SU1231008A1 - Method of processing waste water - Google Patents

Description

The invention relates to methods for treating wastewater, including the purification of the latter and the treatment of sludges generated during purification.

The purpose of the invention is to simplify the process and increase its reliability by reducing the number of operations with a similar degree of processing, as well as reducing capital costs.

The drawing shows schematically the structures and communications with which the proposed method is realized.

The facilities include a primary settling tank 1, an aero tank 2 with a regenerator 3, a secondary settling tank D, a centrifuge 5 and a drying apparatus 6.

The diagram shows the following pipelines: 7 - for supplying wastewater to the primary clarifier 1; 8 - for the supply of disposed sewage into aeration tank 2; 9 - For feeding the sludge mixture from the aero tank 2 to the secondary settling tank 4; 10 - for disposal of treated wastewater; 11 — for feeding circulating and excess sludge from the secondary settling tank 4 to the regenerator 3; 12 for feeding the centrifuge 5 to the regenerator 3; 13 for diverting aerated mixture of circulating sludge, excess sludge and centrifuge from the regenerator 3; 14 is for supplying this mixture to the wastewater before the primary clarifier; 15 to supply this mixture to clarified wastewater, in front of the aeration tank 2; 16- for feeding sediment from primary. Settler 1 to centrifuge 5,

Conveyor 17 is designed to supply dewatered sludge to the essential apparatus 6, conveyor 18 to supply thermally dried sludge to storage.

The method is carried out as follows.

Wastewater enters through the pipeline 7 into the primary clarifier 1, where it is subjected to mechanical purification .. In the clarified water discharged through the pipeline 8 into the aeration tank 2, a portion of the aerated mixture is fed through pipeline 15 from the regenerator. From the aerotank 2, the sludge mixture is directed to the secondary settling tank 4 via pipeline 9. Purified wastewater is discharged through pipeline 10, and circulating wastewater and excess sludge through pipelines.

the wire 11 enters the regenerator 3, where simultaneously the pipeline 12 is fed with a centrifuge 5, to which sediment from the primary settler 1 enters the pipeline 16. Another part of the aerated mixture is Q, which is determined from the ratio

, 41 1-

where L - MIC dd, “wastewater; 0.41 and 0.65 - empirical coefficients, ... feed through pipeline 14 eastern waters in front of the primary sedimentation tank 1, i

Sediment, dehydrated in a centrifuge. 5, by means of the conveyor 17, is fed to the drying apparatus 6, from where the dried precipitate is conveyed to the conveyor 18 for storage.

Example; Under laboratory conditions, the method is reproducible on real wastewater supplied to two independent blocks of aero-tanks of the sewage treatment plant complex of the city of Kharkov.

The results obtained are presented in the table.

Concentration of contaminants, 35 mg / l:

in source wastewater:

MIC

iodine

197-248

suspended solids

in sewage treatment

waters:

MIC

192-253

12.8-14.6

suspended solids

Sludge concentration in the tank, g / l

10.2-11.7

Aero3, 1-3,8

The duration of the aeration of a mixture of fugate, circulating sludge and excess sludge in the regeneration.

31231008

Table continuation

Sales table

-....-- Load, g MIC 1 silt per day

The duration of settling of wastewater in the primary clarifier, h

Part of a mixture of fugate, circulating and excess sludge, aerated in the regenerator,%, supplied:

into sewage water

ed by primary sedimentation tanks: calculated

actual in the aeration tank: calculated Actual Amount of dry matter of sludge withdrawn from the primary settling tank per centrifuge, g / l wastewater

5 The amount of dry matter of dehydrated sludge, g / l wastewater 0,15-0,21

Amount of dry substance in fugate, g / l wastewater 0.46-0.65

As follows from the table, when implementing the method, the normative quality of treated wastewater is ensured, and the number of operations is reduced from 10 according to the well-known Technical Solution to 5 due to the elimination of the fugate aeration mixed with excess sludge in a separate tank, compaction of the mixture by settling, drying. of this mixture, dehydrated by centrifugation, and drying the centrate in sludge beds. As a result, a significant simplification of the wastewater treatment process is achieved and its reliability is increased.

VNIIPI Order 2518/27

Random polygons pr-tie, Uzhgorod, st. Project, 4

Circulation 864

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Claims (3)

I. WASTE WATER TREATMENT METHOD, including mechanical treatment in primary sumps, biological treatment in aeration tanks with regenerators, centrifugal dewatering of sludge from primary sumps, thermal drying of dehydrated sludge, aeration of the centrate in a mixture with excess sludge, supply of aerated mixture to sewage before and in clarified wastewater in front of aeration tanks, which is due to the fact that, in order to simplify the process and increase its reliability by reducing the number of operations during anal -tech degree of processing, and reduce capital costs, aeration of supernatant in a mixture with the excess sludge is performed in a regenerator for 4,56,0 hours, after which the waste water is fed to the primary settler _ 11 aerated mixture in an amount of Q, defined by the relation Q = 0.41 L ^a6i ~, where L - BOD _{I of the} initial wastewater; 0.41 and 0.65 are empirical coefficients, the remaining amount of the mixture is fed into clarified wastewater before aerotanks, and biological treatment is carried out at a load of 0.15-0.2 g of MIC for 1 g of sludge per day. 2. The method according to π. 1, characterized in that aeration in aeration tanks is carried out at a concentration of activated sludge 3-4 g / L. 3. The method according to π. 1, characterized in that the wastewater in the primary settling tanks settle for 2-2.5 hours Γν 8001621 'ns I 231008