JP2012217895A - Defoaming apparatus of foam and defoaming treatment method of foam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To promptly defoam foam without using a defoaming agent.SOLUTION: The defoaming apparatus has an inner tank, an outer tank housing the inner tank and a rotation mechanism for rotating the inner tank. The inner tank is constituted of an inner tank opening for supplying foam at its upper part, an inner tank bottom for holding the foam at its lower part and a side wall formed of a porous water-repellent cylinder which is made of a material that does not become completely wet with a solution constituting the foam to be treated and which has pores where liquid produced by foam breaking can pass. The outer tank has an outer tank opening for supplying foam at its upper part, a withdrawal port which is provided at an outer tank bottom and which sends liquid produced by foam breaking to a next step and a side wall for preventing the liquid from being scattered outside. The defoaming apparatus is characterized by providing a space between an outer wall of the inner tank bottom and an inner wall of an outer tank bottom so that a solution produced by foam breaking and liquifying due to rotation of the inner tank may gather at the outer tank bottom and may not be agitated.

Description

  The present invention relates to a foam defoaming apparatus and a foam defoaming method.

  The foam generated in the treatment liquid needs to be effectively eliminated. For example, in Patent Document 1, an inner tank to which bubbles of the processing liquid are supplied, a plurality of blade members fixed to the inner wall of the inner tank, a motor for rotating the inner tank, and a concentric circle of the inner tank are arranged. And an outer tank that collects the processing liquid that has passed through a plurality of small-diameter holes, and a defoaming device that breaks and liquefies bubbles by centrifugal force applied by rotation of the inner tank is described.

JP 2000-254408 A

  Many foams are present in general washing waste liquids. In addition, foam may be included in the processing liquid after a flat display substrate such as a printed wiring board or a liquid crystal panel is subjected to processing such as development, cleaning, or peeling by a wet process. In the case of flotation, separation is performed by adsorbing particles to the foam of a solution containing a surfactant. It is advantageous if the particles can be recovered simultaneously with defoaming.

There is also a technique of foaming a plating solution and performing plating in a flowing foam. These foams may then be treated as waste liquid, and the recovered foams may be made into solution and reused. An antifoaming agent such as silicone oil is often used to quickly defoam the foam. However, the use of an antifoaming agent adds unnecessary components to the defoamed solution in the subsequent process. In this case, it is difficult to reuse the collected solution, and an extra load is imposed on the waste liquid treatment.
An object of the present invention is to quickly defoam a foam without using an antifoaming agent.

Hereinafter, the inventions according to [1] to [10] are provided.
[1] The invention according to claim 1 is an antifoaming device having an inner tub, an outer tub that accommodates the inner tub, and a rotating mechanism that rotates the inner tub. The inner tank opening for supplying the foam, the inner tank bottom holding the foam at the bottom, and the solution that makes up the foam to be processed are made of a material that does not completely wet and the liquid generated by the bubble breakthrough passes. A side wall made of a porous water-repellent cylinder having pores, and the outer tub is provided at the bottom of the outer tub for supplying foam to the upper part and the bottom of the outer tub, and the foam is generated by bubble breakage. An outlet for sending the liquid to the next step, and a side wall for preventing the liquid from splashing to the outside, and the inner tank between the outer wall of the inner tank bottom and the inner wall of the outer tank bottom The solution broken and liquefied by the rotation of the water collected at the bottom of the outer tank is not stirred. Antifoaming apparatus characterized in that a space like.

[2] The invention according to claim 2 is an antifoaming device having an inner tub, an outer tub that accommodates the inner tub, and a rotating mechanism that rotates the inner tub. The opening, the bottom of the inner tank, the cylindrical side wall having holes or slits through which the liquid produced by the foam to be treated can freely pass, and the solution that is arranged inside the side wall and constitutes the foam to be treated are completely A cylindrical porous water-repellent sheet made of a non-wetting material, and the outer tub is an outer tub opening for supplying foam to the upper part, and the foam is generated by bubble breakage at the bottom of the outer tub An outlet for sending the liquid to the next process, and a side wall for preventing the liquid from splashing to the outside, and between the outer wall of the inner tank bottom and the inner wall of the outer tank bottom, The solution broken and liquefied by the rotation of the tank accumulates at the bottom of the outer tank and is stirred. Antifoaming apparatus characterized in that a space so as not to.

[3] The invention according to claim 3 is characterized in that particles made of a water-repellent material are filled in the side wall made of the porous water-repellent cylinder or the inside of the cylindrical porous water-repellent sheet. Or it is an antifoaming apparatus of 2.
[4] The invention according to claim 4 is characterized in that the side wall or cylinder made of at least one porous water-repellent cylinder is further provided inside the side wall made of the porous water-repellent cylinder or the inside of the cylindrical porous water-repellent sheet. The antifoaming device according to any one of claims 1 to 3, wherein a porous water-repellent sheet is provided.
[5] In the invention according to claim 5, particles made of a water-repellent material are filled in an arbitrary space between a side wall made of a plurality of the porous water-repellent cylinders or a plurality of the cylindrical porous water-repellent sheets. The defoaming device according to claim 4, wherein the defoaming device is provided.
[6] The invention according to claim 6 is characterized in that a filter is provided inside the side wall made of the porous water-repellent cylinder or between the cylindrical side wall having a hole or a slit and the cylindrical porous water-repellent sheet. The antifoaming device according to any one of claims 1 to 5, wherein the defoaming device is arranged.

[7] The invention according to claim 7 is a foam defoaming method, wherein a foam is brought into contact with a porous sheet or cylinder made of a water-repellent material in a rotating rotating tank to make a defoamed solution. Foam defoaming, comprising: a defoaming step; and a recovery step of allowing the solution produced by the defoaming step to pass through the porous sheet by centrifugal force of the rotating tank and recovering the solution It is a processing method.
[8] The foam defoaming method according to claim 7, wherein in the collecting step, the solution that has permeated the porous sheet is further permeated through a filter. is there.
[9] The invention according to claim 9 is characterized in that, in the recovery step, the solution that has passed through a plurality of gaps provided on a side surface of the rotating tub containing the porous sheet is recovered. Or the foam defoaming treatment method according to 8.
[10] In the invention according to claim 10, when the outer radius of the rotating tub is expressed in cm, the rotating speed of the rotating tub is 393 × (the inverse of the square root of the radius of the rotating tub) rpm or more. The foam defoaming method according to any one of claims 7 to 9, wherein the foam is defoamed.

  According to the present invention, foam can be quickly removed without using an antifoaming agent.

It is a figure explaining an example of the defoaming apparatus with which this Embodiment is applied. It is a cross-sectional top view of the defoaming apparatus shown in FIG. It is a cross-sectional top view explaining the defoaming apparatus provided with the filter. It is a figure explaining another example of a defoaming apparatus.

  Hereinafter, embodiments of the present invention will be described in detail. In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary. Further, the drawings used are used for explaining the present embodiment and do not represent actual sizes and shapes.

<Defoaming device>
FIG. 1 is a diagram illustrating an example of a defoaming device to which the present embodiment is applied. The defoaming device 30 shown in FIG. 1 includes an inner tub 31 as a rotating tub that accommodates the foam 11 generated by a predetermined process, and an outer tub 32 in which the inner tub 31 is rotatably attached by a rotation shaft 35. ing. Further, a cylindrical porous water-repellent sheet 33 as a porous sheet is disposed inside the inner tank 31. Further, at the lower part of the outer tub 32, a discharge port 34 is provided as an extraction port for discharging the processing liquid 11b after the defoaming process.

(Inner tank 31)
The inner tank 31 has an inner tank opening 31a for supplying the foam 11 at the upper part, a bottom face 31b for holding the foam 11 at the lower part, and a cylindrical side wall 31c. A plurality of slits 311 through which the liquid generated by the foam to be processed can freely pass is formed in the side wall 31c. In place of the slit 311, a plurality of holes such as a rectangle, a rectangle, a circle, and a net may be formed. Inside the side wall 31c, a cylindrical porous water-repellent sheet 33 made of a material that is not completely wetted by the solution constituting the foam to be treated is disposed. The inner tank 31 is a rotating tank that is rotatably attached to the outer tank bottom 32b of the outer tank 32 by a rotation shaft 35 and is rotated by a predetermined rotating mechanism (not shown). Although FIG. 1 shows an example in which the rotating mechanism is placed in the lower part of the rotating tank, the rotating mechanism may be in the upper part of the rotating tank.

As described in the previous section, the slit 311 formed in the side wall 31c of the inner tank 31 may be a plurality of holes or nets such as a rectangle, a rectangle, and a circle, and the shape and size thereof are not particularly limited. It is necessary that the porous water-repellent sheet 33 can be stably held when the tank 31 rotates. In the present embodiment, the slit 311 has a vertically long shape, and the width is usually 10 mm or less, preferably 7 mm or less, depending on the material of the inner tank. However, it is usually 0.5 mm or more, preferably 1 mm or more.
The material which comprises the side wall 31c is not specifically limited, For example, a plastic, a metal, etc. are mentioned.

(Outer tank 32)
The outer tub 32 is composed of an outer tub bottom 32b and a side wall 32c that prevents the liquid generated by the foam 11 from breaking off from splashing to the outside, and between the side wall 31c of the inner tub 31 and the side wall 32c of the outer tub 32. Is provided with a gap 32a through which the liquid captured by the side wall 32c of the outer tub 32 flows downward. The outer tank bottom 32b is provided with a discharge port 34 as an extraction port through which the liquid produced by the foam 11 breaking is sent to the next step. Between the uppermost part of the side wall 32c and the inner tank opening 31a for supplying the foam 11, although not shown, a lid is provided to prevent the splashes from scattering.

  In addition, the outer tank bottom of the outer tank 32 is a solution that is broken and liquefied by the rotation of the inner tank 31 between the outer wall of the inner tank bottom 31b of the inner tank 31 and the inner wall of the outer tank bottom 32b of the outer tank 32. A space is provided so as not to stir and stir in 32b.

(Porous water-repellent sheet 33)
The porous water-repellent sheet 33 has a cylindrical shape so as to be in contact with the inner wall of the inner tub 31, and is formed of a porous water-repellent material. Here, the water repellent material means a material that is not completely wetted with the solution constituting the foam 11 to be treated. Specifically, it is a material whose contact angle with respect to the solution which forms a to-be-processed foam is not 0, More preferably, it is a material whose contact angle is 90 degrees or more. Examples of materials that can be used include fluororesins and polyolefins.

The porous structure of the porous water-repellent sheet 33 is not particularly limited. For example, a structure in which a plurality of through holes having a predetermined hole diameter are formed, a structure in which a plurality of vertically long holes or horizontally long holes are formed, a network structure, etc. Is mentioned. Further, for example, a porous material such as a nonwoven fabric can be used.
The size of the plurality of through-holes possessed by the porous structure is usually 20 times or less the diameter of the foam to be treated, more preferably 10 times or less the size of the size representing the shape of the through-hole. It is. In the present embodiment, the pore diameter of the plurality of through holes of the porous structure is usually 1.5 mm or less, preferably 1 mm or less. However, it is usually 1 μm or more, preferably 3 μm or more.

  In the present embodiment, a cylindrical water-repellent sheet formed of a porous water-repellent material similar to the porous water-repellent sheet 33 is provided inside the porous water-repellent sheet 33 to form a multilayer structure. Is possible. Of the sizes representing the shape of the pores of the porous water-repellent sheet 33, the size of the small one representing the shape of the pores of the porous water-repellent sheet 33 is smaller than the size representing the shape of the pores of the porous water-repellent sheet 33. It may be several times larger than the size.

  In this case, further, particles made of a water repellent material can be filled in an arbitrary space between the porous water repellent sheet 33 and the plurality of cylindrical water repellent sheets. Examples of the material of the particles made of the water repellent material include a fluororesin and a polyolefin. The particles do not need to have a specific shape and are arbitrary, and the size thereof may be any size as long as it does not pass through the holes of the porous water-repellent sheet 33, and is usually in the range of 1 mm to 10 mm.

  As described above, the inner tank 31 is rotatably attached to the outer tank 32 by a rotation mechanism (not shown). The rotation speed of the inner tank 31 is not particularly limited. In the present embodiment, when the outer radius of the inner tank 31 that is a rotating tank is expressed in cm, the rotational speed of the inner tank 31 is 393 × (the reciprocal of the square root of the radius of the inner tank 31) rpm or more and 3 000 × (the reciprocal of the square root of the radius of the inner tank 31) is preferably in the range of about rpm.

  2 is a cross-sectional plan view taken along the line II-II of the defoaming apparatus shown in FIG. As shown in FIG. 2, the foam 11 breaks the fine foam 11 on the surface of the porous water-repellent sheet 33 and returns to the liquid state. Thereafter, the solution that has returned to the liquid state passes through the porous water-repellent sheet 33, and further passes through the slit 311 formed on the side surface of the inner tank 31 that rotates in the direction of the arrow A by the rotation shaft 35. To reach.

FIG. 3 is a cross-sectional plan view illustrating a defoaming device provided with a filter.
The defoaming device shown in FIG. 3 further has a filter 36 provided between the porous water-repellent sheet 33 and the inner tank 31. The solution that has returned to the liquid state after foam breaking on the surface of the porous water-repellent sheet 33 passes through the porous water-repellent sheet 33, further passes through the filter 36, and passes through the side surface of the inner tank 31 through the slit 311. The outer tank 32 is reached.

By providing the filter 36 between the porous water-repellent sheet 33 and the side wall 31c (see FIG. 1) of the inner tank 31, the particulate solids contained in the solution are filtered at the same time as the foam 11 disappears. be able to.
The filter 36 is made of a material that is not eroded by the solution and is not particularly limited. In the present embodiment, for example, paper, various felts, and the like can be given. The pore diameter of the filter 36 is appropriately selected according to the size of the particles to be filtered. In the present embodiment, the pore diameter of the filter 36 is usually 250 μm or less, preferably 100 μm or less, and usually 0.3 μm or more, preferably 0.7 μm or more.

<Defoaming method for foam>
The foam 11 transferred to the defoaming device 30 comes into contact with the porous water-repellent sheet 33 disposed inside the side wall 31c of the inner tub 31 by the centrifugal force generated by the rotation of the inner tub 31 of the defoaming device 30, and the porous Defoaming is performed on the surface of the water-repellent sheet 33.
In the present embodiment, the foam 11 discharged to the inner tank 31 comes into contact with the surface of the porous water-repellent sheet 33 by a centrifugal force generated by the rotation of the inner tank 31. It is considered that the plurality of fine bubbles constituting the foam 11 are combined and broken by the action of the water repellent material.

The foam 11 passes through the porous water-repellent sheet 33 after the foam 11 breaks on the surface of the porous water-repellent sheet 33, and further passes through the slit 311 formed on the side surface of the inner tank 31. It is discharged from a discharge port 34 provided at the bottom of 32.
The solution discharged from the outer tank 32 is recovered by a predetermined recovery device (not shown). During the collection process, the collected solution can be further permeated through a filter.

<Another example of defoaming device>
FIG. 4 is a diagram for explaining another example of the defoaming apparatus. The same code | symbol is used for the structure similar to the defoaming apparatus 30 shown in FIG. 1, and the description is abbreviate | omitted.
The defoaming device 300 shown in FIG. 4 includes an inner tub 301 as a rotating tub and an outer tub 32 in which the inner tub 301 is rotatably attached by a rotation shaft 35. In the lower part of the outer tub 32, a discharge port 34 is provided as an extraction port for discharging the processing liquid 11b after the defoaming process.

(Inner tank 301)
The inner tank 301 has an opening 301a, an inner tank bottom 301b, and a cylindrical side wall 301c. The side wall 301c is made of a material similar to the porous water-repellent sheet 33 (see FIG. 1) used in the defoaming device 30 described above (that is, a material that is not completely wetted with the solution constituting the foam 11 to be treated). The porous water-repellent cylinder is formed and has a plurality of holes through which liquid generated by bubble breaking can pass.
The porous structure of the side wall 301c is not particularly limited, and similarly to the porous water-repellent sheet 33 described above, for example, a structure in which a plurality of through holes having a predetermined hole diameter are formed, a plurality of vertically long holes or horizontally long holes are formed. And a reticulated structure. Further, for example, a porous material such as a nonwoven fabric can be used.

A defoaming apparatus 300 shown in FIG. 4 is provided with a cylindrical water-repellent sheet formed of a porous water-repellent material similar to the porous water-repellent cylinder inside a side wall 301c made of a porous water-repellent cylinder. A multilayer structure is also possible.
In this case, further, particles made of a water repellent material can be filled in an arbitrary space between the side wall 301c and the cylindrical water repellent sheet or between the plurality of cylindrical water repellent sheets. .

  Further, by providing a filter inside the side wall 301c made of a porous water-repellent cylinder, particulate solids contained in the solution can be filtered at the same time as the foam 11 disappears.

DESCRIPTION OF SYMBOLS 11 ... Foam, 30,300 ... Defoaming device, 31, 301 ... Inner tank, 32 ... Outer tank, 33 ... Water-repellent porous sheet, 34 ... Discharge port

Claims (10)

An antifoaming device having an inner tank, an outer tank that houses the inner tank, and a rotating mechanism that rotates the inner tank,
The inner tank is
The inner tank opening for supplying foam to the upper part, the inner tank bottom part for holding the foam at the lower part, and the solution that constitutes the foam to be processed are made of a material that is not completely wetted, and the liquid generated by the bubble breakage A side wall made of a porous water-repellent cylinder having pores that can pass through,
The outer tank is
Outer tub opening for supplying foam to the upper part, outlet provided for the bottom of the outer tub to supply the liquid produced by the foam breakage to the next step, and side walls to prevent the liquid from splashing to the outside And having
A space is provided between the outer wall of the inner tank bottom and the inner wall of the outer tank bottom so that the solution broken and liquefied by the rotation of the inner tank accumulates at the bottom of the outer tank and is not stirred. Defoaming device characterized. An antifoaming device having an inner tank, an outer tank that houses the inner tank, and a rotating mechanism that rotates the inner tank,
The inner tank is
The inner tank opening, the inner tank bottom, the cylindrical side wall having holes or slits through which the liquid produced by the foam to be treated can freely pass, and the solution that is disposed inside the side wall and constitutes the foam to be treated are completely It consists of a cylindrical porous water-repellent sheet made of a material that does not wet,
The outer tank is
Outer tank opening for supplying foam to the upper part, outlet port for sending the liquid generated by the foam breakage to the outer tank bottom to the next step, a side wall for preventing the liquid from splashing to the outside, Have
A space is provided between the outer wall of the inner tank bottom and the inner wall of the outer tank bottom so that the solution broken and liquefied by the rotation of the inner tank accumulates at the bottom of the outer tank and is not stirred. Defoaming device characterized.   The defoaming device according to claim 1 or 2, wherein particles made of a water-repellent material are filled in a side wall made of the porous water-repellent cylinder or the inside of the cylindrical porous water-repellent sheet.   A side wall made of at least one porous water-repellent cylinder or a cylindrical porous water-repellent sheet was further provided inside the side wall made of the porous water-repellent cylinder or the inside of the cylindrical porous water-repellent sheet. The defoaming apparatus according to any one of claims 1 to 3, wherein   The side wall made of a plurality of the porous water-repellent cylinders or an arbitrary space between the plurality of cylindrical porous water-repellent sheets is filled with particles made of a water-repellent material. Defoaming device.   2. A filter is disposed inside a side wall made of the porous water-repellent cylinder, or between the cylindrical side wall having a hole or a slit and the cylindrical porous water-repellent sheet. 6. The defoaming device according to any one of items 5 to 5. A foam defoaming method, comprising:
A defoaming step for defoaming the solution by bringing the foam into contact with a porous sheet or cylinder made of a water-repellent material in a rotating rotating tank;
A recovery step of allowing the solution produced by the defoaming step to pass through the porous sheet by a centrifugal force of the rotating tank and recovering the solution;
A foam defoaming method characterized by comprising:   The foam defoaming method according to claim 7, wherein in the recovery step, the solution that has permeated the porous sheet is further permeated through a filter.   The foam defoaming method according to claim 7 or 8, wherein, in the recovery step, the solution that has passed through a plurality of gaps provided on a side surface of the rotary tank containing the porous sheet is recovered. .   10. The rotation speed of the rotary tank is 393 × (reciprocal of the square root of the radius of the rotary tank) rpm or more when the outer radius of the rotary tank is expressed in cm. The foam defoaming method according to claim 1.

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