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II. Sewer Networks and FacilitiesTopic. II. 12. Detention (Retention) Basins: Kinds

and Structures. Sewerage Pumping Stations

Detention Basins: Kinds

I. According to their technological function For first flush detention For hydraulic relief of the sewer network For wet weather regulation of inflow to the WWTP

II. According to their position in respect to the sewer main On the line of the sewer mains Of line the sewer mains

III. According to their structures Open air detention basins Underground (covered) detention basins

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Detention (Retention) Basins: Kinds and Structures

Detention Basin on the Main Line with Gravity Emptying: Longitudinal Section (Scheme)

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Detention (Retention) Basins: Kinds and Structures

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Detention (Retention) Basins: Kinds and Structures

Screw Pumping Station at the Of Line Detention Basin

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Detention (Retention) Basins Volume Determination

I. Graphical Determination I - local hydrograph Hatched area represents the

detention volume Qmax/2 - chosen permanent water

discharge from the detention basin

II. Analytical Determination

V = Kdb.Qmax.to

V - detention basin volume

Kdb - detention basin coefficient

Kdb = 0.01 - 1,5; (Kdb = 0,25 - 0,55)

Qmax - hydrograph peak

to - time to peak

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Sewerage Pumping Stations

Purpose

I. Pumping Stations at the Sewer and Drainage Networks Rising sewer collector elevation Transportation of sewage and runoff to higher elevation Runoff discharge into receiving water

II. Pumping Stations at the Wastewater Treatment Plants Rising wastewater at the WTP inlet Sludge and wastewater transportation according to the technological

requirements Part of the sludge dewatering equipment

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Sewerage Pumping Stations (SPS)

Schemes Illustrating the SPS Purposea - Rising sewer collector elevation; б - Wastewater pumping transportation

1 - inlet sewer pipe; 2 - receiving chamber; 3 - machines hall; 4 - gravity sewer collector;

5 - pressure sewer pipe

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Sewerage Pumping Stations (SPS)

Schemes for SPS Structures with Submerged Pumpsa - pumps with horizontal axes; б - pumps with vertical axes

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Schemes for SPS Structures with Non-submerged Pumps

Sewerage Pumping Stations (SPS)

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Sewerage Pumping Stations (SPS)

Classical SPS with Horizontal Centrifuge Pumps

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Sewerage Pumping Stations (SPS)

1 - inlet sewer channels

2 - belt conveyor

3 - bar racks

4 - sluice gates

5 - overhead crane

6 - bridge crane

7 - electrical motor

8 - pumps

9 - barrel for wasted lubricate

10 - pressure pipes

11 - emptying pipe

12 - drainage pump

13 - pipes for suction of sediments

14 - service (water supply) pumps

15 - barrel

16 - service pipe

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Sewerage Pumping Stations (SPS)

SPS with Screw Pumps