JPH10314502A - Oil water separating system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oil water separating system for cleaning drain liquid by removing an oil content in the drain liquid from a compressor. SOLUTION: Drain liquid discharged from a compressor is first housed in a tank 10 and fed from the tank 10 to an electrolyzer unit 14 by a feed water pump 12 where the drain liquid is separated to an oil content and a water content. The electrolyzer unit 14 includes an electrolyzer provided with a plurality of anode side electrode plates and cathode side electrode plates extending upward and downward. Oil sludge floating on liquid surface by gas generated by electrolysis caused by energizing both the electrode plates inside the electrolyzer is fed to a sludge-receiver 19. The oil content remaining in cleaned water cleaned by the electrolyzer is removed by adsorption tanks 23, 36.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil / water separator for separating an aqueous solution containing oil and water, for example, a drain liquid containing oil and water discharged from a compressor, into water and oil.

[0002]

2. Description of the Related Art A compressor for converting mechanical energy of an electric motor into hydraulic energy of air is supplied with lubricating oil in order to prevent direct sliding contact between members constituting the compressor. As the lubricating oil, various oils such as mineral oil, semi-mineral oil, turbine oil, reciprocating oil, and synthetic oil are used.

When a compressor is operated to supply compressed air to an actuator such as a pneumatic cylinder or a valve for controlling the operation of the actuator, lubricating oil supplied into the compressor for lubrication is compressed air. Will be discharged to the outside together with the water contained in the water.
For this purpose, a drain port is provided in the compressor, and a drain liquid containing oil and water is discharged from the drain port to the outside of the compressor.

[0004] In a factory or the like that uses a compressor, discharging the drain liquid from the compressor into a river or the ground as it is would contaminate the river and groundwater. Dumping into the ground or underground is subject to punishment under the Water Pollution Control Law.

[0005]

The main oil-water separation techniques include specific gravity difference separation, bubble separation, membrane separation, electrocoagulation, coagulation sedimentation, coalescer, adsorption, and biological treatment. Is being developed. Conventionally, in order to purify the drain liquid from the compressor, among the above-described oil-water separation technologies, those using a filter, a membrane, activated carbon or a chemical have been applied. Clogging of the filter and the like during processing became a problem, and the filter and the like had to be replaced frequently. In particular, in the case of a purification device using a membrane,
The membrane material is expensive, and frequent replacement not only increases the running cost of the purification device but also requires excessive labor for maintenance.

[0006] Further, from now on, synthetic oils such as mineral oil and semi-mineral oil which have higher viscosity and are difficult to separate oil and water tend to be frequently used for compressors. It is assumed that the purification device that separates the oil and water cannot be used.

An object of the present invention is to provide an oil-water separator for purifying a drain liquid by removing oil contained in the drain liquid from a compressor.

The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0009]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows.

That is, the oil / water separator of the present invention is an oil / water separator for separating a drain liquid discharged from a compressor into oil and moisture, and comprises a plurality of vertically extending anode-side electrode plates and a cathode. An electrolyzer having a side electrode plate, wherein the drain liquid is supplied, and an oil sludge which is disposed adjacent to the electrolyzer and floats on the liquid level in the electrolyzer due to gas generated by electrolysis. And an adsorbent incorporating an adsorbent and adsorbing oil remaining in purified water from which oil sludge has been removed by the electrolytic cell.

According to the present invention, the drain liquid discharged from the compressor is first subjected to electrolysis in an electrolytic cell to remove oil from the drain liquid, and then purified water from which the oil has been removed is passed through an adsorption means to remove the oil. Since the remaining oil that has not been removed in the tank is adsorbed and removed, oil-water separation of the drain liquid can be reliably performed, and frequent replacement of not only the electrode plate but also the adsorbent becomes unnecessary. .

The oil sludge floating on the liquid surface in the electrolytic cell is moved to the sludge receiver by a scraper provided movably in a horizontal direction above the liquid surface, or from a nozzle toward the sludge receiver. By moving the floating oil sludge to the sludge receiver by blowing compressed air, the oil sludge can be separated from moisture and discharged to the outside without fail.

The adsorbing means may be formed by a natural fiber portion filled with natural fibers and an activated carbon portion filled with activated carbon, and the adsorbing means is filled with natural fibers and passed through the electrolytic cell. It may be formed by a first adsorption tank to which purified water is supplied, and a second adsorption tank to which purified water filled with activated carbon and passed through the first adsorption tank is supplied.

Further, a tank for storing the drain liquid from the compressor, a pump for supplying the drain liquid in this tank to the electrolytic cell, and a liquid surface of the drain liquid provided in the tank and supplied therein are provided. Liquid level detecting means for detecting the level of water, operating the pump when the liquid level reaches a predetermined level, and stopping the operation of the pump when the liquid level falls below the predetermined level. You may make it drive.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(Embodiment 1) FIG. 1 is a partially cutaway front view showing an oil / water separator according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line 2-2 in FIG. Yes,
FIG. 3 is a partially cutaway right side view of FIG.

The drain liquid discharged from the compressor and containing oil and water is supplied to a tank 10 as shown in FIG. A water supply pump 12 is provided in a housing 11 serving as a purification device main body, and a drain liquid in the tank 10 is supplied to the water supply pump 1 through a passage 13.
2 is supplied. 1 and 3, reference numeral 13a indicates a drain liquid inflow section. An electrolytic cell unit 14 is disposed on the upper part of the housing 11, and a first and a second electrolytic cell 14
a and 14b are provided.

The lower part of the first electrolytic cell 14a and the water supply pump 1
A flow path 16 is connected between the second discharge port and the second discharge port, so that the drain liquid in the tank 10 is first supplied to the first electrolytic cell 14a. The drain liquid overflowing from the upper part of the first electrolytic cell 14a is supplied to both the electrolytic cells 14a,
The second electrolytic cell 14b flows into the second electrolytic cell 14b from a lower portion thereof through a passage 17 formed between the 14b.

In each of the electrolytic cells 14a and 14b,
An electrode unit constituted by alternately arranging a plurality of anode plates (for example, aluminum electrode plates) and cathode plates (for example, stainless steel electrode plates) is detachably incorporated. When, for example, a DC voltage is applied between the anode-side electrode plate and the cathode-side electrode plate, the drain liquid is electrolyzed. Due to the electrolytic action between the electrode plates, aluminum hydroxide, hydrogen gas, oxygen gas and the like are generated from the drain liquid, and the oil contained in the drain liquid is efficiently separated from the drain liquid as oil sludge. The separated oil sludge floats on the upper surfaces of the respective electrolytic cells 14a and 14b along with bubbles such as hydrogen gas and oxygen gas generated by the electrolytic action.

In the electrolysis reaction in the electrode unit,
The electrode reaction that occurs at the interface between the electrode surface and the drain solution, such as electrolysis, electrodeposition, electrolytic oxidation, electrolytic reduction, and electrolytic neutralization, that is, the primary reaction, the electrolysis product and the components in the drain solution There are secondary reactions that act, ie, precipitation, flotation, and adsorption.

As shown in FIG. 1, a scraper 18 is provided above the electrolytic cell unit 14 so as to be able to reciprocate in the horizontal direction. Oil sludge floating on the upper surfaces of the electrolytic cells 14a and 14b is removed by the electrolytic cell unit. It is taken into a sludge receiver 19 arranged adjacent to. Sludge tray 19
The oil sludge that has entered is discharged from the sludge discharge passage 20 to the outside.

The second electrolytic cell 14b also has a function as a sedimentation tank. The sediment deposited on the bottom of the second electrolytic cell 14b is discharged to the outside from the discharge port 22 through the discharge passage 21. .

The outlet of the second electrolytic cell 14b is connected to the first electrolytic cell 14b located in the housing 11 below the outlet.
As shown in FIG. 1, a passage 24 is connected to the upper inlet of the adsorption tank 23 and the second electrolytic tank 14b.
Purified water flowing out from the outlet of the first adsorption tank 23 naturally falls into the first adsorption tank 23 and flows in from the upper part thereof.

As shown in FIG. 3, the first adsorption tank 23
Cartridge 32 removably mounted in housing 31
The cartridge 32 is filled with natural fibers, and the purified water flowing into the upper portion of the housing 31 cannot be removed by the electrolytic cell unit 14 due to the natural fibers filled in the cartridge 32. Oil and coarse suspended particles are adsorbed and removed.

The purified water from which these have been removed rises upward from a space 33 formed below the cartridge 32 and is discharged from a discharge port 35 at the top of a passage 34 formed.

As shown in FIG. 1, a passage 37 is formed between the discharge port 35 and the inflow port located above the second adsorption tank 36 located at the lower part of the housing 11. The purified water that has been connected and has flowed out of the outlet of the first adsorption tank 23 naturally falls into the second adsorption tank 36, and flows in from above.

As shown in FIG. 2, the second adsorption tank 36
Cartridge 42 removably mounted in housing 41
The cartridge 42 is filled with activated carbon, and the purified water flowing into the upper part of the housing 41 is supplied to the first adsorption tank 2 by the activated carbon filled in the cartridge 42.
The oil and suspended substances that could not be removed in Step 3 are almost completely removed.

An outlet 43 is provided in the lower part of the housing 41 of the second adsorption tank 36, and the purified water treated by the second adsorption tank 36 is guided to the passage 44 by natural fall, It flows into the clear stream detector 45, and it is detected whether or not the purified water has a predetermined cleanliness. The clear stream detector 45 detects that the n-hexane value is 5 as the discharge reference value.
Purified water purified to a level of not more than ppm is discharged outside through a passage 46.

On the other hand, the separated oil sludge is scraped by a sludge scraper 18 into a sludge receiver 19, passes through a sludge discharge passage 20, is stored in an external container, and is incinerated or treated as industrial waste. . In addition, as shown in FIG.
Is attached.

The operator operates the oil / water separator shown in FIG.
The operation may be controlled by operating an operation key provided on the tank 7, but as shown in FIG.
0, a liquid level detector 48 for detecting the liquid level of the drain liquid supplied from the compressor is provided. When the liquid level becomes equal to or higher than a predetermined liquid level, the water supply pump 12 is operated, and the liquid level is equal to or lower than the predetermined liquid level. The operation may be automatically controlled so that the water supply pump 12 is stopped when.

As described above, in the illustrated oil / water separation apparatus, the treatment of the emulsified drain liquid and the emulsion liquid, which was difficult to treat by the conventional technique, is performed not by membrane but by electrolysis. The replacement frequency of the electrode plate and the adsorbent increases, and the treatment cost is reduced because no chemical is used. Moreover, the power supply used is safe because of the low DC voltage. The drain liquid can be efficiently separated into purified water and oil sludge by utilizing the electrolysis action between the electrode plates and the adsorption action by natural fibers or activated carbon. Further, the separated oil sludge can be discharged to the outside without much labor.

(Embodiment 2) FIG. 4 is a cross-sectional view showing an oil-water separator according to another embodiment, FIG. 5 is a partially cutaway left side view of FIG. 4, and FIG. 6 is FIG. 6-6 in
It is sectional drawing which follows a line, and in these figures, the same code | symbol is attached | subjected to the member common to the member in the said embodiment.

In this oil / water separator, the structure of the electrolytic cell unit 14 is the same as that of the above-described embodiment, but the oil sludge floating on the liquid surface of the electrolytic cells 14a and 14b is collected in the sludge receiver 19. For this purpose, a plurality of air nozzles 51 are provided in the electrolytic cell unit 14, and compressed air is blown out from each of the nozzles 51 so that the oil sludge is pushed into the sludge receiver 19.

In the above embodiment, the first and second adsorption tanks 23 and 36 are provided, and the first adsorption tank 23 and the second adsorption tank 23 are provided.
Are provided with natural fibers and the second adsorption tank 36 is provided with activated carbon. However, in the embodiment shown in FIGS. 4 to 6, two adsorption tanks 52 and 53 having the same structure are provided. Is provided. Each of the adsorption tanks 52, 53 is provided with an upper natural fiber portion 56 partitioned via a sponge sheet 54, 55.
And a lower activated carbon part 57.

The drain liquid supplied into the tank 10 is sequentially sent to a first electrolytic cell 14a and a second electrolytic cell 14b of an electrolytic cell unit 14 by a water supply pump 12, and is supplied by a gas generated by electrolysis. Oil sludge in the drain liquid floats on the upper surfaces of the electrolytic cells 14a and 14b. The floating oil sludge flows into the sludge receiver 19 by the air supplied from the nozzle 51 and is discharged outside through the sludge discharge passage 20. On the other hand, the electrolytic cells 14a, 14b
The particles settled at the bottom of the container are guided to the discharge passage 21 and discharged from the discharge port 22.

The purified water from which the oil sludge has been removed in this way is discharged from the electrolytic cell unit 14 and then branches into the two adsorption tanks 52 and 53 to flow into the electrolytic cells 14a and 14a.
Oil and suspended substances that could not be removed in 14b are adsorbed and removed by the natural fiber portions 56 in the adsorption tanks 52 and 53, respectively. Next, the oil and suspended substances not removed in the natural fiber portion 56 are removed by being adsorbed on the activated carbon of the activated carbon portion 57.

Although the invention made by the inventor has been specifically described based on the embodiment, the invention is not limited to the above-described embodiment, and can be variously modified without departing from the gist of the invention. Needless to say, there is.

For example, the electrolytic cell unit 14 is provided with two electrolytic cells 14a and 14b in the illustrated case.
Not limited to this, any number of electrolytic cells can be used.
In the illustrated case, the plurality of air nozzles 51 are provided in the electrolytic cell unit 14. However, a plurality of air outlets may be linearly formed as one nozzle 51.

[0039]

Advantageous effects obtained by typical ones of the inventions disclosed in the present application will be briefly described.
It is as follows.

(1) First, the drain liquid from the compressor is electrolyzed, and the oil contained therein is floated on the liquid surface as oil sludge and removed, and then the oil remaining in the purified water is adsorbed. Since the adsorbent is removed by the means, the adsorbent can be used for a long period of time, and the frequency of replacing not only the electrode plate but also the adsorbent can be reduced.

(2) Since the oil can be removed without using a chemical, the running cost of the apparatus can be reduced.

(3) Since the purified water can have a purification degree equal to or less than the discharge reference value, the purified water can be discharged as it is.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view showing an oil-water separator according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line 2-2 in FIG.

FIG. 3 is a partially cutaway right side view of FIG. 1;

FIG. 4 is a cross-sectional view showing an oil-water separator according to another embodiment of the present invention.

FIG. 5 is a partially cutaway left side view of FIG. 4;

6 is a sectional view taken along line 6-6 in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Tank 11 Housing 12 Water supply pump 13 Passage 13a Drain liquid inflow part 14 Electrolyzer unit 14a, 14b Electrolyzer 15 Housing 16, 17 Flow path 18 Scraper 19 Sludge receiver 20 Sludge discharge path 21 Discharge path 22 Discharge port 23 Adsorption tank 24 Passage 31 Housing 32 Cartridge 33 Space 34 Passage 35 Outlet 36 Adsorption tank 37 Passage 41 Housing 42 Cartridge 43 Discharge outlet 44 Passage 45 Clear stream detector 46 Passage 47 Operation panel 48 Liquid level detector 51 Nozzle 52, 53 Adsorption tank 54 , 55 Sponge sheet 56 Natural fiber part 57 Activated carbon part

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C02F 1/465

Claims (5)

[Claims] An oil / water separator for separating oil and water from an aqueous solution containing oil and water, for example, a drain liquid discharged from a compressor, comprising: a plurality of anode-side electrode plates extending vertically and a cathode. An electrolyzer having a side electrode plate, wherein the drain liquid is supplied, and an oil sludge which is disposed adjacent to the electrolyzer and floats on a liquid surface in the electrolyzer due to gas generated by electrolysis. An oil-water separation device, comprising: a sludge receiver to be cleaned; and an adsorbent incorporated therein, and an adsorbing means for adsorbing oil remaining in purified water from which oil sludge has been removed by the electrolytic cell. 2. The oil-water separation device according to claim 1,
Oil sludge floating on the liquid level in the electrolytic cell is moved to the sludge receiver by a scraper movably provided in the horizontal direction above the liquid level, or compressed air is supplied from a nozzle toward the sludge receiver. An oil-water separator, wherein the floating oil sludge is sprayed and moved to the sludge receiver. 3. The oil-water separation device according to claim 1,
An oil-water separation device, wherein the adsorption means has a natural fiber portion filled with natural fibers and an activated carbon portion filled with activated carbon. 4. The oil-water separation device according to claim 1,
The adsorption means is provided with a first adsorption tank filled with natural fibers and supplied with purified water that has passed through the electrolytic cell, and a second adsorption tank filled with activated carbon and supplied with purified water that has passed through the first adsorption tank. An oil-water separation device comprising: two adsorption tanks. 5. The oil-water separation device according to claim 1,
A tank for storing the drain liquid from the compressor, a pump for supplying the drain liquid in the tank to the electrolytic cell,
The level of the drain liquid provided in the tank is detected, and the pump is operated when the liquid level reaches a predetermined level, and the pump is operated when the liquid level falls below a predetermined level. An oil-water separation device having a liquid level detection means for stopping the operation.