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IV. Wastewater Treatment Technologies

Topic IV. 7. Mechanical Wastewater Treatment Facilities - Bar Racks, Grit Chambers, Settling

Tanks: Kinds, Structures, Basic Parameters

Bar Racks

Kinds:

Coarse (b = 30 - 120 mm) Fine (b = 16 - 25 mm)

Vertical Declined

Hand-cleaned Mechanically-cleaned

Fixed Removable Rotating

Disk Drum Wing

Comminutors

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Bar Racks: Kinds

3

Bar Racks: Structures

Declined Mechanically-cleaned Bar Rack

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Bar Racks: Structures

Bar Rack Accommodation

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Bar Racks: Basic Parameters

a) design scheme б) bars cross sections

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Grit Chambers: Kinds

Horizontal Classical Circular Aerated

Vertical Tangential

Single Combined with grease

separating chamber

Mechanically-cleaned Hydraulically-cleaned

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Grit Chambers: Structures

Classical Horizontal Grit Chamber

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Grit Chambers: Structures

Horizontal Circular Grit Chamber

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Grit Chambers: Structures

Horizontal Aerated Grit Chamber

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Grit Chambers: Basic Parameters

Velocities Diagram for the Horizontal Aerated Grit Chamber

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Settling Tanks: Kinds

I. According to their technological functions

Primary settling tanks Secondary clarifiers

II. According to their construction

Horizontal Radial Vertical Combined with other technological units

Imhoff tanks Aerated tanks/secondary clarifiers

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Settling Tanks: Structures

Horizontal Settling Tank

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Settling Tanks: Structures

Details of Horizontal Settling Tanks Inlets and Outlets

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Settling Tanks: Structures

Radial Settling Tank

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Settling Tanks: Structures

Vertical Settling Tank

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Settling Tanks: Structures

Imhoff Tank

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Settling Tanks: Basic Parameters

Settling Kinetics