RU2002522C1 - Device for separation of loose materials - Google Patents

Description

The invention relates to air (gas) separation of bulk materials into fractions with particles of fineness, mainly in the range from 20 to 300 microns, and can be used in chemical, metallurgical, food and other industries.

As is known, the task of devices for separating bulk materials is to obtain conditioned fractions without contaminating them with larger particles and a high yield of the finely divided product.

The tendencies in the development of fractionation of bulk materials in air flows are characterized by the fact that by creating favorable aerodynamic conditions in the apparatuses it is possible to obtain fractions of material in relatively simple structures without contaminating them with particles of other sizes. It is in this case that the high quality of products obtained by powder technology is ensured.

In this regard, among devices for separation of both gravitational and inertial types, devices with axisymmetric material output are increasingly used. In them, it is possible to more carefully distribute not only the dispersed dispersible, but also the air medium over the cross section, which leads to a more complete use of the device capacity, a decrease in the volume concentration of the material, and better separation.

A device is known for separating bulk materials into fractions, comprising a housing 1 with a fine fraction collector, a pipe 3 located along the axis of the separation channel 8 in its upper part for supplying the starting material and in the direction of the action of gravitational forces, mounted on it above the upper separation layer the channel, the deflecting cone 7 and the suction pipe of the air stream with fine fractions 4. In the lower part of the separation channel above the collector of coarse fractions 12, a grill 9 is installed.

The separation is carried out as follows.

The feed is fed through a pipe located along the axis of the separation channel. Falling into the ascending air stream, fine particles whose whirling velocity is less than the velocity of the ascending stream are introduced into the upper part of the separation channel, where as a result of a drop in the flow velocity (below 0.1 m / s) they are deposited. Large particles.

moving down the separation channel, fall into the collection 12.

Noting the dignity of the device in question associated with the organization

of the material supply process, it should be noted that obtaining in this apparatus a high-quality finished finely dispersed product is very problematic.

This is primarily due to the summing up of the finely dispersed particles themselves in the streams, namely, their increased aggregation ability, the essence of which is the adhesion of fine particles into larger formations,

5 A device for separating materials is known (see aut. St. USSR No. 1240472, class B 07 B 4/08, 1986), including a cylindrical body 1, a separation channel 2, a nozzle 3 for supplying a shared medium, mounted along the axis of the housing , gas distribution grill 4, gas supply chamber 5, gas flow rate regulator in the form of an annular element 6, unloading device 7, outlet pipe

5 large product 8, a nozzle for supplying a separation medium 9, a nozzle 10 for withdrawing this medium with fine fractions.

The device operates as follows.

0 The source material enters the grate 4 through the nozzle 3. Through the nozzle 9, air is supplied into the chamber 5, under the influence of which a fluidized bed is created on the grate 4.

5From this layer to separation channel 2

fine particles as well as particles of intermediate size are blown out.

The largest from the lattice enter the unloading device 7 and then through

0 pipe 8 the output of the vehicle from the device. Particles of intermediate particle size also enter there after separation in the separation channel 2. Fine fractions are removed from the apparatus through the nozzle 10

5

Despite the indicated improvement in the dispersion of the material after the impact on the solution4, and the rapid removal of large particles in the future by gravitational separation, aggregation of fine particles and their adhesion to large ones are carried out, since there is no provision for the rapid separation of fine particles immediately after the impact. The phenomenon of aggregation is observed throughout separation channel 2. since the mass forces here are relatively weak gravity forces. An increase in the speed of the separation medium leads to a sharp contamination of fine fractions by large particles.

In addition, the existence of a fluidized bed above the grating disrupts the flow structure and causes even greater turbulence in the separation channel (especially in the initial section), as a result of which the particles participate in the circulation movement. All this leads to an increase in mass concentration in the separation channel and the interaction of the particles with each other, which worsens the conditions of separation, and therefore the quality of the finished thin product (see Schreiber-A.A., Mitotin V.N., Yatsenko V., P. Hydromechanics bicomponent flows in a solid polydisperse substance. K, Science. Dumka. 1980, p. 252).

This device, as the closest in technical essence to the proposed one, was adopted as a prototype.

The aim of the invention is to reduce the contamination of fine fractions with coarse particles.

This is achieved by the fact that in the device for separating bulk materials, comprising a housing with a collector of large particles in its lower part, a nozzle for inputting the initial mixture, mounted coaxially to the housing in its upper part with an output end facing the collector of large particles, a grate and the gas outlet pipe and fine fractions located in the upper part of the casing, the grill is installed on the input pipe of the initial mixture between its outlet end and the gas outlet pipe with thin fractions, the ratio diameter Lattice openings to the inner diameter of the tube entering the initial mixture of 0.1 - 0.3.

The drawing shows a General view of the proposed device.

The device includes a housing 1 with a collector 2 of large particles in its lower part, a nozzle 3 for introducing the initial mixture, mounted coaxially to the housing 1 in its upper part with an outlet end 4 facing the collector 2 of large particles, a gas outlet pipe 5 with fine fractions, located in the upper part of the housing I, and the grill b placed in the housing, mounted on the nozzle 3 for inputting the initial mixture between its outlet end A and the gas outlet pipe 5 with fine fractions, while the ratio of the diameter of the holes of the grate 6 to the inner diameter of the nozzle 3 input of the initial mixture of 0.1 to 0.3.

The device operates as follows.

The initial mixture, together with air (gas), is supplied to the inlet pipe 3 of the initial mixture, accelerates there and is thrown into the internal volume of the housing 1. Formed with a dusty air stream when moving downward, it encounters aerodynamic resistance of the air volume and the lower part of the housing 1. Large particles. 5, having a large inertia, they maintain a rectilinear downward motion of the housing 1 directed along the axis. Having overcome the aerodynamic drag of the air volume, they are quickly discharged to the coarse particles collector 0 2.

In case 1, the jet of the dust-air mixture decelerates, where due to different inertia of the gas and particles, air from the jet begins to rise, passing through lattice b and entraining fine particles, the inertia of which is much less than the inertia of large particles that follow down into the collector 2.

In the proposed device, as well as in the prototype, finely dispersed aluminum powder of the ASD-T grade (GOST 5.1667-2), finely dispersed titanium powder (GOST 14086-68) and iron powder (GOST 9849- 74). The particle size of these materials is from 0.1 - 1000 microns.

The presence of a lattice installed on the input pipe of the initial mixture between its

The output end and the branch pipe for the removal of gas with fine fractions can increase the degree of extraction of fm of fine fractions into the product of the same name and reduce the degree of their contamination of km with large particles. Moreover, the location of the grating in this section has practically no effect on the separation process, in contrast to the case when the grating is located below the outlet end of the inlet of the medium to be separated.

0 Instead, for each cell size of the quenching turbulent pulsations of the lattice, there is an optimal value at which its efficiency is greatest. In this regard, the sizes of the lattice cells changed by 5 li over a wide range of 0.2-5 mm.

The highest separation efficiency, and therefore, the least degree of contamination of the fine fractions with coarse particles for sedimentation of materials, calculated

0 as the difference between the recovery of a thin product and its contamination.

Em FM- Km,%

5 occurs in the range of the ratio of the diameter of the grating aperture dp to the inner diameter of the inlet pipe of the initial mixture dn equal to 0.1 -0.3. With this relationship, the maximum and constant efficiency of the Em separation process is achieved.

720025228

Thank you for reducing the degree of contamination of the mixture relative to the gas outlet pipe with

fine fractions by large particles, fine fractions),

high quality of the final product is achieved. This ultimately allows the product to be finished. This is the quality of the products that will be manufactured as a Quality Indicator. In this case, 5 are made from the resulting thin product.

The degree of contamination of the fine km to exclude the costs of implementing the product in large, particles. Re-purification of a thin product from the group of the proposed device, the indicator Km of non-specific particles, as well as reduce overall

exceeds 5%, while for the proto-dimensions of the device itself,

pa this indicator varies within 10 9

from 0 to 23% (depending on location (56) Copyright certificate of the USSR

output end of the input branch pipe of the input No. 1240472, class B 07 B 4/08, 1986.

Claims (1)

The claims 15 laid in the upper part of the housing, characterized in that. In order to improve the separation of the separation efficiency of the FUEL MATERIALS, including reducing pollution by a fine fraction of pus with a collection of large particles in its coarse particles, the grill is installed at the bottom, the input port 20 of the input mixture on the input port of the initial mixture between the mixture mounted coaxially with the housing in its outlet end and the outlet pipe1 of its upper part with outlet end, thin gas fractions, while facing the collector of large particles, stitching the diameter of the grating openings to the inside t is the grill housed in the casing and the diameter of the inlet pipe of the inlet side of the gas outlet with fine fractions, the initial mixture is 25 - 0.1 - 0.3.