JP5443260B2 - Ejection nozzle for scum removal device - Google Patents

Description

  The present invention relates to an ejection nozzle for a scum removing device used in a scum removing device having a pipe clearance.

  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 in which 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 water channel width in a direction orthogonal 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.

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 the pressure water for transfer is ejected on the upper surface of the scum shown in Patent Document 2, it is difficult to adopt because the scum is flocked by generating a turbulent flow in the water flow.

Therefore, the present applicant has proposed a scum removing device shown in Patent Document 3 in order to solve the above-mentioned drawbacks. This scum removing device has a depth which is located below the scum generated on the water surface when the opening is located on the water surface at the lower side forming the opening provided in the pipe skimmer. When a guide plate extending a predetermined length is provided on the upstream side of the water flow while maintaining the thickness, and when a part of the opening is located in the water at a predetermined position on the upstream side of the water flow from the position of the tip of the guide plate In addition, water is ejected from the ejection nozzle toward the opening.
According to the scum removing device according to this proposal, a water flow having a higher flow velocity can be generated on the upper surface side of the guide plate compared to the periphery facing the opening, and the scum is flocked with the fast water flow. And can be reliably moved to the opening in a short time. 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. That is, the scum removing device according to this proposal has a property that can greatly contribute to so-called ecological measures.

Japanese Utility Model Publication No. 53-88071 Japanese Patent Laid-Open No. 9-276860 JP 2010-213933 A

  However, since the ejection nozzle of the scum removing device according to the above proposal is always located in water, there is a possibility that the inside of the ejection nozzle is soiled by scum or the like contained in water. In particular, when the scum removing device according to the above proposal is used in a sedimentation basin of a sewage treatment facility, since the concentration of contaminants contained in water is high, there is a problem that the inside of the ejection nozzle is easily damaged.

  Accordingly, the present invention has been made to solve the above-described drawbacks, and an object of the present invention is to provide an ejection nozzle for a scum removing device in which the interior of the ejection nozzle is not easily contaminated by scum or the like contained in water. There is to do.

In order to achieve the above object, the scum removing device ejecting nozzle according to the present invention is characterized in that the invention described in claim 1 is a scum removing device that ejects pressure water from the water toward an opening of a pipe skimmer of the scum removing device. A scum removal device jet nozzle main body provided with a closing member for closing the opening when pressure water is not ejected from the scum removal device jet nozzle main body. It is characterized by.
The ejection nozzle for the scum removing device according to claim 2 of the present invention is such that the closing member is made of a material that floats in water, and one end side of the closing member is pivotally supported so that the pressure is applied from the ejection nozzle main body for the scum removing device. It is characterized in that the opening is closed by buoyancy when water is not ejected .
The jet nozzle for a scum removing device according to claim 3 of the present invention is characterized in that the scum removing device is provided in a sedimentation basin for sedimentation treatment after biological treatment of sewage.

The ejection nozzle for a scum removal device according to claim 1 of the present invention is a closure that closes the opening of the ejection nozzle body for the scum removal device when pressure water is not ejected from the ejection nozzle body for the scum removal device. Since the member is provided, it is possible to effectively prevent the inside of the nozzle from being soiled by scum or the like contained in water.
In the jet nozzle for a scum removing device according to claim 2 of the present invention, since the closing member is made of a material that floats in water, the opening can be easily closed using the buoyancy .
The jet nozzle for a scum removing device according to claim 3 of the present invention is provided in a sedimentation basin in which the scum removing device performs sedimentation treatment after biological treatment of sewage, so that the scum can be flocked in a short time without flocking. And it can be reliably guided into the pipe clearance.

It is a top view of a sedimentation basin provided with the ejection nozzle for scum removal apparatuses concerning one embodiment of the present invention. (A) is a top view of the ejection nozzle for scum removal apparatuses which concerns on one embodiment of this invention, (b) is the figure when the pressure water is not ejected from the ejection nozzle for the scum removal apparatuses (a) X ₀ -X ₀ sectional view taken on line), (c) is the same X ₀ -X ₀ line sectional view of FIG. (a) when the pressure water is jetted from the scum removing apparatus for jetting nozzle. (A) is an enlarged sectional view taken along line X ₁ -X _{1 in} FIG. 1 when the opening of the pipe skimmer is located on the water surface, and (b) is a part of the opening of the pipe skimmer being underwater. is an enlarged sectional view of the X ₁ -X ₁ line in Figure 1 when located. Opening of the pipe gap is a cross-sectional view of the X ₂ -X ₂ line 1 when positioned on the water surface. Part of the opening of the pipe gap is a cross-sectional view of the X ₂ -X ₂ line in FIG. 1 when positioned in the water.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. FIG. 1 illustrates a final sedimentation basin (hereinafter “precipitation basin”) of a sewage treatment facility equipped with a scum removal device ejection nozzle (hereinafter referred to as “ejection nozzle”) according to an embodiment of the present invention. .) Is a plan view.

  In the 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 it is not related to the description of the present invention, so that detailed description thereof is omitted. 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 is a pipe clearance, and the water flow in the sedimentation basin 1 is such that a part of the sedimentation tank 1 is submerged in the front side of the supernatant water extraction part 2, that is, a predetermined distance upstream from the supernatant water extraction part 2. It is provided over the entire width of the water channel in the direction orthogonal to the direction.

  One end portion (upper end portion in FIG. 1) of the pipe skimmer a is located in a scum pit 3 that passes through 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.

And the other end part formed in the closed shape of the pipe skimmer a is pivotally supported by the other tank wall of the sedimentation basin 1, and the pivot is centered on the axis of the pipe skimmer a. A rotation drive mechanism 4 is provided for rotation.
In addition, the part which penetrates the tank wall of the one end part side of the pipe skimmer a, and the support shaft part which penetrates the tank wall of the other end part are each configured to be able to rotate with the tank wall as a bearing, and the bearings thereof. These mechanisms are each configured to be watertight, and are devised so that water in the sedimentation basin 1 does not leak.

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

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

  The other end side (the front end portion of the guide plate 6) side is located in the water near the water surface regardless of the rotational position of the pipe skimmer a, and is always located below the scum S generated on the water surface. (See FIGS. 3 to 5). Further, the joint portion between the lower side of the opening 5 and the guide plate 6 is formed in a curved shape, so-called “R”.

  In the figure, 7 is a pressure water supply pipe provided near the water surface, provided at a predetermined distance upstream from the position of the tip of the guide plate 6 and in a direction orthogonal to the water flow direction of the settling basin 1. It has been. The pressure water supply pipe 7 is provided with ejection nozzles 8, 8, and the like that hang down into the water via the connection pipe 9 at a predetermined interval.

  The jet direction of the pressure water of these jet nozzles 8, 8... Is determined so as to face the upper surface side of the plate-like guide plate 6 and the lower side of the opening 5 of the pipe skimmer a. 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 plate 6.

Since the configuration of each of the ejection nozzles 8, 8... Is the same, one ejection nozzle 8 will be described with reference to FIGS. 1A is a plan view of the ejection nozzle 8 corresponding to the ejection nozzle body of the present invention, and FIG. 1B is a diagram when pressure water is not ejected from the ejection nozzle 8. X ₀ -X ₀ line cross-sectional view of (a), FIG. (c) is a X ₀ -X ₀ line sectional view of FIG. (a) when the pressure water is jetted from the jetting nozzle 8 .

  As shown in FIG. 2A, the planar shape of the ejection nozzle 8 is formed such that the side from which pressurized water is ejected (the right side in FIG. 2A) is wide, and the pressure The side opposite to the side from which water is ejected is configured to be connected to the pressure water supply pipe 7 via the connecting pipe 9. Further, the cross-sectional shape of the ejection nozzle 8 is configured to form an elongated water channel, as shown in FIGS. 2 (b) and 2 (c). Therefore, the opening 10 that appears when the ejection nozzle 8 is viewed from the side where the pressure water is ejected has a slit shape parallel to the water surface of the sedimentation basin 1.

  In the figure, 11 is a closing member made of a material that floats in water, and one end side (the left end side in the illustrated example) is pivotally supported by a support shaft 12 on a bottom plate 8a that forms an ejection nozzle 8. ing. The closing member 11 can be easily made of foaming synthetic resin, and its size is determined so that the slit-shaped opening 10 can be closed.

  Accordingly, when the pressure water is not supplied from the pressure water supply pipe 7 to the ejection nozzle 8 through the connecting pipe 9, the closing member 11 itself is shown in FIG. When the pressure water is supplied from the pressure water supply pipe 7 through the connecting pipe 9 to the ejection nozzle 8 by rotating by the buoyant force of FIG. As shown by the arrow, the opening 10 can be opened by rotating with water pressure.

Next, the scum removing operation in the scum removing device of the present embodiment having the above-described configuration will be described with reference to FIGS. 3 (a) and 3 (b) to FIG. If the sedimentation basin 1 is performing a sedimentation process and the pipe skimmer a is positioned on the water surface as shown in FIGS. 3A and 4, the upstream side of the pipe skimmer a. A thin scum S is generated on the water surface.
In this state, since the openings 10 of the ejection nozzles 8, 8... Are closed by the closing members 11, the inside of the nozzles is contaminated with scum or the like contained in water so as to be blocked. Can be effectively prevented.

  When the generation of the scum S shows a certain area, the pipe skimmer a 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 immersed in the water). Then, the pressure water is supplied to the pressure water supply pipe 7 through a pump (not shown) (see FIGS. 2C, 3B, and 5). By the supply of the pressure water, the closing member 11 that has closed the opening 10 of the ejection nozzles 8, 8... Is opened by the water pressure, and the pressure water is ejected from the opening 10 (see FIG. 2C).

  Therefore, pressure water is ejected from the ejection nozzles 8, 8 toward the opening 5, thereby promoting the flow of water toward the opening 5 on the upper surface side of the guide plate 6. Then, the scum S is moved into the pipe skimmer a along with the accelerated flow of the water 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, scum removal may be performed automatically by arranging a plurality of various detection sensors.

  The timing of supplying pressure water to the pressure water supply pipe 7 and injecting the pressure water from the ejection nozzles 8, 8... Toward the opening 5 is controlled so as to be synchronized with the timing of positioning a part of the opening 5 in the water. Is done. 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 an automatic operation, but always carry out manually. It may be.

When the supply of pressure water from the pressure water supply pipe 7 to the ejection nozzles 8, 8... Is stopped, the openings 10 of the ejection nozzles 8, 8. It is effectively prevented from being soiled and clogged.
The scum S flowing into the pipe skimmer a passes through the pipe skimmer a and is discharged to the scum pit 3, and the scum S in the scum pit 3 is processed by a processing means such as a sludge processing machine (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.

Since the scum removing device having the above-described configuration can be moved to the opening 5 in a short time without causing the scum S to be flocked and accompanied by a fast water flow, the quality of the discharged treated water is prevented from deteriorating. In addition, the amount of water accompanying the discharge of the scum S can be reduced, and an excellent effect that energy saving can be achieved can be obtained. That is, the scum removing device having the above-described configuration has a property that can greatly contribute to so-called ecological measures.
In addition, since the openings 10 of the ejection nozzles 8, 8... Are closed by the closing member 11, it is possible to effectively prevent the inside of the nozzles from being contaminated and blocked by scum or the like contained in water.

The jet nozzle according to the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to the above-described embodiment, and design changes and the like can be made without departing from the gist of the present invention. Is possible.
For example, in the above-described example, the cross-sectional shape of the pipe material P is circular, but this can also be rectangular.
In the above example, the ejection nozzles 8, 8... Are applied to the final sedimentation basin of the sewage treatment facility, but the sedimentation basin may be the initial sedimentation basin or another sedimentation basin for factory wastewater. Furthermore, the present invention may be applied to an inflow trough (a water trough). Furthermore, the present invention can also be applied to a recovery tank that floats and collects 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.

1 ... Sedimentation basin (final sedimentation basin)
2 …… Supernatant water takeout part 3 …… Scum pit 4 …… Rotation drive mechanism 5 …… Opening part 6 …… Guide plate 7 …… Pressure water supply pipe 8 …… Ejection nozzle (ejection nozzle for scum removal device, scum removal device) Jet nozzle body)
9 ... Connecting pipe 10 ... Opening 11 ... Closing member 12 ... Support shaft a ... Pipe clearance P ... Pipe material S ... Scum

Claims (3)

An ejection nozzle for a scum removal device that ejects pressure water from the water toward an opening of a pipe skimmer of the scum removal device,
The scum removing device jet nozzle main body is provided with a closing member for closing the opening when pressure water is not ejected from the scum removing device jet nozzle main body. Spout nozzle. 2. The scum removing device ejection nozzle according to claim 1, wherein the closing member is made of a material that floats in water, and one end side of the closing member is pivotally supported so as to rotate from the scum removing device ejection nozzle body. An ejection nozzle for a scum removing device, wherein the opening is closed by buoyancy when no water is ejected. The ejection nozzle for a scum removing device according to claim 1 or 2 , wherein the scum removing device is provided in a sedimentation basin for sediment separation treatment after biological treatment of sewage.

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