The environment

Definition of sustainibility

development that meets the needs of current generations without compromising the ability of future generations to meet their own needs.

What is life cycle assesment?

an analysis of the overall environmental impact that a product may have throughout its lifetime

What are the 4 stages of Life Cycle Assessment

• 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.

LCA of a plastic bag (full answer )

Raw material: crude oil ; finite source; requires lots of energy to process

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Manufacture: Fractional distillation, cracking and polymerisation. Not much waster as crude oil. Is completely used and cheap to manufacture.

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Usage: is reuseable

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Disposal: can be recycled but is costly and causes pollution. Can be stored in a landfill, takes up space and isn’t biodegradeable.

LCA of a paper bag (full answer.

Raw material: Recycled paper or trees. Making paper requires more energy than recycling paper but much less than making plastics.

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Manufacture: pupling paper uses a lot of energy, sulfur dioxide and produces waste.

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Usage: Most are not reuseable.

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Disposal: Biodegradeable, non-toxic and can be recycled.

is the LCA of a paper bag or a plastic bag better?

* Considering both life-cycle assessments, the plastic bag may be the better option. Even though they aren’t biodegradable, they do have a **much longer lifespan** and thus are less harmful than paper bags
* Much depends on the usage of the item:
* If the paper bag is recycled then it could be more favourable to use it
* If the plastic bag is used only once, then then the argument for using plastic bags is less favourable

How can the number of iron needed to be extracted from iron ores reduced?

Some scrap steel can be added to iron from a blast furnance to reduce the amount of iron that needs to be extracted from its ore.

How can glass bottles be reused?

They can be crushed and melted to make different glass produtcs.

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other products canot be reused so they re reclcked for a different use.

Disadvantages of recycling

* Collection and transport of material to be recycled requires **energy** and **fuel**
* **Workers, vehicles, and work sites need to be organized and maintained**


* Materials need to be sorted **before** they can be recycled which also requires **energy** and labor
* Products made from recycled materials may not always be of the **same quality** as the original

Advantages of recycling

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### **Economic Implications**

* It is **economically beneficial** to recycle metals, especially those that are costly to extract such as aluminium
* Recycling is fast becoming a **major industry** and provides **employment** which feeds back into the economy

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### **Environment**

* Mining and extracting metal from ores has **detrimental** effects on the environment and ecosystems
* It is much more **energy efficient** to recycle metals than it is to extract them as **melting** and **re-moulding** requires less energy
* Recycling decreases the amount of waste produced, hence saving space at **landfill** sites and energy in **transport**

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### **Raw Materials**

* There is a **limited supply** of every material on Earth
* As global populations increase there is a greater need for effective recycling methods to attain **sustainable development**
* Mining and extraction use up valuable **fossil fuels**, which contributes to **climate change**

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