JPS5837512Y2 - Sewage septic tank - Google Patents

Description

[Detailed explanation of the idea] This invention relates to the improvement of an aerated sewage septic tank.

FIG. 1 shows a conventional aeration type sewage purification tank using an aeration pipe, in which an aeration chamber 1' and a settling chamber 2' are separated by a partition wall 3'.

Reference numeral 4' indicates an aeration pipe provided in the aeration chamber 1', and 5' indicates an air supply pipe. Air from the air supply pipe 5' is discharged from the aeration pipe 4' as small bubbles.

In the aeration chamber 1', activated sludge flocs are mixed with organic matter in the sewage due to the stirring and mixing effect of the one-sided swirl flow caused by the upward flow caused by the small bubbles from the aeration chamber 4' and the oxygen supply effect from the air bubbles. adsorbs, oxidizes and decomposes it into inorganic form.

On the other hand, in the settling chamber 2', the treated water is clarified and separated by coagulation and sedimentation of suspended flocs.

In the precipitation chamber 2', a circulation flow shown as A' in the figure is generated due to the suction action of the one-sided swirl flow in the aeration chamber, and the precipitation chamber 2'
The sludge that settles at the bottom of the aeration chamber 1 flows through the flow a'.
' will be returned to .

By the way, in conventional aeration-type sewage septic tanks, the circulating flow A' in the settling chamber spreads to a considerable upper part of the settling chamber 2', and the clarified layer is disturbed and sludge often mixes into the clarified layer. This is happening.

The aeration type sewage septic tank according to the present invention has a configuration that can alleviate the above-mentioned disadvantages, and a bay-shaped notch is provided at the lower end of the partition between the aeration chamber and the settling chamber, and the settling chamber is provided around the notch. The device is characterized in that a stiffener is provided on the side and a current plate is provided between the notches.

The present invention will be explained below with reference to the drawings.

FIG. 2A is a cross-sectional view showing a sewage septic tank according to the present invention.

FIG. 2B is a sectional view taken along line BB in FIG. 2A, and FIG. 2C is a sectional view taken along line CC in FIG. 2A.

In FIGS. 2A to 2C, 1 is the tank body.

2 is a partition wall, and the inside of the tank body 1 is divided into an aeration chamber 10 and a precipitation chamber 20 by this partition wall 2.

4.4... is a bay-shaped notch provided at a predetermined interval at the lower end of the partition wall 2, and this notch includes:
As shown in FIG. 3, stiffeners 5, 5 are provided which have an inverted C-shape and are squeezed out toward the precipitation chamber side.

Reference numeral 7 denotes an overflow weir provided at the upper part of the partition wall 2, and is provided with a large number of V-notches.

Reference numeral 101 denotes a disinfection chamber, in which the clarified liquid in the settling chamber 20 overflows the overflow weir 7 and is transferred into the disinfection chamber 101.

6. . . . is a current plate provided at the lower part of the precipitation chamber, and is present between the above-mentioned bay-shaped notches 4, 4 at the lower end of the partition wall.

8. ...... is an aeration pipe installed in the aeration room,
It is communicated with the air pipe 81.

9 is a wastewater inflow pipe. In the above, a unidirectional swirling flow is generated in the aeration chamber 10 due to the upward flow caused by the small bubbles from the aeration pipe 8 .

This one-sided swirling flow moves along the partition wall 2, and when it leaves the lower end of the partition wall, the liquid in the lower part of the precipitation chamber is sucked, and a circulating flow A is also generated in the lower part of the precipitation chamber.

In this case, as shown in FIG. 4, the suction flow becomes a radial flow because the lower end of the partition wall is cut into a bay shape.

However, in a radial flow, the upstream part away from the center is a low-velocity flow.

Thus, a strong circulation flow can be generated in the lower part of the settling chamber while keeping the upper part of the settling chamber substantially stationary.

Therefore, the settled sludge in the lower part of the settling chamber can be reliably returned to the aeration chamber without disturbing the clarified layer in the upper layer of the settling chamber.

At this time, the one-arm circulation in the aeration chamber 10 that causes the radial flow is turned into a centripetal flow by the stiffener 5 when it leaves the lower end of the partition wall 2, and the rectifier plates 6, 6 provided between the bay-shaped notches
Since mutual flow interference is prevented, the above-mentioned radial flow is efficiently generated.

As described above, in the aeration type sewage septic tank according to the present invention, the sludge in the settling chamber can be returned to the aeration chamber without disturbing the clarification layer in the settling chamber, and the clarification process can be performed satisfactorily.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing a conventional aeration type sewage septic tank, Fig. 2 A is an explanatory diagram showing a sewage septic tank according to the present invention, and Figs. 2B and 2C are B-B cross sections in Fig. 2A. FIG. 3 is an explanatory view showing a bay-shaped notch at the lower end of the partition wall in the present invention, and FIG. 4 is an explanatory view showing the state of liquid flow at the same notch. In the figure, 10 is an aeration chamber, 20 is a precipitation chamber, 2 is a partition wall,
4, 4 is a bay-shaped notch.

Claims (1)

[Scope of utility model registration request] A bay-shaped notch is provided at the lower end of the partition wall between the aeration chamber and the settling chamber, a stiffener squeezed toward the settling chamber is provided around the notch, and a current plate is arranged between the notches. A sewage septic tank characterized by the fact that it has been installed.