Why low-grade copper ores need new methods, how plants and bacteria collect metal compounds, and getting copper out of the solution by displacement or electrolysis, with the masses worked out.
What you will learn
- Explain why low-grade ores need new extraction methods
- Describe phytomining and bioleaching and compare them
- Calculate masses of ore, ash and copper, and the scrap iron needed to displace copper
Why new methods are needed
The world's supply of high-grade copper ore is running out.
What is left is low-grade ore, with only a small percentage of copper, and old mine waste.
- An ore is 0.5% copper. Mass of ore for 10 tonnes of copper = 10 × 100 ÷ 0.5 = 2000 tonnes
- waste rock = 2000 − 10 = 1990 tonnes to dig, move and dump
Traditional mining of ore like this means huge pits, heaps of waste and a lot of energy. Biological methods avoid most of that.
The rest of this lesson and its 9 practice questions are locked.
In this lesson
- Why new methods are needed
- Plants and bacteria
- Getting the copper out
- Try it: Work backwards from the percentage
9 practice questions, marked as you go; about 25 minutes in all.
Key terms
High-grade, Low-grade, Ash, Bacteria, Leachate, Compounds
In this unit: Using resources
Making water potable and the water practical, life cycle assessments and recycling, phytomining and bioleaching, corrosion and materials, and the Haber process with NPK fertilisers, with every calculation worked.