Sciences de la vie et de la Terre

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Interfaces fragiles de la planète terre

Gestion des eaux usées

Managing sewage

Sewage consists of faeces and urine, industrial and
household wastes, water and debris draining from roads.

Biotechnology, engineering, computer control and microorganisms deal with the wastes
collected in sewers.

Try to make a sketch or a text of the managing sewage
with the following words to explain the managing sewage in Valenton plant :

– sewers
– pumphouse and screen (closely spaced metal bars which remove rags, paper, wood etc)
– grit removal
– primary settling tank (and crude sludge)
– aerobic processing (microorganisms : bacteria, fungi, protists)
with activated sludge process, diffusers bubble air
with trickling filter process
– outfall (to the river)

and
– anaerobic processing for sludge
– power house (with methane)
– dumping (of digested sludge)

vocabulary :

– sewer : égout
– grit : sables
– sludge : boues
– to trickle : couler goutte à goutte
– to scrub : racler
– settling tank : bassin de clarification
– processing : processus
– aerobic : aérobie (= en présence d’oxygène)
– power house : centrale électrique

Assessment

The four
following pictures come from Valenton plant.

– Picture A

– Picture B

– Picture C

– Picture D

1. Give a title to each of them
2. Put them in the right order
3. Choose one picture, sketch it, label it and describe this particular treatment stage.