JP7511232B2 - Gas-liquid mixing device - Google Patents

Description

The present invention relates to a gas-liquid mixing device that mixes fine gas bubbles in a liquid.

2. Description of the Related Art A stirring and mixing device (gas-liquid stirring device) that generates a large number of fine bubbles in a liquid in order to efficiently stir and mix a gas such as air in a liquid such as water is known (for example, Patent Document 1).
This device is configured with a straight cylindrical outer shell 2 with an upper end opening 4 open to the air and positioned to protrude above the liquid surface, and a straight columnar or straight cylindrical driver 1 that is coaxially inserted and assembled over the entire length of the outer shell 2 and rotated at high speed. When the driver 1 inside the outer shell 2 is rotated at high speed in water, the air drawn into the water by the vortex motion is vigorously mixed with the water and broken down into extremely fine bubbles, which are forcefully discharged downward from the lower end opening 5 of the outer shell 2 together with the water. When the water mixed with the fine bubbles is discharged to the outside from the lower end opening 5 of the outer shell 2 due to the high-speed rotation of the driver 1, the liquid level in the gap 7 formed between the outer shell 2 and the driver 1 will drop, but since a window hole 6 is opened in the cylindrical wall 3 of the outer shell 2 directly below the liquid surface, water is constantly supplied into the gap 7 through this window hole 6.

Japanese Patent Application Laid-Open No. 5-7752

However, in the invention described in Patent Document 1, the position of the liquid level in the gap 7 is configured to change in accordance with the position of the liquid level outside the outer shell body 2. For this reason, if the water level changes significantly, for example, if the position of the liquid level outside the outer shell body 2 changes to a position lower than the window hole 6, the position of the liquid level in the gap 7 also drops accordingly, and water is no longer supplied from the window hole 6. This causes the problem that the amount of water released to the outside from the lower end opening 5 becomes unstable.

The present invention aims to solve the problems of the conventional technology described above by creating a gas-liquid mixing device that suppresses the effects of liquid level displacement and can stably supply gas-liquid in which fine bubbles are mixed and stirred into the liquid.

Among the means for solving the above problems, the main means of the present invention is:
A gas-liquid mixing device comprising: a double cylinder body having a straight cylindrical shape, a part of which is submerged in a liquid to be stirred; a gas supply pipe for supplying a predetermined gas from the outside into the double cylinder body; a blade unit disposed inside the double cylinder body for shearing the gas at high speed to generate fine bubbles and stir and mix the gas into the liquid; a drive unit for rotating the blade unit at high speed; and a discharge unit for discharging the stirred and mixed gas-liquid into the liquid,
The double cylinder is formed having an inner cylinder portion and an outer cylinder portion arranged on a concentric axis, and a gap is formed between the inner cylinder portion and the outer cylinder portion to raise the liquid by utilizing capillary action , and a window hole is formed at a predetermined height position of the inner cylinder portion which radially connects the gap to the inside of the inner cylinder portion and supplies the raised liquid into the inner cylinder portion .
The main feature of the present invention is that the supply of liquid to the inner cylinder is achieved by utilizing the capillary phenomenon that occurs in the gap between the inner cylinder and the outer cylinder, thereby making it possible to consistently and stably supply a constant amount of liquid to the inner cylinder.

Another aspect of the present invention is to add a water intake port between the lower end of the outer cylinder and the discharge portion to the above-mentioned main aspect.
With the above-mentioned means, the water intake can be provided at the lower end of the double cylinder body 20A, which is made of a straight cylindrical shape and constitutes the fine bubble generating section, making it less susceptible to the effects of liquid level displacement.

The present invention reduces the effects of external liquid level changes and can consistently provide a stable gas-liquid mixture with fine bubbles stirred into the liquid.

1 is a partial cross-sectional view of a gas-liquid mixing device showing an embodiment of the present invention. 2 is a cross-sectional view taken along line AA in FIG. 1. FIG. 2 is a partial cross-sectional view showing an example of use of the gas-liquid mixing device.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
As shown in Figure 1, the gas-liquid mixing device 1 of the present invention is configured with a flat flange 2 serving as an attachment base, a drive unit 10 provided on the upper side of the flange 2, and a fine bubble generating unit 20 provided on the lower side of the flange 2.

The drive unit 10 is composed of a DC or AC motor (not shown) and a housing 11 that houses the motor, and is assembled on the flange 2 with the motor's rotating shaft 12 extending downward toward the fine bubble generating unit 20 through a through hole 2a drilled in the flange 2. An electric cable 13 is connected to the housing 11 to supply power to the motor and to send signals that control the rotation of the motor.

The fine bubble generating section 20 is configured with a double cylinder 20A having a linear cylindrical shape consisting of an inner cylinder 21 and an outer cylinder 22 arranged concentrically, a stirring mechanism 30 provided inside the inner cylinder 21 constituting the double cylinder 20A, a discharge section 40 provided at the lower end of the double cylinder 20A, and a gas supply pipe 50 that supplies gas from the outside into the inner cylinder 21 constituting the double cylinder 20A. The lower surface of the flange 2 and the upper surface of the discharge section 40 are connected via multiple (three in this embodiment) reinforcing pillars 25 arranged outside the double cylinder 20A.

The upper ends of the inner cylinder portion 21 and the outer cylinder portion 22 that constitute the double cylinder body 20A are connected and fixed to the underside of the flange 2, and the inner cylinder portion 21 and the outer cylinder portion 22 are arranged radially opposite each other through a gap 23 consisting of a straight cylindrical space provided between them.
Further, at a predetermined height position of the inner cylindrical portion 21, a window hole 22A for injecting liquid is formed, which radially connects the gap 23 and the inside of the inner cylindrical portion 21.

The stirring mechanism 30 is formed by having a shaft 31 connected to the lower end of the rotating shaft 12, and a plurality of blade portions 32 provided at a plurality of height positions of the shaft 31. When the motor is driven and the shaft 31 connected to the rotating shaft 12 rotates at high speed together with the blade portions 32 inside the inner cylinder portion 21, a gas-liquid 80 in which the gas 70 and the liquid 61 are stirred and mixed is generated.
The lower end of the inner cylinder portion 21 is fixedly connected to a discharge portion 40 , and the mixed gas-liquid 80 can be discharged from a discharge port 41 provided in the discharge portion 40 .
In addition, the lower end of the outer tube portion 22 is not connected to the discharge portion 40 but is open in a ring shape, and serves as a water intake port 22a that takes in external liquid 61 into the gap 23, and this water intake port 22a is connected to the inside of the inner tube portion 21 via the gap 23 and the window hole 22A.

Next, the operation of the gas-liquid mixing device having the above configuration will be described.
In the following, a case will be described in which gas 70 such as air is converted into fine bubbles 71, called microbubbles, nanobubbles, fine bubbles, or the like, and stirred and mixed in liquid 61 such as water stored in a treatment tank 60.
3, in the gas-liquid agitation device 1, the fine bubble generating unit 20 below the flange 2 is submerged in the liquid 61 in the treatment tank 60. At this time, the upper end of the gas supply pipe 50 is disposed above the liquid surface 62, and gas 70 consisting of air or the like is taken into the inner cylindrical portion 21 constituting the double cylindrical body 20A through the gas supply pipe 50.

The liquid 61 also enters the gap 23 between the inner and outer cylinders 21 and 22 from the water intake port 22a provided at the lower end of the outer cylinder 22. The liquid 61 that has entered can move upward within the gap 23 due to capillary action, and the rising liquid 61 is supplied to the inside of the inner cylinder 21 through the window hole 22A.
When the drive unit 10 is driven to rotate the motor, the multiple blades 32 attached to the shaft 31 rotate at high speed, causing a vortex motion, which draws the gas 70 into the liquid 61 while shearing it at high speed, and vigorously mixing it with the liquid 61 to break it down, generating a gas-liquid 80 in which extremely fine bubbles 71 are mixed and stirred in the liquid 61.
Such gas-liquid 80 then forms a swirling flow and is discharged into the liquid 61 in the treatment tank 60 from the discharge port 41 provided in the lower discharge section 40 .

In the present invention, the liquid 61 that seeps in through the water intake 22a is supplied to the inside of the inner cylinder 21 by capillary action occurring in the gap 23. Therefore, even if the liquid level 62 of the liquid 61 in the treatment tank 60 is significantly displaced up and down, it is difficult to be affected and a constant amount of liquid 61 can be constantly supplied to the inside of the inner cylinder 21. Therefore, the gas-liquid mixing device 1 of the present invention can suppress the effects of displacement of the liquid level and can constantly release the gas-liquid 80 in which the fine bubbles 71 are stirred and mixed stably.

Although the configuration and effects of the present invention have been described above based on the embodiments, the present invention is not limited to the above embodiments.
For example, in the above embodiment, a case has been described in which one window hole 22A is provided in the inner tube portion 21, but the present invention is not limited to the above embodiment, and a configuration in which two or more window holes are provided may also be used.
In the above embodiment, the liquid 61 is water and the gas 70 is air. However, the present invention is not limited to the above embodiment and may use other types of liquids and gases.

The present invention can expand the range of applications in the field of gas-liquid mixing devices that mix and stir fine bubbles into liquids.

1: Gas-liquid mixing device 2; flange 10: drive unit 11: housing 12: rotating shaft 13: power cable 20: fine bubble generating unit 20A: double cylinder 21: inner cylinder 22: outer cylinder 22A: window hole 22a: water intake 23: gap 25: support 30: mixing mechanism 31: shaft 32: blade 40: discharge unit 41: discharge port 50: gas supply pipe 60: treatment tank 61: liquid 70: gas 71: fine bubbles 80: gas-liquid (mixture of liquid and fine bubbles)

Claims (2)

A gas-liquid stirring device comprising: a double cylinder body (20A) having a straight cylindrical shape, a part of which is submerged in a liquid (61) to be stirred; a gas supply pipe (50) for supplying a predetermined gas (70) from the outside into the inside of the double cylinder body (20A); a blade section (32) disposed inside the double cylinder body (20A) for shearing the gas (70) at high speed to generate fine bubbles (71) and stirring and mixing the gas (70) in the liquid (61); a drive section (10) for rotating the blade section (32) at high speed; and a discharge section (40) for discharging the stirred and mixed gas-liquid (80) into the liquid (61),
The gas-liquid mixing device is characterized in that the double cylinder (20A) is formed having an inner cylinder portion (21) and an outer cylinder portion (22) arranged concentrically, a gap (23) is formed between the inner cylinder portion (21) and the outer cylinder portion (22) for raising the liquid (61) by utilizing capillary action, and a window hole (22A) is formed at a predetermined height position of the inner cylinder portion (21) to radially connect the gap (23) and the inside of the inner cylinder portion (21) and supply the raised liquid (61) into the inner cylinder portion (21) . The gas-liquid mixing device according to claim 1, wherein a water intake (22a) is formed between the lower end of the outer cylinder portion (22) and the discharge portion (40).

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