Patent ID: 12186761

DESCRIPTION OF EMBODIMENTS

Before explaining a specific structure of a spout nozzle N (hereinafter, it is called “spout nozzle”) for a scum removal device according to one embodiment of the present invention, a water conduit1provided with the spout nozzle N is explained usingFIG.1toFIG.3.

The water conduit1is configured including a water conduit main body2and a scum pit3in a state of being connected to the water conduit main body2. The water conduit main body2presents a top-open type long water path and configured so that raw water consists of sewage is supplied (refer to the arrow “a”) from one end side of its longitudinal direction (the right end side in the illustrated example).

The scum pit3is provided at a final end side (the left end side in the illustrated example) in a flow direction of the raw water of the water conduit main body2; a part of a wall surface forming the scum pit3and a wall surface forming the final end side of the water conduit main body2are shared. A height of an upper wall surface3aof the shared wall surface is determined to be a bit lower than a water surface in the water conduit main body2(refer toFIG.2). On a side at the water conduit main body2of the wall surface where the upper wall surface3ais provided, a movable gate4is provided to be configured so that the raw water can be controlled to flow into the scum pit3from the water conduit main body2.

The movable gate4is composed by including a gate plate4aand a drive device4bwhich is omitted inFIG.1and composed so as to be closed as shown inFIG.2when scum S is not discharged from the water conduit main body2into the scum pit3, and be open as shown inFIG.3when the scum S is discharged in the scum pit3from the water conduit main body2. Accordingly, when the movable gate3is open as shown inFIG.3, the surface water of the water conduit main body2, i.e., the raw water including the scum S can be discharged into the scum pit3.

A width of the gate plate4ais a bit smaller than a channel width of the water conduit main body2; and its height is determined to be sufficiently larger than a difference between a position of the upper wall surface3aand a water surface position in the water conduit main body2. The drive device4bis composed to move the gate plate4aup and down: a known up/down movement device such as a system formed from a screw rod and a rotary nut, a rack and pinion system, or the like is applied.

When the scum S is not discharged, as shown inFIG.2, the drive device4blifts the gate plate4aso that an upper end position of the gate plate4ais sufficiently higher than the water surface position in the water conduit main body2to shut between the scum pit3and the water conduit main body2. When the scum S is discharged, as shown inFIG.3, the drive device4bbrings the gate plate4adown so that the upper end position of the gate plate4ais lower than the water surface position in the water conduit main body2and also a bit lower than a bottom surface position of the scum S generated in this water conduit main body2, so that the scum pit3and the water conduit main body2can be communicated with each other.

Outside one side wall5of a longitudinal direction of a long water path forming the water conduit main body2, a plurality of sedimentation basin6which are primary sedimentation basins in the sewage-treatment plant are parallelly provided.

A part of the side walls of the sedimentation basins6are composed of the side walls5of the water conduit main body2. A flow inlet7with an open/close door (not shown) is provided at substantially an intermediate height position of the side walls5. Therefore, the interior of the water conduit main body2and the interior of the sedimentation basins6are composed to be communicated to each other through this flow inlet7. Accordingly, when the open/close door of the flow inlet7is open, the raw water in the water conduit main body2flows into the sedimentation basins6, and the raw water which flowed-in can flow in the sedimentation basins6toward the direction departing from the side walls5(refer to the arrow “b” inFIG.1). In addition, although the sedimentation basins6are disposed alongside outside the one side wall5of the water conduit main body2in the illustration example, these may be disposed alongside outside both side walls5.

In the water conduit main body2, a plurality of water jet nozzles8composed by including a water supply pipe8aand a nozzle8bare provided. The plurality of the water jet nozzles8are provided at a bit higher than the water surface in the water conduit main body2and to partition the length of the flow direction of the water in the water conduit main body2at a prescribed interval.

The water supply pipes8aare provided between the side walls5of the water conduit main body2facing to each other to be perpendicular to a longitudinal direction of the water conduit main body2. To the water supply pipes8a, water is supplied with a prescribe pressure through a pump which is not shown. The processed water of the sewage-treatment plant can be used for the water supplied to the water supply pipes8a.

The nozzles8bare provided with keeping a prescribed interval in a longitudinal direction of the water supply pipes8aso that a tip-end opening is downward at a lower section of the water flow in the water conduit main body2. Therefore, when the pressure water is supplied to the water supply pipes8a, spout water is supplied to the layered scum S generated on the surface layer of the water conduit main body2from the nozzles8bto help the flow of the scum S about to flow toward the scum pit3(refer toFIG.3). Note that, in the present invention, the scum S grown up to have some degree of thickness on the water surface may be sometimes called as a “scum layer S” for convenience of explanation.

On this water conduit main body2, the spout nozzles (the spout nozzle for a scum removal device of the present invention) N are provided. The plurality of the spout nozzles N are provided in water a bit lower than the water surface in the water conduit main body2with a prescribed interval in the flowing direction of the water in the water conduit main body2. The plurality (four in the example shown inFIG.1) of the spout nozzles N are also provided keeping a prescribed interval with each other along a direction perpendicular to a flow direction of the water in the water conduit main body2, i.e., in a channel width.

The spout nozzles N are disposed in water being supported by pressure water supply pipes which are not illustrate. When the pressure water is supplied to the spout nozzles N from the pressure water supply pipes, the spout nozzles N spout the pressure water from the openings facing toward the scum pit3side and can help the flow of the scum S about to flow toward the scum pit3(refer toFIG.3). the processed water of the sewage-treatment plant can be used for the water supplied to the spout nozzles N.

Air spout devices9are provided on the water conduit main body2. The air spout devices9are formed from a pipe and horizontally provided along flow direction in the water conduit main body2inside both side walls5of the water conduit main body2by supporting devices which are not illustrated (refer toFIG.1toFIG.3). The air spout devices9are provided to be below the scum layer S generated in the water conduit main body2. For instance, in a case in which to discharge the scum S from the water conduit main body2into the scum pit3if the scum S stays and grows to near 10 cm in its thickness by the operation of the water conduit1, the air spout device9is located a bit lower than 10 cm from the water surface. The location position of the air spout devices9is different according to the sewage-treatment plant where the water conduit main body2is installed; anyway, it is decided to be below the generated scum S.

Since the present applicant has already suggested this air spout devices9in Japanese Patent Application No. 2020-152897, detailed explanation is omitted: one configured by forming a large number of slits on a pipe made of elastomer such as natural rubber, synthetic rubber or the like with an interval in a length direction, one configured by forming a large number of holes on a pipe made of steel with an interval in a length direction, or the like can be adopted. One can also applicable which can prevent clogging by providing the holes of the steel pipe downward and attaching blow-out members in a cup-shape, a bowl-shape, or the like on each hole having an opening opens downward. By the air spout devices9, when the compressed air is supplied into the pipe, it is emitted as air bubbles in the raw water from the slits or the holes. The emitted air bubbles rise along the inner surface of the side walls5and can peel the scum layer S off adhered to the side walls5.

Next, the spout nozzle N will be explained withFIG.4toFIG.8.

A nozzle body10is provided with an inlet-side housing part11made of synthetic resin such as polycarbonate into which the pressure water is supplied, and a tip-end-side nozzle part12communicated with the inlet-side housing part11and formed into a flat cylindrical shape having a width larger than a height. Disposing the flat tip-end-side nozzle part12in the water conduit main body2toward the downstream side in the flow direction, it is considered not to be a resistance of the water flow as possible.

A planar shape of the nozzle body10is formed to have a broader width at the tip end side than at the base end side (at the right side than at the left side inFIG.6) as shown inFIG.4toFIG.6. The tip-end-side nozzle part12is formed to have a width dimension gradually larger toward the tip end. The tip end of the tip-end-side nozzle part12is formed as shown inFIG.7andFIG.8, to be inclined at an angle about 20° regarding the inflow direction of the pressure water in the inlet-side housing part11so as to be a bit upward in the water.

The inside of the nozzle body10is formed as one space as shown inFIG.7andFIG.8; the space is separated into a pressure water chamber13in the inlet-side housing part11and a valve body storing chamber14in the tip-end-side nozzle part12. The pressure water chamber13has a large volume; the valve body storing chamber14has a flat shape in which a width is larger than a height and is formed to be larger in the width toward the tip end.

On an end surface at the broader width side of the tip-end-side nozzle part12in the nozzle body10, an opening15is provided to open the valve body storing chamber14to the exterior. The opening15extends over the entire end surface at the broader width side, and the shape of the opening15shows a slit shape. The nozzle body10is provided so that the longitudinal direction of the opening15is parallel to the water surface in the water conduit main body2and also perpendicular to both side surfaces5when it is installed on the water conduit main body2shown in above-describedFIG.1toFIG.3.

On the base end part of the inlet-side housing part11, an installing part16is integrally provided (refer toFIG.4toFIG.6). The installing part16shows a pipe shape having thread groove around itself and an interior space of the installing part16is communicated with the pressure water chamber13as shown inFIG.7andFIG.8. The installing part16is formed to be able to screw with a screw hole formed in a pressure water supply pipe which is not illustrated by a screw groove.

The valve body storing chamber14stores a valve body20inside. The valve body20is provided with a valve main body part21, a hinge shaft22, a closing part23, and sinkers24. The valve main body part21, the hinge shaft22, and the closing part23are formed integrally of synthetic resin such as polycarbonate similarly to the nozzle main body10.

The valve main body part21is formed in a plate shape having a size which can move up and down in the valve body storing chamber14of the tip-end-side nozzle part12; a plate thickness thereof is formed to be smaller than a thickness of the valve body storing chamber14, e.g., a thickness equal to or smaller than the thickness of the valve body storing chamber14. The width of the valve main body part21is formed so as to be gradually increased toward the tip end suitably to the valve body storing chamber14in the tip-end-side nozzle part12.

On both sides of the base end part of the valve main body part21, the hinge shafts22and22are horizontally provided to project to both sides. These hinge shafts22and22are rotatably held in the vicinity of the center part of the nozzle main body10, at both sides near an upper wall12aat the base end part of the tip-end side nozzle part12. Thereby, the valve main body21can swing between a position which is in contact with a lower surface of the upper wall12aof the tip-end-side nozzle part12and a position which is in contact with the upper surface of a lower wall12bof the tip-end-side nozzle part12so that the tip end part makes vertical motions in the opening15of the tip-end-side nozzle part12.

In this case, since the hinge shafts22and22are held around the upper wall12aof the tip-end-side nozzle part12, when the tip end part is in contact with the upper wall12aof the tip-end-side nozzle part12, as shown inFIG.7, the upper surface of the valve main body part21is entirely in contact with the lower surface of the upper wall12aof the tip-end-side nozzle part12. Accordingly, a space having substantially even thickness is formed between the lower surface of the valve main body part21and the upper surface of the lower wall12bof the tip-end-side nozzle part12. This space is a space formed below the valve main body part21, and configures a discharging path (a lower space)17communicated with the pressure water chamber13. Since the valve body storing chamber14is formed to have the width gradually increasing toward the tip end, this discharge path17is also formed to have a width gradually increasing toward the tip end.

In a state in which the entire upper surface of the valve main body part21is in contact with the lower surface of the upper wall12aof the tip-end-side nozzle part12as shown inFIG.7, the tip end of the discharge path17is open between the lower surface of the valve main body part21and the upper surface of the lower wall12bof the tip-end-side nozzle part12, and a discharging opening (the lower opening of the present invention)17ais formed. A channel cross-sectional area of the discharging opening17ais formed to be a smaller cross-sectional area than a maximum channel cross-sectional area of the pressure water chamber13.

FIG.7is a state in which the valve main body part21is disposed in the upper part of the valve body storing chamber14, so that the valve body storing chamber14and the opening15are respectively small since the valve main body part21occupies there and form the discharge path17and the discharging opening17a; therefore, the discharge path17and the discharging opening17aare denoted in parentheses.

The closing part23projects outward (in a discharging direction of the pressure water) from the valve body storing chamber14of the tip-end-side nozzle part12and is formed in a state in which the tip end part of the valve main body part21is bended upward. The closing part23is formed over the entire width of the valve main body part21, and a height thereof is formed to be larger than a height of the valve body storing chamber14. When the valve main body part21is in contact with the upper surface of the lower wall12bof the tip-end-side nozzle part12(when the discharging opening17ais closed), the closing part23is located in the vicinity of a front of an opening (hereinafter, it is called as an upper side opening)18aof an upper space18formed between the upper surface of the valve main body21and the lower surface of the upper wall12aof the tip-end-side nozzle part12. Accordingly, a state in which the closing part23closes the upper opening18acan be made. The upper opening18ais an opening formed between the upper surface of the valve main body21and the lower surface of the upper wall12aof the tip-end-side nozzle part12by locating the valve main body part21among the opening15of the valve body storing chamber15to be in contact with the upper surface of the lower wall12bof the tip-end-side nozzle part12.

The sinkers24are made of disk-shaped stainless steel or the like, and provided two on the upper surface of the valve main body21with maintaining a prescribed interval via screws25. On the lower surface of the upper wall12aof the tip-end-side nozzle part12, a depressed part26is formed, so that it is planned that the sinkers24can be retracted in the depressed part26on the upper wall12awhen the valve main body part21is in contact with the upper wall12aof the tip-end-side nozzle part12(refer toFIG.7).

Accordingly, even though the sinkers24are provided to project from the upper surface of the valve main body part21, the sinkers24are disposed inside the depressed part26when the valve body20moves upward, so it is possible to maintain a sufficient opening area of the discharging opening17a. The weight of the sinkers24is decided in a range in which the valve main body part21is rotated in a counter-clockwise direction inFIG.7around the hinge shaft22when the pressure water is supplied to the nozzle main body10; or a range in which it can rotate in a clockwise direction ifFIG.7by the weight of the valve main body part21including the sinkers24when the supply of the pressure water is stopped.

The valve body20composed of the above-described structure is rotated upward around the hinge shafts22and22by the water pressure as shown inFIG.7when the pressure water is supplied to the spout nozzle N from the pressure water supply pipe which is not illustrated. Accordingly, the discharge path17and the discharging opening17acan be opened communicating with the pressure water chamber13between the valve body20and the lower wall12bof the tip-end-side nozzle part12.

When the pressure water is not supplied to the spout nozzle N, as shown inFIG.8, the valve main body part21is rotated downward around the hinge shafts22and22by its own weight. Accordingly, the valve main body part21is brought into contact with the lower wall12bof the tip-end-side nozzle part12to close the discharging opening17a; meanwhile, the upper opening18aformed above the valve main body21is closed by the closing part23. Therefore, the opening15of the tip-end-side nozzle part12is entirely closed.

Although the valve body20of the above structure is provided with two sinkers24formed of stainless steel or the like having a disk shape so as to increase the weight of the valve main body part21, the sinker can be one rectangular strip. In a case in which the valve body20itself has a sufficient weight, for example, in a case in which the valve main body part21and the closing part23are formed of stainless steel or the like, the sinkers24can be omitted. However, when the parts of the nozzle main body10except for the sinkers24and the screws25are made of synthetic resin, it is preferable to provide the sinker24to make sure to move the valve main body21.

Moreover, the spout nozzle N having the above-described structure can be easily made of synthetic resin. In this case, the part of the upper wall12aof the tip-end-side nozzle part12with which the valve body20is assembled is open, and the open part is closed after the valve body20is assembled within the tip-end-side nozzle part12.

Spout operation of the pressure water of the spout nozzle N having the above-described structure will be explained. When the pressure water is supplied to the pressure water chamber13through the installing part16, the supplied pressure water is once stored in the pressure water chamber13. Then, the pressure water in the pressure water chamber13is supplied to the valve body storing chamber14having a channel cross-sectional area smaller than that of the pressure water chamber13.

In the valve body storing chamber14in the tip-end-side nozzle part12, since the base end of the valve body20is held on the upper wall12aof the tip-end-side nozzle part12, in the base end part of the valve main body21, the lower surface thereof is separated from the lower wall12bof the tip-end-side nozzle part12. Therefore, the pressure water flows to the tip end direction while pressing the lower surface of the valve main body part21to push up the tip end of the valve main body part21and bring it into contact with the lower surface of the upper wall12aof the tip-end-side nozzle part12.

Accordingly, the discharge path (lower space)17is formed between the lower surface of the valve main body part21and the upper surface of the lower wall12bof the tip-end-side nozzle part12; and the pressure water flows through the discharge part17and is discharged from the discharging opening (lower opening)17a. Since the discharging opening17ais formed to have a smaller cross-sectional area than the maximum channel cross-sectional area of the pressure water chamber13, the pressure water is spouted with great force. The discharge path17has a flat shape gradually spread out toward the discharging opening17a; the pressure water is discharged to spread in the horizontal direction.

The direction (refer to the arrow “d” inFIG.7) of the water flow of the pressure water discharged from the discharging opening17ais slightly upward with respect to the direction (refer to the arrow “c” inFIG.7) of the water flow of the pressure water supplied from the pressure water chamber13through the installing part16in accordance with the inclination of the tip-end-side nozzle part12. Generally, when the spout nozzle N is provided at the water conduit1, the pressure water chamber13of the nozzle main body10is provided so as to be maintained to be horizontal; so that the water flow slightly upward (at an angle about 20° to the horizontal) with respect to the horizontal is discharged from the discharging opening17aof the tip-end-side nozzle part12.

Next, the operation of removing scum in the water conduit1provided with the spout nozzle N composed of the above-described structure will be explained.

The raw water (sewage) is supplied in the water conduit main body2and the supplied raw water is divided and supplied through the flow inlets7provided for the respective sedimentation basins6, so that the scum S is gradually generated on the water surface. In this condition, since the pressure water is not supplied to the spout nozzle N, the valve body20of the valve body storing chamber14is in contact with the lower wall12bof the tip-end-side nozzle part12and the upper opening18aformed above the valve body20is closed by the closing part23. Accordingly, it is prevented that the water flows in the upper side and the lower side of the valve main body part21from exterior, so that inconvenience in which the inside the nozzle body10is stained by the scum and the like contained in the water can be effectively prevented.FIG.2andFIG.8show this condition.

At the point when the generation of the scum S advances to a certain degree so that the thickness thereof achieves about 10 cm, the pressure water is supplied to the spout nozzle N. The pressure water is also supplied to the water jet nozzles8; and the compressed air is supplied to the air spout devices9. Accordingly, the operation of discharging the scum S to the scum pit3starts.

By supplying the pressure water to the spout nozzle N, the valve main body part21is rotated around the hinge shafts22and22by the water pressure by this supply of the pressure water. Accordingly, the closing part23moves upward and can open the discharging opening17a. From the open discharging opening17a, the pressure water is spouted so that the scum S flow to the scum pit3side. The spouting direction of the pressure water from the discharging opening17aact to slightly lift up the scum S since the inclination of the tip-end-side nozzle part12of the nozzle body10is formed slightly upward, and the movement of the scum S is performed smoothly.

At the same time, the pressure water is spouted out also from the water jet nozzles8so as to flow the scum S to the scum pit3side. Furthermore, since the scum S adhered on the side wall5is removed by the air spouted from the air spout devices9, the scum S is discharged to the scum pit3more smoothly and quickly.FIG.3andFIG.7shows this condition.

When most of the scum S is discharged from the water conduit main body2, the supply of the pressure water to the spout nozzle N, and the water jet nozzles8is stopped, and the supply of the compressed air to the air spout device9is stopped. Accordingly, the discharging operation of the scum S to the scum pit3is terminated.

For the discharging operation of the above-described scum S to the scum pit3, the water jet nozzles8and the air spout devices9were both used; however, either one may be used. It is decided whether both are used or either one is used according to characteristic and the like of the generated scum S.

The operation starting or stopping the discharge of the above-described scum S to the scum pit3can be automatically carried out; however, since the scum S is not evenly generated according to water quality and the like of the raw water flowing in the water conduit main body2, it is decided by experiments. That is, it is desirable to observe the discharging condition of the scum S by manually operating for a first few days of driving the equipment to decide. Then, the automatic operation is carried out according to the observation result. However, the automatic operation is not limited to the above-described example; it may be carried out according to detection signals by detecting the thickness of the scum S generated in the water conduit main body2by a sensor.

The spout nozzle according to the present invention was explained above referring drawings; however, the specific structure is not limited to the above embodiment example, but the design and the like can be modified without departing from the summary of the present invention.

For example, in the above example, the spout nozzle N was applied on the water conduit1in the sewage treatment plant; however, it may be applied on a first sedimentation basin or a final sedimentation basin in the sewage treatment plant or a sedimentation basin for industrial waste water. In this case, without stirring the water in the sedimentation basin uselessly, to help the flow which can move the surface layer water where the scum S floats to a scum discharging device side such as a pipe skimmer, the power of the water spouted from the discharging opening17ais adjusted. That is, the pressure of the pressure water supplied to the spout nozzle N is adjusted and the power of the water spouted from the discharging opening17ais adjusted.

The spout nozzle N according to the present invention can be applied for a recovery tank for recovering valuables by floatation separation. In a case of this recovery tank, the scum S of the present invention corresponds to the valuables. Moreover, there is a case in which the fluid is not water. Accordingly, the “scum” of the present invention contains such valuables, and the “water” contains such liquid.

INDUSTRIAL APPLICABILITY

It can be appropriately used for a scum removal device located on a final sedimentation basin and the like in the sewage treatment plant.

REFERENCE SIGNS LIST

1Water conduit2Water conduit main body3Scum pit4Movable gate5Side wall6Sedimentation basin7Flow inlet8Water jet nozzle9Air spout deviceS ScumN Spout nozzle for scum removal device (Spout nozzle)10Nozzle body11Inlet-side housing part12Tip-end-side nozzle part12aUpper wall12bLower wall13Pressure water chamber14Valve body storing chamber15Opening16Installing part17Discharge path (Lower space)17aDischarging opening (Lower opening)18Upper space18aUpper opening20Valve body21Valve main body part22Hinge shaft23Closing part24Sinker25Screw26Depressed part