Life Cycle Assessment

• A life cycle assessment is used to assess the environmental impact a product has over its whole lifetime
• 4 stages of an LCA (Use the abbreviation EMUD to remember)

  • Extracting and processing the raw materials  
  • Manufacturing and packaging the raw materials  
  • Using your product  
  • Disposing of your product 
• An LCA provides a way comparing several alternative products to see which one causes the least damage to the environment
• To carry out an LCA, scientists measure the impact of:

  • Extracting the raw materials  
  • Processing the raw materials  
  • Manufacturing the product  
  • How the product is used  
  • How the product is transported 
  • How the product is disposed of at the end of its life 

   
• Many modern products contain plastics and metals (Such as copper)
• Plastics are polymers
• Polymers (e.g. plastics) are produced using crude oil
• Negatives of extracting metals and raw materials?

  • Extracting a metal from its ore can produce large amounts of toxic waste products  
  • Damage the local environment   
  • Requires a lot of energy   
  • Burns fossil fuels to produce energy, which can lead to climate change 
• Examples of how extracting raw materials damages the environment

  • Cutting down forests for their wood can damage the local environment  
  • Digging huge mines to extract ores can damage the local environment 
• Examples of how processing raw materials indirectly damages the environment

  • Huge amounts of energy are required for the fractional distillation of crude oil  
  • Huge amounts of energy are required for extracting metals from their ores  
  • Lots of pollutants can be released when cleaning extracted ores 
• Explain how polymers (such as plastics) are produced using crude oil?

  1. First the oil must be extracted from the ground and then transported to oil refineries  
  2. The hydrocarbons must be separated and then cracked  
  3. Finally, the polymer must be produced  
  4. (Extra Info – All these processes require a large amount of energy, which is generated by burning fossil fuels) 

  
• Extracting metals takes a huge amount of energy. Explain how metals are extracted?

  1. First the ore has to be dug out of the mine and transported for processing  
  2. The metal then has to be extracted from the ore  
  3. This can produce large amounts of toxic waste products 

  
• Assess the environmental impact of this toy?

  1. The toy could involve a large number of batteries  
  2. Producing batteries releases a large amount of toxic waste 

  
• Many modern products contain a number of harmful chemicals - These chemicals have to be disposed of carefully , and this might require a large amount of energy
• It takes energy to transport used products for disposal e.g. to a landfill or recycling centre
• Plastic bags are produced using chemicals from crude oil
• Paper bags are produced using wood from trees
• Crude Oil is a non renewable resource
• Trees are a renewable resource - We can plant more trees
• Extracting crude oil can be harmful to habitats e.g. if there is an oil leak
• Felling trees for wood is extremely destructive to habitats like forests
• Both crude oil and wood need to be chemically processed - In both cases, this requires a lot of energy and releases waste products
• Making paper requires huge amounts of water
• Plastic shopping bags are strong - they are often reused e.g. as bin liners
• Paper shopping bags are not strong , and often tear - they are often used only once before being thrown away
• At the end of their lives, both plastic bags and paper bags have to be transported either for recycling or to landfills
• Paper bags are often heavier than plastic bags - they take more energy to transport
• Plastic is non-biodegradable - It is not broken down by microorganisms
• Paper breaks down quickly , especially when wet
• Because they are non-biodegradable, plastic bags remain in the environment for a very long time - So plastic bags are a major form of litter , and fill up landfills
• We can measure the use of water and energy . We can also measure the production of some waste products
• We cannot always be certain of how damaging the use of water and energy , and the production of waste products are to the environment