SU860855A1 - Granulator - Google Patents

Description

one

The invention relates to equipment for the production of granules from powdered materials of roller compaction, preferably for the production of granules from fine powders.

A device for producing granules is known, containing; its two counter-vras, ayush, their rolls, on the outer surface of which there are cells, tubes for supplying liquid to the roll cells, in the pressing zone to form a film, when the evaporation of which cleaves the granules, vibrating screen (or screen) for cleaning the grappules from the compressed tape and powder and the hopper that feeds, rolls, into which the initial powder is loaded, as well as the remaining powder from the vibrating screen with special suction. The granules formed in the roll cells are pushed out of the pockets by the action of liquid evaporation, which can occur from the liquid matrices with heated rollers (one method), from contact of the liquid with the heated, initial powder, aluminum hydroxide, which can be heated to 350 ° (second method),, and from the combined effect of the first and second methods 1.

The disadvantages of this device are: the difficulty of releasing the formed granules from the pockets of the rolls and the low reliability due to the fact that the ejection force from the evaporated liquid may be small and it is not adjustable; the need for drying (calcining) obtained

5 granules to remove the liquid after rolling and harden them; during the rolling of the powder, not only the granules in the roll cells are pressed, but the tape across the width of the rolls on the surface,

10 where there are no cells (between them) connecting the granules into a single continuous strip. A vibrating screen is used to free the pellets from the tape. At the same time, on the sides of the granules there is still a part of the ribbon in the form of a skus of small height (the compacted leite has no less durability than the granule itself), besides the granules can be partially destroyed, which is their quality.

Known granl tor of powdered materials containing a hopper, two hollow rolls, rotating pavtrechu each other and having on the outer

25 of the cell surface, communicating with the roll cavities, a means for removing granules from the roll cells, including inserts of elastic material disposed in the cells, a compressed gas system, iodine connection 30 to the cavities of the roll 2.

When granulating fine powders, low-strength granules are obtained on this device. In addition, it is necessary to use injection devices to force the powder into the roll nipple area or pretreatment of the powder is necessary, for example, moistening, so that it enters the pressed zone by its own weight. .

In addition, the deficiency of the known device consists in the low yield of high-quality granules, since during rolling up on the surface of the rolls not only granules are formed, but also "tape ps" across the entire width of the rolls, binding the granules into a single continuous strip. Crushing and screening is required to free the granules from the tape, as well as to clean the spills from the powder. After release from the ribbon on the lateral sides of the pellets 0; one hundred {mars. Uneven in height, equal in height to the ribbons, and also possible partial pellets. ;; The purpose of istegy is to build up the granules from fine powders and to create good quality wounds. This is achieved by the means for removing the granules from the rolls cells; the perforated ring made of gas-tight material with holes coaxial cells in each roll is mixed; roll, a layer of porous material, placed between the roll and the ring and coagulated with them, and a vacuum system connected to the roll cavity.

FIG. 1 shows a cross section of a granulator; in fig. 2 is a top view of the forming rolls; “And FIG. 3 shows the node I in FIG. one.

The device consists of a loading hopper 1 filled with powder, and a pair of counter-rotating rolls of spring-loaded rolls 2 and 3.

On the outer surface of the rolls are the cells 4. Inside the rolls are perforated rings 5 and 6, with holes 7 coaxially with the cells 4; between rolls 2 and 3 and rings. and 5 and 6 is located loy 8 of porous material, for example, of porous metal. Ceramic material. The thickness of the rolls 2 and 3 depends on the height of the granules and may be more than half. our heights are granules. The remaining part of the height of the granule (one half of the height of the granule), the bottom of the granule, is placed on the middle layer 8. The thickness of the middle layer 8 can be equal to the height of the bottom of the granule increased by 10-15 mm, and the total height is determined by the strength of the middle layer (per cm), depending on the effort to suppress air, as well as on the ability to pass air through the porous metal-ceramic material from which the middle layer is made. Since the thickness of the roll and the layer of porous material is mostly crowded by a crowd of different granules, they cannot bear heavy loads, and therefore they cannot bear the main load of the pressing force, rings 5 and 6, the thickness of which is determined only by the pressing force.

Supporting shafts 9 and 10 and. Have holes

10 and 12, to which a compressed gas system and a vacuum system are connected to a switchgear (not shown). In zone B, a normal pressure is created, in zone B, a vacuum is created, and in zone D, increased pressure is a discharge zone (for example, 4-6 atm, if air is supplied from a common line). The rolls 2 and 3 are pressed against each other by springs 13 mounted on the pushers 14 housed in the guide cages 15 and 16.

The device works as follows.

The initial powder from the feed hopper 1 is fed into the inter-roll space, to the bottom of the vacuum, and the powder is drained into the cells of the four rolls, fills them and, when the rolls rotate, is pressed into the granules 17. The discharge zone, G, is formed zeros 17 are pushed out of the cells 4 rolls by air pressure. In the discharge zone F, the regeneration of the middle porous layer 8 of the agglomerated powder also takes place, and the zone D can be increased at the expense of the normal pressure zone B up to excluding it, if necessary, to enhance the regeneration of the middle layer. By creating the necessary pressure in the injection zone D, it is possible to provide an absolutely reliable exit of the formed granules from cells 4. By regulating the dilution force in zone C, and by its area (for example, increasing zone D due to the zone of normal pressure B), it is possible to ensure the necessary filling capacity of the cells 4 , and the regulator is pressed with the force by pressing the rolls with the springs 13, it is possible to ensure the required density of the granules.

 the fact that the powder under the action

The rarefaction force Q will be drawn only into the cells 4, but not all of the float1, adi rolls (air can pass only through the porous metalloceram. The middle layer 8, open at the top of the diameter of the cells 4 valgov KOV 2 and 3, the powder is drawn, only due to suction, because under its own weight the powder will not go into the millboard space due to its fine dispersion and low bulk weight - for which a special injection feeder is needed, for example, in the form of a screw screw placed in the bunker 1), only granules will be formed during rolling,without compressed tape. As a result, the granules will come out with

a clean outer surface that does not require further processing (a thin layer on some granules at the junction of the roll cells at the time of pressing can be easily removed, for example by agitating the granules and sieving, without compromising the integrity of the granules).

Claims (2)

1. US Patent No. 2729855, cl. 264-109, publ. 1956 2. Japan patent No. 49-49291, cl. At 30 В 11/16, published 1974 (prototype).