Sewage treatment

• 1. Screening - mesh
  2. Sedimentation - solids sink
  3. products are Effluent / sludge
  4. UV radiation , ozone , chlorine gas
  5. Effluent - aerobic digestion . Sludge - anaerobic digestion
  6. back into river or used as fertiliser
• Aerobic digestion - Air is pumped through the effluent to supply the bacteria with oxygen
• • Anaerobic digestion - The sludge is sealed in a container to prevent the entry of air, which ensures anaerobic respiration.