JP2020175382A - Scum moving device - Google Patents

Abstract

To provide a scum moving device capable of moving scum even when a bride is formed.SOLUTION: A scum moving device 5 for moving scum floating on the water surface in a predetermined direction, which is provided with (i) a hollow body 51 extending along the direction of movement, and with a discharge port 521 for discharging fluid into an internal space S defined by the inner surface 51a of the hollow body 51, the hollow body 51 having a first right aperture 511R and a first left aperture 512L extending along the direction of movement on the side of the hollow body 51.SELECTED DRAWING: Figure 1

Description

The present invention relates to a scum moving device that moves a scum floating on a water surface in a predetermined moving direction.

Scum that hinders purification treatment is floating on the water surface of the settling basin provided in the sewage treatment facility and the headrace that distributes sewage to the settling basin. Hereinafter, the sedimentation basin and the headrace will be collectively referred to as a headwater. Leaving scum floating in a headrace or the like for a long period of time causes deterioration of sewage quality. Therefore, a scum moving device for moving the scum and a scum removing device for removing the moved scum may be provided in the headrace or the like. As this scum moving device, a device in which a plurality of nozzles are arranged above a headrace or the like and the scum is moved to the scum removing device side by the force of water discharged from the nozzles has been proposed. As such a scum moving device, those described in Patent Document 1 and Patent Document 2, for example, are known.

JP-A-2002-143843 Japanese Unexamined Patent Publication No. 2004-136244

However, the scum floating on the water surface may form a bridge between the side walls of the headrace or the like. The bridge is also called arching, and refers to a state in which a scum is hung between the side walls of a headrace or the like. When the bridge is formed, the movement of the scum is hindered. When the bridge is formed, even if the fluid is discharged from the plurality of nozzles shown in Patent Document 1 and Patent Document 2, only small holes are formed in the bridge where the fluid discharged from the nozzles directly hits. It was not possible to move the scum to the scum remover side. In addition, although the fluid discharged from the nozzles locally generates a certain amount of water flow near each nozzle, the water flow weakens as the distance from the hole in the bridge increases, making it difficult to move the scum over a long distance. ..

In view of the above circumstances, an object of the present invention is to provide a scum moving device capable of moving a scum even if a bridge is formed.

The scum moving device of the present invention that solves the above object is a scum moving device that moves a scum floating on a water surface in a predetermined moving direction.
A hollow body extending along the moving direction and
A discharge port for discharging a fluid into an internal space defined by the inner peripheral surface of the hollow body is provided.
The hollow body is characterized in that an opening extending along the moving direction is formed on a side portion of the hollow body.

Here, the discharge port may be one that discharges a fluid in the moving direction. Further, the discharge port may be arranged at the upstream end portion of the hollow body in the moving direction. In addition, the internal space may be a space in which the upper end and the lower end are closed. Further, the internal space may be a space in which the upstream end and the downstream end in the moving direction are open.

According to this scum moving device, a scum can be moved a long distance along the moving direction.

In this scum moving device, the hollow body is fixed, and in response to fluctuations in the water level, at least a part of the opening is exposed to the atmosphere and the entire opening is below the water surface. It may change state to the position submerged state.

The exposed state may be a fully exposed state in which the entire opening is exposed to the atmosphere. Further, the discharge port may discharge a mixed fluid in which a liquid and a gas are mixed.

The water level of the headrace, etc. is not constant but fluctuates. When the hollow body is placed in a position where it is constantly exposed to the atmosphere, when the water level drops, the opening is greatly separated from the water surface in the height direction, so that the scum removing device is used before the discharged fluid reaches the water surface. The momentum of the fluid toward the side is weakened. Even if the fluid with weakened momentum reaches the surface of the water, a strong water flow cannot be formed, so that the effect of moving the scum in the moving direction is weakened. On the other hand, by arranging the hollow body at a position where the state changes between the exposed state and the submerged state, the opening is not significantly separated from the water surface in the height direction in the exposed state. The fluid can reach the surface of the water while retaining the momentum of the fluid released from. Further, in the submerged state, a strong water flow accompanied by waves can be generated by the fluid discharged into the water from the opening. The strong water flow accompanied by this wave can destroy the bridge and move the scum downstream in the moving direction by the water flow.

Since the fluctuation range in the water level fluctuation is limited to a constant width, even if the exposed state is a fully exposed state in which the entire opening is exposed to the atmosphere, the opening is in the height direction in the fully exposed state. There is no significant separation from the water surface. Therefore, since the fluid reaches the water surface before the momentum of the discharged fluid is greatly weakened, a strong water flow can be formed. Further, when the discharge port discharges the mixed fluid, the mixed fluid discharged from the opening in the submerged state tends to rise toward the water surface due to the gas contained in the mixed fluid. Therefore, by discharging the mixed fluid, a stronger water flow and a higher wave can be generated on the water surface portion in the submerged state.

Further, in this scum moving device, the opening is composed of a right opening formed on the right side of the hollow body and a left opening formed on the left side of the hollow body when viewed from the upstream side in the moving direction. ,
The right opening and the left opening may be arranged alternately along the moving direction.

Since the fluid can be discharged from both the left and right sides of the hollow body, the scum can be moved even in a wide headrace or the like.

In this scum moving device, the opening is composed of a right opening formed on the right side of the hollow body and a left opening formed on the left side of the hollow body when viewed from the upstream side in the moving direction.
The right opening and the left opening may be arranged at overlapping positions in the moving direction.

The fluid discharged from both the left and right sides of the hollow body forms an island-shaped scum that is released from both the left and right side walls and is easy to move, and the island-shaped scum moves by the water flow, so that the scum on the downstream side in the moving direction is moved. It will be easier to move. In addition, the scum can be moved even in a wide headrace or the like.

The scum moving device may be provided with a supply port for supplying gas to the internal space.

In a submerged state in which the entire opening is located below the water surface, the fluid discharged from the discharge port and the gas supplied from the supply port are mixed in the internal space, and the fluid discharged from the opening is , The gas makes it easier to rise toward the water surface. Therefore, even if the hollow body is submerged to a certain depth, a strong water flow and high waves can be generated on the water surface portion.

In this scum moving device, the discharge port may have a flat shape in which the direction toward the side portion is crushed and the height is widened.

With such a shape, it is possible to prevent the discharged sewage from spreading too much toward the side immediately after the discharge, so that the amount of fluid flowing out from the opening is maintained even on the downstream side in the moving direction. It becomes easy to be done. As a result, the scum can be released from the state of being hung between the side walls in a long range along the moving direction.

Further, in this scum moving device, a plurality of the hollow bodies are provided at intervals in the moving direction.
The discharge port may be arranged at the upstream end portion in the moving direction of each of the hollow bodies.

By doing so, the scum can be moved by a long distance in the moving direction, so that it is possible to cope with a headrace or the like having a long length in the moving direction.

In this scum moving device, the hollow body may have a length along the moving direction shorter than the interval.

According to this aspect, the hollow body can be easily manufactured, and the scum moving device can be constructed at low cost.

According to the present invention, it is possible to provide a scum moving device capable of moving a scum even if a bridge is formed.

It is a top view of the headrace provided with the scum moving device corresponding to one Embodiment of this invention. FIG. 5 is a sectional view taken along the line AA of the headrace shown in FIG. (A) is a cross-sectional view taken along the line BB of the hollow body shown in FIG. 1, and FIG. 1 (b) is a cross-sectional view taken along the line CC of the hollow body shown in FIG. (A) is an enlarged view showing the part D of FIG. 2 in an enlarged manner, and (b) is a view taken along the arrow E of FIG. 4 (a). It is a top view which shows the operation in the scum moving device of this embodiment. It is a plan view similar to FIG. 1 in the headrace provided with the scum moving device of the second embodiment. It is a plan view similar to FIG. 1 in the headrace provided with the scum moving device of the third embodiment. FIG. 7 is a sectional view taken along line FF of the headrace shown in FIG. FIG. 8A is an enlarged view showing an enlarged portion G of FIG. 8, and FIG. 8B is a sectional view taken along line HH of FIG. 8A. It is a top view which shows the operation in the scum moving device of 3rd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The scum moving device according to the embodiment of the present invention is arranged in the headrace and moves the scum on the water surface of the headrace to the scum removing device side.

FIG. 1 is a plan view of a headrace provided with a scum moving device corresponding to an embodiment of the present invention. In FIG. 1, the portion below the ceiling of the headrace is shown. In addition, a part of the sedimentation basin is also shown in FIG.

As shown in FIG. 1, the headrace 1 of the present embodiment is a rectangular facility in a plan view surrounded by a left side wall 11, a right side wall 12, an upstream wall 13 and a downstream wall 14. Sewage such as sewage and rainwater treated in a sand basin or the like (not shown) flows into the headrace 1. The headrace 1 is for receiving the inflowing sewage and distributing the sewage to a plurality of settling basins 9 for inflow. The headrace 1 receives sewage from the left side in FIG. 1 (see the white arrow shown in FIG. 1). The sewage received by the headrace 1 flows between the left side wall 11 and the right side wall 12 toward the right side in FIG. Hereinafter, the upstream side of the received sewage flow is simply referred to as the upstream side, the downstream side of the sewage flow is simply referred to as the downstream side, and the direction from the upstream side to the downstream side is referred to as a movement direction. Further, the direction to the left when viewed from the upstream side (upward direction in FIG. 1) is referred to as a left direction, and the direction to the right when viewed from the upstream side (downward direction in FIG. 1) is referred to as a right direction. In addition, when the left-right direction is indicated without distinguishing between the left direction and the right direction, it is referred to as the width direction.

In the middle portion of the right side wall 12 in the height direction, an inflow port 121 for pouring the sewage in the headrace 1 into each settling basin 9 is formed for each settling basin 9. Further, each inflow port 121 is provided with an inflow door 122. The inflow door 122 opens and closes the inflow port 121 by moving up and down along the right side wall 12. By moving the inflow door 122 in the vertical direction by a drive mechanism (not shown) to change the inflow area at the inflow port 121, the amount of sewage flowing into the settling basin 9 connected to the inflow port 121 can be adjusted. ..

A scum removing device 3 and a scum moving device 5 are arranged in the headrace 1. The scum removing device 3 is provided at the downstream end of the headrace 1. The scum removing device 3 has a scum pit 31, a scum pump 32, a scum pit weir 33, and a gate 34. The scum pit 31 is a portion separated from the other portion of the headrace 1 by the scum pit weir 33. The scum pump 32 is arranged in the scum pit 31. The scum pit weir 33 is a weir having the same height as the left side wall 11 and the right side wall 12. The scum pit weir 33 has a scum swallowing port 331 formed at a predetermined height position. Further, on the upstream side of the scum swallowing port 331, a gate 34 that moves up and down along the upstream side surface of the scum pit weir 33 is arranged. This gate 34 corresponds to an example of a movable weir. The scum swallowing port 331 and the gate 34 will be described later.

The scum moving device 5 has a hollow body 51, a nozzle 52, and a nozzle pipe 53. The hollow body 51 is arranged at the center of the headrace 1 in the width direction. The hollow body 51 is a hollow elongated member, and extends from the vicinity of the upstream wall 13 to the vicinity of the scum pit weir 33 along the moving direction. The hollow body 51 of the present embodiment is formed by connecting two first pipe bodies 511 and two second pipe bodies 512 alternately along a moving direction by a flange joint 513. The upstream end 51u and the downstream end 51d of the hollow body 51 are open. However, one or both of the upstream end 51u and the downstream end 51d of the hollow body 51 may be closed.

The tip end side of the nozzle 52 is arranged in the internal space S (see FIG. 4) formed by the hollow body 51. The rear end of the nozzle 52 is connected to the nozzle pipe 53. The nozzle pipe 53 is fixed to the left side wall 11 by a fixture (not shown) installed on the left side wall 11. The sewage sucked up from the settling basin 9 is supplied to the nozzle pipe 53. However, the discharged sewage may be sucked up from other than the settling basin 9. Further, water from another pond or tap water may be used instead of sewage. Further, a mixed fluid in which a liquid and a gas are mixed may be used. When a mixed fluid is used, a bubble generator may be provided in the middle of the nozzle pipe 53. The sewage supplied to the nozzle pipe 53 is discharged from the nozzle 52 toward the internal space S.

FIG. 2 is a cross-sectional view taken along the line AA of the headrace shown in FIG.

As shown in FIG. 2, a flow rate adjusting valve 531 and an electric valve 532 are installed in the upstream portion of the nozzle pipe 53 in the sewage supply direction. The motor-operated valve 532 is opened at a predetermined time when the scum of the headrace 1 is moved in the moving direction and removed from the headrace 1. When the motorized valve 532 is opened, the flow rate of sewage adjusted by the flow rate adjusting valve 531 passes through the motorized valve 532 and the sewage is supplied to the nozzle 52.

The hollow body 51 is fixed at a predetermined position in the headrace 1 by three support members 161. Each of the three support members 161 is suspended from the ceiling 16 of the headrace 1. The support member 161 is made of a stainless steel rod. The lower end portion of each support member 161 is attached to the flange joint 513. The hanging position of the support member 161 may be shifted in the moving direction, and the lower end portion of the support member 161 may be attached to the first pipe body 511 or the second pipe body 512. Further, instead of the support member 161, a leg body that supports the hollow body 51 may be installed on the bottom surface of the headrace 1.

As shown in FIG. 2, the water level of the headrace 1 fluctuates depending on various conditions such as the weather. FIG. 2 shows the highest water level, the high water level HWL, the lowest low water level LWL, and the standard water level, the standard water level SWL. The difference between the high water level HWL and the low water level LWL is 500 mm. The standard water level SWL is a water level just between the high water level HWL and the low water level LWL, and is also the average water level in the headrace 1.

The scum swallowing port 331 formed in the scum pit weir 33 has an upper end above the high water level HWL and a lower end below the low water level LWL. A gate drive device 333 is installed on the ground portion of the headrace 1. The gate 34 moves up and down by driving the gate drive device 333 in response to a command from the control device that controls the headrace 1. The gate 34 is usually in a position to block the entire scum swallowing port 331. The gate 34 descends to a position corresponding to the water level of the headrace 1 at a predetermined time when the scum of the headrace 1 is moved in the moving direction and removed from the headrace 1. At that time, by opening the motorized valve 532, the scum floating in the headrace 1 can be moved to the scum removing device 3 side and flowed into the scum pit 31 through the scum swallowing port 331. In the present embodiment, the movable weir type scum removing device 3 in which the gate 34 moves up and down is used, but the overturning weir type scum removing device 3 and the scum gap type scum removing device 3 may be used. The scum that has flowed into the scum pit 31 is sucked up by the scum pump 32 and sent to the outside of the headrace 1.

3A is a cross-sectional view taken along the line BB of the hollow body shown in FIG. 1, and FIG. 3B is a cross-sectional view taken along the line CC of the hollow body shown in FIG. In FIGS. 3 (a) and 3 (b), the hatching and the background showing the cross section are not shown.

As shown in FIG. 3A, the first tubular body 511 constituting the hollow body 51 has a cross-sectional shape of approximately 5/6 circle having a first right opening 511R on the side portion in the right direction. That is, the cross-sectional shape of the first tubular body 511 is C-shaped. The first right opening 511R corresponds to an example of the opening. The first tubular body 511 is formed by molding a stainless steel plate having a thickness of 3 mm into an arc shape having an inner diameter of 150 mm. The upstream end and the downstream end of the first pipe body 511 are open. The first right opening 511R extends along the moving direction over the entire length of the first tubular body 511. The opening height of the first right opening 511R is 80 mm. The central height of the first right opening 511R coincides with the height of the axial center 511c of the first tubular body 511. That is, the first right opening 511R is arranged right beside the first pipe body 511. However, if a part of the first right opening 511R is at a height position that matches the height of the axial center 511c of the first tubular body 511, the first tubular body 511 is arranged so as to be rotated around the axial center 511c. It doesn't matter. In such a case, the first right opening 511R is arranged diagonally above or diagonally below the right of the first tube 511. Further, of the two first pipe bodies 511, the position of the first right opening 511R is that of the first pipe body 511 arranged on the upstream side of the hollow body 51 and the first pipe body 511 arranged on the downstream side. May be arranged at different angles about the axis 511c so as to be different. The first right opening 511R acts as a discharge port for discharging sewage discharged from the discharge port 521 (see FIG. 4) into the internal space S to the outside of the internal space S.

As shown in FIG. 3B, the second tubular body 512 has a cross-sectional shape of approximately 5/6 circle having a first left opening 512L on the left side portion. That is, the cross-sectional shape of the second pipe body 512 is a C shape with the left and right sides inverted. The first left opening 512L corresponds to an example of the opening. The second tubular body 512 is formed by molding a stainless steel plate having a thickness of 3 mm into an arc shape having an inner diameter of 150 mm. The upstream and downstream ends of the second pipe body 512 are open. The first left opening 512L extends along the moving direction over the entire length of the second tubular body 512. The opening height of the first left opening 512L is 80 mm. The center height of the first left opening 512L coincides with the height of the axial center 512c of the second tube body 512. That is, the first left opening 512L is arranged right beside the left side of the second pipe body 512. However, if a part of the first left opening 512L coincides with the height of the axial center 512c of the second tubular body 512, the second tubular body 512 may be arranged by rotating around the axial center 512c. Absent. In such a case, the first left opening 512L is arranged diagonally above the left or diagonally below the left of the second pipe body 512. Further, of the two second pipe bodies 512, the second pipe body 512 arranged on the upstream side of the hollow body 51 and the second pipe body 512 arranged on the downstream side are located at the position of the first left opening 512L. May be arranged at different angles about the axis 512c so as to be different. The first left opening 512L also acts as a discharge port for discharging the sewage discharged into the internal space S. The second tube body 512 is structurally the same as the first tube body 511, and is arranged so as to be rotated 180 degrees with respect to the first tube body 511 about the axis 512c.

The axial center 511c of the first tubular body 511 shown in FIG. 3A and the axial center 512c of the second tubular body 512 shown in FIG. 3B coincide with each other. Therefore, the inner peripheral surface 511a of the first tubular body 511 and the inner peripheral surface 512a of the second tubular body 512 are continuous in the moving direction. Hereinafter, when it is not necessary to distinguish between the axial center 511c of the first tubular body 511 and the axial center 512c of the second tubular body 512, it is referred to as the axial center 51c of the hollow body 51. When it is not necessary to distinguish between the inner peripheral surface 511a of the first tubular body 511 and the inner peripheral surface 512a of the second tubular body 512, it is referred to as the inner peripheral surface 51a of the hollow body 51. The space continuous in the moving direction across the first pipe body 511 and the second pipe body 512 is the internal space S. In other words, the internal space S is defined by the inner peripheral surface 51a of the hollow body 51. Therefore, the internal space S is a space in which the upper end and the lower end are closed and one of the left end and the right end is open.

The height of the first right opening 511R is preferably 2/3 or less and 1/5 or more of the inner diameter of the first pipe body 511. Similarly, the height of the first left opening 512L is preferably 2/3 or less and 1/5 or more of the inner diameter of the second pipe body 512. When the height of the first right opening 511R or the first left opening 512L exceeds 2/3 of the inner diameter of the first pipe body 511 or the inner diameter of the second pipe body 512, the internal space S from the discharge port 521 (see FIG. 4) described later. When the sewage is discharged to the inside, the amount of sewage discharged to the outside of the internal space S becomes too large in the upstream portion of the internal space S. Therefore, the amount of sewage discharged from the first right opening 511R or the first left opening 512L to the outside of the internal space S in the downstream portion of the internal space S may become too small. On the contrary, when the height of the first right opening 511R or the first left opening 512L is less than 1/5 of the inner diameter of the first tube 511 or the second inner diameter 512, the first right opening 511R or the first left opening The amount of sewage discharged from the 512L to the outside of the internal space S may become too small. In that case, there is a possibility that the scum cannot be moved in the moving direction.

FIG. 4A is an enlarged view showing a portion D of FIG. 2 in an enlarged manner, and FIG. 4B is a view taken along the arrow E of FIG. 2A. Note that in FIG. 4B, hatching showing a cross section is not shown.

As shown in FIGS. 4A and 4B, the tip portion of the nozzle 52 enters the internal space S formed by the hollow body 51 from the upstream end 51u of the hollow body 51. The tip portion of the nozzle 52 has an elongated hole shape in which a pipe having an inner diameter of 80 mm is flattened from above and below. The nozzle 52 can be easily manufactured because the tip portion of the round pipe is simply crushed. A discharge port 521 is formed at the tip of the nozzle 52. The sewage supplied from the nozzle pipe 53 (see FIG. 2) to the nozzle 52 is discharged from the discharge port 521 in the moving direction. The sewage discharged from the discharge port 521 corresponds to an example of a fluid. The sewage discharged from the discharge port 521 forms a water flow having a velocity corresponding to the discharge flow velocity in the internal space S, and is discharged to the outside of the internal space S from the first right opening 511R or the first left opening 512L. Further, a part of the sewage discharged from the discharge port 521 is discharged toward the downstream side from the downstream end 51d (see FIG. 1) of the hollow body 51. The nozzle 52 may be a round pipe as it is, but by forming it into a flat elongated hole shape, the sewage that passes through the nozzle 52 and is discharged from the discharge port 521 Discharge pressure can be increased. Further, the discharge port 521 may have a long flat shape in the vertical direction or the diagonal direction, but by forming the discharge port 521 in a long flat shape in the horizontal direction as shown in FIG. It is difficult to diffuse and easily diffuses in the width direction. As a result, sewage is likely to be discharged to the outside of the internal space S from the first right opening 511R and the first left opening 512L.

As shown in FIG. 4A, the discharge port 521 is arranged in the internal space S at the upstream end 51u portion of the hollow body 51. The discharge port 521 discharges sewage in the moving direction. Since the discharge port 521 is arranged in the internal space S, all the sewage discharged from the discharge port 521 can be discharged into the internal space S. Further, since the upstream end 51u of the hollow body 51 is open, when the first right opening 511R and the first left opening 512L are in a submerged state described later, the internal space S is caused by the flow of sewage discharged from the discharge port 521. The outside sewage is sucked into the internal space S from the upstream end 51u of the hollow body 51. Therefore, more sewage than the amount of water discharged from the discharge port 521 can be supplied into the internal space S. However, the discharge port 521 does not have to enter the internal space S as long as it can discharge sewage into the internal space S. For example, the discharge port 521 does not have to enter the internal space S. It may be arranged at the same position as. If the discharge port 521 is arranged on the upstream side of the internal space S and far away from the internal space S, a part of the sewage discharged toward the internal space S may not flow into the internal space S. Therefore, when arranging it on the upstream side of the internal space S, it is desirable to arrange it close to the upstream end 51u.

As shown in FIG. 4B, the center 521c of the discharge port 521 coincides with the axis 51c of the hollow body 51. The discharge direction of the sewage discharged from the discharge port 521 is the direction along the axial center 51c of the hollow body 51. The axial center 51c of the hollow body 51 and the center 521c of the discharge port 521 may be set to different positions, and the discharge direction of the sewage may be slightly different from the axial center 51c direction of the hollow body 51. However, by aligning the axial center 51c of the hollow body 51 with the center 521c of the discharge port 521 and matching the discharge direction with the axial center 51c direction, the sewage discharged from the discharge port 521 is the inner peripheral surface of the hollow body 51. It is possible to prevent the flow of discharged sewage from being weakened due to collision with 51a as much as possible. The maximum opening length of the discharge port 521 in the width direction is 117 mm, and the maximum height is 18 mm. It is desirable that the maximum height of the discharge port 521 is lower than the opening height of the first right opening 511R and the opening height of the first left opening 512L. Further, it is desirable that the discharge port 521 is arranged between the upper end and the lower end of the first right opening 511R and the first left opening 512L (see FIG. 3B) in the height direction. As a result, the sewage discharged from the discharge port 521 is likely to be discharged from the first right opening 511R and the first left opening 512L to the outside of the internal space S while maintaining the momentum when the sewage is discharged from the discharge port 521.

FIG. 5 is a plan view showing the operation of the scum moving device of the present embodiment. FIG. 5 mainly shows the action of the sewage discharged from the first pipe body. Further, the inflow port 121 and the inflow door 122 to the settling basin are not shown.

The operation when sewage is discharged from the discharge port 521 will be described with reference to FIGS. 2 and 5 and the like. When sewage is discharged from the discharge port 521 in the moving direction, the sewage generates a fluid flow in the moving direction in the internal space S (see FIG. 4). A part of the sewage discharged from the discharge port 521 into the internal space S is formed from the first right opening 511R of the first pipe body 511 as shown by a plurality of arrows pointing diagonally downward to the right in FIG. It is emitted at an angle slightly inclined to the right with respect to the moving direction. Further, another part of the sewage discharged into the internal space S is discharged from the first left opening 512L of the second pipe body 512 at an angle slightly inclined to the left in the moving direction. The action caused by the sewage discharged from the first left opening 512L is the same as the sewage discharged from the first right opening 511R, although it is plane symmetric with respect to the vertical plane passing through the axis 51c of the hollow body 51. Is omitted. The sewage in the internal space S that was not discharged from the first left opening 512L and the first right opening 511R is discharged from the downstream end of the hollow body 51 in the moving direction.

When a scum is hung between the left side wall 11 and the right side wall 12 of the headrace 1 to form a bridge, the bridge is destroyed by the sewage discharged from the first right opening 511R. In addition, the scum constituting the destroyed bridge moves in the moving direction due to the water flow generated near the water surface of the headrace 1. Since the state in which this bridge is destroyed and the scum moves differs slightly depending on the water level of the headrace 1, the state of destruction and movement of the bridge at each water level will be described in order.

As shown in FIG. 2, when the water level of the headrace 1 is at the low water level LWL, the hollow body 51 is in a fully exposed state in which the entire first right opening 511R is exposed to the atmosphere. This fully exposed state corresponds to an example of the exposed state. As shown in FIG. 5, the sewage discharged from the first right opening 511R flies in the atmosphere in the moving direction and falls toward the water surface. Then, the sewage falls on the first neighborhood region N1 which is a region near the first pipe 511 on the upstream side and the second neighborhood region N2 which is a region near the first pipe 511 on the downstream side. As a result, the scum forming the bridge in the first neighborhood region N1 and the second neighborhood region N2 collapses, and the bridge is destroyed. Each of the first neighborhood region N1 and the second neighborhood region N2 is an elongated hole-shaped region extending corresponding to the length of the first right opening 511R in the moving direction, and is shown by cross-hatching in FIG. .. The scum forming the bridge in the first neighborhood region N1 and the second neighborhood region N2 becomes a scum floating on the water surface. In addition, when the discharged sewage reaches the water surface, water flows and waves in the moving direction are formed in the vicinity of the water surface. The floating scum moves in the moving direction by the formed water flow. Then, the formed wave gradually destroys the scum mass forming the bridge around the first neighborhood region N1 and the second neighborhood region N2. Hereinafter, the mass of scum that constitutes the bridge will be referred to as a residual bridge. In particular, the residual bridge located downstream of the first neighborhood region N1 and the second neighborhood region N2 is liable to be destroyed because the water flow accompanied by the wave collides with the bridge. Further, the residual bridges on both sides of the first neighborhood region N1 and the second neighborhood region N2 in the width direction are released from the state of being hung between the left side wall 11 and the right side wall 12 by breaking the bridge. It is easy to flow down. Similarly, since the bridge is also destroyed by the sewage discharged from the first left opening 512L, the residual bridge between the first neighborhood region N1 and the second neighborhood region N2 also easily flows down. As a result, the residual bridge is destroyed along the moving direction, and the first neighborhood region N1 and the second neighborhood region N2 are connected. Further, also on the downstream side of the second proximity region N2, a flow path is formed in which the floating scum can be moved to the scum removing device 3 by breaking the bridge. The bridge near the formed flow path is also gradually destroyed by the formed wave to become a floating scum, which is drawn into the flow path side and moves in the moving direction by the water flow.

When the water level of the headrace 1 is at the high water level HWL shown in FIG. 2, the hollow body 51 is in a submerged state in which the entire first right opening 511R shown in FIG. 5 is located below the water surface. The sewage discharged into the water from the first right opening 511R creates a water flow in the headrace 1, and this water flow causes waves near the water surface. Since the assumed water level fluctuation is 500 mm as described above, the first right opening 511R is not submerged deeply in the water and is not greatly separated from the water surface even in the submerged state. In this embodiment, the upper end of the first right opening 511R does not exceed 210 mm and separate from the water surface. The water flow generated by the sewage discharged from the first right opening 511R is stronger than the water flow generated when the hollow body 51 is in the fully exposed state as described above. Also, the waves are formed higher than in the fully exposed state. When a strong stream of water with high waves collides with the bridge, the bridge is destroyed. Since the water flow accompanied by waves travels from the vicinity of the first right opening 511R at an angle slightly inclined to the right with respect to the moving direction, the water flow causes the first neighborhood region N1 and the second neighborhood in the initial stage after discharge. The bridge is destroyed in the area N2. Then, a flow path capable of moving the floating scum to the scum removing device 3 is formed along the moving direction, as in the case of the fully exposed state due to the water flow accompanied by the wave. The destroyed residual bridge becomes a scum floating on the water surface, and moves in the moving direction by the water flow in the formed flow path. As in the case of the fully exposed state, the residual bridges on both sides of the first neighborhood region N1 and the second neighborhood region N2 in the width direction are hung between the left side wall 11 and the right side wall 12 by breaking the bridge. Since it is released from the handed state, it is easy to flow down. Further, since the bridge is also destroyed by the sewage discharged from the first left opening 512L, the residual bridge between the first neighborhood region N1 and the second neighborhood region N2 can easily flow down. When the mixed fluid in which the liquid and the gas are mixed is discharged from the discharge port 521, the mixed fluid is discharged from the first right opening 511R. When the mixed fluid is discharged in a submerged state, the mixed fluid released by the gas contained in the mixed fluid tends to rise toward the water surface, so that a stronger water flow and a higher wave can be generated in the water surface portion. ..

When the water level of the headrace 1 is at the standard water level SWL shown in FIG. 2, the hollow body 51 has the lower side of the first right opening 511R shown in FIG. 5 located below the water surface and the upper side exposed to the atmosphere. It becomes semi-exposed. This semi-exposed state also corresponds to an example of the exposed state. In this semi-exposed state, sewage is discharged from the upper side of the first right opening 511R and the lower side of the first right opening 511R. Then, the sewage discharged into the atmosphere from the upper side of the first right opening 511R causes the same effect as in the fully exposed state. Further, the sewage discharged into the water from the lower side of the first right opening 511R causes the same action as in the submerged state. The amount of sewage discharged from the upper side of the first right opening 511R and the amount of sewage discharged from the lower side of the first right opening 511R are smaller than the amount discharged in the submerged state and the fully exposed state, respectively. Therefore, the action is weak when each action is viewed alone as compared with the submerged state and the fully exposed state. However, by acting both by the sewage discharged in the submerged state and the fully exposed state, the bridge is destroyed as in the submerged state and the fully exposed state, a flow path is formed, and the scum floating on the water surface is removed. It can be moved up to 3.

The flow rate of sewage discharged from the discharge port 521 is appropriately set in the range of 300 liters or more and 3000 liters or less per minute according to the opening frequency and the size of the headrace 1. If the flow rate is less than 300 liters per minute, the amount of sewage discharged from the first right opening 511R and the first left opening 512L may be too small to move the scum sufficiently. Further, if the amount exceeds 3000 liters per minute, it becomes necessary to use a large pump for sucking up sewage from a settling basin and sending it out to the discharge port 521, which makes the scum moving device 5 expensive. In addition, the amount of power consumed to drive the pump also increases. Further, when sewage exceeding 3000 liters per minute is discharged, the amount of sewage discharged into the headrace 1 increases too much, and a large amount of sewage flows into the scum pit 31 (see FIG. 2) together with the scum, and the scum concentration decreases. Therefore, the scum processing in the post-process becomes complicated.

The sewage discharge flow velocity discharged from the discharge port 521 is preferably 8 m / sec or more. At less than 8 m / sec, the water flow formed by the fluid discharged from the first right opening 511R and the first left opening 512L becomes weaker, and the residual bridge located downstream of the first near region N1 and the second near region N2. Can't be destroyed, or even if it can be destroyed, it will take too long. Further, it is desirable that the discharge pressure of the sewage discharged from the discharge port 521 is 0.05 MPa or more and 0.3 MPa or less. If it is less than 0.05 MPa, water may not be discharged from the discharge port 521 due to the water pressure applied to the discharge port 521 in the submerged state and the pressure loss in the discharge nozzle. If it is larger than 0.3 MPa, the amount of sewage discharged from the downstream end 51d of the hollow body 51 without being discharged from the first right opening 511R and the first left opening 512L increases, and the first neighborhood region N1 or the first 2 In some cases, the bridge cannot be broken in the vicinity region N2, and a flow path for moving the scum cannot be formed. Further, in order to generate a discharge pressure larger than 0.3 MPa, it is necessary to use a large pump for delivering sewage to the discharge port 521, which makes the scum moving device 5 expensive. In addition, the amount of power consumed to drive the pump also increases.

According to this embodiment, the sewage discharged from the discharge port 521 is discharged from the first right opening 511R and the first left opening 512L. The bridge formed by the scum is destroyed by the discharged sewage in a range corresponding to the length of the first right opening 511R and the first left opening 512L along the moving direction. In addition, the discharged sewage creates a stream of water with waves, destroying the residual bridge that remains around the destroyed bridge. In particular, the residual bridge on the downstream side in the moving direction where the water flow hits is easily destroyed. As a result, a flow path through which the scum can move is formed on the water surface portion. By forming the flow path, it is possible to move the scum over a long distance along the moving direction. That is, by discharging sewage from the first right opening 511R and the first left opening 512L extending in the moving direction, a water flow accompanied by waves is generated, the bridge formed in the headrace 1 is destroyed, and the scum is generated. A flow path that moves in the moving direction can be formed. Then, in the flow path, the scum can be moved by the water flow to reach the scum removing device 3, and the scum can be removed from the headrace 1. Further, since one hollow body 51 extends from the vicinity of the upstream wall 13 to the vicinity of the scum pit weir 33 and only one nozzle 52 is arranged at the upstream end 51u portion of the hollow body 51, a plurality of nozzles can be used. Compared with the conventional scum moving device arranged, it is possible to prevent the occurrence of a problem that the scum is entangled with the nozzles and the movement of the scum is blocked at the portion where each of the plurality of nozzles is provided. Further, in this embodiment, since the first right opening 511R and the first left opening 512L are alternately arranged along the moving direction, the flow of moving the scum to the downstream side on both sides of the hollow body 51 in the width direction. A road can be formed. As a result, even if the headrace 1 has a wide width to some extent, the scum can be moved in the moving direction without increasing the number of hollow bodies 51. The initial residual bridge discharged from the first right opening 511R and the first left opening 512L may adhere to either the left side wall 11 or the right side wall 12 due to the viscosity of the scum. However, unlike the state of being hung between the left side wall 11 and the right side wall 12, the residual bridge is easily attached to the left side wall 11 or the right side wall 12 because it is attached to only one of the left side wall 11 and the right side wall 12. Can be peeled off. Therefore, the residual bridge that is caught in the water flow by the fluid discharged on the upstream side or the scum flowing from the upstream side and adheres to either the left side wall 11 or the right side wall 12 can flow down with the passage of time. In this embodiment, the first right opening 511R and the first left opening 512L are alternately arranged and not arranged at the positions where they overlap in the moving direction, but the first right opening 511R and the first left opening 512L May be overlapped in a part of the moving direction.

Next, the scum moving device 5 of the second embodiment will be described. In the following description, the components having the same names as the components described so far may be described with the reference numerals used so far, and duplicate description may be omitted.

FIG. 6 is a plan view similar to FIG. 1 in the headrace provided with the scum moving device of the second embodiment.

The headrace 1 shown in FIG. 6 is about twice as long as the headrace 1 shown in the previous embodiment in the moving direction, and the scum moving device 5 is arranged in the moving direction. It differs from the two provided. As shown in FIG. 6, four settling basins 9 are connected to the headrace 1. The two scum moving devices 5 have the same configuration. The hollow body 51 of the scum moving device 5 on the upstream side extends along the moving direction from the vicinity of the upstream wall 13 to the center of the moving direction in the headrace 1. The hollow body 51 of the scum moving device 5 on the downstream side extends along the moving direction from the center of the moving direction in the headrace 1 to the vicinity of the scum pit weir 33 at a slight distance from the hollow body 51 on the upstream side. doing. A discharge port 521 (see FIG. 4) is arranged at the upstream end 51u portion of each of the two hollow bodies 51.

In the headrace 1 provided with the scum moving device 5 of the second embodiment, in addition to the effects of the above-described embodiment, two scum moving devices 5 are provided side by side in the moving direction, and the discharge ports 521 provided for each are provided. By discharging the sewage from the water, it is possible to form a flow path extending from the upstream side to the downstream side along the moving direction even if the length of the headrace 1 in the moving direction is long. Then, by the same action as the scum moving device 5 shown above, each scum moving device 5 can break the bridge to bring the scum to the scum removing device 3 and remove the scum from the headrace 1. Instead of providing the two scum moving devices 5, a hollow body 51 extending from the vicinity of the upstream wall 13 to the vicinity of the scum pit weir 33 is installed, and the first nozzle 52 that discharges sewage in the moving direction is upstream. A second nozzle 52, which is arranged near the wall 13 and also discharges sewage in the moving direction, may be arranged in the intermediate portion of the hollow body 51. That is, a scum moving device 5 in which a plurality of nozzles 52 are arranged apart from each other in the extending direction of the hollow body 51 may be used. In this case, a hole may be formed in the intermediate portion of the hollow body 51 and the second nozzle 52 may be inserted. Further, when the scum moving device 5 is provided in the headrace 1 which is longer in the moving direction, three or more scum moving devices 5 may be provided at intervals in the moving direction.

Next, the scum moving device 5 of the third embodiment will be described.

FIG. 7 is a plan view similar to that of FIG. 1 in the headrace provided with the scum moving device of the third embodiment.

The scum moving device 5 of the third embodiment shown in FIG. 7 is different from the scum moving device 5 shown in FIG. 1 in that two scum moving devices 5 are provided at intervals in the moving direction and a hollow body. The shape of the 51, the shape of the nozzle 52, and the point that the gas supply device 7 is provided are different. Another difference is that the height position where the hollow body 51 and the nozzle 52 are arranged is lower than the scum moving device 5 shown in FIG. As shown in FIG. 7, two scum moving devices 5 of the third embodiment are arranged in the headrace 1 at intervals in the moving direction. The scum moving device 5 arranged on the upstream side and the scum moving device 5 arranged on the downstream side have the same shape. Hereinafter, the description of the scum moving device 5 arranged on the downstream side may be omitted, which overlaps with the scum moving device 5 arranged on the upstream side.

The hollow body 51 of the scum moving device 5 arranged on the upstream side extends from the vicinity of the upstream wall 13 along the moving direction. The hollow body 51 is composed of a single pipe having an inner diameter of 150 mm and a length of 2 m. The upstream end 51u and the downstream end 51d of the hollow body 51 are open. A second right opening 51R formed on the right side of the hollow body 51 and a second left opening 51L formed on the left side are formed on the side portion of the hollow body 51 when viewed from the upstream side. The second right opening 51R, the left side portion, and the second left opening 51L are arranged at the same position in the moving direction and the height direction. The second right opening 51R and the second left opening 51L correspond to an example of the opening. It is desirable that the second right opening 51R and the second left opening 51L are arranged at the same positions in the moving direction, but they do not have to be completely aligned, and they are arranged at partially overlapping positions. Just do it. The second right opening 51R and the second left opening 51L will be described in detail later. The length of the hollow body 51 of the scum moving device 5 arranged on the upstream side along the moving direction is the length of the hollow body 51 of the scum moving device 5 arranged on the upstream side and the scum moving device 5 arranged on the downstream side. It is shorter than the distance from the hollow body 51. The distance between the upstream end 51u of the hollow body 51 of the scum moving device 5 arranged on the upstream side and the upstream end 51u of the hollow body 51 of the scum moving device 5 arranged on the downstream side is 10 m. Therefore, the distance between the hollow body 51 of the scum moving device 5 arranged on the upstream side and the hollow body 51 of the scum moving device 5 arranged on the downstream side is 8 m. Further, the distance between the upstream end 51u of the hollow body 51 of the scum moving device 5 arranged on the downstream side and the scum swallowing port 331 of the scum removing device 3 is also 10 m. In addition, in FIGS. 7 and 8, the distance between the hollow body 51 of the scum moving device 5 arranged on the upstream side and the hollow body 51 of the scum moving device 5 arranged on the downstream side is shown to be slightly shorter. Further, the distance between the hollow body 51 of the scum moving device 5 arranged on the downstream side and the scum swallowing port 331 of the scum removing device 3 is also shown to be slightly shorter.

FIG. 8 is a sectional view taken along line FF of the headrace shown in FIG.

As shown in FIG. 8, the hollow body 51 of the scum moving device 5 arranged on the upstream side is fixed at a predetermined position in the headrace 1 by a support member 161 suspended from the ceiling 16 of the headrace 1. .. The lower end portion of the support member 161 is fixed to the central portion of the hollow body 51 in the moving direction. When the water level of the headrace 1 is at the high water level HWL and the standard water level SWL, the hollow body 51 is in a submerged state in which the entire second right opening 51R and the entire second left opening 51L (see FIG. 7) are submerged. When the water level of the headrace 1 is at the high water level HWL, the axial center 51c of the hollow body 51 (see FIG. 9B) is at a height position 400 mm submerged from the water surface. On the other hand, when the water level of the headrace 1 is at the low water level LWL, the hollow body 51 is in a fully exposed state in which the entire second right opening 51R and the entire second left opening 51L are exposed to the atmosphere. When the water level is low LWL, the axial center 51c of the hollow body 51 is at a height position 100 mm above the water surface. Therefore, at the water level between the low water level LWL and the standard water level SWL, the hollow body 51 is semi-exposed with the lower side of the second right opening 51R and the second left opening 51L located below the water surface and the upper side exposed to the atmosphere. Become in a state.

The upstream end of the nozzle pipe 53 of the scum moving device 5 arranged on the upstream side in the sewage supply direction and the upstream end of the nozzle pipe 53 of the scum moving device 5 arranged on the downstream side in the sewage supply direction are one sewage. It is connected to the supply pipe 54. Sewage sucked up from the sedimentation basin 9 is supplied to the sewage supply pipe 54. However, the discharged sewage may be sucked up from other than the settling basin 9. Further, water from another pond or tap water may be used instead of sewage. A flow rate adjusting valve 531 and an electric valve 532 are installed in the nozzle pipe 53. When the motorized valve 532 is opened, the flow rate of sewage adjusted by the flow rate adjusting valve 531 passes through the motorized valve 532 and the sewage is supplied to the nozzle 52.

9 (a) is an enlarged view showing the G portion of FIG. 8 in an enlarged manner, and FIG. 9 (b) is a sectional view taken along the line HH of FIG. 9 (a). In FIG. 9A, the members constituting the headrace 1 are not shown. Further, in FIG. 9B, hatching showing a background and a cross section other than the discharge port 521 and the supply port 71 is not shown.

As shown in FIG. 9B, the hollow body 51 has a second right opening 51R on the right side portion (left side in FIG. 9B) and the left side portion (FIG. 9B). On the right side), it has a circular cross-sectional shape with a second left opening 51L. The internal space S is formed by the hollow body 51. The internal space S is defined by the inner peripheral surface 51a of the hollow body 51. Therefore, the internal space S is a space in which the upper end and the lower end are closed and the left end and the right end are open. The opening heights of the second right opening 51R and the second left opening 51L are 40 mm. The center heights of the second right opening 51R and the second left opening 51L coincide with the height of the axial center 51c of the hollow body 51. That is, the second right opening 51R and the second left opening 51L are arranged right beside the left and right sides of the hollow body 51, respectively. It is desirable that the second right opening 51R and the second left opening 51L are arranged at the same positions in the height direction, but they do not have to completely match. In addition, the central heights of the second right opening 51R and the second left opening 51L may be higher than the height of the axial center 51c of the hollow body 51, and may be lower than the height of the axial center 51c of the hollow body 51. May be. The second right opening 51R and the second left opening 51L are openings that are rectangular when viewed from the side surface of the hollow body 51, in which the length in the direction along the moving direction is longer than the length in the height direction. The second right opening 51R and the second left opening 51L extend along the moving direction from the upstream end of the hollow body 51 to the downstream side of 350 mm to the downstream end of the hollow body 51 to the upstream side of 50 mm. That is, the second right opening 51R and the second left opening 51L extend 1600 mm along the moving direction. The second right opening 51R and the second left opening 51L act as discharge ports for discharging the sewage discharged from the discharge port 521 into the internal space S to the outside of the internal space S. The second right opening 51R and the second left opening 51L may be formed on the entire side surface of the hollow body 51. However, in that embodiment, the hollow body 51 is divided into two, and a support member 161 for supporting the divided lower hollow body 51 is additionally required, so that the second right opening 51R or the second left opening is required. It is preferable that there is a portion where 51L is not formed. Further, if the second right opening 51R and the second left opening 51L are extended to one end of the downstream end and the upstream end of the hollow body 51, the strength of the hollow body 51 is reduced, and therefore both ends. It is desirable to provide a portion in which the second right opening 51R and the second left opening 51L are not formed.

As shown in FIG. 9A, the tip end portion of the nozzle 52 enters the internal space S formed by the hollow body 51 from the upstream end 51u of the hollow body 51. The tip portion of the nozzle 52 has an elongated hole shape in which a pipe having an inner diameter of 80 mm is flattened from the left and right. A flat-shaped discharge port 521 is formed at the tip of the nozzle 52, which is crushed in the direction toward the side of the hollow body 51 (width direction) and widens in the height direction. The maximum height of the discharge port 521 is 117 mm, and the maximum opening length of the discharge port 521 in the width direction is 18 mm. The discharge port 521 is arranged on the upstream side of the upstream ends of the second right opening 51R and the second left opening 51L, and on the downstream side of the upstream end 51u of the hollow body 51. As described above, the discharge port 521 may be arranged on the upstream side of the upstream end 51u of the hollow body 51 as long as the sewage can be discharged into the internal space S, and is arranged at the same position as the upstream end 51u. You may be. That is, the discharge port 521 may be arranged at the upstream end 51u portion of the hollow body 51. Further, the discharge port 521 may be arranged on the downstream side of the upstream ends of the second right opening 51R and the second left opening 51L. However, in that arrangement, sewage is not discharged from the upstream end portions of the second right opening 51R and the second left opening 51L, which are on the upstream side of the discharge port 521, and conversely, the ejector effect causes the outside of the internal space S to be discharged. Sewage may be sucked in from the second right opening 51R and the second left opening 51L. The sewage supplied from the nozzle pipe 53 to the nozzle 52 is discharged from the discharge port 521 in the moving direction. The sewage discharged from the discharge port 521 forms a water flow in the internal space S at a speed corresponding to the discharge flow velocity, and the internal space S is formed from the downstream end 51d of the hollow body 51, the second right opening 51R or the second left opening 51L. It is released to the outside of. In this third embodiment, since the discharge port 521 has a flat shape that is crushed in the width direction and widens in the height direction, the discharge pressure of the sewage discharged from the discharge port 521 is increased and the discharged sewage is on the side portion. It is suppressed from spreading toward. Therefore, it is possible to prevent the sewage discharged from the discharge port 521 from being discharged from the second right opening 51R or the second left opening 51L to the outside of the internal space S at once, and from the second right opening 51R or the second left opening 51L. The amount of discharged sewage can be easily maintained even on the downstream side in the moving direction. Further, a certain amount of sewage can be discharged from the downstream end 51d of the hollow body 51. By discharging sewage from the entire second right opening 51R or the second left opening 51L, the bridge can be broken in a long range along the moving direction and the scum can be released from the state of being hung between the side walls.

The gas supply device 7 is composed of a pipe extending from the atmosphere above the headrace 1 to the hollow body 51. The front end and the rear end of the pipe constituting the gas supply device 7 are open. The gas supply device 7 is fixed to the nozzle pipe 53 by a fixture (not shown). The tip portion of the gas supply device 7 enters the internal space S from the upstream end 51u of the hollow body 51. A supply port 71 for supplying gas is formed at the tip of the gas supply device 7. The supply port 71 is arranged in the vicinity of the discharge port 521. As shown in FIG. 9B, in the third embodiment, the supply port 71 is arranged near the lower end of the discharge port 521 at a position where a part of the supply port 71 overlaps with the discharge port 521 in the height direction. When sewage is discharged from the discharge port 521 toward the internal space S, air is drawn from the gas supply device 7 by the ejector effect and is supplied into the internal space S together with the sewage. The supplied gas moves in the moving direction while mixing with the sewage discharged from the discharge port 521, and moves from the downstream end 51d of the hollow body 51, the second right opening 51R or the second left opening 51L to the outside of the internal space S. It will be released. In the third embodiment, since the gas can be supplied only by using a tubular or hose-shaped gas supply device 7, the scum moving device 5 can be constructed at low cost. If it is desired to increase the amount of air to be supplied, a pump for sending air may be provided at the rear end portion of the gas supply device 7.

Further, a fine bubble water supply device for supplying fine bubble water may be provided in place of the gas supply device 7 or together with the gas supply device 7. In this case, the fine bubble water supply port is preferably arranged in the vicinity of the discharge port 521. When the sewage is discharged from the nozzle 52, the fine bubble water is drawn in by the ejector effect, so that the fine bubble water can be easily supplied into the internal space S without a pump for supply. However, fine bubble water may be stored in a water tank arranged on the ground and supplied by the head pressure, or may be supplied by using a pump. The fine bubble water is a fine bubble-containing liquid containing fine bubbles of 100 μm or less. The fine bubble water may be a liquid containing microbubbles having a diameter of more than 1 μm and 100 μm or less, or may be a liquid containing ultrafine bubbles having a diameter of 1 μm or less. Further, the fine bubble water may be a liquid containing both microbubbles and ultrafine bubbles. By supplying fine bubble water, the sewage in the headrace 1 can be moved while being washed.

FIG. 10 is a plan view showing the operation of the scum moving device according to the third embodiment. In FIG. 10, the action of the scum moving device 5 mainly arranged on the downstream side is shown. Further, the sewage supply pipe 54, the inflow port 121 to the settling basin, and the inflow door 122 are not shown.

First, at a predetermined time when the scum of the headrace 1 is removed from the headrace 1, the gate 34 is lowered to a position corresponding to the water level of the headrace 1. As a result, a flow of sewage from the scum swallowing port 331 toward the scum pit 31 is generated near the water surface, and the scum in the peripheral region N3 of the scum swallowing port 331 flows into the scum pit 31. In FIG. 10, the peripheral region N3 from which the scum is removed from the water surface by flowing into the scum pit 31 is shown by hatching drawn with a line pointing downward to the left. The step of lowering the gate 34 to allow the scum of the peripheral region N3 to flow into the scum pit 31 corresponds to an example of the inflow step.

Next, the electric valve 532 of the scum moving device 5 arranged on the downstream side is opened, and sewage is discharged from the discharge port 521 of the scum moving device 5 arranged on the downstream side in the moving direction. The discharged sewage generates a fluid flow in the moving direction in the internal space S (see FIG. 9B). The sewage discharged from the internal space S from the discharge port 521 is discharged from the left second right opening 51R and the second left opening 51L, and the downstream end 51d of the hollow body 51. The step of discharging sewage from the discharge port 521 of the scum moving device 5 arranged on the downstream side and discharging it from the hollow body 51 corresponds to an example of the downstream side discharge process. When a scum is hung between the left side wall 11 and the right side wall 12 of the headrace 1 to form a bridge, from the second right opening 51R and the second left opening 51L, and the downstream end 51d of the hollow body 51, respectively. The discharged sewage destroys the bridge. In addition, the scum constituting the destroyed bridge moves in the moving direction due to the water flow generated near the water surface of the headrace 1. The state in which this bridge is destroyed and the scum moves will be described for each water level.

When the water level of the headrace 1 is at the low water level LWL shown in FIG. 8, the hollow body 51 is in a fully exposed state in which the entire left second right opening 51R and the entire second left opening 51L are exposed to the atmosphere. Further, at the low water level LWL, the entire downstream end 51d of the hollow body 51 is also exposed to the atmosphere. As shown by a plurality of solid arrows pointing diagonally downward to the right in FIG. 10, a part of the sewage discharged into the internal space S is slightly inclined to the right with respect to the moving direction from the second right opening 51R. It is released at a certain angle and falls toward the surface of the water while flying in the atmosphere. Then, the sewage falls on the fourth neighborhood region N4, which is the region near the right side of the hollow body 51. Further, as shown by a plurality of solid arrows pointing diagonally upward to the right in FIG. 10, another part of the sewage discharged into the internal space S is directed in the moving direction from the second left opening 51L. It is released at an angle slightly inclined to the left, and it falls toward the surface of the water while flying in the atmosphere. Then, the sewage falls on the fifth neighborhood region N5, which is the left neighborhood region of the hollow body 51. Further, as shown by the two solid arrows pointing to the right in FIG. 10, of the sewage discharged into the internal space S, the sewage was not discharged from the left second right opening 51R and the second left opening 51L. The sewage is discharged from the downstream end 51d of the hollow body 51 in the moving direction. Then, the sewage falls on the downstream neighborhood region N6, which is the downstream neighborhood region of the hollow body 51. As a result, the scum forming the bridge in the fourth neighborhood region N4, the fifth neighborhood region N5, and the downstream neighborhood region N6 collapses, and the bridges in those regions are destroyed. Each of the fourth neighborhood region N4 and the fifth neighborhood region N5 is a long hole-shaped region extending corresponding to the length of the left second right opening 51R and the second left opening 51L in the moving direction, and is shown in FIG. Shown by cross-hatching. Further, the downstream neighborhood region N6 is an elongated hole-shaped region having a length corresponding to the momentum of the sewage discharged from the downstream end 51d, and is shown by hatching drawn by a line pointing downward to the right in FIG.

The scum forming the bridge in the fourth neighborhood region N4, the fifth neighborhood region N5, and the downstream neighborhood region N6 becomes a scum floating on the water surface. Further, an island-shaped scum is formed in the region sandwiched between the fourth neighborhood region N4 and the fifth neighborhood region N5. Furthermore, when the discharged sewage reaches the water surface, water flows and waves in the moving direction are formed near the water surface. The floating scum and the island-shaped scum move in the moving direction by the formed water flow. As a result, the bridges on the downstream side of the fourth neighborhood region N4, the fifth neighborhood region N5, and the downstream neighborhood region N6 are pushed in the moving direction to move to the peripheral region N3 where there is no scum, and the scum pit is moved from the scum swallowing port 331. It flows into 31. Furthermore, the formed waves gradually destroy the residual bridges that formed the bridges around the fourth neighborhood region N4, the fifth neighborhood region N5, and the downstream neighborhood region N6, and move in the direction of movement along the water flow. I will move. By leaving the motorized valve 532 open for a predetermined time, most of the scum located downstream of the vicinity of the upstream end of the second right opening 51R and the second left opening 51L of the hollow body 51 is scum pit 31 by these actions. Can be moved to.

When the water level of the headrace 1 is at the standard water level SWL or the high water level HWL shown in FIG. 8, the hollow body 51 is located entirely below the water surface of the left second right opening 51R and the entire second left opening 51L. It becomes a submerged state. Further, at the standard water level SWL or the high water level HWL, the entire downstream end 51d of the hollow body 51 is also submerged below the water surface. When submerged, the sewage discharged from the discharge port 521 into the internal space S causes an ejector effect, and the sewage outside the internal space S is sucked into the internal space S from the upstream end 51U of the hollow body 51. .. In FIG. 10, the state of the sewage sucked into the internal space S by the ejector effect is shown by a broken line arrow. The sewage sucked into the internal space S and the sewage discharged from the internal space S from the discharge port 521 are discharged from the left second right opening 51R and the second left opening 51L, and the downstream end 51d of the hollow body 51. The sewage discharged into the water from the second right opening 51R, the second left opening 51L, and the downstream end 51d of the hollow body 51 creates a water flow in the headrace 1, and this water flow causes waves near the water surface. Since the assumed water level fluctuation is 500 mm as described above, the first right opening 511R is not submerged deeply in the water and is not greatly separated from the water surface even in the submerged state. Moreover, air is supplied from the supply port 71 of the gas supply device 7 and mixes with the sewage flowing in the internal space S. Therefore, the sewage discharged from the hollow body 51 tends to rise toward the water surface due to the mixed air. Further, the water flow generated by the sewage discharged from the hollow body 51 is stronger than the water flow generated when the hollow body 51 is in the fully exposed state as described above. In addition, the waves are also formed higher than in the fully exposed state. When a strong stream of water with high waves collides with the bridge, the bridge is destroyed. The water flow accompanied by the waves generated by the sewage discharged from the second right opening 51R travels from the second right opening 51R at an angle slightly inclined to the right with respect to the moving direction. The water flow destroys the bridge in the fourth neighborhood region N4. Further, the water flow accompanied by the wave generated by the sewage discharged from the second left opening 51L travels from the second left opening 51L at an angle slightly inclined to the left with respect to the moving direction. The water flow destroys the bridge in the fifth neighborhood region N5. Further, the water flow accompanied by the waves generated by the sewage discharged from the downstream end 51d of the hollow body 51 advances in the moving direction. The water flow destroys the bridge in the downstream vicinity region N6.

Then, as in the case of the fully exposed state, floating scums and island-shaped scums are formed, and these scums move in the moving direction by the formed water flow. As a result, the bridges on the downstream side of the fourth neighborhood region N4, the fifth neighborhood region N5, and the downstream neighborhood region N6 are pushed in the moving direction to move to the peripheral region N3 where the scum has disappeared, and the scum swallowing port 331. Flows into the scum pit 31. Furthermore, the formed waves gradually destroy the residual bridges that formed the bridges around the fourth neighborhood region N4, the fifth neighborhood region N5, and the downstream neighborhood region N6, and move in the direction of movement along the water flow. I will move. In addition, at the upstream end 51u of the hollow body 51, the sewage in the vicinity is sucked by the ejector effect, so that the bridge near the upstream end 51u is also destroyed. Although it depends on the positional relationship between the second right opening 51R, the second left opening 51L, and the discharge port 521 of the hollow body 51, the ejector effect also affects the vicinity of the upstream ends of the second right opening 51R and the second left opening 51L. Sewage in the vicinity may be sucked in. By leaving the motorized valve 532 open for a predetermined time, most of the scum located on the downstream side of the vicinity of the upstream end 51u of the hollow body 51 can be moved to the scum pit 31 by these actions.

When the water level of the headrace 1 is between the low water level LWL and the standard water level SWL, the hollow body 51 has the left second right opening 51R, the second left opening 51L, and the lower side of the downstream end 51d of the hollow body 51 below the water surface. Is also located below, and the upper side may be in a semi-exposed state exposed to the atmosphere. In this semi-exposed state, sewage is discharged from the upper side of the left second right opening 51R, the second left opening 51L, and the downstream end 51d of the hollow body 51 and the lower side thereof. Then, the sewage discharged into the atmosphere from the upper side of the left second right opening 51R, the second left opening 51L, and the downstream end 51d of the hollow body 51 causes the same effect as in the fully exposed state. Further, the sewage discharged into the water from the lower side of the left second right opening 51R, the second left opening 51L, and the downstream end 51d of the hollow body 51 causes the same action as in the submerged state. By acting on these, the bridge can be destroyed as in the submerged state and the fully exposed state, and the scum floating on the water surface can be moved to the scum removing device 3.

After closing the electric valve 532 of the scum moving device 5 arranged on the downstream side, the electric valve 532 of the scum moving device 5 arranged on the upstream side is opened and the discharge port of the scum moving device 5 arranged on the upstream side is opened. Sewage is discharged from 521 in the moving direction. The step of discharging sewage from the discharge port 521 of the scum moving device 5 arranged on the upstream side and discharging it from the hollow body 51 corresponds to an example of the upstream side discharge process. As a result, the upstream of the hollow body 51 of the scum moving device 5 arranged on the upstream side is the same as when sewage is discharged from the discharge port 521 of the scum moving device 5 arranged on the downstream side in the moving direction. The scum near the end 51u or on the downstream side of the upstream end of the second right opening 51R and the second left opening 51L can be moved. The moved scum floats on the water surface at a position overlapping the hollow body 51 of the scum moving device 5 arranged on the downstream side in the moving direction, or on the water surface on the downstream side of the scum moving device 5 arranged on the downstream side.

After closing the electric valve 532 of the scum moving device 5 arranged on the upstream side, the electric valve 532 of the scum moving device 5 arranged on the downstream side is opened again to discharge the scum moving device 5 arranged on the downstream side. Sewage is discharged from the outlet 521 in the moving direction. As a result, it floated on the water surface at a position overlapping the hollow body 51 of the scum moving device 5 arranged on the downstream side in the moving direction, or on the water surface on the downstream side of the scum moving device 5 arranged on the downstream side. The scum can be moved to the scum pit 31. When a predetermined time required for the scum to move to the scum pit 31 has elapsed, the gate 34 is raised to close the scum swallowing port 331, and the electric valve 532 of the scum moving device 5 arranged on the downstream side is also closed. Then, the scum pump 32 is driven for a predetermined time to send the scum to the outside to complete the process. The electric valve 532 of the scum moving device 5 arranged on the upstream side and the electric valve 532 of the scum moving device 5 arranged on the downstream side may be opened at the same time. That is, the downstream side discharge process and the upstream side discharge process may be executed at the same time. Further, the gate 34 may be lowered to a position corresponding to the water level of the headrace 1, and at the same time, the electric valve 532 of the scum moving device 5 arranged on the downstream side may be opened. That is, the inflow step and the downstream discharge step may be executed at the same time, or the inflow step, the downstream discharge step, and the upstream discharge step may be executed at the same time.

Also in this third embodiment, it is possible to generate a water flow accompanied by waves, destroy the bridge formed in the headrace 1, and move the scum in the moving direction. Then, the scum can be removed from the headrace 1 by moving the scum by the water flow to reach the scum removing device 3. In addition, three or more scum moving devices 5 of this third embodiment may be installed side by side at intervals in the moving direction of the headrace 1.

The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the claims. For example, in the present embodiment, the scum moving device 5 is arranged in the headrace 1, but the scum moving device 5 may be arranged in the settling basin 9. Further, if the equipment generates scum on the water surface, the scum moving device 5 may be arranged in other equipment provided in the sewage treatment facility. Further, although the hollow body 51 is composed of a hollow body 51 having an arcuate cross-sectional shape, the hollow body 51 may have a polygonal cross section as long as it has an opening on the side surface. Further, although the hollow body 51 is fixed at a height that changes state even in a fully exposed state, it may be fixed at a height that changes state only in a semi-exposed state and a submerged state. Further, although the example in which the hollow body 51 is arranged at the center of the headrace 1 in the width direction is shown, the hollow body 51 may be arranged at one end of the headrace 1 in the width direction. When arranging at one end in the width direction, it is desirable to provide an opening only at the side on the other end.

According to the scum moving device 5 of each embodiment described above, the scum can be moved to the scum removing device 3 even if the bridge is formed. Although the scum moving device for scum has been described here, the same effect as that of the present embodiment can be obtained even if a floating substance other than the viscous scum is targeted.

It should be noted that even if the constituent requirements are included only in each of the descriptions of the embodiments described above, the constituent requirements may be applied to other embodiments.

5 Scum moving device 51 Hollow body 51a Inner peripheral surface 51R Second right opening 51L Second left opening 511R First right opening 512L First left opening 521 Discharge port S Internal space

Claims (8)

A scum moving device that moves a scum floating on the surface of the water in a predetermined movement direction.
A hollow body extending along the moving direction and
A discharge port for discharging a fluid into an internal space defined by the inner peripheral surface of the hollow body is provided.
The scum moving device is characterized in that the hollow body has an opening extending along the moving direction formed on a side portion of the hollow body. The hollow body is fixed, and in response to fluctuations in the water level, at least a part of the opening is exposed to the atmosphere and the entire opening is submerged below the water surface. The scum moving device according to claim 1, wherein the state changes. The opening is composed of a right opening formed on the right side of the hollow body and a left opening formed on the left side of the hollow body when viewed from the upstream side in the moving direction.
The scum moving device according to claim 1 or 2, wherein the right opening and the left opening are alternately arranged along the moving direction. The opening is composed of a right opening formed on the right side of the hollow body and a left opening formed on the left side of the hollow body when viewed from the upstream side in the moving direction.
The scum moving device according to claim 1 or 2, wherein the right opening and the left opening are arranged at overlapping positions in the moving direction. The scum moving device according to any one of claims 1 to 4, further comprising a supply port for supplying gas to the internal space. The scum moving device according to any one of claims 1 to 5, wherein the discharge port has a flat shape extending in a crushed height direction in a direction toward the side portion. A plurality of the hollow bodies are provided at intervals in the moving direction.
The scum moving device according to any one of claims 1 to 6, wherein the discharge port is arranged at an upstream end portion of each of the hollow bodies in the moving direction. The scum moving device according to claim 7, wherein the hollow body has a length along the moving direction shorter than the interval.

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