Life cycle assessment and recycling

• Life cycle assessment


  Assessing the environmental impact of products in each stage: extracting and processing raw materials, manufacturing and packaging, use and operation during its lifetime, disposal at the end of its useful life, including transport and distribution at each stage
• Use of water, resources, energy sources and production of some wastes can be fairly easily quantified in life cycle assessment
• Allocating numerical values to pollutant effects is less straightforward and requires value judgements, so life cycle assessment is not a purely objective process
• Selective or abbreviated life cycle assessments can be devised to evaluate a product but these can be misused e.g. in support of claims for advertising purposes
• Ways of reducing the use of resources

  • Reduction in use, reuse and recycling of materials by end users reduces the use of limited resources, use of energy sources, waste and environmental impacts
• Materials produced from limited raw materials

  • Metals
  • Glass
  • Building materials
  • Clay ceramics
  • Most plastics
• Much of the energy for the processes of producing materials from limited raw materials comes from limited resources
• Obtaining raw materials from the Earth by quarrying and mining causes environmental impacts
• Reuse


  Some products, such as glass bottles, can be reused by crushing and melting to make different glass products
• Recycling


  Other products cannot be reused and so are recycled for a different use
• Recycling metals


  1. Melting and recasting or reforming into different products

  2. Amount of separation required depends on the material and the properties required of the final product
• Some scrap steel can be added to iron from a blast furnace to reduce the amount of iron that needs to be extracted from iron ore