JPS6265789A - Structural body for cleaning up waste water - Google Patents

Abstract

PURPOSE:To extend the sevice life of a titled body and to permit the easy embedment thereof in a horizontal state by mounting a water impermeable rigid body to the outside peripheral surface in the lower part of a water permeable tubular body so that the clogging by sludge-like scum and anaerobic microorganisms hardly arises. CONSTITUTION:The water impermeable rigid body 3 is mounted to the outside peripheral surface in the lower part of the water permeable tubular body 2 having through-holes 1. As a result, the clogging by the sludge-like scum and anaerobic microorganisms hardly arises and the service life is longer. The embedment and installation of the structural body in the horizontal state are easy; in addition, the structural body is hardly deformable by land subsidence and load bearing after the embedment.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention utilizes the action of microorganisms in the soil, soil adsorption, filtration action, etc. by infiltrating and dispersing various wastewater such as sewage into soil. This invention relates to an improvement in a wastewater purification structure that purifies wastewater.

[Conventional technology]

Conventionally, on the side of a long cylindrical body made of a non-woven filter,
Wings made of a non-woven filter are formed to protrude, and a water-impermeable sheet is attached to the bottom of the cylindrical body, so that the wastewater supplied into the cylindrical body is purified in the soil through a so-called "water channel". There is a known sewage purification structure that prevents sewage from flowing directly into the underground water vein.
(Special Publication No. 56-48230).

[Problem that the invention seeks to solve]

This structure can effectively infiltrate wastewater into the soil and has an excellent wastewater treatment effect, but because it uses a cylindrical body and wing pieces made of non-woven filters, it is difficult to prevent sludge-like scum from forming. It is easy to get clogged, and because sewage is constantly infiltrating the upper nonwoven fabric, the surrounding soil becomes anaerobic over time, and the water permeability of the soil decreases significantly due to the mucus secretions of anaerobic microorganisms. Combined with this, there is a problem in that the siphon effect of the nonwoven filter, that is, the ability to suck up wastewater and cause it to evaporate and infiltrate into the soil, decreases in a short period of time, making it impossible to perform satisfactory wastewater treatment.

Furthermore, when burying this structure in the soil, the ground at the buried part should be sufficiently compacted so that the structure remains horizontal, and the structure with a length of about 4 to 30 cA should be placed on top of it. The tamping work is done by joining the concrete to a specified length, but this tamping work requires a lot of effort and cannot be done in rainy weather.
There is also the problem that the permeability of wastewater deteriorates and the wastewater treatment capacity decreases.

In addition, even if the ground is compacted with great care,
It is extremely difficult to bury a structure horizontally, and if the structure is not kept level, sewage will concentrate in the deeply buried parts of the structure, and the drainage load will be distributed evenly along the length of the structure. The problem is that it doesn't work.

Furthermore, even if the structure is buried horizontally, if the ground subsides afterwards, or if a heavy object such as a car passes over the ground and loads are applied to the structure,
The structure is easily deformed and its horizontal state is disrupted, and connections in the structure can become disconnected, causing problems such as drainage leaking from those parts.

The purpose of the present invention is to solve the problems of conventional wastewater purification structures, prevent clogging caused by sludge-like scum and anaerobic microorganisms, have a long service life, and allow the structure to be buried horizontally and constructed. To provide a wastewater purification structure that is easy to install and is difficult to deform due to ground subsidence or load application after being buried.

[Means for solving problems]

As a result of extensive studies to achieve this objective, the present inventors did not use a cylindrical body or wing pieces of a nonwoven fabric filter like conventional structures, but instead used a water-permeable tubular body and The inventors have discovered that a water-impermeable rigid body can be used instead of a flexible water-impermeable sheet, and have arrived at the present invention.

That is, the invention of the present invention tube 1 is a waste water purification structure characterized in that a water-impermeable rigid body is attached to the lower outer circumferential surface of a water permeable tubular body, and the invention of the present subject tube 2 is a waste water purification structure characterized in that a water impermeable rigid body is attached to the lower outer circumferential surface of a water permeable tubular body. A water-based rigid body is attached to the outer peripheral surface of the lower part, and a soil layer with an infiltration rate of 1.3 to 15 marks/hour and a saturated water permeability coefficient of 1.5 x 10-6 cm/sec or more is formed on the outer periphery of the tubular body. This is a wastewater purification structure characterized by the following:
The invention is a wastewater purification structure characterized in that a water-impermeable rigid body is attached to the lower outer peripheral surface of a water-permeable tubular body, and a water-supplying sheet is disposed at the lower part of the rigid body.

Hereinafter, the water permeation purification structure of the present invention will be explained based on the drawings.

FIG. 1 is a perspective view showing an example of a wastewater purification structure according to the invention of the present invention, and FIG. 2 is a cross-sectional view thereof. A rigid body 3 is attached.

The water-permeable tubular body 2 is a tubular body (usually made of synthetic resin) having a large number of water-permeable holes as shown in FIGS. 1 and 2.
In addition, synthetic resin bristle fibers are assembled into a cylindrical shape using a stringing machine to form a cylindrical body with a braid-like wall surface, and synthetic resin is melted and discharged in a linear manner and fused into a cylindrical shape to form a cylindrical body with a porous wall surface. Any tubular body having water permeability, such as a tubular body, can be used. The cross-sectional shape of the water-permeable tubular body is most preferably circular in order to prevent deformation under load as much as possible, but it can be any shape as necessary, such as polygonal or elliptical. .

The water-impermeable rigid body 3 is a member that does not allow water to pass through and is not flexible, and usually a synthetic resin gutter-like body with a thickness of about 1 to 5 mm is preferably used. As shown, a water-permeable tubular body 2 having a large number of water-permeable holes 1 has a water-permeable tubular body 2 on its lower outer circumferential surface and an upper part of the water-permeable tubular body 2.
A trapezoidal water-impermeable rigid body 3 may be provided having a receiving portion 3' into which the water-impermeable body 3 is fitted.

The trapezoidal water-impermeable rigid body 3 is preferably made of expanded polystyrene.

The outside of the water-permeable tubular body 2 is provided with a third hole in order to prevent soil and plant roots from entering the water-permeable tubular body 2 through the water-permeable hole 1.
As illustrated in the figure, it may be covered with a covering 4 such as a net, woven or knitted fabric, or non-woven fabric.

Furthermore, when draining water into the water-permeable tubular body 2, it is preferable to form an air layer in the upper part of the tubular body 2 in order to leave room for intermittent drainage.

FIG. 4 is a sectional view showing an example of a wastewater purification structure according to the second invention of the present application, in which a water-impermeable rigid body 3 is attached to the lower outer peripheral surface of a water-permeable tubular body 2 having a large number of water-permeable holes 1. , furthermore, the infiltration rate on the outer periphery of the tubular body 2 is 1.3 to 25 cm/hour,
Preferably 1.4 to 5.0 cm/hour, saturated water permeation rate of 1.5×10-”C1117 seconds or more, preferably 3.
A soil layer 5 of 5×10-'cffl/sec or more is formed and buried in the land 6. This soil layer 5 promotes the infiltration and diffusion of wastewater from the permeable tubular body 2 into the soil. If the infiltration rate of the soil layer 5 is too high, the organic matter in the wastewater will not be sufficiently decomposed by microorganisms. , 'The purification effect will be insufficient; on the other hand, if it is too small, the wastewater will not infiltrate and diffuse into the soil, making it anaerobic, and clogging will occur with mucus secreted by anaerobic microorganisms, which will also reduce the purification effect. In addition, if the saturated hydraulic conductivity is too small, the amount of drainage from the permeable tubular body 2 to the soil layer 5 will be small, resulting in a decrease in wastewater treatment capacity.On the other hand, if it is too large, the infiltration rate will be too high, reducing the effectiveness of wastewater purification. descend.

The infiltration rate is measured by the apparatus shown in FIG. In Fig. 6, 11 is a graduated cylinder with a capacity of 41;
13 is a plug provided at the top of the measuring cylinder 11, 13 is a ventilation pipe passed through the plug 12, and 14 is a diameter of 100 fl and a height of 750 mm.
In the cylindrical glass column of Tsuru, 15 is glass wool, and 16 is a conduit for supplying water from the bottom of the graduated cylinder 11 to the glass column 14. When measuring, glass column 1
4 is filled with sample soil, water is poured into the graduated cylinder 11, and the mixture is left in a room at a temperature of 20±1°C and a relative humidity of 60±5%. Let it infiltrate inside.

Determine the maximum distance h (cod) that water reached by infiltrating and rising in the sample soil in the glass column 14 and the time t (cod) required for water to infiltrate to the maximum reaching distance, h/l.
(cm/hour) is the infiltration rate. On the other hand, the saturated hydraulic conductivity is calculated by filling the upper part of the sample soil column with water and letting the water flow down into the sample soil column.
K=Q1/Aht (Q
; water flow rate (CC), l ; thickness of sample soil column (cm), A; cross-sectional area of sample soil column (c
ll, h; water level difference (cod), t; time (seconds)
] is required.

Examples of the results of measuring the infiltration rate and saturated hydraulic conductivity of various soils are as follows.

Gravel (diameter 2cm or more) - Single medium sandy soil 2.91.0XlOpe sandy loam
3.0? , 4X10-' Silty Pure Land 3', 4 9.3XIO-'
Loam 2.0 4.3 X 1
0-' Sandy loam soil 1.7 3.6
X 10-' Silty soil 1.4
1.0X10-' planting soil 1.4
5.3X10-b sandy planting soil 1.3 2.5
10-h Silty planting soil 1.3 2.
0xlO-'Light planting soil 1.4 3
．． 8 x 10-' heavy planting soil 1.2
4.2X10-" In the present invention, the soil that can be used as the soil layer 5 is sandy soil to sill l-9 planted soil, preferably loamy sandy soil to planted soil, and the gravel has a high infiltration rate and a saturated hydraulic conductivity. It cannot be measured, and river sand is inappropriate because both its infiltration rate and saturated hydraulic conductivity are too large.

In addition, the saturated hydraulic conductivity of light planted soil is too low, and the infiltration rate and saturated hydraulic conductivity of heavy planted soil are too small, making it unsuitable.

In addition, as the soil layer 5 of the present invention, industrial waste such as clinker or a pot residue layer generated in the paper manufacturing process can also be used as long as the infiltration rate and saturated hydraulic conductivity are within the range of the present invention. . The thickness of the soil layer 5 is not particularly limited, but is usually 10 cm or more. Furthermore, it is not necessarily necessary that the soil layer 5 covers the entire surface of the water-permeable tubular body 2, and the effect of the present invention can be sufficiently achieved even if the soil layer 5 covers only a part of the water-permeable tubular body 2. sexual tubular body 2
Preferably, at least 50% of the surface area of the soil layer 5 is covered by the soil layer 5.

FIG. 5 is a cross-sectional view showing an example of the wastewater purification structure of the invention of the present invention, in which an impermeable rigid body 3 is attached to the lower outer peripheral surface of a water permeable tubular body 2 having a large number of water permeable holes 1, Furthermore, a water-absorbing sheet 7 is disposed below it. This water-absorbing sheet 7 infiltrates and diffuses wastewater over a wider area in the soil, making the purification process of wastewater in the soil more effective.It usually has a thickness of 3 to 20 inches and has an apparent specific gravity. 0.
05 or higher synthetic fiber nonwoven fabric is used.

In particular, polyester fiber nonwoven fabric is suitable.

Further, when the diameter of the water-permeable tubular body 2 is 75 mm, the appropriate width of the water-absorbing sheet 7 is about 50 cm.

[Effect]

Next, the operation of the wastewater purification structure of the present invention will be explained.

First, the wastewater purification structure of the present invention is buried approximately 40 cm underground, but in this case there is no need to compact the ground, and first, the impermeable rigid body 3 is laid horizontally. Next, a plurality of water-permeable tubular bodies 2 are fitted into the water-impermeable rigid body 3, and the joints of adjacent water-permeable tubular bodies 2 are joined by any means such as adhesive tape to drain a predetermined length. Use as a processing structure.

In the case of the invention of the present cylinder 2, around the water permeable tubular body 2,
Infiltration rate 1.3-15cm/hour, saturated hydraulic conductivity 1,
A soil layer 5 of 5×IQ-6 am/sec or more is formed.

Further, in the case of the invention of the cylinder 3 of the present application, the water-absorbing sheet 7 is buried under the water-impermeable rigid body 3.

After the wastewater purification structure is buried underground in this manner, wastewater is supplied into the water permeable tubular body 2. The wastewater supplied into the water permeable tubular body 2 infiltrates and diffuses into the soil through the water permeable holes 1 while flowing inside the water permeable tubular body 2 (the water permeable tubular body 2
When a soil layer 5 having a specific range of infiltration rate and saturated hydraulic conductivity is formed around the outer periphery of the soil layer 5, due to the capillary phenomenon of the soil layer 5,
Infiltration and diffusion of drainage water in all directions in the soil is promoted.

In addition, when the water-absorbing sheet 7 is arranged under the water-permeable tubular body 2, the wastewater discharged from the water-permeable tubular body 2 into the soil through the water permeable holes 1 reaches the water-absorbing sheet 7. The capillary action of the water-absorbing sheet 7 allows wastewater to infiltrate and diffuse over a wider area in the soil, making it possible to purify the wastewater in the soil more efficiently.

Further, the lower outer circumferential surface of the water-permeable tubular body 2 is formed by the water-impermeable rigid body 3.
This prevents the wastewater supplied into the permeable tubular body 2 from being purified in the soil (and from flowing directly into the groundwater vein), with a so-called "water path". Ru.

As wastewater infiltrates and infiltrates the soil near the surface of the earth while breathing in air, aerobic microorganisms thrive, decomposing organic matter in the wastewater, and purifying it. There is no clogging or odor caused by the growth of anaerobic microorganisms.

The purified wastewater may be allowed to permeate underground as is in an open system, or may be collected in a collection pipe and reused in a closed system.

〔Effect of the invention〕

The wastewater purification structure of the present invention does not use a cylindrical body or wing pieces made of a non-woven filter, but instead uses a water-permeable tubular body. Therefore, soil filtration is carried out in a wide area of the surrounding soil, and the aerobic microorganisms associated with it are treatment is carried out, clogging with sludge-like scum hardly occurs, and the service life of the armor is greatly extended.

In addition, conventional wastewater purification structures using cylindrical bodies and wing pieces made of non-woven filters become clogged with sludge-like scum after about 6 months of use, and are no longer able to perform their normal wastewater purification function. However, according to the wastewater purification structure of the present invention, there is no sign that the soil becomes anaerobic even after one year has passed since the start of use, there is almost no clogging of the soil, and normal wastewater purification treatment can be carried out. It can be carried out.

Furthermore, in the wastewater purification structure of the present invention, the impermeable rigid body 3 is attached to the outer peripheral surface of the lower part of the permeable tubular body 2, so the impermeable rigid body 3 is attached without compacting the ground. By simply laying the structure and fitting the water-permeable tubular body 2 thereon, a satisfactory horizontal state can be obtained, and the work of burying the structure in the soil is significantly simplified. Furthermore, since it is not necessary to compact the ground, the permeability of wastewater is not inhibited, and the wastewater purification ability is not reduced.

In addition, since a sufficient horizontal state can be easily obtained, the drainage load can be applied uniformly along the length of the structure, and drainage will not be discharged into the soil from only a portion of the structure.

Furthermore, since the permeable tube body 2 is reinforced by the impermeable rigid body 3, even if the ground subsides after the structure is buried or a load is applied to the structure due to passing cars, etc., the structure will remain intact. There will be no problems such as the body being deformed and the horizontal state being broken, or the connection part of the structure coming off and drainage leaking from that part.

Furthermore, when drainage water is supplied into the permeable tubular body 2, if an air layer is formed in the upper part of the tubular body 2, the amount of drainage can be changed considerably due to the presence of the air layer, and intermittent drainage can be prevented. Even if you go there, you can fully cope with it.

Furthermore, in the second invention of the present application, the soil layer 5 having a specific infiltration rate and saturated hydraulic conductivity is formed on the outer periphery of the permeable tubular body 2, so that infiltration and diffusion of wastewater into the soil is promoted. At the same time, the decomposition of organic matter by microorganisms is sufficiently performed, and the purification effect can be improved.

In addition, in the third invention of the present application, since the water-absorbing sheet 7 is disposed under the water-permeable tubular body 2, the drainage water can be infiltrated and diffused over a wider range in the soil. The purification treatment of wastewater can be carried out more efficiently.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an example of the wastewater purification structure of the first invention of the present application, Fig. 2 is a sectional view thereof, and Fig. 3 shows another example of the wastewater purification structure of the zero-jaw first invention. A cross-sectional view, FIG. 4 is a cross-sectional view showing an example of the wastewater purification structure of the second invention of the present application, and FIG.
The figure is a sectional view showing an example of a wastewater purification structure according to the third invention of the present application, and FIG. 6 is a sectional view of an infiltration rate measuring device. 1...Water permeable hole 2...Water permeable tubular body 3...Water impermeable rigid body 5...Soil layer 7...Water absorbent sheet patent applicant Daiki Co., Ltd. agent Patent attorney Takashi Shige Shige 1 Figure 2 @ Figure 4 Figure 5 Figure 6

Claims (8)

[Claims] (1) A wastewater purification structure characterized in that a water-impermeable rigid body is attached to the lower outer peripheral surface of a water-permeable tubular body. (2) The wastewater purification structure according to claim 1, wherein the water-impermeable rigid body has a gutter shape. (3) The wastewater purification structure according to claim 1, wherein the water-impermeable rigid body has a trapezoidal shape with a receiving portion for the water-permeable tubular body at the upper part. (4) The water distribution purification structure according to claim 1, 2, or 3, wherein an air layer is formed in the upper part of the water permeable tubular body. (5) A water-impermeable rigid body is attached to the lower outer circumferential surface of the water-permeable tubular body, and an infiltration rate of 1.3
~15cm/hour, saturated hydraulic conductivity 1.5×10^-^6
A wastewater purification structure characterized by forming a soil layer of cm/sec or more. (6) soil layer infiltration rate of 1.4 to 5.0 cm/hour;
The wastewater purification structure according to claim 5, having a saturated hydraulic conductivity of 3.5 x 10^-^6 cm/sec or more. (7) A wastewater purification structure characterized in that a water-impermeable rigid body is attached to the outer peripheral surface of the lower part of the water-permeable tubular body, and a water-absorbing sheet is disposed below the rigid body. (8) The wastewater purification structure according to claim 7, wherein the water absorbent sheet is a synthetic fiber nonwoven fabric.