SU252292A1 - Drum vacuum filter - Google Patents

Abstract

1. A drum vacuum filter consisting of a rotating drum divided into a series of cells with channels connected to a distribution device, including moving and stationary parts with holes, troughs with a slurry, agitators and a device for removing sediment, characterized in that In order to increase the filter capacity and to provide liquid regeneration of the filtering material, the fixed part of the distribution device has an overflow channel for evacuating the filtrate from the cell to the cell and a chamber for communicating the cell with the cell. with the atmosphere.

Description

l (mnoc f8fHUU air

(L

to eat

Hche

to

with to

C f amttu tojdyjt

2. Drum vacuum filter on n.l, which is similar to the fact that, in order to regenerate the filter252292

material during deep immersion of the drum in suspension, the drum cells are provided with accumulative pockets.

This invention relates to devices for separating a suspension into liquid and solid phases.

Drum vacuum filters are known, consisting of a rotating drum immersed in a suspension, the cylindrical surface of which is covered with a filtering medium (filter fabric: other filtering materials and circumferentially divided into a plurality of cells; a trough with a suspension to be filtered, in which the agitator is installed mixing the suspension; a device for removing the sediment from the drum; a distribution device consisting of movable and fixed parts, lapped and pressed to each other by end faces .

The movable part of the dispenser is fixed to the end of the drum and rotates with it. It has openings, each of which is connected by channels with a corresponding cell of the drum. The fixed part is an annular box divided into a number of individual chambers, of which one communicates with a vacuum, the others with compressed air.

However, despite the large inflation zone and a small regeneration zone, their average productivity is significantly lower than the initial performance and drops sharply with the filter operation time, since blowing with compressed air does not ensure complete regeneration of the filtering medium. Compressed air does not blow small capillaries, but passes only through large capillaries a filter of lean material, without removing from the irregularities of the walls of the capillaries individual particles of the solid phase held by surface tension forces. As a result, these capillaries are clogged, which leads to an increased consumption of filter material.

A continuous drum vacuum filter with regeneration of the filtering medium by reverse flow of a liquid with an increased filtration zone is proposed by reducing the regeneration zone.

In the proposed vacuum filter, each cell has an accumulation pocket and at least two channels, one of which serves to fill the cell with liquid and the other to evacuate the air from the cell at the time the cell is immersed in the suspension and, accordingly, to fill the cell with air, and for evacuating the fluid as the cell leaves the suspension. The distribution device has an overflow channel for communicating the cell coming out of the slurry, with the cell being immersed in the slurry. This results in the fact that the regeneration zone is located immediately after the cell is immersed in the suspension and occupies an insignificant part of the immersion angle of the drum in the suspension, and the filtration zone itself expands significantly.

FIG. Figure 1 shows the proposed deep-well drum vacuum filter with liquid regeneration of filter material; in fig. 2 is a schematic drawing showing the overflow of the filtrate from the cell leaving the immersion (position a) into the cell loaded into the suspension (position 6); in fig. 3 - cell in the position of p. generation of filtering material (position B) and a cell located in the filtration zone, filled with filtrate (position g). i

The proposed vacuum filter consists of a drum 1, circumferentially divided into a plurality of cells 2, troughs 3 for slurry, meigalki 4, a device for removing sediment 5 and a distributor 6 such as a rotating spool. 32 The drum has openings on the outer cylindrical surface and is covered with a filtering medium, for example a filter cloth, or another filtering material. Each cell passing along the drum has at least two channels, one of which 7 is located at the front wall of the cell (as the drum rotates) and the other 8 at the back wall of the cell. Channels 7 and 8 are connected to distribution device 6. The cavity of the cell and channels serves as a reservoir for accumulating the filtrate in such a quantity that it is sufficient to regenerate the filtering medium by pushing it into the trough, as well as a hydraulic lock for compressed air that forces the accumulated filtrate. In the case of a deep-dip filter, in order to provide a reliable water seal, each cell has a special accumulation pocket 9. The distribution device 6 consists of moving and fixed parts, lapped and pressed against each other by the front sides. The movable part is fixed on the end part of the drum and rotates with it. It has two concentric rows of holes, the number of which in each row is equal to the number of cells. The holes of one row are connected to the channels 7, and the holes of the other row are connected to the channels 8. The fixed part of the distribution device has a chamber 10 connected to the vacuum line for filtration, a chamber 11 connected to the vacuum line to wash the filtered sludge, chamber 12 , combined with a compressed air line, for regeneration, chamber 13 communicating with the atmosphere through the control valve 14, and overflow channel 15. Channel 15 is located in such a way that its one end is located opposite to one concentric row of holes the movable part of the switchgear, and the other opposite the other concentric row of holes, and connects the channels 8 of each cell coming out of the slurry with the channels 7 of each submerged cell. The chambers of the unsuitable part of the switchgear are separated by bridges that are so shaped that they can block the channel 8 of each cell when it leaves the suspension to ensure the filtration of the filtrate, as well as the channel 7 in the regeneration zone of the filtering medium. The vacuum filter works as follows. The filter drum rotates around a horizontal axis. In this case, the movable part of the switchgear, fixed on the end of the drum, turning relative to the fixed part, communicates each cell of the drum with all the cameras of the switchgear sequentially. As a consequence, each cell passes successively in the zones of filtration, overflow of the filtrate, washing, drying and removal of sediment, overflow of the filtrate and regeneration of the filter cloth. For example, in the filtration area itself, the cell is connected by canadia 7 and 8 with a vacuum chamber 10. In this case, the filtrate is removed from the vacuum filter. Before exiting the suspension (position d), channel 8 overlaps, and the filtrate from the cell is withdrawn only through channel 7. This ensures that a portion of the filtrate is retained in cell 2 and the collection pocket 9. As soon as the cell leaves the suspension (position a), channel 7 is reported through the chamber 13 with the atmosphere, and the channel 8 with the overflow channel 15, which through the cell, immersed in the suspension, is connected to a vacuum. Due to the created pressure drop in channels 7 and 8, the filtrate is quickly evacuated, and the cell is filled with air. Moreover, the air in the cell has a pressure slightly below atmospheric, because it enters through a control valve. This ensures that the sediment is kept on the surface of the drum. After passing through the washing, drying and discharging zones, the cell is immersed in the suspension (position 6). At this point, channel 8 communicates with the vacuum chamber 10, through which air is removed from the cell and vacuum is created in the cell, and channel 7 communicates with the overflow channel 15,

which communicates with the cell coming out of the suspension (position a) and filled with filtrate. The filter is quickly filled with the filtrate of the cell in position b. The cell is ready for regeneration of the filtering material and then communicates with the compressed air chamber 12 of the distribution device (position S). Regeneration is done

Vacuum

Atmospheric air.

forcing the filtrate with compressed air through the filter material in the filter trough.

After regeneration of the filter cloth, the actual filtration begins, and the cycle of operation is repeated. Due to the fact that the drum is divided into many cells, working on the described cycle, the filter operates continuously.

Claims (2)

1. A vacuum drum filter, consisting of a rotating drum, divided into a number of cells with channels connected to a switchgear, including a movable and fixed part with holes, a trough with a suspension, a mixer and a device for removing sediment, characterized in that, with In order to increase the filter performance and ensure liquid regeneration of the filter material, the fixed part of the switchgear has an overflow channel for evacuating the filtrate from cell to cell and a chamber for communicating with the atmosphere. • Pui.l 2, The drum vacuum filter according to claim 1, is unique in that, in order to regenerate the filtering material when the drum is deeply immersed in the suspension, the drum cells are equipped with storage pockets.