JP2006314972A - Bubbles generating apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fine-bubbles generating apparatus which can cheaply produce a liquid containing a few of fine bubbles using a simple apparatus. <P>SOLUTION: The bubbles generating apparatus has an airtight vessel 1 for receiving the liquid 4, a gas introducer 2 for introducing a gas 3 into the airtight vessel 1 and dissolving the gas 3 in the liquid 4 by compressing the liquid 4, a discharging part 6 which is arranged in the airtight vessel 1 and has an outlet 7 for discharging the liquid 4 from the airtight vessel 1 outside, and a conduit pipe 60 which has the larger inner diameter than the opening diameter of the outlet 7 and is connected to the outlet 7. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a bubble generating device that generates bubbles, and more particularly to a bubble generating device that generates fine bubbles.

  It has been announced that fine bubbles or liquids containing fine bubbles have various effects, and application studies of fine bubbles have been conducted in a wide range of fields. The effects of the fine bubbles are: (1) the action of improving the dispersibility of suspended matters in water, (2) the action of improving the gas absorption efficiency of the liquid, (3) the oxidative decomposition action of the liquid containing the fine bubbles, (4) Inactivation of liquid viruses containing fine bubbles has been reported.

  These effects are obtained when the fine bubbles come into contact with the surface of the dispersion in the liquid, or the gas that has become fine bubbles reacts with the surface of the dispersion in the liquid. For this reason, it is important that the fine bubbles are dispersed in the liquid for a long time without suddenly rising and disappearing.

Various methods have been proposed for the production of fine bubbles. For example, Patent Document 1 discloses a microbubble generator using ultrasonic waves. Patent Document 2 discloses a fine bubble generator utilizing the principle of an aspirator. Patent Documents 3 and 4 disclose a microbubble generator using a swirling liquid flow.
JP 2003-334548 A JP 2002-191950 A JP 2000-447 A JP 2004-263152 A

  Many conventional microbubble generators are intended for industrial use and large-scale industrial fields such as fish farming. For this reason, the microbubble generator is generally large, and it is necessary to move a large amount of liquid in order to generate microbubbles.

  However, the effect of the fine bubbles described above is considered to be useful not only in the industrial field but also in use in general households and household appliances such as suppression of mold in washing machines and bathrooms. In order to obtain the effect of fine bubbles in such general household use and household equipment, it is considered sufficient to have a liquid containing fine bubbles of about several milliliters to several tens of milliliters.

  However, as described above, many conventional fine bubble generating devices are large. For this reason, even in order to generate a small amount of fine bubbles, it is necessary to move a large apparatus using a large amount of energy. This causes a problem that the initial investment cost and the operation cost become too large for use in general households.

  An object of the present invention is to solve such a conventional problem, and to provide a microbubble generator that can produce a liquid containing a small amount of microbubbles at low cost using a simple apparatus.

  The bubble generating device of the present invention includes an airtight container that stores a liquid, a gas introduction device that introduces gas into the airtight container and pressurizes the liquid to dissolve the gas in the liquid, and the airtight container. A discharge part having a discharge port for discharging the liquid from the hermetic container to the outside, and a conduit connected to the discharge port and having an inner diameter larger than the opening diameter of the discharge port With.

  In a preferred embodiment, the conduit has such a length that the liquid discharged from the discharge port stays in the conduit at a predetermined flow rate for 0.5 seconds or more.

  In a preferred embodiment, the length of the conduit is 50 mm or more.

  In a preferred embodiment, the discharge port has an opening diameter of 0.1 mm to 5 mm, and the conduit has an inner diameter of 0.5 mm to 10 mm.

  The bubble generating device of the present invention includes an airtight container that stores a liquid, a gas introduction device that introduces gas into the airtight container and pressurizes the liquid to dissolve the gas in the liquid, and the airtight container. From the discharge unit having a discharge port for discharging the liquid from the hermetic container to the outside, and the liquid discharged from the discharge port. A bubble separator for separating bubbles having a large diameter.

  In a preferred embodiment, the bubble separator includes a mesh having a predetermined opening, and bubbles having a diameter larger than the predetermined value are obtained when the liquid discharged from the discharge port passes through the mesh. Remove.

  In a preferred embodiment, the net has an opening having a fineness of 100 mesh or more.

  In a preferred embodiment, the bubble separator includes a conduit having an inlet, an outlet, and a bubble outlet, and the network is configured to flow the liquid between the inlet and the outlet of the conduit. The bubble discharge port is provided in the pipe line so that the bubbles separated by the net rise and reach the bubble discharge port.

  In a preferred embodiment, the apparatus further includes a conduit having an inner diameter larger than an inner diameter of the discharge port between the discharge port of the discharge unit and the introduction port of the bubble separator and connected to the discharge port.

  In a preferred embodiment, the conduit has such a length that the liquid discharged from the discharge port stays in the conduit at a predetermined flow rate for 0.5 seconds or more.

  In a preferred embodiment, the length of the conduit is 50 mm or more.

  In a preferred embodiment, the discharge port has an inner diameter of 0.1 mm to 5 mm, and the conduit has an inner diameter of 0.5 mm to 10 mm.

  In a preferred embodiment, the liquid is water or a hydrophilic solvent.

  In a preferred embodiment, the gas includes at least one of oxygen gas, ozone gas, nitrogen gas, carbon gas, hydrogen gas, air containing negative ions, and group 18 element gas.

  In certain preferred embodiments, the conduit is flexible.

  In a preferred embodiment, the apparatus further comprises an on-off valve provided between the discharge port of the discharge unit and the airtight container, and intermittently generates the liquid containing bubbles from the discharge port by operating the on-off valve. To do.

  In a preferred embodiment, the bubble generating device further includes a pressure gauge that detects a pressure in the hermetic container, and a control unit that controls the operation of the gas introduction device based on a value detected by the pressure gauge. .

  The bubble generation method of the present invention includes a step of introducing a gas into an airtight container containing a liquid and pressurizing the liquid to dissolve the gas in the liquid; and the liquid is provided in the airtight container. A step of discharging from the discharge port to the outside; and an inner diameter larger than an opening diameter of the discharge port, and the liquid is retained in the conduit so that the liquid stays in the conduit connected to the discharge port for a predetermined time. Passing the liquid through.

  In a preferred embodiment, the step of passing the liquid through the conduit causes the liquid to stay in the conduit at a predetermined flow rate for 0.5 seconds or more.

  The bubble generation method of the present invention includes a step of introducing a gas into an airtight container containing a liquid and pressurizing the liquid to dissolve the gas in the liquid; and the liquid is provided in the airtight container. And a step of separating the bubbles contained in the liquid and having a diameter larger than a predetermined value from the liquid discharged from the discharge port.

  In a preferred embodiment, the step of separating the bubbles allows the liquid to pass through a mesh having a predetermined opening.

  According to the bubble generating device of the present invention, pressure is applied to the liquid to dissolve the gas, and bubbles are generated in the liquid by reducing the pressure of the liquid in which the gas is dissolved. For this reason, fine bubbles can be generated with a simple structure. Further, a small amount of liquid containing fine bubbles can be easily manufactured without requiring a large-scale apparatus.

  In addition, it has at least one of a conduit for promoting the generation of bubbles and generating a large number of fine bubbles, and a bubble separator for removing large-diameter bubbles from the generated bubbles. Can be generated automatically.

  First, with reference to FIG. 1, the structure of the bubble generator by this invention is demonstrated roughly. The bubble generating device 100 of the present invention includes an airtight container 1, a gas introduction device 2, and a discharge unit 6. The airtight container 1 is airtight and stores the liquid 4. The gas introduction device 2 is a device that can introduce gas at a high pressure, such as a compressor. The gas introducing device 2 is connected to the airtight container 1 by a pipe 5 and introduces the gas 3 into the airtight container 1 at a pressure equal to or higher than atmospheric pressure. The pipe 5 is preferably connected to the airtight container 1 so that the gas 3 is bubbled into the liquid 4. The pipe 5 is provided with an on-off valve 5a.

  The discharge unit 6 has a discharge port 7 and is provided in the airtight container 1. The discharge unit 6 discharges the liquid 4 in the airtight container 1 from the discharge port 7 to the outside. The discharge unit 6 is provided with an on-off valve 6a.

  When the gas 3 is introduced into the airtight container 1 at a pressure equal to or higher than the atmospheric pressure by operating the on-off valve 5 a of the pipe 5, a part of the gas 3 is dissolved in the liquid 4. However, most of the air fills the space 1a that is not filled with the liquid 4 in the airtight container 1, and increases the pressure in the airtight container 1. For this reason, the pressure of the liquid 4 is also increased. According to Henry's law, the mass of the gas dissolved in the liquid 4 is proportional to the pressure in the hermetic container 1. For example, consider a case where water is used as the liquid 4 and oxygen gas at 5 atm is introduced into the gastight container 1 as a gas. Since oxygen has a solubility of 31 ml / L with respect to water at room temperature and normal pressure, about 5 times as much oxygen is dissolved in the liquid 4 in the airtight container 1 at 5 atmospheres.

  Next, when the on-off valve 5a is closed and the on-off valve 6a is opened, the liquid 4 in the airtight container 1 is discharged from the discharge port 7 of the discharge unit 6 to the outside. For example, the liquid 4 is discharged into the container 51 holding the water 52 under atmospheric pressure. When the pressure of the liquid 52 around the discharge port 7 is lower than the pressure in the airtight container 1, the pressure of the discharged liquid 4 rapidly decreases, and the amount of oxygen that can be dissolved in the liquid 4 as the pressure decreases. Also decreases. For this reason, oxygen that cannot be dissolved in the liquid 4 discharged from the discharge port 7 appears as fine bubbles. In this way, the bubble generating device of the present invention generates the fine bubbles 53 in the liquid 52.

  In order for the generated fine bubbles 53 to sufficiently exhibit the above-described effects such as improvement in dispersibility, the fine bubbles 53 need to be dispersed in the liquid 4 for a long time. It is known that the time until the bubbles in the liquid rise and disappear is closely related to the size of the bubbles, and larger bubbles rise and disappear earlier. In addition, if the bubbles are large, the bubbles are likely to aggregate to easily generate larger bubbles, which causes the bubbles to disappear earlier.

  The inventor of the present application examined in detail the relationship between the size of bubbles and the residence time of bubbles in the liquid, and found that bubbles with a diameter of approximately 100 μm or more floated and disappeared in the liquid in a relatively short time. It was. That is, in order to generate bubbles having a long residence time, the diameter of the generated bubbles is preferably smaller than 100 μm. The diameter of the bubbles is more preferably 60 μm or less.

  As will be described in detail in the following embodiments, the bubble generating device of the present invention further includes a mechanism in which generated bubbles become fine bubbles having a small diameter. Specifically, in addition to the above-described configuration, the bubble generating device of the present invention promotes the generation of bubbles at the discharge port 7 of the discharge unit 6 and the conduit 60 for generating many fine bubbles, or the generated bubbles. A bubble separator 70 for removing bubbles having a large diameter is provided. The conduit 60 maintains a liquid discharged from the discharge port 7 of the discharge unit 6 in a laminar flow state for a predetermined time, thereby generating a large number of nuclei for generating bubbles, and the generated bubbles are condensed and large bubbles are generated. Is suppressed. The bubble separator 70 separates and removes bubbles having a large diameter so that bubbles generated from the bubble generating device of the present invention include only bubbles having a small diameter.

  FIG. 2 shows an example of the time lapse of the particle size distribution of bubbles generated by the bubble generator of the present invention described below. As shown in FIG. 2, the diameter of the bubbles generated by the bubble generating apparatus of the present invention is approximately in the range of submicron to several tens of microns. As shown in FIG. 2, the bubbles having a large diameter decrease as time passes after the bubbles are generated, but the bubbles having a diameter of approximately 20 μm or less remain in the liquid with almost no disappearance. In the example shown in FIG. 2, even after 3 hours from the generation of bubbles, bubbles of approximately 20 μm or less are dispersed in the liquid with almost no disappearance.

  The bubbles generated by the bubble generator of the present invention are approximately in the range of submicron to several tens of microns, and the size of the bubbles is at or below the identification limit by the naked eye. For this reason, it is difficult to visually confirm the bubbles generated by the bubble generator of the present invention, and the bubbles do not appear to be clouded in the liquid. For example, water containing bubbles generated by the bubble generator of the present invention is colorless and transparent.

  On the other hand, bubbles in a jet bath used in a bathtub or the like are of a size that can be sufficiently confirmed with the naked eye. In a liquid containing bubbles of several hundred microns to several millimeters, the bubbles appear cloudy. For this reason, a liquid containing bubbles having a size of several hundred microns or more and a liquid containing bubbles generated by the bubble generating apparatus of the present invention can be easily distinguished.

  Since microbubbles of such a size are difficult to float in the liquid, (1) the function of improving the dispersibility of suspended matters in water, (2) the function of improving the gas absorption efficiency of the liquid, and (3) the fineness The oxidative degradation action of the liquid containing bubbles and (4) the inactivation action of the virus of the liquid containing fine bubbles can be further enhanced.

  Moreover, according to the bubble generating apparatus of the present invention, pressure is applied to the liquid to dissolve the gas, and bubbles are generated in the liquid by reducing the pressure of the dissolved liquid. For this reason, it is possible to generate fine bubbles with a simple configuration in which an airtight container and a gas introducer that introduces gas into the airtight container at a high pressure are main components. In addition, since a small amount of liquid containing fine bubbles can be easily produced without requiring a large-scale device, the bubble generating device of the present invention can be suitably used for household equipment or medical welfare equipment. Hereinafter, embodiments of the bubble generating apparatus of the present invention will be described in more detail.

(First embodiment)
FIG. 3 is a schematic diagram showing a first embodiment of a bubble generating device according to the present invention. The bubble generating device 101 includes an airtight container 1, a gas introducing device 2, a discharge unit 6, and a conduit 60. The airtight container 1 is airtight and stores the liquid 4. The airtight container 1 has an appropriate internal volume according to the use of the bubble generating device 101 and the required generation capacity. The internal volume of the airtight container 1 is not particularly limited due to the structure of the bubble generating device 101, and may be about several tens of ml or about several tens of liters. However, the present invention can be suitably used particularly for household appliances. When the present invention is applied to household appliances, the inner volume of the airtight container 1 is about 50 ml to 10,000 ml. Is preferred. In this embodiment, the internal volume of the airtight container 1 is 150 ml.

  The airtight container 1 has a pressure resistance of about 10 atmospheres. Although not shown in FIG. 3, the airtight container 1 includes an opening / closing port for introducing the liquid 4 into the airtight container 1. Instead of the opening / closing port, a pipe for introducing the liquid 4 and an opening / closing valve provided in the pipe may be provided in the airtight container 1.

  The liquid 4 for generating bubbles is preferably water, a hydrophilic solvent, or a mixture thereof. Examples of hydrophilic solvents that can be used include esters such as ethanol, polyhydric alcohols, acetone, and ethyl acetate. In this embodiment, 100 ml of pure water was introduced into the airtight container 1 as the liquid 4.

  The gas introducer 2 introduces gas into the airtight container 1 at a pressure equal to or higher than atmospheric pressure. For example, compressors, pumps, cylinders, and the like having various mechanisms can be used for the gas introduction device 2. Further, the gas introducing device 2 may be a gas cylinder that stores a compressed or liquefied gas. The pressure at which the gas introducing device 2 pressurizes the gas 3 is equal to or lower than the pressure resistance of the airtight container 1 and is preferably in the range of 2 to 30 atmospheres. When a high-pressure gas cylinder is used as the gas introducing device 2, it is preferable to provide an appropriate pressure reducing device such as a regulator as necessary.

  The gas introducing device 2 is connected to the airtight container 1 by a pipe 5 and introduces the gas 3 into the airtight container 1 at a pressure equal to or higher than atmospheric pressure. It is preferable to introduce the gas 3 from the bottom of the airtight container 1 to the inside of the airtight container 1 so that the gas 3 is bubbled into the liquid 4 and the introduced gas 3 is in sufficient contact with the liquid 4. The pipe 5 is provided with an on-off valve 5a.

  As described above, by bubbling the gas 3 from the gas introducer 2 into the liquid 4 at a predetermined pressure, a part of the introduced gas 3 is dissolved in the liquid 4 and the rest is the liquid in the airtight container 1. 4 fills the unfilled space 1 a and increases the pressure in the airtight container 1. Thereby, the pressure of the gas 3 and the liquid 4 also increases.

  As the gas 3, oxygen gas, ozone gas, nitrogen gas, carbon gas, hydrogen gas, air containing negative ions, and gas containing at least one of group 18 element gas can be used. The mixed gas can be selected according to the application. Air mainly containing nitrogen gas and oxygen gas is one of the gases that can be easily used in the gas generator 101. Table 1 shows the solubility of these gases in water at 1 atm and 20 ° C.

When a mixed gas is used as the gas 3, the Henry constant K _i is used between the molar fraction x _{i of} each gas in the liquid 4 and the partial pressure p _{i of the} gas, so that K _i = p _i / x _i A relationship is established. That is, the solubility of each gas is proportional to the partial pressure. In this embodiment, an oxygen cylinder was used as the gas introducing device 2, and oxygen was introduced into the airtight container 1 by a regulator at 5 atm for about 20 minutes.

  The discharge unit 6 has a pipe 8 and a discharge port 7 and is provided in the airtight container 1. Specifically, one end of the pipe 8 is connected to the airtight container 1 and the discharge port 7 is provided at the other end. The discharge port 7 is, for example, an orifice. The discharge unit 6 discharges the liquid 4 in the airtight container 1 from the discharge port 7 to the outside. The discharge unit 6 is provided with an on-off valve 6a. The pipe 8 may have a linear shape as long as it is not deformed by the pressurized liquid 4, or may be a flexible tube that can be bent with a gentle curvature. The opening diameter (diameter) of the discharge port 7 depends on the required bubble generation capability and the capacity of the airtight container 1. When the present invention is applied to household equipment, the opening diameter r1 of the discharge port 7 is preferably in the range of 0.1 mm to 5 mm. In the present embodiment, an orifice having an opening diameter r1 of 0.5 mm and a depth (length) of 2 mm is used as the discharge unit 6.

  By operating the on-off valve 6a, the liquid 4 discharged from the discharge port 7 is released to an external pressure. At this time, the pressure of the liquid 4 is reduced, and the dissolved gas 3 becomes bubbles and gasifies. As described above, at this time, the conduit 60 is connected to the discharge port 7 of the discharge unit 6 in order to promote the generation of bubbles and generate many fine bubbles. The conduit 60 has an inner diameter larger than the opening diameter of the discharge port 7 and is connected to the discharge port 7. The other end of the conduit 60 is connected to a container 51 filled with water 52.

  The conduit 60 maintains the liquid 4 released to external pressure in a regular flow for a certain period of time. Thereby, the production | generation of the nucleus for a bubble to generate | occur | produce can be promoted, and more fine bubbles can be generated. For this purpose, as shown in FIG. 4, the liquid 4 flowing through the conduit 60 is preferably laminar. When the liquid 4 has a laminar flow with a velocity distribution such that the liquid 4 decreases from the center of the conduit 60 toward the wall surface of the conduit 60 as indicated by an arrow 4a, stress is generated between adjacent velocity layers. , Nuclei for generating bubbles are generated. For this reason, more fine bubbles are generated in the liquid 4 by keeping the laminar flow long. The conduit 60 may also have a linear shape with the pipe 8 or may be a flexible tube that can be bent with a gentle curvature. Thereby, the liquid 4 containing a lot of fine bubbles is introduced into the water 52 held in the container 51, and the fine bubbles 53 are dispersed in the water 52.

  FIG. 5 is a graph showing the particle size distribution of bubbles generated by the bubble generator 101. The horizontal axis indicates the bubble particle size, and the vertical axis indicates the frequency. For the measurement, a particle size distribution meter manufactured by MICROTEC was used, and the measurement was performed on the liquid 4 after 5 minutes passed from the conduit 60 so that the measurement was stabilized. As shown by a curve 42 in FIG. 5, the particle diameters of the bubbles generated by the bubble generator 101 are distributed within the range of about 0.5 μm to about 60 μm, and almost all the bubbles having a particle diameter larger than 60 μm are generated. Not.

  For comparison, the conduit 60 was removed from the bubble generating device 101, and the particle size distribution when bubbles were generated and the particle size distribution of pure water used for generating bubbles were examined. As shown by the curve 41, when bubbles are generated without using the conduit 60, the generated bubbles have a particle size of 10 μm or more, and many bubbles having a particle size of about 200 μm are generated. Further, as shown by the curve 44, it is understood that the pure water introduced into the bubble generating device 101 does not contain bubbles of about 500 μm or less.

  As is clear from FIG. 5, fine bubbles having a particle size of 60 μm or less can be generated by the bubble generator 101 provided with the conduit 60. Moreover, it not only contains fine bubbles, but bubbles having a particle size of 60 μm or more are hardly generated. Because it does not contain bubbles that have a large particle size and immediately float in the liquid, fine bubbles having a particle size of 60 μm or less are dispersed in the liquid for a long time without floating along with the floating bubbles. Alternatively, it can stay.

  Next, the optimum shape of the conduit 60 will be described. As described above, the conduit 60 has a function of generating many nuclei for generating bubbles. For this reason, it is preferable that the liquid 4 opened to atmospheric pressure maintains a flow in which the liquid 4 is arranged for a certain period of time. FIG. 6 is a graph showing the relationship between the time spent in the conduit 60 and the average particle size of the generated bubbles. As is apparent from FIG. 6, when the residence time in the conduit 60 is shorter than 0.5 seconds, the average particle diameter of the generated bubbles is remarkably increased. On the other hand, when the residence time is 0.5 seconds or more, the average particle size of the bubbles is about 10 μm or less, and the average particle size becomes smaller as the residence time becomes longer. From this, it can be seen that the liquid 4 discharged from the discharge port 7 preferably stays in the conduit 60 for 0.5 seconds or more.

  The residence time of the conduit 60 depends on the discharge speed, which is the flow rate of the liquid 4. It also depends on the inner diameter of the conduit 60 and the discharge port 7. As a result of the detailed experiment, as shown in FIG. 3, if the opening diameter r1 of the discharge port 7 is in the range of 0.1 mm to 5 mm, the inner diameter of the conduit 60 is in the range of 0.5 mm to 10 mm, The length l is preferably 50 mm or more.

  Moreover, it is preferable that the conduit | pipe 60 is a parallel pipe | tube without an internal diameter change, and forms the parallel flow path so that the liquid 4 which flows through the conduit | pipe 60 may maintain a laminar flow state easily. It is not preferable to use a Venturi tube whose channel is enlarged. Further, when the venturi tube is used as the conduit 60, the pressure of the liquid 4 rapidly decreases and becomes a negative pressure as the flow path is enlarged. There is also a problem that the gas dissolved in the liquid 4 is suddenly boiled due to a rapid pressure drop and large bubbles are generated.

  As described above, according to the present embodiment, by introducing the gas into the airtight container containing the liquid while being pressurized, the gas is dissolved in the liquid in a pressurized state, and the pressure of the pressurized liquid is reduced. The dissolved gas is generated as bubbles. For this reason, an airtight container and a gas introducing device capable of pressurizing and introducing a gas into the airtight container need only be provided as main components, and a bubble generating device that has a simple structure and does not require a large structure is realized. be able to. In addition, when discharging pressurized liquid from the discharge port, it passes through the conduit for a predetermined time while adjusting the flow of the liquid, thereby promoting nucleation for generating bubbles and generating many minute bubbles. be able to. For this reason, it is possible to suppress the growth of bubbles having a large particle size having buoyancy and to generate many fine bubbles.

(Second Embodiment)
FIG. 7 is a schematic diagram showing a second embodiment of the bubble generating device according to the present invention. A bubble generating device 102 shown in FIG. 7 includes an airtight container 1, a gas introducing device 2, a discharge unit 6, a conduit 60, and a bubble separator 70. The bubble generation device 102 is different from the bubble generation device 101 of the first embodiment in that it further includes a bubble separator 70. The airtight container 1, the gas introduction device 2, the discharge unit 6 and the conduit 60 of the bubble generating device 102 function as described in the first embodiment, and a liquid containing fine bubbles is discharged from the conduit 60.

  The bubble separator 70 is connected to the conduit 60, and separates bubbles contained in the liquid and having a diameter larger than a predetermined value from the liquid containing fine bubbles discharged from the conduit 60. For this purpose, the bubble separator 70 includes a sieve 62 having a pair of main surfaces and a plurality of through-openings of a predetermined size provided on the main surfaces. Specifically, the sieve 62 is a net having a predetermined mesh, a separation membrane provided with a plurality of through holes of a predetermined size, or a ceramic plate. The through opening is not limited to a circle or a rectangle, and may be a slit, for example.

  By disposing the sieve 62 so as to block the flow path of the liquid 4 discharged from the conduit 60, the bubbles contained in the liquid 4 and having a diameter larger than the through opening are blocked by the sieve 62, and the liquid 4 and the through opening. Only bubbles having a smaller diameter pass through the sieve 62. In this way, large bubbles of the fine bubbles in the liquid 4 can be separated.

  In order to efficiently separate bubbles having a diameter larger than a predetermined value, it is preferable to use a sieve 62 having a large aperture ratio, and it is more preferable to use a mesh as the sieve 62. Further, it is preferable that the bubble separator 70 is configured so that bubbles having a large diameter separated by the sieve 62 do not come into contact with the liquid 4 that has passed through the sieve 62. For this purpose, the bubble separator 70 has an introduction port 61a for introducing the liquid 4, a discharge port 61b for discharging the liquid from which large bubbles are separated, and a bubble discharge port 63c for discharging large bubbles. A conduit 61 is included. The sieve 62 is disposed between the inlet 61a and the outlet 61b so as to block the flow path of the liquid 4 defined by the pipe 61. In addition, the bubble discharge port 63c is provided at a position where the bubble blocked from passing through the sieve 62 in the pipeline 61 rises. More preferably, from the 1 degree with respect to the direction in which the flow path of the liquid 4 extends, the main surface of the sieve 62 on the side of the inlet 61a faces the bubble outlet 61c so that the bubbles blocked by the sieve 62 are likely to rise. It is installed so that there is no path other than a sieve for the entire flow with an angle θ of 90 degrees. Further, since the sieve 62 is disposed so as to block the flow path of the liquid 4, the sieve 62 becomes resistant to the flow of the liquid 4, and the liquid 4 overflows toward the bubble discharge port 61c. It is preferable that the bubble outlet 61c has a height 12 from the flow path of the liquid 4 so that the liquid 4 does not overflow from the bubble outlet 61c. The height l2 is preferably 2 cm or more.

  As described above, the generated fine bubbles preferably include those having a diameter of 60 μm or less. For this purpose, it has been found that a sieve 62 having an opening diameter of about twice the diameter, that is, a through opening of about 120 μm may be used. This is because even if the through-opening is larger than 60 μm in diameter, it cannot pass through the sieve 62 due to contact with the periphery of the through-opening. For example, when a linear 0.1 mm net is used, a 100-mesh opening has a through opening of approximately this size.

  A curve 43 in FIG. 4 shows the particle size distribution of the bubbles generated by the bubble generator 102. As is apparent from FIG. 4, bubbles having a diameter larger than 40 μm are hardly included. Further, as is clear from the comparison between the curve 43 and the curve 42, the provision of the bubble separator 70 not only removes bubbles having a predetermined particle diameter but also increases bubbles having a diameter of about several μm. You can see that

  According to the present embodiment, bubbles having a large particle size can be separated by the bubble separator 70, so that only fine bubbles can be obtained. For this reason, it is possible to obtain bubbles that stay in the liquid for a long time, and it is possible to further enhance the various effects described above due to the fine bubbles.

  In the present embodiment, the bubble separator 70 is connected to the conduit 60, but the conduit 60 may be omitted and the bubble separator 70 may be directly connected to the discharge port 7 of the discharge unit 6. By not using the conduit 60, the generation efficiency of fine bubbles is somewhat lowered, but the bubble separator 70 can reliably remove bubbles having a large particle size. For this reason, although the production efficiency is somewhat reduced, only fine bubbles having a diameter of 60 μm or less can be produced, and the above-described effects can be obtained.

(Third embodiment)
FIG. 8 is a schematic view showing a third embodiment of the bubble generating device according to the present invention. The bubble generation device 103 includes a structure for automatic control in addition to the structure of the bubble generation device 101 of the first embodiment, and can automatically generate bubbles. As shown in FIG. 8, the bubble generating device 103 includes an airtight container 1, a gas introducing device 2, a discharge unit 6, a conduit 60, a pressure gauge 71, a liquid level gauge 72, a pressure relief valve 73, and a control. The apparatus 74 and the on-off valves 5a, 6a, and 9a are provided.

  A pipe 9 for introducing the liquid 4 into the airtight container 1 is connected to the airtight container 1, and an opening / closing valve 9 a for controlling the flow rate of the liquid 4 flowing through the pipe 9 is provided in the pipe 9. The gas introducing device 2 and the airtight container 1 are connected by a pipe 5, and the pipe 5 is provided with an on-off valve 5 a. The piping 8 of the discharge unit 6 is provided with an on-off valve 6a.

  The hermetic container 1 is further provided with a liquid level gauge 72 for detecting the height of the liquid 4 and a pressure gauge 71 for detecting the pressure in the hermetic container 1. The pressure gauge 71 is provided with a pressure relief valve 73.

  The control device 74 controls the on-off valves 5a, 6a, and 9a based on the values detected by the liquid level gauge 72 and the pressure gauge 71, introduces the gas 3 and the liquid 4 into the airtight container 1, and the discharge unit 6 The liquid 4 containing bubbles is discharged from the discharge port 7. More specifically, the control device 74 controls the on-off valve 9a based on the detection result by the liquid level gauge 72 so that the amount of the liquid 4 in the hermetic container 1 is within a predetermined range. Moreover, based on the detection result by the pressure gauge 71, it controls so that the pressure in the airtight container 1 may become in a predetermined range. When the pressure increases beyond a predetermined range for some reason, the pressure relief valve 73 is opened to lower the pressure.

  Since the gas 3 introduced into the hermetic container 1 is dissolved in the liquid 4 and takes a predetermined time to reach an equilibrium state, for example, when the pressure detected by the pressure gauge 71 is maintained for a predetermined time, the gas 3 Is sufficiently dissolved in the liquid 4, and the on-off valve 6a is controlled to discharge the liquid 4 containing bubbles from the discharge port 7. With such a configuration, the bubble generating device 103 can be automatically controlled.

  In addition, by preparing two bubble generation devices 103 having this structure, in one bubble generation device 103, the gas 3 or the liquid 4 is introduced into the airtight container 1, and the gas 3 is dissolved in the liquid 4. While there is, the liquid 4 containing bubbles can be discharged from the other bubble generation device 103. Thereby, it becomes possible to generate bubbles continuously.

  In this embodiment, the bubble generating device 101 of the first embodiment is provided with a structure for performing automatic control. However, the bubble generating device 102 of the second embodiment has a structure for performing automatic control. It may be provided.

  As described above, the bubble generating apparatus of the present invention has a simple structure, and can freely adjust the capacity of the airtight container and the performance of the gas introducing device according to the required bubble generation capability. For this reason, in particular, it is possible to generate a small amount of liquid containing fine bubbles, which has been difficult with conventional bubble generating devices, and the bubble generating device of the present invention can be suitably used for household devices and medical welfare devices. it can. However, it is possible to apply the bubble generating device of the present invention to industrial equipment by increasing the capacity of the airtight container and using a gas introducing device capable of compressing a large amount of gas at a high pressure. Specifically, the present invention can be suitably used in the fishery field such as fish farms, the agricultural field, and the water purification field.

  The bubble generating device of the present invention is a device that uses a small amount of liquid containing fine bubbles, such as consumer household equipment and medical welfare equipment, a fishery field that uses a large amount of liquid containing fine bubbles, an agricultural field, and a water purification field. It can use suitably for industrial equipment, such as.

It is a figure which shows generally the structure of the bubble generator of this invention. It is a graph which shows an example of the time passage of the particle size distribution of the bubble produced | generated by the bubble generator of this invention. It is a figure which shows the structure of 1st Embodiment of the bubble generator by this invention. It is a figure explaining the state of the liquid which flows through the conduit | pipe of the bubble generator shown in FIG. It is a graph which shows the particle size distribution of the bubble produced | generated by the bubble generator of 1st Embodiment and 2nd Embodiment. In the bubble generator shown in FIG. 3, the residence time of the liquid in the conduit It is a figure which shows the structure of 2nd Embodiment of the bubble generator by this invention. It is a figure which shows the structure of 3rd Embodiment of the bubble generator by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Airtight container 2 Gas introducing device 3 Gas 4, 52 Liquid 5, 8, 9 Pipe 6 Discharge part 7 Discharge port 51 Container 53 Fine bubble 60 Conduit 61 Pipe line 62 Sieve 70 Bubble separator 100, 101, 102, 103 Bubble Generator

Claims (21)

An airtight container for storing liquid;
A gas introducer that introduces gas into the hermetic container and pressurizes the liquid to dissolve the gas in the liquid;
A discharge part provided in the airtight container, and having a discharge port for discharging the liquid from the airtight container to the outside;
A conduit having an inner diameter that is larger than the opening diameter of the outlet, and connected to the outlet;
A bubble generating device comprising:   The bubble generating device according to claim 1, wherein the conduit has a length in which the liquid discharged from the discharge port stays in the conduit at a predetermined flow rate for 0.5 seconds or more.   The bubble generating apparatus according to claim 2, wherein a length of the conduit is 50 mm or more.   The bubble generating device according to claim 1, wherein an opening diameter of the discharge port is 0.1 mm or more and 5 mm or less, and an inner diameter of the conduit is 0.5 mm or more and 10 mm or less. An airtight container for storing liquid;
A gas introducer that introduces gas into the hermetic container and pressurizes the liquid to dissolve the gas in the liquid;
A discharge part provided in the airtight container, and having a discharge port for discharging the liquid from the airtight container to the outside;
A bubble separator for separating bubbles contained in the liquid and having a diameter larger than a predetermined value from the liquid discharged from the discharge port;
A bubble generating device comprising:   The bubble separator includes a mesh having a predetermined opening, and the liquid having a diameter larger than the predetermined value is removed by passing the liquid discharged from the discharge port through the mesh. The bubble generating apparatus as described.   The bubble generating apparatus according to claim 6, wherein the net has an opening having a fineness of 100 mesh or more.   The bubble separator includes a conduit having an introduction port, a discharge port, and a bubble discharge port, and the mesh is provided to block the liquid flow path between the introduction port and the discharge port of the pipeline. The bubble generating device according to claim 7, wherein the bubble discharge port is provided in the pipe line so that the bubbles separated by the net rise and reach the bubble discharge port.   9. The apparatus according to claim 5, further comprising a conduit having an inner diameter larger than an inner diameter of the discharge port between the discharge port of the discharge unit and the introduction port of the bubble separator, and connected to the discharge port. The bubble generator described in 1.   The bubble generating device according to claim 9, wherein the conduit has a length in which the liquid discharged from the discharge port stays in the conduit at a predetermined flow rate for 0.5 seconds or more.   The bubble generating apparatus according to claim 10, wherein a length of the conduit is 50 mm or more.   The bubble generating apparatus according to claim 11, wherein an inner diameter of the discharge port is 0.1 mm or more and 5 mm or less, and an inner diameter of the conduit is 0.5 mm or more and 10 mm or less.   The bubble generating device according to claim 1, wherein the liquid is water or a hydrophilic solvent.   The bubble generating apparatus according to any one of claims 1 to 12, wherein the gas includes at least one of oxygen gas, ozone gas, nitrogen gas, carbon gas, hydrogen gas, air containing negative ions, and group 18 element gas.   The bubble generating apparatus according to claim 1, wherein the conduit has flexibility.   An on-off valve provided between the discharge port of the discharge unit and the airtight container is further provided, and the liquid containing bubbles is intermittently generated from the discharge port by operation of the on-off valve. The bubble generating device according to any one of the above. A pressure gauge for detecting the pressure in the airtight container;
Based on the value detected by the pressure gauge, a control unit for controlling the operation of the gas introducer;
The bubble generating device according to any one of claims 1 to 12, further comprising: Introducing a gas into an airtight container containing a liquid and dissolving the gas in the liquid by pressurizing the liquid; and
Discharging the liquid from an outlet provided in the airtight container to the outside;
Passing the liquid through the conduit so that the liquid stays in the conduit connected to the discharge port for a predetermined period of time, having an inner diameter larger than the opening diameter of the discharge port;
A method for generating bubbles.   The bubble generating device according to claim 18, wherein in the step of passing the liquid through the conduit, the liquid is retained in the conduit at a predetermined flow rate for 0.5 second or more. Introducing a gas into an airtight container containing a liquid and dissolving the gas in the liquid by pressurizing the liquid; and
Discharging the liquid from an outlet provided in the airtight container to the outside;
Separating air bubbles contained in the liquid and having a diameter larger than a predetermined value from the liquid discharged from the discharge port;
A method for generating bubbles. 21. The bubble generation method according to claim 20, wherein in the step of separating the bubbles, the liquid is passed through a mesh having a predetermined opening.

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