RU1787958C - Equipment for anaerobic treatment of sewage - Google Patents

Abstract

Usage: anaerobic treatment of industrial wastewater at the enterprises of the food industry and the processing of agricultural products. SUMMARY OF THE INVENTION: An anaerobic wastewater treatment device comprises a vertical sealed cylindrical body with fermentation and sedimentation chambers separated by coaxial cylindrical baffles with overflow openings in the upper part. In order to increase the cleaning efficiency, coaxial settling chambers with coaxial partitions installed in them with overflow openings in the lower part are provided. 1 ill.

Description

The invention relates to the field of anaerobic wastewater treatment and can be used for the treatment of industrial effluents in the food industry.

A device for wastewater treatment and sludge treatment is known, comprising a biological treatment chamber with disc biofilters, a settling chamber and a secondary settling chamber. All chambers are located coaxially and separated by coaxial partitions forming a labyrinth cocoa, and the sedimentation and collection chamber and the secondary sedimentation chamber are provided with pipelines for supplying sediment to the septic chamber.

The process of wastewater treatment in this device consists in the fact that organic pollution is adsorbed by biofilm on disk biofilters, and all suspended solids (sediment) are gradually deposited in the primary and secondary sedimentation chambers, passing through the labyrinth channel formed by coaxial partitions.

The disadvantages of this design include the fact that the contaminated wastewater, passing through disk biofilters, comes into only surface contact with the biofilm of microflora, which does not provide a large degree of purification of wastewater from pollution. As a result, the treated wastewater contains a large amount of contaminants and leaves the device as silt water and requires further treatment.

In addition, the sediment from the primary and secondary settling chambers is partially disposed of in the septic chamber by fermentation by heating and stirring, and the fermented sediment is removed from the device for further processing or disposal.

Thus, the known device cannot provide sufficient efficiency

with

Xi

00 VJ ON SL 00

Wastewater treatment without additional energy and without further treatment of the effluent sludge.

The purpose of the invention is to increase the efficiency of the treatment of industrial wastewater from organic impurities by providing an optimal hydrodynamic regime and a combination of bulk fermentation and settling processes.

The goal is achieved in that in the device for anaerobic wastewater treatment / containing a vertical sealed cylindrical body with digestion and sedimentation chambers separated by coaxial cylindrical partitions with overflow holes in the upper part, additionally coaxially located sedimentation chambers with installed in the upper part are provided them with coaxial partitions with overflow holes in the lower part.

The diameter of the central digestion chamber is determined by the formula

d -§ - (0.095-0.105) -U-; b and

where D is the diameter of the device, m;

N - the height of the device, m;

H / D 1.2-1.3 is a typical ratio for sedimentation processes.

The diameters of the coaxial partitions with overflow holes in their lower part of the settling chambers are determined by the formula:

d0i: do2: do3 (0.205-0.215) O: (0.535-0, 545) D: (0.855-0.865) D.

And the diameters of coaxial partitions with overflow holes in their upper part of additional digestion chambers are determined by the formula:

dci: dC2: dc3 (0.345-0.355) D: (0.675-0, 685) D: (0.995-1.005) 0.

The drawing shows the proposed device, a longitudinal section.

The device comprises a sealed housing 1 with a central digestion chamber 2, sedimentation chambers 3 formed by coaxial cylindrical partitions 4 with overflow openings 5 in their lower part. Additional digestion chambers 6 are formed by coaxial baffles 7 with overflow holes in their upper part 8. The device includes a pipe 9 for supplying wastewater, a water trap 10 for discharging purified water, and a pipe 11 for removing biogas (methane gas) formed.

The device operates on the principle of perfect displacement as follows.

Wastewater through pipeline 9 enters the lower part of the central chamber

 fermentation 2, where there are methane-forming microorganisms and in the volume of which the main process of destruction of organic inclusions contained in waste water is carried out.

From the central digestion chamber 2, wastewater through the upper overflow opening 8 of the coaxial partition 7 enters the first settling chamber 3 from the center of the housing, passes through it and through

lower overflow hole 5 of the coaxial septum 4 and additional fermentation chamber 6 enters the first from the center of the housing 6. Subsequently, the wastewater in the direction from the center of the housing to

the peripheries pass sequentially through the remaining settling and digestion chambers, which together form a vertical labyrinth channel in which the direction changes

flow alternately from bottom to top and top to bottom, and there is also a change in the magnitude of the velocity of the main wastewater stream.

In sedimentation chambers, the process of deposition (delay) of undestructed organic particles is carried out, and in

additional digestion chambers pro. comes an additional deeper

fermentation of fine organic particles.

The presence of several settling chambers allows the sequential deposition process to be carried out depending on the size of the deposited particles and their complete destruction with the help of methane-forming microorganisms in the entire volume of the stream of treated wastewater.

Purified water is discharged from the device body through a water trap 10. Formed during the destruction of organic

Inclusions, methane gas (biogas) is collected in the upper part of the device and removed from it through the pipe 11.

EXAMPLE of calculating an anaerobic wastewater treatment device.

The calculation is carried out on the volume allowing anaerobic treatment of 1QO m3 / day of wastewater with organic inclusions (solids content up to 2.5%), according to the average values of the established ratios, namely:

d -P - 0.1

ABOUT

and

D

H 1.250;

doi: do2: d03 0.21 0: 0.540: 0.860; dci: dc2: dc3 0.350: 0.68: 0.

Estimated Data: D is the diameter of the cylindrical body, m 4.70 N is the height of the cylindrical body, m 5.80 d is the diameter of the central (main) digestion chamber, m 0.66 doi is the diameter of the coaxial partition with an overflow hole in its lower part settling m 0.99 2.54 4.04 del - diameter of the coaxial septum with an overflow hole in its upper part of the additional digestion chamber, m 1.16 3.20 dc3. 4.70 The diameter of the central digestion chamber d D / 6- (0,095-0,105) H / D is experimentally determined in such a way that there is an optimal ratio of wastewater flow rates at the outlet of the supply pipe and in the volume of the central digestion chamber itself, which provides the necessary mixing the flow, but does not entail the entrainment of large suspended organic impurities from the central digestion chamber. With a smaller diameter of the central digestion chamber, a sufficiently high flow rate will be maintained and at the same time the ablation rate and large suspended particles will exceed their sedimentation rate, which will reduce the degree of wastewater treatment. With a larger diameter of the central digestion chamber, the decrease in flow rate will be so significant that there will be no necessary mixing and contact of microflora in the entire volume of wastewater, which will also lead to a decrease in the degree of purification of wastewater.

The presence of coaxial cylindrical partitions with overflow holes in their upper part changes the direction of flow of the purified water both in the central digestion chamber and in additional digestion chambers, which ensures, on the one hand, the greatest degree of completeness of conversion of organic inclusions, and on the other hand, creates a condition for the deposition and retention of suspended particles in the main digestion chamber for their cleavage by anaerobic microflora.

The diameters of the coaxial partitions with overflow holes in the upper part of the additional digestion chambers are related to the case diameter of the proposed device, namely: dci: dc2: dc3 (0.345-0.355) D: (0.67.5-0, 685) D : (0.955-1.005) D. This ratio is determined experimentally as optimal, which allows achieving such a change in the flow rate of the water being purified that provides gradual deposition of suspended particles in the settling chambers with gradually decreasing dimensions in the direction from the center of the device to its periphery. In the additional digestion chambers, complete destruction of these particles by means of microflora into biogas is achieved.

The equipment of the proposed device with additional coaxial partitions with overflow holes in their lower part provides a change in the flow rate of the treated water both in magnitude and direction, which creates

5 are the best conditions for the delay in the sedimentation chamber of suspended particles, which leads to the treatment of wastewater from organic inclusions by anaerobic microorganisms in biogas (methane gas).

0 The diameters of the partitions with overflow holes in their lower part are related to the diameter of the housing of the proposed device, namely: doi: d02: d03 (0.205-0.215) D: (0.535-0.545) D: (0.8555 -0.865) 0 .

If the diameters of these partitions increase or decrease, the distances between the partitions with upper and lower overflow openings will change, which will lead to a change in the optimal flow rates of wastewater. An increase in the flow rate will lead to the entrainment of organic impurities and microflora, and a decrease in the flow rate will result in to

5 compaction of the settled particles and to reduce the surface of their contact with microflora. Thus, an increase or decrease in the flow rate of purified water leads to a decrease in the degree of purification

0 due to entrainment of suspended particles or due to a decrease in the degree of conversion of organic inclusions to biogas.

All the above ratios are established experimentally as

5 are optimal and can vary in insignificant ranges, namely:

doi: d02: do3 (0.205-0.215) D: (0.535-0, 545) D: (0.855-0.865) D;

dci: dc2: dc3 (0.345-0.355) D: (0.675-0; 685) D: (0.995-1.005) 0.

It should be noted that the use in the proposed device operating on the principle of perfect displacement of alternating cylindrical partitions with upper and lower overflow openings creates a labyrinth path with a variable flow direction and a variable change in flow velocity, which at the same time provides the greatest completeness of anaerobic digestion and sedimentation days of suspended particles, the delay of which in the digestion chambers also increases the degree of anaerobic conversion of organic inclusions.

The proposed device provides a fairly complete anaerobic treatment of wastewater with organic impurities when using a single-hull installation.

Claims (1)

The claims An anaerobic wastewater treatment device comprising a vertical sealed cylindrical body with fermentation and sedimentation chambers separated by coaxial cylindrical  STOCK | partitions, characterized in that, in order to increase the efficiency of wastewater treatment from organic inclusions by ensuring optimal hydrodynamic regime and a combination of the processes of volumetric fermentation and sedimentation, in the coaxial partitions forming the digestion chambers, overflow openings are made in their upper part, in On the coaxial partitions forming the settling chambers, overflow holes are made in their lower part, the diameter of the central digestion chamber is determined by the ratio 5 d D / 6- (0,095-0,105) H / D, where D and H are the diameter and height of the housing of the device, the diameters of the coaxial partitions of the digestion chambers in the direction from the center to the periphery of the housing are defined 0 by the ratio (0.345-0.355) D: (0.675-0.685) D: (0.995-1.005) 0, and the diameters of the coaxial partitions of the settling chambers in the direction from the center to the periphery of the body are determined by the ratio (0.2055 0.215) D: (0.535-0.545 ) D: (0.855-0.865) D. biogas