PH12012000165A1

PH12012000165A1 - Sludge collector

Info

Publication number: PH12012000165A1
Application number: PH12012000165A
Authority: PH
Inventors: Chin Takayoshi; Kojima Takurou; Nose Kazuhiro; Otsuka Kanako
Original assignee: Tsukishima Kikai Co
Priority date: 2010-12-20
Filing date: 2012-06-15
Publication date: 2015-01-21
Also published as: PH12012000165B1; JP2012130837A; JP5743527B2

Abstract

A sludge collector includes a sludge collecting body 8 in which flights 7 collecting sludge accumulated on a bottom surface Q of a sludge settling pond P are attached to chains 6 which are arranged to wind endlessly and are rotationally driven in the sludge settling pond P. The sludge collecting body 8 is configured to float in treated water W inside the sludge settling pond P, and an upper rail 9A which restrains emerging of the sludge collecting body 8 and a chain tension area X where the upper rail 9A is not provided and which allows the emerging of the sludge body 8 in the treated water W are provided on a drive path of the sludge collecting body 8 of the upper side in the sludge settling pond P.

Description

:

SLUDGE COLLECTOR

BACKGROUND OF THE INVENTION Field of the Invention

[0001]

The present invention relates to a sludge collector which is provided in a sludge settling pond of a sewage treatment plant or the like and collects sludge accumulated in a pond bottom of the sludge settling pond.

[0002]

As such a collector, for example, devices are known which are disclosed in

Japanese Unexamined Patent Application Publication No. 2000-334216 and Japanese

Unexamined Patent Application Publication No. 2009-241022. The sludge collector is configured such that flights are attached at chains which are arranged to wind endlessly and rotationally driven inside the sludge settling pond, and the flights collect the sludge accumulated in the pond bottom of the sludge settling pond. The sludge collectors disclosed in the related art described above are configured such that the chains and the flights are sunk in the treated water inside the sludge settling pond by their own weight, shoes of the flights move while contacting with rails along the rails arranged on the bottom surface of the settling pond, and the sludge is collected.

[0003]

However, in such a sludge collector, since the flights move, due to the shoes moving while contacting the rails along the rails arranged on the bottom surface of the settling pond in which the sludge is accumulated, abrasion of the rails or the shoes by the sludge is significant. In addition, when rails are arranged on the bottom surface of the settling pond, collection of the sludge accumulated around the rails is extremely difficult.

! ’

[0004]

Thus, for example, in Japanese Unexamined Patent Application Publication No. 53-55655 and Japanese Unexamined Patent Application Publication No. 3-238006, sludge collectors have been proposed in which the flights are formed to float with the chains due to the buoyancy, and restraining rails, which prevent the flights from floating when the flights are on the lower side of the settling pond, are provided on the flights.

In the sludge collector, since the restraining rails where the shoes of the flights slide are arranged to be distanced from the bottom surface of the settling pond, the abrasion of the rails or the shoes due to the sludge accumulated on the bottom surface of the settling pond can be suppressed. In addition, since obstacles are not present on the bottom surface, the accumulated sludge can be collected evenly and discharged.

[0005]

However, in such a sludge collector, even in the device in which the chains and the flights are sunk by their own weight, and even in the device in which the chains and the flights are emerged in the treated water, when the chains themselves are elongated and the tension thereof is weakened by the abrasion or the like, the chains cannot be stably rotationally driven and in some cases, the chains may be dislocated from sprockets where the chains are wound. Thus, when the elongation of the chains becomes large, the operation of the collector is stopped and the treated water of the settling pond is drained and thereby adjustment work of the tension of the chains such as moving the shafts of the sprockets or decreasing the number of links of the chains should be performed. Accordingly, the settling process of the sludge in the settling pond cannot be performed during the work.

[0006]

In the device in which the chains and the flights are sunk in the treated water due to the their own weight, a portion which gets slack downward is provided on a drive path of the chains in the upper side so that at the portion, the chains and the flights are sunk due to the their own weight and thereby the tension can be applied to the whole of the chains. Thus, the frequency of the adjustment work of the tension of the chains can be decreased to some extent. However, in the device in which the chains and the flights emerge in the treated water, the tension cannot be applied by the means described above.

[0007]

Accordingly, in such a device in which the chains and the flights float in the treated water, a device for applying the tension to the chains, for example, such as the pressing member disclosed in Japanese Unexamined Patent Application Publication No. 2009-241022 should be provided. As a result, the structure of the collector becomes complicated and when large tension is always applied to the chains as disclosed in

Japanese Unexamined Patent Application Publication No. 2009-241022, conversely, the elongation of the chains is promoted and thereby the frequency of the adjustment work of the tension of the chains may be increased. ]

SUMMARY OF THE INVENTION

[0008]

The invention is achieved based on the background described above and an object of the invention is to provide a sludge collector in which the frequency of adjustment work of the tension of chains can be decreased without requiring a device for applying the tension to the chains such as the pressing member described above, in the sludge collector having a sludge collecting body formed of chains and flights, which are configured to float in the treated water.

In order to solve the problems described above and to achieve the object thereof, a sludge collector of the invention is configured to include a sludge collecting body in which flights collecting sludge accumulated on a bottom surface of a sludge settling pond are attached to chains which are arranged to wind endlessly and are rotationally driven in the sludge settling pond. The sludge collecting body is configured to float in treated water inside the sludge settling pond. In addition, an upper rail which restrains emerging of the sludge collecting body and a chain tension area where the upper rail is not provided and which allows the emerging of the sludge collecting body in the treated water are provided on a drive path of the sludge collecting body of the upper side in the sludge settling pond.

[0010]

In the sludge collector configured as described above, the upper rail and the chain tension area where the upper rail is not provided are provided at the drive path of the sludge collecting body of the upper side in the sludge settling pond. Thus, in order to float in the treated water inside the settling pond, the sludge collecting body configured of the chains and the flights floats in the treated water at the chain tension area and the floated portion is pulled so that the tension is applied to the whole of the chains.

[0011]

Accordingly, even though the elongation occurs in the chains, the elongation is absorbed by the chain tension area and the situation in which the chains are dislocated from the sprockets can be prevented. In addition, the elongation described above is absorbed between the water surface of the treated water in the sludge settling pond and the upper surface of the sludge collecting body at the chain tension area so that the frequency of the adjustment work of the tension of the chains can be decreased.

[0012]

Thus, as described above, there is no need to provide a device or the like applying large tension to the chains. In addition, the buoyancy of the sludge collecting body in the chain tension area is appropriately set, and the tension, which is applied to 5 the whole of the chains, can be adjusted so as not to become excessively large.

Accordingly, the situation in which, conversely, the excessive tension is applied to the chains and the chains are elongated can be prevented. : [0013]

Here, an end section of the upper rail adjacent to the chain tension area is formed to bend upward toward to the side of the chain tension area. Accordingly, the chains floating at the chain tension area are prevented from being pulled and damaged by the end section of the upper rail.

[0014]

In addition, the chains may be configured such that a portion of the drive path of the upper side emerges on the water surface of the treated water held inside the sludge settling pond, or the whole of the drive path may be arranged in the treated water. In this case, when the chains have a structure in which the chains wind around only a pair of sprockets provided at both ends of the drive path, the sprockets are formed by a minimum number, and thereby the structure of the sludge collector can be further simplified.

[0015]

Particularly, when the chains are wound around the pair of sprockets and the whole of the drive path is arranged in the treated water, the drive path of the upper side and the drive path of the lower side of the sludge collecting body when the flights collect : the sludge can be provided vertically close to each other. Accordingly, similar to the collectors disclosed in Japanese Unexamined Patent Application Publication No. 53-55655 and Japanese Unexamined Patent Application Publication No. 3-238006, when the lower rail which restrains the emerging of the sludge collecting body is also provided at the drive path of the lower side, at least a portion of the upper rail and the lower rail can be supported by the common supporting member provided inside the sludge settling pond. Thus, the structure of the collector device can be simplified, and the collector device can be effectively provided at a low cost.

[0016]

As described above, according to the invention, the appropriate tension can always be applied to the whole of the chains, the frequency of the adjustment work of the tension of the chains is decreased and thereby delay in the processing can be suppressed to a minimum in the sludge settling pond without complicating the structure of the collector by requiring the device for applying the tension to the chains.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017]

FIG. 1 is a plan view illustrating a first embodiment of the invention.

FIG. 2 is a cross-sectional view taken along line AA in FIG. 1.

FIG. 3 is a cross-sectional view taken along line BB in FIG. 2.

FIG. 4 is a cross-sectional view taken along line CC in FIG. 2. :

FIG. 5 is a cross-sectional view taken along line DD in FIG. 2.

FIG. 6 is a plan view illustrating a second embodiment of the invention.

FIG. 7 is a cross-sectional view taken along line AA in FIG. 6.

FIG 8 is a cross-sectional view taken along line BB in FIG.7.

DETAILED DESCRIPTION OF THE INVENTION

[0018]

FIGS. 1 to 5 illustrate a first embodiment of the invention. In the embodiment, as shown in FIGS. 1 and 3 to 5, two sludge settling ponds P are arranged in parallel having the same shape and the same size with a rectangular shape in a plan view, and also sludge collectors of the embodiment having also the same shape and the same size, and the same structure are arranged at both sides of the sludge settling pond P respectively. Thus, in FIGS. 1 and 3 to 5, reference numerals are arranged only at the sludge collector in the sludge settling pond P of one side and are omitted on the other side.

[0019]

The sludge settling pond P is formed to be surrounded by a bottom surface Q which has the rectangular shape described above, a pair of long wall surfaces R which stand up from the bottom surface Q in the vertical direction, extend in the longitudinal direction of the rectangular shape, and are parallel to each other, and a pair of short wall surfaces S which are perpendicular to the long wall surfaces R and the bottom surface Q and are opposite in the longitudinal direction. ~~ One side of the short wall surfaces S (the short wall surface S of the left side in FIGS. 1 and 2) in the bottom surface Q is deepened in one step and thereby it becomes a sludge discharging pit T where the collected sludge is discharged. In addition, at a corner section where the bottom surface

Q and the pair of long wall surfaces R intersect, inclined surfaces U are formed to approach each other toward the side of the bottom surface Q.

[0020]

As shown in FIG. 2, sprocket support shafts 1 are protruded and disposed respectively perpendicular to the both long wall surfaces R in order to have the same axis

' from the long wall surfaces R at a position directly above a boundary portion between the sludge discharging pit T and the bottom surface Q, and at a position directly above the bottom surface Q at the other side of the short wall surface S (the short wall surface S of the right side in FIGS. 1 and 2) of the pair of short wall surfaces S. In addition, as shown in FIGS. 3 and 5, sprockets 2A and 2B are rotatably attached to the tips of the sprocket support shafts 1 around the axis. In addition, the sprockets 2B of the other side of the short wall surface S described above are attached to the sprocket support shaft 1 independently each other and thereby are cantilevered, while the sprockets 2A of the side of the sludge discharging pit T are connected by a through shaft 3 and thereby can be integrally rotatable.

[0021]

In addition, at one of two sprockets 2A arranged at the side of the sludge discharging pit T, a driving sprocket 4 is attached as integrally rotatable around the axis with the sprocket 2A of the side. The driving sprocket 4 is connected to a rotation shaft of adriving device 5 disposed on the sludge settling pond P through a chain or the like.

In addition, the rotation shaft of the driving device 5 is rotated so that two sprockets 2A connected by the driving sprocket 4 and the through shaft 3 are rotated about the axis in a predetermined direction (in a clockwise direction in FIG. 2). In addition, as shown in

FIGS. 1 and 3, the driving sprocket 4 is attached to the sprocket 2A positioned at the tip of the sprocket support shaft 1 projected from the long wall surface R adjacent to each other between each of the sludge collectors in two sludge settling ponds P.

[0022]

Thus, at total four of sprockets 2A and 2B arranged inside one sludge settling pond P, the pair of sprockets 2A and 2B each other positioned at the tip of the sprocket support shafts 1 protruded from the same long wall surface R of the pair of long wall i surfaces R are positioned respectively on the same vertical surface to be distanced from each of the long wall surfaces R. In addition, at the pair of sprockets 2A and 2B, chains 6 are wound respectively in an endless winding manner inside the same vertical surface.

[0023]

Accordingly, in the embodiment, as shown in FIGS. 1, 3 to 5, in one sludge settling pond P, a pair of chains 6 is positioned at the sides of both long wall surfaces R.

Thus, the driving device 5 rotates the sprockets 2A and thereby the chains 6 rotate the sprockets 2B, while the chains 6 are rotationally driven between the pair of sprockets 2A and 2B inside the vertical surfaces in a drive direction F, the same direction as the predetermined direction. In addition, the length of the chain 6 is longer than that of a case where the chain is wound tightly around the pair of sprockets 2A and 2B.

[0024]

In addition, a plurality of flights 7 is hung over at the pair of chains 6 positioned at the sides of both the long wall surfaces R. Each of the flights 7 is hung over to extend perpendicular to the vertical surfaces between both the chains 6. Thus, both end ] sections of each of the flights 7 are attached respectively at outside of rings formed by the chains 6. As shown in FIGS. 3 to 5, the length of the flight 7 in the perpendicular direction to the vertical surfaces is set to be longer than the distance between the pair of chains 6 and is set to be slightly shorter than the width of the bottom surface Q between the inclined surfaces U of the sludge settling pond P. As the result, each of the flights 7 is positioned between the inclined surfaces U on the bottom surface Q. In addition, as shown in FIG. 2, the flight 7 includes a collecting surface 7A which is always vertical to a direction where the chains 6 are extended. A plurality of flights 7 are arranged with the same interspatial distance along the longitudinal direction of the chains 6 and thereby constitute a sludge collecting body 8 in the embodiment.

[0025]

Furthermore, the sludge collecting body 8 configured as described above is constituted to emerge in treated water W introduced inside the sludge settling pond P.

As described above, in order to emerge the sludge collecting body 8 in the treated water W, for example, in a case where the chains 6 sink in the treated water W, the flights 7 are emerged in the treated water W and the whole of the sludge collecting body 8 is emerged on the treated water W. Alternatively, the chains 6 emerging in the treated water W and the flights 7 sinking in the treated water W may be assembled. In addition, both the flights 7 and the chains 6 may be configured to emerge in the treated water W.

[0026]

However, as described below, the tension is applied to the chain 6, so that it is desirable to secure strength while achieving lightening of the chain 6 even though the chain 6 sinks in the treated water W. In order to satisfy the requirement described above, the chain 6 is formed of, for example, plastic such as reinforced polyester resin or polyacetal resin. In addition, it is desirable that the flight 7 be configured to emerge in the treated water W by further larger buoyancy and the whole of the sludge collecting body § be reliably emerged in the treated water W. As described above, in order to emerge the whole of the sludge collecting body 8 in the treated water W with a further larger buoyancy of the flight 7, the flight 7 itself is, for example, formed of a hollow shape of high-strength material with the light weight such as fiber reinforcing resin or the like. Alternatively, a float having such the hollow shape of a float or a float formed of styrofoam having low specific gravity itself may be attached at a rear surface of the collecting surface 7A of the flight 7.

[0027]

Furthermore, shoes 7B are attached at the both ends of the flight 7 protruded to the outside of the pair of chains 6 respectively. In addition, the shoes 7B are slidably in contact with an upper rail 9A and a lower rail 9B from below. The upper rail 9A and the lower rail 9B are long plate-shaped members provided to be extended along the longitudinal direction up and down of the sprockets 2A and 2B inside the sludge settling pond P. As described above, the upper rail 9A and from the upper side, the lower rail 9B press down the flights 7 of the sludge collecting body 8 which is subject to emerging in the treated water W and thereby guiding the flights 7 in the longitudinal direction thereof. Accordingly, the portion in contact with the upper rail 9A and the portion in contact with the lower rail 9B of the flight 7 become the opposite side each other. Thus, the shoes 7B are attached both sides (the frond and the rear) of the flight 7, respectively.

[0028]

In addition, as shown in FIG. 2, the lower rail 9B is disposed to be extended to substantially entire length of the bottom surface Q in parallel with the bottom surface Q of the sludge settling pond P between lower edge sections of the pair of sprockets 2A and 2B. Thus, as shown in FIGS. 3 to 5, the flight 7 where the shoes 7B are slidably in contact with the lower rail 9B is configured such that the tip edge which faces the lower side thereof is arranged to face the bottom surface Q to be slightly distanced from the bottom surface Q of the sludge settling pond P.

[0029]

Accordingly, when the chains 6 are rotationally driven on the drive path of the sludge collecting body 8 of the lower side of the sprockets 2A and 2B inside the sludge settling pond P, the flights 7 move along the lower rail 9B to be slightly distanced from the bottom surface Q in the running direction F, in other words, in a direction facing from the short wall surface S of the other side of the sludge settling pond P to the side of the sludge discharging pit T in parallel to the bottom surface Q. The sludge accumulated on the bottom surface Q is collected and is discharged to the sludge discharging pit T.

[0030]

Meanwhile, as shown in FIG. 2, the upper rail 9A is also arranged to be extended to the side of the sprocket 2B of the other side in parallel to the lower rail 9B slightly upward from the upper edge section of the sprocket 2A of one side. However, as described above, in the embodiment, the upper rail 9A is interrupted in the middle from the side of the sprocket 2A of one side to the sprocket 2B of the other side, while the lower rail 9B is arranged throughout between the pair of sprockets 2A and 2B. Thus, at the drive path of the sludge collecting body 8 of the upper side of the sprockets 2A and 2B inside the sludge settling pond P, an area where the upper rail 9A is not disposed is formed at the side of the sprocket 2B of the other side so that the area becomes a chain tension area X in the embodiment.

[0031]

At the chain tension area X, the sludge collecting body 8 configured to float in the treated water W bulges out so as to float and expand to the upper side without being pressed by the upper rail 9A. After that, the chain 6 is wound around the sprocket 2B of the other side and is withdrawn to the lower side to be delivered to the drive path of the lower side. In addition, the length of the chain 6 is set so that the sludge collecting body 8 emerging at the chain tension area X emerges only inside the treated water W accumulated in the sludge settling pond P. As the result, the flight 7 or the chain 6 does not emerge on the water surface of the treated water W at the chain tension area X. In addition, as shown in FIG. 2, an end section adjacent to the chain tension area X of the upper rail 9A is formed to bend upward toward to the side of the chain tension area X.

[0032]

In addition, the upper rail 9A and the lower rail 9B are supported by a common supporting member 10 provided inside the sludge settling pond P except the chain tension area X where the upper rail 9A is not provided. In other words, as shown in FIG. 4, at an area where the upper rail 9A is extended in parallel to the lower rail 9B, at the position where the upper rail 9A is arranged in the upward and downward direction, angular column-shaped upper supporting sections 10A of the supporting members 10 are vertically protruded from the pair of long wall surfaces R of the sludge settling pond P with the same interspatial distance in the longitudinal direction. Also, the upper rail 9A is attached at the lower surface of the tip of the upper supporting section 10A.

[0033]

In addition, at the lower surface of the upper supporting section 10A of the back end side (the side of the long wall surface R) slightly away from the tip where the upper rail 9A is attached, an L-shaped angular columnar lower supporting section 10B, which bends in parallel to the upper supporting section 10A after extending downward, is attached without interfering with the inclined surface U. The lower rail 9B is attached at the lower surface of the tip of the lower supporting section 10B. In addition, at the chain tension area X where the upper rail 9A is not provided, the supporting member 10, where the tip of the upper supporting section 10A to be attached to the vpper rail 9A is removed, may be arranged.

[0034]

In the sludge collector configured described above, the sludge collecting body 8 configured of the chain 6 and the flight 7, emerges in the treated water W inside the sludge settling pond P. Accordingly, at the drive path of the lower side, the shoes 7B of the flight 7 are in contact with the lower rails 9B from below, which is arranged at the upper side of the flight 7. In addition, the flight 7 moves in the running direction F as described above while the flight 7 is pressed down from above by moving along the lower rail 9B. Thus, the sludge is collected and discharged to the sludge discharging pit

T. Accordingly, a distance is formed between the bottom surface Q of the sludge settling pond P where the sludge is accumulated and the lower rail 9B. As the result, it is possible to prevent the abrasion of the lower rail 9B or the shoe 7B without sliding the shoe 7B to the lower rail 9B in the accumulated sludge.

[0035]

In addition, as described above, the lower rail 9B is arranged upward to be distanced from the bottom surface Q. Accordingly, it is possible to avoid an obstacle being placed in the bottom surface Q and thereby the sludge accumulated in the bottom surface Q is collected evenly and can be reliably discharged by the flight 7. Specifically, in the embodiment, the supporting members 10 supporting the lower rail 9B or the upper rail 9A, or the sprocket support shafts 1 rotatably support the sprockets 2A and 2B are also protruded from the long wall surfaces R of the sludge settling pond P so that these members do not become obstacles when the sludge is collected.

[0036]

On the other hand, the area, where the upper rail 9A is provided which is in contact with the shoe 7B of the flight 7 and which restrains the emerging of the sludge collecting body 8, and the chain tension area X where the upper rail 9A is provided are provided at the drive path of the upper side within the sludge settling pond P. Thus, the ) sludge collecting body 8 is freely emerged, at the chain tension area X, in the treated water W so that the tension is applied to the whole of the chain 6. Thus, even though elongation occurs in the chain 6 due to the abrasion, the elongation is absorbed by the emerging of the chain 6 in the chain tension area X and thereby the tension of the chain 6 can be prevented from weakening.

Thus, according to the sludge collector having the configuration described above, the buoyancy of the sludge collecting body 8 or the section where the chain tension area

X is provided is appropriately set so that the proper tension can be always applied to the chain 6 only by emerging the sludge collecting body § at the chain tension area X. As

S the result, the chain 6 where the elongation occurs can stably and effectively perform the collection of the sludge without being dislocated from the sprockets 2A and 2B.

[0038]

Moreover, since the elongation of the chain 6 is absorbed between the water surface of the treated water W and the upper surface of the emerged sludge collecting body 8 at the chain tension area X, the distance between the water surface of the treated water W and the upper surface of the sludge collecting body 8 allows enough space.

Accordingly, the frequency of the adjustment work of the tension of the chain can be decreased. Furthermore, since there is no need to be separately provide a device for applying the tension to the chain 6 as described above, the structure of the sludge collector can be prevented from complicating. In addition, the life of the chain 6 is not shortened without applying larger tension to the chain 6 than necessary.

[0039]

In addition, in the embodiment, the end section of the upper rail 9A adjacent to the chain tension area X is bent upward toward the side of the chain tension area X.

Thus, as described above, the chain 6 or the flight 7 of the sludge collecting body 8 which emerges at the chain tension area X is not caught at the end section thereof and thereby the member does not need to be damaged. Accordingly, the chain 6 and the flight 7 are smoothly emerged at the chain tension area X and the frequency of the adjustment work of the tension of the chain can be further reliably decreased.

’

Meanwhile, in the embodiment, the whole of the drive path of the sludge collecting body 8 is arranged in the treated water W held by the sludge settling pond P and each chain 6 is wound and is rotationally driven on only the pair of sprockets 2A and 2B arranged at both ends of the drive path thereof. In other words, the drive path of the sludge collecting body 8 is formed by a minimum number of the sprockets 2A and 2B with respect to one chain 6 so that the structure of the sludge collector can be further simplified.

[0041]

However, the chain 6 is wound around only the pair of sprockets 2A and 2B and the whole of the drive path is arranged in the treated water W so that the drive path of the upper side and the drive path of the lower side of the sprockets 2A and 2B can approach to each other. Accordingly, the distance between the upper rail 9A and the lower rail 9B can also be minimized except the chain tension area X of the sludge collecting body 8 which runs around the drive path. Thus, the supporting member 10 which supports the upper rail 9A and the lower rail 9B also becomes common at the portion where these members are extended in parallel. Thus, according to the embodiment, the structure of the sludge collector can be simplified. Furthermore, the sludge collector, which is stable in collecting the sludge as described above, with lower cost, can be provided.

[0042]

In addition, in the first embodiment described above, the chain 6 is wound around only the pair of sprockets 2A and 2B and the whole of the drive path of the sludge collecting body 8 is arranged in the treated water W. Meanwhile, for example, as the second embodiment shown in FIGS. 6 to 8, the chain 6 may be wound around two or more sprockets 2 and thereby form the drive path. In addition, at the portion except the chain tension area X, the flight 7 of the sludge collecting body 8 may emerge on the water surface of the treated water W. In addition, in the second embodiment, the common portions with the first embodiment are denoted by the same reference numerals and a repeated description thereof will be omitted here. In addition, the views corresponding to the cross-section CC and the cross-section DD in FIG. 2 are common to the first embodiment so that the illustration thereof is omitted here.

[0043]

In the second embodiment, the lower side portion of the pair of sprockets 2A and 2B and the portion of the chain tension area X of the drive path of the sludge collecting body 8 are the same as the first embodiment. Meanwhile, a third sprocket 2C is arranged slightly more downward than the position of the water surface of the treated water W upward the sprocket 2A of the one side of the pair of sprockets 2A and 2B.

Furthermore, at the side of the short wall surface S of the other side of the third sprocket 2C, a fourth sprocket 2D is also arranged to be positioned slightly downward than the position of the water surface of the treated water W with a interval with the third sprocket 2C in the longitudinal direction. In addition, the driving sprocket 4 is attached to the third sprocket 2C and connected to the rotation shaft of the driving device 5.

[0044]

In addition, in the embodiment, the end section of the side of the short wall : surface S of one side of the upper rail 9A is positioned on the water surface of the treated water W above the fourth sprocket 2D. The upper rail 9A is lowered and input in the treated water W toward to the side of the short wall surface S of the other side, in other words, to the side of the chain tension area X. The upper rail 9A is bent upward and ; interrupted toward to the side of the chain tension area X after the upper rail 9A is in ; parallel to the lower rail 9B, substantially at the center portion of the sludge settling pond

Pin the longitudinal direction, in the same manner as in the first embodiment.

In addition, at the portion where the upper rail 9A and the lower rail 9B are extended in parallel each other, the upper rail 9A and the lower rail 9B are protruded from the long wall surface R of the sludge settling pond P and supported by the common supporting member 10, in the same manner as the first embodiment.

[0045]

Even in the sludge collector of the second embodiment configured described above, the sludge collecting body 8 configured of the chain 6 and the flight 7, in the same manner as the first embodiment, floats in the treated water W at the chain tension area X and the tension is applied to the whole of the chain 6. Thus, even though the elongation occurs in the chain 6 due to the abrasion or the like, the elongation is absorbed by the emerging of the chain 6 in the chain tension area X and thereby the chain 6 and the flight 7 can be stably rotationally driven. In addition, since the end section of the upper rail 9A adjacent to the chain tension area X is bent upward, the flight 7 or the like can be prevented from being caught. Moreover, at least at the portion where the upper rail 9A and the lower rail 9B are in parallel each other, these members can be supported by the common supporting member 10 so that the structure of the device can be prevented from being complicated.

[0046]

Furthermore, in the second embodiment, the chain 6 is also wound around the third and the fourth sprockets 2C and 2D positioned slightly more downward than the position of the water surface of the treated water W. Accordingly, the flight 7 is positioned at the upper side of the chain 6 in the portion between the third and the fourth sprockets 2C and 2D. As the result, in combination with the constitution in which the sludge collecting body 8 configured of the chain 6 and the flight 7 emerges in the treated water W, as shown in FIG. 7, the upper portion of the flight 7 can be emerged from the water surface of the treated water W between the third and the fourth sprockets 2C and 2D.

[0047]

Thus, according to the embodiment, the sludge accumulated at the bottom surface Q of the sludge settling pond P is collected and discharged to the sludge discharging pit T by the flight 7 and further scum floating near the water surface can be collected by the flight 7 which is emerged from the water surface of the treated water W between the third and the fourth sprockets 2C and 2D. Thus, the means for discharging the scum which is collected as described above is provided, for example, adjacent to the fourth sprocket 2D in the side of the running direction F of the chain 6. Accordingly, the purification of the treated water W introduced in the sludge settling pond P can be further enhanced.

[0048]

In addition, in the first and the second embodiments, the chain tension area X is provided at the end portion (the portion where the chain 6 is wound around the sprocket 2B of the other side) of the side of the running direction F in the drive path of the sludge collecting body 8 of the upper side. However, as the first embodiment, when the whole of the drive path of the chain 6 is positioned in the treated water W inside the sludge settling pond P, the chain tension area X may be provided at the portion where the chain 61s wound around the sprocket 2A of one side, that is, at the end section forward of the drive path of the upper side in the running direction F. Alternatively, for example, the upper rails 9A are arranged at the upper side of the pair of sprockets 2A and 2B respectively and the upper rail 9A is not provided at other portions thereof and thereby the portions may become the chain tension area X. Furthermore, a plurality of the chain tension areas X may be provided.

As described above, preferred embodiments of the invention are disclosed, ‘ however, the invention is not limited to the embodiments.

While preferred embodiments of the invention have been described and illustrated above, it should be understood that these are exemplary of the invention and are not to be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit or scope of the present invention. Accordingly, the invention is not to be considered as being limited by the foregoing description, and is only limited by the scope of the appended claims.

Claims

What is claimed is:

1. Asludge collector comprising: a sludge collecting body in which flights collecting sludge accumulated on a bottom surface of a sludge settling pond are attached to chains which are arranged to wind endlessly and are rotationally driven in the sludge settling pond, wherein the sludge collecting body is configured to float in treated water inside the sludge settling pond, and an upper rail which restrains emerging of the sludge collecting body and a chain tension area where the upper rail is not provided and which allows the emerging of the sludge collecting body in the treated water are provided on a drive path of the sludge collecting body of the upper side in the sludge settling pond.

2. The sludge collector according to claim 1, wherein an end section of the upper rail adjacent to the chain tension area is formed to bend upward toward to the side of the chain tension area.

3. The sludge collector according to claim 1 or 2, wherein whole of the drive path is arranged in the treated water and the chain is wound around only a pair of sprockets provided at both ends of the drive path thereof.

4. The sludge collector according to the claim 1 or 2, wherein a lower rail which restrains the emerging of the sludge collecting body is provided at the drive path of the sludge collecting body of the lower side in the sludge settling pond and at least a portion of the lower rail and the upper rail is supported by a common supporting member provided in the sludge settling pond.

5. The sludge collector according to the claim 3, wherein a lower rail which restrains the emerging of the sludge collecting body is provided at the drive path of the sludge collecting body of the lower side in the sludge settling pond and at least a portion of the lower rail and the upper rail is supported by a common supporting member provided in the sludge settling pond.

What is claimed is: :

1. Asludge collector comprising: ] a sludge collecting body in which flights collecting sludge accumulated on a bottom surface of a sludge settling pond are attached to chains which are arranged to wind endlessly and are rotationally driven in the sludge settling pond, wherein the sludge collecting body is configured to float in treated water inside the sludge settling pond, and an upper rail which restrains emerging of the sludge collecting body and a chain tension area where the upper rail is not provided and which allows the emerging of the sludge collecting body in the treated water are provided on a drive path of the sludge collecting body of the upper side in the sludge settling pond.

4. The sludge collector according to the claim 1 or 2, wherein a lower rail which restrains the emerging of the sludge collecting body is provided at the drive path of the sludge collecting body of the lower side in the sludge settling pond and at least a portion of the lower rail and the upper rail is supported by a :

common supporting member provided in the sludge settling pond.