JP4990856B2 - Scum remover - Google Patents

Description

The present invention relates to a scum removing apparatus equipped with a pipe gap, dirty water to precipitate separation processing raw water after biological processing, to a suitable scum removing apparatus in a so-called settling tank.

  Conventionally, in a scum removing device provided with this type of pipe skimmer, the pipe skimmer is installed in such a manner that a part of the pipe skimmer is submerged in the water surface on the downstream side of the water tank where the scum is generated. For example, if the tank is a sedimentation basin of a sewage treatment facility such as sewage, the pipe skimmer is partially submerged in front of the supernatant water extraction side that is provided on the side opposite to the raw water inflow side of the sedimentation basin. is set up.

  This conventional pipe clearance is made of a pipe material having a length equal to the width of the water channel in a direction perpendicular to the water flow direction of the settling basin, and the pipe material is provided with an opening (notch) opened in the axial direction. ing. The pipe skimmer is provided with a rotation mechanism that rotates about the longitudinal axis, and is rotated so that a part of the opening is submerged in water when the scum is removed. It is comprised so that it may flow in into a pipe clearance from a part.

  In a scum removing device provided with a pipe skimmer, the removal of scum is performed in association with a water flow. That is, at the time of scum removal, a part of the opening of the pipe skimmer is located in the water, so that water starts to flow into the pipe skimmer through the opening. The scum that has floated on the surface of the water as a result of this flow of water also flows into the pipe skimmer, thereby removing the scum.

  By the way, normally, the flow of water in the water tank in which scum is generated is not fast. For example, when the water tank is a sedimentation basin of a sewage treatment facility, the flow rate is about 3 to 5 cm / sec. If the scum is removed only by the flow of the scum, there is a problem that the discharge time of the scum becomes long. Moreover, in the case of a scum that is inferior in fluidity, there is a problem that the discharge time becomes longer.

  The longer scum discharge time means that the amount of water discharged increases with scum discharge. Since the discharged water is separated from the scum and then returned to the raw water side, there is a problem that the load on the sewage treatment facility is increased.

  In the case where scum is discharged only by the flow of water, there are problems as described above, and various proposals have been made to solve this problem. For example, Patent Document 1 discloses a nozzle tube provided in the water upstream of the position of the opening when the scum is removed so that a part of the opening of the pipe skimmer is submerged in the water. It is disclosed that air is blown out toward the opening to enhance the movement of the scum.

Patent Document 2 discloses that a spray nozzle is provided at an upper position of the scum, and pressure water is ejected obliquely downward from the spray nozzle to impart a moving force to the scum.
Japanese Utility Model Publication No. 53-88071 Japanese Patent Laid-Open No. 9-276860

  However, when the generated scum floating on the water surface is in a thin film shape, for example, in the case of a thin film scum generated in the final sedimentation basin of a sewage treatment facility, as shown in Patent Document 1 or Patent Document 2 above The scum moving means cannot be used at all.

  For example, it is difficult to increase the movement of the scum by ejecting air from a nozzle pipe provided in the upstream water in the opening of the pipe skimmer of Patent Document 1. This is because the thin film scum floating on the surface of the water floats with a very delicate force relationship, so when air is ejected from the bottom of the scum, turbulence occurs in the water flow, and the scum flocks. This is because the scum mixed in the water rises again at the position moved below the pipe clearance and is discharged and contained in the supernatant water, resulting in a decrease in the quality of the discharged water.

  Similarly, even if pressure water for transfer is jetted onto the upper surface of the scum shown in Patent Document 2, it is difficult to employ because turbulent flow is generated in the water flow to flock the scum.

  Therefore, the present invention has been made to solve the above-described drawbacks, and the object is to efficiently discharge the scum into the pipe skimmer in a short time even when the scum is in the form of a thin film floating on the water surface. It is an object of the present invention to provide a scum removing device that can be used.

In order to achieve the above object, a scum removing device according to an embodiment of the present invention is a scum removing device provided with a pipe skimmer, which forms an opening provided in the pipe skimmer. On the lower side, when the opening is located on the water surface, a guide piece extending a predetermined length is provided upstream of the water flow while maintaining a depth where the tip is located below the scum generated on the water surface. In addition, at a predetermined position on the upstream side of the water flow with respect to the position of the front end of the guide piece, there is provided an ejection means for ejecting water toward the opening when a part of the opening is located in the water. The water flow is at the time of sedimentation treatment after biological treatment of sewage, and the installation position of the ejection means is a predetermined distance away from the tip position of the guide piece , and the ejection means While the pipe squirts water Part of the opening of the is characterized in that located in the water is rotated by the rotational driving mechanism.

In the above configuration, when water is ejected from the ejection means toward the opening, a water flow having a fast flow toward the opening is generated on the upper surface of the guide piece.
Further, in the scum removing device according to an embodiment of the present invention, the joint portion between the lower side forming the opening of the pipe skimmer and the guide piece is formed in a curved shape protruding upward. Yes.

The scum removing device according to the present embodiment is characterized in that the pipe skimmer is made of a pipe material having a circular cross section.
Furthermore, the pipe skimmer is characterized in that it is made of a pipe material having a rectangular cross-sectional shape.

According to the scum removing device of the present invention, it is possible to generate a water flow having a higher flow velocity than the periphery facing the opening on the upper surface side of the guide piece, and flock the scum together with the fast water flow. And can be reliably moved to the opening in a short time. In particular, in the case of sedimentation treatment after the water stream biologically treats sewage, that is, when applied to the final sedimentation basin of the sewage treatment facility, it is possible to prevent the quality of the discharged treated water from deteriorating, The amount of water accompanying the scum discharge is small, and an extremely excellent effect that energy saving can be achieved can be obtained.
For this reason, while being able to prevent the quality of the treated water discharged | emitted from being deteriorated, the amount of water accompanying scum discharge can be reduced and energy saving can be achieved.
Further, in the scum removing device according to the present invention, the joint portion between the lower side forming the opening of the pipe skimmer and the guide piece is formed in a curved shape protruding upward, that is, the joint portion is “R”. Since it is formed, there is no disturbance of the water flow from the top of the guide piece into the pipe skimmer, the water flow accompanied by the scum is smoothly performed, and the scum can be discharged efficiently.

  And according to the scum removal apparatus which concerns on this invention, since the cross-sectional shape of the pipe material of a pipe skimmer consists of a circle or a rectangle, it can implement easily. In particular, when the cross-sectional shape of the pipe material is rectangular, the capacity in the pipe skimmer is large, and the scum in the pipe skimmer can be moved more smoothly.

The best mode for carrying out the present invention will be described below in detail with reference to the drawings. FIG. 1 is a plan view of a final sedimentation basin of a sewage treatment facility equipped with a scum removing device according to an embodiment of the present invention, and FIG. 2A is an opening of a pipe skimmer according to the present embodiment. FIG. 1B is an enlarged cross-sectional view taken along line X ₁ -X _{1 in} FIG. 1 when the portion is located on the water surface. FIG. _{1 is} an enlarged cross-sectional view taken along line X ₁ -X ₁ in FIG. 1, and FIG. 3 is an X ₂ -X _{2 line in} FIG. 1 when the opening of the pipe skimmer of the present embodiment is located on the water surface. 4 is a cross-sectional view taken along line X ₂ -X _{2 in} FIG. 1 when a part of the opening of the pipe skimmer according to the present embodiment is located in water.

  In the figure, reference numeral 1 denotes a final sedimentation basin (hereinafter, referred to as “sedimentation basin”) of a sewage treatment facility to which a scum removing device having a pipe skimmer according to an embodiment of the present invention is applied. Here, a portion of the sedimentation basin 1 on the supernatant water extraction part 2 side is shown.

  In the illustrated sedimentation basin 1, water is configured to flow from the left side to the right side. The sedimentation basin 1 is provided with a sludge scraping mechanism for discharging the settled sludge, as in the known sedimentation basin 1, but the detailed description is omitted because it is not related to the description of the present embodiment. In an actual sewage treatment facility, a plurality of sedimentation basins are provided, but only one sedimentation basin is shown here to simplify the drawing.

In the figure, a ₁ is a pipe clearance, which is partially submerged in the front side of the supernatant water extraction part 2 of the sedimentation basin 1, that is, a predetermined distance upstream from the supernatant water extraction part 2. It is provided over the entire channel width in the direction orthogonal to the water flow direction.

One end portion (upper end portion in FIG. 1) of the pipe skimmer a ₁ is located in the scum pit 3 that penetrates one tank wall of the settling basin 1 and is provided outside the tank wall, and is opened. The water including the scum can be discharged into the scum pit 3 from the one end portion.

The other end portion of the pipe skimmer a ₁ formed in a closed shape is rotatably supported on the other tank wall of the settling basin 1, and the axis of the pipe skimmer a ₁ is centered on the support shaft. A rotation drive mechanism 4 is provided for rotation.

Incidentally, the support shaft portion that penetrates the portion and the other end side of the bath wall through the one end side of the bath wall of the pipe clearance a _1, together are configured to allow rotation of the respective tank wall as a bearing, its The mechanisms of the bearings are each configured to be watertight, and are devised so that water in the sedimentation basin 1 does not leak.

The pipe clearance a ₁ is in the direction of slightly longer length than waterway width perpendicular to the water flow direction of the settling basin 1, and it is the cross-sectional shape from a circular pipe member P _1, to its pipe P _1, An opening (notch) 5 opened in the axial direction is provided. The inner diameter of the pipe material P ₁ is determined so that water including the scum taken in from the opening 5 can be quickly discharged into the scum pit 3.

In the figure, 6 is a plate-shaped guide piece having a rectangular planar shape made of steel or synthetic resin, and is a predetermined distance from the position of the lower side forming the opening 5 of the pipe material P ₁ toward the upstream side. (Distance corresponding to the short side length of the rectangle toward the left side in FIG. 1) is provided to extend. That is, the guide piece 6 has one end side (the right side in FIG. 1) joined to the lower side forming the opening 5.

Then, the side (front end portion of the guide piece 6) and the other end side, regardless of the rotational position of the pipe clearance a _1, located in the water near the water, located always below the scum S generated on the water surface It is decided so. Further, the joint between the lower side of the opening 5 and the guide piece 6 is formed in a curved shape protruding upward, so-called “R”. This “R” is indicated by (R) in the drawing.

  In the figure, 7 is a pressure water supply pipe provided in the water near the water surface, and is a predetermined distance upstream from the position of the tip of the guide piece 6 and a direction orthogonal to the water flow direction of the settling basin 1. Is provided. The pressure water supply pipe 7 is provided with ejection nozzles 8, 8,... At a predetermined interval.

These jet nozzles 8, 8, ... injection direction of the pressure water is the upper surface of the plate-shaped guide piece 6, and are determined to face the lower side of the opening 5 of the pipe gap a _1. The pressure of the pressure water ejected from the ejection nozzles 8, 8,... And the amount of the water are determined to be sufficient to promote the flow of water toward the opening 5 on the upper surface side of the guide piece 6.

Next, the scum removing operation in the scum removing device of the present embodiment having the above-described configuration will be described. Now, when the sedimentation basin 1 is performing a sedimentation process and the pipe skimmer a ₁ is positioned on the water surface as shown in FIGS. 2 (a) and 3, the pipe skimmer a ₁ A thin film-like scum S is generated on the upstream water surface.

When the generation of the scum S shows a certain area, the pipe skimmer a ₁ is rotated via the rotation drive mechanism 4 so that a part of the opening 5 is located in the water (so as to be submerged in the water). Then, the pressure water is supplied to the pressure water supply pipe 7 through a pump (not shown) (see FIGS. 2B and 4).

Therefore, the pressure water is ejected from the ejection nozzles 8, 8 toward the opening 5, whereby the flow of water toward the opening 5 is promoted on the upper surface side of the guide piece 6. Then, the scum S is moved into the pipe skimmer a _{1 along} with the water whose speed has been increased while maintaining a thin film shape without being flocked, and is sucked into the opening 5.

The timing for rotating a part of the opening 5 to be located in the water via the rotation drive mechanism 4 and the time for the part to be located in the water are the experiments because the scum S generated by the water quality flowing into the sedimentation basin 1 is not uniform. It is desirable to be determined by In other words, it is desirable to determine the scum S by observing the discharge state of the scum S manually once a day for the first few days of operation of the apparatus.
Thereafter, automatic operation is performed based on the observation result.

  However, the start control of the automatic operation is not limited to the above example. A scum detection sensor is arranged on a predetermined surface of the settling basin 1 to detect that the scum is filled up to the scum detection sensor arrangement position. Alternatively, a plurality of detection sensors may be arranged so that scum removal is automatically performed when a predetermined sensor detects scum at the same time.

  The timing for supplying pressure water to the pressure water supply pipe 7 in automatic operation and injecting the pressure water from the ejection nozzles 8, 8,... Toward the opening 5 is synchronized with the timing for positioning a part of the opening 5 in water. To be controlled. In addition, the timing which positions a part of opening part 5 in water, and the timing which injects pressure water toward the opening part 5 from the ejection nozzles 8,8, ... are not limited at the time of automatic operation, but are always performed manually. It is desirable to configure so that it can. .

In particular, in the scum removing device having the above-described configuration, since the joint portion between the lower side of the opening 5 and the guide piece 6 is formed as “R” protruding upward, the water flow rectifying effect is excellent. . Therefore, it is possible to create a state in which the flow of water containing the scum S is sucked into the pipe skimmer a ₁ , and thereby the discharge of the scum S can be completed in a shorter time. The rectifying effect when “R” is formed at the joint between the lower side of the opening 5 and the guide piece 6 has been confirmed by experiments.

Scum S that has flowed into the pipe gap a ₁ is discharged to Sukamupitto 3 through the pipe gap a _1, scum S in this Sukamupitto 3 is processed by the processing means of the sludge processor or the like not shown. Moreover, the supernatant water (processed water) discharged | emitted by the supernatant water extraction part 2 is discharged to water systems, such as a river.

  The scum removing device having the above configuration can move the scum S to the opening 5 in a short period of time without causing the scum S to be flocked and with a fast water flow. As a result, the amount of water accompanying the discharge of the scum S can be reduced, and energy saving can be achieved.

FIG. 5 is a plan view of a sedimentation basin provided with a scum removing device according to another embodiment of the present invention, and FIG. 6 is a diagram illustrating the position of an opening of a pipe skimmer according to another embodiment on the water surface. 5 is a cross-sectional view taken along line X ₃ -X _{3 in} FIG. 5, and FIG. 7 is a cross-sectional view of FIG. 5 when a part of the opening of the pipe skimmer according to another embodiment is located in water. FIG. _{3 is} a cross-sectional view taken along line ₃ -X ₃ .

The scum removing device of another embodiment is a pipe having a rectangular cross section, whereas the scum removing device of the first embodiment described above has a circular cross section of the pipe material P _1. It is characterized by having a pipe clearance a ₂ using a material P ₂ .

The pipe material P _2, since the cross section of the pipe P ₂ is a rectangular, circumference the portion that is pivotally supported by the sedimentation tank 1 of the bath wall of Sukamupitto 3 side provided with a circular shaft member P ₂ ' It has been. Therefore, the pipe skimmer a ₂ can be easily rotated by the shaft member P ₂ ′ having a circular outer periphery.

The scum removing device according to another embodiment, like the scum removing device according to the first embodiment described above, can be opened in a short time without causing the scum S to be flocked and accompanied by a fast water flow. Since it can be moved to the part 5, it is possible to prevent deterioration of the quality of the discharged treated water, and the amount of water associated with the discharge of the scum S can be reduced, and energy saving can be achieved. In addition, since the pipe member P ₂ has a rectangular cross-sectional shape, the capacity of the pipe skimmer a ₂ is large, and therefore the water including the scum S in the pipe skimmer a ₂ can be moved more smoothly. The feature that it can be performed can be obtained.

  The scum removing device according to the embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to the above two embodiments, and the gist of the present invention is described. Design changes can be made without departing from the scope.

  For example, in the above-described example, the scum removing device is applied to the final settling basin of the sewage treatment facility, but the settling basin may be the first settling basin or other settling basin for factory wastewater. Furthermore, the present invention can be applied to a recovery tank that floats and separates valuable materials. In the case of this recovery tank, the fluid may not be water, but the “water” of the present invention includes such a fluid.

It is a top view of a sedimentation basin provided with the scum removal apparatus concerning the example of one embodiment concerning the present invention. (A) is an enlarged sectional view taken along line X ₁ -X ₁ of FIG. 1 when the opening of the pipe skimmer according to the present embodiment is located on the water surface, and (b) is an opening of the pipe skimmer. part is an enlarged cross-sectional view of X ₁ -X ₁ line in Figure 1 when positioned in the water.

Opening of the pipe clearance of Embodiment is a sectional view of X ₂ -X ₂ line in FIG. 1 when positioned on the water surface. Part of the opening of the pipe clearance of Embodiment is a sectional view of X ₂ -X ₂ line in FIG. 1 when positioned in the water.

It is a top view of the sedimentation basin provided with the scum removal apparatus of the other example of embodiment which concerns on this invention. Is a sectional view of X ₃ -X ₃ line in FIG. 5 when the opening of the pipe gap of another example of the embodiment is located on the water surface. Part of the opening of the pipe gap of another example of the embodiment is a sectional view of X ₃ -X ₃ line in FIG. 5 when positioned in the water.

Explanation of symbols

1 Sedimentation basin (final sedimentation basin)
2 Supernatant water extraction part 3 Scum pit 4 Rotation drive mechanism 5 Opening part 6 Guide piece 7 Pressure water supply pipe 8 Jet nozzle 8
a ₁ , a ₂ pipe clearance P ₁ , P ₂ pipe material P ₂ ′ shaft member S scum

Claims (4)

A scum removing device having a pipe clearance,
In the lower side forming the opening provided in the pipe skimmer, when the opening is located on the water surface, the tip is kept at a depth located below the scum generated on the water surface. A guide piece extending a predetermined length is provided on the upstream side of the water flow, and the opening is located at a predetermined position on the upstream side of the water flow with respect to the position of the tip of the water flow when a part of the opening is located in the water. A jetting means for jetting water toward the part,
The water flow is at the time of sedimentation treatment after biological treatment of sewage, the installation position of the ejection means is a predetermined distance from the position of the tip of the guide piece , and the ejection means is water. The scum removing device is characterized in that a part of the opening of the pipe skimmer is rotated by a rotary drive mechanism and is located in the water during the jetting . The scum removing device according to claim 1,
The scum removing device, wherein a joint portion between the lower side forming the opening and the guide piece is formed in a curved shape protruding upward. The scum removing device according to claim 1 or 2,
The pipe skimmer is made of a pipe material having a circular cross section. The scum removing device according to claim 1 or 2,
The pipe skimmer is made of a pipe material having a rectangular cross-sectional shape.

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