Minerals processing – extracting valuable metals and minerals from raw ore – has not changed substantially over the last 50 years. Some estimates say that the crushing box uses 30 – 40% of the total energy needed to extract the metal or mineral. For base metals alone, this equates to a staggering 2 – 4% of global energy use currently. So how can minerals processing make small changes that have a big difference?
The stakes are high, but small changes can have a significant impact towards a more sustainable processing value chain. Australian producers, manufacturers and researchers are determined to leave no stone unturned to accelerate and operationalise technologies that shift the dial. Associate Professor Liza Forbes, Group Leader Flotation Chemistry at The University of Queensland, says there are two changes the industry can focus on to break new ground in sustainability.
Innovative tailings management
The valuable components in ore often comprise a tiny percentage of the whole. The by-products, or tailings, represent a major environmental management issue. Recent industry events, like the catastrophic failure of the Brumadinho tailings dam in Brazil, have galvanised real change and kick-started valuable industry-wide collaboration. Amid many smaller global dam failures, Brumadinho was a huge wake-up call. In the aftermath, stringent regulations and financial consequences (to the tune of US$7 billion for owners Vale Mining) will lead to safer practices as a basic requirement of operation.
The University of Queensland’s Sustainable Minerals Institute is at the forefront of innovation in tailings management. Just a few examples include:
Evaluating the critical metal content of tailings deposits all around Australia and finding new ways to reprocess them to extract any valuable material.
Finding ways to extract secondary value material from mineral ores for industrial use in roads and buildings, or further refine it to recreate soil for revegetation, or sequester it safely.
Reducing the need to crush the ore into extremely fine particles, to reduce energy requirements.
Introducing step changes further up the value chain for successful tailings management, to produce useable materials, safer storage and accounting for long-term and far downstream impacts.
Associate Professor Forbes manages a diverse team of researchers. Alongside the technical expertise and pioneering discoveries, in every project she stresses the essential need for collaboration, as viewing any step in the minerals value chain in isolation means lost opportunities to optimise the entirety.
Speaking from long experience, she emphasises, “It just can’t be done without cross-disciplinary cooperation with specialists in every aspect. It’s also important to recognise the collaborations between different types of stakeholders, such as producers, manufacturers, local communities, Indigenous and government interests, as excluding any party from the overall project will damage progress.”
The 2020 Juukan Gorge incident, an example of another major event closer to home, will stand as a reminder of the fundamental imperative of building and maintaining vigorous, meaningful collaboration with every party involved throughout the mining lifecycle, taking local and Indigenous cultural considerations into all development conversations.
Associate Professor Forbes agrees that while there’s mostly personal willingness to collaborate, it is not easy – competing interests, different KPIs, and incompatibilities in performance incentives are areas that can be resolved. People cannot be removed from the equation, so putting aside personal clashes, we can and must learn to work together.
Discussions that lead to a safer industry
Associate Professor Forbes will be contributing to important industry conversations in the conference program at the free-to-attend Asia-Pacific’s International Mining Exhibition (AIMEX) in Sydney from 5 – 7 September. She will be part of two panel discussions at AIMEX: A Tuesday 5 September panel on what is needed to delivery net zero in the supply chain, and a Wednesday 6 September panel examining collaborative R&D for technical innovation in mining.
Improvements in technology and processes for minerals processing have existed for up to 20 years, but have only found wide acceptance recently, since change has become critical, and researchers have improved viability. As global demand builds, now is the time to turn blue-sky ideas into a safer, energy-conserving minerals processing industry, together.
Source: global mining review