unit 9 and 10 chemistry

?
View mindmap
  • Using Resources and Chemistry of the Atmosphere
    • Waste Water and Sewage
    • Atmospheric pollutants from fuels
    • Polluting the atmosphere
  • 1. Sewage is screened which involves removing large bits of material.
    • 2. Sewage is allowed to stand in sediment tank so that heavy solids sink to the bottom producing sludge.
      • 3. The effluent in tank is removed and treated by biological aerobic digestion.
        • 4. Air is pumped through water to encourage aerobic bacteria to break down the organic matter
          • 5. The sludge from the tank is also removed and transferred into smaller tanks. Here it gets broken down by the anaerobic respiration.
            • 6. Anaerobic digestion releases methane gas which is used as an energy source and the remaining waste is used as fertiliser.
              • 7. For waste water containing toxic substance, additional stages of treatment may be used to add extra chemicalss.
  • Pollution can occur: in water, from sewage, fertlisers or toxic chemicals.
  • Incomplete combustion = not enough oxygen, meaning instead of carbon dioxide you get carbon monoxide or soot which is bad for environment.
  • problems with INCOMPLETE combustion = carbon monoxide is poisonous to humans. It is also colourless and odourless so it is difficult to detect.

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all The earth and its atmosphere resources »