JPH09184172A - Rainwater filtering device for river - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a river from being polluted by inflow of rainwater by utilizing a limited space, and to make effective utilization possible for rainwater. SOLUTION: Permeable bases 2 for letting rainwater flow down from an upper river are formed at both banks on the right and the left of the upper river 1 constituting an artificial hydrophilic river. A plurality of permeable filter layers 3 are formed below the upper river 1 and the permeable bases 2. A reservoir 4 for filtrate is formed at the downside of the permeable filter layers 3. As rainwater falling onto areas around the upper river 1 flows down, without flowing into the upper river 1, through the permeable bases 2, the river can be prevented from being polluted by rainwater. The rainwater flowing toward the downside is reserved in the reservoir 4, being filtered by the filter layers 3. As the filtrate, instead of city water, is allowed to flow into the upper river, maintenance cost for the artificial hydrophilic river can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rainwater filtration device for a river, which prevents the infiltration of polluted rainwater into a river as it is and filters the polluted rainwater to effectively utilize the rainwater.

[0002]

2. Description of the Related Art Conventionally, in order to effectively use water resources,
The rainwater collected from the roof of the building is filtered in a rainwater filtration facility installed on the building's premises, and the filtered water is used as tap water used for washing cars, toilet water, etc. Is partly implemented in public facilities.

That is, a method has been proposed in which in the city, the water that finally flows into the sewage from the roof of the building is effectively used as gray water without directly flowing into the sewage. On the other hand, in order to become familiar with the water of rivers as nature, artificial hydrophilic rivers have been set up in parks and promenades, etc. An environment has been put in place that allows people to become familiar with the water in the river.

[0004]

By the way, in rivers having high hydrophilicity as described above, particularly in hydrophilic rivers in which children can play in water, clear water needs to flow, but When it falls, the rain that has fallen around the hydrophilic river flows into the hydrophilic river, which is likely to be at a lower place than the surrounding ground, with the surrounding dirt and soil, etc. The result was polluted water.

In order to prevent the hydrophilic river from being polluted by rainwater, it is conceivable to provide drainage facilities along the river. However, when the drainage facilities are provided, the rainwater eventually flows into the sewage. As a result, rainwater cannot be effectively used. On the other hand, in artificial hydrophilic rivers, tap water needs to be used when clear water cannot be obtained from surrounding rivers or springs. Currently, tap water is used in many hydrophilic rivers. ing.

Therefore, in an artificial hydrophilic river,
There was a problem that running costs were always required and tap water was consumed due to hydrophilic rivers.
If you circulate a portion of the water using a circulation filtration device and discharge it into a hydrophilic river, you can reduce the amount of tap water used, but it is still necessary to replenish the water with tap water. However, there is no substitute for the running cost of using the circulation filtration device. Also, a site for installing a circulation filtration device or the like is required.

That is, in order to prevent pollution due to rainwater in a hydrophilic river, it is necessary to drain the rainwater that has fallen around the hydrophilic river before it flows into the hydrophilic river. There is a contradiction that tap water is being used to flush water to. In addition, it is conceivable to install rainwater filtration facilities as shown in the above conventional example around the hydrophilic river and use rainwater instead of tap water, but unlike the roof of a building, rainwater from around a long river In addition to the difficulty of collecting water, a large site was required for the rainwater filtration facility and the storage of filtered rainwater, which made installation difficult within the limited land of the city.

The present invention has been made in view of the above circumstances, and it is possible to prevent pollution of a river due to inflow of rainwater in a limited space and to effectively use the rainwater. The purpose is to provide a device.

[0009]

A rainwater filter for a river according to claim 1 of the present invention is provided around a river, and
A rainwater permeable part capable of flowing rainwater to the lower side of the river, a filtration layer provided under the river and filtering water flowing down from the rainwater permeable part, and a filtration layer provided under the filtration layer. In addition, a water tank for storing the rainwater filtered by flowing down the filter layer is provided as a means for solving the above problems.

According to the above construction, rainwater that has fallen around the river and is polluted by dirt, soil, etc. around the river flows down from the rainwater permeation part to the bottom of the river before flowing into the river. It can be prevented from being polluted by polluted rainwater. Further, the rainwater flowing down through the rainwater permeable part flows down to the filter layer below the river, and further flows down the filter layer to reach the water storage tank, and is stored in the water storage tank.

That is, it is possible to collect polluted rainwater, filter it, and store it with almost no running cost due to the flow of rainwater. In addition, the stored rainwater can be used as tap water, and when the above river is an artificial hydrophilic river, it is necessary to use tap water in the hydrophilic river by discharging the filtered rainwater to the river. It can be lost.

Further, since the filter layer and the water storage tank are formed on the lower side of the river, it is not necessary to form the filter layer and the water storage tank on the site other than the river, and even in the place where the filter layer and the water storage tank are not provided. It is possible to install rainwater filtration and storage facilities and to effectively use the site around the river.

The rainwater permeable portion may be any as long as it allows rainwater that has fallen around the river to permeate and flow downward. For example, a well-known permeable roadbed can be used. Also, it is possible to use a member having a strength capable of withstanding the top load and provided with a large number of slits, holes, gaps or the like through which rainwater can flow.

Further, it is preferable that the rainwater permeable portion is arranged along both sides of the river so as to efficiently collect the rainwater that has fallen around the river before it flows into the river. The filter layer is not particularly limited, and a filter layer using various filter materials can be used, but it is preferable that the rainwater is naturally flowed and filtered from the viewpoint of cost and the like. Also, as the filter medium, it is preferable to use sand, pebbles, crushed stone, or the like. A porous material such as charcoal may be used as the filter medium.

If a filter material on the surface of which microorganisms such as algae adheres is used as the filter material, not only can contaminants be filtered, but also organic matter can be decomposed and removed. The above water tank can be stored under a river,
Anything is fine.

Further, the rainwater permeation part, the filtration layer, and the water storage tank may be continuously provided over a predetermined range of the river, or may be intermittently provided. Although it may be provided only in a part, it is preferable that the rainwater permeable part is continuously provided in a part where rainwater may flow into the river. In addition, in the above-mentioned configuration, expressions such as “below”, “below”, “below”, etc. are used, but this does not mean “below” the river, but “just below” the river.

In the rainwater filter for a river according to a second aspect of the present invention, the means for solving the above-mentioned problems is that the rainwater stored in the water tank is discharged to the river. According to the above configuration, in an artificial hydrophilic river, the flow of water in the river can be reproduced by the water stored in the water tank with almost no use of tap water, thus reducing the running cost of the artificial hydrophilic river. In addition, natural rainwater rather than tap water can be made to flow into the artificial hydrophilic river in the state where the pollution is prevented as described above, and a more natural hydrophilic river can be created. When the water in the reservoir is discharged into the river, it is necessary to pump up the water in the reservoir with a pump or the like.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION A river rainwater filtration apparatus according to an embodiment of the present invention will be described below with reference to the drawings. The river rainwater filtration device of this example uses the present invention for an artificial hydrophilic river. FIG. 1 shows a vertical cross section of an artificial hydrophilic river provided with a rainwater filtration system for a river of this example.

As shown in FIG. 1, a rainwater filtering apparatus for a river is a permeable roadbed (rainwater permeable section) 2 arranged along the upper river 1 on both left and right banks of the upper river 1 which is an artificial hydrophilic river. 2, a water-permeable filtration layer 3 provided below the upper river 1 and the left and right water-permeable roadbeds 2, 2 and for filtering rainwater flowing from the water-permeable roadbeds 2, 2, and the water-permeable filtration layer 3. Seepage water reservoir (water tank) provided under the device 3
4 is provided.

In the upper river 1, the side walls 1a, 1a and the river bed 1b are made of concrete having a relatively low water permeability. In addition, the side walls 1a, 1a are sloped with a gentle slope in order to increase the hydrophilicity of the upper river 1 (so that a person can easily approach water). Then, the left and right side walls 1a,
The inner side edge portions of the water permeable roadbeds 2 and 2 are joined to the outer side edge portions of 1a, respectively.

The water-permeable roadbeds 2 and 2 are
Before the rainwater flowing into the upper river 1 flows into the upper river 1, it is made to flow down to the water permeable filter layer 3 and has a large number of slits or through holes penetrating from the upper surface to the lower surface, and it is suitable for the overload. It has the strength to withstand.

The water-permeable filtration layer 3 is formed by stacking a plurality of types of filter media in a plurality of layers, and in this example, the water-permeable filtration layer immediately below the upper river 1 and the water-permeable roadbeds 2 and 2. First layer 3 made of sand in order from the top of layer 3
a, a second layer 3b made of charcoal, a third layer 3c made of sand, a fourth layer 3d made of pebbles, a fifth layer 3e made of crushed stone, and a sixth layer 3f made of water-permeable concrete having high water permeability. Has become.

Each of these layers has a function of removing contaminants, and in the second layer 3b made of charcoal, porous charcoal is used to adsorb extremely fine substances or substances in a substantially dissolved state by the porous charcoal. Etc. can be removed. If organisms such as microorganisms and algae adhere to the surface of pebbles and crushed stones, organic matter dissolved in rainwater by the organisms can be removed.

Further, the water-permeable concrete of the sixth layer 3f acts as a filter medium and supports each layer on the sixth layer 3f above the seepage water storage pond 4, such as sand,
Charcoal, pebbles, crushed stone, etc. are prevented from flowing into the seepage water reservoir 4. The permeated water reservoir 4 is a space surrounded by a bottom plate 4a made of concrete having low water permeability and left and right side plates 4b, 4b, and can store rainwater that has passed through the water permeable filter layer 3. is there.

The side plates 4b, 4b of the seepage water reservoir 4 are also provided.
Is configured to extend from the bottom of the seepage water storage reservoir 4 to the top surface of the ground, and constitutes the side wall of the rainwater filtration device including the water permeable subgrades 2, 2, the filtration layer 3, and the seepage water storage reservoir 4. ing. That is, the side plates 4b, 4 of the permeable reservoir 4
The uppermost part of the groove-shaped structure composed of b and the bottom plate 4a is the upper river 1, and the upper part below the upper river 1 is the filtration layer 3,
The lower part is the seepage water reservoir 4.

The outer side edges of the water-permeable roadbeds 2, 2 are joined to the inner surfaces of the side plates 4b, 4b. Further, the seepage water reservoir 4 is continuously arranged below the upper river 1 along the upper river 1, and the water of the seepage water reservoir 4 constitutes the lower river 5. In the rainwater filter device, rivers are arranged in two stages, upper and lower.

However, the lower river 5 is just the water stored in the seepage water reservoir 4, and it is not necessary to flow from the upper river 1 to the downstream. When the water in the seepage water storage reservoir 4 is discharged from the upper side of the upper river 1 by a pump as described below, the bottom plate 4a of the seepage water storage reservoir 4 is used.
It is also possible to provide a water gradient that decreases from below the upper river 1 to above the upper river 1 so that the water in the seepage water reservoir 4 can be easily collected on the upper river 1 side.

In this example, the water in the seepage water reservoir 4 is pumped up and discharged from the upper end of the upper river 1 as described above, so that the upper river 1 is an artificial hydrophilic river. Creates a stream of water. In addition, on the downstream side of the upper river 1, a drainage port penetrating the permeable filtration layer 3 is provided in the river bed at the downstream end of the upper river 1, or at the downstream end of the upper river 1, The water flowing through 1 overflows the permeable roadbeds on both banks of the upper river 1, and the water flowing through the upper river 1 is returned to the permeated water reservoir 4 through the permeable filter layer 3, The rainwater may be circulated and used.

The river rainwater filtering device having the above-described structure can be constructed together with the upper river 1 which is an artificial hydrophilic river. That is, along the portion where the artificial hydrophilic river is provided, a groove (not shown) deeper than the artificial hydrophilic river to be constructed is formed in a state where the left and right side surfaces are soiled. Next, the floor plate 4a and the side plates 4b and 4b of the permeated water reservoir 4 are formed on the bottom and side surfaces of the groove with concrete.

Next, a sixth layer 3f of the water permeable filtration layer 3 made of a water permeable concrete plate is provided so as to divide the water permeable reservoir 4 composed of the floor plate 4a and the side plates 4b, 4b into upper and lower parts. Then, the fifth layer 3e to the first layer 3a of the water permeable filtration layer 3 are formed on the sixth layer 3f, and the river bed 1b and the side walls 1a, 1a of the upper river 1 are provided on the fifth layer 3e and the left and right sides thereof. By providing water-permeable roadbeds 2 and 2 on both sides,
It is possible to form a rainwater filter device for a river in this example.

Next, the operation of the rainwater filtration system for a river having the above-mentioned structure will be described. First, when it rains, the rainwater that has fallen around the upper river 1
Try to flow to the side, but before flowing into the upper river 1,
Rainwater flows down from the permeable roadbeds 2, 2 provided on both the left and right banks of the upper river 1. Therefore, when it rains, it is possible to prevent rainwater that has fallen around the upper river 1 and is polluted with dirt, soil, and the like around the upper river 1 from flowing into the upper river 1. It can prevent itself from becoming polluted.

Further, the rainwater flowing down from the permeable roadbeds 2 and 2 at the time of rainfall is further allowed to naturally flow down the permeable filtration layer 3 and stored in the permeated water reservoir 4 in a state of being purified by filtration. It has become. And the above-mentioned seepage water reservoir 4
Since the water stored in (1) is filtered and purified to some extent, it can be used as the above-mentioned gray water, and the rainwater that has fallen around the upper river 1 can be effectively used.

Further, in this example, the water stored in the seepage water storage reservoir 4 is discharged to the upper river 1 and the upper river 1 is discharged.
Since the water flow is created in the artificial hydrophilic river, it is not necessary to use tap water to create the water flow in the artificial hydrophilic river, and the running cost in the artificial hydrophilic river can be reduced and the water can be saved. In particular, if rainwater is circulated and used as described above, tap water need not be used at all.

If the capacity of the seepage water storage reservoir 4 is large enough, even if the amount of rainfall is extremely large, the rainwater that may flow into the upper river 1 will receive the rainwater.
It is possible to prevent the water from overflowing from the upper river 1 when there is a large amount of rainfall.

If the rainwater flows into the rainwater filter side of the river as described above, the rainwater flows into the rainwater filter side, thereby reducing the amount of rainwater flowing into the sewer side. Therefore, it is possible to prevent backflow of the sewage port and the like when the amount of rainfall temporarily becomes extremely large.

It should be noted that, in a normal river rather than a hydrophilic river, rainwater does not necessarily flow into the river due to a revetment wall or the like, but the filtration layer and the seepage water reservoir are formed below the river. However, by providing a rainwater permeable part around the river, it is possible to install equipment for effectively utilizing rainwater without requiring a site other than the river.

[0037]

According to the rainwater filter for a river according to claim 1 of the present invention, the rainwater that has fallen around the river and is polluted by dirt, soil, etc. around the river is said to be discharged before it flows into the river. It is possible to prevent water from being polluted by polluted rainwater by allowing water to permeate downward from the rainwater permeable part.

The rainwater that has permeated through the rainwater permeable portion flows down to the filter layer below the river, passes through the filter layer, reaches the water tank, and is stored. That is, it is possible to filter and store the polluted rainwater with almost no running cost due to the rainwater flowing down. Moreover, since the stored rainwater can be used as intermediate water, the rainwater can be effectively used.

When the above-mentioned river is an artificial hydrophilic river, it is possible to discharge the stored rainwater into the river and eliminate the need to create a water flow using tap water in the hydrophilic river. The running cost of a hydrophilic river can be reduced. In addition, since the filter layer and the water storage tank are created under the river, it is not necessary to form the filter layer or water storage tank on the site other than the river, and the rainwater can be filtered even in the place where the filter layer or the water storage tank is not installed.・ It is possible to install water storage facilities and effectively use the site around the river.

According to the rainwater filter for a river according to claim 2 of the present invention, in an artificial hydrophilic river, the flow of the river water is reproduced by the water stored in the water storage tank, using almost no tap water. Since it is possible to reduce the running cost of the artificial hydrophilic river, it is possible to flow natural rainwater rather than tap water into the artificial hydrophilic river while preventing pollution as described above. Can be created.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a rainwater filtration device for a river according to an example of an embodiment of the present invention.

[Explanation of symbols]

 1 Upper river (river) 2 Permeable roadbed (rainwater permeable part) 3 Permeable filtration layer (filtration layer) 4 Permeated water reservoir (water tank)

Claims (2)

[Claims] 1. A rainwater permeation part which is provided around a river and which allows rainwater to flow down to the lower side of the river, and a water which is provided below the river and flows down from the rainwater permeation part. A rainwater filtration device for a river, comprising: a filtration layer for filtering; and a water tank provided under the filtration layer and storing rainwater filtered down the filtration layer. 2. The rainwater filtering apparatus according to claim 1, wherein the rainwater stored in the water storage tank is discharged to the river.