electricity generated by the gas cartridge generator as described above, and is the part that performs the main function of the filtering device.

Figure 2 shows a schematic cross-sectional view of the internal structure of the spring filter device 3 in this embodiment. As shown in this figure, the spring filter device 3 is composed of at least a spring filter 31, a support member 32 that supports it, and a housing 33 that houses the spring filter 31 and the support member 32. As will be clear from the description below, impurities remain on the outside of the spring filter 31, and liquid from which impurities have been removed (filtrate) passes through the inside. In other words, the outer space and the inner space are separated into the original liquid side and the filtrate side.

In addition, the spring type filter device 3 of this embodiment has a housing 33 that houses the spring type filter 31 and the support member 32, as described above. The support member 32 divides the internal space 34 in the housing 33 into two spaces, an upper space and a lower space, and the support member 32 functions as a partition plate. More specifically, the support member 32 has a plurality of holes, and the spring type filter 31 is inserted and installed in these holes, so that the internal space 34 in the housing 33 can be divided into a lower space 341 of the spring type filter (hereinafter simply referred to as the "lower space") and an upper space 342 of the spring type filter (hereinafter simply referred to as the "upper space"). In addition, in the spring type filter device 3, as described later, a filter aid 35 is applied around the spring type filter 31 during filtration. Figure 3 shows an outline of the spring type filter 31 according to this embodiment, Figure 4 shows a partial cross-section thereof, and Figure 5 shows an enlarged partial cross-section of the periphery of the spring type filter 31 during filtration. During filtration, the filter aid 35 is placed around the spring filter 31, and functions as a filter layer. Specifically, the lower space 341 and the upper space 342 of the filter are separated by the support member 32, and when the raw liquid to be treated moves from the lower space 341 side through the filter layer to the upper space 342 side, the undissolved impurities cannot pass through the filter layer and remain in the filter layer, and are removed from the raw liquid to be treated.

Here, we will explain the spring filter 31 of the spring filter device 3 again. The spring filter 31 in this device 1 is literally a spring-shaped filter. As shown in the above figure, the spring filter 31 is a filter in which wire material 311 is wound in a ring shape and overlaps with a specified gap between them, forming a spring shape. In addition, although not limited thereto, the wire material 311 of the spring filter 31 in the spring filter device 3 has protrusions 312 attached thereto to ensure the above-mentioned specified distance between adjacent wire portions, thereby stably ensuring the average gap length of the spring filter, or more specifically, the distance between the wire materials.

The average gap length (average distance between wires) of the spring filter in the spring filter device 3 can be set appropriately and is not limited, but is preferably in the range of 5 μm to 200 μm, and more preferably in the range of 10 μm to 150 μm. By setting it in this range, insoluble impurities to be removed from the liquid during filtration can be efficiently removed.

The material of the spring filter 31 in the spring filter device 3 is not limited as long as it can maintain its shape and the spring filter device 3 can achieve the desired effect. Examples of materials include metal materials such as simple metals such as copper, iron, titanium, and nickel, and alloys such as stainless steel, as well as resin materials such as polystyrene, polypropylene, and polyvinyl chloride.

The spring type filter 31 in the spring type filter device 3 can be easily realized by winding a single wire 311 in a circular spiral, but it is also possible to realize a similar structure by, for example, forming a circular laminate of multiple layers of wire or resin material with protrusions as described above. Even in this case, the spring type filter device 3 includes the spring type filter. That is, in the spring type filter device 3, the spring type filter 31 includes not only a wound body but also any structure of a laminate of stacked circular wires.

In addition, in this embodiment, the spring type filter 31 may be configured to have a core material 313 at the center of the wire material 311, and a pair of metal fittings for holding the core material 313 near both ends, as shown in the above figure. In this way, the wire material can be held more stably. In particular, it is preferable that one of the metal fittings is connected to the support member 32, while a screw groove is formed in order to reduce the gap between the support member 32. In this way, a screw groove that fits into the support member 32 is also formed in the support member 32, and by fitting them together, it is possible to stably fix the support member 32 and the spring type filter 31 and reduce the gap between the lower space 341 and the upper space 342.

As is clear from the above description, the spring-type filter device 3 may have a single spring-type filter 31, but it is preferable to have multiple spring-type filters 31. Specifically, it is preferable that multiple holes are formed in the support member 32, and that the spring-type filters 31 are inserted and fixed into each of the multiple holes. This makes it possible to improve the filtering efficiency.

In addition, in the present device 1, the lower space 341 and upper space 342 of the spring filter 31 in the housing 33, among the internal space 34 in the housing 33, are respectively equipped with a raw liquid tube 36 and a filtrate tube 37. This makes it possible to supply the raw liquid containing the impurities to be treated to the lower space 341, and to discharge the filtrate from which the impurities have been filtered out from the upper space 342 through the filtrate tube.

As will be clear from the description below, in the spring-type filter device 3 of this device 1, it is preferable to connect the raw liquid pipe 36 and the filtrate pipe 37 to form a circulation path so that the filter aid-containing water can be circulated within the device until the filter aid is layered around the spring-type filter 31 and the water is in a state where it can be sufficiently filtered. It is preferable that this circulation path is equipped with a valve for controlling the opening and closing of the path and a pump as a power source for circulation. An outline of the pipe connections of the spring-type filter device 3 is shown in Figure 6.

As shown in this figure, in the spring-type filter device 3, the piping is roughly divided into a pipe 36 for raw liquid and a pipe 37 for filtrate. The pipe 36 for raw liquid is also received at the front stage of the spring-type filter device 3 and is used to supply raw liquid to the lower space 341 of the spring-type filter device 3. The pipe 36 for raw liquid is configured with a pump 361 and a valve 362 provided in the middle, and the pump can supply raw liquid into the spring-type filter device 3, and the valve 362 can control the opening and closing of the path formed by this pipe. The pump 361 is connected to the cassette gas cylinder generator 2, and can send the raw liquid to the spring-type filter device 3. The pipe 36 for raw liquid is further connected to a branch pipe 363 for waste liquid, which allows the used filter aid to be discharged. The branch pipe 363 for waste liquid is also connected to a valve 364, which allows the path to be opened and closed.

As shown in the figure, the filtrate pipe 37 is a pipe used to send the filtrate filtered by the spring filter device 3 to the outside. A valve 371 is arranged in the filtrate pipe 37, and the opening and closing of this path can be controlled. As described above, the filtrate pipe 37 is connected to a circulation pipe 372 that branches off to form a circulation path, and is connected to the raw liquid pipe 36 via a valve 373, which is equipped with a filter aid tank 374, a pump 375, and a valve 376. This allows the raw liquid pipe 36 and the filtrate pipe 37 to circulate. As is clear from this description, the filter aid tank 374 contains a filter aid 35 dispersed together with water, and by circulating the water in which the filter aid 35 is dispersed through this circulation path, the filter aid 35 gradually builds up around the spring filter 31, forming a filter.

In addition, in the present device 1, the raw liquid pipe 36 and the filtrate pipe 37 are preferably made of a hard material such as metal or resin in part, but are also preferably made of a flexible pipe in part, from the viewpoint of being able to withstand the negative pressure of suction, etc., although this is not limited thereto. In actual disasters, etc., there are various containers and locations for containing the raw liquid to be treated, and it is very effective if the pipes can be moved appropriately according to the shape and location of the container, and if they are covered with a hard material, they can be protected even if they are subjected to external impact. In addition, when seawater is used as raw water, water can be easily obtained by immersing the tip of the raw liquid pipe 36 (or the above-mentioned pipe T1 via the hair collection device 5 connected to it) in the sea without pumping out seawater. On the other hand, even if they are flexible, it is preferable that they are made of strength and flexibility by weaving metal or the like. In this way, they are less likely to be crushed even when pressure is applied by suction. As for the configuration, specifically, since there is little need to change the position of the circulation portion, it is preferably made of a hard material such as resin or metal, while the portion at the tip (the inlet or outlet side) is preferably made of a flexible material. As a tube that can withstand the load of suction while being flexible, it is preferable to use, for example, a metal flexible hose, but is not limited to this.

It is also preferable to have a mesh filter attached near the suction port of the concentrate pipe 36 on the suction side. This makes it possible to remove large impurities such as stones, branches, and fallen leaves that have passed through the hair collection device 5 in advance.

It is also preferable to provide a hair collection device (hair catcher) 5 near the suction port of the concentrate pipe 36 on the suction side or in front of it. By providing the hair collection device 5, it becomes possible to remove large impurities such as stones, branches, and fallen leaves in advance, just like the above-mentioned filter. The structure of the hair collection device 5 can be a hair collection device (hair catcher) that is generally available on the market.

As described above, the present device 1 is also equipped with the pump 361. The pump 361 is a device used to send fluid in one direction, specifically to send the raw liquid to be treated, and in the present device 1, it is capable of forming a flow of air or liquid from the outside to the lower space 341, from the lower space 341 to the upper space 342, and from the upper space 342 to the outside.

In addition, in this device 1, the pump 361 is connected to the cassette gas cylinder generator 2 as described above, and is driven by the power generated by the cassette gas cylinder generator 2. The pump 361 may be located on the inlet side of the lower space, or on the outlet side of the upper space. When located on the inlet side of the lower space, the flow is in the direction of supplying fluid to the lower space, and when located on the outlet side of the upper space, the flow is in the direction of sucking fluid from the upper space.

The configuration of the pump used in this device 1 is not limited as long as it has the above functions, and may be a non-positive displacement pump that rotates blades in the space inside the device to pump fluid, or a positive displacement pump that rotates multiple meshed gears to pump fluid, or even a reciprocating vibration pump that uses the reciprocating vibration of a piston to pump fluid.

As described above, during filtration, the filter aid 35 for the spring filter is placed around the spring filter 31 in the spring filter device 3. More specifically, during filtration, the filter aid 35 is layered around the spring filter 31 by the force of the spring filter 31 pumping the liquid from the lower space 341 side to the upper space 342 side. This allows the filter aid 35 to function as a filter layer for removing insoluble matter.

In addition, in this method, the form of the filter aid 35 is preferably, but not limited to, a powder. By using a powder filter aid, it becomes easier to disperse in liquid, and it can be stably arranged by layering around the spring-type filter 31, so-called precoat effect. The size of the filter aid powder is not particularly limited, but it is preferable that the average particle size is, for example, in the range of 5 μm to 500 μm, and more preferably, the average particle size is in the range of 10 μm to 100 μm.

The composition of the filter aid 35 is not limited as long as it can perform the above-mentioned functions, and may be, for example, an inorganic substance such as diatomaceous earth, activated carbon, or zeolite, or an organic substance such as polyolefins including polyethylene, polypropylene, and the like and their derivatives, halogenated polyolefins including polyvinyl chloride, polyvinyl acetate, polyethylene tetrafluoroethylene, and the like and their derivatives, halogenated olefin copolymers including ethylene-vinyl alcohol, and the like and their derivatives, cellulose, and the like, and cellulose derivatives having a cellulose skeleton, etc.

In addition, in the present device 1, it is preferable that the filter aid is provided with a filter aid container that contains the filter aid. Although the filter aid can be considered a consumable item, it can be reused after cleaning, and the amount of the filter aid used as a consumable item is not so large, and it has the advantage that a much smaller amount is required than in the filters of the prior art. The method of actually using the filter aid and its form will become clear from the description below.

In addition, the device 1 is equipped with a reverse osmosis membrane device 4 at the rear of the filtration device 3. The reverse osmosis membrane device 4 is equipped with a reverse osmosis membrane, and impurities present in the filtrate can be removed by the action of this reverse osmosis membrane. That is, while physical filtration is performed by the filtration device at the front stage, it is possible to filter out minute impurities or dissolved impurities present in the water by the reverse osmosis membrane device 4 at the rear stage. In particular, when seawater is used as raw water, it is possible to remove organic matter and ions that are present in the seawater and cannot be completely removed by the filtration device 3. Here, the "reverse osmosis membrane" is also called an RO (Reverse Osmosis) membrane, and is formed with many holes of about several nanometers, and the fluid is purified by capturing organic matter and the like through these holes. Specifically, by applying pressure to the filtrate side containing impurities, it is possible to allow only water to pass through to the other side of the reverse osmosis membrane, and this water can be used for domestic water, etc. This reverse osmosis membrane device is essential for drinking water and other water that people will ingest, but can be omitted for toilets and other uses where the inclusion of unnecessary ions from a hygienic standpoint is not an issue.

In addition, like the filtration device 3, the reverse osmosis membrane device 4 is preferably equipped with a pump for pumping fluid into the reverse osmosis membrane device 4 at high pressure. The type of pump is the same as the pump in the filtration device.

As described above, this device 1 makes it possible to provide an emergency filtration device that can be stored stably for long periods of time more easily and requires fewer consumables.

(Filtration method)
Here, the details of the filtration method (hereinafter referred to as "this method") will be explained step by step. First, in this method, a case where the raw liquid is pumped from a water source S as preparation will be explained. Note that, in this method, the water source S is used as an example from the viewpoint of ease of explanation, but the raw liquid may be pumped from a container containing the raw liquid. Note that the water source S can be, for example, a pond, a river, the sea, etc., but is not limited to these.

First, in this method, filter aid 35 is placed around spring filter 31. Specifically, filter aid tank 374 is filled with relatively clean water, and filter aid 35 is dispersed in it to create a precoat liquid. Then, pump 375 is driven to introduce precoat liquid from filter aid tank 374 into lower space 341, and water discharged from upper space 342 is returned to filter aid tank 374. By repeating this operation, filter aid gradually accumulates around spring filter 31 and forms a filter layer.

Next, after sufficient pre-coating has been performed, the raw liquid is pumped up from the water source S via the pipe T1 using a pump, and while fallen leaves and hair are removed using the hair collection device 5, the assembled raw liquid is supplied to the lower space 341 of the spring-type filter device 3 and filtered. The filtered water is discharged from the filtrate pipe 37. The filtrate discharged from this filtrate pipe 37 has had impurities removed to the extent that it can be used as water for daily life.

As a result, minute impurities present in the raw liquid are captured in the gaps of the filter aid and cannot move into the internal space (upper space) 342 of the spring-shaped filter 31. As a result, the raw liquid is filtered by the spring-shaped filter 31.

When filtration is complete, the pump can be stopped to end the process. Completion of filtration can be when there is no more raw liquid, or when the pressure of the fluid in the housing reaches a predetermined pressure or higher. When the pressure reaches a predetermined pressure or higher, this is because the gaps between the filter aid particles have begun to fill with the trapped impurities, so it is preferable to temporarily end filtration and pre-coat again with filter aid from which the impurities have been removed. In this case, it is preferable to leave a small amount of filtrate for pre-coating in the next process.

Furthermore, when this method is completed, there may be cases where filter aid remains attached around the spring filter 31. For this reason, it is preferable to carry out a step of reversing the flow of the pump to remove the filter aid attached around the spring filter 31. Specifically, the valve 364 can be opened and the filter aid can be discharged from the waste liquid branch pipe 363. In this way, the spring filter 31 can be kept clean. Since the removed filter aid will accumulate under the lower space 341, a decrease in work efficiency due to the accumulation of filter aid can be prevented by leaving the lower part of the housing open.

In this method, the filtrate filtered by the filtration device is further filtered by a reverse osmosis membrane device installed downstream. Specifically, the filtrate is sent into the reverse osmosis membrane device using a pump or the like, and purified water that has permeated the reverse osmosis membrane is extracted. Note that the discharged filtrate other than purified water can be discarded as wastewater, but as mentioned above, it can also be used as is for daily life purposes other than drinking water where hygiene is not a major concern.

As described above, this device makes it possible to remove insoluble matter of a certain size or larger by combining the spring filter 31 and the filter aid 35 placed around it. In addition, by using a reverse osmosis membrane device, it is possible to remove insoluble matter of a certain size or smaller, such as organic matter and ions, to obtain water suitable for drinking. This device is particularly effective because it can replace seawater with purified water.

In addition, because this device 1 uses a generator that uses a gas cartridge, there is less risk of deterioration or failure even if the gas remains inside the device, unlike gasoline, etc. Also, unlike batteries, it can be stored in large quantities and stably, and there is less risk of leakage. Furthermore, because a spring-type filter device is used, the effort required for filter replacement is extremely small compared to general filter devices. Even if it is necessary, it is a filtration aid, and unlike normal filters, not only can filtration be performed with a very small amount, but the effort required for filter replacement is very small. In other words, it is possible to provide an emergency filtration device that can be stored stably for long periods of time more easily and requires fewer consumables.

The present invention has the potential for use as a filtration device in industrial settings. In particular, it is a simple system that can be used in times of disaster, and there is little risk of deterioration even after long-term storage, making maintenance extremely easy.

Claims (2)

A cassette gas generator,
a spring-type filter device driven by the power generated by the cassette gas generator;
A hair collection device provided in front of the spring-type filter device;
A filtration device comprising:
The spring-loaded filter device is
A spring-loaded filter,
A support member for supporting the spring-type filter;
a housing having an internal space for accommodating the spring-type filter and the support member;
and a pump for delivering the raw liquid to be treated to the internal space of the housing,
The pump is driven by the cassette gas generator,
The internal space of the housing is divided into a lower space and an upper space by the support member,
A concentrate pipe is connected to the lower space,
A filtrate pipe is connected to the upper space,
The raw liquid pipe and the filtrate pipe are connected to form a circulation path via a filter aid tank,
A waste liquid branch pipe for discharging the filter aid is connected to the raw liquid pipe,
Furthermore, the tip of the concentrate tube is made of a flexible material. 2. The filtration device according to claim 1, further comprising a reverse osmosis membrane device provided downstream of the spring type filter device.