How to transform your mining project and drive innovation to achieve successful results
This article explores industry drivers and challenges facing current projects.
Drawing on the authors’ experience, it provides insight into practical developments, including new and emerging approaches, that are creating step-changes in projects. As a result, we are helping producers meet market expectations and improve a wide range of environmental, social and governance (ESG) outcomes. Some examples of recent projects where innovation was key to achieving successful results are presented.
Market forces are reshaping projects and operations: decreasing orebody grades, more complex metallurgy, shifting commodity focus, increasing demand for resources, high commodity prices, national sovereignty focus and a virus that has impacted travel and resulted in increasing freight, equipment and bulk materials costs are examples. In addition to these headwinds, the investment markets are demanding improved ESG performance and a drive toward net zero emissions.
We continue to see global copper projects decrease in grade and reserves, while larger projects with simple metallurgy tend to have increasingly complex social and environmental issues that impact permitting.
Supergene and oxide gold projects are diminishing in frequency, scale and grade. Other gold projects in Australia and Africa are transitioning from non-refractory to refractory ore sources, requiring additional processing complexity through oxidation circuits to maintain acceptable recoveries. Spiking demand for battery metals is driving development of new projects and markets; meanwhile, circular economies are emerging to manage the battery revolution.
How to transform mining projects
Our aim is to maximise the value of projects through smart thinking.
Common pitfalls include a lack of focus on fundamental business economics, over-capitalisation, mismanaged constraints, conservatism, poor engineering, poor assumptions, or lack of good and timely decisions.
A good project team manages the business and project constraints and improves the outcomes for all stakeholders. Improvements can be achieved through new and different approaches that fundamentally improve recoveries, increase product purities, shrink capital and operating costs and better manage project impacts.
With strong business economics as the basis, engineering solutions that may (or may not yet) exist in the market can be adapted to address specific technical challenges. For some projects, a ‘back to basics’ rethink is all that is required. Other times, an innovative approach is necessary, which can involve researchers, technology start-ups, inhouse experts, commercialisation partners and forward-thinking clients in order to maintain a competitive edge. Successful methodologies and solutions from one project often translate to another.
Some recent case studies that briefly describe how teams of resources professionals transformed projects to deliver great outcomes are presented below.
Mina Justa oxide and sulfide copper projects
At Mina Justa, we worked with Marcobre to understand the fundamental project economics and to drive value. We simultaneously designed and built a 6 Mt/y sulphide plant and a 12 Mt/y oxide plant. This enabled revenue to be generated from the 100 m deep layer of near surface lower-margin oxide ore, while enabling access to deeper higher grade sulphide ore to generate returns earlier. This approach improved the economics of the project, which had been studied for decades.
Newcrest’s Cadia coarse particle flotation circuit
For Newcrest, at the Cadia mine site in Orange, NSW, our teams engineered a coarse particle flotation circuit that was commissioned in 2018. This was the first application of the Eriez Hydrofloat™ technology in a hard rock application.
This circuit has enabled Newcrest to coarsen grind sizes, increase copper and gold recoveries, increase throughputs, and reduce energy consumption, media consumption and operating costs per metal produced. We are studying and implementing this technology for a range of existing operations and new projects, and we expect this technology will continue to achieve step change reductions in energy, water and operating costs across the industry for both fine and coarse-grained ores.
Preconcentration at Ravenswood
Pre-concentration enables low-grade ore to be rejected earlier in the value chain, preserving energy and water. At Ravenswood Gold in North Queensland, we are completing an expansion that leverages a characteristic evidenced in some orebodies, where gold preferentially associates with finer (rather than coarser) particles in the crushing circuit. Rejecting coarser and lower grade ores at Ravenswood enables over 30 per cent reduction in energy and water compared to milling those same particles. The same approach can be applied to a range of other orebodies and commodities under the right conditions.
Related content: Site experience at Ausenco
Hear from Ausenco staff about the opportunities as a mining engineer to work both in an office and an operating site, including the above mentioned Ravenswood Gold.
Optimising power, tailings sand and price certainty
For Mantos Copper on the Mantoverde project, we optimised the tailings transport system to install a second thickener and reduce the energy that would otherwise have been wasted pumping water for no gain. The project also includes a tailings sand cyclone station that produces sand for tailings storage facility (TSF) wall construction (reducing the amount of fill required), while also increasing water recovery from the tailings facility. This tailings sand approach is common in South America but less so in Australia, in part due to finer mineralogies and finer grind sizes.
Optimisation projects leveraging data
We continue to provide consulting services to optimise operations, focusing on the use of data, particularly within the comminution circuit. Our success leverages small data, experience and expert knowledge of the cause and effects within systems to provide a quick return on investment to achieve specific objectives.
Once short-term gains are realised, the focus shifts to larger data sets with expanded focus on machine learning techniques, but still with defined objectives and outcomes. This methodology is continually driven by the fundamentals of the system by those with operations backgrounds who understand the practical context of the data. This approach mitigates against data 'analysis paralysis' and correlation versus causation errors which are common pitfalls for data-driven optimisation projects.
These brief case studies of step-change outcomes demonstrate how the expertise and knowledge of resources professionals can help continues to redefine the paradigms for schedule and cost performance, while also being able to adapt to fit the specific needs of the market and the project.
If you’d like to know more about any of the case studies contained in this article, please contact Matt Pyle.