JP2000334216A - Flight for sludge raking machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flight for sludge raking machine by which adequate down load is applied on the flight in sewage at all times by easily adjusting the down load. SOLUTION: This flights 4 for sludge raking machine are fitted to an endless chain stretched movably along the bottom of a sewage treating tank at prescribed intervals to rake the sludge precipitated on the bottom of the sewage treating tank. The flight 4 is made from corrosion resistance steel so that a buoyancy generating material 42 is inserted into the hollow inside of the flight main body 41 having a hollow structure on its inside to adjust the buoyancy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flight of a sludge scraper (including a sludge scraper, and is simply referred to as "sludge scraper" in the present specification), and more particularly to a flight in sludge. The present invention relates to a flight of a sludge scraper in which a downward load applied to a flight can be easily adjusted by sewage characteristics to always obtain an appropriate downward load.

[0002]

2. Description of the Related Art A sludge scraper in a sewage treatment tank (including a sedimentation basin, a sludge sedimentation basin, a sewage treatment basin, etc., and is simply referred to as a "sewage treatment tank" in the present specification) is used in a sewage treatment plant.
Generally, as shown in FIG. 3, an endless chain 3 that moves along a tank bottom 11 of a sewage treatment tank 1 is provided in a sewage treatment tank 1 having a sludge pit 12 for collecting and temporarily storing sludge settled at one end. And a flight 4 is attached to the endless chain 3 at a predetermined interval.
By driving a motor M, the sludge settled on the tank bottom 11 of the sewage treatment tank 1 by the flight 4 moving along the tank bottom 11 of the sewage treatment tank 1 is scraped into the sludge pit 12 to collect sludge. Then, the collected sludge is discharged from the sewage treatment tank 1 through the sludge extraction pipe 2, and the scum floating on the water surface is raked by the flight 4 located at the water surface position on the return side. Sewage treatment tank 1
To be discharged from

[0003]

In the conventional sludge scraper, the endless chain 3 is driven by a motor M, so that the flight 4 moves along the bottom 11 of the sewage treatment tank 1 to treat the sewage. Due to the structure that scrapes the sludge settled on the tank bottom 11 of the tank 1, the flight 4 is not corroded by sewage or sludge, and is worn by contact with the tank bottom 11 or the guide rail 13 laid on the tank bottom 11. The flight 4 may be made of wood, synthetic wood, or synthetic resin, or may be made of corrosion-resistant steel such as stainless steel having a hollow structure capable of sealing the inside so as to generate an appropriate buoyancy. It was made with square pipes.

By the way, the properties of sewage and sludge are not fixed by the sewage treatment tank 1, and therefore, the interval between flights and the unit length and weight of the endless chain are reduced.
Despite being different for each, flight 4 made of conventional wood, synthetic wood, or synthetic resin, or made of square pipe made of corrosion-resistant steel such as stainless steel,
The buoyancy was determined at the time of manufacture, and there was a problem that it was difficult to adjust the sludge to apply an appropriate downward load.

[0005] Furthermore, a flight made of a corrosion-resistant steel square pipe has a problem that if pitting occurs in the corrosion-resistant steel and a pinhole is formed, sewage enters the inside and buoyancy cannot be obtained. there were.

The present invention has been made in view of the above-mentioned problems of the conventional sludge scraper flight, and makes it possible to easily adjust the downward load applied to a flight in sewage so that an appropriate downward load is always applied to the flight. In this way, the sludge scraper that has been able to reliably scrape the settled sludge, reduce the wear of the sliding part of the flight, and improve the durability. Intended to provide flights.

[0007]

In order to achieve the above object, a flight of the sludge scraper of the present invention is provided at predetermined intervals on an endless chain stretched so as to move along the bottom of a sewage treatment tank. At the time of the sludge scraper flight to scrape the sludge settled on the bottom of the sewage treatment tank, the buoyancy generating material is inserted into the hollow inside of the flight body made of corrosion-resistant steel and has a hollow structure. It is characterized by being inserted so as to be adjustable.

In this case, the internal volume of the flight body into which the buoyancy generating material is inserted is defined as: the internal volume of the flight body (1—specific gravity of the buoyancy generating material) = fight own weight + (flight mounting interval × chain unit length weight) -As the relationship (1), the downward load of the flight can be adjusted.

The flight of this sludge scraper is made of corrosion-resistant steel, and the buoyancy generating material is inserted into the hollow interior of the flight body having a hollow interior, so that it is inserted into the hollow interior of the flight body. The resulting buoyancy can be adjusted by changing the size of the buoyancy generating material.

Further, the buoyancy generating material can be constituted by a closed-cell foamed resin material.

Thus, a buoyancy-generating material having a universal buoyancy can be easily obtained even if machining such as cutting is performed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a flight of a sludge scraper according to the present invention will be described with reference to the drawings.

[0013] Sludge scraper A to which the flight of the present invention is applied
As in the conventional sludge scraper, as shown in FIG. 3, a sludge pit 1 for collecting and temporarily storing sludge settled on one end.
Bottom 11 of sewage treatment tank 1 in sewage treatment tank 1 provided with
Endless chain 3 so that it moves along
At intervals W, it is hung over sprocket wheels 81, 82, 83, 84 arranged underwater and on water, and is stretched between endless chains 3. By mounting the endless chain 3 and driving the motor M, the flight 4 moving along the tank bottom 11 of the sewage treatment tank 1 causes the sludge settled on the tank bottom 11 of the sewage treatment tank 1 to enter the sludge pit 12. The sludge collected and collected, and the collected sludge is discharged from the sewage treatment tank 1 through the sludge withdrawal pipe 2, and the scum floating on the water surface is scraped by the flight 4 at the water surface position on the return side. The sewage treatment tank 1 is discharged from the sewage treatment tank 1 via a scum gap 6 installed at a water surface position near the center of the sewage treatment tank 1.

A plurality of outflow gutters 7 are installed at the water surface position behind the scum gap 6 in the sewage treatment tank 1 so that sludge is settled and separated, and scum-removed sewage is discharged from the sewage treatment tank 1. I have to.

In this case, the installation interval P of the flight 4 to be bridged between the two endless chains 3 of the sludge scraper A depends on the processing capacity of the sludge scraper A and the sewage flowing into the sewage treatment tank 1. And sludge properties.

The flight 4 is, as shown in FIGS.
A flight body 41 obtained by cutting a square pipe made of corrosion-resistant steel such as stainless steel having a predetermined width D and a height H into an appropriate length L according to the width of the sewage treatment tank 1;
1 and a lid 4 fixed to both ends of the flight main body 41 for preventing the buoyancy generating material 42 inserted into the hollow interior of the flight main body 41 from falling out.
3 and more configuration simplified by changing the magnitude of the buoyancy generating member 42 to be inserted into the hollow interior of the flight body 41, resulting buoyancy F _U, i.e., a downward load F _D exerted on the flight 4 in a sewage Can be adjusted.

The buoyancy generating material 42 is the sum of the weight of the flight body 41 and the lid 43 made of corrosion-resistant steel and the weight of the endless chains 3 and 3 per unit length (the mounting interval P of the flights 4). and a buoyancy F _U generated by 42, moderate downward load F _D is as applied to the flight 4,
Determine its size, etc. For this reason, the internal volume of the flight body into which the buoyancy generating material is inserted is defined as the internal volume of the flight body (1−specific gravity of the buoyancy generating material) = fight own weight + (flight mounting interval × chain unit length weight) (1) as the relation), a downward load F _D flight 4 to be able to moderate arbitrarily from 0.

The buoyancy generating material 42 is preferably made of a closed-cell foamed resin material, so that a buoyancy generating material having a universal buoyancy can be easily obtained even if machining such as cutting is performed. Thus, the downward load of the flight 4 can be gradually adjusted.

It should be noted that the buoyancy generating material 42 inserted into the hollow interior of the flight body 41 is prevented from falling out.
Since it is not necessary to seal the inside of the hollow of the cover 43 and the flight main body 41 fixed to both ends of the device 1, a simple structure may be used. For example, as shown in the figure, a metal plate made of corrosion-resistant steel is bent into an L shape in the same manner as the flight body 41, and one piece is screwed along the outer surface of the flight body 41, and the other piece is flighted. A part of the opening of the main body 41 may be closed. In this flight 4, even if a pinhole is formed in the flight body 41 due to pitting action, the buoyancy obtained by the buoyancy generating material 42 does not fluctuate, and the proper downward load F _{D is} always maintained.
Can take flight 4.

The operation of the sludge scraper will now be described. When the sewage flowing into the sewage treatment tank 1 flows downstream, gravity separation is performed, and the sludge is settled. At this time, since the thing with a large specific gravity settles quickly, the thing with a large specific gravity settles in the tank bottom 11 from the upstream to the downstream of the sewage treatment tank sequentially. By driving the motor M to drive the endless chain 3 of the sludge scraping device A, the sludge deposited on the tank bottom 11 of the sewage treatment tank 1 is removed by the flight 4 moving along the tank bottom 11 of the sewage treatment tank 1. The sludge collected and collected in the sludge pit 12 is discharged from the sewage treatment tank 1 through the sludge extraction pipe 2, and the flight 4 located at the water surface position on the return side.
Thus, the scum floating on the water surface is swept up and discharged from the sewage treatment tank 1 via the scum gap 6. On the other hand, sewage from which sludge and scum have been separated and removed is discharged from the outflow gutter 7. The driving of the sludge scraping device A can be performed continuously or intermittently by following the settling amount of the sludge. Can be.

The spacing between the flights 4 and the unit length and weight of the endless chain 3 are different for each sewage treatment tank 1 depending on the properties of the sewage and sludge flowing into the sewage treatment tank 1.
In accordance with this, by adjusting the buoyancy F _U generated by the buoyancy-generating material 42 in each flight 4, moderate downward load F _D is so applied to the flight 4. Accordingly, the settled sludge can be reliably scraped, and the wear of the sliding portion of the flight 4 can be reduced and the durability can be improved.

[0022] The adjustment of the buoyancy F _U generated by the buoyancy-generating material 42 in the flight 4, remove one of the lid 43 to be fixed to both ends of the flight body 41, buoyancy generating material 42 inserted in the hollow interior Is taken out and replaced with a buoyancy generating material 42 of an appropriate size, or a process such as cutting is performed on the buoyancy generating material 42,
And the buoyancy generating material 42
Is inserted into the hollow interior of the flight main body 41 and the lid 43 is closed, so that the operation can be easily performed. Further, it is desirable that the buoyancy generating material 42 is inserted into a position substantially at the center of the flight body 41 so as not to move.

[0023]

According to the flight of the sludge scraper of the present invention, the buoyancy generating material is inserted into the hollow interior of the flight body made of corrosion-resistant steel and having a hollow structure. The buoyancy obtained by changing the size of the buoyancy generating material inserted into the hollow interior of, namely,
The downward load applied to the flight in sewage can be easily adjusted so that an appropriate downward load is always applied to the flight, thereby ensuring that the settled sludge is raked, Wear of the sliding part of the flight can be reduced, and durability can be improved. In addition, in this flight, even if a pinhole is formed by pitting, the buoyancy obtained by the buoyancy generating material does not fluctuate, and an appropriate downward load can always be applied to the flight.

Further, by forming the buoyancy generating material from a closed-cell foamed resin material, a buoyancy generating material having a universal buoyancy can be easily obtained even if machining such as cutting is performed.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a flight of a sludge scraper according to the present invention, wherein (A) is a front view and (B) is a side view.

FIG. 2 is an explanatory diagram showing a relationship between an endless chain and a flight.

FIG. 3 shows the whole form of a sludge scraper, (A) is a plan view,
(B) is a sectional view.

FIG. 4 shows a conventional flight, (A) is a front view,
(B) is a side view.

[Explanation of symbols]

 A Sludge scraper 1 Sewage treatment tank 11 Tank bottom 3 Endless chain 4 Flight 41 Flight body 42 Buoyancy generating material 43 Lid

Claims (3)

[Claims] 1. An endless chain stretched to move along the bottom of a sewage treatment tank at predetermined intervals,
In the flight of a sludge scraper to scrape the sludge settled to the bottom of the sewage treatment tank, a buoyancy generating material is inserted into the hollow interior of the flight body made of corrosion-resistant steel and having a hollow interior.
A sludge scraper flight characterized by being inserted so that its buoyancy can be adjusted. 2. A flight body according to claim 1, wherein the internal volume of the flight body into which the buoyancy generating material is inserted is adjusted according to the following equation (1).
The sludge scraper flight described. Internal volume of the flight body (1-specific gravity of buoyancy generating material) = Flight's own weight + (Flight installation interval x Chain unit length weight) ... (1) 3. The flight of a sludge scraper according to claim 1, wherein the buoyancy generating material is made of a closed-cell foamed resin material.