Using Resources

• what do humans use earth's resources for

  warmth, shelter, food and transport
• what do natural sources provide

  supplemented by agriculture they provide food, timber, clothes and fuels
• where do we get finite resouces from

  earth, oceans and atmosphere to provide energy and materials
• what is sustainable development

  meets the needs of current generations wihtout comprimising the ability of future generations to meet their own needs
• what is potable water

  water that is safe to drink
• Is potable water pure

  no
• what do you need low levels of in drinking water

  dissolved salts and microbes
• what dictates method used to obain potable water

  supplies of water and local conditions
• how is most potable water produced in the UK

  • choose appropriate source
  • pass water through filter beds
  • sterilise
• where is most of the potable water ontrained from in the UK

  rain water provides water with low levels of dissolved substances (fresh water) which collects in the ground and in lakes and rivers
• what are the three ways to sterilise water

  chlorine, ozone and ultraviolet light
• what is another method to obtain potable water if fresh water is limited

  desalination of salty water or sea water
• what process is used in desalination

  distillation or using membranes by reverse osmosis
• what are the issues with desalination and reverse osmosis

  require large amounts of energy
• what produces large amounts of waste water

  urban lifestyles and industrial processes
• what is removed from sewage and agricultural waste

  organic matter and harmful microbes
• what is removed from industrial waste

  organic matter and harmful chemicals
• what are the steps in sewage treatment

  • screening and grit removal
  • sedimentation to produce sewage sludge and effluent
  • anaerobic digestion of sewage sludge
  • aerobic biological treatment of effluent
• 2 ways to extract copper from low grade ores

  phytomining and bioleaching
• what do phytoming and bioleaching avoid compared to traditional methods

  digging, moving and disposing of large amounts of rocks
• what does bioleaching use to exract the copper

  bacteria to produce a leachate that contain metal compounds
• how is copper extracted by phytomining

  • plants are used absorb metal compounds
  • The plants are harvested
  • Then burned to produce ash that contains metal compounds
• how can metal compounds be processed to obtain the metal

  example includes using scrap iron to displace the copper from a solution or by electrolysis
• what is a life cycle assessment (LCA)

  a way to assess the environmental impact of a product at all stages
• what are the stages assessed in a LCA

  
  

  • extracting and processing raw materials
  • manufacturing and packaging
  • use and operation during its lifetime
  • disposal and end of its useful life, includes transport and distribution
• what resouces can be easily quantified

  water, resouces, energy sources and production wastes
• what type of substance is hard to quantify

  pollutants as based on judgement so is not purely objective
• what is the issue with selected or abbreviated LCA's

  misused to reach conclusion, e.g. false advertising claims
• how can we reduce the use of resouces

  resue and recycle
• examples of products from limited resources

  metals, glass, building materials, clay ceramics and most plastics
• where are the resources obtained from for these products

  quarrying and mining whch causes envrionmental issues
• what are the two ways to resue these products

  reuse (glass) or recycled
• how can metals be recycled

  melting and recasting or reforming into different product
• what dictates the amount of recycling needed for a metal

  material and its final use (product)
• how can glass bottles be reused

  crushed then melted to make different glass products.
• what happens to a product that can't be reused

  can be recycled for a different use
• what is happening to earths metal resourcs

  becoming limited and scarce
• how can metal compounds be extracted after bioleaching

  by displacement with scrap iron or electrolysis
• what are the impacts of reuse and recycle

  • reduces use of limited resources
  • energy use
  • reduces waste so environmental impact