JP2011005355A - Method for removing deposit on surface of medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of removing deposit on a surface of a medium without damaging the medium.SOLUTION: The medium, after used for crushing and mixing of materials and with the crushed materials and the like deposited on the surface thereof, is charged into a polishing tank 1 of a flow barrel polishing apparatus together with: a material harder than the deposit on the surface and softer than the medium, or abrasive grains having the same material as the media; a compound that dissolves the deposit on the surface or lowers the adhesiveness thereof to the medium; and water. Polishing force is imparted to the media surface by the turning flow of the mass M, and the deposit on the surface is removed without damaging the medium.

Description

The present invention relates to a method for removing surface deposits adhering to the surface of a medium used for pulverizing and mixing materials with a ball mill or the like.

Conventionally, materials are pulverized and mixed by rotating the material and hard media in a mill, rotating a ball mill that pulverizes the material into powder, and a pulverizing mill containing the material and hard media. For example, a vibration mill that pulverizes the material into powder is used. As media, ceramic balls made of alumina, zirconia, etc., metal balls made of stainless steel, etc. are used. The material to be crushed is pulverized by receiving an impact force from the media in the mill, but a part of the pulverized material is firmly fixed to the surface of the media in the pulverization process.
Reuse of media with deposits on the surface in this way may cause impurities to be mixed into the pulverized powder, so the media can be replaced with new media each time it is crushed or the media can be removed to remove the deposits. It is necessary to do. As a method for removing such surface deposits, for example, in Patent Document 1, alumina powder and methanol are placed in a pot together with stainless steel balls used for mechanical alloying, and the inside of the pot is replaced with argon gas. A method of rotating the pot to remove the metal powder adhering to the surfaces of the stainless pot and the stainless balls is shown.

JP-A-5-4054

In the above-described technique, the metal oxide used for the production of ferrite or the like is a fine powder and has a large surface area, so that the surface energy increases and the adhesion to the media increases, so that it is difficult to remove. Further, among metal powders used for mechanical alloying and the like, metal powders that are easily plastically deformed are difficult to remove because of their increased adhesion to media. When a large external force is applied to remove these, the media is damaged, and there is a problem that reproduction is difficult.

Therefore, an object of the present invention is to realize a method for removing surface deposits on media that can remove the surface deposits without damaging the media.

In order to achieve the above object, the present invention provides a method for removing surface deposits on media used in a ball mill or the like, wherein the surface deposits are dissolved or the surface deposits are removed. A compound that chemically reduces the adhesive force to the medium, a material harder than the surface deposit, a softer material than the medium, or abrasive grains made of the same material as the medium, the medium, water, Is put into a polishing tank of a barrel polishing apparatus, and a technical means is used to remove the surface deposits of the media by swirling and flowing.

According to the invention described in claim 1, in order to dissolve the surface deposits by the chemical action of the compound or to reduce the adhesion force to the media and to remove the surface deposits by the physical action of the abrasive grains, Surface deposits can be easily removed without applying a strong polishing force to the media.
In addition, since the abrasive grains are harder than the surface deposit and softer than the media, or the same material as the media, the surface deposit can be efficiently removed without damaging the media.

According to a second aspect of the present invention, there is used the technical means that the compound is an acidic compound in the method for removing surface deposits on the medium according to the first aspect.

When an acidic compound is used as in the invention described in claim 2, surface deposits made of metal oxide powder, mechanochemical metal powder, etc. can be efficiently removed. is there.
Here, the “acidic compound” is a concept including not only an acid compound among compounds used as a normal polishing aid but also an acidic chemical such as hydrochloric acid.

It is explanatory drawing which shows the structure of the fluid barrel grinding | polishing apparatus used for this invention.

The method for removing deposits on the surface of the media of the present invention will be described with reference to the drawings. For example, as shown in FIG. 1, the fluid barrel polishing apparatus used in the present invention has a fixed tank 2 in which a polishing tank 1 for polishing a workpiece is formed in a cylindrical shape, and a lower end opening inner peripheral portion of the fixed tank 2. And a platen-like turntable 4 that forms a sliding contact gap 3 and rotates horizontally. A passage 6 is formed between the turntable 4 and the bottom plate 5 of the fixed tank 2 so that a sliding contact gap 3 communicates with a hole 8 formed in the center of rotation of the turntable 4. The attached drain pipe 7 is connected.

Removal of media surface deposits is performed as follows. First, media used for pulverization and mixing of materials, with the crushed material and the like attached to the surface, abrasive grains as an abrasive, a compound as a polishing aid, and water, a polishing tank 1 of a fluid barrel polishing apparatus 1 In When the turntable 4 is rotated, a mass M is formed. The mass M ascends along the inner wall of the polishing tank 1 as indicated by an arrow in the figure due to centrifugal force. Then, the rising mass M swirls and flows, so that a polishing force is applied to the media surface, and surface deposits are removed.

The compound uses a compound that dissolves the surface deposit or chemically reduces the adhesion of the surface deposit to the medium. For example, when the medium is an alumina sphere and the surface deposit is a metal powder, an acidic compound can be suitably used. Thereby, metal powder can be melt | dissolved or the adhesive force with respect to the medium of metal powder can be reduced. It is desirable for the compound not to be damaged by reaction with the media.

The abrasive grains are harder than the surface deposit and softer than the media, or abrasive grains made of the same material as the media. For example, when the medium is an alumina sphere, alumina powder is used as the abrasive grains, or a softer material than alumina such as silica powder and cerium oxide powder is used. As the abrasive grains, it is preferable to use a grain size that does not damage the media, for example, a grain size of about several μm to 200 μm. Thereby, surface deposits can be efficiently removed without damaging the media.

As described above, the surface chemicals are dissolved by the chemical action of the compound, or the adhesion force to the media is reduced, and the physical adhesion of the abrasive grains removes the surface deposits. Surface deposits can be easily removed without loading. As a result, the media can be reused.

When the fluid barrel apparatus shown in FIG. 1 is used, it is possible to perform a cleaning process on the media from which surface deposits have been removed. In order to perform the cleaning process, cleaning water is continuously supplied into the polishing tank 1 while the mass M is caused to flow by the rotating disk 4, and the mass M is cleaned. Since the surface deposits, abrasive grains, compound, and water in the mass M are discharged from the drainage pipe 7 to the outside of the fluid barrel polishing apparatus through the sliding contact gap 3, the hole 8 and the passage 6 together with the cleaning water. Only the applied media can remain in the polishing tank 1.

(Example of change)
As long as the compound can dissolve the surface deposits or chemically reduce the adhesion of the surface deposits to the media, the compound is not limited to acidic, and is mainly composed of an alkaline compound, an organic solvent, or a surfactant. A compound etc. can also be used.

(Example)
Examples of the present invention are shown below. In this embodiment, three types of alumina spheres of φ10, 20, and 30 mm were used as media. This media was used for pulverization and mixing with metal oxide, and iron oxide or the like was adhered to the surface.

As a fluid barrel polishing device, a fluid barrel polishing device (manufactured by Shinto Blator: EVF-04) shown in FIG. 1 was used.

As abrasive grains, alumina powder having an average particle diameter of 180 μm was used. As the compound, a liquid acidic compound (manufactured by Shinto Blator: CLL) having an organic acid as a main component and having a pH of 3.1 at a concentration of 1% was used. The media to be processed had a capacity of 5 L and a weight of 10 kg.

The polishing tank 1 was charged with 100 g of abrasive grains, 30 mL of compound, and 5 L of water, and the process of washing after polishing for 20 minutes was repeated three times. As a result, the surface adhered without damaging the media. The metal oxide could be removed.

In addition, this invention is not limited by said Example, According to the kind of media, a surface deposit | attachment, etc., the kind of compound, an abrasive grain, etc. can be selected suitably.

[Effect of the embodiment]
(1) According to the fluid barrel polishing method of the present invention, surface deposits are dissolved by the chemical action of the compound, or the adhesion to the media is reduced, and the surface deposits are removed by the physical action of the abrasive grains. Therefore, surface deposits can be easily removed without applying a strong polishing force to the media.
In addition, since the abrasive grains are harder than the surface deposit and softer than the media, or the same material as the media, the surface deposit can be efficiently removed without damaging the media.

(2) Use of an acidic compound is preferable because surface deposits made of metal oxide powder, mechanochemical metal powder, and the like can be efficiently removed.

[Other Embodiments]
In the embodiment described above, the fluid barrel polishing apparatus shown in FIG. 1 is adopted as the barrel polishing apparatus, but the present invention is not limited to this, and various barrel apparatuses can be used.

DESCRIPTION OF SYMBOLS 1 Polishing tank 2 Fixed tank 3 Sliding contact gap 4 Turntable 5 Bottom plate 6 Passage 7 Drain pipe 8 Hole M Mass

Claims (2)

A method for removing surface deposits on media used for grinding and mixing of materials with a ball mill, etc.
The media;
A compound that dissolves the surface deposit or chemically reduces the adhesion of the surface deposit to the media;
A material that is harder than the surface deposit and softer than the media, or an abrasive made of the same material as the media,
A method of removing deposits on the surface of media, wherein water is poured into a polishing tank of a barrel polishing apparatus and swirling to remove the deposits on the surface of the media. The method according to claim 1, wherein the compound is an acidic compound.

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