SU1273192A1 - Pneumatic separator - Google Patents

Description

The invention relates to the chemical and related industries, as well as to agriculture, in particular to the processes of classification of particulate matter.

The purpose of the invention is to improve the quality of separation of granular materials by eliminating the downward movement of the upper separation product in the lower discharge zone.

In FIG. 1 shows a pneumatic separator, a longitudinal section; in FIG. 2 a section AA in FIG. 1.

The pneumatic separator includes a housing 1, a distribution grid 2, unloading units 3 of the upper and lower separation products, the latter being made in the form of pockets 4 with outlet windows 5 mounted on the wall of the pneumatic separator housing, as well as a collection header 6 of the lower product,. to the distribution grid and the fluidizing agent supply device 8 under the grid 2,

Pneumoseparator works as follows.

The source material is loaded at one end. The fluidizing agent enters the apparatus through the distribution grid 2 and fluidizes the granular material. As the fluidized material moves along the separator to the unloading zone of the target products, it is separated. Large (heavy) particles accumulate at the bottom, enter the pockets 4, passing through the gaps between their lower ends and the distribution grill, and are unloaded using the windows 5 into the collector 6. The upper product is discharged in one place using the unloading unit 3.

The use of delocalized unloading of the lower product with the help of several pockets allows to reduce the speed of the downward movement of solid material in the place of unloading and to avoid the ingress of small (light) particles into the lower product.

Example. A binary mixture of narrow quartz sand fractions was separated with solid particles 6, = 0.200-0,250 mm and d ₂ = 0,3150,355 mm (the fine fraction in the mixture was 33%). The fluidized bed separator (Fig. 1) had a cross section of 470x31 mm.

192 2

As a distribution grid, two layers of filter cloth were used. Three U-shaped pockets with a cross section of 15x15 mm were installed along the side wall of the separator at a distance of 15 mm from each other. The gap between the lower ends of the pockets and the distribution grid was 3-5 mm. The target products were discharged through nozzles mounted on the wall of the separator and subjected to sieve analysis in order to determine their particle size distribution.

The velocity of the fluidizing agent (air) was 0.12 m / s, the performance of the classifier according to the initial mixture was 7.5 kg / h; on the bottom product - 5 kg / h.

Unloading the bottom product was carried out using one (localized unloading), two or three pockets. To obtain comparative data with a known technical solution, the mixture was also separated under the same conditions with a localized removal of a large fraction directly from the bottom of the fluidized bed through a pipe installed on the wall of the separator under the place of unloading of the top product.

The results of comparative tests are presented in the table.

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Directly below the layer .1 20

With the help of tear-thieves |

Localized

unloading 1 12 Delocalized Unloading 2 7.2 Also 3 . -515

Claims (1)

1 The invention relates to chemical and related industrial fields, as well as to agriculture. in particular to the process of classification of solid particles. The purpose of the invention is to increase the quality of separation of granular materials by eliminating the descent of its upper separation product in the lower discharge zone. Fig, 1 shows a pneumatic separator, a longitudinal section; FIG. 2, section A-A in FIG. 1. Pneumatic separator includes case 1, distribution grid 2, unloading units 3 for the upper and lower separation products, the latter being made in the form of pockets 4 with water windows 5 installed on the wall of the pneumatic separator body, as well as a collector for the lower product, node 7, the supply of the source material to the distribution grid and the supply device 8 for the liquefaction agent under the grid 2. The pneumatic separator works as follows. The source material is loaded at one end. The fluidizing agent enters the apparatus through the distribution grid 2 and fluidizes the granular material. As the fluidized material progresses along the separator to the discharge zone of the target products, it separates. Large (heavy) particles accumulate at the bottom, enter the pockets 4, pass through the gaps between their lower ends and the distribution grid, and are unloaded via windows 5 into the collecting manifold 6. The upper product is discharged in one place using the discharge unit 3 Use the delocalized unloading of the lower product with several pockets allows to reduce the speed of the downward movement of the solid material at the unloading site and to avoid small particles (light particles in the lower product. Example. Conducted separation of the binary mixtures of narrow fractions of quartz sand with sizes of solid particles d, 0.200-0.250 N04 and 3I50,355 mm (the content of the fine fraction in the mixture was 33%), the fluidized bed separator (Fig. 1) had a cross section of 470x31 mm. 922 Two layers of filter cloth were used as a distribution grid, three U-shaped pockets with a cross section of 15x15 mm were installed along the side wall of the separator 15 mm apart. The gap between the lower ends of the pockets and the distribution grid was 3-5 mm. The target products were discharged through the pipes installed on the separator wall and subjected to sieve analysis to determine their particle size distribution. The speed of the waiting agent (air) was 0.12 m / s, the performance of the classifier for the initial mixture was 7.5 kg / h; on the bottom product - 5 kg / h. The bottom product was unloaded using one (local unloading), two or three pockets. To obtain comparative data with a known technical solution, this mixture was also separated under the same conditions with localized removal of a large fraction directly from the bottom of the fluidized bed through a pipe installed on the separator wall under the top product discharge point. The results of the comparative tests are presented in the table. Directly from the bottom of layer 1 using a layer Localized unloading I Delocalized unloading 2 Same 3 Invention that, in order to improve the quality of separation of granular materials due to 2731924 elimination of the downward movement of the upper separation product in the zone of dumping, and the discharge unit of the lower separation product is made in the form of 5 vertical pockets installed on the inner wall of the housing with a gap above the distribution grid and facing to it with open ends. FIG. 2 H If ft / / I .) fr Ljl  // f 555