JP7287159B2 - Oil film remover - Google Patents

Description

TECHNICAL FIELD The present invention relates to an oil film removing device capable of recovering an oil film floating on the water surface of waste water.

In factories, water such as cleaning water and cooling water is used in the operation of various machine tools and their production equipment, and oils such as various processing oils and lubricating oils are used, and water and oil are mixed during the operation. wastewater is generated. Since such wastewater can also cause water pollution, it must be treated to meet prescribed environmental standards, such as removing sludge such as oil films floating on the wastewater and mixed sludge, before being discharged outside the factory. or reused. As a device for detecting such an oil film in waste water, for example, a waste water oil film detection device disclosed in Patent Document 1 is known. This drain oil film detection device is provided with a pair of guide plates across the water surface of the measurement chamber, and detects the oil film between the guide plates.

International Publication 2010/058513

However, although the device of Patent Document 1 can detect the oil film contained in the wastewater, no special consideration is given to the removal of the oil film, and the oil film cannot be removed efficiently. In particular, after the oil film is detected, the waste water flows down from the measurement chamber to the outflow chamber, which agitates the oil film on the water surface, making it difficult to remove the oil film.

That is, an object of the present invention is to provide an oil film removing apparatus capable of efficiently removing an oil film from waste water.

In order to overcome the above problems and achieve the intended purpose, the first means is
An oil film removing device for removing an oil film from wastewater in which water and oil are mixed,
an inflow tank into which waste water flows from the inflow pipe;
a first flow path forming wall connected to a wall surface forming the inflow tank and provided so that the wall surface faces the inflow position side of the waste water to the inflow tank;
A communication channel, which is connected to a wall surface forming the inflow tank and opposed to a wall surface to which the first flow path forming wall is connected, and through which waste water from the inflow tank can flow, is formed with the first flow path forming wall. a second flow path forming wall formed between
a recovery tank provided on the outflow side of the communication channel and into which waste water can flow from the inflow tank through the communication channel;
A collection pump is provided so as to float on the water surface of the collection tank and collects the oil film on the water surface.
Thus, by guiding the wastewater from the inflow tank to the recovery tank through the communication channel formed by the first and second channel forming walls, the oil film of the wastewater can be efficiently removed. . At this time, by directing the wall surface of the channel forming wall toward the inflow position of the wastewater into the inflow tank, the waviness of the water surface caused by the inflow of the wastewater into the inflow tank is generated in the channel between the channel forming walls. It can be difficult to enter. As a result, the oil film can be recovered while the water surface is gently undulating, and the oil film recovery efficiency can be enhanced.

A second means is
The recovery tank is provided with a partition wall surrounding the outlet of the communication channel, and the inner region of the partition wall connecting the water surface to the outlet of the communication channel and the partition wall separating the water surface from the communication channel. and the recovery pump is arranged in the inner region surrounded by the partition wall, and
The gist is that the inner region and the outer region of the partition wall are connected under water.
In this way, the outlet of the communication channel is surrounded by the partition wall, and the flow channel provided under the water surface connects the inner region and the outer region surrounded by the partition wall to allow the water to flow. By doing so, it is possible to ensure the flow of waste water while preventing the oil film from flowing out to the outside of the partition wall.

A third means is
The partition walls include a pair of first partition walls extending downstream from the wall surfaces of the first flow path formation wall and the second flow path formation wall facing the recovery tank, and the pair of first flow path formation walls. and a second partition wall connecting the partition walls.
Thus, by surrounding the outflow port of the communication channel with the first and second partition walls, it is possible to reliably prevent the outflow of the oil film.

A fourth means is
The gist is that the first flow path forming wall is provided with a door member for opening and closing the inflow port at an end portion of the communication flow path on the side of the inflow port.
By providing the door member in this way, it is possible to make it difficult for waving of the water surface due to the inflow of waste water into the inflow tank to enter the communication channel between the channel forming walls.

A fifth means is
The door member is configured such that a gap is formed between the door member and the second flow path forming wall in a state in which the opening/closing tip of the door member is closest to the second flow path forming wall. This is the gist.
In this way, in a state in which the open/close tip of the door member is closest to the flow path forming wall, a gap is created between the flow path forming wall and the oil film floating on the water surface of the waste water. It is possible to allow the oil to flow from the tank to the recovery tank, thereby preventing the oil film from remaining in the inflow tank.

A sixth means is
The gist of the invention is that an oil film detection device detects an oil film on the water surface of the communication channel.
In this way, by detecting the oil film on the connecting flow path between the flow path forming walls into which waviness of the water surface due to the inflow of waste water into the inflow tank is difficult to enter, the detection accuracy of the oil film can be improved.

A seventh means is
A gist is that a shielding wall is provided so as to be positioned between an inflow position where waste water flows into the inflow tank and an inflow port of the communication channel.
In this way, by providing the shielding wall, it is possible to more efficiently suppress the waving of the water surface due to the inflow of wastewater into the inflow tank from entering the communication channel between the channel forming walls. It becomes possible to collect the oil film in a state where the waviness is gentle.

According to the present invention, it is possible to efficiently remove an oil film from waste water.

1 is a plan view showing a schematic configuration of an oil film removing device according to an embodiment of the present invention; FIG. FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1; (a) is an enlarged view of the B section in FIG. 1, and (b) is a perspective view of the B section.

BEST MODE FOR CARRYING OUT THE INVENTION Next, the oil film removing apparatus according to the present invention will be described below with reference to preferred embodiments with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, in the oil film removing apparatus 10 of the present embodiment, a treatment tank 12 for removing oil film from wastewater is divided into an inflow tank 14 and a recovery tank 30. It is configured to remove the oil film of the waste water led from the inflow tank 14 to the collection tank 30 via the flow path connecting with the collection tank 30 . Specifically, as shown in FIG. 1, the oil film removing apparatus 10 has flow path forming walls 18 and 20 provided alternately from opposing wall surfaces 12a and 12b to separate an inflow tank 14 and a recovery tank 30. The tank 12 is partitioned, and a recovery pump (oil film recovery means) 50 is provided so as to float on the water surface L of the recovery tank 30, and a drainage pump (drainage Means) 52 is provided downstream from the recovery pump 50 . The flow path forming walls 18 and 20 are configured to form a flow path 22 between which the drainage can flow. Waste water flows from the inflow tank 14 to the recovery tank 30 through the flow path 22 , and the oil film on the water surface L of the waste water flowing into the recovery tank 30 is removed by the recovery pump 50 . The inflow tank 14 and the recovery tank 30 are connected by a channel 22 so that the water surface level is positioned at substantially the same height. The discharge port 16a of the inflow pipe 16 is positioned above the water surface L of the inflow tank 14, so that waste water discharged from factories or the like is discharged into the inflow tank 14. The discharge port 16 a of the inflow pipe 16 may be positioned below the water surface of the inflow tank 14 .

The flow path forming walls 18 and 20 are, as shown in FIG. 18, and a second wall surface 12b extending from the second wall surface 12b toward the first wall surface 12a at a position spaced apart from the discharge port 16a (inflow position of waste water) of the inflow pipe 16 than the first flow path forming wall 18. and a channel forming wall 20 . Here, the extending end (side end) of the first flow path forming wall 18 is located closer to the second wall surface 12b than the extending end (side end) of the second flow path forming wall 20 is. In addition, the extending end (side end) of the second flow path forming wall 20 is positioned closer to the first wall surface 12 a than the extending end (side end) of the first flow path forming wall 18 . Then, the wall surface of the first flow path forming wall 18 and the wall surface of the second flow path forming wall 20 are configured to face each other with a constant gap therebetween. That is, the first flow path forming wall 18 and the second flow path forming wall 20 extend alternately from the opposing wall surfaces (first wall surface 12a and second wall surface 12b) of the inflow tank 14 (processing tank 12). A drainage channel 22 is thereby formed between the first channel forming wall 18 and the second channel forming wall 20 . In the following, for convenience of explanation, the drainage channel formed between the first channel-forming wall 18 and the second channel-forming wall 20 may be referred to as a communication channel 22 for distinction. be. Here, the first flow path forming wall 18 and the second flow path forming wall 20 are provided so that the wall surface faces the discharge port 16a (inflow position of the waste water) side of the inflow pipe 16, and the inflow tank 14 The rippling of the water surface L caused by the inflow of waste water into the connecting channel 22 is prevented from entering directly.

Here, as shown in FIG. 2, the first flow path forming wall 18 and the second flow path forming wall 20 extend above and below the water surface so as to dam the water surface L of the waste water. , the bottom end of the inflow tank 14 (processing tank 12) is spaced apart from the bottom surface thereof. That is, the inflow tank 14 and the recovery tank 30 are connected by the communication flow path 22, and the flow under the water surface formed below the first flow path forming wall 18 and the second flow path forming wall 20. While ensuring the flow rate of wastewater flowing from the inflow tank 14 to the recovery tank 30 by the channel under the water surface, the oil film on the water surface is guided to the recovery tank 30 via the communication channel 22. be. In this way, the first flow path forming wall 18 and the second flow path forming wall 20 are formed to cross at least the water surface L of the waste water stored in the treatment tank 12 (inflow tank 14), and float on the water surface. The oil film is guided to the recovery tank 30 through the communication channel 22 .

In addition, the inflow tank 14 is provided with a shielding wall 24 between the discharge port 16 a of the inflow pipe 16 (inflow position of the waste water) and the inflow port of the connecting channel 22 . The shielding wall 24 is connected to the bottom surface of the inflow tank 14 (treatment tank 12) with the wall surface facing the discharge port 16a (inflow position of waste water) of the inflow pipe 16, and is formed so that the upper end protrudes from the water surface L. , rippling of the water surface L caused by the inflow of waste water into the inflow tank 14 is suppressed so that the rippling of the water surface L does not enter the communication channel 22 . Both side ends of the shielding wall 24 are separated from the first wall surface 12a and the second wall surface 12b. Each of them secures a drainage channel.

A partition wall 32 surrounding the outlet of the communication channel 22 is provided in the recovery tank 30 . Specifically, the partition wall 32 is connected to the wall surface of the first flow path forming wall 18 on the first wall surface 12a side from the extending end (side end) of the second flow path forming wall 20. A first partition wall (first partition wall) 32a extending inside the recovery tank 30 and an extending end portion of the first flow path forming wall 18 with respect to the wall surface of the second flow path forming wall 20 A second partition wall (first partition wall) 32b extending from the (side end) to the second wall surface 12b side to the inside of the collection tank 30, and the first partition wall 32a and the second partition wall 32b. The third partition wall (second partition wall) 32c connected to the extension end surrounds the outlet of the communication channel 22. As shown in FIG. The configuration of the partition wall 32 is not limited to such a configuration. It can be formed in an arbitrary form such as an arc-shaped wall whose end continues to the wall surface of the formation wall 20 .

The partition wall 32 extends above and below the water surface so as to block the water surface L of the recovery tank 30, and is provided so that the lower end is separated from the bottom surface of the recovery tank 30 (processing tank 12). . In other words, in the collection tank 30 , an inner region 34 and an outer region 36 surrounded by the partition wall 32 are connected by an underwater channel formed below the partition wall 32 . Further, the drainage pump 52 is provided in the collection tank 30 so that the suction port is located in the outer region 36 of the partition wall 32 . This enables the flow of waste water from the inflow tank 14 to the recovery tank 30 through the communication channel 22, and partitions the oil film on the water surface of the waste water led to the recovery tank 30 through the communication channel 22. The submerged channel allows the flow of wastewater from the inner region 34 to the outer region 36 while confined to the inner region 34 enclosed by the wall 32 .

The recovery pump 50 is arranged in the inner area 34 surrounded by the partition wall 32 to remove the oil film remaining on the water surface in the inner area 34 . This recovery pump 50 is a float-type recovery pump 50 in which a submersible pump connected to a drain pipe is floated by a plurality of (three in the figure) floats. As such a recovery pump 50, for example, a device disclosed in Japanese Unexamined Patent Application Publication No. 2000-24656 can be cited.

In addition, the oil film removing device 10 of this embodiment is provided with an oil film detection device 54 that detects an oil film floating on the water surface L of the communication channel 22. During the process in which waste water flows through the communication channel 22, the recovery tank 30 It is designed to detect an oil film flowing to the As the oil film detection device 54, conventionally known various devices such as a reflected light method, a polarization ratio analysis method, and a fluorescence method can be employed. Here, the reflected light method utilizes the fact that the reflection intensity of light such as light emitting diode light or laser light irradiated onto the water surface L is greater in oil than in water. The oil film on the water surface is detected using the increase as an index. In addition, the polarization ratio analysis method is based on the fact that when the reflected light of light such as light emitting diode light or laser light irradiated onto the water surface L is polarized and separated, the polarization ratio is greater in oil than in water. It uses the increased polarization ratio as an index to detect the oil film on the water surface. The fluorescence method utilizes the fact that oil has the property of generating fluorescence. The fluorescence spectrum is measured when the water surface L is irradiated with excitation light of a specific wavelength, and the increase in fluorescence intensity is used as an index. It detects the oil film. In this embodiment, a fluorescent method is used for the support plate 38 that spans over the upper ends of the first flow path forming wall 18 and the second flow path forming wall 20 so as to be positioned above the communication flow path 22. An oil film detection device 54 is arranged, and the water surface L of the communication channel 22 is irradiated with ultraviolet rays of 300 to 400 nm from the oil film detection device 54. When fluorescence of 400 to 500 nm is measured, the communication channel It is configured to determine that there is an oil film on the water surface L of 22 . It should be noted that the wavelength of the excitation light emitted from the oil film detection device 54 and the fluorescence spectrum for determining the oil film are examples and can be changed as appropriate. When the oil film detection device 54 detects the oil film, the recovery pump 50 operates to remove the oil film, and when the oil film detection device 54 fails to detect the oil film, the recovery pump 50 stops operating. It's becoming

A first door member 41 for opening and closing the inlet of the connecting flow path 22 is provided at the extending end of the first flow path forming wall 18, and the extension of the second flow path forming wall 20 is provided. A second door member 42 for opening and closing the outlet of the communication channel 22 is provided at the end, and the inlet and outlet of the communication channel 22 are separated by the first door member 41 and the second door member 42 . The opening width of is made variable. Here, since the first door member 41 and the second door member 42 are basically configured to be openable and closable with the same structure, the first door member 41 will be described, and the second door member 42 will be described with the same structure. , and description thereof is omitted.

As shown in FIG. 3, the first door member 41 is rotatably supported by a hinge member 44 provided at the extending end of the first flow path forming wall 18, and is rotated by an angle adjusting member 46. is held in a state in which the angle of rotation with respect to the passage forming wall 18 is changed. Here, the angle adjustment member 46 is a rod-shaped member whose one end is rotatably supported by the support plate 38, and which penetrates vertically at a plurality of locations (five locations in the embodiment) spaced apart in the longitudinal direction. A hole 46a is provided. Then, the fixing pin 48 inserted from above into the through hole 46a of the angle adjusting member 46 is inserted into a hole (not shown) formed in the upper end surface of the first door member 41, thereby inserting the fixing pin 48. The first door member 41 is held at an angle corresponding to the position of the through hole 46a.

In this embodiment, the first door member 41 extends along the first flow path forming wall 18 in an open position (indicated by a solid line in FIG. 3(a)), and the first flow path forming wall 18 The first door member 41 can be held at a plurality of angular positions between the first door member 41 and the closed position (illustrated by the two-dot chain line in FIG. 3(b)). Here, in a state where the opening/closing tip of the first door member 41 is closest to the second flow path forming wall 20 (closed position), the first door member 41 and the second flow path forming wall 20 are closed. It is configured such that a gap S is provided between them. That is, even when the first door member 41 is in the closed position, the oil film of the waste water can flow into the communication channel 22 from the inflow tank 14 . Similarly, an open position in which the second door member 42 extends along the second flow path forming wall 20 and a closed position in which the second door member 42 is perpendicular to the second flow path forming wall 20. The opening/closing tip of the second door member 42 is closest to the first flow path forming wall 18 (closed position). A gap S is formed between the second door member 42 and the first flow passage forming wall 18 . That is, even when the second door member 42 is in the closed position, the oil film of the waste water flows into the recovery tank 30 from the communication channel 22 .

As described above, in the oil film removing apparatus 10 according to the embodiment, the waste water flowing into the inflow tank 14 from the drain pipe is channeled through the connection formed between the first flow path forming wall 18 and the second flow path forming wall 20 . By guiding the waste water to the recovery tank 30 through the channel 22, the oil film can be recovered in a state where the influence of waviness due to the inflow of the waste water is small, and the oil film of the waste water can be efficiently removed. In particular, by arranging the wall surfaces of the first flow path forming wall 18 and the second flow path forming wall 20 toward the side of the inflow position of the waste water into the inflow tank 14, the waste water flowing into the inflow tank 14 It is possible to make it difficult for the waving of the water surface L to enter the channel between the channel forming walls. Therefore, the oil film can be recovered while the water surface L is gently undulating, and the oil film recovery efficiency can be enhanced.

Furthermore, since the shielding wall 24 is provided so as to be positioned between the inflow position where the wastewater flows into the inflow tank 14 and the inflow port of the communication channel 22, the water surface L is not affected when the wastewater flows into the inflow tank 14. Waving can be more efficiently suppressed from entering the communication channel 22, and the oil film can be collected in a state where the waving of the water surface L is mild. The oil film detection device 54 detects the oil film on the communication channel 22 between the channel forming walls 18 and 20, into which waviness of the water surface L caused by the inflow of waste water into the inflow tank 14 is difficult to enter. Detection accuracy can be improved.

In addition, the outlet of the communication channel 22 is surrounded by the partition wall 32, and the recovery pump 50 is arranged in the inner region 34 of the partition wall 32. The oil film flowing into the partition wall 32 can be prevented from flowing out to the outside of the partition wall 32, and the oil film concentrated in the inner region 34 surrounded by the partition wall 32 can be efficiently recovered by the recovery pump 50.例文帳に追加At this time, since water is allowed to flow downstream from the inner region 34 surrounded by the partition wall 32 under the water surface, the flow of wastewater flowing into the inner region 34 of the partition wall 32 via the communication channel 22. can be ensured. That is, it is possible to secure the flow of wastewater while preventing the outflow of the oil film, and efficiently collect the oil film of the wastewater in the inner region 34 of the partition wall 32 . The outflow port of the communication channel 22 includes a first partition wall 32a connected to the wall surface of the first flow channel forming wall 18, a second partition wall 32b connected to the wall surface of the second flow channel forming wall 20, and the Outflow of the oil film can be reliably prevented only by enclosing with a simple structure consisting of the first partition wall 32a and the third partition wall 32c connected to the extended end portions of the second partition wall 32b.

In addition, by providing a first door member 41 at the extended end of the first flow path forming wall 18 so as to open and close the inlet of the communication flow path 22, the inflow of waste water into the inflow tank 14 can be prevented. The degree of opening of the inlet of the communication channel 22 can be adjusted according to the accompanying waving of the water surface L, and entry of the waving of the water surface L into the communication channel 22 can be efficiently suppressed. That is, the inflow port of the communication flow path 22 can be opened to a degree corresponding to the waving of the water surface L which fluctuates according to the inflow amount of the waste water into the inflow tank 14 . In this manner, by suppressing the waving of the water surface L to the communication channel 22 by the first door member 41, the oil film detection by the oil film detection device 54 can be performed more accurately. Then, in a state in which the opening/closing tip of the first door member 41 is closest to the first flow path forming wall 18 (a state in which the first door member 41 is closed), the first door member 41 and the first flow path are closed. By providing a gap S between the forming wall 18 and the oil film, the oil film floating on the water surface L of the waste water can flow from the inflow tank 14 to the communication channel 22 (recovery tank 30). It is possible to prevent stagnation in the inflow tank 14 .

Further, a second door member 42 is provided at the extended end of the second channel forming wall 20 so that the outlet of the communication channel 22 can be opened and closed, thereby preventing the inflow of wastewater into the inflow tank 14. The degree of opening of the outflow port of the communication channel 22 can be adjusted according to the accompanying waving of the water surface L, and entry of the waving of the water surface L into the recovery tank 30 can be efficiently suppressed. That is, the outlet of the communication channel 22 can be opened to a degree that matches the waving of the water surface L that fluctuates depending on the amount of waste water flowing into the inflow tank 14 . In addition, even in an environment where waviness of the water surface L is likely to occur on the side of the recovery tank 30 (the inner region 34 of the partition wall 32), such as when the oil film removing device 10 is installed outdoors, the water surface L of the recovery tank 30 is The degree of opening of the outflow port of the communication channel 22 can be adjusted according to the undulation, and the entry of the undulation of the water surface L of the recovery tank 30 into the communication channel 22 can be efficiently suppressed. In this manner, by suppressing the waving of the water surface L to the communication channel 22 by the second door member 42, the oil film detection by the oil film detection device 54 can be performed more accurately. Then, in a state in which the opening/closing tip of the second door member 42 is closest to the second flow path forming wall 20 (a state in which the first door member 41 is closed), the second door member 42 and the second flow path are closed. By leaving a gap S between the formation wall 20 and the oil film floating on the water surface L of the waste water, the oil film can flow from the communication channel 22 to the recovery tank 30, and the oil film can flow into the communication channel 22. It can prevent staying. In addition, by adjusting the degree of opening of the outflow port of the communication channel 22 by the second door member 42 according to the amount of oil film remaining in the recovery tank 30, backflow of the oil film from the recovery tank 30 to the communication channel 22 is suppressed. Therefore, the oil film detection by the oil film detection device 54 can be performed more accurately.

(Change example)
The configuration is not limited to the configuration of the above-described embodiment, and can be modified, for example, as follows.
(1) In the embodiment, the lower end of each flow path forming wall is separated from the bottom surface of the inflow tank (treatment tank). You may make it provide so that it may continue. Even with such a configuration, it is possible to guide waste water from the inflow tank to the recovery tank through the flow path formed between the flow path forming walls. Alternatively, an opening may be formed in the channel forming wall so as to be positioned below the surface of the water to form a channel through which waste water flows from the inflow tank to the recovery tank under the water surface.
(2) In the embodiment, the lower end of the partition wall is separated from the bottom surface of the recovery tank (treatment tank). Alternatively, a flow path may be formed to allow the water to flow downstream from the inner region 34 surrounded by the partition wall below the surface of the water.
(3) In the embodiment, a part of the collection tank (the outlet of the communication channel) is surrounded by the partition wall, but the partition wall may be omitted.
(4) In the embodiment, an inflow tank and a recovery tank are provided, but a water tank may be provided downstream of the recovery tank for performing water quality improvement treatment on waste water from which the oil film has been removed.

10 oil film removing device, 12a first wall surface (wall surface forming inflow tank)
12b Second wall surface (wall surface facing the wall surface where the first flow path forming wall continues)
14 inflow tank, 16 inflow pipe, 18 first flow path forming wall, 20 second flow path forming wall 24 shielding wall, 30 recovery tank, 32 partition wall 32a first partition wall (first partition wall), 32b Second partition wall (first partition wall)
32c third partition wall (second partition wall), 34 inner region, 36 outer region 41 first door member (door member), 50 recovery pump, 54 oil film detector, S gap

Claims (6)

An oil film removing device for removing an oil film from wastewater in which water and oil are mixed,
an inflow tank into which waste water flows from the inflow pipe;
a first flow path forming wall connected to a wall surface forming the inflow tank and provided so that the wall surface faces the inflow position side of the waste water to the inflow tank;
A communication channel, which is connected to a wall surface forming the inflow tank and opposed to a wall surface to which the first flow path forming wall is connected, and through which waste water from the inflow tank can flow, is formed with the first flow path forming wall. a second flow path forming wall formed between
a recovery tank provided on the outflow side of the communication channel and into which waste water can flow from the inflow tank through the communication channel;
a recovery pump that is provided to float on the water surface of the recovery tank and recovers the oil film on the water surface ;
The first flow path forming wall is provided with a door member for opening and closing the inflow port at the end of the communication flow path on the side of the inflow port.
An oil film removing device characterized by: The recovery tank is provided with a partition wall surrounding the outlet of the communication channel, and the inner region of the partition wall connecting the water surface to the outlet of the communication channel and the partition wall separating the water surface from the communication channel. and the recovery pump is arranged in the inner region surrounded by the partition wall, and
2. The oil film removing device according to claim 1, wherein the inner area and the outer area of the partition wall are connected under water. The partition walls include a pair of first partition walls extending downstream from the wall surfaces of the first flow path formation wall and the second flow path formation wall facing the recovery tank, and the pair of first flow path formation walls. 3. The oil film removing device according to claim 2, further comprising a second partition wall connecting said partition walls. 3. The door member is configured such that a gap is formed between the door member and the second flow path forming wall when the open/close tip of the door member is closest to the second flow path forming wall. 4. The oil film removing device according to any one of 1 to 3 . The oil film removing device according to any one of claims 1 to 4 , wherein an oil film detection device detects the oil film on the water surface of the communication channel. The oil film removing device according to any one of claims 1 to 5 , further comprising a shielding wall positioned between an inflow position where waste water flows into the inflow tank and an inflow port of the communication channel.

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