With a growing population and rising energy and resource consumption, there is an increasing need to locate and retrieve valuable materials from within the earth. Copper remains a valuable resource and a recent supply deficit has driven copper prices to triple in the last 10 years.
Copper has become so sought after in modern technology and engineering industries, there are even plans to demolish an entire mountain in Peru simply to provide copper ore for China’s growing economy. However, if you plunge 4000m into the Pacific Ocean, there are vast, untapped resources of copper, manganese, cobalt and other valuable rare earth minerals on the seabed. Underwater deposits can have up to 10 times more copper ore than material that is mined on land. With rising mineral costs it is becoming economically viable to start the search under the ocean surface.
The richest mineral deposits are found lining the margins of tectonic plates, around fields of miniature volcanoes called hydrothermal vents. These vents spew superheated water and plumes of noxious chemicals, so the working conditions are very difficult and dangerous. To date, 350 vent fields have been discovered, and there is enormous potential to revolutionise the world’s mining industry. However, this dream will never be achievable unless we first develop resilient new mining technologies.
You have been commissioned by the Underwater Prospecting R&D branch of a UK mining company to design part of a minerals harvesting system. Your company has secured an initial contract to mine 1 million tonnes of copper-containing ore per year. The purchasing price of the material you mine will depend on the quality of the ore. It would therefore be advantageous to gather information on the copper content of rocks in order to target mining activity most cost-effectively. The specific task of your research group is to design a system that will locate mineral deposits on the ocean floor and take samples using a remotely operated drill.
Your design for a drill that intelligently searches for copper deposits should include an estimation of both building and running costs.
You will have to decide how you will analyse the samples. How accurate do you need to be and how small and simplified can the analysis equipment be made?
One reason for drilling for mineral samples is to reduce the possibility of only analysing ocean floor rock, rather than what lies beneath the seabed. How do you ensure that your system is collecting representative data? What kind of samples does your machine need to extract? How many samples, and of what size will be needed, and how should these be spread across the search field? What will the processing sequence be? Will it be necessary to store samples inside your device?
Gathering information about activity far below the ocean’s surface may be problematic, you may need to think about how to transmit information to guide your device and how to process any data received from underwater. You will have to decide how much remote control will be required, and what operations and decisions your system will be able to make independently.
Have you considered the materials that would be most appropriate to protect the device and make it failsafe in the extreme hydrothermal environment? How will the drill be moved around with precision, and monitor its position and local environment? What current technologies are suited for similar submarine environments?
Hydrothermal vent fields are bio-diverse areas and there are concerns that proposed mining activities may cause an environmental catastrophe. You should consider how to minimise the impact of your device on this relatively unexplored environment.