JPH0532096B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a continuous surface processing method for inorganic solid particles.

[Conventional technology]

Recently, ceramics, powder metallurgy technology, etc. have been attracting attention, and the application fields of powder are expanding. There is a growing need for particles with low That is,
The above-mentioned needs are increasing due to improved moldability in the molding process, increased density of molded products, improved powder handling, production of high-purity products, and increased hiding power in paint technology.

Conventionally, it has been known that as a surface treatment method for this type of inorganic solid particles, an impact type crusher such as that disclosed in JP-A-62-221434 can be used, for example.

[Problem to be solved by the invention]

However, the above-mentioned conventional method for surface processing of inorganic solid particles has the following technical problems.

(1) Inorganic solid particles with irregular particle shapes or whose surfaces are contaminated with oxides, etc. are spheroidized only by collision between the rotor blades and stator of the impact crusher, so the energy is not absorbed into the spherical shape. Because of this, it is not consumed effectively and the energy required is large.

(2) Since the above-mentioned inorganic solid particles are processed in a batch operation while being circulated in an impact-type pulverizer, product recovery is complicated and inefficient.

The present invention solves these conventional problems, and enables large-capacity surface processing to remove irregularities in inorganic solid particles to make them substantially spherical, or to remove contaminated areas due to oxides, etc. Another object of the present invention is to provide an excellent continuous surface processing method for inorganic solid particles that can be realized industrially under continuous operation.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a surface processing method for inorganic solid particles for continuously removing contaminated parts on the surface of inorganic solid particles for surface processing,
A cylindrical rotor and a small space on the outside of the rotor
a main body having a stator fitted therein, the outer surface of the rotor and the inner surface of the stator having a large number of continuous protrusions parallel to the generatrix in the circumferential direction; and one end of the main body. has a supply port through which irregularly shaped inorganic solid particles having contaminated portions flow in the tangential direction of the rotor together with an airflow made of an inert gas, and the other end has a surface-treated material and a supply port through which the airflow and a discharge port for discharging from the tangential direction of the rotor, and the distance between the tip of each protrusion and the tip thereof is 0.5 to 6.
mm, and by the rotation of the rotor, a large number of micro-eddy currents are created in the gap, a spirally flowing air current is formed at high speed, and the irregularly shaped inorganic solid particles dispersed in the air flow are forced to interact strongly with each other. The surface is processed by contact.

[Effect]

The present invention has the following effects due to the above configuration.

In other words, when the rotor rotates at a high speed and a large number of minute vortices exist between the rotor and the stator, a high-speed airflow that moves in a spiral is formed, and irregular particles with contaminants in the airflow are formed. When the inorganic solid particles are dispersed and communicated with each other, as the air flow flows, the inorganic solid particles come into strong contact with each other, and a peeling action is continuously performed, and the irregular portions of the inorganic solid particles are removed. After exfoliation, the surface can be processed into substantially spherical inorganic solid particles. Furthermore, when inorganic solid particles whose surfaces are contaminated with oxides, etc. are dispersed and communicated, the contaminated portions with oxides, etc. are similarly peeled off and removed by the above-mentioned air flow, and in effect, The surface of inorganic solid particles consisting of a clean part can be processed.

If the distance between the tip of the protruding material on the rotor and the tip of the protruding material on the stator is 0.5 mm or less, the contact with the main body of the processed material will increase significantly, causing adhesion and the above distance. Problems such as blockage occur. Also,
Similarly, if the diameter is 6 mm or more, a high-speed airflow that moves in a spiral cannot be formed if a large number of minute eddies are present. Therefore, the distance between the tip of the protrusion on the rotor and the tip of the protrusion on the stator is
The width is limited to 0.5 to 6 mm so that it can be operated stably and, if a large number of micro-eddy currents are present, a strong flow of high-speed airflow moving in a spiral shape can be generated.

Typical inorganic solid particles whose surface can be processed by the method of the present invention include Fe powder, Ni, Ni-Fe, metal powder such as stainless steel, CaCo ₃ , SiO ₂ , TiO ₂ ,
Examples include Al-Ti compounds, Fe ₂ O ₃ , and ceramics. However, it is not limited to these materials, and includes various materials used in industrial fields such as powder metallurgy, electricity, magnetic materials, electronic materials, cosmetics, paints, printing inks, coloring materials, rubber, and ceramics. Can be applied.

〔Example〕

FIG. 1 is a schematic cross-sectional view of an apparatus for carrying out a continuous surface processing method according to an embodiment of the present invention, FIG. 2 is a plan view showing the cross-sectional shapes of the rotor and stator in FIG. 1, and FIG. 1 is a flow diagram using the illustrated apparatus.

In FIG. 1, 10 indicates the main body of the device,
A cylindrical rotor 12 is provided in the center, and a cylindrical stator 18 is provided outside the rotor 12. Both the rotor 12 and the stator 18 are placed on the base 11 of the main body 10. The rotor 12 has a vertical rotation shaft 14, which is supported by a bearing 25 provided on the top plate 26 and a bearing 27 provided on the base 11, and a drive device (not shown) is provided at the lower end of the vertical rotation shaft 14. A V-pulley 28 driven by is attached.

A supply port 22 is attached to the lower end of the main body 10 through which irregularly shaped inorganic solid particles having a contaminated portion flow in in a tangential direction of the rotor 12 together with an air flow made of an inert gas. A discharge port 24 is attached to the upper end of the rotor 10 for discharging the surface-treated material and the air flow from the tangential direction of the rotor 12.

On the outer surface of the rotor 12, a large number of protrusions 16 parallel to the generatrix are arranged continuously in the circumferential direction, and on the inner surface of the stator 18, a large number of protrusions 20 parallel to the generatrix are arranged circumferentially. are placed consecutively.

That is, as shown in FIG. 2, a large number of protrusions 16 are continuously arranged on the rotor 12, and the protrusions 16 have a triangular tooth-shaped cross section, but other cross-sectional shapes are also possible. Many of them can also be adopted.
Further, a small distance 30, that is, 0.5 to 6 mm, is left between the tip 16a of the protrusion 16 of the rotor 12 and the tip 20a of the protrusion 20 of the stator 18. Next, due to the high speed rotation of the rotor 12, there is a first gap between the rotor 12 and the stator 18.
A high-speed airflow flows due to the airflow flowing in from the supply port 22 shown in the figure, and as shown in Fig. 2, the airflow flows in a spiral shape at high speed in the upper direction when a large number of minute eddies are present in the gap 30, as shown in Fig. 2. Airflow is discharged from the discharge port 24 of the main body 10 as shown in FIG. In the above, inorganic solid particles are dispersed in the airflow flowing in from the supply port 22, and in the process of passing through the above-mentioned gap 30 and being discharged from the discharge port 24,
Due to the strong contact of the inorganic solid particles with each other due to the intense flow of the high-speed airflow, a frictional action is performed, and the irregular portions are peeled off and removed, and substantially
It is possible to continuously process the surface of spherical inorganic solid particles. In addition, in the above process, when inorganic solid particles such as iron powder or copper powder whose surfaces are contaminated with metal oxides, etc. are communicated, the surface contaminated with the oxides, etc. is peeled off and removed, and in effect, The surface of inorganic solid particles consisting of a clean part can be processed.

Here, the operation of the apparatus will be explained with reference to FIG. First, the atmosphere in the system is replaced by inert gas supplied from the inert gas generator 40, and the oxygen concentration meter 4 provided at the outlet of the exhaust port 24
5 to monitor and adjust the oxygen concentration in the system atmosphere. The inorganic solid particles are supplied into the system by the supply device 42, dispersed in the airflow, and flowed into the supply port 22 of the main body 10. Rotor 12 and stator 18 of main body 10
As described above, a high-speed airflow flows between the two, and the airflow is discharged from the outlet 24. The product from which irregularities have been peeled off within the main body 10 is collected by a product collection means 34, separated and removed from the airflow, and is widely used as a spherical product 37. Product recovery means 3
Irregular portions made of fine powder that were not sufficiently collected in step 4 are collected with high efficiency by fine powder collection means 36 to obtain fine powder 39, which is separated out of the system.

The airflow from the fine powder collection section 36 is circulated within the system by the blower 38, and the circulating flow 43 is again
It flows into the supply port 22 mentioned above. The part indicated by the double chain line 32 shows the classifier, and if necessary,
It is provided subsequent to the discharge port 24 of the main body 10, and the pulverized product is classified into coarse powder and fine powder. The fine powder is then flowed into the product recovery means 34 for surface processing.

In the above embodiment, the rotor and stator are arranged in the vertical axis direction, but they can also be arranged in the horizontal axis direction. Furthermore, all or part of the protruding materials of the rotor and stator can be made of substantially the same material as the inorganic solid particles, and further can be made of a ceramic material such as ZrO ₂ or a cemented carbide. can.

〔Effect of the invention〕

According to the present invention, the inorganic solid particles are dispersed and communicated with the air current flowing at high speed in a spiral shape by creating a large number of minute vortices between the rotor and the stator due to the rotation of the rotor. Due to the strong contact between the particles, the irregularities of the inorganic solid particles can be removed and the surface processed into a substantially continuous spherical shape.
Furthermore, by dispersing inorganic solid particles whose surfaces are contaminated with oxides or the like into an air stream, the contaminants caused by the oxides or the like can be removed and the surface processed to be clean.

Furthermore, even when there are many types of inorganic solid particles to be treated, by optimizing the operating conditions of the equipment,
The surface of inorganic solid particles can be efficiently and industrially realized in a large-capacity, continuous operation.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of an apparatus for carrying out a continuous surface processing method for inorganic solid particles in an embodiment of the present invention, FIG. 2 is a plan view showing the cross-sectional shapes of the rotor and stator in FIG. 3 is a flowchart using the apparatus shown in FIG. 1, and FIGS. 4a and 4b are scanning electron micrographs before and after surface processing of inorganic solid particles by the apparatus shown in FIG. 1. 10... Main body, 12... Rotor, 18... Stator, 16, 20... Projection material, 22... Supply port, 2
4...Exhaust port, 30...time.

Claims (1)

[Claims] 1. A surface processing method for inorganic solid particles for continuously removing contaminated parts on the surface of the inorganic solid particles and processing the surface, which comprises a rotor having a cylindrical shape and a slight gap on the outside of the rotor. The main body has a stator fitted with a rotor, and a large number of protrusions parallel to the generatrix are continuously provided in the circumferential direction on the outer surface of the rotor and the inner surface of the stator. a supply port for flowing irregularly shaped inorganic solid particles having an inert gas in the tangential direction of the rotor together with an air flow consisting of an inert gas; and a discharge port for discharging from the tangential direction of the rotor, and the distance between the tip of each protrusion and the discharge port is provided.
is 0.5 to 6 mm, and a large number of micro-eddy currents are created in the space by the rotation of the rotor, and a spirally flowing air current is formed at high speed, and the irregularly shaped inorganic solid particles dispersed in the air current are mutually dispersed. A continuous surface processing method for inorganic solid particles, characterized in that the surface is processed by strong contact with the particles.