JP2011218308A - Gas-dissolved liquid generating apparatus and method for generation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas-dissolved liquid generating apparatus capable of applying generation of nanobubble water (high zeta potential water).SOLUTION: The gas-dissolved liquid generating apparatus includes: a gas-liquid mixing part 101 for mixing gas and a liquid; a microbubble generation part 104 in which the liquid containing the gas flows and the gas in the liquid is converted into microbubbles; a nanobubble generation part 105 in which the liquid containing the microbubbles flows and the microbubbles in this liquid are converted into nanobubbles; and a circulation mechanism 201 in which the liquid containing the nanobubbles circulates through the gas-liquid mixing part, the microbubble generation part and the nanobubble generation part so as to improve gas dissolution concentration in the liquid.

Description

  TECHNICAL FIELD The present invention relates to a gas solution generation apparatus and a generation method, for example, generation of nanobubble water (zeta high potential water) that contains nanobubbles and can be used as cleaning water in a semiconductor device or FPD (Flat Panel Display) manufacturing process. Applies to

At present, in the semiconductor industry and the FPD industry, chemical solutions such as SC-1 (ammonia hydrogen peroxide solution) and SC-2 (sulfuric acid hydrogen peroxide solution) are used as cleaning solutions. However, these chemical solutions have a problem of having a great influence on the environmental load when the chemical solution is discarded. Furthermore, it has been clarified that CO ₂ used to prevent static electricity deterioration that occurs in an intermediate process due to flow charging of ultrapure water (UPW) also has a significant impact on the environmental load.

  Therefore, at present, microbubble water containing bubbles called microbubbles has attracted attention as a cleaning liquid that replaces a chemical liquid. It is known that the fine bubbles present in the liquid have a charge (zeta potential) on the surface thereof. This zeta potential peels off contaminant particles from the object to be cleaned in the liquid and contributes to cleaning.

  It is also known that the zeta potential of fine bubbles in the liquid increases as the particle size decreases. On the other hand, the microbubble water currently used is mixed with bubbles having a smaller particle diameter than microbubbles called nanobubbles to large bubbles having a particle diameter of several hundreds of micrometers. Bubbles other than microbubbles are also included. The definition of microbubbles and nanobubbles is not clearly defined, but in general, microbubbles refer to bubbles with a particle size (diameter) of about 1 μm to 100 μm, and nanobubbles have a particle size (diameter) of less than 1 μm. (Refer to Patent Documents 1 and 2). Nanobubbles can be generated, for example, by irradiating microbubbles with ultrasonic waves (see Patent Document 2).

  As described above, the microbubble water includes a bubble having a small particle size that greatly contributes to cleaning to a bubble having a large particle size that has little contribution to cleaning.

  Among such large-sized bubbles, especially large-sized bubbles having a diameter of several μm or more tend to be larger bubbles by adsorbing nanobubbles and other fine bubbles. This large bubble does not convect in the liquid and collapses (collapses) near the liquid surface. Cavitation generated at the time of collapse destroys the intermediate process product and final process product of the semiconductor device and FPD. For example, the cavitation may destroy the trench structure and the fine channel on the semiconductor wafer.

  Therefore, as a cleaning liquid for semiconductor devices and FPDs, a cleaning liquid that contains as many bubbles as small as possible is desirable. Specifically, nanobubbles are contained at a high concentration, and microbubbles are removed as much as possible (that is, A cleaning solution with a low content of microbubbles is desirable.

JP 2008-36585 A JP 2006-289183 A

  As a method for cleaning a semiconductor device or FPD, for example, an ultrasonic cleaning method or an ozone dissolution method is known.

  However, in the ultrasonic cleaning method, bubbles in the order of several tens of μm are generated from fine bubbles, and the large-sized bubbles are larger by adsorbing the fine bubbles, so that the bubbles cannot be made uniform in particle size. There is. Furthermore, there is a possibility that the semiconductor device or the FPD may be damaged by ultrasonic energy or cavitation generated when the bubble collapses.

  In the ozone dissolution method, ozone is dissolved in ultrapure water, and the cleaning effect is enhanced by utilizing the activity of ozone. However, since ozone becomes stable oxygen in a short time, it is difficult to maintain a stable ozone concentration until cleaning. Moreover, when ultrapure water is charged by fluid charging, there is a risk of degrading and destroying the insulating layers of the semiconductor device and the FPD. In addition, in the ozone dissolution method, SC-1 or SC-2 may be used before using ultrapure water in which ozone is dissolved, which is no different from cleaning with a chemical solution. In addition, when ultrapure water is used, microorganisms such as bacteria that are generated in the ultrapure water when the apparatus is stopped also become a problem.

  An object of the present invention is to provide a gas solution generation apparatus and a generation method capable of generating a liquid containing nanobubbles at a high concentration and containing a small amount of microbubbles.

  One aspect of the present invention is, for example, a gas-liquid mixing unit that mixes a gas and a liquid, and microbubble generation in which the liquid containing the gas flows in and the gas contained in the liquid is converted into microbubbles. A nanobubble generating unit that converts the microbubbles contained in the liquid into nanobubbles, the liquid containing the nanobubbles, the gas-liquid mixing unit, and the microbubbles A gas dissolution liquid generation apparatus comprising: a generation unit; and a circulation mechanism that increases a gas dissolution concentration in the liquid by circulating the generation unit and the nano bubble generation unit.

  In another aspect of the present invention, for example, gas and liquid are mixed in a gas-liquid mixing unit, and the gas contained in the liquid is mixed in the microbubble generating unit into which the liquid containing the gas flows. In the nanobubble generating part into which the gas containing the microbubbles flows into the microbubbles, the microbubbles contained in the liquid are converted into nanobubbles, and the liquid containing the nanobubbles is converted into the gas-liquid mixing unit. The gas solution generation method is characterized in that it is circulated through the microbubble generation unit and the nanobubble generation unit to increase the gas dissolution concentration in the liquid.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the gas dissolution liquid production | generation apparatus and production | generation method which can produce | generate the liquid which contains nanobubble in high concentration and has little microbubble content.

It is the front view which showed the gas solution production | generation apparatus which concerns on one Embodiment of this invention. It is the side view which looked at the gas solution production | generation apparatus of FIG. 1 from the right side direction of FIG. It is the conceptual diagram which showed typically the structure of the gas solution production | generation apparatus of FIG. 4 is a graph showing the relationship between the liquid temperature and the number of microbubbles generated. It is the graph which showed the relationship between the temperature and pressure of a liquid, and gas dissolution concentration. FIG. 4 is a side cross-sectional view illustrating in detail the configuration of the microbubble generating unit in FIG. 3. FIG. 7 is an enlarged cross-sectional view showing in detail the structure of the foaming venturi tube of FIG. 6. FIG. 7 is an enlarged cross-sectional view showing in detail the structure of the foaming venturi tube of FIG. 6. It is the graph which showed distribution of the production | generation bubble in the microbubble production | generation part of FIG. FIG. 4 is a side cross-sectional view illustrating in detail the configuration of the nanobubble generating unit of FIG. 3. It is the graph which showed distribution of the production | generation bubble in the nano bubble production | generation part of FIG. It is a figure for demonstrating the structure of the conventional gas solution production | generation apparatus. It is a figure for demonstrating the structure of the gas solution production | generation apparatus of this embodiment.

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

FIG. 1 is a front view showing a gas solution generator according to an embodiment of the present invention.
FIG. 1 shows a plurality of gas inlets 121 for introducing gas from the outside of the apparatus into the gas-liquid mixing unit 101, and further includes a raw water inlet 122 serving as a raw water inlet, and generated water. A generated water outlet 123 serving as an outlet is shown.

  The gas introduced from the gas inlet 121 and the liquid (water) flowing in from the raw water inlet 122 are mixed in the gas-liquid mixing unit 101 to become a gas-dissolved solution (gas-dissolved water) in which the gas is dissolved. Next, the gas-dissolved water is agitated and mixed by an impeller rotating in the pressurizing pump 102 and is subjected to pressure, and a shear / dissolution process is performed in the shear / dissolution unit 103 to dissolve the gas by shearing.

  The gas-dissolved water that has passed through the gas-liquid mixing unit 101, the pressure pump 102, and the shear / dissolution unit 103 flows into the microbubble generation unit 104. The microbubble generating unit 104 converts the gas contained in the gas dissolved water into microbubbles. This gas-dissolved water is water containing microbubbles and is called microbubble water.

  The gas-dissolved water (microbubble water) discharged from the microbubble generation unit 104 then flows into the nanobubble generation unit 105. In the nano bubble production | generation part 105, the micro bubble contained in this gas solution water is converted into a nano bubble. This gas-dissolved water is water containing nanobubbles and is called nanobubble water.

  In the present embodiment, the gas-dissolved water (nano-bubble water) discharged from the nano-bubble generating unit 105 is converted into a gas-liquid mixing unit 101, a pressure pump 102, a shearing / dissolving unit 103, a micro-bubble generating unit 104, and a nano-bubble generating unit 105. It is possible to circulate through. In this embodiment, this gas-dissolved water is repeatedly circulated through these blocks 101 to 105 and then discharged from the generated water outlet 123 provided in the nanobubble generating unit 105 to the outside of the apparatus (for example, a water tank). Details of the circulation mechanism that performs such circulation processing will be described later.

  FIG. 1 further shows a cooler 111 that is connected to the shearing / dissolving unit 103 and cools the gas-dissolved water. Details of the cooler 111 will be described later.

FIG. 2 is a side view of the gas solution generator of FIG. 1 as viewed from the right side of FIG.
FIG. 2 shows a control panel 131 for controlling the apparatus in addition to the gas-liquid mixing unit 101, the pressure pump 102, the shearing / dissolving unit 103, the microbubble generating unit 104, the nanobubble generating unit 105, and the like. Has been.

FIG. 3 is a conceptual diagram schematically showing the configuration of the gas solution generator of FIG.
In FIG. 3, the gas introduced from the gas inlet 121 is indicated by a symbol A, and the water that flows in from the raw water inlet 122 is indicated by a symbol B. These gas and water are mixed in the gas-liquid mixing unit 101 to become gas-dissolved water.

  In this embodiment, this gas-dissolved water is repeatedly circulated by the circulation mechanism 201 via the gas-liquid mixing unit 101, the pressure pump 102, the shearing / dissolution unit 103, the microbubble generation unit 104, and the nanobubble generation unit 105. . During this time, the microbubble generator 104 generates microbubbles from the gas in the water, and the nanobubble generator 105 generates nanobubbles from the microbubbles in the water.

  FIG. 3 shows a repeat circuit 211 that constitutes the circulation mechanism 201. The repeat circuit 211 causes the gas-dissolved water (nanobubble water) discharged from the nanobubble generating unit 105 to flow into the gas-liquid mixing unit 101 again.

  Thus, in the present embodiment, the gas-dissolved water is passed through the gas-liquid mixing unit 101, the pressure pump 102, the shearing / dissolving unit 103, the microbubble generating unit 104, and the nanobubble generating unit 105 by the circulation mechanism 201. Repeat repeatedly. Thereby, the process which mixes gas and a liquid, and the process which converts this gas into a micro bubble and also a nano bubble are performed repeatedly. Furthermore, the pressurizing pump 102 and the shearing / dissolving unit 103 perform processing for further promoting mixing and dissolution. Thereby, in this embodiment, the gas dissolution concentration in gas dissolution water can be raised. In the present embodiment, such a circulation mechanism 201 can control the gas dissolution concentration in the gas dissolution water.

  In the present embodiment, the microbubble generation unit 104 further converts the gas in the dissolved gas into microbubbles, and the nanobubble generation unit 105 further converts the microbubbles into nanobubbles (two-stage process). Repeat. Thereby, the microbubble and gas which remain | survived without being converted into nanobubble by one circulation process will also be converted into nanobubble by repetition of a circulation process. As a result, the purity of the nanobubbles in water increases, and conversely, the proportion of microbubbles decreases. Therefore, according to this embodiment, it becomes possible to generate gas-dissolved water containing nanobubbles at a high concentration and having a small content of microbubbles.

  Such gas-dissolved water has an advantage that it is suitable for use as cleaning water in the manufacturing process of semiconductor devices and FPDs, for example. The reason is that this gas-dissolved water contains a high concentration of nanobubbles that contribute greatly to cleaning, has little contribution to cleaning, and has a small content of microbubbles that may damage semiconductor devices and FPD due to crushing. Because. According to this cleaning water, it is possible to suppress damage to the semiconductor device and the FPD and to improve the yield thereof.

  The time and frequency of circulating the gas-dissolved water can be changed to various times and times depending on the required gas dissolution concentration, nanobubble content, nanobubble concentration, nanobubble purity, and the size of the gas solution generator. It doesn't matter. As an example of the circulation time of the gas-dissolved water, it can be considered to be several minutes to several tens of minutes, for example, about 30 minutes.

  Moreover, the gas solution generator of this embodiment also has the following advantages.

(1) Cooling of gas-dissolved water When gas-dissolved water is circulated as in this embodiment, the temperature of the gas-dissolved water (circulating water) that circulates is the heat of reaction when microbubbles are converted into nanobubbles, or circulation. It rises due to frictional heat of water. On the other hand, it is known that the generation efficiency of microbubbles and the solubility of gas in water decrease with an increase in temperature (see FIGS. 4 and 5).

  FIG. 4 is a graph showing the relationship between the liquid temperature and the number of microbubbles generated. The horizontal axis in FIG. 4 represents the water temperature (° C.), and the vertical axis represents the number of microbubbles having a diameter of 50 μm or less (pieces / mg). The source of FIG. 4 is a product catalog material of “Nitro Muer's product“ gas-liquid shearing microbubble generator: Awataro ”(CATA-10070A-01). FIG. 4 shows the experimental result that the number of microbubbles generated decreases with increasing water temperature.

FIG. 5 is a graph showing the relationship between the liquid temperature and pressure and the gas dissolution concentration. The horizontal axis of FIG. 5 represents water pressure (10 ⁻⁵ × Pa), and the vertical axis represents the gas dissolution concentration (mg / L) of air. The source of Fig. 5 is "Generation and utilization of bubble water (IDEC Review, p.8 (1993))" by Katsuyuki Machiya et al. FIG. 5 shows measurement results of gas dissolution concentrations at various water temperatures. According to this, it can be seen that the solubility of gas in water increases as the water temperature decreases.

  Therefore, in the present embodiment, a cooler 111 is provided in the gas solution generator, and the gas dissolved water circulated by the circulation mechanism 201 is cooled by the cooler 111 (FIG. 3). This makes it possible to prevent the temperature of the circulating water from rising due to reaction heat or frictional heat. In the present embodiment, the cooler 111 makes it possible to maintain the temperature of the circulating water at an optimum temperature (for example, 4 ° C.).

In the present embodiment, the cooler 111 is connected to the shearing / dissolving unit 103. This makes it possible to increase the solubility of the circulating water during the shearing process. In this case, as shown in FIG. 3, temperature sensors T ₁ and T ₂ may be provided in the circulation mechanism 201 upstream and downstream of the shearing / dissolving unit 103, respectively. Accordingly, the water temperature (or gas temperature) is monitored by these temperature sensors T ₁ and T ₂ , and the cooler 111 can be operated as necessary based on the detected temperature. For example, it is controlled whether or not the cooler 111 is operated according to the temperature difference between the temperature detected by the temperature sensor T ₁ and the temperature detected by the temperature sensor T ₂ , or by what output the cooler 111 is operated. It becomes possible to do.

  In the present embodiment, the cooler 111 may be connected to other than the shearing / dissolving unit 103, or may be an optional product of the gas dissolved liquid generating apparatus. The cooler 111 in any of these cases corresponds to an example of the cooling means in the present invention.

(2) Gas dissolved water pressurization It is known that the solubility of gas in water is improved not only by cooling the gas dissolved water but also by pressurizing the gas dissolved water (see FIG. 5). In the present embodiment, the solubility of the gas-dissolved water during stirring and mixing can be increased by applying pressure to the gas-dissolved water by the pressure pump 102. In this embodiment, you may provide pressurization means other than the pressurization pump 102 in a gas solution production | generation apparatus.

(3) Gas introduction port The gas solution generator of this embodiment is provided with a plurality of gas introduction ports 121 for introducing gas into the gas-liquid mixing unit 101 from outside the device. When the cleaning water is generated using this apparatus, it may be desired to switch the gas for each object to be cleaned. For example, it is desirable to use hydrogen when generating cleaning water for a certain cleaning object, and it is desirable to use oxygen when generating cleaning water for another cleaning object. Condition.

  In such a case, according to the plurality of gas introduction ports 121 as in the present embodiment, it becomes possible to easily switch the gas. In addition, according to the present embodiment, not only gas-dissolved water containing a single gas but also gas-dissolved water containing a plurality of types of gases can be easily generated.

  In addition, when producing | generating a gas solution using multiple types of gas or multiple types of liquid, as a structure of the shearing / dissolving part 103, what is described in patent 4094633 and patent 3762206 is employ | adopted, for example. Is desirable. As a result, it is possible to simultaneously apply a physical force to the two phases of liquid and gas, and to generate gas-dissolved water containing fine bubbles.

(4) Surplus gas reintroduction port In the gas solution generator of this embodiment, as shown in FIG. 3, surplus gas generated from the gas dissolved water in this device is reintroduced into the gas-liquid mixing unit 101. A surplus gas reintroduction port 124 is provided. Thereby, in this embodiment, it becomes possible to recycle surplus gas, and it is possible to make the apparatus ecologically superior without wastefully discarding surplus gas.

  In the present embodiment, the surplus gas generated in the microbubble generating unit 104 is reintroduced from the surplus gas reintroduction port 124. FIG. 3 shows a return circuit 212 for reintroducing surplus gas from the microbubble generating unit 104 into the gas-liquid mixing unit 101 via the surplus gas reintroduction port 124.

(5) Eco circuit The generated water (nano bubble water) generated in the present embodiment is discharged from the generated water outlet 123 to the outside of the apparatus, and is used for cleaning semiconductor devices and FPDs, for example. In FIG. 3, these cleaning objects are shown as loads 141. By washing the load 141 using the generated water, particles are peeled off from the object to be cleaned.

  In the present embodiment, for example, an eco circuit 213 including a particle separation unit 142 and a particle filter 143 may be optionally attached to the gas solution generation apparatus. The particle separation unit 142 separates particles from the object to be cleaned after cleaning, and the particle filter 143 filters the cleaning water from which the particles are separated, and removes particles in the cleaning water.

  Water that has passed through the eco circuit 213 may be discharged by the water discharge circuit 214 or may flow again into the raw water inlet 212 by the recovery circuit 215. According to the former, it is possible to avoid discharging water while it is dirty, and according to the latter, water can be reused, and the apparatus can be made ecologically superior.

(6) Specific examples of gases, liquids, objects to be cleaned, and cleaning treatment Note that specific examples of gases used include hydrogen (H ₂ ), oxygen (O ₂ ), nitrogen (N ₂ ), and ammonia (NH ₃ ). Etc. Specific examples of the liquid to be used include ultrapure water, alkaline ionized water, seawater and the like.

  Specific examples of objects to be cleaned include semiconductor wafers, ceramic wafers, magnetic disk substrates, optical disk substrates, glass substrates for photomasks, glass substrates for plasma displays, glass substrates for liquid crystal display devices, and the like. Examples include various substrates. Further, specific examples of the cleaning treatment include removal of metal impurities and removal of organic contaminants.

  Hereinafter, the configuration of the microbubble generation unit 104 and the nanobubble generation unit 105 of FIG. 3 will be described in detail.

(Microbubble generator)
FIG. 6 is a side sectional view showing in detail the configuration of the microbubble generator 104 of FIG.

  As shown in FIG. 6, the microbubble generating unit 104 includes a microbubble generating unit main body (foaming chamber) 301, a gas dissolved water inlet 302, a foaming venturi tube 303, an excess gas outlet 304, and an excess gas return tube. 305 and a microbubble water outlet 306.

  In the microbubble generation unit 104, the gas dissolved water flows into the microbubble generation unit main body 301 from the gas dissolved water inlet 302 through the foaming venturi tube 303. The microbubble generating unit main body 301 is a foaming chamber that can accommodate dissolved gas water. Each of the foaming venturi tubes 303 individually injects gas-dissolved water into the foaming chamber 301 to generate microbubbles in the foaming chamber 301.

  The micro-bubble generating unit 104 of the present embodiment is provided with a plurality of small and small-capacity foaming venturi tubes 303, and the required ability can be obtained by increasing the number of foaming venturi tubes 303. ing. In this embodiment, the amount of foaming per Venturi tube is made small, and the desired amount of foaming is increased by increasing the number of Venturi tubes, thereby generating microbubbles having a uniform and small variation in particle size. It becomes possible. Further, by making each Venturi tube small and small in capacity, it becomes possible to generate fine and stable microbubbles.

  Further, in the present embodiment, the foaming chamber 301 has a shape that is long in the vertical direction, and the foaming venturi tube 303 is foamed so as to inject gas-dissolved water toward the upper part (top) of the foaming chamber 301. It is installed upward at the bottom of the chamber 301. FIG. 6 shows a foam control zone located above the foaming venturi tube 303 in the foaming chamber 301 and a gas-liquid mixture zone formed further above the foam control zone. The gas-dissolved water is converted into a bubble flow having a microbubble diameter in the foaming venturi tube 303, and becomes a foamed flow toward the bubble regulating zone. FIG. 6 shows how the foaming flow circulates within the foaming chamber 301.

  Here, the structure and advantages of the foaming chamber 301 will be described in detail.

  Microbubbles are generally generated by injecting gas-dissolved water into a water tank or the like. However, this method has a disadvantage that the variation in the generated bubble diameter is large. On the other hand, in this embodiment, the foaming chamber 301 independent of the water tank outside the device is provided separately in the device, and microbubbles are generated in the foaming chamber 301. Thereby, in this embodiment, it becomes possible to prevent the diffusion of microbubbles and the randomization of the generated bubble diameter resulting therefrom.

  In particular, the bubble regulating zone of the foaming chamber 301 contributes to such an effect. In the present embodiment, a foam regulating zone having a certain capacity is provided above the foaming venturi tube 303 in the foaming chamber 301. Without this zone, the generated bubbles move freely and the bubble diameter increases. In the present embodiment, it is possible to suppress the variation in the generated bubble diameter by providing the bubble regulating zone at the upper part of the foaming venturi tube 303.

In FIG. 6, the upper surface of the foaming chamber 301 is indicated by S ₁ , and the side surface of the foaming chamber 301 is indicated by S ₂ . In this embodiment, the surplus gas outlet 304 is provided on the upper surface S ₁ of the foaming chamber 301, and the microbubble water outlet 306 is provided on the side surface S ₂ of the foaming chamber 301.

In the foaming chamber 301, a gas-liquid mixture zone is formed in the upper part of the bubble regulating zone by the surplus gas generated from the gas dissolved water. Therefore, in the present embodiment, the surplus gas outlet 304 is provided on the upper surface S ₁ of the foaming chamber 301, and the surplus gas is discharged from the surplus gas outlet 304. By providing the surplus gas outlet 304 on the upper surface S ₁ instead of the side surface S ₂ of the foaming chamber 301, it is possible to discharge only the surplus gas out of the surplus gas and the dissolved gas water from the surplus gas outlet 304. Yes.

  The surplus gas outlet 304 is connected to the return circuit 212 and the surplus gas reintroduction port 124 shown in FIG. 3 through the surplus gas return tube 305. Therefore, the surplus gas discharged from the surplus gas outlet 304 is reintroduced into the gas-liquid mixing unit 101. Thereby, in this embodiment, it becomes possible to recycle surplus gas, and it is possible to make the apparatus ecologically superior without wastefully discarding surplus gas.

  On the other hand, the generated microbubble group is discharged from the microbubble water outlet 306 as microbubble water containing the microbubble group. The microbubble water outlet 306 is provided at the substantially central part of the most stable foaming chamber 301 of the microbubble group. Microbubble water discharged from the microbubble water outlet 306 will flow into the nanobubble generator 105. The microbubble water outlet 306 corresponds to a specific example of the liquid outlet in the present invention.

  In this embodiment, the storage time of the generated microbubble group is provided, and the stabilized microbubble group is sent to the nanobubble generating unit 105. It is known that microbubbles having a diameter of about 65 μm or more do not become nanobubbles. Therefore, in this embodiment, the microbubble generating unit 104 is configured so that many microbubbles having a diameter of about 65 μm or less are generated.

  Next, the structure of the foaming venturi tube 303 will be described in detail.

  7 and 8 are enlarged cross-sectional views showing in detail the structure of the foaming venturi tube 303 of FIG.

  As shown in FIG. 7, the shape of the inner wall surface of the foaming venturi tube 303 is once narrowed and then widened again from the gas-dissolved water inlet 302 toward the injection port, and the shape using Bernoulli's theorem is It has become.

In FIG. 7, the inner wall surface of the injection port of the foaming venturi tube 303 is indicated by S ₃ , and the injection direction of the gas dissolved water by the foaming venturi tube 303 is indicated by D. The shape of the inner wall surface S ₃ of the injection port of the foaming venturi 303 is shown in detail in FIG. In the present embodiment, the inner wall surface S ₃ of the injection port of the foaming venturi tube 303 is widened at an angle of 5 degrees to 10 degrees with respect to the injection direction D. This makes it possible to circulate the foam flow in various directions and stabilize the generated bubbles.

  In the present embodiment, the microbubble generating unit 104 may be provided with foaming means other than the foaming venturi tube 303. For example, a plurality of orifice type foaming nozzles other than the foaming venturi tube 303 may be provided in the microbubble generating unit 104.

  As described above, according to the microbubble generation unit 104 of this embodiment, it is possible to generate microbubbles that are fine, stable, and uniform. FIG. 9 is a graph showing the distribution of generated bubbles in the microbubble generating unit 104 of FIG. Thus, the distribution of the generated bubbles in this embodiment shows a uniform mountain distribution and becomes a cloudy distribution. It should be noted that in this distribution, the number of microbubbles having a diameter of 65 μm or more is small.

(Nano bubble generator)
FIG. 10 is a side sectional view showing in detail the configuration of the nanobubble generator 105 of FIG.

  As shown in FIG. 10, the nanobubble generating unit 105 includes a nanobubble generating unit main body (accommodating chamber) 401, an ultrasonic transducer 402, a microbubble water inlet 403, a guide channel 404, an isolation wall tube 405, It has a microbubble water discharge part 406, a repeat water outlet 407, a nanobubble water outlet 408, a contaminant separation water outlet 409, a baffle plate 410, and a corrugated part 411.

Microbubble water (gas dissolved water) generated by the microbubble generator 104 is introduced from the microbubble water inlet 403 to the nanobubble generator main body 401 through the guide channel 404 and released. The nanobubble generation unit main body 401 is a storage chamber that can store microbubble water. The guide channel 404 has an open end P provided on the bottom of the storage chamber 401, the open end P is placed downward in the vicinity of the bottom surface of the receiving chamber 401 shown in S ₆ . Therefore, the microbubble water from the microbubble generating unit 104 is introduced to the open end P through the guide channel 404 and discharged to the bottom of the storage chamber 401.

  It is known that microbubbles become nanobubbles by spontaneously or forcibly collapsing (crushing). The former crush is called self-crush, and the latter is called forced crush. It is also known that there is a crushing method using ultrasonic vibration energy as one of the methods for forcibly crushing microbubbles. The ultrasonic transducer 402 according to the present embodiment irradiates the microbubble water in the accommodation chamber 401 with ultrasonic waves to crush the microbubbles into nanobubbles. Thereby, in this embodiment, it becomes possible to produce the crushing phenomenon of microbubbles instantly without taking a long time. In FIG. 10, the ultrasonic wave emitted from the ultrasonic transducer is indicated by the symbol W.

  Here, the configuration of the ultrasonic transducer 402 of the present embodiment will be described in detail.

  In the nanobubble generating unit 105 of the present embodiment, a plurality of ultrasonic transducers 402 having different vibration frequencies are provided, and these ultrasonic transducers 402 vibrate at different frequencies. Depending on the particle size of the microbubbles, the ultrasonic frequency at which they are easily crushed may differ. In this embodiment, it is possible to cope with variations in the crushing reaction due to the difference in the particle size of the microbubbles by generating ultrasonic waves of a plurality of frequencies simultaneously or sequentially in the storage chamber 401.

  Therefore, according to the present embodiment, microbubbles having various particle diameters can be smoothly collapsed into nanobubbles, which makes it possible to achieve uniformization and stabilization of nanobubbles. Further, according to the present embodiment, by selecting the vibration frequency and output of the ultrasonic transducer 402, it is possible to control the particle size and number of generated nanobubbles, and generate a large amount of fine nanobubbles. It is also possible.

  Since the ultrasonic transducer 402 is relatively small and inexpensive, there is an advantage that even if a plurality of ultrasonic transducers 402 are arranged, it does not take up much space and costs. For example, when there is a gas or liquid that does not collapse smoothly unless the ultrasonic frequency is changed, it is convenient to have a plurality of ultrasonic transducers 402 having different vibration frequencies (microbubbles are Bjerknes). It is known that there is a case where it does not collapse even when irradiated with ultrasonic waves due to the influence of force). Examples of the vibration frequency of the ultrasonic transducer 402 include 430 kHz, 850 kHz, 28 kHz, and 1 MHz.

  In the nanobubble generation unit 105 of the present embodiment, a plurality of ultrasonic transducers 402 are provided as ultrasonic vibration means, but only one ultrasonic transducer 402 may be provided.

  Next, the arrangement of the ultrasonic transducer 402 and the like according to this embodiment will be described in detail.

  In the present embodiment, the ultrasonic transducer 402 is installed at the bottom of the storage chamber 401 and irradiates ultrasonic waves toward the top of the storage chamber 401. In addition, the storage chamber 401 has a shape that is long in the vertical direction, like the foaming chamber 301 of the microbubble generating unit 104.

On the other hand, the open end P of the guide channel 404 is provided near the bottom surface S ₆ of the storage chamber 401 as described above. In the present embodiment, the isolation wall tube 405 is further interposed at the bottom of the storage chamber 401 between the open end P of the guide channel 404 and the ultrasonic transducer 402 and extends upward from the bottom surface S _6. An isolation wall tube 405 is provided so as to surround the guide channel 404 in a cylindrical shape. Thereby, in this embodiment, an ultrasonic wave does not hit microbubble water immediately after being introduced into the bottom part of the storage chamber 401. The isolation wall (isolation wall tube) 405 has a tubular shape in this embodiment, but may have other shapes.

  The microbubble water introduced into the bottom of the storage chamber 401 does not go laterally by the isolation wall tube 405 but rises so that bubbles do not flow immediately above the ultrasonic transducer 402. It has become.

  A group of microbubbles in the microbubble water passes through the isolation wall tube 405 and gathers in the upper region. In FIG. 10, this region is shown as an ultrasonic irradiation zone. The ultrasonic wave emitted from the ultrasonic transducer 402 travels upward outside the isolation wall tube 405 and is irradiated to the microbubble group in this ultrasonic wave irradiation zone. These microbubbles are crushed by being irradiated with ultrasonic waves and converted into nanobubbles. In this embodiment, by providing such an ultrasonic irradiation zone, it is possible to efficiently perform ultrasonic irradiation to the microbubble group.

  In the present embodiment, a microbubble water discharge unit 406 is provided at the bottom of the storage chamber 401 so as to be surrounded by the isolation wall tube 405. The microbubble water discharge unit 406 can be used when it is desired to take out the microbubble water from the circulation mechanism 201 shown in FIG. The microbubble water introduced into the bottom of the storage chamber 401 is discharged out of the storage chamber 401 as the microbubble water discharge portion 406 is opened.

  Next, the structure of the storage chamber 401 will be described in detail.

In FIG. 10, the upper surface of the storage chamber 401 is indicated by S ₄ , and the side surface of the storage chamber 401 is indicated by S ₅ . In the present embodiment, the repeat water outlet 407 and the nano bubble water outlet 408 are provided on the side surface S ₅ of the housing chamber 401, the contaminants separated water outlet 409, the side surface S ₅ of the housing chamber 401, repeat water outlet 407 Or the nanobubble water outlet 408.

  The generated nanobubble group is discharged from the repeat water outlet 407 and the nanobubble water outlet 408 as nanobubble water containing the nanobubble group.

  From the repeat water outlet 407, the nanobubble water is discharged into the circulation mechanism 201 shown in FIG. The nanobubble water discharged from the repeat water outlet 407 flows into the gas-liquid mixing unit 101 via the repeat circuit 211. Thus, the nanobubble water circulates in the circulation mechanism 201. Thereby, the gas dissolution concentration in nanobubble water is raised. Furthermore, the purity of the nanobubbles in the nanobubble water is increased, and conversely, the proportion of microbubbles in the nanobubble water decreases. The repeat water outlet 407 corresponds to a specific example of the first liquid outlet in the present invention.

  On the other hand, nanobubble water is discharged out of the circulation mechanism 201 shown in FIG. 3 from the nanobubble water outlet 408. The nanobubble water discharged from the nanobubble water outlet 408 is discharged, for example, to a water tank outside the apparatus. In the present embodiment, the nanobubble water is repeatedly circulated in the circulation mechanism 201 and then discharged from the nanobubble water outlet 408. Thereby, in this embodiment, nanobubble water can be provided in high concentration, and nanobubble water with little microbubble content can be provided. The nanobubble water outlet 408 corresponds to a specific example of the second liquid outlet in the present invention. The nanobubble water outlet 408 is shown as the generated water outlet 123 in FIG.

  In this embodiment, the repeat water outlet 407 and the nanobubble water outlet 408 are disposed on the side of the isolation wall pipe 406 and are located below the upper end of the isolation wall pipe 406. Therefore, the nanobubble water which goes to these outflow ports 407 and 408 passes through the outside of the isolation wall tube 406 and reaches these outflow ports 407 and 408.

  Accordingly, the nanobubble water toward the outlets 407 and 408 reaches the outlets 407 and 408 without being mixed with the microbubble water inside the isolation wall tube 406. A small amount of nanobubble water is discharged.

  In addition, the nanobubble water toward the outlets 407 and 408 remains after the microbubbles are crushed into nanobubbles in the ultrasonic irradiation zone, and then reach the outlets 407 and 408 through the ultrasonic transducer 402. Many of the microbubbles are also crushed by nanobubbles. Thereby, the nano bubble water discharged | emitted from the outflow port 407,408 becomes nano bubble water with few crushing collapse of a micro bubble.

  The ultrasonic transducer 402 is disposed at the bottom of the storage chamber 401, the isolation wall tube 405 is interposed between the open end P of the guide channel 404 and the ultrasonic transducer 402, and the outlets 407 and 408 are connected to the isolation wall tube. Arranging on the side of 406 has these advantages. That is, with such an arrangement, it is possible to discharge nanobubble water with a small content of microbubbles from the outlets 407 and 408.

  Note that the ultrasonic transducer 402 is desirably arranged near the outlets 407 and 408 in order to reduce the collapse of the microbubbles near the outlets 407 and 408.

A contaminant separation water outlet 409 is further provided on the side surface S ₅ of the storage chamber 401. In FIG. 10, contaminants such as impurities and fine particles that have floated inside the storage chamber 401 are indicated by a symbol X. When these contaminants are contained in the nanobubble water, it reacts with the charge on the surface of the nanobubbles, which causes a decrease in the zeta potential of the nanobubbles. Thus, the contaminants in the nanobubble water have a negative effect on the nanobubbles.

Therefore, in the present embodiment, the contaminant separation water outlet 409 is provided on the side surface S ₅ of the storage chamber 401. Thereby, in this embodiment, it becomes possible to isolate | separate contaminants from the remaining nanobubble water by discharging | emitting the nanobubble water containing the floated contaminant from the contaminant separation water exit 409. FIG. Contaminants separated water outlet 409, so as to easily remove contaminants that emerged, it is preferably provided near the upper surface S ₄ of the accommodation room 401.

  When ultrasonic waves are irradiated to microbubbles, a crushing phenomenon usually occurs. However, by controlling the frequency and output of the ultrasonic waves to be irradiated, the microbubbles can be brought close to each other without being crushed (patent document). 1). By utilizing this property, by irradiating the microbubble with an ultrasonic wave that does not cause a crushing phenomenon, the microbubble and the contaminant can be brought close to each other and the contaminant can be adsorbed to the microbubble. Thereby, it becomes possible to give buoyancy to the pollutant and to float the pollutant.

  Therefore, in this embodiment, it is desirable to provide the nanobubble generating unit 105 with an ultrasonic transducer 402 that generates ultrasonic waves having a frequency that does not cause a crushing phenomenon. Thereby, it becomes possible to float a contaminant by such an ultrasonic wave, As a result, it becomes easy to remove a contaminant from the contaminant separation water outlet 409.

  Next, the baffle plate 410 and the corrugated part 411 will be described in detail.

The baffle plate 410 is made of, for example, a fine mesh wire net. As shown in FIG. 10, the baffle plate 410 is installed almost horizontally below the upper surface S ₄ of the storage chamber 401 by a distance H ₁ in the storage chamber 401. Here, the distance H ₁ is about ¼ of the distance H from the upper surface S ₄ to the bottom surface S ₆ of the accommodation chamber. The baffle plate 410 may be formed of a mesh member other than the wire mesh.

  The microbubbles rise in the ultrasonic irradiation zone and collide with the baffle plate 410, so that the self-crushing is promoted. Thus, according to the baffle plate 410, the self-collapse of the microbubbles is promoted, and the collapse of the microbubbles is reduced.

  On the other hand, when the microbubble collides with the baffle plate 410, the microbubble may not be self-collapsed. That is, the microbubbles bounce off the baffle plate 410 in various directions. As a result, there is a high possibility that microbubbles at positions that are difficult to be irradiated with ultrasonic waves will rebound to positions where ultrasonic waves are easily irradiated due to random reversal.As a result, the irradiation efficiency of ultrasonic waves is improved, and Less crushing leaks.

In addition, a corrugated portion 411 is formed on the upper surface S ₄ of the storage chamber 401 as shown in FIG. As a result, the upper surface S ₄ of the storage chamber 401 is not flat, but is a corrugated uneven surface. As a result, the ultrasonic wave traveling toward the upper surface S ₄ in the accommodation chamber 401 is irregularly reflected on the upper surface S ₄ . As a result, the ultrasonic waves are uniformly applied to the microbubbles in the storage chamber 401. As a result, the irradiation efficiency of the ultrasonic waves is improved and the collapse of the microbubbles is reduced.

  As described above, the baffle plate 410 and the corrugated portion 411 have an effect of reducing the collapse of the microbubbles.

  Next, members forming the storage chamber 401 and the guide channel 404 will be described in detail.

In Figure 10, the point from the top surface S ₄ by a distance H ₁ lower accommodation chamber 401 is indicated by P _1, point from the bottom S ₆ by a distance H ₂ above the storage chamber 401 is indicated by P _2. The distances H ₁ and H ₂ are both about ¼ of the distance H from the upper surface S ₄ to the bottom surface S ₆ of the storage chamber.

Further, in FIG. 10, the region from P ₁ to P _{2 in} the side surface S ₅ of the storage chamber 401 is indicated by a symbol R.

  In the present embodiment, the region R is a transparent member region (transparent tube) formed of a transparent member such as quartz glass. Thereby, the inside of the storage chamber 401 can be seen from the outside of the storage chamber 401. This has the advantage that it is possible to monitor the generation of nanobubbles from microbubbles.

The transparent member region R may be provided at a position different from the position shown in FIG. 10 on the side surface S ₅ of the storage chamber 401. However, it is desirable to provide the transparent member region R at a position where the ultrasonic irradiation zone can be visually observed so that the nanobubbles can be monitored.

  In the present embodiment, the guide channel 404 is formed entirely or partially by a transparent member such as quartz glass. Thereby, the inside of the guide channel 404 can be visually observed from the outside of the storage chamber 401 through the transparent member region R. This has the advantage that the state of the incoming microbubble water can be monitored.

  When the guide channel 404 is partially formed of a transparent member, a portion of the guide channel 404 that is visible from the transparent member region R is formed of a transparent member. For example, only a portion of the guide channel 404 located inside the storage chamber 401 is formed of a transparent member. In this case, the entire portion located inside the storage chamber 401 may be formed of a transparent member, or only a part thereof may be formed of a transparent member.

  According to the storage chamber 401 and the guide channel 404 as described above, there is an advantage that a malfunction occurring in the storage chamber 401 can be quickly detected. In addition, it is possible to capture the state in the storage chamber 401 with a camera or the like instead of visual observation, so that the state in the storage chamber 401 can be photographed and recorded. In general, since microbubble water becomes cloudy and nanobubble water becomes transparent, when the inside of the storage chamber 401 is visually observed from the transparent member region R, the microbubble water in the guide channel 404 and the storage are stored. The nanobubble water in the chamber 401 can be distinguished visually.

  Note that the ultrasonic transducer 402 of the nanobubble generating unit 105 can be used for generating cavitation in nanobubble water and for degassing.

  In addition, the nanobubble generating unit 105 of the present embodiment is used not only for generating cleaning water but also for generating high-capacity sterilizing water (in this case, the gas is ozone) and for photocatalytic reaction (sonochemistry principle). Is possible. Also in these cases, the effect of the circulation mechanism 201 of the present embodiment in which the concentration of nanobubbles in the nanobubble water is increased and the content of microbubbles is reduced is useful.

  As described above, according to the nanobubble generation unit 105 of the present embodiment, it is possible to generate fine, uniform and durable nanobubbles. FIG. 11 is a graph showing the distribution of generated bubbles in the nanobubble generating unit 105 of FIG. It should be noted that in this distribution, the number of nanobubbles with a diameter of 100 nm is overwhelmingly larger than the number of nanobubbles with a diameter of 200 nm or 400 nm.

(Cleaning effect of nano bubble water)
Hereinafter, the cleaning effect of nanobubble water will be described, and further, the excellent cleaning effect of nanobubble water generated in the present embodiment will also be described.

  The cleaning effect of nanobubble water is first attributed to the zeta potential of nanobubbles.

  As described above, it is known that the fine bubbles present in the liquid have a charge (zeta potential) on the surface thereof. This zeta potential peels particles from the object to be cleaned in the liquid and contributes to cleaning. It is known that the zeta potential of fine bubbles in the liquid increases as the particle size decreases.

  Therefore, nanobubbles having a particle size smaller than that of microbubbles greatly contribute to cleaning. The nanobubble water generated in this embodiment is suitable as washing water because it contains nanobubbles at a high concentration. The nanobubble water generated in the present embodiment is zeta high potential water containing nanobubbles that are bubbles having a high zeta potential at a high concentration.

  In addition, from the viewpoint of the cleaning effect by the zeta potential, the particle size (diameter) of the nanobubbles is desirably in the range of 50 to 100 nm. According to this embodiment, as can be seen from FIG. 11, it is possible to generate nanobubble water containing nanobubbles having such a particle size at a high concentration.

  Secondly, the cleaning effect of the nanobubble water is attributed to radicals contained in the nanobubble water.

  When microbubbles are crushed into nanobubbles, some of the surrounding water molecules are decomposed, and H radicals and OH radicals are temporarily generated. These radicals act to remove particles from the object to be cleaned by causing an oxidation-reduction reaction with the particles of particles adhering to the object to be cleaned to inactivate them or breaking the bond between the particles. This is the principle of radical cleaning. Radical cleaning has a cleaning power 100 to 1000 times that of ultrasonic cavitation cleaning.

  In the present embodiment, nanobubbles are generated by a two-stage process in which gas in the gas-dissolved water is converted into microbubbles, and the microbubbles are further converted into nanobubbles. And in order to crush a microbubble when producing | generating this nanobubble, the nanobubble water produced | generated by this embodiment contains a radical. Therefore, the nanobubble water produced | generated by this embodiment is a thing suitable as washing water also from this viewpoint.

From the viewpoint of radical cleaning, the gas used is preferably hydrogen (H ₂ ). The reason is that the reaction between OH radicals and H ₂ doubles the total number of radicals and doubles the detergency of nanobubble water.

  When performing radical cleaning, for example, the storage chamber 401 of the nanobubble generating unit 105 may be a cleaning chamber that stores a cleaning target and performs cleaning. This makes it possible to perform cleaning before the radicals generated temporarily disappear.

  As described above, the zeta potential and radicals contribute to the cleaning effect of nanobubble water. On the other hand, microbubbles contained in nanobubble water have undesirable effects on them when cleaning semiconductor devices and FPDs. May cause effects. The reason is that the collapse of the microbubbles may damage the semiconductor device and the FPD.

  On the other hand, although the nanobubble water produced | generated by this embodiment contains nanobubble in high concentration, there is little content of microbubble. Therefore, the nanobubble water produced | generated by this embodiment is a thing suitable as washing water also from this viewpoint.

(Comparison between this embodiment and a conventional gas solution generator)
Here, the structure of this embodiment and the conventional gas solution production | generation apparatus is compared.

FIG. 12 is a diagram for explaining the configuration of a conventional gas solution generator.
In the conventional gas solution generator, for example, as shown in FIG. 12, the foaming nozzle is directly attached to the side surface of the water tank (storage tank), and the gas dissolved water is jetted into the water tank, so that Generate microbubbles. Then, these microbubbles are crushed into nanobubbles by an ultrasonic vibrator attached to the water tank.

  Such an apparatus has a problem that the distribution and concentration of microbubbles, and further, the distribution and concentration of nanobubbles cannot be made uniform. The distribution and concentration of microbubbles and nanobubbles in this case vary depending on the conditions of the aquarium, such as the volume of the aquarium, the distance between the water surface and the bottom surface, and the distance between the wall surfaces, that is, the location of the bubble jet (use) The particle size of the generated bubbles will be scattered. Moreover, since the diffusion region of the microbubbles is expanded, the irradiation efficiency of ultrasonic waves is deteriorated.

  On the other hand, the gas solution generator of this embodiment has the following advantages. FIG. 13 is a diagram for explaining the configuration of the gas solution generation apparatus of the present embodiment.

  First, in this embodiment, the microbubble generation part 104 is provided in the gas dissolution liquid production | generation apparatus separately from the water tank 151, and it has a bubble regulation zone in it. In the present embodiment, microbubbles are generated not in the water tank 151 but in the bubble regulating zone in the microbubble generator 104. This makes it possible to make the distribution and concentration of microbubbles uniform.

  Further, in the present embodiment, the collapse from the microbubbles to the nanobubbles is caused not in the water tank 151, but also in the microbubble generation unit 104, and in the nanobubble generation unit 105 provided separately from these. ing. This makes it possible to make the distribution and concentration of nanobubbles uniform. Moreover, according to this embodiment, since the microbubble diffusion region can be limited, the irradiation efficiency of ultrasonic waves is improved, and an energy-saving device can be realized.

  In addition, when microbubbles are made into nanobubbles in the water tank 151, cavitation ecological damage may occur depending on the type of gas solution, but in this embodiment, nanobubble generation is provided separately from the water tank 151. In addition, since it is generated in the nanobubble generator 105, this problem can be suppressed.

  In the present embodiment, the gas-dissolved water is repeatedly circulated through the gas-liquid mixing unit 101, the microbubble generating unit 104, the nanobubble generating unit 105, and the like by the circulation mechanism 201 to increase the gas dissolution concentration in the gas-dissolved water. . Thereby, in this embodiment, nanobubble can be contained in high concentration and the gas dissolution water with little content of microbubbles can be produced | generated.

(Effects of the gas solution generator of this embodiment)
Finally, the effect of the gas dissolved liquid production | generation apparatus of this embodiment is demonstrated.

  As described above, in the present embodiment, the gas-dissolved water is passed through the gas-liquid mixing unit 101, the pressure pump 102, the shearing / dissolving unit 103, the microbubble generating unit 104, and the nanobubble generating unit 105 by the circulation mechanism 201. And circulate repeatedly. Thereby, the process which mixes gas and a liquid, and the process which converts this gas into a micro bubble and also a nano bubble are performed repeatedly. Furthermore, the pressurizing pump 102 and the shearing / dissolving unit 103 perform processing for further promoting mixing and dissolution. Thereby, in this embodiment, the gas dissolution concentration in gas dissolution water can be raised.

  In the present embodiment, the microbubble generation unit 104 further converts the gas in the gas-dissolved water into microbubbles, and the nanobubble generation unit 105 repeatedly converts the microbubbles into nanobubbles. . Thereby, the microbubble and gas which remain | survived without being converted into nanobubble by one circulation process will also be converted into nanobubble by repetition of a circulation process. Therefore, according to this embodiment, it becomes possible to generate gas-dissolved water containing nanobubbles at a high concentration and having a small content of microbubbles.

  Such gas-dissolved water has an advantage that it is suitable for use as cleaning water in the manufacturing process of semiconductor devices and FPDs, for example. The reason is that this gas-dissolved water contains a high concentration of nanobubbles that contribute greatly to cleaning, has little contribution to cleaning, and has a small content of microbubbles that may damage semiconductor devices and FPD due to crushing. Because. According to this cleaning water, damage to the semiconductor device and the FPD can be suppressed, and the yield of these can be improved.

  Further, in the present embodiment, the microbubble generating unit 104 having the structure shown in FIG. 6 can generate fine, stable, and uniform microbubbles. Furthermore, the nanobubble generator 105 having the structure shown in FIG. 10 can generate fine, uniform and durable nanobubbles from such microbubbles. Thereby, in this embodiment, it is possible to generate gas dissolved water (zeta high-potential water) that contains fine and uniform nanobubbles with a high concentration at a high concentration and is more suitable as cleaning water.

  As mentioned above, although the example of the specific aspect of this invention was demonstrated by embodiment of this invention, this invention is not limited to the said embodiment.

DESCRIPTION OF SYMBOLS 101 Gas-liquid mixing part 102 Pressure pump 103 Shearing / dissolution part 104 Micro bubble production | generation part 105 Nano bubble production | generation part 111 Cooling machine 121 Gas inlet 122 Raw water inlet 123 Generated water outlet 124 Excess gas reintroduction inlet 131 Control panel 141 Load 142 Particles Separator 143 Particle filter 151 Water tank 201 Circulation mechanism 211 Repeat circuit 212 Return circuit 213 Eco circuit 214 Water discharge circuit 215 Recovery circuit 301 Microbubble generator main body (foaming chamber)
302 Gas dissolved water inlet 303 Venturi tube for foaming 304 Surplus gas outlet 305 Surplus gas return tube 306 Microbubble water outlet (liquid outlet)
401 Nanobubble generator body (container)
402 Ultrasonic vibrator 403 Micro bubble water inlet 404 Guide channel 405 Separation wall tube 406 Micro bubble water discharge part 407 Repeat water outlet (first liquid outlet)
408 Nanobubble water outlet (second liquid outlet)
409 Pollutant separation water outlet 410 Baffle plate 411 Corrugated part

Claims (20)

A gas-liquid mixing section for mixing gas and liquid;
The liquid containing the gas flows in, and a microbubble generating unit that converts the gas contained in the liquid into microbubbles;
The liquid containing the microbubbles flows in, a nanobubble generating unit that converts the microbubbles contained in the liquid into nanobubbles,
A circulation mechanism that increases the gas dissolution concentration in the liquid by circulating the liquid containing the nanobubbles through the gas-liquid mixing unit, the microbubble generation unit, and the nanobubble generation unit,
A gas solution generator characterized by comprising: The nanobubble generator is
A storage chamber capable of storing the liquid;
Ultrasonic vibration means for irradiating the liquid in the storage chamber with ultrasonic waves to change the microbubbles to the nanobubbles;
The gas solution generator according to claim 1, comprising:   The gas solution generator according to claim 2, wherein the ultrasonic vibration means includes a plurality of ultrasonic vibrators having different vibration frequencies.   4. The gas solution generator according to claim 2, wherein the ultrasonic vibration means is provided at a bottom portion of the storage chamber and irradiates the ultrasonic wave toward an upper portion of the storage chamber. 5. . The nanobubble generator further includes
A guide channel having an open end provided at the bottom of the storage chamber and introducing the liquid to the open end;
An isolation wall interposed between the open end of the guide channel and the ultrasonic wave generation means, and extending upward from the bottom surface of the storage chamber;
The gas solution generator according to claim 4, comprising: The nanobubble generator further includes
A first liquid outlet provided on a side surface of the storage chamber for discharging the liquid containing the nanobubbles into the circulation mechanism;
A second liquid outlet provided on a side surface of the storage chamber for discharging the liquid containing the nanobubbles out of the circulation mechanism;
A pollutant separation liquid outlet that is provided above the first and second liquid outlets on the side surface of the storage chamber and discharges the liquid containing the floating contaminants;
The gas solution generator according to any one of claims 2 to 5, wherein the gas solution generator is provided.   The nano-bubble generating unit is further formed of a mesh-like member, and further includes a baffle plate disposed below the upper surface of the storage chamber by a predetermined distance in the storage chamber. The gas solution production | generation apparatus of any one.   The gas solution generator according to any one of claims 2 to 7, wherein an uneven surface for irregularly reflecting the ultrasonic waves is formed on an upper surface of the storage chamber.   The gas solution generator according to any one of claims 2 to 8, wherein a transparent member region formed of a transparent member is provided on a side surface of the storage chamber.   6. The gas solution generator according to claim 5, wherein the guide channel is formed entirely or partially by a transparent member.   The gas solution generator according to any one of claims 1 to 10, further comprising cooling means for cooling the liquid circulated by the circulation mechanism.   The gas solution generator according to any one of claims 1 to 11, further comprising a pressurizing unit that pressurizes the liquid circulated by the circulation mechanism. Furthermore,
A plurality of gas inlets for introducing the gas from outside the generator into the gas-liquid mixing unit;
A surplus gas reintroduction port for reintroducing surplus gas generated from the liquid in the generator into the gas-liquid mixing unit;
The gas solution generator according to any one of claims 1 to 12, further comprising:   The gas solution generator according to claim 13, wherein the surplus gas generated in the microbubble generating unit is reintroduced from the surplus gas reintroduction port. The microbubble generator is
A foaming chamber capable of containing the liquid;
Foaming means for injecting the liquid into the foaming chamber and generating the microbubbles in the foaming chamber;
The gas solution generator according to any one of claims 1 to 14, characterized by comprising:   16. The gas solution generator according to claim 15, wherein the foaming means has a plurality of foam nozzles that individually generate the microbubbles in the foam chamber.   The gas dissolution liquid production | generation apparatus of Claim 16 with which the inner wall face of the injection port of the said foaming nozzle has spread at the angle of 5 to 10 degree | times with respect to the injection direction.   18. The gas solution according to claim 15, wherein the foaming means is provided at a bottom portion of the foaming chamber, and jets the liquid toward an upper portion of the foaming chamber. Generator. The microbubble generator further includes
A liquid outlet provided on a side surface of the foaming chamber and discharging the liquid containing the microbubbles;
An excess gas outlet provided on the upper surface of the foaming chamber, for discharging excess gas generated from the liquid;
The gas solution generator according to any one of claims 15 to 18, characterized by comprising: In the gas-liquid mixing part, gas and liquid are mixed,
In the microbubble generating unit into which the liquid containing the gas flows, the gas contained in the liquid is converted into microbubbles,
In the nanobubble generator into which the gas containing the microbubbles flows, the microbubbles contained in the liquid are converted into nanobubbles,
Circulating the liquid containing the nanobubbles through the gas-liquid mixing unit, the microbubble generating unit, and the nanobubble generating unit, and increasing the gas dissolution concentration in the liquid,
A method for producing a gas solution characterized by the above.

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