SU1219894A1 - Installation for drying and grinding loose materials - Google Patents

Description

This invention relates to a technique for drying bulk materials while grinding them and may find application in the chemical and other industries.

The aim of the invention is to increase productivity.

FIG. Figure 1 shows schematically an installation for drying and grinding bulk materials; in fig. 2 shows section A-A in FIG. one.

The installation contains a vertical conical drying chamber 1, a stirring, with an annular gap 2 in it, a cyclone chamber 3 with an inlet tangential fitting 4, a loading device 5 and an axial pipe 6 having an outlet nozzle 7, a swirler 8, a discharge pipe 9, a cyclone 10 , additional tangential pipe 11, circulation circuit 12 with a mill 13 and a heater 14.

The installation works as follows.

The initial wet material is loaded through the loading device 5 into the cyclone chamber 3, where the product is dried due to hot air entering through the inlet tangential fitting 4, as well as additional heat supply due to heat transfer from the wall of the axial tube 6 to the rotating air suspension flow.

Under the action of centrifugal force arising due to the rotational motion of the gas, the material moves along the walls of the cyclone chamber 3 in the mode of a downward swirling flow. Simultaneously with the removal of moisture surfaces, intense abrasion of particles of material occurs, which leads to an increase in the interfacial surface and an increase in the rate of heat and mass transfer. At the exit from the cyclone chamber 3, the coolant (air) changes its direction and moves upwards. As a result

this occurs inertial separation. Dust particles present in the initial wet material as an air suspension, as well as newly formed during the abrasion process and representing the product

the product is carried through the swirler 8 into the annular gap 2. Large particles under the force of gravity enter the circulation loop 12 and, picked up by the additional coolant flowing

from the exit nozzle 7, enter the mill 13. The use of the nozzle 7 is dictated by the need to create a minimum vacuum in the circulation circuit 12 to improve the evacuation conditions) 1 particles from the bottom of chamber 1. In the mill

13, the material is crushed to the required dispersion, after which the air suspension flow in the pneumatic transport mode is directed to the annular gap 2 through an additional tangential nozzle 11. As a result, an upward swirling flow of solid particles is formed in the annular gap 2, where the final drying of the material takes place. Thereafter, the material is carried by air flow into the cyclone 10.

In order to carry out the deep drying of the dust particles in the chamber 1, a vortex layer of suspended material can be created. At the same time, the required residence time of particles in the layer is achieved by installing screw partitions of a swirler 8 with geometrical parameters (angle of inclination, area of free section between partitions and their number), providing such a tangential flow rate of the heat carrier at which a vortex layer of suspended particles is formed. In case of a lack of heat entering the chamber 1, it is advisable to install a heater 14 inside the annular gap 2.

Editor A. Vorovich Order 1312/48

Compiled by A. Iron

Tehred I. VeresKorrektor L. Pilipenko

Circulation 635 Subscription

VNIIPI USSR State Committee

for inventions and discoveries

113035, Moscow, Zh-35, Raushsk nab. 4/5

Branch PPP "Patent, Uzhgorod, st. Project, 4

Claims (2)

1. INSTALLATION FOR DRYING AND GRINDING OF BULK MATERIALS, containing a vertical conical drying chamber, a cyclone chamber moist with an annular gap, with an inlet tangential fitting and a loading device in the upper part and an axial tube, the drying chamber being connected in the upper part to the discharge pipe, and in the lower - to the mill, characterized in that, in order to increase productivity, it additionally contains a swirler installed in the lower part of the annular gap connected in the zone above an eddy rotator with a mill with a pipe connected tangentially to the annular gap, and the axial pipe at the outlet has a nozzle located at its outlet end face at the level of the lower edge of the drying chamber. 2. Installation according to π. 1, characterized in that in the annular gap an additional heater is installed. Heated ones plow->