JPH04122432A - Granulating apparatus for powder - Google Patents

Abstract

PURPOSE:To improve disintegrating yield and a grinding/screening time by subjecting a powdery raw material to compression molding between a pair of press rolls wherein a roll having recessed grooves right-angled to the peripheral direction thereof continuously provided thereto is combined with a roll having recessed grooves parallel to the peripheral direction thereof continuously provided thereto. CONSTITUTION:Press rolls 4, 4' respectively having semicircular recessed parts 14 right-angled to the peripheral direction thereof and semicircular recessed parts 15 parallel to the peripheral direction thereof continuously formed to the surfaces thereof are arranged at the proper interval corresponding to a desired particle size. A raw material 2 is pressed by a pair of these press rolls 4, 4' to be molded into a plate- shaped article 5 having semicolumnar protruding parts crossing each other at a right angle continuously formed to both surfaces thereof. The plate-shaped article 5 is bent along the lateral grooves thereof by the curvatures of disintegrating rolls 7,7' and cut along the longitudinal grooves thereof at the same time by the acute angle teeth of said rolls 7, 7', and discharged through the recessed parts 19 of the disintegrating rolls 7, 7' to obtain particles 8 each having semicolumnar protruding parts crossing each other at a right angle formed to the surface and rear thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to granulation of powdered materials, particularly to a granulation device that does not use water or the like for granulation.

[Problems with the Prior Art] Generally, one of the purposes of granulating powdery materials is to facilitate handling, and various granulation methods and devices have been introduced or adopted heretofore.

Among them, compression granulation is known as a method that can granulate powdered materials in a dry state, and the representative methods are tabletting, briquerating, and compacting. Due to the mechanism of filling the powder and compressing it with a piston, the grain shape is uniform and the grains look beautiful, but on the other hand, it has the disadvantage that it is difficult to obtain small grains of 4 mm or less and is not suitable for mass production.

In addition, briquenting is a method of compression molding powder between two opposing rolls with many desired recesses cut into the surface to obtain granules, but when molding small particles, the molded product may be unstable due to cracking or peeling phenomenon. However, there are disadvantages in that it is difficult to obtain a product using adhesive materials, and it is difficult to prevent holes from clogging when molding adhesive substances.

Compacting, on the other hand, is a method in which powder is compression-molded between two cols facing each other, and the resulting flat plate is crushed into predetermined particle sizes using a crusher to produce products, and is suitable for mass production. However, the granules obtained are irregularly shaped, and compared to spherical products, the improvement in handling that can be obtained with each granulation is low, which is a drawback that users do not like.

[Problems to be Solved by the Invention] The present inventors have improved compacting rolls and crushers to enable mass production, which is an advantage of compacting, and to obtain particles with a constant and nearly spherical shape. The present invention was arrived at as a result of various studies on a granulation method that combines the advantages of briquenting.

[Means for Solving the Problems] In other words, in producing granular materials, the present invention uses a roll having a continuous concave groove perpendicular to the circumferential direction and a continuous concave groove parallel to the circumferential direction to produce a granular material. A plate-shaped article having convex portions perpendicular to each other on both the front and back surfaces obtained by compression molding is charged between a pair of press rolls that are combined with a roll having a By passing between a pair of rolls each having a diameter of 1:40 or less and acute-angled teeth along the circumferential direction at the same interval and 4 times the interval, the plate-shaped object is cut along the recessed part, and the upper and lower halves are separated. It has a cylindrical convex part and the compressed surface thickness: Length in the cutting direction: Approximately 1:1:1 in the cutting direction
This provides a granulation method for obtaining granular materials.

Next, an example of a manufacturing apparatus according to the present invention will be explained with reference to the drawings. FIG. 1 shows the overall configuration of a manufacturing apparatus 1. As shown in FIG.

The manufacturing device 1 includes a raw material feeder 3 that supplies powdered raw material 2;
A press roll 4.4" for pressing the raw material 2 and a crushing roll 7.7" for separating the plate-like material 5 formed by the press roll 4.4" and having semi-cylindrical protrusions orthogonal to each other on both the front and back sides. and the crushed grains 8 formed by the crushing roll 7.7゛
A sieving machine 10 that classifies the shavings 12 and spherical particles 11 generated during polishing by the sifting machine 9, and transporting the shavings 12 back to the raw material feeder 3. It is equipped with 13 machines.

Press roll 4.4 as shown in detail in FIG.
For example, desired semicircular recesses 14 perpendicular to the circumferential direction of the roll and semicircular recesses 15 parallel to the circumferential direction of the roll are each continuously formed on the surface, and both rolls also have desired grains. They are arranged at appropriate intervals corresponding to the diameter.Furthermore, it is preferable that the shape of each recess 14, 15 is the same if the purpose is to obtain spherical particles in the end.

The raw material 2 is processed by this pair of press rolls at 4.4 degrees.
A pressure of 1.5 t/cm or less is applied to form a plate-like object 5 having continuous semi-cylindrical convex portions orthogonal to each other on both surfaces. At this time, if the forming pressure is too high, the powdery raw material 2 will stick to the roll 4 having a semicircular concave portion perpendicular to the circumferential direction with strong compressive force, making it difficult to separate it from the roll 4 and forming the desired plate-like material 5. Molding becomes insufficient. On the other hand, general compacting is, for example, 2 to 4 t/in the case of advanced chemical fertilizers.
While the molding pressure of cm is required, this method requires a molding pressure of 1 cm.
It has the advantage of requiring only about half the pressure of ~1.5 t/cm.

The plate-like material 5 thus obtained is transferred to a crusher 7.7 with rolls 4"
It is guided by a guide plate 6 having the same concave portion. As shown in detail in Part 3, the crusher 7.7' has dimensions such that the diameter 17 is 1=40 or less with respect to the radius of curvature of the convex part 16 of the plate-like object 5, and it is installed along the circumferential direction. The intervals between the sharp teeth 18 are 1:1 and 1:4, and the radius of curvature of the recess 19 adjacent to the acute tooth is 1:1 to 1.5 and 1:1.5 to 2.0. A pair of rolls whose depth is in the range of 1.0 to 1.5 of the thickness of the plate-like material 5, and both rolls have acute-angled teeth 18.
are located on the central extension line of each recess 19, and are arranged so that the clearance 20 between the cors is approximately 1/3 of the thickness of the plate-like material 5.

The plate-like material 5 sent to such a crushing roll 7.7° is bent along the horizontal groove of the plate-like material 5 by the curvature of the crushing roll 7, ■'', and at the same time, the plate-like material 5 is sent to the crushing roll 7.7 Particles 8 are cut along the narrowing grooves of the plate-like material 5 by the acute-angled teeth 18 of the ", and passed through and discharged through the recesses 19 of the crushing roll 7.7", and have semi-cylindrical protrusions perpendicular to each other on the front and back sides. Become.

The particles 8 thus obtained are sent to a polishing and sizing R9 to round the corners and make them spherical. The granulator 9 obtains spherical particles by polishing using a known technique, for example, a Marmerizer manufactured by Fuji Baudal.

Note that the shavings 12 generated during this polishing are classified by the next sieve separator 10 and returned to the raw material feeder 3 by a transporter 13.

According to the apparatus according to the present invention described above, the yield can be improved compared to conventional compacting apparatuses, and the time for polishing and forming can also be shortened.

Examples manufactured using the apparatus according to the present invention will be shown below, but the invention is not limited thereto.

Example 1 Powdered raw materials consisting of 33 parts of ammonium chloride, 37 parts of ammonium phosphorus, 25 parts of chloride treatment, and 5 parts of gypsum were fed into a press roll.
It was molded at a pressure of cm to obtain a plate-like product having continuous semi-cylindrical convex portions orthogonal to each other on the front and back sides.

The press roll is perpendicular to the circumferential direction with R = 2.0 mm 1 depth -
A set of two rolls: a roll with a continuous semicircular groove of 1.0 mm, and a roll with a continuous semicircular groove of R-20 mm and depth -1.0 mm parallel to the circumferential direction. The plate-shaped material formed from the roll by the press roll and having semi-cylindrical convex portions orthogonal to each other continuously on the front and back sides was then guided by a guide and sent to a crushing roll (peripheral speed 0.2 m/sec).

The crushing rolls are made of metal and consist of a set of two rolls each having continuous acute-angled protrusions along the circumferential direction at pitches of 4.5 mm and 9 mm and depths of -2.5 mm and 3.5 mm. The rolls are arranged so that the acute angle teeth are located on the extension line of the center of the four parts of the rolls facing each other, and the clearance between the rolls is set at 0 mm.

The obtained crushed particles have an approximate thickness of −3.8 mm, and a medium thickness of 4.0 mm.
The crushed particles with a length of 0 mm and a length of -4 mm and above and below were introduced into a grinding machine to obtain spherical particles with a diameter of 2 to 4 mm. The results of the obtained spherical particles are shown in Table 1.

In addition, Table 1 also shows a comparison when the press roll of the same apparatus was replaced with a flat roll and compacting was performed in the same manner.

Table 1 [Effects of the Invention] As described above, according to the present invention, the compacting pressure is low, and both the crushing yield and the grinding and sizing time are significantly improved, and efficient granulation is possible.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an embodiment of a device according to the invention. FIG. 2 is a perspective view showing the main parts of the device shown in FIG. 1. FIG. 3 is a sectional view showing the arrangement of the crushing rolls. FIG. 4 is a photograph of a plate-shaped molded product produced by the apparatus according to the present invention. FIG. 5 is a photograph of semi-cylindrical particles obtained by crushing a plate-shaped molded product. FIG. 6 is a photograph showing the appearance of spherical particles after polishing and grading.

Claims (4)

[Claims] (1) A powder material is compression-molded using a pair of press rolls, which are a combination of a roll having continuous concave grooves perpendicular to the circumferential direction and a roll having continuous concave grooves parallel to the circumferential direction. A granulation device that separates a plate-like material having convex portions perpendicular to each other on both the front and back surfaces along the concave portions to produce granules. (2) The granulating apparatus according to claim 1, wherein the concave grooves of the two rolls intersect at right angles. (3) The granulation apparatus according to claim 1, wherein the compression-molded plate-like material having convex portions perpendicular to each other on both surfaces is cut off along the concave portions to obtain granules having semi-cylindrical convex portions on the upper and lower sides. (4) The granulation device according to claim 3, comprising a pair of rolls arranged such that the acute-angled teeth are located in an extension of the centers of the recesses of the rolls facing each other.