Waste Water Treatment Flashcards
All 6 cards in this deck
What are the stages of sewage treatment?
e.g. sewage from homes- Screening and grit removal
- Sedimentation, producing solid sewage sludge and liquid effluent
- Anaerobic digestion of the sludge and aerobic biological treatment of the effluent
What two substances are produced by sedimentation in sewage treatment?
Solid sewage sludge (which settles) and liquid effluent (above it).
How is sewage sludge treated, and how is liquid effluent treated?
Sludge: anaerobic digestion. Effluent: aerobic biological treatment.
What must be removed from sewage and agricultural waste water, and what extra substances may industrial waste water contain?
Organic matter and harmful microbes; industrial waste water may also contain harmful chemicals.
Put ground water, waste water and salty water in order of how easy it is to obtain potable water from them.
Ground water is easiest, then waste water, and salty (sea) water is hardest.
True or false? Producing potable water from sea water uses less energy than treating waste water.
False. Desalination of sea water requires large amounts of energy, more than treating waste water.