JP4982450B2 - Microbubble generator - Google Patents

Description

  The present invention relates to a microbubble generator for generating microbubbles called microbubbles.

  Microbubbles injected into water with a bubble diameter of about 100 μm are called microbubbles, and based on their chemical or physical characteristics, various effects such as sterilization effects and frictional resistance reduction effects can be obtained. Therefore, it is expected to be used in various industrial fields.

  Various types of microbubble generators that generate such microbubbles are known. For example, in the apparatus according to Patent Document 1, microbubbles are generated by supplying gas through a porous body from a gas supply means such as a compressor to a pipe through which water flows.

In addition, in the apparatus according to Patent Document 2, a pressurized liquid introduction port is provided on the peripheral surface portion near the bottom surface, a gas introduction hole is provided on the bottom surface side, and a top portion of the rotation container body is provided on the cone-shaped rotation container body. Has a structure in which a swirling gas-liquid outlet hole is provided. Then, a large shearing force is applied to the bubble surface by utilizing the difference in swirling speed between the liquid and the gas heading toward the outlet hole while turning, and a large amount of minute air is pulled off from the outlet hole by this shearing force. Air bubbles are generated.
JP-A-8-2225094 JP 2003-205228 A

  However, in the case of the apparatus according to Patent Document 1, since the bubbles are difficult to separate from the porous body, the generated bubbles are larger than the pore diameter of the porous body, and there is a disadvantage that sufficiently small bubbles cannot be obtained. ing.

  In addition, in the case of the device according to Patent Document 2, fine bubbles can be obtained as compared with Patent Document 1, but since it is necessary to give a swirl flow to the liquid, the pressure loss increases and the gas in the liquid This ratio has a disadvantage that it is lower than that of Patent Document 1.

  Thus, in general, in the conventional microbubble generator, the bubble diameter and the required energy are in a so-called trade-off relationship. In other words, if it is attempted to generate bubbles having a sufficiently small bubble diameter, a large amount of energy is required. On the other hand, if energy is reduced, only bubbles having a large bubble diameter can be obtained.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a microbubble generator capable of efficiently generating microbubbles having a sufficiently small bubble diameter with a small amount of energy.

In order to solve the above problems, the present invention provides:
A disk member that is disposed in the water to be injected with microbubbles, has a cavity formed therein, and has a plurality of bubble injection holes formed on the disk surface, and an air supply line for the cavity of the disk member Air supply means for supplying air through, and motor means for rotationally driving the disk member, and a large number of bubble injection holes formed on the disk surface of the disk member include bubbles when the disk member rotates. In the microbubble generator formed in the setting region where the peripheral speed of the injection hole is equal to or higher than a predetermined speed,
The disk member and the motor means are disposed in a vertically placed state with the disk member positioned on the lower side, and the disk surface on which the plurality of bubble injection holes are formed is disposed on the upper surface of the disk surface facing the motor means. And
And a sliding contact member disposed in the bubble injection hole of the disk member so as to slide in contact with the disk surface of the setting region in the water .

  According to the present invention, a large number of bubble injection holes formed on the disk surface of the disk member are configured to be formed in a setting region where the peripheral speed of the bubble injection hole during rotation of the disk member is equal to or higher than a predetermined speed. Therefore, it is possible to efficiently generate microbubbles having a sufficiently small bubble diameter with a small amount of energy.

  FIG. 1 is a configuration diagram of a first embodiment of the present invention. A water tank 2 is installed on the floor 1, and water 3 is stored in the water tank 2. A support leg 4 is disposed on the bottom surface of the water tank 2, and an underwater motor 5 as a motor means is attached to the support leg 4.

  The tip of the rotating shaft 6 of the submersible motor 5 is attached to the upper side of the rotary joint 7, and one end side of the air supply pipe 8 is attached to the lower side of the rotary joint 7. The other end side of the air supply pipe 8 is attached to a disk member 9. One end side of the air supply line 10 is connected to the side surface of the rotary joint 7. The other end side of the air supply line 10 is connected to a blower 11 as air supply means. When the blower 11 is activated, air is supplied to the hollow portion of the disk member 9 via the air supply line 10, the rotary joint 7, and the air supply pipe 8.

  2A and 2B are explanatory views showing the structure of the disk member 9 in FIG. 1, wherein FIG. 2A is a longitudinal sectional view of the disk member 9 and the air supply pipe 8, and FIG. 2B is a view taken along the line BB in FIG. It is.

  As shown in FIG. 2A, the other end side of the air supply pipe 8 communicating with the hollow portion 9a is connected to the center portion on the upper surface side of the disk member 9. A large number of bubble injection holes 9 b are formed on the upper surface side of the disk member 9. Therefore, the air sent from the blower 11 via the air supply line 10 and the rotary joint 7 is supplied into the hollow portion 9a from the other end side of the air supply pipe 8, and further from a large number of bubble injection holes 9b. Microbubbles will be injected into the water.

  As shown in FIG. 2 (b), a large number of bubble injection holes 9 b are formed in a set region R set in a donut shape near the periphery of the disk surface on the upper surface side of the disk member 9. This set region R is set as a region in which the peripheral speed of the bubble injection hole 9b during the rotation of the disk member 9 is equal to or higher than a predetermined speed. These bubble injection holes 9b are formed at a predetermined pitch P on the same concentric circle for each of a plurality of radii R1, R2, R3.

  Next, the operation of FIG. 1 will be described. When the submersible motor 5 starts to rotate and the blower 11 is activated, the air taken into the blower 11 from the atmosphere passes through the air supply line 10, the rotary joint 7, and the air supply pipe 8 to the disk member 9. It is supplied to the cavity 9a. And the air with which the cavity part 9a was filled is inject | poured in water as a microbubble from many bubble injection holes 9b.

  At this time, the microbubbles generated from the bubble injection hole 9b and about to be injected into the water have a shearing force generated by the relative motion between the rotating disk member 9 and the water existing around the disk member 9. Under the action, it is peeled off from the bubble injection hole 9b and injected into water. The magnitude of the shearing force at this time is large because the bubble injection hole 9b is formed in the set region R and rotates at a high speed. Therefore, the microbubbles in the state of being exposed from the bubble injection hole 9b are immediately torn off from the bubble injection hole 9b with a strong shearing force before growing into a bubble having a large diameter, and are kept in the water while maintaining the fine state. Injected. That is, according to the configuration of the present embodiment, it is possible to efficiently generate microbubbles having a sufficiently small bubble diameter with a small amount of energy.

  Next, specific numerical values of various data in the present embodiment will be described. In the present embodiment, a large number of bubble injection holes 9b formed on the disk surface of the disk member 9 are formed in a setting region R in which the peripheral speed of the bubble injection hole 9b during rotation of the disk member 9 is equal to or higher than a predetermined speed. However, the predetermined speed is 6 [m / s] in the present embodiment. The rotation speed of the submersible motor 5 (either variable speed or constant speed) and the width of the setting region R are set so that the peripheral speed of all the bubble injection holes 9b is 6 [m / s] or more. There is a need.

  The inventor of the present application experimented with various changes in the diameter of the bubble injection hole 9b in the range of 0.1 to 1 mm, but when the peripheral speed is 6 [m / s] or more, the range is within this range. Regardless of the pore size, microbubbles of about 100 μm (0.1 mm) could be obtained.

  Moreover, it is preferable that the value of the pitch P in FIG.2 (b) shall be 15 mm or more. As a result of the experiment, it was confirmed that, at a pitch P smaller than this, the microbubbles separated from the adjacent bubble injection holes 9b merged to grow into bubbles having a large diameter.

  By the way, in this embodiment, it is assumed that the bubble injection hole 9b is a circular hole having a hole diameter of 0.1 to 1 mm, but an n-gon (that is, a polygon) inscribed in the diameter of these circular holes. ), Microbubbles having a smaller diameter can be obtained. The reason for this will be described with reference to FIG.

  As shown in FIG. 3A, let us consider a state just before the microbubbles 12 appear in water from the bubble injection hole 9b and are about to be peeled off. In this state, the shearing force F acting on the microbubbles 12 and the adhesion force Fb of the microbubbles 12 to the bubble injection hole 9b are balanced, and F = Fb. One method for separating the microbubbles 12 from the bubble injection hole 9b is to pay attention to the shearing force F and to increase F so that F> Fb. Further, this can be realized by setting the peripheral speed of the bubble injection hole 9b to a predetermined speed (6 [m / s]) or more.

  Then, another method for peeling the microbubbles 12 from the bubble injection hole 9b is to pay attention to the adhesive force Fb and to reduce Fb so that F> Fb. Here, the adhesion force Fb is Fb = P * σ, where P is the length of the microbubbles 12 attached (that is, the inner circumference of the bubble injection hole 9b), and σ is the surface tension of the microbubbles 12. Can be expressed as Since the surface tension σ is a physical property value of water and is constant, the inner circumferential length P of the bubble injection hole 9b may be shortened in order to reduce the adhesive force Fb.

  Therefore, as shown in FIG. 3B, when the bubble injection hole 9b is a circular hole having a diameter D1, as shown in FIG. 3C, a rectangular shape (inscribed in a circle having a diameter D1) If the bubble injection hole 9b of n = 4) is used, the inner peripheral length of the rectangular bubble injection hole 9b is shorter than that of the circular shape, so that the adhesive force Fb can be further reduced. In FIG. 3C, an example of a rectangular bubble injection hole 9b with n = 4 is shown, but a triangular shape with n = 3 or a pentagonal shape with n = 5 may be used. However, if the value of n is too large, the n-gonal shape becomes close to a circle and is meaningless. Therefore, practically, the value of n is preferably in the range of n = 3-6.

  Here, in the configuration of FIG. 1 described above, the disk member 9 and the submersible motor 5 are arranged in a vertically placed state in which the disk member 9 is located on the lower side, and the disk surface on which a large number of bubble injection holes 9b are formed is It is a board surface on the upper surface side facing the submersible motor 5. As described above, by providing both the disk member 9 and the submersible motor 5 in the water tank 2, the effects of simplification of the structure and space saving can be obtained.

  That is, prior to the filing of the present application, the inventors of the present application have proposed a configuration in which the disk member is disposed near the bottom of the water tank and the motor means is disposed below the water tank bottom (outside the water tank). PCT / JP2008 / 59448). However, in such a configuration, since the water leakage around the rotating shaft of the motor means penetrating the bottom of the water tank must be prevented, the structure is complicated, and a space for arranging the motor means is provided below the bottom of the water tank. Therefore, the degree of freedom in design is impaired to some extent. According to the configuration of the first embodiment of FIG. 1 described above, such inconvenience can be avoided (the same applies to the configurations of the second and subsequent embodiments thereafter).

  FIG. 4 is a configuration diagram of the second embodiment of the present invention. Components similar to those in FIG. 1 are denoted by the same or similar reference numerals.

  In the present embodiment, the air motor 5A is used as the motor means. The air motor 5A is attached to the upper end portion of the support leg 4A having a sufficient height, and above the water surface in the water tank 2 together with the rotary joint 7. It arrange | positions so that it may be located in.

  However, if the air motor 5A and the rotary joint 7 are arranged above the water surface in this way, the length of the air supply pipe 8 must be considerably increased, so that the disk member 9 of the air supply pipe 8 is slightly above. The position is supported by the steadying mechanism 13, and the steadying mechanism 13 is attached to an attachment member 14 provided in the lower part of the support leg 4A.

  In the first embodiment of FIG. 1, the submersible motor 5 is used as the motor means that is expensive and requires frequent maintenance (especially when the water 3 is severely contaminated). Then, since it is set as the structure using the air motor 5A, it becomes advantageous in price, and it becomes unnecessary to perform maintenance so frequently.

  5A and 5B are explanatory views of a third embodiment of the present invention, in which FIG. 5A is an overall configuration diagram, and FIG. 5B is a view taken along the line B-B in FIG.

  As shown in FIG. 5 (a), in this embodiment, the disk member 9 and the underwater motor 5 as the motor means are arranged in a vertically placed state in which the disk member 9 is located on the upper side, and a large number of bubble injection holes are provided. The formed board surface is a board surface on the upper surface side opposite to the lower surface side facing the submersible motor 5, and further, a minute surface that suppresses the aggregation of the microbubbles 12 above the board surface on which a large number of bubble injection holes are formed. A bubble aggregation suppressing member 15 is provided.

  As shown in FIG. 5B, the microbubble aggregation suppressing member 15 is a member having a substantially cross-sectional shape.

  A large number of microbubbles 12 peeled from the bubble injection hole 9b gradually rise in the water 3 toward the surface of the water. Grows into larger bubbles.

  Therefore, in the present embodiment, the microbubble aggregation suppressing member 15 for suppressing the aggregation of the microbubbles 12 is disposed above the disk member 9, and the plurality of microbubbles 12 are aggregated and come into contact with each other. Thus, the generation of large bubbles is prevented as much as possible.

  6A and 6B are explanatory views of a fourth embodiment of the present invention, in which FIG. 6A is a configuration diagram of a main part, and FIG. 6B is a view taken along the line BB in FIG.

  As shown in FIG. 6A, in the present embodiment, the disk member 9 is disposed between the upper surface side disk surface of the disk member 9 and the submersible motor 5 (specifically, between the rotary joint 7) in the configuration of FIG. A diffusion blade mounting plate 17 that rotates together with this is disposed. A plurality of diffusion blade members 16 are attached to the diffusion blade attachment plate 17 so as to induce the flow of water in the arrow direction from the center side of the disk member 9 to the outside.

  As shown in FIG. 6B, the diffusion blade member 16 is formed in a substantially crescent shape, and when the diffusion blade attachment plate 17 is rotated in the clockwise direction together with the disk member 9, the diffusion blade member 16 moves in the direction from the center side toward the outside. A water flow is induced. Thereby, peeling of the microbubble 12 from the bubble injection hole 9b can be promoted.

  The diffusion blade member 16 may be formed by using a thin plate steel plate for the diffusion blade mounting plate 17 and cutting a part of the steel plate, or the diffusion blade member 16 may be a resin member or the like. May be separately manufactured and attached to the diffusion blade attachment plate 17 with a screw member or the like.

  FIG. 7 is a main part configuration diagram of the fifth embodiment of the present invention. In the present embodiment, a plurality of (for example, four) support rods 19 are interposed between the upper surface side surface of the disk member 9 and the underwater motor 5 in the configuration of FIG. The disc-shaped vortex suppressing plate 18 supported by the underwater motor 5 is disposed. The vortex suppressing plate 18 is disposed so as to be separated from the disk surface of the disk member 9 by a predetermined distance L (for example, 5 cm), and remains fixed even when the disk member 9 rotates.

  In the configuration of FIG. 1, when the distance between the disk member 9 and the water surface is not so large, when the disk member 9 rotates, a vortex is generated and air on the water surface may be taken in. However, according to the configuration of the present embodiment, the generation of such vortices can be suppressed by the function of the vortex suppression plate 18.

  In addition, when the distance L is small to some extent as in this embodiment, the flow of water is induced in the direction from the center side of the disk member 9 to the outside, as in the fourth embodiment of FIG. Moreover, the effect that peeling of the microbubbles 12 from the bubble injection hole 9b is promoted can also be expected.

  FIG. 8 is a configuration diagram of the sixth embodiment of the present invention. In the present embodiment, the disk member 9 and the submersible motor 5 are disposed in a horizontal position using the horizontal support legs 4B, and the disk surface of the disk member 9 in which a number of bubble injection holes 9b are formed is A board surface opposite to the side board surface facing the motor 5 is used.

  In each of the embodiments so far, the disk member and the motor means are arranged in a vertically placed state. Therefore, when the distance between the disk member and the water surface is short, a vortex is likely to occur and air on the water surface is taken in. There was a risk of it. However, such a vortex can be made difficult to occur by setting the disk member 9 in the horizontal orientation as in the present embodiment. That is, this embodiment is effective when the state where the water surface in the water tank 2 becomes shallow occurs.

  FIG. 9 is a configuration diagram of the seventh embodiment of the present invention. In the present embodiment, in the configuration of FIG. 8, the vortex yarn attaching plate 20 is fixed at a position facing the disk surface of the disk member 9 in which a large number of bubble injection holes 9 b are formed, and is generated while the disk member 9 is rotating. One end side of the vortex 21 is attached to the vortex attachment plate 20.

  As in the sixth embodiment of FIG. 8, when the disk member 9 is in a horizontal orientation, vortices are less likely to be generated even when the water surface becomes shallow, but sometimes even a small vortex (a tornado is made smaller). May occur from the surface of the rotating disk member 9. If such generation of the vortex is left as it is, one end side of the vortex will eventually reach the water surface, and air on the water surface will be taken into the disk member 9 side.

  Therefore, in this embodiment, the vortex adhering plate 20 is fixed to the disk surface facing position of the disk member 9, and one end side of the vortex 21 is attached to the vortex adhering plate 20, so that one end side of the vortex 21 is It tries to prevent going to the water surface.

  10A and 10B are explanatory views of an eighth embodiment of the present invention, in which FIG. 10A is a configuration diagram of the main part, and FIG. 10B is a view taken along the line BB in FIG.

  As shown in FIG. 10A, in the present embodiment, one end side of the support member 22 is attached to the lower end side of the submersible motor 5 in the configuration of FIG. 1, and the attachment member 23 is attached to the other end side. A sliding contact member 24 slidable while being in contact with the disc surface of the disc member 9 is attached to the disc 23. The lower end portion of the sliding contact member 24 serves as a contact portion with respect to the disk surface of the disk member 9, but the degree of this contact is of course a light contact that does not hinder the smooth rotation of the disk member 9. In addition, although the material of the sliding contact member 24 is not specifically limited, In this embodiment, a soft resin plate member or a soft resin brush member is assumed.

  Also, as shown in FIG. 10B, the width of the sliding contact member 24 is substantially the same as the width of the setting region R, and two are disposed on the setting region R at intervals of 180 degrees. Therefore, when the disk member 9 is rotated halfway, the upper ends of all the bubble injection holes 9 b are wiped (wiped) by the sliding contact member 24. Thus, by arranging the sliding contact member 24 on the disk surface of the disk member 9, it is possible to obtain microbubbles having a smaller diameter, and to remove various pollutants and the like that block the bubble injection hole 9b. You can obtain the effect of two birds with one stone, which is possible (cleaning effect).

  Here, the reason why microbubbles having a smaller diameter can be obtained by arranging the sliding contact member 24 will be described with reference to the explanatory view of FIG.

  First, as shown in FIG. 11A, considering the case where there is no sliding contact member, the microbubbles 12 in the state where the face is exposed from the bubble injection hole 9b are peeled off from the board surface by the shearing force. Since it grows to some extent, the microbubbles 12 in this case have a large diameter.

  However, as shown in FIG. 11B, in the case where the sliding contact member 24 is provided, the microbubbles 12 in the state where the face is exposed from the bubble injection hole 9b are in contact with the sliding contact member 24 before they grow greatly. Since the bumps are peeled off and separated from the surface, the microbubbles 12 having a small diameter can be obtained.

  In addition, in FIG.10 (b), although the example in which the two sliding contact members 24 were arrange | positioned by the 180 degree space | interval was shown, the number of this sliding contact members 24 is not specifically limited. For example, if the number of arrangements is increased such that three sliding contact members 24 are spaced by 120 degrees or four sliding contact members 24 are spaced by 90 degrees, the diameter of the microbubbles 12 can be further reduced. I can expect. Or conversely, the structure which reduces the sliding contact member 24 to one is also considered. In this case, the diameter of the microbubbles 12 is larger than in the case of two, but still a sufficient effect can be obtained as compared with the case where the sliding contact member 24 is not provided.

FIG. 1 is a configuration diagram of a first embodiment of the present invention. It is explanatory drawing which shows the structure of the disk member 9 in FIG. 1, (a) is a longitudinal cross-sectional view of the disk member 9 and the air supply pipe 8, (b) is a BB arrow line view of (a). It is explanatory drawing about changing the shape of the bubble injection hole 9b in 1st Embodiment, (a) is sectional drawing for demonstrating the relationship between the shear force F and the adhesive force Fb, (b) is bubble injection. The top view at the time of making hole 9b circular, (c) is the top view at the time of making bubble injection hole 9b square. The block diagram of the 2nd Embodiment of this invention. It is explanatory drawing of the 3rd Embodiment of this invention, (a) is a whole block diagram, (b) is a BB arrow line view of (a). It is explanatory drawing of the 4th Embodiment of this invention, (a) is a block diagram of the principal part, (b) is a BB arrow line view of (a). The principal part block diagram of the 5th Embodiment of this invention. The block diagram of the 6th Embodiment of this invention. The block diagram of the 7th Embodiment of this invention. It is explanatory drawing of the 8th Embodiment of this invention, (a) is a block diagram of the principal part, (b) is a BB arrow line view of (a). It is explanatory drawing about the effect of the sliding contact member 24 in 8th Embodiment, (a) shows the case where a sliding contact member is provided, (b) shows the case where a sliding contact member is provided.

Explanation of symbols

1: Floor 2: Water tank 3: Water 4, 4A, 4B: Support legs 5, 5A: Underwater motor 6: Rotating shaft 7: Rotary joint 8: Air supply pipe 9: Disk member 9a: Cavity 9b: Bubble injection hole 10 : Air supply line 11: Blower 12: Microbubble 13: Stabilizing mechanism 14: Mounting member 15: Microbubble aggregation suppressing member 16: Diffusion blade member 17: Diffusion blade mounting plate 18: Vortex suppression plate 19: Support rod 20: Vortex Thread adhering plate 21: Vortex yarn 22: Support member 23: Mounting member 24: Sliding member
R: Setting area

Claims (1)

A disk member that is disposed in the water to be injected with microbubbles, has a cavity formed therein, and has a plurality of bubble injection holes formed on the disk surface, and an air supply line for the cavity of the disk member Air supply means for supplying air through, and motor means for rotationally driving the disk member, and a large number of bubble injection holes formed on the disk surface of the disk member include bubbles when the disk member rotates. In the microbubble generator formed in the setting region where the peripheral speed of the injection hole is equal to or higher than a predetermined speed,
The disk member and the motor means are disposed in a vertically placed state with the disk member positioned on the lower side, and the disk surface on which the plurality of bubble injection holes are formed is disposed on the upper surface of the disk surface facing the motor means. And
A micro-bubble generating device comprising a sliding contact member disposed in a bubble injection hole of the disk member so as to slide in contact with the disk surface of the set area in the water .

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