Coupling of electrokinetics with in situ leach mining for next generation “key-hole” mining of metals from ores and wastes, [Mining and Minerals Engineering] – PhD (Funded)

The Problem:
Last year more than 99% of the mass of all metals were extracted from the Earth via physical excavation which comprises the complete removal of surface soil and overburden rock (and associated biological inhabitants), in order to gain access to the ore. The ore is then typically crushed to a fine powder before being processed (e.g. via smelting) to remove the gangue material (often >90% by volume) and thereby yield the final pure metal product. Overall the process results in staggeringly large quantities of solid waste (approximately 20 times larger than all global municipal waste generation) whilst also being responsible for 26% of all global CO2 emissions. It is therefore clear that current mining paradigm is fundamentally unsustainable.
The Solution:
This PhD project will seek to deliver a new technology for the mining and waste reprocessing industries which will enable the recovery of metals from ores and legacy waste with radically less environmental disturbance, mine waste generation and energy input. In particular the research will focus on developing a mechanistic understanding of how we can combine in situ leach mining with electrokinetics and other hybrid approaches (ultrasonication, microwave activity, etc.) in order to: (1) precisely control the subsurface movement of a leaching chemical; and (2) “force” it through low hydraulic conductivity geological formations.
The specific aims of project are to:
(1) Collect and characterise ore and mine waste from across the UK which span a range of different mineralogy potentially applicable for electrokinetic in situ leach mining.
(2) Determine how we can synthesise, and optimise the application of, next generation lixiviants which are selective for target metal dissolution from ores and mine waste.
(3) Determine what electrokinetic conditions are best suited to control both lixiviant leaching efficacy and transport through porous systems.
(4) Determine what hybrid techniques may be applicable to enhance the approach even further.

This exciting project will benefit from the world-class facilities at the Camborne School of Mines & the Environment and Sustainability Institute, University of Exeter and will also comprise fieldwork at several interesting legacy mine sites in the SW of England.

The studentship will be awarded on the basis of merit for 3.5 years of full-time study to commence in September 2020.