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ECW542

Wastewater Engineering Lecturer:

Tower 1/ Aras

, Room

Ext. Sewage Treatment DA/RH


Learning Outcome At the end of Week 5 students should be able to - describe preliminary treatment - apply knowledge related to preliminary treatment


PRELIMINARY TREATMENT

Screening, Pumping Station, Grit and Grease Removal


SCREENING

Remove larger particles, which can

interfere with subsequent equipment or processes.

Screening devices can be broadly classified as coarse or fine.

Smaller sized openings generate more screenings and more contaminants on screenings.


SCREENING

Need to handle, store, dispose of screenings. Often have screenings of decreasing openings.

Need to work at low and high flows.


SCREENING DESIGN

Bar spacing, materials of construction and dimensions.

Channel depth, width and approach velocity. Headloss through the screens (hL = 1(V2-v2/2g) C Discharge height to accommodate screenings conveying equipment.


SCREENING DESIGN

Angle of screen. Materials of construction and coatings for overall unit.

Screen cover to block wind and improve aesthetics and reduce odor.

Drive unit service factor.


SCREENING DESIGN

Drive motor size and enclosure (for example; totally enclose fan cooled)

Spare parts. Provision of redundant screen or bypass screen.


THANK YOU

ECW542-wk05-L13  

ECW542 Sewage Treatment Lecturer: DA/RH At the end of Week 5 students should be able to - describe preliminary treatment - apply knowledge r...

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