Low cost, In-mine solutions
Common modern mining techniques require ore to be blasted, transported and reduced to a fine particle state before extracting metals. These processes often require massive amounts of energy and leave behind a large footprint. The global mining industry is now calling for transformative and innovative processes that address future challenges of decreasing grades, deeper and more complex deposits and higher environmental standards.
Mining3’s ‘three pillar’ strategy aims to transform the mining industry through Lean Mining, In-Place Mining, and Sustainability through Technology.
In-Mine Recovery (IMR), under the In-Place Mining pillar, focuses on minimising rock disturbance, surface footprint and costs associated with the mine to mill process. Rather than the traditional digging and dumping method, IMR involves ore fragmentation and leaching from within the mine, removing the need for large amounts of rock movement.
The IMR method will have a technical cross-over with In-Situ Recovery (ISR). In ISR, lixiviants are injected and extracted using a series of wells drilled from the surface to leach target ores. Mining3 is already in partnerships through the M519 initiative and Kapundar Copper CRC-P to develop and test eco-friendly lixiviants for small target deposits. The ISR method differs from IMR in that it requires very specific environmental conditions including target deposits being below the water table, with good permeability contained within impermeable geological structures. IMR, in contrast, relies on the rock mass being conditioned for leaching, where the leach fluids interact with the ore and are controlled with underground silos and the pregnant solution is then recovered from within the mine itself.
Technical challenges of IMR are understanding the capabilities of emerging lixiviant technology, identifying novel mine design methods and their constraints, barrier technologies, and adapting intelligent ore fragmentation methods with minimal rock transport.
Surface heap leaching has been proven for leaching base and precious metal ores, and the science and practice of fracturing rock through blasting, cutting or caving is well understood. However, there are significant challenges in bringing these components together into a working system underground. Industry developments in eco-friendly lixiviants, distributed sensors, hard rock cutting, automation, and smart ‘digital’ blasting enables this vision to be realised.
The IMR method, although yielding less material, costs far less to maintain and therefore could sustain a much lower cut-off grade (break-even grade to determine feasibility of mining) sustaining or even increasing profitability. The design and process of IMR is malleable and can therefore be applied in either greenfield or brownfield mine sites.
The concept of underground in-mine recovery in this manner is not currently being pursued by public research institutions anywhere in Australia. Mining3 plans to investigate the method further by conducting research to overcome technical challenges and demonstrate the viability of the technique.
If you are interested in learning more about the IMR method or wish to partner with Mining3, please contact us here.