JPH09122677A - Aeration tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent foamed scum from staying by making a flow on a water surface smooth. SOLUTION: In an aeration tank 1 wherein a central partition wall 5 and a stirring type aerator 2 are installed in a cylindrical horizontal water tank having end plates in front and in rear, and biological treatment is carried out with activated sludge by forming a circulating water channel, in order to guide a flow of a scum floating on a water surface, an arcuate guide plate 3 is fitted above and below the water surface in front of the end plates of corner parts at two positions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aeration tank, and more particularly, to an aeration tank in which scum is generated or in a sewage treatment plant in which scum is predicted to be generated and which is capable of reliably crushing scum. Is.

[0002]

2. Description of the Related Art In a conventional circular horizontal aeration tank, as shown in FIGS. 4 and 5, a partition wall 5 is arranged at the longitudinal center of the aeration tank 1, and a corner portion inside the aeration tank 1 is close to a rectangle. A circulating water channel 13 is formed as a shape, and one or more agitating aerators 2 are provided in this circulating water channel.
Sewage is caused to flow into the aeration tank 1 and agitated and aerated by the agitation type aerator 2. Sometimes, actinomycetes in the inflowing sewage may grow to generate foam scum 7. The foamed scum 7 floats on the water surface, but the flow on the water surface of the aeration tank 1 stays in the corner where the flow is not smooth. Especially, in the vicinity of the stirring type aerator 5 from the corner outlet,
Stagnation of scum is remarkable because stall is likely to occur because the water surface is not smooth and backflow is likely to occur near the screw.

[0003]

In the above conventional aeration tank, therefore, scum is accumulated and the appearance of the aeration tank is deteriorated, pests are generated, and scum is mixed into the treated water to deteriorate the water quality. There were problems such as. An object of the present invention is to solve the problems of the conventional aeration tank and to provide an aeration tank capable of preventing the foam scum from staying by smoothing the flow on the water surface.

[0004]

In order to achieve the above object, the aeration tank of the present invention is a cylindrical horizontal type water tank having front and rear end plates provided with a central partition wall and a stirring type aerator to form a circulating water amount. In order to guide the flow of scum floating on the water surface in an aeration tank that performs biological treatment with activated sludge,
It is characterized in that arc-shaped guide plates are provided above and below the water surface in front of the mirror plates at the two corners.

In the aeration tank of the present invention having the above-mentioned structure, by providing the arc-shaped guide plate, it is possible to form a smooth flow on the water surface, prevent the scum from staying at the inside of the corner, and agitate the aerator. Can guide scum to the bottom.

In this case, if a sprinkler is provided on the water surface in the vicinity of the aerator, the scum gathers in this part, so that the scum can be crushed and eliminated.

In the aeration tank of the present invention having the above structure, the scum can be efficiently crushed by providing the sprinkler on the water surface near the aerator.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the aeration tank of the present invention will be described below with reference to the drawings. In the figure, reference numeral 1 is an aeration tank using a horizontal cylindrical water tank, and this aeration tank 1 is provided with end plates 12 provided with arc-shaped corner guide plates 3 at both ends of a cylindrical portion 11 having a required diameter and length. It is constructed so as to be in contact with each other and integrated, and sewage is allowed to flow into the aeration tank 1 through an inflow pipe 6.

A partition wall 5 is provided at the center of the cylindrical horizontal aeration tank 1 to form a circulation water channel 13 in the aeration tank 1 having a circular arc corner and a smooth water flow. One or more agitating aerators 2 are installed in the circulating water channel. The stirring aerator 2 is illustrated as a screw type mechanical aerator, but is not particularly limited thereto. The corner guide plate 3 provided in the corner portion of the aeration tank 1 is provided so as to project along the inner peripheral surface of the end plate 12.

In the conventional aeration tank, as shown in FIGS. 4 and 5, the aeration tank corner portion is close to a rectangle, so that a smooth flow cannot be obtained, and a reverse flow is likely to occur near the screw, and the corner outlet side and the stirring aerator It was easy for scum 7 to accumulate in the vicinity, but by making the aeration tank 1 have an arc-shaped corner, the water flow at the corner, especially at the corner, is guided.
Dead water can be eliminated.

As means for making the corners of the aeration tank 1 into an arc shape, the guide plate 3 is made into an arc shape centered on the position of the central partition wall 5, preferably a semicircle, and a few c on the water surface.
It is installed so that it will be submerged by at least 10 cm or more under the water surface. At this time, the center of the arc does not necessarily have to be located on the central partition wall, but it is desirable to provide it on the central partition wall, particularly at the end portion of the partition plate in order to create a smooth flow. Further, in order to prevent the foam scum from entering the inner part of the guide plate 3, a bottom plate 31 is provided between the guide plate 3 and the end plate 12.
In addition to the above, a plate 32 is also provided in the gap between the guide plate 3 and the water tank cylindrical portion 11 at the corner inlet and outlet to prevent the scum from entering.

[0012] In this way, there is a basin-shaped space between the guide plate 3, the bottom plate 31, the plate 32, and the tank body.
In order to prevent sewage and sludge from entering this space, it is desirable to provide a lid on the top or fill the inside with a filler.

Therefore, it is possible to project the inner wall having the function of such a guide plate at the water surface position of the end plate and integrate it with the end plate, but it is also possible to provide such a guide plate separately from the end plate. And in that case, the bottom plate 31 and the plate 3
A simple structure in which 2 is omitted may be used.

With such a guide plate 3, inside the circulation channel,
In particular, a smooth water flow is formed at the corners to prevent the scum 7 from accumulating and accumulating, the sprinkler 4 is provided on the water surface near the aerator, and the scum accumulated near the aerator is crushed by the spray pressure. Although the sprinkler 4 is configured to sprinkle the sludge mixed liquid in the tank by providing the header pipe 42 having the nozzle 43 in the pump 41 via the pipe, the sprinkler 4 is not limited to this, and the treated water or the It is also possible to sprinkle fresh water such as water.

[0015]

According to the aeration tank of the present invention, the corners of the aeration tank are arcuate to smooth the water flow,
By eliminating dead water, scum accumulation can be suppressed.

Further, according to the aeration tank of the second aspect of the present invention, the sprinkler provided near the screw effectively scatters scum generated in the aeration tank and floating on the water surface by this water spray pressure. it can.

[Brief description of the drawings]

FIG. 1 is a plan view showing a first embodiment of an aeration tank of the present invention.

FIG. 2 is a vertical sectional front view of the same.

FIG. 3 is a vertical sectional side view of the same.

FIG. 4 is a plan view of a conventional aeration tank.

FIG. 5 is a vertical sectional front view of the same.

[Explanation of symbols]

 1 Aeration tank 11 Cylindrical part 12 End plate 2 Stirring type aerator 3 Guide plate 31 Bottom plate 32 Plate 4 Sprinkler 41 Pumping pump 42 Header pipe 43 Nozzle 5 Central partition wall 6 Inflow pipe 7 Scum

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Teruhisa Yoshida 3-11-1, Shimozakabe, Amagasaki City, Hyogo Prefecture Hitachi Kiden Kogyo Co., Ltd.

Claims (2)

[Claims] 1. A cylindrical horizontal tank having front and rear end plates,
In order to guide the flow of scum floating on the water surface, in the aeration tank where a central partition wall and a stirring type aerator are installed to form a circulating water channel to perform biological treatment with activated sludge, end plate of two corners are installed. An aeration tank with arcuate guide plates provided above and below the front water surface. 2. The aeration tank according to claim 1, wherein a watering device is provided on the water surface near the screw of the aerator.