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.