Treating waste water
Aiming for Grade 4 LOs:
• List what is removed from waste water before
it can be released.
• State the main processes in sewage
treatment.
• State uses of sewage slurry.
Aiming for Grade 6 LOs:
• Explain why waste water should be treated
before it is released into the environment.
• Describe the main processes in sewage
treatment.
• Explain uses of sewage slurry.
Aiming for Grade 8 LOs:
• Evaluate the ease of obtaining potable water
from waste, ground, or salt water.
• Explain in detail how and why waste water is
processed before it is released into the
environment.
• Evaluate the uses of sewage slurry.
Waste water requires treatment before being
released into the environment
• Urban lifestyles and Industrial waste water may require removal of
organic matter and harmful chemicals.
Sewage and agricultural waste water
• require removal of organic matter and harmful microbes.
Sewage treatment includes:
• screening and grit removal
• aerobic biological treatment of effluent.
• anaerobic digestion of sewage sludge
• sedimentation to produce sewage sludge and effluent
• Students should be able to comment on the relative ease of obtaining potable
water from waste, ground and salt water.