JPS6234562Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Application of the Invention) The present invention relates to a supernatant liquid discharge device, and more specifically to a supernatant liquid discharge device used in an activated sludge device or the like.

(Prior art) Activated sludge equipment has the following steps: raw water inflow, aeration, precipitation, and supernatant liquid discharge. Among these, the supernatant liquid discharge process quickly and reliably drains the separated upper layer of water to the outside. Furthermore, it is required that no liquid flows out except during the supernatant liquid discharge process.

Conventional supernatant liquid discharge mechanisms include those that provide a weir (opening) on the side of the liquid tank where the supernatant liquid is located and discharge the liquid by overflowing, or install an overflow arm to a movable joint to remove the overflow. One example is one in which the supernatant liquid is discharged by mechanically moving the arm up and down.

(Problems to be solved by the invention) However, in such conventional technology, in order to prevent scum from being mixed into the supernatant liquid, it is necessary to provide a scum inflow prevention plate (batsful). In addition, there was a drawback that there was a limit to the amount of water that could be treated in the case of overflow.

The purpose of the present invention is to eliminate the drawbacks of the above-mentioned conventional techniques and to provide a supernatant liquid discharge mechanism that can quickly discharge a large amount of liquid without mixing scum etc. into the supernatant liquid. .

(Means for Solving the Problems) The present invention comprises a buoyancy chamber connected to an air supply and discharge means, a vertical supernatant liquid discharge pipe integrally provided with the buoyancy chamber, and a It has a siphon pipe connected to the upper part of the pipe, and a siphon break means provided on the siphon pipe, and the lower end of the liquid discharge pipe is connected to a retractable pipe fixed to the lower part of the liquid tank. It is characterized by

Hereinafter, the present invention will be explained in more detail with reference to embodiments shown in the drawings.

(Example) FIG. 1 is a schematic sectional view of a supernatant liquid discharge mechanism showing an example of the present invention. This device includes a buoyancy chamber 3 connected to air supply and discharge means (pipe 17 and valve 19), an air chamber 5 provided in the upper part of the buoyancy chamber 3, and an integral part of the buoyancy chamber 3. A T-shaped (or octopus-shaped) supernatant liquid discharge pipe 7 provided;
It has a vertical siphon pipe 11 connected to both ends of the discharge pipe 7, and a siphon break means (pipe 13 and valve 15) provided on the supernatant liquid discharge pipe 7, and the liquid discharge pipe The lower end of 7 is connected to a telescopic tube 9 fixed to the lower part of the liquid tank 27.

The lower part of the buoyancy chamber 3 opens into the tank, and means for introducing and discharging the air into the buoyancy chamber 3 include a conduit 17 and a valve 19 whose one end opens into the buoyancy chamber.
and a pressurized air source (not shown) connected to the conduit 17. The volumes of the buoyancy chamber 3 and the air chamber 5 are such that when air is supplied, the siphon tube 11 is above the liquid level of the supernatant liquid 23 with its lower end immersed in the liquid (the state shown in Figure 4), and the air The design is such that the entire siphon tube 11 sinks below the liquid surface due to its own weight at the time of discharge (the state shown in FIG. 1). The siphon-on break means consists of a discharge pipe 7 communicating with the siphon pipe 11, provided with a conduit 13 and a valve 15 open to the atmosphere. The lower end of the siphon pipe 11 connected to the end of the discharge pipe 7 is adjusted to be below the liquid level 23 by a predetermined position so as to form a so-called submerged weir.

In the apparatus configured as described above, first, when preparing to discharge (collect) the supernatant, valves 15 and 19 are opened, and after the buoyancy chamber 11 is allowed to settle below the liquid surface by its own weight as shown in FIG. When you close the
At this time, liquid flows from the siphon pipe 11 into the discharge pipe 7 to form a siphon, and discharge of the liquid through the discharge pipe 7 and the telescopic pipe 9 is started.

Next, when the liquid level drops and reaches the state shown in Figure 2, valve 19 is closed as shown in Figure 3, and valve 1 is closed as shown in Figure 3.
Open 5 to break the siphon and discharge pipe 7.
Stop the flow of supernatant from. If necessary, such as when the break of the siphon is incomplete, the fourth
As shown in the figure, the valve 19 is opened (valve 15 remains open), air is supplied to the buoyancy chamber 3, the buoyancy chamber 3 is floated to a predetermined position, and the siphon can be completely turned off. Next, return to the initial operation (FIG. 1), and repeat the same operation to move the buoyancy chamber 3 up and down, and to suck in and discharge the supernatant liquid.

According to the above embodiment, since the siphon tube 11 forms a so-called submerged weir, suspended matter such as scum is not mixed into the supernatant liquid, and a clear liquid can be recovered. Furthermore, since the supernatant liquid is discharged using the siphon principle, a large amount of liquid can be discharged in one go without the need for special power.
Furthermore, by adjusting the position of the lower end of the siphon tube 11, the discharge level of the supernatant liquid can be easily adjusted.

(Effects of the invention) According to the invention, it is possible to obtain a clear supernatant liquid that does not contain floating substances such as scum without requiring a scum inflow prevention plate as in the conventional case, and because it uses a siphon tube. , a relatively large amount of supernatant liquid can be discharged.

[Brief explanation of the drawing]

FIG. 1, FIG. 2, FIG. 3, and FIG. 4 are explanatory views showing the operation of the supernatant liquid discharge device of the present invention, respectively. 1... Supernatant liquid discharge device, 3... Buoyancy chamber, 5...
Air chamber, 7... Supernatant liquid discharge pipe, 9... Telescopic pipe, 1
1... Siphon tube, 13, 17... Conduit, 1
5, 19...Valve, 23...Liquid level.

Claims (1)

[Scope of utility model registration request] A buoyancy chamber connected to an air supply and discharge means, a vertical supernatant liquid discharge pipe integrally provided in the buoyancy chamber, a siphon pipe connected to the upper part of the discharge pipe, and the siphon pipe. 1. A supernatant liquid discharge device, comprising: a siphon-on break means provided at the top of the liquid tank, and a lower end of the liquid discharge pipe is connected to a telescopic tube fixed to a lower part of the liquid tank.