JPS5938815B2 - Microbubble release device in liquid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for emitting fine bubbles in a liquid.

A method in which inert gas such as nitrogen gas and argon gas is released in the form of bubbles into molten aluminum to remove hydrogen gas in molten aluminum or non-metallic inclusions such as oxides of aluminum and magnesium. For example, there is a gas-liquid contact method in which gas is released in the form of bubbles into a liquid in order to promote chemical reactions, but in either case, in order to improve the contact between the gas and liquid, the bubbles must be made as fine as possible. , uniform dispersion is required.

SUMMARY OF THE INVENTION An object of the present invention is to provide a device for emitting fine bubbles in a liquid, which meets the above-mentioned needs, has a simple structure, and is easy to operate.

The first aspect of the present invention is to provide a liquid tank, a vertical hollow rotating shaft, and a bubble microscopic device attached to the lower end of the rotating shaft and disposed below the liquid surface at a predetermined distance from the bottom of the liquid tank. The hollow part of the hollow rotating shaft serves as a gas supply path, the bottom of the rotating body is a flat surface, and the lower end of the gas supply path opens into the bottom flat surface of the rotating body. This is a device for emitting fine bubbles in a liquid. A second aspect of the invention is that in the first device for atomizing and releasing bubbles in a liquid, a recess is provided in the center of the bottom flat surface of the rotating body, and the lower end of the gas supply path of the rotating shaft is recessed. It opens into the facility.

A third aspect of the present invention is that in the first device for atomizing and discharging bubbles in a liquid, a plurality of grooves are formed in the bottom flat surface of the rotating body in a radial pattern extending from the opening of the gas supply path to the periphery thereof. It is provided in

A fourth aspect of the present invention is that in the first device for atomizing and discharging bubbles in a liquid, a recess is provided in the center of the flat bottom surface of the rotating body for air atomization, and the bottom flat surface is flattened from the recess. A plurality of grooves extending to the periphery of the surface are provided radially, and the lower end of the gas supply path of the hollow rotating shaft opens into the recess.

The present invention will be described below with reference to embodiments shown in the drawings. In FIG. 1, the apparatus for atomizing and discharging bubbles in a liquid according to the present invention includes a liquid tank 1, a vertical hollow conduit. Rotating axis 2 and
It consists of a rotary body 3 for bubble miniaturization attached to the lower end of a hollow rotary shaft 2 in the center and located below the liquid level.

A liquid tank 1 contains molten aluminum 4. Further, a vertical cladding tube 5 surrounding the rotating shaft 2 is arranged in the center of the liquid tank 1. The upper end of the cladding tube 5 is attached to the lid 6 of the liquid tank 1, and the upper end of the tube 5 is open to the upper surface of the lid 6. The hollow rotary shaft 2 is inserted through the cladding tube 5 , its upper end extends above the lid 6 , and its lower end projects downward from the lower end opening of the cladding tube 5 . The rotating shaft 2 is configured to be rotated by a rotation drive device (as shown in the figure) at its upper end.The hollow portion of the hollow rotating shaft 2 is connected to a gas supply device (not shown). A male threaded portion is formed on the outer circumferential surface of the lower end of the hollow rotating shaft 2.The rotating body 3 for air bubble refinement is
It has a disk shape with a flat lower surface, and a through hole 8 is bored in the center thereof. A female thread is formed at the upper end of the through hole 8 . The rotary body 3 is attached to the rotary shaft 2 by screwing the male screw portion of the hollow rotary shaft 2 into this female screw portion, and the gas supply path 7 of the rotary shaft 2 is connected to the rotary body through the through hole 8. It opens at the center of the bottom surface. In the bubble atomization release device as described above, the rotating shaft 2
is rotated at high speed by the drive device, and inert gas is supplied to the supply path 7 from the gas supply device.

The inert gas is supplied to the bottom surface of the rotating body 3 from the lower end of the supply path 7 through the through hole 8 . Then, the inert gas spreads outward from the center along the bottom surface of the rotating body 3, and a thin inert gas layer 9 is formed along the bottom surface of the rotating body 3 due to the hydraulic pressure. Then, due to the centrifugal force generated by the rotating action of the rotating body 3, the inert gas layer 9 is divided into fine bubbles 10 which are released from the periphery of the rotating body 3. As shown by the arrow, the bubbles 10 first advance diagonally downward, hit the tank bottom, advance toward the peripheral wall of the liquid tank 1, and rise while spreading over the entire molten aluminum 4. In this embodiment, since the hollow rotating shaft 2 is covered with the cladding tube 5, the reaction products floating on the liquid surface are generated by the vortex generated around the shaft 2 due to the rotation of the rotating shaft 2. It is possible to prevent impurities from being involved and having a negative effect on the molten aluminum. However, the above-mentioned vortex is generated only at the rotating shaft 2.
The rotation speed is 3000r. p. This is when it becomes quite large, such as when it exceeds m, and when it is less than that,
For the cladding tube 5, the shape and size of the rotating body, the rotation speed, the distance of the rotating body from the bottom of the liquid tank, etc. are important in order to make bubbles that are not necessarily necessary as fine as possible and release them uniformly into the liquid. Become a factor.

The rotating body preferably has a disc shape.

It is preferable that the rotating body has a larger diameter. The higher the rotation speed, the better, usually 700 to 3000 r. p. m is good. The rotation speed is 700r. p. If the temperature is less than 3000r.m, the bubbles will not become finer. p. If the rotating shaft is not covered with a cladding tube, a vortex will be generated around the rotating shaft, and reaction products and impurities floating on the liquid surface will be engulfed in the liquid. It may cause negative effects. The distance between the bottom of the rotating body and the bottom of the liquid tank is preferably 5 to 100 Trrm. If it is less than 5wrr1, there is a risk that the rotating body will come into contact with the bottom of the tank, and if it exceeds 100wn, the bubbles may not be distributed throughout the tank, and the density of microbubbles in various parts of the liquid may become uneven. be.

The gas supply pressure must be equal to or higher than the hydrostatic pressure. The amount of gas supplied is determined by the size of the liquid tank, but if it is too small, gas-liquid contact will be insufficient, and if it is too large, it will be difficult to make the bubbles finer and the efficiency of gas-liquid contact will deteriorate. FIGS. 2 to 6 show other examples of the rotary body for making bubbles according to the present invention.

In FIG. 2, the bubble-refining rotating body 13 is provided with a concave recess 14 in the center of the bottom surface, and the lower end of the gas supply path 7 in the rotating shaft 2 is opened at the bottom of the recess 14. There is.

When such a rotary body 13 is used, the gas supplied from the gas supply device through the gas supply path 7 is temporarily transferred to the recess 1.
After accumulating in the liquid, the rotating body 13 rotates to release the microbubbles radially into the liquid, making it possible to emit microbubbles more uniformly into the liquid than when no recesses are provided. can. In FIGS. 3 and 4, a plurality of grooves 24 are radially provided on the bottom surface of the rotary body 23 for air bubble refinement, extending from the lower end of the through hole 8 formed in the center of the rotary body 23 to the periphery. There is.

When such a rotating body 23 is used, the hollow rotating shaft 2
The gas supplied from the internal gas supply path 7 is supplied to each groove 24.
At the same time, a gas layer is created on the bottom surface of the rotary body 23 in between, and the gas is dispersed and enters each groove 24, and due to the rotation of the rotary body 23, fine particles are released from the peripheral edge of the rotary body 23 and the peripheral end of each groove 24. It is released in the form of bubbles. Therefore, the bubbles are further promoted to become finer than those without grooves, and are uniformly released throughout the liquid. Furthermore, groove 2
4 is provided, the molten metal 4 is stirred by the rotation of the rotating body 23, and the bubbles 10 are more uniformly dispersed in the molten metal 4. In FIGS. 5 and 6, the bubble-refining rotating body 33 is provided with a concave recess 34 in the center of the bottom surface, and a plurality of grooves 35 extending from this recess 34 to the periphery of the bottom surface.
are arranged radially.

The lower end of the gas supply path 7 is connected to the recess 3 through the through hole 8.
It opens at the bottom of No. 4. When such a rotating body 33 is used, the gas supplied through the gas supply path 7 once enters the recess 34 and then forms a gas layer on the bottom surface of the rotating body 33 between the grooves 35. The gas is dispersed and enters each groove 35, and is released as fine bubbles by the rotation of the rotating body 33. Furthermore, the bubbles are uniformly dispersed due to the stirring action caused by the rotation of the rotating body 33. Therefore, miniaturization of bubbles and uniform release of bubbles are further promoted compared to a structure in which the recesses 34 and grooves 35 are not provided. According to the apparatus for atomizing and discharging bubbles in a liquid according to the present invention, bubbles can be sufficiently miniaturized and discharged into a liquid as described above. Further, the device for atomizing and discharging bubbles in a liquid according to the present invention includes a liquid tank, a hollow rotating shaft that is vertical and has a gas supply path provided therein, and a hollow rotating shaft that is attached to the lower end of the rotating shaft and located below the liquid level. The structure is simple because the lower end of the gas supply path is open to the bottom flat surface of the rotor, and the gas supply path is opened at the bottom flat surface of the rotor. Furthermore, the operation becomes easy because fine bubbles can be discharged into the liquid simply by supplying gas from the gas supply path while rotating the rotary body for making bubbles fine. Furthermore, according to the second to fourth inventions, the miniaturization and uniformity of the discharged bubbles is further promoted.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention, FIG. 2 is a vertical sectional view showing another embodiment of the rotary body for bubble refinement, and FIG.
Figures 4 and 4 show still another embodiment of the rotating body for bubble refinement, with Figure 3 being a vertical sectional view, Figure 4 being a bottom view, and Figure 5 being a bottom view.
The figures and FIG. 6 show still another embodiment of the rotating body for bubble refinement, with FIG. 5 being a vertical sectional view and FIG. 6 being a bottom view. 1...Liquid tank, 2...Hollow rotating shaft, 3,
13, 23, 33...Rotating body for bubble refinement, 7
... Gas supply path, 14 ... Recess, 24
...Groove, 34...Recess, 35...
··groove.

Claims (1)

[Scope of Claims] 1. A liquid tank 1, a vertical hollow rotating shaft 2, and a bubble attached to the lower end of the rotating shaft 2 and arranged below the liquid surface at a predetermined distance from the bottom of the liquid tank 1. It consists of a rotating body 3 for miniaturization,
The hollow part of the hollow rotating shaft 2 is a gas supply path 7, the bottom of the rotating body 3 is a flat surface, and the lower end of the gas supply path 7 is open to the bottom flat surface of the rotating body 3. Microbubble release device. 2. A liquid tank 1, a vertical hollow rotating shaft 2, and a rotating body 13 for bubble miniaturization that is attached to the lower end of the rotating shaft 2 and arranged below the liquid surface at a predetermined distance from the bottom of the liquid tank 1. The hollow part of the hollow rotating shaft 2 is made into a gas supply path 7,
The bottom of the rotating body 13 is a flat surface, a recess 14 is provided in the center of the flat surface, and the lower end of the gas supply path 7 opens into the recess 14. Minimization of air bubbles in the liquid. Emission device. 3. A liquid tank 1, a vertical hollow rotating shaft 2, and a rotating body 23 for bubble miniaturization, which is attached to the lower end of the rotating shaft 2 and arranged below the liquid surface at a predetermined distance from the bottom of the liquid tank 1. The hollow part of the hollow rotating shaft 2 is made into a gas supply path 7,
The bottom of the rotating body 23 is a flat surface, and the lower end of the gas supply path 7 is opened to the bottom flat surface of the rotating body 23.
3, a plurality of grooves 2 extending from the opening of the supply path 7 to the periphery
4 is provided radially in a liquid for atomizing and emitting bubbles. 4 A liquid tank 1, a vertical hollow rotating shaft 2, and a rotating body 33 for bubble miniaturization that is attached to the lower end of the rotating shaft 2 and arranged below the liquid surface at a predetermined distance from the bottom of the liquid tank 1. The hollow part of the hollow rotating shaft 2 is made into a gas supply path 7,
The bottom of the rotating body 33 is a flat surface, and a recess 34 is provided in the center of this flat surface, and a plurality of grooves 35 are provided extending from the recess 34 to the periphery. A device for atomizing and releasing air bubbles in a liquid that opens into a recess 34.