JP2007000847A - Apparatus for generating fine bubble - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for generating fine bubbles, in which the efficiency when a gas is dissolved in a liquid in a gas dissolving tank can be improved while miniaturizing the apparatus for generating fine bubbles. <P>SOLUTION: The apparatus 1 for generating fine bubbles is provided on a flow passage 2, in which the liquid flows, with: a gas mixing part 3 for mixing the gas in the liquid flowing in the flow passage 2 to obtain a gas-mixed liquid; a pump 4 for pressurizing the gas-mixed liquid and sending the pressurized gas-mixed liquid to the flow passage 2; the gas dissolving tank 5 which has a liquid phase part 10 and a gas phase part 11 of an indissoluble gas therein, to which the gas-mixed liquid is supplied and which is used for dissolving the gas in the liquid to obtain the gas-dissolved liquid; and a fine bubble generating part 6 for releasing the gas from the gas-dissolved liquid and generating fine bubbles. A bubble generating means is arranged in the gas dissolving tank 5 for generating bubbles from the gas and the liquid. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a microbubble generator.

  2. Description of the Related Art Conventionally, as disclosed in Patent Document 1, for example, as disclosed in Japanese Patent Application Laid-Open No. H10-133707, a microbubble generating device that generates a fine bubble by once dissolving a gas in a liquid and then precipitating the gas from the liquid is generated. A gas mixing part for obtaining a gas mixed liquid by mixing the gas flowing into the liquid, a pump for pressurizing the gas mixed liquid and flowing it to the flow path, and having a liquid layer and a gas layer inside and supplying the gas mixed liquid to the gas There are provided a gas-liquid dissolution tank for dissolving a gas in a liquid to obtain a gas-dissolved liquid, and a fine bubble generating part for generating a fine bubble by depositing a gas in the gas-dissolved liquid.

Here, in order to obtain the effect of the fine bubbles, it is necessary to generate a large amount of fine bubbles, which is largely dependent on the amount of gas dissolved in the liquid in the gas-dissolved liquid, that is, the gas in the gas-liquid dissolution tank. The dissolution efficiency in the liquid is an important factor in the microbubble generator. In addition, it is known that the dissolution of a gas into a liquid, for example, can dissolve a larger amount of gas into a liquid as it is performed at a higher pressure. However, a pump that sends a gas mixture to a gas-liquid dissolution tank has a higher output. Although it is possible to improve the dissolution efficiency of the gas in the gas-liquid dissolution tank by using the one, in this case, there is an adverse effect that the fine bubble generating device is enlarged by a high output pump. there were.
JP-A-6-205812

  The present invention has been made in view of the above-described conventional problems, and provides a microbubble generator capable of improving the efficiency of gas dissolution in a gas-liquid dissolution tank while reducing the size of the apparatus. This is a problem.

  In order to solve the above-mentioned problem, the fine bubble generating apparatus according to claim 1 of the present invention includes a gas mixing unit 3 for obtaining a gas mixed liquid by mixing a gas into the liquid flowing through the flow path 2 into the flow path 2 through which the liquid flows. , A pump 4 that pressurizes the gas mixture liquid and flows it to the flow path 2, and has a liquid layer 10 and an undissolved gas gas layer 11 inside, and a gas mixture liquid is supplied to dissolve the gas in the liquid, thereby dissolving the gas. A gas-liquid dissolution tank 5 is provided, and a micro-bubble generating device 1 provided with a micro-bubble generating unit 6 that deposits gas in a gas-dissolved liquid to generate micro-bubbles. A bubble generating means for generating bubbles from the liquid is provided. According to this, since the foam produced by enclosing the gas in the liquid film is generated by the foam generation means, the area of the gas-liquid interface 17 between the gas layer 11 and the liquid layer 10 in the gas-liquid dissolution tank 5 is more than the area. It is possible to increase the contact area of the gas and liquid, and to improve the dissolution efficiency. However, it is not necessary to use the high-output pump 4 to improve the dissolution efficiency of the gas into the liquid. In addition, the low-power pump 4 can be used, and the microbubble generator 1 can be downsized.

  The present invention generates bubbles by enclosing gas with a liquid film in a gas-liquid dissolution tank, so that the gas-liquid contact exceeds the area of the gas-liquid interface between the gas layer and the liquid layer in the gas-liquid dissolution tank. Since it was possible to improve the dissolution efficiency by increasing the area, it is not necessary to use a high-power pump to improve the dissolution efficiency of gas into the liquid, and a low-power pump can be used. There is an advantage that the generator can be miniaturized.

  Hereinafter, the present invention will be described based on embodiments shown in the accompanying drawings.

  The fine bubble generating device 1 of this example is a device that supplies fine bubbles to the bathtub 7 as shown in FIG. 2. Specifically, the bathtub 7 is provided with a suction port 8 and a discharge port 9. A circulation flow path 2a, which is a flow path 2 from the suction port 8 to the discharge port 9, is formed, and gas is mixed into the bath water, which is a liquid, in order from the suction port 8 side to the circulation flow path 2a. The gas mixture 3 is obtained, the pump 4 transports bath water from the suction port 8 to the discharge port 9 through the circulation flow path 2a, and the gas mixture is supplied by the pump 4 so that the gas is dissolved in the bath water to dissolve the gas. It is formed by providing a gas-liquid dissolution tank 5 for obtaining a liquid and a fine bubble generating section 6 for generating fine bubbles by precipitating a gas in the gas-dissolved liquid. Here, in this example, the gas mixing unit 3 has a structure in which air is sucked and mixed into the bath water by the ejector effect of the bath water flowing through the circulation flow path 2a. A structure in which air is mixed into the bath water may be used. Moreover, as gas mixed in bath water, things other than air, for example, air with a high oxygen component, etc. can also be used. The fine bubble generating unit 6 is configured by a constricted portion with a reduced diameter of the circulation flow path 2a, and gas is deposited by reducing the pressure of the gas-dissolved liquid at the constricted portion. By the way, the present invention is characterized in that the gas-liquid dissolution tank 5 can improve the dissolution efficiency of the gas into the liquid without increasing the internal pressure of the gas-liquid dissolution tank 5 using the high-power pump 4. This will be described below.

  As shown in FIG. 1, the gas-liquid dissolution tank 5 of this example is a gas layer 11 in which the lower part of the hollow interior is a liquid layer 10 and the upper part is undissolved air. 5 is provided with an inlet 12 through which gas mixture liquid is supplied into the gas-liquid dissolution tank 5. The gas bubble-dissolution tank 5 reaches the fine bubble generation unit 6 at the lower end of the side wall. An outlet 13 is provided to which the circulation channel 2a is connected and from which the gas-dissolved liquid is discharged. Then, bubbles are generated in the gas-liquid dissolution tank 5 by the bubble generating means.

  In other words, the jet stream 14 of the gas mixture liquid is diverged through the nozzle 22 provided at the inlet 12 of the gas-liquid dissolution tank 5, and the divergent jet stream 14 is spread through the gas layer 11. The gas-liquid interface 17 is reached at the end portion in the above state. Here, the part of the gas-liquid interface 17 where the jet flow 14 reaches is referred to as an injection area 15, and the part of the gas-liquid interface 17 where the injection flow 14 does not reach is referred to as a non-injection area 16 (FIG. 1B). Thus, since the jet flow 14 is diverged to reach the gas-liquid interface 17 at the end thereof, the outer edge length 20 in the portion of the jet flow 14 reaching the gas-liquid interface 17 can be secured long, that is, The collision length between the jet stream 14 and the gas layer 11 and the liquid layer 10 can be increased, and the gas in the gas layer 11 is made to flow into the liquid layer 10 and the jet stream by the impact of the collision with the jet stream 14, the gas layer 11 and the liquid layer 10. 14 to be able to generate a large amount of foam. That is, the foam generating means of this example is constituted by the nozzle 22 provided at the inlet 12 of the gas-liquid dissolution tank 5 for forming the divergent jet flow 14.

  In addition, since the jet direction of the outer edge portion in the divergent jet flow 14 is directed not only in the direction perpendicular to the gas-liquid interface 17 (downward) but also in the in-plane direction (horizontal direction) of the gas-liquid interface 17, According to the jet flow 14, it is possible to generate a swirl flow 18 that goes to the adjacent non-jet region 16 immediately after the collision with the gas-liquid interface 17. In particular, at the gas-liquid interface 17 of the gas-liquid dissolution tank 5 of this example, the non-injection area 16 is divided by the injection area 15, and the swirl flow 18 is stabilized without loss toward the divided non-injection area 16. It is intended to form into a flow. Thus, even if the generated bubbles are drawn into the liquid layer 10 by the momentum of the jet flow 14, the swirl flow 18 can be lifted up in the non-injection region 16, that is, after the generation, The drawn bubble can also immediately appear at the gas-liquid interface 17.

  As described above, the generation of bubbles due to the rush of the jet flow 14 into the gas-liquid interface 17 is continuously performed during the operation of the fine bubble generating device 1, and the jet flow 14 is expanded into a bubble shape. Generation efficiency is increased, and the bubbles drawn into the liquid layer 10 are immediately made to appear at the gas-liquid interface 17 by the swirling flow 18, so that a large amount of bubbles are efficiently generated in the gas-liquid dissolution tank 5. It is. Here, since the bubbles are encased in a liquid film, the contact area between the liquid and the gas can be increased by generating the bubbles, and thus the dissolution efficiency of the gas in the liquid It was possible to improve. Here, the gas-liquid interface 17 is in a undulating state due to the impact of the jet stream 14 entering the gas-liquid interface 17. According to the undulating gas-liquid interface 17, the bubbles in contact with the gas-liquid interface 17 are liquidated. It can be easily taken into the layer 10 and dissolved, and this also improves the dissolution efficiency of the gas into the liquid. In addition, when the generated bubbles are drawn into the liquid layer 10, the volume of the liquid layer 10 increases. However, the liquid layer 10 that has increased in volume does not reach the jet stream 14 at the gas-liquid interface 17. The area of the gas-liquid interface 17 itself increases from the region 16 toward the gas layer 11 (the gas-liquid interface 17 indicated by the dotted line in the figure), and this also improves the dissolution efficiency of the gas into the liquid. It is shown. In the first place, since the jet flow 14 is composed of a gas mixed liquid in which gas is mixed in the liquid as bubbles, the bubbles originally contained in the jet flow 14 are also contained in the gas-liquid dissolution tank 5. Needless to say, this contributes to improving the efficiency of foam generation.

  Furthermore, it is also preferable to fill the gas layer 11 with a large amount of bubbles generated efficiently as described above. That is, in the bubble layer 19 formed of bubbles, the thicker the layer, the larger the contact area of the gas / liquid other than the gas / liquid interface 17, which is preferable because the dissolution efficiency can be improved. In order to increase the bubble generation efficiency and increase the bubble layer 19, the void ratio of the gas mixture liquid (volume ratio of the bubbles mixed in the liquid to the gas mixture liquid) is set to 50% or less, and the gas-liquid interface of the jet 14 As the injection pressure to 17 and the area of the gas layer 11 in the gas-liquid dissolution tank 5 were larger, better experimental results could be obtained. In this example, since the inlet 12 is provided facing the gas layer 11, in the case where the gas layer 11 is filled with the bubble layer 19, the divergent jet flow 14 from the inlet 12 causes the bubble layer 19 to flow. The outer edge surface 21 of the jet flow 14 that is formed in a divergent shape and can be brought into contact with the bubble of the bubble layer 19 can be brought into contact with the bubble of the bubble layer 19. Therefore, it is possible to increase the gas-liquid contact area in the jet flow 14 and improve the dissolution efficiency of the gas into the liquid.

FIG. 3 shows another embodiment of the present invention. In this example, the circulation flow path 2 a extending from the pump 4 is connected to the bottom wall of the gas-liquid dissolution tank 5, and the inlet 12 through which the gas mixed liquid is supplied into the gas-liquid dissolution tank 5 is provided so as to face the liquid layer 10. At the same time, the nozzle 22 constituting the bubble generating means is formed at the inlet 12, and the gas mixture liquid is formed into a divergent jet flow 14 at the nozzle 22 and directed toward the gas-liquid interface 17 through the liquid layer 10. The remaining portion is the same as the previous example. Also in this example, since the divergent jet flow 14 reaches the gas-liquid interface 17 at the end portion in the spread state, the outer edge length 20 in the portion of the jet flow 14 reaching the gas-liquid interface 17 is increased. Can be secured for a long time, and the gas in the gas-liquid dissolution tank 5 can be generated by entraining the gas in the gas layer 11 in the jet flow 14 or the liquid layer 10 to generate a large amount of bubbles, increasing the contact area of the gas-liquid. It was possible to improve the dissolution efficiency in the liquid.

  In the fine bubble generating apparatus 1 in the above embodiment, the gas-liquid dissolution tank 5 has an increased dissolution efficiency between gas and liquid, and thus increases the dissolution efficiency of the gas-liquid dissolution tank 5 that has been generally performed conventionally. In other words, it is not necessary to use the high-output pump 4, and the enlargement of the microbubble generator 1 associated with the use of the high-output pump 4 can be avoided. It is. This is particularly useful when the fine bubble generator 1 must be installed in a limited space such as in a bathroom, such as the fine bubble generator 1 that supplies fine bubbles to the bathtub 7. Of course, the fine bubbles generated by the fine bubble generator 1 have a low ascent rate and can stay in the liquid for a long time, and in the state where the fine bubbles are contained in the liquid, it is possible to obtain a white turbid appearance like hot spring water. In addition, since the surface area per volume is large and the dirt in the liquid is adsorbed and floated, the water quality can be purified, so that fine bubbles are supplied not only to the bathtub 7 but also to the septic tank and the skein. Of course, in this case, it is needless to say that the space can be saved by reducing the size of the microbubble generator 1.

Moreover, in the fine bubble generator 1 in the above embodiment, the example in which the bubble generating means is configured by the nozzle 22 that forms the divergent jet flow 14 is illustrated. However, as the bubble generating means, for example, gas in the gas layer is used. A means for stirring the liquid layer or a means for adding a chemical that contributes to foam generation to the gas mixed liquid may be used. In short, any means for generating and promoting foam in the gas-liquid dissolution tank 5 can be used as appropriate. is there.

BRIEF DESCRIPTION OF THE DRAWINGS It is a fine bubble generator of the example of embodiment of this invention, (a) is a sectional side view of the principal part, (b) is a top view of the gas-liquid melt | dissolution tank explaining an injection area | region and a non-injection area | region It is. It is a whole schematic block diagram of the fine bubble generator same as the above. It is a sectional side view of the principal part of the fine bubble generator of the other example of embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fine bubble generator 2 Flow path 2a Circulation flow path 3 Gas mixing part 4 Pump 5 Gas-liquid dissolution tank 6 Fine bubble generation part 10 Liquid layer 11 Gas layer 14 Injection flow 15 Injection area 16 Non-injection area 17 Gas-liquid interface 18 Turning Flow 19 Bubble layer 20 Outer edge length 22 Nozzle

Claims (1)

  A gas mixing section that mixes gas into the liquid flowing through the flow path to obtain a gas mixed liquid, a pump that pressurizes the gas mixed liquid and flows it through the flow path, and a liquid layer and an undissolved gas inside A gas-liquid dissolution tank that has a layer and is supplied with a gas mixed liquid to dissolve the gas in the liquid to obtain the gas-dissolved liquid, and a fine bubble generation unit that precipitates the gas in the gas-dissolved liquid and generates fine bubbles A fine bubble generating device comprising a bubble generating means for generating bubbles from gas and liquid in a gas-liquid dissolution tank.

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