JPH0455534A - Drainage manhole - Google Patents

Abstract

PURPOSE:To improve drainage efficiency by providing a catchment section, which receives water only through the upper surface thereof, in the central part of a manhole, disposing a water-permeable cylinder with its lower end connected to a drainage system and arranging a layer of absorbents around the cylinder. CONSTITUTION:At the beginning of rainfall at a golf course, precipitation of highest concentration of agricultural chemicals is absorbed into the soil 20 and decomposed gradually by soil microorganisms etc. The initial surface moisture, which is not absorbed into the soil 20, flows into the main body 1 of manhole, where the agricultural chemicals are absorbed in a layer of absorbents 6 and the purified water is discharged through a permeable cylinder 10 to a drainage system 3. And then the precipitation having lower concentration of chemicals passes the surface of the layer 6 and flows directly into the cylinder 10 from a catchment section 11, whereby the precipitation having lower concentration of chemicals is discharged into the system 3. As a result, drainage is performed corresponding to the concentration of chemicals, resulting in a improved drainage efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a water collection manhole, and more particularly to a water collection manhole suitable for installation in a golf course or the like to collect surface water containing agricultural chemicals and the like.

(Prior Art) Conventionally, hollow concrete manholes have been known as this type of water collection manhole, and when installed at a golf course, they are buried at intervals of about 40 meters, for example, and the bottom is used as a drainage system such as a drain pipe. It was supposed to be connected to a water tank to discharge wastewater for treatment.

(Problem to be solved by the invention) However, with such a water collection manhole, there is a risk that a large amount of pesticides may be contained in the wastewater discharged at the beginning of a rainfall. It was necessary to provide ancillary facilities for this purpose.

(Means for Solving the Problems) It is an object of the present invention to provide a water collection manhole that eliminates the drawbacks of the conventional water collection manholes and is particularly suitable for use in golf courses. In the center of the main body, a water-permeable cylindrical body is arranged, which has a water collection part at the upper end that makes it impossible to collect water from the sides and can collect water only from the top surface, and whose lower end is connected to the drainage system. It is characterized in that an adsorbent layer is arranged around the shaped body.

The adsorbent layer may be configured as a double layer consisting of a lower activated carbon adsorbent layer and an upper clay adsorbent layer, or a water collection pipe may be connected above the adsorption layer. You can.

(Function) At the beginning of rainfall, the precipitation with the highest pesticide concentration is absorbed into the soil and naturally decomposed by soil microorganisms, and the initial surface water that is not absorbed into the soil, that is, the precipitation with a relatively high pesticide concentration, is absorbed into the manhole body. The purified water, which has pesticides adsorbed by the adsorbent layer, is discharged into the drainage system through a permeable cylindrical body, and subsequent precipitation with a diluted pesticide concentration passes through the surface of the adsorbent layer and is collected. The water directly flows into the permeable cylindrical body and is discharged into the drainage system with a low concentration of pesticides.

When the adsorbent layer is configured as a double layer consisting of a lower activated carbon adsorbent layer and an upper clay adsorbent layer, a part of the pesticides adsorbed by the lower activated carbon adsorbent layer is absorbed into the soil. The fertilizer that is decomposed by microorganisms and adsorbed to the upper clay adsorbent layer is consumed by grass etc. planted in the soil.

Further, by connecting a water collection pipe above the adsorbent layer, excess fertilizer and agricultural chemicals contained in groundwater in the soil can be adsorbed by the adsorbent layer, and the soil condition can be maintained in good condition.

(Example) Embodiments of the present invention will be described below with reference to the accompanying drawings.

The first diagram shows an example in which the water collection manhole of the present invention is installed at a golf course. In the diagram, 1 is a cylindrical manhole body with a bottom made of concrete, and the manhole body is provided at the bottom 1a of the manhole body. The through hole 2 communicates with a drainage system 3 below, and above the through hole 2, a water permeable cylindrical body 10 made of water permeable concrete is erected in communication with this, and at the upper end of the cylindrical body 10, a side A water collection part 11 is attached that makes it impossible to collect water from the top and allows water to be collected only from the top. In the illustrated implementation, the water collection section 1
1, a drainboard 11C is disposed in the upper opening 11b of a cylindrical body 11a made of concrete. Inside the manhole body 1, an adsorbent layer 6 is arranged, which consists of a lower activated carbon adsorbent layer 4 made of granular activated carbon, powdered activated carbon, etc., and an upper clay adsorbent layer 5 made of zeolite, etc. It is set up. Further, the upper surface of the adsorbent layer 6 is filled with sand 7 in order to protect the adsorbent layer 6.

In the figure, 20 indicates soil, 21 indicates grass, and 22 indicates surface water.

According to such a water collection manhole, at the beginning of rainfall,
That is, the precipitation with the highest pesticide concentration is absorbed into the soil 20 and naturally decomposed by soil microorganisms, etc., and the initial surface water that is not absorbed into the soil 20, that is, the precipitation with a relatively high pesticide concentration, flows into the manhole body 1 and is absorbed by the adsorbent. The purified water with pesticides adsorbed by the layer 6 is discharged into the drainage system 3 through the permeable cylindrical body 10, and subsequent precipitation with a diluted pesticide concentration passes through the surface of the adsorbent material layer 6 and is collected. The drainage system 3 flows directly from the water part 11 into the water-permeable cylindrical body 10 in a state where the pesticide concentration is low.
is released into the river.

Further, the fertilizer adsorbed by the upper clay-based adsorbent layer 5 is consumed by the lawn 21 planted in the soil 20, and some of the pesticides adsorbed by the lower activated carbon-based adsorbent layer 4 are absorbed by microorganisms in the soil 20. It is decomposed by

The second diagram shows a modification of the above embodiment.
In the figure, reference numeral 13 indicates a concrete water collection pipe provided with a large number of through holes 13a, and the water collection pipe 13 is communicated with the upper part of the adsorbent layer 6. Components that are the same as those in the embodiment described above and which are not particularly described are given the same reference numerals as those in the embodiment described above, and the explanation thereof will be omitted.

According to this water collection manhole, surplus fertilizer and pesticides contained in groundwater in the soil 20 are guided into the manhole body 1 through the water collection pipe 13 and adsorbed by the adsorbent layer 6, so that the soil condition is maintained in good condition. .

(Effects) As described above, the water collection manhole of the present invention collects water according to the pesticide concentration, so surface water with a high pesticide concentration remains on the soil surface even during heavy rainfall. It has the effect of efficiently collecting water without causing any waste.

In addition, if the adsorbent layer is configured as a double layer consisting of a lower activated carbon adsorbent layer and an upper clay adsorbent layer, the fertilizer adsorbed by the clay adsorbent layer will be absorbed by the grass, etc. planted in the soil. Pesticides consumed by plants and adsorbed on the activated carbon-based adsorbent layer are decomposed by soil microorganisms, resulting in the effect that the adsorbent layer has a long life and does not require frequent replacement of the adsorbent layer.

Furthermore, if a water collection pipe is connected above the adsorbent layer, excess fertilizer and agricultural chemicals contained in groundwater in the soil can be adsorbed by the adsorbent layer, and the soil condition can be maintained in good condition. .

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of an installed state of one embodiment of the water collection manhole of the present invention, and FIG. 2 is a vertical cross-sectional view of a modified example thereof. 1... Manhole body 3... Drainage system 4... Activated carbon adsorbent layer 5... Clay based adsorbent layer 6... Adsorbent layer 7... Sand 10... Made of permeable concrete Cylindrical body 11...Water collection section 13...Water collection pipe 20...Soil 21...Grass 22...Surface water Patent application Hitogawa and 3 others Figure 1 Figure 2 == ==Koshi=〒=

Claims (1)

[Scope of Claims] 1. A water-permeable cylinder in the center of the manhole body, which has a water collection part at the upper end that makes it impossible to collect water from the sides and can collect water only from the top surface, and whose lower end is connected to the drainage system. A water collecting manhole characterized in that a cylindrical body is disposed and an adsorbent layer is disposed around the cylindrical body. 2. The water collection manhole according to claim 1, wherein the adsorbent layer is constructed as a double layer consisting of a lower activated carbon adsorbent layer and an upper clay adsorbent layer. 3. The water collection manhole according to claim 1 or 2, characterized in that a water collection pipe is communicated above the adsorbent layer.