JP2005048509A - Storage infiltration facility for rainwater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a storage or infiltration facility for rainwater or the like in which rainwater having a comparatively clean water quality is infiltrated to an underground section and an underground pollution can be prevented and comparatively clean rainwater can be stored and utilized. <P>SOLUTION: In the storage or infiltration facility 1 for rainwater composed of an infiltration tank 2 and a storage tank 3 connected through a flow-path changeover means 4, flowing-in initial rainwater is introduced to the tank 3, and a flow path for rainwater is changed over by a means 4 and subsequent rainwater is introduced into the tank 2 when the quantity of a storage reaches a fixed quantity. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a rainwater storage and penetration facility.

Conventionally, as a facility for storing and infiltrating rainwater, a facility for connecting the storage facility and the infiltration facility and allowing the rainwater to infiltrate underground when inflow exceeding the storage amount is known (for example, see Patent Document 1). .
Further, a pumping device such as a pump is provided, and the stored rainwater is used for plant irrigation, fire prevention, toilet water, washing water, etc. (water utilization) (for example, Patent Document 1 or Patent Document 2). reference.).

On the other hand, at the beginning of the rain, rainwater takes in airborne suspended solids (dust, dust, NOx, SOx, etc.) into the rainwater during the fall, and further falls on the surface of the roof, road, etc. It flows while washing away the accumulated foreign matter. Such rainwater is called initial rainwater, and the water quality is very bad. However, rainwater after a certain amount of rain falls in a relatively clean atmosphere and flows on a relatively clean surface, so the water quality is good.
JP-A-9-41470 JP-A-11-71789

  As shown in Patent Document 1, in a facility that connects a storage facility and an infiltration facility and infiltrates the rainwater into the basement in the case of an inflow exceeding the storage amount, the initial rainwater with poor water quality collected in a wide area is separated. There is a risk that it will permeate underground without contaminating it and contaminate the underground. Such initial rainwater with poor water quality needs to be trapped for treatment or flow to a facility that can be treated, such as a sewage treatment facility.

  In addition, as shown in Patent Document 1 or Patent Document 2, when rainwater stored by using a pumping device such as a pump is used for water utilization, the water quality is poor and the range of use of the stored water is also limited. There is a problem that is done.

  In the present invention, the poor water quality means that the COD exceeds 30 ppm. For example, for water utilization, if the COD is 20 ppm or less, it can be used for toilet water or the like (related to miscellaneous water supply). Water quality standards (Ministry of Economy, Trade and Industry)) If it is 10 ppm (standard for tap water) or less, it can be applied to toilet seats for hot water washing, and the range of use of stored rainwater is further expanded. In addition, relatively clean rainwater refers to rainwater that can be regarded as having no or little initial rainwater with poor water quality.

  The present invention solves the problems of the conventional rainwater storage and infiltration facilities, can prevent the underground pollution by infiltrating rainwater with relatively clean water quality into the underground, and can store and use relatively clean rainwater. To provide a storage and infiltration facility.

  In order to achieve the above object, a rainwater storage and infiltration facility according to claim 1 of the present invention (Invention 1) is a rainwater storage and infiltration facility comprising an infiltration tank and a storage tank connected via a flow path switching means. Then, the inflowing initial rainwater is guided to the storage tank, and when the storage amount reaches a predetermined amount, the rainwater flow path is switched by the flow path switching means, and the subsequent rainwater is guided to the infiltration tank.

  The rainwater storage and infiltration facility according to claim 2 (Invention 2) is a rainwater storage and infiltration facility in which an infiltration tank and a plurality of storage tanks are connected to each other via a flow path switching means, and the initial rainwater that has flowed in To the first storage tank, and when the storage amount of the first storage tank reaches a predetermined amount, the flow path switching means switches the rainwater flow path and guides the subsequent rainwater to the second storage tank. When the storage amount of the storage tank reaches a predetermined amount, the storage tank is guided to the permeation tank.

  According to a third aspect of the present invention (invention 3), the flow path switching means is a bottomed tubular body, and an inflow water passage and a plurality of distribution water passages are provided on a side surface of the tubular body. The height of the bottom of the inflow water channel is lower and different from each other, the upper distribution water channel is connected to the infiltration tank, and the lower distribution water channel is connected to the storage tank. This is a rainwater storage and penetration facility.

  The rainwater storage and penetration facility of the present invention is, for example, as an example, a storage tank in which the ground is opened and dug down, and the bottom surface and peripheral side surface of the excavation hole are lined with a material having a water shielding property or a synthetic resin, concrete, or the like And a permeation tank in which a bottom surface and a peripheral side surface of a similar excavation hole are lined with a material such as a water-permeable sheet or water-permeable concrete.

  Or, the ground is opened and dug down to form a tank space, and a plurality of filling members are arranged in the vertical and horizontal directions in the space, and this lateral periphery is covered with a water-impervious sheet or the like as a storage tank, or a water-permeable sheet The permeation tank may be covered with a so-called permeation tank.

  The storage tank and the permeation tank are independent tanks even if the lower tank is a storage tank, the upper peripheral side of the storage tank is a water-permeable material, and the upper part is a permeation tank. It may be a facility arranged in parallel in the horizontal direction.

  The inside of the storage tank and the permeation tank may be an empty space, and a plurality of filling members may be arranged horizontally and vertically in the space inside the tank. By using the filling member, the space of the above-ground part can be effectively utilized. In addition, if a material with a low impurity solute such as plastic is used as the filling member, there is no alkali component solute generated when a concrete filling member is used, so that the quality of the infiltrated rainwater and the rainwater used can be further improved. In addition, the filling member is light and the construction is simple.

  When the filling member is provided with a guiding means for guiding rainwater and sand flowing into the storage tank or infiltration tank in a desired direction by gravity or water flow, the earth and sand contained in the initial rainwater with poor water quality at least at the initial stage of rainfall. Can be collected at a desired location, usually the deepest part of the bath. Therefore, if the tip of the pipe reaches the bottom of the tank and is sucked with a pump, the accumulated sand and the like can be easily removed, and the capacity drop during long-term use can be suppressed. Even in the permeation tank, even if foreign matter such as sand is mixed in, the capacity reduction can be similarly suppressed.

  The rainwater storage and penetration facility may be provided with an inflow port for receiving rainwater drainage in a side gutter of the road, and the storage tank may be provided with a drainage channel connected to the penetration tank. The drainage tank is usually provided with a drain pipe in case there is more rainfall than designed.

  In addition, in the rainwater storage and infiltration facility of the present invention, a manhole for work reaching the U-shaped groove provided at the deepest part of the storage tank is provided for the convenience of cleaning foreign matter, maintenance of the filling member, etc. It may be provided in the vicinity. If necessary, a manhole reaching the bottom surface of the permeation tank may be provided in the vicinity of the permeation tank, or a storage tank manhole and a permeation tank manhole may be used together.

  In the present invention, when the stored rainwater is used, the stored water in the permeation tank or the storage tank may be pumped out by a pump or the like. The pipe may be connected to a faucet as it is, or may be connected to a water pipe of a facility such as a building. The water pipe is not particularly limited as long as it can be used in buildings such as water, middle water, rainwater, sewage, etc., and the facilities to be connected are not limited to buildings, such as road gutters and parking lots. Or a park. The stored rainwater may be divided into snowmelt, water spray, emergency emergency water, etc. depending on the quality of the water.

  In the first aspect of the invention, initial rainwater with relatively dirty water quality that flows within a certain time after rain is stored in a storage tank, and then rainwater with relatively clean water quality is guided to an infiltration tank and temporarily stored. Infiltrate this underground. If necessary, the rainwater stored in the infiltration tank may be pumped up to use water.

  The rainwater stored in the storage tank is dirty rainwater within a certain time from the rain or less than a certain amount of water. The amount of water to be stored in the storage tank is determined by the quality of rainwater to be permeated. That is, after confirming that the quality of the initial rainwater guided to the storage tank has become equal to or lower than the predetermined water quality, the rainwater is guided to the infiltration tank by the flow path switching means. However, it is often not installed to continuously measure the quality of inflowing rainwater because the continuous measurement apparatus becomes expensive in terms of equipment.

  In that case, when rainwater of a predetermined amount of water is stored in the storage tank, a method of switching the flow path may be taken on the assumption that the water quality is clean. Of course, in this case, preliminarily test the relationship between the amount of stored water and the quality of influent rainwater, accumulate statistical data, analyze this, calculate the amount of stored water to switch the flow path, and set the capacity of the storage tank It is necessary to keep it.

  In the second aspect of the present invention, initial rainwater of relatively dirty water quality that flows in the side groove within a certain time after a plurality of rainfalls is stored in the first storage tank among the plurality of storage tanks, and then the water quality is relatively low. The cleaned rainwater is stored in the second storage tank, and the rainwater whose water quality is relatively clean is guided to the infiltration tank and temporarily stored, and this is infiltrated into the underground.

  Rainwater stored in the second storage tank is rainwater with relatively good water quality. Therefore, when it is desired to use the water quality strictly classified, for example, when the stored rainwater has a COD of about 20 ppm, it is certain that it should be used only for miscellaneous water such as toilet water or watering. Can be used. If necessary, the rainwater stored in the infiltration tank may be pumped up to use water. Since the temporarily stored rainwater can be expected to be rainwater having a better water quality than the rainwater stored in the second storage tank, the use is further expanded. The rainwater stored in the first storage tank is pumped up and processed at a public sewage treatment facility or the like.

  The first storage tank, the second storage tank, and the permeation tank may be arranged vertically, horizontally, or combined.

  The capacity | capacitance of a 1st storage tank needs the capacity | capacitance which can store the initial rain water with bad water quality reliably. The capacity | capacitance of a 2nd storage tank should just be decided by how much rain water of the water quality is required. That is, when stocking as emergency water in an emergency, there is a possibility that the capacity will be considerably large. Further, since rainwater temporarily stored in the infiltration tank permeates into the underground with time, the capacity is determined by the drainage pipe and the processing capacity of the facility following this storage or infiltration facility. However, when using temporarily stored rainwater, the capacity may be changed as appropriate, and in some cases, further third, fourth,... Storage tanks may be provided.

  The rainwater flow path is switched after confirming that the quality of the initial rainwater is equal to or lower than the predetermined water quality, as in the case of the first aspect.

  The flow path switching means of the invention 3 has a bottomed cylindrical shape, and is provided with an inflow pipe and a plurality of distribution pipes on the side of the cylindrical body, and the bottom surface height of the distribution pipe is higher than the bottom surface height of the inflow pipe. The lower distribution pipe is connected to the permeation tank, and the lower distribution pipe is connected to the storage tank.

  The cylindrical main body of the flow path switching means is not particularly limited as long as it has excellent corrosion resistance and pressure resistance. For example, plastics such as PVC (vinyl chloride resin); structures such as RC (reinforced concrete) Articles: Composite resins such as FRP (fiber reinforced resin) and FRPM (resin concrete), or molded products of metals such as SUS (stainless steel), anticorrosive iron, and aluminum.

  When the storage tank is located below and the top permeation tank is located above, the initial rainwater after the rain passes through the lower distribution pipe if the height of the bottom of the upper distribution pipe is set to the height when the storage tank is full. When the storage tank is full when it is guided to the storage tank and the quality of the rainwater is clean, the water level in the cylindrical body coincides with the bottom of the upper distribution pipe. It is led to the seepage tank through the distribution pipe.

  In addition, in the case where they are stacked in the above-described vertical direction, the storage tank and the permeation tank are integrated. The boundary line between the tanks may be provided with a partition plate for separating the tanks from each other so that rainwater flowing into the tanks does not mix.

  When the permeation tank and the storage tank independent from each other are arranged in parallel in the horizontal direction and the water level of each tank is not constant, the flow path switching may be performed by a valve. That is, for example, the initial rainwater may be guided to a storage tank equipped with a water level gauge, the water level detected, and when the water level reaches a predetermined level, the valve is switched to guide the rainwater to the infiltration tank. Therefore, in this case, since the flow path of the rainwater is switched regardless of the water level of each tank, whichever of the storage tank and the permeation tank and the full water level may be higher. In addition, the switching timing may be determined by the accumulated time from the start of rainfall, for example, without depending on the water level gauge. In this case, for example, an automatic valve such as an electromagnetic valve, an electric valve, or an air operated valve may be used as the switching valve, and a power source for operating the automatic valve may be used in combination.

  In this way, the flow path switching means uses the above cylindrical shape when distributing to each tank arranged in the vertical direction, and if distributing to each tank arranged in the horizontal direction, a valve or the like is used. Use it. However, it goes without saying that all the flow path switching means may be valves.

  In invention 1, since the initial rainwater with poor water quality is stored and does not penetrate into the ground, underground pollution can be surely prevented. Furthermore, since relatively clean rainwater not mixed with initial rainwater is temporarily stored in the permeation tank, water can be used by pumping it up.

  In the invention 2, in addition to the effect of the invention 1, a plurality of storage tanks are provided, so that rainwater with good water quality can be selected and stored, and rainwater with good water quality can be stored in each storage tank. The range of water use is expanded by selecting and storing.

  In the invention 3, the flow of rainwater to be distributed by natural flow is switched without using power such as a pump or an automatic valve to separate rainwater that has flowed into the facility, so energy for distribution is unnecessary and simple. In addition, relatively clean rainwater can be easily guided to a storage tank or the like, and since there are no pumps or automatic valves, maintenance is not required, initial equipment costs are easy, and facility maintenance is easy.

  Next, the rainwater storage and penetration facility of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing an example of a rainwater storage and penetration facility 1 in which an infiltration tank 2 and a storage tank 3 are arranged vertically with a partition plate 8 interposed therebetween. The permeation tank 2 and the storage tank 3 are separated by a partition plate and are independent tanks. The permeation tank 2 is disposed above and the storage tank 3 is disposed below. The permeation tank 2 and the storage tank 3 of the present embodiment are filled with a plastic filling member, and a water permeable sheet is provided on the side peripheral surface of the filling member to form the permeation tank 2, and a water shielding sheet is provided. 3.

  The flow path switching means used (see FIG. 5A) is provided with the rainwater inflow pipe 5 and the distribution pipes 61 and 62 on the side surface of the bottomed cylindrical main body 4. The distribution pipe 62 is connected to the permeation tank 2. The infiltration tank 2 is provided with a drain pipe 71 that also serves as a drain pipe for the entire facility at the water level height when the water is full, and the storage tank 3 is provided with a drain pipe 72 at a height near the bottom surface. , Each is provided with a valve, which is normally closed.

  The bottom U-shaped groove of the storage tank 3 is provided with discharge means for removing earth and sand flowing into the tank together with rainwater. Furthermore, the permeation tank 2 may be provided with a pump and a pipe for supplying rainwater with relatively good water quality that is temporarily stored.

  The pipe bottom height of the distribution pipe 62 is an intermediate height between the pipe bottom height of the inflow pipe 5 and the pipe bottom height of the distribution pipe 61. The pipe bottom height of the inflow pipe 5 is higher than the full water level height of the infiltration tank 2, and the pipe bottom height of the distribution pipe 62 is substantially the same as the full water level of the storage tank 3.

  The pipe bottoms of the distribution pipes 61 and 62 may have a slight difference in height, but the relative height relationship should not be reversed. Because the storage tank 3 is independent, if it becomes full, the water level of the cylindrical body 4 of the flow path switching means rises while maintaining the full water state, and the bottom of the upper distribution pipe 62 This is because when the water level rises to the height, the inflowing rainwater automatically flows into the infiltration tank 2 from the pipe 62 accordingly.

  In the early stage of rainfall, the initial rainwater with poor water quality flows into the storage tank 3 through the distribution pipe 61 and is stored in the storage tank 3. When the inflow of rainwater proceeds and the storage tank 3 reaches a predetermined amount of stored water, the inflow of rainwater into the storage tank 3 stops, the water level in the cylindrical body 4 of the inflow switching means rises, and the bottom of the distribution pipe 62 rises. Is the same. Then, the rainwater after this flows into the infiltration tank 2 through the distribution pipe 62 and infiltrates the rainwater into the ground while temporarily filling it. Rainwater that flows in excess of the capacity of the infiltration tank is discharged through the drain pipe 71 of the facility with the valve opened.

  The initial rainwater with poor water quality stored in the storage tank 3 is transferred to a sewage treatment facility or the like by opening a valve after a certain period of time, and purified there.

  FIG. 2 is a plan view showing an example of the rainwater storage and penetration facility 10 in which the independent penetration tank 20 and the storage tank 30 are arranged in the horizontal direction.

  The structure of each of the permeation tank 20, the storage tank 30, or the flow path switching unit is the same as that of the first embodiment, and the operation thereof is also the same. By arranging each tank 20 and 30 horizontally, an independent permeation tank and a storage tank can be provided relatively easily, and the construction becomes easy.

  FIG. 3 is a cross-sectional view showing an example of an embodiment of a rainwater storage and penetration facility 100 in which two storage tanks 31 and 32 independent of each other are arranged in the vertical direction. Although the description of the permeation tank 2 is omitted in this example, the permeation tank 2 may be disposed further above the storage tanks 31 and 32 or may be disposed in the horizontal direction.

  The flow path switching means used (see FIG. 5B) is provided with a rainwater inflow pipe 5 and distribution pipes 61, 62, 63 on the side surface of the bottomed cylindrical main body 4, and the distribution pipe 61 is stored. In the tank 31, the distribution pipe 62 is connected to the storage tank 32, and the distribution pipe 63 is connected to the infiltration tank 2. In this figure, since the description of the permeation tank 2 is omitted, the distribution pipe 63 is also omitted.

  At the bottom of the infiltration tank 2 or the storage tanks 31 and 32, earth and sand that flows into the tank together with rainwater is deposited, and therefore a discharge means for removing the sediment is provided. Further, the permeation tank 2 is provided with a pump and a pipe for supplying rainwater having a relatively high quality which is temporarily stored.

  The pipe bottom height of the distribution pipe 62 is an intermediate height between the pipe bottom height of the distribution pipe 61 and the pipe bottom height of the distribution pipe 63, and the pipe bottom height of the distribution pipe 63 is substantially equal to the pipe bottom height of the inflow pipe 5. To be matched. The pipe bottom height of the inflow pipe 5 is higher than the full water level of the infiltration tank 2, the pipe bottom height of the distribution pipe 62 is substantially the same as the full water level of the storage tank 31, and the pipe bottom of the distribution pipe 63 is The height is substantially the same as the water level when the storage tank 32 is full.

  In the early stage of rainfall, the initial rainwater with poor water quality flows into the first storage tank 31 through the distribution pipe 61 and is stored in the first storage tank 31. When the inflow of rainwater proceeds and the first storage tank 31 reaches a predetermined storage amount, the inflow of rainwater into the first storage tank 31 stops, the water level in the cylindrical body 4 of the inflow switching means rises, This is the same as the height of the bottom surface of the distribution pipe 62. Then, the rainwater after this flows into the 2nd storage tank 32 through the distribution pipe 62, and is stored. When the second storage tank 32 becomes full, the water level in the cylindrical body 4 of the inflow switching means rises and becomes the same as the bottom surface height of the distribution pipe 63. Then, the rainwater thereafter flows into the infiltration tank 2 through the distribution pipe 63, and infiltrates the rainwater into the ground while temporarily satisfying this. Rainwater that flows in excess of the capacity of the infiltration tank 2 is discharged through the drain pipe 71 of the facility.

  Therefore, since the rainwater stored in the second storage tank 32 is rainwater having a relatively good water quality, the range of water use is widened. In addition, initial rainwater with poor water quality stored in the first storage tank is opened after a certain period of time and transferred to a sewage treatment facility or the like for purification.

  FIG. 4 is a cross-sectional view showing an example of an embodiment of a rainwater storage and penetration facility 1000 configured by dividing the top and bottom of one tank into a permeation tank 2000 and a storage tank 3000. In this facility 1000, a tank space is formed by opening up the ground and digging up, a plurality of filling members are arranged in the vertical direction and the horizontal direction, and the lateral periphery is covered with a water-impervious sheet or the like, and the storage tank 3000 And osmotic tank 2000 covered with a water-permeable sheet or the like. In other words, the fourth embodiment may be considered to be integrated with the first embodiment without the partition plate 8 between the storage tank 3 and the permeation tank 2.

  An automatic valve may be used as the flow path switching means for all the first to fourth embodiments described above. By using an automatic valve, etc., it is possible to reliably guide the initial rainwater with poor water quality to the storage tank, prevent underground pollution, and to store rainwater with a relatively good quality only when necessary. This has the advantage of expanding the water utilization range.

It is sectional drawing which shows an example of the rainwater storage penetration facility by which the penetration tank and the storage tank were arrange | positioned perpendicularly across the partition plate. It is a top view which shows an example of the storage penetration facility of the rainwater by which the independent penetration tank and the storage tank are arrange | positioned at the horizontal direction. It is an example of a rainwater storage and penetration facility in which two storage tanks independent of each other are arranged in the vertical direction, and is a cross-sectional view in which the description of the penetration tank is omitted. It is sectional drawing which shows an example of the rainwater storage penetration facility 1 comprised by dividing the upper and lower sides of one tank into the permeation tank and the storage tank. (A) is sectional drawing of an example of the flow-path switching means with two distribution pipes, (b) is sectional drawing of an example of the flow-path switching means with three distribution pipes.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 10, 100, 1000 Rainwater storage penetration facility 2, 20, 2000 Permeation tank 3, 30, 3000 Storage tank 31 1st storage tank 32 2nd storage tank 4 Cylindrical main body of flow-path switching means 5 Inflow pipe 61, 62, 63 Minute pipe 71 Drain pipe of permeation tank right equipment 72 Drain pipe of storage tank 8 Partition plate

Claims (3)

A rainwater storage and infiltration facility comprising an infiltration tank and a storage tank connected via a flow path switching means,
Introduce the initial rainwater into the storage tank,
A rainwater storage and infiltration facility characterized in that, when the storage amount reaches a predetermined amount, the flow path of the rainwater is switched by the flow path switching means and the subsequent rainwater is guided to the infiltration tank. A rainwater storage and penetration facility in which an infiltration tank and a plurality of storage tanks are connected to each other via a flow path switching means,
The initial rainwater that flowed in is guided to the first storage tank,
When the storage amount of the first storage tank reaches a predetermined amount, the flow path switching means switches the rainwater flow path and guides the subsequent rainwater to the second storage tank,
A rainwater storage and penetration facility characterized in that when the storage amount of the second storage tank reaches a predetermined amount, the second storage tank leads to the penetration tank. The flow path switching means is a bottomed cylindrical body;
An inflow water channel and a plurality of distribution water channels are provided on the side surface of the cylindrical body,
The bottom height of the distribution channel is lower than the bottom height of the inflow channel and is different from each other.
The upper distribution channel is connected to the infiltration tank,
The rainwater storage and penetration facility according to claim 1, wherein a lower distribution water channel is connected to the storage tank.

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