JPS5959240A - Wet extrusion granulator - Google Patents

Abstract

PURPOSE:To reduce cost to a large extent, in a granulator for extruding a wet powder material from the small orifices of a die by a rotor rotating and revolving on the die, by forming the die from a thin plate while a back-up plate is arranged to the under surface thereof. CONSTITUTION:A die 6 having a plurality of small orifices provided thereto by drilling is arranged to the inner bottom part of a granulation chamber 1 comprising an upright cylinder while a rotor 10 tumbling on the die 6 is provided in the chamber 1 and either one of the rotor 10 and the die 6 is rotated around the axial line of the chamber 1 and extrude a charged material from the small orifices 5 to perform granulation. In this wet extrusion granulator, the die 6 is formed of a thin plate having a plurality of the small orifices 5 provided thereto by drilling and a back-up plate 13 having a plurality orifices 12 communicated with a plurality of the small orifices 5 provided thereto by drilling is arranged to the under surface thereof. That is, by reducing the thickness of the die, the small orifices for granulation can be simply formed by press punching or the like and the amount of expensive special steel to be used is reduced largely as compared to a conventional one and, therefore, the cost is reduced to a large extent.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention is a wet extrusion granulator, in particular, the granulation chamber is an upright cylinder, and a die with many small holes for forming granules is disposed at the inner bottom of the granulation chamber. The present invention relates to a vertical wet extrusion granulator that extrudes a wet powder material charged into a mold through small holes of a die while kneading and kneading it with a rotor that rotates and revolves on a die.

Conventionally, various types of granulators of this type have been known, including a horizontal type with the axis of the granulation chamber horizontal and a vertical type with the axis line vertical. , one in which the granules are extruded in the radial direction by a rotor rotating inside the granulation chamber, and another in which a die is provided as a flat plate on the cylindrical end face of the granulation chamber, and the rotor rotates inside or on the top of the die for granulation. Various shapes are known, such as those that extrude the granules in the axial direction of the chamber.0 Those that have a cylindrical die and extrude the granules in the radial direction are: Although the thickness of the die is relatively thin, the material fed inside the die is pressurized and kneaded using a screw feed method, so the temperature of the wet material rises due to the pressure, and the temperature rise causes deterioration. It is not suitable for granulating materials that are wet and wet, and it is necessary to provide a cooling jacket in the supply section of the wet material to prevent the humidity from increasing, which makes the granulator structure complicated. There is.

In the case where the die is placed on the cylindrical end surface, the internal pressure of the material being kneaded and kneaded in the granulation chamber and the pressurizing force of the die,
The load on the die becomes extremely large, making it impossible to reduce the thickness of the die. Therefore, the length of the small hole in the die for forming granules becomes very long compared to its diameter, and the small hole becomes easily clogged during granulation. water) cannot be kept low.

On the other hand, a wet extrusion granulator is also known, in which a disc-shaped die is arranged at the inner bottom of an upright cylindrical granulation chamber, and a rotor is rotated and revolved on the disc-shaped die. Since the pressing force of the bittern rotor is very large, the thickness of the die becomes very thick compared to the diameter of the granules (the diameter of the small holes in the die).

The fact that the plate thickness is thick compared to the diameter of the small holes for granule molding means that the friction between the material being extruded and the die becomes very large, and for this reason, as mentioned above, the For example, in the case of materials that melt when heated, the extrusion speed or However, it is not possible to increase the pressing force and is inefficient, and the particle size of the granulated product is generally up to about 3X, and there are few examples of producing granules with a smaller diameter.

[-Therefore, in conventional wet extrusion granulators, it is necessary to increase the moisture content of the material to some extent. It is not possible to produce particles with a small diameter of 07 or less. There are drawbacks such as. In order to prevent deformation and abrasion of the small holes, dies like this are generally made of a special material that has been heat-treated to have daylight hardness, and its thickness means that the material cost is significant. This means that it will be very expensive. 1 Furthermore, the fact that the granulation material has a high moisture content means that the granules extruded from the die tend to stick together and form a lump. To prevent this, it is necessary to dry quickly. In addition, a large amount of heated air is required to evaporate this moisture, resulting in a large amount of energy consumption.

The purpose of this invention is to reduce the wetness of the material, that is, the water content, as much as possible in the above-mentioned wet extrusion granulation method, thereby enabling highly efficient granulation without deterioration of the material. do. The purpose is to still enable granulation with a diameter of, for example, 0.5% or less. Furthermore, the die thickness can be made as thin as possible to significantly reduce the cost.

To explain an embodiment, as shown in FIGS. 1 and 2, the top surface has an input port 2 into which a suitably moistened powder material is input, and the bottom part has an input port 2 for discharging the granulated material. An upright cylindrical granulation chamber 1 provided with an outlet 3 and installed on a frame 4
A drive shaft 7 having a drive section (not shown) located below the granulation chamber 1 is arranged to run vertically through the center of the granulation chamber 1. will be established.

A rotor 10 is attached to the tip of a support arm 9 supported on a support block 8 fixedly mounted on the shaft in a cross-shaped orthogonal arrangement to the shaft 7.
is rotatably supported via a bearing 11. Thus, with the drive shaft rotating 70 times, the rotor 0 is rotated and revolved on the die 6, and the material is extruded from the small hole 5 of the die 6 while being kneaded and kneaded by the rotor 10. In the wet extrusion granulator of the present invention, the die 6 is formed of a thin plate having a large number of small holes 5, and the diameter of the small hole 5 connected to the plurality of small holes 5 is larger than the diameter of the small hole 5 connected to the plurality of small holes 5 on the lower surface. A backup plate 13 having a large number of holes 12 of the same diameter is arranged and fixed together with the die 6 at the inner bottom of the granulation chamber l.

In the figure, a drive shaft 7 is supported by a frame 4 via bearings 14 and 15, and includes a die 6 and a backup plate 1.
A support block 8 is fastened and fixed to the upper end portion of the support block 3 inserted through the center thereof using a nut 16 or the like. A cover 17 is fixed to the drive shaft 7 by fitting onto the upper end of the drive shaft 7 to cover the nut 16 and the threaded portion with which it is fitted; An arm 18 is provided, and a scraper 19 provided along the cylindrical inner wall surface of the granulation chamber 1 is supported at the tip thereof. The cover] 7 prevents official materials from adhering to the nut 16 and its threaded portion, and the scraper 19 rotates along the inner wall surface of the granulation chamber l due to the rotation of the drive shaft 7, and the scraper material adheres to the wall surface. The powder material is scraped off and moved toward the center of the granulation chamber 1.

Reference numeral 20 denotes a cutting knife, which is disposed in a chamber 21 formed on the lower surface of the die 6 and the backup plate 13, and has an arm extending in the diametrical direction, which is attached to the drive shaft 7 so that its position can be adjusted in the vertical direction. It is made of thin piano wire, etc. stretched over 22 wires. The cutting knife cuts the string-like granules descending from the small hole 6 into a predetermined length. 23
is a disk for discharging granules which is arranged at the bottom of the chamber 21 and fixed to the drive shaft 7 so as to rotate together with the drive shaft 7. In addition, the rotor 10 has an axially uneven strip 24 formed on its surface in order to effectively perform the kneading and kneading of the wet material in the granulation chamber 1 and the extrusion action from the die 6. .

1 and 2 show a floor-standing type granulator in which the granulator is fixed on a frame 4, but as shown in FIG. 3, it is supported on a column 25 via a bracket 26. However, it is also possible to use a column-supported type that can be adjusted and installed at an arbitrary height position.The trench drive shaft 7 is inserted into the acid chamber 1 from above the granulation chamber 1, and the drive part is inserted into the acid chamber 1 from above the granulation chamber 1. It can also be placed above. In FIG. 3, electric phases having the same or the same functions as those in FIGS. 1 and 2 are given the same reference numerals.

In each of the above embodiments, the die 6 and the backup plate 13 are rotated together with the granulation chamber 1 while the 1llllII 7 is fixed, or the shaft 7 and the granulation chamber 1 are fixed and the die 6 and the backup plate 13 are rotated by a gear mechanism shown in the figure. The backup plate 13 is rotated and the rotor 1 is rotated by rotating the die 6.
0 may be configured to rotate on the dice 6.

The relationship among the rotor 10, the die 6, and the backup plate 13 is as shown in detail in FIG.
A small gap s(0
The hole 12 of the backup plate I3 has a diameter of at least a plurality of holes 12 to make it easier for the introduced material to be caught between the rotor 10 and the upper surface of the die 6. It is desirable that a large number of small holes 5 be formed with diameters that can be continuous with each other, and that a large number of small holes 5 corresponding to the holes 12 be formed in the die 6. Further, the dimensions are approximately equal to the thickness ti-t of the die 6 and the diameter d of the small hole 5.

This invention has the above configuration, and the drive shaft 7 is connected to the second
While rotating as shown by the arrow in the figure, a wet powder material mixed with an appropriate amount of water or binder solution is continuously fed into the particle collecting chamber 1 through the feed port 2 using a continuous feeder (not shown). . The amount and degree of input are appropriately determined depending on the granulation chamber capacity, the rotation speed of the drive shaft, the IU diameter of the granules (the diameter of the small hole 5), the physical properties of the powder material, etc.

When the wet material is introduced into the granulation chamber 1, the rotor 10, which is revolved by the drive shaft 7, rotates while biting the material between it and the die 6, and the material is crushed, ground, etc.
The material is kneaded and kneaded by applying compression and shearing action, and then press-fitted into the small hole 5 of the die 6 and extruded downward in a continuous string-like state. Cut to length. This length can be appropriately set by adjusting the position of the cutting knife 20 up and down. The granules cut by the cutting knife 20 roll on the discharge disk 23 and are discharged from the discharge port 3 in the case of FIG. 1, and are rolled on the funnel-shaped bottom of the chamber 21 and discharged from the discharge port 3 in the case of FIG. be discharged.

In the case of a conventional wet extrusion granulator, as mentioned above, the compression process and kneading process for kneading the materials are generally provided inside the granulator itself, and the wet extrusion granulator is thoroughly kneaded and kneaded. As the material is extruded from the die, the pressure applied to the material inevitably generates heat, and during long-term operation, if the allowable temperature of the material is low, it may melt or deteriorate. In a wet extrusion granulator that is equipped with a rotor that rotates and revolves within the granulation chamber, the thickness T of the die must be thick enough to withstand the force applied by the rotor. Figures A and B show the shapes of the holes.

Various shapes such as C...G are designed, and the length t of the cylindrical portion is set relative to the hole diameter d. In other words, hole A has a trumpet-shaped lower half, holes B and O have trumpet-shaped upper parts and enlarged bottoms to facilitate material introduction, and the holes have a small radius R in the material introduction part VC. Establishment, etc., CJ 2E,
Deformed holes such as F and G are bored.

However, no matter how the shape of the hole is changed, since the length t of the cylindrical part is long relative to the hole diameter d, the frictional resistance between the wet material press-fitted into the small hole of the die by the rotor and the small hole is very large. Therefore, since the die holes are easily clogged with the wet material, it is necessary to increase the wettability (amount of liquid added) of the material to improve its fluidity. The diameter of the granules is generally up to about 3z, and granules smaller than that are not manufactured. Furthermore, since the material has a high degree of wetness, the granules extruded from the small holes for granulation tend to stick together in the form of lumps.

In contrast, the present invention makes the thickness t of the die 6 approximately equal to the diameter d of the small hole 5.
The frictional resistance between the material and the wet material passing through it is much smaller than before, and the heat dissipation from the die 6 is also faster, so the wetness of the wet material extruded from the die 6 can be lowered than before. The extrusion can be carried out very easily and smoothly even at a significantly lower temperature. Furthermore, it becomes possible to produce extremely small diameter granules with a diameter of less than o, sX, which was previously considered impossible, and the processing capacity of the machine can be greatly increased. In addition, since the material extruded in strings has extremely low moisture content (low humidity), there is no adhesive bonding to each other after extrusion through the small holes, and drying is easy and quick. Therefore, the energy consumption of the drying heat source can be significantly reduced. Furthermore, the heat dissipation from the die is easy, the small holes for granulation do not get clogged, and granulation is carried out quickly, so even if granulation operation continues for a long time, the extruded material will not overheat. There is no problem such as melting or deterioration.

Furthermore, by reducing the thickness of the die, this invention allows small holes for granulation to be easily formed by press punching, etc., and there is no need to create a complicated shape as in the conventional method, which is expensive. Since the amount of special steel used is reduced to a fraction of the conventional amount, the cost is significantly reduced, and it is an inexpensive and easy-to-handle product that is highly efficient and enables granulation of significantly smaller diameter than before. A wet extrusion granulator can be provided.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of the embodiment, Fig. 2 is a plan view of the main part, Fig. 3 is a longitudinal sectional view of another embodiment, Fig. 4 is an enlarged sectional view of the main part, and Fig. 5 is the conventional It is a figure showing the shape of the die and its small hole for granulation. 1... Granulation chamber, 5... Small hole, 6. Soaking (chair, 7...
・Drive shaft, 10...rotor, 12...hole, J3...
・Backup plate, 19...Scraper, 2
0...Cutting knife applicant Fuji Paudal Co., Ltd.

Claims (4)

[Claims] (1) A die with a large number of small holes is placed in the inner bottom of a granulation chamber made of an upright cylinder, and a rotor that transfers over the die is provided inside the granulation chamber, and either the rotor or the die In a wet extrusion granulator that extrudes and granulates the official material through the small holes by rotating one side around the axis of the granulation chamber, the die is formed of a thin plate with a large number of small holes, A wet extrusion granulator characterized in that a backup plate is provided on the lower surface of the back-up plate, the back-up plate having a large number of holes having a diameter continuous to the plurality of small holes. (2) A wet extrusion granulator according to claim (1), wherein a die and a backup plate are fixed to the inner bottom of the granulation chamber, and a rotor is made to rotate and revolve on the die. (3) The wet extrusion granulator according to claim (1) or (2), wherein the small holes of the die are arranged so that the holes of the backup plate are continuous with at least a plurality of small holes of the die. (4) A wet extrusion granulator according to any one of claims (1) to (3), in which the plate thickness of the die is equal to the diameter of the small holes formed therein.