SU777374A1 - Plant for drying loose material in fluidized bed - Google Patents

Description

one

The invention relates to a drying technique and can be used in the chemical, pharmaceutical, light and other industries of the industry.

A known device for drying bulk materials in the skim; there is a layer containing a cylindrical body with a gas distribution grid and a rotor located along the axis of the body, laying, radial partitions 1.

The disadvantages of the known installation are significant dust removal and one-time use of the coolant, which reduces thermal efficiency.

The purpose of the invention is to reduce dust emission and increase thermal efficiency.

This is achieved by the fact that even partitions are shortened at the bottom and profiled at the top to form a Venturn nozzle with odd partitions, with the upper edges of even partitions interconnected by arcuate convex arches to which dampers with levers are attached above the odd partitions.

In addition, under the grating there is an additional grating with sector slits, installed with the possibility of reciprocating rotation.

FIG. 1 shows schematically the described installation, general view; in fig. 2 - view A of FIG. 1 (grates are shown once / double); in fig. 3 - view B of FIG. 1. The installation contains a cylindrical

5 housing 1, a rotor 2, and a fully perforated grid 3. Partitions are attached to the rotor 2, which have different heights and divide the working space of housing 1 into chambers. Partitions 4 (odd) are made of such a height that they lower part closely adjacent to the grid 3, and partitions 5 are shorter than partitions 4 and form a gap for the passage of the essential agent with the grid 3. The partitions 5 in the upper part are shaped in such a way that they form clamps with partitions 4 in the form of a Venturi nozzle. The baffles 4 and 5 are covered on top with semicircular arcuate convex arches 6 with hinged 7 flaps 7 which can be opened and closed by moving the levers 8. The gas distribution grid 3 has a chute 9 for discharging the dried material. In the lower part of the substance, under the gas distribution grid 3, there is an additional gas distribution grid 10 with sector slots P. The grid 10 is rigidly fixed to the shaft 12 on the shaft 12.

The material is loaded through the nozzle 13, and the exhaust coolant is discharged through the nozzle 14.

The installation works as follows.

The material to be dried is continuously fed through the side nozzle 13 into the chamber, where it is captured by partitions 4 and 5 and is moved by the rotation of the rotor 2 through the drying zone B. A drying agent is supplied to the lower part of the installation through the gas distribution grids 3 and 10, which is also fluidizing. To avoid stagnation zones in the layer of dried material, the grille 10 is driven by shaft 12 in a reciprocating rotational motion, thereby ensuring alternate fluidization of the total volume of material in the housing 1. As the rotor 2 rotates, the flaps 7 alternate between the unloading zones G and loading D, then open (zone B), as a result of which the drying agent successively passes all the chambers towards the moving material and is discharged through the nozzle 14. The closing of the shutters 7 prevents the release of unused annogo drying agent and contacting the exhaust moist drying agent with the dry material. In the constrictions having the form of venturi nozzles, the drying agent is accelerated and enters the chamber with the material at high speed. Due to the fact that the partitions 5 are shorter than the partitions 4, the drying agent seamlessly passes from the chamber to the chamber through the gap formed between the partitions 5 and the grid 3. The number of partitions of the rotor can be any, but not less than four. Otherwise, it is possible to mix dry material with wet material.

The use of the described installation in the industry will provide a number of advantages. In the installation, even with a developed fluidization regime, the ablation of material is almost eliminated (0.2-0.5% versus 20-30% in the known installation 1) due to the fact that the drying agent consistently passes from chamber to chamber from dry to wet material, ensuring adhesion of dry to wet. The use of an additional gas distribution grid 10 allows several times to reduce the operating speeds of the drying agent, since the material liquefaction occurs not over the entire volume of the material, but over a certain amount

Its portion located above the lattice slots 11. The liquefaction of the entire material occurs due to the displacement of the sector lattice 10. The drying agent, accelerating in the Venturi nozzles, moves in countercurrent with the drying agent entering through the lattice 3 - this greatly reduces the entrainment of material while increasing the uniformity of the layers. In the installation, it is possible to more fully use the heat of the drying agent, since the latter passes all the chambers successively, for this reason the material is not subject to sharp temperature fluctuations, but is dried evenly, therefore the installation with

can be successfully used for drying heat-sensitive, easily cracking materials. , It is also easy to adjust the degree of moisture extraction, changing the speed of rotation of the rotor 2. In the installation

the formation of stagnant zones is excluded, which makes it possible to more fully use its volume and carry out processes of fine chemical technology. It should also be noted that, along with insignificant ablation and abrasion (due to the soft hydrodynamic setting), an insignificant level of static electricity is observed in the installation, which allows it to be used for drying fire-explosive materials.

Claims (2)

1.Installation for drying bulk materials in a fluidized bed, comprising a cylindrical housing with a gas distribution grid and a rotor located along the axis of the housing carrying radial partitions, in order to reduce the dustiness and increase thermal efficiency, even partitions are shortened at the bottom and shaped at the top to form, together with odd partitions, pinch in the form of a Venturi nozzle, with the upper edges of the even partitions interconnected by arcuate convex arches to which the dampers with levers are attached above the odd partitions. 2. The installation according to claim 1, characterized in that an additional grating with sector slits is placed under the grate and is installed with the possibility of returning rotational motion. Sources of information taken into account in the examination 1. USSR author's certificate No. 151249, cl. F 26B 17/10, 1960.