topic c10- using resources

• resources

  • natural
  • finite
• natural resources

  • renewable resources reform at a similar rate, or faster than the rate we use them
  • this includes wood, water or food
• finite resources

  • non-renewable resources aren't formed quickly enough to be considered replaceable
  • this includes fossil fuels and nuclear fuels
• balancing the risks of resources

  • when extracting resources, typically finite resources, people have to manage to social, economic and environmental impacts
  • for example, mining metal ores is good because it produces useful products and money into the local area, but it is very bad for the environment, ruining habitats and scarring the land
• sustainability- extracting copper

  • bioleaching
  • phytomining
• bioleaching

  • use bacteria to convert copper in the ore into soluble copper
  • this can be extracted by electrolysis or displacement (involving the reactivity series)
• phytomining

  • growing plants in soil that contains copper
  • the plants can't use the copper so the copper gradually builds up in the leaves of the plant
  • the plants are harvested, dried and burnt to extract the copper from them
• helping the environment and maintaining sustainability

  • reduce
  • reuse
  • recycle
• recycling

  • recycling is mainly used as it is much cheaper, better for the environment and quicker than extracting fresh resources from the earth, such as metals
  • recycling of metals usually involves melting the metal down and recasting it
  • glass can also be recycled, bottles are often recycled without changing the shape, but otherwise they are recycled using a similar process to metal
• life cycle assessment (LCA)

  used to assess the environmental impact a product has over its lifetime
• steps of an LCA

  1. getting raw materials
  2. manufacturing and packaging
  3. using the product
  4. product disposal

  • try thinking about this for a product you use a lot- such as a phone- paper bag vs plastic bag
• 1 - getting raw materials

  • does it involve a lengthy, high energy extraction process
  • will it cause excessive damage to the environment
• 2 - manufacturing and packaging

  • will it cause pollution to create the packaging and/ or the product
• 3 - using the product

  • will using this product release harmful gases into the air
  • how long is the product intended to last
• 4 - product disposal

  • what happens when this product is disposed of
  • does it get recycled or entered into a landfill site
• potable water- rainwater

  • water that's been treated or is naturally safe to consume for humans
  • rainwater is fresh water, it doesn't have much dissolved in it
  • despite being mostly clean, it still goes through a process before it is fully safe to drink
• potable water- rainwater

  process- to make sure it is safe to drink

  
• potable water- rainwater- process- to make sure it is safe to drink

  • filtration- a wire mesh screens out larger debris such as twigs
  • filtration- sand and gravel filter any smaller solids
  • sterilisation- water is sterilised to kill bacteria
• potable water- waste water

  • waste water requires a more thorough process before it is potable
• the process to make waste water- potable water

  
• waste water treatment- step 1- screening

  the water is screened for any larger objects such as twigs or bits of rubbish such as plastic bags
• waste water treatment- step 2- sedimentation

  it then stands in a large tank and the solids sink down to the bottom, separating from the liquid at the top
• waste water treatment- step 3- aerobic digestion

  effluent (liquid) is removed and undergoes aerobic digestion using bacteria to break down any organic matter
• waste water treatment- step 4- anaerobic digestion

  sludge (solids) is broken down by bacteria in anaerobic digestion
• waste water treatment- step 5- gas and digested waste produced

  the anaerobic digestion results in methane, used as energy and remaining waste used as fertilisers