JPH038324Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a sedimentation separator, and particularly to a sedimentation separator that performs wastewater treatment by precipitating, separating, and removing turbid substances such as wastewater.

[Background of the idea]

Generally, a sedimentation separator is used as a treatment device for removing turbidity from wastewater, and conventionally, this type of sedimentation separator has a treated water overflow weir 10 formed at the upper edge, as shown in Fig. 4. A raw water inflow pipe 14 and a sludge withdrawal pipe 16 are connected to the sedimentation separation tank 12 at the bottom thereof. A discharge groove 18 is formed on the outer periphery of the upper edge of the sedimentation separation tank 12 for discharging the treated waste water overflowing from the treated water overflow weir 10, that is, the treated water, to the outside of the sedimentation separation apparatus.

In the sedimentation separation device, wastewater flows into the sedimentation separation tank 12 from the raw water inflow pipe 14, turbidity in the wastewater is precipitated and separated in the sedimentation separation tank 12, and the sedimentation separation tank is connected to the sedimentation separation tank from the sludge withdrawal pipe 16. The supernatant is discharged to the outside of the sedimentation separation tank 12, while the supernatant is treated as treated water at the treated water overflow port 1.
0 and discharged from the discharge groove 18 to the outside of the sedimentation separator for wastewater treatment. The removal rate of suspended solids in the waste water of the sedimentation separation device is greatly influenced by the relative relationship between the sedimentation rate of suspended solids and the rising rate of water in the sedimentation separation tank 12. For example, if the sedimentation rate of turbidity in the wastewater is higher than the rate of rise of water in the sedimentation separation tank 12, it will easily settle and be separated, and conversely, if the sedimentation rate of turbidity in the wastewater is lower The turbidity rises with water, and the treated water overflow weir 10
Since more water flows out, the removal rate of suspended solids in wastewater becomes lower. Therefore, in order to maintain a constant removal rate of turbidity in wastewater, it is necessary to equalize the rate of rise of water.
The rising speed of water is set in consideration of the settling speed of turbidity.

However, the sedimentation separation device has a large difference between the temperature of the waste water in the sedimentation separation tank 12 and the temperature of the outside air, for example, when the waste water is heated, or when it is installed at night, in winter, or in a cold region where the outside air temperature is low. Become,
A thermal convection phenomenon, as shown by the dotted line in Figure 4, occurred during the drainage in the sedimentation separation tank 12, which disrupted the uniformity of the water's rising speed, and the turbidity in the wastewater could not be removed as expected. . For this reason, even if measures such as installing the entire sedimentation separator indoors or covering the entire surface are taken, a high cost is required and the effects are small.

In addition, in Japanese Patent Publication No. 47-33094, floating objects,
For example, it has been disclosed that wood, bamboo, synthetic resin, or the like is floated on the surface of the treated water to keep the treated water warm.

However, in Japanese Patent Publication No. 47-33094,
Although it is disclosed that a shielding material is suspended above the treated water, it is not disclosed how to apply this shielding material to a sedimentation separator. That is, even if floating objects are floated in the sedimentation separator 12 shown in FIG. 4, there is a problem that the floating objects flow out over the overflow weir 10 together with the supernatant water due to the influence of wind or the like.

[Purpose of invention]

The present invention was developed in view of these circumstances, and the removal rate of turbidity in wastewater is not affected by the temperature conditions of the wastewater or the outside air temperature, and the floating matter in the sedimentation separation tank does not flow out. The purpose is to provide a sedimentation separation device.

[Summary of the idea]

In order to achieve the above object, the present invention provides a sedimentation separation tank in which a sludge withdrawal pipe is connected to the raw water inlet and the lower part, and a treated water overflow weir is formed at the upper edge, and the raw water stored in the sedimentation separation tank. In a sedimentation separator configured with small pieces of floating material, which is installed to cover the liquid surface of A space is provided between the weir and the weir for supernatant water to flow out, the lower end of the holding plate is extended to form a still water area below the floating object, and a net is stretched over the upper surface of the floating object.

〔Example〕

Hereinafter, preferred embodiments of the sedimentation separator according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a cross section of a main part of a sedimentation separator according to a first embodiment, for example, a cylindrical sedimentation tank 2.
An overflow weir 22 is provided on the upper edge of 0, and a retaining plate 24 that is taller than the overflow weir is provided inside this overflow weir 22. Furthermore, a spherical weir is placed on the liquid surface of the waste water 26 stored in the sedimentation separation tank 20. A floating object 28 is arranged, and the floating object 28 is held by the holding plate 24. The floating objects 28 are made of hollow objects of various diameters, such as spherical objects, plate-like objects, and ping-pong balls made of foamed polystyrene, etc., which have an excellent heat insulating effect. Covers the surface. The retaining plate 24 is formed to be inclined outwardly, and is
The overflow weir 22 and the retaining plate 24 are provided in parallel with each other at a constant interval A from the horizontal plane, and are formed to be inclined outward at an inclination angle of about 70 degrees from the horizontal plane. Interval A serves as a drainage channel for supernatant water. A net 30 made of metal or plastic is provided on the upper edge of the holding plate 24 to cover the floating objects 28 for the purpose of preventing the floating objects 28 from flowing out. As a result, the floating objects 28 are arranged in an orderly manner on the water surface, and have a high heat retention effect, and are not blown away by wind or the like. During normal wastewater treatment, the sedimentation separator has a retaining plate 24 and an overflow weir 2.
Between A and 2, treated wastewater, ie, treated water, overflows from A.

The lower end of the retainer plate 24 extends, and a still water area 26A is formed below the floating object 28 and surrounded by the lower end of the retainer plate 24. Such a still water area 26A is a part where water does not flow, and floating matter with a light specific gravity and floating matter accompanied by air bubbles in the treated water are collected here. When the fine suspended matter aggregates into large clumps, they move toward the bottom of the tank against the upward flow and are separated.

Furthermore, a discharge groove 32 is provided on the outer side of the upper edge of the sedimentation separation tank 20, so that the treated water flowing out from the overflow weir 22 is discharged to the outside of the sedimentation separation apparatus.
Further, in the sedimentation separation tank 20, a sludge withdrawal pipe (not shown) for discharging the sedimented and separated suspended matter as sludge is provided at the lower end of the tank 20, and between the drain groove 32 and the sludge withdrawal pipe, the waste water 26 is separated by sedimentation. Raw water inflow pipes (not shown) for supplying into the tank 20 are connected to each other.

Next, the operation of the sedimentation separator according to this embodiment configured as described above will be explained.

The sedimentation separator continuously supplies wastewater 26 containing turbidity into the sedimentation separation tank 20 from a raw water inflow pipe (not shown), settles and separates the turbidity 27 of the supplied wastewater 26, and produces supernatant water. The precipitated turbidity 27 is discharged as treated water from the overflow weir 22 through a sludge extraction pipe (not shown) to perform wastewater treatment. At this time, the waste water 26 of the sedimentation separation tank 20 is isolated from the outside air by the floating objects 28 on the liquid surface, so it is not directly affected by the outside temperature and is maintained at a constant temperature, thereby preventing thermal convection. Therefore, the moisture in the waste water 26 rises uniformly, while the suspended matter 27 easily settles and is separated. In particular, since the still water area 26A is formed by the lower end of the retaining plate 24, this still water area 26A
As a result, fine suspended matter coagulates, falls, and is collected at the bottom of the tank, improving sedimentation efficiency.

The sedimentation separation device according to this embodiment includes a sedimentation separation tank 2
Since a heat convection phenomenon does not occur in the waste water 26 in the waste water 26, the rate of rise of water in the waste water 26 can be easily set, for example, by adjusting the supply amount and temperature of the waste water 26.

In this embodiment, the inclination angle of the overflow weir 22 and the retaining plate 24 is approximately 70 degrees, but it is not limited to this, and may be between 30 degrees and 90 degrees.

FIG. 2 shows a cross section of a main part of a sedimentation separator according to a second embodiment of the present invention, in which a three-stage overflow structure is used instead of the overflow weir 22 provided in the sedimentation separator according to the first embodiment. A weir 34 is provided.

The overflow weir 34 is a weir plate 3 that slopes inward of a lower overflow weir 36 that is integrally formed on the upper edge of the sedimentation separation tank 20.
8 and 40 are provided in sequence, and a holding plate 42 is provided inside the weir plate 40 to hold floating objects 28 made of styrofoam spheres, etc., as in the first embodiment. . Each of the overflow weirs 36, 38, 40 and the holding plate 42 are formed to be inclined outward at an angle ranging from 30 degrees to 90 degrees from the horizontal plane, and each of the overflow weirs 36, 38, 40
The interval B between the holding plates 42 is formed to be smaller than the diameter of the floating object 28, so that the floating object 28 is prevented from flowing out. The floating objects 28 are covered with a net 30 to prevent them from flowing out from the upper holding plate 42.

The sedimentation separator according to this embodiment shown in FIG.
In addition to the heat retention effect of 6, since the overflow weir 34 is structured in three stages, the liquid level in the sedimentation separation tank 20 is
Even if the floating objects 28 are lowered, they do not flow out from between the overflow weirs 34.

FIG. 3 shows a cross section of a main part of a sedimentation separator according to a third embodiment of the present invention, in which the inclined retaining plate 24 provided in the sedimentation separator according to the first embodiment of FIG. A vertical holding plate 44 is provided.

The holding plate 44 is a floating object 28 provided on the liquid level in the sedimentation separation tank 20 as in the first and second embodiments.
... are held, and the floating objects 28 ... are covered with a net 30 to prevent them from flowing out.

In the sedimentation separator according to the present embodiment shown in FIG. The heat retention state of the waste water 26 is good.

In the second embodiment shown in FIG. 2 and the third embodiment shown in FIG.
A is formed, aggregates into fine floating particles, falls down, and is collected below.

Note that the first to third points shown in FIGS. 1 to 3
The floating objects 28 provided in the embodiment are spherical,
It may be configured by combining objects having various shapes such as a plate shape and a fragment.

[Effect of idea]

As explained above, the sedimentation separator according to the present invention is configured to include floating objects on the surface of raw water such as drainage water of the sedimentation separation tank whose upper edge is used as a treated water overflow weir.
The waste water in the sedimentation separation tank is isolated from the outside air by floating objects and maintained at a constant temperature, preventing water heat convection, which equalizes the rate of rise of water in the waste water and removes turbidity. The rate can be maintained constant regardless of the temperature conditions of the wastewater and the outside air temperature, resulting in excellent treatment effects.

Furthermore, since the sedimentation separator according to the present invention only provides floating matter on the drainage surface in the sedimentation separation tank,
It can be manufactured at low cost.

Furthermore, in the sedimentation separator according to the present invention, a retaining plate taller than the overflow weir is provided inside the overflow weir, so that it is possible to prevent floating substances from flowing out.

According to the sedimentation separation device of the present invention, since the net covers the floating objects, the floating objects are arranged neatly on the water surface, and the heat retention effect of the floating objects is high, and the floating objects are not washed away by wind etc. do not have.

Furthermore, according to the sedimentation separator according to the present invention, a still water area is formed below the floating objects by extending the lower end of the retaining plate, so that floating objects with light specific gravity and air bubbles in the treated water are collected in this area. Things can be collected. When fine suspended matter aggregates into large clumps, they move toward the bottom of the tank against the upward flow and settle and separate, increasing the treatment effect.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the main parts of a sedimentation separator according to the first embodiment of the present invention, Fig. 2 is a sectional view of the main parts of the sedimentation separator according to the second embodiment, and Fig. 3 is a sectional view of the main parts of the sedimentation separator according to the second embodiment. FIG. 4 is a cross-sectional view of a main part of such a sedimentation separation apparatus, and FIG. 4 is a sectional view showing a conventional sedimentation separation apparatus. 20... Sedimentation separation tank, 22, 34, 36, 3
8,40...Overflow weir, 24,42,44...Retention plate, 26...Drainage, 26A...Still water area, 28...
...Floating object, 30...net.

Claims (1)

[Scope of claim for utility model registration] A sludge extraction pipe is connected to the raw water inlet and the lower part,
A sedimentation separation tank with a treated water overflow weir formed on the upper edge;
In a sedimentation separation device configured with small pieces of floating matter, which are provided to cover the surface of the raw water stored in the sedimentation separation tank, the floating matter is floated by a retaining plate taller than the overflow weir. In addition to surrounding the object, a space is provided between the retaining plate and the overflow weir for supernatant water to flow out, the lower end of the retaining plate is extended to form a still water area below the floating object, and a net is placed on the top surface of the floating object. Sedimentation separation equipment characterized by its tension.