JP2002166151A - Minute foam supply method and minute foam supply apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a minute foam supply technology capable of efficiently supplying a large quantity of minute foams to an object liquid. SOLUTION: This minute foam supply apparatus 10 comprises a fluid supply apparatus 11, a form generating apparatus 12 and a suction part 13 to be immersed in an objective liquid L, a pressure sending pipe 15 joining the fluid supply apparatus 11 and the foam generating apparatus 12, and a suction pipe 17 joining the fluid supply apparatus 11 and the suction part 13. The fluid supply apparatus 11 comprises a liquid pump 21 for sending the objective liquid L sucked through the suction part 13 to the foam generating apparatus 12 through the pressure sending pipe 15 and an air mixing apparatus 32 for mixing air in the objective liquid L sent to the foam generating apparatus 12 by pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for supplying microbubbles into a liquid which can be used in various fields including cleaning and activating water or other liquids.

[0002]

2. Description of the Related Art Conventionally, it has been known that various effects are produced by dissolving a bubbled gas into a liquid, and it has been applied in various industrial fields such as plant cultivation, seafood cultivation, and wastewater treatment. . In this case, it has been found that as a means for dissolving more of the bubbled gas in the liquid, it is effective to reduce the bubble diameter to increase the surface area of the entire bubble and increase the gas-liquid contact area. .

Techniques for dissolving bubbled gas in a liquid include a method using a diffuser tube, a method in which air is injected into water by an ejector, and a method in which a rotating body with blades is rotated near the water surface to stir the water. There are various methods such as a stirring and mixing method for generating bubbles, a method for generating bubbles in water by depressurizing air-dissolved pressurized water, and a method for generating bubbles using ultrasonic waves.

[0004] In the diffuser system, bubbles are generated by discharging pressurized air sent from a compressor or the like into a liquid through micropores. However, the air in the pressurized state expands in volume upon discharge. It is difficult to generate fine bubbles having an outer diameter of several tens of microns. In addition, when actually used, clogging of micropores is likely to occur in a relatively short period of time, so that frequent maintenance is required, and operation costs increase.

[0005] In the case of the stirring and mixing system, it is difficult in principle to effectively generate fine bubbles, and the power cost for constantly rotating the rotating body with a large load on the blade is large. In addition, the decompression method, the ejector method, and the ultrasonic method of the air-dissolved pressurized water require large-scale equipment and facilities, and are expensive, so that it is difficult to introduce them.

Japanese Patent Application Laid-Open No. 2000-4747 discloses a revolving microbubble generator 90 as shown in FIG. This revolving microbubble generator 90 is
A container body 91 having an inverted conical space 92, a liquid inlet 93 formed in a part of the inner peripheral surface 91a of the container body 91 in a tangential direction thereof, and a gas inlet formed at an upper end of the container body 91. It comprises a hole 94 and a swirling fluid outlet 95 formed in the lower part of the container body 91.

[0007] By injecting a liquid into the container body 91 from the tangential direction of the inner circumferential surface 91a of the inner wall 91 of the container body 91, a vortex or a rotating flow is generated in the space 92, and the central portion thereof is made negative pressure. Air in the atmosphere is introduced into the container main body 91 from an end portion 96a such as a vinyl tube 96 connected to the gas introduction port 94 to generate fine bubbles.
That is, the liquid is introduced from the liquid introduction port 93, the air is self-primed from the gas introduction port 94 under a negative pressure, and fine bubbles are generated from the swirling fluid discharge port 95.

[0008]

Problems to be Solved by the Invention
Patent Document 1: Swirling type microbubble generator 90
In this method, fine air bubbles are generated by cutting the air introduced into the container body 91 from the gas inlet port 94 into small pieces such that the air is twisted by the shearing force of the rotating flow of the liquid. Therefore, in order to reduce the diameter of the generated bubble, it is necessary to reduce the outer diameter of the gas vortex tube 97 formed at the center of the rotating flow as much as possible. Must be as small as possible. For this reason, the actual inner diameter of the gas inlet 94 is about 1 mm, and the vinyl tube 9 connected to the gas inlet 94 is
The inside diameter of 6 is also about the same. Therefore, the amount of gas introduced into the container body 91 from the gas inlet 94 must be small, and it is difficult to supply a large amount of fine bubbles into the liquid.

In addition, the small-diameter vinyl tube 96 connected to the gas inlet port 94 tends to be clogged with dust near the open end 96a exposed to the outside air. This is inconvenient when actually used since salt in the air sucked into the tube adheres to the inner wall of the vinyl tube 96 and causes clogging in a relatively short period of time.

When the vinyl tube 96 or the gas inlet 94 is clogged with dust or salt, cavitation occurs near the center of the container due to the rotational flow generated in the container main body 91. When it comes into contact with the gas inlet 94 and the opening of the swirling fluid outlet 95 on the inner wall of the main body 91, so-called cavitation erosion occurs, and the periphery of the opening is damaged so as to gouge and the device 90 becomes unusable. May lead to.

Further, since the shear force due to the rotating flow generated in the container body 91 acts from the side of the gas vortex tube 97 also generated in the container body 91, the energy loss is large, the efficiency is low, and When the microbubble generating device 90 is disposed at a position deep in the liquid 98 to supply a pressurized gas, when the gas supply amount increases, the expansion pressure of the gas increases due to the shearing force of the rotating flow. A phenomenon occurs in which fine bubbles are not generated, and the gas is discharged as a large diameter gas mass. In order to prevent this, it is necessary to increase the rotation flow rate generated inside the container body 91 by increasing the size of the container body 91 and sending a large amount of liquid. It will be.

An object of the present invention is to provide a method for supplying a large amount of fine bubbles into a target liquid efficiently, a method for supplying the fine bubbles easily, and a workability. Excellent in durability and maintainability,
An object of the present invention is to provide a fine bubble supply device that can be used in a wide range of fields.

[0013]

According to a first aspect of the present invention, there is provided a method for supplying fine air bubbles, comprising: a cylindrical space in which a fluid can swirl;
A fluid introduction port arranged in a tangential direction of a peripheral surface of the cylindrical space for feeding a fluid into the cylindrical space, and arranged on an extension of a central axis of the cylindrical space for flowing out the fluid from the cylindrical space. A microbubble generator equipped with a fluid outlet is immersed in the liquid, the liquid and gas are fed from the fluid inlet into the cylindrical space, and a swirling flow is generated in the cylindrical space to generate fine bubbles. ,
It is characterized in that a fluid containing fine bubbles is discharged from the fluid outlet into the liquid.

According to this method, the gas and the liquid swirling in the cylindrical space move in the outer peripheral direction by the centrifugal force acting on the liquid due to the difference in specific gravity, and the centripetal force acts on the gas. It moves toward the central axis of the rotating flow. At this time, the gas is sheared and refined by the liquid moving in the opposite direction, is accumulated near the center of the swirling flow while being mixed with gas and liquid, and is discharged from the fluid outlet as a fluid containing fine bubbles. That is, the shearing force of the rotational flow of the liquid acts strongly on the gas from the vertical and horizontal directions, and a large amount of fine bubbles can be efficiently supplied into the target liquid.

Here, when the gas-liquid mixed fluid is fed from the fluid inlet into the cylindrical space, the liquid and the gas separately fed from the liquid pump and the gas pump are mixed, and the liquid and the gas are mixed through the fluid inlet. A method of feeding the liquid into the cylindrical space, or mixing the gas into the liquid through the gas mixing means provided in the flow path of the liquid supplied from the liquid pump, and from the fluid inlet to the cylindrical space. It is possible to adopt a method of feeding. In this case, a decompression device called an aspirator can be used as the gas mixing means. If the aspirator is attached in the middle of the liquid supply pipe connecting the liquid pump and the fluid introduction port, the atmosphere can be removed via the aspirator. The air sucked from inside can be mixed with the liquid moving in the liquid supply pipe and supplied to the fluid introduction port.

In a second aspect of the method for supplying microbubbles according to the present invention, a tangential direction of a cylindrical space in which a fluid can be swirled and a peripheral surface of the cylindrical space for feeding a liquid into the cylindrical space is provided. Liquid inlet port, a gas inlet port provided in communication with the cylindrical space to supply gas into the cylindrical space, and a central axis of the cylindrical space to allow fluid to flow out of the cylindrical space. A microbubble generator having a fluid outlet arranged on an extension line is immersed in the liquid, and the liquid is fed from the liquid inlet into the cylindrical space and the gas is introduced from the gas inlet into the cylindrical space. The method is characterized in that the liquid is fed to generate a swirling flow in the cylindrical space to generate fine bubbles, and the fluid containing the fine bubbles is discharged from the fluid outlet into the liquid.

This second method is similar to the first method,
Due to the difference in specific gravity, the gas and liquid swirling in the cylindrical space move centrifugally to the liquid and move toward the outer circumference, and the gas applies centripetal force to move toward the center axis of the rotating flow. The gas is sheared and refined by the liquid moving in the opposite direction, is accumulated near the center of the swirling flow while being mixed with gas-liquid, and is discharged from the fluid outlet as a fluid containing fine bubbles, so a large amount of fine bubbles Can be efficiently supplied into the target liquid.

A first device of the microbubble generating device according to the present invention is arranged in a tangential direction of a cylindrical space in which a fluid can swirl and a peripheral surface of the cylindrical space for supplying the fluid into the cylindrical space. A microbubble generator having a fluid inlet port, a fluid outlet port disposed on the extension of the central axis of the cylindrical space to allow fluid to flow out of the cylindrical space, and a cylinder via the fluid inlet port. And a liquid supply means and a gas supply means for supplying a liquid and a gas into the space.

In such a configuration, when a liquid and a gas are mixed and supplied from the liquid supply means and the gas supply means to the fine bubble generator via the fluid inlet, the gas is introduced into the cylindrical space. The swirling flow of the liquid is generated, and the gas-liquid swirling in the cylindrical space moves in the outer peripheral direction due to the centrifugal force acting on the liquid due to the difference in specific gravity, and the centrifugal force acts on the gas, and the rotational flow center axis Move in the direction. At this time, the shearing force acts on the gas moving in the liquid in the direction of the center axis of the rotating flow due to the centrifugal force and the centripetal force opposing each other, and the gas is divided and finely divided. Shear acts due to the dynamic pressure energy of the rotating flow and is further miniaturized while being accumulated at the center of the rotating flow, and is discharged as a fluid containing fine bubbles from the fluid outlet. That is, since the shearing force of the rotational flow of the liquid acts on the gas from the vertical and horizontal directions with respect to the moving direction of the gas, a large amount of fine bubbles can be efficiently supplied into the target liquid.

As described above, a large amount of fine bubbles can be supplied to the fine bubble generator immersed in the target liquid simply by mixing and feeding the liquid and gas by the liquid supply means and the gas supply means. And generate and release fine bubbles using the centrifugal force, centripetal force and shearing action of the swirling flow.
Excellent workability, durability and maintainability, and can be used in a wide range of fields. In addition, by supplying a gas-liquid mixed fluid in which a gas and a liquid are mixed in advance to a fine bubble generator, the contact time between the gas and the liquid can be extended, and the liquid being supplied can be supplied. Since the gas solubility in the liquid is increased by being pressurized by the pressure, the gas can be dissolved in the liquid even in the feeding process.

Here, when the gas-liquid mixed fluid is fed into the cylindrical space from the fluid inlet, the liquid and the gas separately fed from the liquid pump and the gas pump are mixed as described above. From the fluid inlet through the fluid inlet, or by mixing gas into the liquid through a gas inlet that communicates with the flow path of the liquid fed by the liquid pump. It is possible to adopt a method of feeding into a cylindrical space. In this case, as the gas mixing means, a decompression device called an aspirator can be suitably used.

A second device of the fine bubble supply device according to the present invention is arranged in a tangential direction of a cylindrical space in which a fluid can be swirled and a peripheral surface of the cylindrical space for supplying a liquid into the cylindrical space. Liquid inlet, a gas inlet provided in communication with the cylindrical space to supply gas into the cylindrical space, and an extension of the central axis of the cylindrical space to allow fluid to flow out of the cylindrical space. A microbubble generator having a fluid outlet disposed in the liquid supply means for supplying liquid into the cylindrical space via the liquid inlet, and a cylindrical space via the gas inlet. And gas supply means for supplying gas into the inside.

With such a configuration, when liquid and gas are supplied from the liquid supply means and the gas supply means into the fine bubble generator via the liquid introduction port and the gas introduction port, respectively, As with the first microbubble generator, a fluid containing microbubbles is discharged from the fluid outlet.

Further, by separately supplying the gas and the liquid to the microbubble generator, the microbubble generator is disposed at a position where a relatively high liquid pressure is received, for example, at a position deeper than a water depth of 10 m. Even in this case, since the gas can be sent to the bubble generator in a state as it is, fine bubbles can be stably generated regardless of the level of the liquid pressure.

Here, by arranging a plurality of fluid inlets, liquid inlets, and gas inlets at positions symmetrical with respect to a central cross section in the central axis direction of the cylindrical space, a gas-liquid mixed fluid,
A large amount of liquid or gas can be fed into the cylindrical space from multiple locations to generate a stable swirling flow in the cylindrical space, so that fine bubbles are more efficiently and stably supplied. Will be able to In addition, even when the cylindrical space is increased in size in the axial direction, the stability of the swirling flow can be secured, and the efficiency of supplying fine bubbles can be further improved by increasing the size of the fine bubble generator.

Further, by arranging the fluid outlets of the microbubble generator on both end faces in the direction of the central axis of the cylindrical space, a revolving microbubble generator disclosed in Japanese Patent Application Laid-Open No. 2000-4747 is disclosed. Compared to such a one-sided opening method,
Energy loss due to friction between the swirling flow in the cylindrical space and the inner wall surface of the end of the cylindrical space is reduced, and a fluid containing fine bubbles can be discharged from a plurality of fluid outlets. Supply efficiency is further improved. In addition, since cavitation generated along the central axis of the cylindrical space due to the swirling flow does not contact the inner wall surface of the cylindrical space, cavitation erosion does not occur, and the durability of the entire device is improved, Maintenance can be simplified.

By providing a smaller diameter portion than the fluid introduction port and the liquid introduction port at the opening end of the fluid introduction port and the liquid introduction port facing the cylindrical space, the fluid is fed toward the cylindrical space. Fluids and liquids are squeezed at the reduced diameter portion and are sped up into the cylindrical space at high speed and high pressure, so that a high-speed swirling flow is formed in the cylindrical space, and fine bubbles can be supplied more efficiently. it can. Further, since a fluid supply pipe and a liquid supply pipe having a relatively large inner diameter can be used as a means for supplying a fluid and a liquid to the fluid introduction port and the liquid introduction port, energy loss in a supply process is reduced. Thus, the efficiency of supplying fine bubbles can be further improved.

[0028]

FIG. 1 is an overall configuration diagram showing a fine bubble supply device according to a first embodiment of the present invention. FIG. 2 is a front view of a bubble generator constituting the fine bubble supply device shown in FIG. FIG. 3 is a side view of the bubble generator, and FIG.
FIG. 5 is a cross-sectional view taken along line A-B in FIG. 3.

As shown in FIG. 1, a fine bubble supply device 10 according to the present embodiment includes a fluid supply device 11 disposed on the ground.
, A bubble generator 12 and a suction unit 13 to be injected into the target liquid L, a pressure feed pipe 15 connecting the fluid supply device 11 and the bubble generator 12, a fluid supply device 11 and a suction unit 1
3 and the like. The fluid supply device 11 includes a liquid pump 21 that pumps the target liquid L sucked through the suction part 13 and the suction pipe 17 to the bubble generator 12 through the pressure feeding pipe 15 and generates air sucked from the atmosphere into bubbles. And a gas mixing device 23 that mixes into the target liquid L that is pressure-fed to the vessel 12.

The gas mixing device 23 includes an air compressor 2
4. The air pressure adjusting valve 25 and the pressure gauge 26 are connected to each other through an air supply pipe 27, and the air supply pipe 27 is connected to the pressure supply pipe 15. The air pressure adjusting valve 25 is an air pressure adjusting means for adjusting the supply amount of the compressed air generated by the compressor 24, and functions as a bubble size adjusting means for changing the outer diameter of the fine bubbles generated in the bubble generator 12.

Liquid pump 21 and air compressor 2
4, the liquid pump 21 sucks the target liquid L through the suction part 13 and the suction pipe 17 and sends the sucked target liquid L to the pressure feed pipe 15, and at the same time, the air compressor 24 draws air sucked from the atmosphere. Is fed into the target liquid L moving in the pressure feeding pipe 15 via the air feeding pipe 27, so that a mixed fluid of the target liquid L and air is sent to the bubble generator 12 via the pressure feeding pipe 15. The mixed fluid of the target liquid L and air sent to the bubble generator 12 becomes a mixed fluid of the fine bubbles and the target liquid L through a swirling process described later in the bubble generator 12 to become the mixed fluid of the bubble generator. 12 and diffuses into the target liquid L, thereby causing fine bubbles to form in the target liquid L.
It is continuously fed into.

As shown in FIGS. 2 to 4, the bubble generator 12 constituting the fine bubble supply device 10 is formed of a synthetic resin or the like, and has a rectangular parallelepiped outer shape. And a lid portion 16 integrally formed at both ends of the cylindrical member, and has a cylindrical space S in which liquid and gas can swirl together.

The peripheral wall portion 14 is provided with two fluid introduction ports 18 for introducing a mixed fluid of liquid and air into the space S in communication with the cylindrical space S. These fluid introduction ports 18 are hollow cylindrical bodies 20 projecting outward from the peripheral wall portion 14.
And the fluid introduction port 18 communicates in the same direction as the tangential direction of the circumferential surface of the cylindrical space S. Further, the two fluid inlets 18 are provided in a cylindrical space S.
Are provided at symmetrical positions with respect to the central transverse section 19 having the axial length.

Fluid outlets 22 are provided at the center portions of the lids 16 at both ends of the bubble generator 12, that is, on the extension of the central axis XX of the cylindrical space S. These fluid outlets 22 are all circular, have the same opening area, and are provided symmetrically with respect to the center transverse section 19 of the space S. The fluid outlet 22 serves as a path for discharging the gas-liquid mixed fluid swirling in the bubble generator 12 together with the fine bubbles generated therein into the target liquid L outside. Then, the target liquid L mixed with fine bubbles discharged from the bubble generation unit 12 through the fluid outlet 22 immediately diffuses into the target liquid L around the bubble generator 12.

In the bubble generator 12, a gas-liquid mixed fluid is injected from the tangential direction of the peripheral surface of the cylindrical space S, and the liquid is swirled at a high speed to generate fine bubbles. It is not necessary to reduce the diameter of the fluid introduction port 18 in correspondence with the above. For example, the diameter may be set to about 1 cm. When the gas-liquid mixed fluid is injected from the fluid inlet 18, the size of the fine bubbles generated in the bubble generator 12 changes depending on the amount of air sent from the air compressor 24 to the pressure pipe 15. An air pressure adjusting valve 25 is provided as a means for changing continuously or selectively.

Here, the bubble generation mechanism in the bubble generator 12 will be described in detail with reference to FIGS. As shown in FIG. 5, the gas-liquid mixed fluid pumped into the bubble generator 12 from the fluid inlet 18 is a central axis connecting the centers of the fluid outlets 22 of the lids 16 at both ends, that is, the cylindrical space S. And a gas-liquid swirl flow 29 that swirls at a high speed around the central axis XX of the bubble generator 12 and the vicinity thereof, and the gas-liquid swirl flow 29 moves while swirling toward the intermediate portion of the bubble generator 12. Stream 30 and bubble generator 12
Swirling flow 31 moving while swirling toward both ends of
And shunted.

Each of the intermediate swirling flows 30 moves while swirling toward the central cross section 19 of the bubble generator 12.
The moving direction is reversed at the central transverse section 19 where these collide with each other, and moves toward the fluid outlet 22 near the central axis XX. After the reversal, the intermediate swirl 30 moving near the central axis XX merges with the end swirl 31 immediately before the fluid outlet 22 to form a swirl 32 and is discharged from the fluid outlet 22 to the outside. You.

As shown in FIGS. 6 and 7, the gas-liquid mixed fluid including the intermediate swirling flow 30 and the end swirling flow 31 which swirl at high speed in the bubble generator 12 is subjected to the central axis XX by centrifugal force. The swirling cavity 28, which is further compressed toward the inner wall side of the bubble generator 12 and becomes a negative pressure by the action of the centrifugal force, has a central axis XX
Occurs along the neighborhood. Then, the dissolved gas in the intermediate swirling flow 30 and the end swirling flow 31 becomes fine bubbles 33 in the swirling cavity 28 in the negative pressure state due to the boiling under reduced pressure, that is, the gasification phenomenon of the dissolved gas due to the reduced pressure. appear. The fine bubbles 33 are accompanied by the flows of the intermediate swirling flow 30 and the end swirling flow 31, and finally, accompanying the swirling flow 32,
From the fluid outlets 22 on both sides of the bubble generator 12, the target liquid L
Released inside.

When the gas-liquid mixed fluid in the bubble generator 12 is discharged from the cylindrical space S to the outside through the fluid outlet 22, a complicated operation occurs. In the space S near the fluid outlet 22, an internal pressure reducing portion 34 is generated by the interaction between the swirling flow 32 and the swirling cavity portion 28, and the external pressure reducing portion 35 is also provided near the fluid outlet 22 outside the space S. Are generated, and fine bubbles are also generated from these portions by the action of boiling under reduced pressure.

As shown in FIGS. 8 and 9, the gas-liquid mixed fluid circling at high speed in the bubble generator 12 has a centripetal force acting on the gas due to the difference in specific gravity of the gas-liquid, and the centrifugal force acting on the liquid. , The liquid moves to the outside of the swirl flow 32, and the gas moves to the center side of the swirl flow 32. At this time, the fluid inlet 18
The gas contained in the gas-liquid mixed fluid flowing into the bubble generator 12 from the air is turned into fine bubbles while being sheared by the action of the swirling flow to form swirling cavities 28 near the central axis XX of the swirling flow 32.
And moves toward the distal end side 36 of the swirling cavity 28 with the surrounding fluid moving toward the fluid outlet 22 while swirling at high speed.

On the tip side 36 of the swirling cavity 28, a liquid surface 37 around the swirling cavity 28, which has the same boundary as the swirling cavity 28 to be discharged from the bubble generator 12,
The liquid level 38 at the leading end of the liquid L outside the bubble generator 12 that is about to be drawn into the swirl cavity 28 by the negative pressure of the swirl cavity 28 depends on the viscous force of the water and the negative pressure of the swirl cavity 28. Due to the action of the suction force, the swirling cavity portion 28 is in close contact with the swirling cavity portion 28 as if it were plugged. Therefore, when the air bubbles pass through the contact portion, they are crushed by the compressive force of the liquid surface 37 and the liquid surface 38.

The swirling speed of the swirling flow 32 is higher at the fluid outlet 22 having an inner diameter smaller than the space S in the bubble generator 12, and near the boundary between the bubble generator 12 and the fluid outlet 22, the swirling speed difference Shear force is generated. At this time, the bubbles become the fine bubbles 33 which are further divided by the above-mentioned compressive force and shear force. In addition, the fine bubble supply device 1
Swirling cavity 2 generated in bubble generator 12 during use
8 does not come into contact with the inner wall surface of the bubble generator 12 or the inner peripheral surface of the fluid outlet 22, so that cavitation erosion does not occur, the durability of the entire apparatus is excellent, and maintenance can be simplified. it can.

At this time, if the gas mixing rate in the gas-liquid mixed fluid flowing from the fluid inlet 18 is increased, the swirling cavity 2
8 is weakened, the adhesive force between the liquid surface 37 and the liquid surface 38 is reduced, and the compressive force against the bubbles is also reduced. Therefore, the outer diameter of the fine bubbles discharged from the bubble generator 12 increases, and conversely, the gas If the mixing ratio is reduced, the outer diameter of the fine bubbles becomes smaller.

As described above, by increasing or decreasing the gas mixing rate in the gas-liquid mixed fluid flowing into the bubble generator 12,
The outer diameter of the generated fine bubbles can be increased or decreased. Specifically, by adjusting the above-described air pressure adjusting valve 25 to change the amount of compressed air supplied to the pressure feeding pipe 15 within a range where the pressure in the bubble generator 12 does not become a positive pressure,
The outer diameter size of the generated fine bubbles can be finely adjusted. In the case of the fine bubble supply device 10, since the gas-liquid mixed fluid is supplied to the bubble generator 12 via the single pressure supply tube 15, a long air supply tube or the like is not required. Piping and handling are easy, and there is no risk of clogging the air supply pipe.

By using the microbubble supply device 10, microbubbles are continuously and stably supplied into the target liquid L to increase the amount of dissolved oxygen, purify water, promote the growth of cultured animals and plants, By realizing activation and the like, and supplying a large amount of gas-liquid mixed fluid from the fluid outlet 22 into the target liquid L, a circulating flow can be generated in the closed water area.

The application of the microbubble supply device 10 of the present embodiment is not particularly limited. For example, microbubble is supplied to a target liquid such as a liquid for growing animals and plants, water to be treated before water purification, and dam lake water. And can be used in various fields.

The space S in the bubble generating section 12 is not limited to the cylindrical shape, but may be a polygon such as a square cylinder, a pentagonal cylinder, a hexagonal cylinder, etc. It may be cylindrical. In the case of a polygonal cylinder, high-frequency sound waves or ultrasonic waves are generated by vibration generated by collision with a wall surface when a mixed fluid of liquid and gas turns at high speed in space,
Since the action of decomposing substances contained in the liquid for supplying fine bubbles is also generated, it is also effective in detoxifying harmful substances.

FIG. 10 is a view showing another embodiment of the bubble generator. 10, members having the same functions as those of the bubble generator 12 of FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted.

In the bubble generator 12a shown in FIG. 10, a reduced diameter portion 18a having a smaller diameter than the fluid introduction port 18 is provided at the open end of the fluid introduction port 18 facing the cylindrical space S. The gas-liquid mixed fluid sent toward the space S is increased in speed and pressure by being constricted by the reduced diameter portion 18a, and is ejected into the space S, thereby forming a high-speed gas-liquid swirling flow 29 in the space S. Therefore, fine bubbles can be generated more efficiently. Further, since the pressure feed pipe 15 having a relatively large inner diameter can be used as a means for feeding the gas-liquid mixed fluid to the fluid inlet port 18, energy loss in the feed process is small, and the efficiency of supplying fine bubbles is greatly improved. I do.

FIG. 11 is an overall configuration diagram showing a fine bubble supply device according to a second embodiment of the present invention. In the figure, members having the same functions as those of the fine bubble supply device of FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. In the present embodiment, an aspirator 3, which is one of the decompression devices, is provided in the middle of a pressure feed pipe 15 connecting the liquid pump 21 and the bubble generator 12.
9 is attached. Pressure pump 1 from liquid pump 21
When the liquid L fed through 5 passes through the aspirator 39, air self-absorbed from the atmosphere via the aspirator 39 is mixed into the liquid L, and becomes a gas-liquid mixed fluid to generate bubbles. The fluid is supplied to the fluid inlet 18 of the vessel 12. Since the intake amount adjusting valve 40 is attached to the intake port of the aspirator 39, the amount of air mixed into the liquid L can be adjusted. Since the aspirator 39 is used, an air compressor, an air supply pipe, and the like are not required, so that the device configuration can be simplified and the manufacturing cost can be reduced.

FIG. 12 is a perspective view showing a bubble generator constituting a fine bubble supply device according to a third embodiment of the present invention.
3 is a sectional view taken along line CC in FIG. 12, and FIG. 14 is a sectional view taken along line DD in FIG. In these figures, the first
Members having the same functions as those of the bubble generator of the embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The bubble generator 50 constituting the fine bubble supply device of the present embodiment has a rectangular parallelepiped outer shape similar to the bubble generator 12 of the first embodiment, and has a peripheral wall portion 14 and both ends of the peripheral wall portion 14. It has a cylindrical space S in which the liquid and the gas can be swirled together.

The peripheral wall 14 has two liquid inlets 51 for introducing a liquid into the space S and two gas inlets 52 for introducing a gas into the space S, respectively.
The communication is provided. The liquid inlet 51 is located on the peripheral wall 1
4 is joined to a hollow cylinder 53, and the gas inlet 52 is
4 is formed by joining a hollow cylindrical body 54. The liquid inlet 51 is provided in the same direction as the tangential direction of the circumferential surface of the cylindrical space S, and the gas inlet 52 is provided in a direction orthogonal to the central axis XX of the space S. Further, the two liquid introduction ports 51 and the gas introduction ports 52 are respectively provided at symmetrical positions with respect to the central transverse section 19 of the axial length of the cylindrical space S.

When the liquid is sent from the liquid inlet 51 into the space S to generate a high-speed swirling flow in the space S, the negative pressure generated in the space S causes the space S via the gas inlet 52 to be sucked.
Air flows into the inside and a high-speed gas-liquid swirl flow is generated,
Similar to the bubble generator 12 described above, a large amount of fine bubbles are generated in the space S, and the fluid containing the fine bubbles is supplied to the fluid outlet 22.
And diffuses into the liquid.

As described above, the gas is automatically sucked into the space S via the gas introduction port 52 only by feeding the liquid from the liquid introduction port 51 into the space S. This eliminates the need for a pressure feed pipe or a gas supply system, thereby simplifying the device configuration and reducing manufacturing costs. Further, similar to the bubble generator 12, fine bubbles are generated only by the swirling motion of the gas-liquid mixed fluid in the space S, so that it is not necessary to reduce the opening area of the fluid outlet 22 or the inner diameter of the gas inlet 52. Clogging due to dust and the like is unlikely to occur.

[Example 1] The microbubble supply device 10 described as the first embodiment is connected to a fish farm (area of 10,000
0 m ² , water depth 6 m, water tank water depth 5.5 m). The bubble generator 12 is arranged in the water in the water tank, and the liquid pump 21 of the fluid supply device 11 (AC100V, 200W)
The bubble generator 12 and the bubble generator 12 are connected by a pressure feed pipe 15 made of vinyl chloride, and the suction unit 13 connected to the liquid pump 21 via the suction pipe 17 is disposed in water.

The liquid pump 21 is operated and the suction unit 13
At the same time as sending water sucked from
Compressor 24 (AC100, 750W, discharge pressure 8k
gf / cm ² ) and pressurized air supplied from
The air bubbles are generated by the bubble generator 12 by adjusting the pressure at 5 and feeding into the pressure feed pipe 15 via the air supply pipe 27. After a lapse of a predetermined time, the amount of dissolved oxygen in the water was measured. As a result, the value was significantly increased, and it was confirmed that the amount of dissolved oxygen in the entire water tank increased in a relatively short time.

Example 2 The bubble generator 50 described as the third embodiment was immersed in a biotope pond (area 20 m ² , water depth 0.6 m) in a water stop area, and only the liquid was converted to liquid using a liquid pump. Fine bubbles were generated by the bubble generator 50 by sending the air into the space S from the gas inlet 52 through the gas supply tube while sending the air into the space S from the inlet 51.

In the biotope pond, wasabi, mizubashio,
Simultaneously observing aquatic plants such as chromo, hiramo, Hozakinofusamo and fish and other aquatic insects such as yamame, char, charr, crucian carp, firefly, and aquatic insects. As a result, it was possible to raise the inhabitable temperature limit by several degrees or more. Similarly, it has become possible to breed fish in the watershed and stillwater areas at the same time.

Further, it was confirmed that even after a long period of time after the supply of the fine bubbles by the bubble generator 50 was started, there was no clogging of the device and the device could be continuously used without maintenance. Furthermore, since the dissolved oxygen supply efficiency can be improved only by a liquid pump having relatively small power consumption, the maintenance work can be simplified and the equipment cost can be reduced.

[0061]

According to the present invention, the following effects can be obtained.

(1) A cylindrical space in which a fluid can swirl, a fluid inlet port arranged tangentially to the peripheral surface of the cylindrical space, and a fluid outlet port arranged on an extension of the central axis of the cylindrical space. A microbubble generator equipped with a liquid is immersed in the liquid, and the liquid and gas are fed from the fluid inlet into the cylindrical space to generate microbubbles in the cylindrical space. By discharging the fluid containing bubbles, a large amount of fine bubbles can be efficiently supplied into the target liquid while dissolving the gas into the liquid in the feeding process.

(2) A cylindrical space in which a fluid can be swirled, a liquid inlet arranged in a tangential direction on the peripheral surface of the cylindrical space, a gas inlet provided in communication with the cylindrical space, A microbubble generator having a fluid outlet arranged on an extension of the central axis of the liquid space is immersed in the liquid, and the liquid is supplied from the liquid inlet into the cylindrical space and the gas is introduced from the gas inlet to the cylinder. By supplying gas into the cylindrical space and generating microbubbles in the cylindrical space, and discharging the fluid mixed with microbubbles into the liquid from the fluid outlet, the hydraulic pressure applied to the microbubble generator can be reduced. A large amount of microbubbles can be efficiently supplied into the target liquid without being affected.

(3) A cylindrical space in which a fluid can swirl, a fluid inlet port arranged in a tangential direction of the peripheral surface of the cylindrical space, and a fluid outlet port arranged on an extension of the central axis of the cylindrical space. And a liquid supply means and a gas supply means for supplying a gas-liquid mixed fluid into the cylindrical space via the fluid introduction port, so that the supply process A large amount of fine bubbles can be efficiently supplied into the target liquid while dissolving the gas in the liquid, and the workability, durability, and maintainability are excellent and can be used in a wide range of fields.

(4) A cylindrical space in which a fluid can be swirled, a liquid introduction port arranged tangentially to the peripheral surface of the cylindrical space, a gas introduction port provided in communication with the cylindrical space, A microbubble generator having a fluid outlet disposed on an extension of the central axis of the cylindrical space, a liquid supply means for supplying liquid into the cylindrical space via the liquid inlet, and a gas inlet. By using gas supply means for supplying gas into the cylindrical space via the mouth, a large amount of fine bubbles can be contained in the target liquid regardless of the level of the hydraulic pressure applied to the fine bubble generator. It can be supplied efficiently, is excellent in workability, durability and maintainability, and can be used in a wide range of fields.

(5) By arranging a plurality of fluid inlets, liquid inlets, and gas inlets at positions symmetrical with respect to a central cross section in the central axis direction of the cylindrical space, fine bubbles can be more efficiently and efficiently formed. It can be supplied stably.
In addition, even when the cylindrical space is increased in size in the axial direction, the stability of the swirling flow can be secured, and the efficiency of supplying fine bubbles can be further improved by increasing the size of the fine bubble generator.

(6) By arranging the fluid outlets of the microbubble generator on both end faces in the central axis direction of the cylindrical space, the friction between the swirling flow in the cylindrical space and the inner wall surface at the end of the cylindrical space is obtained. This reduces the energy loss due to the above, and makes it possible to discharge the fluid containing the fine bubbles from the plurality of fluid outlets, so that the supply efficiency of the fine bubbles is further improved. In addition, since cavitation generated along the central axis of the cylindrical space does not contact the inner wall surface of the cylindrical space, cavitation erosion does not occur, durability of the entire apparatus is improved, and maintenance can be simplified. it can.

(7) A high-speed swirling flow is formed in the cylindrical space by providing a smaller diameter portion than the fluid inlet and the liquid inlet at the opening end of the fluid inlet and the liquid inlet facing the cylindrical space. Are formed, so that fine bubbles can be supplied more efficiently. Further, since a fluid supply pipe and a liquid supply pipe having a relatively large inner diameter can be used, energy loss in the supply process can be reduced, and the efficiency of supplying fine bubbles can be further improved.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram illustrating a fine bubble supply device according to a first embodiment.

FIG. 2 is a front view of a bubble generator included in the fine bubble supply device of FIG.

FIG. 3 is a side view of the bubble generator of FIG. 2;

FIG. 4 is a sectional view taken along line AA in FIG. 3;

FIG. 5 is a sectional view taken along line BB in FIG. 3;

FIG. 6 is a diagram showing a state of generation of a swirling flow in the bubble generator.

FIG. 7 is a diagram showing a state of generation of fine bubbles in a bubble generator.

FIG. 8 is a diagram showing a state of generation of fine bubbles in a bubble generator.

FIG. 9 is a partially enlarged view of the vicinity of a fluid outlet in FIG. 6;

FIG. 10 is a sectional view showing another embodiment of the bubble generator.

FIG. 11 is an overall configuration diagram illustrating a fine bubble supply device according to a second embodiment.

FIG. 12 is a perspective view showing a bubble generator included in the fine bubble generator according to the third embodiment.

13 is a sectional view taken along line CC in FIG.

14 is a sectional view taken along line DD in FIG.

FIG. 15 is a view showing a structure of a conventional bubble supply device.

[Explanation of symbols]

 L Target liquid S Space 10 Micro-bubble supply device 12, 12a, 40 Bubble generator 13 Suction part 14 Peripheral wall part 15 Pumping pipe 16 Cover part 17 Suction pipe 18 Fluid introduction port 18a Reduced diameter part 19 Center transverse cross section of space 20, 53 , 54 hollow cylinder 21 liquid pump 22 fluid outlet 23 gas mixing device 24 air compressor 25 air pressure regulating valve 26 pressure gauge 27 air supply pipe 28 swirl cavity 29 gas-liquid swirl flow 30 intermediate swirl flow 31 end swirl flow 32 swirl Flow 33 Microbubbles 34 Internal decompression unit 35 External decompression unit 36 Tip side of swirl cavity 37, 38 Liquid level 39 Aspirator 40 Intake air amount adjustment valve 51 Liquid inlet 52 Gas inlet

Claims (9)

[Claims] 1. A cylindrical space in which a fluid can be swirled, a fluid inlet disposed in a tangential direction of a peripheral surface of the cylindrical space for supplying the fluid into the cylindrical space, and the cylindrical space. A microbubble generator having a fluid outlet provided on an extension of the central axis of the cylindrical space to allow the fluid to flow out of the liquid, and immersing the liquid into the cylindrical space from the fluid inlet. And supplying gas and generating a swirling flow in the cylindrical space to generate fine bubbles, and discharging the fluid containing the fine bubbles into the liquid from the fluid outlet. . 2. A cylindrical space in which a fluid can be swirled, a liquid introduction port disposed in a tangential direction of a peripheral surface of the cylindrical space for feeding the liquid into the cylindrical space, and the cylindrical space. A gas inlet provided in communication with the cylindrical space for supplying gas into the inside, and a fluid outlet provided on an extension of a central axis of the cylindrical space for allowing a fluid to flow out of the cylindrical space. Immersing the microbubble generator with liquid in the liquid, supplying the liquid from the liquid inlet into the cylindrical space and supplying the gas from the gas inlet into the cylindrical space, A method for supplying fine bubbles, wherein a swirling flow is generated in a cylindrical space to generate fine bubbles, and a fluid containing fine bubbles is discharged from the fluid outlet into the liquid. 3. A cylindrical space in which a fluid can swirl, a fluid inlet arranged in a tangential direction of a peripheral surface of the cylindrical space for supplying the fluid into the cylindrical space, and the cylindrical space. A microbubble generator having a fluid outlet provided on the extension of the central axis of the cylindrical space for allowing fluid to flow out, and liquid and gas flowing into the cylindrical space via the fluid inlet. A fine bubble supply device comprising a liquid supply means and a gas supply means for supplying liquid. 4. A cylindrical space in which a fluid can be swirled, a liquid inlet disposed in a tangential direction of a peripheral surface of the cylindrical space for feeding the liquid into the cylindrical space, and the cylindrical space. A gas inlet provided in communication with the cylindrical space for supplying gas into the inside, and a fluid outlet provided on an extension of a central axis of the cylindrical space for allowing a fluid to flow out of the cylindrical space. A microbubble generator comprising: a liquid supply means for supplying a liquid into the cylindrical space through the liquid inlet; and a gas into the cylindrical space through the gas inlet. And a gas supply means for supplying the gas. 5. The microbubble supply device according to claim 3, wherein a plurality of the fluid introduction ports are arranged at positions symmetrical with respect to a center transverse section in the central axis direction of the cylindrical space. 6. The microbubble supply device according to claim 4, wherein a plurality of the liquid inlets and the gas inlets are arranged at positions symmetrical with respect to a central cross section in the central axis direction of the cylindrical space. 7. The microbubble generating device according to claim 3, wherein the fluid outlets are arranged on both end faces in the central axis direction of the cylindrical space. 8. The microbubble generating device according to claim 3, wherein a reduced diameter portion having a smaller diameter than the fluid introduction port is provided at an opening end of the fluid introduction port facing the cylindrical space. 9. The microbubble generator according to claim 4, wherein a reduced diameter portion having a diameter smaller than that of the liquid inlet is provided at an opening end of the liquid inlet facing the cylindrical space.