Oil-water separation device

Abstract

To provide an oil / water separation device which has the increased recovery capacity of sludge-like substance, thereby being capable of maintaining an oil-water separation capacity over a long period time.SOLUTION: An oil / water separation device 10 comprises: an oil skimmer 12 which can perform first oil-water separation treatment on oil-water mixed liquid; and an oil-water separation tank 13 which can perform second oil-water separation treatment on the oil-water mixed liquid which is discharged from a discharge port 12a of the oil skimmer 12 and has undergone the first oil-water separation treatment. A supply passage 16 for supplying the oil-water mixed liquid after the first oil-water separation treatment to the oil-water separation tank 13 is provided between the discharge port 12a of the oil skimmer 12 and an opening 13a of the oil-water separation tank 13, and a cage-shaped body 17 with at least a bottom 17a composed of mesh structure is disposed on the supply passage 16.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an oil-water separation device.

Background Art

[0002] In various types of machining operations, oil (lubricating oil) is generally used to improve lubricity, for example by reducing cutting resistance. In addition, a cooling liquid called coolant is often used for cooling purposes. These lubricating oils and cooling liquids are recovered after the above machining, subjected to predetermined treatment, and then reused.

[0003] Water-soluble cutting oil, which is a mixture of water and oil, is often used as the cutting oil for coolant. Since it is diluted with water before use, it is excellent in safety aspects such as low risk of ignition, but on the other hand, it is prone to deterioration due to factors such as bacterial growth in the water. Therefore, when using a water-soluble cutting oil as a coolant, the necessity of separating oil components such as lubricating oil from the coolant increases.

[0004] As a separation means for this type of oil component, a device using an oil skimmer is generally used (for example, see Patent Document 1). In addition, a device using an oil-water separation tank that utilizes the specific gravity difference between oil and water has also been proposed (for example, see Patent Document 2).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] Incidentally, in actual manufacturing environments, coolant can sometimes contain not only lubricating oil but also sludge-like substances generated from processing scraps and other materials. Although this type of sludge-like substance is separated from the coolant in the coolant tank along with the oil by an oil skimmer, most of it is supplied to the oil-water separator along with the oil. The supplied sludge-like substance settles and enters the clean tank along with the water, so even if the oil is separated in the oil-water separator, it cannot become clean water. Furthermore, because the sludge-like substance floats and mixes with the oil, the difference in specific gravity between the oil and water fluctuates, which may prevent proper separation of oil and water in the oil-water separator.

[0007] For example, Patent Document 2 describes placing a debris-receiving net at the opening of an oil-water separator to collect large debris in wastewater. However, if this configuration is applied as is to collect sludge-like substances, the maximum bottom area of ​​the debris-receiving net, which is directly related to the sludge-like substance collection capacity, will be limited by the opening area of ​​the oil-water separator. This could result in insufficient sludge-like substance collection capacity, and consequently, a relatively rapid decline in oil-water separation capacity. Furthermore, if a net with the above configuration is placed at the opening of an oil-water separator, the oil and sludge-like substances in the separator will mix, causing fluctuations in the specific gravity difference between oil and water, which could reduce the oil-water separation capacity.

[0008] In view of the above circumstances, this specification aims to provide an oil-water separation apparatus that can maintain its oil-water separation capability over a long period of time by improving its ability to recover sludge-like substances. [Means for solving the problem]

[0009] The aforementioned problem is solved by the oil-water separation device according to the present invention. Specifically, this separation device comprises an oil skimmer capable of performing a first oil-water separation treatment on an oil-water mixture, and an oil-water separation tank capable of performing a second oil-water separation treatment on the oil-water mixture discharged from the outlet of the oil skimmer after the first oil-water separation treatment, wherein a supply passage is provided between the outlet of the oil skimmer and the opening of the oil-water separation tank for supplying the oil-water mixture after the first oil-water separation treatment to the oil-water separation tank, and a cage-like body having at least a mesh structure at its bottom is disposed on the supply passage.

[0010] As described above, in the oil-water separation apparatus according to the present invention, when a two-stage oil-water separation treatment is sequentially performed on an oil-water mixture using an oil skimmer and an oil-water separation tank, a supply passage is provided between the oil skimmer and the oil-water separation tank for supplying the oil-water mixture after the first oil-water separation treatment to the oil-water separation tank, and a mesh cage-like body is placed on this supply passage. With this configuration, the bottom area of ​​the cage-like body can be freely set without any special settings, compared to, for example, when the cage-like body for recovering sludge-like substances is installed at the opening of the oil-water separation tank, as in Patent Document 2. Therefore, by increasing the bottom area of ​​the cage-like body, it becomes possible to recover more sludge-like substances from the oil-water mixture. In addition, the larger the bottom area, the longer the period until sludge-like substances are recovered from the cage-like body, so it is possible to extend the maintenance cycle of the cage-like body. In other words, it is possible to maintain the excellent separation capacity of the oil-water separation apparatus as a whole over a long period of time.

[0011] Furthermore, in the oil-water separation apparatus according to the present invention, the supply passage may be inclined downward as it moves from the oil skimmer side towards the oil-water separation tank side.

[0012] In this way, by inclining the supply channel downwards, the cage-like bodies placed on the supply channel can be positioned in a downward-sloping orientation. Therefore, the bottom surface area of ​​the mesh-structured cage-like bodies can be increased, further improving the sludge recovery capacity and enabling the overall excellent separation capacity of the oil-water separator to be maintained for a longer period of time. [Effects of the Invention]

[0013] As described above, the present invention makes it possible to provide an oil-water separation device that can maintain its oil-water separation capability over a long period of time by increasing the ability to recover sludge-like substances. [Brief explanation of the drawing]

[0014] [Figure 1] This is a front view of an oil-water separator according to one embodiment of the present invention. [Figure 2] Figure 1 is a plan view of the oil-water separator shown in Figure 1. [Modes for carrying out the invention]

[0015] The contents of an oil-water separator according to one embodiment of the present invention will be described below with reference to the drawings. In this embodiment, the example described is when an oil-water mixture, in which lubricating oil as the oil component is mixed with sludge-like substances such as cutting chips in water-soluble cutting oil (water-soluble coolant) as the water component, is the target of oil-water separation.

[0016] Figure 1 shows a front view of the main parts of the oil-water separator 10 according to this embodiment. Figure 2 shows a plan view of the oil-water separator 10 shown in Figure 1. As shown in Figures 1 and 2, the oil-water separator 10 mainly comprises an oil skimmer 12 for performing a first oil-water separation treatment on the oil-water mixture stored in the coolant tank 11, an oil-water separation tank 13 for performing a second oil-water separation treatment on the oil-water mixture after the first oil-water separation treatment, a clean tank 14 to which the clean water obtained after treatment by the oil-water separation tank 13 is supplied, a waste oil tank 15, a supply passage 16 disposed between the oil skimmer 12 and the oil-water separation tank 13, and a cage-like body 17.

[0017] As described above, the coolant tank 11 stores an oil-water mixture in which lubricating oil and sludge-like substances are mixed with water-soluble coolant. Part of the oil skimmer 12 (in this case, the belt 18) is immersed in the oil-water mixture in the coolant tank 11, and the operation of the oil skimmer 12 allows mainly the oil and sludge-like substances in the oil-water mixture to be extracted upwards. In addition, at least the area of ​​the coolant tank 11 directly below the drain port 14a of the clean tank 14 is open upwards, and the clean water (water from which almost all oil and sludge-like substances have been removed) obtained as a result of two oil-water separation treatments discharged from the drain port 14a of the clean tank 14 is sent to the coolant tank 11.

[0018] Any type of oil skimmer can be used as the oil skimmer 12, and in this embodiment, an oil skimmer with a structure that adheres oil to the belt 18 and extracts it from the oil-water mixture is used. Therefore, in this embodiment, as shown in Figure 1, the oil skimmer 12 is arranged so that a part of the belt 18 is immersed in the oil-water mixture of the coolant tank 11.

[0019] The oil-water separation tank 13 is configured to separate the oil component from the water component in the oil-water mixture by utilizing the specific gravity difference between the oil component and the water component in the oil-water mixture, and an oil discharge port (oil drain port 13b) is provided on one circumferential side of the opening 13a of the oil-water separation tank 13. In this case, a waste oil tank 15 is disposed adjacent to one side portion (the left side portion as viewed in FIG. 2) of the oil-water separation tank 13, and the waste oil tank 15 opens upward below the oil drain port 13b. Thereby, the separated oil component discharged from the oil drain port 13b is delivered to the waste oil tank 15.

[0020] Further, a clean tank 14 is disposed adjacent to the other side portion (the right side portion as viewed in FIG. 2) of the oil-water separation tank 13. The oil-water separation tank 13 and the clean tank 14 are partitioned from each other by a partition wall 13c. On the other hand, the oil-water separation tank 13 and the clean tank 14 communicate with each other in a region below the partition wall 13c (not shown), so that the water component that has been vertically separated in the oil-water separation tank 13 can enter the clean tank 14 through the region below the partition wall 13c. Then, clean water is delivered to the coolant tank 11 via a drain port 14a provided on one side portion (the upper side portion as viewed in FIG. 2) of the clean tank 14.

[0021] The supply passage 16 is disposed between the discharge port 12a of the oil skimmer 12 and the opening 13a of the oil-water separation tank 13. In the present embodiment, the supply passage 16 is disposed such that the upstream end 16a of the supply passage 16 is located below the discharge port 12a, and the opening 13a of the oil-water separation tank 13 is located below the downstream end 16b of the supply passage 16 (see FIG. 1). In the present embodiment, the supply passage 16 is disposed so as to incline downward from the oil skimmer 12 side toward the oil-water separation tank 13 side.

[0022] The basket-shaped body 17 is disposed on the supply passage 16 and below the discharge port 12a of the oil skimmer 12. In the present embodiment, as shown in FIG. 1, the basket-shaped body 17 is disposed on the supply passage 16 in a state of being lifted from the bottom surface 16c of the supply passage 16.

[0023] The widthwise dimension W1 of the downstream end portion 16b of the supply passage 16 is necessarily restricted by the widthwise dimension of the opening 13a of the oil-water separation tank 13, but at least on the upstream side of the supply passage 16, there is no particular restriction on the widthwise dimension. Therefore, the widthwise dimension W2 of the cage-shaped body 17 is set to be larger than the widthwise dimension W1 of the downstream end portion 16b of the supply passage 16.

[0024] Further, in the present embodiment, the cage-shaped body 17 is configured such that one circumferential side portion (the upstream side portion) is open. Thereby, for example, sludge adhering to the bottom portion 17a and the downstream side portion 17b of the cage-shaped body 17 can be easily discharged from the side of the opening 17c.

[0025] At least the bottom portion 17a of the cage-shaped body 17 has a mesh structure. In the present embodiment, the entire cage-shaped body 17 has a mesh structure. Note that the mesh coarseness of the cage-shaped body 17 is in principle arbitrary, and is preferably set to an appropriate size in consideration of the size of the sludge-like substance to be captured.

[0026] The oil-water separation tank 13, the clean tank 14, and the waste oil tank 15 are provided on a common base 19, and in the present embodiment, both widthwise sides of the base 19 and the floor surface 20 are connected by leveling bolts 21. By adjusting the posture of the base 19 with the leveling bolts 21 on both sides, the balance between the oil level height of the oil-water separation tank 13 and the water level height of the clean tank 14 can be adjusted.

[0027] Hereinafter, an example of the oil-water separation treatment in the present embodiment will be described.

[0028] First, the oil skimmer 12 is driven to perform a first oil-water separation treatment on the oil-water mixture in the coolant tank 11. In the present embodiment, by rotationally driving the belt 18 of the oil skimmer 12 immersed in the oil-water mixture, oil content and sludge-like substances are caused to adhere to the surface of the belt 18 and lifted upward. Then, a blade portion (not shown) disposed close to the surface of the belt 18 removes the oil content and sludge-like substances adhering to the surface of the belt 18 from the belt 18, and the removed substances are discharged together with the remaining water from the discharge port 12a.

[0029] The oil-water mixture after the first oil-water separation treatment, discharged from the outlet 12a, is sent to a cage-like body 17 located below the outlet 12a. Here, the bottom 17a of the cage-like body 17 has a mesh structure, so the sludge-like substance contained in the oil-water mixture after the first oil-water separation treatment is captured by the bottom 17a of the cage-like body 17 and separated from the oil and water. Furthermore, if these sludge-like substances, oil, and water flow together on the bottom 17a, the downstream side 17b of the cage-like body 17, located at the downstream end, also has a mesh structure, so the sludge-like substance is captured by this side 17b and separated from the oil and water.

[0030] Here, the supply channel 16 located below the cage-like body 17 is inclined downwards as it approaches the oil-water separator tank 13. As a result, the oil and water separated from the sludge-like substance by the mesh structure of the cage-like body 17 fall below the cage-like body 17, flow along the supply channel 16 towards the oil-water separator tank 13, and are supplied to the opening 13a of the oil-water separator tank 13.

[0031] The oil and water supplied to the oil-water separator tank 13 undergo a second oil-water separation treatment by the oil-water separator tank 13. Here, the difference in specific gravity between oil and water is used to separate the oil-water mixture into oil and water. As a result, an oil layer is formed at the top of the oil-water separator tank 13, and the area below the oil layer is entirely water. The oil separated at the top of the oil-water separator tank 13 is sent to the adjacent waste oil tank 15 through the oil outlet 13b. Meanwhile, the water separated from the oil is sent to the clean tank 14, which is connected to the oil-water separator tank 13 below the partition wall 13c. The clean water separated from the oil is then sent to the coolant tank 11 through the drain outlet 14a provided in the clean tank 14. In this way, a two-stage oil-water separation treatment and sludge separation treatment are performed on the oil-water mixture.

[0032] As described above, in the oil-water separator 10 according to this embodiment, when a two-stage oil-water separation treatment is sequentially performed on an oil-water mixture using an oil skimmer 12 and an oil-water separator tank 13, a supply passage 16 is provided between the oil skimmer 12 and the oil-water separator tank 13 for supplying the oil-water mixture after the first oil-water separation treatment to the oil-water separator tank 13, and a mesh-structured cage-like body 17 is placed on this supply passage 16. With this configuration, the bottom area of ​​the cage-like body 17 can be freely set without any particular restrictions. Therefore, by setting the width dimension W2 of the cage-like body 17 to be larger than the width dimension W1 of the downstream end 16b of the supply passage 16, the bottom area of ​​the cage-like body 17 can be increased, making it possible to recover more sludge-like substances from the oil-water mixture. In addition, the larger the bottom area, the longer the period until sludge-like substances are recovered from the cage-like body 17, making it possible to extend the maintenance cycle of the cage-like body 17. In other words, it becomes possible to maintain the excellent separation capability of the oil-water separator 10 as a whole over a long period of time.

[0033] Furthermore, in this embodiment, the supply passage 16 is arranged to slope downwards from the oil skimmer 12 side towards the oil-water separator tank 13 side. By arranging the supply passage 16 in this way, the cage-like body placed on the supply passage 16 can be positioned in a downward-sloping position. Therefore, the bottom area of ​​the mesh-structured cage-like body 17 can be made larger, which further improves the ability to recover sludge-like substances and allows the excellent separation ability of the oil-water separator 10 as a whole to be maintained for a longer period of time.

[0034] Although one embodiment of the present invention has been described above, the oil-water separator according to the present invention may also adopt configurations other than those described above, without departing from the spirit of the invention.

[0035] For example, in the above embodiment, the bottom 17a of the cage-like body 17 is made flat across its entire surface, but this is not the only option. The bottom 17a may be curved in a concave or convex shape as a whole. Alternatively, it may take any shape other than flat, such as by providing minute irregularities, as long as it does not hinder the transport of oil and moisture downstream.

[0036] Furthermore, in the above embodiment, the cage-like body 17 was positioned slightly above the supply passage 16 (see Figure 1), but the arrangement of the cage-like body 17 is not limited to this. For example, the cage-like body 17 may be placed on the bottom surface 16c of the supply passage 16, as long as the oil and water are transported smoothly.

[0037] Furthermore, in the above embodiment, the supply path 16 is given a straight line shape, but of course, it is not limited to this. If a shape with a bend is preferable due to the installation space, etc., the supply path 16 can take any shape as long as it does not hinder the transport of oil and water. [Explanation of symbols]

[0038] 10 Oil / water separator 11 Coolant tank 12 Oil Skimmers 12a Outlet 13 Oil-water separation tank 13a opening 13b Oil drain port 13c Partition wall 14 Clean Tank 14a Drain 15 Waste oil tank 16 Supply route 16a Upstream end 16b Downstream end 16c bottom 17 Cage-like structures 17a bottom 17b Side 17c opening 18 belts 19 Base 20 Floor surface 21 Leveling bolts

Claims

1. An oil skimmer capable of performing a first oil-water separation treatment on an oil-water mixture, An oil-water separation apparatus comprising an oil-water separation tank capable of performing a second oil-water separation treatment on the oil-water mixture after the first oil-water separation treatment discharged from the outlet of the oil skimmer, Having sides and a bottom, extending horizontally from directly below the discharge port of the oil skimmer to directly above the opening of the oil-water separator tank, a supply passage is provided for supplying the oil-water mixture after the first oil-water separation treatment to the oil-water separator tank. Upstream of the downstream end of the supply channel, there is a portion that is wider in the width direction than the downstream end. An oil-water separator comprising a cage-like body having at least a mesh structure at its bottom, disposed on the portion of the supply channel that has a large width dimension.

2. An oil skimmer capable of performing a first oil-water separation treatment on an oil-water mixture, An oil-water separation apparatus comprising an oil-water separation tank capable of performing a second oil-water separation treatment on the oil-water mixture after the first oil-water separation treatment discharged from the outlet of the oil skimmer, Between the discharge port of the oil skimmer and the opening of the oil-water separator tank, a supply passage is provided for supplying the oil-water mixture after the first oil-water separation treatment to the oil-water separator tank. A cage-like body having at least a mesh structure at its bottom is provided on the supply path. The supply path is inclined downwards from the oil skimmer side towards the oil-water separator tank side. An oil-water separator in which the cage-like body is arranged on the downwardly inclined supply path, and an opening is provided on the side of the cage-like body on the upstream side of the supply path.

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