JPS618145A - Method of pulverizing material to be pulverized - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for pulverizing pulverized material, and in particular provides a method for pulverizing pulverized material suitable for efficiently producing a pulverized product with a sharp particle size distribution and less coarse powder. It is.

Generally, when crushing crushed materials (raw materials), a crusher is selected taking into consideration the type and shape of the crushed materials, the desired crushing capacity, etc. It is extremely important to sharpen the particle size distribution and to improve the sharpness of coarse powder in order to effectively use crushed products, especially ultra-finely crushed products.

Conventionally, a jet pulverizer has been used as a pulverizer for obtaining ultrafinely pulverized products having a particle size of about 1 to 10 μm. This crusher utilizes fluid energy, and has a structure in which the fluid and the crushed material accompanying it are jetted and crushed by colliding with each other in the crusher, and in order to obtain crushed products with small particle size. Preferably used.

The particle size of finely crushed products produced by a crusher such as a mill can be controlled by controlling the type and amount of fluid supplied or the amount of crushed material supplied, but it is difficult to control such conditions. By simply carrying out this process, it was difficult to obtain a crushed product with a sharp particle size distribution and excellent ability to cut coarse powder.

As a result of intensive study on the above-mentioned problems, the present inventors found that
In order to increase the crushing efficiency using a jet crusher like the one mentioned above, we learned that it is necessary to suppress the agglomeration of the crushed material to the maximum in the classification zone inside the machine, and to do this, it is necessary to When obtaining a crushed product of The present inventors discovered that by pulverizing with a pulverizer to obtain the desired particle size, the particle size distribution of the crushed product becomes sharp and the coarse powder can be easily cut, and the present invention was proposed.

That is, in the present invention, when finely pulverizing crushed material using a jet pulverizer, the particle size of the crushed product is controlled by two or more crushing steps.
This is a method for pulverizing crushed material, which is characterized by pulverizing the material.

The most important feature of the present invention is that the particle size of the crushed product is controlled by two or more crushing processes in a jet crusher. In the past, crushing was carried out multiple times to control only the particle size of the crushed material, but in this case, it is possible to improve the crushing efficiency by selecting a highly efficient crusher according to the particle size of the crushed material. The purpose was to improve.

Therefore, in these types of pulverization, the size of the pulverizer generally increases depending on the pulverized material, and although the particle size becomes smaller as the number of times of pulverization increases, the particle size distribution at each particle size hardly changes.

On the other hand, as described above, in the present invention, by dividing the crushed material into two or more crushings using the same crusher of a jet crusher, the particle size distribution for each particle size is different, and the resultant material is obtained by the second or more crushing. The particle size distribution of the crushed product is extremely sharp and the coarse powder can be easily cut.

The jet pulverizer used in the present invention is a pulverizer that uses fluid energy, and has a structure in which the fluid and the pulverized material accompanying it are jetted and collided with each other in the pulverizer, thereby pulverizing the material. Examples include Jet-o-MiI5er, Miaronizer, and supersonic jet mill. Further, as the fluid used in the cough crusher, compressed air, heated compressed air, superheated steam, inert gas, etc. are used. The particle size of the crushed product pulverized by the jet pulverizer is approximately several μm.

The crushing materials used in the present invention include abrasive materials such as 810□, alumina, and silica sand; metal materials such as lead oxide, magnesite, and zinc oxide; and epoxy resins.

Commonly used resins such as acrylic resin, vinyl chloride, i-tyrene resin, and Teflon can be used without particular limitation.

A typical procedure of the crushing method according to the present invention will be described below. The initial pulverization is performed to obtain a particle size slightly larger than the desired particle size. As described above, the particle size can be controlled by changing the type of fluid, the amount supplied, or the amount of circulating material. The particle size at this time is 80% of the desired (target) grain size.
It is preferable to grind to a ratio of ~97%; if this ratio is too low, it is not practical because the number of times of grinding required to sharpen the particle size distribution increases. Furthermore, if the above ratio is too high, fluid energy will be lost, which is not preferable. The crushed product obtained by the above-mentioned crushing is then fed again to the crusher. In this case, the number of times of crushing can be determined by the type of crushing and the particle size distribution of the crushed product, but two times is sufficient, and it is not practical to do it three times or more because the effect will hardly change. .

Example 1 8102 granules having an average particle size of 20 μm were ground using a Jet Ohmizer pulverizer to a particle size of λ65 μm. The first pulverization was performed using TOXO 5102 with a supply amount of 1 klJ/Hr H superheated steam (230°C). The average particle diameter of the obtained crushed product was &3 μm, and the coarse powder cut (Dp 1 o/]) 1) 50) shown below was 1.7.

This crushed product was heated with superheated steam (230°C) lox.

When crushed again using a crusher, the average particle size was 2.65μ.
Cutting of coarse powder (])1)lj)/Dp50) is 1.4
It was 5.

Comparative Example 1 The same method as in Example 1 was carried out except that the average particle size was 2.65 μm by one pulverization using 14 kg of superheated steam. Cutting of coarse powder at this time (DplO/Dp50
) was 1.60.

Note: DI)10/DI)50 (90% particle size 150
% particle size) The closer this value is to 10, the sharper the particle size distribution becomes.

Claims (1)

[Scope of Claims] 1) A method of pulverizing pulverized material, characterized in that when pulverizing the granulated material using a jet pulverizer that utilizes fluid energy, the pulverized material is divided into two or more times. 2) The desired particle size of the crushed material obtained by the first crushing is 80 to 9
The method of finely pulverizing crushed material according to claim 1, characterized in that the crushed material is re-pulverized after being reduced to 7%.