Sedimentation device

Abstract

To provide a sedimentation device with a scum pipe in a circular tank where countermeasures corresponding to the unsatisfactory action of the scum pipe and the removal of scum can be efficiently and continuously performed.SOLUTION: A sedimentation device provided as one step to solve problems comprises: a shaft being installed in a circular tank and rotationally driven by a drive part; a rake; a scum pipe being cylindrical, being installed freely rotatably around a shaft and having an opening to take scum in, a lower bar and an upper bar; a striker contacting with the upper bar by the rotation of the shaft; and a kicker contacting with the lower bar by the rotation of the shaft, the striker or the kicker having a roller structure. In the sedimentation device having the scum pipe in the circular tank, the abrasion of components is suppressed, the occurrence of troubles on the action of the scum pipe is suppressed, and the removal of scum can be efficiently continued.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present invention relates to a sedimentation device for sedimenting sludge and the like in a circular tank. More specifically, the present invention relates to a sedimentation device that discharges scum from a scum pipe provided in a circular tank.

Background Art

[0002] As one of the water treatment facilities for treating water to be treated, a sedimentation device that separates the water to be treated into sludge and supernatant in a circular tank is known. In addition, in this sedimentation device, in order to remove scum floating on the liquid surface of the circular tank, a skimmer arm and a scum blade for scraping the scum in conjunction with a rake that rotates the bottom of the circular tank to scrape the sludge, and a scum skimmer composed of a scum blade, and a scum pipe that takes in this scum and discharges it to the outside of the circular tank are provided.

[0003] For example, Non-Patent Document 1 describes that in a sedimentation device having a circular tank, a scum pipe (pipe skimmer) that extends in the radial direction of the circular tank and is rotatable around an axis is provided for scum removal, and an operating device for rotating the scum pipe by an operating plate provided on the scum skimmer is provided on this scum pipe. Non-Patent Document 1 also describes that when rotating the shaft (main shaft) that rotatably supports the scum skimmer, the scum skimmer scrapes the scum floating on the liquid surface, and as the scum skimmer rotates, the operating plate provided on the scum skimmer tilts the scum pipe via the operating device of the scum pipe. Further, when the scum pipe tilts and the opening opens into the water, the scum scraped by the scum skimmer is taken into the scum pipe and discharged to the outside of the circular tank.

Prior Art Documents

Non-Patent Documents

[0004]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Here, the precipitation device described in Non-Patent Document 1 is such that after the opening of the scum pipe opens underwater due to the movement of the operating plate provided on the scum skimmer, the operating plate further moves to return the opening of the scum pipe to its original position (above the liquid level). However, during the operation of such a precipitation device, problems related to the operation of the scum pipe may occur, such as the opening of the scum pipe not returning to its original position even when the operating plate moves, and the opening of the scum pipe not being in the predetermined position, making it difficult to continuously and efficiently remove scum.

[0006] An object of the present invention is to provide a precipitation device that has a countermeasure against problems related to the operation of a scum pipe in a precipitation device equipped with a scum pipe in a circular tank and enables efficient continuous removal of scum.

Means for Solving the Problems

[0007] As a result of intensive studies on the above problems, the inventor of the present invention has obtained the knowledge that problems related to the operation of the scum pipe in a precipitation device equipped with a scum pipe in a circular tank are caused by wear of parts due to continuous use or displacement from the suitable position related to the part arrangement. And the inventor of the present invention has completed the present invention by providing a structure capable of suppressing wear on some parts of the precipitation device or a mechanism capable of adjusting the position of some parts, thereby having a countermeasure against problems related to the operation of the scum pipe and enabling efficient continuous removal of scum. That is, the present invention is the following precipitation device.

[0008] The precipitation device of the present invention for solving the above problems includes a shaft provided to extend vertically at the center of a circular tank, a drive unit for rotationally driving the shaft, a rake fixed to the shaft at the bottom of the circular tank, and a cylindrical shape formed to extend in the radial direction of the circular tank at the liquid level of the circular tank and provided to be rotatable about the axis. A scum pipe having an opening for taking in scum floating on the liquid surface, a lower bar extending downward when the opening faces upward, and an upper bar extending obliquely upward when the opening faces upward, a striker that contacts the upper bar by the rotation of the shaft, and a kicker that contacts the lower bar by the rotation of the shaft, characterized in that the striker or the kicker has a roller structure. The inventor has found that the problems related to the operation of the scum pipe are caused by wear of parts due to continuous use. In particular, when the kicker pushes the lower bar to tilt the scum pipe and the striker pushes the upper bar to return the scum pipe to its original position, wear occurs at the respective contact parts, causing the opening of the scum pipe not to stay in the predetermined position. According to this precipitation device, in a precipitation device provided with a scum pipe in a circular tank, as a countermeasure against problems related to the operation of the scum pipe, by making the kicker that contacts the lower bar provided on the scum pipe or the striker that contacts the upper bar provided on the scum pipe have a roller structure, friction at the contact parts between the lower bar and the kicker, or the upper bar and the striker can be reduced, and wear suppression (extended service life) of parts can be achieved. Thereby, the occurrence of factors causing problems related to the operation of the scum pipe can be suppressed, and efficient continuous removal of scum can be achieved.

[0009] The precipitation device of the present invention for solving the above problems includes a shaft provided to extend vertically at the center of a circular tank, a drive unit for rotationally driving the shaft, a rake fixed to the shaft at the bottom of the circular tank, and a cylindrical shape formed to extend in the radial direction of the circular tank at the liquid level of the circular tank and provided to be rotatable about the axis. A scum pipe having an opening for taking in scum floating on the liquid surface, an upper bar extending obliquely upward when the opening faces upward, and a lower bar extending downward when the opening faces upward, a striker that contacts the upper bar by the rotation of the shaft, and a kicker that contacts the lower bar by the rotation of the shaft, and a vertical position adjustment mechanism is provided on the striker. The inventor has found that the problem related to the operation of the scum pipe is caused by the deviation from the suitable position related to the component arrangement. In particular, the arrangement of the striker that pushes the upper bar to return the scum pipe to the original position deviates from the suitable position, resulting in the opening of the scum pipe not being able to be within the predetermined position. According to this precipitation device, in a precipitation device provided with a scum pipe in a circular tank, as a countermeasure against the problem related to the operation of the scum pipe, by providing a mechanism that enables vertical position adjustment in the striker that contacts the upper bar provided on the scum pipe, it becomes possible to adjust the arrangement of the striker so that the operation of the scum pipe becomes optimal. Thereby, it is possible to suppress the occurrence of the cause of the problem related to the operation of the scum pipe and to efficiently continue the removal of scum.

[0010] The precipitation device of the present invention for solving the above problems includes a shaft provided to extend vertically at the center of a circular tank, a drive unit for rotationally driving the shaft, a rake fixed to the shaft at the bottom of the circular tank, and a cylindrical shape formed to extend in the radial direction of the circular tank at the liquid level of the circular tank and provided to be rotatable around the axis. A scum pipe having an opening for taking in scum floating on the liquid level, an upper bar extending obliquely upward when the opening faces upward, and a lower bar extending downward when the opening faces upward, a striker that abuts against the upper bar by the rotation of the shaft, and a kicker that abuts against the lower bar by the rotation of the shaft. The striker or the kicker has a roller structure, and a vertical position adjustment mechanism is provided on the striker. As described above, the present inventor has found that the problems related to the operation of the scum pipe are caused by wear of parts due to continuous use and deviation from the suitable position related to the component arrangement. According to this precipitation device, in a precipitation device provided with a scum pipe in a circular tank, as a countermeasure against problems related to the operation of the scum pipe, by making the kicker that abuts against the lower bar or the striker that abuts against the upper bar for tilting the scum pipe have a roller structure, the friction at the contact portion between the lower bar and the kicker, or the upper bar and the striker is reduced, wear of parts is suppressed (extended service life), and a mechanism that enables vertical position adjustment is provided in the striker that abuts against the upper bar provided on the scum pipe. Thus, it is possible to adjust the arrangement of the striker so that the operation of the scum pipe becomes optimal. Thereby, the occurrence of factors causing problems related to the operation of the scum pipe is suppressed, and it becomes possible to efficiently continue removing scum.

Effect of the Invention

[0011] According to the present invention, in a precipitation device provided with a scum pipe in a circular tank, it is possible to provide a precipitation device having a countermeasure against problems related to the operation of the scum pipe and capable of efficiently continuing to remove scum.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0013] Hereinafter, embodiments of the precipitation device according to the present invention will be described in detail with reference to the drawings. In addition, the precipitation device described in the embodiments is merely an example for explaining the precipitation device according to the present invention and is not limited thereto.

[0014] [First Embodiment] [Precipitation Device] Figures 1 and 2 are schematic explanatory views showing the structure of the precipitation device according to the first embodiment of the present invention. Note that Figure 1 is a longitudinal sectional view of the precipitation device, and Figure 2 is a top view of the precipitation device. As shown in Figures 1 and 2, the precipitation device 1 according to the present embodiment includes a circular tank 2 into which the water to be treated W is introduced, a shaft 3 provided to extend vertically at the center of the circular tank 2, a drive unit 4 for rotationally driving the shaft 3, a rake 5 fixed to the shaft 3 at the bottom of the circular tank 2, a scum pipe 6 for taking in the scum S floating on the liquid surface of the circular tank 2 and discharging it to the outside of the circular tank 2, and a scum skimmer 7 for scraping the scum S floating on the liquid surface of the circular tank 2 and guiding it to the scum pipe 6. Further, the precipitation device 1 according to the present embodiment includes a striker 8 and a kicker 9 that come into contact with an upper bar 63 and a lower bar 64 provided on the scum pipe 6 due to the rotation of the shaft 3.

[0015] The precipitation device 1 according to the present embodiment separates sludge from the water to be treated W to be introduced, separating it into sludge and supernatant. Further, the precipitation device 1 according to the present embodiment removes the scum S floating on the liquid surface in the circular tank 2 by including the scum pipe 6 and the scum skimmer 7. Hereinafter, each component of the precipitation device 1 will be described in detail.

[0016] The circular tank 2 is a tank into which the water to be treated W that separates into sludge and supernatant is introduced, and is formed in a circular cross-sectional shape. An overflow weir 21 is provided inward along the inner peripheral surface at the upper part of the inner wall surface of the circular tank 2, and a trough 22 for discharging the supernatant that has flowed into the outside of the circular tank 2 over the overflow weir 21 is provided outside the overflow weir 21. Further, a sludge pit 23 for storing the precipitated sludge and discharging it to the outside of the circular tank 2 is provided at the center of the bottom of the circular tank 2. Note that the bottom of the circular tank 2 is formed in an inverted conical shape that narrows downward toward the center so that the precipitated sludge gathers in the sludge pit 23.

[0017] The shaft 3 is an axis for rotating the rake 5 and the scum skimmer 7, and a motor M is provided thereon as a drive unit 4 for driving the shaft 3. Further, the shaft 3 is formed in a rod shape extending in the vertical direction of the circular tank 2 in order to transmit the rotational driving force of the drive unit 4 to the rake 5 and the scum skimmer 7.

[0018] The drive unit 4 rotationally drives the shaft 3 in the forward rotation direction (the arrow direction (clockwise) in FIG. 2 in this embodiment), and rotates the rake 5 and the scum skimmer 7 in the forward rotation direction.

[0019] The rake 5 rotates on the bottom of the circular tank 2 to scrape up sludge, and is rotatably held by the shaft 3. Further, on the lower surface side of the rake 5, a sludge scraping plate 51 for scraping up the sludge deposited on the bottom of the circular tank 2 and collecting it in the sludge pit 23 is provided.

[0020] As shown in FIGS. 1 and 2, the scum pipe 6 is formed in a cylindrical shape and extends in the radial direction of the circular tank 2 from a position slightly separated from the shaft 3 to the outside of the circular tank 2. The scum pipe 6 is located on the liquid surface and is held by the circular tank 2 so as to be rotatable about the axis R of the shaft.

[0021] In addition, a plurality of openings 61 for taking in the scum S in the circular tank 2 are formed in the scum pipe 6, and a discharge port 62 for discharging the scum S taken in from the openings 61 outside the circular tank 2 is formed. The scum S discharged from the discharge port 62 is separated and treated separately from the water to be treated W, and the water to be treated W is returned to the previous stage.

[0022] An upper bar 63 and a lower bar 64 for rotating the scum pipe 6 in the direction of the axis R of the shaft are fixed to the end of the scum pipe 6 near the shaft 3.

[0023] FIG. 3 is a schematic explanatory diagram showing an example of the structure of the scum pipe in the sedimentation apparatus of this embodiment. Note that FIG. 3A is a front view seen from the shaft 3 side, and FIG. 3B is a longitudinal sectional view. Hereinafter, based on FIG. 3, the upper bar 63 and the lower bar 64 provided on the scum pipe 6 will be described.

[0024] As shown in FIG. 3A, the upper bar 63 is provided on the side end face of the shaft 3 side of the scum pipe 6. In a state where the opening 61 faces upward (hereinafter referred to as the "standby state"), it extends obliquely upward at a predetermined angle β with the vertical direction, and in a state where the scum pipe 6 rotates and the opening 61 is located below the liquid level (hereinafter referred to as the "ingestion state"), it is formed to extend upward. The upper bar 63 is for receiving the pressing force from the striker 8 that orbits as the shaft 3 rotates. For example, it may be composed of a plate-like member having a predetermined strength.

[0025] The lower bar 64 is provided near the end of the shaft 3 side of the scum pipe 6 and is formed to extend downward in the standby state. That is, the lower bar 64 extends in a direction opposite to the opening 61. The lower bar 64 is for receiving the pressing force from the kicker 9 that orbits as the shaft 3 rotates. For example, it may be composed of a bar main body 64a and a locking portion 64b. The bar main body 64a is a portion that contacts the kicker 9 and may be composed of a plate-like member having a predetermined strength. On the other hand, the locking portion 64b is for fixing the bar main body 64a to the scum pipe 6, and examples include a shaft penetrating the scum pipe 6 and joints such as bosses and fastening parts such as nuts. In FIG. 3B, part of the illustration related to the locking portion 64b is omitted.

[0026] The scum skimmer 7 has one end fixed to the shaft 3 and extends in the radial direction of the circular tank 2 to scrape the scum S floating on the liquid surface of the circular tank 2. As the scum skimmer 7, an arm 71 extending in the radial direction of the circular tank 2 is provided above the liquid level of the circular tank 2, and a blade 72 is provided which is tiltably supported with respect to the arm 71 and hangs below the liquid level of the circular tank 2. Further, the blade 72 is formed of an elastic body such as rubber, but may have any shape as long as it can scrape the scum S floating on the liquid surface. For example, it may be a hard plate shape, a soft sheet shape, or a finely divided comb shape.

[0027] The striker 8 and the kicker 9 abut against the upper bar 63 and the lower bar 64 provided on the scum pipe 6 described above by the rotation of the shaft 3 to perform the operation of the scum pipe 6 (rotation of the scum pipe 6). In addition, as the striker 8 in the present embodiment, as shown in FIG. 1, those provided on the scum skimmer 7 can be mentioned. More specifically, those provided at the lower part of the arm 71 on the shaft 3 side rather than the blade 72 can be mentioned. In addition, as the kicker 9 in the present embodiment, as shown in FIG. 1, those fixed to the shaft 3 can be mentioned.

[0028] The striker 8 is for rotating the scum pipe 6 in one direction (clockwise in FIG. 3) around the axis R of the shaft by pushing back the upper bar 63. As shown in FIG. 1, it is at the end of the arm 71 closer to the shaft 3, and extends downward from the position in the radial direction and the vertical direction corresponding to the upper bar 63. The kicker 9 is for rotating the scum pipe 6 in the direction opposite to the rotation by the striker 8 (counterclockwise in FIG. 3) among the one direction around the axis R of the shaft by pushing back the lower bar 64. As shown in FIG. 2, it is at a position slightly above the center of the shaft 3, and extends in the radial direction of the shaft 3 from the position at the height corresponding to the lower bar 64. At this time, the kicker 9 is provided at a predetermined angle α apart from the scum skimmer 7 in the circumferential direction of the scum skimmer 7 (clockwise in FIG. 2). Therefore, the kicker 9 is located at a predetermined angle α in front (upstream side) of the striker 8 hanging down on the arm 71 in the circumferential direction of the shaft 3 (see FIG. 2).

[0029] [Operation of the sedimentation device] Subsequently, the operation of the sedimentation device 1 will be described with reference to FIGS. 1 and 2. In the sedimentation device 1, when the water to be treated W is introduced into the circular tank 2, the water to be treated W is separated into sedimented sludge and supernatant. This supernatant flows over the overflow weir 21 and into the trough 22, and is discharged outside the circular tank 2. On the other hand, the sedimented sludge floats due to the gas generated by decay, and this becomes scum S and floats on the liquid surface. In this state, when the drive unit 4 is driven in the forward rotation direction (clockwise in FIG. 2), the shaft 3 rotates in the forward rotation direction, and the rake 5 and the scum skimmer 7 fixed to the shaft 3 rotate in the forward rotation direction. When the rake 5 rotates, the sludge sedimented at the bottom of the circular tank 2 is scraped by the sludge scraping plate 51, collected in the sludge pit 23, and discharged outside the circular tank 2. At this time, the scum pipe 6 is in a standby state. Then, when the scum skimmer 7 rotates with the rotation of the shaft 3, the scum S floating on the liquid surface of the circular tank 2 is scraped by the blade 72 and guided to the scum pipe 6.

[0030] [Operation of the scum pipe] FIG. 4 is an explanatory diagram showing the operation of the scum pipe in the sedimentation device of the present embodiment. Hereinafter, the operation of the scum pipe 6 during the operation of the sedimentation device 1 will be described with reference to FIG. 4. The structure of the scum pipe 6 shown in FIG. 4 is the same as that shown in FIG. 3B described above, and the structures of the striker 8 and the kicker 9 schematically show the contact portions with the upper bar 63 and the lower bar 64. Also, the white arrows in FIG. 4 indicate the moving directions of the striker 8 and the kicker 9 due to the rotation of the shaft 3.

[0031] As shown in Fig. 4A, for the scum pipe 6 in the standby state, prior to the rotation of the scum skimmer 7, the kicker 9 approaches the scum pipe 6 and abuts against the lower bar 64, pushing the lower bar 64 forward in the moving direction (forward rotation direction) of the shaft 3. Then, when the kicker 9 pushes the lower bar 64, the scum pipe 6 tilts (rotates) in the axial direction from the standby state (see Fig. 4A) towards the suction state (see Fig. 4B). Thereafter, as shown in Fig. 4B, a part of the opening 61 of the scum pipe 6 is submerged below the liquid level to a water depth of dx, and the scum S is collected inside the scum pipe 6 in the suction state. At this time, the upper bar 63 faces upward. Then, the scum pipe 6 in the suction state takes in the scum S scraped by the scum skimmer 7 together with the water to be treated W from the opening 61 and discharges it outside the circular tank 2 from the discharge port 62. And the discharged scum S is separated from the water to be treated W, and the water to be treated W is returned to the previous stage.

[0032] Thereafter, when the scum skimmer 7 rotates to the position of the scum pipe 6, as shown in Fig. 4C, the striker 8 abuts against the upper bar 63 and pushes the upper bar 63 forward in the moving direction (forward rotation direction) of the shaft 3. Then, when the striker 8 pushes the upper bar 63, the scum pipe 6 reversely rotates in the axial direction from the suction state (see Fig. 4C) towards the standby state (see Fig. 4D). And the scum pipe 6 in the standby state finishes taking in the water to be treated W and the scum S, and waits until the scum skimmer 7 makes one round of the circular tank 2 and scrapes the scum S again.

[0033] Here, as for the operation of the scum pipe 6, in order to continuously and efficiently remove the scum S, it is important that the water depth dx in the intake state is within a predetermined range and that the scum pipe 6 completely returns from the intake state to the standby state (returns to the original position). For example, if the water depth dx in the intake state of the scum pipe 6 is out of the predetermined range, the amount of scum S taken into the scum pipe 6 will be too little or too much. Also, if the scum pipe 6 cannot completely return from the intake state to the standby state (return to the original position), the intake of the water to be treated W will be performed more than necessary. Thus, if a problem occurs in the operation of the scum pipe 6, it becomes difficult to continuously and efficiently remove the scum S.

[0034] As a result of the inventors' intensive studies, it was found that the problems related to the operation of the scum pipe 6 described above are caused by wear of parts due to continuous use and displacement from the suitable positions related to the component arrangement. That is, due to wear of the components involved in the operation of the scum pipe 6 and displacement from the suitable positions related to the component arrangement, as the operation of the scum pipe 6, the operation related to the contact and application of pressing force of the striker 8 to the upper bar 63 or the contact and application of pressing force of the kicker 9 to the lower bar 64 does not proceed appropriately, leading to the finding that a deviation in the tilting (rotation) angle of the scum pipe 6 is connected to the problems related to the operation of the scum pipe 6. Based on this finding, the sedimentation device 1 in the present embodiment focuses on the striker 8 that contacts the upper bar 63 and / or the kicker 9 that contacts the lower bar 64 among the components involved in the operation of the scum pipe 6, and is provided with countermeasures against problems related to the operation of the scum pipe 6. Hereinafter, an example of the structure related to the striker 8 and the kicker 9 in the present embodiment will be described with specific examples.

[0035] [Structure of the striker] FIG. 5 is a schematic explanatory view showing the structure of the striker related to the sedimentation device in the present embodiment. FIG. 5A is a side view, FIG. 5B is a front view seen from the shaft 3 side (viewpoint I-I in FIG. 5A), and FIG. 5C is a perspective view. As an example of the structure of the striker 8 in this embodiment, one having a roller structure can be mentioned (hereinafter referred to as "striker 8A"). More specifically, as shown in FIG. 5, examples of the striker 8A include those composed of a roller portion 81, a rotating shaft 82, a support portion 83, and a locking portion 84.

[0036] The roller portion 81 abuts against the upper bar 63 and may have a structure that is rotatable when abutting against and applying a pressing force to the upper bar 63, and the specific structure is not particularly limited. For example, in addition to a columnar member with a central insertion hole for the rotating shaft 82, a member having a double-tube structure composed of an inner tube and an outer tube that are slidably combined with the rotating shaft 82 omitted can be used.

[0037] Further, the support portion 83 is for attaching the roller portion 81 (and the rotating shaft 82) to the arm 71 of the scum skimmer 7 via the locking portion 84. The specific structure of the support portion 83 is not particularly limited, but as shown in FIG. 5, plate-shaped or rod-shaped members are provided at both ends of the rotating shaft 82 inserted into the center of the roller portion 81, and this member is passed through the arm 71 and attached via the locking portion 84. At this time, the locking portion 84 only needs to be one that fixes the support portion 83 to the arm 71, and the specific structure is not particularly limited. For example, joints such as bosses or fastening parts such as nuts may be used, or fixing without using parts such as welding or adhesion may be performed. Note that the support portion 83 only needs to be one that can attach the roller portion 81 (and the rotating shaft 82) to the arm 71, and is not limited to passing through the arm 71.

[0038] By using the striker 8A having a roller structure such as the roller portion 81 as the striker 8, when the striker 8A and the upper bar 63 come into contact and the striker 8A is pushed forward, the striker 8A side (roller portion 81) rotates. As a result, the load applied to the contact portion between the striker 8 and the upper bar 63 is dispersed, and friction can be reduced. That is, it becomes possible to suppress wear (lengthen the life) of the components (upper bar 63 and striker 8) involved in the operation of the scum pipe 6, suppress the occurrence of factors causing problems related to the operation of the scum pipe 6, and efficiently continue to remove the scum S.

[0039] [Structure of the kicker] FIG. 6 is a schematic explanatory view showing the structure of the kicker related to the precipitation device in the present embodiment. FIG. 6A is a top view, FIG. 6B is a side view (section II-II of FIG. 6A), and FIG. 6C is a perspective view. As an example of the structure of the kicker 9 in the present embodiment, one having a roller structure can be mentioned. More specifically, as shown in FIG. 6, as the kicker 9, one including a kicker main body portion 91 and a roller portion 92 can be mentioned.

[0040] The kicker main body portion 91 is fixed to the shaft 3 and rotates and drives the kicker 9 as the shaft 3 rotates. The means for fixing the kicker main body portion 91 to the shaft 3 is not particularly limited. For example, in addition to performing locking using a joint or fastening component, fixing by welding or adhesion can be mentioned. Further, in consideration of the load applied when contacting and applying a pressing force to the lower bar 64, it is preferable to use a reinforcing member for fixing the kicker main body portion 91.

[0041] The roller portion 92 is in contact with the lower bar 64, and it may have a structure that can rotate when contacting and applying a pressing force to the lower bar 64, and the specific structure is not particularly limited. For example, using a cylindrical member slidably combined with the kicker main body portion 91 and the like can be mentioned. In addition, the kicker 9 preferably has means for preventing the roller portion 92 from coming off the kicker main body portion 91. For example, a retaining fitting for the roller portion 92 may be provided at the end of the kicker main body portion 91.

[0042] Since the kicker 9 has a roller structure such as the roller portion 92, when the kicker 9 comes into contact with the lower bar 64 and the kicker 9 is pushed forward, the kicker 9 side (roller portion 92) rotates. As a result, the load applied to the contact portion between the kicker 9 and the lower bar 64 is dispersed, and friction can be reduced. That is, it becomes possible to suppress wear (extend the life) of the components (lower bar 64 and kicker 9) involved in the operation of the scum pipe 6, suppress the occurrence of factors causing problems related to the operation of the scum pipe 6, and efficiently continue to remove the scum S.

[0043] In the precipitation device 1 of the present embodiment, either one of the striker 8 and the kicker 9 may have the above-described roller structure, but it is more preferable that both the striker 8 and the kicker 9 have the roller structure. Thereby, in the operation of the precipitation device 1, when continuing the operation of the scum pipe 6 and repeating the suction state and the standby state, it becomes possible to effectively suppress wear (extend the life) of the components involved in the operation of the scum pipe 6, and it becomes even easier to efficiently continue scum removal.

[0044] Further, in the precipitation device 1 of the present embodiment, the countermeasure against problems related to the operation of the scum pipe 6 (means for suppressing the occurrence of factors causing problems) is not limited to the striker 8A having the above-described roller structure. Hereinafter, a precipitation device provided with a striker in another aspect will be described.

[0045] 〔Second Embodiment〕 The precipitation device according to the second embodiment is different only in that it includes a striker 8B having a structure different from that of the striker 8A having a roller structure as the striker 8 in the precipitation device 1 described above. In addition, this embodiment is the same as the first embodiment except for the structure of the striker 8, and the description thereof will be omitted.

[0046] FIG. 7 is a schematic explanatory view showing another aspect of the structure of the striker according to the precipitation device in this embodiment. FIG. 7A is a side view, and FIG. 7B is a front view (viewpoint III-III in FIG. 7A) seen from the side of the shaft 3. As an example of the structure of the striker 8B in this embodiment, one having a vertical position adjustment mechanism can be mentioned. More specifically, as shown in FIG. 7, examples of the striker 8B include those composed of a contact member 85 and a vertical position adjustment mechanism 86.

[0047] The contact member 85 is one that contacts the upper bar 63, and it may have a structure capable of applying contact and pressing force to the upper bar 63, and the specific structure is not particularly limited. For example, a rod-shaped member or a plate-shaped member can be used.

[0048] The vertical position adjustment mechanism 86 is for adjusting the vertical position of the contact member 85 that contacts the upper bar 63 in the circular tank 2. Although the specific structure of the vertical position adjustment mechanism 86 is not particularly limited, as shown in FIG. 7, support portions 86a attached to both ends of the contact member 85, a male screw portion 86b provided above the support portions 86a, a nut 86c screwed onto the male screw portion 86b, and a support base 86d fixed to the arm 71 of the scum skimmer 7 and having a horizontal plane with a through hole into which the male screw portion 86b is inserted are included. In the vertical position adjustment mechanism 86 in this embodiment, the insertion distance of the male screw portion 86b with respect to the support base 86d can be made variable. Thereby, it becomes possible to adjust the vertical position of the contact member 85 in the circular tank 2.

[0049] In the precipitation device of this embodiment, by using the striker 8B provided with the vertical position adjustment mechanism 86 as the striker 8, it is possible to correct the deviation from the suitable position regarding the component arrangement related to the operation of the scum pipe 6. More specifically, since the vertical position of the striker 8B that pushes the upper bar 63 to return the scum pipe 6 to the original position can be corrected, the operation of the scum pipe 6 can be adjusted according to the suitable water depth dx for scum S removal that may vary due to fluctuations in the water level of the water to be treated W in the circular tank 2. Also, during the design or installation stage of the precipitation device 1, or during the continuous operation process of the precipitation device 1, even if the components related to the operation of the scum pipe 6 are in a state of being displaced from the suitable position, they can be corrected to an appropriate position. Thereby, the occurrence of factors causing problems related to the operation of the scum pipe 6 can be suppressed, and the removal of scum S can be efficiently continued. In particular, by enabling position adjustment on the striker 8 side that abuts against the upper bar 63, work can be performed on the liquid surface of the circular tank 2, so there is an effect of excellent workability.

[0050] 〔Third Embodiment〕 The precipitation device according to the third embodiment is different only in that it includes a striker 8C having the structures of the strikers 8A and 8B as the striker 8 in the precipitation device 1 described above. Note that this embodiment is the same as the first embodiment except for the structure of the striker 8, and the description is omitted.

[0051] FIG. 8 is a schematic explanatory diagram showing the structure of the striker according to the precipitation device in this embodiment. FIG. 8A is a side view, and FIG. 8B is a front view seen from the shaft 3 side (viewpoint IV-IV of FIG. 8A). As an example of the structure of the striker 8C in this embodiment, one having a roller structure and a vertical position adjustment mechanism can be mentioned. More specifically, as shown in FIG. 8, as the striker 8C, one including a roller portion 81, a rotating shaft 82, and a vertical position adjustment mechanism 86 can be mentioned.

[0052] Regarding the roller part 81 and the rotating shaft 82 in the striker 8C of the present embodiment, they are the same as the description of the striker 8A mentioned above. Note that, similar to the striker 8A, the rotating shaft 82 may also be omitted in the striker 8C.

[0053] Also, regarding the vertical position adjustment mechanism 86 in the striker 8C of the present embodiment, it is the same as the description of the striker 8B mentioned above. Note that in FIG. 8, as the support part 86a, it is shown that it extends in the vertical direction similar to the striker 8B shown in FIG. 7 and supports the roller part 81 and the rotating shaft 82 instead of the contact member 85, but it is not limited thereto. For example, in view of the workability related to the attachment of the roller part 81 and the rotating shaft 82 and the strength as a member, the shape of the support part 86a may be selected.

[0054] In the precipitation device of the present embodiment, by using the striker 8C having a roller structure and a vertical position adjustment mechanism as the striker 8, it is possible to suppress the wear (long life) of the parts (the upper bar 63 and the striker 8) involved in the operation of the scum pipe 6 and, at the same time, correct the deviation from the suitable position regarding the arrangement of the parts involved in the operation of the scum pipe 6. Thereby, the occurrence of factors causing problems related to the operation of the scum pipe 6 can be suppressed, and the removal of the scum S can be efficiently continued.

[0055] Note that the above-described embodiment shows an example of the precipitation device. The precipitation device according to the present invention is not limited to the above-described embodiment, and the precipitation device according to the above-described embodiment may be modified within the range not changing the gist described in the claims.

[0056] For example, in the precipitation device of the present embodiment, it has been described that the striker 8 is fixed to the scum skimmer 7 (arm 71) and the kicker 9 is fixed to the shaft 3, but the striker 8 and the kicker 9 may be fixed to anything as long as they rotate with the rotation of the shaft 3. For example, the striker 8 may be fixed to the shaft 3, or the kicker 9 may be fixed to the scum skimmer 7.

[0057] Further, the object to which the vertical position adjustment mechanism is provided in the precipitation device of the present embodiment is not limited to only the striker 8, and a vertical position adjustment mechanism may be provided on the lower bar 64 or the kicker 9 side as well. Thereby, in addition to the striker 8 side for returning the scum pipe 6 to the standby state, the position can be adjusted also for the lower bar 64 and the kicker 9 side for putting the scum pipe 6 into the sucking state, and it is possible to adjust with high precision so as to obtain a desired rotation angle in the operation of the scum pipe 6. Note that the vertical position adjustment mechanism for the lower bar 64 or the kicker 9 side is not particularly limited, and the same mechanism as the vertical position adjustment mechanism provided for the striker 8 described above may be used. More specifically, the locking portion 64b of the lower bar 64 may be configured by a combination of a male screw portion and a nut that engages with the male screw portion, or the attachment structure of the kicker 9 (kicker main body portion 91) to the shaft 3 may be configured using a detachable member (mounting bracket).

[0058] Also, in the precipitation device of the present embodiment, when the shaft 3 is driven to rotate forward, the rotation of the lower bar by the kicker or the rotation of the kicker by the lower bar is blocked to receive the force with which the kicker presses the lower bar, and when the shaft 3 is driven to rotate reversely, a release mechanism that allows the rotation of the lower bar by the kicker or the rotation of the kicker by the lower bar and releases the force with which the kicker presses the lower bar may be provided. Thereby, when the shaft 3 is driven to rotate reversely, the pressing force from the kicker 9 is not applied to the lower bar, and the scum pipe 6 does not tilt. Therefore, the state where the opening 61 of the scum pipe 6 is below the liquid level (sucking state) does not continue more than necessary, and it is possible to prevent a decrease in water treatment efficiency.

Industrial Applicability

[0059] The precipitation device of the present invention can be used as a water treatment facility for precipitating and separating solid components from the water to be treated. In particular, it is preferably used as a precipitation device provided with a scum pipe for scum removal.

Explanation of Reference Numerals

[0060] 1 Sedimentation device, 2 Circular trough, 21 Overflow weir, 22 Trough, 23 Sludge pit, 3 Shaft, 4 Driving part, 5 Rake, 51 Sludge scraping plate, 6 Scum pipe, 61 Opening, 62 Discharge port, 63 Upper bar, 64 Lower bar, 64a Bar main body part, 64b Locking part, 7 Scum skimmer, 71 Arm, 72 Blade, 8, 8A, 8B, 8C Striker, 81 Roller part, 82 Rotation axis, 83 Support part, 84 Locking part, 85 Contact member, 86 Vertical position adjustment mechanism, 86a Support part, 86b Male screw part, 86c Nut, 86d Support base, 9 Kicker, 91 Kicker main body part, 92 Roller part, dx Water depth, M Motor, R Axis, S Scum, W Water to be treated

Claims

1. A shaft provided to extend vertically at the center of a circular groove; A drive unit for rotationally driving the shaft; A brake fixed to the shaft at the bottom of the circular groove; A scum pipe formed in a cylindrical shape extending in the radial direction of the circular groove at the liquid level of the circular groove, provided to be rotatable about an axis, having an opening for taking in scum floating on the liquid level, an upper bar extending obliquely upward when the opening faces upward, and a lower bar extending downward when the opening faces upward; A striker that contacts the upper bar by rotation of the shaft; A kicker that contacts the lower bar by rotation of the shaft, and comprising: The precipitation device, characterized in that the kicker or the striker has a roller structure.

2. A shaft provided to extend vertically at the center of a circular groove; A drive unit for rotationally driving the shaft; A brake fixed to the shaft at the bottom of the circular groove; A scum pipe formed in a cylindrical shape extending in the radial direction of the circular groove at the liquid level of the circular groove, provided to be rotatable about an axis, having an opening for taking in scum floating on the liquid level, an upper bar extending obliquely upward when the opening faces upward, and a lower bar extending downward when the opening faces upward; A striker that contacts the upper bar by rotation of the shaft; A kicker that contacts the lower bar by rotation of the shaft, and comprising: The precipitation device, characterized in that a vertical position adjustment mechanism is provided on the striker.

3. A shaft provided to extend vertically at the center of a circular groove; A drive unit for rotationally driving the shaft; A brake fixed to the shaft at the bottom of the circular groove; An opening formed in a cylindrical shape extending in the radial direction of the circular groove at the liquid level of the circular groove and provided rotatably about the axis, for taking in scum floating on the liquid surface, an upper bar extending obliquely upward when the opening faces upward, and a lower bar extending downward when the opening faces upward, a scum pipe having the same; A striker that contacts the upper bar by the rotation of the shaft; A kicker that contacts the lower bar by the rotation of the shaft, and comprising the same; The striker or the kicker has a roller structure; A precipitation device, characterized in that a vertical position adjustment mechanism is provided on the striker.

Images