JPH09805A - Defoaming method and apparatus - Google Patents

Abstract

PURPOSE: To break foams to convert them to an original liquid body without using chemicals and water. CONSTITUTION: Once a foam 10 is frozen and then the foam 10 is heated or crushed. When the liquid portion 11 of the foam 10 is frozen, cracks 14 are formed in the portion of the solid body 13, that is a husk. Consequently, a gas 12 in the husk is discharged forcibly during the heating process. Discharge of the gas 12 is accelerated also by crushing the frozen foam 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a defoaming method and apparatus for destroying bubbles generated from various liquids and returning them to the original liquids.

[0002]

2. Description of the Related Art Recently, a coating method has been developed in which a coating material is mixed with a special liquid, stirred and foamed, and then the foam is brought into contact with the surface of a steel plate or the like. In this method, the coating that covers the surface of the foam of the special liquid is transferred to the surface of the steel plate, etc., but since the foam of the special liquid is used as a transport medium for the paint, it is consumed even when painting. It will not be done. Therefore, this coating method produces a large number of bubbles.

Therefore, in this coating method, a defoaming technique for sequentially destroying the generated bubbles and returning them to the original liquid is indispensable from the viewpoint of reducing the processing space and reusing the liquid. In addition, eliminating bubbles in chemical factories is an important issue.

Conventionally, as a method of eliminating bubbles, a method of using an antifoaming chemical or washing with a large amount of water has been adopted.

[0005]

However, when an antifoaming chemical is used, the composition of the liquid changes. In addition, the concentration changes when washed off with water. Therefore, the liquid cannot be reused by any of the methods. There is also a risk of causing pollution problems.

The present invention was devised in view of such circumstances, and by physically destroying bubbles generated from a liquid, it is possible to efficiently restore the original liquid without changing the components and the concentration. It is an object to provide a defoaming method and device.

[0007]

In the defoaming method according to the present invention, a foam is once frozen and then the foam is heated or crushed.

A first defoaming device according to the present invention comprises a container for containing foam, a refrigerator for cooling the container to freeze the foam in the container, and a container for heating the container to liquidize the frozen foam in the container. And a heater for returning to.

A second defoaming device according to the present invention is a carrier line for continuously carrying foam, a refrigerator arranged in the carrier line for freezing foam carried in the line, and a freezer in the carrier line. And a heater which is arranged on the further downstream side and which heats the frozen foam to return it to a liquid.

A third defoaming device according to the present invention is a carrier line for continuously carrying foam, a refrigerator arranged in the carrier line for freezing foam carried in the line, and a freezer in the carrier line. And a crusher which is arranged on the further downstream side and crushes frozen foam.

In the second defoaming device and the third defoaming device, a tank for accumulating the liquid obtained from the foam and a return line for returning the foam accumulated on the liquid in the tank to the upstream side of the refrigerator. It is desirable to provide it.

[0012]

The principle of defoaming in the present invention is shown in FIG. Generally, the bubble 10 has a structure in which a thin film of a liquid 11 covers a gas 12 such as air. Since this is a phenomenon caused by the surface tension of the liquid, the bubble 10 is often spherical.

When a portion of the liquid 11 of the bubble 10, that is, a thin film of the liquid 11 is frozen, the thin film becomes a shell of the solid 13, and at the same time, many cracks 14 are formed in the shell.
Here, when the shell is heated, the shell 12 is melted, and at the same time, the gas 12 in the shell is expanded and discharged to the outside of the nucleus. Moreover, even if the shell is crushed, the gas in the shell is discharged. After crushing, thaw the shattered shell naturally or forcibly. In either case, the gas 12 in the shell escapes, leaving only the liquid 11 portion. The remaining liquid 11 may contain the gas 12, but the amount thereof is very small.

Thus, without using chemicals or water,
Most of the bubbles 10 generated from the liquid are the original liquid 11 efficiently.
Return to the state of. This is the same principle that no bubbles remain when the soft serve ice cream melts.

Among the crushing, crushing with a roll or the like has a particularly high effect of promoting discharge of gas in the shell. After crushing, either natural thawing or heat thawing may be performed, but heat thawing increases the processing efficiency.

Further, it is possible to improve the treatment efficiency by freezing and thawing the foam remaining after thawing again.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows a first defoaming device 1 according to the present invention.
FIG. 3 is a schematic diagram showing an example, FIG. 3 is a schematic diagram showing an example of a second defoaming device according to the present invention, and FIG. 4 is a schematic diagram showing an example of a third defoaming device according to the present invention. Both defoaming devices
The defoaming method according to the present invention can be efficiently carried out.

The defoaming device shown in FIG. 2 comprises a container 2 for containing the foam 1, a box-shaped refrigerator 3 for housing the container 2, and a box-shaped heater 4 for housing the container 2 as well. To have. The refrigerator 3 cools the contained container 2 to freeze the foam 1 in the container 2. The heater 4 heats the contained container 2 to thaw the foam 1 frozen in the container 2.

After the foam 1 is contained in the container 2, the container 2 is put in the refrigerator 3 and cooled. When the foam 1 in the container 2 freezes, the container 2 is transferred to the heater 4 and the foam 1 in the container 2 is thawed. Each bubble is cracked in the process of freezing, and the discharge of gas in the bubble is promoted in the process of heating and thawing, whereby the foam 1 returns to the original liquid 11. The amount of the foam 1 left on the liquid 11 is small.

In order to avoid the transfer of the container 2, one box may have a cooling function and a heating function.

The cooling temperature and the cooling time for freezing the foam 1 differ depending on the type and the treatment amount of the liquid forming the foam 1, and are appropriately determined depending on the type and the treatment amount. Although shaving cream was used in the experiment, a cooling temperature of -20 ° C or lower was necessary.

The defoaming device shown in FIG. 3 comprises a silo 5 for temporarily accumulating the foam 1 continuously fed.
The foam 1 in the silo 5 is continuously conveyed by the pipe type conveyance line 7 through the tank 6a. For transporting foam 1,
In addition to gravity, gas pressure, a feed blade described later, or the like can be used.

The transport line 7 is provided with a refrigerator 3 and a heater 4 is provided downstream of the refrigerator 3. The refrigerator 3 has a configuration in which a refrigerant pipe is wound around the pipe of the transfer line 7 (see FIG. 4), and freezes the foam 1 conveyed in the pipe. Further, the heater 3 heats the pipe from the outside, freezes and heats and thaws the foam 1 carried in the pipe. As in the defoaming device shown in FIG. 2, the foam 1 efficiently returns to the original liquid 11 by freezing and subsequent thawing.

The obtained liquid 11 is stored in the tank 6b and appropriately extracted from the tank 6b.

Since the defoaming device shown in FIG. 2 is a so-called batch type, the defoaming device shown in FIG. 3 is a continuous type, so that this defoaming device is more efficient.

In the defoaming device shown in FIG. 4, the foam 1 in the tank 6a is continuously carried by a pipe-type carrying line 7 using spiral feed blades 7a. In the transfer line 7, a refrigerator 3 similar to that used in the defoaming device shown in FIG. 3 is installed.

A crusher 8 using a pair of rolls is arranged on the exit side of the transfer line 7. The crusher 8 is a foam 1 frozen by the refrigerator 3 and discharged from the transfer line 7.
Crush. The frozen foam 1 which has been finely divided by this crushing is put into the tank 6b, thawed there, and returned to the original liquid 11.

At this time, the remaining foam 1 collects on the liquid 11. The foam 1 is returned to the transport line 7 on the upstream side of the refrigerator 3 by the pipe-type return line 9 using the spiral-shaped feed blade 9a.

The liquid 11 accumulated in the tank 6b is discharged into the discharge pipe 6
It is appropriately extracted from c.

Since this defoaming device is of the same continuous type as the defoaming device shown in FIG. 3, it is highly efficient. Further, since the frozen foam 1 is crushed by the pair of crushers 8, the gas in the foam can be easily released and the efficiency is high. Furthermore, the remaining foam 1
Is returned to the transfer line 7 from the tank 6a and reprocessed, so that the efficiency is higher. Tank 6b contains untreated foam 1
Has a function of separating the liquid 11 from the liquid 11. In order to further improve the efficiency, the tank 6b may be heated to accelerate the thawing of the foam 1.

[0032]

As described above, the defoaming method and apparatus according to the present invention effectively discharge the gas in the foam by a combination of freezing and heating or freezing and crushing, and therefore it is necessary to use chemicals or water. Without, the liquid obtained from the foam can be reused. Further, since bubbles that are not destroyed even if left to stand are efficiently destroyed by heating or crushing in a short time, the processing time is short and the space for accumulating bubbles can be made small.

Second defoaming device and third embodiment according to the present invention
Since the defoaming device of No. 1 performs continuous processing, it has particularly high processing efficiency and efficiency.

In the second defoaming device and the third defoaming device, a tank for storing the liquid obtained from the foam and a return line for returning the foam accumulated on the liquid in the tank to the upstream side of the refrigerator are provided. In this case, the processing efficiency can be further improved.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing the defoaming principle in the present invention.

FIG. 2 is a schematic view showing an example of a first defoaming device according to the present invention.

FIG. 3 is a schematic view showing an example of a second defoaming device according to the present invention.

FIG. 4 is a schematic view showing an example of a third defoaming device according to the present invention.

[Explanation of symbols]

 1 Foam 2 Container 3 Refrigerator 4 Heater 5 Silo 6a, 6b Tank 7 Transfer line 8 Crusher 9 Return line 10 Foam 11 Liquid 12 Gas 13 Solid 14 Crack

Claims (5)

[Claims] 1. A method for defoaming, which comprises freezing a foam once and then heating or crushing the foam. 2. A container comprising a foam, a refrigerator for cooling the container to freeze the foam in the container, and a heater for heating the container to return the frozen foam in the container to a liquid. A characteristic defoaming device. 3. A transfer line for continuously transferring foam, a freezer arranged in the transfer line for freezing foam transferred through the line, and a transfer line downstream of the freezer in the transfer line and frozen. A defoaming device, comprising: a heater that heats foam to return it to a liquid. 4. A transport line for continuously transporting foam, a refrigerator arranged in the transport line to freeze the foam transported in the line, and a refrigerator in the transport line downstream of the freezer and frozen. A defoaming device comprising: a crusher for crushing foam. 5. The defoaming device according to claim 3 or 4, wherein a tank for storing the liquid obtained from the foam and a return line for returning the foam accumulated on the liquid in the tank to the upstream side of the refrigerator are provided. A defoaming device characterized in that