JP2016005827A - Bubble elimination device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bubble elimination device that has a simple structure and can eliminate bubbles contained in a liquid.SOLUTION: A bubble elimination device 1 includes: a container 2 in which a liquid can be put; a hollow cylindrical shaft member 3 which is disposed in the direction from the liquid surface side of the liquid put in the container 2 toward the bottom surface side of the container, and which can rotate relatively to the container 2; and an air supply device 6 which can supply the hollow part in the shaft member 3 with air. A driving device 8 relatively rotates the container 2 and the shaft member 3 to rotate the liquid put in the container 2, gathers first bubbles B1 contained in the liquid around the shaft member 3, makes the air supply device 6 supply the follow part in the shaft member 3 with air to generate second bubbles B2 from a communication passage 33 through which the inside and the outside of the shaft member 3 communicate, and makes the second bubbles B2 hit the first bubbles B1 to eliminate the first bubbles B1.

Description

  The present invention relates to a defoaming device that defoams bubbles contained in a liquid.

  In recent years, lithium ion secondary batteries have been applied to hybrid vehicles and electric vehicles. In order to obtain a slurry of the active material, the electrode of the lithium ion secondary battery is first kneaded with a powder of the active material in a solution of the thickener, and then the slurry of the active material is a base such as an aluminum foil. It is manufactured by applying to a material and drying. Since the slurry in the kneading step is stirred, air is often involved in the slurry and remains as foam. This bubble may become a pinhole in the electrode, causing a decrease in battery performance. For this reason, the foam contained in the slurry must be surely defoamed.

  In Patent Document 1, a hollow shaft having a rotating blade at one end is inserted into the liquid in the container, the rotating blade is rotated to circulate the liquid in the container on the inner and outer circumferences of the hollow shaft, Describes a device for defoaming by hitting the foam contained therein. In Patent Document 2, a porous member having water repellency on the surface is disposed on the liquid surface in the container, bubbles on the liquid surface are attached to the porous member, and air is blown out from the micropores of the porous member. A device for defoaming by air pressure or the like is described. Patent Documents 3 and 4 describe devices that eliminate bubbles contained in a liquid by passing the liquid through a minute gap. Patent Document 5 describes an apparatus that eliminates bubbles contained in a liquid by passing the liquid through a magnetic field.

JP 2006-110543 A JP 2001-252504 A JP 2012-196595 A JP 2013-163157 A JP 2003-53373 A

  In the apparatus described in Patent Document 1, in order to give a blow of the rotating blades to the bubbles contained in the liquid, the rotating blades must be rotated at a high speed, which requires a high-speed rotating device. It tends to be higher. In the apparatus described in Patent Document 2, only the defoaming of the bubbles on the liquid surface attached to the porous member is possible, and a considerable number of bubbles contained in the liquid remain. In the devices described in Patent Documents 3 and 4, bubbles having a size equal to or smaller than the minute gap pass through the minute gap, so that the bubbles cannot be removed. The device described in Patent Document 5 requires a separate magnetic field generator, and tends to increase equipment costs, energy costs, and the like.

  This invention is made | formed in view of such a situation, and it aims at providing the defoaming apparatus which can defoam the foam contained in the liquid with a simple structure.

(Claim 1) The defoaming apparatus according to the present invention is arranged in a direction from the liquid surface side of the liquid stored in the container toward the bottom surface side of the container, A hollow cylindrical shaft member that can rotate relative to the shaft, a communication path that is formed in the shaft member and connects the hollow interior and the exterior of the shaft member, and an air supply that can supply air to the hollow interior of the shaft member An apparatus, and by rotating the container and the shaft member relative to each other to swivel the liquid containing the first foam accommodated in the container, the air supply device into the hollow interior of the shaft member Air is supplied to generate second bubbles from the communication path.
In this defoaming device, the first bubble is defoamed by breaking the second bubble, and therefore, the second bubble can be generated. Therefore, since the defoaming device can have a simple configuration, the device cost and energy cost can be reduced.

(Claim 2) The defoaming device is configured to collect the first bubbles contained in the liquid around the shaft member by relatively rotating the container and the shaft member; A defoaming step of causing the second bubbles generated from the communication path to collide with the first bubbles collected in the step to defoam the first bubbles together with the second bubbles.
As a result, the majority of the first bubbles are efficiently collected around the shaft member, and the second bubbles move along the shaft member, so that the second bubbles are surely secured to the collected first bubbles. Can collide with.
(Claim 3) The size of the second bubble may be larger than the size of the first bubble.
Thereby, since a big energy is given to the liquid level fluctuation | variation at the time of a 2nd bubble breaking, a 1st bubble is reliably defoamed.
(Claim 4) The shaft member may be provided so as to reach the liquid surface from the liquid in the container.
Thereby, since a 2nd bubble raises along the outer periphery of a shaft member, the 1st bubble gathered around the shaft member can be defoamed reliably.

(5) The communication path may be provided on the bottom surface side from the center of the bottom surface of the container and the liquid surface of the liquid in the container.
Thereby, since the 2nd bubble generate | occur | produces from the deep position in a liquid, it can float at high speed and can defoam the 1st bubble in a short time. Moreover, the 2nd bubble can unite with the 1st bubble which exists in the liquid, and can break up the said 1st bubble by breaking at the liquid level.

(Claim 6) The communication path may be formed in an opening that expands from the hollow interior of the shaft member toward the outer periphery.
Thereby, the second bubble can be generated with a large diameter.
(Claim 7) The defoaming device may include an agitating blade provided on the shaft member for rotating the liquid accommodated in the container.
Thereby, the shaft member can easily turn the liquid in the container by the rotation of the stirring blade.

(Claim 8) A plurality of the shaft members may be arranged in the container.
In the defoaming apparatus having such a configuration, the first foam can be simultaneously defoamed with the second foam in each shaft member in a large-capacity container, so that a large amount of liquid can be defoamed in a short time. It becomes.
(Claim 9) The shaft member may be configured to rotate with respect to the container and to be movable in the container.
In the defoaming apparatus having such a configuration, the first foam can be defoamed with the second foam by sequentially moving from one place to the other in a large-capacity container. Bubble processing becomes possible.

(Claim 10) The container may be provided with a decompression device for decompressing the inside of the container.
Thereby, since the inside of the container is depressurized by the decompression device, the defoaming of the first bubble having a smaller size than that at the atmospheric pressure can be performed.
(Claim 11) The air supply device may be provided with a valve capable of supplying and stopping the supply of air.
As a result, air is supplied only when necessary, and the operating cost can be reduced.
(Claim 12) The defoaming device is configured to rotate the liquid contained in the container by rotating the container and the shaft member relative to each other, and air from the air supply device to the hollow inside of the shaft member. To generate the second bubbles from the communication path.
During this turning, the first bubbles can be collected around the shaft member, so that the first bubbles can be substantially eliminated.

Embodiment of this invention: It is the schematic block diagram which looked at the defoaming apparatus from the side, and is the figure which made the container only the cross section in the height direction. Embodiment of this invention: It is the schematic block diagram which looked at the defoaming apparatus from the bottom face side. It is a flowchart for demonstrating the defoaming operation | movement by a defoaming apparatus. It is a figure which shows the preparation state by which the liquid is previously accommodated in the container. It is a figure which shows the state which the shaft member rotates and is collecting the 1st bubble. It is a figure which shows the state just before a 2nd bubble reaches | attains a liquid level. It is a figure which shows the state which the 1st bubble defoamed by the bubble breakage of the 2nd bubble. It is the schematic block diagram which looked at the 1st another example of the defoaming apparatus from the side, and is the figure which made the container only the cross section in the height direction. It is the schematic block diagram which looked at the 2nd another example of the defoaming apparatus from the side, and is the figure which made the container only the cross section in the height direction. It is the schematic block diagram which looked at the 3rd other example of the defoaming apparatus from the side, and is the figure which made the container only the cross section in the height direction.

(Configuration of defoaming device)
The defoaming apparatus of this embodiment is demonstrated with reference to FIG. The defoaming apparatus 1 is an apparatus for defoaming a liquid (for example, foam (corresponding to the “first foam” of the present invention) contained in a slurry of an active material for producing an electrode of a lithium ion secondary battery). And includes a container 2, a shaft member 3, a stirring blade 4, a rotating device 5, an air supply device 6, a decompression device 7, a driving device 8, and the like.

The container 2 is formed in a bottomed cylindrical shape that can accommodate a liquid therein. The upper surface of the opening of the container 2 is covered with a lid 21 that can be opened and closed.
The shaft member 3 is formed in a hollow cylindrical shape with one end closed, and is arranged in a direction from the liquid surface side of the liquid stored in the container 2 toward the bottom surface side of the container 2. The shaft member 3 is rotatably inserted in the center of the lid 21 through a mechanical seal (not shown) with the closed end 34 side facing down. The shaft member 3 is provided so as to reach the liquid surface from the liquid in the container 2 when the upper opening of the container 2 is covered with the lid 21 (see FIG. 3). On the closed end 34 side of the shaft member 3, a hollow interior 31 and an outer periphery 32 of the shaft member 3 are generated in order to generate bubbles (corresponding to “second bubbles” of the present invention) for eliminating the first bubbles. A communication path 33 is provided to connect the two.

The communication path 33 is provided on the bottom surface side from the center between the bottom surface of the container 2 and the liquid level of the liquid in the container 2. And the communication path 33 is formed in the opening which spreads toward the outer periphery 32 from the hollow inside 31 of the shaft member 3, in order to form so that the magnitude | size of a 2nd bubble may become larger than the magnitude | size of a 1st bubble. .
In the stirring blade 4, the rotation center of the stirring blade 4 is fixed to the closed end portion 34 of the shaft member 3. And the stirring blade 4 is formed in the U shape along the inner periphery of the container 2 so that the liquid in the container 2 can rotate easily within the container 2 (refer FIG. 4).

  The rotating device 5 includes a motor 51 and a gear mechanism 52. The motor 51 is fixed on the upper surface of the lid 21 in the vicinity of the shaft member 3 with the motor shaft 53 facing upward. The gear mechanism 52 includes a gear 54 fitted into the motor shaft 53, and a gear 55 meshed with the gear 54 and fitted on the upper end side of the shaft member 3. The rotational driving force of the motor 51 is transmitted to the shaft member 3 through gears 54 and 55.

  The air supply device 6 is a device that supplies compressed air to the hollow interior 31 of the shaft member 3, and includes a compressor 61, a valve 62, a rotary joint 63, and pipes 64 and 65. The compressor 61 is connected to the valve 62 by a pipe 64. The compressor 61 is used to form a large-diameter second bubble with high-pressure air. The valve 62 is connected to the rotary joint 63 and a pipe 65, and is configured to be openable and closable so that compressed air can be supplied only when necessary. The rotary joint 63 is connected to the upper end of the rotatable shaft member 3.

The decompression device 7 is a device that decompresses the inside of the container 2 and includes a vacuum pump 71 and a pipe 72. The vacuum pump 71 is connected to a hole provided in the lid 21 of the container 2 by a pipe 72.
The driving device 8 drives the motor 51 of the rotating device 5, drives the compressor 61 of the air supply device 6, opens and closes the valve 62, and drives the vacuum pump 71 of the decompression device 7.

(Defoaming action)
Next, the defoaming operation by the defoaming apparatus 1 will be described with reference to FIGS.
As shown in FIG. 3, it is assumed that the liquid L is stored in the container 2 in advance, the container 2 is sealed with the lid 21, and the valve 62 of the air supply device 6 is closed. In this state, the liquid L contains a large number of first bubbles B1.

  The driving device 8 starts driving the motor 51 of the rotating device 5 (step S1 in FIG. 2), and rotates the stirring blade 4 together with the shaft member 3. Thereby, as shown in FIG. 4, the liquid L accommodated in the container 2 rotates around the shaft member 3 and descends from the center of the container 2 to the bottom surface side of the container 2 as indicated by an arrow. Rotate to move up the inner peripheral side of the container 2 and return to the center of the container 2. Then, the liquid surface Ls of the liquid L in the container 2 is in a state where the center is depressed along the outer periphery 32 of the shaft member 3 due to centrifugal force and the outer side is lifted along the inner periphery of the container 2. Then, a large number of first bubbles B1 contained in the liquid L in the container 2 gather around the contact point between the liquid level Ls of the liquid L and the outer periphery 32 of the shaft member 3. (Equivalent to the “foam collecting step” of the present invention)

  Since the assembly of the first bubbles B1 can be completed by driving the motor 51 for a predetermined time obtained in advance through experiments or the like, the driving device 8 drives the motor 51 for a predetermined time (see FIG. 2). (Yes in step S2), the valve 62 is opened (step S3 in FIG. 2), and the compressor 61 of the air supply device 6 and the vacuum pump 71 of the decompression device 7 are started to be driven (step S4 in FIG. 2).

  Thereby, the compressed air generated in the compressor 61 is supplied to the hollow interior 31 of the shaft member 3 through the valve 62. As shown in FIG. 5, the compressed air supplied to the hollow interior 31 of the shaft member 3 is exhausted from the communication path 33 and formed as a second bubble B2. And the 2nd bubble B2 formed in the communicating path 33 rises along the outer periphery 32 of the shaft member 3, reaches the contact location of the liquid level Ls of the liquid L and the outer periphery 32 of the shaft member 3, and the said contact It collides with a plurality of first bubbles B1 gathered at the location. (Corresponds to the “defoaming step” of the present invention)

  In general, the larger the size of the bubbles, the easier it is to break the bubbles. Therefore, as shown in FIG. 6, the second bubbles B2 having a size larger than the first bubbles B1 are aligned with the liquid surface Ls of the liquid L and the axis. When the contact point with the outer periphery 32 of the member 3 is reached, bubbles are broken, and the first bubbles B1 are defoamed along with the bubbles of the second bubbles B2. At this time, since the second bubble B2 is generated from a deep position in the liquid L, it can float at a high speed, and the first bubble B1 can be removed in a short time. The following can be considered as a process of defoaming the first bubble B1. The first bubble B1 is defoamed by energy given by the liquid level fluctuation when the second bubble B2 breaks. Or the 1st bubble B1 unites with the 2nd bubble B2, and defoams with the bubble breakage of the 2nd bubble B2. Alternatively, the first bubble B1 is defoamed by the liquid splashed when the second bubble B2 breaks.

  At this time, since the inside of the container 2 is depressurized by the vacuum pump 71, the first bubble B1 having a smaller size than that at the atmospheric pressure can be defoamed. Since the defoaming of the first bubble B1 can be completed by driving the compressor 61 and the vacuum pump 71 for a predetermined time obtained in advance through experiments or the like, the driving device 8 drives the compressor 61 and the vacuum pump 71. Is performed for a predetermined time (Yes in step S5 in FIG. 2), the valve 62 is closed (step S6 in FIG. 2), and the driving of the motor 51, the compressor 61 and the vacuum pump 71 is stopped (step S7 in FIG. 2). Terminate the process.

  In the defoaming apparatus 1 having the above-described configuration, the first bubble B1 is defoamed by breaking the second bubble B2, so that the second bubble B2 may be generated. Therefore, since the defoaming apparatus 1 can be made into a simple structure, it can be set as the apparatus which restrained equipment cost, energy cost, etc. low. Further, when the liquid L is, for example, a slurry of an active material for manufacturing an electrode of a lithium ion secondary battery, the first bubble B1 contained in the slurry is coated with a thickener containing a surfactant, for example. Although it is difficult to defoam because it is stable, the defoaming apparatus 1 can easily defoam the first foam B1. Therefore, in the electrode manufacturing, it is possible to suppress the occurrence of poor application of the slurry of the active material material due to the first bubbles B1, thereby improving the electrode manufacturing yield. Further, the defoaming device 1 is configured to generate the second bubble B2 from the communication path 33 while turning the liquid L in the container 2, and during the turning of the liquid L, the first bubble B1 is pivoted. Since it can be collected around the member 2, the first bubble B1 can be substantially eliminated.

(Configuration of the first alternative form of the defoaming device)
A first alternative embodiment of the defoaming device will be described with reference to FIG. 7 shown corresponding to FIG. In addition, in the defoaming apparatus 10 of FIG. 7, the same number is attached | subjected about the structure same as the structure of the defoaming apparatus 1 shown in FIG. 1, and detailed description is abbreviate | omitted. The defoaming device 10 includes a plurality of sets (three sets in this example) of the shaft member 3, the stirring blade 4, the rotating device 5, and the rotary joint 63 of the air supply device 6. The three sets of shaft members 3 and the like are arranged in the container 2 with a predetermined interval. The rotary joints 63 are connected in parallel by a pipe 65. In the defoaming apparatus 1 having such a configuration, the first foam B1 can be broken simultaneously with the second foam B2 in each shaft member 3 in the large-capacity container 2, so that a large amount of the liquid L is defoamed. Processing is possible in a short time.

(Configuration of second alternative form of defoaming device)
A second embodiment of the defoaming device will be described with reference to FIG. 8 shown corresponding to FIG. In addition, in the defoaming apparatus 11 of FIG. 8, about the structure same as the structure of the defoaming apparatus 1 shown in FIG. 1, the same number is attached | subjected and detailed description is abbreviate | omitted. The defoaming device 11 is configured such that the rotating device 5 and the air supply device 6 are housed in a case 12 and the case 12 is movably attached to a moving rail 13 disposed above the container 2. In the defoaming apparatus 11 having such a configuration, since the first bubble B1 can be broken by the second bubble B2 by moving from one place to another place in the large-capacity container 2, a large amount of The defoaming treatment of the liquid L becomes possible. In addition, in this defoaming apparatus 11, since the rotation apparatus 5 etc. move, the lid | cover 21 and the decompression device 7 of the container 2 are not provided.

(Configuration of third alternative form of defoaming device)
A third embodiment of the defoaming device will be described with reference to FIG. 9 shown corresponding to FIG. In addition, in the defoaming apparatus 14 of FIG. 9, the same number is attached | subjected about the structure same as the structure of the defoaming apparatus 1 shown in FIG. 1, and detailed description is abbreviate | omitted. The defoaming device 14 does not include the shaft member 3 extending from the top surface to the bottom surface of the container 2, and has a hollow cylindrical shaft member 15 projecting from the bottom surface of the container 2 to the inside, and an upper portion of the shaft member 15 at the center. And a stirring blade 16 which is penetrated and fixed. In the upper part of the shaft member 15, a communication path 17 that communicates with the hollow interior of the shaft member 15 and generates the second bubble B2 for defoaming the first bubble B1 gradually spreads from below to above. Is provided. The defoaming device 14 includes the rotating device 5, the air supply device 6, and the driving device 8 on the lower end side of the shaft member 15. In the defoaming device 14 having such a configuration, since the rotating device 5 or the like is not provided on the lid 21 of the container 2, the opening / closing mechanism of the lid 21 is simplified.

  In the above-described embodiment, the communication path 33 is formed in an opening that widens from the hollow interior 31 of the shaft member 3 toward the outer periphery 32, but has the same cross-sectional shape from the hollow interior 31 of the shaft member 3 toward the outer periphery 32. You may form in the opening connected by. Moreover, although the defoaming apparatus 1, 10, 11, 14 provided with the shaft member 3 to which the stirring blades 4, 32 are fixed has been described, the defoaming device provided with only the shaft members 3, 31 without the stirring blades 4, 32. The same effect can be obtained even with an apparatus. Moreover, although the above-mentioned embodiment demonstrated the defoaming apparatuses 1, 10, 11, and 14 provided with the stirring blades 4 and 32 formed in the U shape along the inner periphery of the container 2, in the U shape For example, the same effect can be obtained even with a defoaming device including a stirring blade formed in a shape extending in the horizontal direction. In the above-described embodiment, the defoaming devices 1, 10, 11, and 14 are configured to rotate the stirring blades 4 and 32 with respect to the container 2. However, the configuration in which the container 2 is rotated with respect to the stirring blades 4 and 32 is described. The same effect can be obtained even with the defoaming apparatus.

  Further, in the above-described embodiment, the second bubble B2 is generated from the communication passage 33 while the liquid L in the container 2 is swirled. However, after the swirling of the liquid L in the container 2 is stopped, Even if the second bubbles B2 are generated from the passage 33, the first bubbles B1 can be collected around the shaft member 2 within a predetermined time, so that the first bubbles B1 can be substantially eliminated. Moreover, although the above-mentioned embodiment demonstrated the case where it applied to the slurry of the active material material for electrode manufacture of a lithium ion secondary battery, if it is a liquid containing a 1st bubble, it is applicable similarly.

1, 10, 11, 14: Defoaming device, 2: Container, 3, 31: Shaft member, 4, 32: Stirrer blade, 5: Rotating device, 6: Air supply device, 7: Pressure reducing device, 8: Drive device , 21: lid, 33: communication passage, 62: valve, B1: first bubble, B2: second bubble

Claims (12)

A container capable of containing a liquid;
A hollow cylindrical shaft member that is disposed in a direction from the liquid surface side of the liquid contained in the container toward the bottom surface side of the container and is rotatable relative to the container;
A communication path formed in the shaft member and connecting the hollow interior and exterior of the shaft member;
An air supply device capable of supplying air into the hollow interior of the shaft member;
With
The container and the shaft member are relatively rotated to swivel the liquid containing the first bubbles accommodated in the container, and air is supplied from the air supply device to the hollow interior of the shaft member to A defoaming device that generates second bubbles from the communication path. The defoaming device is
A foam collecting step for collecting the first bubbles contained in the liquid around the shaft member by relatively rotating the container and the shaft member;
A defoaming step of defoaming the first foam together with the second foam by colliding the second foam generated from the communication path with the first foam collected in the foam collection step;
An antifoaming device according to claim 1.   The size of said 2nd bubble is a defoaming apparatus of Claim 1 or 2 larger than the size of said 1st bubble.   The defoaming device according to any one of claims 1 to 3, wherein the shaft member is provided so as to reach the liquid surface from the liquid in the container.   The defoaming device according to any one of claims 1 to 4, wherein the communication path is provided on the bottom surface side from a center between a bottom surface of the container and a liquid surface of the liquid in the container.   The defoaming device according to claim 5, wherein the communication path is formed in an opening that extends from a hollow interior of the shaft member toward an outer periphery.   The defoaming apparatus according to any one of claims 1 to 6, further comprising a stirring blade that is provided on the shaft member and rotates the liquid contained in the container.   The defoaming device according to any one of claims 1 to 7, wherein a plurality of the shaft members are arranged in the container.   The defoaming device according to any one of claims 1 to 8, wherein the shaft member is configured to rotate with respect to the container and to be movable in the container.   The defoaming apparatus according to any one of claims 1 to 9, wherein the container is provided with a decompression device that decompresses the interior of the container.   The defoaming device according to any one of claims 1 to 10, wherein the air supply device is provided with a valve capable of supplying and stopping supply of the air.   The defoaming device supplies air from the air supply device to the hollow interior of the shaft member while rotating the liquid contained in the container by relatively rotating the container and the shaft member. The defoaming device according to any one of claims 1 to 11, wherein the second bubble is generated from the communication path.

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