Life Cycle assessment and recycling

Question 1

Lifecycle ASsessment

Answer 1

Aims to put a number on the environmental impact of a product on the environment

Question 2

Plastic Bags

Answer 2

• Polymers have to be extracted from crude oil
• Oil rigs
• Transported to oil refineries
• Hydrocarbons then have to be separated and cracked
• Polymer has to be produced
• Lots of energy required and burning of fossil fuels
• Contributes to climate change

Question 3

Metals

Answer 3

• Ore dug out
• Transported for processing
• Extracted, requiring lots of energy and producing harmful waste products
• Packaging waste
• All stages require lots of energy
• Producing batteries involves handing of lots of toxic waste

Question 4

Dispolsal

Answer 4

Lots of products contain harmful compositions

Being disposed of causes environmental harm

Disposal needs to be done carefully which requires a lot of energy

Takes energy to transport products to a dumping or recycling centre

Question 5

Paper Bags vs Plastic

Answer 5

Paper

• Renewable, wood
• Deforestation is extremely disruptive to habitats
• Both need chemical processing, (lots of energy and waste)
• not as strong, only used once
• Both need to be transported for recycling or in landfills
• Heavier so more energy for transport
• Biodegradable, so less environmentally damaging

Plastic

• Non-renewable
• Extraction of crude oil is environmentally damaging, oil leaks
• Both need Chemical processing (lots of energy and waste)
• Used many times
• Both need to be transported for recycling or in landfills
• Not biodegradable so environmentally damaging, LITTER, Fill up landfills

Question 6

Limitations

Answer 6

Can be inaccurate, information manipulated for advertisement, Biased

Question 7

Reducing use of resources (Glass bottles)

Answer 7

Can be melted, reused and reshaped in recycling

Question 8

Reducing use of resources (Metals)

Answer 8

• Can be recycled by melting and recasting or reforming into different products.
• The amount of separation required for recycling depends on the material and the properties required of the final product
• Some stainless steel can be added to iron from a blast furnace to reduce the amount of iron that needs to be extracted from Iron Ore

Question 9

Corrosion

Answer 9

The destruction of materials by chemical reactions with substances in the environment

Rusting is an example of corrosion, and ONLY HAPPENS TO IRON OR ALLOYS OF IRON (eg. Steel)

Rusting requires both AIR and WATER

Question 10

How can we prevent corrosion?

Answer 10

• Grease
• Paint
• Coating material with metal (electroplating)

Aluminium has an oxide layer where aluminium has reacted with O2 to form a protective layer from further corrosion

Question 11

What is sacrificial protection?

Answer 11

Coating Iron nails with ZINC is called GALVANISING.

The layer of zinc acts as a barrier from air and water. This prevents the iron from corrosion.

Zinc corrodes INSTEAD of the Iron, and by using the more reactive metal like this is called sacrificial protection

Replaced every couple of years