JPH0728957Y2 - Air lift pump flow control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an air lift pump for a sewage purification tank, and more particularly to an improvement of a flow rate adjusting device of an air lift pump for advancing sewage.

[Conventional technology]

Usually, small-scale combined septic tanks for household use are combined with various separation tanks such as a sedimentation separation tank that precipitates sewage or an anaerobic treatment tank that treats sewage with anaerobic microorganisms, and an aerobic treatment tank that treats with aerobic microorganisms. In that case, there is a circulating filter tank type equipped with an air lift pump for circulating the sewage in the sewage purification tank. This air lift pump pumps sewage into the target sewage treatment tank by the force of the air supplied into the pumping pipe, but conventionally the sewage is adjusted by adjusting the amount of circulating water. Was adjusted, or it was adjusted by overflowing with a weighing box.

[Problems of conventional technology]

However, in the conventional method, it is difficult to finely adjust the circulating water amount, and an excessive amount of water may flow. Due to this excessive water amount, denitrification of the anaerobic filter tank at the advancing destination becomes poor, and solid matter easily flows out. There was a flaw.

[Problems to be solved by the device]

In view of the above problems, the present invention has been made for the purpose of providing a flow rate adjusting device capable of effectively adjusting the amount of water advected by an air lift pump to prevent the generation of an excessive amount of water.

[Technology for solving problems]

That is, the air lift pump flow rate adjusting device of the present invention is
An air lift pump for advancing sewage over a sewage treatment tank provided inside a sewage treatment tank, and a pumping pipe provided with the top exposed above the water level in the sewage treatment tank in the sewage treatment tank, A flow rate adjustment box attached to the top of the pumping pipe, and a horizontal pipe arranged from this box to the sewage treatment tank of the advection destination, having a sewage inlet or outlet in the flow rate adjustment box, An opening / closing plate having a sewage passage hole having a smaller diameter than the pumping pipe and the horizontal pipe is attached, and a water amount control plate for adjusting the opening degree of the sewage passage hole is provided.

〔Example〕

 Next, an embodiment of this invention will be described.

1 is a sectional view of an embodiment of the present invention, FIG. 2 is an enlarged perspective view of the embodiment, FIG. 3 is a sectional view of FIG. 2, and FIGS. 4A and 4B are plan views of FIG. is there.

The air lift pump 1 of this invention is used, for example, in a circulating filter bed type small combined septic tank 2 as shown in FIG. Anaerobic filter bed first chamber 2A and anaerobic filter tank second chamber 2B for treatment with anaerobic microorganisms, contact aeration tank 2C for treatment with aerobic microorganisms, and sedimentation tank for finally precipitating suspended sludge 2D and a disinfecting tank 2E for disinfecting the discharged liquid, the contact aeration tank 2C is equipped with an air lift pump 1, and the pump 1 disposes of sewage treated in the contact aeration tank 2C. By advancing to room 2A, sewage is circulated in the small combined septic tank.

The air lift pump 1 includes a pumping pipe 1a provided with its top exposed above the water level in the contact aeration tank 2C, a flow rate adjusting box 3 attached to the top of this pumping pipe 1a, and this box 3 Kara Anaerobic Floor Tank 1st Room
It has a horizontal pipe 1b arranged toward 2A, and at the wastewater inlet (or outlet) of the flow rate adjustment box 3,
An opening / closing plate 5 having a sewage passage hole 4 having a diameter smaller than that of the pumping pump 1a is attached by a hinge 6, and a water amount limiting plate 7 for adjusting the opening degree of the sewage passage hole 4 is rotatably provided. A valve 9 for sending air into the pipe 1a via the pipe 8 is provided.

[Action]

According to the structure described above, during normal sewage circulation, the opening / closing plate 5 is closed and the pumped sewage is caused to flow into the flow rate adjustment box 3 through the sewage passage hole 4. The amount of water flowing through the pipe 1b is limited to prevent the amount of water from becoming excessive, and from this state, the opening of the wastewater passage hole 4 is adjusted by the water amount limiting plate 7 as shown in FIG. It can be fine-tuned to a proper one. In addition, when the sludge is transferred in a short time after backwashing, a large amount of it can be transferred by opening the opening / closing plate 5, and the transfer in the short time can be easily performed.

Since the conventional adjustment using the measuring box was to overflow the dirty water to obtain the circulating water amount, the amount returned to the contact aeration tank 2C due to the overflow wasted in energy, and the amount of supply air for pumping water was also increased. Although much was required, in this invention, all the wastewater fried in the flow rate adjustment box 3 is advected, so there is no waste of energy,
It requires less air supply. Therefore, when one air blower is used for both air lift and air diffuser, the amount of air for air lift should be minimized and a large amount of air should be distributed for air diffuser to efficiently perform the nitrification action in contact aeration and denitrification. The nitrification method can prevent a decrease in nitrogen removal rate due to nitrification rate control.

〔effect〕

As described above, according to the present invention, the flow rate adjusting box at the top of the pumping pipe is provided with the two water amount adjusting functions of the opening / closing plate and the water amount adjusting plate, so that the advection water amount is prevented while the advection of the excessive water amount is prevented. The fine adjustment can be easily performed, and the sludge can be transferred for a short time after backwashing, and the amount of air for air lift used can be suppressed, and the dispersed air effect can be improved.

[Brief description of drawings]

1 is a sectional view of an embodiment of the present invention, FIG. 2 is an enlarged perspective view of the embodiment, FIG. 3 is a sectional view of FIG. 2, and FIGS. 4A and 4B are plan views of FIG. is there.

Front page continuation (72) Inventor Dai Harada, 1 Takamatsu, Kosai-cho, Koga-gun, Shiga Prefecture, 1 Kubota Shiga Factory (72) Inventor, Kazuyuki Honda 1-Kuma, Kosai-cho, Koga, Shiga 1 Kubota Corporation Inside the Shiga factory

Claims (1)

[Scope of utility model registration request] 1. An air lift pump for advancing sewage over a sewage treatment tank provided inside a sewage treatment tank, wherein the top is exposed above the water level in the sewage treatment tank. Pumping pipe, a flow rate adjusting box attached to the top of the pumping pipe, and a horizontal pipe arranged from this box to the sewage treatment tank at the advection destination. Alternatively, an opening / closing plate having a sewage passage hole having a diameter smaller than that of the pumping pipe and the horizontal pipe is attached to the outlet, and a water amount control plate for adjusting the opening degree of the sewage passage hole is provided. Flow control device for air lift pump.