JP6605229B2 - Gas refinement device - Google Patents

Description

  The present invention relates to a gas refining apparatus that generates a fine bubble in a liquid by refining the gas.

  Microbubbles are expected to be used in many fields such as production of useful substances by culturing microorganisms, cultivation of high-quality larvae, and wastewater treatment.

A configuration is proposed in which a porous nozzle is provided in a pressure tank communicating with the side of the liquid tank, and a vibration source is brought into close contact with the porous nozzle, thereby vibrating the porous nozzle and generating fine bubbles in the liquid tank through the porous nozzle. (See Patent Document 1).

JP 2009-78223 A (FIG. 2)

  However, in the configuration of Patent Document 1, the porous nozzle is directly attached to the liquid tank, and the sealing performance against the liquid is not taken into consideration when the porous nozzle is vibrating.

  In order to solve the above-described problems, the present invention provides a gas micronization device that can generate bubbles in a liquid and ensure sealing performance against the liquid.

The gas refining apparatus of the present invention is a gas refining apparatus that generates a fine bubble by refining a gas.
A piezoelectric element having an opening in the central portion and a perforated diaphragm having a through hole in a portion corresponding to the opening of the piezoelectric element and arranged so as to overlap with the piezoelectric element and vibrate with the vibration of the piezoelectric element.
Moreover, it has the accommodating part provided with the supply part for providing the space which accommodates a piezoelectric element and a porous diaphragm, and supplying the gas used as a raw material to a porous diaphragm.
In addition, a sealing material that seals at least the liquid side of the piezoelectric element and / or the porous diaphragm is provided, and this sealing material is located at the end of the opening side of the piezoelectric element.
Further, in the piezoelectric element, the portion outside the contact portion between the piezoelectric element and / or the porous diaphragm and the sealing material is a free end that is not fixed.

  Further, in the gas miniaturization apparatus of the present invention described above, it is also possible to adopt a configuration in which the porous diaphragm is arranged so as to overlap the liquid side of the piezoelectric element.

  According to the above-mentioned present invention, the sealing element for sealing the liquid side of the piezoelectric element and / or the porous diaphragm is provided. Thereby, sufficient sealing is obtained with the sealing material, and the sealing performance against the liquid can be ensured.

1 is a schematic cross-sectional view of an embodiment of a miniaturization apparatus of the present invention. FIG. 2 is a plan view of a piezoelectric element and a porous diaphragm of the miniaturization apparatus of FIG. 1. It is a figure which shows an example of the use condition of the miniaturization apparatus of FIG. It is a figure which shows the various forms of A and B sealing materials. It is a figure which shows the various forms of a sealing material. It is a figure which shows the various forms of a sealing material. It is a schematic sectional drawing of other embodiment of the refinement | miniaturization apparatus of this invention. It is a schematic sectional drawing of other embodiment of the refinement | miniaturization apparatus of this invention.

  Hereinafter, modes for carrying out the invention (hereinafter referred to as “embodiments”) will be described.

FIG. 1 shows a schematic cross-sectional view of an embodiment of a gas refiner of the present invention (hereinafter abbreviated as “a refiner”).
A miniaturization apparatus 10 shown in FIG. 1 includes a piezoelectric element 11 and a porous diaphragm 12 disposed on the upper side of the piezoelectric element 11.
A wiring cable 14 for applying a voltage to the piezoelectric element 11 is connected to the piezoelectric element 11 at the right end in the figure.
A large number of fine through holes 13 are formed in the porous diaphragm 12.

As the piezoelectric element 11, a piezoelectric element having a conventionally known configuration, for example, a ceramic piezoelectric element can be used.
As the material of the porous diaphragm 12, a metal material can be used. Examples of the metal material used for the porous diaphragm 12 include stainless steel, nickel, platinum group metal (such as palladium) or an alloy thereof (for example, an alloy of palladium and nickel), gold or an alloy thereof, and the like.
The porous diaphragm 12 is fixed to the piezoelectric element 11 by adhesion or soldering.

Further, the main body of the miniaturization apparatus 10 is constituted by a base material 15.
In the central portion of the base material 15, a space that is long in the vertical direction from the bottom of the base material 15 and has an opening at the upper end is formed. A wide space is formed in the upper part of the base material 15, and the piezoelectric element 11 and the porous diaphragm 12 are disposed in this space, and the base material 15 accommodates the piezoelectric element 11 and the porous diaphragm 12. It is an accommodating part.
A supply unit 16 that supplies gas to the bottom of the porous diaphragm 12 is provided on the right side of the substrate 15 in the drawing. The supply unit 16 includes a passage from an outer edge of the base material 15 to a space in the center of the base material 15, and a raw material supply pipe (in FIG. Connected to the raw material supply pipe 18).
As the material of the base material 15, a strong and chemically stable material, for example, a metal such as stainless steel, a resin such as an epoxy resin, or a resin such as silicone or rubber can be used.

A plan view of the piezoelectric element 11 and the porous diaphragm 12 of the miniaturization apparatus 10 of FIG. 1 is shown in FIG.
As shown in FIGS. 1 and 2, the piezoelectric element 11 is a donut-shaped disk having a circular opening 11A in the center.
The porous diaphragm 12 is a disk that partially overlaps the doughnut-shaped piezoelectric element 11. The through hole 13 of the porous diaphragm 12 is formed in a region near the center of the porous diaphragm 12, and is formed in a portion corresponding to the opening 11A of the piezoelectric element 11 away from the edge of the opening 11A.

Then, when using the micronization apparatus 10 of the present embodiment, a gas as a raw material is supplied from the supply unit 16 of the base material 15 under the porous diaphragm 12 and a voltage is applied to the piezoelectric element 11. The piezoelectric element 11 is vibrated.
As a result, the porous diaphragm 12 connected to the piezoelectric element 11 vibrates, and bubbles are supplied from the through holes 13 of the porous diaphragm 12 to the liquid on the porous diaphragm 12.

In the miniaturization apparatus 10 of the present embodiment, in particular, the gap between the piezoelectric element 11 and the porous diaphragm 12 and the base material 15 is sealed with a sealing material 21.
The sealing material 21 is formed in contact with the piezoelectric element 11 or the porous diaphragm 12 and filling the gaps between the piezoelectric element 11 and the porous diaphragm 12 and the base material 15.
The sealing material 21 is in contact with part of the lower surface of the piezoelectric element 11 and part of the upper surface of the porous diaphragm 12.
Each sealing material 21 is located at an end (inner peripheral end) on the opening 11 </ b> A side of the piezoelectric element 11.
Although not shown, the sealing material 21 is formed on the entire circumference along the circular opening 11 </ b> A of the piezoelectric element 11 in order to seal between the piezoelectric element 11 and the porous diaphragm 12 and the base material 15. ing.

  The liquid side of the porous diaphragm 12 is sealed by a sealing material 21 between the porous diaphragm 12 and the base material 15 thereabove. Further, the gas side of the piezoelectric element 11 is sealed by a sealing material 21 between the piezoelectric element 11 and the base material 15 below the piezoelectric element 11.

Of the piezoelectric element 11, the portion outside the contact portion with the sealing material 21 is exposed to the space up to the outer peripheral end of the piezoelectric element 11, and the outer peripheral end of the piezoelectric element 11 is a free end. . Thereby, the part outside the contact part with the sealing material 21 of the piezoelectric element 11 can be sufficiently vibrated.
On the other hand, since the contact portion of the piezoelectric element 11 with the sealing material 21 is a fixed end, it becomes a node when the piezoelectric element 11 vibrates.

As the material of the sealing material 21, various resins, silicone, rubber and the like can be used.
Furthermore, the sealing material 21 has elasticity to some extent so that the state of contact with the piezoelectric element 11 and the porous diaphragm 12 can be stably maintained even against strong vibration or impact. More preferred. As such a material having elasticity, an elastic resin such as silicone or rubber is suitable. If a resin such as silicone or rubber is used as the material of the base material 15 as described above, the sealing material 21 is used as the base material. 15 can be formed integrally.

Next, FIG. 3 shows an example of the usage state of the miniaturization apparatus 10 of the present embodiment.
As shown in FIG. 3, the miniaturization apparatus 10 of the present embodiment is submerged in the bottom of a water tank 100 in which a liquid 101 such as water is stored.
A raw material supply pipe 18 for supplying a gas as a raw material from the outside of the water tank 100 to the miniaturization apparatus 10 and a wiring cable 14 for applying a voltage to the piezoelectric element 11 are provided in the miniaturization apparatus 10 in the water tank 100. It is connected.
An oscillator 17 that oscillates an AC voltage applied to the piezoelectric element 11 is connected to the wiring cable 14.
A raw material container 20 is connected to the raw material supply pipe 18 via a pressure regulator 19 that adjusts the pressure. In the case where bubbles are produced by the micronizer 10 using gas as a raw material, a gas cylinder or the like can be used for the raw material container 20.

  In this state, the raw material gas is supplied from the raw material container 20 to the micronizer 10 through the pressure regulator 19 and the raw material supply pipe 18, and the alternating voltage oscillated by the oscillator 17 is supplied to the piezoelectric element via the wiring cable 14. 11 is applied. Thereby, bubbles can be generated from the through holes of the porous diaphragm 12 and supplied to the liquid 101 of the water tank 100.

By using the miniaturization device 10 in this way, it is possible to supply a sufficient amount of bubbles into the liquid 101 of the water tank 100 even if the miniaturization device 10 body is downsized.
Further, after use, the miniaturization apparatus 10 can be taken out of the water tank 100, and the miniaturization apparatus 10 can be submerged in another water tank for use.

  When supplying bubbles to the micronizer 10, oxygen, ozone, nitrogen, carbon dioxide or the like can be used as the raw material gas in addition to air.

According to the above-described miniaturization apparatus 10 of the present embodiment, the sealing material that contacts the piezoelectric element 11 and the porous diaphragm 12 and seals the liquid side and the gas side of the piezoelectric element 11 and the porous diaphragm 12 respectively. By providing 21, sufficient sealing against the liquid can be obtained.
In addition, since the sealing material 21 can prevent liquid from entering the connecting portion between the piezoelectric element 11 and the wiring cable or the like, insulation can also be realized.
Furthermore, since the sealing material 21 is located at the end (inner peripheral end) on the opening side of the piezoelectric element 11, the fine bubbles are generated without suppressing the vibration of the piezoelectric element 11 and the porous diaphragm 12. Can be generated in a sufficient amount.

An electrode (generally a thick film electrode formed by firing silver or a paste mainly composed of silver) is formed on the surface of the piezoelectric element 11 used in the gas miniaturization apparatus 10 of the present invention. This electrode is easily corroded in an electrolytic solution by applying an electric field for driving the piezoelectric element 11.
For this reason, in the miniaturization apparatus 10 of the present embodiment, the porous diaphragm 12 is placed on the upper side (liquid side) of the piezoelectric element 11 and the liquid side of the porous diaphragm 12 is sealed with the sealing material 21. As a result, the electrodes of the piezoelectric element 11 can be prevented from being directly exposed to the liquid, so that the corrosion reliability can be improved.
In applications such as purification of polluted water, fermentation, and the like, the effect of increasing the corrosion reliability is particularly exhibited because it is brought into contact with a liquid having high electrolysis.

  Further, since the micronization device 10 of the present embodiment uses the porous diaphragm 12, only the target bubbles can be miniaturized, and no load is applied to the supply destination liquid. Therefore, for example, it is possible to generate bubbles without adversely affecting microorganisms in the supply destination liquid.

In addition, the miniaturization apparatus 10 of the present embodiment can basically configure the miniaturization apparatus 10 with the base material 15, the piezoelectric element 11, the porous diaphragm 12, and the sealing material 21. And even if the piezoelectric element 11 and the porous diaphragm 12 are about 1 cm to several cm in diameter, they are sufficient for gas miniaturization, so the miniaturization apparatus 10 can be miniaturized.
Further, by arranging a large number of miniaturization devices 10, it is possible to scale up.

  In FIG. 1, the sealing material 21 is in contact with the lower surface of the piezoelectric element 11 and the upper surface of the porous diaphragm 12, but the target with which the sealing material 21 comes into contact is not limited to this combination. Any configuration may be used as long as the liquid side of the porous diaphragm 12 is sealed by the sealing material 21 and the sealing material 21 is located at the end of the piezoelectric element 11 on the opening 11A side. For example, the sealing material 21 provided on the upper side of the piezoelectric element 11 and the porous diaphragm 12 may be configured to contact from the upper surface of the porous diaphragm 12 to the upper surface of the piezoelectric element 11.

In addition, the piezoelectric element 11 and the porous diaphragm 12 can employ various configurations as long as the sealing material 21 can seal the substrate 15.
For example, the opening 11A of the piezoelectric element 11 is not limited to a circle, and may be other shapes such as a rectangle.
In FIG. 2, the through hole 13 of the porous diaphragm 12 is formed inwardly from the edge of the opening 11 </ b> A of the piezoelectric element 11. For example, the through hole 13 of the porous diaphragm 12 is formed at the opening of the piezoelectric element 11. You may form uniformly in 11A.

In FIG. 1, the sealing material 21 on the upper side (liquid side) of the porous diaphragm 12 and the sealing material 21 on the lower side (gas side) of the piezoelectric element 11 have the same configuration.
When water pressure is applied from above the vibration element including the piezoelectric element 11 and the porous diaphragm 12, the vibration element is displaced downward by the water pressure. For this reason, it is better that the upper and lower sealing materials 21 of the vibration element have different configurations corresponding to the displacement of the vibration element due to water pressure. For example, the sealing material 21 above the vibration element is longer than the sealing material 21 below the vibration element, or the sealing material 21 above the vibration element is lower than the sealing material 21 below the vibration element. A configuration with hardness is conceivable.

  In the miniaturization apparatus 10 of the embodiment shown in FIGS. 1 to 2, the sealing material 21 is in contact with the piezoelectric element 11 and the porous diaphragm 12. In the miniaturization apparatus of the present invention, the shape of the sealing material 21 and the contact state between the vibration element (piezoelectric element and porous diaphragm) and the sealing material are limited to the configuration of the embodiment shown in FIGS. Is not to be done.

  Next, various forms of the sealing material provided on the liquid side of the vibration element are shown in FIGS. 4A to 4B, 5, and 6. In these drawings, the same reference numerals as those in FIG. 1 are used for the bubbles 1, the base material 15, the piezoelectric element 11, and the porous diaphragm 12.

The form shown in FIG. 4A uses a sealing material 41 in which the contact portion with the vibration element is a thin double cylindrical surface.
In the form shown in FIG. 4B, the same sealing material 21 as in FIG. 1 is fixed to the porous diaphragm 12 of the vibration element with an adhesive 42 made of an elastic adhesive resin. As shown in FIG. 4B, if the contact portion of the sealing material 21 is fixed with the adhesive 42 made of an elastic adhesive resin, the contact width with respect to the vibration element is increased, the pressure resistance of the sealing is increased, Since the sealing performance can be improved, the sealing performance (waterproofness) can be maintained with high vibration efficiency.

In the form shown in FIG. 5, the upper side of the vibration element is the same sealing material 21 as that of FIG. It is a configuration. Since the upper side of the vibration element is on the liquid side, sealing is necessary. However, since the lower side of the vibration element is on the gas side, it may not be sealed. In FIG. 5, the piezoelectric element 11 of the vibration element is placed on the holding material 43.
In the base material 15, the upper base material 15 </ b> A and the lower base material 15 </ b> B are joined using bolts 50. Since the base material 15 has such a configuration, it is conceivable to use the holding material 43 so that the vibration elements do not shift when the upper and lower base materials 15A and 15B are assembled.

  In the form shown in FIG. 6, the sealing material 21 is fixed to the vibration element with the adhesive 42 on the upper side of the vibration element as in FIG. 4B, and the holding material 43 shown in FIG. 5 is not necessary. .

  In this embodiment, there is a gap between the vibration element and the base material 15, and the vibration element is not in contact with the base material 15. For this reason, the vibration element can be easily vibrated freely. In addition, the degree of design freedom is increased for the structure and assembly of the gas micronizer.

  Each of the forms shown in FIGS. 4A to 4B, 5, and 6 described above is provided at the end of the piezoelectric element 11 on the opening 11 </ b> A side, similarly to the miniaturization apparatus 10 shown in FIGS. 1 to 2. The sealing material 21 is located.

Next, FIG. 7 shows a schematic cross-sectional view of another embodiment of the miniaturization apparatus of the present invention.
7 uses the O-ring instead of the sealing material 21 of the microfabrication apparatus 10 of FIGS. 1-2, and has comprised the sealing material 45. In FIG.
The sealing material 45 is provided on the upper side (liquid side) of the porous diaphragm 12 and the lower side (gas side) of the piezoelectric element 11, and seals the liquid side of the porous diaphragm 12 and the gas side of the piezoelectric element 11. is doing. Each sealing material 45 is located at the end (inner peripheral end) on the opening 11 </ b> A side of the piezoelectric element 11.
The sealing material 45 made of an O-ring is formed on the entire circumference in a ring shape along the circular opening 11A of the piezoelectric element 11 (not shown).

In the miniaturization apparatus 30 shown in FIG. 7, an upper base material 48 is disposed on the base material 15 outside the piezoelectric element 11 via an O-ring 46 having a small diameter. Further, the wiring cable 14 is passed through a hole formed in the base material 15, and the hole is filled with a filler 47.
Other configurations are the same as those of the miniaturization apparatus 10 of the embodiment shown in FIGS.

According to the miniaturization apparatus 30 of the present embodiment, the sealing material 45 that contacts the piezoelectric element 11 and the porous diaphragm 12 and seals the liquid side and the gas side of the piezoelectric element 11 and the porous diaphragm 12 respectively. By providing, sufficient sealing with respect to the liquid can be obtained.
In addition, since the sealing material 45 can prevent liquid from entering the connecting portion between the piezoelectric element 11 and the wiring cable or the like, insulation can also be realized.
Further, since the sealing material 45 is located at the end (inner peripheral end) of the piezoelectric element 11 on the opening 11A side, the vibration of the piezoelectric element 11 and the porous diaphragm 12 is not suppressed, and the sealing material 45 is fine. A sufficient amount of bubbles can be generated.

FIG. 8 shows a schematic cross-sectional view of still another embodiment of the miniaturization apparatus of the present invention.
The micronization device 40 shown in FIG. 8 has the piezoelectric element 11 and the porous diaphragm 12 upside down with respect to the micronization apparatus 10 of FIGS. That is, they are arranged on the liquid side.

The sealing material 21 is in contact with part of the upper surface of the piezoelectric element 11 and part of the lower surface of the porous diaphragm 12.
The liquid side of the piezoelectric element 11 is sealed by a sealing material 21 between the piezoelectric element 11 and the base material 15 thereabove. In addition, the gas side of the porous diaphragm 12 is sealed by a sealing material 21 between the porous diaphragm 12 and the base material 15 below the porous diaphragm 12.

In the miniaturization apparatus 40 of the present embodiment, since the piezoelectric element 11 is arranged on the liquid side, the end of the piezoelectric element 11 on the opening side (in particular, the inner peripheral end of the upper surface of the piezoelectric element 11 and the side surface of the opening). ) Is exposed to liquid. Therefore, in the portion of the piezoelectric element 11 exposed to the liquid, in order to prevent corrosion of the electrode of the piezoelectric element, the electrode is not provided in the portion, or the portion is thickened so that the liquid does not directly touch the electrode. It is conceivable to provide an insulating overcoat with a thickness of several μm to several tens of μm. As the overcoat material, glass or water-resistant resin is used.
In addition, the rigidity of this overcoat becomes resistance to vibration, which can cause a decrease in vibration efficiency. Therefore, it is desirable not to provide an overcoat on the portion of the piezoelectric element 11 that is not exposed to the liquid.

  Other configurations are the same as those of the miniaturization apparatus 10 of the embodiment shown in FIGS.

According to the miniaturization apparatus 40 of the present embodiment, the sealing material 21 that contacts the piezoelectric element 11 and the porous diaphragm 12 and seals the liquid side and the gas side of the piezoelectric element 11 and the porous diaphragm 12 respectively. By providing, sufficient sealing with respect to the liquid can be obtained.
In addition, since the sealing material 21 can prevent liquid from entering the connecting portion between the piezoelectric element 11 and the wiring cable or the like, insulation can also be realized.
Furthermore, since the sealing material 21 is located at the end (inner peripheral end) of the piezoelectric element 11 on the opening 11A side, the vibration of the piezoelectric element 11 and the porous diaphragm 12 is not suppressed, and the sealing material 21 is fine. A sufficient amount of bubbles can be generated.

  As in the miniaturization apparatus 10 shown in FIG. 1, the porous diaphragm 12 is placed on the upper side (liquid side) of the piezoelectric element 11, and the liquid side of the porous diaphragm 12 is sealed with the sealing material 21. When stopped, it can be avoided that the electrode of the piezoelectric element 11 is directly exposed to the liquid. Therefore, when the porous diaphragm 12 is arranged on the liquid side as in the miniaturization apparatus 10 shown in FIG. 1, the piezoelectric element 11 has no overcoat, or the piezoelectric element 11 has a thin overcoat. Even if it is the structure currently formed, corrosion reliability can be improved.

  In the miniaturization apparatuses 10, 30, and 40 of the above-described embodiments, the wiring cable 14 is connected above and below the right end portion of the piezoelectric element 11, and the wiring cable 14 is passed through the base material 15 on the right side of the piezoelectric element 11. . In the miniaturization apparatus of the present invention, the connection position of the piezoelectric element and the wiring cable and the way of passing the wiring cable through the base material are not limited to the configurations of these embodiments.

The usage mode of the micronizing apparatus of the present invention is not limited to the mode of sinking in the bottom of a liquid tank such as the water tank 100 as shown in FIG.
For example, as in the configuration of Patent Document 1, the miniaturization apparatus of the present invention may be provided on the side surface of the liquid tank.
In this case, among the piezoelectric element and the porous diaphragm of the vibration element, the liquid side is disposed inside the liquid tank, and the gas side is disposed outside the liquid tank.
As a configuration in which the micronization device is provided on the side surface of the liquid tank, a configuration in which the base material is attached to the side surface of the liquid tank or a configuration in which the side surface of the liquid tank also serves as the base material can be considered. In any case, since the liquid side of the vibration element is sealed with the sealing material by providing the micronization device of the present invention on the side surface of the liquid tank, the porous diaphragm is directly connected to the side surface of the liquid tank. As compared with the configuration of Patent Document 1, the liquid-side sealing can be reliably performed.

  The present invention is not limited to the above-described embodiments, and various other configurations can be taken without departing from the gist of the present invention.

  The gas refinement apparatus of the present invention includes, for example, food (vinegar brewing, production of useful substances using microorganisms), aquaculture (especially improving the survival rate of high-grade fish larvae, improving the bactericidal effect of pathogenic bacteria), cooling water equipment (microorganisms) It is useful in various fields such as heat exchange efficiency improvement by control), drinking water (inhibition of clogging of water purification membrane, microbial control), and wastewater treatment (improvement of decomposition of microorganisms by air supply, improvement of decomposability by fine ozone).

10, 30, 40 Micronizer, 11 Piezoelectric element, 12 Porous diaphragm, 13 Through hole, 14 Wiring cable, 15 Substrate, 16 Supply unit, 17 Oscillator, 18 Raw material supply pipe, 19 Pressure regulator, 20 Raw material container 21, 41 Sealing material, 42 Adhesive material, 43 Holding material, 45 Sealing material (O-ring), 100 Water tank, 101 Liquid

Claims (2)

A gas refining device that generates a fine bubble in a liquid by refining a gas,
A piezoelectric element having an opening in the center;
A perforated diaphragm having a through hole in a portion corresponding to the opening of the piezoelectric element, and being arranged so as to overlap the piezoelectric element, and vibrates with vibration of the piezoelectric element;
A housing section comprising a space for housing the piezoelectric element and the porous diaphragm, and a supply section for supplying a gas as a raw material to the porous diaphragm;
A sealing material for sealing at least the liquid side of the piezoelectric element and / or the porous diaphragm;
The sealing material is located at an end of the piezoelectric element on the opening side ,
The piezoelectric element is a gas miniaturization apparatus in which a portion outside the contact portion between the piezoelectric element and / or the porous diaphragm and the sealing material is a free end that is not fixed .   The gas refining apparatus according to claim 1, wherein the porous diaphragm is disposed so as to overlap the liquid side of the piezoelectric element.

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