2.3.13Chemical Bonding, Application Of Chemical Reactions and Organic Chemistry
Factors Affecting Extraction Processes
5 min read 7 parts Lesson 37 of 54 1 quiz
Section 1 of 7Is extraction worth it?
Economic viability
- Economic viability The central question is whether the money earned from selling the metal is greater than the money spent producing it.
- If the ore is poor or the process too expensive, the metal is not worth extracting.
Main costs
- Main costs Raw materials such as the ore and any other chemicals the process needs.
- Energy, for example heating a furnace or running an electrolysis cell.
- Labour costs, meaning wages for the workforce.
- The site itself, including land, building and equipment.
Section 2 of 7Choosing a site
Location of an extraction plant
Transport links
- Transport links Roads and railways are needed to bring materials in and to take the product out.
Near the coast
- Near the coast A port allows bulky raw materials to be imported cheaply.
- The main reason is importing, not exporting.
Workforce
- Workforce The plant should be near enough to a town to recruit workers, but far enough away that noise and pollution do not affect residents.
Energy supply
- Energy supply Plants that use large amounts of electricity should be close to a power station so that less energy is lost in transmission.
Section 3 of 7Sustainability
Meaning
- Meaning A sustainable process meets today's needs without stopping future generations from meeting theirs.
How metal extraction can be made more sustainable
- How metal extraction can be made more sustainable Reduce the damage done to the environment, including mining and waste.
- Use energy-efficient methods and renewable energy sources.
- Produce as little waste as possible.
- Recycle materials and lower the carbon footprint of the process.
Section 4 of 7Case studies
| Metal | Key factor | Explanation |
|---|---|---|
| Aluminium | Very high energy demand | Electricity is needed for electrolysis and to keep the electrolyte molten, so plants are sited near a power supply or the process becomes uneconomic and unsustainable. |
| Iron | Imported raw materials | Iron ore and limestone for the blast furnace are brought in from elsewhere because of cost and the environmental harm done by quarrying. |
Section 5 of 7Why recycling matters
1Less mining
- Less mining Fewer ores need to be dug up, so there is less damage to habitats and ecosystems.
2Less energy
- Less energy Melting and re-moulding scrap uses much less energy than extracting from ore.
- Recycled aluminium needs only about 5% of the energy of making it from bauxite.
3Less waste
- Less waste Less rubbish goes to landfill, which saves space and the energy used to transport it.
4Jobs and income
- Jobs and income Recycling is a growing industry that provides employment and feeds back into the economy.
Section 6 of 7Key terms
| Term | Meaning |
|---|---|
| Economically viable | Producing enough income to cover the costs of the process and make a profit. |
| Sustainability | Using resources in a way that meets present needs without harming the ability of future generations to meet theirs. |
| Raw materials | The starting substances, such as ores and limestone, used in an industrial process. |
| Recycling | Collecting and reprocessing used materials so they can be made into new products. |
| Carbon footprint | The total amount of carbon dioxide and other greenhouse gases released by a process or activity. |
Section 7 of 7Exam technique
1
Saying plants are built near the coast mainly to export products: the main reason is to import raw materials.
2
Forgetting to mention energyfor metals such as aluminium, electricity cost is the biggest factor in choosing a site.
3
Placing a plant right next to a town: noise and pollution mean it should be near, but not too near.
4
Saying recycling uses no energyit uses much less, not none.
5
Defining sustainability only as 'good for the environment' and ignoring future generations.