Reduce, reuse and recycle to conserve limited resources
Definition
Raw material
A natural material used to make a product, such as crude oil for plastic or wood for paper.
Definition
Environmental impact
A change to the environment caused by a product, process or activity, such as resource depletion, pollution or waste production.
- Metals, glass, building materials, ceramics and most plastics are made from limited raw materials.
- Getting those raw materials from the Earth by quarrying and mining has a large environmental impact.
- Conserving resources means using less of them and getting more out of the ones already extracted.
- The three main approaches are to reduce, reuse and recycle.
Key Idea
- Reducing, reusing and recycling all cut the use of limited raw materials.
- They also lower the energy used, the waste made and the damage to the environment.
Reducing use comes first
Definition
Mining
The extraction of useful minerals or ores from the Earth.
- Reducing how much of a material you use means less quarrying and mining of raw materials.
- It also lowers the energy needed to extract and process those materials.
- Using less packaging or making thinner, lighter products are simple ways to reduce use.
Note
- Reducing use tackles the problem at the start, before any material is even extracted.
- Less extraction means less energy, less waste and less landscape damage.
Reusing: the same product used again
- Some products can be reused without being reprocessed.
- Glass bottles can be collected, washed and refilled many times.
- Glass that is not reused can be crushed and melted to make different glass products.
- Reusing usually saves more energy than recycling, because the product does not need to be broken down and remade.
Example
- A returnable glass milk bottle can be washed and refilled dozens of times before it is finally recycled.
- A crushed bottle, by contrast, must be melted down before it can become new glass.
Recycling: reprocessing materials into new products
- Products that cannot be reused are often recycled for a different use.
- Metals are recycled by melting them and recasting or reforming them into new products.
- How much the material must be separated first depends on the metal and the properties needed in the final product.
- Some scrap steel can be added to the iron from a blast furnace, which reduces how much iron must be extracted from iron ore.
Exam technique
- To evaluate a way of reducing resource use, weigh the energy and raw materials it saves against the energy needed to collect, sort and transport the material.
- Use the data you are given, and remember that reusing usually saves more energy than recycling.
Weighing up reduce, reuse and recycle
- Recycling saves energy compared with extracting a metal from its ore, and it conserves the ore itself.
- Recycling still uses energy to collect, sort, transport and reprocess the material.
- Reusing a product usually uses the least energy of all, because it skips reprocessing.
- The best choice depends on the material, the energy involved and the data you are given.
Self review
- Why does obtaining raw materials from the Earth have a large environmental impact?
- Give one way of reducing the use of a resource.
- How can a glass bottle be reused, and how can it be recycled?
- How are metals recycled?
- Why can adding scrap steel to a blast furnace reduce the use of resources?
