RU2005120C1 - Apparatus for dewatering suspension - Google Patents

Description

the filtration cycle is repeated, feeding the initial cellulose suspension to thicken at a rate of 15 m3 / s.

Example 2. A wastewater sludge obtained after centrifugation during the treatment of domestic and industrial effluents at the aeration stage of Beliy Island is fed into the device (Fig. 3) through the nozzle 2. The moisture content of the precipitate is 87%. The pressure created in the upper chamber above the suspension is 40 MPa. The thickening of the suspension occurs due to the separation of the liquid (Fig. 4) through the pores formed by the set of plates 11 with RZ equal to 200, freely mounted on the hollow perforated fingers 6, which, in turn, are freely placed in the sieve holes 5. The feed rate of the initial suspension 40 m3 / h A condensed sewage sludge with a moisture content of 62% is continuously collected through the discharge pipe. After 25 minutes of operation of the device, a drop in feed rate to 21 m / h is observed. After stopping the supply of the initial suspension and taking out a significant part of the condensed sludge, the filter element is rotated 180 ° around the horizontal axis. This leads to the fact that the lower part of the sieve surface with the corresponding ends of the fingers 7, equipped with a set of plates 11, goes into the upper position of the chamber 9. The fingers with the set of plates fall under their own t plate until they fit onto the sieve surface with RZ equal to 200, clean thereby a sieve hole. In this case, that part of the fingers with the plates, which previously occupied the upper position (chamber 9), will be located in the lower chamber 10. The filtering capacity in the gaps between the plates is regenerated in the upper chamber 9 by clean water entering it for 5 minutes. After this, the cycle of work is repeated.

After 20-25 minutes of operation of the device, the regeneration cycle is repeated: the fingers with the plates located in the chamber 10 will again occupy the position for their regeneration and work in the chamber 9,

The use of this device for thickening sewage sludge, the filter elements of which have different roughness, are presented in example 3,

PRI me R 3 (a, b, c.d). Under the conditions of Example 2, surfaces with a roughness RZ of 0.1: 100: 250 were used to thicken the sewage sludge with a humidity of 87% at a pressure of 38 MPa; 320. Feed rate

sludge for dehydration 40 m / h. G "; Ultras for the dewatering of sewage sludge and the regeneration time of the filter surface with varying degrees of roughness 5 are shown in the table below. It can be seen from the latter that, under the same conditions, the operating time of the filter up to a 50% drop in its performance depends on the value of Rz. This dependence can be easily illustrated by filtering a finely dispersed suspension through a Schott filter. It is known that the Schott filter Ns 1, having the largest pores in a glass porous plate serving as a filter, is quickly clogged by particles of the dispersed phase. In the case of filter No. 4, very fine pores, filtration is observed several times longer. Therefore, in this case, the higher the class

0 roughness, the thinner the pores are formed and the longer the filter works without regeneration. In addition, the data in the table show that the regeneration time in the case of a high roughness class is shorter. The latter is explained by the fact that thin pores are mostly blocked from the surface and therefore, when backwashed, they are easily opened (cleaned). In wider pores, clogging occurs throughout

0 their length, which reduces the efficiency of their regeneration. A decrease in the time of dewatering of the initial sludge at a 50% drop in productivity is accompanied by obtaining a dehydrated sludge with different

5 humidity. The minimum moisture content of the sediment at R7., Equal to 320. However, with the indicated roughness, the filter operating time is significantly reduced, while the regeneration time is increased in comparison with examples 2 and Sv.

PRI me R 4 (prototype). Sewage sludge, humidity 87% at a pressure of 38 MPa, is fed into the chamber.

Volumetric feed rate - 40 m3 / hour.

5 Drop in performance up to 50%

from the original was noted after 40 minutes.

The moisture content of the precipitate is 67%. By reducing the regeneration time of the filter element, the productivity of the device is increased. In addition, the cost of drying the sludge having a moisture content of 62-66% after dewatering the suspension on Lredl - is reduced.

5 to the desired device, while according to existing technology the humidity is 87%.

Claims (2)

The claims 1, DEVICE FOR DEHUMIDING SUSPENSIONS, mainly a fibrous suspension of pulp and paper production, comprising a housing equipped with inlet and outlet nozzles, separated by a filter element in the form of a perforated grate into the lower and upper chambers, and means for washing the grating perforation, characterized in that to increase the productivity of the device, all holes of the perforated grate are equipped with fingers freely installed in them, the length of each of which exceeds the thickness of the grating, by the ends of the fingers are mounted on both sides of the perforated grating of the head, the surface of which on the side of the grating is made flat to overlap the corresponding perforation hole and has a roughness P2 from 320 to 0.1, while the grating is mounted for rotation around an axis oriented along its planes, and the lower chamber has a nozzle for connection to a vacuum system, 2. The device according to claim 1, characterized in that the fingers are made in the form of perforated tubes, under the heads of which a set of rings forming a slotted filter are freely mounted on both sides of the perforated grating. / %twenty/ & 160 / L 7 / & game 2 fO 7 (ri. 4