JPH07121326B2 - Sludge collecting and discharging device for sedimentation pond - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sludge collecting and discharging device for collecting and discharging sludge accumulated in a sedimentation basin.

[0002]

2. Description of the Related Art Conventionally, as one of the methods for discharging sludge settled on the inner bottom of a sedimentation basin, a perforated pipe is horizontally arranged at the inner bottom of the sedimentation basin, and one end of the perforated pipe is led out of the sedimentation basin. It is known to interpose a discharge valve at the end and open this valve intermittently to discharge the sludge that has settled by using a water pressure proportional to the water depth of the settling basin.

As another example, a horizontal mud collecting pipe is provided in the vicinity of the inner bottom of a sedimentation basin, and the horizontal mud collecting pipe has a large number of branch pipes hanging down and the upper ends of the branch pipes penetrating up to near the inner upper part of the horizontal mud collecting pipe. In addition, the air supply and exhaust pipe and the sludge pipe are connected to each other, and an exhaust valve is provided at the upper end of the air supply and exhaust pipe, and a pressure air supply pipe with a valve below the exhaust valve is connected to the sludge collection pipe. An ejector is proposed by Japanese Patent Publication No. 55-38166.

[0004]

However, in the case of the first example described above, when the valve is used, sludge is discharged from the hole on the side of the perforated pipe close to the valve, and almost no sludge is discharged from the hole on the far side. However, it is not practical because it is not discharged.

The second example according to the patent publication is excellent in principle, but actually only collects mud in the vicinity of a large number of branch pipes. Must be provided at a narrow pitch, which is extremely disadvantageous in terms of economical cost.

In view of the problems of the above-mentioned conventional sludge collecting and discharging device, the present invention is installed in a sedimentation basin of a plurality of mud collecting pipes in an economical range and sends pressurized air from an air source to the sludge collecting pipe to discharge the sludge collecting pipe. A sludge collecting and discharging device that can continuously and evenly collect sludge on the entire area of the sedimentation basin by utilizing the fact that the pipe pressure drops to atmospheric pressure at the moment all sludge is discharged from the The challenge is to provide.

[0007]

As a means for solving the above problems, the present invention provides a plurality of sets of horizontal mud collecting pipes having a plurality of branch pipes penetrating to the vicinity of the upper part of the pipe with both ends closed at predetermined intervals. The air supply pipes are connected to the connecting pipes that are connected across the horizontal mud collecting pipes, and the other connecting pipe is set lower than the horizontal mud collecting pipes. Set the length so that the lower ends of the branch pipes are close to the bottom of the sedimentation basin and the upper ends of the air supply pipe and the sludge drainage pipe are above the liquid level of the sedimentation basin, and The sludge collecting and discharging device for the sedimentation basin was constructed by installing a pressure water injection pipe in the zone between the branch pipes.

[0008]

In the sludge collecting / discharging device of the present invention having the above-mentioned structure, when the blower is connected to the air supply pipe as an air source and pressurized air is sent in, the sludge collecting pipe inside the sludge collecting pipe is discharged at the moment when the sludge is discharged. Pressure drops to atmospheric pressure. Therefore, the sludge flows into the mud collection pipe from the branch branch pipe by the hydrostatic pressure of the sewage in the sedimentation pond, and the mud is collected.

The sludge that has flowed into the mud collection pipe is then pushed toward the mud pipe by the pressure air gradually fed from the blower and discharged. When all the mud is discharged, the pressure inside the mud collection pipe is lowered to atmospheric pressure again, and the mud is collected and this is repeated intermittently.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an external perspective view of an example in which the sludge collecting and discharging device of the embodiment is installed in a sedimentation basin. Reference numeral 1 is a sedimentation pond, and 2 is a mud collecting pipe arranged at the inner bottom of the sedimentation pond. A large number of branch pipes 3 branch and hang down over the entire length of the mud collecting pipe 2, and the upper end of the branch pipe 3 penetrates to the inner upper portion of the horizontal mud collecting pipe 2 as shown in FIG. 2 (b). It is raised, and the lower end is formed as a T-shaped branched branch pipe 3a.

As shown in the figure, a large number of mud collecting pipes 2 are arranged side by side within a settling basin 1 at predetermined intervals. Each mud pipe 2
Are closed at both ends, and two connecting pipes 4 and 5 are connected in a direction orthogonal to the mud collecting pipes 2 across them.
Is provided.

An end of the one connecting pipe 4 is connected to an air supply pipe 6, and an upper end of the connecting pipe 4 is connected to a blower 7 as a pressure air source. 8 is connected. The lengths of both the air supply pipe 6 and the sludge discharge pipe 8 are set so as to extend above the liquid surface of the sedimentation tank 1. Further, the upper end of the sludge discharge pipe 8 is open to the atmosphere so that the sludge can be discharged into a gutter 9 provided on the side of the sedimentation basin.

Between the branch pipe 3 of the mud collecting pipe 2 and the branch branch pipes 3a and 3a of the branch pipes 3 of the mud collecting pipe 2 adjacent to the mud collecting pipe 2, as shown in FIG. A pressure water jet pipe 10 is provided in parallel with. The pressure water injection pipe 10 is provided with a large number of injection holes 10a at appropriate intervals along its length, and pressure water is injected from these injection holes 10a to mix and fluidize sludge in the wastewater. In the illustrated example, the ends of the branch branch pipes 3a are arranged in a grid pattern when viewed from just above the sedimentation basin, and are provided at a pitch of, for example, 500 mm.

A plurality of the above-mentioned pressure water jet pipes 10 are also provided, and a connecting pipe 11 is connected across these pipes, and although not shown in the figure, pressure water is sent by a pressure water pump connected to the end thereof. It is provided.

The operation of the sludge collecting / discharging device of this embodiment having the above structure will be described with reference to FIG.

FIG. 4A shows a state in which the mud collecting pipe 2 is filled with air and the apparatus is stopped while maintaining equilibrium. Although not shown in the drawing, a check valve is provided at the pressure air discharge port of the blower 7, and it is assumed that the pressure balance will not be lost and sewage will not flow back to the blower 7.

(B) shows a mud collecting state. When the blower 7 was started to collect mud and pressurized air was further sent from the state of (a) by the blower 7, the sludge remaining in the sludge pipe 8 was completely discharged to the gutter 9, and thus was discharged. At the moment, the pressure in the mud collection pipe 2 drops to atmospheric pressure.

When the pressure inside the mud collecting pipe 2 drops to atmospheric pressure, the branch pipe 3
Since the water pressure of the settling basin always acts as a static pressure on the tip of the branching branch pipe 3a, the static pressure causes the sludge to flow into the mud collecting pipe 2, and the air supply pipe 6 and the drain mud pipe 8 also. It is filled and sludge is collected to the liquid level.

At this time, since the mud collecting action in the mud collecting pipes 2 is performed by the hydrostatic pressure of the sewage as described above, the water pressure is evenly applied to the branch pipes 3 of the respective mud collecting pipes 2, so that the sedimentation occurs. The mud can be collected evenly over the entire pond.

Further, a pressure water injection pipe 10 is laid between the adjacent mud collection pipes 2 and the respective branch branch pipes 3a and 3a of the mud collection pipes 2, and the pressure water is injected from a large number of the injection holes 10a. Is jetted. Therefore, even if the branch branch pipes 3a and 3a are provided slightly apart from each other, sludge can be removed by injecting pressure water into a dead zone formed between the range in which each branch branch pipe 3a can be sucked. By mixing and increasing the fluidity, sludge in the entire range can be easily sucked from the branch branch pipe 3a.

(C) shows the sludge removal action. When the sludge is collected up to the state of (b), the blower 7 constantly sends pressurized air, so the sludge in the air supply pipe 6 and the sludge collection pipe 2 is gradually pushed by the pressurized air by the blower 7 and the sludge is discharged. Tube 8
Emitted from.

In this case, since the branch pipe 3 has penetrated to the upper part of the mud collecting pipe 2 and has been started up, the sludge does not return to the branch pipe 3 and the connecting pipe 5 connected to the mud collecting pipe 2 Sludge pipe 8
The sludge is sent out.

In this way, when the sludge discharging action progresses and all the sludge in the discharging sludge pipe 8 is discharged, the state returns to the state of (b) and the sludge collecting action is performed again. Therefore, by continuously operating the blower 7, it is possible to intermittently repeat the above-mentioned mud collecting and mud discharging operations to perform the mud collecting and discharging operation by automatic operation.

[0024]

As described above in detail, in the sludge collecting and discharging device of the present invention, a plurality of mud collecting pipes are arranged in parallel, and pressure air is sent from these air supply pipes to the mud collecting pipes so that pressure is applied at the moment when the mud collecting pipes become empty. Is reduced to atmospheric pressure, and then it is gradually discharged with pressurized air from the mud pipe, and a pressure water jet pipe is installed in the dead zone between the branch pipes. Since the sludge is fluidized by sending pressurized water to the sludge, an extremely simple, economical and reliable sludge collecting and discharging device capable of collecting and discharging the sludge uniformly over the entire range can be obtained.

[Brief description of drawings]

FIG. 1 is an external perspective view of the sludge collection and discharge device of the embodiment installed in a sedimentation basin.

FIG. 2 is a sectional view of the same as above (including a partially enlarged sectional view).

FIG. 3 is a sectional view taken along the line III-III in FIG.

FIG. 4 is an explanatory diagram of operation

[Explanation of symbols]

 1 Sedimentation basin 2 Horizontal mud collection pipe 3 Branch pipe 3a Branch branch pipe 4, 5 Connection pipe 6 Air supply pipe 7 Blower 8 Drain pipe 9 Side groove 10 Pressure water injection pipe 10a Injection hole 11 Connection pipe

Claims (1)

[Claims] 1. A plurality of sets of horizontal mud collection pipes, in which a plurality of branch pipes are branched and hung so that they can penetrate up to the vicinity of the upper part of the pipe with both ends closed, are arranged in parallel at a predetermined interval, and are connected across these horizontal mud collection pipes. Connect the air supply pipe to the connecting pipe and the other connecting pipe to a position lower than the horizontal mud collecting pipe, and connect the drain mud pipe to this to stand up, and supply the air with the lower end of the branch branch pipe close to the bottom of the sedimentation basin. The length is set so that the upper ends of the pipes and the sludge discharge pipe are above the liquid level of the sedimentation basin, and a pressure water injection pipe is installed in the zone between the branch pipes of the adjacent horizontal mud collection pipes. Sludge collection and discharge device for sedimentation basins.