JP6548180B2 - Scum removal method - Google Patents

Description

  The present invention relates to a scum removing method for removing scum using a scum removing device for flowing scum mixed water mixed with scum floating on the water surface of a settling basin to the outside of the settling basin.

  In the sedimentation basin provided in the sewage treatment facility, scum may float on the water surface. Since the scum floating on the water surface interferes with the purification process, a scum removing device for removing the scum may be provided in the sedimentation basin. As this scum removing device, the upper end portion floats on the surface of the water, the mechanism for sinking the upper end portion of the ridge at a predetermined timing, and the scum mixed water exceeding the submerged end portion is directed to the outside of the sedimentation basin. There is one having a trough that forms a flow path. As such a scum removing device, for example, those described in Patent Document 1 and Patent Document 2 are known. The scum mixed water flowing in the flow path and flowing out of the sedimentation basin is pumped up by a pump and a predetermined treatment for removing the scum is performed.

JP-A-7-305325 JP-A-9-131589

  In the scum removing apparatus described in Patent Document 1 and Patent Document 2, the flow rate of scum mixed water flowing into the flow path is determined by the distance from the water surface to the upper end when the upper end of the weir is submerged. is there. However, in the scum removing device described in Patent Document 1 and Patent Document 2, the crucible whose upper end portion floats on the water surface is lowered into water by a mechanism at a predetermined timing, and the upper end portion of the crucible is submerged. For this reason, there is a problem that the distance from the upper end portion of the weir in which the upper end portion is submerged to the water surface is changed due to the operation accuracy of the mechanism and the deterioration due to wear. In particular, the scum removing device described in Patent Document 2 is provided with a mechanism for submerging the upper end portion of the weir in water. For this reason, the dirt in the water may disturb the operation of the mechanism, and the submersion operation of the weir may become unstable. Furthermore, in the scum removing device described in Patent Document 1 and Patent Document 2, the relationship between the flow rate of scum mixed water flowing into the flow path and the pumping up flow rate of the pump that pumps up the scum mixed water is not taken into consideration. For this reason, there is a possibility that scum mixed water exceeding the pumping up flow rate of the pump flows into the flow path, and the scum mixed water overflows from the flow path and the scum can not be removed from the sedimentation basin. Moreover, the scum mixed water which flowed in into the flow path may be discharged out of the scum removing device by natural flow without using a pump. Also in this case, if scum mixed water exceeding the flow rate discharged to the outside of the scum removing device by natural flow flows into the flow path, the scum mixed water may overflow from the flow path and the scum may not be removed from the sedimentation tank. There is.

  An object of this invention is to provide the scum removal method which can make the scum mixing water which flows in into the flow path formed of the trough into appropriate flow rate in view of the said situation.

The scum removing method of the present invention which solves the above object is
A trough extending toward the outside of the sedimentation tank to form a flow path into which the scum mixed water flows, an inlet through which the scum mixed water provided in the trough passes when flowing into the flow path, and the flow A scum removing method for removing scum using a scum removing device comprising a lid for opening and closing an inlet, and a discharging means provided outside the settling tank and discharging scum mixed water flowing through the flow path In
Opening the lid;
Closing the lid body ;
Even if the water level of the sedimentation tank changes, the upper end portion of the weir connected to the trough is maintained at a position submerged in the water a predetermined distance from the water surface of the sedimentation tank, and the scum upstream of the upper end portion of the weir And d) mixing the mixed water with the upper end portion of the weir above the upper end portion of the weir .
The opening step and the closing step are performed such that the amount of inflow of scum mixed water flowing into the flow path by the opening of the lid does not exceed the amount of discharge of the discharging means .
The scum mixed water entrained on the downstream side of the upper end portion of the weir flows into the flow path from the inflow port by performing the open step .

  The opening step may be a step of opening the lid to a range where the inflow does not exceed the discharge.

  According to the scum removing method of the present invention, the scum mixed water flowing into the flow path formed by the trough can be made to have an appropriate flow rate.

It is a top view which shows an example of the sedimentation basin 1 in which the scum removal apparatus 10 used for the scum removal method of this invention was installed. It is AA sectional drawing of FIG. It is the B section enlarged view which expanded and showed the B section of FIG. It is a schematic perspective view of the weir, the trough, the connection member, and the lid shown in FIG. It is the side view which looked at a trough and a lid from the left side in FIG. It is a sectional view showing a scum pit. It is sectional drawing which shows the scum pit in the scum removal apparatus of other embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1: is a top view which shows an example of the sedimentation basin 1 in which the scum removal apparatus 10 used for the scum removal method of this invention was installed. Moreover, FIG. 2 is AA sectional drawing of FIG. In addition, in FIG. 1, the sludge scraping machine 30 shown in FIG. 2 is abbreviate | omitted. Moreover, in FIG. 1 and FIG. 2, the opening / closing mechanism 15 shown in FIG. 3 is abbreviate | omitted.

  As shown in FIG. 1, the sedimentation basin 1 is a pond having a substantially rectangular shape in a plan view surrounded by a pair of side walls 1a, an upstream wall 1b, and a downstream wall 1c. The settling basin 1 is for removing sludge and scum contained in the water flowing into the settling basin 1 from the left side in FIG. The water from which the sludge and scum have been removed flows through the drainage weir 40 disposed on the right in FIG. Hereinafter, the left direction in FIG. 1 may be referred to as an upstream direction, and the right direction in FIG. 1 may be referred to as a downstream direction. Also, the vertical direction in FIG. 1 may be referred to as the width direction.

  As shown in FIG. 2, the settling basin 1 is provided with a scum removing device 10, a sludge scraper 30, a drainage weir 40, and a sludge pit 50. The sludge scraping machine 30 is provided at both ends in the width direction of the sedimentation tank 1, and a pair of chains 31 that circulate and move in the sedimentation tank 1, and a plurality of flight plates 32 bridged between the pair of chains 31. And four sprockets 33 arranged for each chain 31. One of the sprockets 33 is rotationally driven clockwise in FIG. 2 by a motor (not shown). The chain 31 is rotated clockwise in FIG. 2 as the sprocket 33 rotates. The flight plate 32 is also rotated clockwise in FIG. The sludge deposited at the bottom of the settling basin 1 is scraped into the sludge pit 50 by the flight plate 32 moving in the upstream direction of the settling basin 1 near the bottom of the settling basin 1. The sludge scraped into the sludge pit 50 is discharged to the outside of the sedimentation tank 1 by a sludge pump (not shown). Further, in the vicinity of the water surface W of the sedimentation tank 1, the flight plate 32 moving in the downstream direction of the sedimentation tank 1 has an upper end projecting from the water surface and a lower end submerged in water. The scum floated on the water surface W of the sedimentation tank 1 is transferred by a flight plate 32 in the vicinity of the water surface W of the sedimentation tank 1 toward a weir 11 described later.

  FIG. 3 is an enlarged view of a portion B in which the portion B in FIG. 2 is enlarged. FIG. 4 is a schematic perspective view of the crucible 11, the trough 12, the connection member 13 and the lid 14 shown in FIG. 3. 5 is a side view of the trough 12 and the lid 14 as viewed from the left side in FIG.

  As shown in FIG. 3, the scum removing device 10 includes a weir 11, a trough 12, a connecting member 13 for connecting the weir 11 and the trough 12, a lid 14 and an opening / closing mechanism 15 for opening and closing the lid 14; A scum pit 16 is provided.

  As shown in FIGS. 3 and 4, the connection member 13 is configured of a fixing plate 131, a side plate 132, a sealing member 133, and a hook hinge 134. The fixing plate 131 is composed of a plate bottom portion 131a and a pair of side plate portions 131b provided at both widthwise end portions of the plate bottom portion 131a. Further, the sealing member 133 is composed of a bottom surface portion 133a and a pair of side surface portions 133b provided at both widthwise end portions of the bottom surface portion 133a. In FIG. 3, the direction orthogonal to the paper surface is the width direction. The side plates 132 are a pair of metal plates welded to both end surfaces in the width direction of the crucible 11. The fixing plate 131 is formed by bending a metal plate. The end face of the fixing plate 131 in the downstream direction is joined to the trough 12 by welding so that water can not enter from the joining portion. The downstream end of the seal member 133 is bonded to the fixing plate 131 so that water can not enter from the bonded portion. The seal member 133 is made of a rubber sheet material. In addition, the member which comprises the sealing member 133 should just be a sheet material which has softness, for example, may be a sheet material made of vinyl resin.

  The crucible 11 is composed of a triangular prism-shaped portion 11 b having a space inside and a projecting surface portion 11 c projecting in the downstream direction from the triangular prism-shaped portion 11 b. Further, both end surfaces in the width direction of the weir 11 are covered by a pair of side plates 132, and the weir 11 and each side plate 132 are joined by welding so that water can not enter into the inside of the triangular prism shaped portion 11b of the weir 11 There is. In addition, you may shape | mold integrally the weir 11 and the side plate 132, for example by bending-processing the metal plate of 1 sheet.

  The upstream end of the side surface portion 133 b of the seal member 133 is bonded to the side plate 132 so that water can not enter from the bonded portion. The upstream end of the bottom surface portion 133a of the seal member 133 is bonded to the projecting surface portion 11c of the weir 11 so that water can not enter from the bonded portion. The projecting surface portion 11 c of the weir 11 is rotatably attached to the plate bottom portion 131 a of the fixing plate 131 by a weir hinge 134. The hook hinge 134 is fixed to the projecting surface portion 11 c of the hook 11 and the plate bottom portion 131 a of the fixing plate 131 by bolts (not shown) so as to sandwich the bottom surface portion 133 a of the sealing member 133. As shown in FIG. 4, the side surface portion 133 b of the seal member 133 is folded in a bellows shape so as not to prevent the rotational movement of the crucible 11.

  The weir 11 is adjusted in buoyancy so as to be submerged in water for a predetermined distance from the water surface W. By the buoyancy of the weir 11, the distance from the water surface W to the upper end portion 11a of the weir 11 is always kept constant regardless of the water level of the sedimentation basin 1. In the present embodiment, the buoyancy of the weir 11 is adjusted such that the upper end portion 11a is submerged in water at a distance of 25 mm from the water surface W. In the following description, the distance from the water surface W to the upper end portion 11a of the weir 11 will be referred to as “sinking depth”. For example, when the position of the water surface W (water level of the sedimentation basin 1) changes to the position indicated by the two-dot chain line in FIG. 3, the weir 11 moves to the position indicated by the two-dot chain line with the fluctuation of the water surface W. Therefore, the water depth is always 25 mm.

  The upper surface downstream of the upper end portion 11 a of the weir 11 and the inner side surface of the connection member 13 form a pouring area 130 where the water of the sedimentation basin beyond the weir 11 is collected. The upper end portion of the side plate portion 131b of the fixing plate 131, the upper end portion of the side portion 133b of the seal member 133, and the upper end portion of the side plate 132 protrude above the water surface W. For this reason, the water of the sedimentation basin 1 does not enter the pouring area 130 beyond the side plate portion 131 b of the fixing plate 131, the side surface portion 133 b of the seal member 133, or the side plate 132. That is, only the water beyond the upper end portion 11 a of the weir 11 can flow into the burying area 130. With this configuration, scum present in the vicinity of the water surface W of the sedimentation basin 1 can be efficiently flowed into the introduction area 130.

  The trough 12 includes an upstream side plate 12a, a downstream side plate 12b, and a bottom plate 12c connecting the upstream side plate 12a and the downstream side plate 12b, and as shown in FIG. It has a shape. The upstream side plate 12a, the downstream side plate 12b, and the bottom plate 12c are formed by bending a single metal plate, but they may be separately formed and joined by welding or the like. The trough 12 extends in the width direction of the sedimentation tank 1, and the inner circumferential surface of the trough 12 forms a flow path 124 for flowing scum mixed water mixed with scum toward the outside of the sedimentation tank 1 . Further, the trough 12 extends to a scum pit 16 (see FIG. 1) provided outside the sedimentation basin 1. The bottom plate 12 c of the trough 12 is inclined slightly downward toward the outside of the sedimentation basin 1. As shown in FIG. 3, the upper portion of the upstream side plate 12 a of the trough 12 is an inclined surface which is inclined about 15 degrees in the downstream direction toward the upper side. The inclined surface is provided with an inflow port 125 through which scum mixed water beyond the upper end portion 11 a of the weir 11 passes when it flows into the flow path 124.

  As shown in FIG. 5, on the upstream side plate 12 a of the trough 12, three substantially rectangular inlets 125 having an R portion at a portion connecting the lower side and the side side are provided side by side in the width direction. The number of inlets 125 may be one, but by dividing into three, it is possible to reduce the size of each lid 14 closing each inlet 125. If the lid 14 is large, distortion generated in the lid 14 tends to be large. By making the lid 14 smaller and reducing the distortion generated in the lid 14, the sealing property of the inlet 125 by the lid 14 can be enhanced. The upper side of the inflow port 125 is provided at a position above the surface on which the water surface W (the water level represented by a solid line in FIG. 5) when the water level of the sedimentation tank 1 is the highest is located. In addition, the lower side of the inflow port 125 is provided at a position lower than the surface on which the water surface W (water level represented by a two-dot chain line in FIG. 5) when the water level of the sedimentation tank 1 is lowest is located. There is. In addition, the flow volume of the water which flows in into the sedimentation basin 1 is managed by the management system which is not shown in figure, and the fluctuation | variation of the position of the water surface W of the sedimentation basin 1 is about 50 mm at maximum.

  From the inflow port 125, scum mixed water having a flow rate equal to or higher than the flow rate of the scum mixed water flowing over the upper end portion 11a of the weir 11 into the pouring area 130 can pass through the flow path 124. That is, the total opening area of the three inlets 125 is set to be equal to or larger than the area obtained by multiplying the length in the width direction of the weir 11 by the water depth. By setting it as such an opening area, the mixing rate of the scum of the scum mixing water which flows in into the flow path 124 can be raised. This is because, when the lid 14 is opened, scum mixed water having a flow rate equal to or higher than the flow rate of scum mixed water flowing into the pouring area 130 flows out from the pouring area 130 through the inflow port 125 and flows out. This is because the water level of scum mixed water existing at 130 drops. When the water level of the scum mixed water is lowered, the scum floating near the water surface W of the sedimentation tank 1 can be efficiently made to flow into the introduction area 130, and more scum mixed water near the water surface of the introduction area 130 It can flow into the channel 124 from the inlet 125.

  It is desirable that the distance h between the upper side and the lower side of the inflow port 125 be 1.5 times or more as large as the depth of immersion (here, 25 mm). By doing this, even if the length in the width direction of the inflow port 125 is shortened, the flow rate of scum mixed water flowing into the flow path 124 can be secured. When the length in the width direction of the inlet 125 is shortened, the length in the width direction required for the lid 14 is shortened, and the inlet 125 is highly sealed by using the lid 14 with small distortion in the width direction. It becomes possible to be closed.

  As shown in FIG. 4, the inlet 125 is provided with a packing 126 so as to surround the side and lower side thereof. When the inlet 125 is closed by the lid 14, the lid 14 and the packing 126 are in contact with each other, so the sealing performance between the lid 14 and the inlet 125 can be enhanced. The packing 126 is a P-packing in which a portion in contact with the lid 14 has a hollow cylindrical shape.

  The three lids 14 for opening and closing each inlet 125 are rotatably mounted on the upstream side plate 12a by the lid hinges 141 fixed to the upstream side plate 12a of the trough 12 via the pedestals 147 for adjusting the mounting height. It is attached. The lid 14 has an upper end portion at a position higher than the water surface W. When the lid 14 closes the inlet 125, the lower end of the lid 14 is at a position lower than the water surface W. The lid 14 is configured to open the inflow port 125 by rotating the lower portion submerged in water in a state of closing the inflow port 125 so as to move upward on the water surface side. With this configuration, it is possible to flow scum mixed water accumulated in the pouring area 130 into the flow path 124 only by opening the lid 14 a little.

  As shown in FIG. 3, an opening / closing mechanism 15 for opening and closing the lid 14 is connected to the lid 14. The opening and closing mechanism 15 is provided for each of the three lids 14 one by one. The open / close mechanism 15 is configured of an electric valve 151, a water storage tank 152, a fulcrum 153, a first link 154, a second link 155, and a third link 156. The third link 156 is rotatably connected to the lid 14, and each link is rotatably connected to each other. The motor-operated valve 151 is connected to a pipe for sending the water treated at the sewage treatment plant, and when the motor-operated valve 151 is opened, water is supplied from the pipe to the water storage tank 152. The water storage tank 152 has a small hole (not shown) at the bottom. The small holes are for discharging the water in the water storage tank 152 little by little. When the water in the water storage tank 152 runs low, the rotational moment generated by the weight of the water storage tank 152 decreases and the first link 154 rotates counterclockwise in FIG. 3, and the opening / closing mechanism 15 and the lid 14 in FIG. 3 It becomes the position shown by the solid line.

  The motor operated valve 151 is opened, for example, at an hour interval for 3 minutes in response to a signal from a timer (not shown). By adjusting the timer, this time interval and the time to open can be set arbitrarily. The opening and closing mechanisms 15 connected to the respective lids 14 operate automatically in response to a signal from the same timer, and the three opening and closing mechanisms 15 open and close almost simultaneously. The three lids 14 may be simultaneously operated by one opening / closing mechanism 15 without providing the opening / closing mechanism 15 in each lid 14 respectively. When the motor-operated valve 151 is opened, water flows into the water storage tank 152, and the weight of the water storage tank 152 is increased by the flowed-in water. When the weight of the water storage tank 152 exceeds a predetermined amount, the first link 154 rotates clockwise in FIG. 3 about the fulcrum 153, and the second link 155 and the third link 156 are lifted upward. Then, the lid 14 rotates to the position shown by the broken line in FIG. 3 around the rotation center of the lid hinge 141, and the inflow port 125 is opened. The scum mixed water which has flowed into the flow path 124 from the opened inlet 125 flows to the scum pit 16 shown in FIG.

  FIG. 6 is a cross-sectional view showing the scum pit 16.

  The scum pit 16 is provided with a pump 161 having a suction port 162 near the bottom surface of the scum pit 16. The pump 161 pumps up scum mixed water accumulated in the scum pit 16 and discharges it out of the scum removing device. That is, the pump 161 in the present embodiment corresponds to an example of the discharge unit, and the pump 161 is a scum removing device, and the downstream side of the pump 161 corresponds to the outside of the scum removing device. Since the scum tends to float on the water surface, it is desirable that the water surface of the scum mixed water come to a position where the suction port 162 is provided in order to pump up the scum efficiently. The total flow rate of the scum mixed water flowing into the flow path 124 from the three inlets 125 of the present embodiment is limited so as to be equal to or less than the pumping flow rate that the pump 161 pumps up. That is, the total opening area of the three inlets 125 is set to be an area such that the total flow rate of scum mixed water flowing into the flow path 124 is equal to or less than the pumping flow rate pumped by the pump 161. By providing the inflow port 125, the flow rate of the scum mixed water flowing into the flow path 124 can be limited, and the water surface of the scum mixed water in the scum pit 16 can be maintained at the position where the suction port 162 exists. In addition, it can be reliably prevented that scum mixed water overflows from the flow path 124 and flows back to the sedimentation tank 1. As described above, according to the scum removing device 10 of the present embodiment, the scum mixed water flowing into the flow path 124 formed by the trough 12 can be set to an appropriate flow rate. Further, in the scum removing device 10 of the present embodiment, since the lid 14 is driven to open and close by the water flowing into the water storage tank 152, a new power source such as an actuator for opening and closing the lid 14 is not required (so-called No power). In addition, since the suction depth is made constant by the buoyancy of the weir 11, water from the water surface to a certain depth can be made to flow into the flow path at a constant flow rate with the scum only by opening the lid 14.

  From the scum removing device of the present embodiment, the scum removing device for flowing scum mixed water mixed with scum floating on the water surface of the settling tank to a pump outside the settling pool, extending toward the outside of the settling pool And a trough that forms a flow path into which scum mixed water flows in, an upper end portion of the trough which is sunk from the water surface, and the trough is provided so as to be able to close the trough; And an inflow port passing through the flow path, wherein the inflow port restricts the flow rate of the scum mixed water flowing into the flow path to a value equal to or less than the pumping flow rate of the pump. Inventive ideas such as removal devices can be derived. In the present inventive concept, the scum removing device need not necessarily be provided with the scum pit 16.

  Next, the scum removing device 10 of another embodiment will be described. In the following description of the embodiment, the description overlapping with the description of the scum removing device 10 of the previous embodiment is omitted.

  FIG. 7 is a cross-sectional view showing the scum pit 16 in the scum removing device 10 of another embodiment.

  In the previous embodiment, the scum mixed water in the scum pit 16 was discharged out of the scum removing device using the pump 161, but in this embodiment, the scum mixed water is removed from the scum by the natural flow from the discharge port 165. The difference is that it is discharged outside. As shown in FIG. 7, the bottom of the scum pit 16 is provided with a discharge port 165 corresponding to an example of the discharge means. In the scum removing device of this embodiment, the discharge port 165 is the scum removing device, and the downstream side of the discharge port 165 corresponds to the outside of the scum removing device. In the present embodiment, the total flow rate of the scum mixed water flowing into the flow path 124 from the three inlets 125 is equal to or less than the flow rate of the scum mixed water discharged from the discharge port 165 to the outside of the scum removing device. It is restricted. That is, the total opening area of the three inlets 125 is made to be equal to or less than the opening area of the outlet 165. In the present embodiment, the discharge port 165 is provided on the bottom surface of the scum pit 16, but may be provided on the side surface of the scum pit 16.

  Also in this embodiment, the same effect as the previous embodiment can be obtained. Further, since the pump 161 is not used, power consumption is reduced.

  The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the claims. For example, in the present embodiment, the opening / closing mechanism 15 is provided to change the weight of the water storage tank 152 by the water flowing into the water storage tank 152 to open and close the lid 14. However, the lid 14 is opened and closed by an actuator such as a motor. You may In addition, the lid 14 may be opened and closed using the movement of the flight plate 32 when moving to the predetermined position. Further, although the example in which the rotary lid 14 is provided has been described, the sliding lid 14 may be configured to move along a plane formed by the inlet 125. Furthermore, the position of the sliding lid 14 in the sliding direction may be position controlled using an actuator. By controlling the position of the sliding lid 14, the flow rate of scum mixed water flowing into the flow path 124 can be arbitrarily adjusted. For example, by controlling the position of the lid 14 in accordance with the amount of scum mixed water in the scum pit 16, the flow rate of the scum mixed water flowing into the flow path 124 may be adjusted. Also, for example, when the ingested water depth fluctuates due to some cause, the flow rate of scum mixed water flowing into the flow path 124 may be adjusted by position control of the position of the lid 14 according to the fluctuated inundated water depth. . Further, in the present embodiment, the sinking water depth is fixed by the buoyancy of the weir 11, but a float floating on the water surface separate from the weir 11 may be provided, and the weir 11 may be suspended from the float. In addition, even if it is the component contained only in each description of each embodiment and modification which were demonstrated above, you may apply the component to another embodiment and modification.

The scum removing apparatus described above is a scum removing apparatus for flowing scum mixed water mixed with scum floating on the water surface of the settling tank to the outside of the settling pool,
A trough extending toward the outside of the sedimentation tank to form a flow path into which scum mixed water flows in;
Discharge means provided outside the settling tank and discharging scum mixed water flowing through the flow path out of the scum removing device;
The upper end portion of the weir which is sunk from the water surface,
An inlet which is occludably provided in the trough and through which scum mixed water beyond the upper end portion of the weir flows as it flows into the flow path;
A lid closing the inlet;
The weir maintains the upper end portion at a position submerged in water for a predetermined distance from the water surface even if the water level of the sedimentation tank changes,
The inflow port can pass scum mixed water having a flow rate higher than the flow rate of scum mixed water exceeding the upper end portion,
The lid is capable of adjusting the flow rate of scum mixed water flowing into the flow passage through the inlet, and the discharge means discharges the flow rate of scum mixed water flowing into the flow passage It is characterized in that it is limited to the following flow rate.

Furthermore, in the scum removing device, the scum mixed water mixed with scum floating on the surface of the settling basin is flowed toward the outside of the settling basin,
A trough extending toward the outside of the sedimentation tank to form a flow path into which scum mixed water flows in;
Discharge means provided outside the settling tank and discharging scum mixed water flowing through the flow path out of the scum removing device;
The upper end portion of the weir which is sunk from the water surface,
And an inlet, which is provided in the trough so as to be closable and through which scum mixed water beyond the upper end portion of the weir flows when it flows into the flow path,
The inflow port may be characterized in that the flow rate of scum mixed water flowing into the flow path is limited to a flow rate or less discharged by the discharge means.

  According to the above scum removing device, even if the distance from the water surface to the upper end portion of the weir changes, the flow rate of scum mixed water flowing into the flow path is limited by the inflow port. It can prevent overflowing.

In the above scum removing device, the weir maintains the upper end portion at a position submerged in water for a predetermined distance from the water surface even if the water level of the sedimentation tank changes,
The inflow port is characterized in that scum mixed water having a flow rate higher than the flow rate of scum mixed water exceeding the upper end portion can pass.

  By doing this, water from the water surface to a certain depth from the water surface can be made to flow into the flow path together with the scum regardless of the change in water level, and the scum mixing rate of the scum mixed water flowing into the flow path can be increased.

  In the scum removing device, the inflow port may be divided into a plurality of openings along a direction in which the trough extends.

Furthermore, the scum removing device further comprises a lid closing the inlet.
Preferably, the lid is capable of adjusting the flow rate of scum mixed water flowing into the flow passage through the inlet.

  By adjusting the flow rate of scum mixed water flowing into the flow path, even if the distance from the water surface to the upper end of the weir fluctuates for some reason, the scum mixed water flows into the flow path according to the changed distance Flow rate can be an appropriate amount.

  In addition, dividing the inlet into a plurality of openings makes it possible to reduce the size of the lid to reduce the distortion generated in the lid and to improve the sealing property of the inlet by the lid.

Furthermore, the scum removal device described so far
In a scum removing device for flowing scum mixed water mixed with scum floating on the water surface of a sedimentation basin to the outside of the sedimentation basin,
A trough extending toward the outside of the sedimentation tank to form a flow path into which scum mixed water flows in;
The upper end portion of the weir which is sunk from the water surface,
A connecting member connecting the trough and the weir;
An inlet which is occludably provided in the trough and through which scum mixed water beyond the upper end portion of the weir flows as it flows into the flow path;
And a lid closing the inlet.
The connection member has a seal member and a hinge made of a flexible sheet material.
The weir may be rotated by the hinge, and the upper end portion may be maintained at a position submerged in water for a predetermined distance from the water surface even if the water level of the sedimentation tank changes.

In the scum removing device, the seal member may have a bottom surface portion and a pair of side surface portions provided at both widthwise end portions of the bottom surface portion. Further, in the scum removing device, the inlet may be divided into a plurality of openings along a direction in which the trough extends.

Also, the scum removal method described so far is
In a scum removing method for removing scum using a scum removing device for flowing scum mixed water mixed with scum floating on the water surface of a settling basin to the outside of the settling basin,
The scum removing device
A trough extending toward the outside of the sedimentation tank to form a flow path into which scum mixed water flows in;
The upper end portion of the weir which is sunk from the water surface,
A connecting member connecting the trough and the weir;
An inlet which is occludably provided in the trough and through which scum mixed water beyond the upper end portion of the weir flows as it flows into the flow path;
And a lid closing the inlet.
Even if the water level of the sedimentation tank changes, the upper end of the weir is maintained at a position submerged in the water for a predetermined distance from the water surface, and scum mixed water upstream of the upper end of the weir is the upper end of the weir And sinking downstream of the upper end of the bowl by
The scum mixed water pumped downstream of the upper end portion of the weir has an inflow step of opening the lid during execution of the wicking step and flowing into the trough from the inflow port. Good.

  Further, in this scum removing method, the scum may be removed using the scum removing device in which the connection member has a seal member made of a flexible sheet material and a hinge.

  Further, in this scum removing method, the scum is removed using the scum removing device, wherein the seal member has a bottom surface portion and a pair of side surface portions provided at both widthwise end portions of the bottom surface portion. May be

  Furthermore, in this scum removing method, the scum may be removed using the scum removing device in which the inlet is divided into a plurality of openings along the direction in which the trough extends.

DESCRIPTION OF SYMBOLS 1 sedimentation tank 10 scum removal apparatus 11 square 12 trough 124 flow path 125 inlet 14 lid 15 opening-and-closing mechanism 161 pump

Claims (2)

A trough extending toward the outside of the sedimentation tank to form a flow path into which the scum mixed water flows, an inlet through which the scum mixed water provided in the trough passes when flowing into the flow path, and the flow A scum removing method for removing scum using a scum removing device comprising a lid for opening and closing an inlet, and a discharging means provided outside the settling tank and discharging scum mixed water flowing through the flow path In
Opening the lid;
Closing the lid body ;
Even if the water level of the sedimentation tank changes, the upper end portion of the weir connected to the trough is maintained at a position submerged in the water a predetermined distance from the water surface of the sedimentation tank, and the scum upstream of the upper end portion of the weir And d) mixing the mixed water with the upper end portion of the weir above the upper end portion of the weir .
The opening step and the closing step are performed such that the amount of inflow of scum mixed water flowing into the flow path by the opening of the lid does not exceed the amount of discharge of the discharging means .
A method for removing scum, wherein the scum mixed water entrained on the downstream side of the upper end portion of the weir flows into the flow path from the inflow port by executing the open step .   The scum removing method according to claim 1, wherein the opening step is a step of opening the lid to a range in which the inflow amount does not exceed the discharge amount.

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