JP7443638B2 - A nozzle for generating fine bubbles, a method for mixing bubbles containing fine bubbles into a liquid using the nozzle for generating fine bubbles, and a biological reaction device equipped with the nozzle for generating fine bubbles. - Google Patents

Description

The present invention provides a fine bubble generation nozzle used to mix ultrafine bubbles or fine bubbles of gas such as air or oxygen into a liquid to produce a liquid containing fine gas bubbles; The present invention relates to a method of mixing bubbles containing microbubbles into a liquid using this nozzle for generating microbubbles, and a biological reaction device equipped with this nozzle for generating microbubbles, and in particular, it is easy to disassemble and assemble in a short time. It features a nozzle for generating fine bubbles that can be used to easily inspect and remove deposits and foreign matter.

Focusing on the effect of the microbubbles contained in the liquid to increase the dissolved oxygen concentration (DO) of the liquid and the sterilization/sterilization effect, liquids containing microbubbles are used in shower water, bathtub water, washing water, and washing water. It is also used in the field of wastewater treatment such as wastewater generated from various industries such as food plants, pulp plants, chemical plants, domestic wastewater, etc. ) is used in the field of culturing microorganisms to produce reaction products or propagating microorganisms] and in the field of fish and shellfish aquaculture.

"Fine bubbles" in the present invention means "fine bubbles" and/or "ultra fine bubbles." ``Normal bubbles'' rise rapidly through water, burst on the surface, and disappear, whereas ``fine bubbles,'' microbubbles with a diameter of less than 100 μm, shrink in water and disappear. , along with free radicals, generate "ultra fine bubbles" which are extremely small bubbles with a diameter of less than 1 μm, and these "ultra fine bubbles" remain in water for a certain amount of time. In the present invention, as standardized by ISO (International Organization for Standardization), bubbles with a number average diameter of less than 100 μm are also referred to as "fine bubbles", and bubbles with a number average diameter of less than 1 μm are referred to as "ultra fine bubbles". Also called. Image analysis method, laser diffraction scattering method, electric sensing band method, resonance mass measurement method, optical fiber probe method, etc. are generally used to measure the bubble diameter of ultra-fine bubbles. Generally used methods include dynamic light scattering, Brownian motion tracking, electrical sensing band method, and resonance mass measurement.

A liquid containing such fine gas bubbles is produced by a plurality of jets provided on the side surface of the nozzle body along a plane perpendicular to the central axis of the nozzle body. By blowing gas through the outlet, a liquid containing microscopic gas bubbles is obtained. (Patent Documents 1 and 2)

For example, Patent Document 1 discloses a mud aeration device 110, the appearance of which is schematically shown in FIG. Mud is made to flow in through the inlet 112 and discharged from the discharge port 113, and compressed air is blown from a plurality of air outlets 114 provided on the side along a plane perpendicular to the central axis of the nozzle body 111 to remove the mud. Mixed with fine air bubbles. In this aeration device 110, as shown in the schematic diagrams in FIGS. 15 and 16, compressed air blown into the mud flowing inside the nozzle body 111 forms multiple gas bands A'. The gas flows along the inner surface of the nozzle body 111 and becomes fine bubbles B' near the discharge port 113.

However, in the fine bubble generation nozzle that blows gas from a plurality of jet ports provided on the side surface along a plane perpendicular to the central axis of the nozzle body, as disclosed in Patent Documents 1 and 2, the nozzle Since the gas blown into the liquid flowing inside the nozzle body forms multiple bands and flows along the inner surface of the nozzle body, the generation efficiency of fine bubbles is poor, making it difficult to efficiently and sufficiently control the fine bubble content of the liquid. It is difficult to improve.

Furthermore, as shown in FIG. 17, Patent Document 3 describes a first stage nozzle forming a suction zone connected to a pressurized water supply pipe 121 as an aeration device 120 that purifies various types of wastewater by blowing fine air bubbles into it. The nozzle members 123 and 124 of the bubble maturing zone consisting of one or more stages are arranged on the same axis and connected and fixed to the member 122, and a ring slit is provided at the joint position of each stage nozzle member for sucking air from the intake pipe. In addition to forming the nozzles 125 and 126 of each stage in the shape of each stage, and forming steps with different diameters so that the diameter of the passageway of the nozzle member 122, 123, 124 of each stage becomes gradually larger in each successive stage at each stage nozzle position. The equipment is described.

However, in the aeration device 120 as disclosed in Patent Document 3, the diameters of the passages of the nozzle members 122, 123, and 124 in each stage are formed with different diameter steps, so that air can be stably supplied to the inner surface of the pipe. It is not possible to form a thin layer of Furthermore, the aeration device 120 is only used for purifying various types of sewage, and cannot easily inspect and remove deposits and foreign matter, especially for sanitary products where product safety is required. It is extremely difficult to use it in production equipment lines (products such as food products, breweries, biopharmaceuticals, dairy products, chemicals, etc.).

Japanese Patent Application Publication No. 2004-121988 Japanese Patent Application Publication No. 2006-034235 Japanese Patent Application Publication No. 8-290192

The inventors of the present invention have first developed a nozzle body having a simple shape and structure made of a cylindrical body, which can improve the generation efficiency of fine bubbles and efficiently and sufficiently increase the fine bubble content of liquid. We have just filed an international application for the invention of a nozzle for generating fine bubbles. (PCT/JP2018/13730 and PCT/JP2019/14150, hereinafter also referred to as the "earlier international application")

The present invention is an improvement on the above-mentioned micro-bubble generation nozzle (hereinafter also referred to as "the above-mentioned micro-bubble generation nozzle"), and in particular, can be easily disassembled and assembled in a short time, It is characterized by the ability to easily inspect and remove deposits and foreign matter.

In other words, the object of the present invention is to improve the generation efficiency of microbubbles, to efficiently and sufficiently increase the content of microbubbles in a liquid, and to provide a simple shape and material that allows deposits and foreign matter to be easily inspected and removed. To provide a nozzle for generating fine bubbles having a structure, to provide a method for mixing bubbles containing fine bubbles into a liquid using this nozzle for generating fine bubbles, and to provide a biological reaction device equipped with this nozzle for generating fine bubbles. Our goal is to provide the following.

The inventors of the present invention have diligently studied the inspection and removal of deposits and foreign matter in the microbubble generation nozzle of the invention of the previous application, and have discovered that it is possible to easily disassemble and assemble the deposits and foreign matter in a short time. The present invention was achieved by discovering a nozzle for generating fine bubbles that can be easily inspected and removed.

The gist of the present invention is shown below.
(1) A nozzle for generating fine bubbles for mixing ultra fine bubbles or fine bubbles in a liquid to produce a liquid containing the fine bubbles,
Consisting of a nozzle main body having a cylindrical inner circumferential surface, and a gas supply section supplying gas to the inner circumferential surface of the nozzle main body,
The nozzle main body is composed of an upstream nozzle member, a downstream nozzle member, and a connecting member disposed between the nozzle members, and the three members are removably fastened by fastening means such as bolts and nuts. It is formed by attaching and fixing it,
An inlet into which liquid flows is provided on the upstream side of the upstream nozzle member,
A discharge port is provided on the downstream side of the downstream nozzle member for discharging a liquid mixed with bubbles including the microbubbles,
A slit is formed continuously on a side surface along a plane perpendicular to the central axis of the nozzle body by the downstream end of the upstream nozzle member and the upstream end of the downstream nozzle member. A nozzle for generating fine bubbles.

(2) A nozzle for generating fine bubbles for mixing ultra fine bubbles or fine bubbles in a liquid to produce a liquid containing the fine bubbles,
Consisting of a nozzle main body having a cylindrical inner circumferential surface and a gas supply section supplying gas to the inner circumferential surface of the nozzle main body,
The nozzle main body includes an upstream nozzle member, n intermediate nozzle members (n represents an integer of 2 or more), a downstream nozzle member, and a connecting member disposed between each of the plurality of nozzle members. All of the above-mentioned members are removably fastened and fixed using fastening means such as bolts and nuts,
An inlet into which liquid flows is provided on the upstream side of the upstream nozzle member,
A discharge port is provided on the downstream side of the downstream nozzle member for discharging a liquid mixed with bubbles including the microbubbles,
1) a downstream end of the upstream nozzle member and an upstream end of the intermediate nozzle member located first from the upstream side;
2) The downstream end of the intermediate nozzle member located mth from the upstream side (m represents an integer greater than or equal to n and less than n) and the upstream end of the intermediate nozzle member located (m+1)th from the upstream side. and 3) a downstream end of the n-th intermediate nozzle member from the upstream side and an upstream end of the downstream nozzle member to form a plane perpendicular to the central axis of the nozzle body. A nozzle for generating fine bubbles, characterized in that a slit is continuously formed on the side surface along the .

(3) The fine bubbles according to (1) or (2), wherein the slit has an acute angle θ inclined toward the upstream side with respect to a plane perpendicular to the central axis of the nozzle body. Generating nozzle.

(4) The fine bubble generating device according to any one of (1) to (3), wherein the inner diameter of the downstream nozzle member near the discharge port is gradually expanded toward the downstream side. nozzle.

(5) Any one of (1) to (4), characterized in that the microbubble generating nozzle is used in manufacturing equipment for sanitary products such as food, brewing, dairy, biopharmaceuticals, and chemicals. A nozzle for generating fine bubbles as described in Crab.

(6) The nozzle for generating fine bubbles according to any one of (1) to (4), characterized in that the nozzle for generating fine bubbles is used for chemical reactions.

(7) The nozzle for generating fine bubbles according to any one of (1) to (4), characterized in that the nozzle for generating fine bubbles is used for biological reactions.

(8) A method of mixing bubbles containing ultra-fine bubbles to fine bubbles into a liquid using the micro-bubble generating nozzle according to any one of (1) to (7).

(9) a culture tank containing a culture solution and a biological culture solution containing microorganisms or cells ranging from aerobic to anaerobic;
The nozzle for generating fine bubbles according to any one of (1) to (4), which causes the biological culture solution extracted from the culture tank to contain bubbles including ultra-fine bubbles or fine bubbles;
a pipe line for circulating the biological culture solution containing the microbubbles to the culture tank;
A biological reaction device comprising:

(10) The amount of biological culture fluid that is extracted from the culture tank and returned to the culture tank after containing bubbles containing microbubbles of ultra-fine bubbles or fine bubbles is calculated per minute by the amount of biological culture fluid contained in the culture tank. The biological reaction device according to (9), characterized in that the amount is set to 1% or more and less than 80% of the amount of the biological culture solution.

The microbubble generation nozzle of the present invention has a simple shape and structure, improves the efficiency of microbubble generation, and can efficiently and sufficiently increase the microbubble content of the liquid, as well as shorten disassembly and assembly. It can be easily done in a short amount of time and allows you to easily inspect and remove deposits and foreign matter.

In addition, the method of mixing bubbles containing microbubbles into a liquid using the nozzle for generating microbubbles of the present invention is simple and economical, and allows the content of microbubbles to be sufficiently increased efficiently to add microbubbles to the liquid. In addition to being able to mix the air bubbles contained in the microbubble generating nozzle, it is possible to easily inspect and remove deposits and foreign matter on the microbubble generating nozzle, thereby preventing a drop in efficiency.

In addition, the biological reaction device equipped with the nozzle for generating microbubbles of the present invention can easily and economically increase the content of microbubbles efficiently and sufficiently, and mix bubbles containing microbubbles into a liquid. , it is possible to easily inspect and remove deposits and foreign matter on the microbubble generation nozzle, prevent a drop in efficiency, reduce stress and damage to microorganisms, etc., and perform biological reactions efficiently and economically. .

BRIEF DESCRIPTION OF THE DRAWINGS It is a cross-sectional schematic diagram which shows the state before assembly of the nozzle for microbubble generation of 1st Embodiment of this invention. FIG. 2 is a schematic cross-sectional view showing the state of FIG. 1 after assembly. FIG. 2 is a schematic external view showing bolts and nuts that are an example of fastening means used for assembling the microbubble generating nozzle of the present invention. It is a cross-sectional schematic diagram which shows the state before assembly of the micro bubble generation nozzle of 2nd Embodiment of this invention. FIG. 5 is a schematic cross-sectional view showing a state after the assembly shown in FIG. 4; FIG. 1 is a schematic diagram of a culturing device for microorganisms, etc., showing an application example of the microbubble generation nozzle of the present invention. FIG. 2 is a schematic diagram showing the appearance of the first embodiment of the fine bubble generation nozzle. It is a schematic diagram showing the cross section of a 1st embodiment of the above-mentioned fine bubble generation nozzle. 9 is a schematic diagram showing a cross section taken along line II in FIG. 8. FIG. FIG. 8 is a schematic diagram showing the appearance of the fine bubble generation nozzle of FIG. 7 provided with a gas supply section. It is a schematic diagram which shows the cross section of 2nd Embodiment of the above-mentioned nozzle for generating fine bubbles. It is a schematic diagram which shows the cross section of 3rd Embodiment of the above-mentioned nozzle for generating fine bubbles. It is a schematic diagram which shows the cross section of 4th Embodiment of the above-mentioned nozzle for generating fine bubbles. FIG. 2 is a schematic diagram showing the appearance of the microbubble generating nozzle of Patent Document 1. FIG. 2 is a schematic diagram showing a cross section of a nozzle for generating fine bubbles of Patent Document 1. 16 is a schematic diagram showing a cross section taken along line II-II in FIG. 15. FIG. It is a partial cross-sectional schematic diagram of the aeration device of patent document 3.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, but the present invention is not limited thereto.

1. First, the nozzle for generating fine bubbles , which is the basis of the nozzle for generating fine bubbles of the present invention, will be explained.

<Nozzle for generating fine bubbles>
As shown in FIGS. 7 to 9, the microbubble generation nozzle is directed toward the central axis of the nozzle body 1 with respect to the liquid that is supplied from the inlet 2 and flows inside the nozzle body 1. Gas is blown into a continuous wide thin film A (hereinafter referred to as "thin film A") along the vertical plane through a slit 4 continuously provided on the side surface, and the blown gas forms a continuous wide thin film A (hereinafter referred to as "thin film A") along the inner surface of the nozzle body 1. The liquid flows as a "layer A"), and fine bubbles B are gradually formed, and a large amount of fine bubbles B are formed near the discharge port 3.

In the above-mentioned fine bubble generation nozzles as shown in FIGS. 7 to 9, a surface perpendicular to the central axis of the nozzle body 1 is applied to the liquid flowing inside the nozzle body 1 made of a cylindrical body. The gas blown through the slits 4 that are continuously provided on the side surface forms a thin layer A and flows along the inner surface of the nozzle body 1, and fine bubbles B are gradually formed. Since a large amount of fine bubbles B are formed near the discharge port 3, the generation efficiency of fine bubbles can be improved, and the fine bubble content of the liquid can be efficiently and sufficiently increased.

The cross-sectional shape of the cylindrical body of the nozzle main body 1 in the above-mentioned fine bubble generating nozzle can be circular or rectangular, but is preferably circular. By making the cross-sectional shape circular, the thickness of the thin layer A can be made uniform, and the content of fine bubbles in the liquid tends to be efficiently increased. The cross-sectional shape of the cylindrical body of the nozzle main body 1 may be a perfect circle as shown in FIG. 9, or may be a substantially perfect circle or an ellipse.

In addition, in the above-mentioned fine bubble generation nozzle, the slit 4 is "provided along a plane perpendicular to the central axis of the nozzle body 1 (hereinafter also referred to as a "vertical plane")"; This means that it is installed roughly along the surface.

Further, it is preferable that a rod-shaped body, preferably a rod-shaped body having a circular cross-sectional shape, be disposed along the central axis of the nozzle main body 1 made of a cylindrical body. As a result, even if the amount of liquid supplied to the nozzle body 1 is the same, the flow rate of the liquid flowing inside the nozzle body 1 (hereinafter also referred to as "liquid flow rate") can be increased, so that the thin layer A can be stably formed, and a liquid containing ultra-fine bubbles or fine bubbles can be efficiently generated.

In order to smoothly form the thin layer A using the fine bubble generation nozzle of the invention of the previous international application,
1) the flow rate of the liquid, and 2) the flow rate of the gas blown from the slit 4 in the direction perpendicular to the flow of the liquid in the nozzle body 1 (hereinafter also referred to as "gas flow rate").
It is necessary to strike an appropriate balance. If the gas flow rate is too high compared to the liquid flow rate, the gas will be blown close to the central axis of the nozzle body 1, making it difficult to form the thin layer A. On the other hand, if the gas flow rate is too low compared to the liquid flow rate, the liquid will leak out from the slit 4 to the outside of the nozzle body 1.

<Gas supply section in the above fine bubble generation nozzle>
As shown in FIG. 10, in the fine bubble generation nozzle described above, a gas supply section 5 that supplies pressurized gas (for example, pressurized air and/or oxygen) is connected to the slit 4. Ru. Preferably, the gas supply unit 5 is airtightly provided outside the nozzle body 1 so as to surround the slit 4 .

The pressure of the gas supplied to the gas supply section 5 (hereinafter also referred to as "gas pressure") is basically set to prevent the liquid from leaking out of the nozzle body 1 from the slit 4. , is preferably higher than the pressure of the liquid flowing inside the nozzle body 1.

On the other hand, when the gas pressure is increased, the gas flow rate also increases, so if the gas pressure is increased too high, the gas flow rate becomes too high compared to the liquid flow rate, making it difficult to form the thin layer A. There is a tendency to

The gas pressure can be set to an appropriate value taking these factors into consideration, but usually the lower limit is set to a pressure (for example, 1.5 atm) at which the liquid does not leak out from the slit 4 to the outside of the nozzle body 1. , 3.0 atm is preferable.

<Slit in the nozzle for generating fine bubbles>
The slit 4 in the fine bubble generation nozzle is formed along a plane perpendicular to the central axis of the nozzle body 1, as shown in FIGS. 7 to 8 and 11 to 13. , are continuous pores on the side.

The gap between the slits 4 can be set to an appropriate value that allows the formation of the thin layer A, taking into account the flow rate of the liquid, the flow rate of the gas, and the pressure of the gas.

In addition, if the gap between the slits 4 is too narrow, the generation efficiency of the microbubbles B will decrease, and if the gap is too wide, it will be difficult to form the microbubbles B from the thin layer A near the discharge port 3, so these factors should also be considered. You can set appropriate values.

The gap between the slits 4 can be set to an appropriate value taking these factors into consideration, but is usually 0.5 mm to 2.0 mm, preferably 0.5 mm to 1.5 mm, and more preferably 0.5 mm to 0.5 mm. Can be set within a range of 8mm.

In order to efficiently increase the microbubble content of the liquid, it is preferable to increase the gas flow rate to increase the amount of gas blown into the liquid. , it becomes difficult to form the thin layer A.

In order to achieve both the above-mentioned "improvement of the fine bubble content of the liquid" and "stable formation of the thin layer A," it is necessary to position the slit 4 on the upstream side with respect to the plane perpendicular to the central axis of the nozzle body 1. It is preferable to incline it to . As a result, even if the gas flow rate itself is increased, the flow rate of the gas in the direction perpendicular to the flow of the liquid in the nozzle body 1, which prevents the formation of the thin layer A, can be reduced. The angle θ that is inclined toward the upstream side with respect to the plane perpendicular to the central axis of the nozzle main body 1 (hereinafter also referred to as "inclination angle θ") is determined depending on the flow rate of the liquid, the flow rate of the gas, etc. It can be made with an acute angle so that it can be formed stably. Considering the above effects, the inclination angle θ is preferably 0° or more and 80° or less, more preferably 60° or more and 80° or less, and even more preferably 70° or more and 80° or less.

Furthermore, in order to achieve both the above-mentioned "improvement of the fine bubble content of the liquid" and "stable formation of the thin layer A," it is also preferable to provide the slits 4 in multiple stages in the nozzle body 1. Thereby, the amount of gas blown can be increased without increasing the gas flow rate itself. It is preferable to have a large number of slits 4 from the viewpoint of increasing the amount of gas blown into the slit 4, but if there are too many stages, the nozzle structure will become complicated and manufacturing and maintenance costs will increase, so these factors should be taken into account. Can be set as appropriate. The number of stages of the slits 4 is usually preferably 1 to 3 stages.

<Slit in the nozzle for generating fine bubbles>
As shown in FIGS. 7 and 8 (first embodiment of the above fine bubble generating nozzle), the slit 4 in the above fine bubble generating nozzle forms a single cylindrical nozzle body 1. It is also possible to form the body 1a by cutting the circumferential surface of the cylindrical body leaving a connection part in a part, or [FIG. 11] (the second embodiment of the nozzle for generating fine bubbles) ), [FIG. 12] (the third embodiment of the nozzle for generating fine bubbles) and [FIG. 13] (the fourth embodiment of the nozzle for generating fine bubbles), the nozzle main body 1 is It is also possible to form the cylindrical bodies 1b, 1c, etc., each having a length larger than 1,000 mm, and form it at the connecting portion of these cylindrical bodies 1b, 1c, etc.

In the second embodiment of the nozzle for generating fine bubbles shown in FIG. 11, the nozzle main body 1 is formed of two cylindrical bodies 1b and 1c each having a circular cross-sectional shape, and these cylindrical bodies 1b, A slit 4 having an inclination angle θ is formed in the connection portion 1c etc., but in this second embodiment, the slit 4 having a small cross-sectional area becomes longer, making cleaning the slit 4 difficult. There is a concern that the pressure of the gas supplied into the section 1 may decrease due to pressure loss.

The third embodiment of the microbubble generating nozzle shown in FIG. 12 eliminates the above concerns, and in the cylindrical body 1c with a circular cross-sectional shape, the cylindrical body 1b with a circular cross-sectional shape and the cylindrical body 1b with a circular cross-sectional shape. The length of the slit 4 is shortened by cutting off the tip of the connecting portion. Thereby, the slit 4 can be easily cleaned and the pressure loss of the gas supplied into the nozzle main body 1 can be reduced.

<Discharge port in the nozzle for generating fine bubbles>
In the above fine bubble generation nozzle, as shown in FIG. 8, the thin layer A separates from the inner surface of the nozzle body 1 near the discharge port 3 to form fine bubbles B, but the thin layer A In order to make it easier to separate from the inner surface of the nozzle body 1, the inner diameter of the nozzle body 1 near the discharge port 3 can be gradually expanded toward the downstream side.

Furthermore, as in the fourth embodiment of the microbubble generating nozzle shown in FIG. 13, irregularities are formed on the inner surface of the nozzle main body 1 near the discharge port 3 to cause turbulence in the flow of the liquid. By doing so, the formation of microbubbles B can be promoted. Means for forming unevenness on the inner surface of the nozzle body 1 include cutting the inner surface of the nozzle body 1 to form a concave portion, and forming a convex portion by bonding a coil-shaped member to the inner surface of the nozzle body 1. Examples include means to do so.

2. Nozzle for generating fine bubbles according to the present invention The nozzle for generating fine bubbles according to the present invention is improved based on the above-mentioned nozzle for generating fine bubbles, and can be easily disassembled and assembled in a short time. It is characterized by the ability to easily inspect and remove deposits and foreign matter.

<First embodiment of the nozzle for generating fine bubbles of the present invention>
The first embodiment of the nozzle for generating fine bubbles of the present invention has one slit in the nozzle body, as shown in [Fig. 1] to [Fig. 3], and [Fig. 1] shows the nozzle before assembly. [FIG. 2] is a schematic cross-sectional view showing the state after assembly of [FIG. 1], and [FIG. 3] is a schematic cross-sectional view showing the state of [FIG. 2]. FIG. 2 is a schematic cross-sectional view showing a bolt and nut as an example.

In the micro bubble generation nozzle of the first embodiment, as shown in FIGS. 1 and 2, a nozzle main body 1 having a cylindrical inner peripheral surface is connected to an upstream nozzle member 6 and a downstream nozzle member. 7, and a connecting member 8 disposed between the upstream nozzle member 6 and the downstream nozzle member 7, is removably fastened and fixed by fastening means 9 such as bolts and nuts as shown in [Fig. 3]. It is formed by In FIG. 2, fastening means 9 such as bolts and nuts are provided at four locations: two upper and lower locations at the front and two upper and lower locations at the rear.

An inlet 2 through which a liquid flows is provided on the upstream side of the upstream nozzle member 6, and an outlet 3 is provided on the downstream side of the downstream nozzle member 7 to discharge a liquid mixed with air bubbles including fine bubbles. Further, the connection member 8 is provided with a connection port 8' for connecting to a gas supply section (see gas supply section 5 in FIG. 10).

Then, when the upstream nozzle member 6, the connecting member 8, and the downstream nozzle member 7 are fastened and fixed in this order, the downstream end 6' of the upstream nozzle member 6 and the upstream side of the downstream nozzle member 7 The end portion 7' forms a continuous slit 4 on the side surface along a plane perpendicular to the central axis of the nozzle body 1, as shown in FIGS. 8 and 11 to 13. Ru.

Like the previous microbubble generation nozzle, the microbubble generation nozzle of the first embodiment can improve the microbubble generation efficiency and sufficiently increase the microbubble content of the liquid. The upstream nozzle member 6, the downstream nozzle member 7, and the connecting member 8, which are the constituent members of the main body 1, are removably fastened by fastening means 9 such as bolts and nuts. It has a unique shape and structure, and can be easily disassembled and assembled in a short time, making it an excellent product that allows for easy inspection and removal of deposits and foreign matter.

The performance of the fine bubble generation nozzle deteriorates if foreign matter adheres to the slit 4, but in the fine bubble generation nozzle of the first embodiment, the deposits and foreign matter on the nozzle body 1 can be easily inspected and removed. Deterioration in the performance of the bubble generation nozzle can be prevented. Particularly, product safety is required in production equipment lines for sanitary products (food, brewing, dairy products, biopharmaceuticals, chemicals, etc.), and the microbubble generation nozzle of the first embodiment Since it has a simple shape and structure and can be easily disassembled and assembled in a short time, cleaning and sterilization can be performed in a short time, and there are no areas where cleaning or sterilization is insufficient.

Further, since the microbubble generating nozzle of the first embodiment has a simple shape and structure and can be disassembled, the inner surface can be easily polished. By sufficiently polishing and smoothing the liquid-contacted parts, it is possible to reduce the adhesion of dirt and improve cleaning performance. Furthermore, when the material of the microbubble generating nozzle is stainless steel, electropolishing can be performed to concentrate chromium on the stainless steel surface and improve corrosion resistance.

<Second embodiment of the nozzle for generating fine bubbles of the present invention>
The second embodiment of the nozzle for generating fine bubbles of the present invention has three slits in the nozzle body, as shown in [Fig. 4] to [Fig. 5], and [Fig. 4] shows the nozzle before assembly. [FIG. 5] is a schematic cross-sectional view showing the state of [FIG. 4] after assembly.

In the micro bubble generation nozzle of the second embodiment, as shown in FIGS. 4 to 5, the nozzle main body 1 having a cylindrical inner peripheral surface is located between the upstream nozzle member 6 and the two intermediate nozzle members. Nozzle members 10-1 and 10-2, downstream nozzle member 7, and connection members 8-1 and 8 disposed between each of the four nozzle members 6, 10-1, 10-2 and 7. -2 and 8-3 are removably fastened and fixed by fastening means 9 such as bolts and nuts as shown in FIG. In FIG. 5, fastening means 9 such as bolts and nuts are provided at four locations: two upper and lower locations at the front and two upper and lower locations at the back.

An inlet 2 through which a liquid flows is provided on the upstream side of the upstream nozzle member 6, and an outlet 3 is provided on the downstream side of the downstream nozzle member 7 to discharge a liquid mixed with air bubbles including fine bubbles. In addition, the connection members 8-1, 8-2, and 8-3 have connection ports 8-1', 8-2', and 8-3 for connecting to the gas supply section (see gas supply section 5 in [Fig. 10]). 3' is provided.

Then, the upstream nozzle member 6, the connecting member 8-1, the intermediate nozzle member 10-1, the connecting member 8-2, the intermediate nozzle member 10-2, the connecting member 8-3, and the downstream nozzle member 7 are connected in this order. When tightened and fixed,
1) The downstream end 6' of the upstream nozzle member 6 and the upstream end 10-1' of the intermediate nozzle member 10-1
2) the downstream end 10-1'' of the intermediate nozzle member 10-1, the upstream end 10-2' of the intermediate nozzle member 10-2, and 3) the downstream end of the intermediate nozzle member 10-2. 10-2'' and the upstream end 7' of the downstream nozzle member 7, the vertical nozzle body 1 is perpendicular to the central axis as shown in FIGS. 8 and 11 to 13. Three consecutive slits 4 are formed on the side surface along this plane.

In the micro bubble generation nozzle of the second embodiment, two intermediate nozzle members (10-1 and 10-2) and three connecting members ( 8-1, 8-2, and 8-3) to provide three stages of slits, but based on the same idea, n intermediate nozzle members and (n+1) connecting members are arranged. As a result, (n+1) stages of slits can be provided. Note that n is an integer of 1 or more.

The fine bubble generation nozzle of the second embodiment, like the previous fine bubble generation nozzle, can improve the generation efficiency of fine bubbles and efficiently and sufficiently increase the fine bubble content of the liquid. Like the microbubble generation nozzle of the embodiment, it has a non-complicated shape and structure, can be easily disassembled and assembled in a short time, can easily inspect and remove deposits and foreign matter, and can be installed in multiple stages. By providing the slits, it is possible to more efficiently generate a liquid containing microbubbles.

Further, the micro bubble generation nozzle of the second embodiment can increase the number of slit stages by changing the number of intermediate nozzle members and connecting members arranged between the upstream nozzle member 6 and the downstream nozzle member 7. Since it can be easily and freely changed, the performance of the fine bubble generation nozzle can be set according to the required conditions.

<Tightening means for bolts, nuts, etc. used in the microbubble generation nozzle of the present invention>
As for the fastening means such as bolts and nuts used in the micro bubble generation nozzle of the present invention, when used as a nozzle, structural members such as an upstream nozzle member, a downstream nozzle member, a connecting member, and an intermediate nozzle member are used. (hereinafter also referred to as "component members") can be easily and firmly fastened together, and can be easily disassembled when inspecting and removing deposits and foreign matter, as well as cleaning and sterilizing. Fastening means can be used.

A suitable example of fastening is to use a bolt with male threads at both ends and two nuts that are screwed into the male threads of this bolt, as shown in Figure 3, and insert the bolt into the through hole of the component. The components can be tightened by passing nuts through the bolt and screwing nuts onto both ends of the bolt. Furthermore, each component can be fastened with improved sealing performance using a ferrule type piping joint technique. Alternatively, the arranged structural members can be tightened by tightening screws so as to sandwich them from both ends.

<Material of the nozzle for generating fine bubbles of the present invention>
As the material of the nozzle for generating fine bubbles of the present invention, any known material used as a material for ordinary nozzles can be employed.

Preferably, stainless steel such as SUS304 (austenitic stainless steel containing chromium and nickel) and SUS316L (austenitic stainless steel with increased nickel content and molybdenum added to SUS304) can be used. When stainless steel is used, electrolytic polishing can make the liquid contact part of the microbubble generation nozzle ultra-smooth at the nano level, reducing the adhesion of dirt and improving cleaning performance. In addition, electrolytic polishing can form an oxide film in which chromium is condensed on the liquid contact part of the microbubble generation nozzle, thereby improving corrosion resistance. In addition, from the viewpoint of improving corrosion resistance, titanium, a corrosion-resistant alloy such as Hastelloy (registered trademark), Teflon (registered trademark), etc. can be used as the material of the nozzle for generating fine bubbles. In addition, from the viewpoint of improving wear resistance, a nitrided alloy subjected to plasma nitriding, radical nitriding, etc., an alloy subjected to hardening treatment such as induction hardening, etc. can be used as the material of the micro bubble generation nozzle.

3. Application of the nozzle for generating fine bubbles of the present invention The nozzle for generating fine bubbles of the present invention improves the generation efficiency of fine bubbles and can efficiently and sufficiently increase the fine bubble content of the liquid. Utilizes the effect of increasing dissolved oxygen concentration (DO), sterilization and sterilization effects, etc.
〇Manufacture and supply of shower water, bathtub water, washing water, washing water, etc.
〇 Wastewater treatment such as wastewater generated from various industries such as food plants, pulp plants, chemical plants, domestic wastewater, etc.
〇Seafood farming〇It can be used in a wide range of fields such as chemical reactions and biological reactions.

Furthermore, the nozzle for generating fine bubbles of the present invention has an uncomplicated shape and structure, and can be easily disassembled and assembled in a short time. It can be suitably used in manufacturing equipment lines for dairy products, biopharmaceuticals, chemical products, etc., and can be particularly suitably used in biopharmaceutical manufacturing plants where product safety is important. In other words, in sanitary product manufacturing equipment lines, cleaning and sterilization such as CIP cleaning (Cleaning In Place) is performed every time a product is changed and/or periodically to ensure product safety. The nozzle for generating fine bubbles of the present invention has an uncomplicated shape and structure, and can be easily disassembled and assembled in a short time. Therefore, it is possible to easily inspect and remove deposits and foreign substances, and shorten cleaning and sterilization. It can be done in a short amount of time, and there are no areas that are insufficiently cleaned or sterilized.

Furthermore, the nozzle for generating fine bubbles of the present invention can be suitably used in chemical reactions that use a reaction solution in which a solid catalyst is dispersed as a liquid, and biological reactions that use a culture solution containing microorganisms and the like as a liquid. In other words, solid catalysts used in chemical reactions are easily broken, and the activity of microorganisms used in biological reactions decreases due to stress and damage. Since the solid catalyst acts as a cushion to prevent microorganisms and the like from colliding with the inner surface of the nozzle body 1, it is possible to reduce damage to the solid catalyst and stress and damage to the microorganisms and the like. In addition, with the microbubble generation nozzle of the present invention, the content of microbubble can be efficiently and sufficiently increased even if the flow rate of the liquid is reduced, thereby reducing damage to the solid catalyst and stress and damage to microorganisms, etc. can.

4. Among biological reaction devices using the microbubble generation nozzle of the present invention , the microbubble generation nozzle of the present invention cultivates microorganisms or cells ranging from aerobic to anaerobic (hereinafter also referred to as "microorganisms, etc."). Therefore, it can be particularly suitably used in a biological reaction device in which microorganisms or the like are made to produce reaction products or to grow microorganisms or the like.

In the bioreactor shown in [Figure 6],
1) extracting the biological culture solution 11 containing the culture solution and microorganisms from the culture tank 12;
2) A step of supplying the extracted biological culture solution 11 to a microbubble generation tank 13 to contain microbubbles by the microbubble generator 14, and 3) A step of supplying the biological culture solution 11 containing microbubbles to a reflux pipe. A biological reaction is carried out by the process of returning the microbubble to the culture tank 12 through the microbubble generating device 14. By using the microbubble generating nozzle of the present invention as the microbubble generator 14, as shown in FIG. serves as a cushion to prevent microorganisms and the like from colliding with the inner surface of the nozzle body 1, thereby reducing stress and damage to the microorganisms and the like.

Furthermore, by using a fine bubble generation nozzle that can efficiently generate a liquid with a high content of fine bubbles according to the present invention as the "fine bubble generator 14," the liquid is extracted from the culture tank 12 and cultured after containing fine bubbles. The amount of the biological culture solution 11 flowing back into the tank 12 can be set as low as 1% or more and less than 80%, preferably 33% or more and less than 60%, of the amount of the biological culture solution 11 contained in the culture tank 12 per minute. Therefore, the stress and damage that microorganisms receive due to liquid circulation can be reduced.

Note that if the amount of the biological culture solution 11 flowing back into the culture tank 12 is too small, it will not be able to provide sufficient oxygen to the microorganisms, resulting in a decrease in the activity of the microorganisms, and if it is too large, it will cause stress and damage to the microorganisms. Therefore, an appropriate value can be set in consideration of these factors and according to the type of microorganisms, the concentration of microorganisms, etc. in the biological culture solution 11, etc.

<Method of mixing bubbles including microbubbles into liquid>
The method of mixing bubbles containing microbubbles into the liquid of the present invention can be carried out using the above-described nozzle for generating microbubbles, and can be carried out simply and economically by efficiently and sufficiently increasing the content of microbubbles to form a liquid. It is possible to mix air bubbles including fine air bubbles into the air.

Next, the nozzle for generating fine bubbles of the present invention will be explained using Examples and Comparative Examples, but the present invention is not limited to these Experimental Examples and Comparative Experimental Examples.

<Examples 1-2/Comparative Examples 1-2>
In Examples 1 and 2 and Comparative Examples 1 and 2 below, as summarized in Table 1, microbubble generating nozzles having the following shapes and structures were used.
〇Nozzle main body: Cylindrical body with a circular cross-section and an inner diameter of 6.0 mm 〇Slits or holes provided in the nozzle main body:
[Example 1] An angle θ inclined toward the upstream side with respect to the plane perpendicular to the central axis of the nozzle body, which is continuously provided on the side surface along the plane perpendicular to the central axis of the nozzle body, is 0. °, a slit with a gap of 0.8 mm [Example 2] A slit that is continuously provided on the side surface along a plane perpendicular to the central axis of the nozzle body. [Comparative Example 1] Slits that are inclined upstream at an angle θ of 75° and have a gap of 0.8 mm. [Comparative Example 1] Slits are continuously provided on the side surface at equal intervals along a plane perpendicular to the central axis of the nozzle body. , the angle θ inclined upstream with respect to the plane perpendicular to the central axis of the nozzle body is 0°, and three holes with a diameter of 1.0 mm [Comparative Example 2] In the plane perpendicular to the central axis of the nozzle body 3 holes/slits with a diameter of 2.0 mm, each having an angle θ of 0° on the upstream side with respect to a plane perpendicular to the central axis of the nozzle body, which are continuously provided at equal intervals on the side surface. Or number of holes: 1 stage

An aqueous solution of glucose with a concentration of 10% by mass (hereinafter referred to as "glucose aqueous solution") was flowed into the fine bubble generation nozzles of Examples 1 and 2 and Comparative Examples 1 and 2 from the inlet at one end of the nozzle body. : At the same time, air was supplied at a rate of 16 m/sec, and air was supplied at an aeration rate of 30 L/min from a slit or hole provided in the nozzle body to obtain a glucose aqueous solution mixed with fine air bubbles.

The KLA [mass transfer capacity coefficient (/h)] of the aqueous glucose solution mixed with the obtained air microbubbles was measured. The results are shown in Table 2.

KLA [mass transfer capacity coefficient (/h)] is generally used as an index to express the dissolved oxygen concentration (DO) of a liquid, and the larger the value, the higher the dissolved oxygen concentration of the liquid. There is. In other words, in order for oxygen in the air to dissolve in a liquid and become dissolved oxygen, oxygen molecules _O2 in the gas phase must move into the liquid, and this oxygen transfer rate OTR is expressed by the following general formula (1). Therefore, the larger the value of KLA, the higher the dissolved oxygen concentration of the liquid.
OTR=KLA×( _CS -C)...(1)
In this formula (1),
OTR: Oxygen transfer rate (mg/L・h)
KLA: mass transfer capacity coefficient (/h)
C _S : Saturation solubility of oxygen in water (mg/L)
C: Solubility of oxygen in water (mg/L).

From the comparison between Examples 1 and 2 (the shape of the air supply port is "slit") and Comparative Examples 1 and 2 (the shape of the air supply port is "hole"), the shape of the air supply port provided in the nozzle body is It can be seen that by using ``slits'', the dissolved oxygen concentration in the liquid can be made much higher than when using ``holes'' (Comparative Examples 1 and 2).

Furthermore, from a comparison between Example 1 (angle θ is 0°) and Example 2 (angle θ is 75°), it was found that by making the slit incline toward the upstream side with respect to the plane perpendicular to the central axis of the nozzle body, It can be seen that the dissolved oxygen concentration in the liquid can be increased.

In addition, in the glucose aqueous solution in which the air microbubbles obtained in Example 2 (the shape of the air supply port is "slit") and Comparative Example 1 (the shape of the air supply port is "hole") are mixed, The bubble size distribution of the bubbles was measured using an image analysis particle size measuring device (manufactured by Microtrack Bell). Table 3 shows the bubble size distribution of Example 2, and Table 4 shows the bubble size distribution of Comparative Example 1.

The bubble distributions shown in Tables 3 and 4 were measured for 1 minute using the above measuring device, and the horizontal axis shows the particle diameter (μm) of the bubbles, and the vertical axis shows the diameter of each bubble relative to the total number of bubbles measured. The percentage of air bubbles (%) is shown.

Bubble size distribution (Table 3) of micro air bubbles in Example 2 (the shape of the air supply port is “slit”) and Comparative Example 1 (the shape of the air supply port is “hole”) A comparison with the diameter distribution (Table 4) shows that by making the air supply port provided in the nozzle body into a "slit" shape, the diameter of the micro air bubbles can be made smaller and the air bubbles can be reduced compared to when the air supply port is made into a "hole". It can be seen that the diameter distribution can be sharpened.

1 Nozzle body part 1a Cylindrical body 1b Cylindrical body 1c Cylindrical body 2 Inflow port 3 Discharge port 4 Slit 5 Gas supply part 6 Upstream nozzle member 6' Downstream end of upstream nozzle member 7 Downstream nozzle member 7 ' Upstream end of downstream nozzle member 8 Connection member 8' Connection port with gas supply section 8-1 Connection member 8-1' Connection port with gas supply section 8-2 Connection member 8-2' Gas supply section Connection port with 8-3 Connection member 8-3' Connection port with gas supply section 9 Bolt/nut which is an example of fastening means 10-1 Intermediate nozzle member 10-1' Upstream end of intermediate nozzle member 10 -1'' Downstream end of intermediate nozzle member 10-2 Intermediate nozzle member 10-2' Upstream end of intermediate nozzle member 10-2'' Downstream end of intermediate nozzle member 11 Biological culture solution 12 Culture tank 13 Fine bubble generation tank 14 Fine bubble generation device 110 Aeration device 111 Nozzle main body 112 Inflow port 113 Discharge port 114 Air jet port 120 Aeration device 121 Pressurized water supply pipe 122 First stage nozzle member 123, 124 From one stage or multiple stages Nozzle members of the bubble maturation zone 125, 126 Ring slit-shaped nozzles A (formed along the inner surface of the nozzle body) Continuous wide thin layer of gas A' (formed along the inner surface of the nozzle body) B) Microbubbles B' Microbubbles

Claims (10)

A nozzle for generating fine bubbles for mixing ultra fine bubbles or fine bubbles in a liquid to produce a liquid containing the fine bubbles, the nozzle comprising:
Consisting of a nozzle main body having a cylindrical inner circumferential surface and a gas supply section supplying gas to the inner circumferential surface of the nozzle main body,
The nozzle main body is composed of an upstream nozzle member, a downstream nozzle member, and a connecting member disposed between the nozzle members, and the three members are removably fastened by fastening means such as bolts and nuts. It is formed by attaching and fixing it,
An inlet into which liquid flows is provided on the upstream side of the upstream nozzle member,
A discharge port is provided on the downstream side of the downstream nozzle member for discharging a liquid mixed with bubbles including the microbubbles,
A slit is formed continuously on a side surface along a plane perpendicular to the central axis of the nozzle body by the downstream end of the upstream nozzle member and the upstream end of the downstream nozzle member. A nozzle for generating fine bubbles. A nozzle for generating fine bubbles for mixing ultra fine bubbles or fine bubbles in a liquid to produce a liquid containing the fine bubbles, the nozzle comprising:
Consisting of a nozzle main body having a cylindrical inner circumferential surface and a gas supply section supplying gas to the inner circumferential surface of the nozzle main body,
The nozzle main body includes an upstream nozzle member, n intermediate nozzle members (n represents an integer of 2 or more), a downstream nozzle member, and a connecting member disposed between each of the plurality of nozzle members. All of the above-mentioned members are removably fastened and fixed using fastening means such as bolts and nuts,
An inlet into which liquid flows is provided on the upstream side of the upstream nozzle member,
A discharge port is provided on the downstream side of the downstream nozzle member for discharging a liquid mixed with bubbles including the microbubbles,
1) a downstream end of the upstream nozzle member and an upstream end of the intermediate nozzle member located first from the upstream side;
2) The downstream end of the intermediate nozzle member located mth from the upstream side (m represents an integer greater than or equal to n and less than n) and the upstream end of the intermediate nozzle member located (m+1)th from the upstream side. and 3) a downstream end of the n-th intermediate nozzle member from the upstream side and an upstream end of the downstream nozzle member to form a plane perpendicular to the central axis of the nozzle body. A nozzle for generating fine bubbles, characterized in that a slit is continuously formed on the side surface along the . 3. The nozzle for generating fine bubbles according to claim 1, wherein the slit has an acute angle θ inclined toward the upstream side with respect to a plane perpendicular to the central axis of the nozzle body. The nozzle for generating fine bubbles according to any one of claims 1 to 3, wherein the inner diameter of the downstream nozzle member near the discharge port is gradually expanded toward the downstream side. The fine bubble generating nozzle according to any one of claims 1 to 4, characterized in that the nozzle for generating fine bubbles is used for manufacturing equipment for sanitary products such as food, brewing, biopharmaceuticals, dairy products, and chemicals. Nozzle for generating air bubbles. The nozzle for generating fine bubbles according to any one of claims 1 to 4, characterized in that the nozzle for generating fine bubbles is used for chemical reactions. The nozzle for generating fine bubbles according to any one of claims 1 to 4, characterized in that the nozzle for generating fine bubbles is used for biological reactions. A method of mixing bubbles containing ultra-fine bubbles to fine bubbles into a liquid using the micro-bubble generating nozzle according to any one of claims 1 to 7. a culture tank containing a culture solution and a biological culture solution containing microorganisms or cells ranging from aerobic to anaerobic;
The nozzle for generating fine bubbles according to any one of claims 1 to 4, wherein the biological culture solution extracted from the culture tank contains bubbles including ultra fine bubbles or fine bubbles.
a pipe line for circulating the biological culture solution containing the microbubbles to the culture tank;
A biological reaction device comprising: The amount of biological culture fluid that is extracted from the culture tank and returned to the culture tank after containing bubbles including ultra-fine bubbles or fine bubbles is the amount of biological culture fluid contained in the culture tank per minute. The bioreactor according to claim 9, characterized in that the amount is set to 1% or more and less than 80% of the amount of .

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