JPH0518696U - Scum removal device for circular tank sedimentation tank - Google Patents

Abstract

(57) [Summary] [Objective] To provide a scum removing device capable of collecting all scum floating on the water surface and eliminating residual scum in a circular tank sedimentation basin. [Structure] On the radius connecting the inner circumference of the baffle plate 3 at the peripheral portion of the circular tank 1 and the outer circumference of the feed well 6 at the central portion,
Pipe skimmer 9 having an arcuate cross section and an opening 9a at the top
Is tiltably arranged, and the pipe skimmer 9 is tilted in synchronization with the rotation of the scum skimmer 5 and the feed well 6.
By opening and closing the opening 9a in water, the scum that is scraped by the scum skimmer 5 and circulates around the water surface is flowed into the pipe skimmer 9 and collected.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention mainly relates to a scum removing device in a circular tank sedimentation tank for water treatment.

[0002]

[Prior Art]

 In the circular tank sedimentation basin, in order to remove scum floating on the water surface, a scum skimmer is attached to the rotating shaft provided at the center in the radial direction, and the rotation causes the scum skimmer to move in the circumferential direction and the peripheral portion of the tank. A scum removal device was installed to collect scum through the scum mud collection box provided near the periphery due to the flow of scum in the radial direction accompanying the flow of water toward the overflow trough provided at Has been.

FIG. 5 shows a plan view of a conventionally known scum removing device for a circular tank sedimentation basin, and FIG. 2 shows a sectional view taken along line B-B thereof.

Reference numeral 1 denotes a circular tank in which a treated water overflow plate 2 and a scaffold outflow baffle plate 3 are concentrically arranged on the inner circumference of an outer edge portion thereof. Reference numeral 4 denotes a rotary shaft driven by a drive device (not shown), to which an inner end of a scum skimmer 5 is attached. 6 is a feed well for inflowing sewage, 7 is a trough on the outer periphery of the treated water overflow plate 2, and 8 is a scum recovery box.

Sewage is supplied into the feed well 6, and the supernatant liquid is discharged from the trough 7 as treated water through the treated water overflow plate 2 to the outside of the tank. On the other hand, the scum in the sewage floats near the water surface, but is prevented from flowing out of the tank by the baffle plate 3 for preventing the outflow of scum and floats in the tank.

The scum floating near the water surface in the tank is scraped in the circumferential direction by the scum skimmer 5 rotating with the rotating shaft 4 and heads for the overflow trough 2 provided at the peripheral edge of the circular tank 1. Along with the flow of water, it flows in a radial direction and is collected in a scum collection box 8 provided near the periphery.

However, even if the scum is scraped into the scum collection box 8, since the scum does not have fluidity, a considerable amount of water must be supplied as driving water to move the scum out of the tank. There is a problem.

In order to solve this problem, it has been proposed to make the scum collection box 8 up and down freely, or to make it a trough shape that rotates around a horizontal axis so that water near the water surface can flow in together with the scum. (See Japanese Utility Model Laid-Open No. 3-7996)

However, even if the water is introduced into the scum recovery box 8 together with the scum in this way, the recovery rate of the scum does not actually improve beyond a certain limit, and the scum recovery rate always remains in the tank. Then, it was found that there is a scum that continues to float without being discharged.

Therefore, as a result of various investigations by the inventors on the behavior of the scum in the circular tank 1, the circumferential flow of the scum floating near the water surface is an active flow due to the scraping of the scum skimmer 5. Since the radial flow is a negative flow that accompanies the flow of water, most of the scum and the scum skimmer 5 co-rotate on the water surface in the tank in the circumferential direction to circulate the donut-shaped water channel, resulting in the peripheral edge. It was discovered that the amount of scum discharged to the nearby scum collection box 8 was small, and most of the scum remained floating on the water surface in the circular tank 1.

[0011]

[Problems to be solved by the device]

 This device is a conventional scum removing device that consists of a scum skimmer attached to the rotating shaft and a scum recovery box installed at the peripheral edge, and the scum floating on the water surface in the tank rotates together with the scum skimmer to form a donut shape. Since it goes around the water channel, the whole amount of it cannot be collected in the scum collection box, and the problem is that the mud collection efficiency is very small.The problem is to solve all the scum floating on the water surface. The aim is to provide a scum removal device that can collect and eliminate residual scum.

[0012]

[Means for Solving the Problems]

 The present invention provides means for solving the above-mentioned problems, in which a treated water overflow plate 2 and a scum outflow preventing baffle plate 3 are concentrically arranged on the inner circumference of an outer edge portion of a circular tank 1. In a circular tank sedimentation basin equipped with a feed well 6 that rotates integrally with a rotating shaft 4 for driving a scum skimmer 5 in a central portion, a cross section is formed on a radius connecting an inner circumference of the baffle plate 3 and an outer circumference of the feed well 6. A pipe skimmer 9 having an arcuate shape and having an opening 9a in the upper part is tiltably arranged, and two kickers 13 and 14 are provided on the outer periphery of the feed well 6 so as to be displaced forward and backward and vertically, and Two engagement levers 15 and 16 are provided on the outer circumference of the inner end of the pipe skimmer 9 so as to be out of phase with each other, and a kicker 13 in front of the feedwell 6 in the rotational direction pushes one lever 15. The pipe skimmer 9 tilts, and the kicker 14 on the rear side in the rotation direction pushes the other lever 16 to return the pipe skimmer 9 to the original position. The device is the main idea.

[0013]

【Example】

 1 to 4 show an embodiment of the present invention. 1 is an overall plan view, FIG. 2 is an A-A sectional arrow view of FIG. 1, FIG. 3 is an enlarged plan view of a central portion, and FIG. 4 is a C-C sectional arrow view of FIG.

Reference numeral 1 is a circular tank, and a treated water overflow plate 2 and a scaffold baffle plate 3 for preventing scum outflow are concentrically arranged on the inner periphery of the outer edge portion thereof. A rotating shaft 4 is driven by a driving device (not shown), and an inner end of a scum skimmer 5 having a scum scraping plate 11 hanging down is attached thereto. Reference numeral 6 denotes a feed well which rotates integrally with the rotary shaft 4, and 7 denotes a treated water outflow trough provided on the outer periphery of the treated water overflow plate 2. The above is the same as the conventional example shown in FIG. 5, but instead of the scum recovery box 8 which is conventionally provided near the peripheral portion, a radial pipe skimmer 9 described later is provided.

Reference numeral 9 denotes a pipe skimmer having an arcuate cross-section having an opening 9a at an upper portion thereof, which is mounted on a fixed frame 10 installed on a radius connecting the inner circumference of the baffle plate 3 and the outer circumference of the feed well 6. The bearing 12 is arranged so as to be tiltable.

On the outer circumference of the feed well 6, two kickers 13 and 14 are provided so as to be displaced in the front-rear direction and the vertical direction, while the kicker is provided on the outer circumference of the inner end portion of the pipe skimmer 9. Two levers 15 and 16 corresponding to 13 and 14 are provided so as to be out of phase with each other. The kickers 13 and 14 do not have to be directly attached to the outer peripheral wall surface of the feed well 6, but may be attached to the rotating shaft 4 or a member integrated with the rotating shaft 4 so as to project outward from the outer periphery of the feed well 6. Good.

As for the positional relationship between the kickers 13 and 14 and the levers 15 and 16, as shown in FIG. 4, the opening kicker 13 located on the lower front side in the rotational direction of the feed well 6 is located below the pipe skimer 9. When the opening lever 15 is pushed away, the pipe skimmer 9 tilts as shown by the chain double-dashed line so that the upper opening 9a opens in the water, and the closing kicker 14 also located in the upper rear part in the rotational direction is above the pipe skimmer 9. By pushing away the closing lever 16 located at, the pipe skimmer 9 returns to the original position shown by the solid line.

[0018]

[Action]

 As the rotating shaft 4 rotates, the scum skimmer 5 having the scraping plate 11 and the feed well 6 rotate in synchronization. When the opening kicker 13 at the lower front in the rotation direction, which is provided on the outer periphery of the feedwell 6, comes into contact with the opening lever 15 of the pipe skimmer 9 and pushes the lever 15 away, the pipe skimmer 9 moves clockwise in FIG. The upper opening 9a rotates and opens in water. The kicker 13 pushes the lever 15 away and passes by, and the lever 15 takes the position shown by the chain double-dashed line.

Next, when the closing kicker 14 at the upper rear in the rotational direction, which is provided on the outer periphery of the feedwell 6, contacts the closing lever 16 of the pipe skimmer 9 and pushes the lever 16 away, the pipe skimmer 4 rotates counterclockwise in FIG. 4 to return to the original position, the upper opening 9a opens in the air, and the underwater opening closes. The kicker 14 pushes the lever 16 away and passes by, and the lever 16 returns to the position shown by the solid line.

In this way, the feed skeleton 6 that rotates integrally with the rotary shaft 4 at the center of the circular tank 1 causes the pipe skimmer 9 to tilt and open its upper opening 9a into the water, or The opening can be closed.

The pipe skimmer 9 is arranged on the radius connecting the inner circumference of the baffle plate 3 located at the outer edge of the circular tank 1 and the outer circumference of the feed well 6 at the center, in other words, Since it is installed in a direction that traverses the donut-shaped water channel, it is possible to efficiently collect scum that is scraped by the scraping plate 11 of the scum skimmer 5 and circulates in the circumferential direction.

Further, since the scum skimmer 5 provided with the scraping plate 11 and the feed well 6 both rotate at the same number of rotations as the rotation shaft 4, the protrusion positions of the kickers 13 and 14 on the outer periphery of the feed well 6 are appropriate. By selecting the, the turning of the scum skimmer 5 and the tilting of the pipe skimmer 9 can be easily synchronized.

[0023]

[Effect of the device]

 According to the present invention, a pipe skimmer 9 having an arcuate cross section and an opening 9a at the upper portion is tiltably disposed on the radius connecting the inner circumference of the baffle plate 3 and the outer circumference of the feed well 6, and the scum skimmer 5 Also, since the pipe skimmer 9 can be tilted in synchronization with the rotation of the feed well 6 and the opening 9a can be opened and closed in water, all the scum that is scraped by the scum skimmer 5 and floats around the water surface. There is an effect that can be collected.

[Brief description of drawings]

FIG. 1 is an overall plan view showing an embodiment of the present invention.

2 is a sectional view taken along the line AA of FIG.

FIG. 3 is an enlarged plan view of a central portion.

4 is a cross-sectional view taken along line CC of FIG.

FIG. 5 is a plan view showing a conventional example.

6 is a cross-sectional view taken along the line BB of FIG.

[Explanation of symbols]

 1 circular tank 2 treated water overflow plate 3 baffle plate for preventing scum outflow 4 rotating shaft 5 scum skimmer 6 feedwell 7 trough 8 scum box (conventional example) 9 pipe skimmer 9a upper opening of pipe skeleton 11 mount 11 scum rake plate 12 Bearing 13 Kicker (for opening) 14 Kicker (for closing) 15 Lever (for opening) 16 Lever (for closing)

Claims (1)

[Scope of utility model registration request] 1. A circular tank (1) is concentrically provided with a treated water overflow plate (2) and a baffle plate (3) for preventing scum outflow on the inner periphery of a peripheral part, and for driving a scum skimmer (5) in the center. In a circular tank sedimentation basin equipped with a feed well (6) that rotates integrally with the rotating shaft (4) of the above, on the radius connecting the inner circumference of the baffle plate (3) and the outer circumference of the feed well (6), Pipe skimmer (9) with an arcuate section and an opening (9a) at the top
Is tiltably arranged, and the two kickers (13), (1
4) and two engaging levers (15) and (16) projecting on the outer circumference of the inner end of the pipe skimmer (9) with a phase shift, and the direction of rotation of the feedwell (6). Front kicker (1
3) pushes the lever (15) on one side
A circular tank sedimentation basin characterized in that the pipe skimmer (9) is returned to its original position by tilting the (9) and pushing the other lever (16) by the kicker (14) at the rear of the rotation direction as well. Scum removal device.