JP2009160530A - Nano bubble generating nozzle and nano bubble generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nozzle with a compact configuration capable of conveniently generating nano bubbles and a nano bubble generator using the same. <P>SOLUTION: The nozzle 34 that is cylindrically provided where a channel 42 is formed inside and generates nano bubbles in a liquid, wherein an inflow port 45 that allows a liquid to flow in is formed at one end in the axial direction, an outflow port 47 that allows the liquid in which the nano bubbles are mixed to flow out is formed at the other end in the axial direction, the same diameter section 44 having the same diameter as in the predetermined distance from the port 45 and a tapered section 46 whose diameter is gradually widened towards the port 47 from the section 44 are formed in the channel 42, and a gas introducing hole 50 that introduces a gas into the channel 42 is formed so as to be in communication with the section 44 and outside. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a nozzle for generating nanobubbles in a liquid and a nanobubble generator using the nozzle.

  An apparatus for generating microbubbles in water has been conventionally developed, and purification of water quality and the like are expected with microbubbles (see, for example, Patent Document 1).

On the other hand, research on nanobubbles having a smaller bubble diameter than microbubbles has been started. Research results indicate that nanobubbles have better water purification and bactericidal properties than microbubbles, and are expected to have a positive effect on the human body.
In general, the bubble diameter is defined as 10 to 200 μm as microbubbles, 0.5 to 10 μm as micronano bubbles, and 0.5 μm or less as nanobubbles. In the present specification, nanobubbles refer to those having a diameter of 0.5 μm or less.

Various methods for generating nanobubbles have been proposed.
For example, a method has been proposed in which a part of a liquid is gasified and nanobubbles are generated by irradiating this with ultrasonic waves (see, for example, Patent Document 2).
In addition, there is a method in which microbubbles having a diameter larger than that of nanobubbles are generated, and nanobubbles are generated by applying a physical impact to the bubbles (see, for example, Patent Document 3 and Patent Document 4).
There has also been proposed a method of generating a nanofluid containing nanobubbles by mixing a gas and a liquid in a gas-liquid mixing chamber and then discharging them from an ultra-fine discharge port (see, for example, Patent Document 5).

JP-A-2005-305219 JP 2003-334548 A JP 2005-245817 A JP 2006-289183 A JP 2007-90156 A

According to the nanobubble generator as shown in Patent Document 2 to Patent Document 5 described above, a very large device is required. For this reason, there is a problem that, regardless of the size of the device itself, it is difficult for the conventional nanobubble generator to be widely used in general households in terms of cost.
In addition, due to the large-scale equipment, it was not easy to install and operate, and there was a problem that research on the effects of nanobubbles would not be conducted.

  Accordingly, the present invention has been made to solve the above problems, and an object thereof is to provide a nozzle capable of easily generating nanobubbles with a compact configuration and a nanobubble generating apparatus using the nozzle.

In order to achieve the above object, the present invention comprises the following arrangement. That is, according to the nanobubble generating nozzle according to the present invention, the nozzle is provided in a cylindrical shape having a flow path formed therein, and generates a nanobubble in the liquid, and is provided at one end in the axial direction. An inflow port for inflowing liquid is formed, and an outflow port for outflowing the liquid mixed with nanobubbles is formed at the other end in the axial direction, and the flow path has the same diameter at a predetermined distance from the inflow port. The same diameter portion and a tapered portion that gradually increases in diameter from the same diameter portion toward the outlet are formed, and a gas introduction hole that introduces gas into the flow path communicates the same diameter portion and the outside. It is characterized by being formed as follows.
By adopting this configuration, nano bubbles can be generated with a very compact configuration.

The taper angle of the tapered portion may be between 3 ° and 5 °.
Furthermore, the taper angle of the taper portion may be between 3.5 ° and 4.5 °.
The taper angle of the taper portion may be 4 °.

According to the nanobubble generator concerning this invention, it comprises the nozzle for nanobubble generation of any one of Claims 1-4, and the pump which sends a liquid into this nozzle for nanobubble generation, It is characterized by the above-mentioned. It is said.
According to this configuration, nanobubbles can be generated with a very compact configuration.
The pump may be a submersible pump.

  According to the nanobubble generating nozzle and the nanobubble generating apparatus of the present invention, nanobubbles can be generated without clogging with a compact configuration. For this reason, a nanobubble generator can be provided as an inexpensive apparatus.

Hereinafter, preferred embodiments of a nanobubble generator according to the present invention will be described in detail with reference to the accompanying drawings.
(First embodiment)
FIG. 1 is an explanatory diagram showing the overall configuration of the nanobubble generator of this embodiment.
The nanobubble generator 30 includes a submersible pump 32, a nozzle 34, and a hose 36 that connects the submersible pump 32 and the nozzle 34. Then, nanobubbles are discharged together with water from the outlet 47 of the nozzle 34.

  An air tube 38 for supplying gas is connected to the nozzle 34. A speed controller 40 is connected to the tip of the air tube 38. By adjusting the speed controller 40, the flow rate of the gas supplied to the nozzle 34 can be controlled.

The submersible pump 32 has a built-in DC motor and is driven by a direct current. For this reason, the submersible pump 32 includes a connection plug 31 for a household power supply AC 100V and a converter 33 that converts the taken alternating current into a direct current.
By driving the submersible pump 32 with a DC motor, the overall size can be reduced and the cost can be reduced.

Next, the structure of the nozzle 34 will be described with reference to FIG.
The nozzle 34 mixes the gas introduced from the air tube 38 and the liquid fed from the submersible pump 32 to generate nanobubbles in the liquid. The nozzle 34 is formed in a cylindrical shape as a whole, and an inlet 45 for feeding water into the inside is formed at one end in the axial direction of the cylinder, and a water inlet is formed at the other end in the axial direction of the cylinder. Is formed.
The inflow port 45 and the outflow port 47 communicate with each other through a flow path 42 that penetrates the inside in the axial direction.
The material of the nozzle 34 is not particularly limited as long as it is a material that is not deformed or deteriorated, but a metal or a synthetic resin can be used.

The flow path 42 includes an identical diameter portion 44 having a constant diameter and a tapered portion 46 that gradually increases in diameter in the outflow direction.
Further, the connection portion 48 to which the air tube 38 is connected is provided at a portion where air is supplied to the same diameter portion 44. The connection portion 48 is formed by drilling a hole having a diameter enough to insert the end of the air tube 38 in the outer wall surface of the nozzle 34.
A communication hole 50 communicating with the same diameter portion 44 of the flow path 42 is formed on the bottom surface of the connection portion 48. The communication hole 50 is formed in a direction orthogonal to the same diameter portion 44 of the flow path 42.

  In addition, the outer wall part of the edge part of the one side of the nozzle 34 is formed in the shape which can connect the hose 36. FIG. That is, the outer diameter of the one end portion of the nozzle 34 is substantially the same as the inner diameter of the hose 36 so that the hose 36 can be inserted into the one end portion of the nozzle 34. In the present embodiment, the outer wall portion at one end of the nozzle 34 has a tapered shape that gradually decreases toward the hose 36, and is provided so as to be easily connected to the hose 36.

Hereinafter, specific shapes of the flow path and the communication hole will be described.
As a result of various experiments, it was confirmed that nanobubbles were easily generated by using a nozzle having a shape as described below.
First, the feature is that the flow path 42 of the nozzle 34 is formed in a tapered shape so that the diameter gradually increases in the liquid discharge direction (outlet 47 direction). Here, the taper angle θ is preferably between 3 ° and 5 °.
Particularly preferably, the taper angle θ is between 3.5 ° and 4.5 °.
Most preferably, the taper angle θ is 4 °.

  Moreover, it is preferable that the diameter of the communicating hole 50 is 0.3 mm-0.4 mm. Particularly preferably, the communication hole 50 has a diameter of 0.3 mm.

  Moreover, it is preferable that the diameter of the inflow port part (same diameter part 44) of the flow path 42 is 3.0 mm-4.0 mm. Particularly preferably, the diameter of the inflow port portion (same diameter portion 44) is 3.5 mm.

(Second Embodiment)
In the embodiment described above, the pump that sends the liquid to the nozzle 34 is a submersible pump. However, the pump is not limited to the submersible pump, and a normal pump may be used.
An embodiment using a normal pump is shown in FIG. In addition, about the same component as 1st Embodiment mentioned above, the same code | symbol may be attached | subjected and description may be abbreviate | omitted.

  The nanobubble generator 30 includes a pump 60 installed in the atmosphere, a nozzle 34 disposed in water, a hose 36 connecting the pump 60 and the nozzle 34, and a water supply hose for supplying water to the pump 60. 62. Then, nanobubbles are discharged together with water from the outlet 47 of the nozzle 34.

The pump 60 discharges the water supplied from the water supply hose 62 to the hose 36 with a predetermined discharge amount. In this way, the water is supplied to the inlet of the nozzle 34 through the hose 36 by the pump 60.
Note that the pump 60 of this embodiment is driven by an AC motor.

  An air tube 38 for supplying gas is connected to the nozzle 34. A speed controller 40 is connected to the tip of the air tube 38. By adjusting the speed controller 40, the flow rate of the gas supplied to the nozzle 34 can be controlled. This is the same configuration as in the first embodiment.

Next, a measurement method for measuring the diameter of the generated nanobubbles will be described.
For the measurement, a fiber optical dynamic light scattering photometer (model name: FDLS3000) manufactured by Otsuka Electronics Co., Ltd. can be used.
The FDLS 3000 can analyze Stokes particle size, polydispersity index, diffusion coefficient, and attenuation constant by cumulant analysis, and can analyze scattering intensity distribution, weight conversion distribution, and number conversion distribution by histogram analysis.

FIG. 4 shows a measurement system inside the FDLS 3000.
The light source 52 of the FDLS 3000 is a fixed laser having a wavelength of 532 nm, and the output is 100 mW.
The laser light is irradiated to the sample cell 56 through an optical element group 54 such as a shutter, an ND filter, a wave plate, a lens, and a polarizing plate. The sample cell 56 is formed in a cylindrical shape, and a liquid to be measured is sealed inside.
The diameter of the sample cell 56 can be selected from 5 mm, 12 mm, 21 mm, and the like.

A light receiving element 57 is arranged around the sample cell 56. A specific example of the light receiving element 57 is a movable optical fiber connected to a cooled photomultiplier tube 58, and this optical fiber can detect the scattered light of the laser light applied to the sample cell 56. The cooled photomultiplier tube 58 can reliably detect scattered light scattered by nano-order bubbles.
A beam stopper 59 that absorbs the laser light that has passed through the sample cell 56 is disposed behind the sample cell 56 with respect to the incident direction of the laser light.

Example 1
FIG. 5 shows the result of measuring the diameter of the nanobubbles generated by the nanobubble generator 30 shown in FIG. 3 using the photometer described above.
As the pump 60, a magnet pump manufactured by Lacy Co., Ltd., model name RMD-401 was used. The specifications of this pump are a power supply of AC 100 V, power consumption of 90 W, a maximum lift of 4.6 m, and a maximum discharge amount of 45 l / min.

Moreover, the specific shape of the nozzle 34 employ | adopted by the present Example is shown in FIG.
The shape of the nozzle 34 is a total length of 100 mm, a diameter of 15 mm, a diameter of the same diameter of 3.5 mm, a taper angle of 4 ° at the taper, a total length of the taper of 80 mm, a diameter of the opening of 9.18 mm, and a diameter of the communication hole of 0.3 mm. It is.
The material of the nozzle 34 is brass.

  The solvent was water, and nanobubbles were generated in the water. The water temperature is 21.2 ° C. The refractive index of water as a solvent is 1.3317. The viscosity of water as a solvent is 0.9725 cp. The scattering intensity of water as a solvent is 8539 cps.

The graph of FIG. 5 shows the measured scattered light intensity distribution in a graph, with the horizontal axis representing the bubble diameter (nm) and the vertical axis representing the scattered light intensity distribution (ls).
As shown in the graph of FIG. 5, as a result, it was found that the average particle size of the nanobubbles generated using the nanobubble generator 30 was 270.2 nm. Thus, nanobubbles having a very small diameter could be generated satisfactorily with a simple configuration.
In this result, although there is an intensity distribution of scattered light around a particle size of 10,000 nm, this distribution is not related to nanobubbles.

(Example 2)
FIG. 7 shows another result of measuring the diameter of the nanobubbles generated by the nanobubble generator 30 having the same configuration as that of Example 1 described above with the photometer described above.
In addition, since the pump and nozzle used in Example 2 are the same as Example 1, description about a pump and a nozzle is abbreviate | omitted here.

  The solvent was water, and nanobubbles were generated in the water. The water temperature is 22.6 ° C. The refractive index of water as a solvent is 1.3315. The viscosity of water as a solvent is 0.9382 cp. The scattering intensity of water as a solvent is 6923 cps.

The graph of FIG. 7 is a graph showing the measured scattered light intensity distribution, with the horizontal axis representing the bubble diameter (nm) and the vertical axis representing the scattered light intensity distribution (ls).
As shown in the graph of FIG. 7, as a result, it was found that the average particle size of nanobubbles generated using the nanobubble generator 30 was 295.6 nm. Thus, nanobubbles having a very small diameter could be generated satisfactorily with a simple configuration.
Even in this result, there is an intensity distribution of scattered light around a particle size of 10000 nm, but this distribution has nothing to do with nanobubbles.

The nanobubble generator of the present invention can be installed in a bath in a general household due to its compact configuration. Thereby, health improvement can be aimed at in the bath at home.
In addition, water mixed with nanobubbles can be used as various washing waters.
Furthermore, it can be used for various purposes such as activation of fish bred in aquarium and hydroponics.

  The present invention has been described above with reference to preferred embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the invention. is there.

It is explanatory drawing which shows the whole structure of 1st Embodiment of the nanobubble generator concerning this invention. It is sectional drawing of the nozzle for nanobubble generation concerning this invention. It is explanatory drawing which shows the whole structure of 2nd Embodiment of a nanobubble generator. It is explanatory drawing which shows the measurement system inside a photometer. It is the graph which measured the particle size of the nano bubble generated using the nano bubble generator of FIG. It is explanatory drawing which shows the specific dimension of the nozzle used in experiment. It is the graph which measured the particle size of the nano bubble generated using the nano bubble generator of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 30 Nanobubble generator 31 Connection plug 32 Submersible pump 33 Converter 34 Nozzle 36 Hose 38 Air tube 40 Speed controller 42 Channel 44 Same diameter part 45 Inlet 46 Taper part 47 Outlet 48 Connection part 50 Communication hole 52 Light source 54 Optical element group 56 Sample cell 57 Light receiving element 58 Cooling photomultiplier tube 59 Beam stopper 60 Pump 62 Water supply hose

Claims (6)

Provided in a cylindrical shape with a flow path formed inside, a nozzle for generating nanobubbles in the liquid,
An inflow port through which liquid flows into one end in the axial direction is formed,
An outflow port for flowing out the liquid mixed with nanobubbles is formed at the other end in the axial direction,
The flow path is formed with the same diameter portion having the same diameter at a predetermined distance from the inflow port, and a taper portion gradually increasing in diameter from the same diameter portion toward the outflow port,
A nozzle for generating nanobubbles, wherein a gas introduction hole for introducing gas into the flow path is formed so as to communicate the same diameter portion and the outside.   The nanobubble generating nozzle according to claim 1, wherein a taper angle of the taper portion is between 3 ° and 5 °.   The nozzle for generating nanobubbles according to claim 2, wherein a taper angle of the taper portion is between 3.5 ° and 4.5 °.   4. The nanobubble generating nozzle according to claim 3, wherein a taper angle of the taper portion is 4 [deg.]. A nanobubble generating nozzle according to any one of claims 1 to 4,
A nanobubble generator comprising: a pump for feeding a liquid to the nanobubble generating nozzle.   6. The nanobubble generator according to claim 5, wherein the pump is a submersible pump.

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