JPS6241058B2 - - Google Patents

Description

[Detailed description of the invention] The present invention completely separates the gas pumping side and the liquid tank,
This invention relates to an aeration device that sends appropriate bubbles into liquid.

In general, current diffusers either have a porous material that connects the gas pumping side and the liquid tank, and the gas is pumped through the porous material, or a compressor directly sends the gas into the liquid through a pipe. have. For those with a shape that pumps gas through a porous body, sawdust and silica stone are used as the porous body.
A porous body obtained by sintering a mixed molded body of river sand or alundum at high heat is used, and other commonly found materials include glass sintered bodies and acrylonitrile styrene foam. is made of a single hydrophilic material, so when the gas pumping is stopped, the liquid at the top of the porous body will penetrate into the porous body. It was necessary to devise measures to prevent this from occurring, and even with these measures, problems still arose. In addition, a configuration in which gas is sent directly through a pipe has the drawback that the bubble diameter is large and the bubbles are not dispersed uniformly in the liquid.Also, in order to prevent the liquid from penetrating into the gas pumping side through the pipe, the liquid tank and the gas pumping side must be separated. This results in an unsightly shape for the device.

In order to solve these conventional drawbacks, we have found that it is possible to use a porous body made of a water-repellent material having a pore size that does not allow water to penetrate, as previously described in Utility Model Application No. 104246/1983.

It was excellent in terms of the effect of preventing liquid penetration into the upper part of the porous body. However, due to its water repellency, there is a limit to how small the diameter of the bubbles that are removed from the liquid may be, and therefore its applications are limited. Generally speaking, in a diffuser, the bubble diameter is as small as possible, and the larger the number of bubbles, the more desirable it is in many cases.

In order to improve these shortcomings, a special application was filed in 1974.
116452, a porous body made of a hydrophilic material is coated with a water-repellent material over the entire surface or only one side. However, if the coating is incomplete, However, if there is even one spot, that part will not have water repellency, so the liquid will leak and the intended effect will not be achieved at all.

In addition, there are a wide variety of types of water-philic materials, and even in porous bodies with the same pore size, the diameters of bubbles generated vary depending on the material. The present invention solves these conventional drawbacks; in other words, the gas pumping side and the liquid tank are completely separated, completely preventing liquid from penetrating into the gas pumping side, and the liquid tank and the gas pumping side are integrated. This is an aeration device that can reduce the diameter of bubbles generated in the liquid to a sufficiently small size, or generate a necessary and sufficient amount of bubbles of any diameter.

As a result of intensive searches for porous materials in order to create the ideal air diffuser described above, the present inventors found that a surface with affinity for the liquid on the liquid tank side, ideally the solubility parameter (=SP) of the liquid We have found that it is sufficient to use a porous body with a structure in which a surface is coated with a substance having an SP value close to , and a surface exhibiting water repellency on the gas pumping side. In other words, by adopting the structure of the present invention in which the gas pumping side is made of a water-repellent porous material, one of the drawbacks of Japanese Patent Application No. 116452/1986 can be completely solved, and the SP value close to that of the liquid can be achieved. Even if the coating of the substance having the above-mentioned properties is incomplete in one place, it will not cause any essential problem since only a few bubbles in the corresponding part will become large. Furthermore, the most important factors that determine the diameter of the bubbles are the material and pore diameter of the porous body facing the liquid tank side. Among the bubble diameter controls, making them fine is the most difficult, and in order to make them fine, the solubility parameter (=
SP) Unit: (cal/cc) We discovered that it is sufficient to select a material with an SP value close to 1/2 and reduce the pore diameter of the porous material. By coating with a material whose SP value is close to that of the liquid, it has become possible to easily change the size of bubbles from minute to large by simply changing the pore size. As an example of an aeration device using water as a liquid, polyvinyl alcohol, cellulose acetate, etc. having an SP value close to that of water may be selected.

The present invention has made it possible to create an ideal air diffuser for the first time.

The present invention will be explained in more detail below.

The structure of the porous body is not the entire surface of the porous body made of water-repellent material, but the surface facing the liquid tank is the SP of the liquid.
A structure coated with a substance having an SP value close to the SP value is suitable for the present invention.

The water-repellent porous material here refers to fluororesin,
It means a porous body made of silicone resin, rubber, polyethylene, polypropylene, etc., or a combination of these water-repellent materials. Among these, porous fluororesin materials are excellent in terms of water repellency. Fluororesins include trifluorochloroethylene resin, vinylidene fluoride resin, tetrafluoroethylene resin, and
It refers to these copolymers, etc., and among them, tetrafluoroethylene resin can be said to be representative of fluororesins.

It is sufficient that the water-repellent porous body used has a pore size that does not allow liquid to penetrate. Regarding the more desirable properties of the porous body, the pore diameter is 5 to 50 μm, the porosity is preferably in the range of 50 to 95%, and the thickness is 0.1 to 95% in terms of strength.
Preferably 10mm.

The structure of the porous body is preferably a nonwoven fabric structure in which fibers are laminated, or a structure having a fine fiber structure consisting of nodules interconnected by fibers. One example of the latter manufacturing method is a method in which a fluororesin is formed into a sheet by extrusion and rolling, then stretched in at least one direction, and then sintered. This manufacturing method makes the above structure possible.

Among them, a porous material with a non-woven structure made by laminating fibers, for example, a thickness of fibers of 0.01 to 3 deniers.
A nonwoven fabric with a size of 0.1 to 2.0 mm and a porosity of 50 to 95% is optimal in terms of breathability, ease of handling, and resistance to clogging due to foreign matter carried from the gas pumping side. In use, it is wise to pay close attention to foreign matter brought in from the gas pumping side. To prevent this clogging, a breathable foam or nonwoven fabric may be used on the water-repellent surface, that is, on the gas pumping side. The air diffuser according to the present invention can be used for any purpose as long as it disperses air bubbles uniformly in a liquid. It can be used as a device to destroy and remove fat and dirt from instruments, machinery, etc.

The basic structure of a facial cleansing device, which is one of the uses as a conventional cleaning device, is that the top plate is made of a bubble generating plate made of a porous material, and the main body of the bubble generating device, which has a bag-shaped air pocket formed inside, is placed inside the facial cleansing device. The device is configured so that air is forced into the bubble generator body through an air pipe to generate a large number of bubbles in the water inside the face wash, and the ultrasonic waves generated by the bursting of the bubbles have an excellent face cleansing effect. It is something. but,
There is the problem of liquid penetration mentioned earlier, so it is not perfect yet.

By using the air diffuser of the present invention, the drawbacks can be compensated for without sacrificing the advantages, resulting in a more complete facial cleansing device. Conventional facial cleansers have been designed to prevent water from penetrating.
In order to guide the air pipe, a part of the air pipe is set at a position higher than the water level of the face wash on the way to the air pressure supply side, or a valve is installed that opens and closes when the air pressure supply starts and stops. .

The present invention eliminates the need for such valves and water drain ports provided between the porous body and the ventilation side, making the structure extremely simple.

It can also be used as an air diffuser integrated with a fish tank. It is also effective as an aeration device and gas-liquid reaction device in activated sludge method. Finally, an example of the present invention is shown in the figure. However, it is not limited to this.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a face washing device, Fig. 2 is a schematic diagram of an air diffuser used in a bathtub, and Fig. 3 is a schematic diagram of the porous bodies 4 and 11 used in Figs. 1 and 2. It is an enlarged schematic diagram. 1...Face wash tank, 2...Water, 3...Porous body presser, 4
... Porous body, 5... Polypropylene nonwoven fabric, 6... Pump built-in part, 7... Textile cloth, 8... Bathtub, 9... Water, 1
0... Stainless steel punching plate, 11... Porous body,
12...Glass nonwoven fabric, 13...Air pocket, 14
... Air pipe, 15... Pump, a... Polyvinyl alcohol coating layer, b... Tetrafluoroethylene resin porous body.

Claims (1)

[Scope of Claims] 1 The gas pumping side and the liquid tank are partitioned through a porous body, and the gas sent from the gas pumping side passes through the porous body to form air bubbles and diffused air that is generated in the liquid. In the device, a porous body made of a water-repellent material is used as the porous body, and the surface of the porous body on the liquid tank side is coated with a substance that has an affinity for the liquid, excluding the liquid tank side surface of the porous body. An air diffuser characterized in that a portion remains water repellent. 2. The air diffuser according to claim 1, wherein the substance having an affinity for the liquid has an SP value close to the solubility parameter (=SP) of the liquid. 3. The air diffuser according to claim 1, wherein the porous water-repellent material is a porous fluororesin material. 4 Claim 3, characterized in that the fluororesin porous body is a tetrafluoroethylene resin porous body
Air diffuser as described in section. 5. The air diffuser according to claim 1, wherein the porous body of water-repellent material has a pore size that does not allow liquid to penetrate. 6 Porous body has a porosity of 50-95% and a pore size of 5-50μ
2. The air diffuser according to claim 1, wherein the air diffuser has a characteristic of having a thickness of 0.1 to 10 mm. 7. The air diffuser according to claim 1, wherein the porous body has a non-woven structure made of laminated fibers. 8. The air diffuser according to claim 1, wherein the porous body has a fine fiber structure consisting of nodules interconnected by fibers. 9. The air diffuser according to claim 1, characterized in that a clogging prevention mechanism is provided on the water-repellent surface. 10. The air diffuser according to claim 9, characterized in that a breathable foam is used as the clogging prevention mechanism. 11. The air diffuser according to claim 9, characterized in that a nonwoven fabric is used as the clogging prevention mechanism. 12 Bubbles generated in the liquid through the porous body,
The air diffuser according to claim 1, wherein the air diffuser is used as a cleaning device for cleaning an object placed in a liquid. 13 Air bubbles generated in the liquid through the porous body,
The air diffuser according to claim 1, which is used as an air diffuser for a fish tank because of its effect of increasing the oxygen content in the liquid. 14. The aeration device according to claim 1, which is used as an aeration device for culturing aerobic bacteria in an activated sludge method, which is a method of sewage treatment. 15. The air diffuser according to claim 1, which is used as an air diffuser for efficiently reacting gas and liquid.