JP2003038901A - Oil-water separation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve oil-water separation efficiency by recovering the deterioration of the throughput of oil-water separation due to the adsorption of oil on an oil adsorbing material in an oil-water separation apparatus. SOLUTION: An oil-water separation tank 20 is composed of an upper part tank member 21 and a lower part tank member 25 which are connected detachably. The upper tank member is divided with a permeating plate 30, the oil adsorbing material G is housed in a lower part under the plate 30 and a treated liquid outlet pipe 23 for taking out the treated liquid in which oil drops are separated is provided above the permeating plate 30. A treating liquid introducing pipe 26 for introducing a liquid to be treated and a bubbling nozzle 38 for discharging bubbles are provided in the lower part tank member. It is preferable that the treating liquid introducing pipe 26 is provided so as to produce eddy flow around the vertical center axial line in the lower part tank member and it is preferable to branch the bubbling nozzle 38 into two horizontal tip parts along the inside wall of the lower part tank member 25 and to form a plurality of air holes 39 along the longitudinal direction of the tip parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates mainly to water and coolants such as coolants for cutting or grinding, wash water after heat treatment of metals, wash water for pretreatment of coating, and bilge water of ships. The present invention relates to an oil / water separation device provided with an oil / water separation tank for adsorbing oil drops in a liquid to be treated, which are formed of the oil drops, to a lipophilic oil adsorbent to separate them from water.

[0002]

2. Description of the Related Art As an oil / water separation tank of this type, there is a technology disclosed in Japanese Patent Application Laid-Open No. 60-232212.
This involves passing an oil-water mixture through a layer of individual coalescer bodies (oil adsorbents) made of lipophilic thermoplastics having a large specific surface area and a relatively large free-flowing cross section. During this passage, fine oil droplets adhere to the surface of the coalescer body and combine with each other to form a large oil droplet, and this large oil droplet moves upward along the coalescer body and forms a large oil droplet. It floats away from the coalescer body due to the difference in specific gravity and is separated from water.

[0003]

In the conventional oil-water separation device of this type, the oil droplets adsorbed on the surface of the oil adsorbent gradually become larger and move upward along the oil adsorbent to have a specific gravity with water. Due to the difference, it floats away from the oil adsorbent, but some of the adsorbed oil droplets remain adsorbed on the surface of the oil adsorbent,
The amount increases gradually. For this reason, the resistance to the flow of the liquid to be treated increases with the passage of time and the oil-water separation treatment capacity decreases, so that there is a problem that the oil adsorbent must be taken out and replaced from time to time. The present invention aims to solve such problems.

[0004]

To this end, the oil-water separator according to the present invention is arranged such that oil droplets in a liquid to be treated, which mainly consist of water and oil droplets dispersed therein, are lipophilic in an oil-water separation tank. In the oil-water separation device that is separated from water by being adsorbed by the oil adsorbent, the oil-water separation tank is composed of an upper tank member and a lower tank member that are detachably connected, and the inside of the upper tank member is A process for partitioning with a permeable plate that allows liquid to pass through and containing an oil adsorbent in the lower part of the upper tank member that is below the permeable plate, and for removing the treated liquid in which oil droplets have been separated above the permeable plate. A liquid outlet pipe is provided, and a treatment liquid introducing pipe for introducing the treatment liquid into the lower tank member and a bubbling nozzle for discharging bubbles are provided.

The liquid to be treated sent into the lower tank member from the treatment liquid introducing pipe rises between the oil adsorbents accommodated in the lower portion of the upper tank member, and at the time of this passage, the liquid to be treated is processed. The fine oil droplets inside are adsorbed on the surface of the lipophilic oil adsorbent, are bonded and integrated with each other, and move upward along the oil adsorbent, and a considerable part becomes coarse-grained oil droplets. Enter the oil / water separation tank above the transmission plate. The coarsened oil droplets float up due to the difference in specific gravity between the liquids to be treated other than the oil droplets, which is mainly water, and are separated from the liquid to be treated, and the treated liquid from which the oil droplets have been separated is the treated liquid outlet. Taken out of the tube. If the amount of oil remaining adsorbed on the surface of the oil adsorbent increases and the resistance to the flow of the liquid to be treated increases and the oil / water separation treatment capacity declines, bubbles are emitted from the bubbling nozzle, and these bubbles adsorb the oil adsorbent. The oil adsorbed on the surface of the oil adsorbent is peeled off and separated as it rises through the space between the oil adsorbent and the air bubbles, and then it is removed together with the air bubbles and enters the oil / water separation tank above the permeation plate to become waste oil. .
As a result, the flow resistance of the liquid to be treated passing through the oil adsorbent is reduced, and the oil / water separation treatment capacity is restored.

The treatment liquid introducing pipe of the oil-water separator according to the present invention is provided so as to be oriented along the inner wall surface of the lower tank member so as to generate a vortex flow around the vertical central axis in the lower tank member. Is preferred.

Further, the bubbling nozzle of the oil-water separator according to the present invention is branched into two horizontal end portions along the inner wall surface of the lower tank member, and a plurality of air holes are provided at each end portion in the longitudinal direction. It is preferably formed.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The oil-water separator according to the present invention will be described below with reference to the embodiments shown in FIGS. As schematically shown in FIG. 1, the oil-water separation device of this embodiment is mainly composed of oil-water separation tank 20 which is a central part, and mainly water such as coolant in a storage tank 40 attached to a grinder or the like. A pump P for feeding an aqueous liquid to be treated consisting of oil droplets dispersed in the oil into the oil / water separation tank 20 via a feed conduit 41, and a treated liquid tank in which the treated liquid in which the oil droplets have been separated in the oil / water separation tank 20 is stored. Returning process liquid return pipe 4
4 and the treatment liquid drain pipe 47, a waste oil discharge pipe 48 for discharging the waste oil consisting of oil droplets separated in the oil / water separation tank 20 to a waste oil container 49, a bubbling nozzle 38 provided in the lower portion of the oil / water separation tank 20, The bubbling nozzle 38 is provided with a bubbling air supply path 51 for supplying pressurized air from an air inlet 50. A filter device 42 and a backwashing liquid reservoir 43 are provided in the feed pipe line 41, and a backwashing air supply passage 52 for introducing pressurized air from an air inlet 50 is connected to the feeding pipe line 41, and a motor valve provided in each pipe. The operation of the solenoid valves MV1 to MV3 and SV1 to SV4 is controlled by the controller 55.

As shown in FIGS. 2 and 3, the support base 10 for supporting these parts except the storage tank 40 has a floor plate 10b fixed to the upper side of a square frame-shaped frame 10a made by welding channel steel. The caster wheels 11 for supporting the oil-water separator are provided on the reinforcing plate 10c welded and fixed to the lower four corners of the support base 10. Support stand 10
The oil-water separation tank 20 and the pump P are arranged in the slightly wide first area A1 on the upper rear side, and each motor valve and the solenoid valve MV1 to the slightly narrow second area A2 on the front side.
A storage box 15 for storing MV3, SV1 to SV4, etc., a filtering device 42, and a backwashing liquid reservoir 43 are arranged, and a waste oil container 49 that can be taken out is mounted. In the two corners on the right side of the second area A2, the corner posts 1 having the same height as the storage box 15
6 and the middle support 17 are erected, and the storage box 15 and both support 1
The control box 14 that houses the control device 55 is mounted on the control boxes 6 and 17.

The oil / water separation tank 20 has an upper tank member 21 having a lid plate 22 as shown mainly in FIGS.
And the lower tank member 25 has a cylindrical shape. Each part is made of iron, and the lid plate 22 is liquid-tightly and detachably fixed to the upper flange 21b of the upper tank member 21 by 12 sets of bolts and nuts 29a.
The flange 25a to the lower flange 2 of the upper tank member 21.
It is liquid-tightly and detachably fixed to 1a by tightening 12 sets of bolts and nuts 29a. An intermediate flange 21c is welded and fixed to the inner surface of the intermediate portion of the upper tank member 21 in the vertical direction, and the inside of the oil / water separation tank 20 is an upper transmission plate (transmission plate) fixed to the upper surface of the intermediate flange 21c by six bolts 32. 30 and the lower flange 2
The lower transmission plate 31 fixed to the lower surface of the inwardly projecting portion of 1a by six bolts 32 divides the lower introduction chamber R1, the intermediate adsorption coarsening chamber R2, and the upper oil / water separation chamber R3. Has been done. The upper transmission plate 30 has many large opening holes 30.
A liquid obtained by spot-welding a wire mesh 30b on the lower surface of the perforated plate 30a on which a1 is formed is capable of passing a liquid, and the lower transmission plate 31 has a point where the metal net 31b is provided on the upper surface of the perforated plate 31a. Except for the above, it has the same structure as the upper transmission plate 30.

Lower tank member 25 forming the introduction chamber R1
Four support legs 27 are welded and fixed to the side surface of the support plate 27, and a mounting plate 27a at the lower end of each support leg 27 is bolted and fixed to the first area A1 on the support base 10. Lower tank member 25
A manual drain valve 28 is provided at the drain port 25b formed at the bottom of the.

An oil adsorbent G made up of a large number of granules made of a lipophilic thermoplastic resin such as polypropylene resin is housed in the adsorption coarsening chamber R2. This oil adsorbent G
Granules have irregular shape with irregularities, and their diameter is 60
It is about 0 to 700 μm. The actual volume of the oil adsorbent G when the granules are filled in the adsorption coarsening chamber R2 is approximately 70% of the volume of the adsorption coarsening chamber R2 because there is a physical gap. Packing amount of granules in the adsorption coarsening chamber R2 (Injecting the granules into the adsorption coarsening chamber R2 from above without a treatment liquid, and applying a load of 2 to 20 kg per hand to the operator's palm The value when pressed tightly several times to a few dozen times) is 100% when the adsorption coarsening chamber R2 is fully filled with granules (the oil adsorbent G at this time G
Is about 74% of the weight obtained by the volume of the adsorption coarsening chamber R2 times the specific gravity of the oil adsorbent G, assuming that the granules are spherical). And, if the filling amount of the granules is 100%, the total surface area of the granules becomes maximum, the oil adsorption capacity becomes large, and the oil separation capacity becomes maximum. On the other hand, in bubbling (described later), in which the oil adsorbed on the surface of the granules is separated and floated to recover the oil adsorption capacity of the granules, it is possible to sufficiently recover the oil adsorption capacity even if the granule filling amount is 100%. However, in order to save the oil adsorbent G while ensuring the oil adsorption capacity of the granules without causing any trouble, the filling amount of the granules may be reduced to about 45%. In this case, during bubbling, the granules collide with each other and the oil is easily separated from the granules, and the separated oil is less likely to be adsorbed again on the surface of the granules while floating, so bubbling for a short time can recover the oil adsorption capacity. is there.
If the filling amount is 45% or less, the chances of collision of the granules during bubbling are reduced, so that the efficiency of oil adsorption capacity recovery is reduced.

The size of the meshes of the wire nets 30b and 31b is such that the oil adsorbent G cannot pass through (100 to 2).
00 mesh). Since polypropylene resin has a smaller specific gravity than water, the filling amount of granular oil adsorbent G is 1
When it is less than 00%, a large number of granular oil adsorbents G float up to the upper permeable plate 30 side in the state where the aqueous liquid to be treated in which the oil droplets are dispersed is supplied into the oil-water separation tank 20, and are layered. Becomes

In the oil / water separation chamber R3, a vertically extending iron guide 35 made of a rotor having an eight-shaped cross section is mounted on a perforated plate 30a. The lower edge of the guide 35 can be moved in the radial direction to some extent until it hits the head of the bolt 32, but at any position thereof, the perforated plate 30 is provided.
A plurality of communication holes 35a that do not enter the opening hole 30a1 of a and communicate with the inside and outside of the guide 35 formed near the lower edge thereof are also positioned substantially outside the opening hole 30a1. Therefore, only the inside of the guide 35 is connected to the inside of the adsorption coarsening chamber R2 containing the oil adsorbent G via the upper transmission plate 30. Instead of the communication hole 35a, the guide 3
A plurality of notches that communicate the inside and outside may be provided at the lower edge of 5.

A guide 35 is provided on the side wall of the upper tank member 21.
A drain port 21d is formed in the lower part of the oil / water separation chamber R3 on the outer side of the processing liquid outlet pipe 23. The lower end of the processing liquid outlet pipe 23 is fixed so as to liquid-tightly penetrate the peripheral portion of the lid plate 22 and extends downward. It opens at the lower part inside the oil / water separation chamber R3, which is outside the guide 35. A cylindrical upper protrusion 22a forming a waste oil reservoir R3a which is an upper portion of the oil / water separation chamber R3 is formed on the upper side of the central portion of the cover plate 22, and an automatic air vent valve 36 is provided on the upper side of the upper protrusion 22a. Has been. This automatic air bleeding valve 36 allows the inside of the waste oil reservoir R3a to communicate with the outside air unless liquid enters the inside, but the oil / water separation chamber R
This is a float valve that shuts off the communication between the inside of the waste oil reservoir R3a and the outside air when the liquid level of the waste oil in 3 or the treated liquid level rises and enters the inside. A waste oil reservoir R is provided on the side surface of the upper protruding portion 22a.
A waste oil outlet 22b (see FIG. 3) that opens at the upper part of the inside of 3a is provided.

The guide 35 may be a plate member that extends vertically and partitions at least the lower half of the inside of the oil / water separation chamber R3 into two parts in the horizontal direction. Therefore, as in this embodiment, the oil / water separation tank is used. The plate-shaped member is not limited to the one provided coaxially with 20, but is provided on one side in the oil / water separation chamber R3 and extends vertically and except the upper edge is welded and fixed to the side wall of the upper tank member 21 and the intermediate flange 21c. But it's okay. In this case, the lower ends of the liquid outlet 21d and the processing liquid outlet pipe 23 may be opened in the space between the plate-shaped member forming the guide 35 and the upper tank member 21.

The processed liquid in the upper part of the oil / water separation chamber R3 including the waste oil sump R3a is provided above the level detection pipe 37 whose upper end is fixed in a liquid-tight manner at the center of the top plate of the upper protruding portion 22a and extends downward. And a float switch F that detects the height of the boundary surface with the waste oil that has been separated and floated above and accumulated above it.
S1 is provided, and a float switch FS2 for detecting the height of the lower liquid level in the oil / water separation chamber R3 is provided below the level detection pipe 37. Float switch FS1
Has a float FS1a which is smaller than the specific gravity of the treated liquid and larger than the specific gravity of the waste oil above it, and is provided outside the level detection pipe 37 so as to be slidable in the vertical direction,
The magnet provided in the float FS1a actuates the reed switch provided in the level detection pipe 37. When the boundary surface between the treated liquid and the waste oil is lowered, the waste oil discharge pipe 48 to the waste oil reservoir R3a is operated. Open above the first predetermined position lower than the opening position and higher than the opening position of the processing liquid outlet pipe 23 to the oil / water separation chamber R3, and open above the first predetermined position when the boundary surface rises to the waste oil reservoir R3a. The waste oil discharge pipe 48 is closed when the second predetermined position lower than the opening position of the waste oil discharge pipe 48 is exceeded. The float switch FS2 operates a reed switch similar to the float switch FS1 except that the specific gravity of the float FS2a is only smaller than the specific gravity of the treated liquid, and the treated liquid level in the oil / water separation chamber R3 is lowered. In the case, it opens below the third predetermined position which is lower than the upper edge of the guide 35 and higher than the opening position of the processing liquid outlet pipe 23 to the oil / water separation chamber R3, and when the processed liquid level rises, it opens from the third predetermined position. It closes when it exceeds a high fourth predetermined position.

The bubbling nozzle 38 has a short tubular mounting portion 38c which is liquid-tightly horizontally penetrating the side wall of the lower tank member 25 and fixed thereto, a base end portion 38a which is screwed and fixed to the mounting portion 38c, and this base portion. Two dogleg-shaped tip portions 3 branched from the tip of the end portion 38a and arranged so as to form a quadrangle along the inner surface of the lower tank member 25 in a plan view.
8b and an elbow 38d screwed and fixed to the outside of the mounting portion 38c, and each tip portion 38b is supported by a stay 25c welded to the inner surface of the lower tank member 25. The tip of each tip portion 38b is closed, and nine air holes 39 are formed along the upper side. Further, the lower tank member 25 is provided with a processing liquid introducing pipe 26 for horizontally feeding the liquid to be processed from the feed pipe line 41.
It is welded and fixed to the inner wall surface of the cylinder so as to be oriented almost in the tangential direction. As a result, the processing liquid introducing pipe 2
The liquid to be treated introduced into the lower tank member 25 from 6
Since a vertical vortex flow around the central axis is generated in the lower tank member 25, oil droplets having a small specific gravity in the liquid to be treated are collected at the center and prevented from adhering to the inner wall surface of the lower tank member 25.

As shown in FIGS. 1 to 3, in the pump P, the pressurized air from the multipurpose compressed air source connected to the air inlet 50 is reduced to a predetermined pressure by the pressure regulator PR1 and the solenoid valve SV1 and The liquid to be treated, which is supplied and driven through the air supply path provided with the check valve CV1, and which is sucked from the storage tank 40 through the suction pipe 45, is fed into the feed conduit 4
1 and the treatment liquid introducing pipe 26 to separate the oil / water separation tank 20.
It is sent to the introduction chamber R1. A check valve CV2, a filtration device 42, a backwash liquid reservoir 43, and a motor valve MV1 are provided in series between the pump P and the oil / water separation tank 20 in this order from the pump P side, and between the pump P and the check valve CV2. Is equipped with a pressure switch PS1 for detecting the upstream pressure of the filtration device 42 and a pressure gauge PM1, and a motor valve MV1 and an oil / water separation tank 2 are provided.
Between 0, a pressure switch (oil adsorption amount detection means) PS2 for detecting the supply pressure of the liquid to be treated to the oil / water separation tank 20 and a pressure gauge PM2 are provided.

As shown in FIGS. 2 and 3, the filtration device 4
2 and the backwash liquid reservoir 43 are the rear side plate 15c of the storage box 15.
And a vertical support plate 18 whose right and left ends are fixed to the middle pillar 17
Are mounted side by side. As shown in FIG. 1, the tubular filter element 42a provided inside the filtering device 42 is provided on the upstream side, which is the pump P side on the outer side, and coaxially provided on the inner side, inside the backwashing liquid reservoir 43. It is communicated with the upper end of the narrow pipe 43a. The lower part inside the filtration device 42, which is outside the filter element 42a, is accommodated in the storage tank 4 via a backwash liquid return pipe 46 equipped with a motor valve MV2.
0 or a processed liquid tank (not shown).

As shown in FIGS. 1 and 6, the guide 35
The processing liquid outlet 23 a at the upper end of the processing liquid outlet pipe 23 having a lower end opened to the lower portion inside the oil / water separation chamber R 3 on the outer side of is directly connected to the storage tank 40 via the processing liquid return pipe 44. The liquid drain port 21d provided in the upper tank member 21 and opening to the lower part of the oil / water separation chamber R3 is communicated with the storage tank 40 via a processing liquid drain pipe 47 provided with a motor valve MV3. In addition, the waste oil outlet 22b that opens at the upper part of the waste oil reservoir R3a is connected to a waste oil container 49 via a waste oil discharge pipe 48 provided with a solenoid valve SV2.

As shown in FIG. 1, a bubbling nozzle 38
The compressed air from the multipurpose compressed air source connected to the air inlet 50 is depressurized to a predetermined pressure by the pressure regulator PR2, and the bubbling air supply path 51 provided with the solenoid valve SV4 and the check valve CV4 is provided. It is designed to be supplied via. In addition, the backwash liquid reservoir 43 and the motor valve MV
The pressure regulator PR
Pressurized air reduced to a predetermined pressure by the solenoid valve SV3
Further, the air is supplied through the backwash air supply path 52 provided with the check valve CV3.

A control panel (not shown) operated by an operator, pressure switches PS1 and PS2, float switches FS
1, the control device 55 for controlling the motor valves MV1 to MV3 and the solenoid valves SV1 to SV4 based on the input from FS2 and the control program stored in the storage device to operate the oil-water separator is the storage box 15 It is housed in a control box 14 mounted above the corner support 16 and the middle support 17.

As shown in FIGS. 2 and 3, the storage box 15 provided on the left side of the front part of the support base 10 is hinged to the left and right and rear side plates 15a, the ceiling plate 15e and the left side plate 15a so as to be openable and closable. The front door 15d is stopped and accommodates the motor valves MV1 to MV3, the solenoid valves SV1 to SV4, the pressure switches PS1 and PS2, and the pressure regulator PR2. Pressure gauges PM1 and PM2 are front door 15d
Is provided on the upper part of. Also pressure regulator PR1
Is attached to the outer surface of the right side plate 15b of the storage box 15. The pressure regulator PR1 is equipped with a lubricator that supplies the lubricating oil necessary for driving the pump P, and this lubricating oil is also discharged from the exhaust pipe of the pump P. Therefore, the tip of this exhaust pipe is placed inside the waste oil container 49. It is opened (not shown).

Next, the operation of the above-described embodiment will be described with reference to the flowchart shown in FIG. In the state where the oil / water separation device is stopped and the liquid to be treated is not supplied to the oil / water separation tank 20, the motor valve MV1 is open, and the motor valves MV2, MV3 and the solenoid valves SV1 to SV4 are closed. Further, all the pressure switches PS1 and PS2 and the respective float switches FS1 and FS2 are open.
In the liquid to be treated in the storage tank 40, a coarse solid substance is precipitated in advance and removed by a separator (not shown).

When the operation switch of the operation panel is turned on, the control device 55 starts the operation shown in the flowchart of FIG.
First, the control device 55 starts the operation of the pump P by opening the solenoid valve SV1 (step 101). Pump P
Since the pressure switches PS1 and PS2 are both opened immediately after the start of the operation of, the control device 55 executes the control operation in step 10
From 2, 103, the process proceeds to step 104 to start the oil-water separation operation. In this state, the liquid to be treated in the storage tank 40, which has been sucked through the suction pipe 45 by the operation of the pump P, has the mixed fine particles of solid matter removed by the filtration device 42, and is passed through the feed pipe line 41 to obtain the oil water. It is supplied to the introduction chamber R1 of the separation tank 20. As a result, the oil / water separation tank 2
The liquid level in 0 gradually rises (the rising speed is, for example, 20 cm
/ Min) until the treated liquid level in the oil / water separation chamber R3 rises to reach the second predetermined position and the float switch FS1 is closed, the control device 55 opens the solenoid valve SV2 (steps 105, 106). ). Therefore, oil-water separation tank 2
The air in 0 is first discharged from the automatic air vent valve 36, the processing liquid return pipe 44, and the waste oil discharge pipe 48. The liquid level in the oil / water separation tank 20 rises and enters the oil / water separation chamber R3,
When the lower end of the treatment liquid outlet pipe 23 is exceeded, the discharge of air from the treatment liquid return pipe 44 is stopped, and the treated liquid surface further rises to reach the second predetermined position and the float switch FS1 is closed, and the control device 55 is reached. Closes the solenoid valve SV2 (steps 105 and 107) to stop the discharge of air from the waste oil discharge pipe 48, and thereafter, the same amount of the treated liquid supplied by the pump P as the treated liquid is the treated liquid return pipe. It is returned from 44 to the storage tank 40 or the processed liquid tank (not shown). When the treated liquid level further rises and enters the automatic air bleeding valve 36, the automatic air bleeding valve 36 is closed to prevent liquid leakage from the automatic air bleeding valve 36.

In the oil-water separation operation of step 104, the liquid to be treated sent into the introduction chamber R1 of the oil-water separation tank 20 enters the adsorption coarse-graining chamber R2 from the lower permeable plate 31 and enters the adsorption coarse-graining chamber R2. Except for the lower part, it rises up between a large number of granular oil adsorbents G formed in a layered manner, and the fine oil droplets dispersed in the liquid to be treated during this passage adsorb lipophilic oil. The material G is adsorbed on the surface of the material G and bonded to each other to be integrated with each other. The integrated oil droplets gradually move upward along the oil adsorbent G, and a considerable portion of the oil droplets passes through the upper transmission plate 30 to become roughened oil droplets and enters the adsorption roughening chamber R2. Due to the difference in specific gravity from the treated liquid other than the oil droplets, which mainly consists of water, it floats and is separated from the treated liquid, and accumulates in the upper part of the oil / water separation chamber R3 including the waste oil reservoir R3a. The floating coarsened oil droplets are collected by the guide 35 in the central portion of the oil / water separation chamber R3, and the portion outside the guide 35 in the lower portion of the oil / water separation chamber R3 where the lower end of the treatment liquid outlet pipe 23 is opened is ,
The treated liquid becomes a treated liquid in which oil droplets have been removed, and the treated liquid is fed from the treatment liquid outlet pipe 23 to the treatment liquid return pipe 44.
And is returned to the storage tank 40 through the. The communication hole 35a provided in the lower portion of the guide 35 is an opening hole 30a1 of the upper transmission plate 30.
Since it is located substantially outside, the floating coarsened oil droplets do not come out of the guide 35 from the communication hole 35a.

By this oil / water separation operation, the amount of waste oil, which is separated from the liquid to be treated and is accumulated in the upper part of the oil / water separation chamber R3, increases, and the boundary surface between this waste oil and the treated liquid below it increases. If the height falls below the first predetermined position, the float switch FS1 is opened, which causes the control device 55 to open the solenoid valve SV2 (steps 105 and 106).
The waste oil collected in the upper part of the oil / water separation chamber R3 is the waste oil discharge pipe 4
It is discharged from 8 to the waste oil container 49. When the waste oil is discharged and the height of the boundary surface between the waste oil and the treated liquid rises to the second predetermined position, the float switch FS1 is closed, which causes the control device 55 to close the solenoid valve SV2 (step 10).
5, 107) Prevent the treated liquid from being discharged from the waste oil discharge pipe 48. The above operation is repeated in the oil-water separation operation, the processed liquid in which the oil droplets have been separated from the liquid to be processed is returned to the storage tank 40, and the separated waste liquid is the waste oil container 4
The liquid to be treated in the storage tank 40 has the oil droplets removed.

When this oil-water separation operation is continued, the amount of oil remaining adsorbed on the surface of the granular oil adsorbent G gradually increases and the area through which the liquid to be treated can freely pass decreases. The resistance to the circulation of oil gradually increases and the processing capacity of oil-water separation decreases. Due to this increase in resistance, the supply pressure of the liquid to be treated to the oil / water separation tank 20 rises, and when it exceeds a predetermined limit, the pressure switch PS2 is closed. In this state, the inside of the oil / water separation chamber R3 is returned to the storage tank 40 at atmospheric pressure via the processing liquid outlet pipe 23 and the processing liquid return pipe 44, and therefore the pressure of the liquid to be treated supplied to the oil / water separation tank 20 at this time. Corresponds to the pressure difference before and after the oil adsorbent G of the liquid to be treated passing through the oil adsorbent G contained in the adsorption coarsening chamber R2, in a one-to-one correspondence. When the pressure switch PS2 is closed, the control device 55 advances the control operation from step 103 to step 110, stops the oil / water separation operation, and performs bubbling to restore the oil / water separation treatment capacity. The controller 55 first closes the solenoid valve SV1 to stop the pump P and opens the motor valve MV3 (steps 110, 11).
1), air is introduced from the automatic air vent valve 36 to lower the liquid level in the oil / water separation chamber R3, and after a predetermined time T1 (for example, 5 seconds), the solenoid valve SV2 is opened (step 112 to step 114). Air is also introduced from 48 to quickly lower the liquid level in the oil / water separation chamber R3. Although the inside of the oil / water separation chamber R3 is separated into the inside and outside by the guide 35, the liquid level inside and outside the guide 35 is simultaneously lowered by the action of the communication hole 35a provided in the lower part of the guide 35. Then, if the treated liquid level in the oil / water separation chamber R3 becomes lower than the third predetermined position and the float switch FS2 is opened (step 11).
5), the controller 55 opens the solenoid valve SV4 for a predetermined time T2 (for example, 5 seconds) (steps 116 to 118), and supplies pressurized air from the pressure regulator PR2 to the bubbling nozzle 38 via the bubbling air supply path 51. Then, bubbles are discharged from each air hole 39 of the bubbling nozzle 38 to start bubbling.

The bubbles discharged from the bubbling nozzle 38 enter the adsorption coarsening chamber R2 from the lower permeable plate 31 and float up in layers except for the lower part of the adsorption coarsening chamber R2 to form a large number of granular oils. By rising between the adsorbents G, the oil adsorbed on the surface of the oil adsorbent G is separated by the bubbles. As described above, when the filling amount of the granules is an appropriate value less than 100%, the oil adsorbed on the surface of the oil adsorbent G is separated even when the granules collide with each other. The oil separated from the oil adsorbent G in this way is
Ascends with the bubbles passing between the oil adsorbent G and is removed,
It passes through the upper permeable plate 30 and enters the oil / water separation chamber R3 to become waste oil. As a result, the oil that remains adsorbed on the surface of the oil adsorbent G is removed, so that the flow resistance of the liquid to be treated passing through the oil adsorbent G is reduced, and the oil-water separation treatment capacity is restored. In the oil / water separation chamber R3, substantially only the inside of the guide 35 is communicated with the adsorption coarsening chamber R2 via the upper permeable plate 30, so that the waste oil made of oil separated from the oil adsorbent G is used. Collects on the treated liquid inside the guide 35,
Bubbled by bubbling air, but oil / water separation chamber R
Since the liquid level in 3 is lower than the upper edge of the guide 35,
This waste oil hardly comes out of the guide 35 where the processing liquid outlet pipe 23 and the processing liquid drain pipe 47 are opened.

Since the amount of air for bubbling sent into the oil / water separation chamber R3 during the oil / water separation operation is large, the waste oil discharge pipe 4 in which the automatic air vent valve 36 and the solenoid valve SV2 are opened.
It is not possible to completely discharge it from only 8 and the treated liquid in the oil / water separation chamber R3 is also returned to the storage tank 40 from the treatment liquid outlet pipe 23 and the treatment liquid return pipe 44. As a result, the oil / water separation chamber R
The liquid level of the treated liquid in 3 also decreases, and when this liquid level reaches the lower end of the treatment liquid outlet pipe 23, the bubbling air is also discharged from the treatment liquid outlet pipe 23 and the treatment liquid return pipe 44. Become.

After performing the bubbling for a predetermined time T2, the controller 55 closes the electromagnetic valve SV4 and the motor valve MV3 (step 119) to stop the bubbling, and returns the control operation to step 101. If the flow resistance of the oil adsorbent G is sufficiently reduced by bubbling and the pressure switch PS2 is opened, the oil-water separation operation of step 104 is restarted, and the flow resistance of the oil adsorbent G is not sufficiently reduced and the pressure switch PS2 remains closed. If there is, the controller 55 advances the control operation again to step 110 and repeats bubbling. In this embodiment, the control device 55 controls the pressure switch P so that the supply pressure of the liquid to be treated to the oil / water separation tank 20 rises and exceeds a predetermined limit.
Although bubbling is performed when S2 is closed, a timer is provided to calculate a cumulative value of the oil-water separation operation time of step 104 after the last bubbling is completed, and bubbling is started when the cumulative value reaches a predetermined time. You may do it. This time measuring means may be constituted by a program installed in a control device that controls the operation of the oil-water separation device.

The fine solid matter mixed in the liquid to be treated, which is sent to the oil / water separation tank 20 by the pump P, is captured and removed by the filter element 42a of the filtering device 42 provided in the middle of the feeding pipe line 41. . The amount of fine solid particles trapped in the filter element 42a increases, the flow resistance of the filtering device 42 increases, and the filtering capacity decreases. When the upstream pressure of the filtration device 42 rises due to this increase in flow resistance and the pressure switch PS1 is closed beyond a predetermined limit, the control device 55 advances the control operation from step 102 to step 120 to stop the oil / water separation operation. Backwashing is performed to restore the filtering capability of the filtering device 42. In this back washing, the control device 55 first closes the solenoid valve SV1 to stop the pump P (step 120), and the motor valve MV1.
Is closed and the motor valve MV2 is opened (step 121), and a small time is allowed to decrease the pressure on the upstream side of the filtering device 42, and then the solenoid valve SV3 is opened for a predetermined time T3 (for example, 5 seconds) (steps 122 to 124). As a result, pressurized air is supplied to the downstream side of the backwashing liquid reservoir 43 through the backwashing liquid supply path 52, and the liquid to be treated in the backwashing liquid reservoir 43 is fed from the central pipe 43a to the center side of the filtering device 42. Enters and flows back through the filter element 42a. Due to this backflow, the fine solid particles captured by the filter element 42a are removed and discharged from the backwash liquid return pipe 46 to the storage tank 40 (or another waste liquid container). As a result, the resistance of the filter element 42a to the flow of the liquid to be treated is reduced, and the filtration capacity of the filtration device 42 is restored.

After performing this backwashing for a predetermined time T3, the control device 55 closes the solenoid valve SV3 and the motor valve MV2 to stop the backwashing and opens the motor valve MV1 (step 125), and the control operation is performed in step 101. Return to. If the flow resistance of the filter element 42a is sufficiently reduced by the back washing and the pressure switch PS1 is opened, the oil-water separation operation of step 104 is restarted, and the flow resistance of the filter element 42a is not sufficiently reduced and the pressure switch PS1 remains closed. For example, the control device 55 performs the control operation again in step 12
Go to 0 and repeat backwash. In this embodiment, the control device 55 performs the back washing when the upstream pressure of the filtering device 42 rises and exceeds the predetermined limit and the pressure switch PS1 is closed. The cumulative value of the separation operation time may be detected by the time measuring means, and bubbling may be started when the cumulative value reaches the predetermined time.

The operation of the oil / water separation device is stopped by pressing the stop switch on the operation panel at any time during the operation of the oil / water separation device. If necessary, the drain valve 28 is manually opened to drain all the liquid in the oil / water separation tank 20.

According to the above-described embodiment, the bubbling nozzle 38 is provided in the introduction chamber R1 of the oil / water separation tank 20 to increase the amount of oil remaining adsorbed by the oil adsorbent G and to prevent the flow of the liquid to be treated. When the resistance increases and the oil-water separation treatment capacity decreases, the supply of the liquid to be treated into the lower tank member 25 is stopped, and bubbles are emitted from the bubbling nozzle 38 to adsorb on the surface of the oil adsorbent. The oil that has been separated is separated and rises along with the air bubbles to be removed, whereby the resistance to the flow of the liquid to be treated is reduced and the oil-water separation treatment capacity is restored. Therefore, this oil-water separator can be used for a long period of time without taking out and replacing the oil adsorbent. In the above-described embodiment, the oil adsorbent G is composed of a large number of lipophilic granules, and when the granule filling amount is set to an appropriate value less than 100%, the oil adsorbent G is adsorbed on the surface of the oil adsorbent G. Since the oil that has been used is peeled off even when the granules collide with each other, the recovery of the oil / water separation treatment capacity can be performed more completely and quickly, but the present invention is not limited to this, and the fibrous or porous oil adsorption is possible. The present invention can also be applied to an oil / water separator using a material, and the oil adsorbed on the surface of the oil adsorbent G by bubbles is removed in the same manner as in the above-described embodiment.

In the above-described embodiment, the upper tank member 21 in which the oil / water separation tank 20 is detachably connected to each other.
Since it is composed of the lower tank member 25, the oil and water separation tank 20 can be easily disassembled and inspected.

Further, since the treatment liquid introducing pipe 26 is provided so as to be oriented in the direction along the inner wall surface of the lower tank member 25, a vortex flow around the vertical central axis line is generated in the lower tank member 25, which causes the treatment. Oil droplets having a small specific gravity in the target liquid are collected in the center and are prevented from adhering to the inner wall surface of the lower tank member 25. Thereby, the separation efficiency of the oil droplets in the liquid to be treated is improved.

Further, the bubbling nozzle 38 is branched into two horizontal tip portions 38a along the inner wall surface of the lower tank member 25, and a plurality of air holes 39 are formed in each tip portion 38a along the longitudinal direction. Therefore, the air bubbles discharged from each air hole 39 are raised almost uniformly in the lower tank member 25 in the circumferential direction, and the oil-water separation treatment capacity of the large number of oil adsorbents G is uniformly restored. The oil / water separation treatment capacity is efficiently restored.

Further, in the above-described embodiment, the feeding pipe line 4
1 is provided with a filtering device 42 and a backwashing liquid reservoir 43 to remove fine solids contained in the liquid to be treated,
If the amount of fine solid particles captured by the filter element 42a increases and the flow resistance increases, the backwash liquid reservoir 43
Since the liquid to be treated in the inside is made to flow back to the filtering device 42 by the pressurized air to remove the fine solid particles trapped in the filter element 42a, the filtering ability of the filtering device 42 is restored. The oil-water separator can be used for a long period of time without replacing 42a.

In the above-described embodiment, bubbling is started when the treated liquid level in the oil / water separation chamber R3 drops to the first predetermined position and the float switch FS2 opens. The start time may be any time after the time when the treated liquid level becomes lower than the upper edge of the guide 35. Therefore, step 115 can be omitted by setting the above-mentioned predetermined time T1 so that the solenoid valve SV2 opens after the treated liquid level becomes lower than the upper edge of the guide 35. The motor valve MV3 may be closed at the start of bubbling in step 116, instead of being closed at the end of bubbling as in the above-described embodiment.

Next, the operation of the modification of the above-described embodiment will be described with reference to the flow chart shown in FIG. The structure of this modified example is the same as that of the above-described embodiment except that the processing liquid drain pipe 47, the motor valve MV3 and the float switch FS2 provided therein are omitted. Further, the operations of the oil-water separation in steps 104 to 107 and the back washing in steps 120-125 are the same as those in the above-described embodiment, and only the operation of bubbling for recovering the oil-water separation treatment capacity is different. Will be described only.

Similar to the above-described embodiment, also in this modification, the supply pressure of the liquid to be treated to the oil / water separation tank 20 rises during the oil / water separation operation and exceeds the predetermined limit, so that the pressure switch PS
2 is closed, the controller 55 starts the control operation in step 10
From 3 to step 210, bubbling is performed. The controller 55 first closes the solenoid valve SV1 to stop the pump P (step 210), closes the solenoid valve SV2 (step 211), and then opens the solenoid valve SV4 for a predetermined time T4 (for example, 5 seconds) (steps 212 to 212). 216), pressurized air from the pressure regulator PR2 is supplied to the bubbling nozzle 38 via the bubbling air supply path 51, and bubbles are discharged from each air hole 39 of the bubbling nozzle 38 to start bubbling.

During the bubbling, the bubbles emitted from the bubbling nozzle 38 enter the adsorption coarsening chamber R2 from the lower permeable plate 31 and rise up in layers except the lower portion thereof, as in the above-described embodiment. The oil adsorbed on the surface of the oil adsorbent G is peeled off by ascending through a large number of granular oil adsorbents G and rises and is removed together with the bubbles passing between the oil adsorbent G. Then, it passes through the upper permeable plate 30 and enters the oil / water separation chamber R3 to become waste oil. The air for bubbling that has entered the oil / water separation chamber R3 is the automatic air vent valve 3
6 does not completely escape, and collects in the upper part of the oil / water separation chamber R3, and the treated liquid in an amount corresponding to the volume of the accumulated air is returned from the treatment liquid outlet pipe 23 to the storage tank 40 through the treatment liquid return pipe 44. As a result, the treated liquid level in the oil / water separation chamber R3 gradually decreases. Predetermined time T4a from the start of bubbling
(<T4, the time until the treated liquid level falls to the fifth predetermined position lower than the upper edge of the guide 35, for example, 2 seconds), the control device 55 opens the solenoid valve SV2 (step 214). , 215).

In this state, as in the above-described embodiment, the waste oil consisting of the oil separated from the oil adsorbent G and entering the oil / water separation chamber R3 collects on the treated liquid inside the guide 35, Although bubbled by bubbling air, since the liquid level in the oil / water separation chamber R3 is lower than the upper edge of the guide 35, this waste oil is discharged from the guide 35 where the treatment liquid outlet pipe 23 and the treatment liquid drain pipe 47 are opened. It rarely goes outside. Since the amount of bubbling air sent into the oil / water separation chamber R3 during the oil / water separation operation is large, even in this state, the automatic air bleeding valve 36 and the solenoid valve SV2 cannot be exhausted only from the waste oil discharge pipe 48, The treated liquid in the oil / water separation chamber R3 is also returned to the storage tank 40 through the treatment liquid outlet pipe 23 and the treatment liquid return pipe 44. As a result, the liquid level of the treated liquid in the oil / water separation chamber R3 also decreases,
When this liquid level reaches the lower end of the processing liquid outlet pipe 23, the bubbling air is supplied to the processing liquid outlet pipe 23 and the processing liquid return pipe 44.
Will also be released from. By this bubbling, the flow resistance of the liquid to be treated passing through the oil adsorbent G is reduced, and the oil / water separation treatment capacity is restored.

After this bubbling has been performed for a predetermined time T4, the controller 55 closes the electromagnetic valves SV4 and SV2 (step 217) to stop the bubbling, and returns the control operation to step 101. Similar to the above-described embodiment, if the flow resistance of the oil adsorbent G is sufficiently reduced by bubbling and the pressure switch PS2 is opened, the oil / water separation operation of step 104 is restarted, and if not, bubbling is repeated.

In the above-described embodiment and modification, the bubbling and the back washing are automatically performed by the control device 55. However, in the present invention, an operator pressure gauge PM2,
It is also possible to manually perform bubbling or backwashing based on the display of PM1 (or a means for measuring the cumulative value of the oil-water separation operation time after the end of the previous bubbling).

[0048]

As described above, according to the present invention, when a large amount of oil remains adsorbed on the oil adsorbent and the resistance to the flow of the liquid to be treated increases, bubbles are generated from the bubbling nozzle. By releasing, the oil adsorbed on the surface of the oil adsorbent is peeled off and rises along with the bubbles to be removed, whereby the resistance to the flow of the liquid to be treated is reduced and the oil-water separation treatment capacity is restored. Therefore, this oil-water separator can be used for a long period of time without taking out and replacing the oil adsorbent. Further, since the oil / water separation tank is composed of the upper tank member and the lower tank member that are detachably connected to each other, the oil / water separation tank can be easily disassembled and inspected.

According to the lower tank member, the processing liquid introducing pipe is provided so as to be oriented along the inner wall surface of the lower tank member so as to generate a vortex flow around the vertical central axis. Due to the vortex generated inside, the oil droplets having a smaller specific gravity than the liquid to be treated are gathered in the center and prevented from adhering to the inner wall surface of the lower tank member, so that the separation efficiency of the oil drops in the liquid to be treated is improved.

According to the invention, the bubbling nozzle is branched into two horizontal tip portions along the inner wall surface of the lower tank member, and a plurality of air holes are formed at each tip portion in the longitudinal direction. The air bubbles released from each air hole are raised almost evenly in the circumferential direction inside the lower tank member, and the oil-water separation treatment capacity of a large number of oil adsorbents is recovered evenly. Recovery is performed efficiently.

[Brief description of drawings]

FIG. 1 is a system diagram showing an overall configuration of an oil / water separator according to the present invention.

FIG. 2 is a partially cutaway plan view showing the structure of an embodiment of an oil / water separator according to the present invention.

3 is a partially cutaway left side view of the embodiment shown in FIG. 2. FIG.

FIG. 4 is a vertical cross-sectional view showing the structure of the oil-water separation tank of the embodiment shown in FIG.

5 is a sectional view taken along line 5-5 of FIG.

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

FIG. 7 is a flow chart illustrating the operation of an embodiment of the oil-water separator according to the present invention.

FIG. 8 is a flowchart illustrating a modified example of the operation of the embodiment of the oil-water separator shown in FIG. 7.

[Explanation of symbols]

20 ... Oil-water separation tank, 21 ... Upper tank member, 23 ...
Treatment liquid outlet pipe, 25 ... Lower tank member, 26 ... Treatment liquid introduction pipe, 30 ... Permeation plate (upper transmission plate), 38 ... Bubbling nozzles 38, 38b ... Tip portion, 39 ... Air hole, G ... Oil adsorbent.

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) B24B 55/12 B24B 55/12 C02F 1/28 C02F 1/28 N ZAB ZABT F term (reference) 3C011 EE08 3C047 FF00 GG17 4D024 AA04 AB06 BA17 BB01 BC04 CA02 CA07 DA06 DA07 DB08

Claims (3)

[Claims] 1. An oil droplet in a liquid to be treated, which is mainly composed of water and an oil droplet dispersed therein, is separated from water by adsorbing it on a lipophilic oil adsorbent in an oil / water separation tank. In the oil-water separation device, the oil-water separation tank includes an upper tank member and a lower tank member that are detachably connected, and the upper tank member is partitioned by a permeable plate through which liquid can pass. Inside the lower tank member, a processing liquid outlet pipe for accommodating the oil adsorbent in a lower part below the permeation plate and taking out a processed liquid in which oil droplets are separated is provided above the permeation plate. An oil / water separation device comprising a treatment liquid introducing pipe for introducing a treatment liquid and a bubbling nozzle for discharging bubbles. 2. The oil-water separation device according to claim 1, wherein the treatment liquid introducing pipe extends along the inner wall surface of the lower tank member so as to generate a vortex flow around a vertical central axis in the lower tank member. An oil / water separator characterized by being provided in the direction indicated by the arrow. 3. The oil-water separator according to claim 1 or 2, wherein the bubbling nozzle branches into two horizontal end portions along the inner wall surface of the lower tank member, and each of the end portions is branched. An oil-water separator, wherein a plurality of air holes are formed along the longitudinal direction.