JP2015096262A - Transfer system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transfer system which settles mixture contained in a received liquid and suppresses stirring of the mixture while sufficiently moving the mixture.SOLUTION: A transfer system includes: a groove 3 formed on a bottom part 1a and opened upward; a space forming member 8 which extends along the groove 3, forms a space S2 with an upper end part 82 closed, and has a suction port 81 arranged beneath the upper end part 82 and separating from the bottom part 1a; and a discharge port 7 for discharging a fluid in the space S2. The suction port 81 opens in the groove 3, and functions as an opening for sucking mixture deposited in the groove 3 into the space S2 when the fluid is discharged from the discharge port 7. The space forming member 8 function as a passage in which the mixture sucked in the space S2 moves to a downstream side of the fluid in a discharge direction when the fluid is discharged from the discharge port 7. The groove 3 becomes narrow as closer to the opening 3a in an upper part connected to the opening 3a of the groove 3.

Description

  The present invention relates to a transfer system in which contaminants contained in a received liquid settle.

  In the sewage treatment system, sewage such as sewage or rainwater is accepted, the sand contained in the sewage is settled to the bottom of the pond, and then moved in a predetermined direction to collect the sand deposited on the pond bottom. Some sand ponds are provided to remove sand from sewage. This sand settling basin is known to have sand collecting means for moving sand accumulated on the bottom of the pond toward the downstream side in the fluid discharge direction by the flow of the fluid discharged from the discharge port. In the sand collection using this fluid, the accumulated sand may be swollen up by the discharged fluid, and how to suppress the sand soaking becomes important. Conventionally, an inclined plate inclined downward toward the downstream side in the discharge direction is disposed above the bottom of the pond at an interval along the discharge direction, and the inclined plate tries to prevent sand from rising ( For example, see Patent Document 1).

  In addition, the sewage treatment system receives water from which sand has been removed in a sand basin, settles the sludge contained in the received water at the bottom of the pond, and then collects the sludge accumulated at the bottom of the pond in a predetermined direction. Some sedimentation ponds are installed to remove the collected sludge from the sewage. Also in this sedimentation pond, what is provided with the moving means which moves the sludge accumulated in the pond bottom part toward the downstream of the discharge direction of the fluid with the flow of the fluid discharged from the discharge port is known. Since sludge has a particle size smaller than that of sand, it is easier to swell than sand, and it is more important how to suppress the scum of the sludge. Conventionally, a shield plate inclined downward toward the downstream side in the discharge direction is provided above the discharge nozzle provided at the bottom of the sedimentation basin, and the shield plate attempts to prevent sand from rising (for example, patents). Reference 2 etc.).

Japanese Patent Laid-Open No. 9-70503 Japanese Utility Model Publication No. 64-56807

  However, in the inclined plate described in Patent Document 1, the inclined plate is disposed so as to face the discharge direction, and the fluid discharged from the discharge port may be blocked, and the sand may not move sufficiently. is there. For this reason, if the discharge pressure of the discharge port is increased in order to sufficiently move the sand, the sand may be swollen along the inclined plate due to the momentum of the discharged fluid.

  In the shielding plate described in Patent Document 2, the shielding plate is disposed so as to face the discharge direction, and there is a problem similar to that of Patent Document 1.

  In addition to sedimentation basins and sedimentation basins, for example, it may be possible to move dirt and other contaminants that have flowed into reservoirs such as dam lakes in one direction and discharge collected contaminants such as sediment. However, it is preferable to move the soil while suppressing the rising of contaminants such as earth and sand deposited on the bottom of the dam lake.

  In view of the above circumstances, an object of the present invention is to provide a transfer system that has been devised to suppress the rising of contaminants while sufficiently moving the contaminants.

The transfer system of the present invention that solves the above object is a transfer system in which contaminants contained in the received liquid settle to the bottom,
A groove formed in the bottom and opening upward;
A space forming member that extends along the groove and that has a closed upper end portion and is provided with a suction port spaced from the bottom portion below the upper end portion;
A discharge port for discharging fluid into the space;
The suction port functions as an opening that opens in the groove and sucks the contaminants accumulated in the groove into the space by discharging fluid from the discharge port.
The space forming member functions as a path through which contaminants sucked into the space move toward the downstream side in the discharge direction of the fluid when the fluid is discharged from the discharge port.
The groove is characterized in that an upper portion connected to the opening of the groove becomes narrower as it approaches the opening of the groove.

A transfer system in which contaminants contained in the received liquid settle to the bottom,
A space forming member that extends along the bottom portion, forms a space in which the upper end portion is closed, and is provided with a suction port spaced from the bottom portion below the upper end portion;
A discharge port for discharging fluid into the space;
The suction port functions as an opening that sucks the contaminants accumulated in the bottom into the space by discharging fluid from the discharge port.
The space forming member functions as a path through which contaminants sucked into the space move toward the downstream side in the discharge direction of the fluid when the fluid is discharged from the discharge port.
The suction port is one in which the lower end of the space forming member is opened downward,
The space may be narrower as a lower end portion connected to the suction port approaches the suction port.

  In this transfer system, the discharge port may be located below the center of the space forming member and above the suction port.

  In this transfer system, the discharge port may have a flat shape.

Further, in this transfer system, the bottom is formed with a groove,
In the space forming member, the suction port is opened in the groove, and the height position of the upper end portion is substantially the same height as the opening of the groove or below the opening of the groove. Also good.

Further, in this transfer system, the bottom is formed with a groove,
The groove is of a shape that is cut out above the cylindrical body,
The space forming member may have a shape in which the suction port is opened in the groove and a lower portion of the cylindrical body is cut out.

In addition, the sand contained in the received water is a sand basin where the sand sinks to the bottom of the pond,
A space forming member that extends along the pond bottom, forms a space where the upper end portion is closed, and is provided with a suction port spaced from the pond bottom below the upper end portion;
A discharge port for discharging fluid into the space;
The suction port functions as an opening for sucking sand accumulated in the pond bottom into the space by discharging fluid from the discharge port,
The space forming member functions as a path in which the sand sucked into the space moves toward the downstream side in the discharge direction of the fluid when the fluid is discharged from the discharge port.
The discharge port may be a sand basin characterized by discharging fluid at a flow rate of 8 m / sec or more.

  The discharge port may discharge fluid at a discharge pressure of 0.05 MPa or more and 0.3 MPa or less.

  The discharge port may be located below the center of the space forming member and above the suction port.

  The discharge port may have a flat shape.

Moreover, the pond bottom is formed with a groove,
In the space forming member, the suction port is opened in the groove, and the height position of the upper end portion is substantially the same height as the opening of the groove or below the opening of the groove. Also good.

Moreover, the pond bottom is formed with a groove,
The groove is of a shape that is cut out above the cylindrical body,
The space forming member may have a shape in which the suction port is opened in the groove and a lower portion of the cylindrical body is cut out.

Further, the suction port is one in which the lower end of the space forming member is opened downward,
The space may be narrower as a lower end portion connected to the suction port approaches the suction port.

In addition, it is a sand basin where the sand contained in the received water sinks to the bottom of the pond,
A space forming member that extends along the pond bottom, forms a space where the upper end portion is closed, and is provided with a suction port spaced from the pond bottom below the upper end portion;
A discharge port for discharging fluid into the space;
The suction port functions as an opening for sucking sand accumulated in the pond bottom into the space by discharging fluid from the discharge port,
The space forming member functions as a path in which sand sucked into the space moves toward the downstream side in the discharge direction of the fluid when the fluid is discharged from the discharge port. It may be a sand basin.

  Here, the space forming member may have a C-shaped (arc-shaped), U-shaped, V-shaped, U-shaped or the like in cross-section, and the suction port extends along the pond bottom. A plurality of cylinders may be provided. Or the slit-shaped thing extended along the said pond bottom part may be sufficient as the said suction inlet.

  Further, the space forming member itself may be in contact with the pond bottom or may be separated from the pond bottom.

  Furthermore, the space forming member may be one in which the suction port is provided in the lower portion.

  According to this sand settling basin, fluid is discharged into the space from the discharge port, so that a pressure difference is generated between the space forming member (the space) and the outside, and the sand accumulated on the bottom of the pond is The air is sucked into the space from the suction port. Furthermore, in the space, the sucked sand moves toward the downstream side in the discharge direction by the flow of the fluid. The sand that moves in the space is unlikely to go out of the space forming member at the portion where the pressure difference occurs, and the sand is prevented from rolling up. Therefore, according to this sand settling basin, it is possible to suppress the sand soaking while sufficiently moving the sand.

Further, in the sand basin, the suction port is one in which the lower end of the space forming member is opened downward,
The space may be narrower as a lower end portion connected to the suction port approaches the suction port.

  That is, the suction port may be an opening constricted in the width direction orthogonal to the extending direction of the space forming member, and the space may be a space extending from the suction port. Since the suction port is thus narrowed, the sand that moves in the space is less likely to go out of the space, and the sand is further suppressed. Moreover, it becomes easy to maintain the flow of the fluid in the space, and the sand can be moved farther.

  In addition, the said suction inlet may be extended along the said pond bottom part.

  The space forming member may have an arc shape whose cross-sectional shape is larger than ½ (for example, a 3/4 arc shape).

  Further, in the sand basin, the discharge port may be disposed in the space, and further, the discharge port is in a direction in which the space forming member extends, that is, with the space forming member. The fluid may be discharged in a parallel direction (for example, a horizontal direction).

  By doing so, the pressure difference is more likely to occur.

  Here, the closer to the discharge port, the faster the fluid velocity, that is, the flow velocity. For this reason, when the discharge port is disposed in the space and in the vicinity of the suction port, the sand is more easily sucked from the suction port.

Moreover, in this sand basin, the pond bottom is formed with a groove,
The space forming member may be an embodiment in which the suction port is opened in the groove.

  According to this aspect, sand deposited on the pond bottom can be efficiently sucked into the space, and sand collection efficiency is improved.

  The groove may have an arc shape in cross section, and in this case, an arc shape larger than 1/2 (for example, a 3/4 arc shape) is preferable. By carrying out like this, it can suppress more that the sand deposited in the said groove | channel crawls out of a groove | channel.

Further, in the sand basin in which sand contained in the received water sinks to the bottom of the pond, the sand removal method for removing the sand deposited on the pond bottom from the sand basin,
A fluid is formed in a space forming member that extends along the pond bottom and has a closed upper end portion and is provided with a suction port spaced from the pond bottom below the upper end portion. A sand collecting step of moving the sand accumulated on the bottom of the pond toward the downstream side in the fluid discharge direction;
A discharge step of discharging the sand that has moved to the downstream side in the discharge direction by performing the sand collection step toward the outside of the sand basin,
In the sand collecting step, by discharging fluid into the space, the sand accumulated in the bottom of the pond is sucked into the space from the suction port, and the sand sucked into the space is directed downstream in the discharge direction. It may be a sand removal method characterized in that it is a step of moving.

  According to this sand removal method, it is possible to remove the sand from the settling basin by sufficiently moving the sand in the settling basin while suppressing the rising of the sand.

In addition, a transfer system that moves the contaminants in one direction at the bottom where the contaminants contained in the received liquid settled,
A space forming member in which an upper end portion forms a closed space, and a suction port spaced from the bottom portion is provided below the upper end portion;
A fluid supply pipe;
A discharge port for discharging the fluid supplied by the fluid supply pipe into the space;
The suction port functions as an opening that sucks the contaminants accumulated in the bottom into the space by discharging fluid from the discharge port.
The space forming member functions as a path through which contaminants sucked into the space move toward the downstream side in the fluid discharge direction when the fluid is discharged from the discharge port. It may be a transfer system.

  Here, the said transfer system is provided in the dam lake, and the earth and sand which settled in the bottom of this dam lake may be moved to one direction. Moreover, the said transfer system may move the metal powder produced in the factory etc. to one direction. The received liquid may be retained with the flow stopped for the time required to settle the contaminants, or may be retained at a flow rate necessary to sediment the contaminants.

  According to this transfer system, a fluid is discharged from the discharge port into the space, so that a pressure difference is generated between the space forming member (the space) and the outside, and contaminants accumulated on the bottom portion are collected. The air is sucked into the space from the suction port. Further, in the space, the sucked contaminants move toward the downstream side in the discharge direction by the flow of the fluid. Contaminants that move in the space are unlikely to go out of the space forming member at the portion where the pressure difference is generated, and the rise of the contaminants is suppressed. Therefore, according to this transfer system, it is possible to suppress the rising of the contaminants while sufficiently moving the contaminants.

In the above transfer system, the suction port is provided in a sedimentation basin where sludge settles,
It may function as an opening for sucking sludge accumulated as a contaminant at the bottom of the settling basin into the space.

  Here, the bottom part may be a pond bottom part of the settling basin, or may be a bottom part of a transfer path provided upstream of the pond bottom part and connected to a sludge pit.

Further, in the bottom portion where the contaminant contained in the received liquid has settled, the contaminant removal method for removing the contaminant deposited on the bottom portion,
A fluid is discharged into the space of the space forming member that extends along the bottom portion and forms a space in which the upper end portion is closed and is provided below the upper end portion and is separated from the bottom portion. A moving step of moving the contaminants accumulated on the bottom portion toward the downstream side in the fluid discharge direction;
A discharge step of discharging the contaminants that have moved to the downstream side in the discharge direction by performing the movement step;
In the moving step, by discharging a fluid into the space, the contaminants accumulated in the bottom portion are sucked into the space from the suction port, and the contaminant sucked into the space is directed downstream in the discharge direction. It may be a contaminant removal method characterized in that it is a step of moving.

  Here, the contaminant may be sludge, earth and sand, or metal powder. The received liquid may be retained with the flow stopped for the time required to settle the contaminants, or may be retained at a flow rate necessary to sediment the contaminants.

  According to this contaminant removal method, the contaminant can be removed by sufficiently moving the contaminant while suppressing the rising of the contaminant.

  ADVANTAGE OF THE INVENTION According to this invention, the transfer system by which the device which suppresses the rolling-up of a contaminant was made | formed can be provided, moving a contaminant sufficiently.

It is the top view which looked at the sand basin equivalent to one Embodiment of this invention from upper direction. It is AA sectional drawing of the sand basin shown in FIG. (A) is BB sectional drawing in FIG. 2, (b) is CC sectional drawing in (a). (A) is the fragmentary sectional view which expanded and showed the uppermost stream end vicinity of the trough, (b) is the fragmentary sectional view which looked at Fig.4 (a) from the right side. It is a flowchart which shows the flow of the sand removal method. It is sectional drawing which cut | disconnected the sand basin of 2nd Embodiment in the center of the width direction. It is DD sectional drawing of the sand basin shown in FIG. This It is a perspective view which shows the modification of a space formation member. It is a figure which shows the modification of an ejection outlet. It is a figure which shows the modification of the method of supporting a space formation member. It is the top view which looked at the sedimentation basin in which one Embodiment of the transfer system was provided from upper direction. It is a sectional side view of the sedimentation basin shown in FIG. It is EE sectional drawing in FIG. (A) is an enlarged view showing the G section in FIG. 13 in an enlarged manner, and (b) is an enlarged view showing the H section in FIG. 13 in an enlarged manner. It is a flowchart which shows the flow of the sludge removal method. It is sectional drawing which shows the aspect corresponding to FIG. 13 in the sedimentation basin provided with the transfer system of 2nd Embodiment. (A) is an enlarged view showing an I portion of FIG. 16, and (b) is a JJ sectional view in (a). It is the top view which looked at the sedimentation basin in which 3rd Embodiment of the transfer system was provided from upper direction. It is KK sectional drawing of the sedimentation basin shown in FIG. It is LL sectional drawing of the sedimentation basin shown in FIG. It is a flowchart which shows the flow of the 2nd sludge removal method. It is a figure which shows the modification of the method of supporting a space formation member. It is a figure which shows the modification which installed the space formation member 28 shown in FIG. 13 movably in the width direction.

  Embodiments of the present invention will be described below with reference to the drawings. A sand basin according to an embodiment of the present invention is disposed on the upstream side of a sewage treatment system, and after sedimenting sand contained in sewage or sewage such as rainwater, the sedimented sand is moved to a sand collecting pit. Remove from sewage.

  FIG. 1 is a plan view of a sand basin corresponding to an embodiment of the present invention as viewed from above, and FIG. 2 is a cross-sectional view of the sand basin shown in FIG.

  As shown in FIG. 1, the sand settling basin 1 is a rectangular pond that includes a dust remover 2, a trough 3, a sand collecting pit 4, and a pump well 5. Hereinafter, the long side direction of the sand basin 1 may be referred to as the long side direction, and the short side direction may be referred to as the width direction. The sand basin 1 shown in FIG. 1 receives sewage from the right side of the figure, and the received water slowly flows toward the left side of the figure (see the straight arrows shown in FIGS. 1 and 2). That is, the longitudinal direction of the sand basin is the direction of water flow, and in FIGS. 1 and 2, the right side of the figure is the upstream side and the left side is the downstream side.

  The dust remover 2 is for removing contaminants mixed in the sewage flowing into the sand basin 1, and is installed upstream of the trough 3. The dust remover 2 includes an endless chain 21, a plurality of rakes 22 attached to the endless chain 21 at intervals, and a filtration screen 23 that is submerged in water. The endless chain 21 is provided so as to stand obliquely on both sides in the width direction of the sand basin 1 and is wound around a ground-side sprocket 211 and a pond bottom-side sprocket 212 as shown in FIG. Yes. When the endless chain 21 is driven, the rake 22 enters and exits the water. The filtration screen 23 is disposed on the downstream side of the endless chain 21. The filter screen 23 is formed by arranging bars extending in the vertical direction at a predetermined interval (for example, 25 mm to 75 mm), and blocks the passage of contaminants having a size greater than the predetermined interval. The contaminants blocked by the filter screen 23 are lifted up by the rake 22, and the lifted contaminants are placed on a conveying means such as a belt conveyor (not shown) on the ground side.

  On the downstream side of the dust remover 2, a sand collecting pit 4 for collecting sand accumulated on the pond bottom 1a is provided. Inside the sand collecting pit 4, a sand pump 41 is provided. The sand pump 41 is disposed in the vicinity of the bottom surface of the sand collecting pit 4, and conveys the sand collected in the sand collecting pit 4 to the outside of the sand basin 1. A sand raising pipe 42 is connected to the sand raising pump 41. The sand sucked by the sand pump 41 is sent to the outside of the sand basin 1 through the sand pipe 42.

  The trough 3 is provided between the sand collecting pit 4 and the pump well 5. That is, the trough 3 is provided downstream of the sand collecting pit 4 and upstream of the pump well 5. The trough 3 is a groove provided in the basin 1a (see FIG. 2) of the sand basin 1. The pond bottom 1 a is provided with an inclined surface 6 as described later, and a trough 3 is provided so as to be connected to the inclined surface 6. The sand in the sewage that has flowed into the sand basin 1 sinks toward the pond bottom 1a and accumulates on the pond bottom 1a.

  The pump well 5 stores sewage from which sand has been removed. The pump well 5 is disposed on the most downstream side of the sand basin 1. In addition, as shown in FIG. 2, the bottom surface of the pump well 5 is the deepest part in the sand basin 1. A pumping pump 51 is provided in the pump well 5. The pump 51 moves sewage stored in the pump well 5 to the outside of the sand basin 1. A pumping pipe 52 is connected to the pumping pump 51. The sewage sucked by the pumping pump 51 is sent to a settling pond (not shown) through the pumping pipe 52. WL shown in FIG. 2 represents the surface of sewage. The position of the water surface WL varies depending on the amount of sewage flowing into the sand settling basin 1 such that the height from the bottom of the trough 3 is, for example, in the range of 1 m to 5 m.

  As shown in FIG. 1, the trough 3 is a groove provided in the center in the width direction of the sand basin 1 and extending in a predetermined direction from a position upstream of the pump well 5. That is, it extends toward the sand collecting pit 4. The downstream end of the trough 3 is connected to the sand collecting pit 4, and the sand accumulated in the trough 3 is moved to the sand collecting pit 4 by the flow of water discharged from a discharge port described later.

  The sand basin 1 shown in FIG. 1 also includes a space forming member 8 in the trough 3. The total length of the space forming member 8 is the same as the total length of the trough 3, and the space forming member 8 extends along the trough 3. A detailed description of the space forming member 8 will be described later.

  Fig.3 (a) is BB sectional drawing in FIG. In FIG. 3A, the horizontal direction in the figure is the width direction of the trough 3.

  FIG. 3A shows a lower portion of the inclined surface 6 provided on the pond bottom 1 a and the trough 3 provided so as to be connected to the inclined surface 6. As shown in FIG. 3A, the inclined surfaces 6 are provided on both sides of the trough 3 in the width direction. This inclined surface 6 is made of concrete inclined 45 degrees downward toward the trough 3, and extends in the longitudinal direction between the position upstream of the pump well 5 and the sand collecting pit 4. Yes. In addition, the inclination angle of the inclined surface 6 may be, for example, 30 degrees or 60 degrees.

  Moreover, the trough 3 is a groove | channel of about 15 m in total length with the cross-sectional shape of 3/4 circular arc, as shown to Fig.3 (a). The trough 3 is formed by bending a plate material made of stainless steel or the like, but may be formed integrally with the inclined surface 6 from concrete. The cross-sectional shape of the trough 3 is not limited to an arc shape, and may be a U shape, a V shape, or the like. The trough 3 shown in FIG. 3A has a shape in which an upper (liquid level side) 1/4 of a cylindrical body having a diameter of about 356 mm is cut out, and is open upward. Hereinafter, the portion opening upward is referred to as the opening 3 a of the trough 3. Of the space S1 in the trough 3, the upper end portion 3b connected to the upper end opening 3a becomes narrower as it approaches the opening 3a. That is, the opening 3a of the trough 3 is an opening narrowed in the width direction orthogonal to the extending direction of the trough.

  The sand contained in the sewage flowing into the sand basin 1 sinks to the pond bottom 1a in the course of the sewage flowing downstream, but tends to accumulate on the pond bottom 1a upstream of the sand basin 1. Among the sand that has settled on the pond bottom 1 a, the sand that has settled on the inclined surface 6 further flows down toward the trough 3 along the inclined surface 6 and enters the inside of the trough from the opening 3 a of the trough 3. Therefore, the sand that has settled on the pond bottom 1 a is first collected in the trough 3.

  The space forming member 8 shown in FIG. 3A has a 3/4 arc cross-sectional shape. The space forming member 8 is formed by forming a stainless steel plate having a thickness of 4 mm into a circular arc cross section. The space forming member 8 shown in FIG. 3A has a shape in which a lower part (pond bottom side) 1/4 of a cylindrical body having a diameter of about 156 mm is cut out, and opens downward. That is, the lower end of the space forming member 8 is opened downward, and this opened portion is hereinafter referred to as a suction port 81. The suction port 81 is an opening having a length L of 80 mm or more in the width direction of the trough 3, and is separated from the inner peripheral wall of the trough 3. The space forming member 8 partitions the space in the trough 3, and forms a space S2 in which a portion above the lower end is closed. The upper end portion 82 of the space forming member 8 is closed, but has an arc shape and is inclined downward. The sand also settles on the space forming member 8, but since it has an arc shape, it is difficult for the sand to accumulate, and the sand that has settled on the space forming member 8 passes through the arc-shaped side surface 80, and becomes trough 3. It becomes easy to flow down toward the bottom part 31. Further, due to the arc-shaped side surface 80, the space S <b> 2 becomes narrower as the lower end portion connected to the suction port 81 approaches the suction port 81.

  Here, as shown in FIG. 1 and FIG. 2, the support plate member 91 is spanned in the width direction of the trough 3 at the upper end of the trough 3 every about 5 m. Both ends of the support plate member 91 are fixed to the inclined surface 6, and the opening 3 a of the trough 3 is covered by the support plate member 91 at the place where the support plate member 91 is installed. The length in the trough extending direction is about 200 mm, and it does not matter that sand accumulates on the support plate member 91. In addition, the length of about 200 mm greatly reduces the possibility that string-like contaminants (for example, hair and vinyl strings) will wind around the support plate member 91.

  In the space forming member 8 shown in FIG. 3A, the upper end portion 82 is supported by the support plate member 91. Therefore, the height position of the upper end portion 82 of the space forming member 8 is substantially the same height position as the opening 3 a of the trough 3. In the present embodiment, when viewed in the height (depth) direction, the radial center of the space forming member 8 is shifted upward from the radial center 3 c of the trough 3. When viewed in the width direction, the radial center of the space forming member 8 coincides with the radial center 3 c of the trough 3. Therefore, the gap W between the trough 3 and the space forming member 8 is secured at 80 mm or more even at the narrowest position. As described above, the filtration member (here, the filtration screen 23) is installed on the upstream side, and the gap W between the trough 3 and the space forming member 8 is the maximum length of the contaminants that pass through the filtration member (here Then, it is preferable that the mesh width of the screen is longer than 75 mm in order to prevent the contaminants that have passed through the upstream filtration member from clogging the gap W.

  Further, the space S2 in the space forming member 8 is provided with a discharge port 7 for discharging fluid into the space S2. The discharge port 7 has a long hole shape in which the tip of a pipe-like water supply pipe 71 having a diameter of less than 50 mm is flattened. The maximum opening length in the lateral direction (trough width direction) of the discharge port 7 is about 60 mm. By making the discharge port 7 in such a flat shape, it is possible to ensure a wider range in which the flow velocity is higher than that of a perfect circle shape. The water supply pipe 71 penetrates the inclined plate 6 from the back side of the inclined plate 6, extends along the support plate member 91 in the width direction of the trough 3, and bends downward at the center in the width direction of the trough 3. Passes through the support plate member 91 and the space forming member 8 and enters the space S2.

  FIG.3 (b) is CC sectional drawing in the same figure (a). In FIG. 3B, the horizontal direction of the figure is the direction in which the trough 3 extends, the right side of the figure is the upstream side (sand collecting pit 4 side), and the left side is the downstream side (pump well 5 side). In addition, an axis 8c of the space forming member 8 passing through the center in the radial direction of the space forming member 8 is indicated by a one-dot chain line.

  A portion 711 of the water supply pipe 71 that has entered the space S2 extends downward beyond the radial center of the space forming member 8 and is higher than the radial center 3c of the trough 3 (see FIG. 3A). It is bent horizontally toward the upstream side (sand collecting pit 4 side). That is, a rectangular anti-winding plate 95 is erected on the upper end of the space forming member 8, and a portion 711 of the water supply pipe 71 that enters the space S <b> 2 is a vertical edge of the anti-winding plate 95. It extends downward along 951, and then extends upstream along a lateral edge 952 of the anti-winding plate 95. The winding preventing plate 95 prevents the string-like contaminants from being wound around the portion 711 of the water supply pipe 71 that has entered the space S2. The portion of the water supply pipe 71 that extends to the upstream side extends beyond the anti-winding plate 95, and the discharge port 7 is located upstream of the anti-winding plate 95.

  The discharge port 7 of the present embodiment is located below the center of the space forming member 8 in the radial direction and above the suction port 81. Water is discharged from the discharge port 7 in parallel or substantially in parallel with the axis 8c of the space forming member 8. That is, water is discharged in a horizontal direction or a substantially horizontal direction (see a right-pointing arrow in FIG. 3B).

  The discharge port 7 shown in FIG. 3 is provided at the most upstream side, that is, the position closest to the sand collecting pit 4.

  By discharging water from the discharge port 7 into the space 2 of the space forming member 8, a pressure difference is generated between the space forming member 8 (space S 2) and the outside, and accumulated in the trough 3 (space S 1). The sand is sucked into the space S2 from the suction port 81 as indicated by the curved arrow shown in FIG. Furthermore, in the space S <b> 2 of the space forming member 8, the sucked sand moves toward the sand collecting pit 4 side by the flow of water discharged from the discharge port 7. As shown in FIG. 3, the suction port 81 is an opening constricted in the width direction (a direction orthogonal to the extending direction of the space forming member 8), and the space S <b> 2 is a space expanded from the suction port 81. . Since the suction port 81 is thus narrowed, the sand that moves in the space S2 is less likely to go out of the space S2, and the sand scooping up is further suppressed. Moreover, it becomes easy to maintain the flow of water in the space S2, and the sand can be moved farther.

  The structure of the discharge port 7 in the support plate member 91 described above is the same in any support plate member 91 provided at the upper end of the trough 3. The discharge port 7 is also provided in the downstream end wall 36 of the trough 3. Hereinafter, the discharge port 7 provided in the downstream end face wall 36 of the trough 3 is referred to as a downstream discharge port, the discharge port 7 in the downstream support plate member 91 shown in FIGS. 1 and 2 is referred to as an intermediate discharge port, and the upstream side. The discharge port 7 (discharge port 7 shown in FIG. 3) in the support plate member 91 is sometimes referred to as an upstream discharge port.

  FIG. 4A is an enlarged partial sectional view showing the vicinity of the most upstream end of the trough. In FIG. 4A, the right side of the figure is the upstream side, and the left side of the figure is the downstream side.

  As shown in FIG. 4A, a plate-like downstream end wall 36 is attached to the end surface that becomes the most downstream end of the trough 3.

  FIG. 4B is a partial cross-sectional view of FIG. 4A viewed from the right side. That is, FIG. 4B is a view of the downstream end face wall 36 viewed from the upstream side, and the back side of the paper surface is the downstream side.

  FIG. 4B shows the downstream discharge port 7 provided on the downstream end face wall 36. Further downstream of the downstream discharge port 7, an L-shaped pipe 77 that forms an empty chamber 78 (see FIG. 5A) connected to the downstream discharge port 7 is provided. The L-shaped pipe 77 is an L-shaped pipe in plan view, and is connected to a supply pipe (not shown) that supplies water. The direction of the flow of the water that has flowed into the vacant chamber 78 changes to the downstream side in the vacant chamber 78, and water is discharged from the downstream discharge port 7 in the horizontal direction or the substantially horizontal direction. The position in the trough width direction where the downstream discharge port 7 is provided is the same position as the position in the trough width direction where the discharge port 7 shown in FIG. 3 is provided. Further, the height position where the downstream discharge port 7 is provided is also the same position as the height position where the discharge port 7 shown in FIG. 3 is provided.

  The sand basin 1 of the present embodiment is provided with three discharge ports 7 including a downstream discharge port, an intermediate discharge port, and an upstream discharge port. The discharge flow rate of water at any of the discharge ports 7 is 8 m / sec. The above is preferable. If the speed is less than 8 m / sec, the flow velocity becomes insufficient, and the sand may not be moved a predetermined distance in relation to the water pressure. If the sand cannot be moved by a predetermined distance, a large number of discharge ports are required in the sand moving direction, and the number of pipes to the discharge port increases, which makes the apparatus complicated and uneconomical. Moreover, the discharge pressure of water in each discharge port 7 is 0.05 MPa or more and 0.3 MPa or less.

  According to the sand settling basin 1 of the present embodiment described above, it is possible to suppress sand sanding while sufficiently moving the sand.

  Then, the sand removal method which removes the sand deposited on the pond bottom part 1a of the sand basin 1 of this embodiment from the sand basin 1 is demonstrated.

  FIG. 5 is a flowchart showing the flow of the sand removal method.

  When the sewage flowing into the sand basin 1 passes through the dust remover 2 shown in FIG. 2, contaminants mixed in the sewage are removed. The sewage that has passed through the dust remover 2 passes the sand collection pit 4, reaches the upstream end of the trough 3, and further flows in the extending direction of the trough 3. While the sewage flows through the upstream portion of the trough 3, much of the sand contained in the sewage sinks to the pond bottom 1 a of the sand basin 1. Some sand settles in the sand collecting pit 4 and some sand settles on the inclined surface 6, and the sand settled on the inclined surface 6 flows down further toward the trough 3 along the inclined surface 6. The sand that has settled down to the upper end portion 82 of the space forming member 8 flows down toward the bottom 31 of the trough 3 along the arc-shaped side surface 80 of the space forming member 8. Thus, sand accumulates in the space S1 of the trough 3.

  In the sand removing method in the present embodiment, first, the sand pump 41 shown in FIGS. 1 and 2 is driven, and the sand in the sand collecting pit 4 is removed from the sand collecting pit 4 before performing the sand collecting step described later. (Step S1). The sand accumulated in the sand collection pit 4 at this stage is mainly sand that has settled in the sand collection pit 4 and accumulated in the sand collection pit 4 among the sand in the sewage flowing into the sand basin 1.

  Next, with the sand pump 41 driven, 1500 liters of water per minute is discharged for 3 minutes under water from only the upstream discharge port 7 shown in FIG. 3 among the three discharge ports 7 (step S2). . In this step S <b> 2, water is discharged from the space S <b> 1 of the trough 3 into the space S <b> 2 partitioned by the space forming member 8. As water is discharged from the upstream discharge port 7 into the space 2, a pressure difference is generated between the space forming member 8 (space S 2) and the outside, and accumulated in the upstream portion of the trough 3 (space S 1). Sand is sucked into the space S2 from the suction port 81 (see the curved arrow shown in FIG. 3A). Further, in the space S <b> 2 of the space forming member 8, the sucked sand moves toward the sand collecting pit 4 by the flow of water discharged from the upstream discharge port 7. The sand that moves in the space S2 of the space forming member 8 is unlikely to go out of the space forming member 8 at the portion where the pressure difference is generated, and the sand is prevented from rolling up. Thus, the sand accumulated in the upstream portion of the trough 3 moves in the space S2 of the space forming member 8, and eventually reaches the sand collecting pit 4. The sand that has reached the sand collecting pit 4 is transported to the outside of the settling basin 1 by the sand pump 41 that has started driving in the previous step S1, and the sand from the settling basin 1 is removed. The removal of sand here corresponds to an example of the discharge process.

  Next, the discharge of water from the upstream discharge port 7 is stopped, and this time, 1500 liters of water per minute is discharged underwater for 3 minutes only from the intermediate discharge port 7 among the three discharge ports 7 (step S3). . The driving of the sand raising pump 41 is continued even during the execution of step S3. In step S3, similarly to step S2, by discharging water into the space S2 of the space forming member 8, a pressure difference is generated between the space forming member 8 (space S2) and the outside, and this time the inside of the trough 3 ( Sand accumulated around the intermediate discharge port 7 in the space S1) is sucked into the space S2 again from the suction port 81. Further, the sucked sand moves in the space S2 of the space forming member 8 toward the upstream discharge port 7 shown in FIG. 3 by the flow of water discharged from the intermediate discharge port 7, and reaches the periphery of the upstream discharge port 7. To reach. Since the momentum of water from the intermediate discharge port 7 decreases around the upstream discharge port 7, the sand that has reached the periphery of the upstream discharge port 7 falls from the suction port 81 toward the bottom 31 of the trough 3, and Return to the space S1 of the trough 3. That is, sand accumulates around the upstream discharge port 7 in the trough 3 (space S1).

  Next, the discharge of water from the intermediate discharge port 7 is stopped, and 1500 liters of water per minute is discharged from the upstream discharge port 7 shown in FIG. Step S4). Also in this step S 4, the sand accumulated around the upstream discharge port 7 in the trough 3 (space S 1) is sucked into the space S 2 from the suction port 81, and the sucked sand moves toward the sand collecting pit 4. It moves in S2 and eventually reaches the sand collecting pit 4. Even during the execution of step S4, the sand pump 41 continues to be driven, and the sand that has reached the sand collecting pit 4 is removed from the sand basin 1 by the sand pump 41. That is, sand removal by the sand pump 41 corresponding to an example of the discharging process is also performed here.

  This time, the discharge of water from the upstream discharge port 7 is stopped, and 1500 liters of water per minute is discharged for 3 minutes underwater from only the downstream discharge port 7 among the three discharge ports 7 (step S5). Even during the execution of step S5, the driving of the sand pump 41 is continued. In step S5, similarly to steps S2 to S4, by discharging water into the space S2 of the space forming member 8, a pressure difference is generated between the space forming member 8 (space S2) and the outside, and the trough 3 ( Sand accumulated around the downstream discharge port 7 of the space S1) is sucked into the space S2 from the suction port 81. Further, the sucked sand moves in the space S <b> 2 of the space forming member 8 toward the intermediate discharge port 7 by the flow of water discharged from the downstream discharge port 7 and reaches the periphery of the intermediate discharge port 7. Since the momentum of water from the downstream discharge port 7 decreases in the vicinity of the intermediate discharge port 7, the sand that has reached the periphery of the intermediate discharge port 7 descends from the suction port 81 toward the bottom 31 of the trough 3, Sand accumulates around the intermediate discharge port 7 in the space 3 (space S1).

  Subsequently, the discharge of water from the downstream discharge port 7 is stopped, and 1500 liters of water per minute is discharged from the intermediate discharge port 7 only for 3 minutes under water as in step S3 (step S6). Even during the execution of step S6, the driving of the sand pump 41 is continued. Also in step S6, the sand accumulated around the intermediate discharge port 7 in the trough 3 (space S1) is sucked into the space S2 from the suction port 81, and the sucked sand is directed toward the upstream discharge port 7 in the space S2. The sand moves and the sand accumulates around the upstream outlet 7 in the trough 3 (space S1).

  Next, the discharge of water from the intermediate discharge port 7 is stopped, and 1500 liters of water per minute is discharged under water for 3 minutes only from the upstream discharge port 7 shown in FIG. (Step S7). Also in this step S 7, the sand accumulated around the upstream discharge port 7 in the trough 3 (space S 1) is sucked into the space S 2 from the suction port 81, and the sucked sand moves toward the sand collecting pit 4. It moves in S2 and eventually reaches the sand collecting pit 4. Even during the execution of step S7, the driving of the sand raising pump 41 is continued, and the sand that has reached the sand collecting pit 4 is removed from the sand basin 1 by the sand raising pump 41. That is, sand removal by the sand pump 41 corresponding to an example of the discharging process is also performed here. Further, the sand pump 41 continues to be driven for a predetermined time after the discharge of the water from the upstream discharge port 7 is completed, and the sand removal corresponding to an example of the discharging process is continuously performed.

  Thus, the sand contained in the received water gathers in the sand collecting pit 4 through the transfer in the space S2 of the space forming member 8 in six stages. Steps S2 to S7 described above correspond to the sand collecting step. This sand collection step does not need to be performed after draining the water from the settling basin 1 and reducing or eliminating all the water from the settling basin 1, and is performed in a state where sewage is continuously received in the settling basin. The fluid discharged from the discharge port 7 in the sand collecting step may use sewage received in the sewage treatment plant, but may be other fluids.

  When the predetermined time elapses, the sand pump 41 that has started driving in step S1 is stopped (step S8). When the predetermined time elapses, or when sand accumulates in the sand collecting pit 4 to some extent due to the sedimented sand. Step S1 is performed again. As described above, Steps S1 to S8 are repeatedly performed after the acceptance of sewage is started.

  In the above description, the driving of the sand pump 41 is continued from the start in step S1 until it is stopped in step S8, but is stopped when the sand in the sand collecting pit 4 is reduced to a certain amount. Alternatively, the driving of the sand pump 41 may be stopped during the execution of step S3, step S5 to step S6.

  According to the sand removal method of the present embodiment, the sand can be sufficiently moved in the sand basin 1 while the sand is prevented from rolling up, and the sand can be removed from the sand basin. Moreover, in the sand removal method of this embodiment, sand flows in into the pump well 5 arrange | positioned in the most downstream side of the sand basin 1 by making the sand transfer direction into the direction which goes to an upstream from the downstream. Is preventing. That is, in this embodiment, a sand collection point (sand collection pit 4 in this embodiment) is provided on the downstream side in the sand transfer direction (corresponding to the upstream side of the sand settling basin 1 in this embodiment), and the sand transfer direction upstream side. A sewage discharge point (pump well 5 in this embodiment) is provided in the present embodiment (corresponding to the downstream side of the sand basin 1).

  Next, the sand basin 1 of 2nd Embodiment is demonstrated. In the following description, components having the same names as the names of the components described so far will be described with the reference numerals used so far, and redundant descriptions may be omitted.

  FIG. 6 is a cross-sectional view of the sand basin of the second embodiment cut at the center in the width direction. Also in FIG. 6, the right side of the figure is the upstream side and the left side is the downstream side.

  The sand basin 1 shown in FIG. 6 is different from the sand basin 1 shown in FIG. The sand settling basin 1 shown in FIG. 6 has an upstream trough 3 ′ on the upstream side of the sand collecting pit 4, and a downstream trough 3 ″ on the downstream side of the sand collecting pit 4. Both the upstream trough 3 ′ and the downstream trough 3 ″ are shorter than the trough 3 shown in FIG. 1 and the like, and these troughs 3 ′ and 3 ″ are not provided with a support plate member 91. Then, the space forming member 8 (not shown) is disposed in the trough 3 with the upstream end supported by the upstream end face wall 36 and the downstream end supported by the concrete forming the sand collecting pit 4.

  The dust remover 2 that is the same as the dust remover 2 shown in FIG. 2 is installed further upstream than the upstream trough 3 ′, but is not shown in FIG. 6.

  FIG. 7 is a DD cross-sectional view of the sand basin shown in FIG. 6. In FIG. 7, the horizontal direction in the figure is the trough width direction.

  A sand basin 1 according to the second embodiment is a pond in which a pond bottom 1a of a pond having a rectangular cross section is repaired to form an inclined surface 6, an upstream trough 3 ', and a downstream trough 3' '. In FIG. 7, the part of the pond bottom 1a that has been repaired by concrete is shown by cross hatching.

  As shown in FIG. 7, two downstream troughs 3 ″ are arranged in the width direction, and two upstream troughs 3 ′ are also arranged in the width direction. Therefore, in the sand basin 1 of the second embodiment, a total of four troughs are provided. By arranging the troughs side by side in the width direction, when the pond bottom part 1a is repaired, the amount of filling the pond bottom part 1a with concrete is reduced, and a decrease in the capacity for receiving sewage in the sand basin 1 can be suppressed. A space forming member 8 is provided in each trough.

  Then, the modification of the sand basin 1 demonstrated so far is demonstrated.

  FIG. 8 is a perspective view showing a modification of the space forming member. FIG. 8 is a view showing a state when the space forming member 8 is viewed obliquely from the sand collecting pit 4 side. In FIG. 8, the same components as the support plate member 91, the water supply pipe 71, the anti-winding plate 95, and the discharge port 7 shown in FIG. 3 are shown.

  A space forming member 8 shown in FIG. 8 is a cylindrical pipe member. The space forming member 8 is disposed on the flat pond bottom 1a where the trough 3 is not provided, and the lower end 83 of the space forming member 8 is in contact with the pond bottom 1a. A plurality of suction ports 81 are arranged in parallel in the extending direction of the space forming member 8 on both sides in the width direction of the space forming member 8. Each suction port 81 is formed by cutting a circumferential surface of a cylindrical pipe into a vertically long shape, and is provided at an intermediate portion in the vertical direction of the space forming member 8. Each suction port 81 is separated from the pond bottom 1a.

  Note that the suction port 81 may have a single slit shape connected to the extending direction on one side in the width direction of the space forming member 8. Further, the space forming member 8 is not limited to a cylindrical shape or a cross-sectional shape having an arc shape, and if the upper end portion is closed, the cross-sectional shape is a U shape, a V shape, or a U shape. Etc.

  Moreover, although the discharge port 7 of 1st Embodiment was all a thing of a flat long hole shape, it is not restricted to this shape. Furthermore, the arrangement position of the discharge port 7 is not limited to the position shown in FIG.

  FIG. 9 is a diagram illustrating a modified example of the discharge port. In FIG. 9, the horizontal direction of the figure is the width direction of the trough 3.

  Each of the discharge ports 7 shown in FIG. 9 has a perfect circle shape. The discharge port 7 shown in FIG. 5A is provided at a position that coincides with the radial center 8 c of the space forming member 8. The discharge port 7 shown in FIG. 5B is provided on the inner peripheral wall of the upper end portion 82 of the space forming member 8. Therefore, the space forming member 8 is provided above the center in the radial direction. The discharge ports 7 shown in FIGS. 2B and 2C protrude in the horizontal direction toward the downstream side. The discharge port 7 shown in FIG. 5C is provided at the lower end of the inner peripheral wall of the side surface 80 of the space forming member 8. That is, it is disposed on both sides of the suction port 81. A water supply pipe (not shown) connected to the discharge port 7 shown in FIGS. 2B and 2C is fixed to the inner peripheral wall of the side surface 80 of the space forming member 8 and extends along the inner peripheral wall. The discharge port 7 shown in FIG. 5C also protrudes toward the downstream side, but this discharge port 7 is installed slightly upward and slightly toward the center side.

  As shown in FIG. 3A and FIG. 9, the discharge port 7 does not necessarily have to be installed in the space 2 of the space forming member 8, but rather than the space forming member 8 (suction port 81). What is necessary is just to install in the space 2 of the space formation member 8 and to discharge the fluid diagonally upward.

  FIG. 10 is a diagram illustrating a modified example of how to support the space forming member. 10A, the horizontal direction of the figure is the width direction of the trough 3, as in FIG. In FIG. 10 (b), as in FIG. 3 (b), the left-right direction in the figure is the direction in which the trough 3 extends, the right side in the figure is the upstream side (sand collecting pit 4 side), and the left side is downstream. Side (pump well 5 side).

  In the space forming member 8 shown in FIG. 3A, the upper end portion 82 is supported by the support plate member 91. However, the space forming member 8 shown in FIG. 10A has a suction port 81 (FIG. 3B). The lower ends 83 on both sides of the reference are supported by the support base 92. The support base 92 is made of concrete provided at the bottom 31 of the trough 3. The support base 92 is formed at a position of the extending trough 3 where the support plate member 91 is provided. As shown in FIG. 5B, the support base 92 has an upstream inclined surface 921 and a downstream inclined surface 922, and a support portion 923 between the upstream inclined surface 921 and the downstream inclined surface 922. A lower end 83 of the space forming member 8 is supported by the support portion 923. As shown in FIG. 5A, a horizontal plane 9231 is provided at the center in the width direction of the support portion 923, and both sides of the horizontal plane 9231 are inclined downward toward the trough 3. Further, as shown in FIG. 5B, the water supply pipe 71 extends upward from below the support portion 923, and the water supply pipe 71 penetrates the horizontal plane 9231 and is bent upstream and is placed on the horizontal plane 9231. In addition, a discharge port 7 facing the upstream side is formed. As shown in FIG. 5A, the discharge port 7 is also a flat long hole.

  The shape and size of the space forming member 8 shown in FIG. 10 (a) is the same as the shape and size of the space forming member 8 shown in FIG. 3 (a), and has a 3/4 arc cross-sectional shape. is there. The radial center 8 c of the space forming member 8 whose lower end 83 is supported by the support base 92 coincides with the radial center 3 c of the trough 3.

  In the modification shown in FIG. 10, the discharge port 7 is located below the radial center 3 c of the trough 3. Further, the upper end portion 82 of the space forming member 8 is located below the opening 3 a of the trough 3.

  The upper end portion 82 of the space forming member 8 may be positioned above the opening 3 a of the trough 3, but the sand accumulated in the space S 1 in the trough 3 is efficiently put into the space S 2 of the space forming member 8. In order to inhale well, the inlet 81 needs to be located below the opening 3a of the trough 3.

  Moreover, as shown in FIG. 8, the trough 3 may not be provided in the pond bottom part 1a, but the pond bottom part 1a may be set as a flat surface, and the space formation member 8 may be installed movably in the pond width direction. By doing so, each time the space forming member 8 is slid in the pond width direction, water can be discharged from the discharge port 7 and the sand can be transferred to the downstream side over a wide width direction region.

  Next, the sedimentation basin provided with the transfer system will be described. The sedimentation basin is located on the downstream side of the sedimentation basin in the sewage treatment system, accepts the sewage from which sand has been removed by the sedimentation basin, settles the sludge contained in the received sewage, and then sinks the sedimented sludge into the sludge pit. Is removed from the sewage.

  FIG. 11 is a plan view of the sedimentation basin provided with the transfer system as viewed from above, and FIG. 12 is a side sectional view of the sedimentation basin shown in FIG.

  As shown in FIG. 11, the sedimentation basin 10 is a rectangular pond with a sludge pit 14 in plan view. Hereinafter, the long side direction of the sedimentation basin 10 may be referred to as the longitudinal direction, and the short side direction may be referred to as the width direction. The sedimentation basin 10 shown in FIGS. 11 and 12 receives sewage from a water conduit 10b provided on the right side of the figure (see FIG. 12), and the received water is directed to the left side of the figure, for example, 0.03 m / min. Slowly flows at a flow rate of about 0.5 m / min (see straight arrows shown in FIGS. 11 and 12). That is, the longitudinal direction of the settling basin is the direction of water flow, and in FIGS. 11 and 12, the right side of the figure is the upstream side and the left side is the downstream side. The water that has flowed to the downstream side of the settling basin 10 is discharged from an overflow weir (not shown) and sent to, for example, a reaction tank of a sewage treatment system. In addition, the bottom face 100a of the pond bottom 10a is slightly inclined so that the water depth of the settling basin 10 increases toward the upstream side.

  A sludge pit 14 for collecting sludge accumulated on the pond bottom 10a is provided on the downstream side of the water conduit 10b. A sludge pump (not shown) is provided outside the sludge pit 14, and a suction pipe (not shown) of the sludge pump is disposed in the sludge pit 14. The sludge collected in the sludge pit 14 is sucked from the suction pipe by driving the sludge pump, and is conveyed outside the sedimentation basin 10.

  The pond bottom 10a has a length in the longitudinal direction of about 7 m, and the pond bottom 10a is provided with a plurality of flow paths extending along the longitudinal direction. The flow path will be described with reference to FIG.

  13 is a cross-sectional view taken along line EE in FIG. In FIG. 13, the horizontal direction of the figure is the width direction of the sedimentation basin 10.

  As shown in FIG. 13, on the bottom surface 100a of the pond bottom 10a, a plurality of flow path forming members 13 are arranged at predetermined intervals in the width direction. These flow path forming members 13 have a pair of inclined pieces 13a connected substantially at right angles, and have an angle shape in which corners 13b are formed at the connecting portions of these inclined pieces 13a. The flow path forming member 13 has a posture in which the corner portion 13b faces upward, and the tip portions of the inclined pieces 13a are fixed to the bottom surface 100a. These flow path forming members 13 extend in the entire longitudinal direction of the pond bottom 10a as shown in FIGS. As shown in FIG. 13, an inclined portion 100 c that is inclined inward in the width direction is formed at the lower end portion of the pair of side walls 10 c in the sedimentation basin 10.

  In the sedimentation basin 10 of the present embodiment, five flow paths F are provided. Among these five flow paths F, two flow paths F provided on both sides in the width direction of the sedimentation basin 10 are defined by the inclined portion 100c of the side wall 10c, the bottom surface 100a, and the inclined piece 13a of the flow path forming member 13. The upper part is an open space. Further, the three flow paths F on the center side in the width direction are spaces that are defined by the inclined pieces 13a and the bottom surfaces 100a of the adjacent flow path forming members 13 and open upward. The sludge in the sewage that has flowed into the settling basin 10 settles toward the pond bottom 10 a and enters the flow path F, and flows down along the inclined portion 100 c of the side wall 10 c and the inclined piece 13 a of the flow path forming member 13. As a result, the settled sludge is deposited on the bottom surface 100a in the flow path F. In addition, the sludge which settled on the corner | angular part 13b of the flow-path formation member 13 flows down to the bottom face 100a via any inclination piece 13a. Here, the inclination angle of the inclined portion 100c of the side wall 10c and the inclined piece 13a of the flow path forming member 13 is not particularly limited, but in the sedimentation basin 10 of the present embodiment, both are set to 45 degrees. Yes. The flow path forming member 13 is made of metal such as stainless steel, but may be formed of concrete integrally with the bottom surface 100a. Further, the inclined piece 13a of the flow path forming member 13 and the inclined portion 100c of the side wall 10c may have an arcuate cross-sectional shape. The sludge accumulated on the bottom surface 100a in the flow path F is moved to the sludge pit 14 by the flow of water discharged from a discharge port described later.

  The sedimentation basin 10 shown in FIGS. 11 to 13 is provided with a transfer system 20. The transfer system 20 discharges the water supplied by the space forming member 28, the support member 29 that supports the space forming member 28, the mounting frame 26 on which the support member 29 is suspended, the water supply pipe 271, and the water supply pipe 271. And a discharge port 27 to be used.

  As shown in FIG. 13, the space forming member 28 is disposed at the center in the width direction in each flow path F and on the bottom surface 100 a while being separated from the bottom surface 100 a. As shown in FIGS. 11 and 12, the space forming member 28 extends along the longitudinal direction of the sedimentation basin 10, and the total length of the space forming member 28 is the length of the pond bottom 10a in the longitudinal direction. The same. The water supply pipe 271 corresponds to an example of a fluid supply pipe, and one end side is connected to a water supply source (not shown), and the other end side is connected to a downstream portion of the space forming member 28 as shown in FIG. ing.

  The mounting frame 26 has a U-shaped cross section, and is stretched over the pair of side walls 10c in a state of extending in the width direction as shown in FIGS. Further, as shown in FIGS. 11 and 12, a plurality of mounting frames 26 are provided at predetermined intervals in the longitudinal direction. As shown in FIG. 13, a plurality of support members 29 are provided in a state extending in the vertical direction at positions corresponding to the space forming members 28 in the width direction. Further, as shown in FIG. 12, a plurality of support members 29 are provided at predetermined positions in the longitudinal direction at positions corresponding to the positions of the attachment frames 26 in the longitudinal direction. As shown in FIG. 13, these support members 29 are attached to the pipe member 291 extending in the vertical direction, the lower screw member 292 attached to the lower end of the pipe member 291, and the upper end of the pipe member 291. And an upper screw member 293. These support members 29 support the space forming member 28 by attaching the lower screw member 292 to the space forming member 28 and attaching the upper screw member 293 to the attachment frame 26.

  FIG. 14A is an enlarged view showing a G portion in FIG. 13 in an enlarged manner. In FIG. 14A, the horizontal direction of the figure is the width direction of the sedimentation basin 10.

  The space forming member 28 shown in FIG. 14A has substantially the same cross-sectional shape as the space forming member 8 shown in FIG. 3, and the lower end of the space forming member 28 opens downward. Hereinafter, this opened portion is referred to as a suction port 281. The suction port 281 is an opening having a length L of 80 mm or more in the width direction, and is separated from the bottom surface 100a. The space forming member 28 divides the flow path F and forms a space S3 in which a portion above the lower end is closed. The upper end portion 282 of the space forming member 28 is closed, and the space S3 becomes narrower as the lower end portion connected to the suction port 281 approaches the suction port 281 by the arc-shaped side surface 280. A cylindrical portion 283 having a screw groove corresponding to the lower screw member 292 of the support member 29 on the inner periphery is provided on the upper end portion 282 of the space forming member 28. Here, the lower screw member 292 is threaded at the lower portion and the upper portion is not threaded. The upper portion is inserted into the pipe member 291 and welded or the like to the pipe member 291. It is fixed to. The space forming member 28 is supported by the support member 29 by screwing the lower screw member 292 into the cylindrical portion 283.

  FIG. 14B is an enlarged view showing an H portion of FIG. In FIG. 14B as well, the horizontal direction of the figure is the width direction of the sedimentation basin 10.

  As shown in FIG. 14B, the upper screw member 293 is threaded at the upper portion and the lower portion is not threaded. This lower portion is inserted into the pipe member 291. It is fixed to the pipe member 291 by welding or the like. The support member 29 is suspended from the mounting frame 26 by tightening the upper screw member 293 with nuts N from above and below the mounting frame 26 in a state where the upper screw member 293 is inserted into a hole formed in the mounting frame 26. . The support member 29 can adjust the position in the vertical direction by adjusting the position of the nut N in the upper screw member 293. Accordingly, the vertical position of the space forming member 28 supported by the support member 29 can be adjusted, and the separation distance between the suction port 281 and the bottom surface 100a can be changed. Even in a state where sewage is accumulated in the sedimentation basin 10, the support member 29 is removed from the mounting frame 26, and the removed support member 29 is lifted to lift the space forming member 28 and a discharge port 27 described later. be able to. Thereby, even in a state where sewage is accumulated in the sedimentation basin 10, maintenance of the space forming member 28 and the discharge port 27 can be performed.

  Further, as shown in FIG. 14A, the space S3 in the space forming member 28 is provided with a discharge port 27 for discharging a fluid into the space S3. The discharge port 27 has the same structure as the discharge port 7 shown in FIG. As described above with reference to FIG. 12, the water supply pipe 271 extending downward to the downstream side portion of the space forming member 28 penetrates the space forming member 28, and as shown in FIG. It is in S3. A portion 2711 of the water supply pipe 271 entering the space S3 is lower than the radial center of the space forming member 28, as in the portion 711 of the water supply pipe 71 entering the space S2 shown in FIG. And bent horizontally toward the upstream side (front side in the figure). In the present embodiment, the anti-winding plate 95 shown in FIG. 3 is not provided. The reason for this is that string-like contaminants are removed in the settling basin, and the sewage received by the settling basin 10 contains almost no string-like contaminants, so it is necessary to prevent such string-like contaminants from being wrapped. This is because there is little nature.

  The discharge port 27 of the present embodiment is provided at the end portion on the downstream side in the longitudinal direction in the space S <b> 3, below the center in the radial direction of the space forming member 28, and more than the suction port 281. Located above. Water is discharged from the discharge port 27 in parallel or substantially in parallel with the axial center of the space forming member 28 toward the upstream side. That is, water is discharged in the horizontal or substantially horizontal direction toward the upstream side. In FIGS. 11 and 12, the right side of the drawing is the downstream side in the discharge direction, and the left side of the drawing is the upstream side in the discharge direction.

  When water is discharged from the discharge port 27 into the space S3 of the space forming member 28, a pressure difference is generated between the space forming member 28 (space S3) and the outside, and is deposited on the bottom surface 100a in the flow path F. The sludge is sucked into the space S3 from the suction port 281 as indicated by the curved arrow shown in FIG. Further, in the space S3 of the space forming member 28, the sucked sludge moves toward the downstream side (sludge pit 14 side) in the discharge direction by the flow of water discharged from the discharge port 27. As shown in FIG. 14 (a), when the suction port 281 is a narrowed opening, it is difficult for sludge moving in the space S3 to go out of the space S3, and the rise of sludge is further suppressed. .

  Since the sludge has a particle size smaller than that of sand and is easier to move than sand, the sludge can be sufficiently moved at a discharge flow rate slower than the discharge flow rate of water at the discharge port 7 shown in FIG. . For this reason, the discharge flow rate in the discharge port 27 of this embodiment can be made into about 1/3 of the discharge flow rate of the water in the discharge port 7 shown in FIG. 3, for example. Moreover, the discharge amount of the water discharged from the discharge port 27 can also be made into about 1/3 of the discharge amount of the water discharged from the discharge port 7 shown in FIG. The water discharge rate can be about 500 liters per minute.

  According to the transfer system 20 of the present embodiment described above, it is possible to suppress the sludge whilst sufficiently moving the sludge.

  Then, the sludge removal method which removes the sludge accumulated in the pond bottom part 10a of the sedimentation basin 10 of this embodiment from the sedimentation basin 10 is demonstrated. This sludge removal method corresponds to an example of the contaminant removal method.

  FIG. 15 is a flowchart showing the flow of the sludge removal method.

  The sewage that has flowed into the sedimentation basin 10 passes through the sludge pit 14, reaches the upstream end of the flow path F, and further flows in the extending direction of the flow path F. While the sewage flows in the extending direction of the flow path F, the sludge contained in the sewage sinks into the sludge pit 14 and the pond bottom 10a. The sludge settled on the inclined portion 100c of the side wall and the flow path forming member 13 in the flow path F flows down toward the bottom face 100a. Thus, sludge accumulates on the bottom surface 100a in the flow path F.

  In the sludge removal method in the present embodiment, first, a sludge pump (not shown) provided in the sludge pit 14 is driven to remove the sludge in the sludge pit 14 from the sludge pit 14 (step S1). The sludge accumulated in the sludge pit 14 at this stage is mainly the sludge that has settled in the sludge pit 14 and accumulated in the sludge pit 14 out of the sludge in the sludge flowing into the sedimentation basin 10.

  Next, in a state where the sludge pump is driven, 500 liters of water per minute is discharged from the discharge port 27 under water for 3 minutes (step S2). In step S <b> 2, water is discharged from the flow path F into the space S <b> 3 partitioned by the space forming member 28. As water is discharged into the space S3 from the discharge port 27, a pressure difference is generated between the space forming member 28 (space S3) and the outside, and the sludge accumulated on the bottom surface 100a in the flow path F is sucked in. The air is sucked into the space S3 from the mouth 281 (see the curved arrow shown in FIG. 14A). Further, in the space S3 of the space forming member 28, the sucked sludge moves toward the downstream side (sludge pit 14 side) in the discharge direction by the flow of water discharged from the discharge port 27. The sludge that moves in the space S3 of the space forming member 28 is unlikely to go out of the space forming member 28 at the portion where the pressure difference is generated, and the sludge is prevented from rising. Thus, the sludge accumulated on the bottom surface 100a in the flow path F moves in the space S3 of the space forming member 28 and eventually reaches the sludge pit 14. The movement of the sludge here corresponds to an example of a movement process. This moving process does not need to be performed after draining the water in the sedimentation basin 10 and reducing or eliminating all the water in the sedimentation basin 10, and is performed in a state where sewage is continuously received in the sedimentation basin. The sludge that has reached the sludge pit 14 is transported to the outside of the sedimentation basin 10 by the sludge pump that has started driving in the previous step S 1, and the sludge is removed from the sedimentation basin 10. The removal of sludge here corresponds to an example of a discharge process.

  And when discharge of the water from the discharge outlet 27 is complete | finished and predetermined time passes after that, the sludge pump which started the drive in step S1 will be stopped (step S3). Further, when a predetermined time has passed or when sludge has accumulated to some extent in the sludge pit 14 due to the sludge that has settled, step S1 is performed again. As described above, Step S1 to Step S3 are repeatedly performed after the acceptance of sewage is started.

  According to the sludge removal method of the present embodiment, the sludge can be removed from the sedimentation basin 10 by sufficiently moving the sludge in the sedimentation basin 10 while suppressing the rising of the sludge.

  Next, the sedimentation basin provided with the second embodiment of the transfer system will be described. In the following description, components having the same names as the names of the components described so far will be described with the reference numerals used so far, and redundant descriptions may be omitted.

  FIG. 16 is a cross-sectional view showing a mode corresponding to FIG. 13 in a sedimentation basin provided with the transfer system of the second embodiment. In FIG. 16, the horizontal direction of the figure is the width direction of the sedimentation basin 10.

  The transfer system 20 provided in the sedimentation basin 10 shown in FIG. 16 includes a space forming member 28 that is a part of the trough 33, a discharge port 27 provided in the space forming member 28, and a water supply pipe 271. Yes. The trough 33 is on the downstream side of the sludge pit 14 shown in FIG. 11 and extends in the longitudinal direction of the pond bottom 10a, and a plurality of troughs 33 are provided at predetermined intervals in the width direction. The trough 33 includes a groove forming body 331 that forms a groove, a space forming member 28, and a discharge port 27. A water supply pipe 271 extending in the vertical direction from the outside of the sedimentation basin 10 toward the basin 10 a is connected to the discharge port 27. In addition, an inclined surface 16 that is inclined downward from the both sides in the width direction of the trough 33 toward the trough 33 and connected to the trough 33 is formed of concrete on the pond bottom portion 10a. The inclined surface 16 extends in the longitudinal direction of the pond bottom 10a. In FIG. 16, the portion of the pond bottom 10a formed by concrete is indicated by cross hatching.

  FIG. 17A is an enlarged view showing an I portion of FIG. In FIG. 17A, the horizontal direction is the width direction.

  As shown in FIG. 17A, the trough 33 has a first arc-shaped member 33a and a second arc-shaped member 33b each having a cross-sectional shape of 5/8 arc. The first arc-shaped member 33a and the second arc-shaped member 33b are formed by cutting out a part of a pipe material made of stainless steel or the like. The first arcuate member 33a is a portion between 9 o'clock and 1 o'clock and 2 o'clock (3/8), pointed by the short hand of the watch, in a pipe member having a thickness of about 3-4 mm and a diameter of about 250 mm. (Arc) is cut out. Further, the second arcuate member 33b is a pipe member having a thickness of about 3 to 4 mm and a diameter of about 150 mm, which is a portion between 3 o'clock and 5 o'clock to 9 o'clock (3 / 8 arcs). The trough 33 is formed by abutting and joining the end corresponding to the above 9 o'clock in the second arcuate member 33b with the end corresponding to the above 9 o'clock in the second arcuate member 33a. A space forming member 28 and a groove forming body 331 are formed by the first arc-shaped member 33a and the second arc-shaped member 33b. The space forming member 28 opens downward. The portion opening downward is the suction port 281 of the space forming member 28. The suction port 281 is an opening having a length L of 80 mm or more in the width direction, and is separated from the bottom 331 a of the groove forming body 331. The bottom 331a of the groove forming body 331 corresponds to an example of the bottom. An upper end portion 282 of the space forming member 28 is closed in an arc shape and is inclined downward. The space forming member 28 forms a space S3 in which a portion above the lower end is closed. The space S <b> 3 becomes narrower as a lower end portion connected to the suction port 281 approaches the suction port 281.

  Further, the groove forming body 331 is open upward. Hereinafter, the left half in the width direction of the groove forming body 331 shown in FIG. 17A is referred to as one end side of the groove forming body 331, and the right half in the width direction of the groove forming body 331 is the other of the groove forming body 331. It is called the end side. The space forming member 28 is connected to one end side of the groove forming body 331 through a common portion in a state of being separated from the other end side of the groove forming body 331. Thereby, the space between the other end side of the groove forming body 331 and the space forming member 28 opens upward. Hereinafter, the portion opening upward is referred to as the opening 334 of the trough 33. Of the spaces in the groove forming body 331, the space excluding the space S3 of the space forming member 28 is referred to as a space S4. That is, the space that includes the space S3 and the space S4 corresponds to the groove, and the opening 334 of the trough 33 corresponds to the opening of the groove. The space forming member 28 in the present embodiment is provided in the groove, and the suction port 281 is located below the opening of the groove.

  Thus, since the space forming member 28 is connected to one end side in a state of being separated from the other end side of the groove forming body 331, a member that supports the space forming member 28 can be omitted. As a result, the sludge sedimentation into the groove is not inhibited by the member that supports the space forming member 28 over the entire length of the trough 3.

  As described above, the trough 3 of the present embodiment is formed by joining the first arcuate member 33a having a diameter of approximately 250 mm and the second arcuate member 33b having a diameter of approximately 150 mm. Therefore, the gap W between the space forming member 28 and the other end of the groove forming body 331 is secured about 100 mm over the entire length of the trough 33. Furthermore, since the space forming member 28 and the groove forming body 331 have a common part that is partially shared, it is easy to secure the gap W, and as a result, the size of the trough 33 in the width direction is suppressed. Can do.

  The sludge contained in the sewage flowing into the sedimentation basin 10 settles on the pond bottom 10a in the course of the sewage flowing downstream, and the sludge settled on the inclined surface 16 further flows along the inclined surface 16. It flows down towards the trough 33. The sludge that has flowed down from the right inclined surface 16 in FIG. 17A enters the groove through the opening 3334 of the trough 33. In addition, the sludge that has flowed down from the left inclined surface 16 in FIG. 17A enters the groove through the opening 334 of the trough 33 through the arc-shaped side surface of the space forming member 28. As a result, the sludge settled on the pond bottom 10a is collected at the bottom of the groove.

  FIG. 17B is a JJ cross-sectional view in FIG. In FIG. 17B, the horizontal direction in the figure is the direction in which the trough 33 extends, the right side in the figure is the upstream side (sludge pit 14 side), and the left side is the downstream side.

  As shown in FIG. 17A and FIG. 17B, the water supply pipe 271 extending downward to the space forming member 28 has a lower end portion penetrating the upper end portion 282 of the space forming member 28, and the space forming member 28. It communicates with the space S3. In addition, in the space S3 of the space forming member 28, a discharge port 27 that discharges fluid into the space S3 is provided in a region where the water supply pipe 271 communicates. The discharge port 27 is formed by partitioning the upper portion of the space S <b> 3 in the space forming member 28 with a partition member 272. The partition member 272 includes a horizontal portion 2721 extending in a horizontal state in the extending direction of the trough 33, and an inclined portion 2722 inclined upward from the downstream end portion of the horizontal portion 2721. The horizontal portion 2721 is connected to both sides in the width direction across the upper end portion of the inner peripheral surface of the space forming member 28, and its upstream end (sludge pit 14 side) is upstream of the lower end portion of the water supply pipe 271. Located on the side. In addition, the inclined portion 2722 has a downstream end connected to the downstream side of the inner peripheral surface of the space forming member 28 with respect to the lower end portion of the water supply pipe 271, and the downstream side of the discharge port 27 is connected to the inclined portion 2722. Blocked. By these, the area | region where the water supply pipe | tube 271 connects in space S3 of the space formation member 28 is partitioned off by the partition member 272. The discharge port 27 of the present embodiment may have the same structure as the discharge port 27 shown in FIG.

  From the discharge port 27, the water supplied from the water supply pipe 271 is discharged in the horizontal direction or the substantially horizontal direction toward the upstream side (see the right-pointing arrow in FIG. 17B). That is, in FIG. 17B, the right side of the figure is the downstream side in the discharge direction, and the left side of the figure is the upstream side in the discharge direction. As water is discharged from the discharge port 27 into the space S3 of the space forming member 28, a pressure difference is generated between the space forming member 28 (space S3) and the outside (space S4), and is accumulated at the bottom of the groove. The sludge is sucked into the space S3 from the suction port 281 as indicated by the curved arrow shown in FIG. Further, in the space S3 of the space forming member 28, the sucked sludge moves toward the downstream side (sludge pit 14 side) in the discharge direction by the flow of water discharged from the discharge port 27. As shown in FIG. 17 (a), the suction port 281 is an opening that is narrowed in the width direction, so that it is difficult for sand moving in the space S2 to go out of the space S3, and the sludge rises. Is suppressed more.

That is, the sedimentation basin provided with the transfer system of the second embodiment is a sedimentation basin in which sludge contained in the received water settles in a groove provided at the bottom of the pond,
A space forming member in which an upper end portion forms a closed space, and a suction port spaced from the bottom of the groove is provided below the upper end portion;
A discharge port for discharging fluid into the space;
The suction port functions as an opening for sucking the sludge accumulated in the groove into the space by discharging fluid from the discharge port,
The space forming member functions as a path through which the sludge sucked into the space moves toward the downstream side in the discharge direction of the fluid by discharging the fluid from the discharge port.
The pond bottom has a groove forming body for forming the groove,
The space forming member is connected to the one end side in a state of being separated from the other end side among the one end side and the other end side in the width direction orthogonal to the extending direction of the groove of the groove forming body, It is provided along the extending direction of the groove.

The space forming member is provided in the groove,
The suction port may be located below the opening of the groove.

  Furthermore, the space forming member may have a part shared with a part of the groove forming body.

  Further, the space forming member may have a curved surface at the upper end portion.

Further, the pond bottom has a pair of inclined surfaces inclined downward toward the groove on both sides in the width direction of the groove,
One of the pair of inclined surfaces is a lower end portion connected to the other end side of the groove forming body,
The other of the pair of inclined surfaces may have a lower end portion connected to the upper end portion of the space forming member.

  The space forming member may be connected to the one end side over substantially the entire length of the groove.

  Next, a sedimentation basin provided with a third embodiment of the transfer system will be described.

  FIG. 18 is a plan view of a sedimentation basin provided with a third embodiment of the transfer system as viewed from above. In FIG. 18, the horizontal direction of the figure is the longitudinal direction of the sedimentation basin 10, and the vertical direction of the figure is the width direction of the sedimentation basin 10. FIG. 19 is a cross-sectional view taken along the line KK of the settling basin shown in FIG. 18. In FIG. 20 is an LL cross-sectional view of the sedimentation basin shown in FIG. 18. In FIG. 20, the horizontal direction of the diagram is the width direction of the sedimentation basin 10.

  In the sedimentation basin 10 shown in FIGS. 18 to 20, the longitudinal direction is the direction of water flow. In FIGS. 18 and 19, the right side of the figure is the upstream side and the left side is the downstream side. The sedimentation basin 10 includes a pair of side walls 10c (see FIG. 18) extending in the longitudinal direction, an upstream wall 10h extending in the width direction and positioned on the upstream side, and extending in the width direction and positioned on the downstream side. It is a pond having a rectangular shape in plan view, having a downstream wall 10g, having a length in the longitudinal direction of about 35 m and a length in the width direction of about 25 m. As shown in FIG. 19, an overflow weir 100g is provided on the downstream wall 10g. The sewage that has passed over the weir 100 g is sent to, for example, a reaction tank of a sewage treatment system. Further, as shown in FIG. 18, the upstream wall 10h is provided with an opening 100h communicating with a water conduit (not shown). Note that each of the pair of side walls 10c and the upstream wall 10h is provided with a plurality of pillars at predetermined intervals in the extending direction thereof.

  As shown in FIGS. 18 and 20, a sludge pit 14 is provided in the center portion in the width direction on the upstream side of the settling basin 10. A sludge pump (not shown) is provided outside the sludge pit 14, and a suction pipe (not shown) of the sludge pump is disposed in the sludge pit 14. As shown in FIGS. 18 and 20, a pair of accumulation grooves 141 extending in the width direction and connected to the sludge pit 14 are provided on both sides in the width direction of the sludge pit 14. Each of these accumulation grooves 141 is a groove having a width of about 4 m in the longitudinal direction of the settling basin 10 and having a length of about 10 m in the width direction of the settling basin 10. . These accumulation grooves 141 correspond to an example of a transfer path, and the groove bottom surface 141a of the accumulation groove 141 corresponds to an example of a groove bottom part of the transfer path. As shown in FIG. 20, the groove bottom surface 141 a of each accumulation groove 141 is inclined so that the water depth of the settling basin 10 increases toward the sludge pit 14.

  As shown in FIG. 18, the upstream side of the sludge pit 14 and the accumulation groove 141 in the sedimentation basin 10 is partitioned into four regions by three partition walls 10 d extending in the longitudinal direction. A pond bottom 10a is provided. In addition, similarly to the side wall 10c, the partition wall 10d is also provided with pillar portions at predetermined intervals in the longitudinal direction, and the lower end portion of the partition wall 10d where the pillar portions are not provided is in a haunch shape. The cross-sectional shape is large. Further, a beam 10e (see FIG. 19) extending in the width direction is provided between the pillar portions in the adjacent partition wall 10d. Furthermore, a beam extending in the width direction is also provided between the pillar portion of the side wall 10c and the pillar portion of the partition wall 10d. In FIG. 18 and FIG. 20, the beam is omitted for the sake of simplicity. Further, as shown in FIGS. 19 and 20, a ceiling 10 f is provided on the upstream portion of the pond bottom 10 a and above the sludge pit 14 and the accumulation groove 14. In FIG. 18, the ceiling 10 f is omitted to show the accumulation groove 14.

  The flow path forming member 13 having the same cross-sectional shape as the flow path forming member 13 shown in FIGS. 11 to 13 is substantially in the longitudinal direction of the bottom surface 100a of the pond bottom 10a. It is arranged in a state extending over the entire length. The inclined part 100c shown in FIG. 13 is not provided in the lower end part of the side wall 10c of this embodiment, and the inclined part is not provided also in the lower end part of the partition wall 10d. In this embodiment, the 2nd flow-path formation member 131 which consists of one inclination piece is arrange | positioned at the both ends side part of the width direction in the bottom face 100a of the pond bottom part 10a. In the present embodiment, as shown in FIG. 20, each of the four regions partitioned by the partition wall 10 d in the pond bottom portion 10 a has 4 by each of the flow channel forming member 13 and the second flow channel forming member 131. Two flow paths F are formed in a state of being aligned in the width direction. In addition, an inclined part may be provided in the lower end part of the side wall 10c or the partition wall 10d, and the 2nd flow path formation member 131 may be abbreviate | omitted.

  A transfer system 20 is provided in each of the regions partitioned by the partition wall 10d in the sedimentation basin 10. The transfer system 20 includes a space forming member 28, a support member 29, a mounting frame 26, a water supply pipe 271, and a discharge port 27, similarly to the transfer system 20 shown in FIGS. 11 to 14. The space forming member 28 has the same cross-sectional shape as the space forming member 28 shown in FIG. 14, and is disposed in each of the flow paths F so as to extend over substantially the entire length in the longitudinal direction of the flow path F. These space forming members 28 are supported by the support member 29 and the mounting frame 26 in the same configuration as the support member 29 and the mounting frame 26 shown in FIGS. 11 to 13 while being separated from the bottom surface 100a of the pond bottom 10a. Yes. The attachment frame 26 extends in the width direction of the sedimentation basin 10 in each region partitioned by the partition wall 10d in the sedimentation basin 10, and the attachment frame 26 is spaced apart in the longitudinal direction of the sedimentation basin 10. A plurality of them are arranged. Both ends of the mounting frame 26 are supported by receiving frames 261. These receiving frames 261 are fixed to portions above the water surface in each of the side wall 10c and the partition wall 10d. Support members 29 are suspended from the attachment frames 26 supported by the receiving frames 261, respectively.

  As shown in FIG. 19, a plurality of water supply pipes 271 of the present embodiment are connected to the upper end portion of the space forming member 28 with an interval of about 6 m in the longitudinal direction. These water supply pipes 271 are bent to the upstream side (the sludge pit 14 and the accumulation groove 141 side) after passing through the space forming member 28 and entering the space forming member 28 in the same manner as the water supply pipe 271 shown in FIG. The same discharge port as the discharge port 27 shown in FIG. 14 is formed. Thus, in the present embodiment, five discharge ports are provided in the space forming members 28 with an interval of about 6 m in the longitudinal direction. From these discharge ports, the water supplied from the water supply pipe 271 is discharged in the horizontal direction or the substantially horizontal direction toward the upstream side (the right side in FIGS. 18 and 19). That is, in FIGS. 18 and 19, the right side of the figure is the downstream side in the discharge direction, and the left side of the figure is the upstream side in the discharge direction. Hereinafter, among the five discharge ports formed in each space forming member 28, the discharge port on the most downstream side in the discharge direction (the most upstream side in the sedimentation basin 10) may be referred to as a first discharge port. The first discharge port, the third discharge port, the fourth discharge port, and the fifth discharge port may be referred to in order from the first discharge port toward the upstream side in the discharge direction (downstream side in the sedimentation basin 10). is there. As seen from the sedimentation basin 10 shown in FIGS. 18 and 19, the first discharge port is provided at the most upstream side of the water flow in the sedimentation basin 10, and the fifth discharge port is the water in the sedimentation basin 10. It is provided at the most downstream side of the flow. 18 and 20, the water supply pipe 271 is omitted to simplify the drawing.

  As shown in FIGS. 18 and 19, the channel forming member 13 and the second channel forming member 131 ′ extending in the width direction of the sedimentation basin 10 are settled on the groove bottom surfaces 141 a of the pair of accumulation grooves 141. A plurality of channels F ′ are formed which are arranged at intervals in the longitudinal direction of the pond 10 and extend over substantially the entire length of the accumulation groove 141. In the present embodiment, three flow paths F ′ are formed in each of the pair of accumulation grooves 141 sandwiching the sludge pit 14. A second transfer system 20 ′ is provided in each of the pair of accumulation grooves 141. Similar to the transfer system 20, the second transfer system 20 ′ includes a space forming member 28, a support member 29, a mounting frame 26, a water supply pipe 271, and a discharge port. The space forming member 28 has the same cross-sectional shape as the space forming member 28 shown in FIG. 14, and is disposed in each of the flow paths F ′ so as to extend over substantially the entire length of the flow path F ′. These space forming members 28 are separated from the groove bottom surface 141 a of the accumulation groove 141 by the support member 29 having the same configuration as the support member 29 of the transfer system 20 and the mounting frame 26 having the same cross-sectional shape as the mounting frame 26 of the transfer system 20. Supported by the state. As shown in FIG. 18, the mounting frame 26 is disposed at a predetermined interval in the width direction of the sedimentation basin 10 in a state of extending in the longitudinal direction of the sedimentation basin 10 above the accumulation groove 141. In the present embodiment, three attachment frames 26 are arranged in each of the accumulation grooves 141. As shown in FIGS. 18 and 20, the mounting frame 26 arranged at the center in the width direction of the settling basin 10 among the three mounting frames 26 is a receiver whose upstream end portion is fixed to the upstream wall 10 h. The downstream end portion is supported by the frame 261 and is supported by the receiving frame 261 fixed to the upstream surface of the partition wall 10d. Further, as shown in FIGS. 18 and 19, of the three attachment frames 26, the two attachment frames 26 arranged on the outer side in the width direction of the sedimentation basin 10 each have an upstream end portion of the sedimentation basin 10. Is supported by a receiving frame 261 fixed to the upstream wall 10h, and an end portion on the downstream side is supported on a mounting frame 26 arranged on the most upstream side in the transfer system 20. A support member 29 is suspended from each of the mounting frames 26.

  As shown in FIG. 20, each of the space forming members 28 of the second transfer system 20 ′ has a water supply pipe 271 having an outer end portion in the width direction of the settling basin 10 and an intermediate portion in the width direction of the settling basin 10. It is connected to the. These water supply pipes 271 are bent to the center in the width direction (sludge pit 14 side) after passing through the space forming member 28 and entering the space forming member 28, as in the case of the water supply pipe 271 shown in FIG. The same discharge port as the discharge port 27 shown is formed. Thereby, in this embodiment, in each space formation member 28, two discharge ports are provided at intervals of about 5 m in the longitudinal direction. From these discharge ports, water supplied from the water supply pipe 271 is discharged horizontally or substantially horizontally toward the sludge pit 14 side. That is, in each of the pair of accumulation grooves 141, the outer side in the width direction of the settling basin 10 is the upstream side in the discharge direction, and the inner side in the width direction (the sludge pit 14 side) of the settling basin 10 is the downstream side in the discharge direction. Hereinafter, of the two discharge ports formed in each of the space forming members 28 of the second transfer system 20 ′, the discharge port on the upstream side in the discharge direction (outside in the width direction of the settling basin 10) may be referred to as an outer discharge port. In some cases, the inner discharge port in the width direction of the settling basin 10 is referred to as an inner discharge port. In FIGS. 18 and 19, the water supply pipe 271 of the transfer system 20 ′ is omitted in order to simplify the drawings.

  Then, the 2nd sludge removal method which removes the sludge accumulated in the sedimentation basin 10 in which 3rd Embodiment of the transfer system was provided from the sedimentation basin 10 is demonstrated. This second sludge removal method corresponds to an example of the contaminant removal method.

  FIG. 21 is a flowchart showing the flow of the second sludge removal method.

  The sewage flowing into the sedimentation basin 10 passes through the sludge pit 14 and the accumulation groove 141, reaches the upstream end of the pond bottom 10a, and further flows along the extending direction of the pond bottom 10a. While the sewage flows, the sludge contained in the sewage sinks into the sludge pit 14, the accumulation groove 141, and the pond bottom 10a. The sludge settled in the accumulation groove 141 flows down to the groove bottom surface 141a in the flow path F 'through the flow path forming member 13 and the second flow path forming member 131'. In addition, it flows down to the groove bottom surface 141 a in the flow path F ′ through the outer peripheral surface of the space forming member 28. Thus, sludge accumulates on the groove bottom surface 141a in the flow path F '. The sludge that has settled on the pond bottom 10 a flows down to the bottom surface 100 a in the flow path F through the flow path forming member 13 and the second flow path forming member 131. In addition, the outer peripheral surface of the space forming member 28 is connected to the bottom surface 100 a in the flow path F. Thus, sludge accumulates on the bottom surface 100a in the flow path F.

  In the second sludge removal method in the present embodiment, first, a sludge pump (not shown) provided outside the sludge pit 14 is driven to remove the sludge in the sludge pit 14 from the sludge pit 14 (step S1). . The sludge accumulated in the sludge pit 14 at this stage is mainly the sludge that has settled in the sludge pit 14 and accumulated in the sludge pit 14 out of the sludge in the sludge flowing into the sedimentation basin 10. The sludge pump continues to be driven until it stops in step S23 described later.

  Next, 500 liters of water per minute is discharged for 3 minutes under water from only the inner discharge port of the two discharge ports in each accumulation groove 141 (step S2). In step S <b> 2, water is discharged from the flow path F ′ into the space partitioned by the space forming member 28. By discharging water from the inner discharge port, a pressure difference is generated between the inside and the outside of the space forming member 28, and the sludge accumulated on the groove bottom surface 141a of the inner portion in the width direction in the flow path F ′ is sucked. The air is sucked into the space partitioned by the space forming member 28 from the mouth. Further, in the space partitioned by the space forming member 28, the sucked sludge moves downstream in the discharge direction (toward the sludge pit 14) by the flow of water discharged from the inner discharge port. The sludge that moves in the space partitioned by the space forming member 28 is unlikely to go out of the space forming member 28 at the portion where the pressure difference is generated, and the sludge is prevented from rising. Thus, the sludge accumulated on the groove bottom surface 141a of the inner portion in the width direction in the flow path F ′ moves through the space partitioned by the space forming member 28 and eventually reaches the sludge pit 14. The sludge that has reached the sludge pit 14 is conveyed to the outside of the sedimentation basin 10 by a sludge pump, and the sludge is removed from the sedimentation basin 10. The removal of sludge here corresponds to an example of a discharge process.

  Next, the water discharge from the inner discharge port is stopped, and this time, 500 liters of water per minute is discharged from the outer discharge port for 3 minutes under water (step S3). In step S3, similarly to step S2, by discharging water into the space partitioned by the space forming member 28, a pressure difference is generated between the inside and outside of the space forming member 28, and this time, the width in the flow path F ′ is changed. The sludge accumulated on the groove bottom surface 141a of the outer portion in the direction is sucked into the space partitioned by the space forming member 28 from the suction port. Further, the sucked sludge moves in the space partitioned by the space forming member 28 downstream of the discharge direction (toward the inner discharge port) by the flow of water discharged from the outer discharge port, and reaches the inner discharge port. To do. As the momentum of water from the outer discharge port decreases around the inner discharge port, the sludge that reaches the periphery of the inner discharge port drops from the suction port of the space forming member 28 toward the groove bottom surface 141a. That is, sludge accumulates on the groove bottom surface 141a around the inner discharge port in the flow path F '.

  Next, the discharge of water from the outer discharge port is stopped, and 500 liters of water per minute is discharged from the inner discharge port for 3 minutes under water as in step S2 (step S4). By this step S4, the sludge accumulated on the groove bottom surface 141a around the inner discharge port in the flow path F ′ is sucked again into the space partitioned by the space forming member 28, and the sucked sludge is discharged downstream in the discharge direction. (Toward the sludge pit 14), the space partitioned by the space forming member 28 is moved, and eventually reaches the sludge pit 14. Steps S2 to S4 correspond to an example of the moving process. The sludge that has reached the sludge pit 14 is removed from the sedimentation basin 10 by a sludge pump. That is, the removal of sludge by the sludge pump, which corresponds to an example of the discharge process, is also performed here. The sludge discharged at this stage is mainly the sludge settled in the accumulation groove 141 and accumulated on the groove bottom surface 141a of the accumulation groove 141 among the sludge in the sewage flowing into the sedimentation basin 10.

  Next, out of the five discharge ports in each of the space forming members 28 provided in the pond bottom 10a, only 500 liters per minute from only the first discharge port on the most downstream side in the discharge direction (the most upstream side in the settling basin 10). Water is discharged under water for 3 minutes (step S4). In this step S4, water is discharged from the flow path F into the space partitioned by the space forming member 28. By discharging water from the first discharge port, a pressure difference is generated between the inside and the outside of the space forming member 28, and the sludge accumulated on the bottom surface 100a of the most upstream side portion in the flow path F is discharged from the suction port. It is sucked into the space partitioned by the space forming member 28. Further, in the space partitioned by the space forming member 28, the sucked sludge is moved downstream in the discharge direction (toward the sludge pit 14 and the accumulation groove 141) by the flow of water discharged from the first discharge port. Eventually, it reaches the sludge pit 14 and the accumulation groove 141. The sludge that has reached the sludge pit 14 is conveyed to the outside of the sedimentation basin 10 by a sludge pump, and the sludge is removed from the sedimentation basin 10. Here, sludge removal using a sludge pump, which corresponds to an example of a discharge process, is also performed.

  Next, the discharge of water from the first discharge port is stopped, and this time, 500 liters of water per minute is submerged in water for 3 minutes only from the second discharge port located upstream of the first discharge port in the discharge direction. Discharge (step S6). In step S6, similarly to step S5, by discharging water into the space partitioned by the space forming member 28, a pressure difference is generated between the inside and outside of the space forming member 28. The sludge accumulated on the groove bottom surface 141a around the discharge port is sucked into the space partitioned by the space forming member 28 from the suction port. Further, the sucked sludge moves in the space partitioned by the space forming member 28 toward the downstream side in the discharge direction (toward the first discharge port) by the flow of water discharged from the second discharge port. Reach the exit. In the vicinity of the first discharge port, the momentum of water from the second discharge port is reduced, so that the sludge that reaches the periphery of the first discharge port drops from the suction port of the space forming member 28 toward the bottom surface 100a. That is, sludge accumulates on the bottom surface 100a around the first discharge port in the flow path F.

  Next, the discharge of water from the second discharge port is stopped, and 500 liters of water per minute is discharged from the first discharge port for 3 minutes under water as in step S5 (step S7). By this step S7, the sludge accumulated on the bottom surface 100a around the first discharge port in the flow path F is sucked into the space partitioned by the space forming member 28, and the sucked sludge is downstream in the discharge direction ( It moves in the space partitioned by the space forming member 28 (toward the sludge pit 14 and the accumulation groove 141) and eventually reaches the sludge pit 14 and the accumulation groove 141. The sludge that has reached the sludge pit 14 is removed from the sedimentation basin 10 by a sludge pump. That is, the removal of sludge by the sludge pump, which corresponds to an example of the discharge process, is also performed here.

  Next, after stopping the discharge of water from the first discharge port, the discharge from the third discharge port (step S8) and the discharge from the second discharge port (step S9) by the same process as step S6 and step S7. And each process of discharge from a 1st discharge port (step S10) is implemented. By performing Steps S8 to S10, the sludge accumulated on the bottom surface 100a around the third discharge port reaches the sludge pit 14 and the accumulation groove 141, and the sludge that has reached the sludge pit 14 is sludge pumped. It is removed from the sedimentation basin 10. That is, the removal of sludge by the sludge pump, which corresponds to an example of the discharge process, is also performed here.

  Next, after stopping the discharge of water from the first discharge port, the discharge from the fourth discharge port (Step S11) and the discharge from the third discharge port (Step S12) by the same process as Step S8 to Step S10. ), Discharge from the second discharge port (step S13), and discharge from the first discharge port (step S14). By performing Steps S11 to S14, the sludge accumulated on the bottom surface 100a around the fourth discharge port reaches the sludge pit 14 and the accumulation groove 141, and the sludge that has reached the sludge pit 14 is precipitated by the sludge pump. Removed from the pond 10. That is, the removal of sludge by the sludge pump, which corresponds to an example of the discharge process, is also performed here.

  Next, after stopping the discharge of water from the first discharge port, the discharge from the fifth discharge port (step S15) and the discharge from the fourth discharge port (step S16) by the same process as step S11 to step S14. The respective steps of discharging from the third discharge port (step S17), discharging from the second discharge port (step S18), and discharging from the first discharge port (step S19) are performed. By performing Steps S15 to S19, the sludge accumulated on the bottom surface 100a around the fifth discharge port reaches the sludge pit 14 and the accumulation groove 141, and the sludge that has reached the sludge pit 14 is precipitated by the sludge pump. Removed from the pond 10. That is, the removal of sludge by the sludge pump, which corresponds to an example of the discharge process, is also performed here.

  By performing step S5 to step S19, the sludge settled on the pond bottom 10a is moved to the sludge pit 14 and the accumulation groove 141, and the sludge that has reached the sludge pit 14 is removed from the sedimentation basin 10 by the sludge pump. The These steps S5 to S19 correspond to an example of a moving process.

  Next, after stopping the discharge of water from the first discharge port, the discharge from the inner discharge port (Step S20), the discharge from the outer discharge port (Step S21), and the inner side, as in Steps S2 to S4 Discharge from the discharge port (step S22) is performed. By performing Steps S20 to S22, the sludge that has settled on the pond bottom 10a and moved to the accumulation groove 141 by Steps S5 to S19 reaches the sludge pit 14. The movement of the sludge here corresponds to an example of the movement process. Further, the sludge that has reached the sludge pit 14 is removed from the sedimentation basin 10 by a sludge pump. That is, sand removal by a sludge pump, which corresponds to an example of the discharge process, is also performed here.

  And when discharge of the water from an inner side discharge port is complete | finished and predetermined time passes after that, the sludge pump which started the drive by step S1 will be stopped (step S23). Further, when a predetermined time has passed or when sludge has accumulated to some extent in the sludge pit 14 due to the sludge that has settled, step S1 is performed again. As described above, Steps S1 to S23 are repeatedly performed after the acceptance of sewage is started.

  According to the second sludge removal method, the sludge can be removed from the sedimentation basin 10 by sufficiently moving the sludge while preventing the sludge from rising.

  Then, the modification of the transfer system demonstrated so far is demonstrated.

  FIG. 22 is a diagram illustrating a modified example of how to support the space forming member. In FIG. 22, the horizontal direction is the width direction as in FIG. 14.

  The space forming member 28 shown in FIG. 14 is supported by attaching the support member 29 to the cylindrical portion 283 of the upper end portion 282, but the space forming member 28 shown in FIG. 22 is on both sides of the suction port 281. A lower end 284 and an upper end portion 282 are supported by the support 39. The support 39 is formed by bending a plate material made of stainless steel or the like. For example, the support 39 has a length of about several tens of mm in the longitudinal direction, and has a predetermined interval along the extending direction of the space forming member 28. A plurality are provided with a gap. The support 39 includes a U-shaped frame portion 391, a pair of lower end support portions 392 extending in the vertical direction, and a frame portion 391 and a lower end support portion 392 extending in parallel to the bottom surface 100a. And a pair of connected portions 393. The frame portion 391 contacts the upper end portion 282 of the space forming member 28 with the open portion facing downward, and supports the upper end portion 282. The lower end support portion 392 supports each of the lower ends 284 of the space forming member 28. The pair of connection portions 393 are fixed on the base member 40 disposed on the bottom surface 100a. The space forming member 28 is supported by the support 39 in a state where the suction port 281 is separated from the bottom surface 100a.

  FIG. 23 is a view showing a modification in which the space forming member 28 shown in FIG. 13 is installed so as to be movable in the width direction. In FIG. 23, the horizontal direction is the width direction as in FIG.

  The space forming member shown in FIG. 13 is supported in a state in which the position in the width direction is fixed by attaching the upper screw member 293 of the support member 29 to the attachment frame 26. A rail member 37 extending in the width direction is provided instead of the frame 26, and a roller member 294 that engages with the rail member 37 movably in the width direction is provided instead of the upper screw member 293 of the support member 29. Yes. Moreover, in this modification, the flow path forming member 13 is omitted and the flow path F is not formed, and the pond bottom portion 10a is a flat surface including the bottom surface 100a. The roller member 294 can be moved in the width direction along the rail member 37 by a driving means (not shown), thereby forming a space supported by the support member 29 as shown by the arrow in the width direction in the figure. The member 28 can be moved in the width direction. By doing so, each time the space forming member 28 is slid in the width direction, water is discharged from the discharge port 27 and the sludge can be transferred to the sludge pit 14 side (see FIG. 11) over a wide width direction region. become able to.

  The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope described in the claims. For example, in the above-described embodiment, the transfer system 20 is provided in the settling basin 10, but the transfer system 20 is provided in a reservoir such as a dam lake and the sediment settled on the bottom of the dam lake is moved in one direction to be predetermined. It may be collected at the place. In addition, you may remove the earth and sand collected in the predetermined place from a dam lake etc. by attracting | sucking with a well-known sand pipe. Moreover, when providing the transfer system 20 in reservoirs, such as a dam lake, the form which moves a space formation member like the modification shown in FIG. 23 is preferable. Furthermore, the transfer system 20 may be provided in a factory or the like, and metal powder generated in the factory or the like may be moved in one direction and collected in a predetermined place.

  In addition, even if it is a structural requirement contained only in each description of embodiment and the modification demonstrated above, you may apply the structural requirement to another embodiment and a modification.

DESCRIPTION OF SYMBOLS 1 Sand settling basin 1a Pond bottom 3 Trough 3a Opening 4 Sand collection pit 6 Inclined surface 7 Discharge port 8 Space formation member 81 Suction port 82 Upper end part S1, S2 Space 10 Settling basin 10a Pond bottom 14 Sludge pit 141 Accumulation groove 20 Transfer system 28 Space forming member 27 Discharge port 29 Support member 33 Trough F Flow path S3, S4 Space

Claims (1)

A transfer system in which contaminants contained in the received liquid settle to the bottom,
A groove formed in the bottom and opening upward;
A space forming member that extends along the groove and that has a closed upper end portion and is provided with a suction port spaced from the bottom portion below the upper end portion;
A discharge port for discharging fluid into the space;
The suction port functions as an opening that opens in the groove and sucks the contaminants accumulated in the groove into the space by discharging fluid from the discharge port.
The space forming member functions as a path through which contaminants sucked into the space move toward the downstream side in the discharge direction of the fluid when the fluid is discharged from the discharge port.
The transfer system according to claim 1, wherein an upper portion of the groove connected to the opening of the groove is narrowed toward the opening of the groove.