JP2011088076A - Method and apparatus for generating gas-liquid mixed liquid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for generating a gas-liquid mixed liquid in which gas is present in liquid with a high density in the form of stable nano-size bubbles for a long period of time. <P>SOLUTION: A gas is supplied into a liquid, and while the liquid into which the gas has been supplied is pressurized at a pressurization rate of 0.17 MPa/sec or more, the liquid and the gas are mixed. When mixing them, the pressure of the liquid is adjusted to 0.15 MPa or more to generate a gas-liquid mixed liquid in a pressurized state. While maintaining the pressurized state, the generated gas-liquid mixed liquid is stored in a liquid storage tank 5 in a predetermined amount in an airtight state. Subsequently, the pressure of the gas-liquid mixed liquid stored in the liquid storage tank is reduced to atmospheric pressure at a depressurization rate of 2,000 MPa/sec or less, whereby a gas-liquid mixed liquid where nano-size bubbles are mixed in the liquid can be generated. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for producing a gas-liquid mixed solution and a gas-liquid mixed solution producing apparatus in which nano-sized bubbles are stably present in a liquid.

  Conventionally, a gas-liquid mixed liquid in which fine bubbles are dispersed in a liquid is known. In particular, nanobubble water in which nano-order size bubbles are mixed with water has extremely small bubble size compared to normal bubbles, and therefore has unique properties, and has been tried to be used in various fields. (For example, refer to Patent Document 1).

  However, the fine bubbles in the liquid tend to disappear by dissolving or coalescing, and it has been difficult to stably exist in the liquid. For this reason, gas is continuously supplied to the liquid for bubbling, or a strong force is applied to agitate to generate bubbles, and the liquid is used so that the generated bubbles do not disappear. Yes. Further, as the size of the bubbles becomes nano-order and the size of the bubbles becomes finer, the bubbles are more difficult to be generated and more easily disappeared, and it is more difficult to use the liquid in which the bubbles are dispersed.

  Patent Documents 2 to 4 disclose that nanobubbles are stabilized by rapidly reducing microbubbles. In the methods of these literatures, a part of the microbubbles is reduced by applying a force of strength, and both ions having opposite signs attracted to the aqueous solution near the interface by ions adsorbed on the gas-liquid interface and electrostatic attractive force. The ions are concentrated in a minute volume at a high concentration to act as a shell surrounding the microbubbles, and the nanobubbles are stabilized by inhibiting the diffusion of the gas in the microbubbles into the aqueous solution. However, in order to stabilize nanobubbles, it is necessary to generate an electrostatic force at the gas-liquid interface, so the presence of an electrolyte is indispensable. In solutions such as pure water where electrolytes are not dissolved, It could not exist stably.

  In addition, since only a part of the microbubbles is reduced, there is a problem that the amount of nanobubbles is small and it is difficult to obtain the effect. Furthermore, since the nanobubbles are stabilized by ions surrounding the bubble, it is not easy to control the stable state of the bubble by dissolving or coalescing the bubble, and the use of a gas-liquid mixture is not possible. It was limited.

  Patent Document 5 discloses that nanobubbles are generated by electrolyzing water and then applying ultrasonic waves. However, in the electrolysis of water, the gas is limited to hydrogen and oxygen, the amount of gas generated by electrolysis is small, and the generated bubbles are not stabilized. And the bubbles could not be stably maintained over a long period of time.

JP 2008-156320 A JP 2005-245817 A JP 2005-246293 A JP 2005-246294 A JP 2003-334548 A

  The present invention has been made in view of the above points, and a method for producing a gas-liquid mixed liquid in which a gas is present in a liquid as a high-density and stable nano-sized bubble over a long period of time, and gas-liquid An object of the present invention is to provide a mixed liquid generating apparatus.

  According to the first aspect of the present invention, a gas is supplied to the liquid, the liquid and the gas are mixed while pressurizing the liquid supplied with the gas at a pressurization speed of 0.17 MPa / sec or more, and the pressure of the liquid is set to 0.15 MPa. By doing so, nano-sized bubbles are formed to generate a gas-liquid mixture in a pressurized state, and the generated gas-liquid mixture is stored in a liquid storage tank 5 in a sealed state while maintaining the pressurized state. The gas-liquid mixed liquid in which nano-sized bubbles are mixed with the liquid by reducing the pressure of the gas-liquid mixed liquid stored in the liquid storage tank 5 to atmospheric pressure at a pressure reduction speed of 2000 MPa / sec or less. Is a method for producing a gas-liquid mixed liquid.

  The invention of claim 2 is a method for producing a gas-liquid mixture, wherein the liquid is pressurized and mixed by the pump 11 in the method for producing a gas-liquid mixture.

  According to a third aspect of the present invention, there is provided the gas-liquid mixed liquid production method, wherein the pump 11 pressurizes and mixes the liquid using the rotating body 21 while shearing the liquid. It is a generation method.

  A fourth aspect of the invention is a method for producing a gas-liquid mixture, wherein the liquid is pressurized and mixed by the venturi tube 12 in the method for producing the gas-liquid mixture.

  The invention of claim 5 includes a gas supply unit 2 for supplying a gas to the liquid, and the liquid and the gas are mixed while pressurizing the liquid supplied with the gas at a pressure rate of 0.17 MPa / sec or more. A pressure mixing unit 1 that generates a gas-liquid mixture in a pressurized state by setting the pressure to 0.15 MPa or more, and a liquid storage tank that stores the gas-liquid mixture generated in the pressure mixing unit 1 in a sealed state 5, a pressure holding unit 3 that maintains the pressurized state of the gas-liquid mixture, and a pressure adjustment unit 4 that adjusts the pressure of the gas-liquid mixture stored in the liquid storage tank 5. Is a pressure-adjusted pressure of a predetermined amount of the gas-liquid mixed liquid stored in the liquid storage tank 5 so that the pressure is reduced to atmospheric pressure at a pressure reduction speed of 2000 MPa / sec or less. Device.

  According to a sixth aspect of the present invention, in the gas-liquid mixed liquid generating apparatus described above, the pressure holding unit 3 is provided in the flow path 6 for sending out the liquid at the front stage or the rear stage of the pressure mixing unit 1, The gas-liquid mixed liquid generating apparatus is characterized in that when it is generated and the driving of the pressure mixing unit 1 is stopped, the pressurized state of the gas-liquid mixed liquid is maintained.

  According to a seventh aspect of the present invention, in the gas-liquid mixed liquid generating apparatus, the pressure adjusting unit 4 sets the pressure of the pressurized gas-liquid mixed liquid stored in the liquid storage tank 5 to at least the pressure mixing unit 1. Is a gas-liquid mixed liquid generating apparatus characterized in that it is kept constant during the driving.

  According to the invention of claim 1, by rapidly pressurizing and mixing the liquid into which the gas has been injected, bubbles having a strong interface structure are generated and stably exist even when the pressure is returned to atmospheric pressure. Size bubbles can be generated, and by gradually reducing the gas-liquid mixture having bubbles with a strong interface structure to atmospheric pressure, the bubbles can be extinguished while maintaining a strong interface structure. A gas-liquid mixed liquid in which nano-sized bubbles are mixed can be stably obtained without combining them, and the gas-liquid mixed liquid can be generated efficiently and easily. It is possible to depressurize a large amount of gas-liquid mixture at a time by reducing the pressure in the liquid storage tank, and when the generated gas-liquid mixture is stored in the liquid storage tank when necessary. It can be taken out and used, and a gas-liquid mixture can be easily generated and used in large quantities. Further, if the pressure is reduced in the liquid storage tank, the pressure can be reduced without clogging the piping, and the gas-liquid mixture can be generated stably.

  According to the second aspect of the present invention, since the liquid can be rapidly pressurized and mixed by the pump, a gas-liquid mixed solution having a strong bubble interface structure can be reliably generated.

  According to the third aspect of the present invention, the structure of the bubble interface is strong because it is possible to form a nano-sized bubble by shearing and mixing the gas injected into the liquid while being pressurized with a strong force by the rotating body. A gas-liquid mixture can be generated more reliably.

  According to the invention of claim 4, since the liquid can be rapidly pressurized and mixed by the venturi tube, a gas-liquid mixed solution having a strong bubble interface structure can be reliably generated.

  According to the invention of claim 5, by rapidly pressurizing and mixing the liquid into which the gas has been injected, the bubbles having a strong interface structure are generated and stably exist even when the pressure is returned to atmospheric pressure. Size bubbles can be generated, and by gradually reducing the gas-liquid mixture having bubbles with a strong interface structure to atmospheric pressure, the bubbles can be extinguished while maintaining a strong interface structure. A gas-liquid mixed liquid in which nano-sized bubbles are mixed can be stably obtained without combining them, and the gas-liquid mixed liquid can be generated efficiently and easily. It is possible to depressurize a large amount of gas-liquid mixture at a time by reducing the pressure in the liquid storage tank, and when the generated gas-liquid mixture is stored in the liquid storage tank when necessary. It can be taken out and used, and a gas-liquid mixture can be easily generated and used in large quantities. Further, if the pressure is reduced in the liquid storage tank, the pressure can be reduced without clogging the piping, and the gas-liquid mixture can be generated stably.

  According to the invention of claim 6, since the pressurized state of the gas-liquid mixture is maintained even when the pressurizing and mixing unit is stopped, the pressurized gas-liquid mixture is rapidly depressurized to form nano-sized bubbles. The gas-liquid mixture can be generated while maintaining the nano-sized bubbles in a stable state.

  According to the seventh aspect of the invention, while the pressure mixing unit is driven, unnecessary pressure is applied to the gas-liquid mixed liquid by keeping the pressure state of the gas-liquid mixed liquid constant. The size of bubbles can be prevented from collapsing, and since the pressure is kept constant, the amount of nano-sized bubbles generated in the pressure mixing section can be stabilized. A gas-liquid mixture with a stable amount can be produced.

It is the schematic which shows an example of embodiment of a gas-liquid liquid mixture production | generation apparatus. It is the schematic which shows a part same as the above. It is the schematic which shows a part same as the above. It is the schematic which shows a part same as the above. It is the schematic which shows another example of embodiment of a gas-liquid mixed-liquid production | generation apparatus. It is the schematic which shows another example of embodiment of a gas-liquid mixed-liquid production | generation apparatus. It is a conceptual explanatory drawing of the gas-liquid interface of the bubble in a gas-liquid mixed liquid. An example of specific embodiment of a gas-liquid mixed-liquid production | generation apparatus is shown, (a) is a top view, (b) is a front view. It is a graph which shows the difference of the infrared absorption spectrum of the gas-liquid mixed liquid using nitrogen and water, and nitrogen saturated water. It is a graph which shows the gas volume contained in a gas-liquid liquid mixture. It is a photograph of the gas-liquid mixed solution by a scanning electron microscope (SEM). It is a graph which shows stability of a gas-liquid liquid mixture.

  Hereinafter, modes for carrying out the invention will be described.

In the method for producing a gas-liquid mixture of the present invention, gas is supplied to the liquid, and the liquid supplied with the gas is pressurized at a pressure rate ΔP ₁ / t (ΔP ₁ : pressure increase amount of 0.17 MPa / sec or more). , T: time), the liquid and the gas are mixed while being pressurized. At that time, the pressure of the liquid is set to 0.15 MPa or more by pressurization. As a result, nano-sized bubbles are formed, and a pressurized gas-liquid mixture is generated. Then, a predetermined amount of the generated gas-liquid mixed liquid is stored in the liquid storage tank 5 in a sealed state while maintaining the pressurized state, and then the pressure of the gas-liquid mixed liquid stored in the liquid storage tank is set to 2000 MPa / The pressure is reduced to atmospheric pressure at a pressure reduction rate ΔP ₂ / t (ΔP ₂ : amount of pressure reduction, t: time) of less than or equal to sec. As a result, the gas-liquid mixture is gradually depressurized to atmospheric pressure, and the gas-liquid mixture can be generated while maintaining the nano-sized bubbles. The gas-liquid mixed liquid refers to a liquid in which nano-sized bubbles are mixed in the liquid with a substantially uniform distribution density.

  The bubbles contained in the gas-liquid mixture are nano-sized bubbles, specifically, bubbles of 1000 nm or less (so-called nano bubbles). When the bubbles are nano-sized and fine, a strong bubble interface structure can be formed, and a high-concentration gas can be held in the liquid. Further, since buoyancy does not act on the nano-order size bubbles, the bubbles do not rise and separate from the liquid, so that the bubbles can exist stably over a long period of time. If the bubble size is larger than the nano size, the bubble may not be stabilized. In addition, the bubble size can be measured by a scanning electron microscope (SEM), and the average particle diameter of the bubbles can be obtained by averaging the particle diameters of the bubbles obtained by the measurement. By the way, the liquid mixed with microbubbles is cloudy and can be discriminated visually. However, the liquid mixed with nanobubbles is colorless and transparent (or the color of the liquid when the liquid is colored) and can be discriminated visually. Can not. Therefore, the determination of the gas-liquid mixture is performed by SEM, density measurement, or the like. The lower limit of nano-sized bubbles is 1 nm.

  As the liquid used for the production of the gas-liquid mixture, it is preferable to use a liquid composed of molecules that form hydrogen bonds. A hydrogen bond is a bond that stabilizes the system in a molecule that has a high electronegativity atom and a hydrogen atom, because the hydrogen atom approaches the high electronegativity atom of another molecule. . Bubbles are present in the liquid forming the gas-liquid mixture, and in the liquid molecules existing around the bubbles, that is, at the interface with the bubbles, the distance of hydrogen bonding between the molecules is The distance is shorter than the hydrogen bond distance at (25 ° C., 1 atm (0.1013 MPa)). In this way, when the gas-liquid mixture exists under normal temperature and normal pressure conditions, the hydrogen bond distance at the bubble interface becomes shorter than the normal hydrogen bond distance at normal temperature and normal pressure, thereby It will be surrounded by liquid molecules that form strong hydrogen bonds. And the liquid molecule which formed this hydrogen bond turns into a firm shell, and encloses a bubble. As a result, even if the bubbles collide with each other, they will not collapse, and the pressure from the liquid can be countered by the stress from the inside of the bubbles, so the bubbles can be held without disappearing or coalescing in the liquid. Is something that can be done. In other words, it is different from conventional bubbles that are stable with surface tension. Thus, particularly when a liquid composed of molecules that form hydrogen bonds is used as the liquid, the distance between the hydrogen bonds of the molecules present at the interface with the bubbles of the liquid is determined when the liquid is at normal temperature and pressure. Since the distance can be shorter than the distance between hydrogen bonds, nano-sized bubbles can be more stably present.

  One of the liquids preferably used for the gas-liquid mixture is water. The water molecule is a hydrogen bond of O ... H, that is, a hydrogen bond is formed between an oxygen atom of one water molecule and a hydrogen atom of another water molecule, and water is used as the liquid of the gas-liquid mixture. Then, this hydrogen bond in the liquid becomes stronger at the bubble interface, and the bubbles can be further stabilized. In addition, water can be obtained stably with abundant supply sources, and furthermore, water in which bubbles are dispersed has a wide range of applications, so that a highly useful gas-liquid mixture can be obtained. That is, in the present invention, the water is not limited to high-purity water, and any water can be used including water and sewage systems, ponds, seawater, and the like. That is, any material that contains water as a liquid may be used.

Further, the liquid is a liquid composed of molecules having any one or more of (halogen) -H bond and S—H bond such as O—H bond, N—H bond, F—H bond and Cl—H bond. It is also preferable. These bonds are bonds between atoms and hydrogen atoms having a sufficiently large electronegativity with respect to hydrogen atoms, such as OH ... O, NH ... N, FH ... F, and Cl-H ... Cl. (Halogen) -H (Halogen), S—H,... S, and so on, are formed, and by this hydrogen bond, bubbles can be surrounded and stabilized. A typical liquid having an O—H bond is water, but other examples include hydrogen peroxide, alcohols such as methanol and ethanol, and glycerin. Moreover, ammonia etc. can be illustrated as a liquid which has a N-H bond. Examples of those having a (halogen) -H bond include HF (hydrogen fluoride) having an F-H bond and HCl (hydrogen chloride) having a Cl-H bond. Examples of those having an S—H bond include H ₂ S (hydrogen sulfide).

  It is also preferable that the liquid is a liquid composed of molecules having a carboxyl group. The carboxyl group has a carbonyl oxygen atom with high electronegativity, and the carbonyl oxygen atom in one carboxyl group and a hydrogen atom in another carboxyl group form a strong hydrogen bond to surround the bubble. Therefore, it is possible to obtain a gas-liquid mixture in which bubbles are stably present. Examples of the liquid composed of molecules having a carboxyl group include carboxylic acids such as formic acid and acetic acid.

  The gas used for the gas-liquid mixture is not particularly limited, and various gases can be used. For example, gases such as air, carbon dioxide, nitrogen, oxygen, ozone, argon, hydrogen, helium, methane, propane, and butane can be used singly or in combination.

  The amount of gas injected into the liquid is preferably such an amount that the concentration of the gas contained in the gas-liquid mixed liquid is equal to or higher than the saturated dissolution concentration of the liquid when it is generated. If a saturated gas amount or a large amount of gas exceeding it is held in the liquid, a high-concentration gas contained in the liquid can be used, and the utility value of the gas-liquid mixture can be increased. . More preferably, a saturated dissolved amount of gas is dissolved in the gas-liquid mixed liquid, and bubbles are present in the saturated dissolved liquid. If the gas is dissolved in the saturated dissolution amount, it becomes possible to stabilize the gas in the form of bubbles without dissolving them and to hold them in the liquid as bubbles. In other words, a gas-liquid mixed solution in which a gas is present in excess of the saturated dissolution amount has a gas dissolved at a saturated concentration in the liquid, and the bubbles do not collapse or dissolve, and the bubbles are more stably contained in the liquid. Can be present. Furthermore, it is preferable that the dissolved concentration of the gas is a saturated dissolved concentration. When the gas concentration is increased in this way, the bubbles can be stabilized in a state where the hydrogen bond distance is shortened, and the action of various activities (physiological activity, detergency, etc.) becomes stronger, and the utility value is increased. Can be further increased. The amount of gas in the gas-liquid mixture can be calculated from the amount of mass change by separating the gas from the gas-liquid mixture as shown in the examples described later.

  In the generation of the gas-liquid mixture, it is preferable that the gas pressure forming the bubbles, that is, the internal pressure of the bubbles is 0.12 MPa or more, and the Young Laplace equation (the following equation) It is preferable that the pressure be higher than the internal pressure of the bubbles given by

Young Laplace's formula ΔP = 2σ / r
[ΔP: rising pressure inside the bubble, σ: surface tension, r: bubble radius]

When the internal pressure of the bubbles becomes such a pressure, the bubbles are maintained at a high internal pressure, and a stronger interface structure can be formed. Therefore, stable bubbles can be formed in a stationary state. On the other hand, once an impact is applied to the gas-liquid mixture, the balance of the internal pressure force is disrupted, the liquid shell in which hydrogen bonds are formed collapses, the bubbles merge, foam and escape from the liquid Therefore, this foaming can be used. The internal pressure of the bubbles in the gas-liquid mixed liquid can be calculated by applying the total gas amount in the gas-liquid mixed liquid and the gas volume calculated from the density to the gas equation of state as shown in the examples described later.

  Further, the hydrogen bond distance of the liquid molecules at the interface with the bubble will be appropriate depending on the liquid used, but it will be 99% or less when the hydrogen bond distance at room temperature and normal pressure is 100%. It is preferable to produce a gas-liquid mixture. When the hydrogen bond distance falls within this range, the bubbles can be surrounded and stabilized by a hard shell of hydrogen bonds. If the distance between hydrogen bonds is longer than this, there is a possibility that bubbles cannot be stabilized and exist. Considering the interatomic distance, the lower limit of the hydrogen bond distance is 95%. The hydrogen bond distance at the bubble interface in the gas-liquid mixture can be calculated by analyzing the infrared absorption spectrum (IR) of the gas-liquid mixture as shown in the examples described later.

  By the way, water having a hydrogen bond distance of the above-mentioned distance usually has a solid or hydrate crystal structure like ice. However, in the gas-liquid mixture produced by the present invention, it is locally present at the bubble interface. In general, hydrogen bonds having a short distance as described above are formed, and normal hydrogen bonds are formed in other liquids. That is, a hard shell of liquid molecules is formed by hydrogen bonds at a short distance at the bubble interface to prevent the bubbles from coalescing and disappearing, and at other than the bubble interface, liquid exists in a normal state and normal temperature At normal pressure, fluidity is ensured, and it is easy to use liquid in which stable bubbles are present.

In addition, when water is used as the liquid, the gas-liquid mixture produced according to the present invention has a negative zeta potential, and the area of the bubble interface existing in a volume of 1 cm ³ is about 1.2 m ² . Such characteristics can be used in various fields.

  FIG. 1 is a schematic view showing an example of an embodiment of the gas-liquid mixed liquid generating apparatus of the present invention. With this apparatus, the gas-liquid mixed liquid as described above can be generated.

  This gas-liquid mixed liquid generating apparatus is an apparatus that generates a gas-liquid mixed liquid in a batch system, and includes a gas supply unit 2 that supplies a gas to a liquid sent from a liquid supply source, and a liquid supplied with the gas. A pressure mixing unit 1 that generates a pressurized gas-liquid mixture by mixing liquid and gas while applying pressure, and a liquid storage that stores the gas-liquid mixture generated in the pressure mixing unit 1 in a sealed state. A tank 5, a pressure holding unit 3 that maintains the pressurized state of the gas-liquid mixture, and a pressure adjustment unit 4 that adjusts the pressure of the gas-liquid mixture stored in the liquid storage tank 5. A flow path 6 through which liquid flows is connected to 5.

  The upstream side of the flow path 6 (the side opposite to the liquid storage tank 5) is connected to a liquid supply source such as a water pipe or a liquid storage tank, and the liquid supplied from this liquid supply source passes downstream through the flow path 6. To the side (liquid storage tank 5 side). As the pressure for sending the liquid to the flow path 6, the pressure of the pressurized liquid supply source such as a water pipe may be used, or the pumping pressure of the pump 11 described later may be used.

  The gas supply unit 2 is connected to the flow path 6 to supply and inject a gas to the liquid sent from the liquid supply source. For example, in the case of injecting air as a gas, the gas supply unit 2 can be formed by connecting the other end of the tube whose one end is opened to the atmosphere to the flow path 6. The gas can be supplied to the liquid by the negative pressure at the time. Or when supplying oxygen, ozone, hydrogen, nitrogen, a carbon dioxide, argon etc. as gas, the gas supply part 2 can be formed by connecting the cylinder etc. which enclosed these gas to the flow path 6. FIG. Alternatively, when ozone is used as the gas, an ozone generator may be connected to the gas supply unit 2. The connection position of the gas supply unit 2 to the flow path 6 may be a position upstream of the pressure mixing unit 1, and is preferably a position upstream of the pressure holding unit 3 as in this device. .

  The pressurizing and mixing unit 1 is provided in the flow path 6 and mixes the liquid and the gas while pressurizing the liquid supplied with the gas by the gas supply unit 2 to make the gas into a fine nano-sized bubble and into the liquid. Dispersed and mixed to produce a pressurized gas-liquid mixture. In this apparatus, the pressure mixing unit 1 is formed by a pump 11. The pressurizing and mixing unit 1 can be configured by applying a stirring force by changing the cross-sectional area of the flow path or the like, and if the liquid is flowing through the flow path 6 with stirring, the flow path is simply However, when the gas 11 is pressurized and mixed with the pump 11, the liquid can be rapidly pressurized and mixed. It can be generated reliably. Moreover, when using the pump 11, the liquid of the atmospheric pressure stored in the liquid supply source can be pumped up.

  FIG. 2 is a schematic view of a main part showing an example of a specific form of the pump 11. The pump 11 a pressurizes the liquid by the rotation of the rotating body 21, and the rotating blades 22 attached to the rotating body 21 continuously rotate to pump the pump outlet 27 through the pump passage chamber 23 from the pump inlet 26. The liquid is sent out in the direction of flow to and pressurized. In the figure, the white arrow indicates the flow direction of the liquid, and the solid line arrow indicates the rotation direction of the rotating body 21. The pump 11a includes four rotary blades 22. Further, the rotating shaft 25 of the rotating body 21 is arranged so as to be deviated toward the pump outlet 27 side from the cylindrical center of the pump wall 24 formed in a cylindrical shape, and is provided as an eccentric shaft. The volume of the second flow path chamber 23b of the pump flow path chamber 23 is formed smaller than the volume of the first flow path chamber 23a due to the eccentricity of the rotary shaft 21, and the pump flow path chamber is arranged along the liquid flow direction. The volume of 23 is gradually reduced.

Then, the liquid fed to the pump flow passage chamber 23 is pressurized is fed by rotating blades 22, large bubbles B _B due to rapid pressure changes bubbles B _N of subdivided by fine nano-sized generated . That is, the liquid sent from the first flow path chamber 23a to the second flow path chamber 23b along with the rotation of the rotating body 21 is rapidly compressed and pressurized as the volume of the pump flow path chamber 23 becomes smaller. Nano-sized bubbles _BN are generated by the pressure. Further, in the illustrated pump 11a, a shearing force is applied when the liquid passes between the inner surface of the pump wall 24 and the tip of the rotor blade 22, and the liquid is pressurized while being sheared by the clearance. At this time, the gas (large bubbles B _B ) mixed in the liquid is sheared by the shearing force applied to the liquid and becomes finer nano-sized bubbles (B _N ). The distance narrowest part between the inner surface of the pump wall 24 and the tip portion of the rotor blades 22, i.e. the clearance distance L _C is preferably 5Myuemu～2mm. Thus, according to the pump 11a using the rotator 21, it is possible to form nano-sized bubbles by shearing the gas injected into the liquid while being rapidly pressurized with the rotator 21 with a strong force. A gas-liquid mixture having a strong bubble interface structure can be generated more reliably.

  The rotational speed of the rotating body 21 of the pump 11 is preferably 100 rpm or more. At this time, it becomes 1/2 rotation or more in 0.3 seconds. By having such a rotational speed, it is possible to reliably generate nano-sized bubbles in which the hydrogen bond distance is shortened by injecting a gas having a saturation dissolution concentration or more into the liquid.

  Here, as shown in FIG. 3, a venturi tube 12 is provided in the upstream flow path 6 of the pressure mixing unit 1, and the side tube of the venturi tube 12 functions as the gas supply unit 2 to supply gas to the liquid. At the same time, it is also preferable to pressurize and mix the liquid supplied with the gas by causing the main body of the venturi tube 12 to function as a part (or all) of the pressure mixing unit 1. In that case, the gas can be supplied to the liquid with a simple configuration and the liquid can be rapidly pressurized and mixed. In addition, when the liquid is pressurized by a plurality of pressurizing mechanisms such as the pump 11 and the venturi tube 12, the liquid is strongly pressurized, and a gas-liquid mixed liquid having a strong bubble interface structure can be reliably generated. In addition, you may comprise the pressurization mixing part 1 only with the venturi pipe | tube 12 without using the pump 11, In that case, an apparatus structure can be made simpler.

  The illustrated venturi tube 12 includes an inflow side tube portion 12a whose cross-sectional area gradually decreases from the inflow side to the outflow side, a throttle tube portion 12b having the smallest cross-sectional area in the venturi tube 12, and an outflow side from the inflow side. It consists of the outflow side pipe | tube part 12c from which a cross-sectional area becomes large gradually toward the side. One end of a side tube that functions as the gas supply unit 2 is connected to the throttle tube portion 12b, and the gas supplied from the side tube is injected into the liquid in the throttle tube portion 12b. In this example, the length (T2) of the outflow side pipe portion 12c is formed longer than the length (T1) of the inflow side tube portion 5a, thereby reducing the cross-sectional area at the inflow side pipe portion 12a. Then, the gas is mixed with the gas in the throttle tube portion 12b, and then sent out to the downstream side while being rapidly pressurized in the outflow side tube portion 12c, and the liquid and the gas are vigorously mixed.

  The liquid storage tank 5 is for storing the produced gas-liquid mixture. The liquid storage tank 5 is formed as an airtight tank so that the pressure of the gas-liquid mixed solution sent in a pressurized state can be maintained, and is configured by, for example, a pressure-resistant tank.

  A predetermined amount of the gas-liquid mixture is generated by starting and stopping the driving of the pump 11 which is the pressure mixing unit 1. That is, when the pump power source connected to the pump 11 is turned on, the driving of the pump 11 is started, and the liquid and the gas are mixed in the pressure mixing unit 1 under a high pressure condition. Thereby, a strong interface structure is formed around the bubbles, and the bubbles can be covered with the shell of the strong interface structure, and the gas can be stabilized as fine bubbles. The generated gas-liquid mixed solution is sequentially sent out to the liquid storage tank 5 through the flow path 6. Then, when the amount of the gas-liquid mixed liquid stored in the liquid storage tank 5 reaches a predetermined amount, the pump power supply is turned off to stop the driving of the pump 11 and the liquid delivery is stopped. When the pressure mixing unit 1 is not of a mechanism for controlling the power supply (for example, when only the venturi tube 12 is used), the driving of the pressure mixing unit 1 is automatically performed by starting or stopping the delivery of the liquid to the flow path 6. Started or stopped.

By the pressure mixing unit 1 as described above, a strong pressure is suddenly applied to the liquid into which the gas is injected, and the bubbles present in the liquid are subdivided into fine nano-sized bubbles and dispersed in the liquid. Is done. In addition, a strong interface structure is formed by liquid molecules at the interface of the bubbles that have become high pressure due to a sudden pressure change. At that time, when the pressurization rate ΔP ₁ / t (ΔP ₁ : pressure increase, t: time) is 0.17 MPa / sec or more, the bubbles are subdivided to generate fine nano-sized bubbles. The pressure of the gas-liquid mixture when it is sent from the pressure mixing unit 1 to the liquid storage tank 5 is 0.15 MPa or more, thereby generating nano-sized bubbles with a strong structure at the bubble interface. Is something that can be done. In consideration of substantial pressurization conditions, the upper limit of the pressurization rate ΔP ₁ / t is 167 MPa / sec, and the upper limit of the pressure of the pressurized gas-liquid mixture is 50 MPa.

  The generated gas-liquid mixed solution is sent out to the liquid storage tank 5, and at that time, the gas-liquid mixed solution may be rapidly depressurized as it flows out to the liquid storage tank 5. If the pressurized gas-liquid mixture is rapidly depressurized, the nano-sized bubbles may collapse and the gas may be separated. Therefore, in the gas-liquid mixed liquid generating apparatus described above, the pressure holding unit 3 is maintained so as to maintain the pressurized state of the gas-liquid mixed liquid sent out from the pressure mixing unit 1 and stored in the liquid storage tank 5. Is provided in the flow path 6.

  In the above-described apparatus, the pressure holding unit 3 is provided in the flow path 6 on the upstream side (previous stage) with respect to the pressure mixing unit 1. However, the pressure holding unit 3 is not limited to this, and the pressure holding unit 3 is stored with the pressure mixing unit 1. You may make it provide in the flow path 6 between the liquid tanks 5, ie, the flow path 6 of the back | latter stage of the pressurization mixing part 1. FIG. By providing the pressure holding unit 3 in this manner, the gas-liquid mixed liquid is sent out while being maintained in a pressurized state and stored in the liquid storage tank 5, so that nano-sized bubbles can be prevented from collapsing. .

  The pressure holding unit 3 preferably maintains the pressurized state of the gas-liquid mixed solution when a predetermined amount of the gas-liquid mixed solution is generated and the driving of the pressure mixing unit 1 is stopped. That is, when the driving of the pressure mixing unit 1 such as the pump 11 is stopped, the pressure for sending out the liquid may disappear, the gas-liquid mixture may flow backward to the upstream side, and the gas-liquid mixture may be rapidly reduced. If the gas-liquid mixture is rapidly depressurized, the nano-sized bubbles may collapse and the gas may be separated. Therefore, even after the driving of the pump 11 is stopped, the pressure holding unit 3 maintains the pressurized state of the gas-liquid mixed solution and prevents the pressure from being rapidly reduced.

  As the pressure holding unit 3, for example, an electric opening / closing means for electrically controlling the opening / closing of the valve can be provided. In the apparatus of FIG. ing. According to the electric valve 31, the opening and closing of the valve can be reliably controlled by electric control, so that the pressurized state of the gas-liquid mixture can be reliably maintained, and the gas-liquid mixture can be depressurized inadvertently by backflow. It is possible to prevent nano-sized bubbles from collapsing.

  In addition, the pressure holding unit 3 can be configured by the backflow prevention valve 32. In the embodiment of the gas-liquid mixed liquid generating apparatus of FIG. 5, the pressure holding unit 3 is configured by a backflow prevention valve 32. Thus, if the pressure holding unit 3 is configured by the backflow prevention valve 32, the gas-liquid mixture can be prevented from flowing back and depressurizing with a simple configuration, and the pressure state of the gas-liquid mixture can be easily changed. It can maintain and prevent collapse of nano-sized bubbles. In the apparatus of FIG. 5, the apparatus configuration other than the pressure holding unit 3 is the same as that of the apparatus of FIG.

  Thus, the gas-liquid mixed liquid generated by the start and stop of the driving of the pressure mixing unit 1 is stored in the liquid storage tank 5 in a predetermined amount. Then, the liquid storage tank 5 is depressurized to the atmospheric pressure in order to take out the gas-liquid mixture to the outside and use it.

The pressure adjusting unit 4 adjusts the pressure of the gas-liquid mixed liquid stored in the liquid storage tank 5, and gradually increases the pressure of the pressurized gas-liquid mixed liquid without generating large bubbles. The pressure is reduced to atmospheric pressure. When the gas-liquid mixture produced by pressurization and mixing as described above is in a high-pressure state and is discharged to the outside as it is under atmospheric pressure, bubbles in the gas-liquid mixture are caused by a sudden pressure drop. There is a possibility that the gas may coalesce and be discharged from the liquid, and cavitation may occur. Therefore, when the pressure adjustment unit 4 is provided to reduce the pressurized gas-liquid mixture to atmospheric pressure, the pressure adjustment unit 4 gradually reduces the pressure to atmospheric pressure while adjusting the pressure, and discharges it to the outside. It is something that is made possible. The pressure adjusting unit 4 is provided on the upper side of the liquid storage tank 5 and has a pressure reducing rate ΔP ₂ / t (ΔP2: pressure reducing amount, t: The upper limit of (time) is 2000 MPa / sec or less, and the gas-liquid mixed liquid is decompressed. Thus, the gas-liquid mixture can be taken out without erasing or coalescing the nano-sized bubbles while maintaining the structure of the strong bubble interface.

When the gas is released by the pressure reducing on / off valve 33, a narrow tube (slow pressure reducing tube) having a diameter of about 0.1 to 1 mm and a length of about 1 mm or more (preferably 5 mm or more) is connected to the pressure reducing on / off valve 33. It is preferable to release gas from The pressure can be gradually reduced gradually by releasing the gas through the narrow tube. That is, the slow pressure reducing pipe 14 (see FIG. 8 to be described later) is for reducing the pressure of the liquid storage tank 5 by ΔP ₂ / t. It is. Since the compressed gas is extracted, a gentle pressure reduction can be achieved. If the liquid is removed, a sudden decompression occurs even if a small amount of liquid is removed, which may cause a problem that the nano-sized bubbles collapse. Therefore, it is preferable to remove the gas from the liquid.

  As described above, in the gas-liquid mixed liquid generating apparatus described above, it is possible to depressurize a large amount of the gas-liquid mixed liquid at a time by reducing the pressure in the liquid storage tank 5, and storing the generated gas-liquid mixed liquid. It is possible to store liquid in the liquid tank 5 at atmospheric pressure (or at a pressure close to atmospheric pressure or in a pressurized state) and take it out to use when necessary. Can be easily generated and used in large quantities. Further, since the pressure is reduced in the liquid storage tank 5 that forms a sealed state, the sealed state can be maintained even after the pressure is reduced, and the gas-liquid mixture can be stably stored. That is, when a gas-liquid mixture is generated by reducing pressure while feeding liquid continuously, the nano-sized bubbles collapse due to the impact when the gas-liquid mixture is put into the storage tank, or the storage tank opens. The gas may be easily separated, and the gas may not be stably retained in the liquid for a long time. Further, if the storage tank is to be sealed by adjusting the pressure, there is a risk that the impact of the pressure change is applied to the gas-liquid mixture and the bubbles collapse. However, when the batch-type production is performed as in the above gas-liquid mixture production apparatus, the liquid storage tank 5 can be used as a storage tank as it is, and a larger amount of gas-liquid mixture can be used than in the continuous type. The nano-sized bubbles can be stably stored for a long time without collapsing. Further, when the pressure of the gas-liquid mixed liquid is reduced with a thin channel pipe or the like, there is a risk that the channel pipe will be clogged with dust or the like, resulting in a failure. It is possible to stably generate a gas-liquid mixed solution without such a situation.

  It is preferable that the pressure adjusting unit 4 further maintains the pressure of the pressurized gas-liquid mixture stored in the liquid storage tank 5 at least while the pressure mixing unit is driven. Since the gas-liquid mixed solution generated in the pressure mixing unit 1 is generated and then sequentially sent to the liquid storage tank 5, the liquid storage liquid 5 stores the liquid-liquid mixture in a pressurized state while gradually increasing the amount. Is done. On the other hand, the liquid storage tank 5 is hermetically sealed, and the pressure in the tank gradually increases as the pressurized gas-liquid mixture increases. If the pressure of the gas-liquid mixture increases too much, nano-sized bubbles may collapse due to the impact of pressure change. In addition, when a pressure higher than the pressure in the pressure mixing unit 1 is applied non-uniformly, there is a risk of destabilizing the nano-sized bubbles by changing the bubble diameter. Further, the pressure increase in the liquid storage tank 5 is transmitted and the pressure applied by the pressure mixing unit 1 is increased, and the amount of nano-sized bubbles generated in the pressure mixing unit 1 may change. However, during the driving of the pressure mixing unit 1 by the pressure adjusting unit 4, unnecessary pressure is applied to the gas-liquid mixture by making the pressure state of the gas-liquid mixture stored in the liquid storage tank 5 constant. The nano-sized bubbles can be prevented from collapsing, and the amount of nano-sized bubbles generated can be stabilized, and a gas-liquid mixture with a stable amount of nano-sized bubbles can be obtained. It can be generated.

  In order to maintain the pressure of the gas-liquid mixed liquid constant by the pressure adjusting unit 4, it can be performed by opening and closing the gas discharge valve 34 provided in the upper part of the liquid storage tank 5. In the above-described apparatus, a form in which the pressure reducing on / off valve 33 and the gas discharge valve 34 are used together is shown. However, a gas discharge valve 34 is provided separately from the pressure reducing on / off valve 33 and the upper part of the liquid storage tank 5 is provided. The gas stored in the liquid storage tank 5 may be discharged and adjusted so that the pressure in the liquid storage tank 5 is constant. When the gas discharge valve 34 is provided separately, it becomes easy to adjust the pressure at the time of storing and depressurizing the gas-liquid mixture under appropriate conditions by each valve, and easily maintain and depressurize the pressure. It is something that can be done.

  When generating the gas-liquid mixture, it is preferable to remove bubbles exceeding the nano size, that is, bubbles exceeding 1 μm in diameter, from the pressurized gas-liquid mixture stored in the storage tank 5. . In the liquid in which nano-sized bubbles are formed as described above, a gas of micro size or larger is also mixed and present. However, micro-sized bubbles or larger cannot stably exist in the liquid, and if they are present in the liquid, the nano-sized bubbles are merged or collapsed, and the nano-sized bubbles are not allowed. It will be stable. Therefore, the micro-sized or larger bubbles are removed from the gas-liquid mixture so that the bubbles are only nano-sized to stabilize the nano-sized bubbles.

  The removal of the micro-sized bubbles can be performed by removing the bubbles by raising them with their own buoyancy. Bubbles having a diameter exceeding 1 μm in diameter (micro-sized bubbles) are raised by buoyancy, and micro-sized bubbles are removed using this buoyancy. Bubbles removed and discharged from the liquid become gas and accumulate at the top of the tank. The gas thus released can be discharged by a pipe or the like for discharging the gas, and can be removed by, for example, the gas discharge valve 34 described above. By removing such relatively large bubbles and having nano-sized bubbles, which are fine bubbles, in the liquid, a stable gas-liquid mixture having a strong interface structure can be obtained.

  FIG. 4 is a schematic diagram showing how the micro-sized bubbles B are removed from the liquid storage tank 5. For convenience of explanation, the bubble B is enlarged and depicted. Buoyancy acts on the bubbles B in the liquid Lq stored in the liquid storage tank 5, and the bubbles B rise to the liquid level. The bubbles B that have reached the liquid level are released out of the liquid and stay in the upper part of the tank together with the gas in the upper part of the tank. The gas thus retained is discharged from the gas discharge valve 34.

  It is preferable that the depth D of the liquid storage tank 5, that is, the distance from the bottom surface of the liquid storage tank 5 to the upper surface of the gas-liquid mixed solution when a predetermined amount of the gas-liquid mixed solution is stored is 10 to 900 mm. Considering the following bubble rising speed, the depth of the liquid storage tank 5 falls within this range, so that the liquid storage amount can be sufficient and micro-sized bubbles can be easily removed by buoyancy. When the depth of the pressure holding container 30 is within this range, the amount of storage can be sufficient, and micro-sized bubbles can be easily removed by buoyancy.

From the Stokes law, the bubble rising speed V is
V (m / s) = 1/18 × g × d / γ
[G (m / s ² ): Gravitational acceleration, d (m): Bubble diameter, γ (m ² / s): Water kinematic viscosity coefficient]
It is.

  In addition, it is preferable to store the gas-liquid mixed liquid while maintaining the pressurized state (0.15 MPa or more) in the liquid storage tank 5 for about 0.1 to 1.0 seconds or longer. By holding and storing the gas-liquid mixture in the storage tank 5 for a predetermined time under a stationary condition, the micro-sized bubbles can be reliably removed by buoyancy. The capacity of the liquid storage tank 5 can be about 0.5 to 10 L.

  By the way, when applied to the Stokes equation, the bubble rising velocity V is V = 0.243 mm / sec when the bubble diameter is 20 μm, V = 0.06 mm / sec when the bubble diameter is 10 μm, and the bubble diameter is 1 μm. In this case, V = 0.006 mm / sec.

  For example, in the case of a cylindrical tank with an inner diameter of 100 mm, in order to completely separate 20 μm bubbles from water, from the bubble rising speed, the bubbles will rise and move 0.243 × 600 = 145 mm when left for 10 minutes (600 seconds). If the distance from the tank bottom to the water surface is 145 mm or less, 20 μm bubbles can be separated. In this case, the tank capacity is about 1L.

  When the same calculation is performed for the separation of 1 μm bubbles, the bubbles rise by 0.06 × 600 = 0.36 mm after 10 minutes and 2.16 mm after 1 hour and 51 mm after 24 hours.

  Therefore, the depth D of the pressure holding container 30 is set so that bubbles (bubbles of 1 μm or more) exceeding the nano size satisfy D (depth) <V (bubble rising speed) × T (stationary time). By setting or setting the time T for allowing the gas-liquid mixture to stand still in the pressure holding container 30 so that T (standing time)> D (depth) / V (bubble rising speed) It can be removed.

  The gas-liquid mixed liquid reduced to the atmospheric pressure is provided in the lower part of the liquid storage tank 5 and taken out to the outside by a liquid take-out part 7 constituted by a take-out valve 7a and a take-out flow path 7b. The take-off valve 7a is closed when the liquid storage tank 5 is sealed and stored, and is opened when the gas-liquid mixture is taken out. The gas-liquid mixture is taken out from the discharge port through the take-out flow path 7b.

In the gas-liquid mixed-liquid production | generation apparatus comprised as mentioned above, gas is supplied and inject | poured into the liquid sent from the liquid supply source by the gas supply part 2. FIG. Then, the liquid into which the gas has been injected is pressurized by the pressure mixing unit 1 at a pressure rate ΔP ₁ / t (ΔP ₁ : pressure increase amount, t: time) of 0.17 MPa / sec or more, and the pressure of the liquid is increased. Set to 0.15 MPa or more. That is, the pressure of the liquid when being sent out from the pressurizing and mixing unit 1 to the liquid storage tank 5 is 0.15 MPa or more. Thereafter, after the bubbles exceeding the nano size in the gas-liquid mixed liquid are removed in the liquid storage tank 5, the pressure is reduced by the pressure adjustment unit 4 to adjust the pressure reduction rate ΔP ₂ / t ( The pressure is gradually reduced to atmospheric pressure at ΔP ₂ : reduced pressure amount, t: time). As a result, a gas-liquid mixed liquid in which nano-sized bubbles are stably present can be generated.

  FIG. 6 is a schematic view showing another example of the embodiment of the gas-liquid mixed liquid generating apparatus. In addition to the apparatus shown in FIG. 1, this gas-liquid mixed liquid generating apparatus is provided with a liquid discharge part 8 as a pressure adjusting part 4 below the liquid storage tank 5. Further, the pressure holding unit 3 is provided at the subsequent stage of the pressure mixing unit 1. Other configurations are the same as those of the apparatus shown in FIG.

The liquid discharge unit 8 includes a discharge valve 8a that adjusts the pressure in the liquid storage tank 5 by discharging a part (or all) of the gas-liquid mixture to the outside by opening and closing, and the gas-liquid mixture used for pressure adjustment. And a discharge channel 8b for discharging the gas to the outside. In this apparatus, as in the apparatus of FIG. 1, a pressurized gas / liquid mixture is generated and stored in the liquid storage tank 5, and then the liquid / liquid mixture is gradually removed by the liquid discharge unit 8. The pressure in the liquid storage tank 5 is adjusted while discharging, and the pressure of the gas-liquid mixed liquid is reduced to the atmospheric pressure at a pressure reduction rate ΔP ₂ / t (ΔP ₂ : amount of pressure reduction, t: time) with a maximum pressure reduction rate of 2000 MPa / sec or less. Depressurize until. According to this apparatus, since the pressure can be reduced by discharging the gas-liquid mixture, the pressure in the tank can be reduced without causing the gas in the upper part of the tank to suddenly diverge and the pressure of the gas-liquid mixture to rapidly decrease. It can be gradually lowered and can prevent the collapse of nano-sized bubbles. The decompressed gas-liquid mixture can be taken out from the liquid take-out part 7.

  The pressure adjusting unit 4 is configured by the liquid discharge valve 8 and the pressure reducing on / off valve 33 by causing the gas exhaust valve 34 to function as the pressure reducing on / off valve 33 or providing the pressure reducing on / off valve 33 separately from the gas exhaust valve 34. Thus, the pressure can be adjusted when the gas-liquid mixture is depressurized. Moreover, the liquid extraction part 7 and the liquid discharge part 8 may be used together, the flow path for discharging the liquid may be one, and the pressure may be adjusted by the liquid extraction part 7 to reduce the gas-liquid mixture. In that case, the apparatus configuration is simplified.

  FIG. 7 is a conceptual explanatory diagram illustrating the mechanism by which the gas-liquid mixture is stabilized. As shown in the figure, a protective film M having a boundary film structure (crystal structure) is formed at the interface between the bubble B and the liquid Lq by bonding of strong water molecules such as ice or hydrate having a hydrogen bond distance shorter than usual. Therefore, it is considered that the mass transfer between the gas and liquid was prevented, and the bubbles became stable. The internal pressure of bubbles (nanobubbles) in the gas-liquid mixture of nitrogen, methane, and argon is about twice or more than the pressure obtained from the Young Laplace equation. As described above, the hydrogen bonding distance at the bubble interface is short and the internal pressure of the bubble is increased, so that the bubble becomes a stable gas-liquid mixture.

  The gas-liquid mixed liquid produced by the present invention holds a gas such as carbon dioxide, nitrogen, oxygen, ozone, or argon as a fine bubble in the liquid, and these gases are stably contained in the liquid at a high concentration. Therefore, it can be used in the environmental field, the manufacturing / industrial field, the energy field, the agriculture / forestry / fishery field, the food field, the household field, the medical field, and other various fields.

  For example, in the environmental field, the oxygen abundance in the water area is increased by supplying a gas-liquid mixture in which oxygen is bubbled and present in high concentrations in closed water areas such as the sea, rivers, lakes, ponds, and dam lakes. Water purification can be performed, and similarly, it can be used for oxygen supply in septic tanks, sewerage facilities, and human waste processing facilities. Moreover, harmful substances and oil contamination can be treated by supplying oxygen to the soil.

  In the manufacturing / industrial field, it can be used for cleaning precision parts and the like by jetting or dipping a gas-liquid mixture in which oxygen bubbles are present at a high concentration. In addition, by supplying a gas-liquid mixture in which oxygen bubbles are present at a high concentration to a factory wastewater treatment facility, wastewater treatment can be performed by improving the amount of oxygen, or ozone bubbles are present at a high concentration. By supplying the gas-liquid mixture, the waste water can be subjected to ozone treatment. Moreover, it can utilize for oxygen supply for fermentation and culture | cultivation promotion of fermented food in a food factory. It can also be used to supply oxygen and ozone to circulating water filtration systems such as commercial baths, pools, and aquariums. Oxygen and ozone for factory painting process circulating water, factory cleaning process circulating water, and cooling circulating water It can be used for purification by supply. Furthermore, a gas-liquid mixture is generated by mixing toxic gas generated in factories with water as bubbles, and the toxic gas is processed by processing the gas-liquid mixture in which this high-concentration toxic gas exists. You can also.

  In the energy field, natural gas, hydrocarbons such as methane, butane, ethane, propane, etc., oxygen, nitrogen, hydrogen, ozone, etc. are present in the liquid as bubbles, so that these gases are stably maintained at a high concentration. be able to. And, by cooling or compressing such a gas-liquid mixture, it is solidified or slurried to produce a gas hydrate, and by this gas hydrate, transportation of gas, storage and transportation of fresh food products, It can be used for plant cultivation, carbonated drinks, and fuel.

  In the agriculture, forestry and fisheries field, by supplying a gas-liquid mixture with high concentration of oxygen bubbles to agricultural, fishery and livestock wastewater, the oxygen content is improved and used for water purification and flotation separation of filth. be able to. In addition, by using a gas-liquid mixed solution in which oxygen bubbles are present at a high concentration as agricultural water or fishery water, it is possible to promote the germination and growth of plants and the growth of seafood. Furthermore, by supplying a gas-liquid mixed liquid in which oxygen bubbles are present at a high concentration in the ginger, oxygen can be supplied during transport of live fish. It can also be used for agricultural wastewater treatment.

  In the food field, gas-liquid mixtures containing bubbles such as oxygen and carbon dioxide can be used as food processing water and food washing water, and there are bubbles of inert gases such as nitrogen, helium, and argon. It can be used to prevent food spoilage using a gas-liquid mixture.

  In the household field, by supplying a gas-liquid mixed liquid in which oxygen bubbles are present at a high concentration to a domestic wastewater septic tank or the like, wastewater treatment by improving the amount of oxygen can be performed efficiently. Moreover, a carbon dioxide bath can be formed by supplying a gas-liquid mixed liquid in which bubbles of carbon dioxide exist at a high concentration to the bathtub. Moreover, a gas-liquid liquid mixture can be utilized for drinks and cosmetics.

  In the medical field, use gas-liquid mixtures with high concentrations of oxygen bubbles and gas-liquid mixtures with high concentrations of carbon dioxide bubbles for beverages, cancer treatment, stone destruction, etc. Can do.

  In other fields, a gas-liquid mixed solution can be used as oxygen water for beverages and carbonated water for beverages. Furthermore, a gas-liquid mixture can be used as ozone water used in various fields such as sterilization, decolorization, deodorization, and organic matter decomposition.

  And the gas-liquid mixed-liquid production | generation apparatus of this invention can be utilized as an apparatus which produces | generates the gas-liquid mixed liquid used for the above various fields, and is utilized as a household functional water production | generation apparatus. It can also be used as an apparatus for manufacturing a gas-liquid mixture for industrial use (gas-liquid mixture manufacturing apparatus).

  Hereinafter, the present invention will be described with reference to examples.

  FIG. 8 shows an example of a specific form of the gas-liquid mixed liquid generating apparatus. In FIG. 8, the upper housing 10 is shown in FIG. 8A and the front housing 10 is removed in FIG. 8B so that the inside of the apparatus can be seen.

  In this gas-liquid mixed liquid generating apparatus A, the gas supply unit 2 is composed of an ejector 35, the pressure mixing unit 1 is composed of a pump 11, and the pressure holding unit 3 is composed of a backflow prevention valve 32. The pressure adjusting unit 4 includes a pressure reducing on / off valve 33, and the pressure reducing on / off valve 33 is provided with a slow pressure reducing pipe 14 communicating with the outside. A gas hose 15 is attached to the gas discharge valve 34. The pump 11 uses a pump 11 a as shown in FIG. 2 and is configured to be driven by the rotation of the motor 16. Both the flow path 6 and the extraction flow path 7b are formed by a liquid hose. An attachment fitting 13 for attaching a hose to the water pipe is provided at the upstream end of the flow path 6. The ejector 35, the backflow prevention valve 32, the pump 11, the motor 16, the pressure reducing on / off valve 33, the gas discharge valve 34, the liquid storage tank 5, and a part of the flow path 6 are accommodated in the housing 10. The gas-liquid mixed liquid generating apparatus A can generate gas-liquid mixed water by injecting a gas such as air into water, and the generated gas-liquid mixed water can be used as water for beverages.

  Details of the device configuration will be described below.

Motor 16: AC100V induction motor Pump 11: Vane pump Liquid storage tank 5: Water storage tank, 1 MPa pressure resistance, 1 L capacity sealed tank (SUS314)
Gas discharge valve 34: Relief valve (open at 0.5 MPa or more)
Slow decompression tube 14: A narrow tube having an inner diameter of 1 mm and a length of 1 mm (a tube that gently decompresses and decompresses compressed gas).

  Using the apparatus of FIG. 8, pure water was used as the liquid, and various gases described later were used as the gas to generate a gas-liquid mixed solution. The operation of the apparatus is shown below.

The initial state is: ・ The pressure reducing on-off valve 33 is closed (setting to maintain the water tank 5 at 0.5 MPa)
・ The pump was stopped. ・ The extraction valve 7a (extraction valve) was closed.

Gas-liquid mixing (1) The water pipe was opened. This allowed water to enter the device.
(2) It was detected that water entered the apparatus, and the pump 11 was driven by the motor 16.
(3) When water passed through the ejector 35, the gas was sucked and the gas was injected into the liquid.
(4) Water and gas were mixed with the pump 11 on the conditions of pressure 0.5MPa, and the nanosized bubble was produced | generated in the liquid. The conditions for gas-liquid mixing are as follows.

・ Rotation speed of pump 11: 1700 rpm
・ Water flow rate: 6L / min
・ Gas intake volume 6L / min
-Pressure at the inlet of the pump 11: 0.1 MPa
-Pressure at the outlet of the pump 11: 0.6 MPa
・ Pressurization speed: ΔP ₁ /t=28.3 MPa
(5) The generated gas mixture was stored in the storage tank 5. The pressure in the tank was maintained at 0.6 MPa by the gas discharge valve 34.
(6) Upon detecting that the tank is full, the pump 11 was stopped. At this time, the inside of the tank was maintained at 0.6 MPa.
(7) Allow 0.5 seconds or more to pass.
(8) The pressure reducing on / off valve 33 was opened, and the pressure was gradually reduced by the slow pressure reducing pipe 14. The decompression speed conditions are
Decompression rate: ΔP ₂ / t = −5 MPa
It was.

In addition, it was found that if the time for returning from 0.6 MPa to atmospheric pressure 0.1 MPa is 0.5 seconds or more as a decompression time condition, nano-sized bubbles do not grow into micro-size or coalesce. . A gas-liquid mixed solution containing nano-sized bubbles is colorless and transparent, but can be distinguished because bubbles become white when the bubbles grow or coalesce to become micro-sized.
(9) After detecting that the pressure in the tank was reduced to atmospheric pressure, the extraction valve 7a was opened and the gas-liquid mixed water was taken out.

  Next, physical properties of the gas-liquid mixed solution generated as described above will be described.

[Hydrogen bond distance]
FIG. 9 shows an infrared absorption spectrum of a gas-liquid mixed solution (nitrogen mixed water) using nitrogen as a gas and pure water as a liquid and nitrogen saturated water in which nitrogen is dissolved in pure water at a saturated dissolution concentration. It is a graph which shows a difference. It is known that an infrared absorption band due to OH contraction vibration of water usually has an absorption maximum in the vicinity of 3400 cm ⁻¹ , but as shown in the graph, the gas-liquid mixture of the present invention has an absorption maximum of OH contraction vibration. Is shifted to around 3200 cm ⁻¹ . When the absorption maximum is 3400 cm ⁻¹ , the hydrogen bond distance is 0.285 nm. On the other hand, when the absorption maximum is 3200 cm ⁻¹ , the hydrogen bond distance is known to be 0.277 nm, which is shorter than the normal hydrogen bond distance under normal temperature and pressure, and is structured ice or hide. It was concluded that the water was close to the rate.

[Gas volume]
The amount of gas present as bubbles in a gas-liquid mixture using pure water as a liquid and nitrogen, hydrogen, methane, argon, or carbon dioxide as a gas was measured by the following method.
(1) Various gases were mixed with pure water having a conductivity of 0.1 μS / cm at 25 ° C. to obtain a gas-liquid mixture.
(2) In order to separate large bubbles having a diameter of 1 μm or more from water, the gas-liquid mixture was allowed to stand at 25 ° C. for 1 day. As for the standing time, from the Stokes' law, the bubble rising speed: V = d ² × g / (18 × γ)
(D: bubble diameter, g: gravitational acceleration, γ: kinematic viscosity coefficient)
From this equation, the rate of rise of bubbles of 1 μm is about 2.4 × 10 ⁻⁴ m / s. For example, if the water depth of the container at the time of standing is 50 mm, Bubbles can be removed.
(3) The mass of the gas-liquid mixture was measured with an analytical balance having a minimum measured value of 1 mg.
(4) A gas-liquid mixture and a stirrer of a stirrer are placed in a PE + nylon resin vinyl bag with low gas permeability and moisture permeability, and the vinyl bag is sealed with a sealer in a state where there is no air in the bag. .
(5) Immediately after sealing, the mass of the vinyl bag in which the gas-liquid mixture was sealed was measured with an analytical balance.
(6) The vinyl bag in which the gas / liquid mixture at 25 ° C. was sealed by a hot stirrer was heated to 45 ° C., and the gas / liquid mixture was stirred for about 5 hours. By this temperature rise and stirring, fine bubbles and gas dissolved at a saturated dissolution concentration of 45 ° C. or higher were separated from the gas-liquid mixture and collected on the top of the vinyl bag.
(7) The set temperature of the hot stirrer was set to 25 ° C. at room temperature of 25 ° C., and the mixture was stirred for several hours so as to become a liquid having a saturation solubility of 25 ° C.
(8) Using an analytical balance, the mass of the vinyl bag in which gas and liquid were enclosed was measured.
(9) The mass of the gas-liquid mixture and the amount of change in the mass of the liquid caused by the buoyancy caused by the gas separated from the gas-liquid mixture by heating and stirring were obtained from three mass measurements. The mass change amount is the same as the mass of air having the same volume as the gas volume separated from the gas-liquid mixture, and the volume and mass of the separated gas can be calculated from this value.

  FIG. 10 is a graph showing the gas volume measured in this way. The lower region of each bar graph is the amount of gas that was present as the measured bubble, and the upper region is the saturated amount of gas that follows Henry's law. As shown in the graph, for example, in the case of a gas-liquid mixture using hydrogen and water, 17.6 mL of hydrogen is dissolved in 1 L of pure water at 25 ° C. as a saturated dissolution amount, and 528 mL of gas exists as fine bubbles. It was confirmed. That is, the amount of gas contained in the gas-liquid mixture was 30 times the amount of supersaturated dissolution. Similarly, the amount of gas contained in the gas-liquid mixture with respect to the amount of supersaturated dissolution was 36 times for nitrogen, 17 times for methane, 16 times for argon, and 1.9 times for carbon dioxide. As described above, the gas-liquid mixed liquid can hold the gas in the liquid at a high concentration equal to or higher than the saturated dissolution concentration, and the high-concentration gas-liquid mixed liquid can be used in various fields. is there.

[Bubble size]
The gas-liquid mixture produced in the same manner as above was instantly frozen, cleaved with a cutter in a vacuum, and methane / ethylene was allowed to flow through the fractured surface to discharge, producing a hydrocarbon film (replica film) with transferred irregularities . A conductive osmium thin film was applied to the replica film, dried sufficiently, and observed with a scanning electron microscope (SEM).

  FIG. 11 is an example of a photograph observed by SEM for a gas-liquid mixture of nitrogen and pure water. Similarly, by observing photographs, it was confirmed that when nitrogen, hydrogen, methane, argon, carbon dioxide was used as the gas, the bubble size of the gas-liquid mixture was 100 nm in diameter distribution peak. The bubbles in the gas-liquid mixture of the above gas and pure water could not be accurately detected by a particle size distribution measuring apparatus such as a dynamic scattering method using a laser.

[Internal pressure of bubbles]
The pressure inside the bubbles was calculated from the total amount of gas in the gas-liquid mixture. Table 1 shows the total amount of gas and the internal pressure of bubbles calculated from the total amount of gas in a gas-liquid mixed solution of nitrogen, methane, or argon and 25 ° C. pure water.

The internal pressure of the gas in the bubbles is calculated by the following method.
The equation of state of gas is
PV / T = (const)
(P: internal pressure, V: volume, T: internal temperature)
When T is constant, PV = (const)
It is represented by

And the volume of bubbles in the gas-liquid mixture can be calculated from the density of the gas-liquid mixture,
The relationship of atmospheric pressure × total gas volume = bubble internal pressure × total gas volume in liquid is established, and the internal gas pressure in the bubbles is calculated by applying the above measured gas amount to this relational expression. The pressure value is as follows.

For example, if the gas is nitrogen,
Assuming that the volume of water in 1 liter of gas-liquid mixture is w1 liter and the volume of gas in water is w2 liter,
The following relational expression holds for the volume.

w1 + w2 = 1 liter (Formula A)

In addition, the following relational expression holds for the mass.

w1 × density of water + w2 ÷ 22.4 (liter) × 28 (nitrogen molecular weight) = measured mass (Formula B)
Water density: 997.1g / L for pure water at normal temperature and pressure
22.4 liters: volume of 1 mol of gas Measured mass: 988.3 as shown in Table 1

Solving the above two equations (Equations A and B),
Since w2 = 8.84 × 10 ^ (-3) is calculated,
Internal pressure of gas = atmospheric pressure x total volume of gas ÷ total volume of gas in liquid
= 0.1 x (value in Table 1) / w2
= 0.1 × 0.56 ÷ (8.84 × 10 ^ (-3))
= 6.3 MPa
It becomes.

  In the above calculation, it was assumed that the internal temperature of the bubble was constant (normal temperature), but the actual internal temperature of the bubble is also expected to be higher than the atmospheric temperature (normal temperature). It can be predicted from the gas state equation that the pressure is higher than the above calculation result.

  By the way, in general, the internal pressure of bubbles is calculated as follows. The bubbles are pressurized by the interfacial tension between the gas-liquid interface, and this interfacial tension is derived by Young Laplace's equation (the following equation).

ΔP = 2σ / r
(ΔP: rising pressure, σ: surface tension, r: bubble radius)
According to this equation, for example, in the case of a bubble having a diameter of 100 nm, the bubble internal pressure is 3 MPa.

  On the other hand, the internal pressure in the gas-liquid mixed liquid is 6.3 MPa in the case of nitrogen, for example, as shown in Table 1. In this gas-liquid mixed liquid, bubbles having a diameter of 100 nm are dispersed as shown in the SEM photograph. Therefore, it was confirmed that the bubbles of the gas-liquid mixture had an internal pressure that was about twice or more the value calculated from the Young Laplace equation. Therefore, it was concluded that a stronger interface structure was formed at the bubble interface.

[Bubble distribution]
The amount of bubble distribution (number) was calculated from Table 1.

When the gas is nitrogen, the total amount of bubbles returned to the atmosphere (0.1 MPa) is 0.56 L, and the internal pressure of the bubbles is 6.3 MPa. Therefore, the total volume V1 of bubbles in water is assumed to change isothermally, PV From = const
V1 = 0.56 × 0.1 ÷ 6.3
It becomes.

Since the bubbles are spheres with a radius r = 50 nm, the volume V2 per bubble is
V2 = 4/3 × π × r ^ 3
It becomes.

  From the above, the number of bubbles per liter of water n = V1 ÷ V2 = 1.7 × 10 ^ 16 is calculated.

  Similarly, the number of bubbles per liter of water is calculated as 1.8 x 10 ^ 16 when the gas is methane and 1.7 x 10 ^ 16 when argon is used.

[Stability of gas-liquid mixture]
FIG. 12 shows the supersaturation as the gas abundance ratio in the gas-liquid mixture with respect to the saturated dissolution concentration when the gas-liquid mixture produced by mixing air with pure water is sealed in a glass bottle and stored at a constant temperature. It is a graph to display. From the graph, it can be seen that the degree of supersaturation is almost constant even after 400 hours, and hardly changes. Therefore, it was confirmed that the gas-liquid mixture was stable.

DESCRIPTION OF SYMBOLS 1 Pressurization mixing part 2 Gas supply part 3 Pressure holding part 4 Pressure adjustment part 5 Liquid storage tank 6 Flow path 7 Extraction part 8 Liquid discharge part 11 Pump 12 Venturi pipe 21 Rotating body

Claims (7)

  By supplying a gas to the liquid, the liquid and the gas are mixed while pressurizing the liquid supplied with the gas at a pressurization speed of 0.17 MPa / sec or more, and the pressure of the liquid is set to 0.15 MPa or more to achieve nano size. To form a pressurized gas-liquid mixture, store the gas-liquid mixture in a sealed state in a sealed state while maintaining the pressurized state, and store it in the liquid tank. A gas-liquid mixed liquid in which nano-sized bubbles are mixed with a liquid is generated by reducing the pressure of the liquid-liquid mixed liquid to atmospheric pressure at a pressure reduction rate of 2000 MPa / sec or less. A method for producing a liquid mixture.   The method for producing a gas-liquid mixture according to claim 1, wherein the liquid is pressurized and mixed by a pump.   The method for producing a gas-liquid mixture according to claim 2, wherein the pump pressurizes and mixes the liquid using a rotating body while shearing the liquid.   The method for producing a gas-liquid mixture according to claim 1, wherein the liquid is pressurized and mixed by a venturi tube.   A gas supply unit that supplies a gas to the liquid, and the liquid and the gas are mixed while pressurizing the liquid supplied with the gas at a pressurization speed of 0.17 MPa / sec or more to make the liquid pressure 0.15 MPa or more. A pressure mixing unit that generates a gas-liquid mixture in a pressurized state, a liquid storage tank that stores the gas-liquid mixture generated in the pressure mixing unit in a sealed state, and a pressure state of the gas-liquid mixture And a pressure adjusting unit that adjusts the pressure of the gas-liquid mixed liquid stored in the liquid storage tank, and the pressure adjusting unit has a predetermined amount of gas-liquid stored in the liquid storage tank. A gas-liquid mixed liquid generating apparatus characterized in that the pressure of a mixed liquid is adjusted so as to be reduced to atmospheric pressure at a reduced pressure speed of 2000 MPa / sec or less.   The pressure holding unit is provided in a flow path for sending out the liquid at the front stage or the rear stage of the pressure mixing unit, and when the gas liquid mixture is generated in a predetermined amount and the driving of the pressure mixing unit is stopped, 6. The gas-liquid mixture generation apparatus according to claim 5, wherein the pressurized state is maintained.   The pressure adjusting unit maintains the pressure of the gas-liquid mixture in a pressurized state stored in the liquid storage tank at least while the pressure mixing unit is driven. The gas-liquid mixed-liquid production | generation apparatus of description.