JP2009112975A - Fine bubble generator and fine bubble generating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fine bubble generator generating fine bubbles and a fine bubble generating method generating fine bubbles. <P>SOLUTION: The fine bubble generator is provided with an ejector type bubble generating nozzle having a liquid introducing part, a gas introducing part, a discharge hole for bubble-containing liquid, and an impingement plate connected to the nozzle. The impingement plate is disposed at a location where the bubbles in the bubble-containing liquid discharged from the discharge hole impinge. In the fine bubble generating method, liquid is introduced into the liquid introducing part, and gas is introduced into the gas introducing part, then the bubble-containing liquid is discharged from the discharge hole, and the bubbles in the bubble-containing liquid are made to impinge against the impingement plate. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a device for generating fine bubbles (a fine bubble generator) and a method for generating fine bubbles (a method for generating fine bubbles).

  Bubbles with a small bubble diameter have high solubility in liquids. For example, water containing oxygen bubbles is used for purifying rivers and the like. As an apparatus for generating such bubbles, International Patent Publication No. 01/036105 pamphlet (Patent Document 1) discloses bubble generation employing a so-called ejector system having a liquid introduction part, a gas introduction part, and a discharge hole for a bubble-containing liquid. Nozzles (hereinafter sometimes referred to as ejector-type bubble generating nozzles) are described.

International Patent No. 01/036105 Pamphlet

  However, when bubbles are generated using the nozzle, that is, when liquid is introduced into the liquid introduction portion of the nozzle and gas is introduced into the gas introduction portion of the nozzle to generate bubbles, a unit of liquid is used. The introduction volume per hour (hereinafter sometimes referred to as liquid introduction rate) must be very large relative to the introduction volume per unit time of gas (hereinafter also referred to as gas introduction rate). In other words, bubbles having a small bubble diameter could not be generated.

  Accordingly, an object of the present invention is to provide an apparatus capable of generating bubbles having a small bubble diameter, that is, fine bubbles, without increasing the introduction rate of the liquid so much as compared with the introduction rate of the gas.

  As a result of intensive studies, the inventors of the present invention are provided with the ejector-type bubble generating nozzle and a collision plate connected to the nozzle, and the collision plate has a bubble in the bubble-containing liquid discharged from the discharge hole. It has been found that the above object can be achieved by the device provided at the collision position, and the present invention has been completed.

  That is, the present invention includes an ejector-type bubble generating nozzle having a liquid introduction portion, a gas introduction portion, and a bubble-containing liquid discharge hole, and a collision plate connected to the nozzle, and the collision plate extends from the discharge hole. The present invention provides a fine bubble generating device provided at a position where bubbles in a bubble-containing liquid to be discharged collide.

  Further, the present invention introduces a liquid into the liquid introduction portion, introduces a gas into the gas introduction portion, and then discharges a bubble-containing liquid from the discharge hole, and then causes the bubbles in the bubble-containing liquid to flow into the collision plate It is intended to provide a method for generating fine bubbles, which is characterized in that the microbubbles are caused to collide.

  According to the present invention, it is possible to generate a bubble having a small bubble diameter, that is, a fine bubble without increasing the introduction rate of the liquid as much as the introduction rate of the gas.

  Hereinafter, the present invention will be described in detail with reference to FIGS. FIG. 1 is a side view illustrating a fine bubble generator of the present invention, and FIG. 2 is a side view illustrating a use state of the fine bubble generator of the present invention. These are schematically shown, and the present invention is not limited to these.

  As shown in FIG. 1, the fine bubble generating device of the present invention includes an ejector type bubble generating nozzle 1 and a collision plate 7 connected to the nozzle 1. The ejector-type bubble generating nozzle 1 referred to here may have a liquid introducing portion 2, a gas introducing portion 3, and a discharge hole 4 for the bubble-containing liquid. Examples of the ejector-type bubble generating nozzle 1 include those commonly used, and examples thereof include “O-MAX type-I type, ejector type” manufactured by Auratech.

  The liquid introduction part 2 is an introduction hole for introducing a liquid into the ejector-type bubble generating nozzle 1. Usually, a liquid introduction pipe 5 is attached to the liquid introduction part 2, and the liquid is introduced through the pipe 5. . The gas introduction part 3 is an introduction hole for introducing a gas into the ejector-type bubble generating nozzle 1. Usually, a gas introduction pipe 6 is attached to the gas introduction part 3, and the gas is introduced through the pipe 6. .

  When the liquid and the gas are introduced into the ejector-type bubble generation nozzle 1, the liquid and the gas are mixed in the nozzle 1, and bubbles are generated in the liquid. Thereafter, a liquid containing bubbles (bubble-containing liquid) is discharged from the discharge holes 4.

  In the fine bubble generation device of the present invention, when the bubble-containing liquid is discharged from the discharge hole 4 of the ejector-type bubble generation nozzle 1 as described above, the collision plate 7 is provided at a position where the bubbles in the bubble-containing liquid collide. It is characterized by. By providing the collision plate 7 at such a position, it is possible to effectively generate bubbles having a small bubble diameter, that is, fine bubbles, without increasing the liquid introduction speed so much as compared with the gas introduction speed. Can do. As described above, the collision plate 7 only needs to be provided at a position where the bubbles in the bubble-containing liquid discharged from the discharge hole 4 collide, and the collision plate 7 also has a direction in which the bubbles collide with the collision plate 7. Any orientation is acceptable. Preferably, the orientation is perpendicular to the discharge direction of the bubble-containing liquid. Further, the distance between the discharge hole 4 and the collision plate 7 may be such a distance that bubbles collide with the collision plate 7. Depending on the size of the ejector type bubble generating nozzle 1, for example, when “O-MAX type-I type, ejector type” manufactured by Auratech is used as the nozzle 1, it collides with the discharge hole 4. The distance from the plate 7 is preferably about 3 to 50 mm, and more preferably about 3 to 20 mm.

  Further, the size of the collision plate 7 may be any size as long as bubbles collide with the collision plate 7. The collision plate 7 may be made of any material that is inert to the liquid or gas introduced. Examples of the collision plate 7 include a metal plate and a plate whose surface is lined with fluororesin or glass. Etc. can be used.

  The ejector type bubble generating nozzle 1 and the collision plate 7 are usually connected via a connecting member 8. Since a load is generated when bubbles collide with the collision plate 7, the nozzle 1 and the connection member 8, and the connection member 8 and the collision plate 7 are joined to withstand the load.

  The connection position of the ejector type bubble generating nozzle 1 and the connection member 8 is not particularly limited as long as it is a connectable position. The connection position between the collision plate 7 and the connecting member 8 is not particularly limited, but is preferably connected to the end of the collision plate 7. Further, the number of connecting members 8 is not particularly limited, but is preferably a plurality from the viewpoint of withstanding the load.

  Next, the usage method of the microbubble generator of this invention is demonstrated. First, as described above, the liquid is introduced into the liquid introduction part 2 through the liquid introduction pipe 5, and the gas is introduced into the gas introduction part 3 through the gas introduction pipe 6. Such liquid may be introduced from the outside, or as shown in FIG. 2, the liquid 13 previously filled in the container 14 is circulated by a circulation pump 11 provided in the middle of the liquid introduction pipe 5. The liquid may be introduced into the liquid introduction unit 2. In this case, by adjusting the output of the circulation pump 11, the circulation rate and introduction rate of the liquid can be adjusted.

  The gas is usually introduced from the outside. In addition, as shown in FIG. 2, a gas flow rate can be controlled by providing a mass flow controller in the middle of the gas introduction pipe 6 and adjusting the mass flow controller.

  Examples of the liquid include organic compounds such as alcohols such as methanol and ethanol, ethers such as diethyl ether and tetrahydrofuran, aliphatic hydrocarbons such as hexane and cyclohexane, aromatic hydrocarbons such as benzene and toluene, and water. In the present invention, an organic compound is particularly preferably used.

  Examples of the gas include air, oxygen, nitrogen, hydrogen, helium, ozone, and chlorine.

  The introduction volume per unit time of the liquid, that is, the introduction speed of the liquid, and the introduction volume per unit time of the gas, that is, the introduction speed of the gas can be selected as appropriate. It is preferable that the ratio of the introduction speeds is 1-50. In the present invention, even when the liquid introduction speed is not so large as compared with the gas introduction speed, the bubbles generated from the ejector-type bubble generation nozzle 1 are made to collide with the collision plate 7, thereby making the finer. Bubbles can be generated. In addition, by reducing the liquid introduction speed, the pressure loss in the nozzle 1 can be suppressed, and the energy loss resulting from the pressure loss can also be suppressed. The fine bubble generator of the present invention is advantageous in this respect.

  The size of the bubbles generated by the fine bubble generator of the present invention may vary depending on the liquid introduction speed or the gas introduction speed, but is usually about 0.10 mm to 0.60 mm.

  The fine bubbles generated as described above are useful for river cleaning, oxidation reaction or reduction reaction using gas as a raw material, and the fine bubble generator of the present invention can be applied to such fields. is there.

  Examples of the present invention will be described below, but the present invention is not limited thereto. The bubble diameter was obtained by image-analyzing an image obtained by photographing bubbles with a high-speed camera (REDDLAKE, MotionScope Mi) using image analysis software (Media Cybernetics, Image-Pro PLUS Ver6). The average bubble size was calculated from the obtained bubble size distribution.

Example 1
It implemented by the apparatus as shown in FIG. First, the liquid introduction pipe 5 was attached to the liquid introduction part 2, and the gas introduction pipe 6 was attached to the gas introduction part 3. Next, in a container 14 (3 L glass beaker) in which 2.5 L of cyclohexane has been put in advance, an ejector type bubble generating nozzle 1 (“O-MAX type-I type, ejector type” manufactured by Aura Tech), The connecting member 8 and the collision plate 7 (made of tetrafluoroethylene, 5 cm long and 5 cm wide) were put so as to be immersed in cyclohexane. The liquid inlet 12 was also placed so as to be immersed in cyclohexane. At this time, the distance between the discharge hole 4 and the collision plate 7 was 5 mm. Thereafter, cyclohexane was circulated at a rate of 1 L / min by the circulation pump 11 and introduced into the nozzle 1. On the other hand, nitrogen was supplied to the gas supply port 10 and the mass flow controller 9 was adjusted to introduce nitrogen into the nozzle 1 at a nitrogen introduction rate of 50 ml / min. The ratio of the liquid introduction speed to the gas introduction speed at this time was 20. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 0.412 mm.

Example 2
Air bubbles were generated in the same manner as in Example 1 except that nitrogen was introduced at a rate of 100 ml / min. The ratio of the liquid introduction speed to the gas introduction speed at this time was 10. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 0.437 mm.

Example 3
Air bubbles were generated in the same manner as in Example 1 except that the introduction rate of nitrogen was set at 200 ml / min. The ratio of the liquid introduction speed to the gas introduction speed at this time was 5. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 0.431 mm.

Example 4
Air bubbles were generated in the same manner as in Example 1 except that the nitrogen introduction rate was 500 ml / min. The ratio of the liquid introduction speed to the gas introduction speed at this time was 2. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 0.525 mm.

Example 5
Air bubbles were generated in the same manner as in Example 1 except that cyclohexane was circulated at 1.5 L / min. At this time, the ratio of the liquid introduction speed to the gas introduction speed was 30. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 0.434 mm.

Example 6
Bubbles were generated in the same manner as in Example 1 except that cyclohexane was circulated at 1.5 L / min and the nitrogen introduction rate was 100 ml / min. At this time, the ratio of the liquid introduction speed to the gas introduction speed was 15. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 0.439 mm.

Example 7
Bubbles were generated in the same manner as in Example 1 except that cyclohexane was circulated at 1.5 L / min and the nitrogen introduction rate was 200 ml / min. At this time, the ratio of the liquid introduction speed to the gas introduction speed was 7.5. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 0.521 mm.

Example 8
Air bubbles were generated in the same manner as in Example 1 except that cyclohexane was circulated at 2.0 L / min. The ratio of the liquid introduction speed to the gas introduction speed at this time was 40. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 0.424 mm.

Example 9
Bubbles were generated in the same manner as in Example 1 except that cyclohexane was circulated at 2.0 L / min and the nitrogen introduction rate was 100 ml / min. The ratio of the liquid introduction speed to the gas introduction speed at this time was 20. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 0.446 mm.

Example 10
Bubbles were generated in the same manner as in Example 1 except that cyclohexane was circulated at 2.0 L / min and the nitrogen introduction rate was 200 ml / min. The ratio of the liquid introduction speed to the gas introduction speed at this time was 10. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 0.472 mm.

Example 11
Bubbles were generated in the same manner as in Example 1 except that cyclohexane was circulated at 2.0 L / min and the nitrogen introduction rate was 500 ml / min. The ratio of the liquid introduction speed to the gas introduction speed at this time was 4. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 0.469 mm.

Comparative Example 1
The same operation as in Example 1 was performed except that the collision plate 7 was not used. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 0.617 mm.

Comparative Example 2
The same operation as in Example 2 was performed except that the collision plate 7 was not used. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 0.712 mm.

Comparative Example 3
The same operation as in Example 3 was performed except that the collision plate 7 was not used. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 0.853 mm.

Comparative Example 4
The same operation as in Example 4 was performed except that the collision plate 7 was not used. When the bubbles generated in cyclohexane were analyzed, the average bubble diameter was 1.017 mm.

It is a side view which illustrates the fine bubble generator of this invention. It is a side view which illustrates the use condition of the microbubble generator of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ejector type bubble generation nozzle 2 Liquid introduction part 3 Gas introduction part 4 Bubble-containing liquid discharge hole 5 Liquid introduction pipe 6 Gas introduction pipe 7 Collision plate 8 Connecting member 9 Mass flow controller 10 Gas supply port 11 Circulation pump 12 Liquid suction Mouth 13 Liquid 14 Container

Claims (4)

An ejector-type bubble generating nozzle having a liquid introducing portion, a gas introducing portion, and a bubble-containing liquid discharge hole;
A collision plate connected to the nozzle,
The fine bubble generating device, wherein the collision plate is provided at a position where bubbles in the bubble-containing liquid discharged from the discharge holes collide.   A liquid is introduced into the liquid introduction part according to claim 1, and after introducing the gas into the gas introduction part according to claim 1, the bubble-containing liquid is discharged from the discharge hole according to claim 1, and then the bubble-containing liquid A method for generating fine bubbles, wherein the bubbles are caused to collide with the collision plate according to claim 1.   The ratio of the introduction volume per unit time of the liquid introduced into the liquid introduction unit to the introduction volume per unit time of the gas introduced into the gas introduction unit is 1 to 50. Method.   The method for generating fine bubbles according to claim 2 or 3, wherein the liquid is an organic compound.

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