JPS6246474Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a sewage septic tank, and more specifically, an aeration chamber and a settling chamber are formed by a partition wall with an open bottom end, and an aeration pipe is arranged in the aeration chamber perpendicular to the partition wall. Regarding sewage septic tanks.

Conventionally, as shown in Figure 1, a sewage septic tank has been widely known in which the inside of one tank is divided into a separation chamber A, an aeration chamber B, a sedimentation chamber C, a disinfection chamber D, etc., and the sewage is sequentially advected for treatment. It is being

In the aeration chamber B of the septic tank, an aeration pipe B ₁ that diffuses air into the wastewater is normally arranged, and this aeration pipe B ₁
The air bubbles ejected from the tank replenish air in the wastewater, lowering the BOD value of the wastewater, and at the same time purifying the wastewater through the action of aerobic microorganisms.
The sewage treated in the aeration chamber B is advected to the settling chamber C, the sludge remaining floating in the sewage is settled, and the treated water is discharged to the outside via the disinfection chamber D. There is.

By the way, in the aeration chamber B of the above-mentioned septic tank, a swirling flow is generated by the bubbles ejected from the aeration pipe _B1 , and as shown in Fig. 2, this swirling flow causes sedimentation to occur at the bottom surface _B2 of the tank. Branch flow towards room C
There was a problem that caused _B3 to be generated and the sludge that had settled in the settling chamber to rise again.

If such resuspension of sludge occurs in the settling chamber, the sludge will advect to the disinfection chamber D and be discharged directly from the outlet, resulting in the problem that the sewage treatment as a septic tank will not be completed. In addition to occurring,
Bubbles in the aeration chamber may also migrate to the precipitation chamber due to the above-mentioned shunt flow, and the migrated bubbles tend to cause scum to occur in the precipitation chamber.

However, in order to solve the above-mentioned problem caused by the water flow that occurs in the aeration room, the Utility Model Application No. 55-162616
53676), by providing a convex surface E on the outer surface of the septic tank and arranging the partition wall _C1 and the lower end _E1 of the convex surface E on the same plane, as shown in FIG. In order to make it difficult for the water flow to advect to the settling chamber side, the shape of the outer tank was improved and
As disclosed in No. 48398, the partition wall C ₁ is configured to have a curved surface along the swirling flow generated in the aeration chamber B, as _shown in FIG.
It has been proposed to generate a wake _C2 that is more directed toward the aeration chamber B, but the method described above requires significant changes to the mold for forming the outer tank, etc., as it is necessary to provide a protruding surface E on the outer surface of the septic tank. However, the latter method has the drawback that it is difficult to manufacture, and while the latter method does not have the above-mentioned drawbacks because only the shape of the partition wall needs to be changed, the water flow collides with the partition wall at right angles. However, as shown in FIG. 2, when the direction of the flow is parallel to the partition wall, it has almost no effect.

In view of the above-mentioned problems, this device prevents the resuspension of settled sludge in the settling chamber even when the flow direction of the swirling flow of treated sewage in the aeration chamber is parallel to the partition wall surface. The purpose of this system is to provide a sewage septic tank that can return the precipitated sludge toward the aeration chamber and also sufficiently prevent air bubbles from migrating to the settling chamber. The inside of one tank is divided by a partition wall with an open bottom end, and inside the aeration chamber,
In a sewage septic tank in which an aeration pipe is arranged in a direction perpendicular to the partition wall, a lower half of the partition wall is recessed and curved toward the settling chamber, and a lower edge thereof is bent back toward the aeration chamber. Further, a notch for regulating water flow is formed at a position corresponding to the air diffuser pipe on the lower edge.

This invention will be explained below using examples.

FIG. 5 is a cross-sectional view of an embodiment of this invention, and FIG. 6 is a perspective view of a main part of the embodiment.

In the sewage septic tank 1 of this invention, an aeration chamber 1B and a settling chamber 1C are separated by a partition wall 2 with an open bottom end, and an aeration pipe 3 is arranged in the aeration chamber 1B in a direction perpendicular to the partition wall 2. In the septic tank, the lower half of the partition wall 2 is recessed and curved in the direction of the settling chamber 1C, and its lower edge 2A is the aeration chamber 1.
It is folded back and curved toward the B side, and further this lower edge 2
A notch 4 is formed at a position corresponding to the aeration pipe 3 of A.

In the above embodiment, the horizontal position of the air diffuser 3 is as follows:
As shown in the figure, when the water depth is deep compared to the horizontal cross-sectional area of the aeration chamber 1B, it is placed above the concave curved part 2B of the partition wall 2, and as shown in FIG. In a septic tank where the water depth is shallow compared to the cross section and the hopper section 5 in the settling chamber 1C is short, the aeration pipe 3 is arranged near the lower edge of the partition wall 2.
In this case, it is desirable to integrally attach the eaves member 4A to the notch 4 as shown in FIG.

Next, the operation of the embodiment of this invention will be explained.

In FIG. 6, in the aeration chamber 1B, there is an aeration pipe 3.
This causes an upward flow P ₁ , and this upward flow P ₁ branches horizontally at the water surface into water flows P ₂ and P ₂ that descend in opposite directions and along the tank wall.
, which merges again just below the diffuser pipe 3 at the tank bottom 1' to become the above-mentioned flow _P1 .

In this swirling flow, in the part along the partition wall 2, the swirling flow becomes a flow _P3 along the recessed curved portion 2B, and this is directed toward the center of the aeration chamber 1B by the lower edge 2A of the partition wall. This causes a wake P ₄ to flow out from the precipitation chamber 1C.

On the other hand, a notch 4 is formed in the center of the lower end of the partition wall 2, and the combined swirling flow P ₂ ,
A portion of P ₂ , P ₂ ′, flows into it.

Therefore, a water flow _P6 that flows into the precipitation chamber 1C from the notch 4 and eventually flows out to the aeration chamber 1B due to the above-mentioned wake _P4 is generated, thereby causing the water flow inside the precipitation chamber 1C to flow. The precipitated sludge (not shown) flows into the aeration chamber 1B.

In addition, since the water flow P ₆ in the precipitation chamber 1C is pulled by the wake P ₄ , the water flow P 6 in the precipitation chamber 1C is
It does not reach the upper part of C, so there is no possibility of disturbing the inside of the precipitation chamber 1C.

As shown in FIG. 8, if there is no difference in height between the air diffuser 3 and the lower edge 2A of the partition wall, the eaves member 4 is designed to prevent the upward flow _P1 containing air bubbles generated above the air diffuser 3 from flowing directly into the air diffuser 3. Other than that provided is aeration room 1B,
And the water flow induced in the precipitation chamber 1C is the same as described above.

As mentioned above, this device uses the swirling flow generated in the aeration chamber to generate a flow at the bottom of the settling chamber that flows from the center of the partition wall to both sides in the width direction and flows from there toward the aeration chamber. The sediment in the settling chamber can be quickly flowed out to the aeration chamber, preventing the formation of scum due to sediment accumulation, and the strong upward flow containing air bubbles from the aeration pipe.
Since the structure prevents direct inflow of P ₁ , disturbance in the settling chamber due to air bubbles being mixed into the settling chamber is prevented, and sludge can be settled and removed reliably in the settling chamber, resulting in improved purification. This has the effect of allowing more complete processing.

[Brief explanation of the drawing]

Figures 1 to 4 are explanatory diagrams of a conventional example, Figure 5 is a sectional view of an embodiment of this invention, Figure 6 is a perspective view of the main part of the embodiment, and Figure 7 is a sectional view of another embodiment. , FIG. 8 is a perspective view of the main part of FIG. 7. 1...Sewage septic tank, 1B...Aeration room, 1C...
Sedimentation chamber, 2...partition wall, 2A...lower edge of partition wall,
3... Diffusion pipe, 4... Notch, P ₁ , P ₂ , P ₃ ,
P ₄ , P ₅ , P ₆ ...water flow.

Claims (1)

[Scope of utility model registration request] In a sewage septic tank in which an aeration chamber and a settling chamber are partitioned in one tank by a partition wall with an open bottom end, and an aeration pipe is arranged in the aeration chamber in a direction perpendicular to the partition wall, the partition The lower half of the wall is curved in a concave direction toward the precipitation chamber, and the lower edge thereof is bent back toward the aeration chamber, and further,
A sewage septic tank characterized in that a notch is formed on the lower edge at a position corresponding to the aeration pipe.