SU1611888A1 - Method of deep purification of waste water - Google Patents

Abstract

The invention relates to the treatment of wastewater, can be used in the treatment of domestic and close to them in composition of wastewater and allows you to increase the efficiency of the treatment process. After mechanical cleaning, wastewater is sent to the aeration tank and then to secondary sedimentation tanks and biological ponds. Return activated sludge is pumped through line a sludge aeration duct, to the same fed excess activated sludge in an amount emom determined by the formula: Q = Q _{communication ua} (K A _to ^-0,015.) / A _n ^-K. A 0.015 _in where Q _ia - amount of excess activated sludge, m ³ / day

Q _sv - wastewater flow, m ³ / day

A _in - permissible concentration of suspended substances in the water leaving the bioponds, g / l

A _c - concentration of sludge output from the secondary clarifiers, g / l

K = 8-12. The method allows to reduce the duration of the stay of wastewater in bioponds by 2-5 times and reduce capital and operating costs by 3-4 times. 1 tab.

Description

The invention relates to the treatment of water and can be used in the treatment of household and close to them on the composition of industrial waste

waters ..

The purpose of the invention is to increase the cleaning efficiency by increasing the productivity of biological ponds.

For carrying out the process, the wastewater after mechanical cleaning is directed to aeration tanks and then to secondary sedimentation tanks. Purified water is fed into biological ponds. Returnable activated sludge is pumped through the pipeline into the sludge channel of aeration tanks, and excess activated sludge is directed there in the amount determined by the formula:

CHS.V (K-av-0.015) q u.q - kT-GGOTOTS gpe q - the amount of excess .Ci 3 /.

tive sludge, m / d, is the wastewater flow rate, and a is the permissible concentration of suspended matter in the water coming out of the bioponds. de, g / l;

a - sludge concentration, out- MOGO from secondary settling tanks, g / l; K - 8-12.

sc

00

oo

The physical meaning of the coefficient K is the ratio of the concentrations of suspended substances in the water before and after settling, depending on the duration of the sludge in aerated and settling sections. During tertiary treatment of urban and close to them composition of biologically treated wastewater, its value ranges from 8-12. Additional supply of excess activated sludge to aerotanks in a certain amount leads to an increase in the oxidative capacity of these facilities, increases the removal of sludge from secondary settlers, which, in turn, leads to a corresponding increase in biomass in biological ponds and a reduction in the duration of water treatment.

Example. 30 thousand of waste water I are fed to the treatment plants with the following indicators, Igm / l: MIC ddts 220; concentration

250. After mechanical cleaning, the concentration of suspended substances is reduced to 125 mg / l. I The increase in sludge in aeration tanks is: Pr 166 mg / l. The total amount of excess sludge at its humidity I = 99.2% is du., 622.5. ; The amount of excess activated sludge directed to the aeration tank sludge channel is determined by the proposed formula:

; qj.g 30000 m / day; K 10; a e 0.01 g / l; ac 8 g / l; H & S, 323.4 m VcyT, which is 48% of its total

lichkoy.

The water purified in bioponds has the following indicators, mg / l:

- 3; concentration of suspended substances 10.

The table presents the comparative data on the effectiveness of urban wastewater treatment on the proposed and known methods. The use of the proposed method makes it possible to reduce the duration of the stay of the treated wastewater in biological ponds by 2-5 times and 3-4 times lower capital and operating costs.

Invention Formula

A method of deep sewage treatment, including mechanical treatment in primary sedimentation tanks, biological treatment, in aeration tanks and secondary sedimentation tanks, recycling of activated sludge to aerotanks, removal of excess activated sludge from the system and subsequent purification in biological ponds, which means In order to increase the cleaning efficiency by increasing the productivity of biological ponds, excess activated sludge is additionally supplied to aerotanks in an amount determined by the formula in

(K.a - 0.015)

TS.SZ

, 015

five

0

where q

u.a

Chs-b in

ih

the amount of excess activated sludge.; wastewater flow, m / d; permissible concentration of suspended solids in water leaving bioponds, g / l; concentration of activated sludge removed from secondary clarifiers, g / l.

Claims (1)

Claim A method of deep wastewater treatment, including mechanical treatment in primary sumps, biological treatment, in aeration tanks and secondary sumps, recirculation of activated sludge into aeration tanks, removal of excess activated sludge from the system and subsequent post-treatment in biological ponds, which differs in that, with the aim of increasing cleaning efficiency by increasing the efficiency of biological ponds in aeration tanks are additionally fed excess activated sludge in an amount determined by the formula _{q CB (Ka & - 0,015)} q α · α - Ζ '"Κ ™ + _ 070Ϊ5 'Wherein q _ua - amount of excess activated sludge, m ³ / day .; q _{c 0} - wastewater flow rate, m ³ / day; and _β is the permissible concentration of suspended solids in the water leaving the biological ponds, g / l; a ^ is the concentration of activated sludge removed from the secondary settling tanks, g / l. Processing method Coefficient K The working dose of sludge in the ponds, g / l The total duration of the post-treatment, h The total volume of ponds, m ^} Amount of excess sludge sent to aeration tanks [reduction in the volume of ponds compared to the known,% 3 / m / sut % of the volume Famous - 0.015 193 241250 0 0 - Suggested 10 0.1 38 47500 323.4 48 ’ 83