JP4038365B2

JP4038365B2 - Oil / water separator

Info

Publication number: JP4038365B2
Application number: JP2001353957A
Authority: JP
Inventors: 公男齋藤; 聰塚原; 憲治仲川
Original assignee: Hitachi Industrial Equipment Systems Co Ltd
Current assignee: Hitachi Industrial Equipment Systems Co Ltd
Priority date: 2001-11-20
Filing date: 2001-11-20
Publication date: 2008-01-23
Anticipated expiration: 2021-11-20
Also published as: JP2003154205A

Description

【０００１】
【発明の属する技術分野】
本発明は油と水の混合された液体から油と水を分離するための油水分離装置に関し、特に、微細気泡による浮上分離法を用いた油水分離装置に関するものである。
【０００２】
【従来の技術】
気泡の浮上作用による油水分離の従来技術として特開平５−３１７８４７号公報がある。特開平５−３１７８４７号公報にには、先ず、圧力ポンプに連結した吸液管先端に設けたフロート弁、及び供給管の先端の圧力弁を被処理部内に付け、加圧ポンプにより被処理部から被処理液を汲み上げ、この被処理液を加圧状態でコンプレッサーからの圧縮空気と共に気液混合手段に供給することにより、液中に空気が混合、溶解される。この加圧液を加圧タンクから供給管を経て先端の圧力弁から被処理部内へ供給することで、加圧液中の微細気泡が被処理部中を膨張しながら浮上すると共に油粒子に付着して、これを浮上させることで油水分離を行えると説明されている。
【０００３】
【発明が解決しようとする課題】
上記特開平５−３１７８４７号公報に示された従来技術において、気液混合手段出口までに加圧液中に溶解できなかった空気は処理槽内で大気泡となり、油浮上分離性能を低下させるので加圧タンクで分離し、エアアウトサイレンサから外部に開放している。しかし、加圧タンクの内部では気泡が油粒子を浮上させ気液面に浮上油を発生させる油水分離を起こし、浮上油がタンク内部の気液面に存在する状態となる。この浮上油は処理液中の油分濃度が低下した後、気液面の波動によって処理液中に少量ずつ混じる。従って、処理液を直接排水可能な油分濃度まで下げるための処理時間が非常に長い。更に、加圧タンク中は加圧下であるため余剰空気の気泡径が小さくなり、浮上速度が遅くなる。このため余剰空気を分離するためには加圧タンクが大きくなるという問題があった。
【０００４】
そこで、本発明の目的は余剰空気の分離性能が高く、その際の浮上油の滞留を防止した油水分離装置を提供することにある。
【０００５】
【課題を解決するための手段】
上記目的を達成するために本発明は、空気を混合した加圧状態の被処理液をノズルで減圧することにより生成した大気泡を分離する大気泡分離部を設け、分離した大気泡を処理槽内上部に供給する大気泡排出管を設け、微細気泡を含む被処理液を処理槽に設けた分離部下部に連続的に供給する構成とした。
【０００６】
【発明の実施の形態】
図１に本発明による油水分離装置の機器構成図の第一の実施形態を示す。
図１において、処理槽３の内部には、被処理水を分離する分離部と浮上油受け器６とを分離する遮蔽板２が設けてある。この遮蔽板２は、被処理液面よりわずかに高くなるように配置してある。処理槽３には、不溶解空気除去するための大気泡除去部１に設けたノズル５より供給された空気が混合された被処理液の主流が分離部３ａに流出するように、大気泡除去部１の開口部が分離部３ａに接続されている。更に、処理槽３の分離部３ａには、２つの液面検出器７、８が設けてある。一方の液面検出器（以後、第１の液面検出器７と称す）は被処理液面の最大位置を検出する位置に、他方の液面検出器（以後、第２の液面検出器８と称す）は被処理液面が大気泡除去部１の開口部上端より下にならない位置に配置してある。また、大気泡除去部１の出口近傍の上側には、空気が混合された被処理液の分岐流を流すための大気泡排出管９が取り付けてある。この大気泡排出管９は、処理槽３の高さ方向の中間部から分離部内に挿入され、その端部が被処理液面近傍になる位置に配置してある。なお、大気泡除去部の天井側（上側）は大気泡排出管９に気泡が集まりやすいように、配出管の口に向かって傾斜を設けると良い。また、大気泡除去部１の出口側の天井部に突起、又はじゃま板を設けることで、大気泡が分離部３ａ側に流出しにくくすることで、大気泡の除去性能を向上させることもできる。なお、ここでは被処理液と分離された油分を多く含む部分（浮上油）とを区別して説明する。
【０００７】
ノズル５には加圧供給配管２４が接続され、この加圧供給配管２４にはポンプ４が接続されている。処理槽３の下部には、循環配管２５が接続され、循環調節弁１５を介して、被処理液空気供給配管２３に導かれポンプ４に接続している。循環配管２５の途中で分岐した排出配管２６には排出調節弁１６が接続され、処理後の液は排出調節弁１６より排出される。循環配管２５が取り付けられた被処理液空気供給配管２３には被処理液供給配管２１と空気導入配管２２が接続されている。被処理液供給配管２１には被処理液供給を制御する被処理液調節弁１４が、空気導入配管２２には空気の流量を制御する空気流量調節弁１７が接続されている。更に、浮上油受け器６には、浮上油排出管２９が接続されており、浮上油Ｃを排出できるように構成されている。
【０００８】
次に本装置の動作について説明する。
被処理液供給運転時は、循環調節弁１５と排出調節弁１６を閉じ、被処理液調節弁１４を開放した状態でポンプ４を稼動する。被処理液は被処理液供給配管２１からポンプ４を通り、加圧供給配管２４と、ノズル５と、大気泡除去器１を経て、処理槽３の分離部３ａへ流入し、予め設定した液面高さまで供給する。本実施形態では、この液面高さの検出は第１の液面検出器７で行うようにしているが、ポンプ４の液量検出器を用いたり、ポンプ４の流量と時間の関係などで代用することもできる。分離部３ａへ供給された被処理液の液面が予め設定した高さまで達すると、被処理液中の油粒子を微細気泡により浮上分離する処理運転を行う。
【０００９】
処理運転時には、まず循環調節弁１５を開放し、被処理液調節弁１４を閉め、分離部３ａの被処理液をポンプ４を介して循環させる。この時、被処理液空気供給配管２３内が被処理液の流れのために負圧になる。この特性を利用して空気導入配管２２より空気を被処理液空気供給配管２３内に導く。供給空気量は空気流量調節弁１７で調節する。供給空気はポンプ４が高速で回転しているために細かい気泡となって被処理液と混合し、溶解し易くなる。ポンプ４の吐出側に断面積の小さなノズル５を設けたことにより、加圧供給配管２４内部は高圧となり、被処理液中に溶解する空気量が多くなる。この溶解空気量は、液量と圧力に比例する。本実施形態では空気導入配管２２、空気流量調節弁１７をポンプ４の吸引側に配置しているが、ポンプ４の吐出側に空気導入配管´２２、空気流量調節弁´１７として配置しても良い。この際には、加圧供給配管２４内部が高圧となっているため、加圧供給配管２４内圧力よりも高い圧力で空気を供給する必要がある。
【００１０】
空気導入配管２２より供給された空気の余剰分は、溶解せず気泡のまま高圧の被処理液中に残る。ポンプ４出口の圧力は、所要動力を少なくするためと、減圧後に発生する微細気泡の直径を小さくすることを考慮すると０．３〜０．８ＭＰａ程度が良い。ノズル５から噴射された溶解した空気を伴う被処理液と溶解しない空気は大気泡除去部１に送られる。ここで、溶解した空気は高圧から大気に開放されるため、微細気泡Ｂとして発生し、溶解しない空気は高圧から大気開放された分だけ気泡が大きくなって余剰気泡Ａとなる。直径の大きい余剰気泡Ａは液中上昇速度が大きく、大気泡除去部１の途中の管上部に集まる。先に述べたように、大気泡除去部１の出口近傍の上側には処理槽３内被処理液面近傍に連通している大気泡排出管９を設けており、余剰気泡Ａはこの大気泡排出管９から排出される。
【００１１】
この際に浮上分離した油分は処理槽３の分離部３ａへ同時に送られる。そして分離部３ａ内には被処理液と微細気泡Ｂが送られることになる。分離部３ａに送られた微細気泡Ｂは、上昇し被処理液中の油粒子と結びつき、油粒子は分離部３ａ上部の液面上に浮上油Ｃとして溜まり、被処理液を油分と水に分離する。この溜まった浮上油Ｃは、遮断板２の高さを超えた場合に、浮上油受け器６に流れ出て、浮上油排出管２９より排出される。また、これを超えない場合には液面上に浮上油Ｃとして溜まる。このため、浮上油Ｃを掻き取る装置等を用いなくても、浮上油Ｃの処理が可能である。処理槽３内の被処理液は循環配管２５を介して、ポンプ４に戻される。この処理運転は、被処理液が予め設定した油分濃度（例えば油分濃度５ｍｇ／Ｌ以下）となる時間まで行われる。
【００１２】
被処理液の油分濃度が所定の値となる時間だけ処理運転すると、次に排水運転を行う。排水運転は、排出調節弁１６を開放し、予め設定した液面まで、排出する。本実施形態では、この時の液面検出を第２の液面検出器８を用いて行っているが、液面と排出時間の関係などを代用することもできる。この排出運転後、被処理液供給運転に戻り、全体は回分式の運転となる。
【００１３】
以上、第一実施形態によれば、回分式にて従来の常圧下で微細気泡と余剰空気を効率よく分離でき油水分離性能を高くすることができる。
【００１４】
図２は、本発明による油水分離装置の第二の実施形態を示す機器構成図である。図２において、図１に示したものと同一物、相当品には同一符号を付けている。
【００１５】
本発明の第二の実施形態が第一の実施形態と異なる点は、排出調整弁１６の排出口側に受けタンク１１と受けタンク配管２７とフィルタ１２とフィルタ配管２８とを設けたものである。運転の方法は前述の第一実施形態と略同じであるが、フィルタ１２を設けることで、処理運転の時間を短縮したものである。すなわち、処理運転時の処理槽３内の被処理液油分濃度と時間の関係は、実験よりＬｎＣ＝ＬｎＣ_０−ＫＴ（Ｃ：Ｔ時間後の被処理液油分濃度、Ｃ_０：初期被処理液油分濃度、Ｋ：定数、Ｔ：時間）として表わせることが明らかになった。このため、ある程度低い濃度（例えば２０〜３０ｍｇ／Ｌ程度）となってから、予め設定した油分濃度（例えば油分濃度５ｍｇ／Ｌ以下）となるまではかなりの時間が必要である。
【００１６】
そこで、予め設定する処理運転時間を第一実施形態よりも短かくし、低油分濃度となった処理運転後の処理液を受けタンク１１を介し、フィルタ１２でろ過処理をすることで、処理時間を低減できる。この際、フィルタ１２で分離する処理液の単位流量当たりの油分は少ないので、フィルタ寿命は従来から用いられているフィルタ単独処理方式よりも大幅に長くなる。また、受けタンク１１は、フィルタ１２へ供給する液量を調整することができるため、フィルタの小型化が可能である。
【００１７】
以上のように、本実施形態でも、従来に比べ分離性能を向上出来る他、第１の実施形態に比べて処理時間の短縮を図ることができる。
【００１８】
【発明の効果】
以上説明したように、本発明によれば、常圧下で微細気泡と余剰空気を効率よく分離でき、油水分離性能の高い油水分離装置を得ることができる。
【図面の簡単な説明】
【図１】本発明による油水分離装置の第一の実施形態を示す機器構成図である。
【図２】本発明による油水分離装置の第二の実施形態を示す機器構成図である。
【符号の説明】
１…大気泡除去部、２…遮断板、３…処理槽、３ａ…分離部、４…ポンプ、５…ノズル、６…浮上油受け器、７，８…液面検出器、９…大気泡排出管、１１…受けタンク、１２…フィルタ、１４…被処理液調節弁、１５…循環調節弁、１６…排出調節弁、１７、′１７…空気流量調節弁、２１…被処理液供給配管、２２，´２２…空気導入配管、２３…被処理液空気供給配管、２４…加圧供給配管、２５…循環配管、２６…排出配管、２７…受けタンク配管、２８…フィルタ配管、２９…浮上油排出管。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an oil / water separator for separating oil and water from a mixed liquid of oil and water, and more particularly to an oil / water separator using a floating separation method using fine bubbles.
[0002]
[Prior art]
Japanese Laid-Open Patent Publication No. 5-317847 discloses a conventional technique for oil-water separation by the floating action of bubbles. In JP-A-5-317847, first, a float valve provided at the tip of a liquid suction pipe connected to a pressure pump and a pressure valve at the tip of a supply pipe are attached to the part to be treated. The liquid to be treated is pumped up and supplied to the gas-liquid mixing means together with the compressed air from the compressor in a pressurized state, whereby the air is mixed and dissolved in the liquid. By supplying this pressurized liquid from the pressurized tank through the supply pipe to the treated part from the pressure valve at the tip, fine bubbles in the pressurized liquid float while expanding in the treated part and adhere to the oil particles. And it is explained that oil-water separation can be performed by floating this.
[0003]
[Problems to be solved by the invention]
In the prior art disclosed in the above Japanese Patent Laid-Open No. 5-317847, air that could not be dissolved in the pressurized liquid until the gas-liquid mixing means outlet becomes large bubbles in the treatment tank, which reduces the oil floating separation performance. Separated by a pressurized tank and opened to the outside from the air-out silencer. However, inside the pressurized tank, bubbles cause oil particles to float and cause oil / water separation to generate floating oil on the gas-liquid surface, so that the floating oil exists on the gas-liquid surface inside the tank. After the oil concentration in the processing liquid is lowered, the floating oil is mixed in the processing liquid little by little by the wave motion of the gas-liquid surface. Accordingly, the treatment time for reducing the treatment liquid to an oil concentration that can be directly drained is very long. Further, since the pressurized tank is under pressure, the bubble diameter of the surplus air is reduced and the ascent rate is reduced. For this reason, in order to isolate | separate excess air, there existed a problem that a pressurized tank became large.
[0004]
Accordingly, an object of the present invention is to provide an oil-water separator that has high separation performance of surplus air and prevents retention of floating oil at that time.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a large bubble separation unit for separating large bubbles generated by depressurizing a liquid to be treated in which air is mixed with a nozzle, and the separated large bubbles are treated in the treatment tank. A large bubble discharge pipe to be supplied to the inner upper part is provided, and a liquid to be processed containing fine bubbles is continuously supplied to the lower part of the separation part provided in the treatment tank.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a first embodiment of a device configuration diagram of an oil-water separator according to the present invention.
In FIG. 1, a shielding plate 2 that separates a separation unit that separates water to be treated and a floating oil receiver 6 is provided inside the treatment tank 3. The shielding plate 2 is arranged to be slightly higher than the liquid surface to be processed. In the treatment tank 3, large bubbles are removed so that the main flow of the liquid to be treated mixed with the air supplied from the nozzle 5 provided in the large bubble removal unit 1 for removing insoluble air flows out to the separation unit 3a. The opening of the part 1 is connected to the separation part 3a. Furthermore, two liquid level detectors 7 and 8 are provided in the separation unit 3 a of the processing tank 3. One liquid level detector (hereinafter referred to as the first liquid level detector 7) is located at the position for detecting the maximum position of the liquid level to be processed, and the other liquid level detector (hereinafter referred to as the second liquid level detector). 8) is disposed at a position where the liquid surface to be treated does not fall below the upper end of the opening of the large bubble removing unit 1. A large bubble discharge pipe 9 for flowing a branch flow of the liquid to be treated mixed with air is attached to the upper side in the vicinity of the outlet of the large bubble removing unit 1. The large bubble discharge pipe 9 is inserted into the separation part from the intermediate part in the height direction of the treatment tank 3 and is arranged at a position where the end part is near the liquid surface to be treated. The ceiling side (upper side) of the large bubble removing unit is preferably provided with an inclination toward the outlet of the distribution tube so that the bubbles are easily collected in the large bubble discharge tube 9. Further, by providing a projection or baffle on the exit side ceiling portion of the large bubble removing unit 1, it is possible to improve the large bubble removing performance by making it difficult for large bubbles to flow out to the separating unit 3a side. . Here, the liquid to be treated and the portion (floating oil) containing a large amount of separated oil will be described separately.
[0007]
A pressure supply pipe 24 is connected to the nozzle 5, and a pump 4 is connected to the pressure supply pipe 24. A circulation pipe 25 is connected to the lower part of the treatment tank 3, and is led to the liquid liquid supply pipe 23 to be treated via the circulation control valve 15 and connected to the pump 4. A discharge control valve 16 is connected to a discharge pipe 26 branched in the middle of the circulation pipe 25, and the treated liquid is discharged from the discharge control valve 16. A treated liquid supply pipe 21 and an air introduction pipe 22 are connected to the treated liquid air supply pipe 23 to which the circulation pipe 25 is attached. A treated liquid control valve 14 for controlling the treated liquid supply is connected to the treated liquid supply pipe 21, and an air flow rate regulating valve 17 for controlling the air flow rate is connected to the air introduction pipe 22. Further, a floating oil discharge pipe 29 is connected to the floating oil receiver 6 so that the floating oil C can be discharged.
[0008]
Next, the operation of this apparatus will be described.
During the liquid supply operation, the pump 4 is operated with the circulation control valve 15 and the discharge control valve 16 closed and the liquid control valve 14 opened. The liquid to be processed passes through the pump 4 from the liquid supply pipe 21 to be processed, passes through the pressure supply pipe 24, the nozzle 5, and the large bubble remover 1, and flows into the separation unit 3 a of the processing tank 3. Supply to surface height. In this embodiment, the detection of the liquid level is performed by the first liquid level detector 7, but the liquid level detector of the pump 4 is used or the relationship between the flow rate of the pump 4 and time is used. It can be substituted. When the liquid level of the liquid to be processed supplied to the separation unit 3a reaches a preset height, a processing operation is performed in which oil particles in the liquid to be processed are floated and separated by fine bubbles.
[0009]
At the time of processing operation, first, the circulation control valve 15 is opened, the processed liquid control valve 14 is closed, and the processed liquid in the separation unit 3 a is circulated through the pump 4. At this time, the treatment liquid air supply pipe 23 has a negative pressure due to the flow of the treatment liquid. Using this characteristic, air is introduced into the liquid air supply pipe 23 to be treated from the air introduction pipe 22. The supply air amount is adjusted by the air flow rate adjustment valve 17. Since the pump 4 rotates at a high speed, the supply air becomes fine bubbles and is easily mixed with the liquid to be treated and dissolved. By providing the nozzle 5 with a small cross-sectional area on the discharge side of the pump 4, the inside of the pressurized supply pipe 24 becomes high pressure, and the amount of air dissolved in the liquid to be processed increases. The amount of dissolved air is proportional to the amount of liquid and the pressure. In this embodiment, the air introduction pipe 22 and the air flow rate adjustment valve 17 are arranged on the suction side of the pump 4, but may be arranged on the discharge side of the pump 4 as an air introduction line '22 and an air flow rate adjustment valve '17. good. At this time, since the inside of the pressurized supply pipe 24 is at a high pressure, it is necessary to supply air at a pressure higher than the pressure in the pressurized supply pipe 24.
[0010]
The surplus air supplied from the air introduction pipe 22 does not dissolve and remains in the high-pressure liquid to be treated as bubbles. The pressure at the outlet of the pump 4 is preferably about 0.3 to 0.8 MPa in order to reduce the required power and to reduce the diameter of the fine bubbles generated after the pressure reduction. The to-be-processed liquid with the melt | dissolved air injected from the nozzle 5 and the air which is not melt | dissolved are sent to the large bubble removal part 1. FIG. Here, since the dissolved air is released from the high pressure to the atmosphere, it is generated as fine bubbles B, and the undissolved air becomes a surplus bubble A because the bubbles are enlarged by the amount released from the high pressure to the atmosphere. The surplus bubbles A having a large diameter have a high ascending speed in the liquid and gather at the upper part of the tube in the middle of the large bubble removing unit 1. As described above, the large bubble discharge pipe 9 communicating with the vicinity of the liquid surface to be treated in the treatment tank 3 is provided on the upper side in the vicinity of the outlet of the large bubble removing unit 1. It is discharged from the discharge pipe 9.
[0011]
At this time, the oil component floating and separated is simultaneously sent to the separation unit 3a of the treatment tank 3. Then, the liquid to be processed and the fine bubbles B are sent into the separation unit 3a. The fine bubbles B sent to the separation unit 3a rise and bind to the oil particles in the liquid to be treated. The oil particles accumulate as floating oil C on the liquid surface above the separation unit 3a, and the liquid to be treated is made into oil and water. To separate. When the accumulated floating oil C exceeds the height of the blocking plate 2, it flows out to the floating oil receiver 6 and is discharged from the floating oil discharge pipe 29. In addition, if it does not exceed this value, it will accumulate as floating oil C on the liquid surface. For this reason, even if it does not use the apparatus etc. which scrape the floating oil C, the process of the floating oil C is possible. The liquid to be treated in the treatment tank 3 is returned to the pump 4 through the circulation pipe 25. This processing operation is performed until a time when the liquid to be treated reaches a preset oil concentration (for example, an oil concentration of 5 mg / L or less).
[0012]
If the treatment operation is performed only for a time during which the oil concentration of the liquid to be treated is a predetermined value, the drainage operation is performed next. In the drainage operation, the discharge control valve 16 is opened and discharged to a preset liquid level. In the present embodiment, the liquid level detection at this time is performed by using the second liquid level detector 8, but the relationship between the liquid level and the discharge time may be substituted. After this discharge operation, the process liquid is returned to the process liquid supply operation, and the whole is a batch operation.
[0013]
As described above, according to the first embodiment, it is possible to efficiently separate fine bubbles and surplus air in a batch system under conventional atmospheric pressure, and it is possible to improve oil-water separation performance.
[0014]
FIG. 2 is an equipment configuration diagram showing a second embodiment of the oil-water separator according to the present invention. In FIG. 2, the same components as those shown in FIG.
[0015]
The second embodiment of the present invention is different from the first embodiment in that a receiving tank 11, a receiving tank pipe 27, a filter 12 and a filter pipe 28 are provided on the discharge port side of the discharge regulating valve 16. . The operation method is substantially the same as that of the first embodiment described above, but the processing operation time is shortened by providing the filter 12. That is, the relationship between the concentration of liquid oil to be treated in the treatment tank 3 and the time during the treatment operation is as follows: LnC = LnC ₀ -KT (C: liquid oil concentration to be treated after T time, C ₀ : initial liquid to be treated) It became clear that it can be expressed as oil concentration, K: constant, T: time). For this reason, it takes a considerable time until the oil concentration reaches a preset value (for example, oil concentration 5 mg / L or less) after the concentration becomes low to some extent (for example, about 20 to 30 mg / L).
[0016]
Accordingly, the processing operation time set in advance is shorter than that of the first embodiment, and the processing liquid after the processing operation having a low oil concentration is filtered through the tank 11 and filtered by the filter 12, thereby reducing the processing time. Can be reduced. At this time, since the oil content per unit flow rate of the processing liquid separated by the filter 12 is small, the filter life is significantly longer than that of the conventionally used filter single processing method. Moreover, since the receiving tank 11 can adjust the liquid quantity supplied to the filter 12, it can reduce the size of the filter.
[0017]
As described above, the present embodiment can improve the separation performance as compared with the prior art, and can shorten the processing time as compared with the first embodiment.
[0018]
【The invention's effect】
As described above, according to the present invention, it is possible to efficiently separate fine bubbles and excess air under normal pressure, and to obtain an oil / water separator having high oil / water separation performance.
[Brief description of the drawings]
FIG. 1 is an equipment configuration diagram showing a first embodiment of an oil-water separator according to the present invention.
FIG. 2 is an equipment configuration diagram showing a second embodiment of the oil-water separator according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Large bubble removal part, 2 ... Blocking board, 3 ... Processing tank, 3a ... Separation part, 4 ... Pump, 5 ... Nozzle, 6 ... Floating oil receptacle, 7, 8 ... Liquid level detector, 9 ... Large bubble Drain pipe, 11 ... receiving tank, 12 ... filter, 14 ... treated liquid regulating valve, 15 ... circulation regulating valve, 16 ... discharge regulating valve, 17, '17 ... air flow regulating valve, 21 ... treated liquid supply piping, 22, '22 ... Air introduction pipe, 23 ... Processed liquid air supply pipe, 24 ... Pressurized supply pipe, 25 ... Circulation pipe, 26 ... Discharge pipe, 27 ... Receiving tank pipe, 28 ... Filter pipe, 29 ... Floating oil Discharge pipe.

Claims

In a device that floats and separates oil by supplying fine bubbles into the liquid to be treated, shielding that separates between a separation unit that separates the liquid to be treated and a floating oil receiver that collects the separated oil in the treatment tank A plate is provided, a pipe for pumping out the liquid to be processed or the processed liquid in the separation unit, an air supply pipe for supplying and dissolving the air to the liquid to be processed, a pressure pump, and the air is dissolved. A processing liquid circulation system comprising a nozzle that injects a pressurized liquid to be processed and depressurizes, a floating oil discharge pipe that discharges oil accumulated in the floating oil receiver, and a discharge pipe that discharges the processed liquid A large bubble discharge pipe that mainly collects large bubbles between the nozzle and the separation unit and guides the bubbles onto the liquid surface to be treated in the separation unit, and a liquid to be treated mainly containing fine bubbles to the separation unit. A large bubble removing part having an opening for guiding is provided. Oil-water separator according to claim.

2. The oil / water separator according to claim 1, wherein the shielding plate is provided at a position higher than a liquid level inside the separation portion, and the floating oil receiving portion collects overflowed oil. 3. Separation device.

The oil-water separator according to claim 1, wherein a receiving tank for receiving the processed liquid is provided in a discharge pipe for discharging the processed liquid, and a filter for filtering the liquid from the receiving tank is further provided. Oil-water separator.